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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Left ventricular morphology : the impact of menstrual cycle phase, oral contraceptive use, body size, body composition and athletic training

George, Keith Phillip January 1998 (has links)
No description available.
2

SCALING OF METABOLIC ENZYMES: TRANSCRIPTIONAL BASIS OF INTERSPECIES VARIATION IN MITOCHONDRIAL CONTENT

GENGE, CHRISTINE E 15 June 2010 (has links)
Mitochondrial content, an important determinant of muscle metabolic capacity, changes in individuals during development, and in response to physiological and environmental challenges. This phenotypic plasticity is attributed to the coactivator PPARγ coactivator-1α (PGC-1α) but it remains unclear if this transcriptional regulator accounts for evolutionary variation in mitochondrial content. In an attempt to explain why some species have higher muscle mitochondrial enzyme levels than other species, I examined if the transcriptional mechanisms that control mitochondrial content of a tissue in an individual are also responsible for differences between species. If PGC-1α creates differences between the mitochondrial content of species based on variation in promoter binding motifs, then cis-factor evolution may be the guiding force in scaling trends. In this thesis I explored the basis of size-dependent patterns by looking at layers of regulation, from catalytic activities to promoter evolution and regulation. A representative family, Rodentia, was used to collect muscle samples from a size range of approximately 20g up to 17 kg. As expected, in rodent lower limb muscles, mitochondrial and glycolytic enzyme activity exhibited reciprocal scaling patterns, though the scope differed between muscles. Very little of the variation was accounted for when the activity was related to DNA content. However, when COX activities were expressed relative to DNA, the scaling patterns were similar among the 3 muscles. To determine if interspecies differences were linked to transcriptional regulation, ~800bp of the PGC-1α promoter from 56 terrestrial mammals (5g-5000kg) was examined. The basal placental mammalian promoter possesses putative elements for Sp1, HNF3, myogenic factors and metabolic effectors, which have been retained in mammals with little change in order or spacing. To investigate the ability of these promoters to control PGC-1α expression, rodent promoters were cloned into luciferase reporter gene constructs and transfected into a common mouse myoblast background (Sol8 cells). Unlike mitochondrial content, promoter activity did not vary with body size across the rodent family. Likewise, PGC-1α transcript levels did not vary in rodent muscles in a way that would explain differences in COX activity. This suggests that though PGC-1α may be crucial for within species variation, transcriptional regulation of PGC-1α is not responsible for interspecies variation in mitochondrial content. / Thesis (Master, Biology) -- Queen's University, 2010-06-09 10:50:02.133
3

Evaluation of the Allometric Exponents in Prediction of Human Drug Clearance

Zhang, Da 01 January 2014 (has links)
Background. Allometric scaling (AS) is widely used in predicting human clearance (CL) based on animal data. Substantial prediction errors have been commonly observed and various modifications to AS have not provided a broad reliable improvement. In this study, an extensive data set was assembled including animal and human systemic CL and physiochemical properties. The allometric exponents were calculated based on multiple species AS and single-species AS methods. The correlations between the allometic exponents and physiochemical properties were evaluated in an attempt to find covariates that may explain the inter-compound variability in the allometric exponents. Lastly, the statistical approaches in analyzing the allometric function were evaluated with the collected data. Methods. 1- A nonlinear mixed effect modeling (MEM) approach was performed to investigate the central tendency and distribution of AS exponents as well as to identify whether there are any correlations between the allometric exponent, and coefficient, with the physicochemical and drug metabolism and pharmacokinetics (DMPK) properties of the compounds. 2- Single-species AS was performed to estimate the single-species AS exponent distributions and their corresponding central tendencies. The correlation between the estimated single-species AS exponents and the physicochemical and DMPK properties of the compounds were also examined. 3- The methodologies of log-log transformation followed by linear regression (LL-LR) and direct nonlinear regression methods (NLS) with different weighting schemes on the AS power function were investigated. The central tendency and distribution of the allometric exponents were evaluated and compared across methods. Furthermore, the human CL prediction performance was evaluated among methods. Results. The estimated central tendency and distribution of AS exponents from the nonlinear MEM as well as the single-species AS approaches were consistent with literature reports. There were no significant correlations identified between the estimated AS exponents and the physicochemical or DMPK properties. The methods of LL-LR and the NLS with 1/w2 weighting (variance weighted by CL2 during the variance minimization process) results in the most similar allometric exponent with central tendency around 0.668 and provided the best human CL prediction among methods investigated. Conclusion. The knowledge gained in this work by extensive modeling and simulations contributed to a better understanding of the variability in AS exponents and better practice in performing AS in human CL prediction
4

