Context: Recent studies suggest that factors other than the degree of carotid stenosis are involved in ischemic stroke pathogenesis, especially modifications of plaque composition and related complications. Abstract:O...Context: Recent studies suggest that factors other than the degree of carotid stenosis are involved in ischemic stroke pathogenesis, especially modifications of plaque composition and related complications. Abstract:Objective: To examine the role of carotid plaque rupture and thrombosis in ischemic stroke pathogenesis in patients undergoing carotid endarterectomy, excluding those with possible cardiac embolization or with severe stenosis of the circle of Willis. Design, Setting, and Patients: A total of 269 carotid plaques selected from an Interinstitutional Carotid Tissue Bank were studied by histology after surgical endarterectomy between January 1995 and December 2002. A total of 96 plaques were from patients with ipsilateral major stroke, 91 plaques from patients with transient ischemic attack (TIA), and 82 plaques from patients without symptoms. Main Outcome Measures: Differences in the frequency of thrombosis, cap rupture, cap erosion, inflammatory infiltrate, and major cardiovascular risk factors between study groups. Results: A thrombotically active carotid plaque associated with high inflammatory infiltrate was observed in 71 (74.0% ) of 96 patients with ipsilateral major stroke (and in all 32 plaques from patients operated within 2 months of symptom onset) compared with 32 (35.2% ) of 91 patients with TIA (P < .001) or 12 (14.6% ) of 82 patients who were without symptoms (P < .001). In addition, a fresh thrombus was observed in 53.8% of patients with stroke operated 13 to 24 months after the cerebrovascular event. An acute thrombus was associated with cap rupture in 64 (90.1% ) of 71 thrombosed plaques from patients with stroke and with cap erosion in the remaining 7 cases (9.9% ). Ruptured plaques of patients affected by stroke were characterized by the presence of a more severe inflammatory infiltrate, constituted by monocytes, macrophages, and T lymphocyte cells compared with that observed in the TIA and asymptomatic groups (P=.001). There was no significant difference between groups in major cardiovascular risk factors. Conclusion: These results demonstrate a major role of carotid thrombosis and inflammation in ischemic stroke in patients affected by carotid atherosclerotic disease.展开更多
OBJECTIVE: To study whether recombinant adeno-associated virus (rAAV) mediated foreign gene, LacZ, could pass the blood brain barrier by intra-carotid artery delivery and express in vivo in ischemic brain of the foc...OBJECTIVE: To study whether recombinant adeno-associated virus (rAAV) mediated foreign gene, LacZ, could pass the blood brain barrier by intra-carotid artery delivery and express in vivo in ischemic brain of the focal embolic stroke rats to investigate a possibility of delivering foreign gene through carotid artery to treat acute ischemic stroke. METHODS: The carotid artery territory in 41 rats was embolized with or without arterial-like fibrin rich clots to make a model of focal embolic stroke rat. rAAV containing LacZ gene (rAAV-LacZ) was constructed in 293 cells by calcium phosphate cotransfection. The rats were assigned to one of the following treatments: 1 control (without embolism) groups, including PBS treated (n = 6), pLacZ treated (n = 6 ) and rAAV-LacZ treated (n = 6): 2 embolic groups, including embolism + PBS (n =7),embolism + pLacZ (n = 8) and embolism + rAAV-LacZ (n = 8). Brains were cryosectioned and kappa-Gal stain was performed at 2, 4, and 8 weeks, respectively, after transfection, and then infarct volume was measured and the percentage of LacZ staining-positive cells was calculated. RESULTS: In all the control groups and embolism + PBS treated animal, no kappa-Gal staining-positive cells were found, but in embolism + pLacZ (n = 8) and embolism+rAAV-LacZ groups a lot of kappa-Gal staining-positive cells were found. The expression cells were in the tissues around the infarction. The gene expression persisted only nearly four weeks in embolic group with pLacZ. In the embolic group with rAAV-LacZ the expression was very stable during the experiment course (eight weeks) and the percentage of the expressed cells was significantly higher than that of its contralateral areas at the same time points, respectively. CONCLUSIONS: The plasmid vector and rAAV could enter the brain through the ischemia-damaged blood barrier and foreign gene can be expressed in brain. The positive gene expression is mainly in the peripheral areas of the infarction. rAAV as a permanent expression vector may ultimately be used for gene therapy of human ischemia cerebravascular diseases.展开更多
