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131.
Iliana Ferrero C. Rossi N. Marmiroli Claudia Donnini P. P. Puglisi 《Antonie van Leeuwenhoek》1981,47(4):311-323
Mitochondrial protein synthesis, primary (antimycin-sensitive) respiration and secondary (antimycin-insensitive, salicyl-hydroxamate-sensitive)
respiration, have been characterized in the dimorphic yeastEndomycopsis capsularis.
The inhibition by chloramphenicol (CAP) of the morphogenetic development from the yeast-like form to the mycelial structure
in this yeast could represent the intervention in the morphogenetic process of mitochondrial protein synthesis, since chloramphenicol
blocks in vivo and in vitro mitochondrial protein synthesis. In fact, other functions such as primary and secondary respiration,
do not seem to play a role in the morphogenetic development since their inhibition by antimycin A (AA) or by salicyl-hydroxamic
acid (SHAM) does not affect the process. In addition, mitochondrial protein synthesis has been shown to be uninhibited by
the two respiratory inhibitors. 相似文献
132.
R Misiani A C Appiani A Edefonti E Gotti A Bettinelli M Giani E Rossi G Remuzzi G Mecca 《BMJ (Clinical research ed.)》1982,285(6351):1304-1306
The therapeutic effect of plasma infusion was evaluated in 10 children and seven adults with haemolytic uraemic syndrome. All but one patient responded to this treatment with rapid disappearance of haematological abnormalities. The patient who apparently failed to respond to plasma infusion obtained complete remission of the disease after plasmapheresis. Although 15 of the 17 patients were anuric or oliguric on admission, renal function recovered completely in eight children and two adults. Seven patients showed residual chronic renal failure and two required long-term maintenance haemodialysis. Treatment with plasma was also successful in patients with relapses or recurrent episodes. Plasma infusion is a promising therapeutic approach for the haemolytic uraemic syndrome and deserves further study in clinical trials. 相似文献
133.
Giacomino Randazzo Antonio Evidente Alberto Boccalatte Carlo Rossi 《Phytochemistry》1981,20(9):2177-2181
Measurement of isotope ratios in 1α,2α,3β-trihydroxy-p-menthane, which has been biosynthesized in Fusicoccum amygdali from 3H- and 14C-labelled mevalonate and in its degradation product diosphenol indicates that: (a) four tritium atoms arising from [5-3H2, 2-14C]MVA are retained, one more than suggested from the hydroxylation pattern, (b) menth-2-ene-1-ol is generated from an α-terpinyl cation through a 1,3-hydride shift and (c) trans-cleavage of an α-epoxide by hydrolysis gives 1α,2α,3β-trihydroxy-p-menthane. 相似文献
134.
Stimulation of the calmodulin-independent activity of the red cell Ca2+-pump ATPase by trypsin treatment (of calmodulin free red cell membranes) is sensitive to Ca2+ in a concentration range near the KCa of the transport site. The Ca2+ requirement for this effect is absolute, whereas the calmodulin sensitivity of the ATPase can be abolished by sufficient trypsin attack in the absence of Ca2+, although Ca2+ accelerates inactivation. This indicates that the two effects of trypsin are due to at least two distinct cleavage sites in the pump protein. 相似文献
135.
J Olivares A Ray J Aussedat M Verdys A Rossi 《Biochemical and biophysical research communications》1980,95(1):367-373
In a first phase (up to 12h) after the first injection of isoproterenol (5mg.kg?1 b.w.) the pyrimidine nucleotide pools were increased and the rates of incorporation of inorganic phosphate into the α-phosphate groups of nucleotides were raised from 16 to 58 nmol.g?1.h?1 for uracil nucleotides and from 11 to 32 nmol.g?1.h?1 for cytosine nucleotides. At a later stage, while the pool sizes decreased slowly toward control levels, these rates of labelling also decreased though still remaining above control values. A similar pattern of changes was induced by the eighth daily isoproterenol injection, but the alterations were attenuated. 相似文献
136.
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139.
DRI Pietro Bellavite Paolo Berton Giorgio Rossi Filippo 《Molecular and cellular biochemistry》1979,23(2):109-122
The paper presents an experimental procedure for a simultaneous assay of oxygen consumption, O2- release and H2O2 accumulation at a very early stage of the respiratory burst that is induced by phagocytosis in guinea pig polymorphonuclear leucocytes. The main findings are as follows: (a) The oxygen consumption that is measurable does not correspond to all oxygen that is reduced. The relationship between the actual oxygen consumed and the amount that is reduced depends on the fate of the intermediate products O2- and H2O2. (b) O2- is measurable extracellularly by the reduction of cytochrome c. When cytochrome c oxidizes the extracellular O2-, molecular oxygen is formed. This fact is shown by a decrease of oxygen consumption. The molar ratio between the O2- detected and the oxygen given back is 1. (c) The amount of O2- released from the cells accounts for only a small part of oxygen actually reduced. (d) H2O2 is detectable only in the presence of NaN3. In this condition almost all oxygen consumed is recovered in the form of H2O2. The molar ratio O2/H2O2 is near unity. The amount of H2O2 derived from dismutation of O2- released is only an aliquot of the total H2O2 accumulated. Thus, most of H2O2 is derived from intracellular sources. (e) In the absence of inhibitors of H2O2 degrading reactions, no detectable accumulation of peroxide occurs. Under these conditions, the main part of H2O2 formed is degraded in almost equal amount by catalase and myeloperoxidase, while only a small aliquot is degraded by NaN3 insensitive reactions. 相似文献
140.
This paper reports the properties of human hemoglobin covalently bound to Sepharose 4B both in 'high-affinity' and 'low-affinity' conformations. The results suggest that the coupling reaction is strongly affected by the conformational changes linked to oxygenation of the protein. The rate and the extent of the reaction are different for the oxy and deoxyderivatives, probably due to the change in reactivity of the amino groups in the liganded and unliganded tetramer. The data on the equilibrium which is established between matrix-bound and soluble subunits, measured by the 'subunit-exchange chromatography', indicate that the system displays a minimal heterogeneity when hemoglobin is coupled to the gel in the deoxy state at intermediate protein concentration and pH 8. Maxtrix-bound hemoglobin is characterized by a higher oxygen affinity and by decreased homotropic and heterotropic interactions with respect to hemoglobin in solution, but the changes depend strongly on the conditions used in the coupling procedure. 相似文献