829 resultados para Fungal strain


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Coccidioidomycosis is a systemic mycosis, endemic in arid areas of the American continent. The rat was employed as an experimental host, since it had been shown to reproduce human lesions and present a chronic course of disease with granulomas mainly restricted to lungs. Given the influence of immunosuppressive therapy on the clinical course of human coccidioidomycosis, we studied the effect of cyclophosphamide (CY) in the experimental rat model. Accordingly, animals were inoculated with 400 Coccidioides immitis arthroconidia of the Acosta strain, by intracardiacal route. As single CY doses failed to alter the course of disease, three schedules were used: A) 4 daily doses of 20 mg/kg each, prior to C. immitis inoculation; B) 4 similar daily doses after infection; and C); 6 doses of 20 mg/kg each, given from day +1 to +4, then on days +8 and +9, post infection (pi), taking day 0 as the time of fungal inoculation. The first two schedules inhibited antibody formation up to day 28 pi, without modifying cellular response to coccidioidin as measured by foodpad swelling. Initially, there was greater fungal spread than in controls receiving C. immitis alone, which proved self-limiting in the latter. In contrast, schedule C led to 559r mortality, with both humoral and cellular response abrogation, accompanied by extensive C. immitis dissemination. Histology disclosed significant alterations, such as the persistence of primary infection sporangia, corresponding to the acute stage of coccidioidomycosis in the absence of granuloma development. Therefore, the observed depression in cellular immunity seems responsible for the lack of inflammatory reaction capable of restricting sporangia proliferation in tissues which, in turn, enhances pathogen spread and mortality rate.

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Measurements in civil engineering load tests usually require considerable time and complex procedures. Therefore, measurements are usually constrained by the number of sensors resulting in a restricted monitored area. Image processing analysis is an alternative way that enables the measurement of the complete area of interest with a simple and effective setup. In this article photo sequences taken during load displacement tests were captured by a digital camera and processed with image correlation algorithms. Three different image processing algorithms were used with real images taken from tests using specimens of PVC and Plexiglas. The data obtained from the image processing algorithms were also compared with the data from physical sensors. A complete displacement and strain map were obtained. Results show that the accuracy of the measurements obtained by photogrammetry is equivalent to that from the physical sensors but with much less equipment and fewer setup requirements. © 2015Computer-Aided Civil and Infrastructure Engineering.

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In the São Paulo State, Brazil, where the Biomphalaria tenagophila is the intermediate host, the Ribeira Valley is an important endemic schistosomiasis mansoni area. During last eleven years there has been intense control measures focusing on schistosomiasis. The efforts have been concentrated in the municipalities of Pedro de Toledo and Itariri. We determined the susceptibility of B. tenagophila to sympatric strain of S. mansoni, both recently isolated from Itariri field. In 1988, this strain was isolated and maintained in the experimental model: Swiss mice - sympatric B. tenagophila. The second generation of the worm was evaluated. The snail were divided in the three groups of 60 snails each. One group was exposed to 1 miracidium and other to 10. The third group was the control. The mortality and the shedding of cercariae were checked during 78 days. After that, the positive snails were observed until they ceased to shed cercariae. The exposed molluscs showed mortality rates of 23% and 31% and infection indexes were of 8% and 60% to 1 and 10 miracidia respectively. The mortality was of 22% in the control group. The periods of shedding cercariae in the two groups were 82 and 104 days. We can conclude that B. tenagophila is an effective intermediate host to the sympatric strain of S. mansoni sympatric strain

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In slaughterhouses, the biological risk is present not only from the direct or indirect contact with animal matter, but also from the exposure to bioaerosols. Fungal contamination was already reported from the floors and walls of slaughterhouses. This study intends to assess fungal contamination by cultural and molecular methods in poultry, swine/bovine and large animal slaughterhouses. Air samples were collected through an impaction method, while surface samples were collected by the swabbing method and subjected to further macro- and micro-scopic observations. In addition, we collected air samples using the impinger method in order to perform real-time quantitative PCR (qPCR) amplification of genes from specific fungal species, namely A. flavus, A. fumigatus and A. ochraceus complexes. Poultry and swine/bovine slaughterhouses presented each two sampling sites that surpass the guideline of 150 CFU/m3. Scopulariopsis candida was the most frequently isolated (59.5%) in poultry slaughterhouse air; Cladosporium sp. (45.7%) in the swine/bovine slaughterhouse; and Penicillium sp. (80.8%) in the large animal slaughterhouse. Molecular tools successfully amplified DNA from the A. fumigatus complex in six sampling sites where the presence of this fungal species was not identified by conventional methods. This study besides suggesting the indicators that are representative of harmful fungal contamination, also indicates a strategy as a protocol to ensure a proper characterization of fungal occupational exposure.

