等容血液稀释对大鼠局灶性脑缺血作用的研究

以血液稀释治疗血栓栓塞性脑缺血为目的,采用大脑皮层局部血流量(rCBF)、脑组织含水总量以及脂质过氧化物含量(LPO)为重要指标,共71只大鼠的实验研究,结果表明:大脑局灶性缺血24小时后经血液稀释治疗2小时,血细胞压积由49.4±3.5%降至39.3±3.77%,rCBF增加19.95%(n=16,P<0.005),脑组织含水量及LPO含量,对照组与稀释组分别为81.39±1.56%(n=12),79.00±1.08%(n=13,P<0.001);645.57±106.72nmol/100mgpro(n=11),360.47±117.46nmol/100mgpro,(n=14,P<0.001)。提出血液稀释可增加rCBF,减轻脑水肿,降低LPO。     

Experimental studies of membrane tethers formed from human neutrophils

Membrane tethers (thin, cylindrical pieces of membrane) have been implicated in the rolling of neutrophils along the endothelium. In our studies, these tethers were formed from passive, stimulated (0.1 M fMLP), and osmotically swollen (170–180 mOsm) human neutrophils; as well as neutrophils treated with 0.3 M latrunculin A to disrupt the cytoskeleton. This tether formation was accomplished by micropipette suction of latex beads coated with antibodies to proteins on the neutrophil membrane surface. From plots of force versus velocity for the tether formation process, we calculated adhesion energies per unit area of the lipid membrane to the cytoskeleton and the viscous resistance (effective viscosity) that occurs during the formation of these tethers at finite velocity. Most of the properties of the neutrophil were altered once it had been treated as described above. We were also able to show mechanical reversibility of membrane tethers, as well as an unexpected formation rate at high tether forces. Since membrane tethers have been implicated in the rolling of neutrophils, then the changes in tether formation may ultimately alter how these cells roll. © 2002 Biomedical Engineering Society. PAC2002: 8716Dg     

振动对动物体内血脂水平的影响

为了研究振动对生物体内物质的耗散作用，本文在振动频率为２０Ｈｚ，振幅为０．１ｃｍ条件下对土母鸡的腹部脂肪作局部振动。并于振动一个疗程（２小时／天，５－７ｘ）的前后分别测试了血清中总胆固醇（ＴＣ）、甘油三脂（ＴＧ）和高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）等各项指标。结果表明：上述特定频率、振幅与时间的振动使实验动物体内血清中总胆固醇、高密度脂蛋白胆固时与低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）显著增加；甘油三酯显著减少（Ｐ＜０．０５）。ＴＣ的变化与ＨＤＬ－Ｃ、ＬＤＬ－Ｃ的变化呈正相关；ＴＧ的变化与ＨＤＬ－Ｃ的变化呈负相关。从而证实了特定参数的振动对动物体内的脂肪代谢有明显的作用，为人体施局部伍振动减肥的可行性提供了有益的参考。     

Investigation of the renal injury caused by liver ischemia-reperfusion in rats

To explain the mechanism of renal injury caused by liver ischemia-reperfusion, we investigated biochemical and morphological changes in the liver and kidney in rats. After reperfusion following 60 min of liver ischemia, numerous changes were found. The level of serum transaminases and lipid peroxide formation in the liver tissue increased significantly. Electron microscopic studies revealed that most of the hepatocytes had swollen mitochondria and clumping of the nuclear chromatin. The sinusoidal endothelium was disrupted and the sinusoidal lumen was filled with numerous erythrocytes. Blood endotoxin concentration, plasma lipid peroxide levels, and serum -glucuronidase activities were significantly higher than in the control group. Biochemical and morphological renal injury was also observed. Tissue lipid peroxide levels increased in both the kidney and the liver. Microscopic examination revealed damage to the renal tubules, including interstitial edema, dilatation of the lumen, and granular casts derived from necrotic cells in the proximal convoluted tubule. The levels of urinary N-acetyl--d-glucosaminidase (NAG) in the liver ischemia-reperfusion group were also higher than in the control group. These results suggest that the renal injury was caused by an increase in endotoxin, lipid peroxide, and lysosomal enzymes in the blood following the liver injury induced by the ischemia-reperfusion.     

