脂肪乳剂对食管癌术后细胞因子和免疫功能的影响

目的：本研究探讨脂肪乳剂对食管癌术后炎症反应和免疫功能的影响。方法：采用前瞻性、随机、对照设计，将33例食管癌切除术病人随机分成2组，A组(15例)为对照组接受不含脂肪乳剂的肠外营养，B组(18例)接受含有脂肪乳剂的肠外营养。2组病人的一般临床情况、非蛋白热量分布一致。分别于术前术后不同时段测定血清中IL—6、IL—10浓度、T细胞亚群和NK细胞活性。结果：术后1、3天两组血清IL—6水平均显升高，且B组显高于A组。血清IL—10与IL—6变化相似。术后3天血清IL-6浓度与IL—10浓度显正相关。术后血清IL—6／IL—10比值显升高，术后7天B组显高于A组。术后CD4^ /CD8^ ,NK细胞活性均显降低，术后10天B组CD4^ /CD8^ 比值显低于A组。术后3天CD4^ /CD8^ 比值与术后1天IL—6水平显正相关。结论：高应激病人输注脂肪乳剂能增加细胞因子产生并促进免疫抑制。     

A novel missense mutation (Asn5→Ile) in lecithin: cholesterol acyltransferase (LCAT) gene in a Japanese patient with LCAT deficiency

We identified a novel missense mutation in the lecithin: cholesterol acyltransferase gene in a new case of lecithin:cholesterol acyltransferase (LCAT) deficiency. The patient was a 64-year-old diabetic Japanese male who showed an extremely low level of serum high-density lipoprotein-cholesterol, corneal opacities, anemia, and proteinuria. Both the patient's LCAT activity and mass were markedly low. DNA sequence analysis of the LCAT gene showed an A-to-T transition at base 97 in exon 1, and predicted a change in asparagine to isoleucine at the 5th amino acid of the protein. Restriction analysis of polymerase chain reaction-amplified DNA usingAse I showed that the patient was homozygous for this mutation. Our results suggested that asparagine 5 was an important amino acid and substitution with isoleucine caused marked reduction of LCAT activity and mass, resulting in LCAT deficiency.     

大豆超氧化物歧化酶的分离和鉴定

采用磷酸盐缓冲液使样品匀浆,两次硫酸铵分级沉淀和DEAE-Cellulose离子交换层析从大豆中分离出超氧化物歧化酶。分离酶的聚丙烯酰胺凝胶电泳呈一条蛋白谱带。过氧化氢和乙醇-氯仿试验表明,该酶属铜锌超氧化物歧化酶。酶的比活力为4710u/mg Pr,活力回收率23％,紫外吸收峰在265.4nm,分子量为32.4kD。     

大豆制品中胰蛋白酶抑制物活性测定方法的改进——多因素正交试验的应用尝试

本文对胰蛋白酶抑制物活性的测定方法进行了改进。应用多因素正交试验获得了最佳实验条件。最佳实验条件为样品提取液1ml(相当原样品1mg),胰蛋白酶用量4mg,保温时间为37℃15分钟。本文也探讨了胰蛋白酶与光密度的关系,并应用本文的条件和改进的方法对生豆粉和烘烤过的豆粉(150℃30分钟)中胰蛋白酶抑制物的活性进行了测定。     

Diazepam inhibits cholesterol esterification by arterial ACAT and plasma LCAT, in vitro

Benzodiazepine drugs have been reported to have antiatherosclerotic effects in rabbits and roosters and to alter the pattern of circulating lipoproteins in man. The mechanism(s) of these effects has not been elucidated. The studies presented here indicate that diazepam, the most widely used benzodiazepine, is an inhibitor of cholesterol esterification by ACAT in vitro in atheromatous rabbit aortas, in microsomes isolated from atheromatous rabbit aortas, and in normal rat aortas. Diazepam also inhibited LCAT in plasma from man, monkey, rabbit, and rat, in vitro. The ability of diazepam to inhibit these enzyme systems may offer insight into possible in vivo mechanisms of action against atherosclerosis and of lipoprotein modification.     

Dissolving intravenous cyclosporin A in a fat emulsion carrier prevents acute renal side effects in the rat

Cyclosporin A (CyA)-induced nephrotoxicity is still a serious clinical problem. The nephrotoxicity seems to be more pronounced when CyA (solubilized in water with Cremophore EL, as in Sandimmun) is given intravenously than when it is given orally. Using soybean oil in which CyA was dissolved, we prepared an intravenous fat emulsion without an artificial detergent, such as Cremophore EL. The renal effects of our new formula were compared with those of Sandimmun and Cremophore EL in a rat model. CyA in the fat emulsion did not significantly affect the glomerular filtration rate (GFR). Both Sandimmun and Cremophore EL significantly reduced the GFR. These results suggest that a change in the vehicle may obviate the acute nephrotoxic side effects caused by intravenous administration of CyA solubilized by Cremophore EL.     

Formulation,Characterization, and In Vitro Evaluation of Silymarin-Loaded Lipid Microspheres

The objective of our study was to incorporate and evaluate Silymarin, a chemically defined natural hepatoprotective agent, in lipid microstructured systems. Various constituents of lipid microspheres—namely, internal oily core; surfactant such as soyabean lecithin; and cosurfactants such as span 20, tween 20, tween 80, and propylene glycol—were tried in different concentrations to optimize the final formulation characteristics such as globule size range, structural integrity, sustainability, and percent drug-holding capacity. The final formulation (formulation A) was characterized with respect to size and morphology using transmission electron microscopy and laser diffraction technique. The enhanced mean percent release of 56.70 ± 2.03% was observed in 36 hr from silymarin-loaded lipid microspheres (formulation A), as compared to 18.67 ± 0.192% with silymarin solution (formulation B). Thus, a stable delivery system having synergistic hepatoprotective effect of silymarin and soyabean lecithin could successively be produced for passive targeting to the liver.     

Insecticide toxicity to Hyalella curvispina in runoff and stream water within a soybean farm (Buenos Aires, Argentina)

Toxicity to the locally dominant amphipod Hyalella curvispina was assessed in a first-order stream running through a cultivated farm. Cypermethrin, chlorpyrifos, endosulfan and glyphosate were sprayed throughout the studied period. Toxicity was assayed under controlled laboratory conditions with runoff and stream water samples taken from the field under steady state and flood conditions. Ephemeral toxicity pulses were observed as a consequence of farm pesticide applications. After pesticide application, runoff water showed 100% mortality to H. curvispina for 1 month, but no mortality thereafter. Toxicity persistence was shortest in stream water, intermediate in stream sediments and longest in soil samples. Runoff had a more important toxicity effect than the exposure to direct aerial fumigation. The regional environmental features determining fast toxicity dissipation are discussed.