BACKGROUND : The diagnosis of cholangiocarcinoma in patients with a biliary stricture without mass syndrome can be obtained by biliary brushing with a sensitivity of ~50 %. We performed a multicenter randomized crossover trial comparing the aggressive Infinity brush with the standard RX Cytology Brush. The aims were to compare sensitivity for cholangiocarcinoma diagnosis and cellularity obtained.
View Article and Find Full Text PDFEndoscopic mucosal resection (EMR) with snare is the recommended technique to resect non-invasive colorectal neoplastic lesions between 10 and 30 mm in diameter. The objective of EMR is to resect completely the neoplastic tissue en bloc and preferably with free margins (R0), avoiding recurrences. Anchoring the tip of the snare in the submucosa is a technical trick that allows snare sliding to be reduced and larger pieces to be caught.
View Article and Find Full Text PDFTranscriptomic genome-wide analyses demonstrate massive variation of alternative splicing in many physiological and pathological situations. One major challenge is now to establish the biological contribution of alternative splicing variation in physiological- or pathological-associated cellular phenotypes. Toward this end, we developed a computational approach, named "Exon Ontology," based on terms corresponding to well-characterized protein features organized in an ontology tree.
View Article and Find Full Text PDFPatients with mutations in MMACHC have the autosomal recessive disease of cobalamin metabolism known as cblC. These patients are unable to convert cobalamin into the two active forms, methylcobalamin and adenosylcobalamin and consequently have elevated homocysteine and methylmalonic acid in blood and urine. In addition, some cblC patients have structural abnormalities, including congenital heart defects.
View Article and Find Full Text PDFVitamin B(12) (cobalamin, Cbl) is required for cellular metabolism. It is an essential coenzyme in mammals for two reactions: the conversion of homocysteine to methionine by the enzyme methionine synthase and the conversion of methylmalonyl-CoA to succinyl-CoA by the enzyme methylmalonyl-CoA mutase. Symptoms of Cbl deficiency are hematological, neurological and cognitive, including megaloblastic anaemia, tingling and numbness of the extremities, gait abnormalities, visual disturbances, memory loss and dementia.
View Article and Find Full Text PDFOrgan-specific birth defects are seen in patients with some inborn errors of vitamin B(12) metabolism. To determine whether three mouse genes, whose human counterparts are associated with isolated methylmalonic aciduria (Mmaa, Mmab and Mut), show tissue-specific expression during organogenesis, we used in situ hybridization to characterize their pattern of expression in wild type embryos and placentas at embryonic days (E) E10.5, E11.
View Article and Find Full Text PDFBackground & Aims: Folate and cobalamin are methyl donors needed for the synthesis of methionine, which is the precursor of S-adenosylmethionine, the substrate of methylation in epigenetic, and epigenomic pathways. Methyl donor deficiency produces liver steatosis and predisposes to metabolic syndrome. Whether impaired fatty acid oxidation contributes to this steatosis remains unknown.
View Article and Find Full Text PDFCardiomyopathies occur by mechanisms that involve inherited and acquired metabolic disorders. Both folate and vitamin B12 deficiencies are associated with left ventricular dysfunction, but mechanisms that underlie these associations are not known. However, folate and vitamin B12 are methyl donors needed for the synthesis of S-adenosylmethionine, the substrate required for the activation by methylation of regulators of energy metabolism.
View Article and Find Full Text PDFObjective: The ankle brachial index (ABI) is an indicator of lower extremity peripheral arterial disease (PAD) and a predictor of atherothrombosis. ApoA-I and HDL are associated with PAD, in humans. Homocysteine influences the liver expression of ApoA-I and decreases its blood level and HDL in genetic mice models.
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