新生大鼠缺氧缺血脑损伤后bcl-x mRNA的表达

目的　探讨新生大鼠脑缺氧缺血后死亡相关基因 bcl- x m RNA表达的变化及其与脑缺氧缺血所致细胞凋亡的关系。方法　通过建立新生大鼠缺氧缺血性脑病动物模型 ,应用快速竞争性 RT- PCR技术对缺氧缺血后不同时间点的缺血侧大脑组织中 bcl- x m RNA的表达进行半定量分析 ,并在相同缺血基础上观察缺氧 1.5小时、2 .5小时和 3.5小时对 bcl- x m RNA表达的影响。结果　缺氧缺血后 ,新生大鼠脑 bcl- xs(bcl-x短型 ) m RNA的表达自缺氧结束后即刻即有明显增强 ,2 4小时达高峰 ,此后逐渐下降 ,7天时回复至正常基线水平。随着缺氧时间的延长即缺氧程度的加重 ,bcl- xs m RNA的表达有增强趋势 ,缺氧 1.5小时组、2 .5小时组及 3.5小时组之间 bcl- xs m RNA表达水平的差异均具显著性意义 (P<0 .0 1)。bcl- xs m RNA的表达高峰与缺氧缺血后脑细胞凋亡的高峰时相相吻合。缺氧缺血对 bcl- xl(bcl- x长型 ) m RNA的表达无影响。结论缺氧缺血可诱导新生大鼠脑 bcl- xs m RNA表达增强。在一定范围内 ,其表达强度与缺氧程度成正相关。 bcl-xs过表达在缺氧缺血后脑细胞凋亡的调控过程中起着一定的作用     

脑缺氧缺血后新生大鼠bcl-2 mRNA的表达

目的　探讨新生大鼠脑缺氧缺血后bcl 2mRNA表达的变化及其与脑缺氧缺血所致细胞凋亡的关系。方法　通过建立新生大鼠缺氧缺血性脑病动物模型 ,应用快速竞争性RT PCR技术对缺氧缺血后不同时间点的实验侧大脑组织中bcl 2mRNA的表达进行半定量分析 ,并在相同缺血基础上观察缺氧 1 5h、2 .5h和 3 5h对bcl 2mRNA表达的影响。结果　缺氧缺血后 ,新生大鼠脑bcl 2mRNA的表达自缺氧结束后 6h开始明显增强 ,1 2h达高峰 ,2 4h回落至较低水平 ,至 72h已基本检测不到。随着缺氧时间的延长即缺氧程度的加重 ,bcl 2mRNA的表达有增强趋势 ,但在缺氧 1 5h组和 2 5h组之间无显著性差异 ,而缺氧 1 5h组或 2 5h组与缺氧 3 5h组之间均具显著性差异 (P <0 0 1 ) ,后者表达更强。结论　缺氧缺血可诱导新生大鼠脑bcl 2mRNA的表达。在一定范围内 ,缺氧越严重 ,其表达越强。但由于严重损伤时蛋白质的合成常受到抑制 ,因此在判断bcl 2mRNA与凋亡的关系时必须结合其产物bcl 2蛋白的合成情况进行分析。     

大鼠局灶性脑缺血后的细胞凋亡现象

目的 :研究大鼠局灶性脑缺血再灌注后的细胞凋亡现象及其时间和解剖分布。方法 :雄性SD大鼠 3 0只 ,用改良Longa法制左右侧大脑中动脉梗死模型 ,根据缺血时间不同进行随机分组 ;用电子显微镜和TUNEL染色检测细胞凋亡。结果 :电镜和光镜下显示 ,脑缺血后有DNA断裂和细胞凋亡现象 ,TUNEL染色示随缺血时间延长 ,凋亡细胞数目逐渐增加 ,缺血 1h时为每张切片 (83± 2 1)个 ,2h时为 (2 3 3± 3 6)个 ,4h时为 (3 73± 3 0 )个 (P <0 0 1) ;凋亡细胞主要分布在梗死灶边缘区的内侧。结论 :脑组织缺血后存在着细胞凋亡现象 ,凋亡在梗死灶的发展过程中起一定作用。     

