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Viewing September 2000 — 46 paper(s) from the local store. (Local view only — run without --view to fetch new papers.)
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Also flagged:Estrogen receptorbreast cancersoestradioloestrogen receptorERamino
Journal Article 2000-09-06 ✓ 5 Snippets Maaroufi Y, Lacroix M, Lespagnard L, Journé F, Larsimont D, Leclercq G.
In-Text Gene Mentions

For this purpose, cytosols from a set of 15 ER-positive tumours (by DCC assay), for which nuclear ERs had been detected by immunohistochemistry (IS cutoff ≥ 5), were labelled with [3H]oestradiol and were then subjected to hydroxylapatite assay (Table 3).

Moreover, a good correlation was obtained when the amount of 6.6-kb ER mRNA estimated by densitometry was compared with corresponding [3H]oestradiol-binding capacities (DCC values; Fig. 4).

Breast cancer cytosols classified as ER-positive according to [3H]oestradiol-binding assay (dextran-coated charcoal [DCC]) were subjected to hydroxylapatite adsorption.

ER preparations were labelled with increasing concentrations of [3H]oestradiol (range 0.25-5 nmol/l) in the absence and presence of a 200-fold excess of unlabelled oestradiol (overnight incubation at 0°C) and unbound ligands were removed using the DCC adsorption method (0.5% charcoal, 0.05% dextran) [29].

For both [3H]oestradiol- and [125I]TAZ labelled-ER isoforms, we found an excellent correlation between DCC values and hydroxylapatite adsorption data, suggesting the concomitant presence of free ABC and E domains in most cytosols (proteolytic fragments physically separated from each other at high ionic strength; high EI values).

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Iodinated oestradiol-labeled oestrogen receptor (ER) isoforms devoid of amino-terminal ABC domains represent about two-thirds of the whole receptor population detected in cytosol samples from human breast cancers. This high frequency could not be ascribed to the expression of truncated mRNAs, or to the proteolysis of the native ER peptide at the time of homogenization or assay, suggesting an intracellular proteolysis. Free amino-terminal and ligand-binding domains maintained together within oligomeric structure(s); increase of ionic strength separated them. The amino-terminal region was consistently detected in the cell nucleus by specific immunohistochemistry leading to the concept of a potential intranuclear association between ER cleavage products and/or other regulatory proteins.

Also flagged:peptidecaspases 1proteasesanthranilic acidnitrotyrosine
Journal Article 2000-09-01 No Snippets Stennicke HR, Renatus M, Meldal M, Salvesen GS.
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Subsite interactions are considered to define the stringent specificity of proteases for their natural substrates. To probe this issue in the proteolytic pathways leading to apoptosis we have examined the P(4), P(1) and P(1)' subsite preferences of human caspases 1, 3, 6, 7 and 8, using internally quenched fluorescent peptide substrates containing o-aminobenzoyl (also known as anthranilic acid) and 3-nitro-tyrosine. Previous work has demonstrated the importance of the S(4) subsite in directing specificity within the caspase family. Here we demonstrate the influence of the S(1) and S(1)' subsites that flank the scissile peptide bond. The S(1) subsite, the major specificity-determining site of the caspases, demonstrates tremendous selectivity, with a 20000-fold preference for cleaving substrates containing aspartic acid over glutamic acid at this position. Thus caspases are among the most selective of known endopeptidases. We find that the caspases show an unexpected degree of discrimination in the P(1)' position, with a general preference for small amino acid residues such as alanine, glycine and serine, with glycine being the preferred substituent. Large aromatic residues are also surprisingly well-tolerated, but charged residues are prohibited. While this describes the general order of P(1)' subsite preferences within the caspase family, there are some differences in individual profiles, with caspase-3 being particularly promiscuous. Overall, the subsite preferences can be used to predict natural substrates, but in certain cases the cleavage site within a presumed natural substrate cannot be predicted by looking for the preferred peptide cleavage sites. In the latter case we conclude that second-site interactions may overcome otherwise sub-optimal cleavage sequences.

Also flagged:chromosometumourschromosomal regioncolorectal carcinomacolorectal carcinomascentromere
Journal Article 2000-09-01 No Snippets Lee AS, Seo YC, Chang A, Tohari S, Eu KW, Seow-Choen F, McGee JO.
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Loss of heterozygosity (LOH) is frequent at the chromosomal region 11q22-q23 in several types of tumours of diverse cell origin. Previous investigations of LOH at this chromosomal region in colorectal carcinoma have been contradictory in their findings, and have only included between 1-4 loci. In order to define any regions of LOH on 11q23, we investigated 16 loci between D11S940 and D11S934 on the long arm of chromosome 11 using microsatellite analysis. Of 57 colorectal carcinomas specimens, 36 (63.2%) demonstrated LOH at one or more marker, with the highest frequencies of LOH at D11S1340 (41.0%), located between 105.13-111.97 Mb from the centromere, and D11S924 (37.1%) and D11S4107 (40.5%), both located approximately 113 Mb from the centromere. No statistically significant associations between LOH and age-of-presentation or Dukes' stage were found. LOH was observed in colorectal tumours of all Dukes' stages, including Dukes' stages A and B, suggesting that the inactivation of a tumour suppressor gene(s) on 11q23 occurs in the early stages of colorectal carcinoma. These results confirm the presence of putative tumour suppressor gene(s) at chromosome 11q23, involved in the carcinogenesis of colorectal carcinoma, and will facilitate future identification of candidate genes.

Also flagged:protein kinase C alphaprotein kinase CPKCoestrogen receptorERtumours
Journal Article 2000-09-01 No Snippets Tonetti DA, Chisamore MJ, Grdina W, Schurz H, Jordan VC.
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An inverse relationship between protein kinase C (PKC) activity and oestrogen receptor (ER) expression in human breast cell lines and tumours has been firmly established over the past 10 years. To determine whether specific alterations in PKC expression accompany hormone-independence, we examined the expression of PKC isozymes in the hormone-independent human breast cancer cell clones MCF-7 5C and T47D:C42 compared with their hormone-dependent counterparts, MCF-7 A4, MCF-7 WS8 and T47D:A18 respectively. Both hormone-independent cell clones exhibit elevated PKC alpha expression and increased basal AP-1 activity compared with the hormone-dependent cell clones. To determine whether PKC alpha overexpression is sufficient to mediate the hormone-independent phenotype, we stably transfected an expression plasmid containing PKC alpha cDNA to the T47D:A18 and MCF-7 A4 cell lines. This is the first report of PKC alpha transfection in T47D cells. In contrast to MCF-7 cells, T47D has the propensity to lose the ER and more readily forms tamoxifen-stimulated tumours in athymic mice. We find that in T47D:A18/PKC alpha clones, there is concomitant up-regulation of PKC beta I and delta, whereas in the MCF-7 A4/PKC alpha transfectants PKC epsilon is up-regulated. In T47D:A18, but not in MCF-7 A4, PKC alpha stable transfection is accompanied by down-regulation of ER function whilst basal AP-1 activity is elevated. Our results suggest PKC alpha overexpression may play a role in growth signalling during the shift from hormone dependent to hormone-independent breast cancers.

Also flagged:HuntingtinHuntington's diseasepathogenesisglutamineHDspliceosome
Journal Article 2000-09-01 ✓ 1 Snippet Passani LA, Bedford MT, Faber PW, McGinnis KM, Sharp AH, Gusella JF, Vonsattel JP, MacDonald ME.
In-Text Gene Mentions

Huntingtin's WW domain partners in Huntington's disease post-mortem brain fulfill genetic criteria for direct involvement in Huntington's disease pathogenesis.

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An elongated glutamine tract in mutant huntingtin initiates Huntington's disease (HD) pathogenesis via a novel structural property that displays neuronal selectivity, glutamine progressivity and dominance over the normal protein based on genetic criteria. As this mechanism is likely to involve a deleterious protein interaction, we have assessed the major class of huntingtin interactors comprising three WW domain proteins. These are revealed to be related spliceosome proteins (HYPA/FBP-11 and HYPC) and a transcription factor (HYPB) that implicate huntingtin in mRNA biogenesis. In HD post-mortem brain, specific antibody reagents detect each partner in HD target neurons, in association with disease-related N-terminal morphologic deposits but not with filter trapped insoluble-aggregate. Glutathione S:-transferase partner 'pull-down' assays reveal soluble, aberrantly migrating, forms of full-length mutant huntingtin specific to HD target tissue. Importantly, these novel mutant species exhibit exaggerated WW domain binding that abrogates partner association with other huntingtin isoforms. Thus, each WW domain partner's association with huntingtin fulfills HD genetic criteria, supporting a direct role in pathogenesis. Our findings indicate that modification of mutant huntingtin in target neurons may promote an abnormal interaction with one, or all, of huntingtin's WW domain partners, perhaps altering ribonucleoprotein function with toxic consequences.

