雷帕霉素对炎性反应状态下肾小球系膜细胞内脂质稳态的影响

Objective To investigate the effect of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanism. Methods Glomerular mesangial cell line (HMCL) cells were cultured and divided into control group, IL-1β group and different concentration rapamycin groups. Intracellular cholesterol accumulation was observed and measured by oil O staining and HPLC. Real-time quantitative PCR and Western blot were used to detect the mRNA and protein expression of LDLR, PPARγ, LXRα, ABCA1 in HMCL after the treatment with IL-1β and rapamycin. Results Rapamycin had no significant influence on intracellular cholesterol concentration under normal condition. IL-1β significantly increased the intracellular cholesterol concentration by 143％ of control (P<0.05), and 10, 50, 100 ?滋g/L rapamycin could significantly inhibit the effect of IL-1β (87％, 116％, 96％ of control respectively, all P<0.05). Rapamycin could suppress the increased expression of LDLR caused by IL-1β on both mRNA and protein level in a dose-dependent manner（P<0.01）. Rapamycin dose-dependently up-regulated the reduced mRNA and protein expression of ABCA1, the decreased mRNA expression of PPARγ and LXRα induced by IL-1β as well (P<0.01）. Conclusion Rapamycin may contribute to the maintenance of intracellular cholesterol homeostasis in glomerular mesangial cells under inflammatory state by both reducing cholesterol uptake and promoting cholesterol efflux.     

蛋白酶对降低异常精液粘稠度的实验对比研究

目的通过不同蛋白酶类对降低高粘稠度精液的粘稠度效果对比,寻找理想的降低精液粘稠度的药物。方法将高粘稠度精液标本分为两组,A组:31例采用α-糜蛋白酶降低精液粘稠度:B组:32例采用尿激酶降低精液粘稠度;两组均观察用药前后的精子活动力。采用配对t检验和单因素方差分析对所得数据作统计学处理。结果高粘稠度精液用药物(α-糜蛋白酶或者尿激酶)液化精液后,精子的活动力较用药前有明显提高(P<0．001);用药前后精液的粘稠度都存在着明显的差异,精液的粘稠度分别下降44．83％和55．45％(P<0．001);在A组和B组的对比研究中,单因素方差分析检验提示:用药后两组间粘稠度数据有显著的差异(P<0．001￡(?)。结论蛋白酶可以有效地降低异常精液粘稠度的精液,从实验结果提示尿激酶降低精液粘稠度的效果优于α-糜蛋白酶,这有助于临床开展应用性研究和治疗。     

多发性骨髓瘤合并肾功能不全38例临床和预后分析

目的研究多发性骨髓瘤合并肾功能不全的临床特点及肾功能可逆性的相关因素和生存相关因素。方法回顾性分析1999-01~2003-12北京协和医院收治的91例初治多发性骨髓瘤及其中38例多发性骨髓瘤合并肾功能不全患者的临床资料。结果91例初治多发性骨髓瘤中有38例(41·8%)合并肾功能不全。合并肾功能不全的患者病程进展更快,贫血更严重,血乳酸脱氢酶(LDH)和β2-微球蛋白(β2-MG)质量浓度更高,以及尿蛋白量更多,同时对化疗的反应更差及生存时间更短。其中34·2%的患者肾功能不全是可逆的,血肌酐和LDH是肾功能可逆的独立预测因素。肾功能可逆患者的生存时间与肾功能正常患者的生存时间比较差异无显著性意义。Cox生存多因素分析发现肾功能可逆性(B=1·294,EXP(B)=3·647,P=0·001)是与生存惟一相关的因素。结论肾功能不全是多发性骨髓瘤常见并发症,相当一部分患者的肾功能可以恢复正常,血肌酐水平和LDH水平是肾功能可逆的重要因素,肾功能可逆性是独立的生存预后因素。     