实验性矽肺支气管肺泡灌洗液及血清中脂质过氧化物含量的动态变化

本文对实验性矽肺大鼠支气管肺泡洗液(BALF)和血清中脂质过氧化物(LPO)含量进行动态观察。对矽肺发病机理进行初步探讨。实验结果表明:不同染尘时间矽肺大鼠,在BALF和血清中LPO的含量均高于对照组。差别有显著或非常显著性(P<0.05或P<0.01)。提示SiO_2能诱发肺组织产生大量自由基,细胞或细胞膜的脂质过氧化反应引起细胞的破坏,崩解,最终导致矽肺病变的发生和发展。     

Effect of the peroxisome proliferator perfluorodecanoic acid on growth and lipid metabolism in Sprague Dawley rats fed three dietary levels of selenium

The possible interrelationships between the effects of dietary selenium and perfluorodecanoic acid (PFDA) on growth and lipid metabolism were studied in the male Sprague Dawley rat. Rats were divided into groups and placed on diets containing three levels of selenium (0.04, 0.2, and 1.0 ppm as sodium selenite). Two weeks later, half the rats in each group received a single 35 mg/kg IP injection of PFDA in corn oil, while their pair-fed companion received only vehicle. Rats injected with PFDA stopped gaining weight, and weighed less than pair-fed controls, despite equal food intakes. Two weeks following PFDA administration the rats were killed and plasma cholesterol and triglycerides, and liver peroxisomal enzyme activities were quantified. In contrast to other peroxisome proliferators, PFDA increased plasma triglycerides while decreasing plasma cholesterol. The rate of peroxisomal fatty acid -oxidation was decreased, even though the activity of fatty acyl-CoA oxidase, the first enzyme in the peroxisomal fatty acid -oxidation pathway, was increased. Dietary selenium, other than increasing the liver to body weight ratio, did not alter growth or lipid metabolism. This study demonstrates, for the first time, the existence of a non-hypotriglyceridemic peroxisome proliferator-PFDA.     

参麦注射液对阿霉素中毒心肌细胞脂质过氧化和钙超载的影响

目的：应用阿霉素（ADR）复制新生大鼠心肌细胞中毒模型,观察参麦注射液（SMI）对中毒心肌细胞的保护作用并探讨其机制,方法：将培养72h以后的新生大鼠心肌细胞分为对照组,模型组和SMI保护组,继续培养24h后测定培养基中乳酸脱氢酶（LDH）释放量,细胞内丙二醛（MDA）含量,超氧化物歧化酶（SOD）活力以及细胞内游离钙离子浓度（[Ca^2 ]i)。结果：SMI能够减少ADR中毒心肌细胞LDH释放量,降低细胞内MDA含量和[Ca^2 ]i,同时增强细胞内SOD活力。续集：SMI能够对抗自由基引起的脂质过氧化和逆转细胞内钙超载,从而保护ADR中毒心肌细胞。     

诊断超声对人胚胎安全性的研究

目的　探讨诊断级B超对人胚胎发育的安全性。方法　取 12 0名孕 6～ 8周拟行人工流产孕妇 ,随机分成正常对照组 (Ⅰ组 )、辐照 5min(Ⅱ组 )、10min(Ⅲ组 )、2 0min(Ⅳ组 )、30min(Ⅴ组 )于 1h内取绒毛 ,超声辐照 30min(Ⅵ组 )于 7～ 10d后取绒毛。检测绒毛的生物化学变化。结果　诊断剂量超声辐照 2 0min可致人体宫内绒毛发生生物化学变化。丙二醛 (MDA)值随超声剂量增加而升高 (PⅠ -Ⅲ >0 .0 5,PⅠ .Ⅳ <0 .0 1,PⅠ -Ⅴ <0 .0 1) ,而超氧化物歧化酶及谷胱甘肽过氧化物酶活性随超声辐照剂量增加而下降 (PⅠ -Ⅲ >0 .0 5,PⅠ -Ⅳ <0 .0 1,PⅠ -Ⅴ <0 .0 1)。对照组与Ⅵ组比较P >0 .0 5,提示损伤作用是可逆性的。结论　诊断超声辐照时间 2 0min以上时对绒毛可造成潜在危害