Orientador: Claudio Alexandre Gobatto / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Aplicadas / Made available in DSpace on 2018-08-24T02:33:33Z (GMT). No. of bitstreams: 1 Forte_LucasDantasMaia_M.pdf: 1545024 bytes, checksum: fa9618e31fd5a31914dfc5ebb2b0e5b6 (MD5) Previous issue date: 2013 / Resumo: Resumo: Desde sua concepção, os fenômenos dos limiares anaeróbios ganharam grande atenção das ciências do esporte e da saúde como uma importante ferramenta na avaliação e prescrição de treinamento aeróbio. Diversos protocolos foram desenvolvidos para se determinar os limiares 1 e 2. Contudo, tais protocolos são compostos por esforços de alta intensidade e/ou longa duração. Em 1986, um protocolo composto por duplos esforços não-exaustivos (DENE) que possivelmente determinaria uma das zonas de transição metabólica (limiar 1 ou 2) foi proposto, porém pouco estudado. Assim, os objetivos da presente pesquisa foram de: 1) Determinar as intensidades do DENE (iDENE) por meio de análises de lactato sanguíneo, consumo de oxigênio (VO2) e frequência cardíaca (FC) (DENELAC,VO2,FC); 2) Comparar os valores de velocidade preditos pelo DENELAC,VO2,FC com as encontradas pela máxima fase estável de lactato (MFEL), limiar ventilatório 1 e 2 (LV1 e LV2); 3) Correlacionar as intensidades preditas pelos protocolos estudados; 4) Verificar a reprodutibilidade do DENELAC,VO2,FC por meio de procedimento de teste e reteste. Para tanto, 19 voluntários do sexo masculino, saudáveis e moderadamente ativos realizaram quatro testes para a determinação dos limiares dentro de duas a três semanas. Após as medidas antropométricas, os voluntários assinaram o termo de compromisso livre e esclarecido e preencheram o international physical activity questionnaire (IPAQ) para sua classificação mínima como "moderadamente ativos". Em seguida, os voluntários realizaram o protocolo em rampa individualizado para a determinação do LV1, LV2 e consumo máximo de oxigênio (VO2max). Os limiares foram determinados por análise visual dos equivalentes ventilatórios 1 e 2 (VE/VO2 e VE/VCO2) e o VO2max foi obtido pelo maior valor de consumo de oxigênio durante o teste. A MFEL foi determinada por meio de testes de cargas retangulares com duração de 30min em diferentes dias, sendo considerada como a maior intensidade na qual se observou estabilização do lactato sanguíneo nos últimos 20min de teste. O teste de DENE foi composto por quatro aplicações de duplos esforços, cada um realizado sob diferentes intensidades. A intensidade do DENE (iDENE) foi determinada pelo intercepto-y de uma regressão linear entre a diferença das variáveis fisiológicas (lactato, VO2 e FC) do primeiro e do segundo esforço com as velocidades de cada duplo esforço. Os valores em média ± DP das intensidades de LV1, LV2, MFEL foram respectivamente: 10,22 ± 0,97, 12,59 ± 0,94 e 12,13 ± 1,21. Os valores das iDENE determinados pelo lactato, VO2 e FC foram de: 10,54 ± 1,45, 10,71 ± 1,30, 9,79 ± 1,96 respectivamente. O ANOVA apontou diferenças estatísticas entre o iDENELAC,VO2,FC e LV1 comparados à MFEL e LV2 (p < 0,05). Não foi identificado diferenças significativas entre a iDENELAC,VO2,FC e o LV1 (p > 0,05). O DENE predito pelas três variáveis fisiológicas (lactato VO2 e FC) foi estatisticamente correlacionado com o LV1 e a MFEL. A iDENELAC,VO2,FC apresentaram bons índices de correlação intraclasse (0,87, 0,49 e 0,66 respectivamente) e de coeficiente de variação (5,1, 9,0 e 11,7 respectivamente). Além disso, os valores das diferenças das velocidades do teste e reteste do DENE estiveram dentro do limite de concordância nos plots de Bland & Altman. Estes resultados sugerem que o protocolo de DENE realizado por meio das três variáveis fisiológicas abordadas (lactato, VO2 e FC), é um procedimento de boa reprodutibilidade e capaz de estimar o primeiro limiar ventilatório. / Abstract: Since its conception, the phenomena of anaerobic threshold gained wide attention from sports and health sciences as an important tool on assessment and prescription of aerobic training. Several protocols have been developed to determine the thresholds 1 and 2. However, such protocols are composed of high intensity and/or long term efforts. In 1986, a protocol consisting of non-exhaustive double efforts (DENE) that possibly determine one of the metabolic transition zones (threshold 1 or 2) was proposed, but little studied. Thus, the objectives of this research were to: 1) determine the DENE intensities (iDENE) through analysis of blood lactate, oxygen uptake (VO2) and heart rate (FC) (DENELAC, VO2, HR), 2) Compare the values speed predicted by DENELAC,VO2,FC with those found by the maximum lactate steady state (MFEL), ventilatory threshold 1 and 2 (LV1 and LV2), 3) correlate the intensities predicted by the protocols studied, 4) Verify the reproducibility of DENELAC,VO2,FC through test-retest procedure. To this end, 19 male subjects, healthy and moderately active realized four tests to determine the thresholds within two to three weeks. After anthropometric measurements, the volunteers signed an informed consent form and completed the International Physical Activity Questionnaire (IPAQ) to their minimum rating as "moderately active". Then, the volunteers performed an individualized ramp protocol for the determination of LV1, LV2 and maximal oxygen uptake (VO2max). The thresholds were determined by visual analysis of ventilatory equivalents 1 and 2 (VE/VO2 and VE/VCO2) and VO2max was obtained at the higher oxygen consumption during the test. The MFEL was determined by testing with constant loads lasting 30 minutes on different days. It was taken as the highest intensity where the stabilization of lactate in the last 20 minutes of the test was observed. The test DENE was composed by four double efforts applications each performed at different intensities. The iDENE was determined by the intercept-y of a linear regression between the difference of physiological variables (lactate, VO2 and FC) of the first and second efforts with the speeds of each double effort. The mean ± SD values of intensities of LV1, LV2 and MFEL were respectively: 10.22 ± 0.97, 12.59 ± 0.94 and 12.13 ± 1.21. The values of iDENE determined by lactate, VO2 and FC were: 10.54 ± 1.45, 10.71 ± 1.30, 9.79 ± 1.96 respectively. The ANOVA showed significant differences between the iDENELAC,VO2,FC and LV1 compared to LV2 and MFEL (p < 0.05). No significant difference was identified between the iDENELAC,VO2,FC and LV1 (p > 0.05). The DENE predicted by the three physiological variables (lactate VO2 and FC) were statistically correlated with the LV1 and MFEL. The iDENELAC,VO2,FC showed good intraclass correlation coefficients (0.87, 0.49 and 0.66 respectively) and coefficient of variation (5.1, 9.0 and 11.7 respectively). Moreover, the values of the differences of velocities of DENE test and retest were within the limits of agreement in the Bland & Altman plots. These results suggest that the protocol DENE performed by means of the three physiological addressed (lactate, VO2 and FC) is a reliable procedure of good reproducibility and capable of estimating the first ventilatory threshold. / Mestrado / Biodinâmica do Movimento Humano e Esporte / Mestre em Ciências da Nutrição e do Esporte e Metabolismo

