尼莫地平对烫伤大鼠脑内ZO-1 mRNA及血脑屏障通透性的影响

目的:观察尼莫地平对严重烫伤大鼠脑内紧密连接相关蛋白ZO-1mRNA及血脑屏障通透性的影响。方法:实验于2005-04/10在南昌大学基础医学院应用解剖实验室完成。①取健康SD大鼠132只分为正常对照组12只、烫伤组60只,尼莫地平组60只,后两组又设烫伤后1,3,6,12,24h5个时间点,每个时间点12只,其中6只用于脑组织伊文思蓝含量的测定,剩余6只用于ZO-1mRNA的检测。②烫伤组和尼莫地平组大鼠100℃开水烫伤15s,造成背部30%体表总面积Ⅲ度烧伤。尼莫地平组大鼠于烫伤后即刻腹腔注射尼莫地平(0.5mg/kg),其他2组不给药。③各组大鼠于相应的时间点麻醉并处死动物取材,应用化学定量方法检测大鼠脑组织内伊文思蓝含量,运用RT-PCR方法检测大鼠脑内ZO-1mRNA的表达变化。结果:经补充后132只大鼠进入结果分析。①大脑伊文思蓝含量:正常对照组为(10.18±1.79)μg/g,烫伤组伤后1,3,6,12h均高于正常对照组(P<0.05),其高峰在烫伤后6h,为(20.00±0.58)μg/g;尼莫地平组伤后1,6,12h均低于烫伤组(P<0.01),烫伤后6h时为(16.74±0.78)μg/g。②小脑伊文思蓝含量:正常对照组为(12.90±1.32)μg/g,烫伤组伤后1,3,6,12h均高于正常对照组(P<0.05),其高峰在烫伤后6h,为(31.3±1.47)μg/g;尼莫地平组伤后1,3,6,12h均低于烫伤组(P<0.01),烫伤后6h时为(21.05±2.36)μg/g。③脑组织ZO-1mRNA的表达:烫伤组烫伤后3,6,12,24h分别为正常对照组的(0.1235±0.0158),(0.1890±0.0531),(0.2014±0.0412),(0.1555±0.0163)倍(P<0.01);尼莫地平组较烫伤组高,以烫伤后3,6h最为明显,分别为烫伤组的3.96及1.81倍(P<0.01).结论:①严重烫伤后血脑屏障通透性增高,脑内ZO-1mRNA表达下降。②烫伤后早期应用尼莫地平能防止脑内ZO-1mRNA表达下降,并能起到保护血脑屏障功能的作用。     

Loss of high-affinity thrombin receptors during platelet concentrate storage impairs the reactivity of platelets to thrombin

BACKGROUND: The storage of platelet concentrates (PCs) induces a reduction in the platelet surface expression of glycoprotein (GP) Ib alpha. The location of the platelets' high-affinity binding site for thrombin has been postulated as being located on GPIb alpha. This study attempts to determine whether loss or alteration of GPIb alpha during storage of PCs is related to impairment in the reactivity of platelets to thrombin. STUDY DESIGN AND METHODS: In this study, platelet surface expression of GPIb alpha was monitored by means of flow cytometry, throughout standard storage of PCs for up to 10 days. Two thrombin- induced platelet responses, the binding of radiolabeled fibrinogen and the platelet surface expression of P-selectin, were evaluated. Thrombin- binding assays were also performed to assess the number of thrombin receptors in platelets. RESULTS: The surface expression of the GPIb/IX complex declines during storage of PCs. The thrombin-induced maximal binding of fibrinogen in platelets stored for 3, 7, and 10 days was 77 +/? 7 percent, 60 +/? 20 percent, and 34 +/? 25 percent, respectively, of that found in fresh platelets. Moreover, the concentration of thrombin needed for 50 percent of platelets to express the CD62 antigen P-selectin at the surface increased from 0.05 U per mL in fresh platelets to 0.11, 0.56, and 1.2 U per mL in platelets stored for 3, 7, and 10 days, respectively. Thrombin-binding experiments demonstrated a significant reduction in the number of high-affinity binding sites throughout storage of PCs (55 +/? 21 sites/platelet in 10-day-stored platelets vs. 73 +/? 25 in fresh platelets). A significant correlation was also observed between the number of high-affinity thrombin-binding sites and surface expression of GPIb alpha. Selective blockage of the thrombin-binding site on GPIb alpha with monoclonal antibody LJ-Ib10 also inhibited the response of fresh platelets to thrombin, up to a level equivalent to that found in 3-day-stored platelets. CONCLUSION: The loss of the GPIb alpha-located high-affinity thrombin-binding site may impair the ability of platelets to become activated by thrombin as storage time increases.     

