Caracterização fenotípica e molecular das espécies fúngicas causadoras de peritonites em pacientes submetidos à diálise peritoneal ambulatorial continua do Hospital das Clínicas da UNESP, Botucatu

As peritonites são sérias e frequentes complicações em pacientes submetidos à terapia de reposição renal, principalmente na diálise peritoneal ambulatorial contínua (CAPD, “continuous ambulatory peritoneal dialysis”). As infecções fúngicas, embora menos frequentes que as bacterianas, estão associadas a uma maior taxa de morbidade e mortalidade, e normalmente tornam impossíveis a CAPD, devido à necessidade de remoção do cateter. Este trabalho visou caracterizar e identificar as peritonites fúngicas com o uso de métodos morfofisiológicos e moleculares, além de avaliar seus perfis de sensibilidade e produção de biofilme in vitro em pacientes submetidos à CAPD do Hospital das Clínicas da Faculdade de Medicina de Botucatu. Foram avaliados trinta isolados de leveduras obtidos de episódios distintos de peritonites, que foram identificados por métodos morfofisiológicos (CHROMagar e auxanograma) e moleculares, tais como o sequenciamento de rDNA, perfil de restrição do gene SADH e padrão do intron do grupo I. Foram também realizados o perfil de sensibilidade antifúngica para as drogas anfotericina B, fluconazol, voriconazol e caspofungina pela técnica de microdiluição em caldo, seguindo o protocolo do CLSI M27-A3 e a produção de biofilme utilizando-se discos de silicone em reação com XTT (sal de tetrazol). Dos 30 isolados de leveduras, observou-se que as espécies de Candida parapsilosis foram as predominantes (n=10), seguida de Candida albicans (n=7), Candida tropicalis (n=6), Candida orthopsilosis (n=5), Candida guilliermondii (n=1) e Kodamaea ohmeri (n=1). Dentre os isolados de C. albicans, caracterizados pelo perfil de intron do grupo I, observou-se predomínio de genótipos do grupo A (n=5) e também a ocorrência de genótipos do grupo B (n=2). Todos os isolados foram sensíveis ao voriconazol e caspofungina, amostras de C.orthopsilosis (n=5), K.ohmeri (n=1), C.guilliermondii (n=1) e C. albicans (n=1) ..

DNA damage in patients who underwent minimally invasive surgery under inhalation or intravenous anesthesia

Recent studies have demonstrated the genotoxicity of anesthetics in patients who have undergone surgery and in personnel who are occupationally exposed to anesthetics. However, these findings are controversial. Herein, we used the comet assay (single-cell gel electrophoresis) to investigate the genotoxic effects of two volatile compounds [isoflurane (ISF) and sevoflurane (SVF)] that are used in inhalation anesthesia, and of one intravenous (iv) anesthetic compound [propofol (PF)]. The groups consisted of 45 patients who underwent minimally invasive surgery that lasted at least 2 h. Patients were classified as physical status I using the criteria of the American Society of Anesthesiologists (ASA) and were randomly allocated to receive ISF. SVF or PF anesthesia. Venous blood samples were collected at three time points as follows: before the premedication and the induction of anesthesia (T(0)); 2 h after the beginning of anesthesia (T(1)); and on the day following surgery (T(2)). DNA damage (strand breaks and alkali-labile sites) was evaluated in peripheral blood lymphocytes. For each patient, one hundred nucleoids were analyzed per time point using a semi-automated image system. Patients did not differ with respect to their demographic characteristics, the duration of surgery, or the total doses of intraoperative drugs. The amount of DNA damage was not different among the three groups before anesthesia (T(0)). No statistically significant (p > 0.05) increase in DNA damage was detected during (T(1)) or after anesthesia (T(2)) using three different protocols (ISF, SVF or PF). In conclusion, general anesthesia with inhaled ISF and SVF or iv PF did not induce DNA strand breaks or alkali-labile sites in peripheral lymphocytes. Therefore, our results show that the genotoxic risk of these anesthetics, for healthy patients undergoing minimally invasive otorhinological surgery, is low or even absent. (C) 2011 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Evolution and Application of Inteins in Candida species: a Review

Inteins are invasive intervening sequences that perform an autocatalytic splicing from their host proteins. Among eukaryotes, these elements are present in many fungal species, including those considered opportunistic or primary pathogens, such as Candida spp. Here we reviewed and updated the list of Candida species containing inteins in the genes VMA, THRRS and GLT1 and pointed out the importance of these elements as molecular markers for molecular epidemiological researches and species-specific diagnosis, since the presence, as well as the size of these inteins, is polymorphic among the different species. Although absent in Candida albicans, these elements are present in different sizes, in some environmental Candida spp. and also in most of the non-albicans Candida spp. considered emergent opportunistic pathogens. Besides, the possible role of these inteins in yeast physiology was also discussed in the light of the recent findings on the importance of these elements as post-translational modulators of gene expression, reinforcing their relevance as alternative therapeutic targets for the treatment of non-albicans Candida infections, because, once the splicing of an intein is inhibited, its host protein, which is usually a housekeeping protein, becomes nonfunctional

Genotoxicity, cytotoxicity and gene expression in patients undergoing elective surgery under isoflurane anaesthesia

There are numerous studies reporting on the effects of inhalation anaesthesia in cells of exposed individuals but not much is known about the ability of isoflurane (ISF) to induce oxidative DNA damage. However, surgery is often associated with a temporary perioperative immunological alteration, and some volatile anaesthetics seem to contribute to a transient lymphocytopenia after surgery. We conducted a study to evaluate a possible genotoxic effect, including oxidative DNA damage, and apoptosis in peripheral lymphocytes of 20 patients American Society of Anaesthesiologists physical status I undergoing minor elective surgery lasting at least 120 min, under anaesthesia with ISF. We also investigated the expression of several genes in blood cells. Blood samples were collected at three time points: before anaesthesia (T(1)), 2 h after the beginning of anaesthesia (T(2)) and on the first post-operative day (T(3)). General DNA damage and oxidised bases (Fpg and endo III-sites) in blood lymphocytes were evaluated using the comet assay. Lymphocytes were phenotyped and apoptosis was evaluated by flow cytometry. In addition, expressions of hOGG1 and XRCC1, genes involved in DNA repair, and BCL2, a gene related to apoptosis, were assessed by quantitative real-time polymerase chain reaction. Results showed no statistically significant difference in the level of DNA damage and oxidised bases among the three sampling times. Anaesthesia with ISF did not increase the percentage of cells in early or late apoptosis in cytotoxic or helper T lymphocytes. Lower hOGG1 and BCL2 expressions were detected at T3 in comparison to the other two previous time points, and there was significantly lower expression of XRCC1 at T3 in relation to T2. In conclusion, the exposure to ISF did not result in genotoxicity and cytotoxicity in lymphocytes and in toxicogenomic effect in leukocytes, although DNA repair and apoptosis-related genes were down-regulated on the first post-operative day.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq