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The great majority of nosocomial fungal infections, especially fungemias, are caused by yeasts, mostly of the genus Candida. In addition, such infections may be associated with intravascular catheters. In this study, 80 yeast strains were isolated from hospitalized children, being 59 from blood cultures and 21 from vascular catheter cultures. The prevalent species in both blood and catheter was C. parapsilosis (32.2% and 48.9%, respectively), followed by C. albicans (16.9% and 28.6%, respectively). Concerning enzyme production, 78.8% of the 80 isolates presented strong proteolytic activity but 78.8% showed no phospholipase activity. We also detected two prevalent killer biotypes: 511 and 888. Additionally, in five patients, it was possible to observe that the yeast species, killer biotype and proteolytic and phospholipase activity of blood and catheter were similar. In view of this, we suggest a transmission of nosocomial yeast infection from catheter to blood.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

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The specifity of gene encoding the ribotoxin protein in Aspergillus fumigatus was determined by PCR amplification of a portion of the gene. All A. fumigatus strains studied showed the presence of amplifiable ribotoxin product, while none of the other fungal species, with the exception of Aspergillus restrictus, showed this amplification product. Hence, this method may be used for rapid and specific identification of A. fumigatus.  相似文献   

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Species of Clostridium are widely distributed in the environment, inhabiting both human and animal gastrointestinal tracts. Clostridium difficile is an important pathogen associated with outbreaks of pseudomembranous colitis and other intestinal disorders, such as diarrhea. In this study, the prevalence of Clostridium spp. and C. difficile, from hospitalized children with acute diarrhea, was examined. These children were admitted to 3 different hospitals for over 12 months. Eighteen (20%) and 19 (21%) stool specimens from children with (90) and without (91) diarrhea respectively, were positive to clostridia. Only 10 C. difficile strains were detected in 5.5% of the stool samples of children with diarrhea. None healthy children (without diarrhea) harbored C. difficile. From these 10 C. difficile, 9 were considered as toxigenic and genotyped as tcdA+/tcdB+ or tcdA-/tcdB+, and 1 strain as nontoxigenic (tcdA-/tdcB-). They were detected by the citotoxicity on VERO cells and by the multiplex-polymerase chain reaction. Thirty clinical fecal extracts produced minor alterations on VERO cells. The presence of C. difficile as a probable agent of acute diarrhea is suggested in several countries, but in this study, the presence of these organisms was not significant. More studies will be necessary to evaluate the role of clostridia or C. difficile in diarrhoeal processes in children.  相似文献   

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The biochemical and serological characteristics, virulence properties, and genetic relatedness of Shiga toxin-producing Escherichia coli (STEC) strains isolated in S o Paulo, from April 1989 through March 1990, were determined. This is also the first report on clinic findings of human STEC infections in Brazil. The only three STEC strains identified in that period were lysine decarboxylase negative, belonged to serotype O111ac: non-motile, were Stx1 producers, carried the eae and astA genes, and 2 of them also presented the EHEC-hly sequence. The children carrying STEC were all boys, with less than two years old, and had no previous history of hospitalization. None of them presented blood in stools. Vomiting, cough and coryza were the most common clinical manifestations observed. Although the STEC strains were isolated during summer months, and presented similar phenotypic and genotypic characteristics, carbohydrate fermentation patterns and PFGE analysis suggested that these diarrheal episodes were not caused by a single clone.  相似文献   

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Infections by Cryptococcus strains other than C. neoformans have been detected in immunocompromised patients. Of these strains, three are considered human pathogens: C. albidus, C. laurenttii, and C. uniguttulatus. This study deals with the in vitro susceptibility of Cryptococcus to drugs such as amphotericin B, itraconazole, fluconazole, and 5-fluorocytosine. Environmental Cryptococcus isolates (50) distributed as follows: C. neoformans var. neoformans (16), C. albidus (17), C. laurentii (14), and C. uniguttulatus (3) were evaluated by the micro and macrodilution techniques, according to EUCAST and NCCLS recommendations, respectively. Considering both methodologies the respective minimal inhibitory concentrations (MIC) were 0.125 and 2 microg/ml for amphotericin B, 0.06 and 8 microg/ml for itraconazole, and 0.5 and more than 64 microg/ml for fluconazole and 5-fluorocytosine. Agreement percentages for the two methodologies were 100% for amphotericin B and fluconazole for all the strains tested. For itraconazole, the agreement percentage was 81.3% in the C. neoformans strain and 100% for all the others. All species had a agreement percentage of 94.1 to 100% when susceptibility to 5-fluorocytosine was tested. It is concluded that environmental isolates of C. neoformans var. neoformans, C. albidus, C. laurentii, and C. uniguttulatus may show high MICs against certain drugs, suggesting in vitro primary resistance to the antifungals tested.  相似文献   