神经生长因子对大鼠局灶性脑缺血再灌注后细胞凋亡的影响

目的　探讨大鼠局灶性脑缺血再灌注后神经生长因子 (NGF)对细胞凋亡的影响。方法　应用原位缺口末端标记 (TUNEL)法检测大鼠大脑中动脉线栓法阻断 2h ,再灌注 2 2h ,细胞凋亡情况及静脉注射NGF对细胞凋亡的影响。结果　缺血 2h ,再灌注 2 2h ,梗死区可见大量凋亡细胞 (2 4 8.4 2± 2 4 .37) ,静脉注射NGF后梗死区凋亡细胞明显减少 (190 .2 5± 2 5 .4 7) (P <0 0 1)。结论　局灶性脑缺血再灌注后细胞凋亡增加 ,静脉给予NGF可减少脑细胞凋亡     

大鼠局灶性脑缺血再灌注后CAD表达与细胞凋亡的关系

目的　探讨大鼠局灶性脑缺血再灌注后缺血半暗带 Caspase-3激活的 DNA酶 (CAD)基因的表达变化与细胞凋亡的关系。方法　线栓法建立大鼠大脑中动脉闭塞 (MCAO)及再通模型。应用 RT-PCR技术检测MCAO再通后不同时相缺血半暗带皮质 CAD基因的表达 ,同时利用 TU NEL法观察对应区域细胞凋亡的动态变化规律。结果　脑缺血再灌注 6h,半暗带皮质 CAD m RNA显著升高 ,密度比值为 0 .74± 0 .0 4,再灌注 2 4h达到高峰 (1.13± 0 .11)。对应各时相均可见神经细胞凋亡 ,凋亡细胞以再灌注 48h组为最高 (113 .10± 13 .88)。结论　脑缺血再灌注可致 CAD基因表达上调 ,可能参与了缺血后神经细胞凋亡过程     

新生大鼠缺氧缺血性脑损伤时Bcl-2和P53蛋白的表达

目的研究Bcl-2的P53蛋白在新生儿缺氧缺血性脑损伤(HIBD)中的表达及与细胞凋亡的关系。方法将新生7日龄Wistar大鼠制成HlBD模型，应用免疫组织化学-SP法及原位缺口末端标记(TUNEL)研究Bcl-2和P53蛋白在新生大鼠及缺氧缺血(HI)后脑中表达及与凋亡的关系。结果新生大鼠HIBD时凋亡与坏死并存，以凋亡为主。Bcl-2免疫蛋白在正常新生大鼠脑内广泛表达(+～++++)；Hl后脑病变处Bcl-2免疫强度明显下降(-～+)；P53蛋白在正常新生大鼠脑内基本无表达；HI后病变部位散在分布阳性凋亡细胞。结论Hl后Bcl-2免疫表达减弱，P53的免疫表达增强，提示Bcl-2可抑制凋亡，P53可能促进凋亡。     

局灶脑缺血后胰岛素对c-fos、c-jun基因表达的影响

目的　观察胰岛素对局灶缺血性脑组织 c- fos、c- jun基因表达的影响。方法　 30只肾血管性高血压大鼠随机分 4组 ,在大脑中动脉闭塞 (MCAO)后即予胰岛素 (2 .1IU / kg,A组 )、葡萄糖和胰岛素 (2 .1IU / kg,B组 ;4.5 IU / kg,C组 )、生理盐水 (D组 ) ,采用原位杂交技术检测各组 MCAO后 3h脑组织 c- fos、c- jun基因的表达。结果　与其它组比较 ,A组血糖下降明显 (P<0 .0 1) ,MCAO后 1h、2 h、3h分别为 3.80± 0 .3mm ol/ L、3.6 8± 0 .3mm ol/L、3.6 9± 0 .3mm ol/ L。 c- fos m RNA被诱导出现于缺血侧皮层和尾壳核 ,C组 c- fos m RNA明显增加 (P<0 .0 1) ,皮层和尾壳核的灰度为 12 3.5 8± 8.72、141.0 8± 8.49;c- jun m RNA仅出现于缺血侧皮层 ,A、B、C组的 c- jun m RNA均增加明显 ,灰度分别为 171.82± 7.33、172 .5 6± 7.91、15 5 .0 9± 7.91,其中 C组的增加更为显著 (P<0 .0 1)。结论　胰岛素促进缺血脑组织 c- fos、c- jun基因表达可能是其神经保护作用机制之一。     

