Neuroprotection by ischemic preconditioning has been confirmed by many studies, but the precise mechanism remains unclear. In the present study, we performed cerebral ischemic pre- conditioning in rats by simulating a...Neuroprotection by ischemic preconditioning has been confirmed by many studies, but the precise mechanism remains unclear. In the present study, we performed cerebral ischemic pre- conditioning in rats by simulating a transient ischemic attack twice （each a 20-minute occlusion of the middle cerebral artery） before inducing focal cerebral infarction （2 hour occlusion-reper- fusion in the same artery）. We also explored the mechanism underlying the neuroprotective effect of ischemic preconditioning. Seven days after ocdusion-reperfusion, tetrazolium chloride staining and immunohistochemistry revealed that the infarct volume was significantly smaller in the group that underwent preconditioning than in the model group. Furthermore, vascular endothelial growth factor immunoreactivity was considerably greater in the hippocampal CA3 region of preconditioned rats than model rats. Our results suggest that the protective effects of ischemic preconditioning on focal cerebral infarction are associated with upregulation of vascu- lar endothelial growth factor.展开更多
BACKGROUND： Studies have demonstrated that the risk factors of vascular dementia following stroke are greatly different in region, race and other aspects. OBJECTIVE： To analyze the conditions and incidental risk fac...BACKGROUND： Studies have demonstrated that the risk factors of vascular dementia following stroke are greatly different in region, race and other aspects. OBJECTIVE： To analyze the conditions and incidental risk factors of vascular dementia in patients with acute cerebral infarction from Chongqing City. DESIGN： Case analysis. SETTING： Department of Neurology, Daping Hospital, Third Military Medical University of Chinese PLA. PARTICIPANTS： Altogether 546 inpatients with acute ischemic stroke admitted to Department of Neurology, Daping Hospital, Third Military Medical University of Chinese PLA between May 1999 and December 2002 were involved in this study. The involved patients, including 295 males and 251 females, aged 55 - 94 years, dwelled in Chongqing over 5 years. They were admitted to hospital within 48 hours of attack of acute ischemic stroke, and survived for over 3 months. Informed consents were obtained from all the involved subjects. METHODS： ① Following the same standard, cognitive and social function evaluations were conducted by one physician on admission and 3 months after admission, Unified questionnaire, consisting of general characteristics, vascular risk factors, stroke characteristics, neurological physical sign, and other 28 factors of involved subjects, was used in all the patients. According to the investigation results, the patients were assigned into 2 groups： dementia group and non-dementia group. ②Ischemic stroke was diagnosed according to acute ischemic brain disorder 〉 24 hours and CT or MRI imageology.③ Neurophysiological examination was conducted in all the patients at 7 to l0 days after stroke （score was two SD less than or equaled to normal level was considered as abnormal）. ④Diagnosis and statistics of dementia were carried out with Mini-Mental State Examination and The Diagnostic and Statistical Manual of Mental Disorders-Ⅳ （published by American Psychiatric Association） on admission and 3 months after admission. Neurologic deficit scoring was carried out with the National Institutes of Health Stroke Scale. ⑤ Chi-square test was used for categorical variable, and t test for quantitative variable between dementia group and non-dementia group. Dementia-related factors were performed multiple-factor Logistic regression model analysis. MAIN OUTCOME MEASURES： Incidence of dementia and dementia-related risk factors of patients. RESULTS： Altogether 546 patients with stroke were involved in this study, 403 of them participated in the final analysis, and 143 dropped out. A total of 342 were followed-up in the hospital and 61 at home. At 3 months after cerebral infarction, vascular dementia occurred in 87 （21.6%） of 403 patients. The main risk factors were age （OR 1.179; 95%CI 1.130 - 1.230）, low education level （OR 1.806; 95%CI 1.024 - 3.186）, daily alcohol drinking （OR 3.447; 95%（1/ 1.591 - 7.468）, stroke history （OR 2.531; 95%CI 1.419 - 4.512）, atrial fibrilation（OR 3.475; 95%CI 1.712 - 7.057）, dysphonia （OR 5.873; 95%6/2.620 - 13.163） and left carotid artery infarction （OR 1.975; 95%（1/1.152 - 3.388）. CONCLUSION： The incidence of vascular dementia is determined by synthetic action of multiple risk factors. Dysphonia is the most important influencing factor.展开更多
Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute cerebral infarction, but the mechanisms underlying this protection remain unclear. To investigate the protective mechanisms ...Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute cerebral infarction, but the mechanisms underlying this protection remain unclear. To investigate the protective mechanisms of hypoxic preconditioning in relation to its effects on angiogenesis, we in- duced a photochemical model of cerebral infarction in an inbred line of mice （BALB/c）. Mice were then exposed to hypoxic preconditioning 30 minutes prior to model establishment. Results showed significantly increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra at 24 and 72 hours post infarction, mainly in neurons and vascular endothelial cells. Hypoxic preconditioning increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra and the expression of vascular endothelial growth factor was positively related to that of CD31. Moreover, hypoxic preconditioning reduced the infarct volume and improved neu- rological function in mice. These findings indicate that the protective role of hypoxic preconditioning in acute cerebral infarction may possibly be due to an increase in expression of vascular endothelial growth factor and CD31 in the ischemic penumbra, which promoted angiogenesis.展开更多
In this study, we hypothesized that an increase in integrin αβand its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning wi...In this study, we hypothesized that an increase in integrin αβand its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning with bilateral common carotid artery occlusion for 5 minutes in C57BL/6J mice. This was followed by ischemic injury with bilateral common carotid artery occlusion for 30 minutes. The time interval between ischemic preconditioning and lethal ischemia was 48 hours. Histopathological analysis showed that ischemic preconditioning substantially diminished damage to neurons in the hippocampus 7 days after ischemia. Evans Blue dye assay showed that ischemic preconditioning reduced damage to the blood-brain barrier 24 hours after ischemia. This demonstrates the neuroprotective effect of ischemic preconditioning. Western blot assay revealed a significant reduction in protein levels of integrin αβ, vascular endothelial growth factor and its receptor in mice given ischemic preconditioning compared with mice not given ischemic preconditioning 24 hours after ischemia. These findings suggest that the neuroprotective effect of ischemic preconditioning is associated with lower integrin αβand vascular endothelial growth factor levels in the brain following ischemia.展开更多
目的探讨急性心肌梗死患者在常规治疗的基础上加用新活素对血管内皮功能的影响。方法选择急性心肌梗死患者60例,随机分为实验组30例及对照组30例。对照组患者给予常规药物治疗,实验组患者在常规治疗基础上即刻静脉注射新活素。治疗前及...目的探讨急性心肌梗死患者在常规治疗的基础上加用新活素对血管内皮功能的影响。方法选择急性心肌梗死患者60例,随机分为实验组30例及对照组30例。对照组患者给予常规药物治疗,实验组患者在常规治疗基础上即刻静脉注射新活素。治疗前及治疗后2周超声观察肱动脉内皮依赖性舒张功能(FMD)的变化。2组分别在治疗前及治疗后2周采集静脉血,所有标本收集后统一检测。ELISA测定2组患者治疗前及治疗后血清NO及内皮素1含量。结果实验组治疗后FMD较对照组明显升高(15.09±1.13 vs 9.14±2.82,P<0.05);实验组治疗后血清NO含量较治疗前明显升高[(45.09±5.65)μmol/L vs(37.67±5.43)μmol/L,P<0.05],内皮素1含量较治疗前明显降低[(72.08±20.94)ng/L vs(84.56±23.83)ng/L,P<0.05];实验组治疗后血清NO含量较对照组明显升高,内皮素1含量较对照组明显降低。结论新活素能够通过增加血液中NO含量,降低内皮素1含量,改善急性心肌梗死患者的血管内皮功能,是其治疗急性心肌梗死的机制之一。展开更多
文摘Neuroprotection by ischemic preconditioning has been confirmed by many studies, but the precise mechanism remains unclear. In the present study, we performed cerebral ischemic pre- conditioning in rats by simulating a transient ischemic attack twice （each a 20-minute occlusion of the middle cerebral artery） before inducing focal cerebral infarction （2 hour occlusion-reper- fusion in the same artery）. We also explored the mechanism underlying the neuroprotective effect of ischemic preconditioning. Seven days after ocdusion-reperfusion, tetrazolium chloride staining and immunohistochemistry revealed that the infarct volume was significantly smaller in the group that underwent preconditioning than in the model group. Furthermore, vascular endothelial growth factor immunoreactivity was considerably greater in the hippocampal CA3 region of preconditioned rats than model rats. Our results suggest that the protective effects of ischemic preconditioning on focal cerebral infarction are associated with upregulation of vascu- lar endothelial growth factor.
