Searching for bioindicators of forest fragmentation: passerine birds in the Atlantic forest of southeastern Brazil / Busca por bioindicadores de fragmentação florestal: aves Passeriformes na Floresta Atlântica do Sudeste do Brasil

Aiming to evaluate the potential of Passerine birds as bioindicators of forest fragmentation, we studied the avifauna in the mountain region of the state of Rio de Janeiro by mist-netting between 2001 and 2005. We sampled six sites, including four small fragments (from 4 to 64 ha) in an agricultural area (Teresópolis), one second-growth forest (440 ha - Miguel Pereira) and a continuous forest (10,600 ha, Serra dos Órgãos National Park - SONP). Indicator Species analysis and a Monte Carlo test were run to detect associations between species and sites, considering at least 30 percent of perfect indication and a significant value for the statistical test, only considering species with at least 10 captures. A total of 30 Passerine birds were sampled, and due to their association to the largest area (SONP), we considered Sclerurus scansor, Mionectes rufiventris, Chiroxiphia caudata and Habia rubica as the best indicators for this area. Five species were more captured not by chance in the 440 ha second-growth: Conopophaga melanops, Myiobius barbatus, Myrmeciza loricata, Philydor atricapillus and Schiffornis virescens and no species were related to any small fragment. This analysis has identified specialized Passerine species in many aspects (foraging substract, needs for nesting, rarity status), and it can be a valuable tool for detecting possible bioindicators.

Para avaliar o potencial de Passeriformes como bioindicadores de fragmentação florestal na Mata Atlântica, estudamos a avifauna da região serrana do Rio de Janeiro, utilizando capturas com redes de neblina entre 2001 e 2005. Foram amostradas seis áreas, sendo quatro pequenos fragmentos (de 4 a 64 ha) em áreas agrícolas (Teresópolis), uma mata secundária com cerca de 40 anos (440 ha - Miguel Pereira) e uma área de mata contínua de 10600 hectares (Parque Nacional da Serra dos Órgãos - PARNASO). A análise de espécies indicadoras e o teste de Monte Carlo foram empregados para que se verificassem as espécies mais associadas a cada local amostrado, considerando-se um mínimo de 30 por cento de indicação e valor significativo para o teste mencionado, utilizando-se somente espécies com 10 ou mais capturas. Foi amostrado um total de 30 espécies e, pela sua associação com a maior área (PARNASO), consideramos Sclerurus scansor, Mionectes rufiventris, Chiroxiphia caudata e Habia rubica como as melhores indicadoras. Cinco espécies foram mais capturadas não ao acaso na área de 440 ha: Conopophaga melanops, Myiobius barbatus, Myrmeciza loricata, Philydor atricapillus e Schiffornis virescens. Nenhuma espécie foi associada aos pequenos fragmentos. Como esta análise identificou espécies de Passeriformes especialistas em diversos aspectos (substrato de forrageio, locais de nidificação, status de raridade), ela pode ser uma ferramenta útil na detecção de possíveis bioindicadores.

Fish diversity along spatial gradients in the Itaipu Reservoir, Paraná, Brazil

Padrões locais e regionais de diversidade de peixes no reservatório de Itaipu foram avaliados e relacionados aos gradientes longitudinal ou rioûrepresa (dividido nas zonas fluvial, intermediária e lacustre) e transversal ou cabeceiraûfoz dos tributários (dividido em trechos lóticos e lênticos dos tributários e margens do reservatório). As coletas foram realizadas trimestralmente durante dois anos. Foram capturadas 85 espécies. Os padrões de diversidade local (a) e turnover (b) apresentaram diferenças significativas ao longo dos gradientes espaciais. Ao longo do gradiente longitudinal, as diversidades total e a foram maiores nas zonas fluvial e intermediária. Ao longo do gradiente transversal, as diversidades total e a aumentaram gradualmente do trecho lótico dos tributários às margens do reservatório. Os trechos lóticos e lênticos dos tributários apresentaram os maiores valores de diversidade b, indicando a heterogeneidade na composição de espécies das sub-bacias. Com base nos resultados deste estudo, recomendamos algumas ações de manejo para o reservatório.

The use of a muscle graft to repair a segmentary nerve defect. An experimental study using the sciatic nerve of rats as model.