新生大鼠缺氧缺血性脑损伤后CIRP表达与意义

目的观察新生大鼠缺氧缺血性脑损伤(HIBD)后冷诱导RNA结合蛋白(CIRP)表达的变化情况。方法将40只7日龄新生SD大鼠随机分为假手术组和HIBD组,分别采用real-time PCR及免疫组织化学方法检测假手术组和HIBD后不同时间点(6、12、24和48h)CIRP在大鼠脑皮质与海马表达的变化。结果利用免疫组化和real-time PCR检测发现,大鼠脑皮质的CIRP蛋白和CIRP mRNA表达呈持续降低趋势,HIBD后6、12 h开始减少;24~48h下降更为明显。海马CIRP蛋白和CIRP mRNA表达则表现为6 h先升48h后降。结论CIRP参与了新生大鼠脑缺氧缺血的应激过程,可能与缺氧缺血性脑损伤后的脑水肿及神经元凋亡相关。     

达纳康抑制大鼠局灶性脑缺血再灌注损伤后P~(53)蛋白表达及细胞凋亡的研究

目的　研究达纳康在大鼠局灶性脑缺血再灌注损伤中的脑保护作用及其分子机制。方法　采用线栓法建立大鼠大脑中动脉 ( MCAO)缺血 1h再灌注 2 4 h模型 ,18只雄性大鼠随机分为假手术组、生理盐水对照组和达纳康治疗组 ,每组 6只。采用 Zea- L onga评分法观察神经功能缺损程度 ,采用免疫组织化学方法、TUNEL 法分别观察各组 P53蛋白表达和细胞凋亡。结果　假手术组神经功能缺失评分为 0分 ,高倍视野下无 P53蛋白染色阳性细胞及凋亡细胞 ;达纳康治疗组神经功能缺失评分 ( 0 .4 8± 0 .3 7分 )、P53蛋白染色阳性细胞数 ( 5 .16± 1.84个 /高倍视野 )、凋亡细胞数 ( 4 .18± 1.2 1个 /高倍视野 )均较生理盐水对照组 ( 2 .76± 0 .82分、10 .4 3± 1.5 6个 /高倍视野、8.16± 1.5 0个 /高倍视野 )显著减少 ( P<0 .0 1)。结论　达纳康可明显减轻局灶性脑缺血再灌注损伤 ,其抑制神经细胞P53蛋白的表达 ,进而抑制细胞凋亡 ,是其脑保护作用的分子机制之一。     

高血压脑出血血肿周围脑组织缺氧诱导因子-1α的表达及意义

目的研究高血压脑出血患者血肿周围脑组织缺氧诱导因子-1α的表达及其与继发性神经元损伤的关系。方法选择行血肿清除术的脑出血患者32例,选取手术过程中获得的血肿周围脑组织,采用免疫组织化学技术、HE染色及TUNEL染色方法检测缺氧诱导因子-1α的表达及凋亡细胞的变化。结果出血4h,血肿周围脑组织即可见散在缺氧诱导因子-1α表达的神经元[(2.8±0.8)个/高倍视野],24~48h时达到高峰[(12.5±3.9)个/高倍视野],49~72h高表达持续存在[(12.2±1.8)个/高倍视野];出血4h可见神经元细胞及血管内皮细胞肿胀,出血12h可检测到明显的凋亡细胞[阳性细胞数为(11.2±4.1)个/高倍视野],24~48h凋亡细胞明显增多[(29.7±8.4)个/高倍视野],49~72h达到高峰[(33.2±4.3)个/高倍视野]。缺氧诱导因子-1α的表达与凋亡细胞呈正相关性(r=0.788,t=7.02,P<0.01)。结论脑出血后血肿周围神经元发生一系列形态学变化,其演变规律与缺氧诱导因子-1α的表达有密切相关性。     

Cerebral blood flow and cerebral hematocrit in patients with cerebral ischemia measured by single-photon emission computed tomography

Abstract– Single-photon emission computed tomography (SPECT) was used for the measurement of regional cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral hematocrit (Hct). CBF was measured using N-isopropyl-p-I-123-Iodoamphetamine. CBV was measured by both RBC tracer (Tc-99m RBC) and plasma tracer (Tc-99m human serum albumin) and cerebral hematocrit (Hct) was calculated. In normals, the cerebral-to-large vessel Hct ratio was 75.9%. Isovolemic hemodilution in patients with high Hct tended to increase the cerebral-to-large vessel Hct ratio. Low CBF, high CBV and slow cerebral blood mean transit time (MTT by dynamic CT scanning) was seen during the acute stage of completed infarction and during the symptom-free interval of TIA. Cerebral Hct was increased in the ischemic region of poor prognosis.     