Also flagged:XCAP-D2histone H3maintenance of chromosomeschromosomeshCAP-ChCAP-E
Journal Article 2000-09-01 ✓ 2 Snippets Schmiesing JA, Gregson HC, Zhou S, Yokomori K.
In-Text Gene Mentions

…A HumanCondensinComplex Containing hCAP-C–hCAP…

Condensin

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Structural maintenance of chromosomes (SMC) family proteins play critical roles in structural changes of chromosomes. Previously, we identified two human SMC family proteins, hCAP-C and hCAP-E, which form a heterodimeric complex (hCAP-C-hCAP-E) in the cell. Based on the sequence conservation and mitotic chromosome localization, hCAP-C-hCAP-E was determined to be the human ortholog of the Xenopus SMC complex, XCAP-C-XCAP-E. XCAP-C-XCAP-E is a component of the multiprotein complex termed condensin, required for mitotic chromosome condensation in vitro. However, presence of such a complex has not been demonstrated in mammalian cells. Coimmunoprecipitation of the endogenous hCAP-C-hCAP-E complex from HeLa extracts identified a 155-kDa protein interacting with hCAP-C-hCAP-E, termed condensation-related SMC-associated protein 1 (CNAP1). CNAP1 associates with mitotic chromosomes and is homologous to Xenopus condensin component XCAP-D2, indicating the presence of a condensin complex in human cells. Chromosome association of human condensin is mitosis specific, and the majority of condensin dissociates from chromosomes and is sequestered in the cytoplasm throughout interphase. However, a subpopulation of the complex was found to remain on chromosomes as foci in the interphase nucleus. During late G(2)/early prophase, the larger nuclear condensin foci colocalize with phosphorylated histone H3 clusters on partially condensed regions of chromosomes. These results suggest that mitosis-specific function of human condensin may be regulated by cell cycle-specific subcellular localization of the complex, and the nuclear condensin that associates with interphase chromosomes is involved in the reinitiation of mitotic chromosome condensation in conjunction with phosphorylation of histone H3.

Also flagged:genetic hemochromatosisironatherosclerosiscell proliferationlipidGH
Journal Article 2000-09-01 ✓ 3 Snippets Failla M, Giannattasio C, Piperno A, Vergani A, Grappiolo A, Gentile G, Meles E, Mancia G.
In-Text Gene Mentions

…with uncomplicated genetichemochromatosis(GH) who were…

…in patients withhemochromatosis, arterial wall thickness…

…early abnormality ofhemochromatosis.…

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Iron overload is believed to have an adverse influence on the cardiovascular system and animal studies have shown that iron may be involved in the events that lead to atherosclerosis via an enhancement of smooth muscle cell proliferation, lipid oxidation, and free radical production. There are no data on the effect of iron overload on arterial structural and mechanical properties in humans. We measured wall thickness and distensibility (D) by ultrasonography of the radial artery in 12 patients with uncomplicated genetic hemochromatosis (GH) who were normotensive and without atherosclerotic plaques. Twelve age- and sex-matched patients were taken as controls. Nine patients were evaluated also after iron depletion. Wall thickness was greater in patients with GH than in controls (+50%, P <.01) whereas D was slightly reduced in the former group compared with the latter group, though the difference was not statistically significant. After iron depletion, a significant reduction of wall thickness and a significant increase in D were observed (-24% and +33%, P <.05 for both). Thus, in patients with hemochromatosis, arterial wall thickness is increased before the onset of cardiovascular complications. This alteration is reverted by iron depletion, which also can improve the initial and modest radial artery wall stiffening associated with this condition. Thus, functional and structural alterations in midsize muscle arteries may be an early abnormality of hemochromatosis.

Also flagged:serotonin transporterschizophreniaclozapineSerotoninpathogenesis5-HTTLPR
Journal Article 2000-09-01 ✓ 3 Snippets Tsai SJ, Hong CJ, Yu YW, Lin CH, Song HL, Lai HC, Yang KH.
In-Text Gene Mentions

The present study tested the hypothesis that a biallelic polymorphism in the 5' regulatory region of the 5-HTT gene (5-HTTLPR) confers susceptibility to schizophrenia, association with the clinical manifestations of schizophrenia or clozapine response.

Following serotonin release, the serotonin transporter (5-HTT) is the major determinant of serotonin inactivation.

…the serotonin transporter (5-HTT) is the major…

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Serotonin is implicated in the pathogenesis of schizophrenia. Following serotonin release, the serotonin transporter (5-HTT) is the major determinant of serotonin inactivation. The present study tested the hypothesis that a biallelic polymorphism in the 5' regulatory region of the 5-HTT gene (5-HTTLPR) confers susceptibility to schizophrenia, association with the clinical manifestations of schizophrenia or clozapine response. 90 treatment-resistant schizophrenic patients were assessed using the Brief Psychiatric Rating Scale before and after clozapine treatment. The results demonstrated that the 5-HTTLPR variants did not play a major role in the susceptibility, clinical manifestations or clozapine response in schizophrenia.

Also flagged:Netrin-G1glycosylphosphatidylinositolaxonmembranephosphatidyl
Journal Article 2000-09-01 ✓ 1 Snippet Nakashiba T, Ikeda T, Nishimura S, Tashiro K, Honjo T, Culotti JG, Itohara S.
In-Text Gene Mentions

DCC

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UNC-6/netrins compose a small phylogenetically conserved family of proteins that act as axon guidance cues. With a signal sequence trap method, we isolated a cDNA encoding a novel member of the UNC-6/netrin family, which we named netrin-G1. Unlike classical netrins, netrin-G1 consists of at least six isoforms of which five were predominantly anchored to the plasma membrane via glycosyl phosphatidyl-inositol linkages. Netrin-G1 transcripts were first detected in midbrain and hindbrain regions by embryonic day 12 and reached highest levels at perinatal stages in various brain regions, including olfactory bulb mitral cells, thalamus, and deep cerebellar nuclei. Its expression was primarily restricted to the CNS. Interestingly, netrin-G1 proteins did not show appreciable affinity to any netrin receptor examined. Unlike netrin-1, a secreted form of netrin-G1 consistently failed to attract circumferentially growing axons from the cerebellar plate. Our findings suggest that netrin-G1 and its putative receptors have coevolved independently from the classical netrins. The expression pattern of netrin-G1 and its predicted neuronal membrane localization suggest it may also have novel signaling functions in nervous system development.

Also flagged:ironDivalent metal transporter 1DMT1SFTtransmembranegene expression
Journal Article 2000-09-01 ✓ 3 Snippets Tallkvist J, Bowlus CL, Lönnerdal B.
In-Text Gene Mentions

…transporter 1 (DMT1),HFE, and stimulator of…

…expression of DMT1,HFE, and SFT in…

…expression of DMT1,HFE, and SFT was…

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<h4>Background</h4>Divalent metal transporter 1 (DMT1), HFE, and stimulator of iron transport (SFT) are transmembrane proteins that have been implicated in the regulation of iron homeostasis.<h4>Objective</h4>The objective of this study was to investigate whether absorption and transepithelial movement of iron correlated with gene expression of DMT1, HFE, and SFT in an experimental model of human absorptive enterocytes.<h4>Design</h4>Caco-2 cells were exposed to iron-supplemented media in either the presence or the absence of serum for 24, 72, and 168 h. At each time point, the uptake and transepithelial movement of iron were examined and gene expression of DMT1, HFE, and SFT was measured. Manganese and zinc absorption was also examined at 168 h.<h4>Results</h4>Iron treatment in the presence or absence of serum reduced the uptake and transepithelial movement of iron by approximately 50% after 72 and 168 h. No effect was observed at 24 h. The uptake and transepithelial movement of manganese were similar to those of iron at 168 h, whereas the effects on zinc were less pronounced. In the absence of serum, iron treatment was associated with a reduction of DMT1 expression by 50% at 72 and 168 h. HFE expression was dependent on serum, but iron treatment did not alter HFE expression. SFT expression was not affected by iron.<h4>Conclusions</h4>Iron treatment decreased cellular uptake of iron, manganese, and zinc, suggesting that these metals may utilize the same apical transporter. The transepithelial movement of iron and manganese, but not of zinc, was reduced across iron-treated Caco-2 cells, suggesting that iron and manganese are regulated by the same mechanism at the basolateral membrane. The gene expression of DMT1, HFE, and SFT did not fully correlate with the functional responses of Caco-2 cells. This may have been a result of posttranscriptional regulation of these genes or regulation of other genes involved in the uptake and transepithelial movement of iron in Caco-2 cells.

Also flagged:transmembraneneurotactincell adhesioncholinesterasecell adhesion moleculeaxon guidance
Journal Article 2000-09-01 ✓ 1 Snippet Frémion F, Darboux I, Diano M, Hipeau-Jacquotte R, Seeger MA, Piovant M.
In-Text Gene Mentions

DCC

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Neurotactin (NRT), a member of the cholinesterase-homologous protein family, is a heterophilic cell adhesion molecule that is required for proper axon guidance during Drosophila development. In this study, we identify amalgam (AMA), a member of the immunoglobulin superfamily, as a ligand for the NRT receptor. Using transfected Schneider 2 cells and embryonic primary cultures, we demonstrate that AMA is a secreted protein. Furthermore, AMA is necessary for NRT-expressing cells both to aggregate with themselves and to associate with embryonic primary culture cells. Aggregation assays performed with truncated NRT molecules reveal that the integrity of the cholinesterase-like extracellular domain was not required either for AMA binding or for adhesion, with only amino acids 347-482 of the extracellular domain being necessary for both activities. Moreover, the NRT cytoplasmic domain is required for NRT-mediated adhesion, although not for AMA binding. Using an ama-deficient stock, we find that ama function is not essential for viability. Pupae deficient for ama do exhibit defasciculation defects of the ocellar nerves similar to those found in nrt mutants.