Testes de corrida/caminhada de 6 e 9 minutos: validação e determinantes metabólicos em crianças e adolescentes

Lorenzi, Thiago Del Corona January 2006 (has links)
O entendimento da aptidão cardiorrespiratória em crianças e jovens é hoje uma estratégia fundamental de controle da saúde em geral. No entanto, avaliar a aptidão cardiorrespiratória, de forma direta, demanda um custo financeiro alto, pessoal especializado e um tempo excessivo. Nesta perspectiva, inúmeros estudos vêm propondo testes que avaliem, de forma indireta, a aptidão cardiorrespiratória de crianças e jovens. Assim, o objetivo geral do estudo foi compreender os testes de corrida/caminhada de 6 e de 9 minutos e as relações que estes estabelecem com o VO2máx, economia de movimento (EM) e limiar anaeróbio (LA). O estudo propõe uma abordagem de validação de técnica de medida. A amostra foi do tipo não aleatória por conveniência, de corte transversal. Foram avaliados 96 sujeitos, sendo 46 do sexo masculino e 50 do sexo feminino, na faixa etária de 10 a 14 anos de idade. O estágio maturacional foi determinado de acordo com a pilosidade púbica através de Tanner (1962). Os testes de corrida/caminha de 6 e de 9 minutos foram avaliados pela maior distância alcançada no tempo determinado de cada teste. Os componentes da aptidão cardiorrespiratória foram obtidos através de um teste em esteira de carga progressiva até a exaustão, acompanhado pelo ergoespirômetro MedGraphics Cardiorespiratory Diagnostic Systems, modelo MGC/CPX-D. O valor médio de VO2 registrado durante o 4° minuto, a uma velocidade constante, foi considerado o valor de EM. VO2máx que foi obtido pelo maior valor alcançado durante o teste. O limiar ventilatório (LV) foi entendido como o VO2 expresso pelo segundo ponto de inflexão na curva de ventilação e do custo ventilatório de CO2 de cada indivíduo. Para todas as análises estatísticas foi utilizado o programa estatístico SPSS for Windows 10.0. O nível de significância adotado foi de 5%. Os principais resultados apontam que os índices alcançados no teste de 9 minutos (r= 0,632) apresentam melhor relação com o VO2máx de simples razão (ml.kg-1.min-1 ou kg-1) do que os mesmos no teste de 6 minutos (r=0,393). No entanto, o valor de r aumenta para 0,704 e 0,728 nos testes de 6 e de 9 minutos, respectivamente, quando os relacionamos com o VO2máx em expoentes alométricos (kg-0,67). Quanto ao comportamento dessas variáveis durante a puberdade, notamos incremento nos dois testes aeróbios e no VO2máx quando expresso em kg-0,67. No VO2máx (kg-1), os valores médios durante a puberdade se mantiveram estáveis. Quanto às diferenças entre os sexos, percebemos que os valores obtidos pelos meninos superam os das meninas em todas as variáveis. No entanto, percebemos que as diferenças são potencializadas quando expressamos o VO2máx em escalas alométricas (kg-0,67). No âmbito dos componentes da aptidão cardiorrespiratória constatamos que o VO2máx (kg-0,67), aliado a EM (%VO2máx) foram as variáveis que apresentaram maior poder preditivo sobre os testes aeróbios de campo analisados neste estudo, representando geralmente mais de 60% da explicação desses. Já o LV não estabeleceu relações suficientemente capazes de ser apontado como variável preponderante no desempenho dos testes de corrida/caminhada de 6 e de 9 minutos. Dessa forma, podemos concluir que os dois testes analisados são válidos para a avaliação da aptidão cardiorrespiratória se assumirmos que o VO2máx é mais bem representado pelo expoente de massa corporal kg-0,67. Além disso, constatamos que a EM, aliado à capacidade aeróbia máxima é fundamental no desempenho de testes de características aeróbias. Sendo assim, podemos sugerir a utilização do teste de corrida de 6 minutos à professores de educação física como parâmetro da aptidão cardiorrespiratória de seus alunos, pois além de ser um teste simples, de fácil compreensão e que permite sua aplicação em diferentes estruturas físicas, apresentou uma alta relação com o consumo máximo de oxigênio (kg-0,67). / The knowledge about the cardiorespiratory fitness in children and adolescents is a basic strategy of control of the health, considering that low indices of this capacity in this period of age can point important associations with hypokinetic disease in the adult age. However, to evaluate the cardiorespiratory fitness by direct methods demand a high financial cost, specialized people and excessively time. In this perspective, innumerable studies has been considering tests that measure by indirect methods the cardiorespiratory fitness of children and adolescents. Thus, the general objective of this study was to understand the of Run/walk in 6 minutes and Run/walk in 9 minutes tests and the relations that these establish with the VO2max. Moreover, we tried to identify the variables capable to determine the performance of both tests in individuals in the period of infancy and adolescence. The study considers an approach of validation of measuring technique. The sample was a not random type for convenience, with transversal cut analysis. 96 subjects had been evaluated, being 46 masculine and 50 feminine, with ages between 10 and 14 years old. The maturational status was determined by pubic hair according to Tanner (1962). The tests of Run/walk in 6 minutes and Run/walk in 9 minutes had been understood by the biggest distance reached in the definitive time of each test. The components of the cardiorespiratory fitness were gotten through a gradual load test in treadmill until the exhaustion, measured through a gas meter model (MedGraphics Cardiorespiratory Diagnostic Systems – MGC/CPX-D). The average value of VO2 registered during the 4th minute, in a constant speed, was considered the value of movement economy (ME). The VO2max was gotten by the highest value reached during the test. The ventilatory threshold was understood as the VO2 expressed for the second point of inflection in the curve of ventilation and CO2 ventilatory cost for each individual. For all the statistical analyses the statistical program SPSS for Windows 10.0 was used. The level of significance adopted for all the analyses was of 5%. The main results point that the indices reached in the test of 9 minutes (r = 0,632) present better relationship with the VO2max of simple reason (ml.kg-1.min-1 or kg-1) than the same ones in the test of 6 minutes (r=0,393). However, the value of r increases for 0,704 and 0,728 in the tests of 6 and 9 minutes, respectively, when we relate them with the VO2max in allometric exponents (kg-0,67). About the behavior of these variables during the puberty, we notice an increment in the two aerobic tests and in the VO2max expressed in kg-0,67. In the VO2max (kg-1), the average values during the puberty remained steady. About the differences between sexes, we perceive that the values gotten for the boys surpass of the girls in all variables. However, we perceive that the differences are powered when we express the VO2max in allometric scales (kg-0,67). About the components of the cardiorespiratory fitness, we evidence that the VO2max (kg-0,67), ally to the ME (%VO2max) had been the variables that had presented greater predictive power on the field aerobic tests analyzed in this study, representing generally more than 60% of the explanation of these. However, the ventilatory threshold did not establish relationships capable enough to be pointed as the preponderant variable in the performance of Run/walk in 6 minutes and Run/walk in 9 minutes tests. This way, we can conclude that the two analyzed tests are valid for the evaluation of the cardiorespiratory fitness if we assume that the VO2max is better represented by the allometric scales. Moreover, we evidence that the movement economy, ally to the maximum aerobic capacity is basic in the performance of aerobic characteristics tests. Thus, we can suggest the use of the Run/walk in 6 minutes test to any physical education teacher as a parameter of the cardiorespiratory fitness of his students, therefore it is a simple test, of easy understanding, that allows its application in different physical structures and it shows excellent relationship with the maximum oxygen consumption (kg-0,67).
5