The use of a devitalized skeletal muscle graft and conventional nerve graft to repair a 5mm long segmentary sciatic nerve lesion was studied in rats by means of functional, morphometric and spinal cord motor neuron cell response evaluation. Thirty-four rats were used and divided into four groups according to the procedure: (1) sham operation; (2) conventional nerve grafting; (3) muscle grafting; (4) unrepaired lesion. The sciatic functional index (SFI) was evaluated every fortnight up to the 105th postoperative day by measuring three parameters in the rats' footprint. The animals of Groups 2 and 3 presented initial complete functional loss, followed by slow but steady recovery, with final similar SFIs. The histologic and morphometric studies showed an increased small diameter/thin myelin sheath nerve fiber density distally to the lesion site for both types of graft. An increased population of motor neurons was observed in the anterior horn of the lumbar spinal cord segment with both types of grafts, but not in the control groups. The SFI, histologic and morphometric data did not differ significantly between the two types of graft, thus indicating a similar behavior. The authors conclude that a 5mm long skeletal muscle graft works as well as a conventional nerve graft.

Isolation of an aspartic proteinase precursor from the egg of a hard tick, Boophilus microplus.

An aspartic proteinase precursor, herein named BYC (Boophilus Yolk pro-Cathepsin) was isolated from eggs of the hard tick, Boophilus microplus. As judged by electrophoresis on sodium dodecyl sulfate polyacrylamide slab gel (SDS-PAGE), purified BYC presented 2 bands of 54 and 49 kDa, bearing the same NH2-terminal amino acid sequence. By Western blot analysis, BYC was also found in the haemolymph, indicating an extraovarian site of synthesis. Several organs were incubated in culture medium with [35S]methionine, and only the gut and fat body showed synthesis of BYC polypeptides. Protein sequencing of both the NH2-terminal and an internal sequence obtained after cyanogen bromide (CNBr) cleavage of BYC revealed homology with several aspartic proteinase precursors. Incubation at pH 3.5 resulted in autoproteolysis of BYC, which produced the mature form of the enzyme, that displayed pepstatin-sensitive hydrolytic activity against haemoglobin. Western blot analysis using anti-BYC monoclonal antibodies showed proteolytic processing of BYC during embryogenesis and suggested activation of the enzyme during development. A role of BYC in degradation of vitellin, the major yolk protein of tick eggs, is discussed.

Isolation of Pseudomonas cepacia in cystic fibrosis patient.

Pulmonary infection on cystic fibrosis (CF) patients are associated with a limited qualitative number of microorganisms. During the colonization process, Staphylococcus aureus usually precedes Pseudomonas aeruginosa. This latter is at first non-mucoid, being replaced or associated to a mucoid morphotype which is rare in other diseases. In 1980, Pseudomonas cepacia appeared as an important agent in CF pulmonary infections with a mean frequency of about 6.1% isolations in different parts of the world. The primus colonization mainly occurs in the presence of pre-existent tissue lesions and the clinical progress of the disease is variable. In some patients it can be fulminant; in others it can cause a gradual and slow decrease in their pulmonary functions. The concern with this germ isolation is justified by its antibiotic multiple resistance and the possibility of direct transmission from a colonized patient to a non-colonized one. We reported the first case of P. cepacia infection in a CF patient in our area. The microbiological attendance to this patient had been made from 1986 to 1991 and the first positive culture appeared in 1988. The sensitivity profile showed that the primus colonization strain was sensitive to 9 of 17 tested antibiotics, however in the last culture the strain was resistant to all antibiotics. These data corroborate the need for monitoring the bacterial flora on CF patients respiratory system.

Avaliacao de metodos "in vitro" para estudo da atividade da associacao de gentamicina e carbenicilina em Pseudomonas aeruginosa. / An evaluation of \"in vitro\" methods for studying the combined activity of gentamicin and carbenicillin on Pseudomonas aeruginosa

Trinta e duas amostras de Pseudomonas aeruginosa foram expostas a acao combinada de gentamicina e carbenicilina, visando a deteccao de efeito sinergico, atraves do emprego de dois metodos: um teste de difusao em tiras de papel impregnadas com antibiotico e dispostas transversalmente, e o procedimento padrao - "teste do tabuleiro de xadrez" em meio liquido. O teste padrao mostrou acao sinergica para 20 amostras. Com oito, o sinergismo foi visto apenas em relacao a um antibiotico. Para as 12 amostras restantes observou-se efeito indiferente. O teste de difusao detectou sinergismo para 13 amostras e acao indiferente para 10 amostras, o que corresponde a 22% de resultados falso-negativos e 6% de falso-positivos, quando comparado aos resultados obtidos com o procedimento padrao