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Viewing September 2006 — 87 paper(s) from the local store. (Local view only — run without --view to fetch new papers.)
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Also flagged:hereditary hemochromatosisiron
Journal Article 2006-09-30 ✓ 4 Snippets Aranda N, Viteri FE, Fernández-Ballart J, Murphy M, Arija V.
In-Text Gene Mentions

Frequency of the hemochromatosis gene (HFE) 282C-->Y, 63H-->D, and 65S-->C mutations in a general Mediterranean population from Tarragona, Spain.

…Frequency of thehemochromatosisgene (HFE) 282C-->Y,…

…the hemochromatosis gene (HFE) 282C-->Y, 63H-->D, and…

…the hereditary hemochromatosisHFEgene (282C-->Y, 63H-->D,…

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Three mutations have recently been detected in the hereditary hemochromatosis HFE gene (282C-->Y, 63H-->D, and 65S-->C). To determine their prevalence in a northeastern Spanish Mediterranean population, we studied 812 subjects between 18 and 75 years of age, randomly selected from the electoral roll of three villages. There were no homozygotes for the 282C-->Y or S65D mutations in this sample. For the 63H-->D mutation, 4.8% were homozygotes; 4.3, 32.3, and 2% were heterozygotes for the 282C-->Y, 63H-->D, and 65S-->C mutations, respectively. The prevalence of compound heterozygotes was 2% for 282C-->Y/63H-->D and 0.6% for 63H-->D /65S-->C. We found no significant differences between men and women. In conclusion, 46% of this Mediterranean population of Spain are carriers of at least one of the three mutations that can increase iron absorption.

Also flagged:uridineHuntington's diseaseacetyluridinemitochondrial complex II3-nitropropionic acidHD
Journal Article 2006-09-29 No Snippets Saydoff JA, Garcia RA, Browne SE, Liu L, Sheng J, Brenneman D, Hu Z, Cardin S, Gonzalez A, von Borstel RW, Gregorio J, Burr H, Beal MF.
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Previously, uridine pro-drug 2',3',5'-tri-O-acetyluridine (PN401) was shown to be protective in the mitochondrial complex II inhibitor 3-nitropropionic acid model of Huntington's disease (HD). In this study, PN401 increased survival and improved motor function on the rotarod in both R6/2 and N171-82Q polyglutamine repeat mouse models of HD. PN401 significantly decreased neurodegeneration in both the piriform cortex and striatum although PN401 decreased huntingtin protein aggregates only in the striatum. Cortical and striatal brain-derived neurotrophic factor (BDNF) protein levels were reduced in the +/- compared to the -/- N171-82Q mice and PN401 treatment significantly increased cortical BDNF in both +/- and -/- mice, but PN401 did not affect striatal BDNF. These results suggest that PN401 may have beneficial effects in the treatment of neurodegenerative diseases such as HD.

Also flagged:Huntington diseaseHDadult-onsetneurodegenerative diseasepolyglutaminepathogenesis
Journal Article 2006-09-29 ✓ 5 Snippets Cornett J, Smith L, Friedman M, Shin JY, Li XJ, Li SH.
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Our results provide insight into the beneficial effects of molecular chaperones and suggest that context dependent transcriptional dysregulation may contribute to differential toxicity of various N-terminal htt fragments.

Huntington disease (HD) is an adult-onset neurodegenerative disease caused by expansion of a polyglutamine (poly(Q) tract in the N-terminal region of huntingtin (htt).

In HD, multiple N-terminal mutant htt fragments smaller than the first 500 amino acids have been found to accumulate in the nucleus and adversely affect gene transcription.

…region of huntingtin (htt).…

…multiple N-terminal mutanthttfragments smaller than…

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Huntington disease (HD) is an adult-onset neurodegenerative disease caused by expansion of a polyglutamine (poly(Q) tract in the N-terminal region of huntingtin (htt). Although the precise mechanisms leading to neurodegeneration in HD have not been fully elucidated, transcriptional dysregulation has been implicated in disease pathogenesis. In HD, multiple N-terminal mutant htt fragments smaller than the first 500 amino acids have been found to accumulate in the nucleus and adversely affect gene transcription. It is unknown whether different htt fragments in the nucleus can differentially bind transcription factors and affect transcription. Here, we report that shorter N-terminal htt fragments, which are more prone to misfolding and aggregation, are more competent to bind Sp1 and inhibit its activity. These effects can be reversed by Hsp40, a molecular chaperone that reduces the misfolding of mutant htt. Our results provide insight into the beneficial effects of molecular chaperones and suggest that context dependent transcriptional dysregulation may contribute to differential toxicity of various N-terminal htt fragments.

Also flagged:reverse transcriptaseTriphosphatesynthesisnucleosidetriphosphateslipase
Journal Article 2006-09-29 No Snippets Siddiqui MA, Marquez VE.
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The enantioselective synthesis of the beta-d (1) enantiomer of 4'-C-ethynyl-2',3'-dideoxycytidine confirms an earlier stereochemical assignment that was strictly based on the ability of HIV reverse transcriptase and its M184V mutant to discriminate between the d- and l-configuration of nucleoside 5'-triphosphates.

Also flagged:antibodyGlycyrrhizic acidglycyrrhetic acidGLBSAhepatitis
Journal Article 2006-09-28 No Snippets Zhao J, Li G, Wang BM, Liu W, Nan TG, Zhai ZX, Li ZH, Li QX.
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Glycyrrhizic acid (GL) is a major active compound of licorice. The specific monoclonal antibody (MAb) (designated as 8F8A8H42H7) against GL was produced with the immunogen GL-BSA conjugate. The dissociation constant (Kd) value of the MAb was approximately 9.96x10(-10) M. The cross reactivity of the MAb with glycyrrhetic acid was approximately 2.6%. The conventional indirect competitive enzyme-linked immunosorbent assay (icELISA) and simplified icELISA adapted with a modified procedure were established using the MAb. The IC50 value and the detect range by the conventional icELISA were 1.1 ng mL-1 and 0.2-5.1 ng mL-1, respectively. The IC50 value and the detect range by the simplified icELISA were 5.3 ng mL-1 and 1.2-23.8 ng mL-1, respectively. The two icELISA formats were used to analyze GL contents in the roots of wild licorice and different parts of cultivated licorice (Glycyrrhiza uralensis Fisch). The results obtained with the two icELISAs agreed well with those of the HPLC analysis. The correlation coefficient was more than 0.98 between HPLC and the two icELISAs. The two icELISAs were shown to be appropriate, simple, and effective for the quality control of raw licorice root materials.

Also flagged:N-cadherinOptimedinolfactomedin 3olfactomedin domainPax6tetracycline
Journal Article 2006-09-28 ✓ 1 Snippet Lee HS, Tomarev SI.
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OLFM4

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Optimedin, also known as olfactomedin 3, belongs to a family of olfactomedin domain-containing proteins. It is expressed in neural tissues and Pax6 is involved in the regulation of its promoter. To study possible effects of optimedin on the differentiation of neural cells, we produced stably transfected PC12 cell lines expressing optimedin under a tetracycline-inducible promoter. Cells expressing high levels of optimedin showed higher growth rates and stronger adhesion to the collagen extracellular matrix as compared with control PC12 cells. After stimulation with nerve growth factor (NGF), optimedin-expressing cells demonstrated elevated levels of N-cadherin, beta-catenin, alpha-catenin and occludin as compared with stimulated, control PC12 cells. Expression of optimedin induced Ca(2+)-dependent aggregation of NGF-stimulated PC12 cells and this aggregation was blocked by the expression of N-cadherin siRNA. Expression of optimedin also changed the organization of the actin cytoskeleton and inhibited neurite outgrowth in NGF-stimulated PC12 cells. We suggest that expression of optimedin stimulates the formation of adherent and tight junctions on the cell surface and this may play an important role in the differentiation of the brain and retina through the modulation of cytoskeleton organization, cell-cell adhesion and migration.

Also flagged:multiple myelomamyelodysplastic syndromeironmetabolismmyelodysplasia
Journal Article 2006-09-26 ✓ 5 Snippets Várkonyi J, Demeter J, Tordai A, Andrikovics H.
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We found significant differences in the frequencies of the HFE genetic variants between MDS and MM patients with strong correlation to their iron metabolism.

The clinical experience of the significant difference in iron metabolism between multiple myeloma and myelodysplasia prompted us to analyse patients according to mutation frequency in the hemochromatosis gene (HFE) known to participate in the regulation of iron metabolism.

49 patients with MM were compared to 61 patients with myelodysplastic syndrome (MDS) concerning the incidence of two genetic variants of the HFE gene (C282Y and H63D) identified with PCR-RFLP.

HFE genotyping results were also evaluated in view of the clinical data in multiple myeloma (MM) patients.

The initial WBC were significantly lower in the minority of MM patients who were at the same time heterozygous for the HFE gene variants.

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The clinical experience of the significant difference in iron metabolism between multiple myeloma and myelodysplasia prompted us to analyse patients according to mutation frequency in the hemochromatosis gene (HFE) known to participate in the regulation of iron metabolism. HFE genotyping results were also evaluated in view of the clinical data in multiple myeloma (MM) patients. 49 patients with MM were compared to 61 patients with myelodysplastic syndrome (MDS) concerning the incidence of two genetic variants of the HFE gene (C282Y and H63D) identified with PCR-RFLP. Data of serum iron, transferrin saturation, consumed blood units and initial white blood cell counts (WBC) were analysed in relation to the HFE genotype status. 30 out of the 61 MDS patients (49%) and only 9 out of the 49 MM patients (20%) were positive for either HFE variant. Serum iron and transferrin saturation levels were all normal in MM and elevated in MDS patients. The initial WBC were significantly lower in the minority of MM patients who were at the same time heterozygous for the HFE gene variants. We found significant differences in the frequencies of the HFE genetic variants between MDS and MM patients with strong correlation to their iron metabolism. The low WBC in HFE positive MM patients unrelated to bone marrow infiltration rate might raise the suspicion of co-existent myelodysplasia.

Also flagged:Helicobacter pylori infectionHelicobacter pylori infectionsiron deficiencyH. pylori infectioniron
Journal Article 2006-09-25 ✓ 4 Snippets Beutler E, Gelbart T.
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Helicobacter pylori infection and HFE hemochromatosis.

To determine whether H. pylori infection plays a role in modifying the phenotype of patients homozygous for the c.845 G > A (C282Y) mutation of the HFE gene we studied 79 homozygous women and 76 homozygous men, comparing the pretreatment hemoglobin, MCV, serum ferritin, transferrin saturation of those who were seropositive and seronegative for H. pylori.

…pylori infection andHFE hemochromatosishemochromatosis.…

…mutation of theHFEgene we studied…

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Helicobacter pylori infections are associated with iron deficiency, even in the absence of bleeding. To determine whether H. pylori infection plays a role in modifying the phenotype of patients homozygous for the c.845 G > A (C282Y) mutation of the HFE gene we studied 79 homozygous women and 76 homozygous men, comparing the pretreatment hemoglobin, MCV, serum ferritin, transferrin saturation of those who were seropositive and seronegative for H. pylori. No difference between seropositive and seronegative homozytoes was found. There was also no difference between seropositive and seronegative control subjects. We also compared the total iron of 56 of the male and 32 of the female homozygotes as determined by serial phlebotomy. No significant difference was found.

Also flagged:DbsRho-specific guanine nucleotide exchange factorRhoGEFRhoACdc42scaffold protein
Journal Article 2006-09-25 ✓ 5 Snippets Kostenko EV, Olabisi OO, Sahay S, Rodriguez PL, Whitehead IP.
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Ccpg1, a novel scaffold…

…progression protein 1 [Ccpg1]) that interacts with…

…in mammalian cells,Ccpg1binds to the…

…Expression ofCcpg1correlates with the…

…suppression of endogenousCcpg1expression potentiates Dbs…

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Dbs is a Rho-specific guanine nucleotide exchange factor (RhoGEF) with in vitro exchange activity specific for RhoA and Cdc42. Like many RhoGEF family members, the in vivo exchange activity of Dbs is restricted in a cell-specific manner. Here we report the characterization of a novel scaffold protein (designated cell cycle progression protein 1 [Ccpg1]) that interacts with Dbs and modulates its in vivo exchange specificity. When coexpressed in mammalian cells, Ccpg1 binds to the Dbl homology/pleckstrin homology domain tandem motif of Dbs and inhibits its exchange activity toward RhoA, but not Cdc42. Expression of Ccpg1 correlates with the ability of Dbs to activate endogenous RhoA in cultured cells, and suppression of endogenous Ccpg1 expression potentiates Dbs exchange activity toward RhoA. The isolated Dbs binding domain of Ccpg1 is not sufficient to suppress Dbs exchange activity on RhoA, thus suggesting a regulatory interaction. Ccpg1 mediates recruitment of endogenous Src kinase into Dbs-containing complexes and interacts with the Rho family member Cdc42. Collectively, our studies suggest that Ccpg1 represents a new class of regulatory scaffold protein that can function as both an assembly platform for Rho protein signaling complexes and a regulatory protein which can restrict the substrate utilization of a promiscuous RhoGEF family member.

Also flagged:ring finger E3 ligaseRING finger ubiquitin ligaseSiah2PHD3phosphorylationp38 MAPK
Journal Article 2006-09-25 No Snippets Khurana A, Nakayama K, Williams S, Davis RJ, Mustelin T, Ronai Z.
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The RING finger ubiquitin ligase Siah2 controls the stability of various substrates involved in stress and hypoxia responses, including the PHD3, which controls the stability of HIF-1alpha. In the present study we determined the role of Siah2 phosphorylation in the regulation of its activity toward PHD3. We show that Siah2 is subject to phosphorylation by p38 MAPK, which increases Siah2-mediated degradation of PHD3. Consistent with these findings, MKK3/MKK6 double-deficient cells, which cannot activate p38 kinases, exhibit impaired Siah2-dependent degradation of PHD3. Phosphopeptide mapping identified T24 and S29 as the primary phospho-acceptor sites. Phospho-mutant forms of Siah2 (S29A or T24A/S29A) exhibit impaired degradation of PHD3, particularly after hypoxia. Conversely, a phospho-mimic form of Siah2 (T24E/S29D) exhibits stronger degradation of PHD3, compared with wild type Siah2. Whereas phospho-mutant Siah2 exhibits weaker association with PHD3, phospho-mimic Siah2 associates as well as wild type and is localized within the perinuclear region, suggesting that phosphorylation of Siah2 affects its subcellular localization and, consequently, the degree of its association with PHD3. In all, our findings reveal the phosphorylation of Siah2 by p38 and the implications of such phosphorylation for Siah2 activity toward PHD3.

Also flagged:Repo-ManPP1chromosomemitosisSMC2H2B
Journal Article 2006-09-24 ✓ 1 Snippet Vagnarelli P, Hudson DF, Ribeiro SA, Trinkle-Mulcahy L, Spence JM, Lai F, Farr CJ, Lamond AI, Earnshaw WC.
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Condensinand Repo-Man/PP1 co-operate…

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The reversible condensation of chromosomes during cell division remains a classic problem in cell biology. Condensation requires the condensin complex in certain experimental systems, but not in many others. Anaphase chromosome segregation almost always fails in condensin-depleted cells, leading to the formation of prominent chromatin bridges and cytokinesis failure. Here, live-cell analysis of chicken DT40 cells bearing a conditional knockout of condensin subunit SMC2 revealed that condensin-depleted chromosomes abruptly lose their compact architecture during anaphase and form massive chromatin bridges. The compact chromosome structure can be preserved and anaphase chromosome segregation rescued by preventing the targeting subunit Repo-Man from recruiting protein phosphatase 1 (PP1) to chromatin at anaphase onset. This study identifies an activity critical for mitotic chromosome structure that is inactivated by Repo-Man-PP1 during anaphase. This activity, provisionally termed 'regulator of chromosome architecture' (RCA), cooperates with condensin to preserve the characteristic chromosome architecture during mitosis.

