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1.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

2.
目的本研究运用磁共振弥散加权成像(DWI)技术动态评价大鼠脑缺血—再灌注损伤后不同时间脑损伤区DWI信号强度(SI)及表观扩散系数(ADC)的变化,结合组织学检测,分析损伤区组织学特征。方法健康成年SD雄性大鼠(n=80)随机分成8组,分别为脑缺血—再灌注1h、3h、6h、12h、1d、3d、7d组和假手术组,采用线栓法制作大鼠右侧大脑中动脉缺血—再灌注(MCAO/R)模型,Zea Longa评分评价神经功能损伤程度,Philips Achieva 3.0T MR扫描仪对假手术组和缺血—再灌注后不同时间点大鼠脑部行冠状位DWI扫描,在工作站上重建ADC图,测量基底核层面梗死灶DWI-SI和ADC值,计算相对ADC值(r ADC)和相对DWI-SI(r DWI-SI)值。2,3,5-氯化三苯基四氮唑(TTC)染色评价梗死体积的变化。苏木精—伊红染色观察组织形态学变化。结果假手术组动物麻醉苏醒后未见神经功能缺损,脑缺血—再灌注1h大鼠出现神经损伤,3h~1d时症状逐渐加重,3~7d时症状改善。假手术组DWI及ADC图均未见异常信号;MCAO/R后1h DWI上右侧纹状体及周围部分皮质区域出现高信号,相应部位ADC值降低,1h~1d DWI高信号范围随时间推移逐渐增大,信号强度逐渐增高,3~7d时开始降低;r ADC值随时间先降低后升高,6h达到最低,12h开始回升,1d时r ADC值较12h稍降低(P0.05),3d时r ADC升高,7d时与假手术组无明显差异(P0.05);1h~1d r DWI-SI持续升高,1d达最高峰,3~7d开始下降,7d时仍明显高于假手术组。苏木精—伊红染色显示假手术组右侧海马及皮质区结构未见明显异常;缺血—再灌注12h缺血侧海马区及皮质区出现可见部分浓染细胞和胞浆空泡形成,核固缩,但细胞排列尚好;1d时缺血侧神经元缺血损伤加重,细胞排列紊乱,细胞间隙增宽,出现大量胞浆空泡化,核固缩显著;3d时缺血侧海马区空泡化有所减轻。假手术组TTC染色未见梗死区域;脑缺血—再灌注1h可见右侧纹状体及周围少许皮质梗死;1h~1d梗死体积逐渐增大,1~3d时达到峰值,7d时梗死体积减小。1h~1d缺血侧脑水肿体积随时间持续增加,1d达到高峰,3d时开始下降,7d明显减轻。模型组各时间点神经功能评分与相应时间点基底核区梗死灶r DWI-SI呈显著性正相关(r=0.503,P=0.000);相应时间点脑梗死体积、水肿体积与r DWI-SI均呈显著性正相关(r=0.542,P=0.001;r=0.740,P=0.000)。结论磁共振弥散加权成像获得的DWI-SI及ADC值,对评价脑缺血再灌注损伤组织学特征具有高度的敏感性和特异性,对脑缺血—再灌注损伤后缺血区的动态改变具有直观的价值。  相似文献   

3.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

4.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

5.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

6.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

7.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

8.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

9.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

10.
目的 研究大鼠局灶性脑缺血再灌注区域信号转导子与转录激活子-3(STAT3)激活变化,探讨其与梗死面积变化的关系. 方法 99只雄性SD大鼠分为假手术组和缺血2 h、6 h再灌注不同时间组,线栓法建立大脑中动脉闭塞(MCAO)模型.各组动物于不同时间点处死取脑,取相应部位脑组织行TTC染色.采用免疫组化及免疫印迹法检测STAT3蛋白表达和磷酸化水平,分析其与梗死面积变化的相关性. 结果缺血后TTC染色可见部分右侧大脑半球失染呈白色.缺血6h组再灌注0 h较缺血2 h再灌注0 h TTC失染面积大.差异有统计学意义(P<0.05).缺血2 h再灌注24 h后失染面积较灌注0 h明显变小,差异有统计学意义(P<0.05).免疫组化定位:STAT3在胞浆中表达,磷酸化STAT3(P-STAT3)在胞核中表达.Western blot半定量分析结果:缺血再灌注不引起STAT3蛋白表达的变化,但P-STAT3表达增加,随着再灌注时间延长,24 h达到峰值.STATS激活的水平与TTC失染面积变化呈负性相关(缺血2 h组:r=-0.680,P<0.05;缺血6 h组:r=-0.672,P<0.05). 结论 脑缺血再灌注不同时间STAT3表达水平无明显变化,但可诱导缺血区域磷酸化水平增加,其激活水平与梗死面积相关.  相似文献   

11.