Also flagged:veno-occlusive diseasethrombinfibrinogenFactor VIIProtein Ctissue plasminogen activator
Journal Article 2000-09-01 ✓ 1 Snippet Villalón L, Avello AG, César J, Odriozola J, López J, Oteyza JP, Laraña JG, Cantalapiedra A, Navarro JL.
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…Protein C, andantithrombin-III), probably as a…

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The objective of the present study was to analyze whether veno-occlusive disease (VOD) is based on specific findings or whether this syndrome is the exacerbation of changes in hemostatic parameters that develop following hematopoietic stem cell transplantation (HSCT). 40 patients undergoing HSCT were enrolled (6 allogeneic bone marrow transplantation and 34 peripheral stem cell rescue-2 allogeneic, 32 autologous). Measurements of hemostatic parameters (endothelial, hypercoagulability and fibrinolytic markers) were obtained prior to chemotherapy and weekly thereafter for 3 weeks. The incidence of VOD was 15%. HSCT showed a state of moderate hypercoagulability (increase of thrombin-antithrombin complex and fibrinogen, and decrease of Factor VII, Protein C, and antithrombin-III), probably as a consequence of marked endothelial damage (increase of von Willebrand Factor and tissue plasminogen activator). All these alterations create a potentially prothrombotic state, more pronounced in VOD. The decreasing incidence of VOD and the moderate disease in all patients suggest that increasing improvements in transplant strategies have reduced the risk and severity of a syndrome that at the beginning of the transplantation era was a leading cause of morbidity/mortality.

Also flagged:histonebindingchromatintranslational modificationscore histoneshistones
Journal Article 2000-09-01 ✓ 1 Snippet Zlatanova J, Caiafa P, Van Holde K.
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…the involvement oflinker histoneshistones in transcriptional…

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In recent years, the connection between chromatin structure and its transcriptional activity has attracted considerable experimental effort. The post-translational modifications to both the core histones and the linker histones are finely tuned through interactions with transcriptional regulators and change chromatin structure in a way to allow transcription to occur. Here we review evidence for the involvement of linker histones in transcriptional regulation and suggest a scenario in which the reversible and controllable binding/displacement of proteins of this class to the nucleosome entry/exit point determine the accessibility of the nucleosomal DNA to the transcriptional machinery.

Also flagged:ironhereditary hemochromatosisiron deficiency anemia
Journal Article 2000-09-01 ✓ 5 Snippets Beutler E, Felitti V, Gelbart T, Ho N.
In-Text Gene Mentions

Heterozygotes for HFE mutations had a lower prevalence of iron deficiency anemia.

The effect of HFE genotypes on measurements of iron overload in patients attending a health appraisal clinic.

The gene that causes most cases of hereditary hemochromatosis is designated HFE.

The prevalence of iron deficiency anemia was lower in women who carried HFE mutations.<h4>Conclusions</h4>Screening for transferrin saturation and ferritin levels does not detect all homozygotes for the major hemochromatosis mutation.

…The effect ofHFEgenotypes on measurements…

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<h4>Background</h4>The gene that causes most cases of hereditary hemochromatosis is designated HFE. Three mutations exist at this locus at a relatively high gene frequency.<h4>Objective</h4>To determine the gene frequency of the three HFE mutations and to relate genotypes to various clinical and laboratory variables.<h4>Design</h4>Observational study.<h4>Setting</h4>Health appraisal clinic.<h4>Patients</h4>10,198 adults who registered for health appraisal and consented to DNA examination for hemochromatosis. Consenting patients were slightly older and had attained a slightly higher educational level than nonconsenting patients.<h4>Measurements</h4>Extensive medical history and laboratory tests, including complete blood count, transferrin saturation, and other chemistries; serum ferritin levels; and HFE genotype.<h4>Results</h4>In white participants, the gene frequencies were 0.063 for the C282Y mutation, 0.152 for the H63D mutation, and 0.016 for the S65C mutation. Gene frequencies were lower in other ethnic groups. In participants with HFE mutations, the average serum transferrin saturation and ferritin levels were slightly increased, as were mean hemoglobin levels and mean corpuscular volume. A transferrin saturation of 50% had a sensitivity of only 0.52 (95% CI, 0.345 to 0.686) and a specificity of 0.908 (CI, 0.902 to 0.914) for detection of homozygosity. A ferritin level of 200 microg/L in women and 250 microg/L in men had a sensitivity of 0.70 (CI, 0.540 to 0.854) and a specificity of 0.803 (CI, 0.796 to 0.811). The prevalence of iron deficiency anemia was lower in women who carried HFE mutations.<h4>Conclusions</h4>Screening for transferrin saturation and ferritin levels does not detect all homozygotes for the major hemochromatosis mutation. Heterozygotes for HFE mutations had a lower prevalence of iron deficiency anemia.

Also flagged:Serotonin transporterparoxetinebindingalcoholbindings5-HTTLPR
Journal Article 2000-09-01 ✓ 1 Snippet Preuss UW, Soyka M, Bahlmann M, Wenzel K, Behrens S, de Jonge S, Krüger M, Bondy B.
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…region serotonin transporter (5-HTT) polymorphism (5-HTTLPR).…

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The aim of this study was to investigate [3H]paroxetine binding and impulsivity in alcohol-dependent and age-matched control subjects in relation to a 5'-promoter region serotonin transporter (5-HTT) polymorphism (5-HTTLPR). Alcohol-dependent subjects were hypothesized to show a decreased number of bindings sites and a lower dissociation constant. 5-HTTLPR S-genotype carriers in both alcohol-dependent and control subjects were expected to show significantly fewer binding sites and a lower dissociation constant. Influences of impulsive traits, chronic daily alcohol intake, duration of alcohol dependence, age of onset and age on [3H]paroxetine binding were also investigated. Inpatients meeting DSM IV alcohol dependence criteria and of German descent were recruited to avoid ethnic stratification effects. One hundred and seventeen control subjects of similar social status were recruited from a town community. Blood samples were taken from both alcohol-dependent and control subjects to determine 5-HTTLPR genotypes using PCR of lymphocyte DNA, and to perform platelet [3H]paroxetine binding (binding capacity: B(max); and dissociation constant: K(D)). Impulsivity was assessed using the Barratt impulsiveness scale version 5 (BIS-5) in alcohol-dependent subjects only. Alcohol-dependent subjects were subdivided into low or high impulsivity groups using a median-split of the BIS-5 scale. The control group was slightly older than the alcohol-dependent group (not statistically significant). [3H]paroxetine binding was investigated in 72 control subjects and 72 patients, of which five patients met type 2 alcohol dependence criteria. Genotyping was carried out in all patients and control subjects. A significant influence of duration of alcohol dependence was found on the [3H]paroxetine binding K(D) but not B(max.) Neither alcohol-dependent nor control subjects showed any differences in B(max) or K(D). S-allele carriers did not show a decreased binding or lower dissociation constant. Furthermore, no significant interaction between B(max) and K(D) with either 5-HTTLPR genotype or impulsivity was revealed. This was the first study to investigate platelet [3H]paroxetine binding in alcohol-dependent and age-matched control subjects in relation to the 5-HTTLPR genotype. No differences concerning 5-HTTLPR-alleles were found in these groups Furthermore, no significant interaction between these parameters and impulsivity was shown in alcohol-dependent subjects. These results do not support previous results of altered [3H]paroxetine binding sites in alcohol-dependent subjects or 5-HTTLPR S-allele carriers. K(D) might be influenced by duration of alcohol dependence, but not sufficiently to yield differences between alcohol-dependent and control subjects.

Also flagged:chondrocyte differentiationtranscription factorsproalpha1(II) collagenCol2a1transcription factorSox9
Journal Article 2000-09-01 ✓ 5 Snippets de Crombrugghe B, Lefebvre V, Behringer RR, Bi W, Murakami S, Huang W.
In-Text Gene Mentions

Two other members of the Sox family, L-Sox5 and Sox6, also bind to the 48-bp Col2a1 enhancer and together with Sox9 activate this enhancer as well as the endogenous Col2a1 and aggrecan genes.

