Gene Literature Dashboard

Viewing June 2008 — 137 paper(s) from the local store. (Local view only — run without --view to fetch new papers.)
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Also flagged:canceroncogenessignal transductioncervical carcinomaBCL2TP53
Journal Article 2008-06-30 ✓ 1 Snippet Chu LH, Chen BS.
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…CDC6, MFN2, PKMYT1,DCC, and E2F1 in…

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<h4>Background</h4>Cancer is caused by genetic abnormalities, such as mutations of oncogenes or tumor suppressor genes, which alter downstream signal transduction pathways and protein-protein interactions. Comparisons of the interactions of proteins in cancerous and normal cells can shed light on the mechanisms of carcinogenesis.<h4>Results</h4>We constructed initial networks of protein-protein interactions involved in the apoptosis of cancerous and normal cells by use of two human yeast two-hybrid data sets and four online databases. Next, we applied a nonlinear stochastic model, maximum likelihood parameter estimation, and Akaike Information Criteria (AIC) to eliminate false-positive protein-protein interactions in our initial protein interaction networks by use of microarray data. Comparisons of the networks of apoptosis in HeLa (human cervical carcinoma) cells and in normal primary lung fibroblasts provided insight into the mechanism of apoptosis and allowed identification of potential drug targets. The potential targets include BCL2, caspase-3 and TP53. Our comparison of cancerous and normal cells also allowed derivation of several party hubs and date hubs in the human protein-protein interaction networks involved in caspase activation.<h4>Conclusion</h4>Our method allows identification of cancer-perturbed protein-protein interactions involved in apoptosis and identification of potential molecular targets for development of anti-cancer drugs.

Also flagged:haemochromatosisHepcidinerythropoiesisiron
Journal Article 2008-06-28 ✓ 5 Snippets van Dijk BA, Laarakkers CM, Klaver SM, Jacobs EM, van Tits LJ, Janssen MC, Swinkels DW.
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Serum hepcidin levels are innately low in HFE-related haemochromatosis but differ between C282Y-homozygotes with elevated and normal ferritin levels.

This study showed that serum hepcidin is innately low in HFE-related haemochromatosis.

…innately low inHFE-related haemochromatosis but …

HFEC282Y-homozygosity has been…

…of newly diagnosedHFEC282Y-homozygotes with (N…

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HFE C282Y-homozygosity has been associated with low hepcidin expression, leading to increased ferritin levels. However, serum hepcidin protein levels have not been documented in humans. In the current study, we compared serum hepcidin levels of newly diagnosed HFE C282Y-homozygotes with (N = 15) and without (N = 7) elevated serum ferritin levels to levels of 40 controls (20 heterozygotes and 20 wild types). In addition, hepcidin levels of four C282Y homozygotes were investigated during the course of all phlebotomy treatment phases. Serum hepcidin levels were lower in HFE C282Y-homozygotes (median; 25th-75th percentile: 1.88; 0.78-2.77 nmol/l) compared to controls (2.74; 1.45-5.39). Hepcidin/ferritin ratios were also lower in homozygotes. Homozygotes with an elevated serum ferritin had a higher serum hepcidin but a lower hepcidin/ferritin ratio than those with normal ferritin (2.28; 1.62-3.23 nmol/l hepcidin vs. 0.80; 0.60-1.29 and 3.63; 2.72-7.59 pmol hepcidin/microg ferritin vs. 13.2; 5.15-14.2). Serum hepcidin decreased during the depletion phase of phlebotomy and remained low during maintenance. This study showed that serum hepcidin is innately low in HFE-related haemochromatosis. Elevated ferritin levels were associated with increased hepcidin levels while erythropoiesis lead to lower hepcidin levels. During depletion, therefore, hepcidin levels are decreased, which may exacerbate intestinal iron absorption.

Also flagged:cancerorganogenesishomeoboxprostatehomeobox geneembryogenesis
Journal Article 2008-06-28 ✓ 1 Snippet Abate-Shen C, Shen MM, Gelmann E.
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Prdx6

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Several tissue-specific regulatory genes have been found to play essential roles in both organogenesis and carcinogenesis. In the prostate, the Nkx3.1 homeobox gene plays an important role in normal differentiation of the prostatic epithelium while its loss of function is an initiating event in prostate carcinogenesis in both mouse models and human patients. Thus, the Nkx3.1 homeobox gene provides a paradigm for understanding the relationship between normal differentiation and cancer, as well as studying the roles of homeobox genes in these processes. Here, we review recent findings concerning the roles of Nkx3.1 in development and discuss how its normal function is disrupted in processes of early prostate carcinogenesis.

Also flagged:porphyria cutanea tardaIroninfectionpathogenesisTFR2HCV infection
Journal Article 2008-06-28 ✓ 5 Snippets Kratka K, Dostalikova-Cimburova M, Michalikova H, Stransky J, Vranova J, Horak J.
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To determine the prevalence of the HFE gene mutations p.Cys282Tyr (C282Y), p.His63Asp (H63D) and p.Ser65Cys (S65C), the p.Tyr250X (Y250X) mutation of the TFR2 gene, and HCV infection in patients with PCT in the Czech population, and to make comparison of the iron status among the respective genotypes.

High prevalence of HFE gene mutations in patients with porphyria cutanea tarda in the Czech Republic.

<h4>Background</h4>Iron overload and hepatitis C virus (HCV) infection are independent factors which are thought to play a role in the pathogenesis of porphyria cutanea tarda (PCT).<h4>Objectives</h4>To determine the prevalence of the HFE gene mutations p.Cys282Tyr (C282Y), p.His63Asp (H63D) and p.Ser65Cys (S65C), the p.Tyr250X (Y250X) mutation of the TFR2 gene, and HCV infection in patients with PCT in the Czech population, and to make comparison of the iron status among the respective genotypes.<h4>Methods</h4>Iron metabolism indices, results of mutational analysis and serological markers of HCV infection were examined in 63 patients with PCT.<h4>Results</h4>The HFE gene mutations were detected in 70% of patients with PCT compared with 35% in the control group (P < 0.001).

…High prevalence ofHFEgene mutations in…

…prevalence of theHFEgene mutations p.Cys282Tyr…

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<h4>Background</h4>Iron overload and hepatitis C virus (HCV) infection are independent factors which are thought to play a role in the pathogenesis of porphyria cutanea tarda (PCT).<h4>Objectives</h4>To determine the prevalence of the HFE gene mutations p.Cys282Tyr (C282Y), p.His63Asp (H63D) and p.Ser65Cys (S65C), the p.Tyr250X (Y250X) mutation of the TFR2 gene, and HCV infection in patients with PCT in the Czech population, and to make comparison of the iron status among the respective genotypes.<h4>Methods</h4>Iron metabolism indices, results of mutational analysis and serological markers of HCV infection were examined in 63 patients with PCT.<h4>Results</h4>The HFE gene mutations were detected in 70% of patients with PCT compared with 35% in the control group (P < 0.001). Mean serum ferritin levels were increased in all genotypes, the highest being in homozygotes for the p.Cys282Tyr mutation. HCV infection was detected in only 8% of patients with PCT.<h4>Conclusions</h4>There was a very high prevalence of the p.Cys282Tyr and p.His63Asp mutations observed in patients with PCT accompanied by mild degrees of iron overload, which was genotype dependent.

Also flagged:immune deficiencyencephalitismicrobial infectiondeathHIV-1 infectionneurocognitive disorder
Journal Article 2008-06-28 No Snippets Wang T, Gong N, Liu J, Kadiu I, Kraft-Terry SD, Schlautman JD, Ciborowski P, Volsky DJ, Gendelman HE.
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The human immunodeficiency virus (HIV) invades the central nervous system early after viral exposure but causes progressive cognitive, behavior, and motor impairments years later with the onset of immune deficiency. Although in the brain, HIV preferentially replicates productively in cells of mononuclear phagocyte (MP; blood borne macrophage and microglia), astrocytes also can be infected, at low and variable frequency, particularly in patients with encephalitis. Among their many functions, astrocytes network with microglia to provide the first line of defense against microbial infection; however, very little is known about astrocytes' consequences on MP. Here, we addressed this question using co-culture systems of HIV-infected mouse astrocytes and microglia. Pseudotyped vesicular stomatis virus/HIV was used to circumvent the absence of viral receptors and ensure cell genotypic uniformity for studies of intercellular communication. The study demonstrated that infected astrocytes show modest changes in protein elements compared to uninfected cells. In contrast, infected astrocytes induce robust changes in the proteome of HIV-1-infected microglia. Accelerated cell death and redox proteins, among others, were produced in abundance. The observations confirmed the potential of astrocytes to influence the neuropathogenesis of HIV-1 infection by specifically altering the neurotoxic potential of infected microglia and regulating viral maturation.

Also flagged:biosynthesistaxanebaccatin IIItransferasecarbodiimideformic acid
Journal Article 2008-06-28 No Snippets Long RM, Lagisetti C, Coates RM, Croteau RB.
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The last few steps in the biosynthesis of the anticancer drug Taxol in yew (Taxus) species are thought to involve the attachment of beta-phenylalanine to the C13-O-position of the advanced taxane diterpenoid intermediate baccatin III to yield N-debenzoyl-2'-deoxytaxol, followed by hydroxylation on the side chain at the C2'-position to afford N-debenzoyltaxol, and finally N-benzoylation to complete the pathway. A cDNA encoding the N-benzoyl transferase that catalyzes the terminal step of the reaction sequence was previously isolated from a family of transferase clones (derived from an induced Taxus cell cDNA library) by functional characterization of the corresponding recombinant enzyme using the available surrogate substrate N-debenzoyl-2'-deoxytaxol [K. Walker, R. Long, R. Croteau, Proc. Nat. Acad. Sci. USA 99 (2002) 9166-9171]. Semi-synthetic N-debenzoyltaxol was prepared by coupling of 7-triethylsilybaccatin III and (2R,3S)-beta-phenylisoserine protected as the N-Boc N,O-isopropylidene derivative by means of carbodiimide activation and formic acid deprotections. The selectivity of the recombinant N-transferase for N-debenzoyltaxol was evaluated, and the enzyme was shown to prefer, by a catalytic efficiency factor of two, N-debenzoyltaxol over N-debenzoyl-2'-deoxytaxol as the taxoid co-substrate in the benzoyl transfer reaction, consistent with the assembly sequence involving 2'-hydroxylation prior to N-benzoylation. Selectivity for the acyl/aroyl-CoA co-substrate was also examined, and the enzyme was shown to prefer benzoyl-CoA. Transfer from tigloyl-CoA to N-debenzoyltaxol to afford cephalomannine (Taxol B) was not observed, nor was transfer observed from hexanoyl-CoA or butanoyl-CoA to yield Taxol C or Taxol D, respectively. These results support the proposed sequence of reactions for C13-O-side chain assembly in Taxol biosynthesis, and suggest that other N-transferases are responsible for the formation of related, late pathway, N-acylated taxoids.

Also flagged:amino acidfloxuridineamino acid monoesteroligopeptide transportersPEPT1membrane
Journal Article 2008-06-28 No Snippets Tsume Y, Vig BS, Sun J, Landowski CP, Hilfinger JM, Ramachandran C, Amidon GL.
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A series of amino acid monoester prodrugs of floxuridine was synthesized and evaluated for the improvement of oral bioavailability and the feasibility of target drug delivery via oligopeptide transporters. All floxuridine 5'-amino acid monoester prodrugs exhibited PEPT1 affinity, with inhibition coefficients of Gly-Sar uptake (IC50) ranging from 0.7 - 2.3 mM in Caco-2 and 2.0 - 4.8 mM in AsPC-1 cells, while that of floxuridine was 7.3 mM and 6.3 mM, respectively. Caco-2 membrane permeabilities of floxuridine prodrugs (1.01 - 5.31 x 10(-6 )cm/sec) and floxuridine (0.48 x 10(-6 )cm/sec) were much higher than that of 5-FU (0.038 x 10(-6) cm/sec). MDCK cells stably transfected with the human oligopeptide transporter PEPT1 (MDCK/hPEPT1) exhibited enhanced cell growth inhibition in the presence of the prodrugs. This prodrug strategy offers great potential, not only for increased drug absorption but also for improved tumor selectivity and drug efficacy.

Also flagged:methylationdemethylationNanogLefty1Tdgf1nucleosome
Journal Article 2008-06-27 No Snippets Farthing CR, Ficz G, Ng RK, Chan CF, Andrews S, Dean W, Hemberger M, Reik W.
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DNA methylation patterns are reprogrammed in primordial germ cells and in preimplantation embryos by demethylation and subsequent de novo methylation. It has been suggested that epigenetic reprogramming may be necessary for the embryonic genome to return to a pluripotent state. We have carried out a genome-wide promoter analysis of DNA methylation in mouse embryonic stem (ES) cells, embryonic germ (EG) cells, sperm, trophoblast stem (TS) cells, and primary embryonic fibroblasts (pMEFs). Global clustering analysis shows that methylation patterns of ES cells, EG cells, and sperm are surprisingly similar, suggesting that while the sperm is a highly specialized cell type, its promoter epigenome is already largely reprogrammed and resembles a pluripotent state. Comparisons between pluripotent tissues and pMEFs reveal that a number of pluripotency related genes, including Nanog, Lefty1 and Tdgf1, as well as the nucleosome remodeller Smarcd1, are hypomethylated in stem cells and hypermethylated in differentiated cells. Differences in promoter methylation are associated with significant differences in transcription levels in more than 60% of genes analysed. Our comparative approach to promoter methylation thus identifies gene candidates for the regulation of pluripotency and epigenetic reprogramming. While the sperm genome is, overall, similarly methylated to that of ES and EG cells, there are some key exceptions, including Nanog and Lefty1, that are highly methylated in sperm. Nanog promoter methylation is erased by active and passive demethylation after fertilisation before expression commences in the morula. In ES cells the normally active Nanog promoter is silenced when targeted by de novo methylation. Our study suggests that reprogramming of promoter methylation is one of the key determinants of the epigenetic regulation of pluripotency genes. Epigenetic reprogramming in the germline prior to fertilisation and the reprogramming of key pluripotency genes in the early embryo is thus crucial for transmission of pluripotency.

Also flagged:ironoverloadarthritisdiabetesliver diseaseheart disease
Journal Article 2008-06-27 ✓ 5 Snippets Acton RT, Barton JC, Passmore LV, Adams PC, McLaren GD, Leiendecker-Foster C, Speechley MR, Harris EL, Castro O, Reiss JA, Snively BM, Harrison BW, McLaren CE.
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There was 100% concordance of HFE genotype C282Y/C282Y in 6 probands and 8 of their siblings who reported having hemochromatosis or iron overload.

HFE genotype C282Y/C282Y in probands and siblings who reported having hemochromatosis

HFE genotype C282Y/C282Y in 6 probands and 8 of their siblings who reported having hemochromatosis

…family history ofhemochromatosisor iron overload:…

…iron overload: thehemochromatosisand iron overload…

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<h4>Background & aims</h4>The aim of this study was to assess the analytic validity of self-reported family history of hemochromatosis or iron overload.<h4>Methods</h4>A total of 141 probands, 549 family members, and 641 controls participated in the primary care Hemochromatosis and Iron Overload Screening Study. Participants received a postscreening clinical examination and completed questionnaires about personal and family histories of hemochromatosis or iron overload, arthritis, diabetes, liver disease, and heart disease. We evaluated sensitivities and specificities of proband-reported family history, and concordance of HFE genotype C282Y/C282Y in probands and siblings who reported having hemochromatosis or iron overload.<h4>Results</h4>The sensitivities of proband-reported family history ranged from 81.4% for hemochromatosis or iron overload to 18.4% for liver disease; specificities for diabetes, liver disease, and heart disease were greater than 94%. Hemochromatosis or iron overload was associated with a positive family history across all racial/ethnic groups in the study (odds ratio, 14.53; 95% confidence intervals, 7.41-28.49; P < .0001) and among Caucasians (odds ratio, 16.98; 95% confidence intervals, 7.53-38.32; P < .0001). There was 100% concordance of HFE genotype C282Y/C282Y in 6 probands and 8 of their siblings who reported having hemochromatosis or iron overload.<h4>Conclusions</h4>Self-reported family history of hemochromatosis or iron overload can be used to identify individuals whose risk of hemochromatosis or iron overload and associated conditions is increased. These individuals could benefit from further evaluation with iron phenotyping and HFE mutation analysis.

Also flagged:androgen receptorHuntington diseaseARspinobulbar muscular atrophyprostate cancerdegradation
Journal Article 2008-06-27 ✓ 5 Snippets Chandra S, Shao J, Li JX, Li M, Longo FM, Diamond MI.
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Huntington disease derives from a critically expanded polyglutamine tract in the huntingtin (Htt) protein; a similar polyglutamine expansion in the androgen receptor (AR) causes spinobulbar muscular atrophy.

Transfer of the Htt motif with five flanking amino acids on either side to YFP reduces the steady state YFP level by rendering it susceptible to proteasome degradation.

…in the huntingtin (Htt) protein; a similar…

…mechanisms that regulateHttand AR degradation…

…(FQKLL) within theHttprotein regulates its…

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Huntington disease derives from a critically expanded polyglutamine tract in the huntingtin (Htt) protein; a similar polyglutamine expansion in the androgen receptor (AR) causes spinobulbar muscular atrophy. AR activity also plays an essential role in prostate cancer. Molecular mechanisms that regulate Htt and AR degradation are not well understood but could have important therapeutic implications. We find that a pentapeptide motif (FQKLL) within the Htt protein regulates its degradation and subcellular localization to cytoplasm puncta. Disruption of the motif by alanine substitution at the hydrophobic residues increases the steady state level of the protein. Pulsechase analyses indicate that the motif regulates degradation. A similar motif (FQNLF) has corresponding activities in the AR protein. Transfer of the Htt motif with five flanking amino acids on either side to YFP reduces the steady state YFP level by rendering it susceptible to proteasome degradation. This work defines a novel proteasome-targeting motif that is necessary and sufficient to regulate the degradation of two disease-associated proteins.

Also flagged:OPNphosphoproteincollagenfibrilssaltcalcium
Journal Article 2008-06-27 No Snippets Zappone B, Thurner PJ, Adams J, Fantner GE, Hansma PK.
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Using an atomic force microscope and a surface force apparatus, we measured the surface coverage, adhesion, and mechanical properties of layers of osteopontin (OPN), a phosphoprotein of the human bones, adsorbed on mica. OPN is believed to connect mineralized collagen fibrils of the bone in a matrix that dissipates energy, reducing the risk of fractures. Atomic force microscopy normal force measurements showed large adhesion and energy dissipation upon retraction of the tip, which were due to the breaking of the many OPN-OPN and OPN-mica bonds formed during tip-sample contact. The dissipated energy increased in the presence of Ca(2+) ions due to the formation of additional OPN-OPN and OPN-mica salt bridges between negative charges. The forces measured by surface force apparatus between two macroscopic mica surfaces were mainly repulsive and became hysteretic only in the presence of Ca(2+): adsorbed layers underwent an irreversible compaction during compression due to the formation of long-lived calcium salt bridges. This provides an energy storage mechanism, which is complementary to energy dissipation and may be equally relevant to bone recovery after yield. The prevalence of one mechanism or the other appears to depend on the confinement geometry, adsorption protocol, and loading-unloading rates.

Also flagged:Right ventricular (RV) dysfunctioncongenital heart diseaseRV hypertrophypulmonary stenosisPSclusterin
Journal Article 2008-06-27 No Snippets Urashima T, Zhao M, Wagner R, Fajardo G, Farahani S, Quertermous T, Bernstein D.
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Right ventricular (RV) dysfunction is a common long-term complication in patients after the repair of congenital heart disease. Previous investigators have examined the cellular and molecular mechanisms of left ventricular (LV) remodeling, but little is known about the stressed RV. Our purpose was to provide a detailed physiological characterization of a model of RV hypertrophy and failure, including RV-LV interaction, and to compare gene alterations between afterloaded RV versus LV. Pulmonary artery constriction was performed in 86 mice. Mice with mild and moderate pulmonary stenosis (PS) developed stable hypertrophy without decompensation. Mice with severe PS developed edema, decreased RV function, and high mortality. Tissue Doppler imaging demonstrated septal dyssynchrony and deleterious RV-LV interaction in the severe PS group. Microarray analysis showed 196 genes with increased expression and 1,114 with decreased expression. Several transcripts were differentially increased in the afterloaded RV but not in the afterloaded LV, including clusterin, neuroblastoma suppression of tumorigenicity 1, Dkk3, Sfrp2, formin binding protein, annexin A7, and lysyl oxidase. We have characterized a murine model of RV hypertrophy and failure, providing a platform for studying the physiological and molecular events of RV remodeling. Although the molecular responses of the RV and LV to afterload stress are mostly concordant, there are several key differences, which may represent targets for RV failure-specific therapy.

Also flagged:malemetal-responsive transcription factor 1detoxificationsmall regulatory proteinchromatinhistone
Journal Article 2008-06-27 ✓ 1 Snippet Vardanyan A, Atanesyan L, Egli D, Raja SJ, Steinmann-Zwicky M, Renkawitz-Pohl R, Georgiev O, Schaffner W.
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…dosage compensation complex (DCC), which among other…

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<h4>Background</h4>Metal-responsive transcription factor 1 (MTF-1), which binds to metal response elements (MREs), plays a central role in transition metal detoxification and homeostasis. A Drosophila interactome analysis revealed two candidate dMTF-1 interactors, both of which are related to the small regulatory protein Dumpy-30 (Dpy-30) of the worm C. elegans. Dpy-30 is the founding member of a protein family involved in chromatin modifications, notably histone methylation. Mutants affect mating type in yeast and male mating in C. elegans.<h4>Results</h4>Constitutive expression of the stronger interactor, Dpy-30L1 (CG6444), in transgenic flies inhibits MTF-1 activity and results in elevated sensitivity to Cd(II) and Zn(II), an effect that could be rescued by co-overexpression of dMTF-1. Electrophoretic mobility shift assays (EMSA) suggest that Dpy-30L1 interferes with the binding of MTF-1 to its cognate MRE binding site. Dpy-30L1 is expressed in the larval brain, gonads, imaginal discs, salivary glands and in the brain, testes, ovaries and salivary glands of adult flies. Expression of the second interactor, Dpy-30L2 (CG11591), is restricted to larval male gonads, and to the testes of adult males. Consistent with these findings, dpy-30-like transcripts are also prominently expressed in mouse testes. Targeted gene disruption by homologous recombination revealed that dpy-30L1 knockout flies are viable and show no overt disruption of metal homeostasis. In contrast, the knockout of the male-specific dpy-30L2 gene results in male sterility, as does the double knockout of dpy-30L1 and dpy-30L2. A closer inspection showed that Dpy-30L2 is expressed in elongated spermatids but not in early or mature sperm. Mutant sperm had impaired motility and failed to accumulate in sperm storage organs of females.<h4>Conclusion</h4>Our studies help to elucidate the physiological roles of the Dumpy-30 proteins, which are conserved from yeast to humans and typically act in concert with other nuclear proteins to modify chromatin structure and gene expression. The results from these studies reveal an inhibitory effect of Dpy-30L1 on MTF-1 and an essential role for Dpy-30L2 in male fertility.

Also flagged:PPARGC1Anonalcoholic fatty liver diseaseNAFLDNASHperoxisome proliferators-activated receptor γ coactivator 1αsimple steatosis
Journal Article 2008-06-27 ✓ 1 Snippet Yoneda M, Hotta K, Nozaki Y, Endo H, Uchiyama T, Mawatari H, Iida H, Kato S, Hosono K, Fujita K, Yoneda K, Takahashi H, Kirikoshi H, Kobayashi N, Inamori M, Abe Y, Kubota K, Saito S, Maeyama S, Wada K, Nakajima A.
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…(PBC), sclerosing cholangitis,hemochromatosis, α1-antitrypsin deficiency, W…

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<h4>Background</h4>Genetic factors as well as environmental factors are important in the development of NAFLD and in this study we investigated associations between polymorphisms of peroxisome proliferators-activated receptor gamma coactivator 1alpha polymorphism (PPARGC1A) and NAFLD.<h4>Aims</h4>We recruited 115 patients with biopsy-proven NAFLD, 65 with NASH and 50 with simple steatosis, and 441 healthy control subjects and investigated 15 SNPs of PPARGC1A.<h4>Results</h4>SNP rs2290602 had the lowest p value in the dominant mode (p = 0.00095), and the odds ratio for NAFLD (95% CI) was 2.73 (1.48 - 5.06). rs2290602 was significantly associated with NAFLD even when the most conservative Bonferroni's correction was applied (p = 0.0143). The frequency of the T allele of rs2290602 was significantly higher in the NASH patients than in the control subjects (p = 0.00093, allele frequency mode), and its frequency in the NASH patients tended to be higher than in the simple steatosis patients (p = 0.09). The results of the real-time RT-PCR study showed that intrahepatic mRNA expression of PPARGC1A was lower in the TT group than in the GG or GT group at SNP rs2290602 (p = 0.0454).<h4>Conclusion</h4>This is the first study to demonstrate a significant association between genetic variations in PPARGC1A and NAFLD. This finding suggested that PPARGC1A polymorphism and lower expression of PPARGC1A mRNA in the liver are an important genetic contribution to etiology of NAFLD.

Also flagged:ubiquitinPRC1PcG repressive complex 1PRC2histone 3 lysine 27 methyltransferasegene silencing
Journal Article 2008-06-27 ✓ 1 Snippet Sanchez-Pulido L, Devos D, Sung ZR, Calonje M.
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…characterized are thePcG repressive complexrepressive complex (PRC)1…

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<h4>Background</h4>Polycomb group (PcG) proteins are a set of chromatin-modifying proteins that play a key role in epigenetic gene regulation. The PcG proteins form large multiprotein complexes with different activities. The two best-characterized PcG complexes are the PcG repressive complex 1 (PRC1) and 2 (PRC2) that respectively possess histone 2A lysine 119 E3 ubiquitin ligase and histone 3 lysine 27 methyltransferase activities. While PRC2-like complexes are conserved throughout the eukaryotic kingdoms, PRC1-like complexes have only been described in Drosophila and vertebrates. Since both complexes are required for the gene silencing mechanism in Drosophila and vertebrates, how PRC1 function is realized in organisms that apparently lack PRC1 such as plants, is so far unknown. In vertebrates, PRC1 includes three proteins, Ring1B, Ring1A, and Bmi-1 that form an E3 ubiquitin ligase complex. These PRC1 proteins have an N-terminally located Ring finger domain associated to a poorly characterized conserved C-terminal region.<h4>Results</h4>We obtained statistically significant evidences of sequence similarity between the C-terminal region of the PRC1 Ring finger proteins and the ubiquitin (Ubq)-like family proteins, thus defining a new Ubq-like domain, the RAWUL domain. In addition, our analysis revealed the existence of plant and worm proteins that display the conserved combination of a Ring finger domain at the N-terminus and a RAWUL domain at the C-terminus.<h4>Conclusion</h4>Analysis of the conserved domain architecture among PRC1 Ring finger proteins revealed the existence of long sought PRC1 protein orthologs in these organisms, suggesting the functional conservation of PRC1 throughout higher eukaryotes.