急性脑卒中患者血清红细胞生成素水平改变及其意义

目的探讨急性脑卒中患者血清红细胞生成素(EPO)水平改变及其临床意义。方法应用放射免疫法检测60例脑梗死(脑梗死组)、45例脑出血(脑出血组)和40例其他神经系统疾病患者(对照组)的血清EPO水平。用美国国立卫生研究院卒中量表(NIHSS)对急性脑卒中患者进行评分。结果脑梗死组和脑出血组血清EPO水平[(1.64±0.41)ng/ml,(1.59±0.54)ng/ml]显著高于对照组[(1.17±0.86)ng/ml](均P<0.05),脑梗死组及脑出血组的NIHSS评分[(10.42±3.75)分,(11.58±4.16)分]与血清EPO水平呈负相关(r=-0.482,r=-0.537,均P<0.05)。结论急性脑卒中患者的血清EPO水平明显升高,并且病情越重的患者血清EPO水平越低。     

急性脑梗死患者血小板数目的变化

观察50例急性脑梗死患者血小板数目和血小板膜表面α-颗粒膜蛋白（GMP-140）水平的动态变化,并就梗死面积大小,进行了相关分析。结果板膜表面GMP-140分子数在急性脑梗死早期明显增高,第二天达到高峰。两者均在5～7天恢复正常。主干支大灶性梗死较穿通支小灶性梗死血小板数目明显减少,而血小板膜表面α-颗粒膜蛋白（GMP-140）明显增高。死亡者血小板数目减少更显著,表明血小板直接参与了急性脑梗死的病理过程。     

GMl治疗61例急性脑卒中的疗效观察

目的:评价GMI治疗急性脑卒中(脑出血和脑梗塞)的疗效。方法:130例急性脑卒中病例随机分成两组。应用GMl组(61例)为治疗组,未用GMl组(69例)为对照组。治疗组除应用GMl外,两组治疗基本相同。观察两组治疗前、治疗2周后、治疗4周后的NDS(脑卒中患者临床神经功能缺损程度评分量表)和ADL(日常生活量表),并进行评分比较。结果:治疗前两组NDS和ADL评分比较无统计学差异,治疗2周、4周后有明显统计学差异。治疗组中治疗前与治疗2周、4周后比较有显著性差异,而治疗2周与4周后比较无统计学差异。结论:急性脑卒中病人应用GMI可明显改善临床症状,降低致残率,提高患者的生活自理能力。     

胰岛素抵抗与正常血压脑出血及脑梗塞关系的探讨

为研究胰岛素抵抗与脑出血、脑梗塞的关系,测定了正常血压脑出血41例、正常血压脑梗塞51例及对照组39例的血清胰岛素与血糖比值I/G,结果显示:三组I/G分别为6.3098±8.3268,5.1867±3.0069和2.4091±1.1374(means±SD)。正常血压脑出血组与对照组比较P<0.01。正常血压性脑梗塞组与对照组比较P<0.05。认为胰岛素抵抗是脑出血、脑梗塞的危险因素。     

GM1治疗61例急性脑卒中的疗效观察

目的：评价GM1治疗急性脑卒中（脑出血和脑梗塞）的疗效。方法：130例急性脑卒中病例随机分成两组，应用GM1组（61例）为治疗组，未用GM1组（69例）为对照组。治疗组除应用GM1外，两组治疗基本相同。观察两组治疗前、治疗2周后、治疗4周后的NDS（脑卒中患者临床神经功能缺损程度评分量表）和ADL（日常生活量表），并进行评分比较。结果：治疗前两组NDS和ADL评分比较无统计学差异，治疗2周、4周后有明显统计学差异。治疗组中治疗前与治疗2周、4周后比较有显著性差异，而治疗2周与4周后比较无统计学差异。结论：急性脑卒中病人应用GM1可明显改善临床症状，降低致残率，提高患者的生活自理能力。     

