GDNF基因诱导骨髓间充质干细胞向神经细胞分化的实验研究

目的 观察在体外培养的经GDNF基因诱导的骨髓间充质干细胞（BMSCs）向神经细胞分化的表达.方法 体外培养大鼠骨髓间充质干细胞,选取第3代细胞,应用GDNF基因诱导BMSCs分化两周,观察诱导后细胞的形态学变化,免疫荧光方法验证及鉴定神经元特异性烯醇化酶（NSE）及髓磷脂酸性蛋白2（MAP-2）的表达.结果 镜下观察细胞形态学以及特异性荧光可见BMSCs向神经细胞分化明显.结论 GDNF基因转染的BMSCs在体外培养情况下可转化为神经细胞,并表达特定神经细胞标志蛋白.     

视网膜干细胞培养上清液诱导骨髓间充质干细胞的分化

背景：骨髓间充质干细胞向神经细胞诱导分化可为神经系统受损伤后的修复和再生带来了新的希望。
　　目的：探讨骨髓间充质干细胞在视网膜干细胞培养上清液诱导条件下向神经元细胞分化。
　　方法：采用全骨髓培养方法,用视网膜干细胞培养上清液诱导骨髓间充质干细胞,通过免疫荧光染色鉴定其分化的结果。
　　结果与结论：诱导72 h,骨髓间充质干细胞表达神经干细胞的特异性抗体巢蛋白和神经元中的标志性微管相关蛋白微管相关蛋白2。视网膜干细胞培养上清液能够促进骨髓间充质干细胞向神经元样细胞分化,提示视网膜干细胞可能分泌神经生长因子。     

环氧化酶2基因沉默不影响人骨髓间充质干细胞定向分化的能力

背景：目前环氧化酶2基因沉默在干细胞中的研究还处在初级阶段。目的：构建携带环氧化酶2基因沉默的慢病毒载体,观察其在人骨髓间充质干细胞中的表达,以及其定向分化潜能变化情况。方法：应用重组慢病毒技术构建携带沉默环氧化酶2基因和绿色荧光蛋白的慢病毒载体,并用其转染体外培养第3代的人骨髓问充质干细胞,以无目的基因的慢病毒转染人骨髓间充质干细胞的实验组和未做处理的人骨髓间充质干细胞分别作为阴性对照组和空白组进行对比。转染后7d分别提取各组细胞的总RNA和蛋白检测环氧化酶2表达量。对环氧化酶2基因沉默的人骨髓间充质干细胞和正常人骨髓间充质干细胞定向诱导,观察环氧化酶2基因沉默对人骨髓间充质干细胞成脂、成骨、成软骨能力的影响。结果与结论：慢病毒转染3d后,荧光显微镜下可见人骨髓间充质干细胞发出绿色荧光,阴性对照组转染效率可达90％以上,实验组转染效率达85％以上。F盯．PCR和Westernblot检测结果显示,环氧化酶2基因在人骨髓间充质干细胞中的基因水平和蛋白水平均得到了明显抑制。环氧化酶2基因转染对人骨髓间充质干细胞成脂、成骨、成软骨能力无明显影响。     

转化生长因子β3基因转染兔骨髓间充质干细胞诱导其向软骨表型的分化

背景：内源性诱导软骨分为就是通过一定的载体将目的基因整合入干细胞内,使其自行分泌诱导因子诱导自身进行分化。目的：观察将转化生长因子β3通过腺相关病毒载体转染诱导兔骨髓间充质干细胞向软骨表型转化的能力。方法：取体外培养的第3代骨髓间充质干细胞进行重组腺相关病毒转染,将转染后3,6,9,12d细胞裂解提取蛋白进行酶联免疫检测目的蛋白转化生长因子β3的体外表达。RT-PCR,免疫印迹westernblot分别从基因和蛋白水平上检测1,2周Ⅱ型胶原的表达,甲苯胺蓝染色检测1,2周蛋白多糖的表达。结果与结论：重组腺相关病毒转染后,骨髓间充质干细胞可以较稳定的表达目的蛋白转化生长因子β3,并且转染成功的骨髓间充质干细胞较阴性对照组能够更好的向软骨表型转化。证实转化生长因子β3可以腺相关病毒为载体转染骨髓间充质干细胞并诱导其向软骨表型分化。     