Also flagged:Cell surfacenucleolinreceptor tyrosine phosphatasesaxonalphosphataseaxon
Journal Article 2006-09-21 ✓ 1 Snippet Alete DE, Weeks ME, Hovanession AG, Hawadle M, Stoker AW.
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DCC

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Reversible tyrosine phosphorylation, catalyzed by receptor tyrosine kinases and receptor tyrosine phosphatases, plays an essential part in cell signaling during axonal development. Receptor protein tyrosine phosphatase-sigma has been implicated in the growth, guidance and repair of retinal axons. This phosphatase has also been implicated in motor axon growth and innervation. Insect orthologs of receptor protein tyrosine phosphatase-sigma are also implicated in the recognition of muscle target cells. A potential extracellular ligand for vertebrate receptor protein tyrosine phosphatase-sigma has been previously localized in developing skeletal muscle. The identity of this muscle ligand is currently unknown, but it appears to be unrelated to the heparan sulfate ligands of receptor protein tyrosine phosphatase-sigma. In this study, we have used affinity chromatography and tandem MS to identify nucleolin as a binding partner for receptor protein tyrosine phosphatase-sigma in skeletal muscle tissue. Nucleolin, both from tissue lysates and in purified form, binds to receptor protein tyrosine phosphatase-sigma ectodomains. Its expression pattern also overlaps with that of the receptor protein tyrosine phosphatase-sigma-binding partner previously localized in muscle, and nucleolin can also be found in retinal basement membranes. We demonstrate that a significant amount of muscle-associated nucleolin is present on the cell surface of developing myotubes, and that two nucleolin-binding components, lactoferrin and the HB-19 peptide, can block the interaction of receptor protein tyrosine phosphatase-sigma ectodomains with muscle and retinal basement membranes in tissue sections. These data suggest that muscle cell surface-associated nucleolin represents at least part of the muscle binding site for axonal receptor protein tyrosine phosphatase-sigma and that nucleolin may also be a necessary component of basement membrane binding sites of receptor protein tyrosine phosphatase-sigma.

Also flagged:Huntington's diseaseHDneurodegenerative disorderIT15deathvesicular acetylcholine transporter
Journal Article 2006-09-20 No Snippets Smith R, Chung H, Rundquist S, Maat-Schieman ML, Colgan L, Englund E, Liu YJ, Roos RA, Faull RL, Brundin P, Li JY.
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Huntington's disease (HD) is a neurodegenerative disorder caused by a CAG-repeat expansion in the huntingtin (IT15) gene. The striatum is one of the regions most affected by neurodegeneration, resulting in the loss of the medium-sized spiny neurons. Traditionally, the large cholinergic striatal interneurons are believed to be spared. Recent studies demonstrate that neuronal dysfunction without cell death also plays an important role in early and mid-stages of the disease. Here, we report that cholinergic transmission is affected in a HD transgenic mouse model (R6/1) and in tissues from HD patients. Stereological analysis shows no loss of cholinergic neurons in the striatum or septum in R6/1 mice. In contrast, the levels of mRNA and protein for vesicular acetylcholine transporter (VAChT) and choline acetyltransferase (ChAT) are decreased in the striatum and cortex, and acetylcholine esterase activity is lowered in the striatum of R6/1 mice already at young ages. Accordingly, VAChT is also reduced in striatal tissue from patients with HD. The decrease of VAChT in the patient samples studied is restricted to the striatum and does not occur in the hippocampus or the spinal cord. The expression and localization of REST/NRSF, a transcriptional regulator for the VAChT and ChAT genes, are not altered in cholinergic neurons. We show that the R6/1 mice exhibit severe deficits in learning and reference memory. Taken together, our data show that the cholinergic system is dysfunctional in R6/1 and HD patients. Consequently, they provide a rationale for testing of pro-cholinergic drugs in this disease.

Also flagged:transcription factorATF3chondrocyte differentiationcyclin D1Transcription factorsbinding
Journal Article 2006-09-19 ✓ 1 Snippet James CG, Woods A, Underhill TM, Beier F.
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…related L-Sox5 andSox6proteins, controls chondrocyte…

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<h4>Background</h4>Coordinated chondrocyte proliferation and differentiation are required for normal endochondral bone growth. Transcription factors binding to the cyclicAMP response element (CRE) are known to regulate these processes. One member of this family, Activating Transcription Factor 3 (ATF3), is expressed during skeletogenesis and acts as a transcriptional repressor, but the function of this protein in chondrogenesis is unknown.<h4>Results</h4>Here we demonstrate that Atf3 mRNA levels increase during mouse chondrocyte differentiation in vitro and in vivo. In addition, Atf3 mRNA levels are increased in response to cytochalasin D treatment, an inducer of chondrocyte maturation. This is accompanied by increased Atf3 promoter activity in cytochalasin D-treated chondrocytes. We had shown earlier that transcription of the cell cycle genes cyclin D1 and cyclin A in chondrocytes is dependent on CREs. Here we demonstrate that overexpression of ATF3 in primary mouse chondrocytes results in reduced transcription of both genes, as well as decreased activity of a CRE reporter plasmid. Repression of cyclin A transcription by ATF3 required the CRE in the cyclin A promoter. In parallel, ATF3 overexpression reduces the activity of a SOX9-dependent promoter and increases the activity of a RUNX2-dependent promoter.<h4>Conclusion</h4>Our data suggest that transcriptional induction of the Atf3 gene in maturing chondrocytes results in down-regulation of cyclin D1 and cyclin A expression as well as activation of RUNX2-dependent transcription. Therefore, ATF3 induction appears to facilitate cell cycle exit and terminal differentiation of chondrocytes.

Also flagged:Gallium1gallium mononitrilotriacetatetransferrin receptor 1apotransferrinbicarbonate
Journal Article 2006-09-19 No Snippets Chikh Z, Ha-Duong NT, Miquel G, El Hage Chahine JM.
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The kinetics and thermodynamics of Ga(III) exchange between gallium mononitrilotriacetate and human serum transferrin as well as those of the interaction between gallium-loaded transferrin and the transferrin receptor 1 were investigated in neutral media. Gallium is exchanged between the chelate and the C-site of human serum apotransferrin in interaction with bicarbonate in about 50 s to yield an intermediate complex with an equilibrium constant K (1) = (3.9 +/- 1.2) x 10(-2), a direct second-order rate constant k (1) = 425 +/- 50 M(-1) s(-1) and a reverse second-order rate constant k (-1) = (1.1 +/- 3) x 10(4) M(-1) s(-1). The intermediate complex loses a single proton with proton dissociation constant K (1a) = 80 +/- 40 nM to yield a first kinetic product. This product then undergoes a modification in its conformation which lasts about 500 s to produce a second kinetic intermediate, which in turn undergoes a final extremely slow (several hours) modification in its conformation to yield the gallium-saturated transferrin in its final state. The mechanism of gallium uptake differs from that of iron and does not involve the same transitions in conformation reported during iron uptake. The interaction of gallium-loaded transferrin with the transferrin receptor occurs in a single very fast kinetic step with a dissociation constant K (d) = 1.10 +/- 0.12 microM and a second-order rate constant k (d) = (1.15 +/- 0.3) x 10(10) M(-1) s(-1). This mechanism is different from that observed with the ferric holotransferrin and suggests that the interaction between the receptor and gallium-loaded transferrin probably takes place on the helical domain of the receptor which is specific for the C-site of transferrin and HFE. The relevance of gallium incorporation by the transferrin receptor-mediated iron-acquisition pathway is discussed.

Also flagged:psychiatric illnesspsychiatric diseaseglucosepathogenesispsychiatric disordersschizophrenia
Journal Article 2006-09-18 ✓ 2 Snippets Flint J, Munafò MR.
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…transporter gene (5-HTT) was associated…

…allele at the5-HTTgene promoter were…

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The idea that some phenotypes bear a closer relationship to the biological processes that give rise to psychiatric illness than diagnostic categories has attracted considerable interest. Much effort has been devoted to finding such endophenotypes, partly because it is believed that the genetic basis of endophenotypes will be easier to analyse than that of psychiatric disease. This belief depends in part on the assumption that the effect sizes of genetic loci contributing to endophenotypes are larger than those contributing to disease susceptibility, hence increasing the chance that genetic linkage and association tests will detect them. We examine this assumption by applying meta-analytical techniques to genetic association studies of endophenotypes. We find that the genetic effect sizes of the loci examined to date are no larger than those reported for other phenotypes. A review of the genetic architecture of traits in model organisms also provides no support for the view that the effect sizes of loci contributing to phenotypes closer to the biological basis of disease is any larger than those contributing to disease itself. While endophenotype measures may afford greater reliability, it should not be assumed that they will also demonstrate simpler genetic architecture.

Also flagged:immune responsetumourextracellular spaceangiogenesisorganizationgenes expression
Journal Article 2006-09-18 No Snippets Re A, Cora D, Puliti AM, Caselle M, Sbrana I.
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<h4>Background</h4>Common fragile sites (cfs) are specific regions in the human genome that are particularly prone to genomic instability under conditions of replicative stress. Several investigations support the view that common fragile sites play a role in carcinogenesis. We discuss a genome-wide approach based on graph theory and Gene Ontology vocabulary for the functional characterization of common fragile sites and for the identification of genes that contribute to tumour cell biology.<h4>Results</h4>Common fragile sites were assembled in a network based on a simple measure of correlation among common fragile site patterns of expression. By applying robust measurements to capture in quantitative terms the non triviality of the network, we identified several topological features clearly indicating departure from the Erdos-Renyi random graph model. The most important outcome was the presence of an unexpected large connected component far below the percolation threshold. Most of the best characterized common fragile sites belonged to this connected component. By filtering this connected component with Gene Ontology, statistically significant shared functional features were detected. Common fragile sites were found to be enriched for genes associated to the immune response and to mechanisms involved in tumour progression such as extracellular space remodeling and angiogenesis. Moreover we showed how the internal organization of the graph in communities and even in very simple subgraphs can be a starting point for the identification of new factors of instability at common fragile sites.<h4>Conclusion</h4>We developed a computational method addressing the fundamental issue of studying the functional content of common fragile sites. Our analysis integrated two different approaches. First, data on common fragile site expression were analyzed in a complex networks framework. Second, outcomes of the network statistical description served as sources for the functional annotation of genes at common fragile sites by means of the Gene Ontology vocabulary. Our results support the hypothesis that fragile sites serve a function; we propose that fragility is linked to a coordinated regulation of fragile genes expression.

Also flagged:TOMM40RPEPPM1DZNF232TNRC9TM4SF11
Journal Article 2006-09-18 ✓ 5 Snippets Staub E, Gröne J, Mennerich D, Röpcke S, Klamann I, Hinzmann B, Castanos-Velez E, Mann B, Pilarsky C, Brümmendorf T, Weber B, Buhr HJ, Rosenthal A.
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ARFGEF2

DCC at 18q21.3 (OMIM 120470) // loss of 18q21.1 in CRC cell lines [25] // SMAD2 // SMAD4 mutations in CRC [71] // loss of expression and genomic DNA of 18 [17]

The DCC (deleted in colorectal carcinoma), proximal to MBD2, is the largest gene in this region, but no statements about its expression can be made because of a lack of informative expression measures.

…TheDCC(deleted in colorectal…

…deletions targeted atDCCdisruption.…

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<h4>Background</h4>Cancer development is accompanied by genetic phenomena like deletion and amplification of chromosome parts or alterations of chromatin structure. It is expected that these mechanisms have a strong effect on regional gene expression.<h4>Results</h4>We investigated genome-wide gene expression in colorectal carcinoma (CRC) and normal epithelial tissues from 25 patients using oligonucleotide arrays. This allowed us to identify 81 distinct chromosomal islands with aberrant gene expression. Of these, 38 islands show a gain in expression and 43 a loss of expression. In total, 7.892 genes (25.3% of all human genes) are located in aberrantly expressed islands. Many chromosomal regions that are linked to hereditary colorectal cancer show deregulated expression. Also, many known tumor genes localize to chromosomal islands of misregulated expression in CRC.<h4>Conclusion</h4>An extensive comparison with published CGH data suggests that chromosomal regions known for frequent deletions in colon cancer tend to show reduced expression. In contrast, regions that are often amplified in colorectal tumors exhibit heterogeneous expression patterns: even show a decrease of mRNA expression. Because for several islands of deregulated expression chromosomal aberrations have never been observed, we speculate that additional mechanisms (like abnormal states of regional chromatin) also have a substantial impact on the formation of co-expression islands in colorectal carcinoma.

Also flagged:transcription factorsgene expressiontranscription factorTFbindinggene expressions
Journal Article 2006-09-18 No Snippets Yu X, Lin J, Zack DJ, Qian J.
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Tissue-specific gene expression is generally regulated by more than a single transcription factor (TF). Multiple TFs work in concert to achieve tissue specificity. In order to explore these complex TF interaction networks, we performed a large-scale analysis of TF interactions for 30 human tissues. We first identified tissue-specific genes for 30 tissues based on gene expression databases. We then evaluated the relationships between TFs using the relative position and co-occurrence of their binding sites in the promoters of tissue-specific genes. The predicted TF-TF interactions were validated by both known protein-protein interactions and co-expression of their target genes. We found that our predictions are enriched in known protein-protein interactions (>80 times that of random expectation). In addition, we found that the target genes show the highest co-expression in the tissue of interest. Our findings demonstrate that non-tissue specific TFs play a large role in regulation of tissue-specific genes. Furthermore, they show that individual TFs can contribute to tissue specificity in different tissues by interacting with distinct TF partners. Lastly, we identified several tissue-specific TF clusters that may play important roles in tissue-specific gene regulation.

Also flagged:C1 inhibitorC1-InhangioedemaC1NHC1C1r
Journal Article 2006-09-18 ✓ 1 Snippet Blanch A, Roche O, Urrutia I, Gamboa P, Fontán G, López-Trascasa M.
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…<h4>Background</h4>C1 InhibitorInhibitor (C1-Inh) deficiency…

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<h4>Background</h4>C1 Inhibitor (C1-Inh) deficiency causes angioedema and can be hereditary (HAE), caused by mutations in the C1-Inh gene (C1NH), or acquired (AAE). Patients with HAE show a complement profile different from that of patients with AAE with normal levels of C1 (C1q, C1r, and C1s).<h4>Objective</h4>We sought to characterize the complement profile of a patient with HAE and a mutation in homozygosis in the C1NH gene (c.1576T>G, Ile462Ser) and study his family.<h4>Methods</h4>Biochemical diagnosis of HAE was confirmed by analyzing the C1NH gene. Further studies on the levels and activation states of the C1q, C1r, C1s, and C1-Inh components of the classical pathway of complement activation were also performed.<h4>Results</h4>Another 7 members of the family were given diagnoses of HAE: 1 was homozygous and 6 were heterozygous for the C1NH mutation c.1576T>G. The homozygous patients showed undetectable C1q levels, reduced C1s levels, the circulating active form of C1r, and a C1-Inh mostly in its cleaved inactive form in plasma.<h4>Conclusion</h4>This is the first report of patients homozygous for a mutation affecting the coding region of C1NH. These patients showed a unique activation and consumption profile of the classical complement activation pathway different from that commonly observed in patients with HAE but similar to that of patients with AAE.<h4>Clinical implications</h4>The most common HAE treatment is attenuated androgens, which increase the C1NH gene transcription levels. Because the homozygous patients lack a wild-type allele, long-term prophylactic treatment with attenuated androgens might not be advisable.

Also flagged:chaperoninpolyglutamineneurodegenerative disordersHuntington's diseaseKennedy's diseaseataxias
Journal Article 2006-09-17 ✓ 5 Snippets Kitamura A, Kubota H, Pack CG, Matsumoto G, Hirayama S, Takahashi Y, Kimura H, Kinjo M, Morimoto RI, Nagata K.
In-Text Gene Mentions

…cytotoxicity of huntingtin (Htt)-polyQ proteins in mammalian…

…Ai-mediated knockdown enhancedHtt-polyQ aggregate formation and…

…states of theHtt-polyQ proteins by fluorescenc…

…appearance of solubleHtt-polyQ aggregates.…

…of CCT suppressedHttaggregation and neuronal…

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Polyglutamine (polyQ)-expansion proteins cause neurodegenerative disorders including Huntington's disease, Kennedy's disease and various ataxias. The cytotoxicity of these proteins is associated with the formation of aggregates or other conformationally toxic species. Here, we show that the cytosolic chaperonin CCT (also known as TRiC) can alter the course of aggregation and cytotoxicity of huntingtin (Htt)-polyQ proteins in mammalian cells. Disruption of the CCT complex by RNAi-mediated knockdown enhanced Htt-polyQ aggregate formation and cellular toxicity. Analysis of the aggregation states of the Htt-polyQ proteins by fluorescence correlation spectroscopy revealed that CCT depletion results in the appearance of soluble Htt-polyQ aggregates. Similarly, overexpression of all eight subunits of CCT suppressed Htt aggregation and neuronal cell death. These results indicate that CCT has an essential role in protecting against the cytotoxicity of polyQ proteins by affecting the course of aggregation.

