维生素E对IL-6作用的视网膜色素上皮细胞增生及胶原合成的影响

目的 探讨白细胞介素-6(IL-6)对视网膜色素上皮(RPE)细胞增生及胶原合成的作用，以及维生素E对这种作用的影响。方法 采用放射自显影的方法测定RPE细胞增生和胶原合成。用含IL-6和不同浓度维生素E的EMDM培养基培养RPE细胞，加入氚标记的胸腺嘧啶核苷(^3H-TdR)和氚标记的脯氩酸(^3H-proline)，测定每分钟闪烁值cpm，反映^3H-TdR和^3H-proline的掺入量，即RPE细胞增殖和胶原合成情况。结果 IL-6与RPE细胞共同孵育后，^3H-TdR和^3H-proline的掺入量较单纯RPE细胞培养组明显升高，提示IL-6促进RPE细胞增牛明显，胶原合成显著增加：不同浓度的维生素E和IL-6共同培养的RPE细胞^3H-TdR和^3H-proline的掺入量较单纯IL-6培养的RPE细胞组明显降低。且维生素E浓度越高，^3H-TdR和^3H-proline的掺入量越低，提示维生素E抑制IL-6引起的RPE细胞的增生和胶原合成，且抑制作用随浓度的增加而增加。结论 IL-6对RPE细胞的增生和胶原合成有促进作用，维生素E抑制IL-6引起的RPE细胞的增生和胶原合成，抑制作用与维生素E浓度成正比。     

马齿苋红花色素的提取及稳定性研究

目的 研究中草药马齿苋红花色素的提取方法及稳定性，为开发利用天然色素提供实验依据。方法 室温下，用酸性乙醇浸泡新鲜马齿苋红花，过滤得色素提取液，然后对该色素的耐酸碱性、耐热性、耐光性、耐氧化还原性等理化性质进行测定和分析。结果 该色素为水溶性食用色素，其耐光性较好，酸性介质、氧化荆、还原剂、常用食品添加剂对色素的色泽无不良影响。结论 该色素是一种可广泛应用于食品、饮料等行业，且具有药用价值的天然植物色素。     

Lymphocytotoxic T lymphocytes in a patient with B-chronic lymphocytic leukemia and pure red cell aplasia

The peripheral blood T cells of a hypertransfused patient with B-chronic lymphocytic leukemia and pure red cell aplasic were found to exhibit unusual spontaneous cytotoxic activity in vitro. The patient's E-rosette positive cells were cytotoxic for K562 (cultured human crythroleukemia cells) and allogeneic B and T lymphocytes freshly isolated from the peripheral blood of normal and CLL donors. They failed to kill autologous B cells, erythroid progenitors present in allogeneic bone marrow, and a number of cultured human tumor cells (Malme, CAKI) even after prolonged (36 h) co-culture. Peripheral blood T cells isolated from normal controls, other CLL patients, and hypertransfused individuals (n=13) (lid not exhibit spontaneous lymphocytotoxic activity. Circulating cytotoxic T cells having the ability to kill freshly isolated allogeneic lymphocytes have, heretofore, not been reported in humans. Our findings suggest that among this patient's peripheral blood T cells, there exists a subpopulation of lymphocytotoxic cells that closely resemble cytotoxic T cells generated in vitro after priming with allogeneic target cells. Although the lymphocytotoxic cells could have been induced in this patient by previous HLA-mismatched transfusions, it is possible they may have arisen spontaneously and underly the patient's erythroblastopenic state.     

