Search

Prodigiosin is a secondary metabolite produced by Serratia marcercens. As this pigment is suggested to be a cancer drug, genotoxicity studies are necessary. The aim of the present investigation was to evaluate the genotoxic effects of prodigiosin on tumoral and normal cell lines, NCIH-292, MCF-7 and HL-60. A normal line BGMK was used as control. Genomic damage induced by prodigiosin was observed in all tumor lines as well as the control line. The pigment induced the formation of micronuclei in tumor cells. The present data confirm the antitumor potential of prodigiosin. However, these findings also raise concerns regarding its target-specific action, as genotoxic effects on normal cells also occurred.

The mutagenic activities of 16 anti-parasite drugs were screened by the Simultest in both qualitative (spot test) and quantitative (plate incorporation) assays with a Salmonella typhimurium pool composed by the indicator strains TA97, TA 98, TA100 and TA102. Four anti Chagas' disease drugs (nifurtimox, benznidazole, CL 64,855, and MK 436) and two anti-amebae drugs (metronidazole and tinidazole) gave positive results in qualitative tests and incorporation of rat liver microsomes did not alter the results. Comparative dose response curves of the mutagenic activities of CL 64,855, metronidazole and benznidazole obtained by the simultest and by individual Salmonella indicator strains demonstrated that both approachs have similar sensitivities. The results corroborate the validity of the Simultest, as a simplified, fast and economic version of the Ames test in preliminary screening of potential mutagenic drugs. As atividades mutagênicas de 16 drogas com ação anti-parasitária foram avaliadas pelo Simultest em ensaios qualitativos (spot testes) e quantitativos (incorporação em placa) com uma mistura das linhagens indicadoras de Salmonella typhimurium TA97, TA98, TA100 e TA102. Quatro drogas anti-doença de Chagas (nifurtimox, benzonidazol, CL 64,855 e MK 436) e duas drogas anti-amebiase (metronidazol e tinidazol) deram resultados positivos em testes qualitativos e a incorporação de fração microssomal de fígado de rato não alterou os resultados. Curvas comparadas de efeito da dose da atividade mutagênica do metronidazol, benzonidazol e CL 64,855 detectadas pelo Simultest e linhagens indicadoras individuais demonstraram que as duas abordagens possuem sensibilidades semelhantes. Os resultados corroboram a validade do Simultest como uma versão simplificada, rápida e econômica do teste de Ames no rastreamento preliminar de drogas potencialmente mutagênicas.

Soros de carnívoros domésticos (cães e gatos), roedores, e pacientes suspeitos de peste, obtidos durante dois surtos de peste humana e de roedores, um em 1982, no foco da Serra de Baturité/CE e o outro, em 1986, no Planalto da Borborema/PB e soros de carnívoros e de roedores do foco da Chapada do Araripe/PE, obtidos, em 1986, na ausência de casos humanos, foram analisados pelas micro técnicas de hemaglutinação passiva para anticorpos específicos, contra a fração antigênica purificada - F1A - de Yersinia pestis e inibição da hemaglutinação. Os altos percentuais de carnívoros, sorologicamente, positivos encontrados durante os surtos de peste humana, confirmam que esses animais estão implicados no ciclo epidemiológico da peste, nos focos do Nordeste do Brasil, e representam valiosos indicadores das atividades da infecção.Blood sera were obtained from domestic carnivores (dogs and cats), rodents, and plague suspected humans during two Brazilian plague outbreaks that have occurred in Baturité Mountain focus, (Ceará state), in 1982 and Borborema Plateau focus, (Paraíba state), in 1986. Blood sera were also obtained from animals on Araripe Plateau focus, (Pernambuco state), during 1986, when human cases of plague had not been reported. The samples were analysed by passive haemagglutination test for antibodies against the fraction - F1A - of Yersinia pestis concomitant with the passive haemagglutination inhibition test. The high percentage of seropositive carnivores found during the plague outbreaks indicates that these animals may also be involved in the epidemiological cycle of plague in Brazil, and could represent a valuable indicator of the infection activity.

The effects of a single dose (100 mg/kg-body weight of mouse) of oxamniquine on the worm's tegument and paranchyma in relation to the process of immunological granulomatous reaction of the host's liver are described under light and electron microscopy (EM). The lesions caused by the drug are sequentially and simultaneously described in form of swelling, surface bulble and disruption with erosions. Ulceration in the tubercules with loss of spines is often more extensive and severe in male worms and concentration of host's mononuclear cells is observed. The possible role of host's immune response is discussed.

Foram realizados estudos bacteriológicos e/ou sorológicos para diagnóstico da infecção pestosa, em material obtido de 452 pacientes (48 positivos), 1.938 roedores e outros pequenos mamíferos (75 positivos), 4.756 cães (141 positivos) e 3.047 gatos (57 positivos), oriundos de 41 municípios localizados em toda a extensão da área paraibana do Planalto da Borborema. A infecção foi encontrada em 21 municípios. Foram isoladas 20 cepas de Yersinia pestis de amostras coletadas de três pacientes e 17 roedores. Estas cepas apresentam características bioquímicas, fatores de virulência, sensibilidade aos antibióticos e poder patogênico experimental semelhantes ao de cepas isoladas anteriormente. Pelos estudos realizados não foram observados, no surto de peste que eclodiu em setembro de 1986 na Paraíba, fatores diferentes dos observados nos outros focos do nordeste do Brasil. During a plague outbreak in the Borborema Plateu focus (Paraíba), bacteriological and serological studies were carryed out in material from 452 patients (48 positives), 1,938 rodents and other small mammals (75 positives), 4,756 dogs (141 positives) and 2,047 cats (57 positives) obtained from 41 counties (out of which, 21 produced positive samples). Twenty Yersinia pestis strains isolated from material from 3 patients ans 17 rodents, displayed biochemical reactions, virulence factors, antibiotic susceptibility and animal experimental pathogenicity similar to those observed in strains previously isolated. According to our findings this recent plague outbreak did not exhibite different factors from those observed during prior outbreaks in other plague foci in the northeast of Brazil.