Cryptococcus neoformans is an environmental encapsulated yeast that behaves as an opportunistic pathogen in immunocompromised individuals. The capsule is the main virulence factor of this pathogen. This structure is highly dynamic, and it can change its size and structure according to the environmental conditions. During infection, C. neoformans significantly enlarges the size of the capsule by the addition of new polysaccharide. It is believed that capsule growth is an energy-cost process, but this aspect has never been addressed. In this work, we have evaluated the role of mitochondrial activity on capsule growth using specific inhibitors of the electron respiratory chain. We observed that capsule growth was impaired in the presence of inhibitors of the respiratory chain as salicylhydroxamic acid or antimycin A. Furthermore, capsule growth correlated with an increase of the mitochondrial membrane potential and higher production of reactive oxygen species. Our results confirm that capsule growth depends on mitochondrial activity, and open new insights to understand the regulation of this process.

The data presented herein confirm the foodborne disease outbreak. They also allowed for the identification of the source of infection, and suggest that products from poultry are potential reservoirs for this serotype, reinforcing the importance of warning consumers about the danger of possible contamination.

A pesquisa de Pseudomonas aeruginosa foi realizada em amostras de água tratada utilizada na solução de diálise de oito Unidades de Terapia Renal Substitutiva (UTRS) em quatro municípios do noroeste do estado de São Paulo e o perfil de resistência aos agentes antimicrobianos das cepas isoladas foi avaliado por teste de sensibilidade (TSA). Entre 2000 e 2009 foram analisadas 508 amostras seguindo-se a metodologia descrita no Standard Methods for the Examination of Water and Wastewater (2005) e 43 (8,5%) evidenciaram contaminação por P. aeruginosa. Dessas amostras, 55,8%, 23,3% e 20,9% foram, respectivamente, oriundas da sala branca, ponto de pós-osmose/ deionizador e sala amarela das diferentes UTRS. A frequência de isolamento da bactéria foi maior em amostras da UTRS A (53,5%) e em 2004 houve a detecção de maior número de amostras contaminadas (16,7%). Dos 43 isolados, 38 foram analisados pelo TSA, sendo identificadas resistência intermediária a gentamicina em um (2,6%) e resistência a aztreonam e ticarcilina/ácido clavulânico em outro isolado (2,6%). Pelas implicações da P. aeruginosa em saúde pública, sua investigação no monitoramento de qualidade da água para diálise constitui medida necessária e sua ocorrência indica as possíveis deficiências no controle da rede de distribuição da água.

Introduction: KPC and NDM carbapenemases production is an important enzymatic mechanism of resistance to carbapenens in bacteria belonging to the Enterobacteriaceae family. These enzymes degrade virtually all beta-lactam antibiotics and are encoded by the blaKPC and blaNDM genes, which can be in mobile genetic elements such as plasmids and transposons. Objectives: This study evaluated the positivity rate of the presence of blaKPC and blaNDM genes in carbapenem-resistant enterobacteria received at the Instituto Adolfo Lutz (IAL) of São José do Rio Preto, Brazil and determined the epidemiological data related to the patients whose isolates were recovered. Methods: From June 2015 to April 2019, bacterial isolates were obtained from different hospitals located in five municipalities in São José do Rio Preto region. In the bacteriology and molecular biology laboratory, DNA extraction and real-time PCR were performed to investigate the blaKPC and blaNDM genes. Afterwards, epidemiological data were surveyed such as the municipality of origin, age, and gender of the patients whose bacterial isolates were recovered. Results: A total of 934 enterobacteria isolates were recovered from the different hospitals. Of these; 93.4% were positive for blaKPC, with 96.3%, 1.85%, and 1.85% of the isolates belonged to the Klebsiella genus, Enterobacter genus, and Escherichia coli species, respectively. Also, 52.5% and 84.4% of the isolates were obtained from women and elderly patients, respectively. The blaNDM gene was detected only in three isolates, two of which originated from surveillance cultures. Conclusion: Therefore, KPC-producing enterobacteria are widespread in all health units of the five municipalities that were studied, suggesting that the blaKPC-carrying Klebsiella sp. isolates may be endemic in these institutions. Additionally, there is a significant role of surveillance cultures in preventing the spread of resistance genes, as observed for blaNDM in this study.