Search results for "CYSTEINE"
showing 10 items of 550 documents
A simple high-performance liquid chromatography (HPLC) method for the measurement of pyridoxal-5-phosphate and 4-pyridoxic acid in human plasma.
2014
Abstract Background Low concentration of plasma pyridoxal-5-phosphate (PLP) is associated with hyperhomocysteinemia and inflammation. Most methods for the measurement of plasma PLP require large specimen volume and involve the use of toxic reagents. Methods We have developed a HPLC method for the measurement of PLP and 4-pyridoxic acid (4-PA) in plasma, which requires small specimen volume. The samples are prepared without adding any toxic reagents. Furthermore, we have examined whether intake of vitamin B 6 affects the concentration of plasma PLP and 4-PA. Results The coefficient of variation of the method was 6% and the recovery of the added vitamin in plasma was about 100%. The concentra…
Folate deficiencies and cardiovascular pathologies.
1998
Abstract Although folates are widely distributed in foods, folate deficiencies may be more frequent than expected because their true availability may be impaired due to their lability under various food cooking and processing conditions. Folate deficiency is frequently observed in elderly people, smokers, alcoholics and oral contraceptive users. It is also associated with the mutation leading to the thermolabile variant of N5, 10-methylenetetrahydrofolate reductase which is observed in about 10 % of the population. In addition to the essential role of the intracellular pool of polyglutamates in de novo biosynthesis of deoxyribonucleotides which allow cell growth and division, the reduced an…
Hypoxia Positively Regulates the Expression of pH-Sensing G-Protein–Coupled Receptor OGR1 (GPR68)
2016
Background & Aims: A novel family of proton-sensing G-proteinâcoupled receptors, including ovarian cancer G-proteinâcoupled receptor 1 (OGR1) (GPR68) has been identified to play a role in pH homeostasis. Hypoxia is known to change tissue pH as a result of anaerobic glucose metabolism through the stabilization of hypoxia-inducible factor-1α. We investigated how hypoxia regulates the expression of OGR1 in the intestinal mucosa and associated cells. Methods: OGR1 expression in murine tumors, human colonic tissue, and myeloid cells was determined by quantitative reverse-transcription polymerase chain reaction. The influence of hypoxia on OGR1 expression was studied in monocytes/macrophages and…
A Role for the β1-β2Loop in the Gating of 5-HT3Receptors
2005
Based on theTorpedoacetylcholine receptor structure, Unwin and colleagues (Miyazawa et al., 2003; Unwin, 2005) hypothesized that the transduction of agonist binding to channel gate opening involves a “pin-into-socket” interaction between αV46 at the tip of the extracellular β1-β2loop and the transmembrane M2 segment and M2-M3 loop. We mutated to cysteine the aligned positions in the 5-HT3Aand 5-HT3Bsubunit β1-β2loops K81 and Q70, respectively. The maximal 5-HT-activated currents in receptors containing 5-HT3A/K81C or 5-HT3B/Q70C were markedly reduced compared with wild type. Desensitization of wild-type currents involved fast and slow components. Mutant currents desensitized with only the f…
Assessment of the roles of LuxS, Autoinducer 2 and its precursor S-Ribosyl Homocysteine, in cell attachment during biofilm formation by Listeria mono…
2007
No abstract
Rat tyrosine kinase inhibitor shows sequence similarity to human α2-HS glycoprotein and bovine fetuin
1991
Human alpha 2-HS glycoprotein and bovine fetuin, abundant proteins of fetal plasma, are structural members of the fetuin family within the cystatin superfamily. They are characterized by the presence of two N-terminally located cystatin-like units and a unique C-terminal sequence segment not present in the other members of the cystatin superfamily. Search for related sequences revealed that the natural inhibitor of the insulin receptor tyrosine kinase [Auberger, Falquerho, Contreres, Pages, Le Cam, Rossi & Le Cam (1989) Cell (Cambridge, Mass.) 58, 631-640] shows sequence similarity to the mammalian fetuins. The sequence identity between rat tyrosine kinase inhibitor, human alpha 2-HS gl…
Dipeptides of S-Substituted Dehydrocysteine as Artzyme Building Blocks: Synthesis, Complexing Abilities and Antiproliferative Properties †
2021
Background: Dehydropeptides are analogs of peptides containing at least one conjugate double bond between α,β-carbon atoms. Its presence provides unique structural properties and reaction centre for chemical modification. In this study, the series of new class of dipeptides containing S-substituted dehydrocysteine with variety of heterocyclic moieties was prepared. The compounds were designed as the building blocks for the construction of artificial metalloenzymes (artzymes). Therefore, the complexing properties of representative compounds were also evaluated. Furthermore, the acknowledged biological activity of natural dehydropeptides was the reason to extend the study for antiproliferativ…
Carbocysteine reverses the effects of cigarette smoke and improves the effects of beclomethasone on the histone deacetylases in bronchial epithelial …
2015
Cigarette smoke exposure, increasing oxidative stress, may negatively affect histone deacetylase expression/activity. Histone deacetylase expression/activity and in particular HDAC2, HDAC3, and SIRT-1 may control inflammation, cell senescence and responses to corticosteroids. The effects of carbocysteine and of beclomethasone on the histone deacetylase expression/activity in human bronchial epithelial cells stimulated with cigarette smoke extracts (CSE) are largely unknown. This study was aimed to explore whether carbocysteine and beclomethasone, in a bronchial epithelial cell line (16-HBE) exposed to CSE, were able to modulate the expression/activity of HDAC2, HDAC3, and of SIRT-1. Methods…
Acetylcysteine therapy for chronic hepatitis C: are its effects synergistic with interferon alpha? A pilot study.
2008
This trial reports the 6-month results of a pilot study using lymphoblastoid interferon alpha (IFNalpha) and acetylcysteine (N-acetylcysteine) separately and in combination in patients with chronic hepatitis C, genotype 1b, who were nonresponders to previous treatment with recombinant IFNalpha alone.21 patients were randomly divided into three groups of seven each. Group A was treated with lymphoblastoid IFNalpha 6MU three times a week for 6 months; group B received the same schedule of lymphoblastoid IFNalpha as group A plus acetylcysteine 1200 mg/day per os in two administrations, and group C received only acetylcysteine 1200 mg/day per os in two administrations.Mean serum alanine aminotr…
Benigne Form der Osteopetrose
2001
Die Osteopetrose ist eine Erkrankung, bei der es zu Resorptionsstorungen des durch enchondrale Ossifikation gebildeten Knochens kommt. Die Ursache der Osteoklasteninsuffizienz ist nicht bekannt. In der Literatur wird ein vollstandiger Syntheseverlust der Zysteinprotease Kathepsin K als Atiologie der Resorptionsstorung diskutiert. Wir konnten in unserem Fallbericht bei der benignen Form der Osteopetrose eine Kathepsin-K-Expression osteoklastarer Zellen nachweisen. Weiterhin fanden wir in den osteoklastaren Zellen den Makrophagenmarker CD68, wobei sich in deren Nachbarschaft keine weiteren Zellen des mononuklearen Phagozytensystems darstellen liesen. Eine Hemmung der osteoklastaren Zellen dur…