Thesis (M.S.)--University of Michigan, 1964.

Thesis (M.Sc. (Zoology & Entomology)) - Rhodes University, 2008.

Thesis (M.S.)--University of Michigan, 1970.

Thesis (M.S.)--University of Michigan, 1964.

Orientador: Reinaldo Wilson Vieira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-16T22:33:56Z (GMT). No. of bitstreams: 1 Oliveira_FernandoJosede_D.pdf: 842706 bytes, checksum: c55e580b4ebd9d2c192bd493430bf790 (MD5) Previous issue date: 2010 / Resumo: Objetivo: Processos inflamatórios e infecciosos mediados por bactérias em sítios distantes têm sido descritos como fator de risco à doença coronariana isquêmica aguda (DCIA). Métodos: Cento e oitenta e um pacientes com DCIA, com e sem periodontites crônicas, foram incluídos neste estudo. Os pacientes foram admitidos no HC da UNICAMP e estratificados em três grupos: grupo 1- pacientes com periodontite crônica grave (31 homens e 19 mulheres; média de idade 55,1 ± 11,29 anos); grupo 2- pacientes com periodontite crônica leve (40 homens e 28 mulheres; média de idade 54,8 ± 10,37 anos); grupo 3- pacientes desdentados (43 homens e 20 mulheres; média de idade 67,5 ± 8,55 anos). Amostras sanguíneas foram coletadas para mensurar os perfis lipídico, hematológico e glicêmico. Além disso, biópsias de 17 artérias coronárias com aterosclerose e igual número de artérias torácicas interna sem degeneração aterosclerótica no grupo 1 foram investigadas. Para análise estatística utilizou-se a análise de variância (ANOVA) e o teste de Scheffé para comparações múltiplas. Resultados: Triglicérides e LDL estavam elevados no grupo 1 em relação ao grupo 2. O HDL apresentou-se reduzido em 20% dos pacientes do grupo 1, e em 8% nos desdentados. A glicemia estava elevada no grupo 1. DNA de bactérias periodontais foram detectados em 58,8% das artérias coronárias. Conclusões: Pacientes com DCIA e periodontite crônica grave podem apresentar perfil lipídico alterado, como também microorganismos associados com as periodontites crônicas graves podem permear dentro de vasos coronarianos / Abstract: Objective: Infectious and inflammatory processes mediated by bacteria in distant sites have been described as a risk factor for acute ischemic heart disease (AIHD). Methods: One hundred one patients with AIHD with and without chronic periodontitis (CP) were included in this study. Patients were admitted to the HC-UNICAMP and stratified into three groups: in group 1, we selected patients with severe chronic periodontitis (31 men and 19 women, mean age 55,1 ± 11,29 years old); the group 2 with mild chronic periodontitis (40 men and 28 women, mean age 54,8 ± 10,37 years old) and group 3 represented by the toothless (43 men and 20 women, mean age 67,5 ± 8,55 years old). Blood samples were collected to measure the lipid profiles, hematological and blood glucose levels. In addition, biopsies of seventeen coronary arteries with atherosclerosis and an equal number of internal thoracic artery without atherosclerotic degeneration in group 1 were investigated. Statistical analysis by analysis of variance (ANOVA) and Scheffé test for multiple comparisons was performed. Results: Triglyceride and LDL levels were elevated in group 1 than in group 2. HDL were reduced by 20% in group 1 and remained reduced by 8% in toothless. Blood glucose was higher in group 1. DNA of periodontal bacteria was detected in 58,8% of the coronary arteries / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências

Recent studies have characterized coastal estuarine systems as important components of the global carbon cycle. This study investigated carbon cycling through the microbial loop of Florida Bay by use of bacterial growth efficiency calculations. Bacterial production, bacterial respiration, and other environmental parameters were measured at three sites located along a historic phosphorus-limitation gradient in Florida Bay and compared to a relatively nutrient enriched site in Biscayne Bay. A new method for measuring bacterial respiration in oligotrophic waters involving tracing respiration of 13C-glucose was developed. The results of the study indicate that 13C tracer assays may provide a better means of measuring bacterial respiration in low nutrient environments than traditional dissolved oxygen consumption-based methods due to strong correlations between incubation length and δ13C values. Results also suggest that overall bacterial growth efficiency may be lower at the most nutrient limited sites.

