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Staphylococcus aureus produces exoproteins that contribute to its ability to colonize the mammary gland such as hemolysins, coagulase, slime, and protein A. This study characterized phenotypically and genotypically these virulence factors in 50 Staph. aureus isolates. These isolates were obtained from milk samples from subclinical mastitis cases identified in 15 dairy cattle farms located in the state of Rio de Janeiro, Brazil. All of the confirmed Staph. aureus samples were PCR positive for the coa gene, which displayed 3 different size polymorphisms. The amplification of the spaA X region yielded a single amplicon for each isolate with the prevalent amplicon sized 315 bp. The Staph. aureus isolates were 24 and 16% positive for the hla and hlb genes, respectively, and 22 and 20% positive for the icaA and icaD genes, respectively. Amplification of the agr gene RNAIII was positive in 74% of the strains. Twenty-seven different profiles were identified among the samples, indicating a great diversity of Staph. aureus involved in the etiology of mastitis cases in the analyzed region. These findings are valuable to the comprehension of the distribution of the profiles of Staph. aureus strains isolated from subclinical mastitis cases in the state of Rio de Janeiro. [ABSTRACT FROM AUTHOR]

Microbial populations are primarily responsible for the decomposition of organic residues, the nutrients cycle, and the flow of energy inside of soil. The present study was undertaken to link soil microbiological and soil biochemical parameters with soil- and litter-quality conditions in the surface layer from 5 sites differing in plant cover, in stand age, and in land-use history. The aim was to see how strongly these differences affect the soil microbial attributes and to identify how microbiological processes and structures can be influenced by soil and litter quality. Soil and litter samples were collected from 5 sites according to different land use: preserved forest, nonpreserved forest, secondary forest, pasture, and eucalyptus plantation. Soil and litter microbial biomass and activity were analysed and DNA was extracted from soil. The DNA concentrations and soil microbial C and N correlated positively and significantly, suggesting that these are decisive nutrients for microbial growth and time required for microbial biomass renewal. The litter microbial biomass represented a source of C and N higher than soil microbial biomass and can be an important layer to contribute to tropical soil with low C and N availability. The litter quality influenced the litter and soil microbial biomass and activity and the soil bacterial diversity. The chemical and nutritional quality of the litter influenced the structure and microbial community composition in the eucalyptus plantation. [ABSTRACT FROM AUTHOR]

In this work, X-ray microfluorescence with the synchrotron radiation technique was applied in the analysis of pigments found in decorative paintings in the sarcophagus of an Egyptian mummy. This female mummy, from the Roman Period, which was embalmed with the arms and legs swathed separately is considered one of the most important pieces of the Egyptian Collection from the National Museum (Rio de Janeiro, Brazil). The measurements were performed at the XRF beamline D09B of the Brazilian Synchrotron Light Laboratory (LNLS), using the white beam and a Si(Li) detector with resolution of 165 eV at 5.9 keV. The possible pigments found in the samples were: Egyptian blue, Egyptian green frit, green earth, verdigris, malachite, ochre, realgar, chalk, gypsum, bone white, ivory black and magnetite. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were applied to the results in order to verify if the samples belong to the same period of a linen wrapping fragment, whose provenance was well established. [ABSTRACT FROM AUTHOR]