Objective

We prospectively investigated the correlation between diffusion tensor (DTI), dynamic susceptibility contrast (DSC) perfusion MRI metrics and Ki-67 labelling index in glioblastomas.

Methods

We studied seventeen patients who were operated on for glioblastoma. DTI and DSC MRI were performed within a week prior to surgical excision. Lesion/normal ratios were calculated for the apparent diffusion coefficient (ADC), fractional anisotropy (FA), relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and relative mean transit time (rMTT) ratio. In the excised tumour specimens Ki-67 antigen expression was evaluated by the MIB-1 immunostaining method.

Results

A significant correlation was observed between Ki-67 index and ADC ratio (r = −0.528, p = 0.029) and FA ratio (r = 0.589, p = 0.012). rCBV and rMTT presented a trend towards significant correlation with Ki-67 index (r = 0.628, p = 0.07 and r = 0.644, p = 0.06 respectively). There was a trend towards better survival for patients with gross total tumour excision and FA values lower than 0.48 (p = 0.1 and p = 0.09 respectively). No significant correlation was found between ADC ratio, rCBV, rCBF, rMTT and overall survival.

Conclusion

ADC ratio, FA ratio, rCBV and rMTT tumour/normal tissue ratios may represent indicators of glioma proliferation. FA values may hold promise for predicting survival in patients with glioblastoma.  相似文献   

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Schizophrenia, once considered a psychological malady devoid of any organic brain substrate, has been the focus of intense neuroimaging research. Findings reveal mild but generalized tissue loss as well as more selective focal loss. It is unclear whether these abnormalities reflect neurodevelopmental or neurodegenerative processes, or some combination of each; current evidence favors a preponderance of neurodevelopmental abnormalities. The pattern of brain abnormalities is also influenced by environmental and genetic risk factors, as well as by the course (and possibly even treatment) of this illness. These findings are described in this article.  相似文献   

14.
15.
This study in children born extremely preterm (EP; <28 weeks’ gestational age) or extremely low birth weight (ELBW; <1,000 g) investigated whether adaptive working memory training using Cogmed® is associated with structural and/or functional brain changes compared with a placebo program. Ninety‐one EP/ELBW children were recruited at a mean (standard deviation) age of 7.8 (0.4) years. Children were randomly allocated to Cogmed or placebo (45‐min sessions, 5 days a week over 5–7 weeks). A subset had usable magnetic resonance imaging (MRI) data pretraining and 2 weeks posttraining (structural, n = 48; diffusion, n = 43; task‐based functional, n = 18). Statistical analyses examined whether cortical morphometry, white matter microstructure and blood oxygenation level‐dependent (BOLD) signal during an n‐back working memory task changed from pretraining to posttraining in the Cogmed and placebo groups separately. Interaction analyses between time point and group were then performed. There was a significant increase in neurite density in several white matter regions from pretraining to posttraining in both the Cogmed and placebo groups. BOLD signal in the posterior cingulate and precuneus cortices during the n‐back task increased from pretraining to posttraining in the Cogmed but not placebo group. Evidence for group‐by‐time interactions for the MRI measures was weak, suggesting that brain changes generally did not differ between Cogmed and placebo groups. Overall, while some structural and functional MRI changes between the pretraining and posttraining period in EP/ELBW children were observed, there was little evidence of training‐induced neuroplasticity, with changes generally identified in both groups. Trial registration Australian New Zealand Clinical Trials Registry, anzctr.org.au ; ACTRN12612000124831.  相似文献   

16.
边缘系统涉及人类大脑半球的较大区域,包括岛叶、额叶眶面、半球内侧面的扣带回.颞极和颢叶内侧面的部分结构以及与这些区域相关的皮质结构.边缘系统肿瘤常见于中青年,癫痫发作常是其首发和惟一症状,病理上以低级别胶质瘤及其他良性肿瘤为主[1].  相似文献   

