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Background
The intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator (rt-PA) therapy is safe and efficient during the treatment of acute ischemic stroke. Nonetheless, the different outcomes among various stroke subgroups have limited data with regard to the safety and efficacy of cryptogenic stroke (CS). The present study compared the safety and efficacy when IVT with rt-PA was used for the treatment of CS and the other stroke subtypes.Methods
This study classified the IVT with rt-PA patients within 4.5 hours after stroke onset, based on the trial of ORG 10172 in acute stroke treatment criteria in terms of diagnostic evaluation. The data were obtained from the Thrombolysis Implementation and Monitor of Acute Ischemic Stroke in China database, a large multicenter prospective registry. A multivariable logistic regression model was employed to compare the differences between the subtypes in symptomatic intracerebral hemorrhage (sICH) within 7 days and studied the mortality and the outcome during 90 days.Results
In total, 1118 patients were recruited; of these, 131 (11.7%) suffered from CS and 987 (88.3%) with the other etiology. In the CS group, patients were younger than those in the other etiology groups (P < .001). Moreover, it had a lower prevalence of previous stroke (P?=?.0117), receiving antiplatelet drug in 24 hours prior to thrombolysis (P?=?.0017), and functional independence (mRS > 1 before stroke, P?=?.003). The CS group had lower blood pressure (systolic blood pressure P?=?.0001; diastolic blood pressure; P?=?.0212) before thrombolysis, atrial fibrillation (P < .001), and diabetes mellitus (P?=?.0005). Transient ischemic attack, hypertension, hyperlipidemia, blood glucose, receiving anticoagulants in 24 hours prior to thrombolysis, and standard dosage of rt-PA were equally distributed in both groups. After the adjustment of confounders between the CS and the other subgroups, no obvious differences were observed in sICH rate and mortality (P > .05) The CS patients exhibited excellent recovery (mRS, 0-1; 63.78%) and functional independence (mRS, 0-2; 74.8%) than the large artery atherosclerosis patients.Conclusions
IVT with rt-PA is a safe and effective method for the treatment of CS patients. 相似文献It is well-known that in ischemia-induced hypoxia, hypoxia-inducible factor -1α (HIF-1α) is critical in triggering expression of its downstream target genes to produce several products, such as erythropoietin (EPO), vascular endothelial growth factor (VEGF), nitric oxide synthesis (NOS), glucose transportor-1 (GLUT-1), insulin-like growth factor (IGF), which further promote erythropoiesis, angiogenesis, vasodilation and capitalization of glucose to overcome hypoxia. Meanwhile, as the factors with opposite effects on blood vessels, endothelin-1 (ET-1) and brain natriuretic peptide (BNP) also stand out strikingly in ischemic pathophysiology. To this day, several preconditioning manners have been used to induce tolerance to ischemia. During our research, exercise preconditioning was applied and it was demonstrated that HIF-1α triggered expression of ET-1 and BNP, which confirmed their downstream target genes for HIF-1α. And ET-1 may influcence expression of BNP to some degree but not the only factor which regulates BNP expression. Therefore, our findings suggest exercise preconditioning may provide protection to the ischemic brain tissue via HIF-1α which in turn increases expression of BNP to cause vasodilation in cooperation with some other factors, such as VEGF and EPO, to increase the blood flow in the ischemic area and then relieve the injuries induced by ischemia.
相似文献Methods: In this study, Wnt4 gene overexpression and knockdown were performed in PINK1 mutant PD transgenic Drosophila, and the protective effect of Wnt4 gene on PD transgenic Drosophila and its possible mechanism were explored. The Wnt4 gene was screened in the previous experiment; And by using the PD transgenic Drosophila model of the MHC-Gal4/UAS system, the PINK1 gene could be specifically activated in the Drosophila muscle tissue.
Results: In PINK1 mutation transgenic fruit flies, the Wnt4 gene to study its implication on PD transgenic fruit flies’ wing normality and flight ability. We found that overexpression of Wnt4 gene significantly reduced abnormality rate of PD transgenic Drosophila and improved its flight ability, and then, increased ATP concentration, enhanced mitochondrial membrane potential and normalized mitochondrial morphology were found. All of these findings suggested Wnt4 gene may have a protective effect on PD transgenic fruit flies. Furthermore, in Wnt4 gene overexpression PD transgenic Drosophila, down-regulation autophagy and apoptosis-related proteins Ref(2)P, Pro-Caspase3, and up-regulation of Beclin1, Atg8a, Bcl2 protein were confirmed by Western Blotting.
Conclusion: The results imply that the restoring of mitochondrial function though Wnt4 gene overexpression in the PINK1 mutant transgenic Drosophila may be related to autophagy and/or apoptosis. 相似文献