Recapitulation of fast skeletal muscle development in zebrafish by transgenic expression of GFP under the mylz2 promoter.

A 1,934-bp muscle-specific promoter from the zebrafish mylz2 gene was isolated and characterized by transgenic analysis. By using a series of 5' promoter deletions linked to the green fluorescent protein (gfp) reporter gene, transient transgenic analysis indicated that the strength of promoter activity appeared to correlate to the number of muscle cis-elements in the promoter and that a minimal -77-bp region was sufficient for a relatively strong promoter activity in muscle cells. Stable transgenic lines were obtained from several mylz2-gfp constructs. GFP expression in the 1,934-bp promoter transgenic lines mimicked well the expression pattern of endogenous mylz2 mRNA in both somitic muscle and nonsomitic muscles, including fin, eye, jaw, and gill muscles. An identical pattern of GFP expression, although at a much lower level, was observed from a transgenic line with a shorter 871-bp promoter. Our observation indicates that there is no distinct cis-element for activation of mylz2 in different skeletal muscles. Furthermore, RNA encoding a dominant negative form of cAMP-dependent protein kinase A was injected into mylz2-gfp transgenic embryos and GFP expression was significantly reduced due to an expanded slow muscle development at the expense of GFP-expressing fast muscle. The mylz2-gfp transgene was also transferred into two zebrafish mutants, spadetail and chordino, and several novel phenotypes in muscle development in these mutants were discovered.     

特异性DNA倍增技术检测t-PA cDNA基因在表达细胞中的稳定性

利用特异性DNA倍增技术(polymerase chain Reaction,PCR)检测t-PA cDNA基因在表达细胞基因组中的稳定性,并对所得的PCR反应产物进行了限制性内切酶片段、分子杂交和核苷酸顺序分析等方面的研究,证实了t-PA cDNA基因已插入到表达细胞染色体中。这种方法快速、简便、灵敏度和特异性高,是检测基因工程表达细胞中cDNA基因稳定整合状况的好方法。     

Role of endothelin in the pathogenesis of hypertension in spontaneously hypertensive and 2 kidneys 1 clip rats.

The plasma endothelin (ET) level in spontaneously hypertensive rats (SHR) and 2K1C hypertension animal models and its vasoconstrictive effect on renal and tail arteries were studied. The results demonstrated that there was no difference in plasma ET level between the hypertensive groups SHR, 2K1C, normotensive control groups Wistar Kyot (WKY) and Sprague Dawley (SD), while the vasoconstrictive effect of ET in SHR was more dominant than in WKY. The EC50 of the renal and tail arteries in SHR (0.8912 +/- 0.1662 x 10(-8) M, 0.6103 +/- 0.0878 x 10(-8) M) was apparently lower than that in WKY (1.77 +/- 0.2991 x 10(-8) M, 1.2267 +/- 0.2502 x 10(-8) M, P less than 0.05), but no difference was found in 2K1C and SD rats. The four groups of animals exhibited no difference of such effects as response to norepine-phrine (NA). The findings suggested that the increased arteriole sensitivity to ET be an important factor in the pathogenesis of hypertension in SHR.

     

572例近视眼患者中央角膜厚度测量报告

本文作者在572例(1144只眼)近视眼患者拟行角膜放射状切开(RK)手术前,对角膜不同部位厚度进行了测量,对其值作统计学处理,均值及标准差为0.527±0.037mm,标准误为0.002,说明我国95％的近视眼患者中央角膜厚度范围为0.455—0.600mm。提示我国成人各年龄组左、右眼角膜厚度与左、右眼屈光度、性别、眼别无关。强调RK手术前对角膜厚度测量的重要性,但手术预后优劣为多因素所致。     

The platelet interactivity phenotype of Streptococcus sanguis influences the course of experimental endocarditis.

A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor.     

