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In brain regions containing noradrenergic (NA) cell bodies or terminals, DSP-4 induces changes in the activity of catecholamine-synthesizing enzymes which suggest that central NA neurons are lesioned by this neurotoxin. In contrast, the lack of change in the same enzymatic activities in an area containing mostly adrenergic (A) neurons (C2 region), favors the hypothesis of a resistance of the A neurons to DSP-4. Furthermore, the enzymatic changes observed in peripheral organs suggest a peripheral activation of the NA cell bodies in response to lesioning of the sympathetic terminals by DSP-4.  相似文献   
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OBJECTIVE: Cell therapy may be a promising alternative or adjunct to current treatment modalities for ischemic heart failure. But little is known on the impact of myogenic cell transplantation in large animal models of non-ischemic cardiomyopathy. The aim of the present study was to explore whether an ovine model of toxin-induced heart disease could benefit from non-cultured skeletal muscle cell transplantation. METHODS: Sequential intracoronary injections of doxorubicin (0.75 mg/kg) were carried out every 2 weeks until echocardiographic detection of myocardial dysfunction. Sheep were then randomly assigned to either non-cultured cell transplantation (n=8) or placebo injection (n=5). For the cell therapy group, a skeletal muscle biopsy (about 10 g) was explanted from each animal approximately 3h before grafting. After thoracotomy, 20 epicardial injections were carried out. The animals were assessed one last time before sacrifice, 2 months after the thoracotomy. Cells were tracked with cmDiI (red fluorescence) and characterized with immunohistochemistry with monoclonal antibodies to a fast skeletal isoform of myosin heavy chain. RESULTS: Two months after intramyocardial grafting, tissue Doppler imaging and conventional echocardiographic assessment of the groups showed a marked improvement in the non-cultured cell therapy group. Ejection fraction (EF) (p<0.05) as well as systolic endocardial velocities (p<0.01) improved versus the placebo group. CmDiI and skeletal myosin heavy chain expression was detected in all animals at 2 months after implantation confirming engraftment of skeletal muscle cells. CONCLUSIONS: In conclusion, our data indicate that non-cultured muscle cell transplantation is feasible and may translate into a functional benefit in an ovine model of dilated heart failure.  相似文献   
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Molsidomine and its metabolite, SIN-1, a donor of nitric oxide, are potent coronary vasodilator and anti-ischemic agents. Recently, SIN-1 and nitric oxide have also been shown to inhibit platelet adhesion and aggregation in vitro. The present study in dogs was designed to evaluate the in vivo antithrombotic properties of SIN-1. Coronary intimal damage and stenosis are known to induce coronary cyclic flow variations that reflect platelet thrombus formation followed by disaggregation and embolization (Folts preparation). This model of coronary artery thrombosis appears to simulate the combination of some of the factors contributing to unstable angina and myocardial infarction in human. SIN-1 infusion (10 micrograms/kg/min) significantly reduced the frequency of cyclic flow variations: 4.9 +/- 6.2/h vs. 14 +/- 4.6/h (before treatment, p less than 0.03, n = 6). Results were similar to those obtained with aspirin (5 mg/kg, bolus i.v.: 1.5 +/- 0.6/h vs. 11.7 +/- 3/h, p less than 0.03, n = 5) whereas saline had no effect (17.8 +/- 2.2/h vs. 19.3 +/- 2.4/h, n = 5). As expected, blood pressure was decreased only in the SIN-1 group: 56.2 +/- 7.8 vs. 87.3 +/- 9.3 mm Hg (p less than 0.02) (mean arterial blood pressure). The present results suggest that the well-documented anti-ischemic properties of SIN-1 could be partly due to its antithrombotic activity, clearly demonstrated with the model of coronary thrombosis used here in the dog.  相似文献   
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The Onchocerciasis Control Program of the World Health Organization is carrying out an extensive screening program in a search for new larvicides to be used for control of Simulium damnosum s.l. Emphasis has been given to finding a pyrethroid and a carbamate to supplement the organophosphates currently in use. These chemicals with differing modes of action, together with Bacillus thuringiensis H-14, are being used in an attempt to cope with the development and spread of resistance to the organophosphates temephos and chlorphoxim.  相似文献   
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The severity of pulmonary embolism (PE) ranges from asymptomaticto cardiogenic shock with corresponding short-term mortalitybetween 2 and 95%. Whereas the former could be discharged earlyor managed entirely as outpatients using low-molecular-weightheparin, those with greater severity of PE require rapid echocardiographyto evaluate for indications for immediate thrombolysis or embolectomy.2,3However, most patients with PE fall between these two extremes.Patients with PE who do not initially present with life-threateningcriteria are usually admitted to a hospital ward where thosewith intermediate risk might experience a life-threatening recurrentepisode requiring emergent thrombolysis and critical care. Therefore,among patients with intermediate clinical severity, it is criticalto accurately identify those at risk for adverse medical outcome. Despite recent advances in risk stratification,  相似文献   
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