电针百会、神庭对脑缺血再灌注损伤大鼠学习记忆能力及突触可塑性的影响

目的:探讨电针百会、神庭穴对脑缺血再灌注损伤大鼠学习记忆能力及突触可塑性的影响。方法:将36只清洁级雄性SD大鼠随机分为假手术组、模型组和电针组,其中12只仅分离血管作为假手术组,其余24只运用线栓法制备左侧大脑中动脉局灶性脑缺血再灌注大鼠模型,缺血时间为2 h。造模成功后采用随机数字表法分为模型组和电针组各12只。电针组大鼠给予电针百会、神庭穴,1次/d,持续7 d;其余2组同等条件抓取,不予干预。各组大鼠在造模成功后第3天开始采用Morris水迷宫检测大鼠学习记忆能力,水迷宫试验共持续5 d;采用透射电镜观察海马区突触超微结构的变化;免疫组化法检测突触后致密蛋白95(PSD-95)和突触囊泡膜蛋白-突触素(SYN)的表达。结果:水迷宫测试中,模型组与假手术组相比逃避潜伏期明显增加(P0.001),穿越平台次数减少(P0.01);电针组与模型组比较逃避潜伏期缩短(P0.01),穿越平台次数增加(P0.05),第5天的穿越平台轨迹较集中于平台附近,而模型组则较分散和不规则。通过透射电镜观察,模型组与假手术组相比突触数量显著减少(P0.001);电针组比模型组海马CA1区突触的结构更加清晰和完整,数量显著增加(P0.01)。免疫组化发现假手术组比模型组海马区PSD-95及SYN表达显著增高(P0.001);与模型组相比,电针组海马区的PSD-95表达明显增高(P0.001),SYN表达也显著增高(P0.01)。结论:电针百会、神庭穴可以改善脑缺血再灌注损伤大鼠学习记忆能力,其机制可能与增强突触可塑性,包括促进突触结构的完整,增加PSD-95和SYN的表达有关。     

重复经颅磁刺激对脑缺血大鼠海马突触素表达及学习记忆的影响

目的:观察10 Hz重复经颅磁刺激(r TMS)对脑缺血大鼠海马突触素(SYN)的表达及学习记忆的影响。方法:将36只雄性SD大鼠随机分成假手术组、模型组和r TMS组,每组12只。制备双侧颈总动脉永久结扎脑缺血模型,假手术组不造成缺血,r TMS组给予10 Hz r TMS,共28次。采用Morris水迷宫评价学习记忆能力;利用电生理实验检测海马CA1区的长时程增强(LTP);Western blot检测海马SYN蛋白的含量。结果:与假手术组比较,模型组的逃避潜伏期明显延长,60 s内跨越平台次数减少;与模型组比较,r TMS组大鼠的逃避潜伏期缩短,60 s内跨越平台次数增加,f EPSP波幅提高,海马SYN蛋白的表达增高,差异有统计学意义(P0.05)。结论:r TMS能促进脑缺血大鼠海马SYN蛋白的表达和增强高频刺激引起的LTP,这可能是r TMS改善脑缺血损伤引起的学习记忆障碍的作用机制之一。     

丰富环境干预对慢性低灌注血管性痴呆大鼠学习记忆及突触素蛋白和微管相关蛋白的影响

目的:观察丰富环境干预对慢性低灌注血管性痴呆大鼠学习记忆能力、海马突触素(SYN)蛋白及微管相关蛋白-2(MAP-2)表达的影响。方法:雄性SD大鼠随机分为正常对照组、模型组、丰富环境组。双侧颈总动脉永久性结扎制备慢性低灌注大鼠模型。丰富环境干预50d后,利用Morris水迷宫检测学习记忆功能;免疫组织化学法检测SYN、MAP-2的表达。结果:慢性低灌注大鼠空间参考记忆能力下降,搜索隐藏平台的逃避潜伏期和游泳路径明显延长;定位记忆障碍,在空间探索实验中准确穿越平台位置的次数减少;工作记忆明显损害,寻找移动平台的逃避潜伏期及游泳路径比正常大鼠明显延长(P0.01或P0.05)。海马CA1、CA3区SYN、MAP-2的免疫反应明显减弱(P0.01)。丰富环境干预后,大鼠搜索隐匿平台的逃避潜伏期和游泳路径均有不同程度的缩短,准确穿越平台所在位置的次数比模型组增加;移动平台位置后,动物找到平台的时间和游泳路径明显比模型组缩短(P0.01或P0.05);海马区SYN、MAP-2的积分光密度值均有不同程度增加(P0.01或P0.05)。结论:丰富环境干预可改善慢性低灌注大鼠学习记忆能力,其作用与上调海马SYN、MAP-2蛋白表达,提高突触可塑性有关。     