Temperature and relative humidity of produce throughout the cold chain can greatly affect the quality and safety of the food product. Different packaging systems or containers can provide better cooling environments for food products that could decrease temperature abuse and ultimately safety risks. In this study we compiled temperature and relative humidity profiles of broccoli packed in different shipping containers throughout the produce supply chain. The shipping containers looked at were the wax corrugated box, reusable plastic containers (RPC), and Eco Pack Green Box with and without a lid. Large differences were seen in the temperature profiles of each package during the first 15 hours of the cold chain with the wax-corrugated boxes showing the slowest rate of cooling. Growth rates of Salmonella sp. and Listeria monocytogeneson broccoli at different temperatures were also determined. Salmonella sp.showed a greater ability to grow on inoculated broccoli than Listeria monocytogenesduring higher temperatures such as 20° C and 37° C. Temperature profiles along with microbial counts from produce lots have been previously recorded; this is the first study to record temperature and relative humidity profiles in conjunction with bacterial growth data of lab inoculated produce.

Bioremediation of seleniferous water is gaining more momentum, especially when it comes to bacterial reduction of the selenium oxyanions. More and more bacterial strains that are able to reduce selenium are being isolated. These bacteria need to be studied further to determine whether they are suited for industrial application. In this study, the reduction of Se(VI) to Se(0) by Pseudomonas stutzeri NT-I was examined using batch experiments with the bacteria suspended in MSM. For the determination of the optimum conditions for the growth of the bacteria, the linearized rate during the exponential phase for different conditions were compared. A pH of 7, temperature of 37 ⁰C, salinity of 20 g.L-1 NaCl and initial concentration of 5 mM selenate were found to be the best at promoting growth. To determine the optimum conditions for the reduction of selenium, the amount of Se(0) recovered from the plug after 16 hours of incubation was measured. A pH of 8, temperature of 37 ⁰C and salinity of 5 g.L-1 resulted in the most Se(0) recovered. The kinetics of the reduction of Se(VI) to Se(0) was found to follow the adapted Monod equation. An increase in the initial Se(VI) concentration positively affected the reduction rate indicating that substrate saturation had not yet been reached. One kmax could be fitted to each of the two reactions but not one Ks. It was found that Ks decreased with increasing initial selenate concentration. Visually it can be deduced that inhibition starts playing a role in the reduction of selenate at a concentration of 4 mM. Pseudomonas stutzeri NT-I is an exemplary selenium reducing agent and deserves more attention, not only for industrial application but also in the research world, for further understanding of the complex mechanism behind metal reduction in bacteria. / Dissertation (MEng)--University of Pretoria, 2017. / Chemical Engineering / MEng / Unrestricted

Utilization of cyanide as a nutritional nitrogen source in P. fluorescens NCIMB 11764 was shown to involve a novel metabolic mechanism involving nonenzymatic neutralization outside of cells prior to further enzymatic oxidation within. Several cyanide degrading enzymes were produced by NCIMB 11764 in response to growth or exposure to cyanide, but only one of these cyanide, oxygenase (CNO), was shown to be physiologically required for assimilation of cyanide as a growth substrate.

Heterotrophic bacterioplankton dynamics have seldom been assessed in the Red Sea, an exceptionally warm oligotrophic basin, which could be used as a model for the future ocean. To understand the function of heterotrophic bacteria in biogeochemical cycles and the flows of matter and energy to higher trophic levels, it is peremptory to understand how bacterial growth is controlled. Bottom-up (resources availability), top-down (mortality by predators and viruses) and temperature are the main hypotheses of control of bacterial activity and stocks. This dissertation aims to assess the spatial-temporal variability of heterotrophic bacteria and their interactions with diverse sources of dissolved organic matter (DOM) through the observed effects on bacterial growth rates and productivity in coastal environments of the central Red Sea. To that end we conducted a total of 66 shortterm incubations (4-6 days) concurrently with the whole microbial community and predator-free (by filtration) in various shallow ecosystems characterized by different dominant sources of DOM. Frequent sampling combined flow cytometry and biogeochemical analysis allowed us to measure bacterial standing stocks, including the carrying capacity (maximum abundances), growth rates, characterize DOM concentrations and lability, assess bacterial DOM consumption rates and biomass production and ultimately quantify bacterial growth efficiencies. Our findings suggest that although bacteria seemed to thrive in nutrient-sufficient waters, the central coastal Red Sea is characterized by unusually low bacterial standing stocks (4.05 ± 0.31 x105 cells ml-1), probably controlled by protistan grazing. At the same time, bacterioplankton showed high potential to grow (0.35-1.75 d-1, reaching 4.16 d-1 when dilution and pre-filtration were performed). Even though the highest specific growth rates were observed during the warmer periods, we did not find any consistent relationship with temperature. While temperature seemed not to constrain bacterial specific growth rates, we observed a tight link between bacterial growth and resource availability in terms of both quantity and quality. Overall, by surveying one of the warmest marine regions on Earth, this dissertation provides detailed insights into heterotrophic bacterioplankton dynamics and how bottomup, top-down and temperature regulate them in tropical waters, a vast geographical extension of the world oceans that had remained strongly undersampled to date.