大鼠脑缺血再灌流时神经元损伤与星形胶质细胞的反应

为探讨星形胶质细胞在缺血性神经元损伤中的作用及其与神经元损伤的关系 ,本实验阻塞大鼠大脑中动脉 2 h,再灌流0 .5～ 48h建立短暂局灶性脑缺血模型 ,进行 H-E染色 ;通过胶质原纤维酸性蛋白和细胞核增殖抗原免疫组化单重或双重反应 ,TU NEL和胶质原纤维酸性蛋白免疫组化双重反应观察了神经元和星形胶质细胞的反应。结果表明 :再灌流 2 4h缺血区面积最大 ,再灌流 6h开始出现神经元不可逆变性 ,2 4h梗塞成熟 ;星形胶质细胞表现为反应性、营养不良性和退形变三种不同的形态特点。再灌流 48h时星形胶质细胞数量开始增多。 48h之内星形胶质细胞无增生 ,且有少量星形胶质细胞凋亡。这些结果提示脑缺血时星形胶质细胞反应与神经元损伤密切相关 ,反应性星形胶质细胞是其积极应答神经元损伤的结果 ,在维持神经元存活中起作用。     

Human physiological responses to immersion into water of different temperatures

To differentiate between the effect of cold and hydrostatic pressure on hormone and cardiovascular functions of man, a group of young men was examined during 1-h head-out immersions in water of different temperatures (32°C, 20°C and 14°C). Immersion in water at 32°C did not change rectal temperature and metabolic rate, but lowered heart rate (by 15%) and systolic and diastolic blood pressures (by 11%, or 12%, respectively), compared to controls at ambient air temperature. Plasma renin activity, plasma cortisol and aldosterone concentrations were also lowered (by 46%, 34%, and 17%, respectively), while diuresis was increased by 107%. Immersion at 20°C induced a similar decrease in plasma renin activity, heart rate and systolic and diastolic blood pressures as immersion at thermoneutrality, in spite of lowered rectal temperature and an increased metabolic rate by 93%. Plasma cortisol concentrations tended to decrease, while plasma aldosterone concentration was unchanged. Diuresis was increased by 89%. No significant differences in changes in diuresis, plasma renin activity and aldosterone concentration compared to subjects immersed to 32°C were observed. Cold water immersion (14°C) lowered rectal temperature and increased metabolic rate (by 350%), heart rate and systolic and diastolic blood pressure (by 5%, 7%, and 8%, respectively). Plasma noradrenaline and dopamine concentrations were increased by 530% and by 250% respectively, while diuresis increased by 163% (more than at 32°C). Plasma aldosterone concentrations increased by 23%. Plasma renin activity was reduced as during immersion in water at the highest temperature. Cortisol concentrations tended to decrease. Plasma adrenaline concentrations remained unchanged. Changes in plasma renin activity were not related to changes in aldosterone concentrations. Immersion in water of different temperatures did not increase blood concentrations of cortisol. There was no correlation between changes in rectal temperature and changes in hormone production. Our data supported the hypothesis that physiological changes induced by water immersion are mediated by humoral control mechanisms, while responses induced by cold are mainly due to increased activity of the sympathetic nervous system. Accepted: 4 February 1999     

Presentation,etiology and treatment outcome of neovascular glaucoma in Ekiti state,South Western Nigeria

BackgroundNeovascular glaucoma (NVG), a form of secondary glaucoma has varying causes across geographical locations.ObjectiveThe objective of this study was to determine the presentation, aetiology, and outcome of treatment of patients with NVG in a Nigerian tertiary hospital.MethodA retrospective review of records of all cases of NVG seen over a 5year period was carried out. Demographic characteristics, presenting visual acuity and coexisting ocular and systemic conditions were noted. Data were analysed with Statistical Package for Social Sciences (SPSS) version 25.Results29 eyes of patients with NVG were analysed. Most of the patients (89.70%) presented with visual acuity less than 3/60 in the affected eye. All patients except one were treated with anti-glaucoma medications while only 9(31%) consented to and received anti-vascular endothelial growth factor. No patient had improvement in visual acuity despite resolution of other symptoms at 12week follow up.ConclusionNVG though not as common as other forms of glaucoma accounted for a large proportion of monocular blindness in the affected eyes at presentation. There is need for health promotion and education among our people on the need for early preventive eye check practices.     

飞龙掌血水提物对心肌缺血兔心功能和血液动力学的影响

目的:观察飞龙掌血(Toddalia asiatica Lam)水提物(飞龙一号,F01)对急性心肌缺血动物模型心脏功能和血液动力学的影响。方法:新西兰兔作不开胸膜冠脉左前降支高位结扎造成急性心肌缺血, 观测结扎后及F01 ip对动物心功、血液动力学的影响。结果:冠脉左前降支结扎后,LVEDP显著升高(P＜0.05),t-dp/dt max 无明显变化,其余各项参数均明显降低(P＜0.05或P＜0.01)。F01(268 mg/kg)腹腔注射后,除有关左室作功和心肌耗氧的参数(HR、TTI和TTI×HR)继续降低外,其余各项参数的变化均显著逆转,恢复或接近结扎前的水平, 用药后1.5 h的作用较0.5 h更明显。结论:F01可显著减少急性缺血心肌的作功和耗氧,通过纠正心脏对氧的供需平衡失调,改善心脏收缩、舒张功能和泵血功能,从而发挥对缺血心肌的保护作用。     