电针百会、神庭穴对脑缺血再灌注大鼠学习记忆能力及海马CA1区突触超微结构的影响

目的观察电针百会、神庭穴对脑缺血再灌注大鼠学习记忆能力及损伤大鼠海马CA1区突触超微结构的影响。方法雄性Sprague-Dawley大鼠25只随机分为假手术组(n=6)和手术组(n=19)。手术组线栓法建立左侧大脑中动脉栓塞90 min后再灌注模型,筛选符合纳入标准的12只大鼠随机分为模型组和电针组各6只。电针组电针百会、神庭穴7 d。采用Longa评分检测大鼠神经功能;小动物磁共振成像分析系统T2加权成像观察脑梗死体积;Barnes迷宫测试检测大鼠学习记忆能力;透射电镜观察海马CA1区突触超微结构。结果与模型组相比,电针组Longa评分降低(P0.05),脑梗死体积明显减少(P0.01);Barnes迷宫测试逃避潜伏期明显缩短(P0.01),平均进入错误洞口次数显著减少(P0.001)。透射电镜显示,模型组突触结构溶解,数量减少,囊泡稀疏、破坏;与模型组相比,电针组突触结构较清晰,突触数量较多,突触囊泡较多。结论电针百会、神庭能有效改善脑缺血再灌注大鼠的学习记忆能力,其机制可能与改善海马CA1区突触的超微结构,提高突触可塑性有关。     

电针百会、神庭穴对缺血再灌注损伤大鼠学习记忆能力及海马CA1区嘌呤受体P2X7表达的影响

目的观察电针百会、神庭穴对缺血再灌注损伤大鼠学习记忆功能的影响,并探究其可能机制。方法雄性Sprague-Dawley大鼠42只随机分为假手术组(n=12)和手术组(n=30)。手术组线栓法制备左侧大脑中动脉栓塞90 min再灌注模型,符合纳入标准的24只分为模型组(n=12)和电针组(n=12)。电针组电针百会、神庭共7 d。造模后2 h和干预后1 d、3 d、7 d,采用Longa神经行为学评分进行评定;干预后3 d起行Barnes迷宫实验检测,共5 d;干预7 d后,免疫荧光标记法检测缺血侧海马CA1区嘌呤受体P2X7的表达,酶联免疫吸附法检测海马CA1区白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)。结果干预后7 d,与模型组相比,电针组Longa评分降低(P0.05);与假手术组相比,模型组Barnes迷宫逃避潜伏期显著延长(P0.001),进入错误洞口次数显著增多(P0.001);与模型组相比,电针组逃避潜伏期显著缩短(P0.001),进入错误洞口次数显著减少(P0.001);与假手术组比较,模型组P2X7受体平均光密度,IL-1β、TNF-α水平均显著提高(P0.001);与模型组相比,电针组P2X7受体表达,IL-1β、TNF-α水平减少(P0.05)。结论电针百会、神庭穴能有效改善缺血再灌注损伤大鼠的学习记忆能力,可能与抑制海马CA1区嘌呤受体P2X7表达,改善缺血再灌注损伤大鼠海马CA1区神经炎症反应有关。     

脑伤泰对血管性痴呆大鼠学习记忆的影响

目的观察血管性痴呆(VD)大鼠P300与海马突触素(synaptophysin,SYN)改变及脑伤泰对其的影响。方法采用Pulsinlli-4血管法制作VD大鼠模型,分为假手术组、模型组、治疗组,测定P300潜伏期,免疫组化法行海马突触素染色并进行分析。结果治疗组P300延长,海马SYN光密度值明显下降,但在术后8周P300缩短,海马SYN光密度值明显上升。结论脑伤泰缩短P300潜伏期,改善VD大鼠学习记忆能力,其机制可能与提高海马SYN水平有关。     

电针百会、大椎、肾俞穴对SAMP8小鼠学习记忆与海马CA1区神经元突触的影响

目的观察电针百会、大椎、肾俞穴对SAMP8小鼠学习记忆与海马CA1区神经元突触的影响,探讨电针治疗阿尔茨海默病(AD)的机制。方法 7月龄SAMP8小鼠24只随机分为模型组和电针组,同龄正常老化SAMR1小鼠12只为对照组。电针组电针百会、大椎、肾俞穴30 d。Morris水迷宫检测小鼠学习记忆能力,免疫组织化学观察小鼠海马CA1区突触素(SYN)及突触后致密区蛋白95(PSD95)的表达,透射电镜观察小鼠海马CA1区突触超微结构的变化。结果与模型组相比,电针组逃避潜伏期缩短(P0.05),原平台象限停留时间延长(P0.05),穿越原平台次数增加(P0.05),海马CA1区SYN与PSD95表达显著提高(P0.001),突触结构较完整,数量增加。结论电针能提高小鼠海马CA1区神经元突触蛋白的表达,改善突触的超微结构,从而有效改善SAMP8小鼠的学习记忆能力。     

