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51.
Using a scintillation camera system, hemispheric and regional cerebral blood flow was measured repeatedly during the course after a stroke. In 20 patients who improved clinically mean hemispheric and regional flow and relative weight of rapidly perfused compartment increased, while these values decreased in 15 patients, on an average, whose clinical condition deteriorated or did not change. The changes of flow and relative weight were significantly different between the two groups. Futhermore, the relationship between changes in clinical condition, scored according to a rating scale, and changes in flow and compartmental weight was proved by significant Spearman rank correlation coefficients. In six cases hyperperfused areas in locations of disturbed neurological function were observed; these areas were found to be ischemic at measurements done early and late in the cours after the stroke. This type of hyperperfusion was related to beneficial prognosis. The results indicate a shift of tissue form fast to slowly cleared compartment after a cerebrovascular attack. If tissue morphology is not entirely destroyed, recovery might occur; this results in an increase of recorded weight of rapidly clearing compartments, which correlates to the clinical course. 相似文献
52.
1. The review summarizes the most important data known so far on chemistry, pharmacodynamics, toxicology and clinics of the investigational agent, pyridoindole stobadine. 2. Stobadine was shown to be able to scavenge hydroxyl, peroxyl and alkoxyl radicals, to quench singlet oxygen, to repair oxidized amino acids and to preserve oxidation of SH groups by one-electron donation. These effects originated from its ability to form a stable nitrogen-centered radical on indole nitrogen. Consequently, it was able to diminish lipid peroxidation and protein impairment under oxidative stress. 3. In various in vitro and in vivo animal models, stobadine was shown to diminish the impairment of the myocardium induced by mechanisms involving reactive oxygen species (e.g., myocardial infarction, hypoxia/ reoxygenation, catecholamine overexposure). 4. The neuroprotective effect of stobadine was demonstrated in a series of in vivo and in vitro models (brain in situ, brain slices, spinal cord, autonomic ganglia, etc.) during ischemia/reperfusion and hypoxia/ reoxygenation or in the presence of chemical systems generating free oxygen radicals, and so forth. Stobadine improved animal survival rate and synaptic transmission recovery, maintained SH tissue level and diminished lipid peroxidation as well as impairment of Ca-sequestering intracellular systems. 5. Oxidation of low-density lipoproteins (LDLs), which plays a major role in the development of atherosclerosis, was decreased by stobadine in vitro. Both lipid and protein (apo B) components of LDL were protected against Cu(2+)-induced oxidation by this agent. 6. Stobadine proved to be an effective protectant in models of free radical pathology in vivo, such as cyclophosphamide-, MNNG- or 60Co-induced mutagenesis and alloxan-induced hyperglycemia. 7. Besides other remarkable pharmacodynamic effects, stobadine exerts antidysrhythmic, local anesthetic, alpha-adrenolytic, antihistaminic, myorelaxant and antiulcerogenic actions. 8. Pharmacokinetic analyses demonstrated that stobadine was readily absorbed from the gastrointestinal tract. Thanks to its balanced lipo-hydrophilic properties, it was distributed over both water and lipid phases in biological tissues. It was shown to easily penetrate the blood-brain barrier. 9. Acute, subchronic and chronic toxicity studies in several animal species, as well as numerous analyses of embryotoxicity, teratogenicity, mutagenicity and genotoxicity, revealed only a negligible toxic potential of this agent. 10. Phase-one clinical study demonstrated safety of the compound. Only slight side effects--namely, a slight hypotension and a slight sedative effect--were observed subsequent to the highest dose used. In phase-two clinical study, the patients with angina pectoris treated for 4 weeks with stobadine showed a significant decrease in the frequency of anginal attacks, in the number of self-administrations of sublingual nitroglycerine and in plasma lipoprotein, cholesterol and triglyceride levels. A slight decrease in systolic and diastolic blood pressure also was observed. 11. It is suggested that stobadine may be considered a contribution to the search for new effective cardio- and neuroprotectants based on antioxidant or free radical scavenging mechanisms of action. 相似文献
53.
The synthesis of the murein precursor lipid I is performed by MraY. We have shown that mraY is an essential gene for cell growth. Cells depleted of MraY first swell and then lyse. The expression of mraY DNA in vitro produces a 40-kDa polypeptide detectable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 相似文献
54.
R Caplan S Arbelle W Magharious D Guthrie S Komo WD Shields S Chayasirisobhon R Hansen 《Canadian Metallurgical Quarterly》1998,40(12):805-811
Structured psychiatric interviews were administered to 60 children with complex partial seizure disorder (CPS), 40 children with primary generalized epilepsy with absences (PGE), and 48 control children, aged 5 to 16 years. Significantly more patients with epilepsy had psychiatric diagnoses compared with the control children. There were no statistically significant differences, however, in the number of patients with CPS and PGE with psychiatric diagnoses. Other than a schizophrenia-like psychosis found only in the patients with CPS, the two groups of patients had similar psychiatric diagnoses. The presence of psychopathology was related to significantly lower IQ scores and socioeconomic status, but not to seizure-related factors. These findings suggest that the psychopathology of children with CPS and PGE reflects different subtle neuropsychological deficits. 相似文献
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WD Fraser 《Canadian Metallurgical Quarterly》1997,57(5):212-214
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CT Powell NJ Brittis D Stec H Hug WD Heston WR Fair 《Canadian Metallurgical Quarterly》1996,7(4):419-428
Others have reported that the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA), an activator and down-regulator of most protein kinase C (PKC) isozymes, can induce apoptotic cell death of androgen-sensitive LNCaP but not androgen-insensitive PC-3 or DU 145 human prostate cancer cells. As a first step toward uncovering the mechanism by which TPA induces apoptosis of LNCaP cells, we quantified expression of PKC isozyme mRNAs in unmodified and TPA-resistant LNCaP cells and in naturally TPA-resistant PC-3, PC-3M, and DU 145 cells. All of the cell lines and normal prostate expressed RNAs for PKC alpha, delta, epsilon, eta, and mu; only DU 145 cells and normal prostate expressed PKC beta and theta RNAs, and none expressed PKC gamma. The amount of PKC alpha RNA and protein was 6- to 38-fold lower, and PKC mu RNA was 4.5- to 16.5-fold higher in unmodified and TPA-resistant LNCaP cells than in the androgen-independent cells. We examined the effects of TPA on PKC alpha and mu mRNA levels and on membrane translocation of PKC alpha. Incubation with TPA for 6 h or more induced 95% inhibition of cell growth, a transient 12-fold increase and 5-fold decrease in PKC alpha and mu mRNA levels, respectively, and prolonged translocation of PKC alpha to non-nuclear membranes in unmodified LNCaP cells and in TPA-resistant LNCaP cells from which TPA had been removed for 10 days. TPA-resistant LNCaP cells in the continuous presence of TPA, or 24 h after removal of TPA, had down-regulated PKC alpha and remained resistant to re-addition of TPA. These data demonstrate a strong correlation of the presence and absence of membrane PKC alpha with apoptosis and resistance to apoptosis, respectively. 相似文献