文摘BACKGROUND： Studies have demonstrated that the risk factors of vascular dementia following stroke are greatly different in region, race and other aspects. OBJECTIVE： To analyze the conditions and incidental risk factors of vascular dementia in patients with acute cerebral infarction from Chongqing City. DESIGN： Case analysis. SETTING： Department of Neurology, Daping Hospital, Third Military Medical University of Chinese PLA. PARTICIPANTS： Altogether 546 inpatients with acute ischemic stroke admitted to Department of Neurology, Daping Hospital, Third Military Medical University of Chinese PLA between May 1999 and December 2002 were involved in this study. The involved patients, including 295 males and 251 females, aged 55 - 94 years, dwelled in Chongqing over 5 years. They were admitted to hospital within 48 hours of attack of acute ischemic stroke, and survived for over 3 months. Informed consents were obtained from all the involved subjects. METHODS： ① Following the same standard, cognitive and social function evaluations were conducted by one physician on admission and 3 months after admission, Unified questionnaire, consisting of general characteristics, vascular risk factors, stroke characteristics, neurological physical sign, and other 28 factors of involved subjects, was used in all the patients. According to the investigation results, the patients were assigned into 2 groups： dementia group and non-dementia group. ②Ischemic stroke was diagnosed according to acute ischemic brain disorder 〉 24 hours and CT or MRI imageology.③ Neurophysiological examination was conducted in all the patients at 7 to l0 days after stroke （score was two SD less than or equaled to normal level was considered as abnormal）. ④Diagnosis and statistics of dementia were carried out with Mini-Mental State Examination and The Diagnostic and Statistical Manual of Mental Disorders-Ⅳ （published by American Psychiatric Association） on admission and 3 months after admission. Neurologic deficit scoring was carried out with the National Institutes of Health Stroke Scale. ⑤ Chi-square test was used for categorical variable, and t test for quantitative variable between dementia group and non-dementia group. Dementia-related factors were performed multiple-factor Logistic regression model analysis. MAIN OUTCOME MEASURES： Incidence of dementia and dementia-related risk factors of patients. RESULTS： Altogether 546 patients with stroke were involved in this study, 403 of them participated in the final analysis, and 143 dropped out. A total of 342 were followed-up in the hospital and 61 at home. At 3 months after cerebral infarction, vascular dementia occurred in 87 （21.6%） of 403 patients. The main risk factors were age （OR 1.179; 95%CI 1.130 - 1.230）, low education level （OR 1.806; 95%CI 1.024 - 3.186）, daily alcohol drinking （OR 3.447; 95%（1/ 1.591 - 7.468）, stroke history （OR 2.531; 95%CI 1.419 - 4.512）, atrial fibrilation（OR 3.475; 95%CI 1.712 - 7.057）, dysphonia （OR 5.873; 95%6/2.620 - 13.163） and left carotid artery infarction （OR 1.975; 95%（1/1.152 - 3.388）. CONCLUSION： The incidence of vascular dementia is determined by synthetic action of multiple risk factors. Dysphonia is the most important influencing factor.
基金supported by the National Natural Science Foundation of China,No.30870854the Natural Science Foundation of Beijing,No.7111003the Natural Science Foundation of Shandong Province,No.ZR2010HM029
文摘Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute cerebral infarction, but the mechanisms underlying this protection remain unclear. To investigate the protective mechanisms of hypoxic preconditioning in relation to its effects on angiogenesis, we in- duced a photochemical model of cerebral infarction in an inbred line of mice （BALB/c）. Mice were then exposed to hypoxic preconditioning 30 minutes prior to model establishment. Results showed significantly increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra at 24 and 72 hours post infarction, mainly in neurons and vascular endothelial cells. Hypoxic preconditioning increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra and the expression of vascular endothelial growth factor was positively related to that of CD31. Moreover, hypoxic preconditioning reduced the infarct volume and improved neu- rological function in mice. These findings indicate that the protective role of hypoxic preconditioning in acute cerebral infarction may possibly be due to an increase in expression of vascular endothelial growth factor and CD31 in the ischemic penumbra, which promoted angiogenesis.
基金supported by grants from the National Natural Science Foundation of China,No.81071068the Israel Science Foundation-the National Natural Science Foundation of China(Joint Program),No.813111290the Natural Science Foundation of Guangdong Province in China,No.2014A030313172
文摘In this study, we hypothesized that an increase in integrin αβand its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning with bilateral common carotid artery occlusion for 5 minutes in C57BL/6J mice. This was followed by ischemic injury with bilateral common carotid artery occlusion for 30 minutes. The time interval between ischemic preconditioning and lethal ischemia was 48 hours. Histopathological analysis showed that ischemic preconditioning substantially diminished damage to neurons in the hippocampus 7 days after ischemia. Evans Blue dye assay showed that ischemic preconditioning reduced damage to the blood-brain barrier 24 hours after ischemia. This demonstrates the neuroprotective effect of ischemic preconditioning. Western blot assay revealed a significant reduction in protein levels of integrin αβ, vascular endothelial growth factor and its receptor in mice given ischemic preconditioning compared with mice not given ischemic preconditioning 24 hours after ischemia. These findings suggest that the neuroprotective effect of ischemic preconditioning is associated with lower integrin αβand vascular endothelial growth factor levels in the brain following ischemia.
文摘目的探讨急性心肌梗死患者在常规治疗的基础上加用新活素对血管内皮功能的影响。方法选择急性心肌梗死患者60例,随机分为实验组30例及对照组30例。对照组患者给予常规药物治疗,实验组患者在常规治疗基础上即刻静脉注射新活素。治疗前及治疗后2周超声观察肱动脉内皮依赖性舒张功能(FMD)的变化。2组分别在治疗前及治疗后2周采集静脉血,所有标本收集后统一检测。ELISA测定2组患者治疗前及治疗后血清NO及内皮素1含量。结果实验组治疗后FMD较对照组明显升高(15.09±1.13 vs 9.14±2.82,P<0.05);实验组治疗后血清NO含量较治疗前明显升高[(45.09±5.65)μmol/L vs(37.67±5.43)μmol/L,P<0.05],内皮素1含量较治疗前明显降低[(72.08±20.94)ng/L vs(84.56±23.83)ng/L,P<0.05];实验组治疗后血清NO含量较对照组明显升高,内皮素1含量较对照组明显降低。结论新活素能够通过增加血液中NO含量,降低内皮素1含量,改善急性心肌梗死患者的血管内皮功能,是其治疗急性心肌梗死的机制之一。
