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Plants used in traditional medicine are rich sources of hemolysins and cytolysins, which are potential bactericidal and anticancer drugs. The present study demonstrates for the first time the presence of a hemolysin in the leaves of Passiflora quadrangularis L. This hemolysin is heat stable, resistant to trypsin treatment, has the capacity to froth, and acts very rapidly. The hemolysin activity is dose-dependent, with a slope greater than 1 in a double-logarithmic plot. Polyethylene glycols of high molecular weight were able to reduce the rate of hemolysis, while liposomes containing cholesterol completely inhibited it. In contrast, liposomes containing phosphatidylcholine were ineffective. The Passiflora hemolysin markedly increased the conductance of planar lipid bilayers containing cholesterol but was ineffective in cholesterol-free bilayers. Successive extraction of the crude hemolysin with n-hexane, chloroform, ethyl acetate, and n-butanol resulted in a 10-fold purification, with the hemolytic activity being recovered in the n-butanol fraction. The data suggest that membrane cholesterol is the primary target for this hemolysin and that several hemolysin molecules form a large transmembrane water pore. The properties of the Passiflora hemolysin, such as its frothing ability, positive color reaction with vanillin, selective extraction with n-butanol, HPLC profile, cholesterol-dependent membrane susceptibility, formation of a stable complex with cholesterol, and rapid erythrocyte lysis kinetics indicate that it is probably a saponin.

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Epidemiological studies have implicated maternal protein-calorie deficiency as an important public health problem in developing countries. Over the last decades, a remarkable diffusion of electricity and an increased level of the electromagnetic field (EMF) in the environment have characterized modern societies. Therefore, researchers are concerned with the biological effects of 50-60 Hz, EMF. The aim of this paper is to show the effects of EMF of 60 Hz, 3 µT, exposure for two hours per day in the regulation of the hormonal and metabolic concentrations in pregnant rats, which were fed by Regional Basic Diet (RBD) during their pregnancy as compared with pregnant rats fed a standard diet. Pregnant rats exposed to EMF of 60 Hz, 3 µT, over the pregnancy and fed with RBD presented an increase in glucose release when compared with the Group subjected only to the RBD ration. Rats fed RBD presented a decrease in their insulin and cortisol serum levels when compared with the Group fed with casein. The T 3 and T 4 concentrations presented the greatest variation among the Groups. The relation T 4 :T 3 was much exaggerated in the Group subjected to RDB and exposed to EMF when compared to the others. In conclusion, the group subjected to the association of EMF and undernutrition suffered a decrease in its serum concentration of T 4 and T 3 when compared to the well-nourished group and the relationship T 4 :T 3 in the former group was almost eighteen-fold the later one.Keywords: casein, electromagnetic field, metabolism, hormone, regional basic diet, undernourished pregnant rats. Efeitos do campo eletromagnético, 60 Hz, 3µT, na regulação hormonal e metabólica de ratas prenhes desnutridas ResumoEstudos epidemiológicos têm mostrado que a deficiência proteico-calórica é um importante problema nos países em desenvolvimento. Durante as últimas décadas, a sociedade moderna tem sido caracterizada pelo aumento no número de equipamentos elétricos e como consequência um aumento no nível do campo eletromagnético (CEM) no ambiente. No entanto, os pesquisadores estão preocupados com os efeitos biológicos dos CEM de 50-60 Hz. O objetivo deste artigo é mostrar os efeitos do CEM de 60 Hz, 3 µT, nas concentrações hormonais e metabólicas de ratas prenhes, expostas duas horas por dia ao CEM, alimentadas pela Dieta Básica Regional (DBR) comparando com ratas submetidas às mesmas condições, mas alimentas com dieta padrão. Ratas prenhes expostas ao CEM de 60 Hz, 3 µT, durante a prenhez e alimentadas com a DBR apresentaram um aumento na liberação de glicose quando comparadas com o grupo alimentado pela DBR sem CEM. As ratas alimentadas pela DBR apresentaram uma diminuição nos níveis de insulina e cortisol quando comparadas com o grupo alimentado pela caseína. As concentrações de T 3 e T 4 apresentaram a maior variação entre os grupos. A relação T 4 :T 3 foi muito exagerada no grupo alimentado pela DBR e exposto ao CEM quando comparado com os outros. Conclusão, os animais que foram submetidos à desnutrição e ao CEM sofreram uma diminuição na ...

The aim of the present study was to observe how the exposition of the pregnant rats to the electromagnetic field (EMF), with frequency of 60 Hz, magnetic field of 3 microT for 2 h per day and/or using the so-called regional basic diet (RBD) influenced the reflex maturation in their offspring. Four groups were formed: Group A (casein), B (casein and EMF), C (RBD) and D (RBD and EMF). The diet manipulation occurred during the pregnancy. The reflexes--assessed daily between 12:00 and 14:00--were: palm grasp (PG), righting reflex (RR), cliff avoidance (CA), vibrissae placing (VP), negative geotaxis (NG), auditory startle (AS) and free-fall righting (FFR). The association between EMF and deficient diet caused a delay in all reflexes when compared with Group A. When the diets were compared with both groups exposed to EMF, the delay occurred in the RR, VP, NG and CA in Group D. In the Groups C and A, the delay was observed in RR, CA, VP, NG, AS and PG. In relation to the EMF, Group B differed from Group A in CA, AS, FFR and PG and Group D differed from C in the PG. In conclusion, all the reflexes studied in this research were delayed by the association of the EMF with undernutrition during pregnancy.

RESUMO:O Ricinus communis L. pertence à família das Euforbiáceas, possui frutos típicos de onde é extraído o óleo de rícino, altamente tóxico. Neste estudo foi analisado o efeito do extrato de Ricinus communis L na marcação de hemácias com Tc-99m através do controle radioquímico. Os resultados mostraram que no controle radioquímico por meio da cromatografia, foi observado que o extrato marcado com Tc-99m mostrou duas frações com 130.007 e 494.592 cpm, e na marcação de hemácias, com %ATI de 61.88 e 41.32% nas frações 1 e 2. Foi concluído que o extrato de R. communis L. altera a captação do Tc-99m in vitro, competindo com o material radioativo em possíveis sítios de ligação nas células vermelhas do sangue, como a capacidade de oxidação do íon estanoso ou por competição com o íon pertecnetato. Unitermos:Ricinus communis, Tecnécio-99m, controle radioquímico, marcação de hemácias.ABSTRACT: "Assessment of the radiochemical control of Ricinus communis L. and Tc99m with the labeling of red blood cells". Ricinus communis L. belongs to the Euphorbiaceae family, from whose fruits the ricin oil is extracted, highly toxic. In this study it was analyzed the effect of the extract of Ricinus communis L. in the labeling of red blood cells with Tc-99m through the radiochemical control. The results showed that in the radiochemical control through chromatography, it was observed that the extract labeled with Tc-99m showed two fractions with 130.007 and 494.592 cpm, and in the labeling of red blood cells, with %ATI of 61.88 and 41.32% in the fractions 1 and 2. It has been concluded that the extract of Ricinus communis alters the captivating of Tc-99m in vitro, competing with the radioactive material in the possible binding sites of the red blood cells, as well in the capacity of oxidation of the stannous ion or by competition with the pertechnetate ion.

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