脑梗死静脉溶栓治疗后出血性转化临床分析

目的探讨急性脑梗死患者溶栓治疗后出血性转化(hemorrhagic transformation,HT)的危险因素以及继发HT患者的溶栓后并发症。方法回顾性分析62例经静脉溶栓治疗的急性脑梗死患者的临床资料,结合文献选择溶栓后继发HT的危险因素,包括年龄、性别、高血压、糖尿病、心功能不全史、脑卒中史、有无早期CT缺血改变、是否大面积脑梗死、是否心源性脑栓塞、发病至溶栓时间、溶栓药物、溶栓前NIHSS评分、溶栓前血糖水平、溶栓后3d内最低纤维蛋白原水平、血小板计数、肌酐水平等进行分析,对单因素分析法发现有统计学差异的危险因素进一步行Logistic回归分析。结果单因素分析发现,与无HT组相比,继发HT组年龄较大(P<0.01),溶栓前血糖水平(P<0.05)、溶栓后6h和12h的收缩压和舒张压较高(均P<0.05),大面积脑梗死发病至溶栓时间>3h、有早期CT缺血改变的患者比例高(均P<0.05)。Logistic多因素回归分析发现高龄(OR:1.129,P<0.05)、溶栓时间>3h(OR:2.592,P<0.05)、早期CT有缺血改变(OR:1.728,P<0.05)是继发HT的危险因素。继发HT组出现颅外出血并发症(52.2%vs 20.5%,χ2=6.637,P<0.05)、重度脑水肿(30.4%vs 5.1%,χ2=5.567,P<0.05)和脑疝形成(26.1%vs 2.6%,P<0.05)的比例更高。结论急性脑梗死患者静脉溶栓后HT的发生率高,高龄、发病至溶栓时间>3h和早期CT缺血改变是HT的危险因素。     

Attitudes in the management of acute ischaemic cere-brovascular accident and cerebral haemorrhage in Latin America: a multinational study

ABSTRACT— Eleven neurologists (the Collaborative Group) from 7 Latin American countries interviewed 73 of their peers (respondents) with a questionnaire containing points on history-taking, investigations performed, and treatment. The obvious methodological pitfalls of this method are discussed. It was felt, nevertheless, that with judicious interpretation of the answers a fair reflection of reality can be obtained. Items in the history which are less frequently enquired for were alcohol intake just before a stroke, known abnormalities in the blood picture, and intermittent claudication. Amongst less frequently performed investigations were Doppler study of carotids, angiography, lumbar puncture, echocardiography ordered without the indication of a cardiologist, and EEG. Regarding treatment, steroids were preferred by a large majority in the treatment of cerebral oedema. In other items two thirds or more of respondents reached agreement except when dealing with high blood pressure on admission, the use of aspirin in acute ischaemic non-cardiogenic stroke and the use of anticoagulants in stroke considered to be progressing. No differences by country or years of experience were found. The management of affluent and poorer patients was more even than might be expected, most telling differences being CT scanning and anticoagulation.     

Hemodynamic significance of internal carotid artery disease

Neurologic symptoms in the region of an internal carotid artery stenosis are considered to be embolic in most instances. Only in a subgroup has carotid occlusive disease with impairment of the collateral supply, caused a state of hemodynamic failure with marked reduction of perfusion pressure. Though unproven, it is reasonable to assume that without surgical intervention, the risk is higher than average for patients with hemodynamic failure. Equally, should there be any postoperative improvement of cerebral blood flow or neurologic deficits, it should be looked for in this group. Thus, it is necessary to distinguish those with low perfusion pressure from the population of patients with carotid artery disease. Preoperative clinical evaluation and direct visualization of the carotid bifurcation should be supplemented by indirect physiological tests which allow assessment of collateral perfusion. Examination of periorbital flow direction or oculoplethysmography could be used as a screening procedure. Negative tests most certainly rule out any severe pressure gradient across the stenosis, irrespective of the luminal reduction. A positive result, on the other hand, should be further quantified since most indirect tests become positive at relatively small pressure gradients. Studies of cerebral blood flow at rest and during cerebral vasodilation makes it possible to identify patients with severe reduction of cerebral perfusion pressure. Such hemodynamic failure of one hemisphere may be identified in most cases by a conventional non-invasive xenon-133 technique and stationary detectors. Smaller focal regions of hypoperfusion may be identified by computer emission tomography, either by the detection of single-photon emission or by paired detection of annihilation photons. Endarterectomy does improve cerebral hemodynamics in terms of increased flow through the reconstructed vessel and elimination of pressure gradients. The cerebral blood flow, though remains unchanged in the majority of patients, at least when measured at baseline. Only in those patients with a reduction in perfusion pressure can a significant improvement in baseline flow occur. Flow reserve determined by cerebral vasodilation, however, will improve in most patients with hemodynamic failure. In addition, some patients in the low-pressure group develop marked, but temporary, hyperperfusion after reconstruction of very high grade carotid stenosis. This is considered a result of chronic low perfusion pressure with subsequent loss of autoregulation, and autoregulatory control is first regained after some days.(ABSTRACT TRUNCATED AT 400 WORDS)