Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [106]-120).

Thesis (doctoral)--Tübingen, 1933.

Thesis (doctoral)--Tübingen, 1933.

No description available.

A contaminação por metais e agentes microbiológicos na água de hemodiálise pode ocasionar manifestações clínicas nos pacientes em tratamento, como anemia, dor óssea, picos hipertensivos, distúrbios neurológicos, episódios de hipotensão, náuseas e vômitos. Avaliar e garantir níveis mínimos de contaminação por metais e micro-organismos na água de hemodiálise pode, assim, aumentar a segurança do paciente. O objetivo deste estudo foi avaliar a relação entre a qualidade da água tratada para hemodiálise e as intercorrências clínicas apresentadas pelos pacientes. Foi utilizado um questionário para a coleta de informações referentes aos aspectos demográficos e hábitos de consumo, e um instrumento de registro mensal de intercorrências clínicas e parâmetros clínico-laboratoriais; tais informações foram obtidas por meio de entrevista e no prontuário do paciente, respectivamente. As dosagens de metais em sangue foram realizadas por EAA (Chama/ Forno de Grafite) no Setor de Metais do HCFMRP/USP, e em água por ICP/MS no Laboratório de Toxicologia e Saúde Ambiental da Universidade Rovira i Virgili, Espanha. A quantificação de bactérias heterotróficas foi realizada pelo Método \"Pour Plate\", a de Coliformes totais e E. coli por Tubos Múltiplos e a detecção de fungos filamentosos por Membrana Filtrante no Laboratório de Ecotoxicologia e Parasitologia Ambiental da EERP/USP. A quantificação de endotoxina foi realizada pela técnica cromogênica do lisado de Limulus Amebocyte, no Laboratório de Vacinas Gênicas da FMRP/USP. Para a análise dos dados foi aplicado o teste Wilcoxon- Mann Whitney bilateral ou Teste t bilateral no software R®, o teste de Kruskal-Wallis no software GraphPad Prism 6®, e ajustados modelos de regressão no software SAS/STAT®. Verificou-se que a concentração de Pb sérico entre os pacientes que exercem/exerciam atividades relacionadas à maior exposição a metais foi significativamente maior (p-valor = 0,0208) que aqueles que nunca realizaram tais atividades. A concentração média de Cu, Pb e Zn na água após filtração por osmose reversa (AFOR) foi inferior ao preconizado na RDC nº 154/2004 e RDC nº 11/2014 da ANVISA, somente o Al (15,35 ± 14,53 µg/L) apresentou concentração média superior a tais normativas. Não foi detectado presença, durante todo o período do estudo, de Cd, coliformes totais, E. coli e endotoxina na água AFOR. A contagem de bactérias heterotróficas foi significativamente maior (p-valor <0,0001) na água após a pré- filtração (APF) do que na água potável (AP) e na água AFOR. As concentrações de cloro total e nitrato foram significativamente maiores (p-valor <0,0001) na AP em relação à água APF e na água AFOR. A contagem de bactérias heterotróficas e a concentração de nitrato na água AFOR foi inferior ao preconizado nas normativas, o cloro total apresentou concentração média superior ao estabelecido na RDC nº 11/2014, mas dentro do limite preconizado pela RDC nº 154/2004. Foi verificado presença de fungos filamentosos em todos os pontos de coleta. Constatou-se que a diminuição da concentração de Cu e nitrato em água de hemodiálise foram significativos (p-valor = 0,001 e 0,0354, respectivamente) para explicar o aumento da concentração de hemoglobina em sangue. Embora a água utilizada no preparo do dialisato tenha apresentado excelente qualidade microbiológica e físico-química é importante o monitoramento contínuo para garantia dos parâmetros de qualidade e prevenção de intercorrências clínicas / The contamination by metals and microbiological agents in hemodialysis water can cause clinical manifestations in hemodialysis patients, such as anemia, bone pain, hypertensive peaks, neurological disturbances, hypotension episodes, nausea and vomiting. Evaluating and assuring minimum levels of contamination by metals and microorganisms in hemodialysis water can improve patient safety. The aim of the study was assess the relationship between the quality of treated water for hemodialysis and the clinical intercurrences presented by patients. A questionnaire was used to collect information about demographic characteristics and consumer habits, and an instrument was applied for monthly recording of clinical intercurrences and clinical laboratorial parameters. The data were obtained by interviews and from clinical records, respectively. Concentrations of metals in blood were determined by AAS (flame/graphite furnace) in the Metals Sector of HCFMRP/USP, and in water by ICP/MS in the Laboratory of Toxicology and Environmental Health of University Rovira i Virgili, Spain. The quantification of heterotrophic bacteria was performed by the pour plate method, the total coliforms and E. coli by multiple tubes, and filamentous fungi by the membrane filter at the Laboratory of Ecotoxicology and Environmental Parasitology of the EERP/USP. The quantification of endotoxin was performed by the chromogenic technique of Limulus Amebocyte lysate, at the Gene Vaccine Laboratory of the FMRP/USP. For data analysis, the bilateral Wilcoxon-Mann-Whitney or bilateral t-test was applied using the R® software, the Kruskal-Wallis test using GraphPad Prism 6®, and adjusted regression models with SAS/STAT®. The results showed that patients who reported having or having had job activities with high exposure to metals showed serum concentrations of Pb significantly higher (p-value = 0.0208) than patients without job exposure to metals. The mean concentrations of Cu, Pb and Zn in the water after reverse osmosis (ARO) were below the threshold limits set by RDC nº 154/2004 and RDC nº 11/2014 from the ANVISA; only Al (15.35 ± 14.53 µg/L) was present in average concentration higher than resolutions. The presence of Cd, total coliforms, E. coli and endotoxins in the water ARO during the study was not detected. The counting of heterotrophic bacteria was significantly higher (p-value <0.0001) in the water after the pre-filtration (APF) than the potable water (PW) and the wate ARO. The concentrations of total chlorine and nitrate were significantly higher (p-value <0.0001) in the PW than the water APF and the water ARO. The counting of heterotrophic bacteria and concentration of nitrate in the water ARO were below the reference limits, while the total chlorine was present in higher concentration than the established in RDC nº 11/2014 but lower than that in RDC nº 154/2004. Filamentous fungi were detected at all sampling points. The decrease in the levels of Cu and nitrate in hemodialysis water were significant (p value = 0.001 and 0.0354, respectively) to explaining the increase of hemoglobin concentration in the blood samples. Although the water used for dialysis showed excellen microbiological and physicochemical quality, it is important to monitor it regularly to assure the quality parameters and prevent clinical intercurrences