bFGF对局灶性脑缺血大鼠脑组织ERK表达的影响

目的研究大鼠脑缺血再灌注后对胞外信号调节激酶(extracellular signal-regulated kinase,ERK)表达的影响,探讨碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)对脑组织缺血再灌注神经元ERK的调节作用及机制。方法应用线栓法制作大鼠局灶性脑缺血再灌注模型,大脑中动脉阻塞2 h再灌注损伤24 h,采用TUNEL法、免疫组化检测海马及皮质内神经元凋亡和ERK的表达。结果 sham组鼠海马及大脑皮质偶见凋亡细胞,大脑皮质及海马神经元内少见ERK免疫反应阳性细胞;I/R组鼠海马及皮质神经元凋亡增加,缺血再灌注损伤后大脑皮质及海马神经元内ERK阳性表达明显高于假手组;bFGF组鼠海马及皮质神经元凋亡减少,皮质及海马神经元内ERK表达较I/R组明显增加。结论 bFGF显著减少缺血神经元凋亡,上调脑缺血诱导的ERK表达,对脑缺血再灌注海马及皮质神经元的具有保护作用。     

c-Jun氨基末端激酶在脑缺血再灌注损伤中的作用

在生物体内,丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)是信号从细胞表面转导至细胞核内部的重要传递者,是一类丝/苏氨酸残基的蛋白激酶。目前在真核生物细胞中,已明确了4条MAPK信号转导通路,即细胞外信号调节蛋白激酶(extracellular signal-regulated protein kinases,ERK)通路、c-Jun氨基末端激酶(c-Jun N-terminal kinase,JNK)通路、p38通路及ERK5通路。JNK信号通路作为MAPK信号通路中重要的通路之一,参与了多种生理、病理过程,目前诸多研究表明其在脑缺血/再灌注损伤过程中尤其是程序性细胞死亡过程中起着重要的调控作用,本文就近年来对JNK通路的研究及JNK在脑缺血再灌注诱导的细胞凋亡中的作用及机制作一综述。     

预适应和后适应对缺血/再灌注损伤大鼠心肌组织炎症因子的影响

目的:观察缺血预适应(IPC)、缺血后适应(IPOC)对大鼠心肌组织缺血/再灌注(I/R)损伤后Toll样受体(TLR)及下游炎症因子的影响。方法:SD大鼠60只,通过SPSS软件随机分为假手术组(冠状动脉前降支下置线不结扎,n=15);I/R组(冠状动脉前降支结扎30min,再灌注60min,n=15);IPC组(冠状动脉前降支3次3min/5min的缺血/再灌注循环,然后结扎30min后,再持续灌注60min,n=15);IPOC组(冠状动脉前降支结扎30min,3次10s的缺血/再灌注循环,再持续灌注60min,n=15)。实验结束后测定大鼠血清肌酸激酶同工酶(CK-MB)和肌钙蛋白T(cTNT)水平;氯化硝基四氮唑兰(NBT)染色测定大鼠左室心肌梗死面积;免疫组织化学法测定心肌组织TLR-2、4的表达;酶联免疫吸附法测定心肌组织白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、单核细胞趋化蛋白-1(MCP-1)和肿瘤坏死因子-α(TNF-α)的含量。结果:与I/R组比较,IPC组、IPOC组大鼠血清CK-MB和cTNT水平显著降低(P<0.01),心肌梗死面积显著减小(P<0.01),心肌组织TLR-2、4表达和炎症因子IL-6、IL-1β、MCP-1、TNF-α含量显著下降(P<0.05,P<0.01);与IPC组比较,IPOC组减小I/R大鼠心肌梗死面积,降低血清CK-MB及心肌组织IL-6等作用和IPC组无显著差异(P>0.05)。结论:IPOC与IPC同样具有减轻心肌I/R损伤程度和缩小心肌梗死范围等作用,抑制TLR-2、4的表达可能是其保护I/R心肌的一个重要途径。     

心肌缺血再灌注损伤中细胞焦亡的研究进展

细胞焦亡是近年来发现并被证实的一种新的细胞程序性死亡方式,它的特征是依赖半胱氨酸天冬氨酸酶1(cysteinyl aspartate specific proteinase 1,caspase-1)并伴随大量炎症因子的释放。细胞焦亡参与了包括感染性疾病在内的多种疾病的病理生理过程。作为一种新的调节性细胞死亡方式,近年来...     

感冒茶治疗风热感冒临床观察

目的探讨感冒茶治疗风热感冒（挟湿型）的临床疗效。方法将2006年3月至2006年9月门诊确诊为风热感冒（挟湿型）患者依据就诊先后时间随机分为2组,对照组40例服用银翘解毒软胶囊;治疗组66例服用感冒茶颗粒,3d后观察疗效。结果临床治疗66例,总有效率达92.59%,明显优于对照组（76.19%）。结论应用感冒茶颗粒治疗风热感冒（挟湿型）具有较理想的效果,值得临床推广应用。     

Autophagy： a double-edged sword for neuronal survival after cerebral ischemia

Evidence suggests that autophagy may be a new therapeutic target for stroke, but whether acti- vation of autophagy increases or decreases the rate of neuronal death is still under debate. This review summarizes the potential role and possible signaling pathway of autophagy in neuronal survival after cerebral ischemia and proposes that autophagy has dual effects.