Also flagged:chaperoninpolyglutamineCCTCCT1bindingneurodegenerative disease
Journal Article 2006-09-17 ✓ 5 Snippets Tam S, Geller R, Spiess C, Frydman J.
In-Text Gene Mentions

…variants of huntingtin (Htt) and effectively inhibits…

…sufficient to remodelHtt-aggregate morphology in vivo…

…early role preventingHttaccess to pathogenic…

…, and reducesHtt-induced toxicity in neuronal…

…specificity of theHtt–CCT1 interaction, the CCT1…

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Misfolding and aggregation of proteins containing expanded polyglutamine repeats underlie Huntington's disease and other neurodegenerative disorders. Here, we show that the hetero-oligomeric chaperonin TRiC (also known as CCT) physically interacts with polyglutamine-expanded variants of huntingtin (Htt) and effectively inhibits their aggregation. Depletion of TRiC enhances polyglutamine aggregation in yeast and mammalian cells. Conversely, overexpression of a single TRiC subunit, CCT1, is sufficient to remodel Htt-aggregate morphology in vivo and in vitro, and reduces Htt-induced toxicity in neuronal cells. Because TRiC acts during de novo protein biogenesis, this chaperonin may have an early role preventing Htt access to pathogenic conformations. Based on the specificity of the Htt-CCT1 interaction, the CCT1 substrate-binding domain may provide a versatile scaffold for therapeutic inhibitors of neurodegenerative disease.

Also flagged:growth conesNetrin-1localizationβ-actinprotein synthesisretinal growth cones
Journal Article 2006-09-17 ✓ 1 Snippet Leung KM, van Horck FP, Lin AC, Allison R, Standart N, Holt CE.
In-Text Gene Mentions

DCC

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Local protein synthesis regulates the turning of growth cones to guidance cues, yet little is known about which proteins are synthesized or how they contribute to directional steering. Here we show that beta-actin mRNA resides in Xenopus laevis retinal growth cones where it binds to the RNA-binding protein Vg1RBP. Netrin-1 induces the movement of Vg1RBP granules into filopodia, suggesting that it may direct the localization and translation of mRNAs in growth cones. Indeed, a gradient of netrin-1 activates a translation initiation regulator, eIF-4E-binding protein 1 (4EBP), asymmetrically and triggers a polarized increase in beta-actin translation on the near side of the growth cone before growth cone turning. Inhibition of beta-actin translation abolishes both the asymmetric rise in beta-actin and attractive, but not repulsive, turning. Our data suggest that newly synthesized beta-actin, concentrated near sites of signal reception, provides the directional bias for polymerizing actin in the direction of an attractive stimulus.

Also flagged:Hdhp53Huntingtintumor suppressor p53HDpathogenesis
Journal Article 2006-09-15 ✓ 1 Snippet Ryan AB, Zeitlin SO, Scrable H.
In-Text Gene Mentions

htt

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Huntingtin, the protein product of the Huntington's disease (HD) gene, is known to interact with the tumor suppressor p53. It has recently been shown that activation of p53 upregulates the level of huntingtin, both in vitro and in vivo, whereas p53 deficiency in HD-transgenic flies and mice has been found to be beneficial. To explore further the involvement of p53 in HD pathogenesis, we generated mice homozygous for a mutant allele of Hdh (HdhQ140) and with zero, one, or two functional alleles of p53. p53 deficiency resulted in a reduction of mutant huntingtin expression in brain and testis, an increase in proenkephalin mRNA expression and a significant increase in nuclear aggregate formation in the striatum. Because aggregation of mutant huntingtin is suggested to be a protective mechanism, both the increase in aggregate load and the restoration of proenkephalin expression suggest a functional rescue of at least several aspects of the HD phenotype by a deficiency in p53.

Also flagged:polyglutaminepeptidesHuntington's diseaseHDpeptidenucleus
Journal Article 2006-09-15 ✓ 4 Snippets Slepko N, Bhattacharyya AM, Jackson GR, Steffan JS, Marsh JL, Thompson LM, Wetzel R.
In-Text Gene Mentions

Htt exon 1 protein with an Q(93) repeat accelerates both aggregate formation and neurotoxicity

…of HD expressingHttexon 1 protein…

Htt S830

Htt

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The dependence of disease risk and age-of-onset on expanded CAG repeat length in diseases like Huntington's disease (HD) is well established and correlates with the repeat-length-dependent nucleation kinetics of polyglutamine (polyGln) aggregation. The wide variation in ages of onset among patients with the same repeat length, however, suggests a role for modifying factors. Here we describe the ability of normal-length polyGln repeat sequences to greatly accelerate the nucleation kinetics of an expanded polyGln peptide. We find that normal-length polyGln peptides enhance the in vitro nucleation kinetics of a Q(47) peptide in a concentration-dependent and repeat-length-dependent manner. In vivo, we show that coexpression of a Q(20) sequence in a Drosophila model of HD expressing Htt exon 1 protein with an Q(93) repeat accelerates both aggregate formation and neurotoxicity. The accelerating effect of short polyGln peptides is attributable to the promiscuity of polyGln aggregate elongation and reflects the intimate relationship between nucleus formation and early elongation events in establishing nucleation kinetics. The results suggest that the overall state of the polyGln protein network in a cellular environment may have a profound effect on the toxic consequences of polyGln expansion and thus may serve as a genetic modifier of age of onset in HD.

Also flagged:Butyrategene expressionsodiumoligonucleotideoligonucleotidescell cycle
Journal Article 2006-09-14 No Snippets Li RW, Li C.
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<h4>Background</h4>Global gene expression profiles of bovine kidney epithelial cells regulated by sodium butyrate were investigated with high-density oligonucleotide microarrays. The bovine microarray with 86,191 distinct 60mer oligonucleotides, each with 4 replicates, was designed and produced with Maskless Array Synthesizer technology. These oligonucleotides represent approximately 45,383 unique cattle sequences.<h4>Results</h4>450 genes significantly regulated by butyrate with a median False Discovery Rate (FDR) = 0 % were identified. The majority of these genes were repressed by butyrate and associated with cell cycle control. The expression levels of 30 selected genes identified by the microarray were confirmed using real-time PCR. The results from real-time PCR positively correlated (R = 0.867) with the results from the microarray.<h4>Conclusion</h4>This study presented the genes related to multiple signal pathways such as cell cycle control and apoptosis. The profound changes in gene expression elucidate the molecular basis for the pleiotropic effects of butyrate on biological processes. These findings enable better recognition of the full range of beneficial roles butyrate may play during cattle energy metabolism, cell growth and proliferation, and possibly in fighting gastrointestinal pathogens.

Also flagged:prolineHuntingtinneurodegenerative diseasesHuntingtonHsp104chaperones
Journal Article 2006-09-14 No Snippets Dehay B, Bertolotti A.
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Nine neurodegenerative diseases, such as Huntington, are caused by a polyglutamine (poly(Q)) expansion in otherwise unrelated proteins. Although poly(Q) expansion causes aggregation of the affected proteins, the protein context might determine the selective neuronal vulnerability found in each disease. Here we have report that, although expression of Huntingtin derivatives with a pathological poly(Q) expansion are innocuous in yeast, deletion of the flanking proline-rich region alters the shape and number of poly(Q) inclusions and unmasks toxic properties. Strikingly, deletion of Hsp104 increases the size of inclusions formed by expanded poly(Q) lacking the proline-rich region and abolishes toxicity. Overexpression of the chaperones Hsp104 or Hsp70 rescues growth defects in affected cells without resolving inclusions. However, aggregates formed by nontoxic Huntingtin derivatives or by toxic derivatives cured by chaperones are physically distinct from aggregates formed by toxic proteins. This study identifies the proline-rich region in Huntingtin as a profound cis-acting modulator of expanded poly(Q) toxicity and distinguishes between aggregates of toxic or non-toxic proteins.

Also flagged:tamoxifenbreast cancerestrogenestradiolestrogen receptorbinding
Journal Article 2006-09-13 ✓ 1 Snippet Kim NN, Stankovic M, Armagan A, Cushman TT, Goldstein I, Traish AM.
In-Text Gene Mentions

…aliquots of theDCC-treated vaginal tissue extrac…

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<h4>Background</h4>Tamoxifen, a selective estrogen receptor modulator with both estrogenic and anti-estrogenic activity, is widely used as adjuvant therapy in breast cancer patients. Treatment with tamoxifen is associated with sexual side effects, such as increased vaginal dryness and pain/discomfort during sexual activity. There have been limited investigations of the effect of tamoxifen on estrogen-dependent peripheral genital arousal responses. The objective of this study was to investigate the effects of tamoxifen on vaginal physiology in the rat.<h4>Methods</h4>Female Sprague-Dawley rats were subjected to sham surgery or bilateral ovariectomy. After 2 weeks, sham-operated rats were implanted with subcutaneous osmotic infusion pumps containing vehicle (control) or tamoxifen (150 microg/day). Ovariectomized rats were similarly infused with vehicle. After an additional 2 weeks, vaginal blood flow responses to pelvic nerve stimulation were measured by laser Doppler flowmetry and vaginal tissue was collected for histological and biochemical assay.<h4>Results</h4>Tamoxifen treatment did not change plasma estradiol concentrations relative to control animals, while ovariectomized rats exhibited a 60% decrease in plasma estradiol. Tamoxifen treatment caused a significant decrease in mean uterine weight, but did not alter mean vaginal weight. Vaginal blood flow was significantly decreased in tamoxifen-infused rats compared to controls. Similar to ovariectomized animals, estrogen receptor binding was increased and arginase enzyme activity was decreased in tamoxifen-infused rats. However, different from control and ovariectomized animals, the vaginal epithelium in tamoxifen-infused rats appeared highly mucified. Periodic acid-Schiff staining confirmed a greater production of carbohydrate-rich compounds (e.g. mucin, glycogen) by the vaginal epithelium of tamoxifen-infused rats.<h4>Conclusion</h4>The observations suggest that tamoxifen exerts both anti-estrogenic and pro-estrogenic effects in the vagina. These physiological alterations may eventually lead to vaginal atrophy and compromise sexual function.

Also flagged:tumor suppressor proteinovarian cancerbeta-cateninepithelial ovarian cancerdeleted in colorectaltumor
Journal Article 2006-09-13 ✓ 5 Snippets Bamias A, Yu Z, Weinberger PM, Markakis S, Kowalski D, Camp RL, Rimm DL, Dimopoulos MA, Psyrri A.
In-Text Gene Mentions

Patients with low nuclear DCC expression had a 3-year progression-free survival (PFS) rate of 0% compared with 33% of those with high DCC expression (P = 0.0067).

Here, we sought to determine the association of DCC with beta-catenin protein levels, clinicopathological parameters and patient outcome in ovarian cancer using a method of in situ compartmentalized protein analysis.<h4>Methods</h4>A tissue array composed of 150 advanced-stage ovarian cancers, treated with surgical debulking and platinum-paclitaxel (Taxol) combination chemotherapy, was constructed.

Between DCC and beta-catenin, a significant relationship was found, where tumors with low DCC had low beta-catenin and vice versa (P = 0.003).<h4>Conclusions</h4>Low nuclear DCC levels predict for poor patient outcome in epithelial ovarian cancer.

<h4>Background</h4>The deleted in colorectal cancer (DCC) protein, the product of DCC tumor suppressor gene, is frequently altered in cancer.

…quantitative analysis ofDCCtumor suppressor protein…

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<h4>Background</h4>The deleted in colorectal cancer (DCC) protein, the product of DCC tumor suppressor gene, is frequently altered in cancer. Preclinical data demonstrate that DCC regulates beta-catenin levels. Here, we sought to determine the association of DCC with beta-catenin protein levels, clinicopathological parameters and patient outcome in ovarian cancer using a method of in situ compartmentalized protein analysis.<h4>Methods</h4>A tissue array composed of 150 advanced-stage ovarian cancers, treated with surgical debulking and platinum-paclitaxel (Taxol) combination chemotherapy, was constructed. For evaluation of protein expression, we used an immunofluorescence-based method of automated in situ quantitative measurement of protein analysis (AQUA).<h4>Results</h4>One hundred and twelve patients (74%) had sufficient tissue for AQUA. The median follow-up time for the entire cohort was 33 months. Patients with low nuclear DCC expression had a 3-year progression-free survival (PFS) rate of 0% compared with 33% of those with high DCC expression (P = 0.0067). In multivariate analysis, low nuclear DCC expression level retained its prognostic significance for PFS. Between DCC and beta-catenin, a significant relationship was found, where tumors with low DCC had low beta-catenin and vice versa (P = 0.003).<h4>Conclusions</h4>Low nuclear DCC levels predict for poor patient outcome in epithelial ovarian cancer. DCC may exert its antitumor function, in part, through regulation of beta-catenin levels.

Also flagged:mitochondrialcalciumHuntington diseaseHDCa2+mitochondria
Journal Article 2006-09-13 No Snippets Milakovic T, Quintanilla RA, Johnson GV.
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Huntington disease (HD) is caused by a pathological elongation of CAG repeats in the huntingtin protein gene and is characterized by atrophy and neuronal loss primarily in the striatum. Mitochondrial dysfunction and impaired Ca2+ homeostasis in HD have been suggested previously. Here, we elucidate the effects of Ca2+ on mitochondria from the wild type (STHdhQ7/Q7) and mutant (STHdhQ111/Q111) huntingtin-expressing cells of striatal origin. When treated with increasing Ca2+ concentrations, mitochondria from mutant huntingtin-expressing cells showed enhanced sensitivity to Ca2+, as they were more sensitive to Ca2+-induced decreases in state 3 respiration and DeltaPsim, than mitochondria from wild type cells. Further, mutant huntingtin-expressing cells had a reduced mitochondrial Ca2+ uptake capacity in comparison with wild type cells. Decreases in state 3 respiration were associated with increased mitochondrial membrane permeability. The DeltaPsim defect was attenuated in the presence of ADP and the decreases in Ca2+ uptake capacity were abolished in the presence of Permeability Transition Pore (PTP) inhibitors. These findings clearly indicate that mutant huntingtin-expressing cells have mitochondrial Ca2+ handling defects that result in respiratory deficits and that the increased sensitivity to Ca2+ induced mitochondrial permeabilization maybe a contributing mechanism to the mitochondrial dysfunction in HD.

Also flagged:mitochondrialOXPHOS complexes IIHuntington's diseaseHDpolyglutaminegreen fluorescent protein
Journal Article 2006-09-12 ✓ 1 Snippet Solans A, Zambrano A, Rodríguez M, Barrientos A.
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We have constructed a stable inducible yeast model of HD by expressing a human huntingtin fragment containing a mutant polyglutamine tract of 103Q fused to green fluorescent protein (GFP), and a control expressing a wild-type 25Q domain fused to GFP in a wild-type strain.

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Mitochondrial dysfunction may play an important role in the pathogenic mechanism of Huntington's disease (HD). However, the exact mechanism by which mutated huntingtin could cause bioenergetic dysfunction is still unknown. We have constructed a stable inducible yeast model of HD by expressing a human huntingtin fragment containing a mutant polyglutamine tract of 103Q fused to green fluorescent protein (GFP), and a control expressing a wild-type 25Q domain fused to GFP in a wild-type strain. We showed that in yeast cells expressing 103Q, cell respiration was progressively reduced after 4-6 h of induction with galactose, down to 50% of the control after 10 h of induction. The cell respiration defect results from an alteration in the function and amount of mitochondrial respiratory chain complex II+III, in congruency to data obtained from postmortem brain of HD patients and from toxin models. In our model, the production of reactive oxygen species (ROS) is significantly enhanced in cells expressing 103Q. Quenching of ROS with resveratrol partially prevents the cell respiration defect. Mitochondrial morphology and distribution were also altered in cells expressing 103Q, probably resulting from the interaction of aggregates with portions of the mitochondrial web and from a progressive disruption of the actin cytoskeleton. We propose a mechanism for mitochondrial dysfunction in our yeast model of HD in which the interactions of misfolded/aggregated polyglutamine domains with the mitochondrial and actin networks lead to disturbances in mitochondrial distribution and function and to increase in ROS production. Oxidative damage could preferentially affect the stability and function of enzymes containing iron-sulfur clusters such as complexes II and III. Our yeast model represents a very useful paradigm to study mitochondrial physiology alterations in the pathogenic mechanism of HD.