Scaling Isometric Mid-Thigh Pull Maximum Strength in Division I Athletes: Are We Meeting the Assumptions?

Suchomel, Timothy J., Nimphius, Sophia, Stone, Michael H. 13 August 2018 (has links)
This study examined the validity of various scaling methods, isometric mid-thigh pull (IMTP) peak force using various scaling methods, and the relationships between IMTP peak force and countermovement jump height. Fifty-one collegiate baseball and soccer athletes performed two maximal IMTPs. Absolute peak force was compared between teams and when data were scaled using ratio (RS), traditional allometric (ALLOTrad), and fitted allometric (ALLOFit) scaling. ALLOTrad and ALLOFit validity was violated because different derived exponents existed for baseball (b = 0.20) and soccer (b = 1.20). Soccer athletes produced greater RS peak force compared to baseball (p = 0.012), while no difference existed with absolute, ALLOTrad or ALLOFit (all p > 0.05) peak force. Moderate relationships existed between body mass and absolute (r = 0.402, p = 0.003) and RS (r = -0.328, p = 0.019) peak force, while trivial relationships existed with ALLOTrad and ALLOFit (both r < -0.10, p > 0.05). Trivial relationships existed between countermovement jump height and absolute, RS, ALLOTrad, and ALLOFit (all r < 0.20, p > 0.05) peak force. The current dataset violated allometric scaling assumptions, making it inappropriate to use ALLOTrad and ALLOFit scaling. Practitioners must understand the assumptions, limitations, and purpose of scaling methods.
6

Peatland Bryophytes in a Changing Environment : Ecophysiological Traits and Ecosystem Function