Deformability characteristics of sickle cells by microelastimetry

Deformability of normal and sickle erythrocytes was measured by means of micropipette elastimetry with determination of intrinsic membrane rigidity (P) and total cell deformability (Pt). In the elastimetric technique employed, negative pressure at the pipette tip was generated and measured continuously. Membrane rigidity is defined as the negative pressure, in mm H₂O, required to induce a hemispherical projection of the cell surface into the micropipette, and total cell deformability as the negative pressure required to aspirate the entire cell into the pipette lumen. Membrane rigidity for oxygenated sickle discocytes was not statistically different from that of control normal discocytes, but Pt measurements were significantly higher for sickle than normal discocytes. Irreversibly sickled cells (ISCs) had markedly increased membrane rigidity and whole cell deformability when compared to control normal cells. Mildly deformed ISCs and severely deformed ISCs at ambient pO₂, both showed significantly higher mean membrane rigidity values than sickle discocytes and reversibly sickled cells. Sickle and normal discocytes both showed membrane elasticity with reversion to original cell shape following release of the cell from its aspirated position at the pipette tip. ISCs, however, exhibited elastic deformation of the membrane. These studies provide further evidence of progressive alteration of the sickle cell membrane induced by the sickling-unsickling process, culminating in formation of the ISC, and suggest a role for the ISC membrane abnormality in the pathologic rheology of sickle cell disease.     

Retinal pigment epithelium in culture demonstrates a distinct β-adrenergic receptor

Retinal pigment epithelial (RPE) cells in culture, as well as freshly dissected embryonic RPE, exhibit a β-adrenergic receptor. Agonist potency is: l-isoproterenol > (?)epinephrine ≥ (?)norepinephrine ? dopamine. Propranolol blocks this effect. Hydroxybenzylpindolol (HYP), a β-antagonist, also blocks the increase in cAMP elicited by l-isoproterenol. Binding of [¹²⁵I]-hydroxybenzylpindolol, shows a half saturation concentration of 1·1 × 10^?9, m and 2·7 × 10⁵ HYP binding sites per cell. The presence of such distinct β-adrenergic responsiveness indicates a potentially important role for this receptor in RPE cell physiology.     

S-methylation of captopril. Demonstration of captopril thiol methyltransferase activity in human erythrocytes and enzyme distribution in rat tissues

The presence of a methyltransferase enzyme in human red blood cells (RBCs) capable of S-methylation of captopril is described. The apparent Michaelis-Menten (Km) constant for captopril was 0.5 mM and the maximum velocity (Vmax) was 0.391 pmoles S-methylcaptopril (mg protein)-1 min-1. There is some evidence presented to show that S-methylcaptopril inhibited its own formation with a ki value of 5.81 mM. Captopril thiol methyltransferase activity was also examined in rat tissues and was found to be present in all tissue studied. Subcellular localisation studies in rat liver suggest that the enzyme was microsomal in origin. The order of activity was liver greater than heart greater than spleen greater than lung greater than kidney much greater than RBC (rat). This tissue distribution was quite different from previous studies using other thiol substrates and is consistent with more than one form of thiol methyltransferase enzyme in tissues.     

The Three Intracellular Binding Proteins For Retinoids And Their Endogenous Ligands: The Function Of Intracellular Retinal Binding Protein

All-transretinol, all-trans-retinoic acid, 11-cis-retinal, 11-cis-retinol were found to bind to specific intracellular carrier proteins some of which have discrete physiological functions.     

胎儿血样的采集、纯化及其在产前诊断中的应用

80例妊娠15～28周中期妊娠引产和遗传咨询的孕妇,经胎盘抽吸胎血取样所获得的血样中,胎儿红细胞比例为0～99％。胎儿红细胞3％以上,能经成人红细胞选择性溶血法分离得到纯或较纯的胎儿红细胞标本的血样67例。胎血取样成功率为83.75％。纯化的胎儿红细胞G6PD活性测定和微量血红蛋白电泳检查表明:纯化的胎儿红细胞可用于血红蛋白病和红细胞酶缺陷等遗传性疾病的产前诊断。     

Acid phosphatase activity in human neuronal and glial lipofuscin

Summary The ultrastructural demonstration of acid phosphatase activity in neuronal and glial lipofuscin of the aged human brain indicates lysosomal activity. Contrary to the constantly high enzyme activity of astroglial lipofuscin and low activity of oligodendroglial lipofuscin, the enzyme activity of neuronal pigment differs in different locations, i.e., in different neuronal populations. The activity is probably based on the importation of lysosomal enzymes into the pigment component of lipofuscin. These facts indicate the possibility of a continuous autophagosomal function of lipofuscin in neuronal and glial cell physiology. Therefore, the findings are arguments against the view that lipofuscin is a wear-and-tear material only and claim for it an active role in cell metabolism.Supported by the Deutsche Forschungsgemeinschaft (grant Schl. 141/6)