Also flagged:metabotropic glutamate receptor 1mGlu1deathglutamatemGlu1 receptorsdependence
Journal Article 2008-06-27 ✓ 1 Snippet Pshenichkin S, Dolińska M, Klauzińska M, Luchenko V, Grajkowska E, Wroblewski JT.
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DCC

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Group I metabotropic glutamate receptors have been often implicated in various models of neuronal toxicity, however, the role played by the individual receptors and their putative mechanisms of action contributing to neurotoxicity or neuroprotection remain unclear. Here, using primary cultures of rat cerebellar granule cells and mouse cortical neurons, we show that conditions of trophic deprivation increased mGlu1 expression which correlated with the developing cell death. The inhibition of mGlu1 expression by specific siRNA attenuated toxicity, while adenovirus-mediated overexpression of mGlu1 resulted in increased cell death, indicating a causal relationship between the level of receptor expression and neuronal survival. In pharmacological experiments selective mGlu1 antagonists failed to protect from mGlu1-induced cell death, instead, neuronal survival was promoted by glutamate acting at mGlu1 receptors. Such properties are characteristics of a novel heterogeneous family of dependence receptors which control neuronal apoptosis. Our findings indicate that increased expression of mGlu1 in neurons creates a state of cellular dependence on the presence of its endogenous agonist glutamate. We propose a new role and a new mechanism for mGlu1 action. This receptor may play a crucial role in determining the fate of individual neurons during the development of the nervous system.

Also flagged:cystinecysteineglutathionedisulfideagingage-related diseases
Journal Article 2008-06-27 No Snippets Johnson JM, Strobel FH, Reed M, Pohl J, Jones DP.
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<h4>Background</h4>The steady-state redox potential of the cysteine/cystine couple in human plasma provides a measure of oxidative stress, yet available assays are limited by either specificity or speed of assay.<h4>Method</h4>The present study evaluated the use of LC-FTMS for identification based on accurate mass combined with quantification by stable isotopic dilution to rapidly determine cysteine and cystine concentration and cysteine/cystine steady-state redox potential in human plasma.<h4>Results</h4>A simple extraction procedure followed by a rapid LC separation eluted cysteine in 4 min and cystine in 1.5 min with simultaneous measurement of glutathione (GSH) and glutathione disulfide (GSSG). A study of five young (mean age=25.7) subjects and 5 older (mean age=67.8 y) subjects showed an increased oxidation with age.<h4>Conclusions</h4>The analysis by LC-FTMS is suitable for high-throughput analysis of plasma cysteine, cystine and cysteine/cystine steady-state redox potential as clinical measures of oxidative stress.

Also flagged:transcription factorschromatinepilepsydrug addictiondepressionneurodegenerative diseases
Journal Article 2008-06-26 ✓ 1 Snippet Barrett RM, Wood MA.
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chromatin modifiers

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One of the alluring aspects of examining chromatin modifications in the role of modulating transcription required for long-term memory processes is that these modifications may provide transient and potentially stable epigenetic marks in the service of activating and/or maintaining transcriptional processes. These, in turn, may ultimately participate in the molecular mechanisms required for neuronal changes subserving long-lasting changes in behavior. As an epigenetic mechanism of transcriptional control, chromatin modification has been shown to participate in maintaining cellular memory (e.g., cell fate) and may underlie the strengthening and maintenance of synaptic connections required for long-term changes in behavior. Epigenetics has become central to several fields of neurobiology, where researchers have found that regulation of chromatin modification has a significant role in epilepsy, drug addiction, depression, neurodegenerative diseases, and memory. In this review, we will discuss the role of chromatin modifying enzymes in memory processes, as well as how recent studies in yeast genetics and cancer biology may impact the way we think about how chromatin modification and chromatin remodeling regulate neuronal function.

Also flagged:ironoverloadsinsulin-resistance iron overload syndromeHepcidininsulin resistancehepatic
Journal Article 2008-06-26 ✓ 3 Snippets Ruivard M.
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Type 1 haemochromatosis1 haemochromatosis C282Y…

…be elucidated: howHFEinterferes with hepcidin…

…with hepcidin intype 1 haemochromatosis1 haemochromatosis; the…

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Hepcidin inhibits intestinal absorption of iron through internalisation of ferroportin. Its discovery helps to better understand the genetic iron overloads. The insulin resistance-hepatic iron overload (IR-HIO)--also coined as the dysmetabolic iron overload syndrome--is a common cause or iron overload. This article is a review about genetic iron overloads and IR-HIO. Type 1 haemochromatosis C282Y +/+ accounts for 95% of the haemochromatosis. Hepatic fibrosis may develop if serum ferritin is higher than 1000 microg/l but can be partially reversible with phlebotomies. Juvenile haemochromatosis (type 2) and type 3 haemochromatosis (mutation of the transferrin receptor 2) are very uncommon. Several mutations of the ferroportin gene can cause usually mild iron overload of autosomal dominant inheritance. Aceruleoplasminemia is an uncommon disorder involving cerebral iron overload. The causes and consequences of the IR-HIO are unknown. Treatment of IR-HIO is focused on metabolic syndrome and phlebotomies are questionable because the overload is moderate and intestinal absorption of iron seems to be low. MRI (or other non invasive methods) is needed to truly assess iron overload because serum ferritin overestimates it in metabolic syndrome. Several points have to be elucidated: how HFE interferes with hepcidin in type 1 haemochromatosis; the causes of variability of iron overload; the benefits of populations screening; the advantage of phlebotomies in IR-HIO; the use of new oral iron chelators.

Also flagged:gene expressioninfectionVisceral leishmaniasisinfectious diseaseimmune responsesimmune response
Journal Article 2008-06-25 No Snippets Ettinger NA, Wilson ME.
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Visceral leishmaniasis is a potentially fatal infectious disease caused by the protozoan parasite Leishmania infantum/chagasi in the New World, or by L. donovani or L. infantum/chagasi in the Old World. Infection leads to a variety of outcomes ranging from asymptomatic infection to active disease, characterized by fevers, cachexia, hepatosplenomegaly and suppressed immune responses. We reasoned that events occurring during the initial few hours when the parasite encounters cells of the innate and adaptive immune systems are likely to influence the eventual immune response that develops. Therefore, we performed gene expression analysis using Affymetrix U133Plus2 microarray chips to investigate a model of early infection with human monocyte-derived macrophages (MDMs) challenged with wild-type L. chagasi parasites, with or without subsequent co-culture with Leishmania-naïve, autologous T-cells. Microarray data generated from total RNA were analyzed with software from the Bioconductor Project and functional clustering and pathway analysis were performed with DAVID and Gene Set Enrichment Analysis (GSEA), respectively. Many transcripts were down-regulated by infection in cultures containing macrophages alone, and the pattern indicated a lack of a classically activated phenotype. By contrast, the addition of autologous Leishmania-naïve T cells to infected macrophages resulted in a pattern of gene expression including many markers of type 1 immune cytokine activation (IFN-gamma, IL-6, IL-1alpha, IL-1beta). There was simultaneous up-regulation of a few markers of immune modulation (IL-10 cytokine accumulation; TGF-beta Signaling Pathway). We suggest that the initial encounter between L. chagasi and cells of the innate and adaptive immune system stimulates primarily type 1 immune cytokine responses, despite a lack of classical macrophage activation. This local microenvironment at the site of parasite inoculation may determine the initial course of immune T-cell development.

Also flagged:TFII-IGTF2IGTF2IRD1transcription factorWilliams syndromeneurodevelopmental disorder
Journal Article 2008-06-25 ✓ 1 Snippet Chimge NO, Makeyev AV, Ruddle FH, Bayarsaihan D.
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Cdk5rap1

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GTF2I and GTF2IRD1 encode members of the TFII-I transcription factor family and are prime candidates in the Williams syndrome, a complex neurodevelopmental disorder. Our previous expression microarray studies implicated TFII-I proteins in the regulation of a number of genes critical in various aspects of cell physiology. Here, we combined bioinformatics and microarray results to identify TFII-I downstream targets in the vertebrate genome. These results were validated by chromatin immunoprecipitation and siRNA analysis. The collected evidence revealed the complexity of TFII-I-mediated processes that involve distinct regulatory networks. Altogether, these results lead to a better understanding of specific molecular events, some of which may be responsible for the Williams syndrome phenotype.

Also flagged:Copperalbuminlactationnitrilotriacetatehistidinecopper transporter 1
Journal Article 2008-06-25 ✓ 1 Snippet Moriya M, Ho YH, Grana A, Nguyen L, Alvarez A, Jamil R, Ackland ML, Michalczyk A, Hamer P, Ramos D, Kim S, Mercer JF, Linder MC.
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hemochromatosis

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Ionic copper entering blood plasma binds tightly to albumin and the macroglobulin transcuprein. It then goes primarily to the liver and kidney except in lactation, where a large portion goes directly to the mammary gland. Little is known about how this copper is taken up from these plasma proteins. To examine this, the kinetics of uptake from purified human albumin and alpha(2)-macroglobulin, and the effects of inhibitors, were measured using human hepatic (HepG2) and mammary epithelial (PMC42) cell lines. At physiological concentrations (3-6 muM), both cell types took up copper from these proteins independently and at rates similar to each other and to those for Cu-dihistidine or Cu-nitrilotriacetate (NTA). Uptakes from alpha(2)-macroglobulin indicated a single saturable system in each cell type, but with different kinetics, and 65-80% inhibition by Ag(I) in HepG2 cells but not PMC42 cells. Uptake kinetics for Cu-albumin were more complex and also differed with cell type (as was the case for Cu-histidine and NTA), and there was little or no inhibition by Ag(I). High Fe(II) concentrations (100-500 microM) inhibited copper uptake from albumin by 20-30% in both cell types and that from alpha(2)-macroglobulin by 0-30%, and there was no inhibition of the latter by Mn(II) or Zn(II). We conclude that the proteins mainly responsible for the plasma-exchangeable copper pool deliver the metal to mammalian cells efficiently and by several different mechanisms. alpha(2)-Macroglobulin delivers it primarily to copper transporter 1 in hepatic cells but not mammary epithelial cells, and additional as-yet-unidentified copper transporters or systems for uptake from these proteins remain to be identified.

Also flagged:gene expressionADpathogenesisagingAD dementiadeath
Journal Article 2008-06-24 No Snippets Liang WS, Dunckley T, Beach TG, Grover A, Mastroeni D, Ramsey K, Caselli RJ, Kukull WA, McKeel D, Morris JC, Hulette CM, Schmechel D, Reiman EM, Rogers J, Stephan DA.
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While the clinical and neuropathological characterization of Alzheimer's Disease (AD) is well defined, our understanding of the progression of pathologic mechanisms in AD remains unclear. Post-mortem brains from individuals who did not fulfill clinical criteria for AD may still demonstrate measurable levels of AD pathologies to suggest that they may have presented with clinical symptoms had they lived longer or are able to stave off disease progression. Comparison between such individuals and those clinically diagnosed and pathologically confirmed to have AD will be key in delineating AD pathogenesis and neuroprotection. In this study, we expression profiled laser capture microdissected non-tangle bearing neurons in 6 post-mortem brain regions that are differentially affected in the AD brain from 10 non-demented individuals demonstrating intermediate AD neuropathologies (NDAD; Braak stage of II through IV and CERAD rating of moderate to frequent) and evaluated this data against that from individuals who have been diagnosed with late onset AD as well as healthy elderly controls. We identified common statistically significant expression changes in both NDAD and AD brains that may establish a degenerative link between the two cohorts, in addition to NDAD specific transcriptomic changes. These findings pinpoint novel targets for developing earlier diagnostics and preventative therapies for AD prior to diagnosis of probable AD. We also provide this high-quality, low post-mortem interval (PMI), cell-specific, and region-specific NDAD/AD reference data set to the community as a public resource.

Also flagged:schizophreniaserotonin transporterpsychosishaloperidolrisperidoneschizoaffective disorders
Journal Article 2008-06-24 ✓ 4 Snippets Dolzan V, Serretti A, Mandelli L, Koprivsek J, Kastelic M, Plesnicar BK.
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In the present study, we investigated the effects of the 44 bp insertion/deletion polymorphism in the promoter region of 5-HTT gene (5-HTTLPR) on symptomatology of psychosis and clinical response to antipsychotic drugs.

In the present study, we investigated the effects of the 44 bp insertion/deletion polymorphism in the promoter region of 5-HTT gene (5-HTTLPR) on symptomatology of psychosis and clinical response to antipsychotic drugs.<h4>Methods</h4>In total 56 patients acutely treated with haloperidol or risperidone either for the first episode of schizophrenia, schizophreniform or schizoaffective disorders, or for the relapse of these psychotic disorders after tapering their maintenance treatment, were genotyped for the 5-HTTLPR L and S alleles and for the new A/G functional variant within the L alelle (La/g).

…h4>The serotonin transporter (5-HTT) plays an important…

…promoter region of5-HTTgene (5-HTTLPR) on…

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<h4>Background</h4>The serotonin transporter (5-HTT) plays an important role in serotonergic neurotransmission. In the present study, we investigated the effects of the 44 bp insertion/deletion polymorphism in the promoter region of 5-HTT gene (5-HTTLPR) on symptomatology of psychosis and clinical response to antipsychotic drugs.<h4>Methods</h4>In total 56 patients acutely treated with haloperidol or risperidone either for the first episode of schizophrenia, schizophreniform or schizoaffective disorders, or for the relapse of these psychotic disorders after tapering their maintenance treatment, were genotyped for the 5-HTTLPR L and S alleles and for the new A/G functional variant within the L alelle (La/g). Psychopathological symptoms were assessed with the Brief Psychiatric Rating Scale (BPRS) and with Clinical Global Impression (CGI) twice: at 8-12 days after the first dose of antipsychotic and after 4 weeks. Extrapyramidal side effects were assessed with the Simpson-Angus Extrapyramidal Side Effects Scale (EPS), the Barnes Akathisia Scale (BARS) and the Abnormal Involuntary Movement Scale (AIMS).<h4>Results</h4>Age, body mass index (BMI), illness duration, drug type and dosage were considered as covariates when analysing association with genetic variants as they were associated with baseline or final BPRS and CGI scores and/or extrapyramidal side effects. 5-HTTLPR was not associated with baseline and final BPRS and CGI scores or with the CGI% reduction. However, the 5-HTTLPR S allele was associated with a lower improvement in BPRS scores (P=0.022) and this effect was even stronger after pooling subjects with S or Lg containing alleles (P=0.006). We did not observe any effect of 5-HTTLPR on acute antipsychotics side effects.<h4>Conclusion</h4>Present result supports a contribution of serotonin system to neuroleptics efficacy for the treatment of schizophrenia. The analysis of the La/g functional variant may significantly improve the predictive power of 5-HTTLPR genotyping and represent a step further towards the development of the personalized antipsychotic treatment.

Also flagged:GFPCD11cCD11bCD205TNF-αIFN-γ
Journal Article 2008-06-24 No Snippets Deepe GS, Gibbons RS, Smulian AG.
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Numerous in vitro studies have demonstrated that Histoplasma capsulatum is engulfed by the diverse populations of phagocytic cells including monocytes/macrophages (Mphi), immature dendritic cells (DC), and neutrophils. The in vivo distribution of H. capsulatum has yet to be examined following an intrapulmonary challenge. To accomplish this goal, we engineered GFP into two genetically dissimilar strains of H. capsulatum, G217B and 186R. C57BL/6 mice were infected with each of these strains, and we analyzed the distribution of this fungus in the three major phagocytic populations on successive days. Yeast cells were found in all three populations of cells from Days 1 through 7. Proportionally, DC dominated at Day 1, whereas the majority of yeast cells was detected in neutrophils thereafter. Yeast cells were present in inflammatory and resident Mphi on Day 3, but on Day 7, they were chiefly in inflammatory Mphi. Yeast cells were predominantly in a CD11c(+intermediate/high), F4/80(-), CD11b(+), Ly-6C(+), CD205(+) DC population. Neutralization of TNF-alpha or IFN-gamma produced a significant redistribution of yeast cells. These results reveal the complex nature of intracellular residence of this fungus. Moreover, the findings demonstrate that there is a skewing in the subpopulations of cells that are infected, especially DC.

Also flagged:neurodegenerative diseasespeptidesprion encephalopathiesconformational diseasesserine proteasepeptide
Journal Article 2008-06-23 ✓ 4 Snippets Carrell RW, Mushunje A, Zhou A.
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…Human α-antithrombin (ATIII) and α1-antitrypsin (α1AT)…

…Polymers ofATIIIor α1AT were…

…reactive loop ofATIII) or VTFKA (strand…

…of C-sheet ofATIII) were prepared from…

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Many disorders, including Alzheimer's, the prion encephalopathies and other neurodegenerative diseases, result from aberrant protein aggregation. Surprisingly, cellular toxicity is often due not to the highly-ordered aggregates but to the oligomers that precede their formation. Using serpins as a paradigm, we show how the active and infective interface of oligomers is inherently toxic and can promiscuously bind to unrelated peptides, including neurotransmitters. Extension of the oligomer and its eventual sequestration as amyloid can thus be seen as a protective response to block the toxic interface. We illustrate how the preferential self-association that gives this protection has been selectively favoured.

Also flagged:SynthesismetabolismdipeptideacyclovirInfectioncorneal opacities
Journal Article 2008-06-23 No Snippets Talluri RS, Samanta SK, Gaudana R, Mitra AK.
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The objective of this study was to synthesize and evaluate novel enzymatically stable dipeptide prodrugs for improved absorption of acyclovir. l-Valine-l-valine-acyclovir (LLACV), l-valine-d-valine-acyclovir (LDACV), d-valine-l-valine-acyclovir (DLACV) and d-valine-d-valine-acyclovir (DDACV) were successfully synthesized. The uptake and transport studies were conducted on a Caco-2 cell line. Buffer stability and metabolism of the prodrugs in Caco-2, rat intestine and liver homogenates were studied. Structure and purity of the all compounds were confirmed with LC-MS/MS and NMR spectroscopy. Uptake and transport of [(3)H] glycylsarcosine was inhibited by all prodrugs except DDACV. DLACV and DDACV exhibited no measurable degradation in Caco-2 homogenate. Except DDACV other three prodrugs were hydrolyzed in rat intestine and liver homogenates. The order of permeability across Caco-2 was LDACV>LLACV>DDACV>DLACV. A linear correlation between the amount of prodrug transported and over all permeability of acyclovir was established. This study shows that the incorporation of one d-valine in a dipeptide did not abolish its affinity towards peptide transporters (PEPT). Moreover, it enhanced enzymatic stability of prodrug to a certain extent depending on the position in a dipeptide conjugate. This strategy improved both the cellular permeability and the amount of intact prodrug transported which would enable targeting the nutrient transporters at blood ocular barrier (BOB).

Also flagged:PhosphorylationROCK1Y-27632Rho-associated kinaseROCKHuntington disease
Journal Article 2008-06-23 ✓ 5 Snippets Shao J, Welch WJ, Diprospero NA, Diamond MI.
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…effects on huntingtin (Htt) aggregation and toxicity…

…also interacts withHtt, as being a…

…tion of polyglutamine-expandedHttand androgen receptor…

…direct interaction withHtt, which are both…

…both AR andHttaggregation.…

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Y-27632, an inhibitor of the Rho-associated kinase ROCK, is a therapeutic lead for Huntington disease (HD). The downstream targets that mediate its inhibitory effects on huntingtin (Htt) aggregation and toxicity are unknown. We have identified profilin, a small actin-binding factor that also interacts with Htt, as being a direct target of the ROCK1 isoform. The overexpression of profilin reduces the aggregation of polyglutamine-expanded Htt and androgen receptor (AR) peptides. This requires profilin's G-actin binding activity and its direct interaction with Htt, which are both inhibited by the ROCK1-mediated phosphorylation of profilin at Ser-137. Y-27632 blocks the phosphorylation of profilin in HEK293 cells and primary neurons, which maintains profilin in an active state. The knockdown of profilin blocks the inhibitory effect of Y-27632 on both AR and Htt aggregation. A signaling pathway from ROCK1 to profilin thus controls polyglutamine protein aggregation and is targeted by a promising therapeutic lead for HD.

In praise of arrays.

Also flagged:gene-expressiontranslationalChronic allograft nephropathyimmune responsetubular atrophyinterstitial fibrosis
Journal Article 2008-06-21 No Snippets Ying L, Sarwal M.
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Microarray technologies have both fascinated and frustrated the transplant community since their introduction roughly a decade ago. Fascination arose from the possibility offered by the technology to gain a profound insight into the cellular response to immunogenic injury and the potential that this genomic signature would be indicative of the biological mechanism by which that stress was induced. Frustrations have arisen primarily from technical factors such as data variance, the requirement for the application of advanced statistical and mathematical analyses, and difficulties associated with actually recognizing signature gene-expression patterns and discerning mechanisms. To aid the understanding of this powerful tool, its versatility, and how it is dramatically changing the molecular approach to biomedical and clinical research, this teaching review describes the technology and its applications, as well as the limitations and evolution of microarrays, in the field of organ transplantation. Finally, it calls upon the attention of the transplant community to integrate into multidisciplinary teams, to take advantage of this technology and its expanding applications in unraveling the complex injury circuits that currently limit transplant survival.

Also flagged:SemaphorinPlexinNeuropilinnucleussecretionaxons
Journal Article 2008-06-21 ✓ 1 Snippet Xu C, Fan CM.
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DCC

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The hypothalamic paraventricular nucleus (PVN) and supraoptic nucleus (SON) contain neuroendocrine cells that modulate pituitary secretion to maintain homeostasis. These two nuclei have a common developmental origin but they eventually form at locations distant from each other. Little is known about the molecular cues that direct the segregation of PVN and SON. As a means to identify potential factors, we have documented expression patterns of genes with known guidance roles in neural migration. Here, we focus on two groups of ligand/receptor families classified to mediate chemo-repulsion of neurons and their axons: the Slit/Robo and the Semaphorin/Plexin/Neuropilin families. Their dynamic expression patterns within and around the common PVN/SON progenitor as well as the mature PVN and SON may provide a framework for understanding the formation of these two important nuclei.

Also flagged:agingMitochondriacytoplasmicorganellescalciumdeath
Journal Article 2008-06-20 ✓ 1 Snippet Reddy PH.
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Htt

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Mitochondria are key cytoplasmic organelles, responsible for generating cellular energy, regulating intracellular calcium levels, altering the reduction-oxidation potential of cells, and regulating cell death. Increasing evidence suggests that mitochondria play a central role in aging and in neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and Freidriech ataxia. Further, several lines of evidence suggest that mitochondrial dysfunction is an early event in most late-onset neurodegenerative diseases. Biochemical and animal model studies of inherited neurodegenerative diseases have revealed that mutant proteins of these diseases are associated with mitochondria. Mutant proteins are reported to block the transport of nuclear-encoded mitochondrial proteins to mitochondria, interact with mitochondrial proteins and disrupt the electron transport chain, induce free radicals, cause mitochondrial dysfunction, and, ultimately, damage neurons. This article discusses critical issues of mitochondria causing dysfunction in aging and neurodegenerative diseases, and discusses the potential of developing mitochondrial medicine, particularly mitochondrially targeted antioxidants, to treat aging and neurodegenerative diseases.

Also flagged:cell cyclenicotinamide adenine dinucleotidenicotinamide mononucleotide adenylyltransferase 1pituitary tumor transforming gene 1ubiquitinproteasome
Journal Article 2008-06-20 No Snippets Wishart TM, Pemberton HN, James SR, McCabe CJ, Gillingwater TH.
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<h4>Background</h4>Altered neuronal vulnerability underlies many diseases of the human nervous system, resulting in degeneration and loss of neurons. The neuroprotective slow Wallerian degeneration (Wlds) mutation delays degeneration in axonal and synaptic compartments of neurons following a wide range of traumatic and disease-inducing stimuli, providing a powerful experimental tool with which to investigate modulation of neuronal vulnerability. Although the mechanisms through which Wlds confers neuroprotection remain unclear, a diverse range of downstream modifications, incorporating several genes/pathways, have been implicated. These include the following: elevated nicotinamide adenine dinucleotide (NAD) levels associated with nicotinamide mononucleotide adenylyltransferase 1 (Nmnat1; a part of the chimeric Wlds gene); altered mRNA expression levels of genes such as pituitary tumor transforming gene 1 (Pttg1); changes in the location/activity of the ubiquitin-proteasome machinery via binding to valosin-containing protein (VCP/p97); and modified synaptic expression of proteins such as ubiquitin-activating enzyme E1 (Ube1).<h4>Results</h4>Wlds expression in mouse cerebellum and HEK293 cells induced robust increases in a broad spectrum of cell cycle-related genes. Both NAD-dependent and Pttg1-dependent pathways were responsible for mediating different subsets of these alterations, also incorporating changes in VCP/p97 localization and Ube1 expression. Cell proliferation rates were not modified by Wlds, suggesting that later mitotic phases of the cell cycle remained unaltered. We also demonstrate that Wlds concurrently altered endogenous cell stress pathways.<h4>Conclusion</h4>We report a novel cellular phenotype in cells with altered neuronal vulnerability. We show that previous reports of diverse changes occurring downstream from Wlds expression converge upon modifications in cell cycle status. These data suggest a strong correlation between modified cell cycle pathways and altered vulnerability of axonal and synaptic compartments in postmitotic, terminally differentiated neurons.

Also flagged:estrogenestrogensmethylnicotinic acidesteramine
Journal Article 2008-06-20 No Snippets Yang WC, Regnier FE, Sliva D, Adamec J.
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A fast and sensitive LC-ESI-MS method is described for the comparative quantification of 16 estrogen metabolites based on the derivatization of estrogens with a novel derivatizing reagent, N-methyl-nicotinic acid N-hydroxysuccinimide ester (C1-NA-NHS). The process introduces a quaternary amine to the analytes, making the analytes permanently charged regardless of the pH of the high-performance liquid chromatography (HPLC) mobile phase. This quaternization resulted in a highly efficient separation of 16 estrogen metabolites in 7 min at a detection level below 1 ng/mL. By using a deuterated derivatizing reagent (C1-d(3)-NA-NHS), a complete set of deuterated standards was utilized and used as internal standards in a comparative quantification and recovery study, demonstrating acceptable results over a wide concentration range. A pooled breast cancer serum sample was analyzed using the described method, and 15 estrogens were detected in the range of 80-530 pg/mL.

