Production and characterization of protease from Penicillium aurantiogriseum URM 4622

Proteases with new properties are required due to their increasing industrial importance. In this work, the optimal fermentation conditions for the production of a protease from Penicillium aurantiogriseum dierchx (URM-4622) are presented together with partial characterization of the protease catalytic properties. The batch fermentation conditions that allow for the highest specific proteolytic activity are 26 ºC, pH 7.0, and 25 % saturation dissolved O2 concentration. The obtained protease is stable over a wide range of pH (5.8 to 9.5) and temperature (25 to 40 ºC) values. In the presence of Zn2+ a 26 % reduction in the enzyme proteolytic activity occurs and, in contrast, Mn2+ enhances its activity by 28.9 %. 96.2 % and 70.8 % of the protease activity are maintained after 90 min incubation in 5 and 10 % (v/v) H2O2 aqueous solutions, respectively. PMSF inhibition reveals that this enzyme is a serine protease. Protease is able to hydrolyze different proteins

Screening Of Miners And Millers At Decreasing Levels Of Asbestos Exposure: Comparison Of Chest Radiography And Thin-section Computed Tomography.

Chest radiography (CXR) is inferior to Thin-section computed tomography in the detection of asbestos related interstitial and pleural abnormalities. It remains unclear, however, whether these limitations are large enough to impair CXR´s ability in detecting the expected reduction in the frequency of these asbestos-related abnormalities (ARA) as exposure decreases. Clinical evaluation, CXR, Thin-section CT and spirometry were obtained in 1418 miners and millers who were exposed to progressively lower airborne concentrations of asbestos. They were separated into four groups according to the type, period and measurements of exposure and/or procedures for controlling exposure: Group I (1940-1966/tremolite and chrysotile, without measurements of exposure and procedures for controlling exposure); Group II (1967-1976/chrysotile only, without measurements of exposure and procedures for controlling exposure); Group III (1977-1980/chrysotile only, initiated measurements of exposure and procedures for controlling exposure) and Group IV (after 1981/chrysotile only, implemented measurements of exposure and a comprehensive procedures for controlling exposure). In all groups, CXR suggested more frequently interstitial abnormalities and less frequently pleural plaques than observed on Thin-section CT (p<0.050). The odds for asbestosis in groups of decreasing exposure diminished to greater extent at Thin-section CT than on CXR. Lung function was reduced in subjects who had pleural plaques evident only on Thin-section CT (p<0.050). In a longitudinal evaluation of 301 subjects without interstitial and pleural abnormalities on CXR and Thin-section CT in a previous evaluation, only Thin-section CT indicated that these ARA reduced as exposure decreased. CXR compared to Thin-section CT was associated with false-positives for interstitial abnormalities and false-negatives for pleural plaques, regardless of the intensity of asbestos exposure. Also, CXR led to a substantial misinformation of the effects of the progressively lower asbestos concentrations in the occurrence of asbestos-related diseases in miners and millers.10e011858

Production and characterization of protease from Penicillium aurantiogriseum URM 4622

Abstract Proteases with new properties are required due to their increasing industrial importance. In this work, the optimal fermentation conditions for the production of a protease from Penicillium aurantiogriseum dierchx (URM-4622) are presented together with partial characterization of the protease catalytic properties. The batch fermentation conditions that allow for the highest specific proteolytic activity are 26 ºC, pH 7.0, and 25 % saturation dissolved O 2 concentration. The obtained protease is stable over a wide range of pH (5.8 to 9.5) and temperature (25 to 40 ºC) values. In the presence of Zn 2+ a 26 % reduction in the enzyme proteolytic activity occurs and, in contrast, Mn 2+ enhances its activity by 28.9 %. 96.2 % and 70.8 % of the protease activity are maintained after 90 min incubation in 5 and 10 % (v/v) H 2 O 2 aqueous solutions, respectively. PMSF inhibition reveals that this enzyme is a serine protease. Protease is able to hydrolyze different proteins

Potencial genético da aveia, como produtora de grãos no sul do Brasil

Yield and other agronomic traits were studied in six experiments with oats (Avena sativa L.) established in the Southern Brazil, during the years 1982 to 1984. The grain yield and hectoliter wight in different genotypes showed high progress; however, plant stature and heading time did not change in the last three years. The results suggest that plant breeding programmes should release new genotypes to increase stability and yield potential. O rendimento de grãos e outros caracteres de importância agronômica foram estudados em seis experimentos de aveia estabelecidos na região sul do Brasil, entre os anos de 1982 a 1984. O rendimento de grãos e o peso do hectolitro nos diferentes genótipos demonstraram um alto progresso; entretanto, a estatura e o ciclo de desenvolvimento de planta não apresentaram alterações nos últimos três anos. Os resultados sugerem que os programas de melhoramento devem continuar criando e testando novos genótipos anualmente, com o objetivo de incrementar a estabilidade e o potencial de rendimento de grãos.

Intraspecific variation in sensitivity to habitat fragmentation is influenced by forest cover and distance to the range edge

The relative effects of habitat loss and fragmentation on biodiversity have been a topic of discussion for decades. While it is acknowledged that habitat amount can mediate the effects of habitat fragmentation, it is unclear what other factors may drive inter- and intraspecific variation in fragmentation effects and their implications for conservation. We tested whether the effects of forest fragmentation on 362 bird species' occurrence in the Atlantic Forest of Brazil are mediated by distance to geographic range edge and habitat amount, and whether these effects explain intraspecific variation across populations. Using a single binomial linear mixed effects model, we found that fragmentation had mostly negative effects on occurrence probability up to 1080 km from the species' range edge, independent of habitat amount. We also show that above this distance, fragmentation has predominantly positive effects, more accentuated in deforested landscapes. We demonstrate that fragmentation effects can be both positive and negative, indicating that different populations of the same species can respond differently depending on distance to range edge and local forest cover. Our results help clarify one of the drivers of contradictory results found in the fragmentation literature and highlight the importance of preventing habitat fragmentation for the conservation of endangered populations. Conservation initiatives should focus on minimising fragmentation closer to range edges of target species and in regions where species range edges overlap

Presença de Aedes aegypti em Bromeliaceae e depósitos com plantas no Município do Rio de Janeiro, RJ

Relata-se a freqüência de vegetais Bromeliaceae e de outros criadouros com plantas positivos para Aedes aegypti durante dois ciclos operacionais (tratamento focal) consecutivos no Município do Rio de Janeiro, RJ, cujos períodos foram de 12 de novembro de 2000 a 9 de março de 2001 e 12 de março de 2001 a 15 de junho de 2001. O trabalho destaca as implicações epidemiológicas oriundas da crescente utilização dessas plantas para fins decorativos.The frequency of Bromeliaceae and other plant breeding places where Aedes aegypti can be found is reported during two consecutive operational cycles (focal treatment) in the city of Rio de Janeiro. These cycles took place from November 12 2000 to March 9 2001 and from March 12 2001 to June 15 2001. This study concentrates on the epidemiological implications resulting from the growing use of these plants as decorative living objects