Granath, Gustaf January 2012 (has links)
Peatlands are peat forming ecosystems in which not fully decomposed plant material builds up the soil. The sequestration of carbon into peat is mainly associated with the bryophyte genus Sphagnum (peat mosses), which dominate and literally form most peatlands. The responses of Sphagnum to environmental change help us to understand peatland development and function and to predict future changes in a rapidly changing world. In this thesis, the overarching aim was to use ecophysiological traits to investigate mechanisms behind the response of Sphagnum to elevated N deposition, and, processes connected to ecosystem shift and ecosystem function of peatlands. Regarding elevated N deposition, three experiments were performed at different scales (country-wide to greenhouse). Independent of scale and species, apical tissue N concentration increased with increasing N input until N saturation was reached. Maximum photosynthetic rate, a trait evaluating photosynthetic capacity, increased with N input and could be well predicted by tissue N concentration. Thus, the physiological responses of Sphagnum to N deposition are often positive and I found no evidence of toxic effects. Production did, however, not increase with N input, and results of the N:P ratio suggested that P limitation, and possibly other elements, might hamper growth under high N input. The effect of P limitation was, in contrast to current view, most pronounced in fast growing species indicating species specific responses to nutrient imbalance. I explored the puzzling, but historically frequently occurring, rich fen to bog ecosystem shift; a shift from a species-rich ecosystem dominated by brown mosses, to a species-poor one with greater carbon storage that is Sphagnum-dominated. The bog-dwelling species of Sphagnum grew well, to our surprise, when in contact with rich fen water but was not a strong competitor compared to rich fen Sphagnum species. If submerged under rich fen water (high pH), the bog Sphagnum species died while rich fen species of Sphagnum were unaffected. These results show that differences in two physiological traits (growth rate and tolerance to flooding) among species, can explain when a peatland ecosystem shift might occur. In the last study, the function of peatlands was related to trade-offs between traits and allometric scaling in Sphagnum. Results suggested that growth strategies are determined by the distribution of Sphagnum relative to the water table in order to minimize periods with suboptimal hydration. Allometric analyses stressed the importance of resource allocation among and within shoots (apical part vs. stem), although the allocation patterns in Sphagnum were not always consistent with those of vascular plants. Interestingly, data indicated a trade-off between photosynthetic rate and decomposition rate among Sphagnum species.
7

Testes de corrida/caminhada de 6 e 9 minutos: validação e determinantes metabólicos em crianças e adolescentes