氧化应激对糖尿病肾病时细胞、细胞外基质及血管通透性的影响机制

目的:糖尿病肾病及其引起的终末期肾病近年来在全球的发病情况逐年提高,该病预后差、治疗费用高,成为世界范围内严重危害人类健康的公共卫生问题。糖尿病肾病发病机制错综复杂,氧化应激被认为是重要的共同的机制之一。本文探讨氧化应激对糖尿病肾病的影响。资料来源:应用计算机检索MEDLINE,CBM,CNKI数据库及手工检索1997-01/2006-11期间的相关文献。包括临床研究(不限研究对象的年龄、性别、种族。)和基础研究,不限体内或体外研究。中文检索词包括“氧化应激”,“活性氧类”,“糖尿病肾病”和“发病机制”;英文检索词有“diabetic nephropathies”,“oxidative stress”,“reactive oxygen species”,“PKC”和“TGF-β”。资料选择:共收集到相关文献991篇,阅读全部文章的文题和大部分文章的摘要。选择文献所述内容与糖尿病肾病时氧化应激作用相关的文献。排除重复性研究和Meta分析类文章。资料提炼:共得到符合纳入条件的文献142篇,排除849篇。选择其中30篇进行分析,其中英文25篇,中文5篇,英文有1篇为手工检索的增刊。资料综合:糖尿病肾病的发病机制错综复杂,肾脏的结构和功能变化包括高滤过、肾脏和肾小球的肥大、细胞外基质的堆积、肾小球基底膜的增厚和肾小球滤过屏障功能的异常。这些变化是多因素共同作用的结果,在众多发病机制中,氧化应激被认为是共同机制之一。在正常情况下,活性氧的产生和抗活性氧水平二者处于平衡状态,当活性氧蓄积过多就会攻击机体,即氧化应激。氧化应激的产生主要是活性氧类产生过多和清除减少以及糖尿病肾病患者体内氧化应激水平增加导致的。氧化应激对糖尿病肾病的影响包括活性氧类可以增加细胞膜的通透性;使肾细胞内的谷胱甘肽过氧化物酶、超氧化物歧化酶和过氧化氢酶等抗氧化酶发生糖化或氧化,肾组织抗氧化能力降低,细胞内关键酶和转运蛋白Na-K-ATP酶失活等。结论:氧化应激作用可以增加细胞膜的通透性,使肾组织抗氧化能力降低,是糖尿病肾病的重要发病机制之一。     

Sentinel lymph node biopsy in melanoma: Which hot nodes should be harvested and is blue dye really necessary?

Objectives

The ‘10% rule’ has become widely accepted by surgeons performing sentinel lymph node biopsy (SLNB) for melanoma. The purpose of this study was to compare the ‘10% rule’ with alternative node harvesting criteria. In particular, we were interested to see whether the use of blue dye had any impact on the sensitivity of the test and whether it is necessary to remove all hot nodes.

