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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.
321

Caracterização proteômica do fígado de bovinos Nelore divergentes para eficiência alimentar / Proteomic characterization of the liver of Nellore cattle divergent for feed efficiency

Fonseca, Leydiana Duarte 16 October 2018 (has links)
A alimentação é um dos custos mais relevantes da produção de bovinos de corte e melhorar a eficiência na utilização de nutrientes é essencial para a viabilidade da produção, dado o atual cenário de crescente demanda por proteína animal e mercado altamente competitivo. Nesse contexto, a proteômica surge como uma importante ferramenta na busca por alternativas que aumentem a eficiência alimentar (EA) de bovinos de corte. Assim, o objetivo deste trabalho é caracterizar o proteoma hepático de bovinos Nelore classificados quanto à EA. Noventa e oito animais foram avaliados em projeto anterior e seis indivíduos de baixa (BEA) e alta eficiência (AEA) tiveram amostras de fígado coletadas no abate, congeladas em Nitrogênio líquido e armazenadas em freezer à -80 ºC. Após a extração e precipitação das proteínas, as amostras foram processadas por duas abordagens distintas: digeridas com tripsina em solução e analisadas em cromatógrafo líquido de alta eficiência acoplado ao espectrômetro de massas (LC-MS/MS); e previamente separadas em gel para posterior digestão e análise (GeLC-MS/MS). Os dados adquiridos por LC-MS/MS foram analisados com o programa MaxQuant contra os bancos de Bos taurus e Bos indicus do Uniprot para identificação das proteínas, e os resultados analisados com o programa Perseus. Os dados obtidos por GeLC-MS/MS foram analisados com os programas Mascot Distiller e X! Tandem e validados no Scaffold Q+ contra o banco Bos taurus do Uniprot e os resultados analisados com os programas Scaffold Q+ e Perseus. Para abordagem LC-MS/MS, 376 proteínas foram quantificadas e submetidas à análise de abundância diferencial e construção de redes de co-expressão pelo WGCNA, identificando 42 proteínas diferencialmente abundantes (PDAs, p < 0,05) e três módulos significativamente associados à EA. Pela abordagem GeLC-MS/MS foram quantificadas 102 proteínas, das quais cinco foram PDAs (p-valor < 0,05). Três PDAs foram comuns às duas abordagens proteômicas. As proteínas associadas negativamente à EA foram principalmente relacionadas à síntese lipídica, degradação de ácidos graxos, enzimas do sistema do citocromo P450 e processos oxidativos. Por outro lado, as proteínas positivamente relacionadas à EA, foram principalmente envolvidas em processamento e enovelamento de proteínas, além de proteínas atuantes na manutenção da integridade e restauração do citoesqueleto celular. Em ambos os grupos também foram identificadas proteínas que atuam no sistema imunológico e resposta inflamatória. Estes resultados comprovam experimentos anteriores do grupo e demonstram a existência de diferença entre os proteomas do fígado de animais eficientes e ineficientes. / Feeding is one of the most relevant cost of beef cattle production and improving nutrient utilization efficiency is essential for the viability of production, given the current scenario of increasing demand for animal protein and highly competitive market. In this context, proteomics appears as an important tool in the search for alternatives that increase the feed efficiency (FE) of beef cattle. Thus, the aim of this work is to characterize the hepatic proteome of beef cattle selected for divergent FE. Ninety-eight animals were evaluated in a previous project, and six individuals with low feed efficiency (LFE) and six with high feed efficiency (HFE) had liver samples collected at slaughter, frozen in liquid Nitrogen and stored in a freezer at -80 °C. After protein extraction and precipitation, the samples were processed by two different approaches: digested with trypsin in solution and analyzed in a high efficiency liquid chromatograph coupled to the mass spectrometer (LC-MS/MS); and previously separated in gel for further digestion and analysis (GeLC-MS/MS). Data acquired by LC-MS/MS were analyzed with MaxQuant software against the Bos taurus and Bos indicus Uniprot databases for proteins identification and the results analyzed with Perseus software. The data obtained by GeLC-MS/MS were analyzed with the softwares Mascot Distiller and X! Tandem and validated in the Scaffold Q+, against Bos taurus Uniprot database and results analyzed with the softwares Scaffold Q+ and Perseus. For the LC-MS/MS approach, 376 proteins were quantified and submitted to differential abundance analysis and co-expression networks by WGCNA, identifying 42 differentially abundant proteins (DAPs, p < 0.05) and three modules significantly associated with FE. For the GeLC-MS/MS approach, 102 proteins were quantified, of which five were DAPs (p-value < 0.05). Three DAPs were common to both proteomics approaches. Proteins negatively associated with FE were mainly related to lipid synthesis, degradation of fatty acids, cytochrome P450 system enzymes and oxidative processes. On the other hand, proteins positively related to FE were mainly involved in protein processing and folding, maintenance of the integrity and restoration of the cellular cytoskeleton. In both groups were also identified proteins that play a role on the immune system and inflammatory response. These results prove previous experiments of the group and demonstrate the existence of difference between liver proteomes of efficient and inefficient animals.
322

Avaliação da composição corporal por espectroscopia por bioimpedância em pacientes com síndrome nefrótica / Evaluation of the body composition by spectroscopy by bioimpedance in patients with nephrotic syndrome