Lorenzi, Thiago Del Corona January 2006 (has links)
O entendimento da aptidão cardiorrespiratória em crianças e jovens é hoje uma estratégia fundamental de controle da saúde em geral. No entanto, avaliar a aptidão cardiorrespiratória, de forma direta, demanda um custo financeiro alto, pessoal especializado e um tempo excessivo. Nesta perspectiva, inúmeros estudos vêm propondo testes que avaliem, de forma indireta, a aptidão cardiorrespiratória de crianças e jovens. Assim, o objetivo geral do estudo foi compreender os testes de corrida/caminhada de 6 e de 9 minutos e as relações que estes estabelecem com o VO2máx, economia de movimento (EM) e limiar anaeróbio (LA). O estudo propõe uma abordagem de validação de técnica de medida. A amostra foi do tipo não aleatória por conveniência, de corte transversal. Foram avaliados 96 sujeitos, sendo 46 do sexo masculino e 50 do sexo feminino, na faixa etária de 10 a 14 anos de idade. O estágio maturacional foi determinado de acordo com a pilosidade púbica através de Tanner (1962). Os testes de corrida/caminha de 6 e de 9 minutos foram avaliados pela maior distância alcançada no tempo determinado de cada teste. Os componentes da aptidão cardiorrespiratória foram obtidos através de um teste em esteira de carga progressiva até a exaustão, acompanhado pelo ergoespirômetro MedGraphics Cardiorespiratory Diagnostic Systems, modelo MGC/CPX-D. O valor médio de VO2 registrado durante o 4° minuto, a uma velocidade constante, foi considerado o valor de EM. VO2máx que foi obtido pelo maior valor alcançado durante o teste. O limiar ventilatório (LV) foi entendido como o VO2 expresso pelo segundo ponto de inflexão na curva de ventilação e do custo ventilatório de CO2 de cada indivíduo. Para todas as análises estatísticas foi utilizado o programa estatístico SPSS for Windows 10.0. O nível de significância adotado foi de 5%. Os principais resultados apontam que os índices alcançados no teste de 9 minutos (r= 0,632) apresentam melhor relação com o VO2máx de simples razão (ml.kg-1.min-1 ou kg-1) do que os mesmos no teste de 6 minutos (r=0,393). No entanto, o valor de r aumenta para 0,704 e 0,728 nos testes de 6 e de 9 minutos, respectivamente, quando os relacionamos com o VO2máx em expoentes alométricos (kg-0,67). Quanto ao comportamento dessas variáveis durante a puberdade, notamos incremento nos dois testes aeróbios e no VO2máx quando expresso em kg-0,67. No VO2máx (kg-1), os valores médios durante a puberdade se mantiveram estáveis. Quanto às diferenças entre os sexos, percebemos que os valores obtidos pelos meninos superam os das meninas em todas as variáveis. No entanto, percebemos que as diferenças são potencializadas quando expressamos o VO2máx em escalas alométricas (kg-0,67). No âmbito dos componentes da aptidão cardiorrespiratória constatamos que o VO2máx (kg-0,67), aliado a EM (%VO2máx) foram as variáveis que apresentaram maior poder preditivo sobre os testes aeróbios de campo analisados neste estudo, representando geralmente mais de 60% da explicação desses. Já o LV não estabeleceu relações suficientemente capazes de ser apontado como variável preponderante no desempenho dos testes de corrida/caminhada de 6 e de 9 minutos. Dessa forma, podemos concluir que os dois testes analisados são válidos para a avaliação da aptidão cardiorrespiratória se assumirmos que o VO2máx é mais bem representado pelo expoente de massa corporal kg-0,67. Além disso, constatamos que a EM, aliado à capacidade aeróbia máxima é fundamental no desempenho de testes de características aeróbias. Sendo assim, podemos sugerir a utilização do teste de corrida de 6 minutos à professores de educação física como parâmetro da aptidão cardiorrespiratória de seus alunos, pois além de ser um teste simples, de fácil compreensão e que permite sua aplicação em diferentes estruturas físicas, apresentou uma alta relação com o consumo máximo de oxigênio (kg-0,67). / The knowledge about the cardiorespiratory fitness in children and adolescents is a basic strategy of control of the health, considering that low indices of this capacity in this period of age can point important associations with hypokinetic disease in the adult age. However, to evaluate the cardiorespiratory fitness by direct methods demand a high financial cost, specialized people and excessively time. In this perspective, innumerable studies has been considering tests that measure by indirect methods the cardiorespiratory fitness of children and adolescents. Thus, the general objective of this study was to understand the of Run/walk in 6 minutes and Run/walk in 9 minutes tests and the relations that these establish with the VO2max. Moreover, we tried to identify the variables capable to determine the performance of both tests in individuals in the period of infancy and adolescence. The study considers an approach of validation of measuring technique. The sample was a not random type for convenience, with transversal cut analysis. 96 subjects had been evaluated, being 46 masculine and 50 feminine, with ages between 10 and 14 years old. The maturational status was determined by pubic hair according to Tanner (1962). The tests of Run/walk in 6 minutes and Run/walk in 9 minutes had been understood by the biggest distance reached in the definitive time of each test. The components of the cardiorespiratory fitness were gotten through a gradual load test in treadmill until the exhaustion, measured through a gas meter model (MedGraphics Cardiorespiratory Diagnostic Systems – MGC/CPX-D). The average value of VO2 registered during the 4th minute, in a constant speed, was considered the value of movement economy (ME). The VO2max was gotten by the highest value reached during the test. The ventilatory threshold was understood as the VO2 expressed for the second point of inflection in the curve of ventilation and CO2 ventilatory cost for each individual. For all the statistical analyses the statistical program SPSS for Windows 10.0 was used. The level of significance adopted for all the analyses was of 5%. The main results point that the indices reached in the test of 9 minutes (r = 0,632) present better relationship with the VO2max of simple reason (ml.kg-1.min-1 or kg-1) than the same ones in the test of 6 minutes (r=0,393). However, the value of r increases for 0,704 and 0,728 in the tests of 6 and 9 minutes, respectively, when we relate them with the VO2max in allometric exponents (kg-0,67). About the behavior of these variables during the puberty, we notice an increment in the two aerobic tests and in the VO2max expressed in kg-0,67. In the VO2max (kg-1), the average values during the puberty remained steady. About the differences between sexes, we perceive that the values gotten for the boys surpass of the girls in all variables. However, we perceive that the differences are powered when we express the VO2max in allometric scales (kg-0,67). About the components of the cardiorespiratory fitness, we evidence that the VO2max (kg-0,67), ally to the ME (%VO2max) had been the variables that had presented greater predictive power on the field aerobic tests analyzed in this study, representing generally more than 60% of the explanation of these. However, the ventilatory threshold did not establish relationships capable enough to be pointed as the preponderant variable in the performance of Run/walk in 6 minutes and Run/walk in 9 minutes tests. This way, we can conclude that the two analyzed tests are valid for the evaluation of the cardiorespiratory fitness if we assume that the VO2max is better represented by the allometric scales. Moreover, we evidence that the movement economy, ally to the maximum aerobic capacity is basic in the performance of aerobic characteristics tests. Thus, we can suggest the use of the Run/walk in 6 minutes test to any physical education teacher as a parameter of the cardiorespiratory fitness of his students, therefore it is a simple test, of easy understanding, that allows its application in different physical structures and it shows excellent relationship with the maximum oxygen consumption (kg-0,67).
8

