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Viewing May 2001 — 53 paper(s) from the local store. (Local view only — run without --view to fetch new papers.)
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Also flagged:ironFerritinSynthesisiron regulatory proteinIRPL-ferritin
Journal Article 2001-05-24 No Snippets Kato J, Fujikawa K, Kanda M, Fukuda N, Sasaki K, Takayama T, Kobune M, Takada K, Takimoto R, Hamada H, Ikeda T, Niitsu Y.
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Ferritin, which is composed of H and L subunits, plays an important role in iron storage and in the control of intracellular iron distribution. Synthesis of both ferritin subunits is controlled by a common cytosolic protein, iron regulatory protein (IRP), which binds to the iron-responsive element (IRE) in the 5'-UTR of the H- and L-ferritin mRNAs. In the present study, we have identified a single point mutation (A49U) in the IRE motif of H-ferritin mRNA, in four of seven members of a Japanese family affected by dominantly inherited iron overload. Gel-shift mobility assay and Scatchard-plot analysis revealed that a mutated IRE probe had a higher binding affinity to IRP than did the wild-type probe. When mutated H subunit was overexpressed in COS-1 cells, suppression of H-subunit synthesis and of the increment of radiolabeled iron uptake were observed. These data suggest that the A49U mutation in the IRE of H-subunit is responsible for tissue iron deposition and is a novel cause of hereditary iron overload, most likely related to impairment of the ferroxidase activity generated by H subunit.

Also flagged:Sox9campomelic dysplasiapathogenesisCol2a1mineralizationorganization
Journal Article 2001-05-22 ✓ 1 Snippet Bi W, Huang W, Whitworth DJ, Deng JM, Zhang Z, Behringer RR, de Crombrugghe B.
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Sox6

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In humans, SOX9 heterozygous mutations cause the severe skeletal dysmorphology syndrome campomelic dysplasia. Except for clinical descriptions, little is known about the pathogenesis of this disease. We have generated heterozygous Sox9 mutant mice that phenocopy most of the skeletal abnormalities of this syndrome. The Sox9(+/-) mice died perinatally with cleft palate, as well as hypoplasia and bending of many skeletal structures derived from cartilage precursors. In embryonic day (E)14.5 heterozygous embryos, bending of radius, ulna, and tibia cartilages was already prominent. In E12.5 heterozygotes, all skeletal elements visualized by using Alcian blue were smaller. In addition, the overall levels of Col2a1 RNA at E10.5 and E12.5 were lower than in wild-type embryos. We propose that the skeletal abnormalities observed at later embryonic stages were caused by delayed or defective precartilaginous condensations. Furthermore, in E18.5 embryos and in newborn heterozygotes, premature mineralization occurred in many bones, including vertebrae and some craniofacial bones. Because Sox9 is not expressed in the mineralized portion of the growth plate, this premature mineralization is very likely the consequence of allele insufficiency existing in cells of the growth plate that express Sox9. Because the hypertrophic zone of the heterozygous Sox9 mutants was larger than that of wild-type mice, we propose that Sox9 also has a role in regulating the transition to hypertrophic chondrocytes in the growth plate. Despite the severe hypoplasia of cartilages, the overall organization and cellular composition of the growth plate were otherwise normal. Our results suggest the hypothesis that two critical steps of the chondrocyte differentiation pathway are sensitive to Sox9 dosage. First, an early step presumably at the stage of mesenchymal condensation of cartilage primordia, and second, a later step preceding the transition of chondrocytes into hypertrophic chondrocytes.

Also flagged:gene expressionserine/threonine protein kinaseinfectionB1kinaseRNA polymerase
Journal Article 2001-05-01 ✓ 1 Snippet Kovacs GR, Vasilakis N, Moss B.
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VRK2

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The B1 gene of vaccinia virus encodes a serine/threonine protein kinase that is expressed early after infection. Under nonpermissive conditions, temperature-sensitive mutants (ts2 and ts25) that map to B1 fail to efficiently replicate viral DNA. Our goal was to extend studies on the function of B1 by determining if the kinase is required for intermediate or late gene expression, two events that ordinarily depend on viral DNA replication. First, we established that early viral gene expression occurred at the nonpermissive temperature. By using a transfection procedure that circumvents the viral DNA replication requirement, we found that reporter genes regulated by an intermediate promoter were transcribed only under conditions permissive for expression of active B1. To assay late gene expression, the T7 RNA polymerase gene was inserted into the genome of ts25 to form ts25/T7. A DNA replication-independent late gene transcription system was established by cotransfecting plasmids containing T7 promoter-driven late gene transcription factors and a late promoter reporter gene into ts25/T7-infected cells. Late genes, unlike intermediate genes, were expressed at the nonpermissive temperature. Last, we showed that overexpression of B1 stimulated intermediate but inhibited late gene expression in cells infected with wild-type virus.

Also flagged:CAShepatitisliver neoplasmstumorRan-binding proteinnuclear
Journal Article 2001-05-01 ✓ 4 Snippets Wellmann A, Flemming P, Behrens P, Wuppermann K, Lang H, Oldhafer K, Pastan I, Brinkmann U.
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High expression of the proliferation and apoptosis associated CSE1L/CAS gene in hepatitis and liver neoplasms: correlation with tumor progression.

…and apoptosis associatedCSE1L/CAS gene in hepatitis…

…TheCSE1L/CAS protein (CAS) is…

…other ran-binding proteins,CSE1L/CAS simultaneously plays a…

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The CSE1L/CAS protein (CAS) is a Ran-binding protein with a function as nuclear transport (export) factor. Like recently observed for ran and other ran-binding proteins, CSE1L/CAS simultaneously plays a role in the mitotic spindle checkpoint, which assures genomic stability during cell division. This checkpoint is frequently disturbed in neoplasias of various origin, including hepatic tumors. We have evaluated by immunohistology the expression of CAS in adult and embryonic liver, hepatitis, and in liver hyperplasias. Normal hepatocytes revealed no CAS expression while embryonic liver showed strong expression in all parenchymal cells. Bile ducts stained positive with anti-CAS antibodies, and strong CAS expression was also detected at the interface between bile ducts and hepatocytes under conditions associated with regenerative proliferation. The localization of these CAS expressing cells correlated with the distribution of putative liver stem-cells. In active viral (but not in inactive) hepatitis, strong hepatocytal CAS expression correlates in site and intensity with degree of inflammation. Neoplastic liver demonstrated different degrees of CAS expression: no remarkable expression in adenomas, moderate expression in a narrow rim of hepatocytes and in periseptal cholangiolar proliferations in focal nodular hyperplasia, and strong CAS expression in hepatocellular carcinoma. Less differentiated tumors stain stronger than well differentiated. Cholangio-cellular carcinomas show even stronger CAS expression than hepatocellular carcinomas. Our observation of strong expression of CAS in liver cells that are committed for proliferation among them possibly liver stem cells, and in liver neoplasms, is consistant with the fact that CAS functions not solely as a nuclear transport factor but that it is also essential for cell proliferation, particularly for the mitotic spindle checkpoint. Interestingly, genomic instability is frequently observed in hepatic tumors which we have shown here to express large amounts of CAS. Since the degree of CAS-expression correlates with the grade of tumor dedifferentiation, we suggest that CAS should also be further investigated as prognostic marker for hepatic neoplasms.

Also flagged:meningiomasMADH2MADH4APM-1tumorchromosome
Journal Article 2001-05-01 ✓ 5 Snippets Büschges R, Boström J, Wolter M, Blaschke B, Weber RG, Lichter P, Collins VP, Reifenberger G.
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Taken together, our data do not support a significant role for MADH2, MADH4, APM-1 and DCC alterations in the pathogenesis of meningiomas.

In the present study, we have investigated a series of 37 meningiomas for mutation and expression of 4 tumor suppressor genes (MADH2, MADH4, APM-1 and DCC) located at 18q21.

MADH2, MADH4, APM-1 and DCC tumor

DCC tumor

tumor suppressor genes (MADH2, MADH4, APM-1 and DCC

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We have previously reported that losses of genomic material from the long arm of chromosome 18 are frequent in atypical and anaplastic meningiomas but rare in benign meningiomas. In the present study, we have investigated a series of 37 meningiomas for mutation and expression of 4 tumor suppressor genes (MADH2, MADH4, APM-1 and DCC) located at 18q21. Comparative genomic hybridization or loss of heterozygosity analysis showed losses on chromosome 18 that included sequences from 18q21 in 15 of 37 tumors. Mutation analysis of APM-1 revealed a missense mutation (c. 1819G>A: G607S) in 1 atypical meningioma. None of the tumors showed mutations of MADH2 and MADH4 or loss of detectable transcripts from MADH2, MADH4, APM-1 and DCC. In contrast to human brain tissue, normal leptomeninges and meningiomas showed preferential expression of a DCC splice variant lacking 60 base pairs from exon 17. Taken together, our data do not support a significant role for MADH2, MADH4, APM-1 and DCC alterations in the pathogenesis of meningiomas. The targeted gene that is inactivated in most meningiomas with 18q losses remains to be identified.

Also flagged:localizationBM88chromosomeBeckwith-Wiedemann syndromeneuroblastomacell differentiation
Journal Article 2001-05-01 No Snippets Gaitanou M, Buanne P, Pappa C, Georgopoulou N, Mamalaki A, Tirone F, Matsas R.
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Porcine BM88 is a neuron-specific protein that enhances neuroblastoma cell differentiation in vitro and may be involved in neuronal differentiation in vivo. Here we report the identification, by Western blotting, of homologous proteins in human and mouse brain and the isolation of their respective cDNAs. Several human and mouse clones were identified in the EST database using porcine BM88 cDNA as a query. A human and a mouse EST clone were chosen for sequencing and were found both to predict a protein of 149 amino acids, with 79.9% reciprocal identity, and 76.4% and 70.7% identities to the porcine protein, respectively. This indicated that the clones corresponded to the human and mouse BM88 homologues. In vitro expression in a cell-free system as well as transient expression in COS7 cells yielded polypeptide products that were recognized by anti-BM88 antibodies and were identical in size to the native BM88 protein. Northern-blot analysis showed a wide distribution of the gene in human brain whereas immunohistochemistry on human brain sections demonstrated that the expression of BM88 is confined to neurons. The initial mapping assignment of human BM88 to chromosome 11p15.5, a region implicated in Beckwith-Wiedemann syndrome and tumorigenesis, was retrieved from the UniGene database maintained at the National Centre for Biotechnology Information (NCBI, Bethesda, MD, U.S.A.). We confirmed this localization by performing fluorescence in situ hybridization on BM88-positive cosmid clones isolated from a human genomic library. These results suggest that BM88 may be a candidate gene for genetic disorders associated with alterations at 11p15.5.