…family, L-Sox5 andSox6, also bind to…

…L-Sox5 andSox6have a high…

…HMG-box, L-Sox5 andSox6have no similarity…

…Sox9, Sox5 andSox6might also be…

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With the goal of identifying master transcription factors that control the genetic program of differentiation of mesenchymal cells into chondrocytes, we first delineated a 48-bp chondrocyte-specific enhancer element in the gene for proalpha1(II) collagen (Col2a1), an early and abundant marker of chondrocytes. Our experiments have demonstrated that the HMG-box-containing transcription factor, Sox9 which binds and activates this enhancer element, is required for chondrocyte differentiation and for expression of a series of chondrocyte-specific marker genes including Col2a1, Col9a2, Col11a2 and Aggrecan. In the absence of Sox9 the block in differentiation occurs at the stage of mesenchymal condensation, suggesting the hypothesis that Sox9 might also control expression of cell surface proteins needed for mesenchymal condensation. Since Sox9 also contains a potent transcription activation domain, it is a typical transcription factor. Two other members of the Sox family, L-Sox5 and Sox6, also bind to the 48-bp Col2a1 enhancer and together with Sox9 activate this enhancer as well as the endogenous Col2a1 and aggrecan genes. L-Sox5 and Sox6 have a high degree of sequence identity to each other and are likely to have redundant functions. Except for the HMG-box, L-Sox5 and Sox6 have no similarity to Sox9 and, hence, are likely to have a complementary function to that of Sox9. Our experiments suggest the hypothesis that, like Sox9, Sox5 and Sox6 might also be needed for chondrocyte differentiation. Other experiments, have provided evidence that the Sox9 polypeptide and the Sox9 gene are targets of signaling molecules that are known to control discrete steps of chondrogenesis in the growth plate of endochondral bones. Protein kinase A (PKA) phosphorylation of Sox9 increases its DNA binding and transcriptional activity. Since PKA-phosphorylated-Sox9 is found in the prehypertrophic zone of the growth plate, the same location where the gene for the receptor of the parathyroid hormone-related peptide (PTHrP) is expressed and since PTHrP signaling is mediated by cyclic AMP, we have hypothesized that Sox9 is a target for PTHrP signaling. Other experiments have also shown that fibroblast growth factors (FGFs) increase the expression of Sox9 in chondrocytes in culture and that this activation is mediated by the mitogen-activated protein kinase pathway. These results favor the hypothesis that in achondroplasia, a disease caused by activating mutations in FGF receptor 3, there might also be an abnormally high Sox9 expression.

Also flagged:HuntingtinHDHuntington's diseasechromosomes
Journal Article 2000-09-01 ✓ 1 Snippet Pramanik S, Basu P, Gangopadhaya PK, Sinha KK, Jha DK, Sinha S, Das SK, Maity BK, Mukherjee SC, Roychoudhuri S, Majumder PP, Bhattacharyya NP.
In-Text Gene Mentions

We have analysed the distribution of CAG and adjacent polymorphic CCG repeats in the Huntingtin gene in 28 clinically diagnosed unrelated Huntington's disease (HD) patients and in normal individuals belonging to different ethnic groups of India.

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We have analysed the distribution of CAG and adjacent polymorphic CCG repeats in the Huntingtin gene in 28 clinically diagnosed unrelated Huntington's disease (HD) patients and in normal individuals belonging to different ethnic groups of India. The range of expanded CAG repeats in HD patients varied from 41 to 56 repeats, whereas in normal individuals this number varied between 11 and 31 repeats. We identified six CCG alleles from a total of 380 normal chromosomes that were pooled across different ethnic populations of India. There were two predominant alleles: (CCG)7 (72.6%) and (CCG)10 (20%). We report here for the first time one four-repeat CCG allele which has not been found in any population so far. We found 30 haplotypes (two loci CAG-CCG) for 380 normal chromosomes. In the present study, no statistically significant preponderance of expanded HD alleles was found on either (CCG)7 or (CCG)10 backgrounds. Our studies suggest that the overall prevalence of HD in Indian populations may not be as high as in Western populations. Further studies are necessary to identify the origin of HD mutation in these populations.

Also flagged:nucleotidemajor histocompatibility complexchromosomesdlx8PMP22ARHGDIA
Journal Article 2000-09-01 No Snippets Barbazuk WB, Korf I, Kadavi C, Heyen J, Tate S, Wun E, Bedell JA, McPherson JD, Johnson SL.
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The zebrafish is an important vertebrate model for the mutational analysis of genes effecting developmental processes. Understanding the relationship between zebrafish genes and mutations with those of humans will require understanding the syntenic correspondence between the zebrafish and human genomes. High throughput gene and EST mapping projects in zebrafish are now facilitating this goal. Map positions for 523 zebrafish genes and ESTs with predicted human orthologs reveal extensive contiguous blocks of synteny between the zebrafish and human genomes. Eighty percent of genes and ESTs analyzed belong to conserved synteny groups (two or more genes linked in both zebrafish and human) and 56% of all genes analyzed fall in 118 homology segments (uninterrupted segments containing two or more contiguous genes or ESTs with conserved map order between the zebrafish and human genomes). This work now provides a syntenic relationship to the human genome for the majority of the zebrafish genome.

Also flagged:saltBRCA2BRCA1DNA polymeraseBoric acidethylenediaminetetraacetic acid
Journal Article 2000-09-01 No Snippets Tian H, Brody LC, Landers JP.
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In this report, we explore the potential of capillary and microchip electrophoresis for heteroduplex analysis- (HDA) based mutation detection. Fluorescent dye-labeled primers (6-FAM-tagged) were used to amplify the DNA fragments ranging from 130 to 400 bp. The effects of DNA fragment length, matrix additives, pH, and salt were evaluated for capillary electrophoresis- (CE) and/or microchip electrophoresis-based HDA, using six heterozygous mutations, 185delAG, E1250X (3867GT), R1443G (4446CG), 5382insC, 5677insA in BRCA1, and 6174delT in BRCA2. For this system, the effective fragment size for CE-based HDA was found in the range of 200-300 bp, however, the effective range was 150-260 bp for microchip-based HDA. Sensitivity studies show CE-based HDA could detect a mutated DNA present at only 1%-10% of the total DNA. Discrimination between wild-type and deletion or insertion mutations in BRCA1 and BRCA2 with CE-based HDA could be achieved in <8 min, while the substitution mutations required 14 min of analysis time. For each mutation region, 15 samples were run to confirm the accuracy and reproducibility of the method. Using the method described, two previously reported mutations, E1038G (3232AG, missense) and 4427 C/T (4427CT, polymorphism), were detected in the tested samples and confirmed by DNA sequencing. Translation of the CE-based methodology to the microchip format allowed the analysis time for each mutation to be decreased to 130 sec. Based on the results obtained with this model system, it is possible that CE-based HDA methodologies can be developed and used effectively in genetic testing. The fast separation time and automated operation afforded with CE instrumentation provide a powerful system for screening mutations that include small deletions, insertions, and point mutations. Translation to the microchip platform, especially to a multichannel microchip system, would allow for screening mutations with high throughput.

Also flagged:LocalizationironMHC-Class-I-likehereditary haemochromatosisNramp2divalent metal transporter-1
Journal Article 2000-09-01 ✓ 5 Snippets Griffiths WJ, Kelly AL, Smith SJ, Cox TM.
In-Text Gene Mentions

HFE, where it may function to modulate their intrinsic

…recent discovery ofHFE, the MHC-Class-I-like gene…

…Since theHFEprotein can be…

…antisera from humanHFEand DMT-1 derived…

…Disruption of theHFEgene as a…

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The recent discovery of HFE, the MHC-Class-I-like gene mutated in up to 90% of patients with hereditary haemochromatosis, and the gene encoding the Nramp2/divalent metal transporter-1 (DMT-1) implicated in ferrous iron transport holds promise for a greater understanding of human iron metabolism. Since the HFE protein can be crystallized as a ternary complex with the transferrin receptor and iron-saturated transferrin, and DMT-1 expression is up-regulated in hereditary haemochromatosis, these proteins are likely to interact in a common pathway for human iron homeostasis. To investigate the cellular interactions between the cognate proteins encoded by these genes, we generated a panel of rabbit and avian antisera from human HFE and DMT-1 derived peptides. The antibodies were characterized by ELISA reactions and Western immunoblotting. Immunohistochemical staining showed that DMT-1 protein localized to the brush border of human duodenum where it is predicted to serve as the principal transporter of ferrous iron from the intestinal lumen. In the human cell lines, Caco-2 (small intestinal phenotype upon differentiation) and K562 (erythroleukaemic) HFE, in the presence of iron-saturated transferrin, co-localized with transferrin receptors in an early endosome compartment using confocal immunofluorescence microscopy. This interaction may be critical in small-intestinal crypt cells which express HFE, where it may function to modulate their intrinsic iron status thereby programming iron absorption by DMT-1 in the mature enterocyte. In undifferentiated Caco-2 cells, DMT-1 localized to a discrete late endosome compartment distinct from that occupied by HFE where, in addition to brush-border iron uptake, it may function to regulate the availability of iron delivery to intracellular iron pools. Disruption of the HFE gene as a result of mutations associated with hereditary haemochromatosis may thus impair homeostatic mechanisms controlling iron absorption within the small-intestine epithelium by a direct interaction with transferrin receptors and by subsequent alteration of DMT-1 expression. Identification of the molecular interactions of HFE with DMT-1 and other key components of the iron transport pathway has implications for a mechanistic understanding of the pathophysiology of human iron storage diseases as well as the regulation of normal iron balance.