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Visceral larva migrans syndrome by Toxocara affects mainly children between 2 and 5 years of age, it is generally asymptomatic, and the seroprevalence varies from 3 to 86% in different countries. A total of 399 schoolchildren from 14 public schools of the Butant? region, S?o Paulo city, Brazil, were evaluated by Toxocara serology (enzyme-linked immunosorbent assay). Epidemiological data to the Toxocara infection obtained from a protocol were submitted to multiple logistic regression analysis for a risk profile definition. Blood was collected on filter paper by finger puncture, with all samples tested in duplicate. Considering titers > or = 1/160 as positive, the seroprevalence obtained was 38.8%. Among infected children, the mean age was 9.4 years, with a similar distribution between genders. A significant association was observed with the presence of onychophagia, residence with a dirty backyard, living in a slum, previous wheezing episodes, school attended, and family income (p < 0.05). All data, except "living in a slum", were considered to be determinant of a risk profile for the acquisition of Toxocara infection. A monthly income > or = 5 minimum salaries represented a protective factor, although of low relevance. Toxocara eggs were found in at least one of the soil samples obtained from five schools, with high prevalence of Toxocara infections, indicating the frequent soil contamination by this agent.  相似文献   

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Faunal inventories are extremely important, especially when focused on neglected groups, such as echinoderms, and concentrated on areas under intense anthropic activity such as the SAo Sebastilo Channel in Brazil (23 degrees 41' - 23 degrees 54' S and 45 degrees 19' - 45 degrees 30' W). Intertidal and upper sublittoral zone collections were performed at five sites of the Channel's continental margin from May to August 2001. The rocky substrate down to 19 m deep was surveyed by snorkeling and SCUBA diving from August 2002 to May 2004, on both margins of the Channel: continental (14 sites) and insular (10 sites). We report a total of 38 species of echinoderms (one Crinoidea, nine Asteroidea, 13 Ophiuroidea, nine Echinoidea and six Holothuroidea). Seven of those species have been recorded here for the first time for the Channel (four Asteroidea, two Ophiuroidea and one Echinoidea).  相似文献   

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In the present study, 87 Staphylococcus aureus isolates obtained from milk samples of 87 cows with mastitis in 6 different municipal districts of 2 regions of Sao Paulo State, Brazil, were compared pheno- and genotypically. Pulsed-field gel electrophoresis (PFGE) analysis of the strains was performed, and PCR was carried out to detect genes for a number of staphylococcal cell surface proteins, exoproteins, and 3 classes of agr genes. Nine distinct S. aureus lineages (LA-LI) were identified by PFGE. The lineages LA and LE, which accounted together for 63 strains (72.2%), were prevalent and had been collected from all of the 6 municipal districts, indicating a broad geographic distribution of these lineages; LB, LC, LD, LF, LG, LH, and LI, however, were isolated sporadically and accounted for 24 strains (27.8%). Some characteristics, like penicillin resistance and the presence of cap8 and agr class II genes, were associated with the prevalent lineages (LA and LE), and penicillin susceptibility and the presence of cna and cap5 genes were associated with sporadic lineages. According to the present results, some S. aureus lineages possess a combination of genes that confer the propensity to cause and disseminate infection, and only a limited number of clones are responsible for the cases of bovine mastitis on the various farms.  相似文献   

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To determine the incidence of tinea capitis in São Paulo, Brazil, an investigation was performed in Private and Public Pediatrics Service involving 4,500 children from 0 to 15 years old during 5 years (1996–2000). Samples were taken from 132 children with suspected fungal infection of the scalp, for direct microscopy and culture. Tinea of scalp was mycologically confirmed in 112 patients (85%). Males were more affected than females in all age groups. Children below 8 years old accounted for more than 75% of the occurrences. Only three cases of tinea capitis were diagnosed in children from 12 to 15 years of age. Tinea capitis was prevalent in 103 cases (91.96%); inflammatory kerion type lesions were diagnosed in 9 patients (8.04%). Microsporum canis (70.5%) and Trichophyton tonsurans (23.2%) were the most common agents followed by T. mentagrophytes (3.6%), M. gypseum (1.8%) and T. rubrum (0.9%).  相似文献   