Aline Scharr Rodrigues 06 November 2018 (has links)
Síndrome nefrótica é definida pela presença simultânea de edema sistêmico, hipoalbuminemia e proteinúria intensa. Vários componentes da composição corporal, principalmente relacionados à água corporal, sofrem rápidas e frequentes alterações nessa síndrome. A espectroscopia por bioimpedância (BIS) é um método de fácil execução, baixo custo, que pode ser repetido e praticamente isento de riscos que permite avaliar água corporal, massa magra e gordura corporal e tem sido pouco utilizado na síndrome nefrótica. Objetivo. Avaliar as alterações da água e de outros componentes da composição corporal através da BIS em pacientes com síndrome nefrótica. Métodos. Pacientes foram avaliados na ocasião da biópsia renal e no desfecho com ou sem remissão do edema. Foram medidos o peso corporal, albumina sérica e proteinúria de 24 h e, pela BIS, variáveis relacionadas à água corporal e a outros parâmetros de composição corporal. Resultados. Foram estudados 17 pacientes (idade: 51,1 + 17,4 anos) com síndrome nefrótica. Dez pacientes obtiveram remissão do edema (grupo R), sendo que em nove ocorreu também remissão da síndrome nefrótica. Em sete pacientes o edema permaneceu presente, sem remissão (grupo SR). A variação entre a primeira e a segunda medida para a sobrecarga hídrica foi de -5,4 L (-8,5 L; -1,8 L) no grupo R e de 0,0 L (-1,1 L; 1,2 L) no grupo SR (p < 0,05). A água corporal total variou de -4,75 L (- 10,20 L; -2,50 L) e de 4,80 L (-1,30 L; 6,10 L) nos grupos R e SR, respectivamente (p < 0,05), e a água extracelular variou de -5,90 L (-10,10 L; -0,42 L) e de 1,20 L (-0,80 L; 2,70 L) nos mesmos grupos (p < 0,05). Não houve diferença estatisticamente significante na variação entre as duas avaliações nos grupos R e SR para a água intracelular, massa de tecido magro, massa de tecido adiposo, massa gorda total e massa celular corporal. A variação do ângulo de fase entre as avaliações foi de 1,55° (0,41°; 2,24°) no grupo R e 0,10° (-0,28°; 0,46°) no grupo SR (p < 0,05). Houve correlação estatisticamente significante entre cada variável definidora da síndrome nefrótica (peso corporal, proteinúria e albumina sérica) versus sobrecarga hídrica, água corporal total, água extracelular e ângulo de fase, mas não versus as demais medidas de composição corporal obtidas pela BIS. Conclusão. A espectroscopia por bioimpedância mostrou-se eficiente em detectar mudanças da água corporal e do ângulo de fase em pacientes com síndrome nefrótica, mas não para identificar variações relacionadas à massa de tecido magro, massa de tecido adiposo, massa gorda total e massa celular corporal. . / Nephrotic syndrome is established by the simultaneous presence of systemic edema, hypoalbuminemia, and severe proteinuria. Several components of the body composition, mainly related to the body fluid, undergo to rapid and frequent changes in this syndrome. Spectroscopy by bioimpedance (BIS) is a reliable, cost-effective and easy-to-perform method to evaluate body water, adipose tissue mass, and body cell mass. Despite these advantages, BIS has barely been used to evaluate patients with nephrotic syndrome. Aims. To evaluate body fluid variable changes and other components of the body composition in patients with nephrotic syndrome by bioimpedance spectroscopy. Methods. Patients were studied in two moments: at the occasion of the renal biopsy (1st evaluation), and at the end-point (2nd evaluation). Patients were grouped according to they reached remission (Group R) or remained without remission (Group WR) of the edema at the 2nd evaluation. Body weight, serum albumin and 24 hours proteinuria were measured at the two time-points, as well as other variables associated with body fluid and other components of the body composition obtained by the BIS. Results. Seventeen patients (age: 51,1 + 17,4 years-old) with nephrotic syndrome were studied. Ten patients reached remission of the edema while nine of them were also in remission of the nephrotic syndrome. Seven patients remained with edema at the end-point. The variation between the 1st and the 2nd measurement for the overhydration was of -5,4 L (-8,5L; -1,8L) at the group R and of 0,0 (-1,1 L; 1,2 L) at the group NR (p < 0,05). Total body water changes were of -4,75 L (-10,20 L; -2,50 L) and of 4,80 L (-1,30 L; 6,10 L) at the groups R and WR, respectively (p < 0,05), and the extracellular water changed of the -5,90 L (-10,10 L; -0,42 L) and of 1,20 L (-0,80 L; 2,70 L) at the same groups, respectively (p < 0,05). There was no statistically significant difference in the variation between the two evaluations for the groups R and NR for intracellular water, lean tissue mass, fat mass, adipose tissue mass, and body cell mass. The variation of the phase angle between the two evaluations was of the 1,55° (0,41°; 2,24°) at the group R and 0,10° (-0,28°; 0,46°) at the group WR (p < 0,05). There was a statistically significant correlation between each related nephrotic syndrome variable compared with overhydration, total body water, extracellular water, and phase angle, but no difference when compared with the other variables related to the body composition measured by the BIS. Conclusion. The spectroscopy by bioimpedance was efficient to measure body water changes and the phase angle in patients with nephrotic syndrome. However, the BIS could not detect changes related to the intracellular water, lean tissue mass, fat mass, adipose tissue mass, and body cell mass.
323

Efeitos da história de privação no desempenho operante, no peso e no consumo de água e alimento / Effects of deprivation history on operant performance, on weight and on water and food consumption

