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81.
Somatic translocation of antibody genes 总被引:36,自引:0,他引:36
82.
RNA-DNA hybrids at the cytological level 总被引:37,自引:0,他引:37
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Abnormal electroretinogram from a Drosophila mutant 总被引:21,自引:0,他引:21
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G. Deby-Dupont J. Pincemail A. Thirion C. Deby M. Lamy P. Franchimont 《Cellular and molecular life sciences : CMLS》1991,47(9):952-957
In order to obtain a radioimmunoassay (RIA) technique for the measurement of human plasma myeloperoxidase (MPO), we purified the enzyme from polymorphonuclear granulocytes (neutrophils), and compared three methods of labeling it with125Iodine: chloramine T, lactoperoxidase, and an original technique of self labeling based on the ability of the enzyme to oxidize and bind125I in the presence of H2O2. The chloramine T technique produced a degraded protein, as well shown by a high non-specific binding of tracer to antibody. The lactoperoxidase technique did not succeed in labeling MPO with an adequate specific activity. In contrast, the self-labeling method gave a stable tracer with a specific activity of 23 Ci/gmg MPO (85 MBq), a satisfactory level of immunoreactivity, and a low-specific binding (3%). After labeling, purification of tracer was achieved by gel filtration chromatography in phosphate buffer (0.05 M; pH7) to which 0.1% poly-L-lysine was added. The labeled molecule remained stable for 40 days and could be used for RIA with a polyclonal antibody raised in rabbits. 相似文献
89.
J. L. Lacuara S. R. de Barioglio P. P. de Oliva A. S. Bernacchi A. F. de Culasso J. A. Castro B. M. Franke de Cazzulo J. J. Cazzulo 《Cellular and molecular life sciences : CMLS》1991,47(6):612-616
Summary The tricyclic anti-calmodulin drug trifluoperazine (TFP) inhibited growth and motility of epimastigotes ofTrypanosoma cruzi, at concentrations lower than 100 M, and motility and infectivity of the bloodstream trypomastigote form at 200 M. Electron microscopy of TFP-treated epimastigotes showed that the major effect was at the mitochondrial level, with gross swelling and disorganization. The oligomycin-sensitive, mitochondrial ATPase was completely inhibited by 20 M TFP, and the same drug concentration caused a 60% decrease in intracellular ATP content. The results suggest that the trypanocidal effect of TFP may be related more to mitochondrial damage than to the well-known anticalmodulin effect of the drug. 相似文献
90.
A. Pletscher 《Cellular and molecular life sciences : CMLS》1991,47(1):4-8
Summary Modern treatment of mental depression started with the availability of monoamine oxidase (MAO) inhibitors and tricyclic antidepressants. These drugs also contributed to the early development of psychopharmacology. Attempts to improve the anti-tuberculous action of the hydrazine derivative isoniazid by developing derivatives thereof led to the synthesis of iproniazid. Its introduction as the first modern antidepressant was based on three unexpected actions of the drug: MAO-inhibition, reversal of reserpine-induced sedation, and the presence of psychostimulation as a clinical side effect in man. However, the initial success of iproniazid and other MAO inhibitors, hydrazides and non-hydrazides, was curtailed by the occurrence of undesirable side effects such as potentiation of the blood-pressure elevating action of food amines. The tricyclic antidepressants were a development of the class of antihistamines, one of which, chlorpromazine, showed neuroleptic activity. A congener of this compound, imipramine, was discovered by clinical observation to have unexpected antidepressant effects. The clinical success of this drug (which is still in use) led to the development of a successful series of other tricyclic and non-tricyclic antidepressants. Progress in the elucidation of possible mechanisms of the action of the tricyclic compounds has helped this development. Recent advances in basic research have also induced a revival of MAO-inhibitors since, due to the discovery of MAO-subtypes, inhibitors with higher specificity and fewer undesirable side effects are now available. 相似文献