Also flagged:Igfibronectintransmembranetutltransmembrane proteinsKIAA1355
Journal Article 2001-05-01 No Snippets Bodily KD, Morrison CM, Renden RB, Broadie K.
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We describe here the cloning and functional characterization of a neural-specific novel member of the Ig superfamily, turtle (tutl), with a structure of five Ig C2-type domains, two fibronectin type III domains, and one transmembrane region. Alternative splicing of the tutl gene produces at least four Tutl isoforms, including two transmembrane proteins and two secreted proteins, with primary structures closely related to a human brain protein (KIAA1355), the Deleted in Colorectal Cancer/Neogenin/Frazzled receptor family, and the Roundabout/Dutt1 receptor family. An allelic series of tutl gene mutations resulted in recessive lethality to semilethality, indicating that the gene is essential. In contrast to other family members, tutl does not play a detectable role in axon pathfinding or nervous system morphogenesis. Likewise, basal synaptic transmission and locomotory movement are unaffected. However, tutl mutations cause striking movement defects exhibited in specific types of highly coordinated behavior. Specifically, tutl mutants display an abnormal response to tactile stimulation, the inability to regain an upright position from an inverted position (hence, "turtle"), and the inability to fly in adulthood. These phenotypes demonstrate that tutl plays an essential role in establishing a nervous system capable of executing coordinated motor output in complex behaviors.

Also flagged:transferrin receptor 2hemochromatosis type 3Hereditary hemochromatosischromosomeTFR2Methionine
Journal Article 2001-05-01 ✓ 5 Snippets Roetto A, Totaro A, Piperno A, Piga A, Longo F, Garozzo G, Calì A, De Gobbi M, Gasparini P, Camaschella C.
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The identification of new mutations of TFR2 confirms that this gene is associated with iron overload and offers a tool for molecular diagnosis in patients without HFE mutations.

…homozygosity in theHFEgene on chromosome…

…new type ofhemochromatosis(HFE3) has been…

…patient with nonfamilialhemochromatosis, a T-->A transversion…

…in patients withoutHFEmutations.…

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Hereditary hemochromatosis usually results from C282Y homozygosity in the HFE gene on chromosome 6p. Recently, a new type of hemochromatosis (HFE3) has been characterized in 2 unrelated Italian families with a disorder linked to 7q. Patients with HFE3 have transferrin receptor 2 (TFR2) inactivated by a homozygous nonsense mutation (Y250X). Here the identification of 2 new TFR2 mutations is reported. In a large inbred family from Campania, a frameshift mutation (84-88 insC) in exon 2 that causes a premature stop codon (E60X) is identified. In a single patient with nonfamilial hemochromatosis, a T-->A transversion (T515A), which causes a Methionine-->Lysine substitution at position 172 of the protein (M172K), has been characterized. TFR2 gene gives origin to 2 alternatively spliced transcripts-the alpha-transcript, which may encode a transmembrane protein, and the beta-transcript, a shorter, possibly intracellular variant. Based on their positions, the effects of the identified mutations on the 2 TFR2 forms are expected to differ. Y250X inactivates both transcripts, whereas E60X inactivates only the alpha-form. M172K has a complex effect: it causes a missense in the alpha-form, but it may also prevent the beta-form production because it affects its putative initiation codon. Analysis of the clinical phenotype of 13 HFE3 homozygotes characterized at the molecular level has shown a variable severity, from nonexpressing patients to severe clinical complications. The identification of new mutations of TFR2 confirms that this gene is associated with iron overload and offers a tool for molecular diagnosis in patients without HFE mutations.

Also flagged:Ironcell surfaceTransferrin receptorTfRTfcell-surface
Journal Article 2001-05-01 ✓ 5 Snippets Chitambar CR, Wereley JP.
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The impact of HFE on iron transport was examined in B-lymphoid cell lines developed from a patient with hemochromatosis with the HFE C282Y mutation (C282Y cells) and an individual with the wild-type HFE gene (WT cells).

The role of HFE in iron uptake by B cells may extend beyond its known interaction with the TfR.

…line with thehemochromatosisC282Y mutation.…

…The gene forhemochromatosis(HFE) is expressed…

…gene for hemochromatosis (HFE) is expressed in…

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The gene for hemochromatosis (HFE) is expressed in a variety of cells, including those not thought to be affected by this disease. The impact of HFE on iron transport was examined in B-lymphoid cell lines developed from a patient with hemochromatosis with the HFE C282Y mutation (C282Y cells) and an individual with the wild-type HFE gene (WT cells). Whereas both cell lines expressed HFE protein, C282Y cells displayed less HFE protein at the cell surface. Transferrin receptor (TfR) number was 2- to 3-fold greater in WT cells than in C282Y cells, while TfR affinity for transferrin (Tf) was slightly lower in C282Y cells. TfR distribution between intracellular and cell-surface compartments was similar in both cell lines. Iron uptake per cell was greater in WT cells but was not increased proportional to TfR number. When considered relative to cell-surface TfR number, however, iron uptake and Tf internalization were actually greater in C282Y cells. Surprisingly, Tf-independent iron uptake was also significantly greater in C282Y cells than in WT cells. The ferritin content of C282Y cells was approximately 40% that of WT cells. Exposure of cells to pro-oxidant conditions in culture led to a greater inhibition of proliferation in C282Y cells than in WT cells. Our results indicate that in this B-lymphoid cell line, the HFE C282Y mutation affects both Tf-dependent and -independent iron uptake and enhances cell sensitivity to oxidative stress. The role of HFE in iron uptake by B cells may extend beyond its known interaction with the TfR.

Also flagged:transferrin receptoranemiaTfRironmetabolismiron deficiency anemia
Journal Article 2001-05-01 ✓ 5 Snippets Barisani D, Parafioriti A, Armiraglio E, Meneveri R, Conte D.
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Twelve controls, 8 patients with iron deficiency anemia, 7 with HFE-related hemochromatosis, and 6 with non-HFE-related iron overload were studied.

Increased expression of both proteins is present only in HFE-related hemochromatotics suggesting that other factors may be involved in determining non-HFE-related iron overload phenotype.

…and 6 with non-HFE-related iron overload were studied. Immunohistochemistry…

…degree , in HFE-related hemochromatotics , whereas it…

…in patients with non-HFE-related iron overload. TfR expression showed a crypt-to-tip…

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<h4>Background & aims</h4>Stimulator of Fe Transport (SFT) and transferrin receptor (TfR) are proteins involved in iron transport. This study evaluated iron metabolism protein expression in duodenal biopsy specimens from controls and patients with abnormal iron metabolism.<h4>Methods</h4>Twelve controls, 8 patients with iron deficiency anemia, 7 with HFE-related hemochromatosis, and 6 with non-HFE-related iron overload were studied. Immunohistochemistry was performed on duodenal biopsy specimens with anti-TfR and anti-SFT antibodies which recognize a putative stimulator of Fe transport of ~80 kilodaltons.<h4>Results</h4>In controls, the putative stimulator of Fe transport was expressed in the middle and distal part of the villi in the subapical cytoplasmatic region. Its expression increased in anemics and, to a lesser degree, in HFE-related hemochromatotics, whereas it was reduced in patients with non-HFE-related iron overload. TfR expression showed a crypt-to-tip gradient in controls, but not in anemics, in whom it was uniformly overexpressed. TfR expression was intermediate in HFE-related hemochromatotics and similar to controls in non-HFE-related iron overload.<h4>Conclusions</h4>Expression of the putative stimulator of Fe transport and TfR increases in iron deficiency. Increased expression of both proteins is present only in HFE-related hemochromatotics suggesting that other factors may be involved in determining non-HFE-related iron overload phenotype.

Also flagged:irontransportersdivalent-metal transporter 1ferroportin 1iron deficiencyDMT1
Journal Article 2001-05-01 ✓ 5 Snippets Zoller H, Koch RO, Theurl I, Obrist P, Pietrangelo A, Montosi G, Haile DJ, Vogel W, Weiss G.
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Moreover, DMT1 and FP1 mRNA levels were significantly increased in patients with iron deficiency, HFE and non-HFE hemochromatosis, whereas they were unchanged in patients with secondary iron overload.

To gain insight into the regulatory properties of these transporters in the duodenum, we studied their expression in patients with hereditary hemochromatosis (HFE-associated and non-HFE-associated), secondary iron overload, and iron deficiency.

DMT1 and FP1 mRNA levels were significantly increased in patients with iron deficiency, HFE and non-HFE hemochromatosis

…h hereditary hemochromatosis (HFE-associated and non-HFE-associ…

…tosis (HFE-associated and non-HFE-associated), secondary iron o…

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<h4>Background & aims</h4>Imbalances of iron homeostasis are accompanied by alterations of intestinal iron absorption. The identification of divalent-metal transporter 1 (DMT1) and ferroportin 1 (FP1) has improved our understanding of transmembrane iron trafficking. To gain insight into the regulatory properties of these transporters in the duodenum, we studied their expression in patients with hereditary hemochromatosis (HFE-associated and non-HFE-associated), secondary iron overload, and iron deficiency.<h4>Methods</h4>DMT1, FP1 messenger RNA (mRNA), and protein expression were analyzed in duodenal biopsy specimens from patients by means of TaqMan real-time polymerase chain reaction, Western blotting technique, and immunohistochemistry.<h4>Results</h4>DMT1 and FP1 mRNA levels are positively correlated with each other in all patient groups (P < 0.001). Moreover, DMT1 and FP1 mRNA levels were significantly increased in patients with iron deficiency, HFE and non-HFE hemochromatosis, whereas they were unchanged in patients with secondary iron overload. Alterations in DMT1 and FP1 mRNA levels were paralleled by comparable changes in the duodenal expression of these proteins. In patients with normal iron status or iron deficiency, significant negative correlations between DMT1, FP1 mRNA, and serum iron parameters were found, which were absent in subjects with primary hemochromatosis.<h4>Conclusions</h4>DMT1 and FP1 are centrally involved in iron uptake/transfer in the duodenum and in the adaptive changes of iron homeostasis to iron deficiency and overload.

Also flagged:irondivalent metal transporterDMT1Fe2+Fe3+ferrireductases
Journal Article 2001-05-01 ✓ 5 Snippets Griffiths WJ, Sly WS, Cox TM.
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HFE-deficient mice with hemochromatosis

hemochromatosis and HFE

…is enhanced inHFE-deficient mice with hemochrom…

…HFE-deficient mice withhemochromatosis.…

…RNA occurs inhemochromatosisand HFE-knockout mice,…

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<h4>Background & aims</h4>Overexpression of duodenal divalent metal transporter (DMT1) messenger RNA occurs in hemochromatosis and HFE-knockout mice, suggesting that DMT1 mediates enhanced absorption of iron; however, increased expression of functional DMT1 protein has yet to be substantiated. We examined the role of DMT1 and the mucosal iron uptake defect in HFE-knockout mice.<h4>Methods</h4>Unidirectional iron uptake of 59Fe by small intestinal mucosa in vitro was compared between matched pairs of HFE-knockout and wild-type mice. DMT1-specific antibodies were used to block iron transport and to quantify duodenal protein expression.<h4>Results</h4>Ferrous iron uptake at 3.5-450 micromol/L was greatly enhanced in HFE-knockouts compared with wild-type, the apparent V(max) for Fe2+ transport being doubled (P < 0.01). Supplied as Fe3+, uptake was only enhanced in HFE-knockouts at < or =18 micromol/L, when the iron was almost completely converted to Fe2+ by mucosal ferrireductases. DMT1 antibody reduced the apparent Vmax for mucosal Fe2+ transport in HFE-knockouts to below wild-type control values (P < 0.02); immunoreactive mucosal DMT1 protein was increased nearly 2-fold in HFE-knockouts (P < 0.01).<h4>Conclusions</h4>Disruption of the HFE gene up-regulates functional DMT1 transporters and enhances uptake of ferrous iron by this mechanism; DMT1 also mediates increased uptake after reduction of ferric iron presented at physiological concentrations.

