振动对急性缺氧小鼠肺损伤的影响

本文观察了频率为20Hz、振幅为0．67mm和作用时间为40min的振动预处理对急性缺氧小鼠肺损伤的影响。结果发现实验组的肺组织匀浆脂质过氧化物LghdPeroxde（LPO）、支气管肺泡灌洗液（BALF）中蛋白含量和白细胞数明显低于对照组（P＜0．05）。这表明在特定率数的振动作用下能明显减轻急性缺氧小鼠肺的损伤。     

非创伤性股骨头坏死患者的血液学改变

目的测定非创伤性股骨头坏死(nontraumaticosteonecrosisoffemoralhead,NONFH)患者的血液学指标变化,筛选敏感分子标记物用于早期诊断和筛选高危人群。方法研究对象共分三组:(1)NONFH早期组(塌陷前期)30例,(2)NONFH晚期组(塌陷后期)30例,(3)正常对照组30例。各组对象均抽取空腹肘静脉血。应用酶联免疫吸附法(ELISA)测定血小板α-颗粒膜蛋白(GMP-140)、血浆蛋白C(PC)、D-二聚体(D-Dimer)含量;发色底物法测定血浆纤溶酶原激活剂抑制剂(PAI)活性。结果(1)NONFH早、晚期组血小板GMP-140含量均高于正常对照组,血浆PC含量均低于正常对照组,D-Dimer含量均高于正常对照组,PAI活性均高于正常对照组(P均<0.05)。骨坏死情况越严重,各项指标上升或降低的趋势越明显,而且各项指标早、晚期组间比较差异均有显著性(P均<0.05)。(2)经判别分析,筛选出PAI、D-Dimer、PC三个指标,建立NONFH早期、晚期和正常对照三类判别函数式。NONFH早期:Y1=?26.3966 41.4916X10 0.0512X4 4.1390X1;NONFH晚期:Y2=?66.7566 82.1315X10 0.1082X4 2.7233X1;正常对照组:Y3=?26.7049 20.5695X10 0.0327X4 6.1900X1。回代判对率97.78%。结论(1)NONFH患者各期均存在高凝和低纤溶状态。(2)PAI、D-Dimer、PC为NONFH患者的血液学敏感指标。     

Chronic lithium treatment increases the phosphorylation of a 64-kDa protein in rat brains

Despite the wide clinical use of lithium in the treatment of manic depressive illness there is no adequate explanation for its mechanism of action. In the light of lithium's suggestive effects on the second messenger system in the brain, we studied the effects of chronic dietary lithium treatment (achieving blood levels in the therapeutic range) on protein phosphorylation in different areas of rat brain. An increase in the phosphorylation of a 64-kDa membrane-associated protein was evident in the lithium-treated rats compared to controls. This increase was observed only under basal phosphorylating conditions and was abolished when the phosphorylation was performed in the presence of Ca²⁺ or Ca²⁺ and calmodulin. The possibility that this 64-kDa protein affected by lithium is the beta-subunit of the calmodulin-dependent protein kinase or a different protein which co-migrates with it is discussed.     

Ethanol-Induced Enhancement of Cocaine Bioactivation and Irreversible Protein Binding: Evidence Against a Role of Cytochrome P-450IIE1