Testes de corrida/caminhada de 6 e 9 minutos: validação e determinantes metabólicos em crianças e adolescentes

Lorenzi, Thiago Del Corona January 2006 (has links)
O entendimento da aptidão cardiorrespiratória em crianças e jovens é hoje uma estratégia fundamental de controle da saúde em geral. No entanto, avaliar a aptidão cardiorrespiratória, de forma direta, demanda um custo financeiro alto, pessoal especializado e um tempo excessivo. Nesta perspectiva, inúmeros estudos vêm propondo testes que avaliem, de forma indireta, a aptidão cardiorrespiratória de crianças e jovens. Assim, o objetivo geral do estudo foi compreender os testes de corrida/caminhada de 6 e de 9 minutos e as relações que estes estabelecem com o VO2máx, economia de movimento (EM) e limiar anaeróbio (LA). O estudo propõe uma abordagem de validação de técnica de medida. A amostra foi do tipo não aleatória por conveniência, de corte transversal. Foram avaliados 96 sujeitos, sendo 46 do sexo masculino e 50 do sexo feminino, na faixa etária de 10 a 14 anos de idade. O estágio maturacional foi determinado de acordo com a pilosidade púbica através de Tanner (1962). Os testes de corrida/caminha de 6 e de 9 minutos foram avaliados pela maior distância alcançada no tempo determinado de cada teste. Os componentes da aptidão cardiorrespiratória foram obtidos através de um teste em esteira de carga progressiva até a exaustão, acompanhado pelo ergoespirômetro MedGraphics Cardiorespiratory Diagnostic Systems, modelo MGC/CPX-D. O valor médio de VO2 registrado durante o 4° minuto, a uma velocidade constante, foi considerado o valor de EM. VO2máx que foi obtido pelo maior valor alcançado durante o teste. O limiar ventilatório (LV) foi entendido como o VO2 expresso pelo segundo ponto de inflexão na curva de ventilação e do custo ventilatório de CO2 de cada indivíduo. Para todas as análises estatísticas foi utilizado o programa estatístico SPSS for Windows 10.0. O nível de significância adotado foi de 5%. Os principais resultados apontam que os índices alcançados no teste de 9 minutos (r= 0,632) apresentam melhor relação com o VO2máx de simples razão (ml.kg-1.min-1 ou kg-1) do que os mesmos no teste de 6 minutos (r=0,393). No entanto, o valor de r aumenta para 0,704 e 0,728 nos testes de 6 e de 9 minutos, respectivamente, quando os relacionamos com o VO2máx em expoentes alométricos (kg-0,67). Quanto ao comportamento dessas variáveis durante a puberdade, notamos incremento nos dois testes aeróbios e no VO2máx quando expresso em kg-0,67. No VO2máx (kg-1), os valores médios durante a puberdade se mantiveram estáveis. Quanto às diferenças entre os sexos, percebemos que os valores obtidos pelos meninos superam os das meninas em todas as variáveis. No entanto, percebemos que as diferenças são potencializadas quando expressamos o VO2máx em escalas alométricas (kg-0,67). No âmbito dos componentes da aptidão cardiorrespiratória constatamos que o VO2máx (kg-0,67), aliado a EM (%VO2máx) foram as variáveis que apresentaram maior poder preditivo sobre os testes aeróbios de campo analisados neste estudo, representando geralmente mais de 60% da explicação desses. Já o LV não estabeleceu relações suficientemente capazes de ser apontado como variável preponderante no desempenho dos testes de corrida/caminhada de 6 e de 9 minutos. Dessa forma, podemos concluir que os dois testes analisados são válidos para a avaliação da aptidão cardiorrespiratória se assumirmos que o VO2máx é mais bem representado pelo expoente de massa corporal kg-0,67. Além disso, constatamos que a EM, aliado à capacidade aeróbia máxima é fundamental no desempenho de testes de características aeróbias. Sendo assim, podemos sugerir a utilização do teste de corrida de 6 minutos à professores de educação física como parâmetro da aptidão cardiorrespiratória de seus alunos, pois além de ser um teste simples, de fácil compreensão e que permite sua aplicação em diferentes estruturas físicas, apresentou uma alta relação com o consumo máximo de oxigênio (kg-0,67). / The knowledge about the cardiorespiratory fitness in children and adolescents is a basic strategy of control of the health, considering that low indices of this capacity in this period of age can point important associations with hypokinetic disease in the adult age. However, to evaluate the cardiorespiratory fitness by direct methods demand a high financial cost, specialized people and excessively time. In this perspective, innumerable studies has been considering tests that measure by indirect methods the cardiorespiratory fitness of children and adolescents. Thus, the general objective of this study was to understand the of Run/walk in 6 minutes and Run/walk in 9 minutes tests and the relations that these establish with the VO2max. Moreover, we tried to identify the variables capable to determine the performance of both tests in individuals in the period of infancy and adolescence. The study considers an approach of validation of measuring technique. The sample was a not random type for convenience, with transversal cut analysis. 96 subjects had been evaluated, being 46 masculine and 50 feminine, with ages between 10 and 14 years old. The maturational status was determined by pubic hair according to Tanner (1962). The tests of Run/walk in 6 minutes and Run/walk in 9 minutes had been understood by the biggest distance reached in the definitive time of each test. The components of the cardiorespiratory fitness were gotten through a gradual load test in treadmill until the exhaustion, measured through a gas meter model (MedGraphics Cardiorespiratory Diagnostic Systems – MGC/CPX-D). The average value of VO2 registered during the 4th minute, in a constant speed, was considered the value of movement economy (ME). The VO2max was gotten by the highest value reached during the test. The ventilatory threshold was understood as the VO2 expressed for the second point of inflection in the curve of ventilation and CO2 ventilatory cost for each individual. For all the statistical analyses the statistical program SPSS for Windows 10.0 was used. The level of significance adopted for all the analyses was of 5%. The main results point that the indices reached in the test of 9 minutes (r = 0,632) present better relationship with the VO2max of simple reason (ml.kg-1.min-1 or kg-1) than the same ones in the test of 6 minutes (r=0,393). However, the value of r increases for 0,704 and 0,728 in the tests of 6 and 9 minutes, respectively, when we relate them with the VO2max in allometric exponents (kg-0,67). About the behavior of these variables during the puberty, we notice an increment in the two aerobic tests and in the VO2max expressed in kg-0,67. In the VO2max (kg-1), the average values during the puberty remained steady. About the differences between sexes, we perceive that the values gotten for the boys surpass of the girls in all variables. However, we perceive that the differences are powered when we express the VO2max in allometric scales (kg-0,67). About the components of the cardiorespiratory fitness, we evidence that the VO2max (kg-0,67), ally to the ME (%VO2max) had been the variables that had presented greater predictive power on the field aerobic tests analyzed in this study, representing generally more than 60% of the explanation of these. However, the ventilatory threshold did not establish relationships capable enough to be pointed as the preponderant variable in the performance of Run/walk in 6 minutes and Run/walk in 9 minutes tests. This way, we can conclude that the two analyzed tests are valid for the evaluation of the cardiorespiratory fitness if we assume that the VO2max is better represented by the allometric scales. Moreover, we evidence that the movement economy, ally to the maximum aerobic capacity is basic in the performance of aerobic characteristics tests. Thus, we can suggest the use of the Run/walk in 6 minutes test to any physical education teacher as a parameter of the cardiorespiratory fitness of his students, therefore it is a simple test, of easy understanding, that allows its application in different physical structures and it shows excellent relationship with the maximum oxygen consumption (kg-0,67).
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PREDICTION OF HUMAN SYSTEMIC, BIOLOGICALLY RELEVANT PHARMACOKINETIC (PK) PROPERTIES BASED ON QUANTITATIVE STRUCTURE PHARMACOKINETIC RELATIONSHIPS (QSPKR) AND INTERSPECIES PHARMACOKINETIC ALLOMETRIC SCALING (PK-AS)

