The Inheritance of human erythrocyte catechol-O-methyltransferase activity

Erythrocyte catechol-O-methyltransferase (COMT) activity was analyzed in 107 individuals from 23 families. The observed activities were consistent with an autosomal codominant inheritance of the gene coding for erythrocyte COMT activity.     

The ring-infected erythrocyte surface antigen of Plasmodium falciparum associates with spectrin in the erythrocyte membrane.

The malaria parasite Plasmodium falciparum synthesises a protein, RESA, which associates with the membrane of newly invaded erythrocytes. Using spent supernatants from P. falciparum growing in culture as a source of soluble RESA we have developed an assay to examine the characteristics of RESA binding to the erythrocyte membrane in vitro. RESA associated with the Triton X-100 insoluble proteins on the inner face of the host erythrocyte membrane but did not bind to the outer surface of intact erythrocytes. Other proteins present in culture supernatants did not bind to the erythrocyte membrane. RESA was co-sedimented with the ternary complex formed between actin, spectrin and band 4.1 and co-precipitated with spectrin precipitated with anti-spectrin antibodies. The extent of association between RESA and the inner face of the erythrocyte membrane was reduced by the inclusion of excess purified spectrin in the assay. Thus, RESA appears to be associated with spectrin in the erythrocyte membrane skeleton.     

SARS患者红细胞天然免疫黏附功能变化的探讨

目的研究SARS患者红细胞天然免疫黏附功能(erythrocyte卫生innate immunea dhesion function，EIIAF)的变化及与红细胞CRl数量、循环补体C3、C4及免疫复合物含量等变化之间的关系，探讨引起EIIAF变化的可能原因。方法EIIAF检测：将100μl枸橼酸钠抗凝的待测病人血浆和1μm离心沉淀红细胞，直接加到150μl定量分装的靶细胞管中，充分混匀，37℃水浴30min，结合5个或以上红细胞的靶细胞为1个黏附单位，计算黏附率。正常人血浆和红细胞与病人红细胞和血浆互换试验：洗涤病人红细胞，与正常人血浆进行EIIAF检测，同时将正常人红细胞与病人血浆进行EIIAF检测作为对照。红细胞补体Ⅰ型受体(CRl)定量测定：采用细胞酶免法。补体C3、C4含量，采用免疫比浊法测定。循环免疫复合物采用凝集法。结果65例SARS患者在出现发热等临床症状1～3d内EIIAF即不同程度地下降，EIIAF的下降程度与患者发热、全身中毒症状及肺部炎症渗出的程度密切相关。重症SARS和因呼吸窘迫综合症死亡的患者其EIIAF接近完全消失；肺部阴影全部吸收时EIIAF回升到正常水平，并一过性地高于自身正常水平，然后再有不同程度的下降。正常人红细胞在SARS病人血浆中的EIIAF明显受到抑制，病人红细胞在正常人血浆中的EIIAF无明显回升。重症SARS患者的红细胞CRl数量显著下降，与EIIAF的变化密切相关，CRl数量下降程度较轻的患者病情较轻且恢复较快，3例隐性感染的SARS病例其红细胞CRl数量表达全部处于高水平。SARS患者补体C3、C4在疾病早期处于正常水平，在发病第2周明显下降，第3周即回升，与EIIAF平行。循环补体免疫复合物的含量随病情恢复而下降，与EIIAF密切相关。结论SARS患者EIIAF的降低，可能是红细胞参与补体介导的免疫清除过程中其表面的CRl被消耗所致；血浆中可能存在免疫反应性产物对EIIAF具有抑制作用。免疫损伤和免疫清除的相互消长，可能是影响SARS病情发展的重要因素之一。     

The effects of ultracentrifugation on the mammalian erythrocyte

Pieces of rat spleen were subjected in an air turbine ultracentrifuge to a force of approximately 400,000 times gravity for periods varying from one-half to one hour. They were immediately fixed for study with both the light and electron microscopes. Stained preparations show a displacement and stratification of materials within the erythrocytes. The stratified layers are probably components of the stroma which differ in their relative specific gravities and staining reactions. The chemical nature of the different layers has not been determined, but their relative volumes are indicated by the dimensions of the layers. Electron micrographs show some effects of the ultracentrifugation such as stretching and the concentration of more dense material in the centrifugal halves of the cells, but a clear cut demonstration of the three stratified layers observed in Mallory's triple stained preparations is not evident. Except for the plasma membrane and a finely granular interior of the erythrocyte, little other structure is revealed within it, especially concerning the nature and distribution of the stroma.     