Also flagged:cell migrationcell surfacesemaphorin 3Adeathneuropilin-1binding
Journal Article 2001-05-01 ✓ 1 Snippet Bagnard D, Vaillant C, Khuth ST, Dufay N, Lohrum M, Puschel AW, Belin MF, Bolz J, Thomasset N.
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DCC

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The dynamic and coordinated interaction between cells and their microenvironment controls cell migration, proliferation, and apoptosis, mediated by different cell surface molecules. We have studied the response of a neuroectodermal progenitor cell line, Dev, to a guidance molecule, semaphorin 3A (Sema3A), described previously as a repellent-collapsing signal for axons, and we have shown that Sema3A acts as a repellent guidance cue for migrating progenitor cells and, on prolonged application, induces apoptosis. Both repulsion and induction of cell death are mediated by neuropilin-1, the ligand-binding component of the Sema3A receptor. The vascular endothelial growth factor, VEGF165, antagonizes Sema3A-induced apoptosis and promotes cell survival, migration, and proliferation. Surprisingly, repulsion by Sema3A also depends on expression of VEGFR1, a VEGF165 receptor, expressed in Dev cells. Moreover, we found that these repulsive effects of Sema3A require tyrosine kinase activity, which can be attributed to VEGFR1. These results indicate that the balance between guidance molecules and angiogenic factors can modulate the migration, apoptosis (or survival), and proliferation of neural progenitor cells through shared receptors.

Also flagged:polyglutaminecaspasemitochondrialcytochrome cautosomal dominant neurodegenerative diseasesHuntington's disease
Journal Article 2001-05-01 ✓ 1 Snippet Jana NR, Zemskov EA, Wang Gh, Nukina N.
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A hallmark of HD is the proteolytic production of N-terminal fragments of huntingtin containing polyglutamine repeats that form ubiquitinated aggregates in the nucleus and cytoplasm of the affected neurons.

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Expansion of CAG repeats within the coding region of target genes is the cause of several autosomal dominant neurodegenerative diseases including Huntington's disease (HD). A hallmark of HD is the proteolytic production of N-terminal fragments of huntingtin containing polyglutamine repeats that form ubiquitinated aggregates in the nucleus and cytoplasm of the affected neurons. In this study, we used an ecdysone-inducible stable mouse neuro2a cell line that expresses truncated N-terminal huntingtin (tNhtt) with different polyglutamine length, along with mice transgenic for HD exon 1, to demonstrate that the ubiquitin-proteasome pathway is involved in the pathogenesis of HD. Proteasomal 20S core catalytic component was redistributed to the polyglutamine aggregates in both the cellular and transgenic mouse models. Proteasome inhibitor dramatically increased the rate of aggregate formation caused by tNhtt protein with 60 glutamine (60Q) repeats, but had very little influence on aggregate formation by tNhtt protein with 150Q repeats. Both normal and polyglutamine-expanded tNhtt proteins were degraded by proteasome, but the rate of degradation was inversely proportional to the repeat length. The shift of the proteasomal components from the total cellular environment to the aggregates, as well as the comparatively slower degradation of tNhtt with longer polyglutamine, decreased the proteasome's availability for degrading other key target proteins, such as p53. This altered proteasomal function was associated with disrupted mitochondrial membrane potential, released cytochrome c from mitochondria into the cytosol and activated caspase-9- and caspase-3-like proteases. These results suggest that the impaired proteasomal function plays an important role in polyglutamine protein-induced cell death.

Also flagged:cell developmenttouch receptormec-2mig-21vab-15migrations
Journal Article 2001-05-01 No Snippets Du H, Chalfie M.
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To identify genes regulating the development of the six touch receptor neurons, we screened the F(2) progeny of mutated animals expressing an integrated mec-2::gfp transgene that is expressed mainly in these touch cells. From 2638 mutated haploid genomes, we obtained 11 mutations representing 11 genes that affected the production, migration, or outgrowth of the touch cells. Eight of these mutations were in known genes, and 2 defined new genes (mig-21 and vab-15). The mig-21 mutation is the first known to affect the asymmetry of the migrations of Q neuroblasts, the cells that give rise to two of the six touch cells. vab-15 is a msh-like homeobox gene that appears to be needed for the proper production of touch cell precursors, since vab-15 animals lacked the four more posterior touch cells. The remaining touch cells (the ALM cells) were present but mispositioned. A similar touch cell phenotype is produced by mutations in lin-32. A more severe phenotype; i.e., animals often lacked ALM cells, was seen in lin-32 vab-15 double mutants, suggesting that these genes acted redundantly in ALM differentiation. In addition to the touch cell abnormalities, vab-15 animals variably exhibit embryonic or larval lethality, cell degenerations, malformation of the posterior body, uncoordinated movement, and defective egg laying.

Also flagged:ferrocenenucleotidesbindingelectron transferferroceneshereditary hemochromatosis
Journal Article 2001-05-01 ✓ 1 Snippet Umek RM, Lin SW, Vielmetter J, Terbrueggen RH, Irvine B, Yu CJ, Kayyem JF, Yowanto H, Blackburn GF, Farkas DH, Chen YP.
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Hfe

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A novel platform for the electronic detection of nucleic acids on microarrays is introduced and shown to perform well as a selective detection system for applications in molecular diagnostics. A gold electrode in a printed circuit board is coated with a self-assembled monolayer (SAM) containing DNA capture probes. Unlabeled nucleic acid targets are immobilized on the surface of the SAM through sequence-specific hybridization with the DNA capture probe. A separate signaling probe, containing ferrocene-modified nucleotides and complementary to the target in the region adjoining the capture probe binding site, is held in close proximity to the SAM in a sandwich complex. The SAM allows electron transfer between the immobilized ferrocenes and the gold, while insulating the electrode from soluble redox species, including unbound signaling probes. Here, we demonstrate sequence-specific detection of amplicons after simple dilution of the reaction product into hybridization buffer. In addition, single nucleotide polymorphism discrimination is shown. A genotyping chip for the C282Y single nucleotide polymorphism associated with hereditary hemochromatosis is used to confirm the genotype of six patients' DNA. In addition, a gene expression-monitoring chip is described that surveys five genes that are differentially regulated in the cellular apoptosis response. Finally, custom modification of individual electrodes through sequence-specific hybridization demonstrates the potential of this system for infectious disease diagnostics. The versatility of the electronic detection platform makes it suitable for multiple applications in diagnostics and pharmacogenetics.

Also flagged:-cell receptorhereditary hemochromatosisCD8HHcell receptorCD4
Journal Article 2001-05-01 ✓ 4 Snippets Cardoso C, Porto G, Lacerda R, Resende D, Rodrigues P, Bravo F, Oliveira JC, Justiça B, de Sousa M.
In-Text Gene Mentions

These findings suggest that Hfe has an effect in the shaping of T-cell populations either directly, as indicated by the lymphopenia seen in the two chains in C282Y heterozygous without iron overload, or indirectly by contributing to iron overload pathology.

…study of 32hemochromatosispatients and 274…

…genotyped for theHfemutations, C282Y and…

…findings suggest thatHfehas an effect…

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Low CD8(+) T lymphocyte numbers have contributed to deciphering the genotype/phenotype discrepancies found in hereditary hemochromatosis (HH) patients genotyped for the Hfe mutations, C282Y and H63D. In this study, we extend the analysis of T lymphocytes in HH to the T cell receptor (TcR) repertoire. Thirty-two HH patients (C282Y homozygous) and 274 Hfe genotyped healthy subjects were studied. The following TcR chains were analyzed: Valpha2.3, Vbeta5.1, Vbeta5.2, Vbeta5.3, Vbeta6.7, Vbeta8, and Vbeta12 among the CD4(+) and CD8(+) populations. Lymphopenias and absence of expansions of the Vbeta5.2 and Vbeta12 chains in the CD8(+) pool were seen in controls heterozygous for the C282Y mutation. Expansions in the control group were seen within the CD8(+) pool and were rare/absent within the CD4(+) pool. TcR expansions were found more frequent in patients with iron overload related pathology than in patients without pathology. 9/16 of the patients with pathology have at least one expansion among the CD8(+) pool a number significantly higher compared with patients without pathology (1/16). These findings suggest that Hfe has an effect in the shaping of T-cell populations either directly, as indicated by the lymphopenia seen in the two chains in C282Y heterozygous without iron overload, or indirectly by contributing to iron overload pathology.

Also flagged:protein Cprotein Santithrombin IIIfactor XIIIPCPS
Journal Article 2001-05-01 ✓ 3 Snippets Ogasawara MS, Aoki K, Katano K, Ozaki Y, Suzumori K.
In-Text Gene Mentions

…(PS), antithrombin III (ATIII), factor XII (FXII),…

…of PC, PS,ATIII, and FXIII.…

…in PC, PS,ATIII, or FXIII) predicts…

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<h4>Objective</h4>To investigate whether a decrease in the values of protein C (PC), protein S (PS), antithrombin III (ATIII), factor XII (FXII), or factor XIII (FXIII) has predictive value for subsequent miscarriages.<h4>Design</h4>Prospective study.<h4>Setting</h4>Nagoya City University Medical School.<h4>Patient(s)</h4>A total of 536 patients with a history of two or more first-trimester miscarriages.<h4>Intervention(s)</h4>One hundred and twelve patients treated with low-dose aspirin were excluded from the analysis.<h4>Main outcome measure(s)</h4>The subsequent pregnancy outcome of 424 patients was compared for abnormal and normal levels of each parameter.<h4>Result(s)</h4>There were no differences in the subsequent miscarriage rates between abnormal and normal values of PC, PS, ATIII, and FXIII. However, the rate with abnormal FXII is significantly higher than that with normal FXII.<h4>Conclusion(s)</h4>A decrease in FXII (but not in PC, PS, ATIII, or FXIII) predicts subsequent miscarriage in patients with a history of first-trimester recurrent miscarriages.