艾地苯醌改善血管性痴呆大鼠认知功能及其对海马区生长相关蛋白-43和突触素P38表达的影响

目的:探讨艾地苯醌对血管性痴呆(VD)大鼠认知功能的作用,并初步探讨其机制。方法:SD大鼠60只随机均分为3组:假手术组、模型组和艾地苯醌组,各20只。采用改良双血管阻断(2-VO)法建立大鼠VD模型,艾地苯醌组大鼠腹腔注射艾地苯醌,10 mg/kg,1次/d,连续给药30 d;模型组及假手术组腹腔注射等量生理盐水。采用水迷宫评价各组大鼠学习、记忆能力;免疫组化测定海马生长相关蛋白-43(GAP-43)、突触素P38表达;透射电镜观察突触超微结构的改变。结果:模型组逃避潜伏期长于假手术组和艾地苯醌组(P<0.05),穿越原平台次数少于假手术组和艾地苯醌组(P<0.05);艾地苯醌组逃避潜伏期和穿越原平台次数与假手术组差异无统计学意义(P>0.05)。模型组GAP-43和触素P38蛋白的表达水平均低于其他2组(P<0.05);艾地苯醌组GAP-43和触素P38蛋白的表达水平均高于其他2组(P<0.05)。电镜下可见模型组大鼠海马区突触结构受损,艾地苯醌组大鼠海马组织区突触数量丰富,结构基本完整。结论:艾地苯醌可改善VD大鼠的学习和记忆功能,其机制可能与增强突触相关蛋白GAP-43和突触素P38的表达有关。     

脑伤泰对血管性痴呆大鼠学习记忆的影响

目的 观察血管性痴呆（VD）大鼠P300与海马突触素（synaptophysin,SYN）改变及脑伤泰对其的影响。方法 采用Pulsinlli-4血管法制作VD大鼠模型，分为假手术组，模型组，治疗组，测定P300潜伏期，免疫组化法行海马突触素染色并进行分析。结果 治疗组P300延长，海马SYN光密度值明显下降，但在术后8周P300缩短，海马SYN光密度值明显上升。结论 脑伤泰缩短P300潜伏期，改善VD大鼠学习记忆能力，其机制可能与提高海马SYN水平有关。     

灵芝三萜对癫痫大鼠学习记忆损伤的效果

目的 研究灵芝三萜对戊四氮致痫大鼠认知功能的影响及其作用机制。方法 75只Sprague-Dawley大鼠随机分为空白对照组、癫痫模型组、灵芝三萜组、外源性单唾液酸四己糖神经节苷脂(GM1)组和灵芝三萜联合GM1组,每组15只。除空白对照组外,其余各组用戊四氮35 mg/kg腹腔注射,每天1次,持续28 d。各用药组在每天腹腔注射戊四氮的同时进行相应给药。造模后,行Morris水迷宫测试;HE染色及透射电镜观察海马神经元;实时定量聚合酶链反应检测大鼠海马肌动蛋白结合蛋白(Cofilin)、突触素(SYN)、神经生长相关蛋白43 (GAP-43)的mRNA表达水平。结果 与空白对照组比较,各时间点癫痫模型组逃避潜伏期延长(P < 0.05);与癫痫模型组比较,各用药组逃避潜伏期均缩短,部分时间点有显著性差异( P < 0.05)。与癫痫模型组比较,各用药组穿越平台次数明显增多( P < 0.01),在目标象限停留时间明显延长( P < 0.01)。各用药组海马神经元数增加,核溶解碎裂减少,核膜结构较清楚,突触小泡增多,突触数量增加,细胞器结构有所改善。与空白对照组相比,癫痫模型组Cofilin mRNA水平上调( P < 0.05),SYN mRNA和GAP-43 mRNA水平降低( P < 0.05);与癫痫模型组比较,各用药组Cofilin mRNA表达水平降低( P < 0.05),SYN mRNA表达水平升高( P < 0.05),仅灵芝三萜联合GM1组GAP-43 mRNA升高( P < 0.05)。 结论 灵芝三萜和GM1及两者联合用药均可改善癫痫大鼠的学习记忆能力及神经元形态结构,其机制可能与影响海马突触生长重塑相关基因表达有关,以达到保护大脑神经元的作用。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.