急性心肌梗死后1周兔心室肌细胞钠离子通道活性的变化

目的:研究急性心肌梗死(AMI)后心室肌细胞钠离子通道活性的变化。方法:采用结扎兔冠状动脉左前降支方法建立AMI动物模型, 应用膜片钳全细胞记录方法, 观察AMI后1周心外膜梗死区心肌细胞钠通道电流(I_Na)的变化。结果:正常对照组I_Na电流密度峰值(-30mV)为(45.5±5.33)PA/PF(n=12), 心梗组为(22.48±4.62)PA/PF(n=14), 明显低于对照组, P＜0.01, I_Na电流-电压关系曲线在心梗组明显下移;心梗组I_Na失活曲线较对照组明显左移, 对照组V_0.5为(-76.2±5.3)mV(n=5), 心梗组为(-89.1±5.6)mV(n=6), P＜0.05;心梗组钠通道灭活后恢复时程明显慢于对照组, 恢复曲线下移。结论:AMI可导致梗死区心室肌细胞I_Na下降、钠通道动力学发生变化, 引起心肌传导速度下降和不应性延长, 可能是导致AMI后出现折返性室性心律失常的原因。     

卡巴胆碱抑制肿瘤坏死因子所致微血管内皮细胞通透性增高

目的探讨卡巴胆碱对肿瘤坏死因子-α（tumor necrosis factor-α，TNF-α）诱导的增加微血管通透性的作用。方法采用FITC标记白蛋白漏出法、考马斯亮蓝染色法观察卡巴胆碱对TNF-α诱导微血管内皮细胞通透性，细胞形态和细胞骨架变化的影响。结果与对照组比较，TNF-α明显增加微血管内皮细胞通透性（P〈0．05），诱导细胞皱缩，细胞间隙增大和细胞骨架排列紊乱。给予卡巴胆碱可以明显抑制TNF-α诱导微血管内皮细胞通透性增加，并呈剂量依赖性，同时可以使细胞间隙明显减小，细胞骨架排列有序。结论卡巴胆碱可能通过抑制TNF-α对细胞骨架的损伤，进而抑制微血管通透性增加。     

抗汉坦病毒单克隆抗体F（ab‘）2的制备及其纯度和活性鉴定

利用木瓜蛋白酶分别制备了抗汉坦病毒鼠源性单克隆抗体（ｍＡｂ）３Ｇ１和３Ｄ８Ｆ（ａｂ′）２片段。通过ＷａｔｅｒＤＥＡＥ４０ＨＲ阴离子交换色谱柱纯化后，非还原型ＳＤＳＰＡＧＥ呈现单一条带，相对分子质量（Ｍｒ）约１０００００。两种Ｆ（ａｂ′）２片段均具有良好的血凝抑制活性、病毒中和活性及对汉坦病毒感染乳鼠的保护作用     

肽抗生素hPAB-β在毕赤酵母中的表达与活性鉴定

目的 构建表达人源肽抗生素hPAB-β的重组毕赤酵母,为大量制备hPAB-β奠定基础.方法 用PCR及引物延伸法得到天然及优化的hPAB-β序列,克隆入pPIC9K质粒,转化DH5α大肠埃希菌,用酶切和核苷酸测序鉴定.重组质粒经SalⅠ酶线性化,整合入毕赤酵母GS115中,在DNA,mRNA及蛋白水平鉴定阳性重组子.结果 构建的含天然及优化序列的重组质粒酶切均可得到相应大小的插入片段,与预期相符,测序结果表明序列和阅读框均正确.线性化的重组质粒转入GS115后,得到7个不同的高拷贝阳性转化子,均能表达重组肽并具有良好的抑菌活性.结论 本研究成功构建含天然及优化hPAB-β序列的重组毕赤酵母工程菌,能够用于肽抗生素hPAB-β的制备.     

免疫调节性寡聚脱氧核苷酸筛选方法的建立、优化和应用

目的:建立一套合理而便捷的实验体系,为开发新型免疫调节性寡聚脱氧核苷酸(ODN)提供筛选方法。方法:利用含有CpG基序的免疫刺激性寡聚脱氧核苷酸(CpG ODN)作为刺激物,将人外周血单个核细胞(PBMC)作为研究对象,分别以细胞的增殖程度和刺激上清的抗病毒活性作为检测指标,优化各项实验条件,综合评定寡聚脱氧核苷酸的免疫调节活性。结果:成功建立了由阳性免疫调节性ODNA151抑制CpG ODN诱导的人PBMC增殖及抗病毒活性的筛选方法。结论:免疫调节性ODN筛选方法的成功建立,为下一步研究开发新型免疫调节性ODN奠定了基础。     