转化生长因子β3基因转染兔骨髓间充质干细胞诱导其向软骨表型的分化

背景:内源性诱导软骨分为就是通过一定的载体将目的基因整合入干细胞内,使其自行分泌诱导因子诱导自身进行分化.目的:观察将转化生长因子β3 通过腺相关病毒载体转染诱导兔骨髓间充质干细胞向软骨表型转化的能力.方法:取体外培养的第3 代骨髓间充质干细胞进行重组腺相关病毒转染,将转染后3,6,9,12 d 细胞裂解提取蛋白进行酶联免疫检测目的蛋白转化生长因子β3 的体外表达.RT-PCR,免疫印迹western blot 分别从基因和蛋白水平上检测1,2 周Ⅱ型胶原的表达,甲苯胺蓝染色检测1,2 周蛋白多糖的表达.结果与结论:重组腺相关病毒转染后,骨髓间充质干细胞可以较稳定的表达目的蛋白转化生长因子β3,并且转染成功的骨髓间充质干细胞较阴性对照组能够更好的向软骨表型转化.证实转化生长因子β3 可以腺相关病毒为载体转染骨髓间充质干细胞并诱导其向软骨表型分化.     

虫草多糖体外诱导大鼠骨髓间充质干细胞分化为类肝细胞样细胞☆

背景:如何促进骨髓间充质干细胞向肝细胞完全意义上的转化,以便更有效改善病变肝组织的结构和功能将成为未来相关研究的重中之重。目的:探讨虫草多糖在体外诱导大鼠骨髓间充质干细胞分化为类肝细胞样细胞的可行性。方法:采用贴壁法培养Wistar大鼠骨髓间充质干细胞,实验分3组对骨髓间充质干细胞进行诱导分化,虫草组培养液中加虫草多糖进行诱导,终末质量浓度为0.15g/L;阳性对照组培养液中加肝细胞生长因子和表皮生长因子联合诱导,质量浓度分别为20μg/L和10μg/L;空白对照组仅用含体积分数为10%胎牛血清的DMEM培养液。结果与结论:分离纯化的骨髓间充质干细胞经流式细胞仪检测显示CD34阴性表达,CD44阳性表达。诱导分化7d时虫草组及阳性对照组细胞出现甲胎蛋白表达,14d时表达增强,28d时表达减弱,阳性对照组甲胎蛋白阳性率高于虫草组;诱导分化7d时阳性对照组细胞角蛋白18出现表达,14d时表达增强,虫草组则在14d时出现表达,而后持续。诱导分化7d时虫草组及阳性对照组白蛋白表达阴性,14d时出现阳性。诱导分化14d时虫草组及阳性对照组细胞糖原染色阳性,28d时表达减弱。空白对照组结果皆为阴性。结果可见虫草多糖可以在体外诱导大鼠骨髓间充质干细胞分化为类肝细胞样细胞。     

携带CXCR4基因慢病毒载体转染大鼠骨髓间充质干细胞的体外实验

背景：间充质干细胞在体内归巢主要调控因子是CXCR4,如何提高干细胞自身CXCR4的表达量是调节干细胞体内靶器官归巢能力的关键。
　　目的：构建CXCR4或GFP基因慢病毒表达载体,并观察其对骨髓间充质干细胞自身生长特性及分泌功能的影响。
　　方法：骨髓间充质干细胞应用慢病毒载体转染系统转染CXCR4基因达到过表达,同时单独转GFP基因作为对照。通过荧光显微镜、RT-PCR、免疫蛋白印迹方法验证病毒转染效率;流式细胞技术测定骨髓间充质干细胞的增殖、凋亡情况;Western Blot法测定间充质干细胞培养基上清中分泌蛋白及细胞因子变化。
　　结果与结论：慢病毒转染系统可以安全、有效地转染CXCR4基因或GFP基因到骨髓间充质干细胞。流式细胞仪检测显示过表达CXCR4的骨髓间充质干细胞增殖能力、生存能力加强,凋亡细胞减少(P<0.05);细胞上清蛋白分析提示过表达CXCR4后,骨髓间充质干细胞培养上清内出现很多的蛋白因子升高(P<0.05),其中大多数对细胞自身复制及免疫调节有益。结果表明慢病毒转染是一种安全高效的基因修饰手段,可以通过CXCR4基因修饰的方法提高骨髓间充质干细胞的生存能力、降低凋亡率,调节细胞保护性因子及免疫调节因子的分泌功能。     