Badri, Prajakta 01 January 2010 (has links)
This research developed validated QSPKR and PK-AS models for predicting human systemic PK properties of three, preselected, pharmacological classes of drugs, namely opioids, β-adrenergic receptor ligands (β-ARL) and β-lactam antibiotics (β-LAs) using pertinent human and animal systemic PK properties (fu,, CLtot, Vdss, fe) and their biologically relevant unbound counterparts from the published literature, followed by an assessment of the effect of different molecular descriptors on these PK properties and on the PK-AS slopes for CLtot and Vdss from two species (rat and dog). Lipophilicity (log (D)7.4) and molecular weight (MW) were found to be the most statistically significant and biologically plausible, molecular properties affecting the biologically relevant, systemic PK properties: For compounds with log (D)7.4 > -2.0 and MW < 350 D (e.g., most opioids and β-ARL), increased log (D)7.4 resulted in decreased fu and increased Vdssu, CLtotu and CLnonrenu, indicating the prevalence of hydrophobic interactions with biological membrane/proteins. As result, the final QSPKR models using log (D)7.4 provided acceptable predictions for fu, Vdssu, CLtotu and CLnonrenu. CLnonrenu and CLtotu. For both the datasets, inclusion of drugs undergoing extrahepatic clearance worsened the QSPKR predictions. For compounds with log (D)7.4 < -2.0 and MW > 350 D (e.g., β-LA), increased MW (leading to more hydrogen bond donors/acceptors) resulted in a decrease in fu, likely indicating hydrogen bonding interactions with plasma proteins. In general, it was more difficult to predict PK parameters for β-LAs, as their Vdssu approached plasma volume and CLrenu and CLnonrenu were low - as a result of their high hydrophilicity and large MW, requiring specific drug transporters for distribution and excretion. The PK-AS analysis showed that animal body size accounted for most of the observed variability (r2> 0.80) in systemic PK variables, with single species methods, particularly those using dog, gave the best predictions. The fu correction of PK variables improved goodness of fit and predictability of human PK. There were no apparent effects of molecular properties on the predictions. CLren, CLrenu, CLnonren, and CLnonrenu were the most difficult variables to predict, possibly due to the associated interspecies differences in the metabolism, renal and hepatobiliary drug transporters.
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Atualizações sobre biologia e manejo conservacionista em primatas atelídeos da espécie Lagothrix cana