Also flagged:prostatic steroid binding proteinPSBPIL-2lymphocyte proliferationOVA
Journal Article 2001-05-01 No Snippets Maccioni M, Riera CM, Rivero VE.
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Prostatic steroid binding protein (PSBP) is the major protein produced ( approximately 20% of the total cytosolic protein) and secreted into the seminal fluid by the rat ventral prostate but its physiological function has not been elucidated yet. Since PSBP is secreted into the seminal fluid (which is itself a potent immunosuppressor) and has strong homology with uteroglobin (which possess an important anti-inflammatory function) our aim was to determine what effect, if any, PSBP would have on the immune system. With that purpose in mind we performed mononuclear cell cultures in the presence or absence of purified PSBP and analysed the effect of this protein on different functional parameters. PSBP inhibits the mitogen-induced proliferation of normal rat spleen mononuclear cells (MNC) specifically and in a dose-dependent manner. It reduces the production of IL-2 and the expression of its receptor (analysed by flow cytometry) which are important events for lymphocyte proliferation. Also, PSBP was able to inhibit OVA-specific proliferation of lymph node cells from previously primed animals. The immunosuppressive effect of PSBP is not due to an inherent toxic effect to the cells, since the cell viability was kept intact at the different times of culture studied. We also analysed the effect of rat PSBP on mitogen-induced proliferation of mouse spleen and human blood MNC. The proliferation was strongly abolished in a dose-dependent and non-species specific fashion. Moreover, PSBP strongly inhibits the human mixed lymphocyte reaction. Taken together, the present data support evidence for a new type of function for PSBP. We report that PSBP is a potent immunosuppressor factor and we describe its effect on the immune function in vitro. Here, we discuss the possible implications of these findings in the protection of sperm from immunologic damage in the feminine reproductive tract.

Also flagged:Localizationnetrin guidance receptornetrin-1axonaxonal
Journal Article 2001-05-01 ✓ 5 Snippets Seaman C, Anderson R, Emery B, Cooper HM.
In-Text Gene Mentions

DCC, in the developing peripheral and enteric nervous

DCC, have been shown to be an essential guidance system driving axon pathfinding within the developing vertebrate central nervous

DCC guidance receptor in the development of the mammalian peripheral and enteric nervous

DCC guidance receptor in the development of the mammalian peripheral and enteric nervous systems (PNS

DCC receptor is present in the developing mouse PNS

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Over recent years the secreted guidance cue, netrin-1, and its receptor, DCC, have been shown to be an essential guidance system driving axon pathfinding within the developing vertebrate central nervous system (CNS). Mice lacking DCC exhibit severe defects in commissural axon extension towards the floor plate demonstrating that the DCC-netrin guidance system is largely responsible for directing axonal projections toward the ventral midline in the developing spinal cord (Fazeli et al., Nature 386 (1997) 796). In addition, these mutants lack several major commissures within the forebrain, including the corpus callosum and the hippocampal commissure. In contrast to the CNS, the role of the DCC guidance receptor in the development of the mammalian peripheral and enteric nervous systems (PNS and ENS) has not been investigated. Here we demonstrate using immunohistochemical analysis that the DCC receptor is present in the developing mouse PNS where it is found on spinal, segmental, and sciatic nerves, and in developing sensory ganglia and their associated axonal projections. In addition, DCC is present in the ENS throughout the early developmental phase.

Also flagged:IFS
Journal Article 2001-05-01 ✓ 2 Snippets Wang D, Imajo T, Tanaka K, Tanaka T, Bürger H.
In-Text Gene Mentions

…For the DCC(35)Cl isotopomer, the nu(1) as …

…n contrast, for the DCC(37)Cl isotopomer, t…

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High-resolution infrared spectra of the nu(1) and nu(2) bands of DCCCl were observed using Bruker IFS 120HR Fourier transform spectrometers at resolutions of 0.0044 and 0.0035 cm(-1), respectively. For the DCC(35)Cl isotopomer, the nu(1) as well as the nu(2) band was found to be heavily perturbed. Detailed analyses revealed that the nu(1) state is in resonance with the l=0 substate of the nu(3)+4nu(4) state and that the nu(2) state is in resonance with the l=0 substate of the nu(3)+4nu(5) state. The rotational constants played a key role in identifying the perturbing states. In contrast, for the DCC(37)Cl isotopomer, the rotational structures of the nu(1) and nu(2) states are almost regular but slightly perturbed by interactions with the nu(3)+4nu(4) and nu(3)+4nu(5) states, respectively. The constants of resonances as well as the molecular constants for the nu(1), nu(2), nu(3)+4nu(4) and nu(3)+4nu(5) states were determined. Copyright 2001 Academic Press.

Also flagged:oligonucleotidepolymerasecanceroncogenesbreast cancerBreast Cancers
Journal Article 2001-05-01 ✓ 1 Snippet Daigo Y, Chin SF, Gorringe KL, Bobrow LG, Ponder BA, Pharoah PD, Caldas C.
In-Text Gene Mentions

CSE1L

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We have developed a protocol for degenerate oligonucleotide-primed-polymerase chain reaction-based array comparative genomic hybridization (array CGH) that, when combined with a laser microdissection technique, allows the analysis of cancer cell populations isolated from routine, formalin-fixed, paraffin-embedded tissue samples. Comparison of copy number changes detected by degenerate oligonucleotide-primed-polymerase chain reaction-based array CGH to those detected by conventional array CGH or fluorescence in situ hybridization, demonstrated that amplifications can be reliably detected. Using a genomic microarray containing 57 oncogenes, we screened a total of 28 breast cancer samples and obtained a detailed amplicon profile that is the most comprehensive to date in human breast cancer. The array CGH method described here will allow the genetic analysis of paraffin-embedded human cancer materials for example in the context of clinical trials.

Also flagged:Carcinoid tumorsneuroendocrine tumorscarcinoidsmidgut carcinoidstumorstumor
Journal Article 2001-05-01 ✓ 1 Snippet Kytölä S, Höög A, Nord B, Cedermark B, Frisk T, Larsson C, Kjellman M.
In-Text Gene Mentions

DCC

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Carcinoid tumors are rare neuroendocrine tumors occurring in the lung or in the digestive tract where they are further subclassified as foregut, midgut, or hindgut carcinoids. To gain a better understanding of the genetic basis of the different types of carcinoid tumors, we have characterized numerical imbalances in a series of midgut carcinoids, and compared the results to previous findings in carcinoids from the lung. Numerical imbalances were revealed in 16 of the 18 tumors, and the most commonly detected aberrations were losses of 18q22-qter (67%), 11q22-q23 (33%), and 16q21-qter (22%), and gain of 4p14-qter (22%). The total number of alterations found in the metastases was significantly higher than in the primary tumors, indicating the accumulation of acquired genetic changes in the tumor progression. Losses of 18q and 11q were present both in primary tumors and metastases, whereas loss of 16q and gain of 4 were only detected in metastases. Furthermore, the pattern of comparative genomic hybridization alterations varied depending on the total number of detected alterations. Taken together, the findings would suggest a progression of numerical imbalances, in which loss of 18q and 11q represent early events, and loss of 16q and gain of 4p are late events in the tumor progression of midgut carcinoids. When compared to previously published comparative genomic hybridization abnormalities in lung carcinoids, loss of 11q was found to occur in both tumor types, whereas loss of 18q and 16q and gain of 4 were not revealed in lung carcinoids. The results indicate that inactivation of a putative tumor suppressor gene in 18q22-qter represents a frequent and early event that is specific for the development of midgut carcinoids.

Also flagged:hereditary hemochromatosisHHironSFT
Journal Article 2001-05-01 ✓ 5 Snippets Knutson MD, Levy JE, Andrews NC, Wessling-Resnick M.
In-Text Gene Mentions

Hfe(-/-) mice and HH patients include not only differences in the relative rate and magnitude of iron loading but also the lack of fibrosis

Hfe knockout (-/-) mice recapitulate many of the biochemical abnormalities of hereditary hemochromatosis

…not enhanced inHfeknockout mice.…

Hfeknockout (-/-) mice…

…mRNA expression inHfe(-/-) mice.…

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Hfe knockout (-/-) mice recapitulate many of the biochemical abnormalities of hereditary hemochromatosis (HH), but the molecular mechanisms involved in the etiology of iron overload in HH remain poorly understood. It was found previously that livers of patients with HH contained 5-fold higher SFT (stimulator of Fe transport) mRNA levels relative to subjects without HH. Because this observation suggests a possible role for SFT in HH, we investigated SFT mRNA expression in Hfe(-/-) mice. The 4- and 10-wk-old Hfe(-/-) mice do not have elevated levels of hepatic SFT transcripts relative to age-matched Hfe(+/+) mice, despite having 2.2- and 3.3-fold greater hepatic nonheme iron concentrations, respectively. Northern blot analyses of various mouse tissues revealed that SFT is widely expressed. The novel observation that SFT transcripts are abundant in brain prompted a comparison of SFT transcript levels and nonheme iron levels in the brains of Hfe(+/+) and Hfe(-/-) mice. Neither SFT mRNA levels nor nonheme iron levels differed between groups. Further comparisons of Hfe(-/-) and Hfe(+/+) mouse tissues revealed no significant differences in SFT mRNA levels in duodenum, the site of increased iron absorption in HH. Important distinctions between Hfe(-/-) mice and HH patients include not only differences in the relative rate and magnitude of iron loading but also the lack of fibrosis and phlebotomy treatment in the knockout animals.

Also flagged:cholesterolphospholipidbile acidmetabolismchronic proliferative cholangitispathogenesis
Journal Article 2001-05-01 No Snippets Shoda J, Oda K, Suzuki H, Sugiyama Y, Ito K, Cohen DE, Feng L, Kamiya J, Nimura Y, Miyazaki H, Kano M, Matsuzaki Y, Tanaka N.
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Intrahepatic calculi, highly prevalent in the Far East, including Japan, are characterized clinically by chronic proliferative cholangitis with frequent stone recurrences. Intrahepatic calculi consist of 2 groups, i.e., brown pigment stones, including a high cholesterol content, and cholesterol stones, with the former predominating. To gain insights into the pathogenesis of intrahepatic calculi, cholesterol and bile acid biosynthesis, as well as alterations in intracellular transport and/or canalicular secretion of phospholipid and bile acid were investigated in liver of patients with intrahepatic calculi. Enzyme activities of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase were increased (12.8 +/- 1.9 pmol/min/mg protein, mean +/- SEM vs. 5.5 +/- 0.4 in controls; P < .01) and cholesterol 7 alpha-hydroxylase activities were decreased (1.3 +/- 0.4 vs. 4.9 +/- 0.6; P < .01) in liver specimens of patients with brown pigment stones. In addition, messenger RNA (mRNA) levels of multidrug resistance P-glycoprotein 3 (MDR3 Pgp) and phosphatidylcholine transfer protein (PCTP) were markedly low in the liver specimens compared with the levels in specimens of control subjects, gallbladder stone patients, and patients with obstructive cholestasis. The protein levels and the immunohistochemical staining were decreased for MDR3 Pgp and PCTP in the liver. Consistently, the concentrations of phospholipid were markedly reduced in the hepatic bile from both affected and unaffected hepatic segments. In patients with intrahepatic calculi, biliary cholesterol supersaturation and the formation of cholesterol-rich brown pigment as well as cholesterol stones may be attributed to decreased hepatic transport and biliary secretion of phospholipids, in the setting of increased cholesterogenesis and decreased bile acid synthesis.