Rocha, Julia Guedes da 27 June 2008 (has links)
Made available in DSpace on 2016-04-29T13:18:09Z (GMT). No. of bitstreams: 1 Julia Guedes da Rocha.pdf: 1447284 bytes, checksum: a8b9acdcd986a43f254e4072f1b96eb9 (MD5) Previous issue date: 2008-06-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This thesis s intent was to verify the effects of deprivation history on operant performance, on weight and on water and food consumption in rats. Another purpose was evaluate the effects of the experimental sessions on weight and on water and food consumption, with subjects under different deprivation history. Twelve rats were divided in 4 groups of three rats and each group was submitted to different deprivation history. All subjects were submitted to a preparing phase, which consisted of a 1st condition, when they had free access to the food, and a 2nd condition, in which the subjects were food deprived. After the preparing phase, the history phase began. Then, each group was submitted to different alternations between free access and food deprivation. When they were deprived, the subjects had one hour of food access daily. Two of the three subjects of each group had been on VI60 s sessions since the 2nd condition of the preparing phase. The results suggest: (1) the subjects gained more weight in the beginning of the 1st return to free access condition than the 2nd return to that condition; on each exposure to deprivation, the lost of weight took less time than the previous exposure; (2) the operant box sessions seemed to be an important variable on weight maintenance and recovery of some subjects; (3) the water consumption often decreased during deprivation; (4) the caloric ingestion decreased during deprivation and increased when subjects returned to free access conditions, to values beyond that registered in the 1st condition. After that, there is a decrease in caloric ingestion, bigger on each return to free access condition; (5) the previous condition, free access or deprivation, seems to produce effects on the first experimental sessions of each new condition / O objetivo deste estudo foi verificar os possíveis efeitos produzidos por diferentes histórias de privação no desempenho operante, no peso e no consumo de água e alimento em ratos. Outro objetivo foi avaliar os efeitos de sessões experimentais na caixa operante no peso e no consumo de água e alimento dos sujeitos com diferentes privações. Para tanto, 12 ratos foram divididos em 4 grupos e cada um destes passou por diferentes histórias de privação. Todos os sujeitos passaram pela mesma fase de preparação, que consistiu em uma 1ª condição, na qual os sujeitos estavam ad lib, e em uma 2ª condição, em que os sujeitos estavam privados de alimento. Após a fase de preparação, teve início a fase de história, na qual cada grupo passou por diferentes alternações entre condições ad lib e privação. Quando privados, os animais tinham uma hora de acesso diário ao alimento. Dois dos três sujeitos de cada grupo passaram por sessões de VI60 s, a partir da 2ª condição da fase de preparação. Os resultados sugerem que: (1) os sujeitos tiveram um ganho maior de peso no início da 1ª vez que retornavam à situação de livre acesso ao alimento do que 2ª vez que foram expostos à condição ad lib e perderam peso durante menos tempo a cada nova exposição à privação; (2) as sessões na caixa operante pareceram uma variável importante na manutenção e recuperação do peso de alguns sujeitos; (3) em geral, o consumo de água diminuiu durante a privação; (4) a ingestão calórica aumentou, quando os sujeitos retornaram à condição ad lib, para valores além dos obtidos na 1ª condição (ad lib). Logo depois, observa-se uma diminuição da ingestão calórica, mais acentuada a cada retorno à situação de livre acesso; (5) a condição anterior, ad lib ou privação, parece ter efeitos nas primeiras sessões experimentais de cada nova condição
324

Differential Effects of Chronic Low Calorie Sweetener Consumption on Body Weight, Glycemia, and Ingestive Behavior

Kelly A. Higgins (5929742) 17 January 2019 (has links)
<p>Low calorie sweeteners (LCS) provide sweetness with little to no energy. Each sweetener has a unique chemical structure that possesses unique sensory and functional characteristics. While LCS are generally considered in aggregate, these unique chemical structures have potential implications for sensory, metabolic, and behavioral differences that may impact body weight and glycemia. Therefore, two, twelve-week experiments were conducted to determine the effect of chronic LCS consumption on body weight, glycemia, and ingestive behaviors. </p> <p>The first experiment investigated the differential effects of four LCS (saccharin, aspartame, rebaudioside A, and sucralose) and sucrose consumed for twelve weeks on body weight, glycemia, and ingestive behaviors among healthy adults with overweight or obesity (body mass index (BMI) between 25 and 40 kg/m<sup>2</sup>). In a parallel-arm design, 154 participants were randomly assigned to consume 1.25 to 1.75L of beverage sweetened with 1 of the 5 sweeteners daily for 12 weeks. Body weight was measured every two weeks; energy intake, energy expenditure, and appetite were assessed every 4 weeks; and glucose tolerance was measured at baseline and week 12. Every four weeks, participants completed 24-hour urine collections to determine study compliance via PABA excretion. Sucrose and saccharin consumption led to increased body weight across the 12-week intervention (Δ weight = +1.85 and +1.18kg, p ≤ 0.02) and did not differ from each other. While there was no significant change in body weight with consumption of the other LCS treatments compared to baseline, changes in weight in comparison to the sucrose treatment (sucrose – LCS) were significantly different for aspartame, rebA, and sucralose after 12 weeks (weight difference = 1.13, 1.25, 2.63kg, respectively; p ≤ 0.03). In addition, change in body weight at week 12 was significantly lower between sucralose and all other LCS (weight difference ≥ - 1.37 kg, p=0.008).</p> <p>The second experiment investigated the effect of daily aspartame ingestion on glycemia, body weight, and appetite. One hundred lean (BMI between 18 and 25 kg/m<sup>2</sup>) adults were randomly assigned to consume 0, 350, or 1050 mg aspartame/day for twelve weeks in a parallel-arm design. This experiment followed a similar protocol but measured body weight and blood pressure weekly and contained a 240-min glucose-tolerance test (OGTT) with measurements of selected hormones at baseline and week 12. Participants also collected 24-h urine samples every four weeks. There were no group differences for glucose, insulin, resting leptin, glucagon-like peptide 1, or gastric inhibitory peptide at baseline or week 12. There also were no effects of aspartame ingestion on appetite, body weight, or body composition. </p> <p>These trials demonstrate that all LCS contribute negligible energy but should not be aggregated because of their differing effects on body weight. Sucrose and saccharin consumption significantly increased body weight compared to aspartame, rebA, and sucralose. This differential change in body weight among LCS indicates individual LCS likely exert different physiological responses beyond the contribution of sweetness with negligible energy. Saccharin, rebA, sucralose, and aspartame (ingested at three doses) for twelve weeks had no effect on glycemia. These data do not support the view that LCS are problematic for the management of glycemia. If substantiated through additional testing, findings from this trial have implications for consumers, food industry, clinicians, and policy makers. Some LCS may not hold the anticipated beneficial effects on body weight (e.g., saccharin) and positive effects of one LCS (sucralose) may be attenuated if combined with select other LCS. Going forward it will be important to consider each LCS as a distinct entity with respect to its potential health effects.</p>
325

