Diagnostic accuracy of semi-quantitative and quantitative culture techniques for the diagnosis of catheter-related infections in newborns and molecular typing of isolated microorganisms

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diversity of Staphylococcus species and prevalence of enterotoxin genes isolated from milk of healthy cows and cows with subclinical mastitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo dos fatores de virulência e resistência à oxacilina em Staphylococcus spp. isolados de aspirado traqueal de pacientes em ventilação mecânica internados em UTI

Patients that are mechanically ventilated in ICUs are constantly exposed to different pathogens, which present multiantibiotic resistance. Among these microorganisms, is MRSA (Meticillin-Resistant Staphylococcus aureus) considered to be a therapeutic challenge due to its resistance to β-lactam antibiotics. Therefore, this study proposed to identify species of Staphylococcus spp. isolated from mechanically ventilated patients in ICU, the gene mecA detection and the genes of the enterotoxins A (sea), B (seb), C (sec-1) and D (sed) in samples of S. aureus, as well as the phenotypic resistance determination to oxacillin using the disc-diffusion method with discs of oxacillin and cefoxitin. The samples collection occurred during in a period of 19 months, obtaining samples from 232 patients. A percentage of 39% (70) of Gram-positive cocci were found; which 82,8% (58) were identified as Staphylococcus spp,. among these, 75,8% (44) corresponded to S. aureus species and 47,7% were identified as MRSA. It was found resistance to both drugs in 31,8% of the S. aureus samples, 16 (36,3%) had the gene sea and 11 (25%) had the sec-1 gene. Among the coagulase-negative staphylococci obtained, the species most found was S. epidermidis, corresponding to 43% (6). The results revealed that one of the most important etiologic agents of VAP amid the Gram-positive cocci is the species S. aureus, with special attention to MRSA. The presence of enterotoxins genes in S. aureus did not showed determinant role in VAP, but the presence of these superantigens can contribute worsening the patient’s prognosis, since they are associated with intense inflammatory response

Biofilme estafilocócico: prevenção, detecção da produção e determinação do perfil de resistência a antimicrobianos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ocorrência de mastite subclínica ovina durante duas lactações consecutivas em rebanho da raça Santa Inês

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Staphylococcus epidermidis and Staphylococcus haemolyticus: molecular detection of cytotoxin and enterotoxin genes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detecção de genes de entrotoxinas de Staphylococcus aureus e estafilococos coagulase negativos isolados de leite bovino e de tanques de refrigeração comunitários procedentes de pequenas propriedades da região de Bauru-SP

Pós-graduação em Medicina Veterinária - FMVZ

Contagem de células somáticas para o diagnóstico da mastite subclínica ovina em diferentes raças em dois períodos de lactação

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Staphylococcal enterotoxins: molecular aspects and detection methods

Members of the Staphylococcus genus, especially Staphylococcus aureus, are the most common pathogens found in hospitals and in community-acquired infections. Some of their pathogenicity is associated with enzyme and toxin production. Until recently, S. aureus was the most studied species in the genus; however, in last few years, the rise of infections caused by coagulase-negative staphylococci has pointed out the need for further studies on virulence factors that have not yet been completely elucidated so as to better characterize the pathogenic potential of this group of microorganisms. Several staphylococcal species produce enterotoxins, a family of related proteins responsible for many diseases, such as the toxic-shock syndrome, septicemia and food poisoning. To this date, 23 different enterotoxin types have been identified besides toxic-shock syndrome toxin-1 (TSST-1), and they can be divided into five phylogenetic groups. The mechanism of action of these toxins includes superantigen activity and emetic properties, which can lead to biological effects of infection. Various methods can detect genes that encode enterotoxins and their production. Molecular methods are the most frequently used at present. This review article has the objective to describe aspects related to the classification, structure and regulation of enterotoxins and toxic-shock syndrome toxin-1 detection methods.

First report of vancomycin-resistant staphylococci isolated from healthy carriers in Brazil

Reduced susceptibility or resistance to vancomycin has been reported among clinical isolates of staphylococci in previous studies. In the present study we report on the isolation of four vancomycin-resistant staphylococcal strains from healthy carriers inside and outside the hospital environment. These carriers did not receive treatment with any antibiotic. All coagulase-negative staphylococcal strains showed variable levels of resistance to several antimicrobial agents, including oxacillin, and unstable resistance to vancomycin, with decreased vancomycin MICs (<4 mg/liter) after 10 days of passage in a nonselective medium. However, exposure of these revertants to vancomycin selected staphylococcal strains resistant to vancomycin at very high frequencies (10(-2) and 10(-3)). The vancomycin resistance in these staphylococcal strains was not mediated by the van gene. The cell wall of the staphylococcal strains studied became thickest after culture in medium containing vancomycin, and the differences in cell wall thickness were statistically significant (P < 0.001). Thus, the thickening of the cell wall in these staphylococcal strains may be an important contributor to vancomycin resistance.

Beta-lactamase detection in Staphylococcus aureus and coagulase-negative Staphylococcus isolated from bovine mastitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Treatment with Azadirachta indica in diabetic pregnant rats: Negative effects on maternal outcome

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)