Also flagged:IronWerner's syndromeParkinson's diseasecancergoutrheumatoid arthritis
Journal Article 2000-09-01 ✓ 2 Snippets Johnson S.
In-Text Gene Mentions

…Iron loading inhemochromatosisattains extremely high…

…saturation levels ofhemochromatosis, and it is…

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Iron loading in hemochromatosis attains extremely high levels and is accompanied by many signs (ferritin >300 microg/l, hematocrit >50%, transferrin saturation >70%, etc.). Nevertheless, the disease is often overlooked by physicians, until several organs have been damaged permanently (heart, liver, brain, pancreas, kidneys, spleen, etc.). Therefore, severe oxidative damage catalyzed by Fe could occur, without the extremely high ferritin, hematocrit and transferrin saturation levels of hemochromatosis, and it is unlikely that it would ever be detected or even suspected. I postulate a mechanism, by which a cell can continue to express transferrin receptors, without producing ferritin, even when it is saturated with iron. Furthermore, I suggest that this silent iron loading, induced by cadmium and other metals, plays an important role in many degenerative diseases involving free radicals, DNA damage and peroxynitrite, all of which are intimately linked to iron.Moreover, since ferritin, transferrin saturation and hematocrit levels are not directly related to cellular iron levels, and since excess iron can wreak havoc in the cell, we can conclude that there is a need for a better way to evaluate intracellular iron levels and especially the intracellular free iron levels by a non-invasive technique.Finally, phlebotomy is suggested as the best way to reduce Fe and Mo stores, and chelation with succimer is recommended in order to eliminate Cd.

Also flagged:rheumatoid arthritisRArestriction endonucleasedigestionpathogenesis
Journal Article 2000-09-01 ✓ 4 Snippets Li J, Zhu Y, Singal DP.
In-Text Gene Mentions

HFE gene mutations in patients with rheumatoid arthritis.

<h4>Objective</h4>To investigate the role of C282Y and H63D mutations in HFE gene in susceptibility to rheumatoid arthritis (RA).<h4>Methods</h4>The distribution of C282Y and H63D mutations in patients with RA and in healthy subjects was examined by restriction endonuclease digestion of polymerase chain reaction amplified genomic DNA.<h4>Results</h4>The prevalence of C282Y mutation in patients with RA was the same as in healthy controls.

HFEgene mutations in…

…H63D mutations inHFEgene in susceptibility…

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<h4>Objective</h4>To investigate the role of C282Y and H63D mutations in HFE gene in susceptibility to rheumatoid arthritis (RA).<h4>Methods</h4>The distribution of C282Y and H63D mutations in patients with RA and in healthy subjects was examined by restriction endonuclease digestion of polymerase chain reaction amplified genomic DNA.<h4>Results</h4>The prevalence of C282Y mutation in patients with RA was the same as in healthy controls. In contrast, the distribution of H63D mutation was significantly higher in the total RA patient population and in DRB1 QKRAA/QRRAA epitope positive patients compared to respective groups of controls. Analysis of data showed that (1) both H63D mutation and QKRAA/QRRAA DRB1 epitope are individually associated with RA susceptibility; (2) there is interaction between these 2 factors in development of RA; and (3) both these factors combined have stronger association with RA susceptibility than with these factors individually.<h4>Conclusion</h4>H63D mutation appears to play a role in pathogenesis of RA. This study is small and must be regarded as preliminary. These data therefore need confirmation from independent studies.

Also flagged:deep venous thrombosisactivated protein CAPCantithrombin IIIfactor Varginine
Journal Article 2000-09-01 ✓ 1 Snippet Hingorani A, Ascher E, Yorkovich W, Mazzariol F, Jacob T, Gunduz Y, Salles-Cunha S.
In-Text Gene Mentions

…resistance, antithrombin III (ATIII) level and activity,…

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Although lower extremity deep venous thrombosis (LEDVT) has been associated with a hypercoagulable state, there are scant data available for patients presenting with upper extremity deep venous thrombosis (UEDVT). Therefore, we conducted a prospective study to determine whether such an association exists for UEDVT. Fifty-two patients who presented with UEDVT at our institution from August 1996 to June 1997 underwent a hematological profile consisting of activated protein C (APC) resistance, antithrombin III (ATIII) level and activity, factor V mutation (arginine 506 to glycine), protein C level and activity, protein S level and activity, factors II and X activity, lupus anticoagulant, and cardiolipin antibody. This represented 68% (52/76) of the total number of patients in whom the diagnosis of UEDVT was made by duplex ultrasonography during this time period. The ages ranged from 9 to 97 (mean 63 +/- 23 years). There were 22 males and 30 females. Twenty-five patients (48%) had a central venous line in place, 4 patients (8%) had a pacemaker, 14 patients (27%) had a history of neoplasm, and 7 patients (13%) had concomitant LEDVT. The results of our study showed that a hypercoagulable state may be an underappreciated contributing factor in the development of UEDVT. Contrary to prior belief that three sets of tests are needed to confirm the presence of a hypercoagulable state, these data also suggest that only two tests may be needed.

Also flagged:5-hydroxytryptaminetransporterspulmonary arterial hypertensionSecretiontosecondary pulmonary arterial hypertension
Journal Article 2000-09-01 ✓ 1 Snippet MacLean MR, Herve P, Eddahibi S, Adnot S.
In-Text Gene Mentions

5-HTT

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No abstract available.

Also flagged:galactoseethylene glycoldimethylaminoethylmethacrylatevinyl
Journal Article 2000-09-01 No Snippets Lim DW, Yeom YI, Park TG.
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A block copolymer composed of cationic polymer and poly(ethylene glycol) (PEG) was used as a DNA carrier. Poly(2-(dimethylamino)ethyl methacrylate (DMAEMA)-co-N-vinyl-2-pyrrolidone (NVP)) having a terminal carboxylic group was synthesized by free radical polymerization using an initiator, 4,4'-azobis(4-cyanovaleric acid). The terminal carboxylic acid was activated by N-hydroxysuccinimide (NHS) with dicyclohexylcarbodiimide (DCC) and then conjugated with PEG-bis(amine). For specific gene targeting to asialoglycoprotein receptor of hepatocytes, a galactose moiety was incorporated into the PEG terminal end of poly(DMAEMA-NVP)-b-PEG by reductive coupling using lactose and sodium cyanoborohydride. RSV luciferase plasmid was used as a reporter gene, and in vitro gene transfection efficiency was measured in HepG2 human hepatocarcinoma cells. Poly(DMAEMA-NVP)-b-PEG-galactose/DNA complexes formed at 0.5-2 polymer/plasmid weight ratio had compacted structures around 200 nm particle size and exhibited slightly negative surface charge. These complexes were coated with a cationic, pH sensitive, endosomolytic peptide, KALA, to generate positively charged poly(DMAEMA-NVP)-b-PEG-galactose/DNA/KALA complex particles. In the presence of serum proteins, both the PEG block and the galactose moiety of poly(DMAEMA-NVP)-b-PEG-galactose greatly enhanced the gene transfection efficiency, which was very close to that of Lipofectamine plus. Irrespective of the presence of serum proteins, as the KALA/DNA weight ratio increased, the transfection efficiency of poly(DMAEMA-NVP)-b-PEG-galactose was enhanced due to the pH dependent endosomal disruptive property of KALA. This study demonstrates that sufficient transfection efficiency as high as that of commercial agent could be attained by judicious formulation of molecular engineered poly(DMAEMA-NVP)-b-PEG-galactose in combination with an endosomolytic peptide, KALA.

Also flagged:nucleussemaphorin 3Fnetrin-1axonsantibody
Journal Article 2000-09-01 ✓ 1 Snippet Funato H, Saito-Nakazato Y, Takahashi H.
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…an antibody forDCC.…

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In neural development, major tracts are often formed along the neuromere boundary regions, although the molecular mechanism underlying this formation remains to be clarified. In the diencephalon, axons from the habenular nucleus extend along the neuromere boundary region between p1 and p2. At embryonic days 13-15, among members of class 3 semaphorins, only semaphorin 3F (Sema3F) was expressed in the diencephalon. Sema3F, which was strongly expressed in the rostral p1, repulsed axons from habenular explants. While p2 explants did not exert a repulsive effect on axons from habenular explants at a distance, habenular axons did not grow into p2 explant. Explants from the ventral region of the caudal diencephalon where netrin-1 is expressed attracted the axons from habenular explants. The attractive effect was blocked by an antibody for DCC. These results suggest that the growth of axons from the habenular nucleus along the neuromere boundary region may be regulated by Sema3F from the rostral p1, and netrin-1 from the ventral region of the caudal diencephalon.

Also flagged:membranemetamorphosisbehavioraldendritesdendrite+
Journal Article 2000-09-01 No Snippets Duch C, Levine RB.
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The postembryonic acquisition of behavior requires alterations in neuronal circuitry, which ultimately must be understood as specific changes in neuronal structure, membrane properties, and synaptic connectivity. This study addresses this goal by describing the postembryonic remodeling of the excitability and dendritic morphology of an identified motoneuron, MN5, which during the metamorphosis of Manduca sexta (L.) changes from a slow motoneuron that is involved in larval-crawling behavior into a fast adult flight motoneuron. A fivefold lower input resistance, a higher firing threshold, and an increase in voltage-activated K(+) current contribute to a lower excitability of the adult MN5, which is a prerequisite for its newly acquired behavioral role. In addition, the adult MN5 displays larger Ca(2+) currents. The dendrites of MN5 undergo extensive remodeling. Drastic regression of larval dendrites during early pupal stages is followed by rapid growth of new dendrites. Critical changes in excitability take place during the onset of adult dendrite formation. Larval Ca(2+) currents are absent when dendritic remodeling is most dramatic but increase markedly during later development. Changes in Ca(2+) and K(+) currents follow different time courses, allowing the transient occurrence of Ca(2+) spikes during pupal stages when new dendritic branching ceases. The adult MN5 can produce prolonged Ca(2+) spikes after K(+) currents are reduced. We suggest that alterations in Ca(2+) and K(+) currents are necessary for the participation of MN5 in flight behavior and that the transient production of Ca(2+) spikes may influence postembryonic dendritic remodeling.