Caracterização proteômica do fígado de bovinos Nelore divergentes para eficiência alimentar / Proteomic characterization of the liver of Nellore cattle divergent for feed efficiency

Leydiana Duarte Fonseca 16 October 2018 (has links)
A alimentação é um dos custos mais relevantes da produção de bovinos de corte e melhorar a eficiência na utilização de nutrientes é essencial para a viabilidade da produção, dado o atual cenário de crescente demanda por proteína animal e mercado altamente competitivo. Nesse contexto, a proteômica surge como uma importante ferramenta na busca por alternativas que aumentem a eficiência alimentar (EA) de bovinos de corte. Assim, o objetivo deste trabalho é caracterizar o proteoma hepático de bovinos Nelore classificados quanto à EA. Noventa e oito animais foram avaliados em projeto anterior e seis indivíduos de baixa (BEA) e alta eficiência (AEA) tiveram amostras de fígado coletadas no abate, congeladas em Nitrogênio líquido e armazenadas em freezer à -80 ºC. Após a extração e precipitação das proteínas, as amostras foram processadas por duas abordagens distintas: digeridas com tripsina em solução e analisadas em cromatógrafo líquido de alta eficiência acoplado ao espectrômetro de massas (LC-MS/MS); e previamente separadas em gel para posterior digestão e análise (GeLC-MS/MS). Os dados adquiridos por LC-MS/MS foram analisados com o programa MaxQuant contra os bancos de Bos taurus e Bos indicus do Uniprot para identificação das proteínas, e os resultados analisados com o programa Perseus. Os dados obtidos por GeLC-MS/MS foram analisados com os programas Mascot Distiller e X! Tandem e validados no Scaffold Q+ contra o banco Bos taurus do Uniprot e os resultados analisados com os programas Scaffold Q+ e Perseus. Para abordagem LC-MS/MS, 376 proteínas foram quantificadas e submetidas à análise de abundância diferencial e construção de redes de co-expressão pelo WGCNA, identificando 42 proteínas diferencialmente abundantes (PDAs, p &lt; 0,05) e três módulos significativamente associados à EA. Pela abordagem GeLC-MS/MS foram quantificadas 102 proteínas, das quais cinco foram PDAs (p-valor &lt; 0,05). Três PDAs foram comuns às duas abordagens proteômicas. As proteínas associadas negativamente à EA foram principalmente relacionadas à síntese lipídica, degradação de ácidos graxos, enzimas do sistema do citocromo P450 e processos oxidativos. Por outro lado, as proteínas positivamente relacionadas à EA, foram principalmente envolvidas em processamento e enovelamento de proteínas, além de proteínas atuantes na manutenção da integridade e restauração do citoesqueleto celular. Em ambos os grupos também foram identificadas proteínas que atuam no sistema imunológico e resposta inflamatória. Estes resultados comprovam experimentos anteriores do grupo e demonstram a existência de diferença entre os proteomas do fígado de animais eficientes e ineficientes. / Feeding is one of the most relevant cost of beef cattle production and improving nutrient utilization efficiency is essential for the viability of production, given the current scenario of increasing demand for animal protein and highly competitive market. In this context, proteomics appears as an important tool in the search for alternatives that increase the feed efficiency (FE) of beef cattle. Thus, the aim of this work is to characterize the hepatic proteome of beef cattle selected for divergent FE. Ninety-eight animals were evaluated in a previous project, and six individuals with low feed efficiency (LFE) and six with high feed efficiency (HFE) had liver samples collected at slaughter, frozen in liquid Nitrogen and stored in a freezer at -80 °C. After protein extraction and precipitation, the samples were processed by two different approaches: digested with trypsin in solution and analyzed in a high efficiency liquid chromatograph coupled to the mass spectrometer (LC-MS/MS); and previously separated in gel for further digestion and analysis (GeLC-MS/MS). Data acquired by LC-MS/MS were analyzed with MaxQuant software against the Bos taurus and Bos indicus Uniprot databases for proteins identification and the results analyzed with Perseus software. The data obtained by GeLC-MS/MS were analyzed with the softwares Mascot Distiller and X! Tandem and validated in the Scaffold Q+, against Bos taurus Uniprot database and results analyzed with the softwares Scaffold Q+ and Perseus. For the LC-MS/MS approach, 376 proteins were quantified and submitted to differential abundance analysis and co-expression networks by WGCNA, identifying 42 differentially abundant proteins (DAPs, p &lt; 0.05) and three modules significantly associated with FE. For the GeLC-MS/MS approach, 102 proteins were quantified, of which five were DAPs (p-value &lt; 0.05). Three DAPs were common to both proteomics approaches. Proteins negatively associated with FE were mainly related to lipid synthesis, degradation of fatty acids, cytochrome P450 system enzymes and oxidative processes. On the other hand, proteins positively related to FE were mainly involved in protein processing and folding, maintenance of the integrity and restoration of the cellular cytoskeleton. In both groups were also identified proteins that play a role on the immune system and inflammatory response. These results prove previous experiments of the group and demonstrate the existence of difference between liver proteomes of efficient and inefficient animals.
326

Relação entre diferentes índices de eficiência alimentar e características de desempenho, carcaça e termografia em bovinos Nelore confinados / Relationship of different feed efficiency indexes with performance, carcass traits and thermography in feedlot Nellore cattle

