24 research outputs found

    Evolutionary Pathways of the Calcitonin (CALC) Genes

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    Recombinant DNA techniques have made it possible to establish the structure of various genes encoding polypeptide hormones. Comparison of nucleotide sequences of the calcitonin (CALC) genes in man has revealed surprising similarities and variations. These findings and the homologies among the sequences in different species offered an opportunity for speculation about relationships between these genes and about their evolutionary origin. The first gene (CALC-I) directing the synthesis of calcitonin (CT) or CT gene-related peptide (CGRP) comprises six exons and gives rise to two mRNAs by an alternative RNA-processing mechanism. The homology between CGRP and CT reflects their common origin. The human genome contains a second gene (CALC-II) that is structurally related to the CALC-I gene. The CALC-II RNA transcripts do not appear to be differentially processed, as only preproCGRP-II mRNA and not preproCT-II is detected. The first and second CTI CGRP genes probably have evolved from a common ancestor gene early in evolution. Meanwhile, a third genomic locus containing nucleotide sequences highly homologous to exons 2 and 3 of both CALC genes was detected and probably generated by duplication of a part of CALC-II. This locus is not likely to encode a CT- or CGRP-related polypeptide hormone. The CALC genes and this last (pseudo) gene are located on the short arm of chromosome 11. Recently, islet or insulinoma-amyloid polypeptide (IAPP) was isolated as a major constituent of amyloid present in human insulinoma and in pancreatic islet amyloid in noninsulin-dependent diabetes mellitus. lAPP shows 46% amino acid sequence homology with human CGRP-II. In contrast to the CALC-genes, the human IAPP gene is located on chromosome 12. All these findings have provided insight into the mechanisms underlying the increasing diversity of polypeptide hormones

    Relationship between pernicious anaemia and gastric neuroendocrine cell disorders

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    The incidence of gastric carcinoid tumours is increasing. This rise is probably due to the number of gastroscopies and improved histological techniques. The majority (65%) of these gastric tumours is associated with chronic atrophic gastritis and pernicious anaemia. In this article two patients are presented, one with pernicious anaemia and gastric neuroendocrine cell hyperplasia and one with pernicious anaemia and multiple gastric carcinoids. These neuroendocrine cell disorders have a relatively favourable prognosis. Therefore, a wait-and-see policy was preferred. The pathogenesis, clinical symptoms, diagnosis, prognosis and treatment of these different neuroendocrine cell manifestations are discussed. We recommend performing a gastroscopy at the time of diagnosis for young patients with pernicious anaemia, and whenever abdominal problems, unexplained weight loss or aggravation of the anaemia arise

    Bone formation in cases of delayed fracture union and pseudarthrosis

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    No beneficial effects of amantadine in treatment of chronic hepatitis C patients.

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    BACKGROUND: Benefit of adding amantadine to antiviral therapy for hepatitis C is controversial. AIMS: We aimed to examine whether such policy enhances sustained viral response in treatment-naive patients. METHODS: 297 naive hepatitis C patients were randomized for treatment with amantadine 200mg or placebo, combined with weight-based ribavirin and 12-day high-dose interferon alpha-2b induction therapy, followed by PEG-interferon alpha-2b (1.5 microg/kg/week up to 26 weeks and thereafter, 1.0 microg/kg/week until week 52). Treatment was discontinued if hepatitis C virus (HCV) RNA was positive at week 24. RESULTS: 49% of patients were (former) drug users. Genotype 1 occurred in 45%, high viral load in 70% and severe fibrosis/cirrhosis in 32%, without differences between amantadine or placebo groups. 90 patients prematurely discontinued treatment, mainly because of grade 3 or 4 toxicity. Intention-to-treat analysis revealed sustained viral response in 47% and 51% of amantadine and placebo groups (p=0.49). Amantadine did not enhance sustained viral response in patients with genotype 1 or high viral load nor did it improve primary non-response, breakthrough or relapse rates. Genotype non-1 and lower pre-treatment gamma GT levels were independent predictors for sustained viral response. CONCLUSION: Adding amantadine to antiviral therapy of previously untreated chronic hepatitis C patients has no beneficial effects

    Sofosbuvir plus simeprevir for the treatment of HCV genotype 4 patients with advanced fibrosis or compensated cirrhosis is highly efficacious in real life

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    Chronic hepatitis C virus (HCV) infection is a major cause of chronic liver disease and liver-related death. Recently, multiple regimens of different direct-acting antiviral agents (DAAs) have been registered. Although treatment with sofosbuvir (SOF) and simeprevir (SMV) is registered for the treatment of genotype 4 patients in some countries, data on efficacy of this combination are lacking. We aimed to assess the efficacy of SOF and SMV with or without RBV during 12 weeks in a real-life cohort of genotype 4 HCV patients. A retrospective multicentre observational study was conducted in 4 hospitals in Amsterdam, the Netherlands, including patients with advanced liver fibrosis or liver cirrhosis treated with SOF plus SMV with or without RBV during 12 weeks for a genotype 4 chronic HCV infection from 1 January 2015 to 1 August 2015. Sustained viral response (SVR) was established at week 12 after end of treatment. A total of 53 patients with genotype 4 HCV infection, treatment naïve and experienced, were included. SVR was achieved in 49 of 53 patients (92%). The four failures all had a virological relapse and did not receive ribavirin. Three were nonresponder to earlier interferon-based treatment, and one was treatment naive. In this real-life cohort of patients with HCV genotype 4 infection and advanced liver fibrosis/cirrhosis, we show that treatment with SOF and SMV is effective. The addition of RBV could be considered in treatment-experienced patients as recommended in guideline
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