体外诱导大鼠骨髓间充质干细胞向神经元样细胞的分化(英文)

背景:研究表明,移植后的骨髓间充质干细胞在新的环境中能够被诱导分化为神经元样细胞,从而替代损伤细胞重建神经环路。目的:建立大鼠骨髓间充质干细胞和神经细胞的体外共培养系统,观察共培养条件下神经细胞对骨髓间充质干细胞向神经元样细胞分化的影响。方法:体外培养Wistar大鼠脑组织神经细胞和股骨骨髓间充质干细胞,采用Transwell小室共培养分化诱导,观察骨髓间充质干细胞的组织形态变化,在共培养第5天免疫荧光染色检测骨髓间充质干细胞中神经细胞的特异标志物;与对照组单纯骨髓间充质干细胞培养结果相比较。结果与结论:神经细胞共培养系统中的骨髓间充质干细胞生长伸展,呈放射状,互相形成连接,特异性烯醇化酶显示阳性结果,具有神经元样细胞的特性,表达特异性烯醇化酶阳性的神经元比例可达(33.0±10.5)%。而对照组骨髓间充质干细胞未形成神经元样细胞的形态结构,免疫荧光显示特异性烯醇化酶阴性。提示神经细胞提供的微环境对骨髓间充质干细胞分化为神经元样细胞具有诱导分化作用。     

稳定转染增强型绿色荧光蛋白大鼠骨髓间充质干细胞系的建立

背景：利用间充质干细胞或含有治疗因子的干细胞进行有选择性的杀伤肿瘤细胞是一种有前途的治疗方法。目的：建立含稳定转染增强型绿色荧光蛋白的大鼠骨髓间充质干细胞系。方法：通过脂质体介导慢病毒质粒pVector-EGFP、pHelper、Envelope共转染293T细胞完成载体病毒构建,以实时荧光定量PCR检测慢病毒滴度;取对数生长期的SD大鼠骨髓间充质干细胞,以复感染指数MOI值0,5,10,15,20加入携带报告基因增强型绿色荧光蛋白的慢病毒载体稀释液,72h后观察各组增强型绿色荧光蛋白的表达效率及阳性转染率。结果与结论：携带增强型绿色荧光蛋白的慢病毒载体系统转染293T细胞能够正确表达,滴度为1×108TU/mL。包装好的病毒颗粒转染大鼠骨髓间充质干细胞二三天后,各孔均有增强型绿色荧光蛋白的表达。MOI值从0增至10,细胞的阳性表达率逐渐提高（P〈0.05）,MOI值为10的组能获得〉70%的转染率,但MOI值从10增至20,转染率变化不明显。说明以MOI值为10的滴度将慢病毒载体可将外源基因高效转入大鼠骨髓间充质干细胞内,建立含稳定转染增强型绿色荧光蛋白的大鼠骨髓间充质干细胞系。     

骨髓间充质干细胞向甲状腺细胞的分化

背景：特定环境下体外可定向诱导大鼠骨髓间充质干细胞向甲状腺细胞分化。目的：建立大鼠骨髓间充质干细胞体外诱导为甲状腺细胞的实验方法。方法：采用密度梯度法分离培养大鼠骨髓间充质干细胞,应用促甲状腺素和胰岛素诱导,以未诱导组为平行对照。利用倒置光学显微镜、透射电镜观察细胞分化过程的形态学变化,免疫荧光等检测方法研究成人骨髓间充质干细胞的分化情况。结果与结论：诱导培养第7天可见分化细胞中有甲状腺细胞的特有基因如TSHr的表达,第9天检测到分化细胞中甲状腺细胞标记物TTF-1的表达;对照组未见变化。形态学与生物学证实了骨髓间充质干细胞可诱导培养为甲状腺细胞。     

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.     

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.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.     

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.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.