Vicente Luiz Macêdo Buarque 23 March 2018 (has links)
Esse trabalho foi desenvolvido para avaliar a relação entre diferentes medidas de eficiência utilizadas na bovinocultura de corte e as características de desempenho, carcaça e termografia infravermelho (TIV) em bovinos Nelore confinados. Foram utilizados 111 bovinos Nelore, machos não-castrados contemporâneos, com idade aproximada de 16±2 meses, peso corporal médio de 420±55 kg. Os animais foram confinados por 91 dias, sendo 21 dias de adaptação às instalações e à dieta. A dieta foi a mesma para todos os animais e composta por 73% de concentrado e 27% de volumoso. O consumo de matéria seca (CMS) foi avaliado diariamente, enquanto o peso vivo, medidas de ultrassom para avaliação de características de carcaça e imagens de TIV foram realizadas a cada 28 dias até o dia 70. A partir dos dados de CMS foram calculados o consumo alimentar residual (CAR), ganho de peso residual (GPR), consumo e ganho residual (CGR). Após a obtenção dos dados foram realizadas análises de associação (correlação e regressão) visando à identificação de possíveis relações entre as diferentes características com as medidas de eficiência. Não houve correlação entre o GMD com o CAR (r=0,001), e com o CGR (r= 0,114), enquanto o GPR apresentou correlação com o GMD (r= 0,588). O CMS foi correlacionado com o CAR (r= 0,612) e com o CGR (r= -0,532) e não houve correlação com o GPR (r= -0,002). Não houve correlação entre as medidas de eficiência com as características de peso vivo inicial (PVI) e peso vivo final (PV70). Dentre as características de carcaça avaliadas ao abate, apenas o GPR apresentou correlação com a gordura renal pélvica e inguinal (GRPIkg), trato gastrintestinal (TGIkg) e peso de corpo vazio (PCVZkg) na ordem de (r= 0,240), (r= 0,226) e (r= 0,210), respectivamente. Entre as medidas de carcaça avaliadas por ultrassom, apenas a espessura de gordura subcutânea (EGS) final apresentou correlação com o CAR (r= 0,348), GPR (r= -0,188) e CGR (r= -0,340), enquanto a espessura de gordura da picanha (EGP) final apresentou correlação apenas com o CAR (r= 0,233) e CGR (r= -0,200). Houveram correlações entre o ganho de EGS e o CAR (r= 0,371) e CGR (r= 0,345), porém o ganho de EGP se correlacionou apenas com o CAR (r= 0,202). Não foram observadas correlações entre as medidas de eficiência e TIV, porém, esses resultados podem ter sido influenciados pelos fatores ambientais. A AOL não apresentou correlação com nenhuma das medidas de eficiência avaliadas. Dessa forma conclui-se que, o CAR é a medida que mais se aplica n seleção de animais de menor CMS, sem prejuízos as características de desempenho. Adicionalmente, o CAR e CGR selecionam animais mais eficientes em termos de menor consumo, enquanto que o GPR seleciona animais de maior GMD. / The aim of the present study was to evaluate the relationship between different efficiency indexes used in beef cattle and performance, carcass traits and thermography in Nellore cattle at the feedlot system. A total of 111 Nellore male, with around 16±2 months age and 420±55 kg of body weight, were used. The animals were confined for 91 days, with 21 days for adaptation to the facilities and diet. The diet was the same for all animals, and composed by 73% of concentrate and 27% of roughage. Dry matter intake (DMI) was evaluated daily, and performance, ultrasound measurements and infrared thermography images were performed every 28 days until day 70. From the DMI measurements, residual feed intake (RFI), residual weight gain (RWG), residual intake and body weight gain (RIG) were calculated. From the data obtained, association analysis (correlation and regression) were performed to identify the possibilities relationships between the different characteristics with the efficiency measures. The ADG showed no correlation with RFI (r= 0.001) and RIG (r= 0.114); however, the RWG was correlated with ADG (r= 0.588). DMI was correlated with RFI (r= 0.612) and RIG (r= -0.532) and there was no correlation with RWG (r= -0.002) There was no correlation between efficiency measures with initial body weight (IBW) and final body weight (BW70). For carcass traits, evaluated at slaughter, only the RWG showed correlation with pelvic renal and inguinal fat (PRIFkg), gastrintestinal tract (GITkg) and empty body weight (EBWkg) in order of the (r= 0.240), (r= 0.226) and (r= 0.210), respectively. For carcass measurements evaluated by ultrasound, the final backfat thickness (BFT) showed correlation with RFI (r= 0.348), RWG (r= -0.188) and RIG (r= -0.340), while final subcutaneous fat thickness on the Biceps femoris muscle (BFTP8) showed a correlation with RFI (r= 0.233) and RIG (r= -0.220). In addition, BFT gain has been also correlated with RFI (r= 0.371) and RIG (r= 0.345); however, the BFTP8 gain only showed correlation with the RFI (r=0.202). There was no correlation between efficiency measures and the infrared thermography (IRT). The rib eye area (REA) showed no correlation with any the efficiency measures evaluated. In conclusion, the RFI is the measure that most applies in the selection of animals of smaller DMI, without damage to the performance traits. In addition, the RFI and RIG can promoter the selection of more efficient animals by lower consumer, whereas the RWG selected great ADG animals.
327

Efeito do protocolo de estressores e da privação de água sobre o consumo de sacarose, o peso corporal e o consumo de alimento e água em ratos / Effects of a stress protocol and water deprivation on sucrose consumption, body weight and food and water intake by rats