Also flagged:SoltbindingSoxleucinecalmodulin-dependent protein kinase IV
Journal Article 2000-09-01 ✓ 5 Snippets Yamashita A, Ito M, Takamatsu N, Shiba T.
In-Text Gene Mentions

…Solt, a novel SoxLZ/Sox6binding protein expressed…

…SoxLZ/Sox6, a member of…

…identified a novel SoxLZ/Sox6binding protein, termed…

…Like SoxLZ/Sox6mRNA, Solt mRNA…

…zipper region of SoxLZ/Sox6in vitro.…

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SoxLZ/Sox6, a member of the Sox protein family, contains a leucine zipper motif in addition to an HMG box, which is its DNA binding domain. Here we have identified a novel SoxLZ/Sox6 binding protein, termed Solt, which we obtained independently using both a far-Western blot and a yeast two-hybrid screen. Like SoxLZ/Sox6 mRNA, Solt mRNA was exclusively expressed in the testis in mouse. Solt contains an unusual leucine zipper, which bound to the leucine zipper region of SoxLZ/Sox6 in vitro. In transient transfection assays in CHO cells with SoxLZ/Sox6 containing the transactivational region of herpes simplex virus VP16, expression of a reporter gene that carries a cis binding region for Sox proteins was significantly enhanced by the co-expression of Solt and Ca(2+)/calmodulin-dependent protein kinase IV.

Also flagged:acute myeloid leukaemiagranulocytic sarcomaMLLAF10chromosomeschromosome
Journal Article 2000-09-01 No Snippets Lillington DM, Jaju RJ, Shankar AG, Neat M, Kearney L, Young BD, Saha V.
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A diagnosis of granulocytic sarcoma was made in a 2-year-old child based on the detection of myelomonocytic blasts in tissue obtained from a subcutaneous nodule with no evidence of concomitant disease in the bone marrow. The child responded to systemic chemotherapy and is in remission 3 years later. An identical clone with an in frame fusion of the MLL and AF10 genes was identified from both tissue and bone marrow samples. The generation of an in frame MLL-AF10 fusion requires complex intra- and interchromosomal exchanges between chromosomes 10 and 11. In this case, an intrachromosomal rearrangement of chromosome 5 was also observed. This case illustrates the presence of systemic disease in extramedullary leukaemia, its response to systemic rather than topical therapy and suggests that the events leading to chromosomal translocations in leukaemia may be part of a generalized intracellular event.

Also flagged:hereditary hemochromatosisliver diseasediabetesheart diseaseironpathogenesis
Journal Article 2000-09-01 ✓ 5 Snippets Adams PC.
In-Text Gene Mentions

Genetic testing for the C282Y mutation of the HFE gene has been a major advance in the diagnosis of hereditary hemochromatosis.

…homozygotes for C282Yhemochromatosis: minority or majority…

…mutation of theHFEgene has been…

…90% of typicalhemochromatosispatients are homozygous…

…clinical diagnosis ofhemochromatosisand mortality from…

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Genetic testing for the C282Y mutation of the HFE gene has been a major advance in the diagnosis of hereditary hemochromatosis. In most studies, more than 90% of typical hemochromatosis patients are homozygous for the C282Y mutation. Large-scale population screening studies in predominantly Caucasian populations have demonstrated a high prevalence of C282Y homozygotes of approximately 1 in 300. Despite this high prevalence by genetic testing, the clinical diagnosis of hemochromatosis and mortality from the disease are much less common. One possibility is the presence of many undiagnosed cases with nonspecific symptoms, and deaths occurring that are attributed to liver disease, diabetes, and heart disease without the recognition of iron overload secondary to hemochromatosis. Another possibility is a high prevalence of nonexpressing homozygotes. In this review, the available data on nonexpressing C282Y homozygotes is collected including information on pathogenesis, environmental interactions, and implications for population screening using genetic testing.

Also flagged:oxygenintraventricular hemorrhagepatent ductus arteriosusalbuminMBPhyperbilirubinemia
Journal Article 2000-09-01 No Snippets Ibrahim HM, Krouskop RW, Lewis DF, Dhanireddy R.
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<h4>Objective</h4>To investigate the clinical effects of early versus late cord clamping in preterm infants.<h4>Study design</h4>A total of 32 premature infants were prospectively randomized. The following parameters were measured: Initial spun hematocrit (Hct), hemoglobin (Hgb), red blood cell (RBC) counts, frequency of blood transfusions, peak serum bilirubin, mean blood pressure (MBP), oxygen index, intraventricular hemorrhage, and significant patent ductus arteriosus (PDA).<h4>Results</h4>Over the 4-week study period, the delayed cord clamping (DCC) group exhibited a decrease in the frequency of blood transfusion (p < 0.001) and also a decrease in albumin transfusions over the first 24 hours (p < 0.03). MBP in the first 4 hours was higher in the DCC group (p < 0.01), and there were statistically significant increases in Hct (21%), Hgb (23%), and RBC count (21%) compared with the early cord clamping group. The risks of patent ductus arteriosus, hyperbilirubinemia, or intraventricular hemorrhage were similar in both groups. Late clamping of the umbilical cord had little or no effect on the oxygen index.<h4>Conclusion</h4>DCC significantly reduced the requirement for blood and albumin transfusion. It also increased the initial Hct, RBC count, Hgb levels, and MBP.

Also flagged:heparansulfateantithrombin IIIheparan sulfate glycosaminoglycan3-O-sulfotransferase isoform 13-OST-1
Journal Article 2000-09-01 ✓ 3 Snippets Hernaiz M, Liu J, Rosenberg RD, Linhardt RJ.
In-Text Gene Mentions

…with antithrombin III (ATIII) when it was…

ATIIIbound tightly with…

…affinity binding toATIII.…

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A heparan sulfate glycosaminoglycan chain, biotinylated at its reducing-end, was bound to a streptavidin-coated biochip. Surface plasmon resonance spectroscopy showed a low affinity interaction with antithrombin III (ATIII) when it was flowed over a surface containing heparan sulfate. ATIII bound tightly with high affinity when the same surface was enzymatically modified to using 3-O-sulfotransferase isoform 1 (3-OST-1) in the presence of 3'-phosphoadenosine 5'-phosphosulfate (PAPS). The 3-OST-1 enzyme is involved in heparan sulfate biosynthesis and introduces a critical 3-O-sulfo group into this glycosaminoglycan affording the appropriate pentasaccharide sequence capable of high affinity binding to ATIII. This experiment demonstrates the specific structural modification of a glycosaminoglycan bound to a biochip using a biosynthetic enzyme, suggesting a new approach to rapid screening glycosaminoglycan-protein interactions.

Also flagged:diabetes mellitusGenetic HemochromatosisGHcirrhosis
Journal Article 2000-09-01 ✓ 3 Snippets Dubois-Laforgue D, Larger E, Timsit J.
In-Text Gene Mentions

…condition to suspecthemochromatosis?].…

…poor predictor ofhemochromatosis.…

…the search forhemochromatosismust be performed…

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Genetic Hemochromatosis (GH) is a highly prevalent autosomal recessive disorder, which outcome has been dramatically improved by early phlebotomy. Attempts to screen for the disease, using biological and genetic approaches, are currently under evaluation. Diabetes mellitus often complicates GH. However, as it occurs late in the course of the disease, in most cases when cirrhosis is already present, its usefulness for the screening of GH seems reduced. Diabetes mellitus, when isolated, appears also as a poor predictor of hemochromatosis. Indeed, the risk of being carrier of the disease is not increased in diabetic patients compared with non diabetic sujects. This risk is however highly enhanced by the co-existence of cirrhosis. Thus, in the face of a newly diagnosed diabetes mellitus, the search for hemochromatosis must be performed only when it associates with cirrhosis or with other evocative clinical conditions.

Also flagged:antibodyGenetic hemochromatosisGHironmetabolismHLA-Aw68
Journal Article 2000-09-01 ✓ 5 Snippets Dupradeau F, Altenberg-Greulich B, Warin R, Fuentes V, Monti J, Rochette J.
In-Text Gene Mentions

Structural studies of the protein product of the HFE gene are of major interest for a better understanding of the molecular physiopathology in iron overload.