慢性肾功能不全患者血管活性物质测定在血液净化中的临床研究

目的 评价血管紧张素Ⅱ、氨甲酰血红蛋白、醛固酮及甲状旁腺激素等在血液净化充分性中的意义。方法 120例慢性肾功能衰竭患者，按采用不同的透析膜分为3组：即聚砜膜、醋酸膜、铜仿膜。用放射免疫法测定其血管紧张素Ⅱ（AngⅡ）及醛固酮（ALD）浓度，化学发光法测甲状旁腺激素（PTH）。采用不同的血流量200ml／min及250ml／min比较。结果 对体内中、小分子物质清除率，聚砜膜〉醋酸膜〉铜仿膜。结论 高血流量、高通透性人工合成聚砜膜，对治疗慢性肾功能衰竭，提高肾功能不全患者的身心健康及生活质量、延长患者生命有很重要的临床意义。     

Using rare earth element tracers and neutron activation analysis to study rill erosion process.

Spatially averaged soil erosion data provide little information on the process of rill erosion. The dynamically varied data on the temporal and spatial distributions in the rill erosion process are needed to better understand the erosion process and reveal its innate characteristics. The objectives of this study were to examine the feasibility and effectiveness of rare earth element (REE) tracers and the neutron activation analysis (NAA) method on the study of the rill erosion process and to reveal quantitatively the relationships and characteristics of temporal and spatial distributions of sediment yield in rill erosion. Four REEs were used to study the changeable process of rill erosion at 4 slope positions. Four water inflow rates were applied to a 0.3 x 5 m soil bed at 3 slopes of 10.5%, 15.8% and 21.2% in scouring experiments. All of the runoff was collected in the experiment. Each sample was air-dried and well mixed. Then 20 g of each sample was sieved through 100-mesh and about a 50 mg sample was weighed for analysis of the four elemental compositions by NAA. Results indicate that the REE tracers and NAA method can be used to not only quantitatively determine soil erosion amounts on different slope segments, but also to reveal the changeable process of rill erosion amount. All of the relative errors of the experimental results were less than 25%, which is considered satisfactory on the study of rill erosion process.     

γ-H2AX分析用于检测电离辐射致HepG2细胞DNA双链断裂的研究

目的 应用γ-H2AX分析检测电离辐射导致肝癌细胞株HepG2基因组DNA双链断裂的情况，并检测在不同细胞周期时相中的表达差异，从而了解不同时相HepG2细胞株的辐射敏感性。方法利用胸腺嘧啶核苷（TdR）阻断HepG2细胞于G1期末，于不同时间点分别得到同步化的S期和G2/M期细胞，用60Coγ射线照射细胞，建立DNA双链断裂模型，采用免疫荧光法和Westemblotting检测γ-H2AX的表达。结果TdR阻断后继续培养至34和40h，分别得到了较高同步化程度的S期和G2／M期HepG2细胞；受照后的HepG2细胞中Y-H2AX表达较照射前显著增高，处于S期的细胞γ-H2AX表达增加更为突出。结论不同周期时相的HepG2细胞受照后均检测出不同程度的DNA双链断裂，其中S期细胞尤为敏感。γ-H2AX对DNA双链断裂快速敏感的反应使γ-H2AX分析在检测早期DNA双链损伤中具有广泛的廊用前景。     

The role of endotoxin in the pathogenesis of experimental multiple system organ failure: a preliminary report.

In this study, an animal model of multiple system organ failure (MSOF) in rabbits, engendered by feeding E. coli prior to severe hemorrhagic shock, was used for the purpose of investigating 1) the relationship between lipopolysaccharide (LPS) and MSOF, and 2) the effectiveness of Re-LPS antiserum in preventing MSOF. The results showed that endotoxemia occurred very early, and its degree correlated well with that of organ dysfunction. Re-LPS antiserum administration abated the toxic effects and lowered the incidence of MSOF. These results suggest that sequential analysis of circulating LPS levels may be useful for the early diagnosis of MSOF, and that gut-derived endotoxin might play an important role in the pathogenesis of experimental MSOF.     