Introduction: R factor mediated transfer of antibiotic resistance between Enterobacteriaceae has been reported to occur in the mammalian gastrointestinal tract (Farrar et al, 1972; Guinée, 1970; Kasuya, 1964; Reed et al, 1969; Wiedemann et al, 1970). In vivo conjugal transfer of genetic material has also been demonstrated with F¹, F⁺ and Hfr Escherichia coli strains (Jones & Curtiss, 1970). The environment in the lower gastrointestinal tract, where bacteria are abundant, is mainly anaerobic. This is demonstrated by the dominance of obligately anaerobic bacteria such as Bacteroides species (Finegold, 1969; Moore et al, 1969) and direct studies of intestinal gas composition (Askevold, 1956). However, most laboratory investigations of the incidence of R factors and their transfer frequencies have been performed under aerobic conditions using faecal facultative strains. The only investigation of resistance transfer under anaerobic conditions in vitro is that of Mitsuhashi (1965), who reported complete inhibition of transfer of an R factor from a Shigella flexneri donor to an Escherichia coli recipient. In addition, Fisher (1957) reported restriction of chromosomal transfer by an E. coli Hfr strain under anaerobic conditions in various media. On the basis of these results, it could be questioned whether in vivo R factor transfer is in fact possible (Chabbert et al, 1969). The contradictory situation prompted a reexamination of conjugation in facultative strains under anaerobic conditions. Both Fisher (1957) and Mitsuhashi (1965) obtained anaerobic conditions by evacuation. In this investigation, both mating and selection of recombinants were performed under stringent anaerobic conditions using methods developed for the isolation of obligate anaerobes (Hungate, 1969) to obtain a degree of anaerobiosis similar to that found in vivo.

