627 research outputs found

    Frequent k- ras -2 mutations and p16INK4Amethylation in hepatocellular carcinomas in workers exposed to vinyl chloride

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    Vinyl chloride (VC) is a know animal and human carcinogen associated with liver angiosarcomas (LAS) and hepatocellular carcinomas (HCC). In VC-associated LAS mutations of the K- ras -2 gene have been reported; however, no data about the prevalence of such mutations in VC associated HCCs are available. Recent data indicate K- ras -2 mutations induce P16 methylation accompanied by inactivation of the p16 gene. The presence of K- ras -2 mutations was analysed in tissue from 18 patients with VC associated HCCs. As a control group, 20 patients with hepatocellular carcinoma due to hepatitis B (n = 7), hepatitis C (n = 5) and alcoholic liver cirrhosis (n = 8) was used. The specific mutations were determined by direct sequencing of codon 12 and 13 of the K- ras -2 gene in carcinomatous and adjacent non-neoplastic liver tissue after microdissection. The status of p16 was evaluated by methylation-specific PCR (MSP), microsatellite analysis, DNA sequencing and immunohistochemical staining. All patients had a documented chronic quantitated exposure to VC (average 8883 ppmy, average duration: 245 months). K- ras -2 mutations were found in 6 of 18 (33%) examined VC-associated HCCs and in 3 cases of adjacent non-neoplastic liver tissue. There were 3 G → A point mutations in the tumour tissue. All 3 mutations found in non-neoplastic liver from VC-exposed patients were also G → A point mutations (codon 12- and codon 13-aspartate mutations). Hypermethylation of the 5′ CpG island of the p16 gene was found in 13 of 18 examined carcinomas (72%). Of 6 cancers with K- ras -2 mutations, 5 specimens also showed methylated p16. Within the control group, K- ras -2 mutation were found in 3 of 20 (15%) examined HCC. p16 methylation occurred in 11 out of 20 (55%) patients. K- ras -2 mutations and p16 methylation are frequent events in VC associated HCCs. We observed a K- ras -2 mutation pattern characteristic of chloroethylene oxide, a carcinogenic metabolite of VC. Our results strongly suggest that K- ras -2 mutations play an important role in the pathogenesis of VC-associated HCC. © 2001 Cancer Research Campaignhttp://www.bjcancer.co

    Applications of the ACGT Master Ontology on Cancer

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    In this paper we present applications of the ACGT Master Ontology (MO) which is a new terminology resource for a transnational network providing data exchange in oncology, emphasizing the integration of both clinical and molecular data. The development of a new ontology was necessary due to problems with existing biomedical ontologies in oncology. The ACGT MO is a test case for the application of best practices in ontology development. This paper provides an overview of the application of the ontology within the ACGT project thus far

    Free triiodothyronine (T3) is negatively associated with fasting ghrelin serum levels in a population sample of euthyroid subjects

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    Purpose: Ghrelin is an orexigenic peptide hormone secreted in times of stress and hunger. It is deeply involved in the regulation of metabolism and energy homeostasis, promoting energy intake and inhibiting energy expenditure on a metabolic level. In this regard, it has in many ways antagonistic effect on the thyroid hormones, which increase metabolism and thus energy expenditure. While there is reasonable evidence of a negative association between ghrelin and hormones of the hypothalamic-pituitary-thyroid (HPT-) axis from studies in patients with thyroid dysfunction and small intervention studies, large-scale studies in healthy subjects are lacking. Therefore, we studied the relationship between total ghrelin serum levels and serum levels of the thyroid hormones in a large sample of euthyroid subjects. Methods: Total ghrelin, thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were determined after an overnight fast in 1666 subjects participating in a population-based cross-sectional study ('LIFE') including 10,000 adults. 1012 subjects were included in this analysis. Multiple linear regression analyses were performed. Results: FT3 was negatively associated with serum ghrelin; total sample: β = - 0.0001, p < 0.001; men: β = - 0.0002, p = 0.013; women: β = - 0.0001, p = 0.010, adjusted for age, BMI, alcohol consumption, serum levels of TSH and fT4 and smoking status. No associations were found between ghrelin serum levels and serum levels of fT4 or TSH. Conclusion: This is to date the largest study investigating the relationship between total serum ghrelin and thyroid hormones. The results point to a complex interaction and should initiate further research

    Rejets radioactifs et environnement du CERN en 2003

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    La radioactivité de l’environnement autour de l’Organisation Européenne pour la Recherche Nucléaire (CERN) et les doses de rayonnements qui en résultent pour la population avoisinante sont contrôlées par la Commission de Sûreté du CERN et de manière indépendante par les autorités compétentes des deux Etats Hôtes, l’Institut de Radioprotection et de Sûreté Nucléaire (IRSN) côté France et l’Office Fédéral de la Santé Publique (OFSP) côté Suisse. Dans ce rapport, les résultats de mesures concernent en particulier le territoire suisse. L’ensemble des mesures effectuées en 2003 prouve que le fonctionnement des installations du CERN était sans conséquence radiologique sur l’environnement et la population. Le contrôle des émissions montre que les rejets effectifs se situent également en 2003 nettement en dessous des limites réglementaires. Ce constat est confirmé par le contrôle des immissions dans l’environnement. Le CERN a bien respecté en 2003 comme dans les années précédentes la valeur directrice de dose liée à la source fixée à 0.3 mSv/an. L’impact réel représente en fait moins de 10% de cette valeur, comme l’indique l’estimation pour le groupe critique, qui est de l’ordre de 0.03 mSv/an