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Yeast forms of five strains of Paracoccidioides brasiliensis (SN, 2, 18, 192 and JT- 1) were cultured in a synthetic medium for obtaining methylic antigens. These antigens were lyophilized and studied for each strain, to determine their partial biochemical composition, through measurements of total lipid, protein and carbohydrate contents. Lipids of methylic antigens were purified and analysed for sterols, phospholipids, glycolipids, li-poproteins, and partial characterization of sterols. Significant differences were found among antigenic preparations derived from distinct P. brasiliensis strains, in relation to the quantitative determinations. On the other hand, sterol analysis revealed the presence of ergosterol, lanosterol and squalene in all samples. The diversity verified in the biochemical characteristics of antigens derived from different P. brasiliensis strains, confirm the need of using a pool of fungal samples in order to produce antigen preparations for serological procedures without hampering their sensitivity.

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BACKGROUNDWhile the pharmaceutical industry keeps an eye on plasmid DNA production for new generation gene therapies, real-time monitoring techniques for plasmid bioproduction are as yet unavailable. This work shows the possibility of in situ monitoring of plasmid production in Escherichia coli cultures using a near infrared (NIR) fiber optic probe. RESULTSPartial least squares (PLS) regression models based on the NIR spectra were developed for predicting bioprocess critical variables such as the concentrations of biomass, plasmid, carbon sources (glucose and glycerol) and acetate. In order to achieve robust models able to predict the performance of plasmid production processes, independently of the composition of the cultivation medium, cultivation strategy (batch versus fed-batch) and E. coli strain used, three strategies were adopted, using: (i) E. coliDH5 cultures conducted under different media compositions and culture strategies (batch and fed-batch); (ii) engineered E. coli strains, MG1655endArecApgi and MG1655endArecA, grown on the same medium and culture strategy; (iii) diverse E. coli strains, over batch and fed-batch cultivations and using different media compositions. PLS models showed high accuracy for predicting all variables in the three groups of cultures. CONCLUSIONNIR spectroscopy combined with PLS modeling provides a fast, inexpensive and contamination-free technique to accurately monitoring plasmid bioprocesses in real time, independently of the medium composition, cultivation strategy and the E. coli strain used.

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A cepa WSL (Wild São Lorenço) de T. cruzi, isolada de um cobaio proveniente de São Lorenço da Mata (Nordeste do Brasil) foi caracterizada através da análise do seu comportamento morfobiológico e perfil isoenzimático. Para o estudo do comportamento morfobiológico, tripomastigotas sanguíneos (1 x 10 5) da cepa WSL foram inoculados por via intraperitonal em camundongos albinos Swiss. Como controle a cepa Y (Tipo I) foi usada. Durante o curso da infecção os seguintes parâmetros foram analisados: parasitemia, mortalidade, morfologia dos parasitas no sangue periférico e tropismo tissular. O perfil isoenzimático foi analisado em relação às enzimas ALAT, GPI e PGM usando como controle de referência as cepas Peruana (Tipo I), 21SF (Tipo II) e Colombiana (Tipo III). A cepa WSL apresentou as seguintes características biológicas: 1) multiplicação lenta e pico parasitêmico entre 21 - 25 dias pós-infecção; 2) mortalidade de 3,3% 40 dias pós-infecção; 3) predominância de formas largas no sangue periférico e 4) miotropismo com predominante envolvimento cardíaco. A análise isoenzimática mostrou um padrão de zimodema 2 (Z2) que corresponde às cepas biológicas Tipo II. Os resultados mostram que a cepa WSL apresenta baixa virulência e patogenicidade.