…homology of theHFEprotein: molecular consequence…

…for GH, namelyHFEhas been recently…

…product of theHFEgene are of…

…biological activity ofHFE.…

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Genetic hemochromatosis (GH) is a common inherited disease of iron metabolism affecting 2-5 in 1000 individuals of European origin. A candidate gene for GH, namely HFE has been recently characterized. Structural studies of the protein product of the HFE gene are of major interest for a better understanding of the molecular physiopathology in iron overload. We have built a 3-dimensional model of the HFE protein based on congruent with40% homology of sequence identity with HLA-Aw68, another MHC class I molecule. This work presents the first 3-dimensional structure of HFE available in the public domain (http://swift.embl-heidelberg.de/service/francois). The 3-dimensional characteristics of the protein complexed with the beta2-microglobulin are presented. The model has been used to predict immunogenic loops and to develop an antibody able to recognize a protein exhibiting the same molecular weight as HFE. Structural consequences of two common mutations are debated and evolutionary hypotheses are considered in the discussion of the particular biological activity of HFE. This study shows that a strategy based on homology modeling is sufficient to undertake biological investigations.

Also flagged:synthesispeptideRas CaaX endoproteaseacetyltetrapeptidesRas
Journal Article 2000-09-01 No Snippets Dolence EK, Dolence JM, Poulter CD.
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A solid-phase method, based on Kaiser's p-benzophenone oxime resin, was developed for the synthesis of a series of N-acetyl-S-(E, E-farnesylated) Ca(1)a(2)X tetrapeptides as potential inhibitors of recombinant Ras and a-factor converting enzyme (RCE). N-Acetyl-S-(E, E-farnesyl)-L-cysteine was coupled to resin-bound a(1)a(2) dipeptide using HOBt/DCC activation in conjunction with N-BOC chemistry. The protected farnesylated tripeptide was cleaved from the resin with simultaneous addition of the X residue by treating the resin-bound farnesylated Ca(1)a(2) tripeptide with L-amino acid benzyl ester tosylates under mildly acidic conditions. The benzyl ester was saponified, and the resulting carboxylate precipitated by ether to afford a library of tetrapeptides as a mixture of diastereomers at the cysteine center. The peptides were evaluated as inhibitors of recombinant yeast RCE endoprotease (yRCE) to obtain information about the affinity of the enzyme for the a(1)a(2)X portion of the Ca(1)a(2)X moiety.

Also flagged:infectionporphyria cutanea tardapathogenesisHCV infection
Journal Article 2000-09-01 ✓ 5 Snippets Nagy Z, Kószó F, Pár A, Nagy A, Horányi M, Morvay M, Dobozy A, Mózsik G.
In-Text Gene Mentions

HFE) gene mutation and hepatitis C

HFE) and hepatitis C

HFE) gene mutation and hepatitis C virus (HCV) infection risk factors for porphyria cutanea tarda

HFE) and hepatitis C virus (HCV) act independently in the pathogenesis of porphyria cutanea tarda (PCT

HFE gene were determined in 19 PCT

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As it is not clear whether mutations in hemochromatosis gene (HFE) and hepatitis C virus (HCV) act independently in the pathogenesis of porphyria cutanea tarda (PCT), and prevalence of both risk factors reveals a great variety in different parts of the world, PCT patients from our Central East European country were investigated for this aspect. The occurrence of the C282Y and H63D mutations in HFE gene were determined in 19 PCT patients and compared with the reported control frequencies. Furthermore, the presence of HCV infection was determined and related to the patients' HFE status. The C282Y mutation was found in 3/19 cases (one patient was homozygous and two heterozygous), with an 10.5% allele frequency (vs. 3.8% control) (p < 0.05). Five patients were heterozygous for the H63D mutation, allele frequency 13.1%, which did not differ from the reported control prevalence of 12.3%. Six patients (31.7%) were HCV-RNA positive, out of the six one was heterozygous for H63D mutation and one was compound heterozygous. HCV infection and HFE C282Y mutations may probably be independent predisposing factors for development of PCT in Hungarian patients.

Also flagged:phorbolacetateHuntingtinSp1phorbol esterHuntington's disease
Journal Article 2000-09-01 No Snippets Coles R, Birdsall M, Wyttenbach A, Rubinsztein DC.
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We have studied the effects of the phorbol ester, 12-O-tetradecanoyl-phorbol-13-acetate (TPA) on Huntington's disease (HD) gene transcription in neuronal and non-neuronal cell lines, to investigate pathways regulating HD gene expression. TPA reduced transcription from the HD gene promoter in SK-N-SH (neuroblastoma) and HeLa cells but not in JEG3 (choriocarcinoma) cells. In SK-N-SH cells, the responsible cis-acting promoter sequences comprise the tandemly duplicated Sp1 sites in the region from -213 to -174, relative to the translation start site. The TPA-down-regulating region in HeLa cells was mapped to the sequence from -141 to -126. In conclusion, this demonstrates that HD gene transcription can be down-regulated in vitro in a cell-specific manner.

Also flagged:cytosoloestrogen receptorinvasive breast cancerERbreast cancerdextran
Journal Article 2000-09-01 ✓ 1 Snippet Gordts SL, Neven P, Van Hooff I, Tonglet R, Laurent C, Marechal S, De Muylder X, Van Belle Y, Vanderick G.
In-Text Gene Mentions

…between ICA andDCCfor ER measurement…

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To compare two methods of measurement of oestrogen receptor (ER)-expression in invasive breast cancer tissue. Sections from 299 breast cancer cases were stained for the ER by immunocytochemical assay (ICA), using mouse monoclonal antibody (MAb) NCL-ER-6SF11, and by the dextran-coated charcoal assay (DCC). Concordant results were observed in 230 of the 299 cases (77%), 69 patients had discordant results (kappa=0.537). We found a moderate concordance between ICA and DCC for ER measurement in breast cancer tissue. If we change the golden standard from DCC to ICA, 23% of patients would receive a different therapeutic approach.

Also flagged:prothrombinobesityinsulintriglyceridesPAI-1fibrinogen
Journal Article 2000-09-01 ✓ 1 Snippet Połać I, Stachowiak G, Jedrzejczyk S, Pertyński T, Sobczuk A, Pakalski A, Stetkiewicz T, Owczarek D.
In-Text Gene Mentions

…vWf and lowerATIII.…

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<h4>Objectives</h4>Objective was to examine the relationship of obesity, body fat distribution fasting plasma insulin concentrations and triglycerides of pro-thrombotic and fibrinolitics factors in pre and postmenopausal women.<h4>Material and methods</h4>We assessed 24 (13 nonobese and 11 obese) postmenopausal and 44 (15 obese and 29 non obese) premenopausal women. Plasma concentration of PAI-1 ag,PAI-1 activity, fibrinogen, tPA-1 akt, tPA ag, von Willebrand factor, fasting plasma insulin, and the lipid pattern (cholesterol, TG, HDL, LDL) was measured. The body fat distribution was assessed by waist-to-hip circumference measuring.<h4>Results</h4>Postmenopausal subjects had higher PAI-1 act. and PAI-1 ag (p < 0.05 and 0.001 respectively), vWf and lower ATIII. There was direct correlation between PAI-1 act., Fibrinogen and BMI in both groups of patients together and in premenopausal group PAI-1 act correlated directly and tPA ag/act. indirectly with plasma insulin concentrations.<h4>Conclusions</h4>Plasma concentrations of the pro-thrombotic factors are increased in obese and postmenopausal women and correlate directly with BMI and indirectly with plasma insulin concentrations. Plasma concentrations of anti thrombotic factors indirectly correlated with WHR and with plasma insulin concentrations.

Also flagged:bleeding disorderrenal failureanemialeucocytosisfibrinogenfactor V
Journal Article 2000-09-01 ✓ 1 Snippet Arocha-Piñango CL, Marval E, Guerrero B.
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…levels with normalATIIIand platelets.…

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In 1967 we reported for the first time five cases of an acquired bleeding disorder in humans which developed after contact with saturnidae caterpillars. Since that time, other cases have been reported in Brazil, French Guyana, Peru, Paraguay and Argentina. The caterpillars have been identified as Lonomia achelous (LA) in Venezuela and northern Brazil and as Lonomia obliqua (LO) in southern Brazil. All patients present pain and a burning sensation at the site of contact. Within a few hours hematomas and hematuria are seen in combination with intracerebral and intraperitoneal hemorrhage (in some cases also renal failure). Hematological tests show: mild anemia with leucocytosis; prolonged PT, PTT and ThT; decreased fibrinogen, factor V, factor XIII, plasminogen and alpha2-antiplasmin levels; increased factor VIII:c, von Willebrand factor, and FDPs/D-dimers levels with normal ATIII and platelets. Factor VII, factor II and PC levels varied. Several activities similar to or directed against blood clotting factors have been identified in LA: fibrinolytic enzymes, which degrade fibrinogen producing abnormal FDPs; prothrombin activators: one direct and one factor Xa-like; a thermostable factor V activator; a thermolabile factor V inhibitor; a factor XIII proteolytic/urokinase-like activity; and a kallikrein-like activitiy. In LO three activities have been described: a prothrombin activator called 'Lonomia obliqua prothrombin activator protease' (LOPAP); a factor X activator; and a phospholipase A(2)-like activity called Lonomiatoxin. No fibrinolytic activity has been described in LO. Subcutaneous injection of crude hemolymph and some chromatographic fractions of LA induce a decrease in fibrinogen, plasminogen and factor XIII. Intravenous injection of factor XIII proteolytic/urokinase-like activity induce a dose-dependent thrombolysis with a decrease in plasmatic factor XIII without hemorrhagic manifestations. Intradermal injection of LO bristle extracts in rats and rabbits produce incoagulability whereas intravenous injection of LOPAP induced DIC in mice.