Also flagged:alpha-1-antitrypsindeficiencyAlpha-1-antitrypsin deficiencyAATDgenetic disorder
Journal Article 2008-06-19 ✓ 2 Snippets Fregonese L, Stolk J.
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…jaundice, viral infection,hemochromatosis, Wilson's disease and…

…include viral infection,hemochromatosis, Wilson's disease and…

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Alpha-1-antitrypsin deficiency (AATD) is a genetic disorder that manifests as pulmonary emphysema, liver cirrhosis and, rarely, as the skin disease panniculitis, and is characterized by low serum levels of AAT, the main protease inhibitor (PI) in human serum. The prevalence in Western Europe and in the USA is estimated at approximately 1 in 2,500 and 1 : 5,000 newborns, and is highly dependent on the Scandinavian descent within the population. The most common deficiency alleles in North Europe are PI Z and PI S, and the majority of individuals with severe AATD are PI type ZZ. The clinical manifestations may widely vary between patients, ranging from asymptomatic in some to fatal liver or lung disease in others. Type ZZ and SZ AATD are risk factors for the development of respiratory symptoms (dyspnoea, coughing), early onset emphysema, and airflow obstruction early in adult life. Environmental factors such as cigarette smoking, and dust exposure are additional risk factors and have been linked to an accelerated progression of this condition. Type ZZ AATD may also lead to the development of acute or chronic liver disease in childhood or adulthood: prolonged jaundice after birth with conjugated hyperbilirubinemia and abnormal liver enzymes are characteristic clinical signs. Cirrhotic liver failure may occur around age 50. In very rare cases, necrotizing panniculitis and secondary vasculitis may occur. AATD is caused by mutations in the SERPINA1 gene encoding AAT, and is inherited as an autosomal recessive trait. The diagnosis can be established by detection of low serum levels of AAT and isoelectric focusing. Differential diagnoses should exclude bleeding disorders or jaundice, viral infection, hemochromatosis, Wilson's disease and autoimmune hepatitis. For treatment of lung disease, intravenous alpha-1-antitrypsin augmentation therapy, annual flu vaccination and a pneumococcal vaccine every 5 years are recommended. Relief of breathlessness may be obtained with long-acting bronchodilators and inhaled corticosteroids. The end-stage liver and lung disease can be treated by organ transplantation. In AATD patients with cirrhosis, prognosis is generally grave.

Also flagged:docdefectsSlackcell deathionsbeta-amyloid
Journal Article 2008-06-19 No Snippets Leung MC, Williams PL, Benedetto A, Au C, Helmcke KJ, Aschner M, Meyer JN.
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The nematode Caenorhabditis elegans has emerged as an important animal model in various fields including neurobiology, developmental biology, and genetics. Characteristics of this animal model that have contributed to its success include its genetic manipulability, invariant and fully described developmental program, well-characterized genome, ease of maintenance, short and prolific life cycle, and small body size. These same features have led to an increasing use of C. elegans in toxicology, both for mechanistic studies and high-throughput screening approaches. We describe some of the research that has been carried out in the areas of neurotoxicology, genetic toxicology, and environmental toxicology, as well as high-throughput experiments with C. elegans including genome-wide screening for molecular targets of toxicity and rapid toxicity assessment for new chemicals. We argue for an increased role for C. elegans in complementing other model systems in toxicological research.

Also flagged:COPDlung diseasegene expressionTXNpathogenesisChronic Obstructive Pulmonary Disease
Journal Article 2008-06-19 ✓ 1 Snippet Bentley AR, Emrani P, Cassano PA.
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PRDX6

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<h4>Background</h4>Observational epidemiological studies of dietary antioxidant intake, serum antioxidant concentration and lung outcomes suggest that lower levels of antioxidant defences are associated with decreased lung function. Another approach to understanding the role of oxidant/antioxidant imbalance in the risk of chronic obstructive pulmonary disease (COPD) is to investigate the role of genetic variation in antioxidant enzymes, and indeed family based studies suggest a heritable component to lung disease. Many studies of the genes encoding antioxidant enzymes have considered COPD or COPD related outcomes, and a systematic review is needed to summarise the evidence to date, and to provide insights for further research.<h4>Methods</h4>Genetic association studies of antioxidant enzymes and COPD/COPD related traits, and comparative gene expression studies with disease or smoking as the exposure were systematically identified and reviewed. Antioxidant enzymes considered included enzymes involved in glutathione metabolism, in the thioredoxin system, superoxide dismutases (SOD) and catalase.<h4>Results</h4>A total of 29 genetic association and 15 comparative gene expression studies met the inclusion criteria. The strongest and most consistent effects were in the genes GCL, GSTM1, GSTP1 and SOD3. This review also highlights the lack of studies for genes of interest, particularly GSR, GGT and those related to TXN. There were limited opportunities to evaluate the contribution of a gene to disease risk through synthesis of results from different study designs, as the majority of studies considered either association of sequence variants with disease or effect of disease on gene expression.<h4>Conclusion</h4>Network driven approaches that consider potential interaction between and among genes, smoke exposure and antioxidant intake are needed to fully characterise the role of oxidant/antioxidant balance in pathogenesis.

Also flagged:irontype 2 diabetesDiabetesmyocardial infarctioncerebrovascular diseaseretinopathy
Journal Article 2008-06-19 ✓ 5 Snippets Davis TM, Beilby J, Davis WA, Olynyk JK, Jeffrey GP, Rossi E, Boyder C, Bruce DG.
In-Text Gene Mentions

Directed screening for iron overload and/or HFE mutations appears unwarranted in patients with type 2 diabetes.

Prevalence, characteristics, and prognostic significance of HFE gene mutations in type 2 diabetes: the Fremantle Diabetes Study.

We have, therefore, analyzed data from the observational Fremantle Diabetes Study (FDS) to assess the effects of iron status and HFE mutations on the characteristics and outcome of type 2 diabetes.

Interestingly, the HEIRS study did not show that the main HFE mutations were associated with diabetes (21).

There were the expected associations between HFE gene status and serum iron and transferrin saturation but no differences in either diabetes treatment or in %B or %S between groups defined by the HFE mutations relevant to iron overload and no significant relationship between %B and %S and any index of iron status.

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<h4>Objective</h4>To examine the relationship between iron status, hereditary hemochromatosis (HFE) gene mutations, and clinical features and outcomes of type 2 diabetes in a well-characterized representative sample of community-based patients.<h4>Research design and methods</h4>HFE genotype data were available for 1,245 type 2 diabetic patients from the longitudinal observational Fremantle Diabetes Study (FDS), representing 96.2% of the total FDS type 2 diabetes cohort. Data were collected at recruitment between 1993 and 1996 and annually until the end of June 2001. Hospitalization and mortality data were available until the end of June 2006. The presence of the C282Y HFE mutation was determined in all subjects and H63D in C282Y heterozygotes. Fasting serum iron, transferrin, and ferritin were measured in all C282Y homozygotes and C282Y/H63D heterozygotes and in 286 randomly selected wild-type subjects. Multiple logistic regression analysis was performed to determine independent baseline associates of prevalent complications (myocardial infarction, cerebrovascular disease, retinopathy, neuropathy, and nephropathy), as was Cox proportional hazards modeling to determine predictors of incident complications and mortality.<h4>Results</h4>Although there were expected positive associations between HFE gene mutations and serum iron and transferrin saturation, there were no independent positive associations between HFE gene status and either microvascular or macrovascular complications in cross-sectional and longitudinal analyses. HFE gene status did not independently predict cardiac or all-cause mortality. Measures of iron metabolism including serum ferritin were not associated with combined microvascular or macrovascular end points.<h4>Conclusions</h4>Directed screening for iron overload and/or HFE mutations appears unwarranted in patients with type 2 diabetes.

Also flagged:reverse transcriptasehTERTpeptideprohibitinp53telomerase reverse transcriptase
Journal Article 2008-06-19 ✓ 1 Snippet Huang GP, Pan ZJ, Huang JP, Yang JF, Guo CJ, Wang YG, Zheng Q, Chen R, Xu YL, Wang GZ, Xi YM, Shen D, Jin J, Wang JF.
In-Text Gene Mentions

PRDX6

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<h4>Objectives</h4>Previous studies have reported immortalization and tumorigenicity of human mesenchymal stem cells (hMSCs) transduced with exogenous human telomerase reverse transcriptase (hTERT). We also have established a line of hMSCs transduced with hTERT (hTERT-hMSCs) and we have cultured these cells for 290 population doublings (PDs) during which they demonstrated a large proliferation potential but with no tumorigenicity. The aim of this study was to investigate the protein expression profile of hTERT-hMSCs with two-dimensional gel electrophoresis and peptide mass fingerprinting by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, to be able to analyse the effects of exogenous hTERT on protein expression in hMSCs.<h4>Materials and methods</h4>We generated proteome maps of primary hMSCs and hTERT-hMSCs at PD 95 and PD 275.<h4>Results</h4>A total of 1543 +/- 145 protein spots in gels of primary MSCs at PD 12, 1611 +/- 186 protein spots in gels of hTERT-hMSCs at PD 95 and 1451 +/- 126 protein spots in gels of hTERT-hMSCs at 275 PD were detected. One hundred of these were successfully identified, including 20 which were differentially expressed.<h4>Conclusions</h4>The results suggest that sustaining levels of prohibitin and p53 expression along with differential expression of proteins in hTERT-hMSCs provide an insight into lack of transforming activity of hTERT-hMSCs during cell proliferation.

Also flagged:Ironatherosclerosiscardiovascular diseasearterial diseaseangiotensin IIdeferoxamine
Journal Article 2008-06-19 ✓ 1 Snippet Sullivan JL.
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…macrophages in genetichemochromatosismay explain why…

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It has been proposed that iron depletion protects against cardiovascular disease. There is increasing evidence that one mechanism for this protection may involve a reduction in iron levels within atherosclerotic plaque. Large increases in iron concentration are seen in human atherosclerotic lesions in comparison to levels in healthy arterial tissue. In animal models, depletion of lesion iron levels in vivo by phlebotomy, systemic iron chelation treatment or dietary iron restriction reduces lesion size and/or increases plaque stability. A number of factors associated with increased arterial disease or increased cardiovascular events is also associated with increased plaque iron. In rats, infusion of angiotensin II increases ferritin levels and arterial thickness which are reversed by treatment with the iron chelator deferoxamine. In humans, a polymorphism for haptoglobin associated with increased cardiovascular disease is also characterized by increased lesional iron. Heme oxygenase 1 (HO1) is an important component of the system for mobilization of iron from macrophages. Human HO1 promoter polymorphisms causing weaker upregulation of the enzyme are associated with increased cardiovascular disease and increased serum ferritin. Increased cardiovascular disease associated with inflammation may be in part caused by elevated hepcidin levels that promote retention of iron within plaque macrophages. Defective retention of iron within arterial macrophages in genetic hemochromatosis may explain why there is little evidence of increased atherosclerosis in this disorder despite systemic iron overload. The reviewed findings support the concept that arterial plaque iron is a modifiable risk factor for atherogenesis.

Also flagged:autosomal dominant neurodegenerative disorderneurogenesispolyglutamineHDmotor disordercognitive decline
Journal Article 2008-06-19 ✓ 1 Snippet Lorincz MT, Zawistowski VA.
In-Text Gene Mentions

htt

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Huntington's disease is an uncommon autosomal dominant neurodegenerative disorder caused by expanded polyglutamine repeats. Increased neurogenesis was demonstrated recently in Huntington's disease post-mortem samples. In this manuscript, neuronally differentiated embryonic stem cells with expanded CAG repeats in the murine Huntington's disease homologue and neural progenitors isolated from the subventricular zone of an accurate mouse Huntington's disease were examined for increased neurogenesis. Embryonic stem cells with expanded CAG repeats in the murine Huntington's disease homologue were demonstrated to undergo facilitated differentiation first into neural progenitors, then into more mature neurons. Neural progenitor cells isolated from the subventricular zone of a Huntington's disease knock-in animal displayed increased production of neural progenitors and increased neurogenesis. These findings suggested that neuronally differentiating embryonic stem cells with expanded CAG repeats is a reasonable system to identify factors responsible for increased neurogenesis in Huntington's disease. Expression profiling analysis comparing neuronally differentiating embryonic stem cells with expanded CAG repeats to neuronally differentiating embryonic stem cells without expanded CAG repeats identified transcripts involved in development and transcriptional regulation as factors possibly mediating increased neurogenesis in response to expanded CAG repeats.

Also flagged:gene expressiondegradationpathogenesiscancersovarian cancercancer
Journal Article 2008-06-18 No Snippets Dahiya N, Sherman-Baust CA, Wang TL, Davidson B, Shih IeM, Zhang Y, Wood W, Becker KG, Morin PJ.
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<h4>Background</h4>MicroRNAs (miRNAs) represent a class of small non-coding RNAs that control gene expression by targeting mRNAs and triggering either translation repression or RNA degradation. Emerging evidence suggests the potential involvement of altered regulation of miRNA in the pathogenesis of cancers, and these genes are thought to function as both tumor suppressors and oncogenes.<h4>Methodology/principal findings</h4>Using microRNA microarrays, we identify several miRNAs aberrantly expressed in human ovarian cancer tissues and cell lines. miR-221 stands out as a highly elevated miRNA in ovarian cancer, while miR-21 and several members of the let-7 family are found downregulated. Public databases were used to reveal potential targets for the highly differentially expressed miRNAs. In order to experimentally identify transcripts whose stability may be affected by the differentially expressed miRNAs, we transfected precursor miRNAs into human cancer cell lines and used oligonucleotide microarrays to examine changes in the mRNA levels. Interestingly, there was little overlap between the predicted and the experimental targets or pathways, or between experimental targets/pathways obtained using different cell lines, highlighting the complexity of miRNA target selection.<h4>Conclusion/significance</h4>Our results identify several differentially expressed miRNAs in ovarian cancer and identify potential target transcripts that may be regulated by these miRNAs. These miRNAs and their targets may have important roles in the initiation and development of ovarian cancer.

Also flagged:Osteosarcomatumorschromosomal regionstumorsuppressor genesp53
Journal Article 2008-06-18 No Snippets Tang N, Song WX, Luo J, Haydon RC, He TC.
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Osteosarcoma is the most common nonhematologic malignancy of bone in children and adults. The peak incidence occurs in the second decade of life, with a smaller peak after age 50. Osteosarcoma typically arises around the growth plate of long bones. Most osteosarcoma tumors are of high grade and tend to develop pulmonary metastases. Despite clinical improvements, patients with metastatic or recurrent diseases have a poor prognosis. Here, we reviewed the current understanding of human osteosarcoma, with an emphasis on potential links between defective osteogenic differentiation and bone tumorigenesis. Existing data indicate osteosarcoma tumors display a broad range of genetic and molecular alterations, including the gains, losses, or arrangements of chromosomal regions, inactivation of tumor suppressor genes, and the deregulation of major signaling pathways. However, except for p53 and/or RB mutations, most alterations are not constantly detected in the majority of osteosarcoma tumors. With a rapid expansion of our knowledge about stem cell biology, emerging evidence suggests osteosarcoma should be regarded as a differentiation disease caused by genetic and epigenetic changes that interrupt osteoblast differentiation from mesenchymal stem cells. Understanding the molecular pathogenesis of human osteosarcoma could ultimately lead to the development of diagnostic and prognostic markers, as well as targeted therapeutics for osteosarcoma patients.

Also flagged:pneumococcal diseaseInfectious diseasesrespiratory tract infectionsotitis mediasinusitispneumonia
Journal Article 2008-06-17 ✓ 2 Snippets Karlsson D, Jansson A, Normark BH, Nilsson P.
In-Text Gene Mentions

DCC

…By combining decreasedDCCgroup size with…

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<h4>Background</h4>Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide, but also a common colonizer of the upper respiratory tract. The emergence and spread of antibiotic resistant pneumococcal strains has threatened effective therapy. The long-term effects of measures aiming to limit pneumococcal spread are poorly understood. Computational modeling makes it possible to conduct virtual experiments that are impractical to perform in real life and thereby allows a more full understanding of pneumococcal epidemiology and control efforts.<h4>Methods</h4>We have developed a contact network model to evaluate the efficacy of interventions aiming to control pneumococcal transmission. Demographic data from Sweden during the mid-2000s were employed. Analyses of the model's parameters were conducted to elucidate key determinants of pneumococcal spread. Also, scenario simulations were performed to assess candidate control measures.<h4>Results</h4>The model made good predictions of previous findings where a correlation has been found between age and pneumococcal carriage. Of the parameters tested, group size in day-care centers was shown to be one of the most important factors for pneumococcal transmission. Consistent results were generated from the scenario simulations.<h4>Conclusion</h4>We recommend, based on the model predictions, that strategies to control pneumococcal disease and organism transmission should include reducing the group size in day-care centers.

Also flagged:MHC class Imetabolismwound healingantigen presentationglycoproteinsMill1
Journal Article 2008-06-17 ✓ 2 Snippets Rabinovich BA, Ketchem RR, Wolfson M, Goldstein L, Skelly M, Cosman D.
In-Text Gene Mentions

…ary haemochromatosis protein (HFE), a molecule involved…

…LikeHFE, the Mill family…

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MHC class I family members serve multiple functions beyond antigen presentation. We provide insight into the structure, expression and function of the Mill subfamily. This family includes two surface glycoproteins, Mill1 and Mill2. Protein sequences for Mill1 and Mill2 are most highly related to the NKG2D ligands, MICA and MICB, but neither of them bound to NKG2D. Computer-based protein modelling indicated that hereditary haemochromatosis protein (HFE), a molecule involved in iron uptake, was most similar. Mill1 and Mill2 were observed on cycling thymocytes, proliferating smooth muscle cells and fibroblasts. Using soluble Mill proteins, we found evidence for a soluble ligand in serum. Like HFE, the Mill family may be involved in nutrient metabolism. Skin was one of the only three organs found to express transcripts for both Mill1 and Mill2. Addition of antibodies specific for Mill2 to wounded skin enhanced healing. Our results suggest a role for the Mill proteins in cellular metabolism, with possible therapeutic significance.

Also flagged:serotoninnicotinenicotine dependenceTPH1tryptophan hydroxylaseserotonin transporter
Journal Article 2008-06-17 ✓ 1 Snippet David SP, Johnstone EC, Murphy MF, Aveyard P, Guo B, Lerman C, Munafò MR.
In-Text Gene Mentions

5-HTT

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The serotonin pathway has been implicated in nicotine dependence and may influence smoking cessation. Therefore, 792 cigarette smokers from the Patch in Practice trial were genotyped for the tryptophan hydroxylase (TPH1 A779C), serotonin transporter (SLC6A45-HTTLPR), and 5-HT1A (HTR1A C-1019G) polymorphisms. Cox regression analysis did not demonstrate significant effects of any of the three genotypes on relapse to smoking: TPH1 (Reference AA; AC: hazard ratio (HR) 0.99, 95% confidence interval (CI) 0.78, 1.24, p=0.90; CC: HR 0.93, 95% CI 0.73, 1.18, p=0.55); 5-HTTLPR (Reference LL; SL: HR 1.01, 95% CI 0.85, 1.20, p=0.90; SS: HR 1.13, 95% CI 0.91, 1.39, p=0.27); HTR1A (Reference CC; CG: HR 1.04, 95% CI 0.86, 1.25, p=0.70; GG: HR 1.01, 95% CI 0.82, 1.24, p=0.93). Moreover, pooled analyses of data from all three extant pharmacogenetic NRT trials (N=1398) found no significant effect of 5-HTTLPR genotype on continuous abstinence at 12-week (Reference LL; SL: odds ratio (OR)=1.25, 95% CI 0.89, 1.74, p=0.19; SS: OR=1.31, 95% CI 0.86, 1.98, p=0.21) or 26-week follow-up (Reference LL; SL: OR=0.93, 95% CI 0.64, 1.33, p=0.68; SS: OR=1.00, 95% CI 0.63, 1.58, p=1.00). These data do not support a statistically or clinically significant moderating effect of these specific 5-HT pathway genetic variants on smoking cessation. However, the possibility remains that other variants in these or other 5-HT genes may influence NRT efficacy for smoking cessation in treatment seeking smokers.

Also flagged:olfactomedinprimary open-angle glaucomagene expressioncell adhesionSix1transcription factor
Journal Article 2008-06-17 No Snippets Paper W, Kroeber M, Heersink S, Stephan DA, Fuchshofer R, Russell P, Tamm ER.
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Myocilin is a 55-57kDa secreted glycoprotein and member of the olfactomedin family, which is mutated in some forms of primary open-angle glaucoma. To assess the effects of elevated amounts of myocilin on aqueous humor outflow dynamics in an in vivo system, transgenic betaB1-crystallin-MYOC mice have been developed that strongly overexpress myocilin in their eyes. The transgenic overexpression of myocilin results in an almost five-fold increase of secreted normal myocilin in the aqueous humor of betaB1-crystallin-MYOC mice. In the present study, we wanted to use betaB1-crystallin-MYOC as a tool to identify the response of ocular tissues to the presence of higher than normal amounts of myocilin, and to identify changes in gene expression that could help to shed light on the functional in vivo properties of myocilin. RNA was isolated from ocular tissues of betaB1-crystallin-MYOC mice and wild-type littermates. Changes in gene expression were determined by hybridization of gene microarrays and confirmed by real time RT-PCR and Western blotting. The expression of genes that had been found to be differentially regulated in betaB1-crystallin-MYOC mice was further analyzed in cultured human trabecular meshwork (HTM) cells treated with recombinant myocilin. Although betaB1-crystallin-MYOC mice do not have an obvious phenotype, a statistically significant up- and downregulation of several distinct genes was found when compared to gene expression in wild-type littermates. Among the genes that were found to be differentially regulated were Wasl, Ceacam1, and Spon2, which are involved in cell adhesion and cell-matrix interactions. Differences in expression were also found for Six1 which encodes for a transcription factor, and for Pftk1 whose gene product is a cdc2-related protein kinase. The expression of these genes was also found to be regulated in vitro in HTM cells treated with recombinant myocilin. Substantially higher amounts in ocular tissues of betaB1-crystallin-MYOC mice were found for connexin 46 and alphaB-crystallin. In addition, several genes that encode for olfactomedin proteins showed distinct changes in expression. Olfml3 was significantly downregulated, while Lphn1, Lphn2, and Lphn3 were significantly upregulated. Our findings support a role for myocilin in modulating cellular adhesion, and suggest functional processes that involve other proteins of the olfactomedin family.

Also flagged:pathogenesisHuntington's diseaseHDglutaminenucleussynaptosomes
Journal Article 2008-06-16 ✓ 5 Snippets Wang CE, Tydlacka S, Orr AL, Yang SH, Graham RK, Hayden MR, Li S, Chan AW, Li XJ.
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Accumulation of N-terminal mutant huntingtin in mouse and monkey models implicated as a pathogenic mechanism in Huntington's disease.

…transgenic monkeys expressing exon-1 htt with a 147-glutamine repeat ( 147Q…

HD mouse models demonstrating more severe phenotypes show earlier accumulation of N-terminal mutant htt fragments, which leads to the formation of htt aggregates that are primarily present in neuronal nuclei and processes, as well as glial cells.

Our findings suggest that the neuropathological phenotypes of HD stem largely from the accumulation of N-terminal mutant htt fragments and that this accumulation is determined by htt context and cell-type-dependent clearance of mutant htt.

A number of mouse models expressing mutant huntingtin (htt) with an expanded polyglutamine (polyQ) domain are useful for studying the pathogenesis of Huntington's disease (HD) and identifying appropriate therapies.

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A number of mouse models expressing mutant huntingtin (htt) with an expanded polyglutamine (polyQ) domain are useful for studying the pathogenesis of Huntington's disease (HD) and identifying appropriate therapies. However, these models exhibit neurological phenotypes that differ in their severity and nature. Understanding how transgenic htt leads to variable neuropathology in animal models would shed light on the pathogenesis of HD and help us to choose HD models for investigation. By comparing the expression of mutant htt at the transcriptional and protein levels in transgenic mice expressing N-terminal or full-length mutant htt, we found that the accumulation and aggregation of mutant htt in the brain is determined by htt context. HD mouse models demonstrating more severe phenotypes show earlier accumulation of N-terminal mutant htt fragments, which leads to the formation of htt aggregates that are primarily present in neuronal nuclei and processes, as well as glial cells. Similarly, transgenic monkeys expressing exon-1 htt with a 147-glutamine repeat (147Q) died early and showed abundant neuropil aggregates in swelling neuronal processes. Fractionation of HD150Q knock-in mice brains revealed an age-dependent accumulation of N-terminal mutant htt fragments in the nucleus and synaptosomes, and this accumulation was most pronounced in the striatum due to decreased proteasomal activity. Our findings suggest that the neuropathological phenotypes of HD stem largely from the accumulation of N-terminal mutant htt fragments and that this accumulation is determined by htt context and cell-type-dependent clearance of mutant htt.

Also flagged:Sox9high-mobility-group box transcription factorL-Sox5chondrogenesisAgc1proteoglycan
Journal Article 2008-06-16 ✓ 5 Snippets Han Y, Lefebvre V.
In-Text Gene Mentions

…L-Sox5 andSox6drive expression of…

…redundant L-Sox5 andSox6proteins to effect…

…their specific sites, L-Sox5/Sox6increases the efficiency…

…L-Sox5/Sox6similarly secures Sox9…

…-acting element and L-Sox5/Sox6binding to three…

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The Sry-related high-mobility-group box transcription factor Sox9 recruits the redundant L-Sox5 and Sox6 proteins to effect chondrogenesis, but the mode of action of the trio remains unclear. We identify here a highly conserved 359-bp sequence 10 kb upstream of the Agc1 gene for aggrecan, a most essential cartilage proteoglycan and key marker of chondrocyte differentiation. This sequence directs expression of a minimal promoter in both embryonic and adult cartilage in transgenic mice, in a manner that matches Agc1 expression. The chondrogenic trio is required and sufficient to mediate the activity of this enhancer. It acts directly, Sox9 binding to a critical cis-acting element and L-Sox5/Sox6 binding to three additional elements, which are cooperatively needed. Upon binding to their specific sites, L-Sox5/Sox6 increases the efficiency of Sox9 binding to its own recognition site and thereby robustly potentiates the ability of Sox9 to activate the enhancer. L-Sox5/Sox6 similarly secures Sox9 binding to Col2a1 (encoding collagen-2) and other cartilage-specific enhancers. This study thus uncovers critical cis-acting elements and transcription factors driving Agc1 expression in cartilage and increases understanding of the mode of action of the chondrogenic Sox trio.

Also flagged:5-hydroxytryptamine transporterfenfluramine5-HT transportereating disordersbehavioural-
Journal Article 2008-06-16 ✓ 5 Snippets Pringle A, Jennings KA, Line S, Bannerman DM, Higgs S, Sharp T.
In-Text Gene Mentions

Expression of the 5-HTT varies in the human population, and this variation may determine both individual differences in feeding and abnormal feeding behaviours such as eating disorders.<h4>Objectives</h4>The effects of 5-HTT expression on feeding and satiety were examined in a transgenic mouse model of 5-HTT overexpression.<h4>Materials and methods</h4>We measured free-feeding food intake and observed the behavioural satiety sequence (BSS) after food deprivation in mice at baseline and after administration of the anorectic drug fenfluramine.<h4>Results</h4>5-HTT overexpressing mice were both lighter and shorter than their wildtype littermates.