    Association between self-rating depression scores and total ghrelin and adipokine serum levels in a large population-based sample

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    Background: Ghrelin and the adipokines leptin and adiponectin have been suggested to be involved in mood and anxiety regulation and to be altered in affective disorders. However, studies investigating the association between ghrelin, leptin and adiponectin and depressive symptomatology are scarce but might contribute to a better understanding of their involvement in mood regulation. We thus aimed investigating the association between depressive symptomatology and total ghrelin as well as leptin and adiponectin serum levels in a large population-based sample. Methods: Total serum ghrelin, adiponectin and leptin levels were determined in 1666 subjects of a population-based cross-sectional study (“LIFE”). The Center for Epidemiological Studies Depression Scale (CES-D) and the Inventory of Depressive Symptoms – Self Rating (IDS-SR) were administered. Multiple linear regression analyses were conducted to examine the association between total serum ghrelin, leptin and adiponectin and the intensity of depressive symptoms. Results: In the total sample (n = 1,092), neither ghrelin nor leptin or adiponectin serum levels showed a significant association with CES-D or IDS-SR sum scores (N = 1,092) or in depressed/non-depressed subjects. Leptin serum levels showed a significantly positive association with IDS-SR sum scores in elderly men (≥60 years; β = 0.122, 95% CI: 0.009; 0.236; p = 0.035). Conclusion: Our study suggests that peripheral levels of ghrelin and adipokines in a cross-sectional study design might not be sufficient to measure their involvement in depression, suggesting that associations are more complex and multi-layered. Copyright © 2022 Wittekind, Kratzsch, Biemann, Mergl, Riedel-Heller, Witte, Villringer and Kluge

    Sowing the seeds of doubt: a narrative review on metacognitive training in schizophrenia

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    Abstract not availableSteffen Moritz, Christina Andreou, Brooke C. Schneider, Charlotte E. Wittekind, Mahesh Menon, Ryan P. Balzan, Todd S. Woodwar

    Biological activity differences between TGF-β1 and TGF-β3 correlate with differences in the rigidity and arrangement of their component monomers

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    [Image: see text] TGF-β1, -β2, and -β3 are small, secreted signaling proteins. They share 71–80% sequence identity and signal through the same receptors, yet the isoform-specific null mice have distinctive phenotypes and are inviable. The replacement of the coding sequence of TGF-β1 with TGF-β3 and TGF-β3 with TGF-β1 led to only partial rescue of the mutant phenotypes, suggesting that intrinsic differences between them contribute to the requirement of each in vivo. Here, we investigated whether the previously reported differences in the flexibility of the interfacial helix and arrangement of monomers was responsible for the differences in activity by generating two chimeric proteins in which residues 54–75 in the homodimer interface were swapped. Structural analysis of these using NMR and functional analysis using a dermal fibroblast migration assay showed that swapping the interfacial region swapped both the conformational preferences and activity. Conformational and activity differences were also observed between TGF-β3 and a variant with four helix-stabilizing residues from TGF-β1, suggesting that the observed changes were due to increased helical stability and the altered conformation, as proposed. Surface plasmon resonance analysis showed that TGF-β1, TGF-β3, and variants bound the type II signaling receptor, TβRII, nearly identically, but had small differences in the dissociation rate constant for recruitment of the type I signaling receptor, TβRI. However, the latter did not correlate with conformational preference or activity. Hence, the difference in activity arises from differences in their conformations, not their manner of receptor binding, suggesting that a matrix protein that differentially binds them might determine their distinct activities

    Survival of non-Western first generations immigrants with stomach cancer in North East Netherlands

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    Background: Isolated groups, such as first generation non-Western immigrants, are at risk for suboptimal utilisation of the health care system resulting in a worse outcome. Methods: From 1989 to 2007, all patients with stomach cancer were selected from the Comprehensive Cancer Centre North-East cancer registry. Associations between country of birth and patient, tumour and treatment characteristics were determined using χ2 analysis. Relative survival analysis was used to estimate relative excess risk of dying according to country of birth (non-Western vs Western). Results: After adjusting for confounding factors (patient, tumour and treatment related), the risk of dying was lower for first generation non-Western immigrants (relative excess risk 0.55, 95% confidence interval 0.43–0.70) compared with Western patients. Conclusion: Although the better survival of first generation non-Western immigrants with stomach cancer remains unexplained, it argues against accessibility problems within the Dutch health care syste
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