Universidade Estadual de Londrina

About: Universidade Estadual de Londrina is a education organization based out in Londrina, Brazil. It is known for research contribution in the topics: Population & Toxoplasma gondii. The organization has 13052 authors who have published 19291 publications receiving 212123 citations.

Genotoxicity and mutagenicity of water contaminated with tannery effluents, as evaluated by the micronucleus test and comet assay using the fish Oreochromis niloticus and chromosome aberrations in onion root-tips

Abstract: Cytotoxicity of metals is important because some metals are potential mutagens able to induce tumors in humans and experimental animals. Chromium can damage DNA in several ways, including DNA double strand breaks (DSBs) which generate chromosomal aberrations, micronucleus formation, sister chromatid exchange, formation of DNA adducts and alterations in DNA replication and transcription. In our study, water samples from three sites in the Corrego dos Bagres stream in the Franca municipality of the Brazilian state of Sao Paulo were subjected to the comet assay and micronucleus test using erythrocytes from the fish Oreochromis niloticus. Nuclear abnormalities of the erythrocytes included blebbed, notched and lobed nuclei, probably due to genotoxic chromium compounds. The greatest comet assay damage occurred with water from a chromium-containing tannery effluent discharge site, supporting the hypothesis that chromium residues can be genotoxic. The mutagenicity of the water samples was assessed using the onion root-tip cell assay, the most frequent chromosomal abnormalities observed being: c-metaphases, stick chromosome, chromosome breaks and losses, bridged anaphases, multipolar anaphases, and micronucleated and binucleated cells. Onion root-tip cell mutagenicity was highest for water samples containing the highest levels of chromium.

Rickettsial Infection in Animals and Brazilian Spotted Fever Endemicity

Abstract: We compared the rickettsial infection status of Amblyomma cajennense ticks, humans, dogs, and horses in both Brazilian spotted fever (BSF)–endemic and –nonendemic areas in the state of Sao Paulo, Brazil Most of the horses and few dogs from BSF-endemic areas had serologic titers against Rickettsia rickettsii antigens In contrast, no dogs or horses from BSF-nonendemic areas had serologic titers against R rickettsii antigens, although they were continually exposed to A cajennense ticks All human serum samples and ticks from both areas were negative by serologic assay and polymerase chain reaction, respectively Our results indicate that surveys of horse serum are a useful method of BSF surveillance in areas where humans are exposed to A cajennense ticks In addition, we successfully performed experimental infection of A cajennense ticks with R parkeri