In transgenic mice, this disruption was evident at the 3 mg/kg dose, while in wildtypes, it emerged only at the 10-mg/kg dose.<h4>Conclusion</h4>These data suggest that overexpression of the 5-HTT does not lead to alterations in feeding or satiety in food-deprived mice but does increase the occurrence of other non-feeding behaviours in response to the 5-HT releasing agent fenfluramine.

…ale</h4>The 5-HT transporter (5-HTT) is implicated in…

…Expression of the5-HTTvaries in the…

…>Objectives</h4>The effects of5-HTTexpression on feeding…

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<h4>Rationale</h4>The 5-HT transporter (5-HTT) is implicated in the regulation of appetite. Expression of the 5-HTT varies in the human population, and this variation may determine both individual differences in feeding and abnormal feeding behaviours such as eating disorders.<h4>Objectives</h4>The effects of 5-HTT expression on feeding and satiety were examined in a transgenic mouse model of 5-HTT overexpression.<h4>Materials and methods</h4>We measured free-feeding food intake and observed the behavioural satiety sequence (BSS) after food deprivation in mice at baseline and after administration of the anorectic drug fenfluramine.<h4>Results</h4>5-HTT overexpressing mice were both lighter and shorter than their wildtype littermates. Despite this size difference, food intake by transgenic and wildtype mice did not differ. There was no effect of genotype on the BSS or on food intake during the test at baseline. Increasing doses of fenfluramine reduced food intake in a similar manner in both transgenic and wildtype mice. After 0.3 and 1 mg/kg fenfluramine, the temporal pattern of the BSS was the same for both groups, whereas 3 and 10 mg/kg fenfluramine disrupted the BSS. In transgenic mice, this disruption was evident at the 3 mg/kg dose, while in wildtypes, it emerged only at the 10-mg/kg dose.<h4>Conclusion</h4>These data suggest that overexpression of the 5-HTT does not lead to alterations in feeding or satiety in food-deprived mice but does increase the occurrence of other non-feeding behaviours in response to the 5-HT releasing agent fenfluramine.

Also flagged:Aicardi-Goutières syndromeSystemic Lupus ErythematosusSLEFamilial Chilblain LupusRetinal Vasculopathy and Cerebral LeukodystrophyHereditary Vascular Retinopathy
Journal Article 2008-06-16 No Snippets Kavanagh D, Spitzer D, Kothari PH, Shaikh A, Liszewski MK, Richards A, Atkinson JP.
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Aicardi-Goutières syndrome (AGS), Systemic Lupus Erythematosus (SLE), Familial Chilblain Lupus (FCL) and Retinal Vasculopathy and Cerebral Leukodystrophy (RVCL) {a new term encompassing three independently described conditions with a common etiology--Cerebroretinal Vasculopathy (CRV), Hereditary Vascular Retinopathy (HVR) and Hereditary Endotheliopathy, Retinopathy and Nephropathy (HERNS)}--have previously been regarded as distinct entities. However, recent genetic analysis has demonstrated that each of these diseases maps to chromosome 3p21 and can be caused by mutations in TREX1, the major human 3'-5' exonuclease. In this review, we discuss the putative functions of TREX1 in relationship to the clinical, genetic and functional characteristics of each of these conditions.

Also flagged:Deathmultiple organ failurehemorrhagic shockliver injuryIL-6injury
Journal Article 2008-06-15 No Snippets Moran A, Akcan Arikan A, Mastrangelo MA, Wu Y, Yu B, Poli V, Tweardy DJ.
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Trauma is a major cause of mortality in the United States. Death among those surviving the initial insult is caused by multiple organ failure (MOF) with the liver among the organs most frequently affected. We previously demonstrated in rodents that trauma complicated by hemorrhagic shock (trauma/HS) results in liver injury that can be prevented by IL-6 administration at the start of resuscitation; however, the contribution of the severity of HS to the extent of liver injury, whether or not resuscitation is required and the mechanism for the IL-6 protective effect have not been reported. In the experiments reported here, we demonstrated that the extent of liver apoptosis induced by trauma/HS depends on the duration of hypotension and requires resuscitation. We established that IL-6 administration at the start of resuscitation is capable of completely reversing liver apoptosis and is associated with increased Stat3 activation. Microarray analysis of the livers showed that the main effect of IL-6 was to normalize the trauma/HS-induced apoptosis transcriptome. Pharmacological inhibition of Stat3 activity within the liver blocked the ability of IL-6 to prevent liver apoptosis and to normalize the trauma/HS- induced liver apoptosis transcriptome. Genetic deletion of a Stat3beta, a naturally occurring, dominant-negative isoform of the Stat3, attenuated trauma/HS-induced liver apoptosis, confirming a role for Stat3, especially Stat3alpha, in preventing trauma/HS-mediated liver apoptosis. Thus, trauma/HS-induced liver apoptosis depends on the duration of hypotension and requires resuscitation. IL-6 administration at the start of resuscitation reverses HS-induced liver apoptosis, through activation of Stat3alpha, which normalizes the trauma/HS-induced liver apoptosis transcriptome.

Also flagged:amino acidbindingpost-translational modificationslocalizationGene Expressionneurodegenerative disorders
Journal Article 2008-06-13 No Snippets Pattin KA, Moore JH.
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One of the central goals of human genetics is the identification of loci with alleles or genotypes that confer increased susceptibility. The availability of dense maps of single-nucleotide polymorphisms (SNPs) along with high-throughput genotyping technologies has set the stage for routine genome-wide association studies that are expected to significantly improve our ability to identify susceptibility loci. Before this promise can be realized, there are some significant challenges that need to be addressed. We address here the challenge of detecting epistasis or gene-gene interactions in genome-wide association studies. Discovering epistatic interactions in high dimensional datasets remains a challenge due to the computational complexity resulting from the analysis of all possible combinations of SNPs. One potential way to overcome the computational burden of a genome-wide epistasis analysis would be to devise a logical way to prioritize the many SNPs in a dataset so that the data may be analyzed more efficiently and yet still retain important biological information. One of the strongest demonstrations of the functional relationship between genes is protein-protein interaction. Thus, it is plausible that the expert knowledge extracted from protein interaction databases may allow for a more efficient analysis of genome-wide studies as well as facilitate the biological interpretation of the data. In this review we will discuss the challenges of detecting epistasis in genome-wide genetic studies and the means by which we propose to apply expert knowledge extracted from protein interaction databases to facilitate this process. We explore some of the fundamentals of protein interactions and the databases that are publicly available.

Also flagged:integrasetranscriptional regulatorsproviruschromatintranscription factorstranslational regulation factors
Journal Article 2008-06-13 ✓ 4 Snippets Studamire B, Goff SP.
In-Text Gene Mentions

…interacting protein (Enx-1,ABT1, TIF3, B-ATF, AF9,…

…Ku70, PRC, Baz2b,ABT1, SF3a3, U5snRNP, Kif3A,…

…Ku70, PRC andABT1, as was observed…

…Brd2, Enx-1, andABT1interacted with the…

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<h4>Background</h4>A critical step for retroviral replication is the stable integration of the provirus into the genome of its host. The viral integrase protein is key in this essential step of the retroviral life cycle. Although the basic mechanism of integration by mammalian retroviruses has been well characterized, the factors determining how viral integration events are targeted to particular regions of the genome or to regions of a particular DNA structure remain poorly defined. Significant questions remain regarding the influence of host proteins on the selection of target sites, on the repair of integration intermediates, and on the efficiency of integration.<h4>Results</h4>We describe the results of a yeast two-hybrid screen using Moloney murine leukemia virus integrase as bait to screen murine cDNA libraries for host proteins that interact with the integrase. We identified 27 proteins that interacted with different integrase fusion proteins. The identified proteins include chromatin remodeling, DNA repair and transcription factors (13 proteins); translational regulation factors, helicases, splicing factors and other RNA binding proteins (10 proteins); and transporters or miscellaneous factors (4 proteins). We confirmed the interaction of these proteins with integrase by testing them in the context of other yeast strains with GAL4-DNA binding domain-integrase fusions, and by in vitro binding assays between recombinant proteins. Subsequent analyses revealed that a number of the proteins identified as Mo-MLV integrase interactors also interact with HIV-1 integrase both in yeast and in vitro.<h4>Conclusion</h4>We identify several proteins interacting directly with both MoMLV and HIV-1 integrases that may be common to the integration reaction pathways of both viruses. Many of the proteins identified in the screen are logical interaction partners for integrase, and the validity of a number of the interactions are supported by other studies. In addition, we observe that some of the proteins have documented interactions with other viruses, raising the intriguing possibility that there may be common host proteins used by different viruses. We undertook this screen to identify host factors that might affect integration target site selection, and find that our screens have generated a wealth of putative interacting proteins that merit further investigation.

Also flagged:deathcoronary heart diseasestrokediabetesironalanine aminotransferase
Journal Article 2008-06-13 ✓ 5 Snippets Pankow JS, Boerwinkle E, Adams PC, Guallar E, Leiendecker-Foster C, Rogowski J, Eckfeldt JH.
In-Text Gene Mentions

C282Y homozygotes had significantly lower mean low-density lipoprotein (LDL) cholesterol and fibrinogen as well as higher mean levels of iron (ferritin, transferrin saturation) and liver biomarkers (alanine aminotransferase, Hepascore) compared with HFE wild-type subjects.

HFE C282Y homozygotes have reduced low-density lipoprotein cholesterol: the Atherosclerosis Risk in Communities (ARIC) Study.

We examined cardiovascular disease risk factors and iron and liver biomarkers, as well as morbidity and mortality associated with the C282Y and H63D variants of HFE in the Atherosclerosis Risk in Communities (ARIC) study, which is a population-based cohort of nearly 16,000 U.S. white and black men and women who were 45-64 years old at baseline.

HFEC282Y homozygotes have…

…mutations in theHFEgene, although previous…

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Recent studies have raised questions about the long-term health risks for individuals with mutations in the HFE gene, although previous studies may have been plagued by selection bias or lack of population-based comparison groups. We examined cardiovascular disease risk factors and iron and liver biomarkers, as well as morbidity and mortality associated with the C282Y and H63D variants of HFE in the Atherosclerosis Risk in Communities (ARIC) study, which is a population-based cohort of nearly 16,000 U.S. white and black men and women who were 45-64 years old at baseline. Subjects were followed for an average of 15 years for death, incident coronary heart disease, stroke, and heart failure, and an average of 8 years for incident diabetes. The prevalence of C282Y homozygosity was 0.42% (45/10,800) in whites, which is similar to other North American population-based studies. C282Y homozygotes had significantly lower mean low-density lipoprotein (LDL) cholesterol and fibrinogen as well as higher mean levels of iron (ferritin, transferrin saturation) and liver biomarkers (alanine aminotransferase, Hepascore) compared with HFE wild-type subjects. Rates of all-cause mortality, cardiovascular disease, and diabetes were similar across HFE genotypes. These prospective, population-based data indicate higher serum iron indices and possible mild liver dysfunction or disease in some C282Y homozygotes, but they provide little evidence that HFE C282Y or H63D mutations are related to all-cause mortality, cardiovascular disease, or diabetes. Reduced LDL in C282Y homozygotes may be because of effects of excess iron on cholesterol metabolism and lipoprotein formation in the liver.

Also flagged:sigma-1 receptorcocainesteroidpeptidesteroid binding domain-like Ibinding
Journal Article 2008-06-12 No Snippets Fontanilla D, Hajipour AR, Pal A, Chu UB, Arbabian M, Ruoho AE.
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Radioiodinated photoactivatable photoprobes can provide valuable insights regarding protein structure. Previous work in our laboratory showed that the cocaine derivative and photoprobe 3-[ (125)I]iodo-4-azidococaine ([ (125)I]IACoc) binds to the sigma-1 receptor with 2-3 orders of magnitude higher affinity than cocaine [Kahoun, J. R. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 1393-1397]. Using this photoprobe, we demonstrated the insertion site for [ (125)I]IACoc to be Asp188 [Chen, Y. (2007) Biochemistry 46, 3532-3542], which resides in the proposed steroid binding domain-like II (SBDLII) region (amino acids 176-194) [Pal, A. (2007) Mol. Pharmacol. 72, 921-933]. An additional photoprobe based on the sigma-1 receptor ligand fenpropimorph, 1- N-(2-3-[ (125)I]iodophenyl)propane ([ (125)I]IAF), was found to label a peptide in both the SBDLII and steroid binding domain-like I (SBDLI) (amino acids 91-109) [Pal, A. (2007) Mol. Pharmacol. 72, 921-933]. In this report, we describe two novel strategically positioned carrier-free, radioiodinated photoaffinity labels specifically designed to probe the putative "nitrogen interacting region" of sigma-1 receptor ligands. These two novel photoprobes are (-)-methyl 3-(benzoyloxy)-8-2-(4-azido-3-[ (125)I]iodobenzene)-1-ethyl-8-azabicyclo[3.2.1]octane-2-carboxylate ([ (125)I]-N-IACoc) and N-propyl- N-(4-azido-3-iodophenylethyl)-3-(4-fluorophenyl)propylamine ([ (125)I]IAC44). In addition to reporting their binding affinities to the sigma-1 and sigma-2 receptors, we show that both photoaffinity labels specifically and covalently derivatized the pure guinea pig sigma-1 receptor (26.1 kDa) [Ramachandran, S. (2007) Protein Expression Purif. 51, 283-292]. Cleavage of the photolabeled sigma-1 receptor using Endo Lys C and cyanogen bromide (CNBr) revealed that the [ (125)I]-N-IACoc label was located primarily in the N-terminus and SBDLI-containing peptides of the sigma-1 receptor, while [ (125)I]IAC44 was found in peptide fragments consistent with labeling of both SBDLI and SBDLII.

Also flagged:EGFRKRASNSCLCchromosomeadenocarcinomastumors
Journal Article 2008-06-12 ✓ 5 Snippets Blons H, Pallier K, Le Corre D, Danel C, Tremblay-Gravel M, Houdayer C, Fabre-Guillevin E, Riquet M, Dessen P, Laurent-Puig P.
In-Text Gene Mentions

Homozygous deletions at DCC, DSG2 and DSC3 as well as copy number changes of the HDAC9, TWIST1 and ITGB8 region were validated by real time PCR for the 24 tumors screened by SNP array.

The 9p21.1 locus contains CDKN2A and the 18q21.1 contains DCC, both are well known tumor suppressors.

For the 24 tumors, quantitative PCR was ran to estimated gene copy number at CDKN2A, DSG3, DSC2 and DCC and validated the results of the SNP Array (see Additional file 4).

But new regions of homozygous deletion have been found in EGFR mutated tumors especially at 18q involving the DCC gene and a cluster of desmosomal proteins.

…Homozygous deletions atDCC, DSG2 and…

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<h4>Background</h4>Lung cancer with EGFR mutation was shown to be a specific clinical entity. In order to better understand the biology behind this disease we used a genome wide characterization of loss of heterozygosity and amplification by Single Nucleotide Polymorphism (SNP) Array analysis to point out chromosome segments linked to EGFR mutations. To do so, we compared genetic profiles between EGFR mutated adenocarcinomas (ADC) and KRAS mutated ADC from 24 women with localized lung cancer.<h4>Results</h4>Patterns of alterations were different between EGFR and KRAS mutated tumors and specific chromosomes alterations were linked to the EGFR mutated group. Indeed chromosome regions 14q21.3 (p = 0.027), 7p21.3-p21.2 (p = 0.032), 7p21.3 (p = 0.042) and 7p21.2-7p15.3 (p = 0.043) were found significantly amplified in EGFR mutated tumors. Within those regions 3 genes are of special interest ITGB8, HDAC9 and TWIST1. Moreover, homozygous deletions at CDKN2A and LOH at RB1 were identified in EGFR mutated tumors. We therefore tested the existence of a link between EGFR mutation, CDKN2A homozygous deletion and cyclin amplification in a larger series of tumors. Indeed, in a series of non-small-cell lung carcinoma (n = 98) we showed that homozygous deletions at CDKN2A were linked to EGFR mutations and absence of smoking whereas cyclin amplifications (CCNE1 and CCND1) were associated to TP53 mutations and smoking habit.<h4>Conclusion</h4>All together, our results show that genome wide patterns of alteration differ between EGFR and KRAS mutated lung ADC, describe two models of oncogenic cooperation involving either EGFR mutation and CDKN2A deletion or cyclin amplification and TP53 inactivating mutations and identified new chromosome regions at 7p and 14q associated to EGFR mutations in lung cancer.

Also flagged:lectinsantimicrobial peptidesoxygenbindingS. mansoni infectiondefense responses
Journal Article 2008-06-12 No Snippets Hanelt B, Lun CM, Adema CM.
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The snail Biomphalaria glabrata (Gastropoda, Mollusca) is an important intermediate host for the human parasite Schistosoma mansoni (Digenea, Trematoda). Anti-pathogen responses of B. glabrata were studied towards a better understanding of snail immunity and host-parasite compatibility. Open reading frame ESTs (ORESTES) were sampled from different transcriptomes of M line strain B. glabrata, 12h post-challenge with Escherichia coli (Gram-negative), Micrococcus luteus (Gram-positive) bacteria or compatible S. mansoni, and controls. The resulting 3123 ORESTES represented 2129 unique sequences (373 clusters, 1756 singletons). Of these, 175 (8.1%) were putative defense factors, including lectins, antimicrobial peptides and components of various immune-effector systems. Comparison of biological processes (GO-terms) within different transcriptomes indicated that B. glabrata increased oxygen transport and metal binding in reaction to all challenges. Comprehensive comparisons of transcriptomes revealed that responses of B. glabrata against bacteria were similar to each other and differed from the ineffective response to S. mansoni. Furthermore, the response to S. mansoni infection was less comprehensive than that to bacteria. Many novel (unknown) sequences were recovered in association with particular challenges. B. glabrata possesses multi-faceted, potent immune defenses. This agrees with the notion that S. mansoni is capable of immune-evasion and prevents effective host defense responses in order to survive in B. glabrata. Future analysis of the numerous unknown sequences recovered from challenged snails may reveal novel immune factors and provide increased understanding of immunity of B. glabrata in relation to parasite-host compatibility.

Also flagged:Synthesisdipeptidyl peptidase IVPalkeypyrrolidinechloroacetyl
Journal Article 2008-06-12 No Snippets Singh SK, Manne N, Pal M.
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An alternative and practical synthesis of (S)-1-(2-chloroacetyl)pyrrolidine-2-carbonitrile was achieved. Reaction of L-proline with chloroacetyl chloride was followed by conversion of the carboxylic acid moiety of the resulting N-acylated product into the carbonitrile via the corresponding amide intermediate. The synthesized pyrrolidine derivative was utilized to prepare DPP-IV inhibitor Vildagliptin.

Also flagged:Respiratory epithelial adenomatoid hamartomatumorsinverted papillomasinonasal carcinomaRespiratoryAdenomatoid Hamartoma
Journal Article 2008-06-12 ✓ 1 Snippet Fitzhugh VA, Mirani N.
In-Text Gene Mentions

DCC

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Respiratory epithelial adenomatoid hamartoma (REAH) is an uncommon lesion of the upper aerodigestive tract first described by Wenig and Heffner in 1995 as prominent glandular proliferations lined by ciliated respiratory epithelium originating from the surface epithelium. The entity is seen most often in male adults. Clinically the lesion presents as a polypoid mass, often in one or both nasal cavities, though other locations have been described. While REAH is benign, awareness and recognition of the lesion is important because it can be easily confused grossly and microscopically with more threatening tumors such as inverted papilloma and sinonasal carcinoma. The literature of REAH is reviewed with detail paid to the histologic diagnosis. The clinical presentation, radiologic findings, and differential diagnosis are also described.

Also flagged:DysDystrophinMod20EGFDystroglycan-DystrophinDg-Dys
Journal Article 2008-06-11 ✓ 1 Snippet Kucherenko MM, Pantoja M, Yatsenko AS, Shcherbata HR, Fischer KA, Maksymiv DV, Chernyk YI, Ruohola-Baker H.
In-Text Gene Mentions

…and Netrin Receptor (DCC) pathways have previously…

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The Dystroglycan-Dystrophin (Dg-Dys) complex has a capacity to transmit information from the extracellular matrix to the cytoskeleton inside the cell. It is proposed that this interaction is under tight regulation; however the signaling/regulatory components of Dg-Dys complex remain elusive. Understanding the regulation of the complex is critical since defects in this complex cause muscular dystrophy in humans. To reveal new regulators of the Dg-Dys complex, we used a model organism Drosophila melanogaster and performed genetic interaction screens to identify modifiers of Dg and Dys mutants in Drosophila wing veins. These mutant screens revealed that the Dg-Dys complex interacts with genes involved in muscle function and components of Notch, TGF-beta and EGFR signaling pathways. In addition, components of pathways that are required for cellular and/or axonal migration through cytoskeletal regulation, such as Semaphorin-Plexin, Frazzled-Netrin and Slit-Robo pathways show interactions with Dys and/or Dg. These data suggest that the Dg-Dys complex and the other pathways regulating extracellular information transfer to the cytoskeletal dynamics are more intercalated than previously thought.

Also flagged:Matriptasetype 2 transmembrane serine proteasecarcinomahepatocyte growth factor activator inhibitor 1HAI-1membrane
Journal Article 2008-06-11 ✓ 1 Snippet Tseng IC, Chou FP, Su SF, Oberst M, Madayiputhiya N, Lee MS, Lee MS, Wang JK, Sloane DE, Johnson M, Lin CY.
In-Text Gene Mentions

ATIII

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Matriptase, a type 2 transmembrane serine protease, is predominately expressed by epithelial and carcinoma cells in which hepatocyte growth factor activator inhibitor 1 (HAI-1), a membrane-bound, Kunitz-type serine protease inhibitor, is also expressed. HAI-1 plays dual roles in the regulation of matriptase, as a conventional protease inhibitor and as a factor required for zymogen activation of matriptase. As a consequence, activation of matriptase is immediately followed by HAI-1-mediated inhibition, with the activated matriptase being sequestered into HAI-1 complexes. Matriptase is also expressed by peripheral blood leukocytes, such as monocytes and macrophages; however, in contrast to epithelial cells, monocytes and macrophages were reported not to express HAI-1, suggesting that these leukocytes possess alternate, HAI-1-independent mechanisms regulating the zymogen activation and protease inhibition of matriptase. In the present study, we characterized matriptase complexes of 110 kDa in human milk, which contained no HAI-1 and resisted dissociation in boiling SDS in the absence of reducing agents. These complexes were further purified and dissociated into 80-kDa and 45-kDa fragments by treatment with reducing agents. Proteomic and immunological methods identified the 45-kDa fragment as the noncatalytic domains of matriptase and the 80-kDa fragment as the matriptase serine protease domain covalently linked to one of three different secreted serpin inhibitors: antithrombin III, alpha1-antitrypsin, and alpha2-antiplasmin. Identification of matriptase-serpin inhibitor complexes provides evidence for the first time that the proteolytic activity of matriptase, from those cells that express no or low levels of HAI-1, may be controlled by secreted serpins.

Also flagged:ferredoxincarbazolecarbazole 1,9a-dioxygenaseCARDOdioxygenasedegradation
Journal Article 2008-06-11 No Snippets Umeda T, Katsuki J, Usami Y, Inoue K, Noguchi H, Fujimoto Z, Ashikawa Y, Yamane H, Nojiri H.
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Novosphingobium sp. KA1 uses carbazole 1,9a-dioxygenase (CARDO) as the first dioxygenase in its carbazole-degradation pathway. The CARDO of KA1 contains a terminal oxygenase component and two electron-transfer components: ferredoxin and ferredoxin reductase. In contrast to the CARDO systems of other species, the ferredoxin component of KA1 is a putidaredoxin-type protein. This novel ferredoxin was crystallized at 293 K by the hanging-drop vapour-diffusion method using PEG MME 550 as the precipitant under anaerobic conditions. The crystals belong to space group C222(1) and diffraction data were collected to a resolution of 1.9 A (the diffraction limit was 1.6 A).

Also flagged:haemochromatosischromosomes
Journal Article 2008-06-10 ✓ 3 Snippets Pedersen P, Melsen GV, Milman N.
In-Text Gene Mentions

…the haemochromatosis gene (HFE) variants C282Y, H63D…

…quencies of haemochromatosis (HFE) gene mutations or…

…was screened forHFEC282Y (c845G-->A), H63D…

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The objective was to assess the frequencies of haemochromatosis (HFE) gene mutations or variants C282Y, H63D and S65C in ethnic Danes. This is a prospective epidemiologic population study. A cohort of 6,020 Danish men aged 30-50 years was screened for HFE C282Y (c845G-->A), H63D (c187C-->G) and S65C (c193A-->T) gene variants, assessed on saliva or blood samples by restriction fragment length polymorphism (RFLP) analysis. The C282Y gene variant allele was present in 5.6%, H63D in 12.8% and S65C in 1.8% of the chromosomes. In the entire series, we observed 1.4% H63D/C282Y, 0.1% S65C/C282Y and 0.4% H63D/S65C compound heterozygotes. The C282Y allele frequency in Denmark is of similar order as reported in other Scandinavian countries: Iceland 5.1%, Faeroe Islands 6.6%, Norway 6.8% and Sweden 5.8%. Also, the H63D frequency in Denmark is close to the frequencies in other Scandinavian countries: Iceland 10.9%, Faeroe Islands 15.2%, Norway 11.4% and Sweden 12.1%.

Also flagged:metabolismbone formationfluoridepositronmineralizationhydroxyl
Journal Article 2008-06-10 No Snippets Temmerman OP, Raijmakers PG, Heyligers IC, Comans EF, Lubberink M, Teule GJ, Lammertsma AA.
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<h4>Purpose</h4>To evaluate bone blood flow and bone formation in patients after total hip revision surgery with impacted bone grafting using H2 15O and [18F]fluoride positron emission tomography (PET).<h4>Procedures</h4>To asses bone blood flow and bone metabolism in bone allograft after impaction grafting, four patients treated with total hip revision surgery were enrolled prospectively in this study. Six patients scheduled for primary hip arthroplasties were included as a control group. The study protocol consisted of three H2 15O and [18F]fluoride PET scans in each patient.<h4>Results</h4>Bone blood flow increased significantly compared to the preoperative state in patients treated for primary hip arthroplasty. In patients undergoing revision surgery, bone blood flow was twofold to threefold higher compared to the preoperative state, but did not reach significance. Bone metabolism in patients undergoing revision was threefold higher 2 weeks postoperatively compared to the primary hip group. We found a significant correlation between Ki and bone blood flow.<h4>Conclusions</h4>Allogeneic bone grafts induce a higher rate of local periprosthetic bone formation compared to periprosthetic bone formation after a primary total hip placement. In vivo coupling between bone blood flow and bone metabolism suggests that bone metabolism in allogeneic bone grafts may partly rely on bone blood flow adaptations.

