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Claudio O. Fernández Oscar Podestá Daniel A. Converso Marcelo E. Fernández A. J. Vila 《Journal of biological inorganic chemistry》1997,2(2):218-224
The heme protein wheat germ peroxidase (isoenzyme C2) and its cyanide-inhibited form have been investigated by means of electronic, CD and paramagnetic NMR spectroscopy. The
data indicate a protein environment of the active site distinct from that of horseradish peroxidase (HRP), with a larger solvent
accessibility. The iron is pentacoordinated at neutral and low pH, whereas a hydroxyl anion may be bound at alkaline pH. The
fifth axial ligand is a His residue with a partial anionic character, as found in other peroxidases. A spin equilibrium is
observed at high enzyme concentrations.
Received: 17 September 1996 / Accepted: 10 January 1997 相似文献
3.
Shayna A. Wrighten Gerardo G. Piroli Claudia A. Grillo Lawrence P. Reagan 《生物化学与生物物理学报:疾病的分子基础》2009,1792(5):444-453
Central nervous system (CNS) complications resulting from diabetes is a problem that is gaining more acceptance and attention. Recent evidence suggests morphological, electrophysiological and cognitive changes, often observed in the hippocampus, in diabetic individuals. Many of the CNS changes observed in diabetic patients and animal models of diabetes are reminiscent of the changes seen in normal aging. The central commonalities between diabetes-induced and age-related CNS changes have led to the theory of advanced brain aging in diabetic patients. This review summarizes the findings of the literature as they relate to the relationship between diabetes and dementia and discusses some of the potential contributors to diabetes-induced CNS impairments. 相似文献
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C Toga-Piquet A S Henderson J M Grillo A M Vagner-Capodano A Stahl 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1984,298(14):383-386
The Pig chromosomes that contain rDNA sites displayed a polymorphism in the distribution of the genes among the nucleolar organizers located on pairs Nos. 8 and 10. Two, or more often three, active sites were observed in the chromosomes of lymphocytes stimulated with phytohemagglutinin. Only 5% of the metaphases showed a 4th small active site. At the onset of stimulation most cells contained one-two nucleoli; four nucleoli were never observed. After prolonged stimulation, the number of nuclei containing three nucleoli increased. A 4th small nucleolus appeared in a few cells, presumably formed by activation of the smallest rDNA site. 相似文献
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L. Fontana C. Cravanzola S. Colombatto M. A. Grillo 《Cell biochemistry and function》1996,14(3):173-180
Uptake of polyamines has been investigated extensively in many cells, but not in placenta, where the polyamine– polyamine oxidase system is supposed to have an immunoregulatory function in pregnancy. Due to the importance of the transfer in this tissue, we have started this study. JAR human placental choriocarcinoma cells in monolayer at confluency were used as a model for measuring the key enzymes of polyamine synthesis and interconversion, rate of uptake and efflux, and the polyamine content. Polyamines were taken up by JAR cells and released by an independent mechanism. Ornithine decarboxylase and spermidine acetyltransferase activities and the rate of transport in and out of the cell were much higher than in other cells, such as L1210 cells. However the systems used for uptake and release appear in many respects to be similar to those observed in L1210 cells, but different from others. The uptake appears to be regulated by an inhibitory protein. Moreover, protein kinase C appears to be involved in the process. The efflux also is regulated as in L1210 cells, through control of H+ and Ca2+ concentration. In conclusion, this study shows that, in JAR cells, ornithine decarboxylase and spermidine acetyltransferase activities were much higher than in other cells, and so was the rate of transport in and out of the cells. As a result, a much higher polyamine content was observed. 相似文献
8.
Dalila Martínez de Muoz Rita Arenas Oscar Chvez Gonzlez 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,678(2)
A method for the simultaneous determination of HEPP (
-3-hydroxy-3-ethyl-3-phenylpropionamide), a member of a new homologous series of phenylamide-derivative anticonvulsants, with six other antiepileptic drugs (ethosuximide, primidone, phenobarbital, phenytoin, carbamazepine and clonazepam) in plasma by high-performance liquid chromatography is described. These drugs are extracted from plasma by adding an equal volume of acetonitrile. An aliquot of the extract is then injected on a reversed-phase column with a acetonitrile-methanol-phosphate buffer mobile phase. The total time required for the whole analytical process, including the plasma pretreatment and chromatography, is approximately 30 min. The assay method is simple, rapid and reproducible, and therefore considered suitable for routine use in clinical investigations monitoring HEPP simultaneously with common antiepileptic drugs. 相似文献
9.
Katherina Walz Devon Cohen Paul M. Neilsen Joseph Foster II. Francesco Brancati Korcan Demir Richard Fisher Michelle Moffat Nienke E. Verbeek Kathrine Bjørgo Adriana Lo Castro Paolo Curatolo Giuseppe Novelli Clemer Abad Cao Lei Lily Zhang Oscar Diaz-Horta Juan I. Young David F. Callen Mustafa Tekin 《Human genetics》2015,134(2):181-190
10.