Indoor air microbiological evaluation of offices, hospitals, industries, and shopping centers

In this study it was compared the MAS-100 and the Andersen air samplers´ performances and a similar trend in both instruments was observed. It was also evaluated the microbial contamination levels in 3060 samples of offices, hospitals, industries, and shopping centers, in the period of 1998 to 2002, in Rio de Janeiro city. Considering each environment, 94.3 to 99.4% of the samples were the allowed limit in Brazil (750 CFU/m3). The industries´ results showed more important similarity among fungi and total heterotrophs distributions, with the majority of the results between zero and 100 CFU/m3. The offices´ results showed dispersion around 300 CFU/m3. The hospitals' results presented the same trend, with an average of 200 CFU/m3. Shopping centers' environments showed an average of 300 CFU/m3 for fungi, but presented a larger dispersion pattern for the total heterotrophs, with the highest average (1000 CFU/m3). It was also investigated the correlation of the sampling period with the number of airborne microorganisms and with the environmental parameters (temperature and air humidity) through the principal components analysis. All indoor air samples distributions were very similar. The temperature and air humidity had no significant influence on the samples dispersion patterns

Evaluation of phenotypic markers associated with pathogenicity in the genus Listeria Avaliação de marcadores fenotípicos associados à patogenicidade no gênero Listeria

A total of 130 Listeria strains were tested in order to evaluate lecithinase production and capacity for Congo red adsorption as markers of pathogenicity. The strains were identified according to acid production from sugars and by the CAMP test and the data were correlated with the ability to produce keratoconjunctivitis in guinea pigs. L. monocytogenes cultures presented 51.8% and 88.8% positivity rates for Congo red adsorption and lecithinase production, respectively, whereas 80.8% and 100% for L. innocua cultures were negative for the two test, respectively<br>Com propósito de avaliar a produção de lecitinase e a capacidade de adsorção do corante vermelho Congo como marcadores de patogenicidade, foram estudadas 130 amostras de Listeria. Estas amostras foram identificadas segundo a produção de ácido a partir de açúcares aliada ao teste CAMP, correlacionando-se estes dados à capacidade de produção de ceratoconjuntivite em cobaio. As culturas de L. monocytogenes apresentaram taxas de positividade para a adsorção do corante e produção de lecitinase de 51,8 e 88,8%, respectivamente, enquanto 80,8% e 100% das culturas de L. innocua foram negativas para os referidos testes