Also flagged:transcription factorbindingGene Expressiontissue developmenttranscription factorscancer
Journal Article 2008-06-09 ✓ 1 Snippet Liu X, Yu X, Zack DJ, Zhu H, Qian J.
In-Text Gene Mentions

…between FOXJ2 andPOU3F2, with a p-value…

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<h4>Background</h4>Understanding how genes are expressed and regulated in different tissues is a fundamental and challenging question. However, most of currently available biological databases do not focus on tissue-specific gene regulation.<h4>Results</h4>The recent development of computational methods for tissue-specific combinational gene regulation, based on transcription factor binding sites, enables us to perform a large-scale analysis of tissue-specific gene regulation in human tissues. The results are stored in a web database called TiGER (Tissue-specific Gene Expression and Regulation). The database contains three types of data including tissue-specific gene expression profiles, combinatorial gene regulations, and cis-regulatory module (CRM) detections. At present the database contains expression profiles for 19,526 UniGene genes, combinatorial regulations for 7,341 transcription factor pairs and 6,232 putative CRMs for 2,130 RefSeq genes.<h4>Conclusion</h4>We have developed and made publicly available a database, TiGER, which summarizes and provides large scale data sets for tissue-specific gene expression and regulation in a variety of human tissues. This resource is available at 1.

Also flagged:tumorsironmetabolismTrf2hepatocellular carcinomatransferrin receptor 2
Journal Article 2008-06-09 ✓ 2 Snippets Kijima H, Sawada T, Tomosugi N, Kubota K.
In-Text Gene Mentions

…iron overload disorder,hemochromatosis, but also with…

…of patients withhemochromatosis[ 18 ].…

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<h4>Background</h4>The present study evaluated the expression of hepcidin mRNA in hepatocellular carcinoma (HCC).<h4>Methods</h4>Samples of cancerous and non-cancerous liver tissue were taken from 40 patients with HCC who underwent hepatectomy. Expression of hepcidin mRNA was evaluated by real-time PCR, and compared in tumors differing in their degree of differentiation, number of tumors, and vessel invasion. Correlations between hepcidin expression and the interval until HCC recurrence, and the serum concentration of hepcidin were evaluated, together with the expression of mRNAs for other iron metabolism molecules, ferroportin and transferrin receptor 2 (Trf2).<h4>Results</h4>Hepcidin mRNA expression in non-cancerous and cancerous tissues was 1891.8 (32.3-23187.4) and 53.4 (1.9-3185.8), respectively (P < 0.0001). There were no significant differences in hepcidin expression among tumors differing in their degree of differentiation, number of tumors, or vessel invasion. There was no significant correlation between hepcidin expression and the interval until HCC recurrence. The serum concentration of hepcidin-25 was not correlated with hepcidin-mRNA expression. Finally, there were no significant differences in the expression of mRNA for ferroportin and Trf2 between cancerous and non-cancerous tissues.<h4>Conclusion</h4>Expression of hepcidin mRNA is strikingly suppressed in cancerous, but not in non-cancerous tissues, in patients with HCC, irrespective of ferroportin or Trf2 expression. Uniform suppression of hepcidin may be linked to the development of HCC.

Also flagged:Timothy syndromeCa(2+) channelmultisystembindingG-protein
Journal Article 2008-06-07 No Snippets Cens T, Leyris JP, Charnet P.
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The Timothy syndrome is a multisystem disorder associated with the mutation of a Gly residue (G402 or G406) in the Ca(v)1.2 Ca(2+) channel. G406 is localized at the end of the IS6 segment and just before the intracellular I-II loop, which is important for the regulation of channel inactivation and the binding of the Ca(v)beta subunit. This Gly residue is conserved in all Ca(v)1 and Ca(v)2 channels, and the G to R exchange produces a strong decrease of inactivation not only in Ca(v)1.2 but also in Ca(v)2.3. Here, we show that the mutation into Arg or Glu of the homologous Gly residue in Ca(v)2.1 (G363) produces also a slowing of inactivation. However, the G-to-A exchange that decreases the inactivation rate in Ca(v)1.2 and Ca(v)2.3 increases inactivation in Ca(v)2.1. Each mutation affects specifically the gating properties of Ca(v)2.1 that remain nevertheless modulated by the co-expressed beta subunit as with wild-type channel. The strong decrease of inactivation produced by the G363R or G363E mutations was reminiscent to that previously described for a specific splice variant of Ca(v)2.1 that contains a single Val residue inserted in the I-II loop (V421). We unexpectedly found that the V421 insertion does not affect the inactivation rate of Ca(v)2.1 and that the effects previously attributed to this insertion, including those on G-protein regulation, can be reproduced by the G363E mutation. Altogether, our results highlight the role of G363 in gating properties, inactivation kinetics, and G-protein regulation of Ca(v)2.1 and the lack of effect of V421 insertion on inactivation.

Also flagged:silibinincell growthhepatocellular carcinomaextracellular signal-regulated kinase 1phosphorylationtetrazolium
Journal Article 2008-06-07 No Snippets Momeny M, Khorramizadeh MR, Ghaffari SH, Yousefi M, Yekaninejad MS, Esmaeili R, Jahanshiri Z, Nooridaloii MR.
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The purpose of the current study is to evaluate the effect of silibinin on human hepatocellular carcinoma HepG-2 cells. Microculture tetrazolium test (MTT assay), Lactate dehydrogenase (LDH) release, Gelatin zymography, Griess reaction, Cell-based the extracelluar signal-regulated kinase (ERK) 1/2 phosphorylation assay and quantitative real-time RT-PCR were employed to appraise the effect of silibinin on cell proliferation, cytotoxicity, metastatic potential, nitric oxide (NO) production, ERK 1/2 phosphorylation and activation in HepG-2 cells. Silibinin inhibited cell proliferation, matrix metalloproteinase 2 enzymatic activity, NO production and ERK 1/2 phosphorylation in a dose-dependent manner without exerting any cytotoxicity effect. In addition, an expressive increase in mRNA levels of Raf kinase inhibitor protein (RKIP), sprouty-related protein 1 with EVH-1 domain (Spred-1), sprouty-related protein with EVH-1 domain 2 (Spred-2) coupled with a significant reduction in transcriptional levels of highly expressed in cancer (Hec1) and MMP-2 were observed. Altogether, these issues show for the first time that silibinin treatment could inhibit cell proliferation and invasive potential of HepG-2 cells through inhibition of ERK 1/2 cascade both directly (through suppression of ERK 1/2 phosphorylation) and indirectly (through up-regulation of RKIP, Spred-1 and Spred-2). In addition, cell growth and proliferation may be inhibited by silibinin through down-regulation of Hec1.

Also flagged:transcription factorschromatinorganizationRNA polymerase IIPol IIMediator
Journal Article 2008-06-06 No Snippets Hahn S.
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No abstract available.

Also flagged:Prdm1transcription factortranscriptional repressorgene expressiontranscriptionalsarcomeric proteins
Journal Article 2008-06-06 ✓ 5 Snippets von Hofsten J, Elworthy S, Gilchrist MJ, Smith JC, Wardle FC, Ingham PW.
In-Text Gene Mentions

…Prdm1- andSox6-mediated transcriptional repr…

…the transcriptional repressorSox6.…

…Thesox6translation targeted morpholin…

…and the completesox6cds ( EU532205…

…, fMyHCx ,sox6and stnnC (subcloned…

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The zebrafish u-boot (ubo) gene encodes the transcription factor Prdm1, which is essential for the specification of the primary slow-twitch muscle fibres that derive from adaxial cells. Here, we show that Prdm1 functions by acting as a transcriptional repressor and that slow-twitch-specific muscle gene expression is activated by Prdm1-mediated repression of the transcriptional repressor Sox6. Genes encoding fast-specific isoforms of sarcomeric proteins are ectopically expressed in the adaxial cells of ubo(tp39) mutant embryos. By using chromatin immunoprecipitation, we show that these are direct targets of Prdm1. Thus, Prdm1 promotes slow-twitch fibre differentiation by acting as a global repressor of fast-fibre-specific genes, as well as by abrogating the repression of slow-fibre-specific genes.

Also flagged:gene expressionextracellular matrix collagenproteoglycanbiglycanextracellular matrix collagensproteoglycans
Journal Article 2008-06-06 ✓ 5 Snippets Wu F, Lee S, Schumacher M, Jun A, Chakravarti S.
In-Text Gene Mentions

Akr1b7, Prdx6), inflammation

Dhcr24, Cdo1, Akr1b7, Prdx6), inflammation

Cdo1, Akr1b7, Prdx6), inflammation

…Dhcr24, Cdo1, Akr1b7,Prdx6), inflammation (…

Prdx6

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The cornea continues to mature after birth to develop a fully functional, refractive and protective barrier tissue. Here we investigated the complex biological events underlying this process by profiling global genome-wide gene expression patterns of the immature postnatal day 10 and 7-week old adult mouse cornea. The lens and tendon were included in the study to increase the specificity of genes identified as upregulated in the corneal samples. Notable similarities in gene expression between the cornea and the tendon were in the mesenchymal extracellular matrix collagen (types I, III, V, VI) and proteoglycan (lumican, decorin and biglycan) genes. Expression similarities in the cornea and lens were limited to certain epithelial genes and the crystallins. Approximately 76 genes were over expressed in the cornea samples that showed basal expression levels in the lens and tendon. Thirty-two of these were novel with no known functions in the cornea. These include genes with a potential role in protection against oxidative stress (Dhcr24, Cdo1, Akr1b7, Prdx6), inflammation (Ltb4dh, Wdr1), ion transport (Pdzk1ip1, Slc12a2, Slc25a17) and transcription (Zfp36l3, Pdzk1ip1). Direct comparison of the cornea of two ages showed selective upregulation of 50 and 12 genes in the P10 and adult cornea, respectively. Of the upregulated P10 genes several encode extracellular matrix collagens and proteoglycans that are stable components of the adult cornea and their high transcriptional activity at P10 indicate a period of actie corneal growth and matrix deposition in the young cornea. Much less is known about the genes selectively over expressed in the adult cornea; some relate to immune response and innervations (Npy), and possibly to electron transport (Cyp24a1, Cyp2f2) and others of yet unknown functions in the cornea (Rgs10, Psmb8, Xlr4). This study detected expression of genes with known functions in the cornea, providing additional validation of the microarray experiments. Importantly, it identified several novel genes whose functions have not been investigated in the cornea.

Also flagged:Warfarinvitamin K epoxide reductase complex 1CYP2C9VKORC1cytochrome P450 2C9vitamin K
Journal Article 2008-06-05 No Snippets Cooper GM, Johnson JA, Langaee TY, Feng H, Stanaway IB, Schwarz UI, Ritchie MD, Stein CM, Roden DM, Smith JD, Veenstra DL, Rettie AE, Rieder MJ.
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Warfarin dosing is correlated with polymorphisms in vitamin K epoxide reductase complex 1 (VKORC1) and the cytochrome P450 2C9 (CYP2C9) genes. Recently, the FDA revised warfarin labeling to raise physician awareness about these genetic effects. Randomized clinical trials are underway to test genetically based dosing algorithms. It is thus important to determine whether common single nucleotide polymorphisms (SNPs) in other gene(s) have a large effect on warfarin dosing. A retrospective genome-wide association study was designed to identify polymorphisms that could explain a large fraction of the dose variance. White patients from an index warfarin population (n = 181) and 2 independent replication patient populations (n = 374) were studied. From the approximately 550 000 polymorphisms tested, the most significant independent effect was associated with VKORC1 polymorphisms (P = 6.2 x 10(-13)) in the index patients. CYP2C9 (rs1057910 CYP2C9*3) and rs4917639) was associated with dose at moderate significance levels (P approximately 10(-4)). Replication polymorphisms (355 SNPs) from the index study did not show any significant effects in the replication patient sets. We conclude that common SNPs with large effects on warfarin dose are unlikely to be discovered outside of the CYP2C9 and VKORC1 genes. Randomized clinical trials that account for these 2 genes should therefore produce results that are definitive and broadly applicable.

Also flagged:Synthesisproteasomeglycyrrhetinic acidhydroxylcarboxylic acidglycyrrhizic acid
Journal Article 2008-06-05 No Snippets Huang L, Yu D, Ho P, Qian K, Lee KH, Chen CH.
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This study discovered that glycyrrhetinic acid inhibited the human 20S proteasome at 22.3microM. Esterification of the C-3 hydroxyl group on glycyrrhetinic acid with various carboxylic acid reagents yielded a series of analogs with marked improved potency. Among the derivatives, glycyrrhetinic acid 3-O-isophthalate (17) was the most potent compound with IC(50) of 0.22microM, which was approximately 100-fold more potent than glycyrrhetinic acid.

Also flagged:cell adhesion molecule Kilonsynapseimmunoglobulincell adhesion moleculesaxonspresynaptic terminals
Journal Article 2008-06-05 ✓ 5 Snippets Hashimoto T, Yamada M, Maekawa S, Nakashima T, Miyata S.
In-Text Gene Mentions

Kilonis a member…

…spatial changes ofKilonexpression and its…

Kilonwas observed to…

Kilonwas solubilized with…

…The overexpression ofKilongene using a…

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Kilon is a member of the IgLON family belonging to the immunoglobulin superfamily of cell adhesion molecules. In the present study, we investigated temporal and spatial changes of Kilon expression and its modulatory functions for synapse number using hippocampal cultured neurons. Kilon was observed to localize chiefly at axons and presynaptic terminals at early culture stage, however, it was seen mainly at dendritic postsynaptic spine of mature neurons at late culture stages. Kilon was solubilized with detergent treatment at early culture stages, while it resisted to extraction of the detergent in mature neurons. The overexpression of Kilon gene using a plasmid vector decreased the number of dendritic synapses at early culture stages, whereas the overexpression increased the number of dendritic synapses at late culture. These results demonstrate the alteration of modulatory function of Kilon for the number of dendritic synapses concomitant with changes in its localization and detergent solubility during neuronal culture development.

Also flagged:chronic hepatitis Cinterferonribavirinpolymerasepeginterferoninterferon alfa
Journal Article 2008-06-05 No Snippets Morgan TR, Lambrecht RW, Bonkovsky HL, Chung RT, Naishadham D, Sterling RK, Fontana RJ, Lee WM, Ghany MG, Wright EC, O'Brien TR, HALT-C Trial Group.
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<h4>Background/aims</h4>Certain host genetic polymorphisms reportedly affect the likelihood of a sustained virological response (SVR) to interferon treatment in subjects infected with hepatitis C virus (HCV). As part of the HALT-C trial we evaluated genetic associations among patients infected with HCV genotype 1 who had failed previous interferon treatment.<h4>Methods</h4>SVR was determined 24 weeks after completing treatment with pegylated interferon alfa-2a and ribavirin. Eight single nucleotide polymorphisms (SNPs) were selected on the basis of previously reported associations with treatment response. Genotypes were assessed by polymerase chain reaction-based assays. The percentage of patients who achieved SVR was determined for each genotype and for an IL10 promoter diplotype.<h4>Results</h4>Among 637 non-Hispanic Caucasian patients there were no significant associations between genotype for any individual SNP (IL10-1082, IL10-592, TNF-308, TNF-238, TGFB1 codon 25, CCL2-2518, EPHX1 codon 113 and AGT-6) and SVR, but SVR was more common among the patients who were homozygous for the ACC IL10 promoter diplotype (adjusted odds ratio, 3.24; 95% confidence interval, 1.33-7.78; p=0.001).<h4>Conclusions</h4>Among non-Hispanic Caucasian patients treated with peginterferon and ribavirin after failing previous treatment with interferon, homozygosity for the ACC IL10 promoter diplotype was associated with SVR.

Also flagged:transcription factorcardiac hypertrophyMyogene expressionNF-κBcell adhesion molecules
Journal Article 2008-06-05 ✓ 1 Snippet Young D, Popovic ZB, Jones WK, Gupta S.
In-Text Gene Mentions

PTGIS

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Nuclear factor-kappaB (NF-kappaB) is a ubiquitous transcription factor that regulates various kinds of genes including inflammatory molecules, macrophage infiltration factors, cell adhesion molecules, and so forth, in various disease processes including cardiac hypertrophy and heart failure. Previously, we have demonstrated that activation of NF-kappaB was required in myotrophin-induced cardiac hypertrophy, in spontaneously hypertensive rats, and in dilated cardiomyopathy human hearts. Moreover, our recent study using the myotrophin-overexpressed transgenic mouse (Myo-Tg) model showed that short hairpin RNA-mediated knockdown of NF-kappaB significantly attenuated cardiac mass associated with improved cardiac function. Although it has been shown that NF-kappaB is substantially involved in cardiovascular remodeling, it is not clear whether the continuous blockade of NF-kappaB is effective in cardiovascular remodeling. To address this question, we took a genetic approach using IkappaB alpha triple mutant mice (3M) bred with Myo-Tg mice (a progressive hypertrophy/heart failure model). The double transgenic mice (Myo-3M) displayed an attenuated cardiac hypertrophy (9.8+/-0.62 versus 5.4+/-0.34, p<0.001) and improved cardiac function associated with significant inhibition of the NF-kappaB signaling cascade, hypertrophy marker gene expression, and inflammatory and macrophage gene expression at 24 weeks of age compared to Myo-Tg mice. NF-kappaB-targeted gene array profiling displayed several important genes that were significantly downregulated in Myo-3M mice compared to Myo-Tg mice. Furthermore, Myo-3M did not show any changes of apoptotic gene expression, indicating that significant inhibition of NF-kappaB activation reduces further proinflammatory reactions without affecting susceptibility to apoptosis. Therefore, development of therapeutic strategies targeting NF-kappaB may provide an effective approach to prevent adverse cardiac pathophysiological consequences.

Also flagged:ironhereditary hemochromatosishepatomaSlc39a14metal transportertetracycline
Journal Article 2008-06-04 ✓ 5 Snippets Gao J, Zhao N, Knutson MD, Enns CA.
In-Text Gene Mentions

These results suggest that HFE decreases the stability of Zip14 and therefore reduces the iron loading in HepG2 cells.

To determine if HFE had a similar effect on Zip14 in another cell line, HeLa cells expressing HFE under the tetracycline-repressible promoter were transfected with Zip14.

In this study, we investigated the role of HFE in the regulation of both transferrin-bound iron (TBI) and non-transferrin-bound iron (NTBI) uptake in HepG2 cells, a human hepatoma cell line.

…itary hemochromatosis protein,HFE, inhibits iron uptake…

…itary hemochromatosis protein,HFE, causes iron overload…

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Lack of functional hereditary hemochromatosis protein, HFE, causes iron overload predominantly in hepatocytes, the major site of HFE expression in the liver. In this study, we investigated the role of HFE in the regulation of both transferrin-bound iron (TBI) and non-transferrin-bound iron (NTBI) uptake in HepG2 cells, a human hepatoma cell line. Expression of HFE decreased both TBI and NTBI uptake. It also resulted in a decrease in the protein levels of Zip14 with no evident change in the mRNA level of Zip14. Zip14 (Slc39a14) is a metal transporter that mediates NTBI into cells (Liuzzi, J. P., Aydemir, F., Nam, H., Knutson, M. D., and Cousins, R. J. (2006) Proc. Natl. Acad. Sci. U. S. A. 103, 13612-13617). Knockdown of Zip14 with siRNA abolished the effect of HFE on NTBI uptake. To determine if HFE had a similar effect on Zip14 in another cell line, HeLa cells expressing HFE under the tetracycline-repressible promoter were transfected with Zip14. As in HepG2 cells, HFE expression inhibited NTBI uptake by approximately 50% and decreased Zip14 protein levels. Further analysis of protein turnover indicated that the half-life of Zip14 is lower in cells that express HFE. These results suggest that HFE decreases the stability of Zip14 and therefore reduces the iron loading in HepG2 cells.

Also flagged:Penicillinerythromycinclindamycintetracyclinegentamicinantibodies
Journal Article 2008-06-04 No Snippets Vestrheim DF, Høiby EA, Aaberge IS, Caugant DA.
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A cross-sectional study of nasopharyngeal colonization with Streptococcus pneumoniae was performed among 573 children attending 29 day-care centers (DCCs) in Norway prior to the start of mass vaccination with the heptavalent pneumococcal conjugate vaccine (PCV-7). A sensitive sampling method was employed, including transport in an enrichment broth and serotyping of pneumococci directly from the broth, in addition to traditional single-colony isolation from blood agar plates. The prevalence of carriage was high, peaking at 88.7% in 2-year-olds. More than one serotype was isolated from 12.7% of the carriers. Of 509 isolates obtained, 227 (44.6%) belonged to the PCV-7 serotypes. Penicillin nonsusceptibility was rare (1.8% of the isolates). Nonsusceptibility to erythromycin (5.9%), clindamycin (2.0%), and tetracycline (5.5%) was associated with PCV-7 serotypes (P < 0.001). Multilocus sequence typing was performed on the whole strain collection, revealing 102 sequence types (STs), of which 31 (30.4%) were novel. Eleven isolates (2.2%) belonged to the England(14)-9 clone, and 19 isolates (3.7%) belonged to, or were single-locus variants of, the Portugal(19F)-21 clone. The pneumococcal populations within the DCCs were composed of a majority of isolates with STs shared between the DCCs and a minority of isolates with STs unique for each DCC. The highest numbers of different STs, including novel STs, were found within the most frequent serotypes. Our study indicates that carriage of S. pneumoniae is highly prevalent among children in Norwegian DCCs, with a genetically diverse pneumococcal population consisting of unique microepidemic DCC populations.

Also flagged:depressionmajor depressionmild stressfluoxetinebehavioralgene expression
Journal Article 2008-06-04 No Snippets Surget A, Wang Y, Leman S, Ibarguen-Vargas Y, Edgar N, Griebel G, Belzung C, Sibille E.
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Gene microarrays may enable the elucidation of neurobiological changes underlying the pathophysiology and treatment of major depression. However, previous studies of antidepressant treatments were performed in healthy normal rather than 'depressed' animals. Since antidepressants are devoid of mood-changing effects in normal individuals, the clinically relevant rodent transcriptional changes could remain undetected. We investigated antidepressant-related transcriptome changes in a corticolimbic network of mood regulation in the context of the unpredictable chronic mild stress (UCMS), a naturalistic model of depression based on socio-environmental stressors. Mice subjected to a 7-week UCMS displayed a progressive coat state deterioration, reduced weight gain, and increased agonistic and emotion-related behaviors. Chronic administration of an effective (fluoxetine) or putative antidepressant (corticotropin-releasing factor-1 (CRF1) antagonist, SSR125543) reversed all physical and behavioral effects. Changes in gene expression differed among cingulate cortex (CC), amygdala (AMY) and dentate gyrus (DG) and were extensively reversed by both drugs in CC and AMY, and to a lesser extent in DG. Fluoxetine and SSR125543 also induced additional and very similar molecular profiles in UCMS-treated mice, but the effects of the same drug differed considerably between control and UCMS states. These studies established on a large-scale that the molecular impacts of antidepressants are region-specific and state-dependent, revealed common transcriptional changes downstream from different antidepressant treatments and supported CRF1 targeting as an effective therapeutic strategy. Correlations between UCMS, drug treatments, and gene expression suggest distinct AMY neuronal and oligodendrocyte molecular phenotypes as candidate systems for mood regulation and therapeutic interventions.

Also flagged:BDNFvesiclebrain-derived neurotrophic factorvesiclessecretioncytoplasmic
Journal Article 2008-06-04 ✓ 1 Snippet Park JJ, Cawley NX, Loh YP.
In-Text Gene Mentions

Htt

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Anterograde transport of brain-derived neurotrophic factor (BDNF) vesicles from the soma to neurite terminals is necessary for activity-dependent secretion of BDNF to mediate synaptic plasticity, memory and learning, and retrograde BDNF transport back to the soma for recycling. In our study, overexpression of the cytoplasmic tail of the carboxypeptidase E (CPE) found in BDNF vesicles significantly reduced localization of BDNF in neurites of hippocampal neurons. Live-cell imaging showed that the velocity and distance of movement of fluorescent protein-tagged CPE- or BDNF-containing vesicles were reduced in both directions. In pulldown assays, the CPE tail interacted with dynactin along with kinesin-2 and kinesin-3, and cytoplasmic dynein. Competition assays using a CPE tail peptide verified specific interaction between the CPE tail and dynactin. Thus, the CPE cytoplasmic tail binds dynactin that recruits kinesins or dynein for driving bi-directional transport of BDNF vesicle to maintain vesicle homeostasis and secretion in hippocampal neurons.

Also flagged:ironHepcidinpeptideCytokinesclodronatelipopolysaccharide
Journal Article 2008-06-03 ✓ 1 Snippet Theurl M, Theurl I, Hochegger K, Obrist P, Subramaniam N, van Rooijen N, Schuemann K, Weiss G.
In-Text Gene Mentions

…and in primary (Hfe-/-) and in…

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Hepcidin, a small cationic liver derived peptide, is a master regulator of body iron homeostasis. Cytokines and iron availability have so far been identified as regulators of hepcidin expression. Herein, we investigated the functional role of Kupffer cells for hepcidin expression because of their vicinity to the hepatocytes and their importance for iron recycling via erythrophagocytosis. We investigated C57Bl6 mice and littermates, in which Kupffer cells were eliminated in vivo upon intravenous injection of liposome-encapsulated clodronate. Primary cultures of hepatocytes and Kupffer cells were used to study direct regulatory effects ex vivo. The in vivo depletion of Kupffer cells resulted in a significant increase in liver hepcidin expression, which was paralleled by a significant reduction in serum iron levels. The same pattern of regulation by Kupffer cell depletion was observed upon injection of bacterial lipopolysaccharide into mice and in primary (Hfe -/-) and in secondary iron-overloaded mice. Accordingly, the messenger ribonucleic acid (mRNA) concentrations of the hepcidin iron-sensing molecule hemojuvelin were not significantly changed upon Kupffer cell depletion. When primary hepatocytes were cocultivated with Kupffer cells or stimulated with a Kupffer cell-conditioned medium ex vivo, a significant reduction in hepatocyte hepcidin mRNA expression was observed. Our data suggest that Kupffer cells control body iron homeostasis by exerting negative regulatory signals toward hepcidin expression, which may be primarily referred to the secretion of yet unidentified hepcidin-suppressing molecules by Kupffer cells.

