大肠杆菌脂多糖对人红细胞蛋白激酶C活性的影响

正常成人红细胞与大肠杆菌脂多糖温育后,胞膜蛋白激酶C活性显著增加,脂多糖这种作用呈现剂量和时间依赖性。结果提示脂多糖能激活红细胞蛋白激酶C。     

青蒿琥酯钠对体外大鼠红细胞膜钠-钾交换ATP酶的抑制

体外测定青蒿琥酯钠(SA)对大鼠红细胞膜Na~( )-K~( )-交换ATP酶活性的影响.方法:在反应系统中分别加入不同浓度的SA(0,0.5,1,5和10 μmol·L~(-1)),通过测定反应系统中释放的无机磷含量,计算酶活性.结果:随着SA浓度(O,0.5,1,5和10 μmol·L~(-1))的增高,对Na~( )-K~( )-交换ATP酶活性的抑制作用也随之增强,抑制率分别为15％,29％,46％和75％.将底物ATP浓度增加为125,250,375和500 μmol·L~(-1),进行了酶的动力学测定.用直线回归分析作Eadie-Hofstee动力学曲线,结果表明,SA对该酶的抑制作用为竞争性抑制.结论:提示SA可影响宿主红细胞膜的离子转运及膜的功能.     

甘糖酯和胰岛素对体外孵育红细胞变形性的影响

目的：观察甘糖酯及胰岛素对体外孵育红细胞变形性（ＥＤ）的影响。方法：对１２例ＩＩ型糖尿病（ＮＩＤＤＭ）病人（男性６例，女性６例，年龄６０±ｓ１０ａ）取血观察其ＥＤ，并与正常人比较。将红细胞分别与甘糖酯和胰岛素共同孵育２４ｈ观察ＥＤ变化。结果：病人的ＥＤ明显低于正常人。孵育２４ｈ后，ＥＤ进一步降低。但与甘糖酯孵育后ＥＤ较孵育前改善。与胰岛素共同孵育后，ＥＤ较孵育前降低，但较不加药物孵育者降低程度小。结论：甘糖酯在体外可使ＮＩＤＤＭ病人ＥＤ改善。胰岛素的作用较弱。     

Role of hemoglobin in regulation of membrane electrical properties and erythrocyte volume

Erytyrocyte volume in neonates is 25.8% greater than in women. Electrophoretic erythrocyte mobility was the same in neonates and in parturient women. The results obtained indicate that the more heterogeneous the hemoglobin system, the more heterogenous are erythrocyte membrane electrical characteristics. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 7, pp. 49–51, July, 1998     

Usefulness of erythrocyte protoporphyrin as a primary screening test for lead exposure in children

Erythrocyte protoporphyrin and blood lead concentrations were measured in samples from 583 Saudi children attending the outpatient clinics. Erythrocyte protoporphyrin concentrations showed poor correlation with blood lead concentrations of 25 ug dl^?1 and below. Measurement of erythrocyte protoporphyrin as a primary test for lead exposure is not recommended.     

丁卡因对人红细胞膜乙酰胆碱酯酶的抑制作用及其与膜脂的关系

本文以人红细胞膜为材料，应用荧光探针（ANS）及酶学研究方法，研究了丁卡因对AchE及红细胞膜脂之间的关系。结果显示，丁卡因对红细胞膜AchE有明显抑制作用，其半数抑制浓度为525μmol/L。丁卡因还能増加膜-ANS复合物荧光强度，双倒数及Scatchard作图分析表明，其使膜ANS复合物荧光强度增强的原因并非ANS荧光量子产率的改变，而是膜上ANS结合数量增加所致，这一效应与其时膜流动性影响是一致的。     

A single gene copy merozoite surface antigen and immune evasion?

During the course of chronic malaria infection antigenic variants of a parasite antigen are expressed and exposed on the surface of infected erythrocyte membranes. There also exists a number of apparently invariant single gene copy blood-stage antigens, exposed or non-exposed, which have been shown to afford immunity under experimental conditions. To determine why the host, presented with invariant 'protective' antigens, is unable to control infections effectively, immunity to a representative single gene copy antigen, the merozoite surface protein 1 (MSP1) was investigated in Plasmodium chabaudi chabaudi AS, a murine model of chronic malaria. Immunization with monoclonal antibody affinity purified native MSP1 resulted in enhanced control of parasitaemia on challenge, irrespective of the parasite inoculum size; challenge with a single parasite, however, suggested that expansion of resistant parasite subpopulations was not occurring. Challenge of mice immunized with recombinant fusion proteins encoding N- or C-terminal regions of the P.c. chabaudi AS MSP1 produced inconsistent effects, often parasitaemias were indistingishable from controls despite significant anti-MSP1 antibody responses. The not unlikely contamination of MSP1 native preparations with erythrocyte (E) components was considered. Immunization with a mixture of the MSP1 C-terminus recombinant polypeptide and a Triton X-100 solubilized lysate of normal E resulted in enhanced control of parasitaemia, however, no effect was seen after administration of either component on its own. Co-immunization of E with the N-terminus polypeptide reversed the inhibition seen, on this occasion with this construct alone.     

慢性肺心病红细胞变形性与红细胞膜流动性变化（附17例病例分析）

用荧光偏振法测定17例慢性肺心病急性发作期患者及17名健康人红细胞膜流动性,用微孔泸膜法测定其中10例红细胞变形性。结果,肺心病患者及正常人红细胞膜微粘度分别为4.64±1.56及3.51±1.05η(p<0.05);红细胞滤速分别为384±136及233±97(p<0.01)。红细胞滤速与红细胞膜粘度间呈明显正相关(r=0.802,p<0.01)。结果提示,肺心病患者红细胞膜流动性下降可能对红细胞变形性下降起一定作用。     

Humoral and cellular effects of the K+-channel activator cromakalim in man

Summary The effect of cromakalim, a K⁺-channel activator, on the plasma renin-angiotensin-aldosterone system, catecholamines and -atrial natriuretic peptide, and on the intraerythrocyte concentration and transmembrane fluxes of Na⁺ and K⁺ has been investigated in 18 normal male subjects, in a double-blind parallel study. After a run-in period on placebo for 1 week, the subjects were treated either with placebo (n=6) or cromakalim (n=12) for 1 week.Plasma renin activity was significantly increased during cromakalim. No effect of cromakalim on plasma angiotensin II, aldosterone, adrenaline, noradrenaline and -atrial natriuretic peptide was demonstrated. The intra-erythrocyte K⁺ concentration was decreased during cromakalim administration and Ca²⁺-dependent K⁺-channels in red blood cells were increased.