抗癌及癌化学预防药物的研究:3-乙酰香豆素衍生物的合成及其抗致突活性与结构间的关系

合成了25个3-乙酰香豆素衍生物,其中22个未见报道。体外抗致突活性筛选表明其中部分化合物有不同程度的抗致突活性,并对5,7,8位取代的结构与活性间的关系进行了初步的分析。     

Adriamycin and daunomycin generate reactive oxygen compounds in erythrocytes

Adriamycin and daunomycin produce dose-related cardiac toxicity that may be related to oxygen radicals. Addition of these compounds to human erythrocyte suspensions resulted in stimulation of hexose monophosphate shunt activity that was markedly impaired in the absence of oxyhemoglobin. Evidence for generation of hydrogen peroxide by these compounds was provided by oxidation of reduced glutathione, by 14C- formate oxidation, and by the catalase-aminotriazole trapping technique. These experiments indicate that Adriamycin and daunomycin interact with oxyhemoglobin to generate reactive oxygen metabolites. A similar interaction with oxymyoglobin may occur in the heart and produce oxygen radicals that injure cardiac myocytes.     

Adrenergic receptors in the hypothalamus concerned with control of arterial blood pressure: elicited by electrical and chemical stimulation

The study was made with the help of a chemitrode placed in various areas of the hypothalamus by the stereotaxic technique, for electrical and chemical stimulation (noradrenaline or isoprenaline) before and after microinjection of respective blockers (phenoxybenzamine or practalol). The results indicated the presence of both alpha and beta-adrenoreceptors in the anterior and dorsomedial hypothalamus producing a depressor response, and, the presence of alpha adrenoreceptors in the posterior and lateral hypothalamus producing a pressor response.     

Microrheologic investigation of erythrocyte deformability in diabetes mellitus

This study was undertaken to determine whether diabetes alters the viscoelastic properties of erythrocytes. The oldest and youngest 10% fractions of circulating red cells were separated by centrifugation of freshly drawn blood obtained from ten diabetics with disease of one to 20 years' duration and from an equal number of age- and sex-matched control subjects. Cells from each fraction were suspended in phosphate- buffered saline, and their rheologic behavior was examined in a rheoscope. The elongation of cells, the percentage of cells that tank- treaded in response to shear stress, tank-treading frequency, and the rate of recovery of cell shape upon cessation of shear stress were determined in the oldest and youngest 10% of cells for diabetics as well as for controls. All four parameters were virtually identical for diabetics and controls. Additional aliquots of cells were taken for assessment of nonenzymatic glucosylation of hemoglobin and cell membrane protein. The absence of any measurable difference in rheologic behavior of cells from diabetic and control subjects, despite substantial differences in nonenzymatic glucosylation of hemoglobin and cell membrane proteins, suggests that the magnitude of glucosylation observed in these cellular constituents does not alter the viscoelastic properties of the cells. The implication of these observations is that microvascular complications of diabetes are not attributable to altered deformability of red cells.     

IMMUNOCHROMATOGRAPHIC TEST: A NEW DIMENSION IN DIAGNOSIS OF PLASMODIUM FALCIPARUM MALARIA

75 patients with clinical features suggestive of malaria were studied to evaluate the efficacy of immunochromatographic test (ICT), which detects histidine rich protein-2 antigen secreted by Plasmodium falciparum (Pfhrp-2), as against direct microscopy. There were 40 cases of P falciparum malaria, 14 cases of P vivax malaria and 21 cases of non-malarial fevers. Direct microscopy could detect 27(67.5%) P falciparum cases but failed to detect 13 cases (32.5%) whereas ICT could detect 35(87.5%) P falciparum cases out of 40 but failed to detect 5(12.5%) cases. All the P vivax cases and non-malarial fever cases were negative for ICT. The sensitivity and specificity of ICT is 87.5% and 100% respectively where as the positive predictive value and the negative predictive value of the test is 100% and 87.5% respectively. It is concluded that ICT test is a good adjunct to blood smear studies in fever cases with neurological and multiorgan dysfunction and in antenatal ladies.Key Words: ICT, P falciparum