The erythrocyte sedimentation rate in congestive heart failure

BACKGROUND AND METHODS. Physicians have long believed that the erythrocyte sedimentation rate is low in patients with congestive heart failure, but this concept is based on a misinterpretation of the results in a single report published in 1936. To reevaluate this concept in the modern era, we measured the sedimentation rate in 242 patients who were referred for treatment of chronic heart failure. RESULTS. The sedimentation rate was low (less than 5 mm per hour) in only 24 patients (10 percent) but was increased (above 25 mm per hour) in 50 percent. Patients with low or normal sedimentation rates (less than or equal to 25 mm per hour) had more severe hemodynamic abnormalities than patients with elevated rates: lower cardiac index (mean +/- SEM, 1.7 +/- 0.1 vs. 2.0 +/- 0.1 liters per minute per square meter of body-surface area) and higher mean right atrial pressure (mean +/- SEM, 12 +/- 1 vs. 9 +/- 1 mm Hg) (both P less than 0.0001). New York Heart Association functional class IV symptoms were present in 66 percent of the patients with a low or normal sedimentation rate, as compared with 42 percent of those with elevated rates (P less than 0.0001). After one to three months of therapy, patients whose sedimentation rates decreased showed little hemodynamic or clinical response to treatment, whereas both cardiac performance and functional status improved in patients whose rates increased (P less than 0.02 for the comparison between groups). The sedimentation rate was correlated with the plasma fibrinogen level (r = 0.64, P = 0.0025), and changes in the sedimentation rate during treatment were correlated inversely with changes in mean right atrial pressure (r = -0.57, P = 0.0002). During long-term follow-up, patients with low or normal sedimentation rates had a worse one-year survival than patients with elevated rates (41 vs. 66 percent, P = 0.01). CONCLUSIONS. These data indicate that the erythrocyte sedimentation rate is correlated with the severity of illness in patients with chronic heart failure. Because of its lack of discriminatory power, however, the test is of limited value in the clinical management of this disorder.     

The effect of adrenal steroids on human erythrocyte phosphofructokinase

Phosphofructokinase isolated from human erythrocytes incubated with cortisol showed alterations in regulatory properties. The enzyme was more sensitive to the inhibition by ATP and citrate. This effect was abolished by alanine. Similar changes in phosphofructokinase properties were found after incubation with aldosterone and corticosterone.     

红细胞硬化对取向和变形的影响

戊二醛是一种常用的固化剂，对细胞膜有良好的固化作用。本文报道了红细胞被戊二醛不同程度的固化后，红细胞在切变流场中C＝0轨道的取向指数和高粘介质中变形指数的变化情况。结果发现：红细胞硬化后，变形指数和取向指数都随硬化程度增加而呈现出逐渐下降的趋势。在切变率为150s^-1条件下，变形指数的改变不显著，而取向指数下降很显著。这个现象表明：在该条件下，红细胞取向指数对红细胞膜的硬化较敏感，红细胞变形指数对红细胞膜的变化和流变环境恶化的改变不是很敏感。     

The activity of erythrocyte glutathione peroxidase in chronic renal failure

Summary In 18 patients with terminal chronic renal failure on twice weekly maintenance hemodialysis, the predialysis activity of glutathione peroxidase was not impaired but rather slightly but significantly elevated when compared with healthy controls (2.7 versus 2.1 units/p<0.01). This was attributed to the reduced mean cell age.     

The association between erythrocyte internal viscosity, protein non-enzymatic glycosylation and erythrocyte membrane dynamic properties in juvenile diabetes mellitus.

The association of intracellular viscosity of red blood cells and the dynamic properties of erythrocyte membranes in children suffering from diabetes has been investigated by means of ESR spectroscopy. It has been revealed that the slight decrease in the ratio hw/hs of maleimide bound to membrane protein-SH groups of erythrocytes in diabetes may ensue from the enhanced membrane protein immobilization in the plane of lipid bilayer. These alterations were accompanied by a corresponding increase in the relative rotational correlation time (tau c) of iodoacetamide spin label, thus suggesting that the conformational changes in membrane proteins may occur at both the intrinsic and more exposed thiol groups. The membranes of diabetic red blood cells were more glycosylated than those of relevant controls, and the extent of glycosylation was found to correlate significantly with h + 1/h0 and tau c (r = -0.652, P < 0.01 and r = 0.609, P < 0.01). Further, the conformational alterations in erythrocyte membranes from diabetic subjects were accompanied by a significant increase in the mobility parameter (h + 1/h0) of haemoglobin molecules in diabetic erythrocytes. The latter changes correlated well with the enhanced intracellular viscosity of diabetic red blood cells and the level of glycosylated haemoglobin. We conclude that the alterations in membrane lipid-protein interactions together with the increased glycosylation-derived internal viscosity may consequently imply altered viscoelastic properties of erythrocyte membranes and, underlying the impaired deformability of red blood cells in the diabetic state, contribute to the development of late diabetic sequelae.