Also flagged:serotonin transporterdeathpsychiatric disorderpathogenesis
Journal Article 2006-09-12 ✓ 3 Snippets Li D, He L.
In-Text Gene Mentions

…etween serotonin transporter (5-HTT) and suicidal behavior.…

…the serotonin transporter (5-HTT) gene and suicidal…

…of the brain5-HTTin the pathogenesis…

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Suicidal behavior, which ranks among the top 10 causes of death worldwide, is an important public-health problem and a psychiatric disorder, which has been the subject of considerable study. Studies have shown association between the serotonin transporter (5-HTT) gene and suicidal behavior, although a proportion of alternative studies have produced contrary results both in terms of positive and negative findings, possibly reflecting inadequate statistical power and the use of different populations. Using the cumulative data from recent years in both European and, more particularly, Asian populations, this updated meta-analysis seeks to examine whether the aggregate data provide evidence of statistical significance, and to clarify the contradictory findings suggested by previous studies. It covers all published studies using multiple research methods up to January 2006. Compared with a previous meta-analysis, which found no association between the 5-HTTLPR polymorphism and suicidal behavior (P=0.38), the current results (39 studies) suggest a significant association with a P-value of 0.0068 (overall odds ratio=0.88 (0.8,0.97)), and supports the involvement of the brain 5-HTT in the pathogenesis of suicidal behavior.

Also flagged:ironintercellular adhesion molecule-1lipoproteincardiovascular diseasesICAM-1binding
Journal Article 2006-09-11 ✓ 1 Snippet van Tits LJ, Jacobs EM, Swinkels DW, Lemmers HL, van der Vleuten GM, de Graaf J, Stalenhoef AF.
In-Text Gene Mentions

…outpatient clinic forhemochromatosisfamily screening.<h4>Results</…

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<h4>Background</h4>Excess body iron is associated with increased cardiovascular disease risk, possibly via non-transferrin-bound iron (NTBI)-mediated enhancement of inflammation and oxidation of low-density lipoprotein (LDL).<h4>Methods</h4>We assessed this proposed atherosclerotic mechanism of body iron by determining the relationship of levels of serum iron parameters, including NTBI, with plasma markers of inflammation and LDL oxidation in 232 subjects who visited the outpatient clinic for hemochromatosis family screening.<h4>Results</h4>Plasma level of soluble intercellular adhesion molecule-1 (sICAM-1) was positively related to ferritin (standardized beta coefficient 0.16) and to NTBI (0.185) and negatively to total iron-binding capacity (TIBC, -0.166). Significant higher levels of sICAM-1 were found for subjects in the highest quartile of NTBI compared to the lowest quartile of NTBI (122 microg/L (107-141) and 106 microg/L (89-125), median (interquartile range), p<0.001). Odds ratio of subjects having sICAM-1 level above 134 microg/L (75th percentile) in the highest and lowest quartile of NTBI amounted 2.3. White blood cell count was positively related to ferritin (0.149). High-sensitivity C-reactive protein, interleukin-6, interleukin-8, oxidized LDL, oxidized LDL/apolipoprotein B and IgG and IgM antibodies to oxidized LDL were not related to any of the markers of iron status.<h4>Conclusion</h4>Excess body iron, reflected by elevated serum ferritin and NTBI and decreased TIBC, is associated with increased plasma level of sICAM-1 but not with markers of in vivo LDL oxidation.

Also flagged:Ca(v)2.3 voltage-gated calcium channelCa2+voltage-gated calcium channelspathogenesisepilepsyepileptic syndromes
Journal Article 2006-09-11 No Snippets Weiergräber M, Kamp MA, Radhakrishnan K, Hescheler J, Schneider T.
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The Ca(v)2.3 encoded Ca2+ channel is probably one of the least well-understood voltage-gated calcium channels in terms of physiology, pharmacology and clinical relevance. Here we provide a detailed insight into the functional involvement of Ca(v)2.3 in etiology and pathogenesis of both convulsive and non-convulsive seizures. In the CNS, Ca(v)2.3 containing E/R-type Ca2+ channels are involved in triggering epileptiform discharges by significantly contributing to plateau potentials and afterdepolarisations. Pharmacological analysis further revealed that various antiepileptic drugs specifically target Ca(v)2.3 VGCCs capable of blocking epileptiform burst activity. Whereas electroencephalographic recordings in Ca(v)2.3-/- mice did not reveal any ictal-like discharges, seizure susceptibility was dramatically reduced in Ca(v)2.3-/- animals compared to controls, further supporting the observation that Ca(v)2.3 is an important factor in triggering epileptiform activity in neuronal populations. Although some aspects of its relationship to epilepsy have been uncovered, further functional characterization of Ca(v)2.3 in etiology and pathogenesis of human epileptic syndromes as well as development of new antiepileptic drugs specifically targeting Ca(v)2.3 turns out to become indispensable.

Also flagged:histone H1protamine-likechromatinorganizationProtamine-like proteinsnuclear basic proteins
Journal Article 2006-09-11 ✓ 1 Snippet Saperas N, Chiva M, Casas MT, Campos JL, Eirín-López JM, Frehlick LJ, Prieto C, Subirana JA, Ausió J.
In-Text Gene Mentions

…related to somaticlinker histoneshistones (histone H1…

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Protamine-like proteins constitute a group of sperm nuclear basic proteins that have been shown to be related to somatic linker histones (histone H1 family). Like protamines, they usually replace the chromatin somatic histone complement during spermiogenesis; hence their name. Several of these proteins have been characterized to date in invertebrate organisms, but information about their occurrence and characterization in vertebrates is still lacking. In this sense, the genus Mullus is unique, as it is the only known vertebrate that has its sperm chromatin organized by virtually only protamine-like proteins. We show that the sperm chromatin of this organism is organized by two type I protamine-like proteins (PL-I), and we characterize the major protamine-like component of the fish Mullus surmuletus (striped red mullet). The native chromatin structure resulting from the association of these proteins with DNA was studied by micrococcal nuclease digestion as well as electron microscopy and X-ray diffraction. It is shown that the PL-I proteins organize chromatin in parallel DNA bundles of different thickness in a quite distinct arrangement that is reminiscent of the chromatin organization of those organisms that contain protamines (but not histones) in their sperm.

Also flagged:thrombotic endocarditisnonbacterialadenocarcinomasovarian clear cell adenocarcinomainfective endocarditisneoplasm
Journal Article 2006-09-11 ✓ 1 Snippet Aryana A, Esterbrooks DJ, Morris PC.
In-Text Gene Mentions

Antithrombin-III

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We describe the case of a 43-year-old woman with transient ischemic neurologic deficits and recurrent systemic and pulmonary emboli in whom infectious work-up and extensive thrombophilic evaluation were unremarkable. Transesophageal echocardiography (TEE) established the diagnosis of nonbacterial thrombotic endocarditis (NBTE). This is a rare condition often associated with hypercoagulable states or advanced malignancy such as adenocarcinomas, characterized by cardiac vegetations along valvular coaptation lines without destruction of leaflets. In our patient, we diagnosed an ovarian clear cell adenocarcinoma, a malignant disorder that has been rarely reported in association with NBTE. This case illustrates that NBTE can present as an atypical manifestation of malignancy and must be distinguished from infective endocarditis, which implies a different therapeutic strategy. When confronted with findings of NBTE without a clear etiology, an occult neoplasm must be excluded. Anticoagulant therapy is the mainstay of treatment. However, cardiac vegetations may require surgical intervention in rare instances.

Also flagged:caspase-9tumor necrosis factorTNFcaspase-8membranedeath
Journal Article 2006-09-11 ✓ 1 Snippet Gyrd-Hansen M, Farkas T, Fehrenbacher N, Bastholm L, Høyer-Hansen M, Elling F, Wallach D, Flavell R, Kroemer G, Nylandsted J, Jäättelä M.
In-Text Gene Mentions

DCC

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The apoptosome, a heptameric complex of Apaf-1, cytochrome c, and caspase-9, has been considered indispensable for the activation of caspase-9 during apoptosis. By using a large panel of genetically modified murine embryonic fibroblasts, we show here that, in response to tumor necrosis factor (TNF), caspase-8 cleaves and activates caspase-9 in an apoptosome-independent manner. Interestingly, caspase-8-cleaved caspase-9 induced lysosomal membrane permeabilization but failed to activate the effector caspases whereas apoptosome-dependent activation of caspase-9 could trigger both events. Consistent with the ability of TNF to activate the intrinsic apoptosis pathway and the caspase-9-dependent lysosomal cell death pathway in parallel, their individual inhibition conferred only a modest delay in TNF-induced cell death whereas simultaneous inhibition of both pathways was required to achieve protection comparable to that observed in caspase-9-deficient cells. Taken together, the findings indicate that caspase-9 plays a dual role in cell death signaling, as an activator of effector caspases and lysosomal membrane permeabilization.

Also flagged:adenylyl cyclasenetrin-1conesaxonsaxongrowth cones
Journal Article 2006-09-10 ✓ 1 Snippet Wu KY, Zippin JH, Huron DR, Kamenetsky M, Hengst U, Buck J, Levin LR, Jaffrey SR.
In-Text Gene Mentions

DCC

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Growth cones at the tips of nascent and regenerating axons direct axon elongation. Netrin-1, a secreted molecule that promotes axon outgrowth and regulates axon pathfinding, elevates cyclic AMP (cAMP) levels in growth cones and regulates growth cone morphology and axonal outgrowth. These morphological effects depend on the intracellular levels of cAMP. However, the specific pathways that regulate cAMP levels in response to netrin-1 signaling are unclear. Here we show that 'soluble' adenylyl cyclase (sAC), an atypical calcium-regulated cAMP-generating enzyme previously implicated in sperm maturation, is expressed in developing rat axons and generates cAMP in response to netrin-1. Overexpression of sAC results in axonal outgrowth and growth cone elaboration, whereas inhibition of sAC blocks netrin-1-induced axon outgrowth and growth cone elaboration. Taken together, these results indicate that netrin-1 signals through sAC-generated cAMP, and identify a fundamental role for sAC in axonal development.

Also flagged:Hippiadapter proteinglutamineHuntington diseasedeathShh
Journal Article 2006-09-09 ✓ 2 Snippets Houde C, Dickinson RJ, Houtzager VM, Cullum R, Montpetit R, Metzler M, Simpson EM, Roy S, Hayden MR, Hoodless PA, Nicholson DW.
In-Text Gene Mentions

htt

htt-interacting protein-1

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Hippi functions as an adapter protein that mediates pro-apoptotic signaling from poly-glutamine-expanded huntingtin, an established cause of Huntington disease, to the extrinsic cell death pathway. To explore other functions of Hippi we generated Hippi knock-out mice. This deletion causes randomization of the embryo turning process and heart looping, which are hallmarks of defective left-right (LR) axis patterning. We report that motile monocilia normally present at the surface of the embryonic node, and proposed to initiate the break in LR symmetry, are absent on Hippi-/- embryos. Furthermore, defects in central nervous system development are observed. The Sonic hedgehog (Shh) pathway is downregulated in the neural tube in the absence of Hippi, which results in failure to establish ventral neural cell fate. Together, these findings demonstrate a dual role for Hippi in cilia assembly and Shh signaling during development, in addition to its proposed role in apoptosis signal transduction in the adult brain under pathogenically stressful conditions.

Also flagged:nucleoluslocalizationNOP132DDX47nucleolar proteinsmall GTP binding protein
Journal Article 2006-09-08 No Snippets Sekiguchi T, Hayano T, Yanagida M, Takahashi N, Nishimoto T.
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Previously, we described a novel nucleolar protein, NOP132, which interacts with the small GTP binding protein RRAG A. To elucidate the function of NOP132 in the nucleolus, we identified proteins that interact with NOP132 using mass spectrometric methods. NOP132 associated mainly with proteins involved in ribosome biogenesis and RNA metabolism, including the DEAD-box RNA helicase protein, DDX47, whose yeast homolog is Rrp3, which has roles in pre-rRNA processing. Immunoprecipitation of FLAG-tagged DDX47 co-precipitated rRNA precursors, as well as a number of proteins that are probably involved in ribosome biogenesis, implying that DDX47 plays a role in pre-rRNA processing. Introduction of NOP132 small interfering RNAs induced a ring-like localization of DDX47 in the nucleolus, suggesting that NOP132 is required for the appropriate localization of DDX47 within the nucleolus. We propose that NOP132 functions in the recruitment of pre-rRNA processing proteins, including DDX47, to the region where rRNA is transcribed within the nucleolus.

Also flagged:congenital muscular dystrophyglycosyltransferasesdystrophinα-dystroglycanreticular nucleusaging
Journal Article 2006-09-07 ✓ 1 Snippet Litwack ED, Lee Y, Mallott JM.
In-Text Gene Mentions

Dcc

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Several forms of congenital muscular dystrophy result from mutations in glycosyltransferases that modify alpha-dystroglycan. As pontine hypoplasia has been reported in some clinical cases of congenital muscular dystrophy, we have begun to examine whether these glycosyltransferases are required for the normal development of the basilar pons, one of several precerebellar nuclei of the hindbrain. In veils (Large(vls)) mice, which carry a loss-of-function mutation in the Large glycosyltransferase gene, the basilar pons is absent. Instead, ectopic clusters of pontine neurons are found lateral to their normal site, suggesting that these neurons are unable to migrate to their appropriate site. Two other precerebellar nuclei, the lateral reticular nucleus and the inferior olive, are present in Large(vls) mice. In addition, the basilar pons forms normally in dystrophin-deficient mice. These results demonstrate that the Large glycosyltransferase but not dystrophin is required for normal basilar pontine development.

Also flagged:MemantinedeathHuntington's diseaseNMDA receptor-nitropropionic acidBcl-xl
Journal Article 2006-09-07 No Snippets Lee ST, Chu K, Park JE, Kang L, Ko SY, Jung KH, Kim M.
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Huntington's disease has an increase in the activated calpain, which is enhanced by the NMDA receptor activation. We investigated the neuroprotective effect of memantine in 3-nitropropionic acid (3NP)-induced striatal degeneration model. Either memantine (20 mg/kg/day) or PBS was intraperitoneally administered for five days with 3NP continuous infusion. In the memantine-treated group, the striatal lesion volume, the number of TUNEL+ cells, and Fluoro-Jade C+ degenerating neurons were all decreased. Memantine increased Bcl-xl and decreased Bax level. Memantine also exerted an inhibitory effect on the micro-calpain level and decreased the huntingtin proteolytic fragments. Those rats treated with memantine showed less degree of weight loss at 5 days. Subsequently, memantine was found to have neuroprotective effects and save striatal cells with decreasing calpain levels in the 3NP model of Huntington's disease.

Also flagged:deferipronedeferoxaminejuvenile hemochromatosisironmetabolismHeart failure
Journal Article 2006-09-07 ✓ 1 Snippet Fabio G, Minonzio F, Delbini P, Bianchi A, Cappellini MD.
In-Text Gene Mentions

…therapeutic approach inhemochromatosispatients but is…

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Juvenile hemochromatosis (JH) is a rare autosomal recessive disorder of iron metabolism, genetically heterogeneous. In JH, symptomatic organ involvement occurs as early as the second decade of life. Heart failure and/or arrhythmias are the most frequent causes of death. Phlebotomy is the safest, most effective, and most economic therapeutic approach in hemochromatosis patients but is not indicated during the treatment of severe congestive heart failure with unstable hemodynamic status. The treatment of iron overload in these prohibitive clinical situations has to be carried out using iron chelators. We report a case of heart failure in the setting of unrecognized juvenile hemochromatosis successfully treated by the simultaneous administration of deferoxamine and deferiprone. To our knowledge, this is the first patient affected by JH treated with combined chelation regimen.

Also flagged:RNA-Dependent RNA Polymerase 2RDR2dcl2RNA-dependent RNA polymerase - 2dcl1Inflorescence
Journal Article 2006-09-05 ✓ 1 Snippet Lu C, Kulkarni K, Souret FF, MuthuValliappan R, Tej SS, Poethig RS, Henderson IR, Jacobsen SE, Wang W, Green PJ, Meyers BC.
In-Text Gene Mentions

SU(VAR)3–9 like histone methyltransferase

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The Arabidopsis genome contains a highly complex and abundant population of small RNAs, and many of the endogenous siRNAs are dependent on RNA-Dependent RNA Polymerase 2 (RDR2) for their biogenesis. By analyzing an rdr2 loss-of-function mutant using two different parallel sequencing technologies, MPSS and 454, we characterized the complement of miRNAs expressed in Arabidopsis inflorescence to considerable depth. Nearly all known miRNAs were enriched in this mutant and we identified 13 new miRNAs, all of which were relatively low abundance and constitute new families. Trans-acting siRNAs (ta-siRNAs) were even more highly enriched. Computational and gel blot analyses suggested that the minimal number of miRNAs in Arabidopsis is approximately 155. The size profile of small RNAs in rdr2 reflected enrichment of 21-nt miRNAs and other classes of siRNAs like ta-siRNAs, and a significant reduction in 24-nt heterochromatic siRNAs. Other classes of small RNAs were found to be RDR2-independent, particularly those derived from long inverted repeats and a subset of tandem repeats. The small RNA populations in other Arabidopsis small RNA biogenesis mutants were also examined; a dcl2/3/4 triple mutant showed a similar pattern to rdr2, whereas dcl1-7 and rdr6 showed reductions in miRNAs and ta-siRNAs consistent with their activities in the biogenesis of these types of small RNAs. Deep sequencing of mutants provides a genetic approach for the dissection and characterization of diverse small RNA populations and the identification of low abundance miRNAs.