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In this paper we report a eight-year prospective study designed to further characterize incidence, epidemiology, specific syndromes, treatment and prognosis associated with fungal infections in neutropenic patients. During the study period 30 fungal infections were diagnosed in 30 patients among 313 episodes of fever and neutropenia (10%). There were 15 cases of candidiasis, 5 pulmonary aspergillosis, 3 sinusitis by Aspergillus fumigatus, 5 infections by Fusarium sp., one infection by Trichosporon sp., and one infection due to Rhodotorula rubra. Blood cultures were positive in 18 cases (60%). The predisposing factors for fungal infection in multivariate analysis were the presence of central venous catheter (p<0.001), longer duration of profound (<100/mm³) neutropenia (p<0.001), the use of corticosteroids (p<0.001), gram-positive bacteremia (p=0.002) and younger age (p=0.03). In multivariate analysis only recovery of the neutropenia (p<0.001) was associated with good prognosis whereas the diagnosis of infection by Fusarium sp. (p=0.006) was strongly associated with a poor outcome. The death rate was 43%. There was no statistically significant difference in the death rate between patients who did receive (52%) or did not receive (50%) antifungal treatment. Identifying patients at risk, specific syndromes and prognostic factors may help to reduce the high mortality associated with disseminated fungal infections in neutropenic patients.

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A strain of Schistosoma mansoni (R1) was isolated from patient previously submitted to four treatments with oxamniquine, and to another one with praziquantel. The results obtained with chemotherapeutic test, by using oxamniquine in mice infected with the strains R1 and LE (standard), showed an evident resistance to the drug in worms of the strain R1. Thus, at the dose of 250 mg/kg oxamniquine, all mice (17) infected with the LE strain did not show surviving worms, whereas 12 out of 17 mice infected with the R1 strain presented surviving worms. At the dose of 200 mg/kg, the LE strain showed recovery rates of 1.06% and 20.58%, whereas the R1 strain presented 18.57% and 61.14%, for male and female worms, respectively. At the dose of 100 mg/kg, the recovery of male worms was 2.6% for the LE strain, and 29.9% for the R1 strain. At the same dose, the recovery of females did not show statistically significant differences between the two strains (LE = 76.38%, R1 = 79.12%). Praziquantel showed similar antischistosomal activity against both studied strains, when administered at the dose of 500 mg/kg

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Pentachlorophenol (PCP) bioremediation by the fungal strains amongst the cork- colonising community has not yet been analysed. In this paper, the co- and direct metabolism of PCP by each of the 17 fungal species selected from this community were studied. Using hierarchical data analysis, the isolates were ranked by their PCP bioremediation potential. Fifteen isolates were able to degrade PCP under co-metabolic conditions, and surprisingly Chrysonilia sitophila, Trichoderma longibrachiatum, Mucor plumbeus, Penicillium janczewskii and P. glandicola were able to directly metabolise PCP, leading to its complete depletion from media. PCP degradation intermediates are preliminarily discussed. Data emphasise the signiWcance of these fungi to have an interesting potential to be used in PCP bioremediation processes.

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Giardia duodenalis isolates from asymptomatic or symptomatic patients and from animals present similarities and differences in the protein composition, antigenic profile, pattern of proteases and isoenzymes, as well as in nucleic acids analysis. In the present overview, these differences and similarities are reviewed with emphasis in the host-parasite interplay and possible mechanisms of virulence of the protozoon.

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A case of atypical disseminated cutaneous histoplasmosis in a five-year old, otherwise healthy child, native and resident in São Paulo metropolitan area is reported. Cutaneous lesions were clinically atypical. Histologic examination disclosed a granulomatous reaction but no fungal structures could be demonstrated by specific staining nor by immunohistochemical reaction. The fungus was isolated from biopsy material on two different occasions, confirming diagnosis of an unusual fungal infection. The fungus, originally thought to be a Sepedonium sp. due to the large sized, hyaline or brownish colored tuberculated macroconidia and to lack of dimorphism (yeast form at 37 °C) produce H and M antigens, visualized by the immunodiffusion with rabbit anti-Histoplasma capsulatum hyperimmune serum. Patient’s serum sample was non reactive with H. capsulatum antigen by immunodiffusion, counterimmunoelectrophoresis and complement fixation tests, and immunoenzymatic assay failed to detect the specific circulating antigen. This serum was tested negative by double immunodiffusion when antigen obtained from one of the isolated samples was used. Both cultures were sent to Dr. Leo Kaufman, Ph.D. (Mycoses Immunodiagnostic Laboratory, CDC-Atlanta/USA), who identified them as H. capsulatum by the exoantigen and gen-probe tests. Both clinic and mycologic characteristics of the present case were atypical, suggesting the fungus isolated is an “aberrant variant” of H. capsulatum var. capsulatum, as described by SUTTON et al. in 199719. Treatment with itraconazole 100 mg/day led to cure within 90 days

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