Plasma homocysteine, a risk factor for cardiovascular disease, is lowered by physiological doses of folic acid

Elevated plasma homocysteine, an independent risk factor for cardiovascular disease (CVD) can be lowered by administration of pharmacological doses of folic acid. The effect of lower doses in apparently normal subjects is currently unknown but is highly relevant to the question of food fortification. Healthy male volunteers (n = 30) participated in a chronic intervention study (26 weeks). Folic acid supplements were administered daily at doses increasing from 100 micrograms (6 weeks), to 200 micrograms (6 weeks), to 400 micrograms (14 weeks). Fasting blood samples collected before, during and 10 weeks post intervention were analysed for plasma homocysteine, serum and red- cell folate levels. Results, expressed as tertiles of baseline plasma homocysteine concentration, showed significant (p < or = 0.001) homocysteine lowering in the top (10.90 +/- 0.83 mumol/l) and middle (9.11 +/- 0.49 mumol/l) tertiles only. In the low tertile, where the mean baseline homocysteine level was 7.07 +/- 0.84 mumol/l, no significant response was observed. Of the three folic acid doses, 200 micrograms appeared to be as effective as 400 micrograms, while 100 micrograms was clearly not optimal. There is thus a minimal level of plasma homocysteine below which folic acid has no further lowering effect, probably because an optimal folate status has been reached. A dose as low as 200 micrograms/day of folic acid is effective in lowering plasma homocysteine concentrations in apparently normal subjects. Any public health programme for lowering homocysteine levels, with the goal of diminishing CVD risk, should not be based on unnecessarily high doses of folic acid.      

锻炼心理学中动机理论：自我决定理论的新进展

目的:对锻炼心理学中的自我决定理论进行简要概述与分析。资料来源:检索中国期刊网、EBSCO和UMI资料库1997-01/2006-10有关自我决定理论的文献,检索词(限制为标题)为“self-determination theory,sport and exercise”,限定语言种类为英文。资料选择:对所获得的文献进行仔细研读,从中选择有关自我决定理论在锻炼心理学中实证研究的文章,排除重复研究类文章。资料提炼:在53篇文献中,删除7篇内容重复的文献;对46篇文献进行分类整理,其中30篇选为参考文献。资料综合:自我决定论是新近发展起来的一种认知动机理论,代表着当下动机理论研究的趋向。它把人类的动机看成是一个从外在调节到内在动机之间的动态的连续体,并依据自主的程度对动机的类型进行了详细的划分,同时从满足人们基本心理需要的角度对促进外在动机内化的条件进行了探讨。结论:自我决定理论还有许多待以完善的地方,关于自我决定理论的一些假设还有待于进一步的验证。     

大鼠海马注射β-淀粉样蛋白1-40后β位淀粉样前体蛋白裂解酶1mRNA表达及加减地黄饮子提取物的干预烛

目的：观察SD大鼠海马立体定向注射β-淀粉样蛋白1-40后β位淀粉样前体蛋白裂解酶1mRNA表达的变化及加减地黄饮子对其的干预作用。方法：①实验于2005-09／2006-09在齐齐哈尔医学院医药科学研究所完成。②选用100只SD大鼠随机分为空白对照组、假手术对照组、模型对照组、盐酸多奈哌齐组、加减地黄饮子组共5组，每组20只。通过海马立体定向注射β-淀粉样蛋白，40诱导老年性痴呆动物模型。③盐酸多奈哌齐按0.33mg，（kg·d）给药，加减地黄饮子组按1.0g，（kg·d）给药，共给药28d。空白对照组和假手术对照组给予等量生理盐水。④第5周处死大鼠，应用实时定量PCR法检测大脑海马组织13位淀粉样前体蛋白裂解酶1mRNA表达（用2^-△△ct表示，Ct为阈循环值，△Ct=Ctbace1CtGAPDH，△△Ct=△Ct各干预组-△Ct空白对照组）。⑤多组间差异的显著性分析用单因素方差分析，组间两两比较运用LSD-f检验。结果：实验选用100只大鼠，每组随机选5只用于抽提大脑海马组织总RNA，因此共有25只大鼠纳入结果分析。β位淀粉样前体蛋白裂解酶12^-△△ct值模型组（4.67±0.52）显著高于假手术对照组（1.07±0.08）（P〈0.01），表明模型组B位淀粉样前体蛋白裂解酶1mRNA表达上调。盐酸多奈哌齐组（1.80±0.23）和加减地黄饮子组（1.26±0.20）显著低于模型对照组，表明13位淀粉样前体蛋白裂解酶1mRNA表达下调。结论：大鼠大脑海马注射β-淀粉样蛋白，40后海马组织β位淀粉样前体蛋白裂解酶1mRNA表达水平明显增高，加减地黄饮子提取物可以抑制海马组织β位淀粉样前体蛋白裂解酶1mRNA的表达，从而发挥抗老年性痴呆的作用。     