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Six species of bioluminescent agarics are described and illustrated from a single site in primary Atlantic Forest habitat in the Parque Estadual Turistico do Alto Ribeira, Sao Paulo State, Brazil. These include two new taxa of Mycena, viz. M. asterina and M. lucentipes. Luminescence in Mycena fera, M. singeri and M. discobasis is reported for the first time. In addition an undeterminable luminescent Mycena species is described and additional specimens of Gerronema viridilucens are documented. An accounting of known bioluminescent species of Mycena and a discussion of why they luminesce are presented.  相似文献   

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A total of 283 Salmonella Typhimurium strains isolated from cases of human infections and non human sources, were examined for antimicrobial susceptibility and the incidence of resistance was 38% and multiple resistance (to three or more antimicrobials) was 15%. All 43 multidrug-resistant strains (MDR) and 13 susceptible ones were characterized by phage typing and pulsed- field gel electrophoresis (PFGE). The strains encompassed 14 definitive phage types (DT), three were untypable (UT), and 18 atypicals or reaction does not conform (RDNC), which belonged to 21 PFGE patterns, A1-A21. The predominant phage types were DT49, DT193, and RDNC and two strains belonging to DT 104 and 104b were also identified. The most common PFGE patterns were A1 and A8. Analysis by PFGE and phage typing demonstrated that the most of the MDR were multiclonal and association among multiresistance, phage typing, and PFGE patterns was not so significant.  相似文献   

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The aim of this study was to investigate the naturally occurring bacteria from Culicidae larvae found in São Paulo state between 2006 and 2008 from the Tiete Ecological Park in the municipality of Caraguatatuba. Bacterial strains were obtained after surface sterilization of larvae followed by thermal treatment and incubation in bacteriological media under laboratory conditions. Identification was determined using cytomorphology, biochemical and physiological tests. Strains were characterized by qualitative evaluation of biological activity against Culicidae larvae, comparing protein profiles obtained by electrophoresis of crystal protoxins, electrophoresis of Lysinibacillus sphaericus isoenzymes, detection of the L2 fraction of Hemolytic BL enterotoxin and amplification of DNA using Multiplex-PCR to detect HBL, NHE, CytK, BceT and EntFM enterotoxins. The results obtained in this study demonstrated that the endosymbiotic bacterial diversity belonging to Bacillus and related genera associated with Culicidae larvae is limited to a number of species that does not vary throughout the seasons.  相似文献   

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Sheep are important in the epidemiology of Toxoplasma gondii infection but little is known of ovine toxoplasmosis in Brazil. Antibodies to T. gondii were assayed in sera of 495 sheep from 36 counties of S?o Paulo State, Brazil, using the modified agglutination test (MAT titer > or =1:25) and found in 120 (24.2%). Samples of brain, heart, and diaphragm of 82 seropositive sheep were pooled, digested in pepsin, and bioassayed in mice. Toxoplasma gondii was isolated from tissue homogenates of 16 sheep and the isolates were designated TgShBr1-16. Six of the 16 T. gondii isolates killed 100% of infected mice. Results indicate that asymptomatic sheep can harbor mouse-virulent T. gondii, and hence they can serve as a source of infection for humans.  相似文献   