The research reported here investigated the use of a Baffle Reactor in order to study aspects of the biological sulfur cycle, where a floating sulfur biofilm formation occurs and where complex organic compounds provide electron donor sources. The development of a laboratory-scale Baffle Reactor model system satisfied the requirements for sulfate reducing bacterial biomass growth and sulfur biofilm formation. Since relatively little is known about the microbial ecology of floating sulfur biofilm systems, this study was undertaken to describe the sulfate reducing sludge population of the system together with its performance. A combination of culture- and molecular-based techniques were applied in this study in order to investigate the microbial ecology of the sulfate-reducing bacteria component of the system. These techniques enabled the identification and the analysis of the distribution of different sulfate reducing bacterial strains found within the sludge bioreactors. Strains isolated from the sludge were characterised based on culture appearance, gram staining and scanning electron microscopy morphology. Molecular methods based on the PCR-amplified 16S rRNA including denaturing gradient gel electrophoresis were employed in order to characterise sulfate-reducing bacteria within the reactors. Three novel Gram negative sulfate-reducing bacteria strains were isolated from the sludge population. Strains isolated were tentatively named Desulfomonas rhodensis, Desulfomonas makanaiensis, and Clostridium sulforhodensis. Results obtained from the Baffle Reactor showed that three dominant species were isolated from the DNA extracted from the whole bacterial population by peR. Three of these were similar to those mentioned above. The presence of these three novel unidentified species suggest that there are a range of other novel organisms involved in sulfate reduction processes.

