In order to survive inside macrophages, Salmonella produces a series of proteins encoded by genes within Salmonella pathogenicity island 2 (SPI-2). In the present study, we report that Fur, a central regulator of iron utilization, negatively controls the expression of SPI-2 genes. Time course analysis of SPI-2 expression after the entry of Salmonella into macrophages revealed that SPI-2 genes a...

The tremendous success of Staphylococcus aureus as a pathogen is due to the controlled expression of a diverse array of virulence factors. The effects of host environments on the expression of virulence factors and the mechanisms by which S. aureus adapts to colonize distinct host tissues are largely unknown. Vertebrates have evolved to sequester nutrient iron from invading bacteria, and iron a...

A goal of animal movement analysis is to reveal behavioural mechanisms by which organisms utilize complex and variable environments. Statistical analysis of movement data is complicated by the fact that the data are multidimensional, autocorrelated and often marked by error and irregular measurement intervals or gappiness. Furthermore, movement data reflect behaviours that are themselves hetero...

Due to its complexity, in combination with a lack of scientific reports, fur-chewing became one of the most challenging behavioral problems common to captive chinchillas. In the last years, the hypothesis that fur-chewing is an abnormal repetitive behavior and that stress plays a role in its development and performance has arisen. Here, we investigated whether a relationship existed between the...

The invasion of intestinal epithelial cells by Salmonella enterica serovar Typhimurium is mediated by a type III secretion system (T3SS) encoded on Salmonella pathogenicity island 1 (SPI1). Expression of the SPI1 T3SS is tightly regulated by the combined action of HilC, HilD, and RtsA, three AraC family members that can independently activate hilA, which encodes the direct regulator of the SPI1...

The Brazilian South coast seasonally hosts numerous marine species, observed particularly during winter months. Some animals, including fur seals, are found dead or debilitated along the shore and may harbor potential pathogens within their microbiota. In the present study, a metagenomic approach was performed to evaluate the viral diversity in feces of fur seals found deceased along the coast ...

The present study evaluates whether intravesical 5-fluorouridine (FUR), a potent fluorinated pyrimidine, is effective against bladder cancer. The tissue and plasma pharmacokinetics of i.v. and intravesical FUR were studied in dogs to determine the tissue targeting advantage by the intravesical route. The i.v. study used a bolus FUR dose of 4 mg/kg, which is tolerated in humans. The disposition ...

Feeding performance studies can address questions relevant to feeding ecology and evolution. Our current understanding of feeding mechanisms for aquatic mammals is poor. Therefore, we characterized the feeding kinematics and performance of five Steller sea lions (Eumetopias jubatus) and six northern fur seals (Callorhinus ursinus). We tested the hypotheses that both species use suction as their...

Previously unresolved problems in the populations studies of the Pribilof fur seal are reviewed. The tagging estimates of fur seal pups may have been biased by tag mortality and hence the apparent year class fluctuations after 1952 may be unreal. A set of cumulative estimates are given for the number of pups born in each year since 1950. These cumulative estimates depend on the estimate of the ...

Shigella flexneri requires iron for survival, and the genes for iron uptake and homeostasis are regulated by the Fur protein. Microarrays were used to identify genes regulated by Fur and to study the physiological effects of iron availability in S. flexneri. These assays showed that the expression of genes involved in iron acquisition and acid response was induced by low-iron availability and b...