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The present study reports a collection of Amblyomma spp. ticks in birds from several areas of the state of São Paulo, Brazil. A total of 568 tick specimens (404 larvae, 164 nymphs) were collected from 261 bird specimens. From these ticks, 204 (36%) specimens (94 larvae, 110 nymphs) were reared to the adult stage, being identified as Amblyomma longirostre (94 larvae, 90 nymphs), Amblyomma calcaratum (13 nymphs), Amblyomma nodosum (2 nymphs), and Amblyomma cajennense (5 nymphs). Additionally, 39 larvae reared to the nymphal stage and 8 nymphs that died before reaching the adult stage were identified as A. longirostre according to peculiar characters inherent to the nymphal stage of this species: scutum elongate, and hypostome pointed. The remaining 271 larvae and 46 nymphs were identified as Amblyomma sp. Ticks were collected from 51 species of birds distributed in 22 bird families and 6 orders. The order Passeriformes constituted the vast majority of the records, comprising 253 (97%) out of the 261 infested birds. Subadults of A. longirostre were identified from 35 species of Passeriformes, comprising 11 families (Cardinalidae, Dendrocolaptidae, Fringillidae, Furnariidae, Parulidae, Pipridae, Thamnophilidae, Thraupidae, Turdidae, Tyrannidae, and Vireonidae), and from 1 species of a non-passerine bird, a puffbird (Bucconidae). Subadults of A. calcaratum were identified from 5 species of Passeriformes, comprising 5 families (Cardinalinae, Conopophagidae, Pipridae, Thamnophilidae and Turdidae). Subadults of A. nodosum were identified from 2 species of Passeriformes, comprising two bird families (Thamnophilidae and Pipridae). Subadults of A. cajennense were identified from 2 species of non-passerine birds, belonging to 2 different orders (Ciconiiformes: Threskiornithidae, and Gruiformes: Cariamidae). Birds were usually infested by few ticks (mean infestation of 2.2 ticks per bird; range: 1–16). Currently, 82 bird species are known to be infested by immature stages of A. longirostre, with the vast majority [74 (90%)] being Passeriformes. Our results showed that Passeriformes seems to be primary hosts for subadult stages of A. longirostre, A. calcaratum, and A. nodosum. However, arboreal passerine birds seem to be the most important hosts for A. longirostre whereas ground-feeding passerine birds seem to be the most important for both A. calcaratum and A. nodosum. In contrast, the parasitism of birds by subadults of A. cajennense has been restricted to non-passerine birds.  相似文献   

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This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of S?o Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi), and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus) were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting fleas, whereas Rickettsia bellii was the only agent infecting ticks, but no animal or human blood was shown to contain rickettsial DNA. Testing animal and human sera by indirect immunofluorescence assay against four rickettsia antigens (R. rickettsii, R. parkeri, R. felis, and R. bellii), some opossum, dog, horse, and human sera reacted to R. rickettsii with titers at least four-fold higher than to the other three rickettsial antigens. These sera were considered to have a predominant antibody response to R. rickettsii. Using the same criteria, opossum, dog, and horse sera showed predominant antibody response to R. parkeri or a very closely related genotype. Our serological results suggest that both R. rickettsii and R. parkeri infected animals and/or humans in the studied areas.  相似文献   

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Particulate matter less than 10 microns aerodynamic diameter (PM10) is associated with adverse health effects including increased respiratory problems and mortality. PM10 is also associated with increases in cancer in some urban areas. Identification of toxic compounds in PM10 is a step toward estimating exposure to these compounds and evaluating their public health risk. However, the toxic compounds on PM10 are part of a highly complex mixture of compounds that makes chemical characterization difficult. Before this study, there has been little investigation of genotoxic compounds in particulate matter from Latin American cities. Here, both bioassay (mutagenicity) and chemical analyses were conducted with organic solvent extracts of PM10 collected from S?o Paulo, a major Brazilian city. Sequential extraction in dichloromethane (DCM) followed by acetone (ACE) yielded 20.3% and 10.2% of the total mass, respectively. Non-polar and moderately polar organic material solubilized in DCM. ACE extracted more polar organic species and some inorganic ions. Both extracts were fractionated separately using cyanopropyl-bonded silica chromatography with organic solvents of increasing polarity. The mass distribution among the fractions was measured. The mutagenic activity of the fractions was assayed using the microsuspension procedure with the Salmonella typhimurium tester strain TA98, with and without addition of metabolic enzymes (S9). The DCM extract had about four times higher mutagenic activity than the ACE extract. In general, addition of S9 resulted in an increase in mutagenicity of DCM fractions, but a decrease for the ACE extract. Most of the activity was concentrated in fractions in the mid-range of polarity within both the DCM and ACE extracts. The fractions were analyzed by gas chromatography with mass selective detection (GC/MS) without derivatization. The most mutagenic fractions in the DCM extract contained ketones, aldehydes, and quinolines. The most mutagenic ACE fraction had ketones, carboxylic acids, and aldehydes.  相似文献   

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