Also flagged:epithelial ovarian carcinomasepithelial neoplasmschromosomeovarian tumorschromosomescancer
Journal Article 2006-09-01 ✓ 1 Snippet Tuhkanen H, Anttila M, Kosma VM, Heinonen S, Juhola M, Helisalmi S, Kataja V, Mannermaa A.
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…Loss ofDCCwas related to…

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Stromal cells are an active and integral part of epithelial neoplasms. We have previously observed allelic imbalance on chromosome 3p21 in both stromal and epithelial cells of ovarian tumors. This study was designed to explore gene dosage alterations throughout human chromosomes from stromal and epithelial cells of epithelial ovarian carcinomas. Thirteen stromal and 24 epithelial samples, microdissected from epithelial ovarian carcinomas, were analyzed using multiplex ligation-dependent probe amplification technique. Analysis covered 110 cancer related genes. Frequent genetic alterations were detected both in the stroma and epithelium of ovarian carcinomas. The mean number of altered genes per tumor was 10.8 in stroma and 23.6 in epithelium. In the stroma, the mean number of gains was 6.6 and of losses 4.2 and in the epithelium 13.7 and 9.9. The high number of changes associated with advanced tumor stage (p = 0.035) and death due to ovarian cancer (p = 0.032). The most frequent alteration was the deletion of the deleted in colorectal carcinoma (DCC) on chromosome 18q21.3 in 62% of samples. Loss of DCC was related to endometrioid subtype (p = 0.033). Large chromosomal aberrations were detected on the basis of alterations in adjacent genes. Most importantly, 38 genes showed similar genetic alterations (gain-gain or loss-loss) in stromal and epithelial compartments of 11 tumor pairs. Thus, frequent genetic alterations in stromal cells of epithelial ovarian carcinomas resembled those of malignant epithelial cells and may indicate a common precursor cell type. Epithelial-mesenchymal transition may generate transformed cancer cells and modify the tumor microenvironment with distinct properties.

Also flagged:prostate cancerandrogenHSP60heatshock protein 60titin
Journal Article 2006-09-01 No Snippets Johansson B, Pourian MR, Chuan YC, Byman I, Bergh A, Pang ST, Norstedt G, Bergman T, Pousette A.
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<h4>Background</h4>Androgen-sensitive prostate cancer cell-line LNCaP-FGC and androgen-resistant line LNCaP-r constitute a model for development of androgen resistance in prostate cancer.<h4>Methods</h4>Proteins differently expressed in the two cell-lines were identified by two-dimensional (2-D) electrophoresis and mass spectrometry. HSP60, more abundant in LNCaP-r, was studied by RT-PCR and immunohistochemistry in specimens of human prostate cancer.<h4>Results</h4>HSP60 was upregulated in LNCaP-r, nm23 in LNCaP-FGC, and titin (two isoforms) in either LNCaP-r or LNCaP-FGC. In non-malignant prostate, HSP60-staining was in the glandular compartment, particularly basal epithelial cells. In prostate cancer, most epithelial cells showed moderate-strong staining without apparent correlation between staining intensity and Gleason grade.<h4>Conclusions</h4>The LNCaP-FGC/LNCaP-r model, characterized by 2-D electrophoresis, reveals distinct proteomic alterations. With HSP60, results from cell-lines correlated with clinical results, indicating that this model can be used for dissection of mechanisms involved in transformation to androgen resistance and assignment of protein markers in prostate cancer.

Also flagged:serotonin transporterbindingdimethylaminobenzylaminepsychiatric disorders
Journal Article 2006-09-01 ✓ 2 Snippets Lundberg J, Halldin C, Farde L.
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…the serotonin transporter (5-HTT) in man.…

…in measurements of5-HTTbinding in brain…

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[(11)C]MADAM, or [(11)C]N,N-dimethyl-2-(2-amino-4-methylphenyl thio)benzylamine, is a radioligand suitable for positron emission tomography (PET) studies of the serotonin transporter (5-HTT) in man. The purpose of this study was to examine the test-retest reproducibility using a design tailored for future applied studies. Nine healthy male subjects were examined with PET and [(11)C]MADAM under baseline conditions at two occasions 4-8 weeks apart. The subjects participated in a Phase 1 trial to which the present study was an addendum. Eight regions of interest were studied, including frontal cortex, hippocampal complex, and the raphe nuclei. All regions, but the raphe nuclei, were defined on MR-images to which the PET-images were coregistered using SPM2. Binding potentials were calculated using the simplified reference tissue model, with cerebellum as reference region. Test-retest data were calculated from the binding potentials, and included binding potential (BP) quotient, BP difference, and the intraclass correlation coefficient. The quotient was about one in all regions, and the mean difference varied between 0 and 11%. The intraclass correlation coefficient varied between 0.96 and 0.51 in the raphe nuclei and averaged bilateral regions. [(11)C]MADAM was shown to have good to excellent reliability in measurements of 5-HTT binding in brain regions of interest in research on psychiatric disorders.

Also flagged:CBPHuntington's diseaseneurodegenerative diseasepolyglutamineCREB binding proteinhistone
Journal Article 2006-09-01 ✓ 3 Snippets Jiang H, Poirier MA, Liang Y, Pei Z, Weiskittel CE, Smith WW, DeFranco DB, Ross CA.
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These data suggest that CBP dysfunction and altered gene transcription contribute to mutant htt-induced neurotoxicity.

…Transfection with ahttexon1 construct containing…

…contribute to mutanthtt-induced neurotoxicity.…

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Huntington's disease is a neurodegenerative disease caused by an expanded polyglutamine stretch within the huntingtin protein. Transfection of mutant huntingtin causes cell toxicity and depletion of CREB binding protein (CBP) or its recruitment into huntingtin aggregates. However, the role of CBP has been controversial and the relationship between polyglutamine-induced toxicity and CBP depletion has not been examined on an individual cell basis. Using a single-cell based assay, we found that, in HT22 cells or primary neurons transfected with mutant huntingtin, cell toxicity was accompanied by CBP depletion, rather than merely recruitment. Transfection with a htt exon1 construct containing uninterrupted polyglutamine or a polyglutamine region engineered to form a compact beta structure resulted in cell toxicity. CBP depletion was accompanied by histone hypo-acetylation. CBP overexpression rescued both acetylated histone levels and cell toxicity. These data suggest that CBP dysfunction and altered gene transcription contribute to mutant htt-induced neurotoxicity.

Also flagged:Id2Idbindingcell growthcancerE2F4
Journal Article 2006-09-01 No Snippets Rodríguez JL, Sandoval J, Serviddio G, Sastre J, Morante M, Perrelli MG, Martínez-Chantar ML, Viña J, Viña JR, Mato JM, Avila MA, Franco L, López-Rodas G, Torres L.
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The Id (inhibitor of DNA binding or inhibitor of differentiation) helix-loop-helix proteins are involved in the regulation of cell growth, differentiation and cancer. The fact that the molecular mechanisms of liver regeneration are not completely understood prompted us to study the fate of Id2 in proliferating liver. Id2 increases in liver regeneration after partial hepatectomy, following the early induction of its gene. Co-immunoprecipitation shows that Id2 forms a complex with E2F4, p130 and mSin3A in quiescent liver and all these components are present at the c-myc promoter as shown using ChIP (chromatin immunoprecipitation). Activation of c-myc during hepatocyte priming (G0-G1 transition) correlates with the dissociation of Id2 and HDAC (histone deacetylase), albeit p130 remains bound at least until 6 h. Moreover, as the G0-G1 transition progresses, Id2 and HDAC again bind the c-myc promoter concomitantly with the repression of this gene. The time course of c-myc binding to the Id2 promoter, as determined by ChIP assays is compatible with a role of the oncoprotein as a transcriptional inducer of Id2 in liver regeneration. Immunohistochemical analysis shows that Id2 also increases in proliferating hepatocytes after bile duct ligation. In this case, the pattern of Id2 presence in the c-myc promoter parallels that found in regenerating liver. Our results may suggest a control role for Id2 in hepatocyte priming, through a p130 dissociation-independent regulation of c-myc.

Also flagged:polypeptidesphingomyelinmembranelocalizationamino acidsamino-acid
Journal Article 2006-09-01 ✓ 1 Snippet Morgan CP, Allen-Baume V, Radulovic M, Li M, Skippen A, Cockcroft S.
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DCC

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Mammalian PITPbeta (phosphatidylinositol transfer protein beta) is a 272-amino-acid polypeptide capable of transferring PtdIns, PtdCho and SM (sphingomyelin) between membrane bilayers. It has been reported that Ser262 present in the C-terminus of PITPbeta is constitutively phosphorylated and determines Golgi localization. We provide evidence for the expression of an sp (splice) variant of PITPbeta (PITPbeta-sp2) where the C-terminal 15 amino acids of PITPbeta-sp1 are replaced by an alternative C-terminus of 16 amino acids. PITPbeta-sp1 is the product of the first 11 exons, whereas PITPbeta-sp2 is a product of the first 10 exons followed by the twelfth exon--exon 11 being 'skipped'. Both splice variants are capable of PtdIns and PtdCho transfer, with PITPbeta-sp2 being unable to transport SM. PITPbeta is ubiquitously expressed, with the highest amounts of PITPbeta found in HL60 cells and in rat liver; HL60 cells express only PITPbeta-sp1, whereas rat liver expresses both sp variants in similar amounts. In both cell types, PITPbeta-sp1 is constitutively phosphorylated and both the PtdIns and PtdCho forms of PITPbeta-sp1 are present. In contrast, PITPbeta-sp2 lacks the constitutively phosphorylated Ser262 (replaced with glutamine). Nonetheless, both PITPbeta variants localize to the Golgi and, moreover, dephosphorylation of Ser262 of PITPbeta-sp1 does not affect its Golgi localization. The presence of PITPbeta sp variants adds an extra level of proteome complexity and, in rat liver, the single gene for PITPbeta gives rise to seven distinct protein species that can be resolved on the basis of their charge differences.

Also flagged:genetic diseasesHereditary hemochromatosis
Journal Article 2006-09-01 ✓ 5 Snippets Hoppe C, Watson RM, Long CM, Lorey F, Robles L, Klitz W, Styles L, Vichinsky E.
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To determine race-specific frequencies of the HFE mutations, C282Y and H63D, the authors applied an automated, high-throughput genotyping method to dried blood spot samples from a representative population of California newborns.

Hereditary hemochromatosis may be a candidate for large-scale screening in populations with a high prevalence of the common HFE

…Prevalence ofHFEmutations in California…

…of the commonHFEmutations.…

…frequencies of theHFEmutations, C282Y and…

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Advances in molecular diagnostics have led to an increased interest in expanding population-based screening to include genetic diseases that occur outside the newborn period. Hereditary hemochromatosis may be a candidate for large-scale screening in populations with a high prevalence of the common HFE mutations. To determine race-specific frequencies of the HFE mutations, C282Y and H63D, the authors applied an automated, high-throughput genotyping method to dried blood spot samples from a representative population of California newborns. In this sample of 3989 newborns, C282Y and H63D allele frequencies were highest in white (C282Y: 5.5 +/- 0.5%; H63D: 13.4 +/- 0.76%) and Hispanic (C282Y: 1.8 +/- 0.29%; H63D: 11.9 +/- 0.72%) newborns, and lowest in black (C282Y: 1.3 +/- 0.25%; H63D: 3.0 +/- 0.38%) and Asian (C282Y 0.5 +/- 0.16%; H63D 2.9 +/- 0.37%) newborns. The estimated prevalence of C282Y homozygotes in this multiracial population is 1.4/1000. As additional genetic and environmental risk factors for HHC are identified, neonatal screening may become an acceptable strategy to follow susceptible individuals and prevent clinical disease.

Also flagged:serotonin transporterADHDattention-deficit hyperactivity disorderserotoninsynaptic cleft
Journal Article 2006-09-01 ✓ 1 Snippet Wigg KG, Takhar A, Ickowicz A, Tannock R, Kennedy JL, Pathare T, Malone M, Schachar R, Barr CL.
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…The serotonin transporter (HTT) regulates the availability…

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Evidence from both human and animal studies implicates the serotonergic system in the development of attention-deficit hyperactivity disorder (ADHD) including positive association studies for several key serotonergic genes. The serotonin transporter (HTT) regulates the availability of serotonin by reuptake of the neurotransmitter from the synaptic cleft. Several studies have reported an association of this gene to ADHD, specifically the long variant of a common insertion/deletion polymorphism located in the promoter of this gene that results in increased transcription and higher HTT expression. An additional study found no evidence for an association with this polymorphism. Recently, an A/G single nucleotide polymorphism (SNP) was found within the promoter polymorphism with functional studies indicating that the long variant containing the G allele at this site behaves like the short variant. This previously unidentified functional change may have confounded earlier association studies. We investigated the relationship of several variants to ADHD: the promoter polymorphisms, SNP in the 3' untranslated region (3'UTR) with a reported association to ADHD and a rare, non-synonymous coding SNP. These polymorphisms were genotyped in 209 ADHD families identified through an affected proband. We did not find evidence for an association of these polymorphisms, or haplotypes of these polymorphisms, to ADHD in this sample.

Also flagged:ironmetabolismTransferrin receptor-1TfR1FPNmembrane
Journal Article 2006-09-01 ✓ 1 Snippet Bastin J, Drakesmith H, Rees M, Sargent I, Townsend A.
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…the location ofHFEis controversial.…

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Two anatomical sites that are important in human iron metabolism are the liver and placenta. Liver macrophages recycle iron from erythrocytes, and the placenta transfers iron from the mother to the fetus. The cellular distribution of proteins involved in iron transport in these two sites was studied. Transferrin receptor-1 (TfR1) and Ferroportin (FPN) expression was found on the placental syncytiotrophoblast (STB) and were polarised such that TfR1 was on the apical maternal-facing membrane and FPN was on the basal fetal-facing membrane, consistent with unidirectional iron transport from mother to fetus. Ferritin was strongly expressed in the stroma, suggesting that fetal tissue can store and accumulate iron. HFE was on some parts of the basal STB and, where present, HFE clearly colocalised with FPN but not TfR1. In the stroma, both HFE and FPN were present on CD68+ Hofbauer macrophage cells. In liver, the location of HFE is controversial. Using four mouse monoclonals and two polyclonal sera we showed that the pattern of HFE expression mirrored the distribution of CD68+ macrophage Kupffer cells. FPN was also most strongly expressed by CD68+ Kupffer cells. These findings contribute to understanding how iron is transported and stored in the human placenta and liver.

Also flagged:Raf kinasehepatocellular carcinomaRasRafMEKERK
Journal Article 2006-09-01 No Snippets Schuierer MM, Bataille F, Weiss TS, Hellerbrand C, Bosserhoff AK.
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The Ras/Raf/MEK/ERK signalling cascade is frequently deregulated in tumourigenic diseases and known to be involved in proliferation and transformation of cells. Also in hepatocellular carcinoma (HCC) increased ERK levels are observed and known to correlate with tumour progression, but the underlying molecular mechanism are unknown. We analyzed expression of Raf-1 kinase inhibitory protein (RKIP) in HCC. Expression of RKIP mRNA and protein was downregulated in HCC cell lines and tissue as compared to primary human hepatocytes (PHH) or non-tumorous liver tissue, respectively. Transfection of an HCC cell line with an RKIP expression construct blocked the Raf kinase pathway resulting in decreased activity of ERK1/2 and AP-1. In contrast, downregulation of RKIP by transfection with an antisense RKIP construct led to increased ERK1/2 and AP-1 activity. Since HCC develop in the majority of cases in cirrhotic liver tissue and cirrhosis is the main risk factor for HCC development, we analyzed RKIP expression also in non-cancerous cirrhotic liver tissues by immunohistochemistry. In contrast to normal liver tissue, where the staining was equally distributed within the cytoplasm, hepatocytes in cirrhotic liver revealed an intense RKIP staining of the membrane. It can be speculated that this changed RKIP expression pattern parallels impaired protein function in PHH in cirrhotic livers that may predispose PHH to malignant transformation. In addition, our study demonstrates functional relevance of downregulation of RKIP in HCC that may play an important role in HCC development and progression.