Clarissa Moreira Pereira 17 April 2015 (has links)
O Chronic Mild Stress (CMS) é um modelo animal de depressão estudado para investigação das causas e dos atenuadores deste problema. Nele, ratos são submetidos a um protocolo de estressores moderadamente aversivos de maneira crônica. É observada diminuição na ingestão e preferência por substância líquida doce por conta desta submissão. Em estudo sobre o papel da privação de alimento e água no conjunto de estressores, Pereira e Sério (2010) não observaram os efeitos de diminuição na ingestão e preferência por sacarose. É levantada a possibilidade de que a privação de água e alimento a que os sujeitos foram submetidos previamente ao protocolo poderia ter sido responsável pelas diferenças encontradas, já que diferiu em muitos aspectos do realizado por Willner et al. (1987). O objetivo do presente estudo foi o de investigar o papel da privação de água no protocolo de estressores. Três grupos de sujeitos foram propostos: Grupo Protocolo (submetido ao protocolo completo), Grupo Privação (submetido apenas à privação de água presente no protocolo) e Grupo Controle (submetido apenas aos testes semanais de ingestão e preferência). Foram realizados testes de ingestão e preferência por sacarose antes, durante e depois do protocolo ou da privação e aferições semanais de peso e consumo de alimento e água. Como resultado o consumo de sacarose apresentou queda com o decorrer dos testes tanto para os Grupos Protocolo e Privação quanto para o Grupo Controle. Ou seja, não é possível atribuir a nenhum dos procedimentos (protocolo ou privação) a queda observada nessa medida. O peso corporal apresentou queda também para os três grupos assim que iniciado o procedimento de privação precedente ao teste. Apenas quando iniciados o protocolo e a privação para os grupos correspondentes, ocorreu menor ganho de peso semanal nesses grupos em comparação ao Grupo Controle. Com relação ao consumo de alimento, observou-se queda para os três grupos quando iniciada a privação semanal. Iniciado o protocolo de estressores, o consumo de alimento para o Grupo Protocolo apresentou a menor queda dentre os três, comparativamente ao que consumia antes. É sugerido que o consumo de sacarose não é uma boa medida dos efeitos do protocolo, sendo discutidas possibilidades de maior controle sobre essa medida e sugeridas outras medidas como possivelmente mais precisas para aferir os efeitos do protocolo / Chronic Mild Stress (CMS) is an animal model of depression studied by different areas of research into the causes and \"attenuators\" of this problem. In it, rats are subjected to a protocol of moderately aversive stressors applied chronicaly. Decreased intake and preference for sweet liquid substance on behalf of that submission is observed. In a study on the role of the deprivation of food and water in the set of stressors, Pereira and Sério (2010) did not observe the effects of decreased intake and preference for sucrose. It is raised the possibility that the deprivation of food and water that the subjects were submitted previously to the protocol might have been responsible for the differences found, given it differed in many aspects to what was done by Willner et al. (1987). The aim of the present study was to investigate the role of water deprivation in the stress protocol. Three groups of subjects were proposed: Protocol (submitted to the full protocol), Deprivation (subject only to the deprivation of water present in the protocol) and Control (subject only to the weekly consumption and preference tests). Free tests of sucrose intake and preference before, during and after the protocol or the deprivation were carried out. The main results observed were that for both the Protocol and Deprivation Groups and for the Control Group, sucrose consumption decreased over the course of the tests. That means it is not possible to assign to any of the procedures (protocol or deprivation) the decreased consumption observed. Body weight decreased in the three groups as soon as the deprivation procedure preceding the test started, but when the protocol and deprivation for the corresponding groups began, lower weekly weight gain occurred in these groups compared to the control group. With respect to food intake, a decrease for the three groups when initiated weekly deprivation was observed. As the stress protocol began, food intake in this group had the smallest drop compared to that consumed before in relation to the other groups. It is suggested therefore that the sucrose consumption is not a good measure of the effects of the protocol, and possibilities of control over this measure are discussed, along with the suggestion of other more precise measures of the effects of the stress protocol
328

Variação de peso materno e fatores associados em diferentes ambientes intrauterinos