极高频电磁波对恶性肿瘤化疗患者外周血辅助淋巴细胞亚群Th1/Th2免疫应答平衡的影响

目的研究极高频电磁复合波对晚期恶性肿瘤患者外周血辅助淋巴细胞亚群Th1/Th2免疫应答平衡的影响。方法对32例恶性肿瘤患者化疗后进行极高频电磁复合波幅照,并采用ELISA法检测幅照治疗前、后外周血中的IFN-γ和IL-4水平变化;另对30例恶性肿瘤化疗后患者,同比进行细胞因子检测;再分别对上述患者外周血进行IFN-γ和IL-4水平变化的自身对照研究,以评价极高频电磁复合波对恶性肿瘤患者化疗后免疫功能的影响。结果①恶性肿瘤化疗后第8天,患者IFN-γ水平(24.66±12.85)pg·mL-1低于化疗后第3天水平(27.88±17.07)pg·mL-1,但未见显著性差异(P>0.05);而IL-4水平(54.80±28.56)pg·mL-1则明显地高于化疗后第3天水平(44.97±27.53)pg·mL-1,P<0.05。②极高频电磁复合波幅照的化疗患者,化疗后第8天,IFN-γ水平(34.79±27.23)pg·mL-1远高于化疗后第3天水平(20.39±12.67)pg·mL-1,P<0.05;IL-4水平变化研究结果显示,化疗后第8天,患者的IL-4水平(43.49±34.04)pg·mL-1高于化疗后第3天水平(35.77±22.23)pg·mL-1,但其间差异无显著性(P>0.05)。③恶性肿瘤患者化疗后第3天至第8天,细胞因子IFN-γ/IL-4水平比值降低,其间有显著性差异(P<0.05);经极高频电磁复合波幅照后,其比值明显升高[从(0.57±0.44)pg·mL-1升至(0.80±0.67)pg·mL-1],P<0.05。结论恶性肿瘤患者化疗后第3天至第8天,细胞因子IFN-γ水平降低,而IL-4水平则明显升高,反映恶性肿瘤化疗后患者Th细胞的存在异常(Th2)漂移;但极高频电磁复合波幅照治疗,可干预或阻抑恶性肿瘤患者化疗后Th细胞的异常漂移。     

湖南汉族人群HLA-DR位点等位基因多态性与鼻咽癌的相关性研究

目的：探讨湖南汉族人群HLA-DR位点等位基因多态性与鼻咽癌遗传易感性之间的关系。 方法： 应用PCR/SSO基因分型技术对93例湖南汉族鼻咽癌患者和93例健康对照作HLA-DRB1、-DRB3、-DRB4、-DRB5基因分型，采用χ2检验比较两组各位点等位基因频率、单倍型频率分布的差异。 结果： NPC组DRB1*1101明显低于对照组，DRB1*0801明显高于对照组, 但P值经Bonferroni校正后，差异均无显著（Pc>0.05）。 结论： 湖南汉族人群HLA-DR位点与鼻咽癌无明显相关。     

Fast- and slow-twitch isoforms (SERCA1 and SERCA2a) of sarcoplasmic reticulum Ca-ATPase are expressed simultaneously in chronically stimulated muscle fibers

 Using an immunohistochemical double-labeling technique, we observed that different isoforms of sarcoplasmic reticulum Ca-ATPase are co-expressed in single fibers of canine fast-twitch skeletal muscles stimulated chronically at low frequency. By 7 days of neuromuscular stimulation, the population of hybrid fibers expressing both SERCA1 and SERCA2a [fast- and slow-twitch isoforms of sarco(endo)plasmic reticulum Ca²⁺-ATPase] had increased from 1.5% to 9.2% of fibers. By 14 days of stimulation 90% of the pure fast-twitch fibers (expressing only SERCA1) were replaced by hybrid fibers. An additional 28 days of stimulation caused all fast-twitch fibers to express SERCA2a at the same level as found in nonstimulated slow-twitch fibers (expressing only SERCA2a). At this time, one-half of the previously hybrid fibers had become pure slow-twitch fibers. The remaining one-half of the hybrid fibers expressed SERCA1 at a very low level. Extending stimulation to 70 days did not further change the percentage of fibers that were slow-twitch or hybrid. Immunoblot studies at the whole-muscle level confirmed that changes in SERCA expression at 42 days of neuromuscular stimulation were complete. Immunohistochemical analysis of longitudinal sections of muscle showed that the changes in SERCA protein were uniform along the length of the muscle fiber, indicating that nuclei along its length responded equally to chronic stimulation. Received: 12 November 1996 / Received after revision and accepted: 16 December 1996     

TP73-AS1在肿瘤中的表达及调控作用

<正>随着高通量测序技术的发展,成千上万种长链非编码RNA(long non-coding RNA,lncRNA)进入人们的视野。lncRNA是一类长度超过200个核苷酸并缺少开放阅读框的不具备蛋白质编码功能的RNA~([1-2])。研究发现lncRNA参与诸多生物学进程的关键步骤,包括染色质重塑、基因转录、转录后调节和蛋白质翻译等~([3-5])。LncRNA机制的不断被阐明,也为肿瘤的研究提供了新的可能。LncRNA在多种肿瘤的增殖、迁移侵袭和抗凋亡     

Mature cystic teratoma of the ovary associated with complete colonic wall and mucinous cystadenoma

Mature cystic teratomas of the ovary frequently contain intestinal type epithelium, but they are rarely associated with complete intestinal wall. The association of mature cystic teratoma with mucinous cystadenoma is not unusual. However, the pathogenetic relationship between these two lesions remains unanswered. We report a mature cystic teratoma of the ovary in a 16-yr old female that contained a complete colonic wall in continuity with an endocervical-type mucinous cystadenoma. Both the mucinous cystadenoma and the colonic wall showed the typical histopathological and immunohistochemical patterns of classical mucinous cystadenoma (positive for CK7, negative for CK20) and normal colonic wall (positive for CK20, negative for CK7), respectively. The microscopic and immunohistochemical patterns of the epithelium from the transitional zone between colonic wall-like structure and mucinous cystadenoma demonstrated features of both types of epithelium, positive for both CK7 and CK20, and focally positive for a neuroendocrine marker, chromogranin, which is normally present in colonic mucosa. These results suggest that the mucinous cystadenoma originated from the colonic epithelium of the mature cystic teratoma.