经内镜胆管引流术在肝门部恶性胆管梗阻中的应用及其评价

肝门部恶性肿瘤手术切除率极低，临床处理十分棘手。作者采用内镜胆管引流术治疗此类肿瘤２８８例次（肝门部胆管癌１８４例、胆囊癌２３例、肝细胞癌侵犯肝门部胆管４７例、其他转移性肿瘤３４例），其中行内镜鼻胆管引流１６２例次、塑料内置管引流８０例次、放置可膨式金属胆道支架４６例、４例患者接受同期双内置管引流。引流总有效率为６７．０％，其中效果满意者４３．１％；４０例患者术后１个月内发生胆管炎，发生率为１３．８％，３例死亡；长期随访病例的平均存活期５．３个月。我们观察到治疗的效果与Ｂｉｓｍｕｔｈ分型有密切关系，如果全肝４０％以上的胆系得到引流，黄疸有望消退；左、右两侧胆管同时引流可扩大引流范围，提高疗效；应合理选择三种内镜胆管引流方法并适时灵活转换才能获得满意的疗效。结论：对于肝门部肿瘤，内镜胆管引流术是一种安全有效的治疗手段，可作为首选的姑息性治疗。     

镍作业工人细胞免疫功能、血清硒和过氧化脂质含量的变化

９６名镍作业工人测定结果：非特异酯酶阳性细胞百分率（ＡＮＡＥ＋％）为７６．８％±８．０％，Ｔ细胞亚群ＣＤ２、ＣＤ４、ＣＤ８阳性细胞百分率（ＣＤ＋２％、ＣＤ＋４％、ＣＤ＋８％）及ＣＤ＋４／ＣＤ＋８比值分别为６５．６％±１０．５％、５６．３％±１２．１％、３４．３％±８．２％和１．７６±０．６；酵母多糖刺激的外周血多形核白细胞化学发光（ＰＭＮ－ＣＬ）本底和峰值分别为４８±２３和３０７３±６８４ＣＰＳ／１０６ＰＭＮ；血清硒和丙二醛含量分别为１．２２±０．２３和４．７６±０．８８μｍｏｌ／Ｌ。与非镍作业的地区对照组比较，Ｔ细胞ＣＤ＋８％增高，ＣＤ＋４／ＣＤ＋８比值下降，化学发光的本底值降低，峰值增加，血清Ｓｅ含量下降，丙二醛含量升高。分析镍作业工人工龄与后三项指标变化的关系，工龄大于２０年与小于１０年有统计学上明显差别。这些观察指标为镍作业人员医学观察增加新的监护指标提供依据。     

X-刀立体定向放射治疗颅内肿瘤的近期疗效分析

目的:分析立体定向X-刀放射治疗颅内肿瘤后的近期疗效,并进行阶段性工作总结。材料和方法:53例不同类型脑瘤患者,以CT、MR、DSA图像资料作为定位依据,用德国Brain LAB治疗计划系统设计三维优化方案,西门子MD-2型直线加速器旋转照射。结果:53例患者经X-刀治疗后,近期均取得了满意效果,诸如以卡氏评分法评价,临床症状有所改善;以CT增强扫描复查观察,肿瘤大小趋于缩小或消失。结论:立体定向放射治疗后的追踪观察表明,只要严格掌握适应症,精确定位,精确计划,精心治疗,X-刀是一种安全、有效、无痛苦的治疗脑肿瘤的方法。它可起到改善临床症状,提高患者生活质量,延长生存期限的作用。     

Complement Killing of Yersinia enterocolitica and Retention of the Bacteria by Leucocyte Removal Filters

We report studies on the complement sensitivity of four strains of Yersinia enterocolitica , serotypes O:3, O:9, O:5,27, and O:20, isolated from blood units involved in transfusion fatalities. Complement in fresh CPD plasma killed Y. enterocolitica within 4 h at 22°C in 100% of the experiments. The bactericidal action was serotype and complement activation pathway dependent. Both classic and alternate pathways seemed to be active, but the latter to a lesser degree. When the classic pathway was blocked by chelation of Ca²⁺ no complete killing was obtained. Complement did not enhance or condition Yersinia for leucocyte filter retention. Direct removal of Yersinia by filtration was also related to serotype; all strains were reduced by filtration in heat-inactivated plasma, and all except serotype O:5,27 were reduced in Ca²⁺ -chelated plasma. Our findings may explain why plasma products and platelet concentrates are rarely involved in Yersinia sepsis related to transfusion.