缺氧对乳鼠心肌细胞凋亡的诱导作用

目的　观察缺氧对心肌细胞凋亡的诱导作用。方法　体外培养的Wistar乳鼠心肌细胞分别缺氧 2小时、1 2小时、2 4小时 ,采用流式细胞术、TdT介导的dUTP末端标记法 (TUNEL)以及形态学方法检测心肌细胞凋亡。结果　各缺氧组心肌细胞凋亡数量均显著高于对照组 ,随着缺氧时间延长凋亡细胞数量逐渐增加 ,对照组、缺氧 2小时、1 2小时、2 4小时组凋亡细胞数量分别为 9 3 3± 0 62 % ,1 7 2 9± 0 95% ,3 3 59± 2 0 9% ,76 0 1± 4 60 % (P <0 0 1 )。缺氧 2 4小时心肌细胞TUNEL染色阳性 ,HE染色及透射电镜观察心肌细胞表现出凋亡的形态特征。结论　缺氧可以诱导乳鼠心肌细胞凋亡。     

OPA1在缺氧心肌细胞凋亡中的保护作用

目的：探讨线粒体融合蛋白OPA1在缺氧环境下心肌细胞凋亡中的保护作用。方法：利用小干扰RNA(siRNA)在体外下调OPA1表达后,用流式检测对缺氧环境下心肌细胞凋亡的影响;用Western blot检测对缺氧环境下心肌细胞线粒体细胞色素c释放及Caspase-3与Caspase-9活性的影响;用流式分析对缺氧环境下心肌细胞活性氧ROS产生的影响。结果：下调OPA1可明显加重缺氧诱导的心肌细胞凋亡;下调OPA1可诱导线粒体细胞色素c释放并同时激活Caspase-3与Caspase-9的活性;下调OPA1可诱导心肌细胞中ROS产生。     

生长阻滞和DNA损伤诱导基因153在慢性缺氧诱导心肌细胞凋亡中的表达

目的研究慢性缺氧诱导心肌细胞发生凋亡的情况,探讨生长阻滞和DNA损伤诱导基因(CHOP/GADD153)蛋白表达变化与心肌细胞凋亡的关系。方法将体外培养的心肌细胞置于95%N_2/5%CO_2混合气体培养箱内进行慢性缺氧处理,随机将心肌细胞分为对照组及缺氧6、12、24、48、72 h组。采用流式细胞术及DNA梯度技术检测心肌细胞凋亡情况.RT-PCR检测CHOP/GAD153 mRNA水平变化,western blot检测细胞凋亡过程中CHOP/GADD153蛋白表达变化。结果缺氧6 h组心肌细胞出现典型的凋亡特征;与对照组比较,缺氧12、24、48、72 h组心肌细胞凋亡数量明显增多(P<0.05):CHOP/GADD153 mRNA和蛋白表达水平也明显增加(P<0.05)。结论慢性缺氧可诱导心肌细胞发生凋亡,CHOP/GADD153可能参与了慢性缺氧诱导心肌细胞凋亡的信号传导通路。     

X染色体连锁凋亡抑制蛋白对缺氧-复氧诱导的新生大鼠心肌细胞凋亡的影响

目的:采用X染色体连锁凋亡抑制蛋白(XIAP)对缺氧-复氧诱导心肌细胞凋亡模型进行干预,以探讨脂质体介导XIAP基因转染对缺氧-复氧诱导的新生大鼠心肌细胞凋亡的影响.方法:体外培养新生大鼠心肌细胞,分为4组,①XIAP组:将pDsRed2-XIAP以脂质体转染到心肌细胞48 h后进行缺氧2 h-复氧1 h;②预处理组:先将心肌细胞进行缺氧预处理,然后进行缺氧2 h-复氧1 h;③单纯缺氧-复氧组:将心肌细胞直接进行缺氧2 h-复氧1 h;④常氧组:将心肌细胞在CO2孵箱中培养3 h.各组最后用流式细胞仪Annexin V FITC检测心肌细胞凋亡率结果组间差异.结果:①pDsRed2- XIAP可以通过脂质体转染的方式转染到心肌细胞;②与单纯缺氧-复氧组比较,XIAP组和预处理组心肌细胞凋亡率明显减低,P<0.01;③XIAP组与预处理组比较二者心肌细胞凋亡率相似,P>0.05.结论:以物理性的缺氧2 h-复氧1 h的方式能诱导所培养的心肌细胞发生凋亡;XIAP能明显减少缺氧-复氧诱导新生大鼠心肌细胞的凋亡;XIAP抑制凋亡的效应与缺氧预处理抑制凋亡的效应相似.     