Cazarotto, Bianca da Rosa January 2017 (has links)
Introdução: Diferentes ambientes intrauterinos podem influenciar na variação de peso corporal materno pré-gestacional até seis meses após o parto. A variação de peso é um importante traço materno na direção do ganho de peso gestacional, uma vez que um ganho de peso insuficiente é relacionado ao parto prematuro, ao baixo peso ao nascer ou a um recém-nascido pequeno para a sua idade gestacional, enquanto o seu excesso está associado com o desenvolvimento de diabetes gestacional, parto prematuro, parto cesáreo, recém-nascidos grandes para a sua idade gestacional, retenção de peso materno e, consequentemente, sobrepeso e obesidade. Objetivo: Avaliar a variação do peso materno pré-gestacional até o sexto mês após o parto em puérperas de diferentes ambientes intrauterinos, verificando a associação de fatores sociodemográficos, obstétricos, nutricionais e comportamentais com este desfecho. Métodos: Trata-se de um estudo observacional longitudinal, utilizando uma amostra de conveniência de pares de mães e filhos divididos em quatro grupos: gestantes diabéticas (DM), hipertensas (HAS), tabagistas (TAB) e um grupo controle (CTL). A amostra foi recrutada em três hospitais públicos de Porto Alegre, capital do Rio Grande do Sul, no período de 2011 a 2016. Entrevistas domiciliares e no Centro de Pesquisa Clínica do Hospital de Clínicas de Porto Alegre foram realizadas para a coleta de dados. Foram coletadas informações de peso corporal materno, índice de massa corporal (IMC) pré-gestacional, ingestão alimentar, orientação nutricional durante a gestação e práticas de lactação como variáveis nutricionais-antropométricas; escolaridade materna, etnia, idade, renda familiar e estado civil, como variáveis sociodemográficas; planejamento da gestação, tipo de parto, número de consultas pré-natais e paridade como variáveis obstétricas e percepção de estresse, sintomas depressivos, e nível de atividade física durante a gestação, como variáveis comportamentais. As variáveis nutricionais-antropométricas, sociodemográficas e obstétricas foram coletadas por questionários estruturados. As variáveis comportamentais foram coletadas por meio de instrumentos validados (Escala de Estresse Percebido – 14, Escala de Depressão Pós-Parto de Edimburgo e Questionário Internacional de Atividade Física – versão curta). Regressões lineares múltiplas e modelos de estimativas generalizadas (GLMs) foram conduzidas para a identificação dos fatores associados à variação de peso materno 6 meses após o parto. Todas as análises foram realizadas no programa SPSS, versão 18.0, e o nível de significância adotado para todas as análises foi fixado em 5%, exceto para as comparações aos pares por GLMs, sendo estes em 10%. Resultados: A amostra foi composta de 124 puérperas distribuídas entre diferentes ambientes intrauterinos e um grupo controle. Para todas as GLMs, as medidas de peso materno foram ajustadas para algumas variáveis (estatura materna, paridade, escolaridade materna e tipo de parto), e foram fixadas 3 medições de tempo (peso pré-gestacional, peso antes do parto e 15 dias após o parto) para todas as análises. Os grupos DM e TAB apresentaram maior peso antes do parto, quando comparados com as demais medições. O grupo CTL apresentou maiores pesos 15 dias e 1 mês após o parto, enquanto o grupo HAS apresentou maior peso antes e 15 dias após o parto, em relação às outras avaliações. Um modelo hierárquico associou proximamente o diagnóstico materno de hipertensão arterial e o IMC pré-gestacional de sobrepeso com o ganho de peso materno aferido até o sexto mês após o parto (a diferença entre o peso materno ao sexto mês e o peso pré-gestacional). Já os IMCs pré-gestacionais maternos de desnutrição e de obesidade se associaram com a diminuição de peso corporal seis meses após o parto. Conclusões: Em uma população de diferentes ambientes intrauterinos verificou-se que o IMC de sobrepeso prégestacional e o diagnóstico de hipertensão arterial materna se relacionam com o aumento de peso corporal materno seis meses após o parto. / Introduction: Different intrauterine environments may influence maternal prepregnancy weight variation up to six months after delivery. Gestational weight gain has important maternal-infant repercussions, affecting outcomes of pregnancy and delivery. Insufficient weight gain is related to preterm birth, low birth weight and to newborns small for their gestational age, while its excess is associated with the development of gestational diabetes, preterm delivery, cesarean delivery, newborns large for their gestational age, maternal postpartum weight retention and, consequently, overweight and maternal obesity. Aim: To evaluate the prepregnancy weight gain up to the sixth month after delivery in mothers from different intrauterine environments, verifying its association with sociodemographic, obstetric, nutritional and behavioral factors. Methods: This was a longitudinal observational study, using a convenience sample of mothers and children divided according to four groups of pregnant women: diabetic (DM), hypertensive (HM), smokers (SM), and control (CM) women. The sample was recruited from three public hospitals in Porto Alegre, capital of Rio Grande do Sul, from 2011 to 2016, and the interviews were home conducted or at the Clinical Research Center of the Clinical Hospital of Porto Alegre. Data collection included information on maternal body weight, prepregnancy body mass index (BMI), food intake, nutritional orientation during gestation and lactation practices as nutritionalanthropometric variables; maternal educational level, ethnicity, age, family income and marital status as sociodemographic variables; gestation planning, type of delivery, number of antenatal care visits and parity as obstetric variables; and perceived stress, depressive symptoms, and physical activity level during gestation as behavioral variables. The sociodemographic, nutritional, anthropometric and obstetric variables were collected by structured questionnaires, and the behavioral ones by validated instruments (Perceived Stress Scale – 14, Edinburgh Postpartum Depression Scale, and the International Physical Activity Questionnaire – short version). Multiple linear regressions and Generalized estimates models (GLMs) were conducted to identify factors associated with maternal weight variation up to six months after delivery. The significance level adopted for all analyzes was set at 5%, except for the pairwise comparisons by GLMs, which were set at 10%. All analyzes were performed in the SPSS, version 18.0. Results: The samples consisted of 124 mothers distributed among the four different intrauterine environments. For all GLMs analyzes, maternal weight measures were adjusted for some variables (maternal height, parity, educational level and the type of delivery) and 3 measurements were fixed (prepregnancy, preceding delivery, and 15 days weight after delivery). The DM and SM groups presented greater weight preceding delivery when compared with all other measurements. The CM group displayed higher weights 15 days and 1 month after delivery, while the HM group presented higher weight 15 days after delivery, in relation to other evaluations. A hierarchical model associated maternal diagnosis of hypertension and prepregnancy BMI of overweight with maternal weight gain measured up to the sixth month after delivery (the difference between maternal weight at 6 months and prepregnancy weight). Maternal prepregnancy BMIs of malnutrition and obesity were associated with a decrease in body weight gain six months after childbirth. Conclusions: In a population of different intrauterine environments, it was verified that the prepregnancy overweight BMI and the diagnosis of maternal hypertension were related to maternal body weight gain six months after delivery.
329

Association of Adiponectin Profiles with Dietary Carbohydrate Intake, Feeding, Gender, Body Weight, Fat Mass, and Insulin Sensitivity in Healthy Young Cats (Felis catus)