Carneiro, Marcelo Rocha January 2018 (has links)
Orientador: Lígia Souza Lima Silveira da Mota / Resumo: Este trabalho relata preliminarmente, a caracterização genética de primatas da espécie Lagothrix cana (macacos-barrigudos cinza), por meio de sequenciamento genético e análise de DNA mitocondrial do segmento D-Loop, após extração do DNA com a utilização da técnica do fenol/clorofórmio. Aliado a isso, é reportada uma revisão bibliográfica acerca dos dados anatômicos, fisiológicos, clínicos, reprodutivos e comportamentais, já disponíveis em literatura especializada sobre a espécie. Também, é validado um protocolo de contenção farmacológica executável e eficiente para procedimentos da rotina dos profissionais que desenvolvem ações, na área de medicina da conservação e atuam com primatas cativos deste gênero. Foram utilizados 21 primatas adultos da espécie Lagothrix cana (macaco-barrigudo), pesando 5,24 ± 1,66 kg, sendo 14 fêmeas e sete machos, para a validação deste protocolo. Os fármacos utilizados foram a tiletamina, o zolazepam, a atropina e a detomidina, em associação, com suas doses calculadas por meio de extrapolação alométrica interespecífica. Os fármacos foram combinados numa preparação concentrada que foi denominada “ZAD-50” (Zoletil/50® + Atropina + Detomidina), obtendo-se volume final exato de 3,0 ml de ZAD-50, com a associação de fármacos numa concentração que permite a contenção farmacológica de um mamífero placentário que pese 10,0 Kg com um volume de 0,6 ml, por exemplo. 567 pares de bases de DNA mitocondrial foram utilizadas, e conseguiu-se caracterizar os indiví... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This manuscript reports, at first, the genetic characterization of primates Lagothrix cana (“gray wooly-monkeys”), by means of DNA sequencing and mitochondrial DNA analysis of the D-Loop section, after the extraction with the phenol/chloroform method, described by Sambrook e Russel (2001). In addition, is related a wide vision of the scientific data available bibliographic about the anatomical, physiological, medical, reproductive and behavioural existing data, about the specie. Also is related a performable and efficient chemical restraint protocol to permit usual procedures for professionals of conservation medicine, who works with captive primates of Lagothrix sp. genus. The study evaluate the chemical restraint and field anesthesia of 21 wooly-monkeys (Lagothrix cana: Atelidae) weighing 5,24 ± 1,66 kg, being fourteen female and seven male. There was employed the combination of tiletamine, zolazepam, atropine, and detomidine, in allometrically scaled dosages. The drugs were combined in a concentrate preparation called “ZAD-50” (Zoletil/50® + Atropine + Dormiun-V®). and give an accurate final volume of 3.0 mL of ZAD-50, with the combination of drugs at a concentration that allows the pharmacological restraint of a placental mammal weighing 10.0 kg with a volume of 0.6 ml, for example. 567 base pairs of mitochondrial DNA samples was utilized and was realized the classification of the specimens as Lagothrix cana, after the comparison with L. poepigii and L. lagothricha data. ... (Complete abstract click electronic access below) / Doutor

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