16 research outputs found

    Quantitative analysis of Terminal Restriction Fragment Length Polymorphism (T-RFLP) microbial community profiles: peak height data showed to be more reproducible than peak area Análise quantitativa de perfis de T-RFLP de comunidades microbianas: dados de altura de picos mostraram-se mais reprodutíveis do que os de área

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    Terminal Restriction Fragment Length Polymorphism (T-RFLP) is a culture-independent fingerprinting method for microbial community analysis. Profiles generated by an automated electrophoresis system can be analysed quantitatively using either peak height or peak area data. Statistical testing demontrated that peak height data showed to be more reproducible than peak area data.<br>Terminal Restriction Fragment Length Polymorphism (T-RFLP) é um método molecular, independente de cultivo, para análise de comunidades microbianas. Perfis gerados por um sistema automatizado de eletroforese podem ser analisados quantitativamente usando dados de altura ou área dos picos. Os dados de altura mostraram-se mais reprodutíveis do que os de área

    Toxicity-directed approach of polyester manufacturing industry wastewater provides useful information for conducting treatability studies

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    A broader characterization of industrial wastewaters, especially in respect to hazardous compounds and their potential toxicity, is often necessary in order to determine the best practical treatment (or pretreatment) technology available to reduce the discharge of harmful pollutants to the environment or publicly owned treatment works. Using a toxicity-directed approach, this paper sets the base for a rational treatability study of polyester resin manufacturing. Relevant physical and chemical characteristics were determined. Respirometry was used for toxicity reduction evaluation after physical and chemical effluent fractionation. Of all the procedures investigated, only air stripping was significantly effective in reducing wastewater toxicity. Air stripping in pH 7 reduced toxicity in 18.2%, while in pH 11 a toxicity reduction of 62.5% was observed. Results indicated that toxicants responsible for the most significant fraction of the effluent`s instantaneous toxic effect to unadapted activated sludge were organic compounds poorly or not volatilized in acid conditions. These results led to useful directions for conducting treatability studies which will be grounded on actual effluent properties rather than empirical or based on the rare specific data on this kind of industrial wastewater. (C) 2008 Elsevier B.V. All rights reserved.Coordination of Superior Level Staff Perfectioning (CAPES)Education Ministry of Brazi

    Human-Associated \u3cem\u3eBacteroides\u3c/em\u3e spp. and Human Polyomaviruses as Microbial Source Tracking Markers in Hawaii

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    Identification of sources of fecal contaminants is needed to (i) determine the health risk associated with recreational water use and (ii) implement appropriate management practices to mitigate this risk and protect the environment. This study evaluated human-associated Bacteroides spp. (HF183TaqMan) and human polyomavirus (HPyV) markers for host sensitivity and specificity using human and animal fecal samples collected in Hawaii. The decay rates of those markers and indicator bacteria were identified in marine and freshwater microcosms exposed and not exposed to sunlight, followed by field testing of the usability of the molecular markers. Both markers were strongly associated with sewage, although the cross-reactivity of the HF183TaqMan (also present in 82% of canine [n = 11], 30% of mongoose [n = 10], and 10% of feline [n = 10] samples) needs to be considered. Concentrations of HF183TaqMan in human fecal samples exceeded those in cross-reactive animals at least 1,000-fold. In the absence of sunlight, the decay rates of both markers were comparable to the die-off rates of enterococci in experimental freshwater and marine water microcosms. However, in sunlight, the decay rates of both markers were significantly lower than the decay rate of enterococci. While both markers have their individual limitations in terms of sensitivity and specificity, these limitations can be mitigated by using both markers simultaneously; ergo, this study supports the concurrent use of HF183TaqMan and HPyV markers for the detection of sewage contamination in coastal and inland waters in Hawaii. IMPORTANCE: This study represents an in-depth characterization of microbial source tracking (MST) markers in Hawaii. The distribution and concentrations of HF183TaqMan and HPyV markers in human and animal fecal samples and in wastewater, coupled with decay data obtained from sunlight-exposed and unexposed microcosms, support the concurrent application of HF183TaqMan and HPyV markers for sewage contamination detection in Hawaii waters. Both markers are more conservative and more specific markers of sewage than fecal indicator bacteria (enterococci and Escherichia coli). Analysis of HF183TaqMan (or newer derivatives) is recommended for inclusion in future epidemiological studies concerned with beach water quality, while better concentration techniques are needed for HPyV. Such epidemiological studies can be used to develop new recreational water quality criteria, which will provide direct information on the absence or presence of sewage contamination in water samples as well as reliable measurements of the risk of waterborne disease transmission to swimmers

    Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque: a prospective study Chlamydia pneumoniae e placa aterosclerótica sintomática de carótida: um estudo prospectivo

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    OBJECTIVE: To investigate the possible link between symptomatic carotid atherosclerotic plaque and Chlamydia pneumoniae. BACKGROUND: Recently, several studies have demonstrated that there may be a possible link between Chlamydia pneumonia and carotid atherosclerosis, however the real role of Chlamydia pneumoniae is not completely understood. METHOD: This is a prospective study with a total of 52 patients analyzed. All patients had been submitted to endarterectomy, and had suffered thrombotic ischemic stroke or transient ischemic attack up to 60 days prior to the surgery. Every patient presented carotid stenosis over 70%. The plaque was removed during the surgery and the laboratory exams were immediately done. Evaluation of Chlamydia pneumoniae DNA was done using polymerase chain reaction (PCR). RESULTS: The PCR analyses of all 52 patients were negative for Chlamydia pneumoniae. CONCLUSION: These initial results do not show a relationship between Chlamydia pneumoniae and symptomatic carotid atherosclerotic plaque.OBJETIVO: Investigar a possível relação entre placa sintomática de carótidas e Chlamydia pneumoniae. INTRODUÇÃO: Vários estudos têm demonstrado uma possível relação entre Chlamydia pneumonia e aterosclerose carotídea, entretanto o papel definitivo da bactéria não é totalmente conhecido. Há muita especulação: poderia iniciar o processo aterosclerótico, agravá-lo ou desestabilizá-lo. MÉTODO: Estudo prospectivo com um total de 52 pacientes, endarterectomizados e previamente acometidos de acidente vascular cerebral isquêmico ou crise isquêmica transitória, em até 60 dias antes da cirurgia. Todos os pacientes apresentavam estenose carotídea superior a 70%. Os testes laboratoriais foram realizados imediatamente após a endarterectomia. A Chlamydia pneumoniae foi pesquisada através de exame de DNA com reação de polimerização em cadeia (PCR). RESULTADOS: O PCR dos 52 pacientes foram negativos para Chlamydia pneumoniae. CONCLUSÃO: Estes resultados iniciais não mostram relação entre Chlamydia pneumoniae e desestabilização de placa aterosclerótica das carótidas

    A Prospective Study Evaluating Patterns of Responses to the Caprini Score to Prevent Venous Thromboembolism After Interventional Treatment for Varicose Veins

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    Background Venous thromboembolism (VTE) is a critical complication of varicose vein treatments. The Caprini Score (CS) is an established tool to assess patients’ VTE risks. One disadvantage is the number of questions required, some of them referring to a low incidence of disease, even lower in patients seeking an elective procedure. These elements take time and may result in filling errors if the CS is not filled out by a properly trained health professional. Objective To establish a response pattern in CS, with emphasis on questions that usually have a negative answer and propose a simpler adaptative digital version without changing the original structure of the tool. Methods two hundred and twenty-seven patients in the pre-surgical treatment of varicose veins were enrolled prospectively and submitted to the CS evaluation. Results The pattern of dichotomous responses could be divided arbitrarily into four subgroups considering the percentage of positive responses: none (11 items), less than 3% (13 items), between 3% and 20% (5 items), and more than 20% (8 items). Of the 12 CS questions related to illnesses that occurred in the last month, ten had had no responses, and 2 were less than 3%. Conclusion There is a pattern in the CS responses of patients with an indication of surgical treatment of varicose veins. Many of the CS questions are not helpful in this scenario and may result in filling errors performed by untrained providers. An adaptative version of the CS might benefit varicose veins surgery VTE risk stratificatio
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