Also flagged:CD4CD3gene expressionOX40TNFSF15TNF
Journal Article 2006-09-01 No Snippets Kim MY, Toellner KM, White A, McConnell FM, Gaspal FM, Parnell SM, Jenkinson E, Anderson G, Lane PJ.
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We report here the quantitative expression of a set of immunity-related genes, including TNF family members, chemokine receptors, and transcription factors, in a CD4+ CD3- accessory cell. By correlating gene expression between cell-sorted populations of defined phenotype, we show that the genetic fingerprint of these CD4+ CD3- cells is distinct from dendritic cells, plasmacytoid dendritic cells, T cells, B cells, and NK cells. In contrast, it is highly similar to CD4+ CD3- cells isolated from embryonic and neonatal tissues, with the exception that only adult populations express OX40L and CD30L. We have previously reported that IL-7 signals regulate CD30L expression. In the present study, we show that both neonatal and adult CD4+ CD3- cells express the TNF family member, death receptor 3 (TNFRSF25), and that addition of TL1A (TNFSF15), the ligand for death receptor 3, up-regulates OX40L on neonatal CD4+ CD3- cells. Finally, we demonstrate that this differentiation occurs in vivo: neonatal CD4+ CD3- cells up-regulate both CD30L and OX40L after adoptive transfer into an adult recipient.

Also flagged:congenital heart diseaseB-type natriuretic peptideBNPbehavioralchronic illnessesasthma
Journal Article 2006-09-01 No Snippets Sleeper LA, Anderson P, Hsu DT, Mahony L, McCrindle BW, Roth SJ, Saul JP, Williams RV, Geva T, Colan SD, Clark BJ, Pediatric Heart Network Investigators.
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<h4>Background</h4>Clinical trials in children with congenital heart disease are often limited by the absence of the following: (1) a primary outcome that can be observed in a reasonable period; (2) information regarding health-related quality of life; (3) knowledge of the correlation between health status and ventricular function and exercise performance; (4) a sufficient number of children at a single institution to provide adequate statistical power; and (5) procedural and management differences between and within institutions.<h4>Methods</h4>The NHLBI-funded Pediatric Heart Network designed a cross-sectional study of children aged 6 to 18 years, from 7 pediatric clinical centers, who had undergone a Fontan procedure as treatment for congenital heart disease. Health-related quality of life was measured by the Child Health Questionnaire and the Congenital Heart Adolescent and Teenager Questionnaire. Ventricular function was assessed by maximal exercise testing, echocardiography, cardiac magnetic resonance imaging, and B-type natriuretic peptide. The study was designed to detect a correlation of R > or = 0.30 between health status scores and measures of ventricular function and performance in a subcohort with all study measures completed.<h4>Results</h4>A total of 1078 children were screened by chart review; 644 (60%) were eligible. The consent rate was 85% and 546 children were enrolled. Acquisition of echocardiograms, B-type natriuretic peptide, and health status was > or = 94%; completion rates were lower for maximal exercise testing (76%) and cardiac magnetic resonance imaging (41%).<h4>Conclusions</h4>This large study provides unique information regarding the relationship between health status and clinical measures in post-Fontan patients that will facilitate the design of future randomized trials.

Also flagged:tumorscolorectal carcinomatumorKRASAdenomatous Polyposis ColiAPC
Journal Article 2006-09-01 ✓ 5 Snippets Zauber NP, Sabbath-Solitare M, Marotta S, Perera LP, Bishop DT.
In-Text Gene Mentions

We evaluated 3 samples from each of 67 patients for point mutations in the KRAS gene, loss of heterozygosity (LOH) at the Adenomatous Polyposis Coli (APC) and Deleted in Colon Cancer (DCC) genes and for microsatellite instability (MSI) using polymerase chain reaction based techniques.

Adenomatous Polyposis Coli (APC) and Deleted in Colon Cancer (DCC

Colon Cancer (DCC

…in Colon Cancer (DCC) genes and for…

…less so forDCCLOH (kappa=0.62).…

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Molecular analyses of tumors are increasingly useful for prognosis and for guiding therapy. Colonoscopic biopsy provides the first source of tissue for most cases of colorectal carcinoma and therefore might become an important source for molecular analyses. We have addressed the question whether molecular analyses of colonoscopic biopsy yield results similar to the findings from the surgical specimen. Further, we analyzed 2 separate areas of the colectomy specimen to assess tumor heterogeneity. We evaluated 3 samples from each of 67 patients for point mutations in the KRAS gene, loss of heterozygosity (LOH) at the Adenomatous Polyposis Coli (APC) and Deleted in Colon Cancer (DCC) genes and for microsatellite instability (MSI) using polymerase chain reaction based techniques. The average time interval between biopsy and surgery was 2.2+/-0.15 weeks. Lesions were from all colon segments and all surgical stages. The degree of agreement between the biopsy and surgical sites was high for APC LOH, MSI, and KRAS mutations (kappa=0.85, 1.00, and 0.93, respectively) but less so for DCC LOH (kappa=0.62). Colonoscopic biopsies are an acceptable source of neoplastic DNA for studies of KRAS, APC LOH, and MSI, but less so for DCC LOH, primarily resulting from technical considerations.

Also flagged:ALAS2pyridoxinesideroblastic anaemia
Journal Article 2006-09-01 No Snippets Percy MJ, Cuthbert RJ, May A, McMullin MF.
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No abstract available.

Also flagged:diabetesIronoverloadiron overload
Journal Article 2006-09-01 ✓ 5 Snippets Acton RT, Barton JC, Passmore LV, Adams PC, Speechley MR, Dawkins FW, Sholinsky P, Reboussin DM, McLaren GD, Harris EL, Bent TC, Vogt TM, Castro O.
In-Text Gene Mentions

Relationships of serum ferritin, transferrin saturation, and HFE mutations and self-reported diabetes in the Hemochromatosis and Iron Overload Screening (HEIRS) study.

<h4>Objective</h4>We evaluated the associations of self-reported diabetes with serum ferritin concentration, transferrin saturation (TfSat), and HFE C282Y and H63D mutations in six racial/ethnic groups recruited at five field centers in the Hemochromatosis and Iron Overload Screening (HEIRS) study.<h4>Research design and methods</h4>Analyses were conducted on 97,470 participants.

…transferrin saturation, andHFEmutations and self-reported…

…diabetes in theHemochromatosisand Iron Overload…

…saturation (TfSat), andHFEC282Y and H63D…

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<h4>Objective</h4>We evaluated the associations of self-reported diabetes with serum ferritin concentration, transferrin saturation (TfSat), and HFE C282Y and H63D mutations in six racial/ethnic groups recruited at five field centers in the Hemochromatosis and Iron Overload Screening (HEIRS) study.<h4>Research design and methods</h4>Analyses were conducted on 97,470 participants. Participants who reported a previous diagnosis of diabetes and/or hemochromatosis or iron overload were compared with participants who did not report a previous diagnosis.<h4>Results</h4>The overall prevalence of diabetes was 13.8%; the highest prevalence was in Pacific Islanders (20.1%). Of all participants with diabetes, 2.0% reported that they also had hemochromatosis or iron overload. The mean serum ferritin concentration was significantly greater in women with diabetes in all racial/ethnic groups and in Native-American men with diabetes than in those without diabetes. The mean serum ferritin concentration was significantly lower in Asian men with diabetes than in those without diabetes. Mean TfSat was lower in participants with diabetes from all racial/ethnic groups except Native-American women than in those without diabetes. There was no significant association of diabetes with HFE genotype. The mean serum ferritin concentration was greater (P < 0.0001) in women with diabetes than in those without diabetes for HFE genotypes except C282Y/C282Y and C282Y/H63D. Log serum ferritin concentration was significantly associated with diabetes in a logistic regression analysis after adjusting for age, sex, racial/ethnic group, HFE genotype, and field center.<h4>Conclusions</h4>Serum ferritin concentration is associated with diabetes, even at levels below those typically associated with hemochromatosis or iron overload.

Also flagged:acute myeloid leukemiaAMLMLL
Journal Article 2006-09-01 ✓ 1 Snippet Stasevich I, Utskevich R, Kustanovich A, Litvinko N, Savitskaya T, Chernyavskaya S, Saharova O, Aleinikova O.
In-Text Gene Mentions

…3' part ofMLLT10in 10p12.…

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Using both conventional and molecular cytogenetic methods, we found five new cases of t(10;11)(p12;q23). This translocation represented 28% of all cases of childhood AML treated at our center in 2004, and 63% of AML with rearrangements of 11q23. We describe three mechanisms for the translocation. Different fragments of 11q were involved in four of the five cases. One patient showed a cytogenetically cryptic insertion of 5' part of MLL into the 3' part of MLLT10 in 10p12. The median event-free survival of patients was 8.1 months, and we conclude that the t(10;11)(p12;q23) is associated with unfavorable prognosis in childhood acute myeloid leukemia.

Also flagged:axonsgrowth conesNeuriteinnervationsynapseneurite growth
Journal Article 2006-09-01 No Snippets Mueller BK, Yamashita T, Schaffar G, Mueller R.
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During the development of the nervous system, outgrowing axons often have to travel long distances to reach their target neurons. In this process, outgrowing neurites tipped with motile growth cones rely on guidance cues present in their local environment. These cues are detected by specific receptors expressed on growth cones and neurites and influence the trajectory of the growing fibres. Neurite growth, guidance, target innervation and synapse formation and maturation are the processes that occur predominantly but not exclusively during embryonic or early post-natal development in vertebrates. As a result, a functional neural network is established, which is usually remarkably stable. However, the stability of the neural network in higher vertebrates comes at an expensive price, i.e. the loss of any significant ability to regenerate injured or damaged neuronal connections in their central nervous system (CNS). Most importantly, neurite growth inhibitors prevent any regenerative growth of injured nerve fibres. Some of these inhibitors are associated with CNS myelin, others are found at the lesion site and in the scar tissue. Traumatic injuries in brain and spinal cord of mammals induce upregulation of embryonic inhibitory or repulsive guidance cues and their receptors on the neurites. An example for embryonic repulsive directional cues re-expressed at lesion sites in both the rat and human CNS is provided with repulsive guidance molecules, a new family of directional guidance cues.

Also flagged:auditory hallucinationspsychosispsychoseshearingFOXP2dopamine
Journal Article 2006-09-01 ✓ 2 Snippets Sanjuan J.
In-Text Gene Mentions

We hypothesize two types of genetic vulnerability: vulnerability to hearing voices -that could be related with genes that are expressed in language areas and are related with language abnormalities (FOXP2)-, and vulnerability to abnormal emotional response to voices -that could be related with genes that are involved in the regulation of dopamine in the limbic system (5-HTT, CCK-AR)-.

…the limbic system (5-HTT, CCK-AR)-.…

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<h4>Introduction</h4>Auditory hallucinations is one of the core symptoms of psychosis. Two main different approaches have been made in recent years in order to understand this perceptual abnormality. The psycho-social approaches is trying to explain auditory hallucinations as a common human phenomenon that only environmental factors cause them to be pathological. It propose psychotherapeutic techniques based on the cognitive model, paying special attention to the emotional component. The neurobiological approach, specially with neuroimaging techniques, is giving us new information about abnormal activation in specific neural networks, particularly in language areas. It propose biological treatments with antipsychotics and transcranial magnetic stimulation. Neither of these approaches are listening to each other. Neither of them look at the molecular genetic vulnerability to auditory hallucinations in psychosis.<h4>Development</h4>From a review of the literature and our own findings, we present a genetic-environmental model of auditory hallucinations in psychoses. We hypothesize two types of genetic vulnerability: vulnerability to hearing voices -that could be related with genes that are expressed in language areas and are related with language abnormalities (FOXP2)-, and vulnerability to abnormal emotional response to voices -that could be related with genes that are involved in the regulation of dopamine in the limbic system (5-HTT, CCK-AR)-. Finally, environmental and cultural factors explain the content and social adjustment to auditory hallucinations.<h4>Conclusion</h4>Our model allow the integration of many data from epidemiology and neuroimaging, to psychopharmacology in the understanding of the aetiology of auditory hallucinations.

Also flagged:Epstein-Barr virus infectioninfectious mononucleosishepatitistransaminaseslactate dehydrogenaseViral illness
Journal Article 2006-09-01 ✓ 1 Snippet Smellie WS, Ryder SD.
In-Text Gene Mentions

HFE

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No abstract available.

Also flagged:ulcersulcerFXIIIvenous ulcerationprimarychronic venous disorder
Journal Article 2006-09-01 ✓ 5 Snippets Gemmati D, Tognazzo S, Catozzi L, Federici F, De Palma M, Gianesini S, Scapoli GL, De Mattei M, Liboni A, Zamboni P.
In-Text Gene Mentions

Conversely, HFE-C282Y, despite its role in ulcer establishment, did not affect the postoperative healing time.

Recently, the HFE-C282Y and FXIII-V34L gene variants demonstrated a role in the risk of venous ulceration in primary chronic venous disorder (CVD) and in modulating lesion size in chronic venous ulcer (CVU), respectively.

This study was conducted to investigate the role of HFE-C282Y and FXIII (V34L and P564L) gene variants in ulcer healing time after superficial venous surgery, by assessing the outcome of a cohort of homogeneous CVU patients.

…Recently, theHFE-C282Y and FXIII-V34L gene…

…the role ofHFE-C282Y and FXIII (V34L…

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<h4>Objective</h4>Role of superficial venous surgery in reducing the time it takes for ulcers to heal is still controversial, although all studies confirm a significant reduction in ulcer recurrences. Recently, the HFE-C282Y and FXIII-V34L gene variants demonstrated a role in the risk of venous ulceration in primary chronic venous disorder (CVD) and in modulating lesion size in chronic venous ulcer (CVU), respectively. This study was conducted to investigate the role of HFE-C282Y and FXIII (V34L and P564L) gene variants in ulcer healing time after superficial venous surgery, by assessing the outcome of a cohort of homogeneous CVU patients.<h4>Methods</h4>The study selected 91 patients affected by primary CVU (CEAP C6, Ep, Asp, Pr), with the exclusion of any other comorbidity factor involved in delayed healing process, who underwent surgery. We assessed the ulcer area and the healing time. Patients were genotyped by polymerase chain reaction for FXIII (V34L and P564L) and for HFE-C282Y substitutions.<h4>Results</h4>Globally, CVU cases had a postoperative mean healing time of 8.5 +/- 5.7 weeks. For the subset of cases above and below the median value (M = 8.0 weeks), FXIII-V34L genotype distribution significantly differed (P < .0001). In addition, Kaplan-Meier analysis yielded specific healing time profiles for the different FXIII-V34L classes of genotype (P = .00001), with an increased risk of delayed healing for the FXIII-VV genotype (hazard ratio, 4.14; 95% confidence interval, 2.1 to 8.2; P = .00005). Although FXIII-P54L genotype distributions did not differ, homozygous 564LL cases (P = .005) and double carriers for both FXIII variants (P < .0001), had a significantly reduced healing time vs wild types. No differences in healing time were observed between carriers and noncarriers of the HFE-C282Y variant, whereas when these cases were stratified by FXIII-V34L genotypes, the L34 carriers had a significantly shorter healing time, irrespective of the HFE genotype.<h4>Conclusion</h4>The FXIII-34L variant was significantly associated with shorter healing time after superficial venous surgery, suggesting a role in the healing and tissue regeneration phases. Conversely, HFE-C282Y, despite its role in ulcer establishment, did not affect the postoperative healing time. In perspective, the identification of patients with a poor prognosis may give clinicians the opportunity to modify management and to target tailored therapies in the view of a new and alternative concept of treatment based on pharmacogenomics.