Predictors of One Year Outcome in Lupus Nephritis: The Importance of Renal Biopsy

The short-term prognosis of lupus nephritis was evaluated byassessing serum creatinine 12 months after renal biopsy in 87patients with lupus nephritis. On univariate analysis, significantclinical and laboratory predictors of this outcome includedclinical signs of renal injury (serum creatinine, 24-hour urinaryprotein, prolonged renal disease, nephrotic syndrome, serumalbumin), as well as thrombocytopenia, older age, and coexistingillness or hypertension at the time of biopsy. On renal biopsy,diffuse proliferative nephritis, higher activity, chronicity,or tubulointerstitial scores, or subendothelial or subepithelialelectron dense deposits predicted a higher serum creatinine12 months after biopsy. A clinical predictive model was developed which included asindependent predictors serum creatinine, age, platelet countand 24-hour urinary protein. Any one of three biopsy variablesadded information to the clinical prediction model: a markedquantity of subendothelial deposits (p=0.02), a higher activityindex score (p=0.02), or the presence of diffuse proliferativelupus nephritis (p=0.05). However, the relative predictive accuracyof the clinical model did not improve with the addition of anyof the biopsy variables. The value of renal biopsy in lupus nephritis is discussed basedon the ability of biopsy information to confirm the prognosis,to add new predictive information for a group of subjects, andto improve predictive accuracy for individual patients.     

Infection or suspected infection after hip replacement surgery with autologous or homologous blood transfusions

Homologous blood transfusions have been associated in both animals and humans with an increased risk of acute postoperative infectious complications. Eighty-four patients who underwent hip replacement surgery and were transfused with 2 or 3 units of blood were analyzed to determine whether those receiving homologous transfusions had different outcomes than those receiving autologous blood only. Only patients free of other risks for postoperative infection were studied. Those receiving homologous blood had a 32 percent (16/50) rate of proven or suspected infections, which was significantly higher than the 3 percent (1/34) rate in patients receiving autologous blood (p = 0.0029). Wound infections accounted for only a minority (6/17) of the proven or suspected infections, which suggests that nonsurgical factors contributed to these complications. The patients identified as being infected required significantly more antibiotic therapy (mean, 7.6 days) and lengthier hospital stays (mean, 15.5 days) than the patients who remained free of evidence of infection (means: 2.3 days of antibiotics and 12.3 days in the hospital) (p = 0.0001 for each variable). Other potential risk factors for infection, such as duration of surgical procedure, advanced patient age, amount of blood loss, type of anesthesia, surgeon performing the operation, use of a cemented versus porous-coat prosthesis, leukocytopenia, anemia, and underlying medical diagnosis, did not account for the differences in infection rates seen in those receiving homologous and autologous transfusions. These results confirm previous reports of an increased risk of postoperative infection in patients receiving homologous transfusions. Homologous transfusion may contribute to an increased risk of infection by immunologic modulation of the recipient.(ABSTRACT TRUNCATED AT 250 WORDS)     

Mycobacterial Infections After Renal Transplantation

Mycobacterial infections occurred in 11 of 633 (1.7 per cent)recipients of successful renal transplants. There were no casesof tuberculosis in patients receiving chemoprophylaxis, butamongst those who did not receive prophylaxis disease occurredin six of the 27 (22 per cent) high-risk patients. The majorcause of morbidity during treatment was renal allograft rejection,largely due to reduction in immunosuppressive drug therapy.