Heok Yit Tan Unknown Date (has links)
Adiponectin is an adipose-derived protein (adipocytokine) that is secreted by adipose tissue. It has insulin-sensitizing, anti-inflammatory and cardio-protective properties, and is thought to be protective against obesity-related diseases such as type 2 diabetes. Humans and cats are two species that commonly develop type 2 diabetes associated with insulin resistance, impaired beta cell function and spontaneous islet amyloid deposition. The domestic cat (Felis catus) has recently been proposed as an animal model for human type 2 diabetes. However, little is known about the physiology of adiponectin in cats. Therefore, we set out to investigate the association of adiponectin profiles with dietary carbohydrate intake, feeding, body weight, fat mass, and insulin sensitivity in healthy young adult cats (n=32; 2-4 years old; gender ratio 1:1; body condition 4-5/9). Cats were fed a moderate carbohydrate diet (37% ME) at maintenance energy requirements for four weeks. Cats were then assigned to either receive a low (19% ME) or high (52% ME) carbohydrate diet and fed at maintenance energy requirements for another four weeks, followed by ad-libitum feeding for eight weeks to facilitate weight gain. Adiponectin profiles including total circulating adiponectin and its distribution [low molecular weight (LMW) and high molecular weight (HMW) adiponectin], and proportion of adiponectin that is HMW (SA) were measured by ELISA and velocity sedimentation using sucrose gradients, followed by Western blotting, respectively. We demonstrated inter-animal variation in total adiponectin concentration at baseline (0.6 to 15.0 g/mL), with the adiponectin present in both LMW and HMW forms. Feeding with a high carbohydrate diet for four weeks at maintenance energy requirements resulted in increased total adiponectin concentration, which was associated with an increased concentration of LMW adiponectin. In contrast, feeding with a low carbohydrate diet for four weeks at maintenance energy requirements resulted in increased concentration of HMW adiponectin, decreased LMW adiponectin concentration, and increased SA, without a change in total adiponectin concentration. In cats fed the high carbohydrate diet, total adiponectin and HMW adiponectin concentrations become lower at six hours after feeding, as compared to the fasting concentrations. This phenomenon was not observed in cats fed a low carbohydrate diet, indicating a diet-dependent postprandial effect. There was no effect of gender on any of the adiponectin profiles in cats. Unlike other studies in humans and mice in which adiponectin concentrations decreased as fat mass increased, our data indicate that a moderate weight gain achieved by ad libitum feeding of a low carbohydrate diet for eight weeks correlated with increased adiponectin concentrations. Total adiponectin concentration (mirrored by HMW adiponectin) was positively correlated with body weight gain and fat mass gain (but not absolute fat mass) in our overweight cats. Furthermore, the fat mass-related increases in plasma adiponectin over eight weeks correlated with insulin sensitivity (higher adiponectin concentration corresponded to greater insulin sensitivity in overweight cats). These data hint at the possibility that in overweight animals, adiponectin is similar to other adipokines that rise concomitantly with increased of moderate fat mass gain and thus increases insulin sensitivity. Overall, the knowledge in this study therefore provides useful information to veterinarians and cat food manufacturers, and forms a foundation for future studies to extend our knowledge of adiponectin in cats. Data gathered in cats may also be applicable to humans and could therefore inform research using cats as an animal model of human obesity and type 2 diabetes.
330

Geschlechtsspezifische Körpergewichtsregulation bei Mäusen :Untersuchungen zur Set-point-Theorie der Körpermasse

Wiedmer, Petra January 2004 (has links)
Entsprechend der sogenannten Set-point-Theorie besitzt jeder Mensch eine individuell festgelegte Körpermasse, die über große Zeiträume konstant gehalten und gegen Abweichungen verteidigt wird. Es wird angenommen, dass der Körper auf noch unbekannte Weise Änderungen in der Körpermasse per se wahrnimmt und daraufhin Mechanismen aktiviert, die zur Regenerierung der ursprünglichen Masse führen. In dieser Arbeit wurde die Hypothese getestet, dass eine künstliche Erhöhung der Körpermasse zu einer kompensatorischen Reduktion in der Körpermasse führt, um das Ausgangsgewicht wieder zu regenerieren. Die Körpermasse von männlichen und weiblichen Mäusen wurde akut durch die Implantation von Gewichten mit einer Masse von 10% der aktuellen Körpermasse in die Bauchhöhle erhöht. Bei Gültigkeit der Set-point-Theorie sollte die Körpermassereduktion der Masse des zusätzlichen Gewichtsimplantats entsprechen. Die Mäuse reagierten auf die künstlich erhöhte Körpermasse geschlechtsspezifisch. Männchen zeigten eine partielle Reduktion in der Körpermasse. Weibchen zeigten langfristig jedoch keine Änderungen in der Körpermasse. Die Reduktion der Körpermasse erfolgte bei den Männchen durch eine Abnahme in der Fettmasse. Die fettfreie Masse war in beiden Geschlechtern nicht verändert. Änderungen in der Körpermasse wurden vor allem durch Änderungen in der Energieaufnahme hervorgerufen. Ein Einfluss des Energieumsatzes auf Änderungen in der Körpermasse konnte nicht nachgewiesen werden. Die Regulation der Körpermasse entsprechend eines massespezifischen Set-points konnte partiell für die Männchen gezeigt werden. Bei den Männchen könnte daher die Wahrnehmung der Körpermasse in die Regulation der Körpermasse teilweise integriert sein. Weibchen verminderten ihre Körpermasse dagegen trotz der künstlichen Körpermasseerhöhung nicht. Das führte zur Bewahrung der Energiereserven und spricht eher für die Regulation der Körpermasse entsprechend des notwendigen Energiebedarfs im Vergleich zu Änderungen in der Körpermasse per se. Diese Ergebnisse zeigen, dass die Regulation der Körpermasse geschlechtsspezifischen Mechanismen unterliegt. Dementsprechend sind auch geschlechtsspezifische Ansätze zur Therapie von Übergewicht und Adipositas notwendig. / The set-point theory of body mass assumes that humans possess an individually determined body mass which is maintained over long periods and which is defended against deviations. It is supposed that the body can perceive changes in body mass per se, this process leading to activation of mechanisms aiming at regeneration of initial body mass. Here the following hypothesis was tested: An artificial increase in body weight leads to a compensatory reduction in body mass in order to regenerate initial body weight. Body mass of male and female mice was acutely increased by implanting weight loads into the abdominal cavity. Additional weights corresponded to 10% of initial body mass. According to the set-point theory we expected the mice to decrease body mass to the extend of the additional weight. A gender-specific response was observed. Males showed a partially reduced body mass. In contrast, females did not show body mass changes in the long-term. Males reduced their body mass at the expense of fat mass. Fat free mass was unchanged in both genders. Changes in body mass were mainly caused by changes in energy intake. An impact of energy expenditure on body mass changes could not be demonstrated. Body mass regulation according to a mass-specific set-point could be partially shown for males. Therefore, in males perception of body mass could be partially integrated in the regulation of body weight. Females did not decrease their body mass despite artificially increased body mass pointing to preservation of their energy depots. This argues for regulation of body mass according to needed energy requirements rather than according to changes in body mass per se. These results show that body mass regulation underlies gender-specific mechanisms. Accordingly, gender-specific approaches are needed for treating overweight and obesity.

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