Also flagged:embryonic stem cell differentiationlocalisationdouble-stranded RNA binding proteincell lineage differentiationgene expressionsynthesis
Journal Article 2008-06-03 No Snippets Gautrey H, McConnell J, Lako M, Hall J, Hesketh J.
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Pluripotent mouse embryonic stem (mES) cells derived from the blastocyst of the preimplantation embryo can be induced to differentiate in vitro along different cell lineages. However the molecular and cellular factors that signal and/or determine the expression of key genes, and the localisation of the encoded proteins, during the differentiation events are poorly understood. One common mechanism by which proteins can be targeted to specific regions of the cell is through the asymmetric localisation of mRNAs and Staufen, a double-stranded RNA binding protein, is known to play a direct role in mRNA transport and localisation. The aims of the present study were to describe the expression of Staufen in preimplantation embryos and mES cells and to use RNA interference (RNAi) to investigate the roles of Staufen1 in mES cell lineage differentiation. Western blotting and immunocytochemistry demonstrated that Staufen is present in the preimplantation mouse embryo, pluripotent mES cells and mES cells stimulated to differentiate into embryoid bodies, but the Staufen staining patterns did not support asymmetric distribution of the protein. Knockdown of Staufen1 gene expression in differentiating mES cells reduced the synthesis of lineage-specific markers including Brachyury, alpha-fetoprotein (AFP), PAX-6, and Vasa. There was however no significant change in either the gene expression of Nanog and Oct4, or in the synthesis of SSEA-1, all of which are key markers of pluripotency. These data indicate that inhibition of Staufen1 gene expression by RNAi affects an early step in mES cell differentiation and suggest a key role for Staufen in the cell lineage differentiation of mES cells.

Also flagged:chondrogenesisbeta1 integrinssox9collagen Xcollagen IIgene expressions
Journal Article 2008-06-02 ✓ 1 Snippet Lu ZF, Zandieh Doulabi B, Huang CL, Bank RA, Helder MN.
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…however, sox 9,sox6, and collagen II…

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Beta1 integrins play a controversial role during chondrogenesis. Since the maturation of chondrocytes relies on a signaling switch from cell-cell to cell-matrix interactions, we hypothesized that beta1 integrins play a different role at the earlier (mainly cell-cell interaction) from the later stage (mainly cell-matrix interaction) of chondrogenesis. Our data showed: in plain medium, sox9, collagen X, and collagen II gene expressions of ASCs were induced by beta1-integrin blockage at day 14. In chondrogenic medium, however, sox 9, sox6, and collagen II gene expression were induced at day 4 but inhibited at day 14. In addition, both beta1-integrin blockage and TGF-beta1 down-regulated Rock-1 and -2 gene expression and produced the round cells. We concluded that beta1 integrins play a more important role at the later stages than earlier stages of chondrogenesis, and that the onset of chondrogenesis promoted by beta1-integrin blockage might be through inhibiting Rock signaling.

Also flagged:SerinephosphorylationNRIF3ERp21-activated protein kinase 1Pak1
Journal Article 2008-06-02 ✓ 1 Snippet Talukder AH, Li DQ, Manavathi B, Kumar R.
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DCC

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NRIF3 is an estrogen-inducible nuclear receptor coregulator that stimulates estrogen receptor-alpha (ERalpha) transactivation functions and associates with the endogenous ER and its target gene promoter. p21-activated protein kinase 1 (Pak1) phosphorylates ERalpha at Ser305 and this modification is important in ERalpha transactivation function. Although ERalpha transactivation functions are regulated by co-activator activity of NRIF3, it remains unclear whether Pak1 could impact ER functions via a posttranslational modification of NRIF3. Here, we report that Pak1 phosphorylates NRIF3 at Serine28 and that NRIF3 binds to Pak1 in vitro and in vivo. We found that NRIF3 phosphorylation, co-activator activity and association with ERalpha increased following Pak1 phosphorylation of NRIF3's Ser28 and that activated ERalpha-Ser305 and NRIF3-Ser28 cooperatively support transactivation of ERalpha. NRIF3 expression increased significantly in cells with inducible Pak1 expression. We found that NRIF3 and ERalpha interaction, subcellular localization and ERalpha transactivation activity all increased in cells expressing the Pak1 phosphorylation-mimicking mutant NRIF3-Ser28Glu. Consistently, the NRIF3-Ser28Glu mutant exhibited an enhanced recruitment to the endogenous ER target genes and increased expression following estrogen stimulation. Finally, breast cancer cells with stable overexpression of NRIF3 showed increased proliferation and enhanced anchorage-independent growth. These findings suggest that NRIF3-Ser28 is a physiologic target of Pak1 signaling and contributes to the enhanced NRIF3 co-activator activity, leading to coordinated potentiation of ERalpha transactivation, its target gene expression and estrogen responsiveness of breast cancer cells.

Also flagged:Synthesismonoamine transporterdopamineserotoninnorepinephrine transportersbinding
Journal Article 2008-06-02 ✓ 3 Snippets Jin C, Navarro HA, Page K, Carroll FI.
In-Text Gene Mentions

…and serotonin transporter (5-HTT).…

…the NET and5-HTT, respectively, was the…

5-HTT

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A series of 2beta-[3'-(substituted benzyl)isoxazol-5-yl]- and 2beta-[3'-methyl-4'-(substituted phenyl)isoxazol-5-yl]-3beta-(substituted phenyl)tropanes were prepared and evaluated for affinities at dopamine, serotonin, and norepinephrine transporters using competitive radioligand binding assays. The 2beta-[3'-(substituted benzyl)isoxazol-5-yl]-3beta-(substituted phenyl)tropanes (3a-h) showed high binding affinities for the dopamine transporter (DAT). The IC(50) values ranged from 5.9 to 22nM. On the other hand, the 2beta-[3'-methyl-4'-(substituted phenyl)isoxazol-5-yl]-3beta-(substituted phenyl)tropanes (4a-h), with IC(50) values ranging from 65 to 173nM, were approximately 3- to 25-fold less potent than the corresponding 2beta-[3'-(substituted benzyl)isoxazol]tropanes. All tested compounds were selective for the DAT relative to the norepinephrine transporter (NET) and serotonin transporter (5-HTT). 3Beta-(4-Methylphenyl)-2beta-[3'-(4-fluorobenzyl)isoxazol-5-yl]tropane (3b) with IC(50) of 5.9nM at the DAT and K(i)s of 454 and 113nM at the NET and 5-HTT, respectively, was the most potent and DAT-selective analog. Molecular modeling studies suggested that the rigid conformation of the isoxazole side chain in 4a-h might play an important role on their low DAT binding affinities.

Also flagged:BisphosphonatebindingBisphosphonatescalciummineralbone resorption
Journal Article 2008-06-01 No Snippets Henneman ZJ, Nancollas GH, Ebetino FH, Russell RG, Phipps RJ.
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Bisphosphonates (BPs), which display a high affinity for calcium phosphate surfaces, are able to selectively target bone mineral, where they are potent inhibitors of osteoclast-mediated bone resorption. The dissolution of synthetic hydroxyapatite (HAP) has been used previously as a model for BP effects on natural bone mineral. The present work examines the influence of BPs on carbonated apatite (CAP), which mimics natural bone more closely than does HAP. Constant composition dissolution experiments were performed at pH 5.50, physiological ionic strength (0.15M) and temperature (37 degrees C). Selected BPs were added at (0.5 x 10(-6)) to (50.0 x 10(-6))M, and adsorption affinity constants, K(L), were calculated from the kinetics data. The BPs showed concentration-dependent inhibition of CAP dissolution, with significant differences in rank order zoledronate > alendronate > risedronate. In contrast, for HAP dissolution at pH 5.50, the differences between the individual BPs were considerably smaller. The extent of CAP dissolution was also dependent on the relative undersaturation, sigma, and CAP dissolution rates increased with increasing carbonate content. These results demonstrate the importance of the presence of carbonate in mediating the dissolution of CAP, and the possible involvement of bone mineral carbonate in observed differences in bone affinities of BPs in clinical use.

Also flagged:Huntingtin interacting proteinHYPKproteolysistrypsinamino acidsHuntington's disease
Journal Article 2008-06-01 ✓ 3 Snippets Raychaudhuri S, Majumder P, Sarkar S, Giri K, Mukhopadhyay D, Bhattacharyya NP.
In-Text Gene Mentions

Even though any link between the natively unfolded nature of HYPK, its conformational sensitivity towards Ca(2+) and interaction with Htt is yet to be established, its possible involvement in Huntington's disease pathogenesis is discussed.

…a novel huntingtin (Htt) interacting partner by…

…and interaction withHttis yet to…

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To characterize HYPK, originally identified as a novel huntingtin (Htt) interacting partner by yeast two hybrid assay, we used various biophysical and biochemical techniques. The molecular weight of the protein, determined by gel electrophoresis, was found to be about 1.3-folds ( approximately 22 kDa) higher than that obtained from mass spectrometric analysis (16.9 kDa). In size exclusion chromatography experiment, HYPK was eluted in three fractions, the hydrodynamic radii for which were calculated to be approximately 1.5-folds (23.06 A) higher than that expected for globular proteins of equivalent mass (17.3 A). The protein exhibited predominantly (63%) random coil characteristics in circular dichroism spectroscopy and was highly sensitive to limited proteolysis by trypsin and papain, indicating absence of any specific domain. Experimental evidences with theoretical analyses of amino acids composition of HYPK and comparison with available published data predicts that HYPK is an intrinsically unstructured protein (IUP) with premolten globule like conformation. In presence of increasing concentration of Ca(2+), HYPK showed conformational alterations as well as concomitant reduction of hydrodynamic radius. Even though any link between the natively unfolded nature of HYPK, its conformational sensitivity towards Ca(2+) and interaction with Htt is yet to be established, its possible involvement in Huntington's disease pathogenesis is discussed.

Also flagged:hypermethylationesophageal squamous cell carcinomaDeleted in Colorectal Cancertumor suppressor genecancersesophageal cancer
Journal Article 2008-06-01 ✓ 5 Snippets Park HL, Kim MS, Yamashita K, Westra W, Carvalho AL, Lee J, Jiang WW, Baek JH, Liu J, Osada M, Moon CS, Califano JA, Mori M, Sidransky D.
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We have demonstrated that DCC methylation is a frequent and cancer-specific event in primary ESCCs, suggesting that DCC and associated pathways may represent a new diagnostical therapeutic target.

DCC promoter hypermethylation in esophageal squamous cell carcinoma.

Decreased or loss of DCC expression has been demonstrated in a number of human cancers, including esophageal cancer.

DCC overexpression suppressed colony formation in ESCC cell lines, suggesting that DCC may function as a tumor suppressor gene in the esophagus.

In this study, we analyzed esophageal squamous cell carcinoma (ESCC) cell lines and primary ESCCs as well as normal esophageal tissues for DCC methylation by bisulfite sequencing, methylation-specific PCR (MSP) and/or quantitative methylation-specific PCR (qMSP).

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Deleted in Colorectal Cancer (DCC) is a putative tumor suppressor gene, whose loss has been implicated in colorectal tumorigenesis. Decreased or loss of DCC expression has been demonstrated in a number of human cancers, including esophageal cancer. In this study, we analyzed esophageal squamous cell carcinoma (ESCC) cell lines and primary ESCCs as well as normal esophageal tissues for DCC methylation by bisulfite sequencing, methylation-specific PCR (MSP) and/or quantitative methylation-specific PCR (qMSP). When a qMSP cut-off value for positivity was set to 1.0, DCC methylation was detected in 10 of 12 ESCC cell lines tested, 74% of primary ESCCs (n = 70), 0% of corresponding normal esophageal tissues (n = 20) and 0% of normal esophagus from healthy individuals (n = 19). DCC expression was undetectable in the majority of ESCC cell lines, and treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine reactivated gene expression. DCC overexpression suppressed colony formation in ESCC cell lines, suggesting that DCC may function as a tumor suppressor gene in the esophagus. However, DCC methylation was not associated with any clinical or pathologic parameters measured. We have demonstrated that DCC methylation is a frequent and cancer-specific event in primary ESCCs, suggesting that DCC and associated pathways may represent a new diagnostical therapeutic target.

Also flagged:ironsynthesisfrataxinpathogenesismetabolismtransferrin receptor
Journal Article 2008-06-01 ✓ 3 Snippets MacKenzie EL, Iwasaki K, Tsuji Y.
In-Text Gene Mentions

…the pathogenesis ofhemochromatosis, neurodegeneration, and infla…

HFE

hemochromatosis

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Maintenance of proper "labile iron" levels is a critical component in preserving homeostasis. Iron is a vital element that is a constituent of a number of important macromolecules, including those involved in energy production, respiration, DNA synthesis, and metabolism; however, excess "labile iron" is potentially detrimental to the cell or organism or both because of its propensity to participate in oxidation-reduction reactions that generate harmful free radicals. Because of this dual nature, elaborate systems tightly control the concentration of available iron. Perturbation of normal physiologic iron concentrations may be both a cause and a consequence of cellular damage and disease states. This review highlights the molecular mechanisms responsible for regulation of iron absorption, transport, and storage through the roles of key regulatory proteins, including ferroportin, hepcidin, ferritin, and frataxin. In addition, we present an overview of the relation between iron regulation and oxidative stress and we discuss the role of functional iron overload in the pathogenesis of hemochromatosis, neurodegeneration, and inflammation.

Also flagged:depressionmonoamine oxidase AMAOAserotonin transporterpsychiatric disorderorganization
Journal Article 2008-06-01 ✓ 1 Snippet Vanderbilt-Adriance E, Shaw DS.
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5-HTT

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This article examines potential theoretical constraints on resilience across levels of risk, time, and domain of outcome. Studies of resilience are reviewed as they relate to the prevalence of resilience across levels of risk (e.g., single life events vs. cumulative risk), time, and domains of adjustment. Based on a thorough review of pertinent literature, we conclude that resilience, as a global construct, appears to be rare at the highest levels of risk, and that resilience may benefit from a narrower conceptualization focusing on specific outcomes at specific timepoints in development. The implication of this conclusion for future research and intervention efforts is then discussed.

Also flagged:NetrinaxonsNetrin/deleted incolorectal cancerantibodieslaminin
Journal Article 2008-06-01 ✓ 4 Snippets Ratcliffe EM, D'Autréaux F, Gershon MD.
In-Text Gene Mentions

colorectal cancer (DCC

…Laminin terminates the Netrin/DCCmediated attraction of…

…in colorectal cancer (DCC) were found to…

DCC

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Vagal sensory axons navigate to specific sites in the bowel during fetal life. Netrin/deleted in colorectal cancer (DCC) were found to mediate the attraction of vagal sensory axons to the fetal mouse gut. We tested the hypothesis that laminin-111 can reverse the chemoattractive effects of netrin and act as a stop signal for vagal sensory axons. Laminin-111-expressing cells were located in the E12 and E16 mouse bowel by in situ hybridization. At E12, these cells extended centrifugally from the endoderm; by E16, laminin-111 expressing cells were found in the mucosa and outer gut mesenchyme. A similar pattern was seen in preparations of E13 and E15 mouse gut labeled with antibodies to laminin. Application of DiI to nodose ganglia identified vagal sensory axons growing into the fetal bowel. These terminals were found to avoid concentrations of laminin or to terminate at laminin-delimited boundaries. Soluble laminin inhibited the preferential growth of nodose neurites toward netrin-secreting cells (p < 0.01). This effect was mimicked by a peptide, YIGSR, a sequence within the beta1 chain of laminin-111 (p < 0.004) and antagonized by a peptide, IKVAV, a sequence within the alpha1 chain of laminin-111. Antibodies to beta1-integrins were also able to reverse the inhibitive effects of laminin and restore the attraction of nodose neurites towards netrin-1-secreting cells. Soluble laminin inhibited the preferential growth of nodose neurites toward a cocultured explant of foregut. These findings suggest that laminin terminates the attraction of vagal sensory axons towards sources of netrin in the developing bowel.

Also flagged:Hereditary hemochromatosisHHgenetic diseaseironcirrhosisdiabetes mellitus
Journal Article 2008-06-01 ✓ 2 Snippets Fowler C.
In-Text Gene Mentions

The C282Y mutation on the HFE gene accounts for most cases of HH; however, other genetic mutations have been identified.

…mutation on theHFEgene accounts for…

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Hereditary hemochromatosis (HH) is an autosomal recessive genetic disease resulting in inappropriate intestinal iron absorption leading to iron overload and end-organ disease. The disease is most prevalent in white individuals of European descent. The C282Y mutation on the HFE gene accounts for most cases of HH; however, other genetic mutations have been identified. End-organ damage results in cirrhosis, diabetes mellitus, and cardiomyopathy. Therapeutic phlebotomy to deplete excessive iron stores is the standard treatment of HH and results in normal longevity if therapy is initiated before end-organ disease occurs.

Also flagged:CASenvelopenucleoplasmimportin-αcellular apoptosis susceptibility protein
Journal Article 2008-06-01 No Snippets Kodiha M, Bański P, Ho-Wo-Cheong D, Stochaj U.
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The physiological state of eukaryotic cells controls nuclear trafficking of numerous cargos. For example, stress results in the inhibition of classical protein import, which is characterized by the redistribution of several transport factors. As such, importin-alpha and cellular apoptosis susceptibility protein (CAS) accumulate in nuclei of heat-shocked cells; however, the mechanisms underlying this relocation are not fully understood. We now show that heat upregulates the initial docking of importin-alpha at the nuclear envelope and stimulates the translocation of CAS into the nuclear interior. Moreover, heat exposure compromises the exit of importin-alpha from nuclei and drastically increases its retention in the nucleoplasm, whereas CAS nuclear exit and retention are less affected. Taken together, our results support the idea that heat shock regulates importin-alpha and CAS nuclear accumulation at several levels. The combination of different stress-induced changes leads to the nuclear concentration of both transport factors in heat-stressed cells.

Also flagged:chromosomesbone developmenttranscription factorsdinucleotideCol1a2CD38
Journal Article 2008-06-01 No Snippets Norgard EA, Roseman CC, Fawcett GL, Pavlicev M, Morgan CD, Pletscher LS, Wang B, Cheverud JM.
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<h4>Introduction</h4>Study of mutations with large phenotypic effects has allowed the identification of key players in skeletal development. However, the molecular nature of variation in large, phenotypically normal populations tends to be characterized by smaller phenotypic effects that remain undefined.<h4>Materials and methods</h4>We use interval mapping and quantitative trait locus (QTL) mapping techniques in the combined F2-F3 populations (n = 2111) of an LG/J x SM/J mouse intercross to detect QTLs associated with the lengths of the humerus, ulna, femur, and tibia.<h4>Results</h4>Seventy individual trait QTLs affecting long bone lengths were detected, with several chromosomes harboring multiple QTLs. The genetic architecture suggests mainly small, additive effects on long bone length, with roughly one third of the QTLs displaying dominance. Sex interactions were common, and four sex-specific QTLs were observed. Pleiotropy could not be rejected for most of the QTLs identified. Thirty-one epistatic interactions were detected, almost all affecting regions including or immediately adjacent to QTLs.<h4>Conclusions</h4>A complex regulatory network with many gene interactions modulates bone growth, possibly with integrated skeletal modules that allow fine-tuning of developmental processes present. Candidate genes in the QTL CIs include many genes known to affect endochondral bone growth and genes that have not yet been associated with bone growth or body size but have a strong potential to influence these traits.

Also flagged:Serotonin transportersertralinemajor depressionMDdrug-metabolizing transporterMD disorders
Journal Article 2008-06-01 ✓ 2 Snippets Dogan O, Yuksel N, Ergun MA, Yilmaz A, Ilhan MN, Karslioglu HE, Koc A, Menevse A.
In-Text Gene Mentions

…The serotonin transporter (5-HTT) gene is a…

…regions of the5-HTTgene (5-HTTLPR and…

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Major depression (MD) has a complex multifactorial etiology with genetic and environmental factors contributing to the disorder. As with all antidepressant treatments, there is variability in drug response due to heredity, generally focusing on genetic polymorphism of the drug-metabolizing transporter genes. The serotonin transporter (5-HTT) gene is a particularly important candidate for genetic involvement in MD disorders owing to its key role in the regulation of serotonergic transmission and is therefore considered to be an interesting candidate in the mechanism of antidepressant drugs. In this study, we have focused on the associations between genetic polymorphisms in two regions of the 5-HTT gene (5-HTTLPR and VNTR) related to sertraline responses. Our sample consisted of 64 unrelated Turkish subjects who strictly met DSM-IV and CGI scores. There was no significant difference between the frequency of the SS, LS, LL, 9/10, 10/10, 9/12, 10/12, and 12/12 genotypes and responses to sertraline. However, the number of patients can be increased and different drugs can be studied in order to find a specific pharmacogenetic relation.

Also flagged:HNSCCchromosomal regionsmethylationCDKN2Agene silencingDAPK1
Journal Article 2008-06-01 No Snippets Schmezer P, Plass C.
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For years, head and neck squamous cell carcinomas (HNSCC) have been among the leading cancers worldwide. Despite considerable efforts, the 5-year survival rate for HNSCC has not changed significantly. To improve this situation, it is necessary to understand the fundamental biological processes leading to the disease and its progression. In addition to known genetic changes in HNSCC, molecular cytogenetic investigations have identified chromosomal regions of gains and losses, but many of the responsible candidate genes have yet to be identified. Furthermore, recent results indicate the importance of epigenetic modifications in HNSCC, such as DNA methylation. Several genes, including the tumor suppressor CDKN2A and other candidates such as DAPK1, MGMT, TIMP3, TCF21, and C/EBPalpha, have been found to harbor hypermethylated regulatory sequences that lead to reduced expression or gene silencing. Hypermethylation in such genes could be used not only as biomarkers for the early detection of HNSCC but also to improve prevention strategies and therapy outcomes.

Also flagged:mineralmetabolismkidney diseaseCalciumPhosphorusMagnesium
Journal Article 2008-06-01 No Snippets Moe SM.
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Disorders of mineral metabolism are common in both the office and hospital setting. The diagnosis can be simplified by remembering the target organs involved--intestine, kidney, and bone--and by assessing the presence of kidney disease, levels of parathyroid hormone, and vitamin D status. Although the list of possible causes for these derangements is long, most patients who have hypercalcemia have hyperparathyroidism or malignancy; those who have hypocalcemia, hypophosphatemia, and hypomagnesemia have reduced gastrointestinal absorption, and those who have hyperphosphatemia and hypermagnesemia have increased intake in the setting of kidney disease.

Also flagged:HHironHLA
Journal Article 2008-06-01 ✓ 5 Snippets Mennella G, Valverde S, Forzan S, Fezzi M, Munaretto G, Gessoni G.
In-Text Gene Mentions

hemochromatosis gene (HFE

…High prevalence ofHFEgene mutations in…

…<h4>Aim</h4>Hemochromatosis(HH) was a…

…in the HLA-linkedhemochromatosisgene (HFE).…

…-linked hemochromatosis gene (HFE).…

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<h4>Aim</h4>Hemochromatosis (HH) was a common inherited disease characterized by iron overload. This disease is usually the result of mutations in the HLA-linked hemochromatosis gene (HFE). The aim of this study was to evaluate the frequency of HFE mutations in a group of Venetian hemodialysis patients.<h4>Methods</h4>Sixty-one hemodialysis patients, 62 patients with laboratory findings suggestive for iron overload, 57 repeat blood donors were enrolled in the study. HFE mutations were detected by using a commercial strip assay.<h4>Results</h4>In this study only H63D and C282Y mutations were observed. The overall prevalence of HFE mutations was 40.9% among hemodialysis patients, 30.6% among patients with laboratory findings of iron overload and 15.8% among blood donors.<h4>Conclusion</h4>A high prevalence of HFE mutation among hemodialysis patients was observed. Prevalence of HFE mutation in this group was 40.9%, significantly higher than results observed among blood donors (15.8%, P<0.005) or among patients with laboratory signs of iron overload (30.6%, P<0.01). These data are, at present inexplicable, and this results need further confirmation.

Also flagged:proteasomesignal transductiondegradationautophagyubiquitinneurological disorders
Journal Article 2008-06-01 No Snippets Chen JJ, Lin F, Qin ZH.
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There are two degradation systems in mammalian cells, autophagy/lysosomal pathway and ubiquitin-proteasome pathway. Proteasome is consist of multiple protein subunits and plays important roles in degradation of short-lived cellular proteins. Recent studies reveal that proteasomal degradation system is also involved in signal transduction and regulation of various cellular functions. Dysfunction or dysregulation of proteasomal function may thus be an important pathogenic mechanism in certain neurological disorders. This paper reviews the biological functions of proteasome in signal transduction and its potential roles in neurodegenerative diseases.

Also flagged:Galaningalanin receptordepressionmood disordersnoradrenalineserotonin
Journal Article 2008-06-01 No Snippets Kuteeva E, Hökfelt T, Wardi T, Ogren SO.
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The pathophysiology of depression remains unclear, but involves disturbances in brain monoaminergic transmission. Current antidepressant drugs, which act by enhancing this type of transmission, have limited therapeutic efficacy in a number of patients, and not rarely serious side-effects. Increasing evidence suggests that neuropeptides, including galanin, can be of relevance in mood disorders. Galanin is coexpressed with and modulates noradrenaline and serotonin systems, both implicated in depression. Pharmacological and genetic studies have suggested a role for galanin in depression-like behaviour in rodents, whereby the receptor subtype involved appears to play an important role. Thus, stimulation of GalR1 and/or GalR3 receptors results in depression-like phenotype, while activation of the GalR2 receptor attenuates depression-like behaviour. These findings suggest that galanin receptor subtypes represent targets for development of novel antidepressant drugs.

Also flagged:chronic diseaseRAstomach cancerchronic diseasesHLAinherited blood disorders
Journal Article 2008-06-01 ✓ 1 Snippet Bodmer W, Bonilla C.
In-Text Gene Mentions

hemochromatosis

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Here, we give a historical overview of the search for genetic variants that influence the susceptibility of an individual to a chronic disease, from RA Fisher's seminal work to the current excitement of whole-genome association studies (WGAS). We then discuss the concepts behind the identification of common variants as disease causal factors and contrast them to the basic ideas that underlie the rare variant hypothesis. The identification of rare variants involves the careful selection of candidate genes to examine, the availability of highly efficient resequencing techniques and the appropriate assessment of the functional consequences of the implicated variant. We believe that this strategy can be successfully applied at present in order to unravel the contribution of rare variants to the multifactorial inheritance of common diseases, which could lead to the implementation of much needed preventative screening schemes.

Also flagged:celiac diseaseOligonucleotideamyotrophic lateral sclerosisnucleotideceliachuman leukocyte antigen
Journal Article 2008-06-01 No Snippets Franke L, de Kovel CG, Aulchenko YS, Trynka G, Zhernakova A, Hunt KA, Blauw HM, van den Berg LH, Ophoff R, Deloukas P, van Heel DA, Wijmenga C.
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Copy-number variation (CNV) is a major contributor to human genetic variation. Recently, CNV associations with human disease have been reported. Many genome-wide association (GWA) studies in complex diseases have been performed with sets of biallelic single-nucleotide polymorphisms (SNPs), but the available CNV methods are still limited. We present a new method (TriTyper) that can infer genotypes in case-control data sets for deletion CNVs, or SNPs with an extra, untyped allele at a high-resolution single SNP level. By accounting for linkage disequilibrium (LD), as well as intensity data, calling accuracy is improved. Analysis of 3102 unrelated individuals with European descent, genotyped with Illumina Infinium BeadChips, resulted in the identification of 1880 SNPs with a common untyped allele, and these SNPs are in strong LD with neighboring biallelic SNPs. Simulations indicate our method has superior power to detect associations compared to biallelic SNPs that are in LD with these SNPs, yet without increasing type I errors, as shown in a GWA analysis in celiac disease. Genotypes for 1204 triallelic SNPs could be fully imputed, with only biallelic-genotype calls, permitting association analysis of these SNPs in many published data sets. We estimate that 682 of the 1655 unique loci reflect deletions; this is on average 99 deletions per individual, four times greater than those detected by other methods. Whereas the identified loci are strongly enriched for known deletions, 61% have not been reported before. Genes overlapping with these loci more often have paralogs (p = 0.006) and biologically interact with fewer genes than expected (p = 0.004).