Class of 2013 Abstract / Specific Aims: Metronidazole and clindamycin can be prescribed for anaerobic infections; however, patients are periodically prescribed a second agent with duplicate anaerobic coverage. The purpose of this project was to evaluate the frequency, appropriateness, and potential consequences of combination therapy against anaerobic organisms in patients prescribed metronidazole or clindamycin. Methods: In this IRB approved project, adult patients who were prescribed either intravenous metronidazole or intravenous clindamycin with or without another agent with anaerobic coverage for at least 48 hours at an academic medical center between May 2010 and April 2012 were evaluated. Subjects were excluded if documented Clostridium difficile associated diarrhea within 14 days prior to intravenous metronidazole, if use of oral vancomycin within 14 days prior to intravenous metronidazole, or if presence of diarrhea with more than six unformed stools 48 hours prior to intravenous metronidazole. Data collected includes demographic information, site of infection, surgical interventions, antibiotic therapy prescribed, therapy outcomes, and reported adverse events. The odds ratio for combination anti-anaerobic therapy was calculated for metronidazole and clindamycin. The appropriateness of combination anaerobic coverage therapy was evaluated based on expert opinion and guideline statements. The frequency of potential complications such as adverse drug events, Clostridium difficile infection, other diarrheal illness and superinfections associated with enteric organisms within 30 days after starting anaerobic therapy will be reported Main Results: In Progress Conclusion: To be determined

No description available.

No description available.

This study concerns a determination as to whether anaerobic organisms are involved in pulmonary diseases, particularly those of the chronic type.

Mercury (Hg) is a global pollutant and potent neurotoxin that is detrimental to the environment and human health. (MeHg). All forms of Hg are toxic, but methylmercury (MeHg) can biomagnify through food webs and become concentrated in food staples such as fish and rice, creating an exposure risk to people. The conversion of Hg to MeHg is mediated by anaerobic microbes, particularly sulfate and iron-reducing bacteria and methanogenic archaea. However, Hg methylation is an intracellular process, and MeHg production is dependent on the bioavailability of inorganic Hg to these microbes. One outstanding knowledge gap in understanding Hg methylation is the nature of bioavailability of inorganic divalent Hg (HgII). Much research has gone into developing a framework describing how microbes take up Hg for methylation. Still, the framework describing Hg bioavailability processes is not fully developed. The overall objective of my thesis is to address these mechanisms governing HgII bioavailability to anaerobic microbes. HgII bioavailability is determined by its speciation; these are all the different forms and compounds of HgII. To address the bioavailability of various HgII species, I used microbial Hg-biosensors. Hg-biosensors are bacterial cells that emit a quantifiable signal when HgII enters them and let me observe HgII bioavailability in real-time. The biosensors I developed are the first Hg-biosensors that function without oxygen and let me explore HgII species and their bioavailability under conditions conducive to methylation. HgII speciation is spatially and temporally dynamic moving from oxic to anoxic conditions and under various biogeochemical controls. I follow HgII speciation and bioavailability in my thesis as it transgresses through these conditions. Understanding HgII bioavailability to complex microbial communities across redox gradients and through dynamic ligand interactions is a missing key component to understanding and predicting MeHg formation. My results show how altering HgII speciation can identify novel bioavailability pathways or make it completely inaccessible. My results highlight how microbes can control HgII bioavailability and the importance of microbial community structure on metal acquisition. First, I resolve pathways for charged inorganic HgII species through the cell membrane and demonstrate novel pathways for previously unconsidered charged species. Using dissolved organic matter (DOM) originating from various algal species, I show how algae can uniquely control HgII bioavailability to other organisms. I demonstrate how DOM has emergent properties that can control HgII bioavailability. Next, I investigated the compounds microbes use to scavenge metals such as iron and copper. I reveal how they could inadvertently interact with HgII and form new bioavailability pathways. Lastly, I demonstrate how the diffusion of biogenic hydrogen sulfide from an isolated system can make an otherwise non-bioavailable HgII species rapidly available for microbial uptake. Overall, my thesis expands the framework describing HgII bioavailability to microbes and potential drivers of Hg methylation in the environment.