Chronic ethanol consumption potentiates cocaine-induced liver injury in rodents. Since cocaine has to be bioactivated by a cytochrome P-450-dependent N-oxidative pathway to exert its hepatotoxic effects, we studied the role of the ethanol-inducible P-450IIE1 for cocaine metabolism. Male Sprague-Dawley rats were pretreated with either a liquid diet containing ethanol (30% of calories) for 4 weeks or injected with pyrazole (200 mg/kg/day, ip, for 3 days). Both agents induced microsomal p-nitrophenol hydroxylation which is a probe for the catalytic activity of P-450IIE1. However, only ethanol, but not pyrazole, increased both microsomal cocaine N-demethylase activity (by 47%) and the extent of irreversible binding of [3H]-cocaine to microsomal proteins (by 100%), which was taken as a quantitative endpoint for the formation of a reactive metabolite. Cocaine N-demethylation and irreversible protein binding of cocaine were not inhibited by P-450IIE1 isozyme-selective substrates, nor was the rate of cocaine metabolism and binding decreased by functionally active polyclonal anti-rat P-450IIE1 antibodies. Furthermore, pyrazole pretreatment sensitized cultured hepatocytes to the glutathione-dependent cytotoxic effects of nontoxic concentrations of cocaine. These results indicate that (a) cocaine is not a major substrate for the ethanol-inducible P-450IIE1, (b) the enhancing effects of ethanol on cocaine bioactivation may be due to induction of other P-450 isoforms, and (c) induction of P-450IIE1 may potentiate cocaine-induced hepatocellular toxicity in vitro independently of cocaine metabolism, e.g., by P-450IIE1-dependent oxidative stress.     

蛋白芯片检测系统(多肿瘤标志物C12系统)的应用评价

目的：应用并评价蛋白芯片检测系统(多肿瘤标志物C12)的临床价值。方法：应用雅培电化学发光系统(ECL)和C12系统双盲法检测41份血清标本。结果：在对照检测达10份标本的AFP、CEA、β-HCG三个项目，C12系统和ECL系统符合性达81．8％以上；C12系统多个指标间可相互支持其准确性，并有助于判断肿瘤来源。结论：C12系统具有较高准确性，其指标间可相互支持，并有助于判断肿瘤源性。     

人T淋巴母细胞（Jurkat）移动性的研究

利用人Ｔ淋巴母细胞（Ｊｕｒｋａｔ）细胞系作为研究对象。企图探探索细胞外基质成份及肌醇磷脂细胞信息传递系统与细胞移动的关系。研究结果表明：当细胞被伏波醇酯（ＰＭＡ）处理过后，其粘连性与移动件对纤维连结蛋白（ＦＮ）底物的反应在已是高水平的基础上有更进一步提高的作用。与ＦＮ刊相反的是，未经ＰＭＡ处理处的Ｊｕｒｋａｔ细胞对层粘连蛋白（Ｌｍ）底物却无明显的粘连性及移动性增加的反应，尽管在ＰＭＡ处理过４小时内亦无任何的增强。但是，当ＰＭＡ作用于细胞２４一４８小时后则明显池增加其Ｌｍ底物的粘连性及移动性反应，表明了其明显的协同作用。分别用抗ＦＮ、抗Ｌｍ及蛋白激酶Ｃ抑制剂Ｓｔａｕｒｏｓｐｒｉｎｅ（ＳＰ）时均起到特异性的抑制作用。可见，协同作用的产生是通过蛋白激酶Ｃ激活后的－段时间内，使细胞表面Ｌｍ受体密度增加而对底物Ｌｍ反应增强所致。     

膳食纤维与不同蛋白质联用对大鼠胆固醇代谢的影响

观察４种膳食纤维在两种蛋白来源下，对高脂血症大鼠生长、血脂、肝胆固醇、粪类固醇及胆汁成分的影响。结果表明：①四种膳食纤维均可降低大鼠血清ＴＣ水平，尤以豆胶效果显著。②豆胶显著升高ＨＤＬ－Ｃ／ＬＤＬ－Ｃ。膳食蛋白为大豆蛋白时，豆胶、沙棘皮可显著升高血清ＨＤＬ－Ｃ、ＨＤＬ－Ｃ／ＴＣ。③豆胶显著减少肝胆固醇累积，两种沙棘皮与大豆蛋白联用降脂强于与酪蛋白共用。④蛋白来源显著影响粪类固醇的排出，纤维类型可影响中性固醇排出并与蛋白质有交互作用。提示：蛋白质与膳食纤维之间的交互作用是探讨营养素与脂质代谢不可忽视的因素。     