Two biomass indicators (direct counts and ATP analysis) and two activity estimators (glucose uptake and dehydrogenase activity) were used to study the bacteria at 1 m water depth in Marlon Lake sediments. Direct count-biomass estimates for bacteria averaged 0.6l gC/m², were high in summer, declined rapidly in fall, then increased during the winter. Microorganisms less than approximately 30 μm diameter had a mean biomass of 1.28 gC/m² as measured by ATP analysis. Seasonal variations in this figure paralleled changes in the algal population, although algal contributions to the microbial biomass were less than 50 per cent. ATP analysis was also used to estimate the biomass of the sediment community, excluding animals greater than approximately 5 mm in length. The mean community biomass was 4.69 gC/m². Comparison of ATP data with enumeration data obtained by others, suggests that ATP is a good biomass indicator, except when cellular ATP levels are changed in reaction to biotic or abiotic environmental factors. It is proposed that, in situations such as intense grazing or rapid Increases or decreases in temperature, ATP measurements reflect not only biomass but also activity. At such times ATP-biomass data may Indicate biomass potential, or the capacity of the population to maintain its biomass under abnormally high rates of loss. Dehydrogenase activity, or respiratory potential, of the sediment bacteria was assayed using trlphenyl tetrazolium chloride. The estimate for annual rate of carbon loss as CO2 from the bacterial population (19.3 g C/m²•year), was almost identical to previously reported data obtained by measuring oxygen consumption in normal and antibiotic-treated sediment cores. Uptake of ¹⁴C-glucose was determined in mixed, diluted sediments. The maximum uptake rate (9.6 g C/m².year), natural uptake rate (5.3 S C/m².year) and the natural turnover time (0.31 h) were similar to previous data for these sediments. This suggests that, at least in terms of function, the bacterial population is quite stable from year to year. Biomass and activity of the Marion Lake sediment bacteria were found to be in phase in late spring through early fall, but activity remained low in winter despite Increases in the microbial biomass, and increased much more rapidly than biomass in early spring. The dynamics of the bacterial population are discussed in terms of these relationships. The size of the algal and bacterial populations and organic matter reservoirs, and the flux rates for carbon between these compartments are summarized. / Science, Faculty of / Zoology, Department of / Graduate

Access to a safe drinking water supply is a critical issue in a number of places across the globe. Conventional water quality monitoring technologies are slow, often taking at least two days to produce results. In recent years, there has been extensive research into emerging technologies that provide real-time results; however, there is no technology which detects all classes of biological contaminants. Biological contaminants are 5 particularly difficult to detect and quantify due to low concentrations typically present. It is not feasible to identify all biological contaminants present in a water supply; therefore, it is necessary to determine which are of highest concern based factors such as health significance, infectivity, and prevalence. The intent of this research is to evaluate microbiological detection methods and technologies based on their applicability for continuous real-time detection. This research will complement current research on biological water quality monitoring technologies for use in developing regions or in the event of an emergency and will provide suggestions for future research efforts.

The comprehensive environmental dynamics of the heterocyclic Benzimidazole fungicides, Benomyl and Thiabendazole was investigated. This included examining their fate and distribution in the terrestrial and aquatic phases of a laboratory microcosm comprised of silty clay loam soil and plants. The soil component constituted a major relocation site, with approximately 45 and 75% of initial Benomyl (recovered as MBC) and Thiabendazole concentrations being recovered from the soil component of the microcosm, respectively, while 53 and 27% translocated into corn plants. The adsorption mechanism/s of these fungicides onto soil components were investigated using silty clay loam, silty loam and sandy soils as well as Ca-bentonite. These studies indicated that both fungicides were adsorbed to the highest degree on silty clay loam, followed by silty loam and sandy soils. Their adsorption on Ca-bentonite was found to be a function of the pH of the suspension, suggesting that in the presence of increasing ll *activity on the clay surfaces, Benomyl and Thiabendazole become protonated to form positively charged molecules. These may then react with the clay surfaces forming Fungicide-clay complexes. The effect of different CaCl, concentrations on the adsorption process demonstrated that an increase in the salt concentration, at a constant pH resulted in a decrease in the amounts of adsorbed fungicide. The transport of the fungicides (adsorbed onto soil particles) as a consequence of scdiment runoff into aquatic systems was also estimated. Results of the simulation of overland sediment runoff from sections of the Chowan river basin into the Meherrin river following a rainstorm, indicate that significant quantities of Benomyl and Thiabendazole could be transported into aquatic systems. Adsorption studies also indicated that the adsorption process is reversible. Thus, any significant increases in the pH of receiving bodies of water could result in the release of Benomyl and Thiabendazole from sediment causing a contamination of the aquatic system. / Master of Science

No description available.