Sustainable and environmentally friendly waste-to-energy conversion technologies, such as anaerobic digestion (AD) and gasification, have received significant attention in recent energy research. These technologies have proven their ability to reduce reliance on fossil fuels and greenhouse gas emissions by converting organic waste into products and fuels with market value, such as biomass, biogas, and synthetic gas. Since the syngas produced by biomass gasification contains highly toxic CO and flammable H₂, converting syngas into renewable natural gas has recently gained a lot of interest. By coupling AD with syngas, microbial consortium in the AD reactor converts the syngas into methane through a process known as biomethanation. Feeding syngas into the AD reactor is a method that not only can enhance methane production by conversion of CO₂ to CH₄ during the AD process but also converts syngas into methane as pure energy. This study aims to assess and compare the effect of different syngas compositions on methane production and optimize the SB process by identifying the best syngas composition and gas-biomass ratio under mesophilic temperature conditions. The study was conducted using batch and semi-continuous reactors in a lab-scale setting. The results of this study can contribute to the development of more efficient and sustainable methods for SB. In phase I of this study, syngas biomethanation under different syngas compositions was conducted under three different gas-biomass ratios (0.5, 1 and 1.5) in bench-scale experiments to study the impact on CO and H₂ partial pressure and CO toxicity on operation parameters (e.g., pH and VFA) and syngas conversion efficiency. The results showed that the optimum syngas composition with the highest amount of CH₄ is H₂-rich syngas (CO₂:CO; H₂ 1:1:7) and syngas with stoichiometric ratios between H₂ and CO/CO₂ (CO:H₂ 1:3; CO₂:H₂ 1:4) because of the sufficient available amount of hydrogen in the headspace. Methane content in the produced biogas reached 80.0%, 63.6% and 57.7%, respectively, compared to the control sample with 30.2% methane in the headspace. In phase II, the optimum syngas compositions were selected for experimenting with semi-continuous mode to 1) investigate the effect of injecting syngas in several stages in increasing syngas conversion efficiency, 2) adapt microorganisms to hydrogen and enhance biohydrogen production, and 3) test higher stoichiometric ratio between H₂ and CO/CO₂ to enhance syngas biomethanation efficiency. The data indicated higher methane content and syngas conversion in a semi-continuous mode. The biogas had methane concentration of 82.3, 76.9, 73.8, 84.9 and 81.7% in samples CO₂:CO: H₂ (1:1:7), CO:H₂ (1:3), CO₂:H₂ (1:4), CO: H₂ (1:4) and CO₂:H₂ (1:5). By injecting gas into the biomass in several stages, methane levels in the produced biogas in each stage increased, demonstrating the adaptation of microorganisms to the injected hydrogen and carbon-sourced gases. A higher stoichiometric ratio of H₂ to CO/CO₂ promoted the growth and activity of methanogens, leading to increased methane production.

<p> A study was made to determine the elimination rate of soluble organic and inorganic compounds during anaerobic storage. Using aerobic storage as a comparison, some insight could then be gained into the metabolic activities of a mixed culture.</p> <p> The rate of oxygen utilization following anaerobic storage appeared to be dependent on the level of aeration within the reactor prior to storage. There was no liberation of carbon to account for the increased oxygen uptake following storage. Although there was a slight decrease in the solids level, it was independent of the type of storage.</p> <p> The nitrate ion appeared to act as a hydrogen acceptor during anaerobic storage and, upon reaeration, the nitrate level tended to level off. There was a production of ammonia during both aerobic and anaerobic storage indicating a deamination of cellular material (loss of solids).</p> / Thesis / Master of Engineering (MEngr)

The purpose was to directly assess the relative contributions of the anaerobic energy releasing pathways to ATP provision during very brief (2-14s) maximal isometric contractions in human skeletal muscle, and to examine the recovery processes following such exercise. Eleven males performed unilateral sustained maximal isometric contractions of the knee-extensor muscles. Ten needle biopsy samples [2 pre-exercise (PreEx), 4 exercise (Ex), and 4 recovery (Rec) samples] were obtained from each subject over 3 separate testing sessions. Circulation was occluded at the upper thigh prior to all biopsies. Ex samples were taken immediately following 2-14s of maximal voluntary contraction. Contraction times were randomly pre-determined such that 6 biopsies were obtained following each of 2, 4, 6, 8, 10, 12, and 14s of contraction. Rec samples were collected 10, 20, 30, 40, 60, 120, and 180s following 14s maximum contractions. Significant changes occurred for both phosphocreatine (PCr) and lactate concentration within the initial 2s (n=7, p≤0.05) of contraction. In 14s, PCr concentration decreased to 53.3% of the PreEx value at a rate of 2. 53±0 .18 mmol· kg⁻¹dm · s⁻¹, while muscle lactate increased to approximately 8 times the initial value, at a steady rate of 1. 52±0 .10 mmol ·kg⁻¹ s⁻¹. Following contraction, PCr returned to the PreEx value within 60s of recovery (n=4, p>O. OS) , but muscle lactate concentration was still significantly elevated above resting after 180s of recovery (n=4, ≤0.05). Total ATP production over 14s was 69.03±4.47 ⁻¹dm, with an average turnover rate of 4.93±0.32 mmol·kg⁻¹dm·s⁻¹. The initial ATP turnover rate was 7. 26±1. 94 mmol· kg⁻¹ dm· s⁻¹ with 67% of the ATP being derived from PCr degradation and 33% from glycogenolysis. As contraction continued, however, there was an almost equal contribution to ATP provision from the 2 anaerobic energy delivery pathways, and (with the exception of the first 2 seconds) the proportion changed very little over time. This study was supported by the Natural Sciences and Engineering Research Council of Canada. / Thesis / Master of Science (MSc)