Also flagged:tumorangiogenesiscell growthgene expressionbreast cancerCarcinoma
Journal Article 2008-06-01 No Snippets Mishra PJ, Mishra PJ, Humeniuk R, Medina DJ, Alexe G, Mesirov JP, Ganesan S, Glod JW, Banerjee D.
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Carcinoma-associated fibroblasts (CAF) have recently been implicated in important aspects of epithelial solid tumor biology, such as neoplastic progression, tumor growth, angiogenesis, and metastasis. However, neither the source of CAFs nor the differences between CAFs and fibroblasts from nonneoplastic tissue have been well defined. In this study, we show that human bone marrow-derived mesenchymal stem cells (hMSCs) exposed to tumor-conditioned medium (TCM) over a prolonged period of time assume a CAF-like myofibroblastic phenotype. More importantly, these cells exhibit functional properties of CAFs, including sustained expression of stromal-derived factor-1 (SDF-1) and the ability to promote tumor cell growth both in vitro and in an in vivo coimplantation model, and expression of myofibroblast markers, including alpha-smooth muscle actin and fibroblast surface protein. hMSCs induced to differentiate to a myofibroblast-like phenotype using 5-azacytidine do not promote tumor cell growth as efficiently as hMSCs cultured in TCM nor do they show increased SDF-1 expression. Furthermore, gene expression profiling revealed similarities between TCM-exposed hMSCs and CAFs. Taken together, these data suggest that hMSCs are a source of CAFs and can be used in the modeling of tumor-stroma interactions. To our knowledge, this is the first report showing that hMSCs become activated and resemble carcinoma-associated myofibroblasts on prolonged exposure to conditioned medium from MDAMB231 human breast cancer cells.

Also flagged:bupropion hydrochloridebupropioncell adhesionsubstance dependencenicotinepsychiatric disorder
Journal Article 2008-06-01 No Snippets Uhl GR, Liu QR, Drgon T, Johnson C, Walther D, Rose JE, David SP, Niaura R, Lerman C.
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<h4>Context</h4>Smoking remains a major public health problem. Twin studies indicate that the ability to quit smoking is substantially heritable, with genetics that overlap modestly with the genetics of vulnerability to dependence on addictive substances.<h4>Objectives</h4>To identify replicated genes that facilitate smokers' abilities to achieve and sustain abstinence from smoking (herein after referred to as quit-success genes) found in more than 2 genome-wide association (GWA) studies of successful vs unsuccessful abstainers, and, secondarily, to nominate genes for selective involvement in smoking cessation success with bupropion hydrochloride vs nicotine replacement therapy (NRT).<h4>Design</h4>The GWA results in subjects from 3 centers, with secondary analyses of NRT vs bupropion responders.<h4>Setting</h4>Outpatient smoking cessation trial participants from 3 centers.<h4>Participants</h4>European American smokers who successfully vs unsuccessfully abstain from smoking with biochemical confirmation in a smoking cessation trial using NRT, bupropion, or placebo (N = 550).<h4>Main outcome measures</h4>Quit-success genes, reproducibly identified by clustered nominally positive single-nucleotide polymorphisms (SNPs) in more than 2 independent samples with significant P values based on Monte Carlo simulation trials. The NRT-selective genes were nominated by clustered SNPs that display much larger t values for NRT vs placebo comparisons. The bupropion-selective genes were nominated by bupropion-selective results.<h4>Results</h4>Variants in quit-success genes are likely to alter cell adhesion, enzymatic, transcriptional, structural, and DNA, RNA, and/or protein-handling functions. Quit-success genes are identified by clustered nominally positive SNPs from more than 2 samples and are unlikely to represent chance observations (Monte Carlo P< .0003). These genes display modest overlap with genes identified in GWA studies of dependence on addictive substances and memory.<h4>Conclusions</h4>These results support polygenic genetics for success in abstaining from smoking, overlap with genetics of substance dependence and memory, and nominate gene variants for selective influences on therapeutic responses to bupropion vs NRT. Molecular genetics should help match the types and/or intensity of antismoking treatments with the smokers most likely to benefit from them.

Also flagged:calciummineralvascular calcificationhypertensionaortic stenosiscardiac hypertrophy
Journal Article 2008-06-01 No Snippets Demer LL, Tintut Y.
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No abstract available.

Also flagged:type 2 diabetestype 2 diabetes mellitusNucleotidepolymerasedeoxy-ribonucleic acidrestriction enzyme
Journal Article 2008-06-01 ✓ 5 Snippets Sharifi F, Esmaeilzadeh A, Zali M.
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To assess the frequency of 2 different forms of hemochromatosis HFE gene mutations (C282Y and H63D mutations) in a normal population in comparison with type 2 diabetic patients.

Based on our data, HFE mutations were not found in excess in patients with T2DM, and there was no evidence that a population-based search for an excess of these alleles in type 2 diabetes was indicated.

The distribution of genotypes was not statistically different.<h4>Conclusion</h4>Based on our data, HFE mutations were not found in excess in patients with T2DM, and there was no evidence that a population-based search for an excess of these alleles in type 2 diabetes was indicated.

Hemochromatosis gene (HFE) mutations in patients with type 2 diabetes and their control group in an Iranian population.

…Hemochromatosis gene (HFE) mutations in patients…

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<h4>Objective</h4>To assess the frequency of 2 different forms of hemochromatosis HFE gene mutations (C282Y and H63D mutations) in a normal population in comparison with type 2 diabetic patients.<h4>Methods</h4>This case control study was undertaken in Zanjan Diabetic Care Center, Zanjan, western Tehran, in 2005. Two hundred and two individuals were included in this study: 101 type 2 diabetes mellitus (T2DM) patients, and 101 age, and gender-matched controls. The patients were examined for mutations in the HFE gene. Nucleotide 845 (C282Y) and 187 (H63D) alleles were amplified by polymerase chain reaction PCR with lymphocyte deoxy-ribonucleic acid. The PCR products were analyzed by restriction enzyme digestion. Chi-square, student's t test, and Fisher's exact tests were used for comparison, and odds' ratio was calculated.<h4>Results</h4>Two hundred and two individuals were studied. The frequency of wild/C282Y alleles was 98/2% in T2DM patients, and 99/1% in controls p=0.6. The frequency of wild/H63D alleles was 68.3/31.7% in diabetics p=0.08, and 73.4/26.3% in control subjects p=0.08. The distribution of genotypes was not statistically different.<h4>Conclusion</h4>Based on our data, HFE mutations were not found in excess in patients with T2DM, and there was no evidence that a population-based search for an excess of these alleles in type 2 diabetes was indicated.

Also flagged:Zic2axonslocalizationgrowth conesEphB1 receptoraxon
Journal Article 2008-06-01 ✓ 1 Snippet Lee R, Petros TJ, Mason CA.
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DCC

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The navigation of retinal axons to ipsilateral and contralateral targets in the brain depends on the decision to cross or avoid the midline at the optic chiasm, a critical guidance maneuver that establishes the binocular visual pathway. Previous work has identified a specific guidance receptor, EphB1, that mediates the repulsion of uncrossed axons away from its ligand, ephrinB2, at the optic chiasm midline (Williams et al., 2003), and a transcription factor Zic2, that, like EphB1, is required for formation of the ipsilateral retinal projection (Herrera et al., 2003). Although the reported similarities in localization implicated that Zic2 regulates EphB1 (Herrera et al., 2003; Williams et al., 2003; Pak et al., 2004), whether Zic2 drives expression of EphB1 protein has not been elucidated. Here we show that EphB1 protein is expressed in the growth cones of axons from ventrotemporal (VT) retina that project ipsilaterally and that repulsion by ephrinB2 is determined by the presence of this receptor on growth cones. Moreover, ectopic delivery of Zic2 into explants from non-VT retina induces expression of EphB1 mRNA and protein. The upregulated EphB1 receptor protein is localized to growth cones and is functional, because it is sufficient to change retinal ganglion cell axon behavior from extension onto, to avoidance of, ephrinB2 substrates. Our results demonstrate that Zic2 upregulates EphB1 expression and define a link between a transcription factor and expression of a guidance receptor protein essential for axon guidance at the vertebrate midline.

Also flagged:quinolinessynthesisquinolinequindolinemethylcryptolepine
Journal Article 2008-06-01 No Snippets Kumar EV, Etukala JR, Ablordeppey SY.
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The tetracyclic indolo[3,2-b]quinoline ring system constitutes an important structural moiety in natural products exhibiting numerous biological activities. In particular, indolo [3, 2-b]quinoline, commonly known as linear quindoline is of particular interest, because of its rigid structure and scope of derivatization. Although the core linear quindoline skeleton shows little or no activity in several biological systems, introduction of a methyl group on the N-5 atom leading to cryptolepine induces remarkable activity against a broad spectrum of biological targets. A number of analogs of quindoline and cryptolepine have been synthesized, incorporating various functional groups on the core quindoline skeleton leading to improved biological activities. In this review, we describe various synthetic methodologies leading to the quindoline scaffold, the biological activities and the structure activity relationships (SAR) of quindoline derivatives toward different disease states to give a better picture of the importance of this moiety in medicinal chemistry.

Also flagged:Sryboxtranscription factorsSox5L-Sox5death
Journal Article 2008-06-01 ✓ 2 Snippets Dy P, Han Y, Lefebvre V.
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…of Sox5 fl+/fl+Sox6fl+/fl+ Prx1Cre mice…

Sox6

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Sox5 belongs to the Sry-related HMG box gene family, which encodes transcription factors controlling cell fate and differentiation in many lineages. Sox5 produces a long L-Sox5 protein in neuronal, glial, neural crest, cartilage, and other cells, and a short Sox5 protein in spermatids. Sox5(-/-) mice have revealed essential roles for L-Sox5 in development but their neonatal death has prevented postnatal studies. We show here that we have generated mice harboring a conditional null allele for L-Sox5 (Sox5(fl+)) by flanking the fifth coding exon with loxP sites. Cre recombinase-mediated conversion of Sox5(fl+) into Sox5(fl-) abolishes L-Sox5 expression. Expectedly, Sox5(fl+/fl+) mice are indistinguishable from wildtype mice, and Sox5(fl-/fl-) mice from Sox5(-/-) mice. Moreover, the chondrodysplasia of Sox5(fl+/fl+)Sox6(fl+/fl+)Prx1Cre mice demonstrates that the two redundant chondrogenic Sox genes can be efficiently inactivated in a cell type-specific manner. This Sox5 conditional null allele will be valuable in further uncovering the in vivo roles of L-Sox5.

Also flagged:mossy fiberNetrin-1Hoxa2Hoxb2chromatinRobo2
Journal Article 2008-06-01 ✓ 5 Snippets Geisen MJ, Di Meglio T, Pasqualetti M, Ducret S, Brunet JF, Chedotal A, Rijli FM.
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…controlled by the Netrin-1/Dccattractive pathway, little…

…in colon cancer (Dcc)/Netrin-1–mediated chemoattra…

…Systems), goat anti-humanDCC(Santa Cruz Biotechnology),…

…involves the Netrin-1 ligand/Dccreceptor guidance system…

…whereas its receptorDccis expressed in…

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The pontine neurons (PN) represent a major source of mossy fiber projections to the cerebellum. During mouse hindbrain development, PN migrate tangentially and sequentially along both the anteroposterior (AP) and dorsoventral (DV) axes. Unlike DV migration, which is controlled by the Netrin-1/Dcc attractive pathway, little is known about the molecular mechanisms guiding PN migration along the AP axis. Here, we show that Hoxa2 and Hoxb2 are required both intrinsically and extrinsically to maintain normal AP migration of subsets of PN, by preventing their premature ventral attraction towards the midline. Moreover, the migration defects observed in Hoxa2 and Hoxb2 mutant mice were phenocopied in compound Robo1;Robo2, Slit1;Slit2, and Robo2;Slit2 knockout animals, indicating that these guidance molecules act downstream of Hox genes to control PN migration. Indeed, using chromatin immunoprecipitation assays, we further demonstrated that Robo2 is a direct target of Hoxa2 in vivo and that maintenance of high Robo and Slit expression levels was impaired in Hoxa2 mutant mice. Lastly, the analysis of Phox2b-deficient mice indicated that the facial motor nucleus is a major Slit signaling source required to prevent premature ventral migration of PN. These findings provide novel insights into the molecular control of neuronal migration from transcription factor to regulation of guidance receptor and ligand expression. Specifically, they address the question of how exposure to multiple guidance cues along the AP and DV axes is regulated at the transcriptional level and in turn translated into stereotyped migratory responses during tangential migration of neurons in the developing mammalian brain.

Also flagged:cholesterolbindingmembrane proteinmembranetimololsterol
Journal Article 2008-06-01 No Snippets Hanson MA, Cherezov V, Griffith MT, Roth CB, Jaakola VP, Chien EY, Velasquez J, Kuhn P, Stevens RC.
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The role of cholesterol in eukaryotic membrane protein function has been attributed primarily to an influence on membrane fluidity and curvature. We present the 2.8 A resolution crystal structure of a thermally stabilized human beta(2)-adrenergic receptor bound to cholesterol and the partial inverse agonist timolol. The receptors pack as monomers in an antiparallel association with two distinct cholesterol molecules bound per receptor, but not in the packing interface, thereby indicating a structurally relevant cholesterol-binding site between helices I, II, III, and IV. Thermal stability analysis using isothermal denaturation confirms that a cholesterol analog significantly enhances the stability of the receptor. A consensus motif is defined that predicts cholesterol binding for 44% of human class A receptors, suggesting that specific sterol binding is important to the structure and stability of other G protein-coupled receptors, and that this site may provide a target for therapeutic discovery.

Also flagged:ironmetabolismrestless legs syndromeiron insufficiencytransferrin receptorTfR
Journal Article 2008-06-01 ✓ 1 Snippet Earley CJ, Ponnuru P, Wang X, Patton SM, Conner JR, Beard JL, Taub DD, Allen RP.
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hemochromatosis

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<h4>Objective</h4>Studies using cerebrospinal fluid, magnetic resonance imaging, and autopsy tissue have implicated a primary role for brain iron insufficiency in restless legs syndrome (RLS). If the abnormalities of brain iron regulation reflect a basic disturbance of iron metabolism, then this might be expressed at least partially in some peripheral systems. Thus the study aim was to determine whether patients with RLS and control subjects show differences in lymphocyte iron regulator proteins.<h4>Methods</h4>Fasting morning blood samples were used to obtain common serum measures of iron status and to determine lymphocyte iron management proteins. Twenty-four women with early-onset RLS and 25 control women without RLS symptoms were studied.<h4>Results</h4>RLS and control subjects were matched for age, hemoglobin, and serum iron profile. However, transferrin receptor (TfR) and DMT1 (divalent metal transporter 1 protein) levels in lymphocytes were significantly higher for RLS patients than for controls. No significant differences in ferritin subtypes or transferrin levels were found. No significant correlations were found between lymphocyte and serum indices of iron status.<h4>Interpretation</h4>RLS lymphocytes showed an increase in ferroportin, implying increased cellular iron excretion, in the face of increased iron need (increased TfR and DMT1). In the absence of changes in H-ferritin, the findings indicate a balance between input and output with no net iron change but probable overall increase in iron turnover. The lack of any significant correlation between serum and lymphocyte iron indices indicates that iron management proteins from lymphocytes are at a minimum an alternative and independent marker of cellular iron metabolism.

Also flagged:liver fibrosistransaminaseliver diseaseASTALTiron
Journal Article 2008-06-01 ✓ 4 Snippets Beaton M, Adams PC.
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…liver fibrosis inhemochromatosisC282Y homozygotes with…

…screening studies forhemochromatosishave demonstrated an…

…liver fibrosis inhemochromatosismight be silent.…

…liver dysfunction inhemochromatosismight have underestimated…

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<h4>Background & aims</h4>Population screening studies for hemochromatosis have demonstrated an increase in liver disease in C282Y homozygotes, but many participants have no evidence of liver dysfunction. Previous studies have suggested that liver fibrosis in hemochromatosis might be silent. The objective of this study was to assess the degree of liver injury in referred C282Y homozygotes who underwent elective liver biopsy and had serum AST and ALT levels < 40 IU/L.<h4>Methods</h4>All C282Y homozygotes who underwent liver biopsy with normal AST and ALT levels were included in this study.<h4>Results</h4>There were 35 men and 16 women in the study with a mean age of 51 years (range, 16-89). The mean serum ferritin level was 637 microg/L (range, 18-2062), and mean liver iron concentration was 131 micromol/g (range, 11-386). There were 42 patients with no fibrosis, 6 patients with fibrosis, and 3 patients with cirrhosis.<h4>Conclusions</h4>Silent liver fibrosis with normal transaminase levels is seen in 18% of referred C282Y homozygotes. Studies that have reported on biochemical liver dysfunction in hemochromatosis might have underestimated the prevalence of liver injury from iron overload.

Also flagged:Huntington's diseaseHDchromosomeglutaminebehavioralfl
Journal Article 2008-06-01 ✓ 3 Snippets Gray M, Shirasaki DI, Cepeda C, André VM, Wilburn B, Lu XH, Tao J, Yamazaki I, Li SH, Sun YE, Li XJ, Levine MS, Yang XW.
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To elucidate the pathogenic mechanisms in Huntington's disease (HD) elicited by expression of full-length human mutant huntingtin (fl-mhtt), a bacterial artificial chromosome (BAC)-mediated transgenic mouse model (BACHD) was developed expressing fl-mhtt with 97 glutamine repeats under the control of endogenous htt regulatory machinery on the BAC.

…control of endogenoushttregulatory machinery on…

htt

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To elucidate the pathogenic mechanisms in Huntington's disease (HD) elicited by expression of full-length human mutant huntingtin (fl-mhtt), a bacterial artificial chromosome (BAC)-mediated transgenic mouse model (BACHD) was developed expressing fl-mhtt with 97 glutamine repeats under the control of endogenous htt regulatory machinery on the BAC. BACHD mice exhibit progressive motor deficits, neuronal synaptic dysfunction, and late-onset selective neuropathology, which includes significant cortical and striatal atrophy and striatal dark neuron degeneration. Power analyses reveal the robustness of the behavioral and neuropathological phenotypes, suggesting BACHD as a suitable fl-mhtt mouse model for preclinical studies. Additional analyses of BACHD mice provide novel insights into how mhtt may elicit neuropathogenesis. First, unlike previous fl-mhtt mouse models, BACHD mice reveal that the slowly progressive and selective pathogenic process in HD mouse brains can occur without early and diffuse nuclear accumulation of aggregated mhtt (i.e., as detected by immunostaining with the EM48 antibody). Instead, a relatively steady-state level of predominantly full-length mhtt and a small amount of mhtt N-terminal fragments are sufficient to elicit the disease process. Second, the polyglutamine repeat within fl-mhtt in BACHD mice is encoded by a mixed CAA-CAG repeat, which is stable in both the germline and somatic tissues including the cortex and striatum at the onset of neuropathology. Therefore, our results suggest that somatic repeat instability does not play a necessary role in selective neuropathogenesis in BACHD mice. In summary, the BACHD model constitutes a novel and robust in vivo paradigm for the investigation of HD pathogenesis and treatment.

Also flagged:OX40CD154FOXP3costimulation
Journal Article 2008-06-01 No Snippets Chen M, Xiao X, Demirci G, Li XC.
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The role of OX40 in the islet allograft tolerance, especially in the absence of CD154 costimulation, remains poorly defined. In the present study, we used CD154 deficient mice to critically examine the role of OX40 in the activation of T effector cells and Foxp3+ Tregs and the effect of blocking OX40 on the induction of islet allograft tolerance. We found that blocking OX40 costimulation in CD154 deficient mice induced donor specific tolerance but stimulating OX40 resulted in prompt islet allograft rejection. We also found that OX40 differentially regulates T effector cells and Foxp3+ Tregs, OX40 signaling mediates proliferation of CD154 deficient T effector cells but blocks the induction and suppressor functions of Foxp3+ Tregs. Our data suggest that the role of OX40 in the induction of islet allograft tolerance involves modifying not only the T effector cells but also the Foxp3+ Tregs in CD154 deficient mice.

The TNF Superfamily-2008.

Also flagged:TNFCytokinescytokineTRAILcancerLymphotoxin-β
Journal Article 2008-06-01 No Snippets Ware CF.
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No abstract available.

Also flagged:androgendimethandrolonenorandrogenandrogenstestosteroneestrogens
Journal Article 2008-06-01 No Snippets Attardi BJ, Pham TC, Radler LC, Burgenson J, Hild SA, Reel JR.
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Dimethandrolone undecanoate (DMAU: 7alpha,11beta-dimethyl-19-nortestosterone 17beta-undecanoate) is a potent orally active androgen in development for hormonal therapy in men. Cleavage of the 17beta-ester bond by esterases in vivo leads to liberation of the biologically active androgen, dimethandrolone (DMA), a 19-norandrogen. For hormone replacement in men, administration of C19 androgens such as testosterone (T) may lead to elevations in circulating levels of estrogens due to aromatization. As several reports have suggested that certain 19-norandrogens may serve as substrates for the aromatase enzyme and are converted to the corresponding aromatic A-ring products, it was important to investigate whether DMA, the related compound, 11beta-methyl-19-nortestosterone (11beta-MNT), also being tested for hormonal therapy in men, and other 19-norandrogens can be converted to aromatic A-ring products by human aromatase. The hypothetical aromatic A-ring product corresponding to each substrate was obtained by chemical synthesis. These estrogens bound with high affinity to purified recombinant human estrogen receptors (ER) alpha and beta in competitive binding assays (IC50's: 5-12 x 10(-9) M) and stimulated transcription of 3XERE-luciferase in T47Dco human breast cancer cells with a potency equal to or greater than that of estradiol (E2) (EC50's: 10(-12) to 10(-11) M). C19 androgens (T, 17alpha-methyltestosterone (17alpha-MT), androstenedione (AD), and 16alpha-hydroxyandrostenedione (16alpha-OHAD)), 19-norandrogens (DMA, 11beta-MNT, 19-nortestosterone (19-NT), and 7alpha-methyl-19-nortestosterone (MENT)) or the structurally similar 19-norprogestin, norethindrone (NET) were incubated at 50 microM with recombinant human aromatase for 10-180 min at 37 degrees C. The reactions were terminated by extraction with acetonitrile and centrifugation, and substrate and potential product were separated by HPLC. Retention times were monitored by UV absorption, and UV peaks were quantified using standard curves. Aromatization of the positive controls, T, AD, and 16alpha-OHAD was linear for 40-60 min, and conversion of T or AD was complete by 120 min. The nonsteroidal aromatase inhibitor, letrozole, demonstrated concentration-dependent suppression of T aromatization. Under the same conditions, there was no detectable conversion of DMA, 11beta-MNT, or NET to their respective hypothetical aromatic A-ring products during incubation times up to 180 min. Aromatization of MENT and 19-NT proceeded slowly and was limited. Collectively, these data support the notion that in the absence of the C19-methyl group, which is the site of attack by oxygen, aromatization of androgenic substrates proceeds slowly or not at all and that this reaction is impeded by the presence of a methyl group at the 11beta position.

Also flagged:mineralvitamin D receptorAPOEcalciumagingapolipoprotein E
Journal Article 2008-06-01 No Snippets Theppeang K, Glass TA, Bandeen-Roche K, Todd AC, Rohde CA, Links JM, Schwartz BS.
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<h4>Objective</h4>The objective of this study was to evaluate the relations between bone mineral density (BMD) and lead in blood, tibia, and patella and to investigate how BMD modifies these lead biomarkers in older women.<h4>Design</h4>In this study, we used cross-sectional analysis.<h4>Participants</h4>We studied 112 women, 50-70 years of age, including both whites and African Americans, residing in Baltimore, Maryland.<h4>Measurements</h4>We measured lumbar spine BMD, blood and bone lead by dual energy X-ray absorptiometry, anodic stripping voltammetry, and (109)Cd-induced K-shell X-ray fluorescence, respectively. We measured vitamin D receptor and apolipoprotein E (APOE) genotypes using standard methods.<h4>Results</h4>Mean (+/- SD) BMD and lead levels in blood, tibia, and patella were 1.02+/-0.16 g/cm(2), 3.3+/-2.2 microg/dL, 19.7+/-13.2 microg/g, and 5.7+/-15.3 microg/g, respectively. In adjusted analysis, higher BMD was associated with higher tibia lead levels (p=0.03). BMD was not associated with lead levels in blood or patella. There was evidence of significant effect modification by BMD on relations of physical activity with blood lead levels and by APOE genotype on relations of BMD with tibia lead levels. There was no evidence that BMD modified relations between tibia lead or patella lead and blood lead levels.<h4>Conclusions</h4>We believe that BMD represents the capacity of bone that can store lead, by substitution for calcium, and thus the findings may have relevance for effect-size estimates in persons with higher BMD.<h4>Relevance to clinical practice</h4>The results have implications for changes in lead kinetics with aging, and thus the related risk of health effects associated with substantial early- and midlife lead exposure in older persons.

Also flagged:nucleusnetrin-1axon guidancecell migrationaxonsRobo3 receptor
Journal Article 2008-06-01 ✓ 1 Snippet Di Meglio T, Nguyen-Ba-Charvet KT, Tessier-Lavigne M, Sotelo C, Chédotal A.
In-Text Gene Mentions

DCC

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Precerebellar neurons of the inferior olive (IO) and lateral reticular nucleus (LRN) migrate tangentially from the rhombic lip toward the floor plate following parallel pathways. This process is thought to involve netrin-1 attraction. However, whereas the cell bodies of LRN neurons cross the midline, IO neurons are unable to do so. In many systems and species, axon guidance and cell migration at the midline are controlled by Slits and their receptor Robos. We showed previously that precerebellar axons and neurons do not cross the midline in the absence of the Robo3 receptor. To determine whether this signaling by Slits and the two other Robo receptors, Robo1 and Robo2, also regulates precerebellar neuron behavior at the floor plate, we studied the phenotype of Slit1/2 and Robo1/2/3 compound mutants. Our results showed that many IO neurons can cross the midline in absence of Slit1/2 or Robo1/2, supporting a role for midline repellents in guiding precerebellar neurons. We also show that these molecules control the development of the lamellation of the inferior olivary complex. Last, the analysis of Robo1/2/3 triple mutants suggests that Robo3 inhibits Robo1/2 repulsion in precrossing LRN axons but not in IO axons in which it has a dominant and distinct function.