Also flagged:reninangiotensinkininACEBDKRB2NOS3
Journal Article 2006-09-01 ✓ 3 Snippets Saunders CJ, de Milander L, Hew-Butler T, Xenophontos SL, Cariolou MA, Anastassiades LC, Noakes TD, Collins M.
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BDKRB2 +9/+9 genotype and the 5-HTT SS genotype between the three weight loss

…BDKRB2, NOS3 and/or5-HTTgenes with weight…

…(5-HTTLPR) within the5-HTTgene and the…

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Thirst is regulated by a complex interaction of signalling pathways within the central nervous system, including components of the renin-angiotensin and kalikrein kinin systems, as well as the serotonergic pathways. The aim of this study was to determine whether there were any associations between polymorphisms within the ACE, BDKRB2, NOS3 and/or 5-HTT genes with weight changes during the 2000 and 2001 226 km South African Ironman Triathlons. Pre- and post-race serum [Na(+)] and body weights, as well as genotype data, were collected from 428 (61.1%) Caucasian male triathletes who were divided into three groups according to their relative weight loss during the triathlon (0-3, 3-5 and >5%). There was a significant linear trend for the distribution of both the BDKRB2 +9/+9 genotype and the 5-HTT SS genotype between the three weight loss groups, with the >5% group having the highest percentage of athletes with the +9/+9 genotype (chi(2)=5.3, P=0.021) and the highest percentage of athletes with the SS genotype (chi(2)=5.8, P=0.016). Likewise, the >5% group had the highest percentage of athletes with the combined SS 5-HTT and/or +9/+9 BDKRB2 genotypes (chi(2)=7.4, P=0.007). In conclusion, the functional SS genotype of the serotonin transporter-linked polymorphic region (5-HTTLPR) within the 5-HTT gene and the functional +9/+9 genotype of the BDKBR2 gene were associated with larger weight losses during the Ironman Triathlons. These findings suggest the involvement of the serotonergic pathways in the control of thirst and drinking behaviour and provide further evidence for the dipsogenic effect of circulating bradykinin.

Also flagged:Slc39a14SLC39A zinc transporterzincIL-6SLC39Airon
Journal Article 2006-09-01 ✓ 2 Snippets Liuzzi JP, Aydemir F, Nam H, Knutson MD, Cousins RJ.
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…of patients withhemochromatosisand transfusional iron…

Hfe

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Zip14 is a member of the SLC39A zinc transporter family, which is involved in zinc uptake by cells. Up-regulation of Zip14 by IL-6 appears to contribute to the hepatic zinc accumulation and hypozincemia of inflammation. At least three members of the SLC39A family transport other trace elements, such as iron and manganese, in addition to zinc. We analyzed the capability of Zip14 to mediate non-transferrin-bound iron (NTBI) uptake by overexpressing mouse Zip14 in HEK 293H cells and Sf9 insect cells. Zip14 was found to localize to the plasma membrane, and its overexpression increased the uptake of both (65)Zn and (59)Fe. Addition of bathophenanthroline sulfonate, a cell-impermeant ferrous iron chelator, inhibited Zip14-mediated iron uptake from ferric citrate, suggesting that iron is taken up by HEK cells as Fe(2+). Iron uptake by HEK and Sf9 cells expressing Zip14 was inhibited by zinc. Suppression of endogenous Zip14 expression by using Zip14 siRNA reduced the uptake of both iron and zinc by AML12 mouse hepatocytes. Zip14 siRNA treatment also decreased metallothionein mRNA levels, suggesting that compensatory mechanisms were not sufficient to restore intracellular zinc. Collectively, these results indicate that Zip14 can mediate the uptake of zinc and NTBI into cells and that it may play a role in zinc and iron metabolism in hepatocytes, where this transporter is abundantly expressed. Because NTBI is commonly found in plasma of patients with hemochromatosis and transfusional iron overload, Zip14-mediated NTBI uptake may contribute to the hepatic iron loading that characterizes these diseases.

Also flagged:penicillinpenicillin-binding proteinspbpRestriction enzymepbp2bsystemic disease
Journal Article 2006-09-01 No Snippets Sogstad MK, Høiby EA, Caugant DA.
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A total of 125 non-penicillin-susceptible Streptococcus pneumoniae isolates were received at the Norwegian Institute of Public Health in the period from 1995 to 2001. The strains were tested for antimicrobial susceptibility, serotyped, and genotyped by multilocus sequence typing (MLST); and their penicillin-binding proteins (PBPs) were typed by restriction fragment length polymorphism analysis of their pbp genes. Of the 125 strains, 48 (38%) were fully resistant to penicillin and 77 (62%) were intermediately resistant to penicillin. Most of the strains resistant to penicillin were also resistant to one or several additional antibiotics. The most frequent serotypes among the non-penicillin-susceptible strains were 14, 9V, 19F, 23F, and 6B. MLST analysis showed a high degree of genetic diversity among the 119 strains tested, with a total of 74 different sequence types. Six of the 26 internationally known resistant clones were present; the Spain(9V)-3 clone was the most frequent, with 19 isolates. A total of 74 (62%) of the isolates were related to 1 of the 26 international clones. Restriction enzyme analyses of the pbp1a, pbp2b, and pbp2x genes revealed 12, 12, and 19 different patterns, respectively; and a total of 43 different PBPs types were demonstrated. Our data indicate that the non-penicillin-susceptible strains in Norway are highly diverse genetically and that limited spread of the internationally known resistant strains occurred in the country in the period examined.

Also flagged:BRCA1Canavan diseaseBRCAbreast cancer
Journal Article 2006-09-01 No Snippets Caulfield T, Cook-Deegan RM, Kieff FS, Walsh JP.
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No abstract available.

Also flagged:Serotonin transporteramphetaminedopamine transporterd-amphetamineaddiction
Journal Article 2006-09-01 ✓ 2 Snippets Lott DC, Kim SJ, Cook EH, de Wit H.
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…serotonin transporter gene (HTT) using a double-blind,…

…that these twoHTTpolymorphisms may contribute…

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The authors have previously shown an effect of dopamine transporter genotype on acute subjective responses to d-amphetamine, which may affect risk of addiction. They now report the results of an evaluation of the role of the serotonin transporter gene (HTT) using a double-blind, placebo-controlled, crossover design in which subjects (N = 101) completed self-report measures of subjective effect. The separate and combined analyses of the gene-linked polymorphic region (5-HTTLPR) and the Intron 2 VNTR suggest that these two HTT polymorphisms may contribute to acute subjective responses to d-amphetamine with a small effect.

Also flagged:primary sclerosing cholangitisliver diseaseSkin cancersmall bowel tumorshematologic malignanciesskin cancers
Journal Article 2006-09-01 ✓ 1 Snippet Yao FY, Gautam M, Palese C, Rebres R, Terrault N, Roberts JP, Peters MG.
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hemochromatosis

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<h4>Background</h4>Long-term survival data on de novo malignancy are limited following orthotopic liver transplantation (OLT) when compared with controls without malignancies.<h4>Methods</h4>Over a 12 yr period at our institution, 50 of 1043 patients (4.8%) who underwent OLT were identified to have 53 de novo malignancies. The clinical characteristics and survival of these patients were retrospectively reviewed and compared with a control cohort of 50 OLT recipients without malignancy matched with the incidence cases by age, year of OLT, sex, and type of liver disease.<h4>Results</h4>Chronic hepatitis C, alcohol and primary sclerosing cholangitis were the three leading causes of liver disease. Skin cancer was the most common malignancy (32%), followed by gastrointestinal (21%), including five small bowel tumors, and hematologic malignancies (17%). The cases and controls were not significantly different in the immunosuppressive regimen (p = 0.42) or the number of rejection episodes (p = 0.92). The five- and 10-year Kaplan-Meier survival rates for the cases were 77% and 34%, respectively, vs. 84% and 70%, respectively, for the controls (p = 0.02 by log-rank test). Patients with skin cancers had survival similar to the controls, but significantly better than non-skin cancers (p = 0.0001). The prognosis for patients with gastrointestinal tumors was poor, with a median survival of 8.5 months after the diagnosis.<h4>Conclusion</h4>In this single institutional study, de novo malignancies after OLT were uncommon. Patients with non-skin cancer after OLT had diminished long-term survival compared with the controls. Our results differ from other reports in the high incidence of gastrointestinal malignancies with attendant poor prognosis.

Also flagged:ChaperoninpolyglutamineHuntington's diseaseneurodegenerative disordersHsp70chaperones
Journal Article 2006-09-01 ✓ 2 Snippets Behrends C, Langer CA, Boteva R, Böttcher UM, Stemp MJ, Schaffar G, Rao BV, Giese A, Kretzschmar H, Siegers K, Hartl FU.
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…fragments of huntingtin (Htt) into soluble oligomers…

…to conformationally distinctHttoligomers of approximately…

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Aberrant folding and fibrillar aggregation by polyglutamine (polyQ) expansion proteins are associated with cytotoxicity in Huntington's disease and other neurodegenerative disorders. Hsp70 chaperones have an inhibitory effect on fibril formation and can alleviate polyQ cytotoxicity. Here we show that the cytosolic chaperonin, TRiC, functions synergistically with Hsp70 in this process and is limiting in suppressing polyQ toxicity in a yeast model. In vitro reconstitution experiments revealed that TRiC, in cooperation with the Hsp70 system, promotes the assembly of polyQ-expanded fragments of huntingtin (Htt) into soluble oligomers of approximately 500 kDa. Similar oligomers were observed in yeast cells upon TRiC overexpression and were found to be benign, in contrast to conformationally distinct Htt oligomers of approximately 200 kDa, which accumulated at normal TRiC levels and correlated with inhibition of cell growth. We suggest that TRiC cooperates with the Hsp70 system as a key component in the cellular defense against amyloid-like protein misfolding.

Also flagged:Netrin-1KORembryonal carcinomatranslationallyfocal adhesion kinaseFAK
Journal Article 2006-09-01 ✓ 1 Snippet Tsai NP, Bi J, Loh HH, Wei LN.
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DCC

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The expression of kappa opioid receptor (KOR) is subjected to both transcriptional and posttranscriptional controls. We report that KOR translation is regulated by netrin-1 in primary neurons of dorsal root ganglion (DRG) and in P19 embryonal carcinoma cells. Without stimulation, a significant portion of KOR mRNA is maintained in a dormant state and partitions in the translationally inactive, post-polysomal fraction. During netrin-1 stimulation, which activates its downstream target focal adhesion kinase (FAK), KOR mRNA rapidly partitions to the translationally active polysomal fraction. Functionally, the newly synthesized KOR proteins in DRG neurons are able to bind to specific ligands. This report describes the first example of netrin-1 signaling in the translational control of a drug receptor KOR, which involves the mediator of netrin-1, FAK, and a novel mechanism that enhances the association of target mRNA with polysomes for translational activation.

Also flagged:porphyria cutanea tardahaemochromatosishereditaryiron-overload syndromeironcutanea porphyria
Journal Article 2006-09-01 No Snippets de Geus HR, Dees A.
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Haemochromatosis is a hereditary iron-overload syndrome caused by increased intestinal iron absorption and characterised by accumulation of potentially toxic iron in the tissues. Sometimes this disease presents as a cutanea porphyria. We describe a patient with joint complaints and blistering skin lesions on sun-exposed skin. After identifying the porphyria cutanea tarda by urine analysis we found that the serum activity of uroporphyrinogen decarboxylase (UROD) was normal, meaning a partial inactivation of UROD in liver tissue due to external factors. Further investigation showed the homozygous Cys282Tyr missense mutation and high levels of serum ferritin. It is important to recognise the symptoms of iron overloading at an early stage because hereditary haemochromatosis needs to be treated immediately. We therefore advocate routine sampling of ferritin levels in patients with unexplained joint complaints.

Also flagged:serotonin transporter
Journal Article 2006-09-01 ✓ 2 Snippets Lanzagorta N, Alexanderson-Rosas E, Ricalde A, Gómez Caudillo L, Sosa A, Camarena B, Aguilar A, Fresán A, Apiquián R, Nicolini H.
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…serotonin transporter gene (5-HTT) on personality dimensions…

…of personality and5-HTTgenotypes.…

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<h4>Introduction</h4>The aim of the present study was to assess the association between the serotonin transporter gene and the Temperament and Character Inventory (TCI) personality dimensions in subjects without psychopathology.<h4>Method</h4>Fifty seven individuals without psychiatric symptoms were assessed with the SCL-90, and the TCI. In all subjects a peripheral blood sample was taken to determine their genotypes, after informed consent. Three groups were formed according to the 5-HTT genotype: SS, SL and LL, and the TCI results were compared.<h4>Results</h4>There was no association among the 5-HTT genotypes and any of the TCI subscales. There were also no statistical differences among any of the three groups divided by genotype only according to the TCI scores, as well as when compared with historical controls.<h4>Conclusions</h4>These results are consistent with other studies that have not found associations among the different measurements of personality and 5-HTT genotypes. Likewise, our data suggest that our sample can be useful as a source of controls for later studies. This is the first study assessing TCI dimensions and the 5-HTT gene in the Mexican population.

Also flagged:copperironWilson's diseaseATP7Bcopper toxicosishypoceruloplasminemia
Journal Article 2006-09-01 ✓ 5 Snippets Hayashi H, Yano M, Fujita Y, Wakusawa S.
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This review of the copper-iron interaction in Wilson's disease was mainly based on ten patients (three females and seven males) studied in our institutes because the genetic tests of ATP7B for Wilson's disease of primary copper toxicosis and HFE for hemochromatosis, the biochemical parameters of copper and iron, and morphological studies on biopsied liver specimens were complete.

This review of the copper-iron interaction in Wilson's disease was mainly based on ten patients (three females and seven males) studied in our institutes because the genetic tests of ATP7B for Wilson's disease of primary copper toxicosis and HFE for he

…copper toxicosis andHFEfor hemochromatosis, the…

…and HFE forhemochromatosis, the biochemical parameters…

…mutation, C282Y, ofHFE.…

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This review of the copper-iron interaction in Wilson's disease was mainly based on ten patients (three females and seven males) studied in our institutes because the genetic tests of ATP7B for Wilson's disease of primary copper toxicosis and HFE for hemochromatosis, the biochemical parameters of copper and iron, and morphological studies on biopsied liver specimens were complete. All patients had hypoceruloplasminemia and hepatic lesions compatible with Wilson's disease. One patient was homozygous and nine patients were compound heterozygous for the mutations in ATP7B, and all patients were free from the major mutation, C282Y, of HFE. The biochemical parameters of iron metabolism were not specific, except for serum ferritin concentration. Judging from the traditional criteria, seven patients had hyperferritinemia. Histochemical iron was stained in the livers of seven patients and histochemical copper was found in nine patients. Microanalysis was more sensitive than histochemistry, detecting copper and iron accumulation in the hepatocellular lipofuscin particles of all patients. Using an improved fixative, intralipofuscin distribution was found to be different between cuprothionein and iron complexes. Iron overload in Wilson's disease might be worsened after treatment because of the close relation to hypoceruloplasminemia, in which the iron efflux from the liver to the circulation is disturbed.

Also flagged:peginterferon alfabilharziasisPegIFN-alpha2aIFN alphaRibavirininterferon
Journal Article 2006-09-01 ✓ 1 Snippet Derbala MF, Al Kaabi SR, El Dweik NZ, Pasic F, Butt MT, Yakoob R, Al-Marri A, Amer AM, Morad N, Bener A.
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Hemochromatosis

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<h4>Aim</h4>To evaluate pegylated interferon alpha2a (PegIFN-alpha2a) in Egyptian patients with HCV genotype 4, and the impact of pretreatment viral load, co-existent bilharziasis and histological liver changes on response rate.<h4>Methods</h4>A total of 73 naive patients (61 with history of bilharziasis) with compensated chronic HCV genotype 4 were enrolled into: group A (38 patients) who received 180 mg PegIFN-alpha2a subcutaneously once weekly for a year and group B (35 patients) received IFN alpha-2a 3 MU 3 times weekly. Ribavirin was added to each regimen at a dose of 1200 mg. Patients were followed for 72 wk and sustained response was assessed.<h4>Results</h4>Significant improvement in both end of treatment response (ETR) (P < 0.002) and sustained response (SR) (P < 0.05) was noted with pegylated interferon, where ETR was achieved in 29 (76.3%) and 14 patients (40%) in both groups respectively, and 25 patients in group A (65.8%) and 9 (25.7%) in group B could retain negative viraemia by the end of follow up period. Sustained virological response (SVR) showed a significant negative correlation with age and positive correlation with pretreatment inflammation in patients receiving PegIFN. Viral clearance after 3 mo of therapy was associated with high incidence of ETR and SR (P < 0.001), but without significant difference between both forms of interferon. Significant improvement in response was achieved in patients with high grade fibrosis (grade 3 and 4) with PegIFN-alpha2a, where SR was seen in 5 out of 13 patients in group A, but none in group B. There was no significant difference in response between bilharzial and non-bilharzial patients in both groups. In terms of safety and tolerability, neutropenia was the predominant side effect; both drugs were comparable.<h4>Conclusion</h4>PegIFN-alpha2a combined with ribavirin results in improvement in sustained response in HCV genotype 4, irrespective of history of bilharzial infestation.