Also flagged:N-type VDCCN-type VDCCsnerve injuryN-type Ca 2+ channelvoltage-dependent Ca 2+ channelsvoltage-dependent Ca 2+ channel
Journal Article 2001-05-01 ✓ 1 Snippet Saegusa H, Kurihara T, Zong S, Kazuno A, Matsuda Y, Nonaka T, Han W, Toriyama H, Tanabe T.
In-Text Gene Mentions

Cacna1e

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The importance of voltage-dependent Ca2+ channels (VDCCs) in pain transmission has been noticed gradually, as several VDCC blockers have been shown to be effective in inhibiting this process. In particular, the N-type VDCC has attracted attention, because inhibitors of this channel are effective in various aspects of pain-related phenomena. To understand the genuine contribution of the N-type VDCC to the pain transmission system, we generated mice deficient in this channel by gene targeting. We report here that mice lacking N-type VDCCs show suppressed responses to a painful stimulus that induces inflammation and show markedly reduced symptoms of neuropathic pain, which is caused by nerve injury and is known to be difficult to treat by currently available therapeutic methods. This finding clearly demonstrates that the N-type VDCC is essential for development of neuropathic pain and, therefore, controlling the activity of this channel can be of great importance for the management of neuropathic pain.

Also flagged:glioblastoma multiformeoncogenesGBMcancersTumornucleotides
Journal Article 2001-05-01 ✓ 1 Snippet Hui AB, Lo KW, Yin XL, Poon WS, Ng HK.
In-Text Gene Mentions

…(64.3%), EGFR (57.1%),CSE1L(57.1%), NRAS (50%),…

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We have used a new method of genomic microarray to investigate amplification of oncogenes throughout the genome of glioblastoma multiforme (GBM). Array-based comparative genomic hybridization (array CGH) allows for simultaneous examination of 58 oncogenes/amplicons that are commonly amplified in various human cancers. Amplification of multiple oncogenes in human cancers can be rapidly determined in a single experiment. Tumor DNA and normal control DNA were labeled by nick translation with green- and red-tagged nucleotides, respectively. Instead of hybridizing to normal metaphase chromosomes in conventional comparative genomic hybridization (CGH), the probes of the mixed fluorescent labeled DNA were applied to genomic array templates comprised of P1, PAC, and BAC clones of 58 target oncogenes. The baseline for measuring deviations was established by performing a series of independent array CGH using test and reference DNA made from normal individuals. In the present study, we examined fourteen GBMs (seven cell lines and seven tumours) with CGH and array CGH to reveal the particular oncogenes associated with this cancer. High-level amplifications were identified on the oncogenes/amplicons CDK4, GLI, MYCN, MYC, MDM2, and PDGFRA. The highest frequencies of gains were detected on PIK3CA (64.3%), EGFR (57.1%), CSE1L (57.1%), NRAS (50%), MYCN (42.9%), FGR (35.7%), ESR (35.7%), PGY1 (35.7%), and D17S167 (35.7%). These genes are suggested to be involved in the GBM tumorigenesis.

Also flagged:epimorphinlumentranscription factorLIPLAPMorphogenesis
Journal Article 2001-05-01 No Snippets Hirai Y, Radisky D, Boudreau R, Simian M, Stevens ME, Oka Y, Takebe K, Niwa S, Bissell MJ.
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We have shown previously that epimorphin (EPM), a protein expressed on the surface of myoepithelial and fibroblast cells of the mammary gland, acts as a multifunctional morphogen of mammary epithelial cells. Here, we present the molecular mechanism by which EPM mediates luminal morphogenesis. Treatment of cells with EPM to induce lumen formation greatly increases the overall expression of transcription factor CCAAT/enhancer binding protein (C/EBP)beta and alters the relative expression of its two principal isoforms, LIP and LAP. These alterations were shown to be essential for the morphogenetic activities, since constitutive expression of LIP was sufficient to produce lumen formation, whereas constitutive expression of LAP blocked EPM-mediated luminal morphogenesis. Furthermore, in a transgenic mouse model in which EPM expression was expressed in an apolar fashion on the surface of mammary epithelial cells, we found increased expression of C/EBPbeta, increased relative expression of LIP to LAP, and enlarged ductal lumina. Together, our studies demonstrate a role for EPM in luminal morphogenesis through control of C/EBPbeta expression.

Also flagged:polypeptideschaperoneproteasomedegradationinclusion bodiesneurodegenerative diseases
Journal Article 2001-05-01 No Snippets Meriin AB, Mabuchi K, Gabai VL, Yaglom JA, Kazantsev A, Sherman MY.
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Abnormal proteins, which escape chaperone-mediated refolding or proteasome-dependent degradation, aggregate and form inclusion bodies (IBs). In several neurodegenerative diseases, such IBs can be formed by proteins with expanded polyglutamine (polyQ) domains (e.g., huntingtin). This work studies the regulation of intracellular IB formation using an NH(2)-terminal fragment of huntingtin with expanded polyQ domain. We demonstrate that the active form of MEKK1, a protein kinase that regulates several stress-activated signaling cascades, stimulates formation of the IBs. This function of MEKK1 requires kinase activity, as the kinase-dead mutant of MEKK1 cannot stimulate this process. Exposure of cells to UV irradiation or cisplatin, both of which activate MEKK1, also augmented the formation of IBs. The polyQ-containing huntingtin fragment exists in cells in two distinct forms: (a) in a discrete soluble complex, and (b) in association with insoluble fraction. MEKK1 strongly stimulated recruitment of polyQ polypeptides into the particulate fraction. Notably, a large portion of the active form of MEKK1 was associated with the insoluble fraction, concentrating in discrete sites, and polyQ-containing IBs always colocalized with them. We suggest that MEKK1 is involved in a process of IB nucleation. MEKK1 also stimulated formation of IBs with two abnormal polypeptides lacking the polyQ domain, indicating that this kinase has a general effect on protein aggregation.

Also flagged:netrin receptorin colon cancertransmembraneimmunoglobulinnetrin-1 receptorcell surface
Journal Article 2001-05-01 ✓ 5 Snippets Teyssier JR, Rousset F, Garcia E, Cornillet P, Laubriet A.
In-Text Gene Mentions

DCC (deleted in colon cancer

…the netrin receptor (DCC) gene during activation…

…TheDCC(deleted in colon…

…have assessed theDCCmRNA level in…

…Expression ofDCCwas also assessed…

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The DCC (deleted in colon cancer) gene has a brain restricted high expression pattern. It encodes a transmembrane protein of the immunoglobulin superfamily identified as the netrin-1 receptor. It might be a member of the so called "brain-lymphoid" molecules, which control key cell surface events. To test this hypothesis we have assessed the DCC mRNA level in human normal and malignant myeloid and lymphoid cells. A high mRNA content has been observed only in mature B cells at the secreting or presecreting stage. Expression of DCC was also assessed in the anti-CD40 model of immunopoiesis. Activation of purified tonsillar B cells by anti-CD 40 antibody strongly increased the DCC mRNA level and this effect was dramatically enhanced by the association of IL-2 + IL-10, which is a potent and selective in vitro inducer of the B cell memory phenotype. In contrast no effect has been detected after activation of T cells by anti-CD3. These data suggest that the DCC encoded netrin receptor is involved in B cell immunopoiesis.

Also flagged:polyglutamineglutaminescentrosomesvimentinproteasomeinclusion bodies
Journal Article 2001-05-01 No Snippets Waelter S, Boeddrich A, Lurz R, Scherzinger E, Lueder G, Lehrach H, Wanker EE.
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The huntingtin exon 1 proteins with a polyglutamine repeat in the pathological range (51 or 83 glutamines), but not with a polyglutamine tract in the normal range (20 glutamines), form aggresome-like perinuclear inclusions in human 293 Tet-Off cells. These structures contain aggregated, ubiquitinated huntingtin exon 1 protein with a characteristic fibrillar morphology. Inclusion bodies with truncated huntingtin protein are formed at centrosomes and are surrounded by vimentin filaments. Inhibition of proteasome activity resulted in a twofold increase in the amount of ubiquitinated, SDS-resistant aggregates, indicating that inclusion bodies accumulate when the capacity of the ubiquitin-proteasome system to degrade aggregation-prone huntingtin protein is exhausted. Immunofluorescence and electron microscopy with immunogold labeling revealed that the 20S, 19S, and 11S subunits of the 26S proteasome, the molecular chaperones BiP/GRP78, Hsp70, and Hsp40, as well as the RNA-binding protein TIA-1, the potential chaperone 14-3-3, and alpha-synuclein colocalize with the perinuclear inclusions. In 293 Tet-Off cells, inclusion body formation also resulted in cell toxicity and dramatic ultrastructural changes such as indentations and disruption of the nuclear envelope. Concentration of mitochondria around the inclusions and cytoplasmic vacuolation were also observed. Together these findings support the hypothesis that the ATP-dependent ubiquitin-proteasome system is a potential target for therapeutic interventions in glutamine repeat disorders.

Also flagged:ubiquitinproteasomeneurodegenerative disorderscystic fibrosis transmembrane conductance regulatorproteolysiscell division
Journal Article 2001-05-01 No Snippets Bence NF, Sampat RM, Kopito RR.
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Intracellular deposition of aggregated and ubiquitylated proteins is a prominent cytopathological feature of most neurodegenerative disorders. Whether protein aggregates themselves are pathogenic or are the consequence of an underlying molecular lesion is unclear. Here, we report that protein aggregation directly impaired the function of the ubiquitin-proteasome system. Transient expression of two unrelated aggregation-prone proteins, a huntingtin fragment containing a pathogenic polyglutamine repeat and a folding mutant of cystic fibrosis transmembrane conductance regulator, caused nearly complete inhibition of the ubiquitin-proteasome system. Because of the central role of ubiquitin-dependent proteolysis in regulating fundamental cellular events such as cell division and apoptosis, our data suggest a potential mechanism linking protein aggregation to cellular disregulation and cell death.

Also flagged:haemochromatosiscardiovascular diseasesgenetic disorderironbrain infarctionarteriosclerosis
Journal Article 2001-05-01 ✓ 5 Snippets Hetet G, Elbaz A, Gariepy J, Nicaud V, Arveiler D, Morrison C, Kee F, Evans A, Simon A, Amarenco P, Cambien F, Grandchamp B.
In-Text Gene Mentions

These three studies do not provide consistent evidence supporting the hypothesis that HFE mutations are associated with an increased risk of cardiovascular disease and with the development of arteriosclerosis.

In the present work, we have determined the HFE genotypes for C282Y and H63D in subjects from two case-control studies: the ECTIM and GENIC studies, designed to identify genetic variants associated with myocardial and brain infarction, respectively.