缺氧与缺氧/复氧诱导心肌细胞凋亡的比较及意义

目的 :研究单纯缺氧与缺氧复氧对体外培养的新生大鼠心肌细胞凋亡的影响 ,探讨凋亡在心肌细胞缺氧 /复氧损伤中的作用。方法 :取体外培养的新生大鼠心肌细胞 ,分两组 ,均置于 95 0 ml/ L N2 ,5 0 ml/ L CO2 孵箱中培养16 ,32 ,4 8h,其中一组缺氧后再恢复正常条件培养 6 h,分别造成缺氧和缺氧 /复氧损伤的细胞模型 ,TUNEL 染色观察凋亡细胞形态学变化 ,流式细胞仪检测心肌细胞凋亡率。结果 :心肌细胞经历缺氧和缺氧 /复氧损伤后 ,TU NEL 染色可见凋亡阳性细胞 ;应用流式细胞仪定量检测 ,心肌细胞缺氧培养 16 ,32 ,4 8h后 ,其凋亡率分别为 :（2 .9± 0 .5 ） % ,（6 .2± 0 .8） %和 （2 6 .6± 3.0 ） % ;心肌细胞在缺氧 16 ,32和 4 8h后复氧 6 h,其凋亡率分别为 :（5 .5± 0 .7） % ,（11.0± 1.1） %和 （14 .2± 1.6 ） %。结论 :心肌细胞凋亡率随着缺氧时间的延长而增高 ;缺氧 /复氧较单纯缺氧可进一步加重心肌细胞的损伤     

热诱导延迟损伤大鼠心肌细胞凋亡机理的探讨

目的探讨热诱导延迟过氧化氢(H2O2)造成大鼠心肌细胞凋亡机理。方法体外培养大鼠乳鼠心肌细胞同时温度诱导细胞产生热休克蛋白70(HSP70)，用H2O2造成心肌细胞损伤。采用Western Blottmg、流式细胞仪、Bcl-2原位杂交、免疫组化检测Caspase-3等作为检测指标，观察心肌细胞损伤，以及HSP70对心肌细胞的保护作用。结果温度诱导后HSP70在胞浆中大量表达，保护组凋亡率显著低于损伤组，Bcl-2和Caspase-3在损伤组大量表达。结论HSP70可延迟细胞凋亡，对心肌细胞具有保护作用。     

视神经萎缩相关蛋白A1在缺氧心肌细胞凋亡中的抑制作用

目的:探讨视神经萎缩相关蛋白A1(OPA1)在缺氧心肌细胞凋亡中的保护作用。方法:利用小干扰RNA(siRNA)在体外下调OPA1表达后,采用流式检测下调OPA1对缺氧心肌细胞凋亡的影响;用Western blot检测下调OPA1对缺氧心肌细胞线粒体细胞色素C释放及含半胱氨酸的天冬氨酸蛋白水解酶Caspase-3与Caspase-9活性的影响;用流式分析下调OPA1对缺氧心肌细胞活性氧(ROS)产生的影响。结果:下调OPA1可明显加重缺氧诱导的心肌细胞凋亡,诱导线粒体细胞色素C释放并激活Caspase-3与Caspase-9活性,诱导心肌细胞中ROS产生。结论:OPA1分子具有抑制缺氧心肌细胞凋亡的作用,其机制可能是OPA1介导的线粒体融合抑制了线粒体中细胞色素C的释放与ROS的生成。     

悬浮培养诱导人胚胎干细胞分化为心肌细胞的研究

目的:利用不加任何诱导剂的悬浮培养法,体外诱导人胚胎干细胞分化为心肌细胞并检测其分化效率。方法:人胚胎干细胞克隆用200U/mL胶原酶Ⅳ,370C处理10min后,挑起克隆碎片转移到低黏附性培养皿中悬浮培养以形成EB(拟胚体),4d后将EB转移到基质胶处理过的6孔板中贴壁培养(1-3EBs/cm2),显微镜下观察记录出现跳动心肌细胞的时间和跳动频率,并计算跳动克隆百分比,24孔板一组,共记录4组96孔;免疫荧光染色检测心肌细胞特异标志物cTnT;膜片钳实验检测心肌细胞自发性动作电位;跳动心肌细胞经过24h缺氧刺激后,用凋亡试剂盒检测心肌细胞凋亡比例。结果:在悬浮培养14d左右开始出现大量的自发跳动心肌细胞,分化出现自发跳动心肌细胞的平均时间(13.9±0.9)d,百分比为20.8%,平均跳动频率为(63.8±5.6)次/min;跳动心肌细胞cTnT染色阳性;跳动心肌细胞检测到自发性动作电位;跳动心肌细胞缺氧24h的凋亡比例为(8.1±0.4)%。结论:不加诱导剂的悬浮培养可以诱导人胚胎干细胞分化为心肌细胞,分化效率达到20.8%,分化时间14d左右。为进一步的干细胞移植治疗动物心肌梗死模型提供种子细胞。     

