Search results for "actin"
showing 10 items of 1375 documents
Direct-acting antiviral agents and risk of Hepatocellular carcinoma: Critical appraisal of the evidence
2021
Direct-acting antivirals (DAAs) revolutionized the treatment of chronic HCV-related disease achieving high rates of sustained virological response (SVR), even in advanced cirrhosis, with modest contraindications and a low rate of adverse events. However, the risk of hepatocellular carcinoma (HCC) persists due to the underlying chronic liver disease, both in patients with and without history of HCC. Although some initial studies reported a presumptive high risk of HCC development after DAA therapy, more recent observational studies denied this hypothesis. The residual risk for HCC occurrence after HCV eradication seems being progressively reduced with time after SVR. Data on recurrence of HC…
Comparative diazinon toxicity in guppy and zebra fish: Different role of oxidative metabolism
1993
Guppies pretreated with 1.1 μmol/L diazinon (0.5 times the LC50 with the guppy) for 7 d were less susceptible to the toxicity of the compound. The LC50 in these fish was about five times higher than that in nonpretreated animals. The lethal body burden and the slope of the concentration-response curve of diazinon in pretreated guppies were similar to those in zebra fish. The 7-d pretreatment of zebra fish with 12 μmol/L diazinon (0.5 times the LC50 with the zebra fish) did not affect the susceptibility of this species to diazinon. The pretreatment of guppies resulted in a strong inhibition of the formation of diazoxon and pyrimidinol during incubations of diazinon with the hepatic postmitoc…
Significance of Various Enzymes in the Control of Mutagenic and Carcinogenic Metabolites Derived from Aromatic Structures
1984
One important early contribution to the control of chemical carcinogenesis is provided by the enzyme pattern responsible for the generation and disposition of reactive metabolites. Especially well studied is the important group of enzymes responsible for the control of reactive epoxides. Many natural as well as man-made foreign compounds, including Pharmaceuticals, possess olefinic or aromatic double bonds. Such compounds can be transformed to epoxides by microsomal monooxygenases present in very many mammalian organs. By virtue of their electrophilic reactivity such epoxides may spontaneously react with nucleophilic centers in the cell and thus covalently bind to DNA, RNA, and protein. Su…
Multiple activation pathways of benzene leading to products with varying genotoxic characteristics.
1989
Abstract Benzene and 13 potential metabolites were investigated for genotoxicity in Salmonella typhimurium and V79 Chinese hamster cells. In the presence of NADPH-fortified hepatic postmitochondrial fraction (S9 mix), benzene reverted his- S. typhimurium strains. The effect was strongest in strain TA1535. Among the potential metabolites, only the trans-1,2-dihydrodiol, in the presence of S9 mix, and the diol epoxides, in the presence and absence of S9 mix, proved mutagenic in this strain. The anti-diol epoxide was more potent than the syn-diastereomer. Both enantiomers of the anti-diastereomer showed similar activities. S9 mix did not appreciably affect the mutagenicity of the anti-diol epo…
A Newly-Detected Reductase fromRauvolfiaCloses a Gap in the Biosynthesis of the Antiarrhythmic Alkaloid Ajmaline
2002
A new enzyme, 1,2-dihydrovomilenine reductase (E.C. 1.3.1), has been detected in Rauvolfia cell suspension cultures. The enzyme specifically converts 2beta( R)-1,2-dihydrovomilenine through an NADPH-dependent reaction into 17-O-acetylnorajmaline, a close biosynthetic precursor of the antiarrhythmic alkaloid ajmaline from Rauvolfia. A five-step purification procedure using SOURCE 30Q chromatography, hydroxyapatite chromatography, 2',5'-ADP Sepharose 4B affinity chromatography and ion exchange chromatography on DEAE Sepharose and Mono Q delivered an approximately 200-fold enriched enzyme in a yield of approximately 6%. SDS-PAGE showed an M r for the enzyme of approximately 48 kDa. Optimum pH …
Effect of Streptomyces coelicolor M145 cell immobilization on actinorhodin production
2016
Non previsto
First results on dark matter annihilation in the Sun using the ANTARES neutrino telescope
2013
A search for high-energy neutrinos coming from the direction of the Sun has been performed using the data recorded by the ANTARES neutrino telescope during 2007 and 2008. The neutrino selection criteria have been chosen to maximize the selection of possible signals produced by the self-annihilation of weakly interacting massive particles accumulated in the centre of the Sun with respect to the atmospheric background. After data unblinding, the number of neutrinos observed towards the Sun was found to be compatible with background expectations. The 90% CL upper limits in terms of spin-dependent and spin-independent WIMP-proton cross-sections are derived and compared to predictions of two sup…
Early Aptian corals from Peñascal (Bilbao, N Spain)
2020
From two horizons in the lower Aptian Peñascal limestone Formation south of Bilbao 22 coral species are reported. The corals belong to the scleractinian families Actinastraeidae, Eugyridae, Haplaraeidae, Latomeandridae, and Solenocoeniidae, and the octocorallian family Helioporidae. The stratigraphic distribution of the species lies between the Berriasian to Cenomanian, but most species have a distribution between the Barremian and Albian. The faunas show most palaeobiogeographical relationship to faunas from the Hauterivian to Albian of the European Boreal, the Western Atlantic and the Western Tethys.
Les ostracodes paleogenes du Togo: Taxonomie, biostratigraphie, apports dans l'organisation et l'évolution du bassin
1989
Paleogene ostracodes (P5 to P9/P10) from Togo include 59taxonomic units in several wells and one outcrop (Tabligbo). One new genus: Afranticythereis and eight new species are erected: Actinocythereis lomensis, Buntonia klologoensis, Buntonia parasemitecta, Hermanites regulosa, Leguminocythereis isobopaensis, Paraplatycosia dinglei, Poularia neokoldaensis, Soudanella seddohi.. The vertical succession of ecological zones ECO1 to ECO5 is related to a rythmic sequence: open facies followed by a restricted one. The first two (Upper Paleocene/Lower Eocene boundary) are equivalent to the ecological zone Z1 recognized from Mauritania to Guinea. The next two (ECO3/ECO4: Lower/Middle Eocene) should b…
Acanthochaetetidae (Hadromerida, Demospongiae) fromthe Coniacian of Vera de Bidasoa (basque pyrénées, Northern Spain)
1986
Abstract Acanthochaetetes specimens from the Coniacian brecciated limestones near Vera de Bidasoa (Northern Spain) are described. It is the first report of acanthochaetetids from Coniacian strata. The specimens are very small and probably lived in fissures and crevices in fore-reef breccias and deep water mud mounds. The family Acanthochaetetidae Fischer is placed in the order Hadromerida (Tetractinomorpha, Demospongiae). The order Tabulospongida Hartman & Goreau was abandoned.