Fibrinogen promotes monocyte adhesion via a protein kinase C dependent mechanism

The accumulation of blood monocytes at sites of predilection of the vessel wall is an early cellular event of atherogenesis. Proteins of the vessel wall may facilitate monocyte adhesion and thus promote their recruitment. It has been shown that the relative content of extracellular fibrinogen increases during lesion development, and this study investigated the contribution of immobilized fibrinogen to monocyte adhesion and the underlying mechanism. Freshly isolated human blood monocytes were cultivated in serum-free RPMI 1640 in tissue culture wells precoated with albumin, fibrinogen, or fibrin. After 16 h the plates were washed and adherent cells enumcrated. Immobilized fibrinogen enhanced monocyte adhesion more than 1.9-fold compared to immobilized albumin or fibrin (P<0.05). Concomitant addition of the protein kinase C (PKC) inhibitors staurosporine or H7 suppressed monocyte adherence to immobilized fibrinogen but exerted no significant effect upon adhesion to any other surface tested. Stimulation of monocytes using phorbol myristate acetate resulted in increased binding of monocytes on fibrinogen but not on bovine serum albumin. When PKC activity was reduced through prolonged incubation with PMA for 16h, a significant reduction of monocyte adhesion on fibrinogen was observed. Peptides containing RGD sequences, which have been demonstrated to be ligands for certain integrins, did not inhibit monocyte adhesion. The data suggest that fibrinogen promotes monocyte adhesion in vitro by a PKC-dependent mechanism. PKC appears to be important not only for the initial cell adhesion but also for sustained binding of monocytes to fibrinogen.Abbreviations BSA Bovine serum albumin - ECM Extracellular matrix - PKC Protein kinase C - PMA Phorbol myristate acetate     

环磷酰胺冲击与小剂量持续应用对大鼠性激素影响的比较研究

Wistar大鼠随机分3组，每天组予环磷酰胺组（CP）8mg／kg·d×4W，ip；冲击组予CP56mg／kg·d×4W，ip；对照组予生理盐水1ml／d×4W，ip。结果：①睾丸生精细胞损伤：每日组重于冲击组；②血睾酮（T）含量每日组显著低于冲击组（P＜0．05）；冲击组与对照组无显著差异（P＞0．05）。③对睾丸间质细胞的影响：冲击组轻于每日组；④血FSH、LH含量与垂体重量：每日组与冲击组皆正常；⑤血BUN、Cr水平：3组皆正常．说明CP冲击疗法对睾丸间质细胞损伤较轻；CP除直接损伤睾丸组织外，可能还对下丘脑—垂体—睾丸轴有抑制作用．     

Stimulation of spontaneous transmitter release at the frog neuromuscular junction by 12-O-tetradecanoylphorbol-13-acetate occurs in the absence of extracellular Ca2+ and is enhanced by depolarization

Summary The effect of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) on the release of transmitter at the frog neuromuscular junction has been investigated electrophysiologically. TPA (100 nmol/l) caused a gradual rise in miniature end-plate potential (MEPP) frequency. After 20–30 min MEPP frequency had risen by approximately 40%. This action of the drug was not inhibited by bathing preparations in either Ca²⁺-free medium (0 Ca²⁺-1 mmol/l EGTA) or high Mg²⁺ medium, or by pretreatment with verapamil (5 mol/l). The inactive TPA analogue 4--TPA had no effect on release rate. There was no indication of any positive correlation between resting MEPP frequency and the size of the subsequent response to TPA treatment. Any synergism between [Ca²⁺]_i and TPA treatment is therefore likely to occur at a site other than that which determines spontaneous release rate.The stimulatory effect of TPA was enhanced 2-fold by carrying out the experiments in a partially depolarising saline (10 mmol/l K⁺). When TPA was applied to preparations bathed in Ca²⁺-free depolarising saline, the response to the drug was still significantly greater than that in non-depolarised preparations. It is concluded that responsiveness to TPA is enhanced by depolarisation, but that little, if any, of this enhancement can be attributed to the consequent influx of Ca²⁺.Send offprint requests to S. J. Publicover at the above addressPEL was in receipt of an S.E.R.C. postgraduate awardZYS was in receipt of financial support from Umm Al Qura University, Saudi Arabia