细胞组学技术在心肌细胞凋亡研究中的应用

目的：利用高内涵筛选（high-content screening,HCS）、流式细胞术（flow cytometry,FCM）、激光扫描细胞分析术（laser scanning cytometry,LSC）等细胞组学技术对心肌细胞凋亡特征进行研究.方法：缺氧缓冲液处理H9C2心肌细胞,建立体外心肌细胞凋亡模型,以常规DMEM培养为对照组,处理6h后收取细胞行Annexin V-FITC、PI染色,分别利用HCS和FCM检测,分析心肌细胞早、晚期凋亡以及坏死的比例.利用小鼠心脏左前降支结扎,建立心肌梗死在体模型,术后28d收取心脏,进行TUNEL染色,利用HCS和LSC分析心脏组织健存区、交界区和梗死区心肌细胞的凋亡.结果：缺氧缓冲液处理H9C2心肌细胞6h后,HCS和FCM方法均显示早期凋亡细胞缺氧组与DMEM组,差异有统计学意义,分别为[（17.69±2.85）vs.（5.31±0.86）％,P＜0.01]和[（12.18±0.61）vs.（3.08±0.15）％,P＜0.01],晚期凋亡与坏死细胞比例变化不明显,表明缺氧缓冲液处理6h主要诱导心肌细胞早期凋亡.小鼠心肌梗死28d后,HCS和LSC方法均显示心脏梗死区和交界区有凋亡细胞,梗死区更明显,整体凋亡率分别为6.08％和4.35％,健存区无细胞凋亡.结论：HCS和FCM方法能够可靠、稳定和量化评价心肌细胞凋亡,准确区分细胞早、晚期凋亡和坏死,两种方法结果一致;HCS和LSC方法还可分析组织水平的细胞凋亡;而LSC优势在于可明确凋亡细胞的组织定位.     

基于Caspase-3基因的RNA干扰对缺氧诱导的心肌细胞凋亡的影响

目的 研究RNA干扰Caspase-3基因表达对缺氧诱导的心肌细胞凋亡的影响,探讨Caspase-3基因表达的RNA干扰方法在缺氧诱导的心肌细胞凋亡中的作用与机制.方法 以基于Caspase-3基因的small interferenceRNA(siRNA)处理缺氧诱导的心肌细胞,不同时期分别检测心肌细胞凋亡率、乳酸脱氢酶(LDH)漏出、钙浓度、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性的变化,以逆转录聚合酶链反应(RT-PCR)和Western-blot法分别检测Caspase-3基因表达水平和蛋白表达水平.结果 缺氧诱导心肌细胞后,心肌细胞、凋亡率随时间进程明显增加.缺氧诱导使心肌细胞LDH漏出、钙浓度、MDA含量增加而SOD活性降低.缺氧诱导下RNA干扰组心肌细胞Caspase-3基因mRNA转录水平、蛋白表达水平和心肌细胞凋亡率较空白对照组和错义RNA干扰组差异有统计学意义(P<0.05).结论 基于Caspase-3基因的RNA干扰显著抑制缺氧诱导的心肌细胞凋亡率,提示Caspase-3基因表达在缺氧诱导的心肌细胞凋亡中具有重要的作用.     

胰岛素瘤的解剖分布特点分析

目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤，因其临床表现多样，导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用，拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点，以期有助于提高影像学的诊断准确率和降低漏诊率，尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料，检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例，通过查阅病例的方法，提取出胰岛素瘤的大小和解剖分布等数据，进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例，其中，男45例、女71例，年龄13～76岁，平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布：头颈部46例(39.7%)，单发45例、多发1例；体尾部68例(58.6%)，单发65例、多发3例；全胰腺多发2例(1.7%)。病变大小特点：最大径0.4～3.4 cm，平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例，≤3 cm 15例，>3 cm 3例。年龄与肿瘤的大小相关，≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm，P<0.05。头颈部的肿瘤大于体尾部的肿瘤，头颈部肿瘤平均大小(1.66±0.63)cm，体尾部(1.42±0.52)cm，P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发；绝大多数单发，但可以全胰腺多发；多数小于1.5 cm，肿瘤的大小与患者年龄和肿瘤的解剖分布相关。     

Pathogenesis of carcinoma of the papilla of Vater

Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.     

Demonstration of the mechanism of action of biguanides

Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.     

Lack of correlation of degree of villous atrophy with severity of clinical presentation of coeliac disease

BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.     

血吸虫童虫生长发育及其机制的研究进展

血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。     

氯硝柳胺悬浮剂的毒性评价

目的评价氯硝柳胺悬浮剂的毒性，为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg，经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3，该药经口、经皮肤、经呼吸道毒性均属微毒类药物；兔眼用药后，观察期内无不良反应，对眼无刺激性；皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比，氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物，对鱼的毒性低于其乙醇胺盐可湿性粉剂，适合于现场应用。     

124例耐多药结核分枝杆菌基因突变特征分析

目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。     

Assessment of quality of life of parents of children with juvenile chronic arthritis

The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002     

Numerical Simulation of the Effect of Rate of Change of Glucose on Measurement Error of Continuous Glucose Monitors

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl⁻¹•min⁻¹ (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl⁻¹•min⁻¹ (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.     

治疗高血压药物的经济学评价

重视高血压治疗中的经济学评价,对利用我国有限的卫生资源来遏制高血压对人民群众的危害有着重要的现实意义。药物经济学对于药物治疗的成本和治疗的结果给予同样的关注。因为治疗高血压的费用,不仅涉及药物价格,还包括患者的危险水平,降压疗效和对临床终点事件的影响,以及治疗的依从性和安全性。因此药物经济学更强调整体成本和价-效比。低危病人,若非药价低廉,治疗的价-效比不够理想。而在高危的患者,价-效比越小越经济而不是药费越便宜越好。