兔颈椎终板胶原结构变化对运动节段力学性能的影响

目的 通过测定兔退变颈椎运动节段力学参数的改变,观测其软骨终板胶原的超微结构变化,为退变的椎间盘显现异常力学特性作材料结构上的探讨。方法 将24只家兔随机分为对照组和模型组,模型组家兔保持45°低屈曲位5 h/d,取C5,6、C6,7进行生物力学测定,同时电镜观察终板胶原组织结构改变,总结分析终板材料的结构变化对运动节段力学性能的影响。结果 模型组终板抗扭强度、抗压强度、断裂时的最大形变都低于对照组,胶原排列从有序、致密、规整到紊乱、松散、溶解,并随造模进程的深入而加剧。结论 长时间的应力不均状态,造成椎间盘终板材料力学特性改变;终板胶原结构改变是颈椎间盘生物力学性能减退的原因之一。     

日本血吸虫磷酸丙糖异构酶编码基因的克隆与序列测定

目的克隆和鉴定日本血吸虫磷酸丙糖异构酶(SjTPI)编码基因,为寻找血吸虫病的候选疫苗联合应用打基础.方法设计合成引物,抽提日本血吸虫成虫总RNA,用RT-PCR法从中扩增出SjTPI基因编码序列,将其克隆入pGEM-T载体,用双酶切、以重组质粒为模板进行PCR扩增和测序进行鉴定.结果 RT-PCR法从成虫总RNA中扩增出大小为759 bp SjTPI基因编码序列,重组质粒pGEM-SjTPI经双酶切、PCR扩增,均可获得一条与RT-PCR产物一致的DNA片段,序列测定结果表明具有一个长度为759 bp的完整开放阅读框,与日本血吸虫(菲律宾株)和曼氏血吸虫磷酸丙糖异构酶核苷酸序列有高度同源性(分别为99%和88%).结论该实验成功地克隆了SjTPI编码基因,为进一步研究提供了条件.     

Role of intestinal bifidobacteria in the pathogenesis of gut-derived bacteria/endotoxin translocation and the effect of bifidobacterial supplement on gut barrier function following burns

Early multiple organ dysfunction syndrome appears to be facilitated with bacterial translocation in severely burn injury, yet the mechanisms of bacterial translocation remains in dispute. The aim of this study was to investigate the potential role of intestinal bifidobacteria in the pathogenesis of gut-derived bacteria/endotoxin translocation following burns and the effects of bifidobacterial supplement on gut barrier. Methods: Wistar rats were randomly divided into burn group (Burn, n=60),sham burn group (SB, n=10) in experiment Ⅰ , and burn + saline group (BS, n=30), burn + bifidobacteria group (BB, n=30), and sham-burn + saline group (SS, n= 10) in experiment Ⅱ. Animals in BB group were fed bifidobacterial preparation (5 × 109 CFU/ml) after burns, 1.5ml,twice daily. Animals in BS and SS were fed saline. Samples were taken on days 1, 3, and 5 in burn groups, and on day 3 in sham-burn groups. The incidence of bacteria/endotoxin translocation and counts of Bifidobacterium, Fungi and Escherichia coli in gut mucosa were determined with standard methods. The levels of sIgA in mucus of small intestine were measured by RIA. The positive sIgA expression in lamina propria and ileum mucosal injury was evaluated light microscopically by blinded examiners. Results: Our results showed that the incidence of bacterial translocation was increased after burns, which was accompanied by significant decrease in number of bifidobacteria but significant increase in E. coli and fungi in gut mucosa, and elevation of levels of plasma endotoxin and IL-6 (P<0. 001).The incidence of bacterial translocation was markedly reduced after 3- and 5-day supplementation of bifidobacteria compared with control group (P<0.05). The counts of mucosal bifidobacteria were increased by 4- to 40-fold,while E. coli and fungi were decreased by 2- to 30-fold and 10- to 150-fold, respectively, after bifidobacterial supplementation in contrast to control group. The damage of mucosa tended to be less pronounced after 3-day bifidobacteria-supplemented formula compared with control group [grade 2(0-6) vs. grade 4(3-6), P<0.05]. Moreover, the expression and release of sIgA was markedly augmented after 3-day bifidobacteria-supplementation formula and it returned to normal range on day 5. Conclusion: The decrease in counts and proportion of bifidobacteria in mucous membrane flora may play an important role in the development of bacteria/endotoxin translocation following thermal injury. The supplement of exogenous bifidobacteria could per se improve gut barriers, and attenuate bacteria/endotoxin translocation secondary to major burns.