Positive association studies have been recently published between cardiovascular diseases and heterozygosity for the major mutation C282Y in the haemochromatosis gene HFE.<h4>Methods</h4>In the present work, we have determined the HFE genotypes for C282Y and H63D in subjects from two case-control studies: the ECTIM and GENIC studies, designed to identify genetic variants associated with myocardial and brain infarction, respectively.

In addition, we tested whether HFE mutations were associated with the degree of arteriosclerosis assessed non-invasively by Doppler ultrasonography on the carotid and femoral arteries, in a group of apparently healthy individuals (the AXA Study).<h4>Results</h4>The prevalence of 282Y, and 63D allele carriers, did not differ between cases and controls in the ECTIM and in the GENIC studies, while 63D but not 282Y carriers were more numerous among subjects with atherosclerotic plaques in the AXA Study.<h4>Conclusions</h4>These three studies do not provide consistent evidence supporting the hypothesis that HFE mutations are associated with an increased risk of cardiovascular disease and with the development of arteriosclerosis.

…the haemochromatosis geneHFE.<h4>Methods</h4>In the presen…

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<h4>Background</h4>Haemochromatosis is a common genetic disorder, inherited as an autosomal recessive trait that results in a progressive accumulation of iron in most tissues of the body. Positive association studies have been recently published between cardiovascular diseases and heterozygosity for the major mutation C282Y in the haemochromatosis gene HFE.<h4>Methods</h4>In the present work, we have determined the HFE genotypes for C282Y and H63D in subjects from two case-control studies: the ECTIM and GENIC studies, designed to identify genetic variants associated with myocardial and brain infarction, respectively. In addition, we tested whether HFE mutations were associated with the degree of arteriosclerosis assessed non-invasively by Doppler ultrasonography on the carotid and femoral arteries, in a group of apparently healthy individuals (the AXA Study).<h4>Results</h4>The prevalence of 282Y, and 63D allele carriers, did not differ between cases and controls in the ECTIM and in the GENIC studies, while 63D but not 282Y carriers were more numerous among subjects with atherosclerotic plaques in the AXA Study.<h4>Conclusions</h4>These three studies do not provide consistent evidence supporting the hypothesis that HFE mutations are associated with an increased risk of cardiovascular disease and with the development of arteriosclerosis.

Also flagged:growth conegrowth conescytoskeletonserotoninmyosin light chain kinasephorbol ester
Journal Article 2001-05-01 ✓ 1 Snippet Zhou FQ, Cohan CS.
In-Text Gene Mentions

…signals, such as Netrin/DCCand Slit/Robo, are…

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Repulsive guidance cues can either collapse the whole growth cone to arrest neurite outgrowth or cause asymmetric collapse leading to growth cone turning. How signals from repulsive cues are translated by growth cones into this morphological change through rearranging the cytoskeleton is unclear. We examined three factors that are able to induce the collapse of extending Helisoma growth cones in conditioned medium, including serotonin, myosin light chain kinase inhibitor, and phorbol ester. To study the cytoskeletal events contributing to collapse, we cultured Helisoma growth cones on polylysine in which lamellipodial collapse was prevented by substrate adhesion. We found that all three factors that induced collapse of extending growth cones also caused actin bundle loss in polylysine-attached growth cones without loss of actin meshwork. In addition, actin bundle loss correlated with specific filamentous actin redistribution away from the leading edge that is characteristic of repulsive factors. Finally, we provide direct evidence using time-lapse studies of extending growth cones that actin bundle loss paralleled collapse. Taken together, these results suggest that actin bundles could be a common cytoskeletal target of various collapsing factors, which may use different signaling pathways that converge to induce growth cone collapse.

Also flagged:Hereditary hemochromatosis
Journal Article 2001-05-01 ✓ 5 Snippets Moczulski DK, Grzeszczak W, Gawlik B.
In-Text Gene Mentions

The most frequent mutation causing hemochromatosis is C282Y in the HFE gene, the highest frequency of which has been observed in populations of Celtic origin.

…Frequency of thehemochromatosisC282Y and H63D…

…frequent mutation causinghemochromatosisis C282Y in…

…C282Y in theHFEgene, the highest…

…mutations in theHFEgene in populations…

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<h4>Background</h4>Hereditary hemochromatosis is one of the most common monogenic diseases among Caucasians. The most frequent mutation causing hemochromatosis is C282Y in the HFE gene, the highest frequency of which has been observed in populations of Celtic origin. There are no studies providing information about the frequency of the C282Y and H63D mutations in the HFE gene in populations of Slavic origin.<h4>Material and methods</h4>We collected 871 healthy unrelated subjects in Poland to assess the relevant frequencies. Each subject was genotyped for the C282Y and H63D mutations using a PCR-based protocol.<h4>Results</h4>Among the analysed subjects 6.0% were CY heterozygotes, and only one person was YY homozygote. The observed frequency of the 282Y allele was 3.1%. The frequency of the D allele of the H63D polymorphism was 16.2%. There were 13 (1.5%) compound heterozygotes for C282Y and H63D found in the analysed group.<h4>Conclusion</h4>The high frequency of the Y allele in this Polish population of non-Celtic origin may indicate an early introduction of this mutation through admixture with a strong positive selection.

Also flagged:colorectal cancerc-erbB2RhoDPC4Ecadherin
Journal Article 2001-05-01 ✓ 1 Snippet Yamaguchi A.
In-Text Gene Mentions

…such as nm23,DCC, and DPC4 may…

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It has been confirmed that several genes are involved in each step of liver metastasis of colorectal cancer. This article reviews recent highlights in this field. The expression of c-erbB2 or Rho protein in colorectal cancer tissues correlates closely with liver metastasis. Suppressor genes such as nm23, DCC, and DPC4 may play a role in the suppression of liver metastasis. On the other hand, the E-cadherin-catenin system, carbohydrate chains, selectin, and variant CD44 are known to play an important role in cells migration from the primary lesion, the adhesion of tumor cells to endothelial cells, and cell motility. These adhesion molecules may be a biological marker of liver metastasis. In addition, treatment targeting these genes will be a potent therapy for liver metastasis in the future.

Also flagged:colon cancerLiver metastasiscolorectal cancercytosine deaminasecytokinemajor histocompatibility complex class I
Journal Article 2001-05-01 ✓ 2 Snippets Yamamoto H, Sekimoto M, Monden M.
In-Text Gene Mentions

Basic research provided several candidates for the liver metastasis-associated genes, including MMP7, DCC, CDC25B, E-cadherin, CD44, vascular endothelial growth factor, etc. There is an alternative approach to liver metastasis, which attempts to introduce a specific gene such as cytosine deaminase and TIMP-2 into the hepatocytes but not into the tumor itself.

…genes, including MMP7,DCC, CDC25B, E-cadherin, CD44,…

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Liver metastasis is the most serious event for physicians and surgeons treating patients with colorectal cancer. Gene therapy is expected to become a novel strategy to prevent liver metastasis. Four types of clinical studies are currently underway: 1) suicide-gene therapy with the cytosine deaminase gene; 2) immune gene therapy with cytokine (inter leukin-2) or major histocompatibility complex class I gene HLA-B7; 3) tumor suppressor gene p53 therapy; and 4) lysis of p53 mutant cancer cells with E1B55k-deleted adenovirus (Onyx-015). Basic research provided several candidates for the liver metastasis-associated genes, including MMP7, DCC, CDC25B, E-cadherin, CD44, vascular endothelial growth factor, etc. There is an alternative approach to liver metastasis, which attempts to introduce a specific gene such as cytosine deaminase and TIMP-2 into the hepatocytes but not into the tumor itself. This concept is based on results showing that hepatocytes can incorporate genes more readily than cancer cells can. Recently, mutant virus therapy has been developed, which includes Onyx-015, adenovirus dl922-947, and mutant-type herpes simplex virus. These mutant types of virus specifically proliferate in the cancer cells and result in their lysis. In the future, development of gene delivery systems that are powerful and specific to cancer type is essential.

Also flagged:hereditary hemochromatosisHHironTfR2
Journal Article 2001-05-01 No Snippets Bosserhoff AK, Hellerbrand C, Buettner R.
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Hereditary hemochromatosis (HH) is an autosomal recessive disease in which increased iron absorption causes iron overload and irreversible tissue damage. As laboratory parameters for measuring HH lack specificity, and HH remains asymptomatic for a long time, methods for genetic screening are highly valuable. Mutations in two genes, hfe and TfR2, have recently been found to be responsible for HH. The mutation C282Y in the hfe gene is detected in 70-95% of German and Austrian HH patients. Mutations in the TfR2 gene have been detected only very recently, and results of larger epidemiological studies are not yet available. Molecular methods permit molecular diagnosis and genetic screening.

Also flagged:nucleosome-binding proteinHMGN2hereditary hemochromatosishemachromatosisGFPnucleus
Journal Article 2001-05-01 ✓ 5 Snippets Birger Y, Ito Y, West KL, Landsman D, Bustin M.
In-Text Gene Mentions

HMGN4, a newly discovered…

…discovered nuclear protein,HMGN4, that is closely…

…single approximately 2-kbHMGN4mRNA was found…

…tested; however, theHMGN4transcript was significantly…

…TheHMGN4protein could be…

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We describe a newly discovered nuclear protein, HMGN4, that is closely related to the canonical HMGN2 nucleosome-binding protein. The protein is encoded by an intronless gene, which, in humans, is located in the hereditary hemochromatosis [correction of hemachromatosis] region at position 6p21.3. A single approximately 2-kb HMGN4 mRNA was found to be expressed, in variable amounts, in all human tissues tested; however, the HMGN4 transcript was significantly less abundant than that of HMGN2. The HMGN4 protein could be detected in HeLa cells by Western analysis with an antibody elicited against a unique region of the protein. Transfection of HeLa cells with a plasmid expressing HMGN4-GFP indicated that the protein localizes to the nucleus. Our results expand the multiplicity of the HMGN protein family and increase the known cellular repertoire of nucleosome-binding proteins.

Also flagged:synovial sarcoma associated proteinSYTacute leukemia associated protein AF10synovial sarcomachromosomeSSX1
Journal Article 2001-05-01 ✓ 1 Snippet de Bruijn DR, dos Santos NR, Thijssen J, Balemans M, Debernardi S, Linder B, Young BD, Geurts van Kessel A.
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The synovial sarcoma associated protein SYT interacts with the acute leukemia associated protein AF10.

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As a result of the synovial sarcoma associated t(X;18) translocation, the human SYT gene on chromosome 18 is fused to either the SSX1 or the SSX2 gene on the X chromosome. Although preliminary evidence indicates that the (fusion) proteins encoded by these genes may play a role in transcriptional regulation, little is known about their exact function. We set out to isolate interacting proteins through yeast two hybrid screening of a human cDNA library using SYT as a bait. Of the positive clones isolated, two were found to correspond to the acute leukemia t(10;11) associated AF10 gene, a fusion partner of MLL. Confirmation of these results was obtained via co-immunoprecipitation of endogenous and exogenous, epitope-tagged, SYT and AF10 proteins from cell line extracts and colocalization of epitope-tagged SYT and AF10 proteins in transfected cells. Subsequent sequential mutation analysis revealed a highly specific interaction of N-terminal SYT fragments with C-terminal AF10 fragments. The N-terminal interaction domain of the SYT protein was also found to be present in several SYT orthologs and homologs. The C-terminal interaction domain of AF10 is located outside known functional domains. Based on these results, a model is proposed in which the SYT and AF10 proteins act in concert as bipartite transcription factors. This model has implications for the molecular mechanisms underlying the development of both human synovial sarcomas and acute leukemias.