Also flagged:vitamin-Eclottingheparinmembranescelluloseprothrombin
Journal Article 2000-09-01 ✓ 2 Snippets Huraib S, Tanimu D, Shaheen F, Hejaili F, Giles C, Pagayon V.
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…S, antithrombin III (ATIII) and factor 12…

…protein S andATIII.…

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We performed a crossover study to compare the effects of different dialysis membranes on 20 patients with frequent dialyser clotting and requiring > or = 5,000 units of heparin per dialysis session. Low-flux dialysers are C15NL (cellulose - Terumo) and E15NL (vitamin-E-coated - Terumo) while high-flux dialysers were F60 (polysulphone) and EE15NL (vitamin-E-coated - Terumo). Ten patients underwent dialysis for 2 months with C15NL then switched to E15NL for 2 months. Similarly, the other 10 patients were started on the high-flux dialyser F60 and then switched over to EE15NL for 2 months. The following parameters were measured at the beginning of the study, 2 weeks, 1 month and then at 2 months: hemoglobin, prothrombin time (PT), partial thromboplastin time (PTT), fibrinogen, protein C, protein S, antithrombin III (ATIII) and factor 12 activity. Dialyser clotting, heparin and erythropoietin requirements were assessed during each dialysis session. There was a significant reduction in clotting with E15NL in comparison to C15NL (22.8 +/- 17 and 44.1 +/- 22.8 (p = 0.0233), respectively). Similarly, heparin requirements were less in the vitamin-E-coated (E15NL) dialysers, 4, 754 +/- 1,427 vs. 6,011 +/- 856 units (p = 0.0281) and erythropoietin usage was also significantly reduced, 4,630 +/- 2,620 vs. 7,850 +/- 4,069 units (p = 0.049). There was a significant increase in hemoglobin with E15NL compared to C15NL, 115 +/- 10.4 vs. 108 +/- 13.1 (p = 0.0343). When the high-flux dialysers were compared there was a tendency towards less dialyser clotting with the EE15NL compared to F60, though this did not achieve statistical significance (p = 0.0561). We could not demonstrate any significant changes between the different dialysers with regards to PT, PTT, fibrinogen factor 12 activity, protein C, protein S and ATIII. In conclusion, we have shown that the use of vitamin-E-modified dialysers is associated with less clotting in patients with persistent clotting problems. In addition, this was associated with less heparin and erythropoietin requirements.

Also flagged:NGFFGF-2IT15Huntington's diseaseHDbasic fibroblast growth factor
Journal Article 2000-09-01 No Snippets Haque NS, Isacson O.
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A mutation of the human IT15 gene is responsible for Huntington's disease (HD) and the causative factor in the major neuronal loss observed in the striatum. The growth factors basic fibroblast growth factor (FGF-2), nerve growth factor (NGF), and brain-derived neurotrophic factor (BDNF) improve survival and promote differentiation of striatal neurons, as well as exert a neuroprotective effect when such neurons are challenged with metabolic toxins or excitatory amino acids. Using Western blotting and striatal cell cultures, we found that FGF-2 increased the level of huntingtin in a dose-dependent fashion, whereas NGF decreased huntingtin expression. The neurotrophic factor-specific, dose-dependent effect on striatal levels of huntingtin may be relevant to understanding the normal role of IT15 and developing new therapies against the disease provoking mutated IT15.

Also flagged:Deep-vein thrombosisDVTpulmonary embolismPEgallstonesAntitrombin III
Journal Article 2000-09-01 ✓ 2 Snippets Di Vita G, Sciumè C, Lauria Lauria G, Stella C, Raimondo D, Leo P.
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…Antitrombin III (ATIII), fibrinogen degradation prod…

….<h4>Results</h4>The levels ofATIIIdid not present…

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<h4>Background</h4>Deep-vein thrombosis (DVT) and pulmonary embolism (PE) are the most important causes of morbility and mortality in patients submitted to surgical intervention: some peculiar factors of laparoscopic surgery can modify their risk. The aim of this study is to evaluate possible variations of the fibrinolytic system after cholecystectomy.<h4>Methods</h4>Eighteen patients affected by symptomatic and non-complicated gallstones have been included in this study. They were divided into two groups of nine patients each: the first group was submitted to laparoscopic cholecystectomy (LC) and the second to open cholecystectomy (OC). Antitrombin III (ATIII), fibrinogen degradation products (FDP), tissue plasminogen activator (tPA), and plasminogen activator inhibitor (PAI) have been evaluated preoperatively and 6, 12, 24 and 48 hours after the operation.<h4>Results</h4>The levels of ATIII did not present significantly variations. The FDP in both groups were significantly increased 48 hours after open cholecystectomy. Levels of PAI instead were increased in comparison to the basal values at 6, 12, 24, 48 hours with p < 0.05; p < 0.01 and p < 0.05 respectively in patients submitted to OC, in the LC group no variations were observed; a comparison between the groups showed a significant modification (p < 0.05) only at the 12th hour.<h4>Conclusions</h4>The early mobilization of patients in the postoperative course and the lower invasion of LC can oppose the prothrombotic effect in the lower limbs.

Also flagged:tryptophan hydroxylaseaggressionschizophreniaschizoaffective disorderserotonin transporterTPH
Journal Article 2000-09-01 ✓ 3 Snippets Nolan KA, Volavka J, Lachman HM, Saito T.
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Polymorphisms in the regulatory region of the serotonin transporter (5-HTT), in intron 7 of the tryptophan hydroxylase (TPH) gene and in the MAOA gene were previously reported to be associated with mood and anxiety disorders, impulsivity and aggression.

…the serotonin transporter (5-HTT), in intron 7…

…for either the5-HTTor MAOA polymorphisms…

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Serotonergic pathways have been implicated in impulsive and aggressive behavior. Polymorphisms in the regulatory region of the serotonin transporter (5-HTT), in intron 7 of the tryptophan hydroxylase (TPH) gene and in the MAOA gene were previously reported to be associated with mood and anxiety disorders, impulsivity and aggression. In this study, we analyzed these polymorphisms in men and women with schizophrenia or schizoaffective disorder (n = 84) who met our criteria for violence (history of two or more assaults on others) or nonviolence (no history of either assaultive or threatening behavior). In males, a modest association between TPH genotype and history of violence (chi-square test = 6.703, degrees of freedom = 2, P = 0.035) was not statistically significant after correction for multiple comparisons (corrected P = 0.21). The TPH L allele was more frequent in violent males (chi-square = 5.323, degrees of freedom = 1, P = 0.021) but this difference also failed to withstand correction (corrected P = 0.126). No significant associations were found for either the 5-HTT or MAOA polymorphisms in males or females. These results tend to support previous reports by New et al. (1996; 1998) of an association between the TPH L allele and impulsive aggression in males with personality disorder, but larger studies are needed.

Also flagged:BRCA1ovarian cancersMDM2p53breast cancerovarian cancer
Journal Article 2000-09-01 ✓ 1 Snippet Nadeau G, Boufaied N, Moisan A, Lemieux KM, Cayanan C, Monteiro AN, Gaudreau L.
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ABT1

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Most familial breast and ovarian cancers have been linked to mutations in the BRCA1 gene. BRCA1 has been shown to affect gene transcription but how it does so remains elusive. Here we show that BRCA1 can stimulate transcription without the requirement for a DNA-tethering function in mammalian and yeast cells. Furthermore, the BRCA1 C-terminal region can stimulate transcription of the p53-responsive promoter, MDM2. Unlike many enhancer-specific activators, non-tethered BRCA1 does not require a functional TATA element to stimulate transcription. Our results suggest that BRCA1 can enhance transcription by a function additional to recruiting the transcriptional machinery to a targeted gene.

Also flagged:psychiatric disordersdiphtheriabrain dysfunctionobsessive-compulsive disorderdepressionpsychiatric illness
Journal Article 2000-09-01 ✓ 1 Snippet Schulz P, Steimer T.
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On the other hand, there are psychotropic drugs with a more selective mode of action, for example, the serotonin (5-HT) transporter (5-HTT) blockers (selective serotonin reuptake inhibitors [SSRIs]).

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Conventional psychiatric diagnosis is founded on symptom description; this then governs the choice of psychotropic medication. This purely descriptive approach resembles a description of diphtheria from the premicrobiology era. Based on current advances in basic and clinical neuroscience, we propose inserting an intermediate level of analysis between psychiatric symptoms and pharmacologic modes of action. Paradigm 1 is to analyze psychiatric symptoms in terms of which higher brain function(s) is (are) abnormal, ie, symptoms should be analyzed as higher brain dysfunction: a case study in obsessive-compulsive disorder reveals pointers in four common symptoms to the higher functions of working memory, emotional overlay, absence of voluntary control, and the ability to evaluate personal mental phenomena. Paradigm 2 is to view psychotropic drugs as modifying normal higher brain functions, rather than merely treating symptoms, which they do only secondarily: thus depression may respond to agents that act on related aspects of mental life derived from higher brain functions, eg, the ability to enhance bonding. We advocate a strategy in which psychiatric illness is progressively reclassified through knowledge in clinical neuroscience and treatment targets are revised accordingly.