文摘Context: Recent studies suggest that factors other than the degree of carotid stenosis are involved in ischemic stroke pathogenesis, especially modifications of plaque composition and related complications. Abstract:Objective: To examine the role of carotid plaque rupture and thrombosis in ischemic stroke pathogenesis in patients undergoing carotid endarterectomy, excluding those with possible cardiac embolization or with severe stenosis of the circle of Willis. Design, Setting, and Patients: A total of 269 carotid plaques selected from an Interinstitutional Carotid Tissue Bank were studied by histology after surgical endarterectomy between January 1995 and December 2002. A total of 96 plaques were from patients with ipsilateral major stroke, 91 plaques from patients with transient ischemic attack (TIA), and 82 plaques from patients without symptoms. Main Outcome Measures: Differences in the frequency of thrombosis, cap rupture, cap erosion, inflammatory infiltrate, and major cardiovascular risk factors between study groups. Results: A thrombotically active carotid plaque associated with high inflammatory infiltrate was observed in 71 (74.0% ) of 96 patients with ipsilateral major stroke (and in all 32 plaques from patients operated within 2 months of symptom onset) compared with 32 (35.2% ) of 91 patients with TIA (P < .001) or 12 (14.6% ) of 82 patients who were without symptoms (P < .001). In addition, a fresh thrombus was observed in 53.8% of patients with stroke operated 13 to 24 months after the cerebrovascular event. An acute thrombus was associated with cap rupture in 64 (90.1% ) of 71 thrombosed plaques from patients with stroke and with cap erosion in the remaining 7 cases (9.9% ). Ruptured plaques of patients affected by stroke were characterized by the presence of a more severe inflammatory infiltrate, constituted by monocytes, macrophages, and T lymphocyte cells compared with that observed in the TIA and asymptomatic groups (P=.001). There was no significant difference between groups in major cardiovascular risk factors. Conclusion: These results demonstrate a major role of carotid thrombosis and inflammation in ischemic stroke in patients affected by carotid atherosclerotic disease.
基金ThisstudywassupportedbythegrantforKeyProjectofNationalNaturalScienceFoundationinChina (No39730170)andthegrantforGeneralProjectofNSFC (No 3 9770 810 )
文摘OBJECTIVE: To study whether recombinant adeno-associated virus (rAAV) mediated foreign gene, LacZ, could pass the blood brain barrier by intra-carotid artery delivery and express in vivo in ischemic brain of the focal embolic stroke rats to investigate a possibility of delivering foreign gene through carotid artery to treat acute ischemic stroke. METHODS: The carotid artery territory in 41 rats was embolized with or without arterial-like fibrin rich clots to make a model of focal embolic stroke rat. rAAV containing LacZ gene (rAAV-LacZ) was constructed in 293 cells by calcium phosphate cotransfection. The rats were assigned to one of the following treatments: 1 control (without embolism) groups, including PBS treated (n = 6), pLacZ treated (n = 6 ) and rAAV-LacZ treated (n = 6): 2 embolic groups, including embolism + PBS (n =7),embolism + pLacZ (n = 8) and embolism + rAAV-LacZ (n = 8). Brains were cryosectioned and kappa-Gal stain was performed at 2, 4, and 8 weeks, respectively, after transfection, and then infarct volume was measured and the percentage of LacZ staining-positive cells was calculated. RESULTS: In all the control groups and embolism + PBS treated animal, no kappa-Gal staining-positive cells were found, but in embolism + pLacZ (n = 8) and embolism+rAAV-LacZ groups a lot of kappa-Gal staining-positive cells were found. The expression cells were in the tissues around the infarction. The gene expression persisted only nearly four weeks in embolic group with pLacZ. In the embolic group with rAAV-LacZ the expression was very stable during the experiment course (eight weeks) and the percentage of the expressed cells was significantly higher than that of its contralateral areas at the same time points, respectively. CONCLUSIONS: The plasmid vector and rAAV could enter the brain through the ischemia-damaged blood barrier and foreign gene can be expressed in brain. The positive gene expression is mainly in the peripheral areas of the infarction. rAAV as a permanent expression vector may ultimately be used for gene therapy of human ischemia cerebravascular diseases.