Also flagged:carotid diseasegallstonesgallstone diseasefatty livernon-alcoholic fatty liver diseaseNAFLD
Journal Article 2006-09-01 ✓ 1 Snippet Lonardo A, Lombardini S, Scaglioni F, Ballestri S, Verrone AM, Bertolotti M, Carulli L, Ganazzi D, Carulli N, Loria P.
In-Text Gene Mentions

hemochromatosis

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<h4>Aim</h4>To evaluate carotid intima-media thickening (IMT) and plaques, gallstone disease (GD) and fatty liver (FL) as a function of age.<h4>Methods</h4>In 449 subjects, FL and carotid disease were assessed ultrasonographically. In a subgroup of 65/449 patients with non-alcoholic fatty liver disease (NAFLD), carotid disease, GD and associated factors were determined.<h4>Results</h4>FL of unspecified etiology was more common in younger and GD in older individuals. FL subjects had an increased prevalence of IMT and a decreased prevalence of plaques and manifested carotid disease earlier. Plaques were more common in subjects with GD. Age was an independent predictor of carotid disease outcome and FL was a protective factor for plaques. In NAFLD, there was an inverse correlation between body weight and age and the latter independently predicted carotid findings.<h4>Conclusion</h4>Cardiovascular risk in patients with FL and NAFLD needs to be assessed as a function of age and body weight.

Also flagged:ECA39polysaccharidecolorectal adenocarcinomap53c-MycPSK
Journal Article 2006-09-01 ✓ 1 Snippet Yoshikawa R, Yanagi H, Shen CS, Fujiwara Y, Noda M, Yagyu T, Gega M, Oshima T, Yamamura T, Okamura H, Nakano Y, Morinaga T, Hashimoto-Tamaoki T.
In-Text Gene Mentions

DCC

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<h4>Aim</h4>To investigate the possible role of polysaccharide-K (PSK) -related markers in predicting distant metastasis and in the clinical outcome of colorectal cancer (CRC).<h4>Methods</h4>Firstly, we used protein microarrays to analyze the in vitro expression profiles of potential PSK-related markers in the human colorectal adenocarcinoma cell line SW480, which carries a mutant p53 gene. Then, we investigated the clinical implications of these markers in the prognosis of CRC patients.<h4>Results</h4>ECA39, a direct target of c-Myc, was identified as a candidate protein affected by the anti-metastatic effects of PSK. Immunohistochemistry revealed that ECA39 was expressed at significantly higher levels in tumor tissues with distant metastases compared to those without (P<0.00001). Positive ECA39 expression was shown to be highly reliable for the prediction of distant metastases (sensitivity: 86.7%, specificity: 90%, positive predictive value: 86.7%, negative predictive value: 90%). A significantly higher cumulative 5-yr disease free survival rate was observed in the ECA39-negative patient group (77.3%) compared with the ECA39-positive patient group (25.8%) (P<0.05).<h4>Conclusion</h4>Our results suggest that ECA39 is a dominant predictive factor for distant metastasis in patients with advanced CRC and that its suppression by PSK might represent a useful application of immunotherapy as part of a program of integrated medicine.

Also flagged:axoncell bodysynapticaxonalneurodegenerative diseasesAxonal Transport Disorders
Journal Article 2006-09-01 ✓ 2 Snippets Duncan JE, Goldstein LS.
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One common feature of these diseases is that the proteins encoded by genes linked to each disease are transported in the axon and can perturb transport when manipulated; presenilin 1 and APP in AD, Cu/Zn superoxide dismutase (SOD1) in ALS, and huntingtin (Htt) in HD.

HD is a progressive neurodegenerative disorder caused by expansion of CAG triplet repeats in the coding sequence of the huntingtin gene resulting in an expanded polyglutamine tract (polyQ) in the Htt protein and a toxic gain of function.

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Neurons are specialized cells with a complex architecture that includes elaborate dendritic branches and a long, narrow axon that extends from the cell body to the synaptic terminal. The organized transport of essential biological materials throughout the neuron is required to support its growth, function, and viability. In this review, we focus on insights that have emerged from the genetic analysis of long-distance axonal transport between the cell body and the synaptic terminal. We also discuss recent genetic evidence that supports the hypothesis that disruptions in axonal transport may cause or dramatically contribute to neurodegenerative diseases.

Also flagged:depressionAgingserotoninserotonin transporterdementiaanxiety
Journal Article 2006-09-01 ✓ 3 Snippets Grünblatt E, Löffler C, Zehetmayer S, Jungwirth S, Tragl KH, Riederer P, Fischer P.
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The site of effect for the selective serotonin reuptake inhibitors (SSRIs) is the serotonin transporter (5-HTT), which is extensively investigated for its involvement in depressive symptoms.

…the serotonin transporter (5-HTT), which is extensively…

…important role of5-HTTin depression.…

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<h4>Background</h4>The site of effect for the selective serotonin reuptake inhibitors (SSRIs) is the serotonin transporter (5-HTT), which is extensively investigated for its involvement in depressive symptoms. The 5-HTT gene exhibits a 5'-promoter-based length polymorphism (5-HTTLPR) that affects the transcription efficiency and activity, known as short (S) and long (L) alleles. We studied the association of this polymorphism in old age and depression in the Vienna Transdanube Aging (VITA) study, excluding subjects with dementia.<h4>Method</h4>We used retrospective data from the baseline of the VITA study, which is a cohort study of all inhabitants of a geographical area aged 75 years (N = 544). Depression was diagnosed and classified strictly according to the DSM-IV. To eliminate dementia effects, we excluded subjects with a Clinical Dementia Rating higher than or equal to 1 and/or a Mini-Mental State Examination score lower than 24. Genotyping for the 5-HTTLPR L/S allele was conducted using polymerase chain reaction methodology.<h4>Results</h4>We found significantly higher SS genotype frequency in all subjects with past/ present depression compared to controls (trend test, p = .01). The SS genotype frequency was especially high in subjects with onset of depression before age 65. No correlations were found between genotypes/S allele carriers and actual Hamilton Rating Scale for Depression, Short-Geriatric Depression Scale, and anxiety scale scores.<h4>Conclusions</h4>These observations of higher frequency of the 5-HTTLPR S allele in subjects with past/present depression fit with previous findings and point to the important role of 5-HTT in depression.

Also flagged:Histone deacetylaseHuntington's diseasedeathautosomal dominantly inheritedneurodegenerative disorderHD
Journal Article 2006-09-01 No Snippets Sadri-Vakili G, Cha JH.
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Huntington's disease is an autosomal dominantly inherited neurodegenerative disorder caused by a polyglutamine repeat expansion. The onset of HD leads to problems with movement, cognition, and behavioral functioning and there is currently no effective treatment. The mechanism by which mutant huntingtin causes neuronal dysfunction is not known. However, multiple pathologic mechanisms have been discovered. Recent studies provide strong evidence for transcriptional dysregulation as a mechanism of HD pathogenesis. The control of eukaryotic gene expression depends on the modification of histone proteins associated with specific genes; acetylation and deacetylation of histones play a critical role in gene expression. Studies in numerous HD models have shown that mutant huntingtin expression leads to a change in histone acetyl transferase (HAT) activity and suggest that aberrant HAT activity may be an underlying mechanism of transcriptional dysregulation in HD. Furthermore, recent studies have shown a therapeutic role for histone deacetylase (HDAC) inhibitors in a number of HD models. In this review we discuss a number of studies that use HDAC inhibitors as therapeutic agents in HD models. These studies demonstrate that HDAC inhibitors are a promising therapeutic approach for the treatment of HD.

Also flagged:hereditary hemochromatosis
Journal Article 2006-09-01 ✓ 5 Snippets Terzić R, Sehić A, Teran N, Terzić I, Peterlin B.
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Genetic epidemiology studies of hereditary hemochromatosis (HHC) have shown a high prevalence of the C282Y mutation in individuals of the North Western European origin, whereas lower prevalence of HFE gene mutations was detected in the populations from southern European countries.

hereditary hemochromatosis (HHC) have shown a high prevalence of the C282Y mutation in individuals of the North Western European origin, whereas lower prevalence of HFE

…Frequency ofHFEgene mutations C282Y…

…lower prevalence ofHFEgene mutations was…

…However, noHFEmutation prevalence data…

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Genetic epidemiology studies of hereditary hemochromatosis (HHC) have shown a high prevalence of the C282Y mutation in individuals of the North Western European origin, whereas lower prevalence of HFE gene mutations was detected in the populations from southern European countries. However, no HFE mutation prevalence data have been provided for the population of Bosnia-Herzegovina so far. Therefore, the aim of this study was to determine the frequency of the C282Y and H63D HFE gene mutations in the population of Bosnia-Herzegovina. Among 200 analysed subjects 8 (4%) were C282Y heterozygotes; no C282Y homozygotes were found. The frequency of the H63D allele was 11.5%. There were 33 (16.5%) heterozygotes and 6 (3%) homozygotes for the H63D mutation. One (0.5%) compound heterozygote C282Y/H63D was identified. The observed C282Y and H63D allele frequency was 2.25% (95% confidence interval: 1.2-4.2) and 11.5% (95% confidence interval: 8.7-14.9), respectively. The prevalence of the C282Y and H63D mutations was estimated in Bosnia-Herzegovina, which fit well in the European northwest-to-southeast gradient of the C282Y mutation distribution. In addition, these results have an important implication for clinical evaluation of HHC in Bosnia-Herzegovina.

Also flagged:gossypolprostate cancercancercell growthalbuminBSA
Journal Article 2006-09-01 No Snippets Huang YW, Wang LS, Chang HL, Ye W, Sugimoto Y, Dowd MK, Wan PJ, Lin YC.
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<h4>Background</h4>Gossypol, a natural polyphenolic compound present in cottonseeds, possesses antiproliferative and pro-apoptotic effects in in vivo and in vitro models. There are two enantiomers, (+)-gossypol and (-)-gossypol, the latter being a more potent inhibitor of cancer cell growth. Here, the effect of bovine serum albumin (BSA) and dextran-coated charcoal-treated fetal bovine serum (DCC-FBS)-containing medium on the ability of (-)-gossypol to inhibit the growth of human prostate cancer cells was studied.<h4>Materials and methods</h4>BSA- and DCC-FBS-supplemented medium were used to examine the influence of serum proteins on the antiproliferative effects of (-)-gossypol in DU-145 cells, a human prostate cancer cell line. The viability of the DU-145 cells was determined by CellTiter 96 Aqueous assay. The expressions of mRNA and protein for the cell cycle regulators, cyclin-D1, Rb, CDK, p21 and TGF-beta, were determined by RT-PCR and Western blot analyses, respectively.<h4>Results</h4>(-)-Gossypol caused growth suppression of the DU-145 cells. In comparison with BSA-supplemented medium, DCC-FBS blocked the antiproliferative effects of (-)-gossypol at 1 and 2.5 microM, but not at 5 microM. Furthermore, (-)-gossypol treatment down-regulated cyclin-D1, Rb, CDK4 and CDK6, and up-regulated p21 and TGF-beta1 at the mRNA and/or protein levels.<h4>Conclusion</h4>The data suggested that (-)-gossypol-suppressed prostate cancer cell growth may be influenced through cell cycle regulators, which may lead to better prognosis. We further speculate that (-)-gossypol might serve as a chemotherapeutic agent for human prostate cancer patients.

Journal Article 2006-09-01 ✓ 1 Snippet Grassi W, Testi D.
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…ch; again FC-72 and HFE-7100 for the single…

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With the present article, the authors summarize over 15 years of work dedicated to studying the effects of the electrical and the gravitational force fields on two-phase and single-phase thermofluid dynamics. Results obtained on several microgravity platforms are presented and the role played by the electric field in the different heat transfer processes is analyzed. In particular, the regimes of nucleate boiling and film boiling are treated. Also, the parameters controlling the liquid-vapor interface instability and the main consequences regarding the critical heat flux (CHF) are outlined. In the final section, the promising technique of ion injection for efficient heat transfer enhancement in single-phase liquids is described, together with the main results obtained under different flow regimes and geometries. The following dielectrics were compared: R113, Vertrel XF, and FC-72 for the pool boiling research; again FC-72 and HFE-7100 for the single-phase convection heat transfer experiments.

Journal Article 2006-09-01 ✓ 1 Snippet Grassi W, Testi D, Della Vista D, Torelli G.
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…The working fluid, HFE-7100, is a weakly po…

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The heat transfer characteristics of an electrohydrodynamically induced submerged impinging liquid flow are studied in a point-plane configuration. The working fluid, HFE-7100, is a weakly polar dielectric. Thermofluid-dynamic conditions as close as possible to the microgravity ones are obtained by heating a confined, downward-facing plate. Heat transfer coefficients on the plate can be stably enhanced by over 10 times, with negligible additional work, by means of the ion injection technique.

Also flagged:CYP2D6cytochrome P-450CYPhemeterminal oxidasesmixed function oxidases
Journal Article 2006-09-01 ✓ 1 Snippet Lavandera JV, Parera VE, Batlle A, Buzaleh AM.
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HFE

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The cytochrome P-450 (CYP) isoenzymes, a superfamily of heme proteins which are the terminal oxidases of the mixed function oxidases system, metabolize more than 70% of all clinically approved drugs. The highly polymorphic CYP2D6 isoform metabolizes more than 25% of most common drugs, and the phenotypes of the 70-plus allelic variants range from compromised to excessive enzymatic activity. Porphyrias are a group of inherited or acquired metabolic disorders of heme biosynthesis, due to a specific decrease in the activity of one of the enzymes of the heme pathway. Clinical signs and symptoms of porphyrias are frequently associated with exposure to precipitating agents, including clinically approved drugs. CYP enzymes, including CYP2D6, participate in the metabolism of some porphyrinogenic drugs, leading to the deregulation of heme biosynthesis. Considering that some of the drugs not recommended for use in porphyric patients are metabolized by CYP2D6, the presence of CYP2D6 polymorphisms in porphyric patients would influence the triggering of the disease when these individuals receive a precipitating agent that is metabolized by CYP2D6. To investigate CYP2D6 polymorphisms in porphyric patients, healthy Argentinean volunteers, porphyric patients, and a group of individuals with high levels of iron were studied. Results indicated that the CYP2D6*3 and CYP2D6*4 alleles, in particular, would be linked to the onset of disease. Predictive genotyping for CYP2D6 in porphyric patients holds promise as a method to improve the clinical efficacy of drug therapy and to personalize drug administration for these patients.

Also flagged:genetic disorderβ-thalassemiahemolytic anemiasynthesisthalassemiathalassemia intermedia
Journal Article 2006-09-01 ✓ 1 Snippet Karamifar H, Karimi M, Amirhakimi GH, Badiei M.
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…overload and secondaryhemochromatosishave been described…

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<h4>Unlabelled</h4>Thalassemias are the most common genetic disorder on a wordwide basis. β-thalassemia is a severe hemolytic anemia which results from genetic defects in the synthesis of the hemoglobin β-chain. Various endocrine abnormalities have been described in patients with thalassemia major. Endocrine disturbances have also been observed in patients with thalassemia intermedia (TI). In this study endocrine functions were investigated in TI and here the frequency of different abnormalities is reported. Ninety-three patients (40 males, 53 females) with thalassemia intermedia, 11-40 years old (mean 19.4 yr) were studied. Medical history was obtained and a complete physical examination was done for each patient. The age, sex, weight, height and serum ferritin levels were recorded using a questionnaire. Growth Hormone (GH) secretion, thyrotropin (TSH), T(4), parathyroid hormone (PTH) and cortisole levels were determined in these patients. The mean ± Standard Deviation (SD) serum ferritin level was 452.4 ± 312.60 μg/L. Mean ± SD hemoglobin concentration was 9 ± 1 g/dl. Short stature was present in 46% of patients. Growth hormone deficiency was one of the most frequent (31%) endocrine abnormalities in these patients. Primary hypothyroidism was observed in 21.5% of patients. Hypoparathyroidism was found in one patient (1%). Failure of puberty was present in 2% of patients, secondary ammenorrhea was observed in 6.4% of patients and diabetes mellitus (DM) in 2% of patients.<h4>Conclusion</h4>Growth retardation and GH deficiency should be considered as common finding in TI. Therefore endocrine evaluation of these patients is suggested to prevent complications and to improve the overall quality of life.