Also flagged:ironporphyriaporphyria cutanea tardaalcohol abusehepatitis Cmetabolism
Journal Article 2001-05-01 ✓ 5 Snippets Skowron F, Bérard F, Grézard P, Wolf F, Morel Y, Perrot H.
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We analyzed the relationship between HFE mutations and biochemical abnormalities in porphyria cutanea tarda and the interaction with other triggering factors of porphyria cutanea tarda (alcohol abuse, hepatitis C, drugs).<h4>Patients and methods</h4>Hepatitis C, alcohol abuse, drug intake and HFE mutations were determined in 56 patients with porphyria cutanea tarda (44 men and 12 women).

Hepatatic cytolysis was linked to alcohol abuse and hepatitis C but not to HFE mutations.<h4>Discussion</h4>The frequencies of HFE mutations in Lyons France are halfway between Anglo-Saxon and Italian papers, highlighting the Celtic origin of C282Y mutation.

The aim of this work was to determine the frequency of the hemochromatosis gene (HFE) in 56 patients with porphyria cutanea tarda.

…[Role of thehemochromatosisgene in prophyria…

…frequency of thehemochromatosisgene (HFE) in…

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<h4>Background</h4>The cause of iron overload in prophyria cutanea tada is unknown. The aim of this work was to determine the frequency of the hemochromatosis gene (HFE) in 56 patients with porphyria cutanea tarda. We analyzed the relationship between HFE mutations and biochemical abnormalities in porphyria cutanea tarda and the interaction with other triggering factors of porphyria cutanea tarda (alcohol abuse, hepatitis C, drugs).<h4>Patients and methods</h4>Hepatitis C, alcohol abuse, drug intake and HFE mutations were determined in 56 patients with porphyria cutanea tarda (44 men and 12 women). Iron status was determined from transferrin saturation, serum iron, and serum ferritin. Liver metabolism was determined from liver chemistries: alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transpeptidase.<h4>Results</h4>Thirty-nine patients (69.4 p. 100) carried HFE mutations, 18 (32.1 p. 100) were H63D heterozygous, 4 (7.1 p. 100) were H63D homozygous, 9 (16 p. 100) C282Y heterozygous, 8 (14.2 p. 100) compound C282Y/H63D heterozygous and none were C282Y homozygous. Comparison between porphyria cutanea tarda with and without mutations showed that compound C282Y/H63D heterozygous status was significantly linked to iron overload: transferrin saturation=0.61 vs 0.39 (p=0.0001) and serum iron=32.9 vs 22.4 (p=0.0046). H63D homozygous status was linked to iron overload but non-significantly: transferrin sturatin=0.53 vs 0.39 (p=0.06). The class with high iron overload (transferrin saturation > 0.45) was not linked with triggering factors of porphyria cutanea tarda. Hepatatic cytolysis was linked to alcohol abuse and hepatitis C but not to HFE mutations.<h4>Discussion</h4>The frequencies of HFE mutations in Lyons France are halfway between Anglo-Saxon and Italian papers, highlighting the Celtic origin of C282Y mutation. Compound heterozygous and to a lesser degree H63D homozygous status explained the highest iron overload in our patients. This favors clinical expression of porphyria cutanea tarda. This iron overload due to HFE mutations is a new triggering factor of porphyria cutanea tarda independent of classical triggering factors: mutation of the erythrocytic uroporpyrinogen decarbocylase gene, alcohol abuse, hepatitis C, and drugs.

Also flagged:IL-1Bcancerinflammatory responseInterleukin 1Bpro-inflammatory cytokineaddiction
Journal Article 2001-05-01 ✓ 1 Snippet Hamajima N, Katsuda N, Matsuo K, Saito T, Ito LS, Ando M, Inoue M, Takezaki T, Tajima K.
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…transporter gene (5-HTT) 8 )…

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Recent studies suggest that smoking habit may relate to genetic traits. This study examines the association with a polymorphism (C-31T) of interleukin 1B (IL-1B), which encodes IL-1beta, a multifunctional pro-inflammatory cytokine. Since the T allele makes a TATA box, the allele is thought to be responsible for a higher potency of IL-1B expression, indicating that individuals harboring the T allele are prone to inflammation. The study subjects were two different populations; 241 non-cancer outpatients (118 males and 123 females) at a cancer hospital and 462 examinees (127 males and 335 females) of a health checkup program provided by a local government. Current smokers were 36.4% for the male outpatients, 9.8% for the female outpatients, 38.6% for the male examinees, and 5.6% for the female examinees. The sex-age-adjusted odds ratios of current smokers were calculated for the genotypes with the T allele relative to the CC genotype by an unconditional logistic model. The estimate was 0.45 (95% confidence interval, 0.21-0.97) for the outpatients, and 0.83 (0.42-1.61) for the examinees. Although not significant for the examinees, the observed associations suggest that this polymorphism may influence smoking behavior through an inflammatory response of the respiratory tract to cigarette smoke.

Also flagged:serotoninneurotismaffective disordersserotonin transporteranxietyneuroticism
Journal Article 2001-05-01 ✓ 3 Snippets Golimbet VE, Alfimova VM, Shcherbatykh TV, Abramova LI, Kaleda VG, Rogaev EI.
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Some studies associate the insertion/deletion polymorphism of the serotonin transporter (5-HTT) gene with anxiety-related personality traits in mentally healthy people, the short (s) allele being associated with a higher neuroticism score.

…the serotonin transporter (5-HTT) gene with anxiety-related…

…The5-HTTgenotype and neuroticism…

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Some studies associate the insertion/deletion polymorphism of the serotonin transporter (5-HTT) gene with anxiety-related personality traits in mentally healthy people, the short (s) allele being associated with a higher neuroticism score. The 5-HTT genotype and neuroticism score were established for 114 affective patients, 87 healthy relatives of endogenous psychosis patients, and for 156 mentally healthy people without familial psychiatric history. The effects of sex and age on the association between the two parameters was studied. Neuroticism proved to be not associated with the 5-HTT genotype.

Also flagged:Haemochromatosisironneoplasia
Journal Article 2001-05-01 ✓ 2 Snippets Bassett ML.
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Our ability to detect those predisposed to haemochromatosis is greatly enhanced by testing for HFE mutations.

…by testing forHFEmutations.…

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Our ability to detect those predisposed to haemochromatosis is greatly enhanced by testing for HFE mutations. Ironically, this diagnostic advance has led to some confusion regarding the criteria for diagnosis of haemochromatosis, with overreliance on genetic testing instead of investigations for iron overload. Because many people who are homozygous for the C282Y mutation, or compound heterozygous for the C282Y and H63D mutations, either do not express or only partially express the disease, it is essential to confirm a diagnosis of haemochromatosis on the basis of increased body iron stores. Liver biopsy remains the best method of confirming this and has an important role in the patient with either borderline iron overload or advanced disease. Persistent elevation of serum ferritin concentration in the absence of overt liver damage, inflammation or neoplasia, and estimation of mobilized body iron by repeated phlebotomy, are reasonable alternatives to liver biopsy. Although the precise definition of iron overload is debated, a diagnosis of haemochromatosis cannot be made without demonstrating increased body iron stores.

Also flagged:Ironpyruvate kinase deficiencyhereditary hemochromatosispyruvate kinasePK
Journal Article 2001-05-01 ✓ 5 Snippets Zanella A, Bianchi P, Iurlo A, Boschetti C, Taioli E, Vercellati C, Zappa M, Fermo E, Tavazzi D, Sampietro M.
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…Iron status andHFEgenotype in erythrocyte…

…editary hemochromatosis gene (HFE) in 34 pyruvate…

HFEgenotype was abnormal…

…with splenectomy andHFEgenotypes.…

…7 with wild-typeHFEgenotype) with at…

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We evaluated the iron status and searched for mutations C282Y and H63D in the hereditary hemochromatosis gene (HFE) in 34 pyruvate kinase (PK)-deficient patients from 29 unrelated families. Nine had received multiple transfusions. Thirteen of the 25 nontransfused patients displayed increased serum ferritin concentration, in the absence of conditions known to raise this parameter. HFE genotype was abnormal in 9 of 34 patients. The allele frequency was 1.8% for mutation 845G--> (C282Y) and 16.1% for mutation 187C-->G (H63D). Nontransfused subjects with abnormal genotype had serum ferritin and transferrin saturation values significantly higher than those with wild-type genotype. Of the 12 adult nontransfused patients with increased iron status parameters, 1 was C282Y homozygous, 1 compound heterozygous for C282Y and H63D, 3 H63D heterozygous, and 7 had a normal HFE genotype. Serum ferritin and transferrin saturation were not related to hemoglobin, reticulocytes, and bilirubin concentration. At multivariate analysis serum ferritin was independently associated with age and gender, but not with splenectomy and HFE genotypes. The retrospective evaluation of the iron status profile of 10 patients (3 with abnormal and 7 with wild-type HFE genotype) with at least 10 years follow-up showed that overt iron accumulation requiring iron chelation had occurred only in the 3 patients (2 of whom were splenectomized) with the mutated HFE gene.

Also flagged:ironchronic hepatitis Cmetabolism
Journal Article 2001-05-01 ✓ 1 Snippet Shiono Y, Hayashi H, Wakusawa S, Sanae F, Takikawa T, Yano M, Yoshioka K, Saito H.
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…H63D mutations ofHFEgene were analyzed…

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Information on the level of iron stores in chronic hepatitis C is clinically important because its reduction is technically simple and therapeutically effective. This study was performed to measure the levels of iron stores from the total amounts of hemoglobin removed during iron reduction therapy. The C282Y and H63D mutations of HFE gene were analyzed in 94 patients. All of the patients were negative for C282Y mutation. One patient was homozygous, and 4 patients were heterozygous for H63D mutation. The body iron stores and iron restoration rate were measured in 59 patients in serial courses of iron reduction therapy. Mean values of body iron stores in the two groups with and without H63D mutation were 890 and 606 mg, while those of iron restoration rate were 1.85 and 1.52 mg/day, respectively. None of the indices of iron metabolism were different from the reference values measured similarly in healthy subjects, suggesting that the iron deposition in chronic hepatitis C is limited to the liver, probably due to changes in the iron distribution in tissues.

