Universidade Federal Rural do Rio de Janeiro

About: Universidade Federal Rural do Rio de Janeiro is a education organization based out in Seropédica, Brazil. It is known for research contribution in the topics: Population & Species richness. The organization has 6405 authors who have published 9852 publications receiving 105911 citations.

Rhodolith beds in Brazil: a new potential habitat for marine bioprospection

Abstract: Rhodoliths are the free-living forms of a number of nongeniculate coralline algae. Rhodolith beds are a common feature of subtidal environments and have been recognized as important carbonate producers and paleoenvironmental indicators, as well as recognized as habitat-forming species. The rhodolith structure provides a hard three-dimensional substrate serving as microhabitat for a wide range of biodiversity, including commercially importance species. The largest known latitudinal occurrence range of rhodolith beds ais on the Brazilian coastal shelf from 2°N to 25°S. Despite their importance for the Brazilian benthic communities, only in the last decade sampling efforts allowed a more comprehensive understanding of the beds' distribution, their structure and associated communities, as well as data concerning the influence of environmental factors on rhodolith bed structure and dynamics. In this work, we review the available information on the biodiversity associated with the recently described Brazilian rhodolith beds of the continental shelf and oceanic islands, focusing on the associated organisms with potential for bioprospection research.

Community ecology of the metazoan parasites of Banded Croaker, Paralonchurus brasiliensis (Osteichthyes: Sciaenidae), from the coastal zone of the State of Rio de Janeiro, Brazil

Abstract: Ninety-three specimens of banded croaker, Paralonchurus brasiliensis (Steindachner, 1875), collected from Pedra de Guaratiba (23°01'S, 43°38'W), coastal zone, State of Rio de Janeiro, Brazil, between September 2001 and March 2002, were necropsied to study their infracommunities of metazoan parasites. Fifteen species of metazoan parasites were collected. Paralonchurus brasiliensis is a new host record for 13 parasite species. The majority of fishes were parasitized by one or more metazoan. Larvae of Contracaecum sp. proved to be the dominant species, with highest prevalence and abundance values. The parasite species of P. brasiliensis showed the typical aggregated distribution pattern. Prevalence and abundance of Procamallanus (Spirocamallanus) pereirai was positively correlated with the host total length. Abundance of Contracaecum sp. was positively correlated with the host total length. The abundances of a pair of adult endoparasites (Aponurus laguncula - Procamallanus (S.) pereirai) showed negative covariation and one pair of larvae stages of endoparasites (Nybelinia sp. - Contracaecum sp.) showed positive covariations between their abundances. Paralonchurus brasiliensis showed a metazoan parasite community composed by generalist species, little ordered and with scarce quantitative evidences of interspecific associations. These patterns agree with those detected in preceding studies about the parasite communities of Neotropical sciaenid fishes.

Prevalence of canine infection from endemic areas of American cutaneous leishmaniasis in Paracambi District, Rio de Janeiro State, between 1992 and 1993

Abstract: In the district of Paracambi, State of Rio de Janeiro an epidemiological survey for American tegumentary leishmaniasis in canine population was carried out in endemic localities. A total of 179 dogs was registered and 138 (77.1%) examined for their clinical aspects, development of delayed hypersensitivity (DHS) with Imunoleish® antigen and serological responses by indirect immunofluorescent reaction and enzyme-linked immunosorbent assay. In 9 (6.5%) dogs with active cutaneous lesions or suspect scars, 66.7% were caused by Leishmania sp; 44.4% produced infection in hamsters and showed growth in culture media, which was considered to be compatible with the species of Leishmania braziliensis complex. The molecular characterization (isoenzyme and KDNA restriction profiles) defined two strains with similar profiles for L. (Viannia) braziliensis. The prevalence of canine infection estimated by the cutaneous test, IFR and ELISA was 10.1%, 16.7% and 27.8%, respectively. The presence of clinical / sub-clinical form of ATL in canine population associated with human infections suggested that the dog can act as source of infection as well as for dissemination of the disease.

Dinâmica da serapilheira e transferência de nitrogênio ao solo, em plantios de Pseudosamanea guachapele e Eucalyptus grandis

Abstract: Este trabalho teve como objetivo avaliar a deposicao de serapilheira e a transferencia de N associada as folhas e foliolos desse residuo em plantios puros e consorciado de guachapele (Pseudosamanea guachapele) e eucalipto (Eucalyptus grandis), aos sete anos de idade, em Seropedica, RJ. No ano de avaliacao (2000/2001) a deposicao anual de serapilheira nos diferentes plantios nao diferiu significativamente 12,75 Mg ha-1 (guachapele); 11,84 Mg ha-1 (eucalipto) e 12,44 Mg ha-1 (consorciado). Mesmo com pequena participacao na composicao da serapilheira em plantio consorciado (11% do total depositado), a leguminosa proporciona reducao no tempo medio de residencia dos residuos no solo de 0,3 ano, comparativamente ao plantio puro de eucalipto.

Neutrophils increase or reduce parasite burden in Trypanosoma cruzi-infected macrophages, depending on host strain: role of neutrophil elastase.

Abstract: Neutrophils are involved in the initial steps of most responses to pathogens and are essential components of the innate immune response. Due to the ability to produce and release various soluble mediators, neutrophils may participate in the regulation of the inflammatory response. Little is known about the role of neutrophils during protozoan infections including infection by Trypanosoma cruzi. In the present study we investigated the importance of inflammatory neutrophils on macrophage activation and T. cruzi replication in vitro, in cells obtained from BALB/c mice and C57Bl/6 mice. Co-cultures of BALB/c apoptotic or live neutrophils with infected peritoneal macrophages resulted in increased replication of the parasites and in the production of TGF-β and PGE2. The treatment with anti-TGF-β neutralizing antibody and COX inhibitor blocked the parasite replication in vitro. On the other hand, co-cultures of T. cruzi infected macrophages with live neutrophils isolated from C57BL/6 mice resulted in decreased number of trypomastigotes in culture and increased production of TNF-α and NO. The addition of anti-TNF-α neutralizing antibody or elastase inhibitor resulted in the abolishment of macrophage microbicidal effect and increased parasite replication. Addition of elastase to infected macrophages reduced the replication of the parasites, and on the other hand, addition of a selective inhibitor of iNOS increased parasite growth, suggesting the role of NO in this system. Our findings reveal that neutrophils may regulate T. cruzi experimental infection and determine susceptibility and resistance to infection.