RESUMO
This study is the first to apply a comparative analysis of environmental chemistry, microbiological parameters and bacterioplankton 16S rRNA clone libraries from different areas of a 50 km transect along a trophic gradient in the tropical Guanabara Bay ecosystem. Higher bacterial diversity was found in the coastal area, whereas lower richness was observed in the more polluted inner bay water. The significance of differences between clone libraries was examined with LIBSHUFF statistics. Paired reciprocal comparisons indicated that each of the libraries differs significantly from the others, and this is in agreement with direct interpretation of the phylogenetic tree. Furthermore, correspondence analyses showed that some taxa are related to specific abiotic, trophic and microbiological parameters in Guanabara Bay estuarine system.
Assuntos
Bactérias/crescimento & desenvolvimento , Biodiversidade , Ecossistema , Plâncton/crescimento & desenvolvimento , Água do Mar/microbiologia , Bactérias/genética , Sequência de Bases , Brasil , Água Doce/microbiologia , Variação Genética/genética , Geografia , Dados de Sequência Molecular , Filogenia , Plâncton/genética , RNA Ribossômico 16S/genética , Rios/microbiologia , Salinidade , Clima Tropical , Microbiologia da ÁguaRESUMO
Guanabara Bay is an eutrophic estuarine system located in a humid tropical region surrounded by the second largest metropolitan area of Brazil. This study explores the contrasting environmental chemistry and microbiological parameters that influence the archaeaplankton diversity in a pollution gradient in Guanabara Bay ecosystem. The environments sampled ranged from completely anoxic waters in a polluted inner channel to the adjacent, relatively pristine, coastal Atlantic Ocean. Partial archaeal 16S rDNA sequences in water samples were retrieved by polymerase chain reaction (PCR) and analyzed using denaturing gradient gel electrophoresis (DGGE), cloning, and sequencing. Sequences were subjected to phylogenetic and diversity analyses. Community structure of the free-living archaeal assemblages was different from that of the particle-attached archaea according to DGGE. Gene libraries revealed that phylotype identification was consistent with environmental setting. Archaeal phylotypes found in polluted anoxic waters and in more pristine waters were closely related to organisms that have previously been found in these environments. However, inner bay archaea were related to organisms found in oil, industrial wastes, and sewage, implying that water pollution controls archaea communities in this system. The detection of a substantial number of uncultured phylotypes suggests that Guanabara Bay harbors a pool of novel archaeaplankton taxa.
Assuntos
Archaea/genética , Ecossistema , Água do Mar/microbiologia , Archaea/classificação , Archaea/crescimento & desenvolvimento , Brasil , DNA Arqueal/química , DNA Arqueal/genética , Geografia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Calomys callosus Rengger, 1830 (Rodentia: Cricetidae) is a mouse-like South American wild rodent, which is permissive to Schistosoma mansoni infection. In this paper we studied the effect of schistosomal infection in C. callosus mesenteric and omental milky spots (MS), subsidiary foci of coelom-associated lymphomyeloid tissue (CALT), during the acute, transitional (acute to chronic), and chronic phases of the infection. MS were morphologically analyzed by historical methods, using brightfield and confocal laser scanning microscopies. The MS of infected animals were mainly of lymphomyelocytic (42 to 90 days) and lymphoplasmacytic (160 days of infection) types and showed frequent presence of lymphoid follicles with germinal centers, plasmacytogenesis and plasmacytosis, mastocytosis, megakaryopoiesis, erythropoiesis and less pronounced eosinopoiesis. These results indicate that MS are a preferencial site of germinal-center-dependent and independent plasmacytogenesis, and a bone narrow-like organ, committed with various cellular lineages. The consequence of a C. callosus MS reactivity for schistosomal infection is still unknown and is under investigation.
Assuntos
Animais , Ratos , Arvicolinae/parasitologia , Tecido Linfoide/parasitologia , Omento/parasitologia , Roedores/parasitologia , Esquistossomose mansoni/veterinária , Sinais e Sintomas , Microscopia ConfocalRESUMO
Apresentamos um caso de um jovem de 16 anos de idade, com queixa de dor epigástrica e vômitos após as alimentaçöes. A gastroscopia evidenciou onde estava situad a lesäo ulcerada com 3,0cm de diâmetro. O diagnóstico histopatológico foi de carcinoma gástrico tipo difuso, com moderada quantidade de células em anel de sinete, PAS positivas. O paciente foi operado quatro semanas após o diagnóstico, com quadro de semi-obstruçäo. A peça apresentava invasäo tumoral no limite superior da resecçäo cirúrgica e em profundidade correspondendo a lesäo ulcerada, comprometendo a serosa. O paciente evoluiu satisfatoriamente bem após a cirurgia permanecendo com restriçäo dietética, voltando a apresentar quadro de semi-obstruçäo, vindo falecer quatro meses depois. A incidência no Ceará da neoplasia gástrica é apresentada. O objetivo principal é chamar atençäo para a possibilidade de diagnóstico desse tipo de neoplasia, em pacientes dessa faixa etária, principalmente em regiöes de média a alta incidência de neoplasia gástrica