Search results for "Proline"
showing 10 items of 183 documents
Translational adaptation to heat stress is mediated by RNA 5‐methylcytosine in Caenorhabditis elegans
2021
Abstract Methylation of carbon‐5 of cytosines (m5C) is a post‐transcriptional nucleotide modification of RNA found in all kingdoms of life. While individual m5C‐methyltransferases have been studied, the impact of the global cytosine‐5 methylome on development, homeostasis and stress remains unknown. Here, using Caenorhabditis elegans, we generated the first organism devoid of m5C in RNA, demonstrating that this modification is non‐essential. Using this genetic tool, we determine the localisation and enzymatic specificity of m5C sites in the RNome in vivo. We find that NSUN‐4 acts as a dual rRNA and tRNA methyltransferase in C. elegans mitochondria. In agreement with leucine and proline bein…
Highly enantioselective synthesis of fluorinated gamma-amino alcohols through proline-catalyzed cross-Mannich reaction.
2005
A new, simple route for the synthesis of fluorinated beta-alkyl gamma-amino alcohols in optically pure form in only two steps and featuring proline catalysis from inexpensive and readily available starting materials is described. The applied strategy allows for the introduction of diversity into both the beta-fluoroalkyl and alpha-alkyl groups of these compounds. [reaction: see text]
Poly-Gly Region Regulates the Accessibility of Metal Binding Sites in Snake Venom Peptides
2022
It is supposed that the presence of poly-His regions in close proximity to poly-Gly domains in snake venoms is related to their biological activity; poly-His/poly-Gly (pHpG) peptides inhibit the activity of metalloproteinases during venom storage via the chelation metal ions, necessary for their proper functioning. This work shows that only the histidyl residues from the N-terminal VDHDHDH motif (but not from the poly-His tag) were the primary Zn(II) binding sites and that the poly-Gly domain situated in the proximity of a central proline residue may play a regulatory role in venom gland protection. The proline induces a kink of the peptide, resulting in steric hindrance, which may modulate…
Investigation of the Enantioselectivity Observed in Epoxidation Reactions Catalysed by Bis‐Strapped Chiral Porphyrins Derived from L ‐Proline
2002
The enantiomeric excesses obtained during the epoxidation reactions of p-chlorostyrene or 1,2-dihydronaphthalene catalysed by two different series of chiral porphyrins are reported. An attempt is made to correlate the enantioselectivity with the steric hindrance generated by the straps of these catalysts. It is shown that this steric hindrance is influenced by the nature of the strap and that it can be approximated. Additionally, the same strap is tethered in two different fashions on each side of the porphyrin, leading to either D2- or C2-symmetrical catalysts, for which the two sides are identically functionalised.
Triple therapy in treatment-experienced patients with HCV-cirrhosis in a multicentre cohort of the French Early Access Programme (ANRS CO20-CUPIC) – …
2013
International audience; Background & AimsIn phase III trials, the safety profile of triple therapy (pegylated interferon/ribavirin with boceprevir or telaprevir) seems to be similar in HCV treatment-experienced cirrhotic and non-cirrhotic patients, but few cirrhotics were included. We report the week 16 safety and efficacy analysis in a cohort of compensated cirrhotics treated in the French Early Access Programme.Methods674 genotype 1 patients, prospectively included, received 48 weeks of triple therapy. The analysis is restricted to 497 patients reaching week 16.ResultsA high incidence of serious adverse events (40.0%), and of death and severe complications (severe infection or hepatic dec…
Effectiveness of telaprevir or boceprevir in treatment-experienced patients with HCV genotype 1 infection and cirrhosis. : Triple therapy in HCV geno…
2014
International audience; BACKGROUND & AIMS: We investigated the effectiveness of the protease inhibitors peginterferon and ribavirin in treatment-experienced patients with hepatitis C virus (HCV) genotype 1 infection and cirrhosis. METHODS: In the Compassionate Use of Protease Inhibitors in Viral C Cirrhosis study, 511 patients with HCV genotype 1 infection and compensated cirrhosis who did not respond to a prior course of peginterferon and ribavirin (44.3% relapsers or patients with viral breakthrough, 44.8% partial responders, and 8.0% null responders) were given either telaprevir (n = 299) or boceprevir (n = 212) for 48 weeks. We assessed percentages of patients with sustained viral respo…
Performance of two HCV RNA assays during protease inhibitor-based triple therapy in patients with advanced liver fibrosis and cirrhosis.
2014
Introduction: On-treatment HCV RNA measurements are crucial for the prediction of a sustained virological response (SVR) and to determine treatment futility during protease inhibitor-based triple therapies. In patients with advanced liver disease an accurate risk/benefit calculation based on reliable HCV RNA results can reduce the number of adverse events. However, the different available HCV RNA assays vary in their diagnostic performance. Aim: To investigate the clinical relevance of concordant and discordant results of two HCV RNA assays during triple therapy with boceprevir and telaprevir in patients with advanced liver fibrosis/cirrhosis. Methods: We collected on-treatment samples of 1…
385 MOLECULAR STAGES OF PDGFB DRIVEN LIVER FIBROSIS: LESONS FROM A TRANSGENIC MOUSE MODEL
2012
underlying pathomechanisms is hampered by the lack of a suitable animal model. To circumvent this problem, we studied hepcidinknockout (KO) mice as a model of iron-overload associated liver disease. Methods: 6 and 12 month-old hepcidin-KO and -wild type (WT) mice fed 3% iron carbonyl-containing diet (Fe-diet) since four weeks of age were compared to age-matched WT and KO animals kept on standard diet. The liver phenotype was quantified serologically as well as morphometrically based on hematoxylin & eosin, Prussian blue and Sirius red stainings. Liver iron content was determined by atomic mass absorption. Liver fibrosis development was determined by collagen RT-PCR and hydroxyproline assay.…
The synthesis of SNAT2 transporters is required for the hypertonic stimulation of system A transport activity
2004
AbstractIn cultured human fibroblasts incubated under hypertonic conditions, the stimulation of system A for neutral amino acid transport, associated to the increased expression of the mRNA for SNAT2 transporter, leads to an expanded intracellular amino acid pool and to the recovery of cell volume. A protein of nearly 60 kDa, recognized by an antiserum against SNAT2, is increased both in the pool of biotinylated membrane proteins and in the total cell lysate of hypertonically stressed cells. The increased level of SNAT2 transporters in hypertonically stressed cells is confirmed by immunocytochemistry. DRB, an inhibitor of transcription, substantially inhibits the increase of SNAT2 proteins …
Using NMR in saliva to identify possible biomarkers of glioblastoma and chronic periodontitis
2018
Nowadays there is increasing interest in identifying-and using-metabolites that can be employed as biomarkers for diagnosing, treating and monitoring diseases. Saliva and NMR have been widely used for this purpose as they are fast and inexpensive methods. This case-control study aimed to find biomarkers that could be related to glioblastoma (GBL) and periodontal disease (PD) and studied a possible association between GBL and periodontal status. The participants numbered 130, of whom 10 were diagnosed with GBL and were assigned to the cases group, while the remaining 120 did not present any pathology and were assigned to the control group. On one hand, significantly increased (p < 0.05) meta…