Also flagged:testicular germ cell tumorsTesticular germ cell tumorTGCTtumortesticular cancerchromosome
Journal Article 2001-05-01 ✓ 1 Snippet Skotheim RI, Kraggerud SM, Fosså SD, Stenwig AE, Gedde-Dahl T, Danielsen HE, Jakobsen KS, Lothe RA.
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DCC

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Testicular germ cell tumor (TGCT) is the most common tumor type among adolescent and young adult males. Familial clustering and bilateral disease are suggestive of a genetic predisposition among a subgroup of these patients, but susceptibility genes for testicular cancer have not yet been identified. However, suggestive linkage between disease and genetic markers has been reported at loci on chromosome arms 3q, 5q, 12q, 18q, and Xq. We have analyzed primary familial/bilateral (n=20) and sporadic (n=27) TGCTs, including 28 seminomas and 19 nonseminomas, for allelic imbalance (AI) within the autosomal regions. DNA from all tumors were analyzed by fluorescent polymerase chain reaction of 22 polymorphic loci at 3q27-ter, 5q13-35.1, 12q21-ter, and 18q12--ter. All tumor genotypes were evaluated against their corresponding constitutional genotypes. The percentages of TGCTs with genetic changes at 3q, 5q, 12q, and 18q, were 79%, 36%, 53% and 43%, respectively. The frequencies at 3q and 12q in nonseminomas were significantly higher than in seminomas (P=.003 and P=.004). In order to evaluate changes at hemizygous Xq loci, five loci were analyzed by co-amplification with an autosomal reference marker known to reveal retained heterozygosity in the tumor DNA. Gain of Xq sequences was seen in more than 50% of the tumors. The degree of amplification varied among the loci in each of five tumors, and based on these breakpoints, a common region of overlapping gains was found at Xq28. No significant differences were found between the frequencies of genetic changes in familial/bilateral versus sporadic tumors, an observation speaking in disfavor of the existence of a single susceptibility gene for TGCT in any of the analyzed regions. Our data suggest that gain of genetic material at distal Xq and losses at 5q and 18q contribute to establishment of seminomas, whereas imbalances at 3q as well as gain at distal part of 12q are associated with further progression into nonseminomas.

Also flagged:breast cancersteroid receptorERThymidineprimary tumourtumour
Journal Article 2001-05-01 ✓ 2 Snippets Paradiso A, Serio G, Serio G, Fanelli M, Mangia A, Cellamare G, Schittulli F.
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In order to evaluate if breast cancer biological characteristics undergo significant menstrual and seasonal variations, we analysed in a consecutive series of 905 breast cancer patients, steroid receptor level (ER and PgR by DCC assay), proliferative activity (3H-Thymidine Labeling Index, 3H-TLI) and size of primary tumour in relation to calendar date and day of menstrual cycle at the time of the surgical procedure.

…and PgR byDCCassay), proliferative activity…

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In order to evaluate if breast cancer biological characteristics undergo significant menstrual and seasonal variations, we analysed in a consecutive series of 905 breast cancer patients, steroid receptor level (ER and PgR by DCC assay), proliferative activity (3H-Thymidine Labeling Index, 3H-TLI) and size of primary tumour in relation to calendar date and day of menstrual cycle at the time of the surgical procedure. For data analysis, the method of time series construction and classical spectral analyses with Bartlett Kolmogorov-Smirnov test for white noise (BKS test) was utilised. For what concerns menstrual variations, 3H-TLI showed a significant periodicity (t = 0.3146, p < 0.01 by BKS test) with peaks at day 12nd and day 18th; ER showed a significant periodicity (t = 0.3605, p < 0.01 by BKS test) with more evident peak at day 27th; PgR, a significant periodicity (t = 0.160, p = 0.05 by BKS test) with peaks at day 15th and day 24th, similar to that observed for tumour size (t = 0.19, p < 0.05 by BKS test). With respect to yearly fluctuations, 3H-TLI showed only a trend for a significant rhythm (t = 0.16, p = 0.06 by BKS test) with peaks in May and November; ER a significant periodicity (t = 0.2099, p < 0.05 by BKS test) with two evident peaks in January and April; also for PgR a significant periodicity (t = 0.3161, p < 0.05 by BKS test) was demonstrated with a peak in July; finally, tumour size showed a significant rhythm (t = 0.335, p < 0.01) paralleling 3H-TLI behaviour. Finally, the analysis of variance with interaction of menstrual and seasonal timings showed that only the seasonal timing was able to independently influence the 3H-TLI variations (3H-TLI higher in spring). We confirmed that breast biology has significant menstrual and seasonal variations and that the seasonality is probably the timing factor more relevant in periodicity determination.

Also flagged:mammary cancerOX-40 receptortumor necrosis factor receptorTNF-RCD4cell activation
Journal Article 2001-05-01 No Snippets Morris A, Vetto JT, Ramstad T, Funatake CJ, Choolun E, Entwisle C, Weinberg AD.
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The OX-40 receptor (OX-40R) is a member of the tumor necrosis factor receptor (TNF-R) superfamily that is expressed on activated CD4+ T cells. The OX-40R is a costimulatory molecule that induces CD4+ T cell activation when engaged by its ligand (OX-40 L; found on antigen presenting cells). In human and murine tumors, we have shown upregulation of the OX-40R on CD4+ T cells from tumor-infiltrating lymphocytes (TIL) and tumor-draining lymph node cells (TDLNC) but not on systemic CD4+ T cells, such as peripheral blood lymphocytes (PBL) or splenocytes. In order to examine potentially heightened anti-tumor immunity through enhanced costimulation when engaging OX-40R in vivo, we inoculated mice with a murine mammary cancer cell line (SM1) and then treated with a soluble form of the OX-40 L. Mice injected with a lethal inoculum of SM1 cells were given two intraperitoneal injections (days 3 and 7 post-inoculation) of 100 microg soluble OX-40 L. Seven of 28 treated mice survived the lethal tumor inoculum, as compared to one of 28 control mice, demonstrating a significant survival benefit with treatment (p = 0.0136, log rank analysis). Mice that did not develop tumor by day 90 were rechallenged; all remained tumor-free. Mice were also injected with a second mammary tumor line (4T1) and treated with OX-40L:Ig with similar therapeutic results. Activation of OX-40R+ CD4+ T cells during mammary cancer priming stimulated an antitumor immune response resulting in enhanced survival and protective anti-tumor immunity. These results should have practical applications for treatment modalities for patients with breast cancer.

Also flagged:Huntington's diseaseHDgenetic disorderdeathneurotrophic factorscaspase
Journal Article 2001-05-01 No Snippets Emerich DF.
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Huntington's disease (HD) is a devastating genetic disorder. Despite the absence of effective therapy, there has been an explosion in interest for developing treatment strategies aimed at lessening or preventing the neuronal death that occurs in this disease. In large part, the renewed interest in neuroprotective strategies has been spurred by our increasing understanding of the genetic and molecular events that drive the underlying neuropathology of HD. This escalating understanding of the biological underpinnings of HD is derived from several convergent sources represented by investigators with clinical, genetic, molecular, physiological and neurobehavioural backgrounds. The diversity of data being generated has, in turn, produced a unique time in HD research where an impressive number of potential therapeutics are coming to the forefront. This review outlines several of these possibilities including the use of intracerebrally delivered neurotrophic factors, pharmacologically altering cellular energy production, the use of antiglutamatergic drugs, the use of caspase inhibitors and inhibitors of protein aggregation. This review also touches on the interesting possibility of whether or not the neurodegeneration in HD is at least partially reversible in nature. All of these possibilities are highlighted in the context that HD is a neurodegenerative disorder in which genetic detection provides a clear and unequivocal opportunity for neuroprotection.

Also flagged:pbppenicillin
Journal Article 2001-05-01 No Snippets Yang F, Zhang Y, McGee L.
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<h4>Objective</h4>To investigate the population biology of Streptococcus pneumoniae carried by healthy children.<h4>Methods</h4>Drug resistant patterns and serotypes of 222 strains were determined. PFGE, BOX PCR and pbp fingerprint techniques were used to analyze the homology among strains.<h4>Results</h4>Among 222 nasopharyngeal isolates from 5 day-care centers, there were 32 penicillin intermediate Streptococcus pneumoniae (PISP, MIC 0.125 approximately 1 mg/L), and no penicillin resistant Streptococcus pneumoniae (PRSP, MIC >/= 2 mg/L) was found. The main serotypes of all strains were 23F (25.7%), 6A (13.1%), 19F (10.8%), and 6B (8.1%). The serotypes of PISP were mainly 23F (50%), 19A (15.6%) and 19F (15.6%). Among the 32 PISP strains, 8 BOX PCR clusters and 7 PFGE types were identified. The resistance patterns, serotypes, BOX PCR and pbp fingerprints of PFGE type A strains were highly consistent. In day care center (DCC) SY, the penicillin resistant rate was 31.8%, being much higher than the average level. Twenty of the 21 PISP strains isolated from this DCC belonged to PFGE type A or B.<h4>Conclusions</h4>The penicillin resistant rate of Streptococcus pneumoniae carried by healthy children in 5 DCCs of Shanghai was still low. However in one DCC, there could be a prevalence of some resistant clones which resulted in high penicillin resistant rate.

Metabolic liver disease.

Also flagged:Metabolic liver diseasediseases of thepathogenesismetabolic diseases ofacute liver failureWilson disease
Journal Article 2001-05-01 ✓ 1 Snippet Schilsky ML, Mistry P.
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…topics, Wilson disease,hemochromatosisand iron overload…

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The discovery of novel metabolic pathways and the genetic basis for diseases of the liver continues to yield new insights into the pathogenesis of inherited metabolic diseases of the liver, whereas the application of new technologies to their treatment continues to advance therapeutic options. This review of selected articles covers a wide range of subjects, from the identification of novel proteins and transport pathways to disease diagnosis and treatment of acute liver failure. Four selected topics, Wilson disease, hemochromatosis and iron overload disorders, alpha-1 antitrypsin disease, and exciting new therapeutic options for lysosomal storage diseases are the focus of this review.

Also flagged:nucleosomechromatinhistonesH2AH2Bhistone
Journal Article 2001-05-01 ✓ 1 Snippet Schnitzler GR.
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…of polynucleosomes lackinglinker histoneshistones from these…

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In vitro analysis of DNA in chromatin is often important for understanding mechanisms of regulation of transcription and other processes that occur on DNA. The basic unit of chromatin is the nucleosome core, containing two copies each of the core histones H2A, H2B, H3, and H4 to form a histone octamer that wraps 145 base pairs of DNA in a left-handed superhelix. In vivo, chromatin is associated with linker histones (such as H1), which facilitate the ordered packing of nucleosomes. This linker histone-containing particle is properly termed the nucleosome (or chromatosome), while the linker histone-free particle is the nucleosome core. Pure polynucleosome cores and histones can be readily isolated from mammalian tissue culture cells. This unit describes procedures for isolation and purification of nuclei, isolation of polynucleosomes lacking linker histones from these nuclei, isolation of pure populations of mono- and dinucleosome cores from oligonucleosome fractions, and isolation of core histones from purified nuclei. The methods presented here do not denature the histones, and may yield histones that are more active for in vitro assemblies.