Also flagged:raf kinaseepithelial ovarian cancermetastasismalignant tumorRaf kinase inhibitorRKIP
Journal Article 2008-06-01 No Snippets Li HZ, Wang Y, Gao Y, Shao J, Zhao XL, Deng WM, Liu YX, Yang J, Yao Z.
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Loss of function of metastasis suppressor genes is an important step in the progression to a malignant tumor type. Studies in cell culture and animal models have suggested a role of Raf kinase inhibitor protein (RKIP) in suppressing the metastatic spread of prostate cancer, breast cancer, and melanoma cells. However, the function of RKIP in ovarian cancer (OVCA) has not been reported. To explore the potential role of RKIP in epithelial OVCA metastasis, we detected the expression levels of RKIP protein in tissue samples from patients with epithelial OVCA. Consequently, the expression of RKIP is reduced in the poorly differentiated OVCA than in the well-differentiated and moderately differentiated OVCA. In addition, in vitro cell invasion assay indicated that the RKIP expression was inversely associated with the invasiveness of five OVCA cell lines. Consistent with this result, the cell proliferation, anchorage-independent growth, cell adhesion, and invasion were decreased in RKIP overexpressed cells but increased in RKIP down-regulated cells. Further investigation indicated that RKIP inhibited OVCA cell proliferation by altering cell cycle progression rather than promoting apoptosis. Furthermore, the overexpression of RKIP suppressed the ability of human OVCA cells to metastasize when the tumor cells were transplanted into nude mice. Our data show the effect of RKIP on the proliferation, migration, or adhesion of OVCA cells. These results indicate that RKIP is also a metastasis suppressor gene of human epithelial OVCA.

Also flagged:estradiolclottingprostate cancerestrogencardiovascular diseaseandrogen
Journal Article 2008-06-01 ✓ 1 Snippet Taxel P, Luthra P, Fall PM, Dauser D.
In-Text Gene Mentions

…-inhibitor-1 (PAI-1) and anti-thrombin-III(AT-III) in 27…

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The cardio protective effect of estrogen in women has come under scrutiny as recent evidence from long-term trials has demonstrated negative findings. In contrast, the effect of endogenous sex hormones, specifically estrogen, on cardiovascular disease, inflammation and clotting parameters in men has not been well-studied. Men receiving androgen deprivation therapy for prostate cancer provide a unique model to study the effect of estrogen alone on inflammation and clotting factors. In a short-term randomized controlled trial of 17-beta estradiol (E(2)) versus placebo, we measured sex hormones, markers of inflammation including homocysteine (HC), C-reactive protein (CRP), interleukin-6 (IL-6) and coagulation factors including fibrinogen, plasminogen activator-inhibitor-1 (PAI-1) and anti-thrombin-III (AT-III) in 27 older men without bone metastases receiving androgen deprivation therapy or neoadjuvant treatment for prostate cancer. After 9 weeks of E(2) treatment, there was no difference in inflammation or clotting parameters between groups, but after 9 weeks of treatment AT-III increased in the E(2) treated group and decreased in the placebo group. CRP, homocysteine and IL-6 did not show any significant differences. We also evaluated the above parameters in 12 men 3 weeks after acute steroid withdrawal with androgen deprivation therapy and found no significant changes. We found an increase in AT-III in men receiving E(2) which may be related to gonadal steroid withdrawal, but no significant differences in other inflammatory or clotting factor parameters. While the current report is very preliminary in a small group of subjects, further studies are needed to determine the long-term effects of E(2) in this population of hypogonadal men.

Also flagged:Rad51chromatinbiotinhRad51presynaptic filamentsnucleosome
Journal Article 2008-06-01 ✓ 1 Snippet Sinha M, Peterson CL.
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linker histones

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Repair of chromosomal DNA double-strand breaks by homologous recombination is essential for cell survival and genome stability. Within eukaryotic cells, this repair pathway requires a search for a homologous donor sequence and a subsequent strand invasion event on chromatin fibers. We employ a biotin-streptavidin minichromosome capture assay to show that yRad51 or hRad51 presynaptic filaments are sufficient to locate a homologous sequence and form initial joints, even on the surface of a nucleosome. Furthermore, we present evidence that the Rad54 chromatin-remodeling enzyme functions to convert these initial metastable products of the homology search to a stable joint molecule that is competent for subsequent steps of the repair process. Thus, contrary to popular belief, nucleosomes do not pose a potent barrier for successful recognition and capture of homology by an invading presynaptic filament.

Also flagged:autismcancerimmune responsecomplexIGKCIg kappa chain
Journal Article 2008-06-01 ✓ 1 Snippet Blekhman R, Man O, Herrmann L, Boyko AR, Indap A, Kosiol C, Bustamante CD, Teshima KM, Przeworski M.
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HFE

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What evolutionary forces shape genes that contribute to the risk of human disease? Do similar selective pressures act on alleles that underlie simple versus complex disorders [1-3]? Answers to these questions will shed light onto the origin of human disorders (e.g., [4]) and help to predict the population frequencies of alleles that contribute to disease risk, with important implications for the efficient design of mapping studies [5-7]. As a first step toward addressing these questions, we created a hand-curated version of the Mendelian Inheritance in Man database (OMIM). We then examined selective pressures on Mendelian-disease genes, genes that contribute to complex-disease risk, and genes known to be essential in mouse by analyzing patterns of human polymorphism and of divergence between human and rhesus macaque. We found that Mendelian-disease genes appear to be under widespread purifying selection, especially when the disease mutations are dominant (rather than recessive). In contrast, the class of genes that influence complex-disease risk shows little signs of evolutionary conservation, possibly because this category includes targets of both purifying and positive selection.

Also flagged:DSCAMnetrin receptornetrin-1axonsaxon guidanceDown Syndrome Cell Adhesion Molecule
Journal Article 2008-06-01 ✓ 5 Snippets Ly A, Nikolaev A, Suresh G, Zheng Y, Tessier-Lavigne M, Stein E.
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…that collaborates withDCCin mediating turning…

…DSCAM andDCCcan each mediate…

…netrin-1 independently ofDCC.…

…by activating thenetrin receptor DCCreceptor DCC, but…

DCC

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During nervous system development, spinal commissural axons project toward and across the ventral midline. They are guided in part by netrin-1, made by midline cells, which attracts the axons by activating the netrin receptor DCC. However, previous studies suggest that additional receptor components are required. Here, we report that the Down's syndrome Cell Adhesion Molecule (DSCAM), a candidate gene implicated in the mental retardation phenotype of Down's syndrome, is expressed on spinal commissural axons, binds netrin-1, and is necessary for commissural axons to grow toward and across the midline. DSCAM and DCC can each mediate a turning response of these neurons to netrin-1. Similarly, Xenopus spinal neurons exogenously expressing DSCAM can be attracted by netrin-1 independently of DCC. These results show that DSCAM is a receptor that can mediate turning responses to netrin-1 and support a key role for netrin/DSCAM signaling in commissural axon guidance in vertebrates.

Also flagged:periodontitisperiodontal diseaseserotonin transporterbehavioralconditionsdepression
Journal Article 2008-06-01 No Snippets Costa JE, Gomes CC, Cota LO, Pataro AL, Silva JF, Gomez RS, Costa FO.
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Susceptibility to and development of periodontal disease have been associated with psychological conditions. Previous studies have associated the presence of polymorphism in the promoter region of the serotonin transporter with several behavioral traits and psychological conditions such as depression, anxiety, and stress. The short allele S has a reduced transcriptional efficiency and is associated with lowered serotonin expression and uptake. The purpose of the present study was to investigate the association between 5-HTTLPR polymorphism and aggressive periodontitis in a sample of Brazilian individuals. This study involved 61 individuals affected by aggressive periodontitis and 71 without periodontitis. Genomic DNA was obtained from oral swabs, amplified by polymerase chain reaction (PCR), and genotyped at 5-HTTLPR. The Chi-square test and multivariate logistic regression were used for statistical analysis. The aggressive periodontitis group displayed a significantly higher occurrence of genotype SS (P < 0.01) and of allele S (P < 0.01). After adjustment for gender and age, it was observed that genotype SS occurred 8 times more frequently in this group. Our findings suggest that 5-HTTLPR polymorphism might be associated with aggressive periodontitis in the Brazilian population.

Also flagged:Huntington's diseaseHDcytosineadenineguanineHuntingtin
Journal Article 2008-06-01 ✓ 1 Snippet Gil JM, Rego AC.
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Huntington's disease (HD) is caused by an expansion of cytosine-adenine-guanine (CAG) repeats in the huntingtin gene, which leads to neuronal loss in the striatum and cortex and to the appearance of neuronal intranuclear inclusions of mutant huntingtin.

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Huntington's disease (HD) is caused by an expansion of cytosine-adenine-guanine (CAG) repeats in the huntingtin gene, which leads to neuronal loss in the striatum and cortex and to the appearance of neuronal intranuclear inclusions of mutant huntingtin. Huntingtin plays a role in protein trafficking, vesicle transport, postsynaptic signaling, transcriptional regulation, and apoptosis. Thus, a loss of function of the normal protein and a toxic gain of function of the mutant huntingtin contribute to the disruption of multiple intracellular pathways. Furthermore, excitotoxicity, dopamine toxicity, metabolic impairment, mitochondrial dysfunction, oxidative stress, apoptosis, and autophagy have been implicated in the progressive degeneration observed in HD. Nevertheless, despite the efforts of a multidisciplinary scientific community, there is no cure for this devastating neurodegenerative disorder. This review presents an overview of the mechanisms that may contribute for HD pathogenesis. Ultimately, a better understanding of these mechanisms will lead to the development of more effective therapeutic targets.

Also flagged:triclosantriclocarbanbiocidecarbanilideDechlorinationmetals
Journal Article 2008-06-01 ✓ 1 Snippet Miller TR, Heidler J, Chillrud SN, DeLaquil A, Ritchie JC, Mihalic JN, Bopp R, Halden RU.
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DCC

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The biocides triclosan and triclocarban are wastewater contaminants whose occurrence and fate in estuarine sediments remain unexplored. We examined contaminant profiles in 137Cs/7Be-dated sediment cores taken near wastewater treatment plants in the Chesapeake Bay watershed (CB), Maryland and Jamaica Bay(JB), New York. In JB, biocide occurrences tracked the time course of biocide usage and wastewater treatment strategies employed, first appearing in the 1950s (triclocarban) and 1960s (triclosan), and peaking in the late 1960s and 1970s (24 +/- 0.54 and 0.8 +/- 0.4 mg/kg dry weight, respectively). In CB, where the time of sediment accumulation was not as well constrained by 137Cs depth profiles, triclocarban was only measurable in 137Cs-bearing sediments, peaking at 3.6 +/- 0.6 mg/ kg midway through the core and exceeding 1 mg/kg in recent deposits. In contrast, triclosan concentrations were low or not detectable in the CB core. Analysis of CB sediment by tandem mass spectrometry produced the first evidence for complete sequential dechlorination of triclocarban to the transformation products dichloro-, monochloro-, and unsubstituted carbanilide, which were detected at maxima of 15.5 +/- 1.8, 4.1 +/- 2.4, and 0.5 +/- 0.1 mg/kg, respectively. Concentrations of all carbanilide congeners combined were correlated with heavy metals (R2 > 0.64, P < 0.01), thereby identifying wastewater as the principal pathway of contamination. Environmental persistence over the past 40 years was observed for triclosan and triclocarban in JB, and for triclocarban's diphenylurea backbone in CB sediments.

Also flagged:Vascular endothelial growth factorperitonitissynthesisVEGFlipopolysaccharideglucose
Journal Article 2008-06-01 ✓ 2 Snippets Pawlaczyk K, Polubinska A, Numata N, Nakayama M, Pecoits-Filho R, Czekalski S, Lindholm B, Breborowicz A.
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…0.005 ) . DCC ( cells/microL )…

…reaction with increasedDCCand cytokine levels,…

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<h4>Background</h4>Peritoneal inflammation may induce changes in peritoneal microvessels, including neoangiogenesis/vasculogenesis, leading to increased peritoneal solute transport rate (PSTR) and loss of ultrafiltration capacity. We hypothesized that an inflammatory reaction in the peritoneal cavity during peritonitis induces increased synthesis of vascular endothelial growth factor (VEGF). We therefore studied the relationship between peritoneal inflammation markers, VEGF, and transport of fluid and solutes in rats during acute peritoneal inflammation induced by lipopolysaccharide (LPS) added to standard glucose-based dialysis solution.<h4>Methods</h4>Under ether anesthesia, male Wistar rats were injected intraperitoneally with 30 mL Dianeal 3.86% without (Control; n=6) or with LPS (microg/mL): 0.001 (LPS 0.001; n=6), 0.01 (LPS 0.01; n=7), 0.1 (LPS 0.1; n=7), 1.0 (LPS 1.0; n=8). After 8 hours, dialysate volume (IPV), peritoneal solute transport rate (PSTR) and dialysate cell count (DCC) were measured and effluent samples were collected.<h4>Results</h4>LPS i.p. resulted in increased PSTR and decreased IPV (p<0.005). DCC (cells/microL) and the neutrophil/macrophage ratio were higher for all LPS concentrations compared to the control group. After 8 hours, LPS-exposed rats had significantly higher dialysate levels of all investigated cytokines (TNF-alfa, MCP-1 and IL-10) than the control group. Addition of LPS resulted in increased dialysate VEGF concentrations (pg/mL) (LPS 0.001, 28.2+/-5.9; LPS 0.01, 38.9+/-11.6; LPS 0.1, 43.0+/-5.9; LPS 1.0, 46.6+/-11.3; Control, 14.5+/-9.8; p<0.0005 for all LPS vs. Control).<h4>Conclusions</h4>The infusion of Dianeal 3.86% with different doses of LPS induced a strong acute intraperitoneal inflammatory reaction with increased DCC and cytokine levels, resulting in increased peritoneal solute transport and decreased IPV. LPS induced a dose-dependent parallel increase of the intraperitoneal concentrations of MCP-1, IL-10 and TNF-alfa, as well as of VEGF. These results suggest that intraperitoneal VEGF synthesis is induced in response to inflammation, and that this may be an important component in the process leading to peritoneal transport alterations.

Also flagged:Alanine-transaminaseALTinfectionchronic active hepatitischronic liver diseaseautoimmune chronic hepatitis
Journal Article 2008-06-01 ✓ 1 Snippet Sobesky R, Lebray P, Nalpas B, Vallet-Pichard A, Fontaine H, Lagneau JL, Pol S.
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hemochromatosis

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<h4>Aim</h4>To determine factors associated with fibrosis progression in hepatitis C virus (HCV)-infected patients without significant initial pathological lesions.<h4>Methods</h4>Seventy six untreated HCV-infected patients with initially normal liver as defined by a Knodell score < or = 3, with 2 liver biopsies and detectable HCV-RNA were included. Markers of fibrosis progression were assessed.<h4>Results</h4>Median duration of infection and time between paired biopsies was 13 (95% CI: 1-28) and 4 (95% CI: 2-16) years respectively. Alanine-transaminase (ALT) activity was normal in 43.4% of cases. 50% demonstrated progression of the necro-inflammation and 34% of fibrosis after a median time evolution of 4 years (95% CI: 2-16). The median difference in the necro-inflammation and fibrosis score between biopsies was low, 1.5 and 0.0 respectively. Univariate analysis showed there was no difference between fibrosis activity or evolution according to genotype or viral load. A higher fibrosis progression (P = 0.03) was observed in patients with body mass index (BMI) > 25. Fibrosis progression correlated with the time interval between biopsies (P = 0.01). A significant progression of activity (1.7 vs 0.4, P < 0.05) or fibrosis (0.9 vs 0.0, P < 0.01) was observed in patients with elevated ALT. There was a significant correlation between activity progression and fibrosis progression (P = 0.003). Multivariate analysis demonstrated that fibrosis progression was associated with elevated ALT, BMI > 25 and the time interval between 2 biopsies.<h4>Conclusion</h4>There is no fibrosis progression in 66% of patients without significant initial histopathological lesion. Fibrosis progression is associated with elevated ALT and BMI > 25.

Also flagged:diabetesgastroparesisintestinal enteropathyfecal incontinencenonalcoholic fatty liver diseasediabetic gastroparesis
Journal Article 2008-06-01 ✓ 1 Snippet Shakil A, Church RJ, Rao SS.
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…including hepatitis andhemochromatosis.…

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Gastrointestinal complications of diabetes include gastroparesis, intestinal enteropathy (which can cause diarrhea, constipation, and fecal incontinence), and nonalcoholic fatty liver disease. Patients with gastroparesis may present with early satiety, nausea, vomiting, bloating, postprandial fullness, or upper abdominal pain. The diagnosis of diabetic gastroparesis is made when other causes are excluded and postprandial gastric stasis is confirmed by gastric emptying scintigraphy. Whenever possible, patients should discontinue medications that exacerbate gastric dysmotility; control blood glucose levels; increase the liquid content of their diet; eat smaller meals more often; discontinue the use of tobacco products; and reduce the intake of insoluble dietary fiber, foods high in fat, and alcohol. Prokinetic agents (e.g., metoclopramide, erythromycin) may be helpful in controlling symptoms of gastroparesis. Treatment of diabetes-related constipation and diarrhea is aimed at supportive measures and symptom control. Nonalcoholic fatty liver disease is common in persons who are obese and who have diabetes. In persons with diabetes who have elevated hepatic transaminase levels, it is important to search for other causes of liver disease, including hepatitis and hemochromatosis. Gradual weight loss, control of blood glucose levels, and use of medications (e.g., pioglitazone, metformin) may normalize hepatic transaminase levels, but the clinical benefit of aggressively treating nonalcoholic fatty liver disease is unknown. Controlling blood glucose levels is important for managing most gastrointestinal complications.

Also flagged:strokeacute strokeCNS infectionantithrombin IIIprotein Cprotein S
Journal Article 2008-06-01 ✓ 1 Snippet Makhija S, Aneja S, Tripathi RP, Narayan S.
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…(11.1%), vasculitis (5.5%),ATIIIdeficiency (5.5%), Protein…

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<h4>Objective</h4>To study the etiological profile of childhood stroke and its relation with prothrombotic states.<h4>Methods</h4>Children with acute stroke with no evidence of CNS infection or head injury were studied. Stroke was confirmed by CT scan and further evaluated by MRI. Cardiac status was assessed with transthoracic echocardiography. Test for hypercoagulable state (antithrombin III, protein C, protein S, anticardiolipin antibody IgG and IgM and lupus anticoagulant) were done in all patients.<h4>Results</h4>A total of 66 children were enrolled--36 cases and 30 controls. Presenting symptoms were motor deficit (72%), seizure (66%), altered sensorium (36%), aphasia (27%). Causes identified were antiphospholipid antibody syndrome (25%), Moya Moya disease (16.6%), cardiac disease (11.1%), vasculitis (5.5%), ATIII deficiency (5.5%), Protein C deficiency (2.7%). Etiology remained unknown in 25% of cases with infarction. Hemorrhage was seen in 8.2% of cases and they had DIC or liver disease as the underlying cause.<h4>Conclusions</h4>Magnetic Resonance Angiography and ELISA for antiphospholipid antibody should be done in all patients with stroke without an obvious cause.

Also flagged:neurological diseasesbehavioralCognitive impairmentschizophreniasleepdrug addiction
Journal Article 2008-06-01 ✓ 1 Snippet Best JD, Alderton WK.
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In zebrafish, the huntingtin (Htt) gene has been cloned and sequenced with a 3121 predicted amino acid protein, which has 70% identity with the human peptide sequence (Karlovich et al 1998).

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As the population ages, there is a growing need for effective therapies for the treatment of neurological diseases. A limited number of therapeutics are currently available to improve cognitive function and research is limited by the need for in vivo models. Zebrafish have recently become a focus of neurobehavioral studies since larvae display neuropathological and behavioral phenotypes that are quantifiable and relate to those seen in man. Due to the small size of Zebrafish larvae, assays can be undertaken in 96 well plates and as the larvae can live in as little as 200 mul of fluid, only a few milligrams of compound are needed for screening. Thus in vivo analysis of the effects of compounds can be undertaken at much earlier stages in the drug discovery process. This review will look at the utility of the zebrafish in the study of neurological diseases and its role in improving the throughput of candidate compounds in in vivo screens.

Also flagged:Oxytocin ReceptorOXTRSerotoninbehaviorsocial behaviorautism
Journal Article 2008-06-01 ✓ 1 Snippet Taylor SE.
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HTT

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No abstract available.

Also flagged:prostacyclin synthasemyocardial infarctionMI6-keto-COX-2keto
Journal Article 2008-06-01 No Snippets Xie X, Ma YT, Fu ZY, Yang YN, Wang YH, Chen BD, Liu F.
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<h4>Objective</h4>The purpose of this study was to investigate the association of genetic polymorphism of cyclooxygenase-2 and prostacyclin synthase with myocardial infarction (MI) in Uigur population in Xinjiang.<h4>Methods</h4>178 patients with MI and 175 healthy control subjects were detected on the genetic polymorphism of cyclooxygenase-2 and prostacyclin synthase by polymerase chain reaction-based restriction fragment length polymorphism. Other serum 6-keto-PGF1alpha concentration and biochemical indicators were detected in all the subjects.<h4>Results</h4>(1) The genotype distributions of the control group and MI group were in the Hardy-Weinberg equilibrium. The frequencies of CC, CA and AA genotype of prostacyclin synthase were 75.84%, 17.42% and 6.74% in MI group while they were 64.57%, 28.29% and 9.14% in controls respectively. There was significant difference in frequencies of CC genotype and C allele as well as CA and AA genotypes between controls and MI cases. (2) The frequencies of -765GG, -765GC and -765CC genotype of cyclooxygenase-2 were 78.65%, 19.66% and 1.69% in MI group while they were 55.43%, 34.86% and 9.71% in controls respectively. There was significant difference in frequencies of three genotypes and alleles between the two groups (P < 0.05 or P < 0.01). (3) In combined genotype analysis, the genotype of PGIS CC + COX-2 -765GG was significantly higher in patients with MI than in control subjects (P < 0.05). The odds ratio estimated through combined analysis of the PGIS CC and COX-2 -765GG genotypes (OR = 3.87) markedly increased when compared with that estimated separately from the PGIS CC (OR = 1.72) or COX-2 -765GG (OR = 2.94) genotype. (4) There was a significant difference in serum 6-keto-PGF1alpha level between MI group and control group (P < 0.05), but there were no differences found in every genotype of PGIS and COX-2 gene (P > 0.05). In the cases with both COX-2 -765GG and PGIS CC genotypes, the serum 6-keto-PGF1alpha levels was lower than that of others (P < 0.05).<h4>Conclusion</h4>The CC genotype and C allele of prostacyclin synthase, -765GG genotype and G allele of COX-2 might serve as risk factors of MI of Uigur population in Xinjiang. Populations with both COX-2 -765GG and PGIS CC genotypes were more at risk with MI than others which might be resulted from the decreased serum 6-keto-PGF1alpha concentration. The -765CC genotype and C allele of COX-2 gene might have protective functions on MI among Uigur population in Xinjiang.

Also flagged:axonsaxonalspinal cord injurybrain developmentmyelin-associated proteinsbrain injuries
Journal Article 2008-06-01 No Snippets Ueno M, Yamashita T.
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Axonal regeneration does not occur easily after an adult central nervous system (CNS) injury. Various attempts have partially succeeded in promoting axonal regeneration after the spinal cord injury (SCI). Interestingly, several recent therapeutic concepts have emerged from or been tightly linked to the researches on brain development. In a developing brain, remarkable and dynamic axonal elongation and sprouting occur even after the injury; this finding is essential to the development of a therapy for SCI. In this review, we overview the revealed mechanism of axonal tract formation and plasticity in the developing brain and compare the differences between a developing brain and a lesion site in an adult brain. One of the differences is that mature glial cells participate in the repair process in the case of adult injuries. Interestingly, these cells express inhibitory molecules that impede axonal regeneration such as myelin-associated proteins and the repulsive guidance molecules found originally in the developing brain for navigating axons to specific routes. Some reports have clearly elucidated that any treatment designed to suppress these inhibitory cues is beneficial for promoting regeneration and plasticity after an injury. Thus, understanding the developmental process will provide us with an important clue for designing therapeutic strategies for recovery from SCI.

Also flagged:Hepatocellular CarcinomaWilson Disease-related Liver CirrhosisWDmetabolic disorderchromosomecopper-transporting P-type ATPase
Journal Article 2008-06-01 ✓ 1 Snippet Reyes CV.
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hemochromatosis

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No abstract available.

Also flagged:SiliconCalcium Phosphatecalcium phosphatesapatitedegenerative diseaserhBMP-2
Journal Article 2008-06-01 No Snippets Pimenta L, Pesántez CF, Oliveira L.
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<h4>Introduction</h4>Autograft has been the "gold standard" for orthopedic bone grafting applications, but with some clinical challenges. Here we present the rationale and clinical outcomes supporting the use of a bone substitute material that consists of a mixture of two calcium phosphates (HA and ß-TCP), which are integrated into a silicon xerogel matrix, promoting nanocrystalline apatite layers on the surface of the material following implantation into a physiological environment.<h4>Methods</h4>Twenty-four patients with a median age of 53.80 (36-81) years underwent lumbar spinal fusion for degenerative disease, selected by clinical presentation, X-rays, and MRI findings. Subjects were evaluated preoperatively and postoperatively at 1, 3, 6, and 12 months. The outcome assessment consisted of visual analog scale (VAS), Oswestry Disability Index (ODI), and radiological assessment analyzing the state of fusion on X-ray and CT evaluation by 3 independent radiologists.<h4>Results</h4>All patients completed 12-month follow-up. The mean VAS decreased from 9.3 (± 0.9) to 2.4 (± 1.6) and the mean ODI decreased from 55.0 (± 9.2) to 19.3 (± 11.4) at 12-month follow-up. Three months after surgery, 10 patients (41.67%) had solid fusion based on analysis of CT scans and dynamic radiographs. At 6 months postoperatively, the fusion rate had increased to 75% (18 patients). Twelve months after surgery, 95.83% of patients had solid fusion (23 patients).<h4>Conclusions</h4>The clinical results from this study of silicon matrix calcium phosphate are consistent with previous in vitro studies indicating that this material stimulates formation of a bioactive layer and provides an effective bone graft material for lumbar fusion applications. In comparison with previous studies involving rhBMP-2, silicon matrix calcium phosphate provided a lower fusion rate at 3- and 6-month follow-up points, but after 12 months, the fusion rate was similar, with no statistical differences and lower overall costs. No clinically relevant adverse events were associated with either the cage or graft material. With increasing evidence of high rates of enhanced fusion development in this spinal application, additional research is encouraged, including longer periods of followup, to further confirm the efficacy of silicon matrix calcium phosphate as a safe and effective bone graft substitute.