17.
BACKGROUND AND PURPOSE: In middle cerebral artery (MCA) stroke, ischemia usually is unevenly distributed within the MCA territory. We sought to investigate which brain structures are critical for the acute neurological deficit in severe MCA stroke. METHODS: We used magnetic resonance (MR) imaging and statistical parametric mapping in 64 consecutive stroke patients (64 +/-13 years) to study the pattern of the initial perfusion abnormality. RESULTS: Patients with lesion progression had more severe time-to-peak (TTP) abnormalities (P < .0001) in the inferior frontal gyrus, superior temporal gyrus, insula, and underlying hemispheric white matter than those with lesion regression. Also, patients with lesion progression had more severe T2 abnormalities on day 8 than those with lesion regression. In contrast, the changes of water diffusion were similar among the two groups resulting in a perfusion-diffusion mismatch in lesion progression. TTP-lesions were related to the neurological deficit score (r(s)=-0.563, P < .0001), T2-lesions (r= 0.686, P < .0001), and cerebral artery abnormalities assessed on MR-angiography (r(s)= 0.399, P < .01). CONCLUSIONS: In major MCA, stroke ischemia was most severe in the central portion of the MCA territory. It is suggested that involvement of hemispheric white matter accentuated the neurological deficit probably by affecting cortico-cortical and cortico-subcortical fibers.  相似文献   

18.
Introduction Diffusion-weighted imaging (DWI) is mainly used in acute stroke, and signal evolution in the acute phase has been studied extensively. However, patients with a minor stroke frequently present late. Recent studies suggest that DWI may be helpful at this stage, but only very few published data exist on the evolution of the DW-signal in the weeks and months after a stroke. We performed a follow-up study of DWI in the late stages after a minor stroke. Methods 28 patients who presented 48 hours to 14 days after a minor stroke underwent serial MRI at baseline, 4 weeks, 8 weeks, 12 weeks, 6 months and ≥9 months after their event. Signal intensity within the lesion was determined on T2-weighted images, DW-images and the Apparent Diffusion Coefficient (ADC) map at each time-point, and ratios were calculated with contralateral normal values (T2r, DWIr, ADCr). Results T2r was increased in all patients from the beginning, and showed no clear temporal evolution. ADCr normalized within 8 weeks in 83% of patients, but still continued to increase for up to 6 months after the event. The DW-signal decreased over time, but was still elevated in 6 patients after ≥6 months. The evolution of ADCr and DWIr showed statistically highly significant inter-individual variation (p < 0.0001), which was not accounted for by age, sex, infarct size or infarct location. Conclusion The ADC and the DW-signal may continue to evolve for several months after a minor ischaemic stroke. Signal evolution is highly variable between individuals. Further studies are required to determine which factors influence the evolution of the ADC and the DW-signal. Received in revised form: 14 April 2006  相似文献   

19.
Laser speckle contrast imaging (LSCI) provides a rapid characterization of cortical flow dynamics for functional monitoring of the microcirculation. The technique stems from interactions of laser light with moving particles. These interactions encode the encountered Doppler phenomena within a random interference pattern imaged in widefield, known as laser speckle. Studies of neurovascular function and coupling with LSCI have benefited from the real-time characterization of functional dynamics in the laboratory setting through quantification of perfusion dynamics. While the technique has largely been relegated to acute small animal imaging, its scalability is being assessed and characterized for both chronic and clinical neurovascular imaging.  相似文献   

20.
目的:建立小型猪脑缺血模型,并通过数字减影血管造影(DSA)、磁共振弥散加权成像(DWI)、磁共振灌注加权成像(PWI)进行评价。方法:6月龄小型猪14头采用双侧咽升动脉气囊阻断法制作脑缺血模型,于阻断前、阻断期及再灌注0.5h、2h分别给予DSA、DWI、PWI和MRI评价。结果:阻断期DSA可见双侧咽升动脉及其分支血管血流阻断,再灌后0.5h及2h双侧咽升动脉及其分支血管血供恢复;阻断前DWI、PWI均未见异常,阻断期及再灌注各时间点DWI、PWI发现异常高信号,表观弥散系数(ADC)值和局部脑血流(rCBF)下降,达峰时间(rTTP)延迟;T1WI和T2WI在阻断前、阻断期和再灌后各时间点均未发现异常信号。结论:通过磁共振影像学评价证明双侧咽升动脉气囊阻断法制作小型猪脑缺血模型是稳定的、可重复的,此方法可造成程度较为一致的小型猪缺血性脑损伤。  相似文献   

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