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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.
311

Ácido fólico: efeitos paradoxais na promoção da hepatocarcinogênese em ratos / Folic acid: paradoxical effects during promotion of hepatocarcinogenesis in rats.

Bassoli, Bruna Kempfer 18 January 2010 (has links)
A suplementação com ácido fólico (AF) apresenta efeitos quimiopreventivos, porém, pode aumentar o risco de desenvolvimento e acelerar a progressão do câncer se ocorrer em doses elevadas ou após a ocorrência de lesões pré-neoplásicas (LPN). O AF é essencial na síntese de novo de purinas e timidalato e consequentemente na síntese, replicação e reparo do DNA, proliferação celular e apoptose. Assim, a deficiência pode implicar em danos ao DNA e erros na sua replicação e reparo, processos importantes na carcinogênese, onde as células apresentam taxas de replicação e divisão aceleradas, e é possível que a suplementação module estes processos. Além disso, como AF ocupa uma posição de destaque no metabolismo dos grupamentos metila pode exercer efeitos sobre a hipometilação global do DNA e o aumento da expressão de proto-oncogenes como o c-myc, fenômenos característicos da hepatocarcinogênese. Assim, objetivando-se avaliar os efeitos do AF na promoção da hepatocarcinogênese em ratos Wistar, desenvolveu-se o modelo do \"Hepatócito Resistente\" e administrou-se por entubação gástrica diariamente, durante 5 semanas, o AF (0,16; 0,32; ou 0,64 mg / 100 g de peso / dia) ou água (0,25 mL / 100 g de peso / dia). Então, avaliou-se as LPN hepáticas presentes visíveis à macroscopia e microscopia (GST-P), a proliferação celular (BrdU) e a apoptose (microscopia de fluorescência) no tecido hepático ao redor das LPN e nas LPN persistentes e em remodelação, a intensidade de danos ao DNA (\"Cometa\" alcalino), e o padrão de metilação global (Dot Blot) e a expressão do c-myc (RT-PCR) especificamente em LPN microdissecadas. Apesar de não ter alterado a incidência e multiplicidade das LPN, o tratamento com AF 0,32 mg / 100 g promoveu um aumento na porcentagem de lesões &#8805; 1 mm e o com AF 0,64 mg / 100 g a diminuição na porcentagem dessa lesões com relação ao grupo água (p<0,05). De modo semelhante, observou-se na análise das LPN GST-P positivas que o AF 0,32 mg / 100 g promoveu aumento e o AF 0,64 mg / 100 g inibiu o processo carcinogênico, embora não se tenha observado diferenças significantes no número, área e porcentagem da área do corte ocupada pelas LPN. Apesar de não ter modulado significativamente o desenvolvimento das LPN, o AF nas doses de 0,32 e 0,64 mg / 100 g inibiu a proliferação celular nas LPN persistentes (p<0,05). A contagem dos corpúsculos apoptóticos permitiu constatar uma possível inibição da apoptose nas LPN persistentes e em remodelação com caráter dose-dependente (p>0,05). De acordo com a análise do comprimento dos cometas, houve um aumento dos danos ao DNA no modelo de hepatocarcinogênese e ausência de efeito do AF nesse processo (p>0,05). O padrão de metilação global do DNA e a expressão do c-myc nas LPN microdissecadas não foram significativamente alterados pelo tratamento com diferentes doses de AF, embora, em geral, se tenha observado uma tendência dos tratamentos com AF promoverem hipometilação e aumento da expressão de c-myc. Os resultados obtidos, em conjunto, auxiliaram na caracterização das ações paradoxais (inibitórias e promotoras) que o AF apresenta na etapa de promoção da carcinogênese, de forma que a dose e o estágio do desenvolvimento neoplásico em que se inicia a suplementação demonstraram ser críticos e, por isso, indicam necessidade de cautela acerca da fortificação com o AF, uma das maiores intervenções de saúde pública que expôs a população a elevadas concentrações de AF sintético. / Folic acid (FA) supplementation shows chemopreventive effects, however, it may increase the risk of development and accelerate cancer progression in case of high doses or after preneoplastic lesions (PNL) are established. FA is essential on de novo synthesis of purine and thymidalate and, consequently, on DNA synthesis, replication and repair, cell proliferation and apoptosis. Thus, its deficiency may cause DNA damage and replication and repair mistakes, important processes on carcinogenesis, where cells present high replication rates and accelerated division, and is possible that supplementation modulates these processes. Besides, as FA has a central role on methyl group metabolism, it may have effects on hepatocarcinogenesis peculiar events such as DNA global hypomethylation and on the increased expression of proto-oncogenes like c-myc. Objecting the evaluation of FA effects during hepatocarcinogenesis promotion in Wistar rats, the \"Resistant Hepatocyte\" model was developed and water (0.25 mL / 100 g BW / day) or FA (0.16; 0.32; or 0.64 mg / 100 g BW / day) were supplemented daily by gavage for 5 weeks. Then, hepatic PNL detected by macroscopy and microscopy (GST-P), cell proliferation (BrdU) and apoptosis (fluorescence microscopy) on surrounding tissue, persistent and remodeling PNL, DNA damage (alcaline Comet assay), DNA global methylation pattern (Dot Blot) and c-myc expression (RT-PCR) specifically in microdissected PNL were evaluated. Even though FA treatment was not able to change incidence and multiplicity of PNL, the treatment with 0.32 mg / 100 g of FA increased the percentage of lesions &#8805; 1 mm whereas with 0.64 mg / 100 g of FA diminished the percentage of these lesions, compaired to the water group (p<0.05). Similarly, it could be observed in PNL positive GST-P analysis that FA 0.32 mg / 100 g enhanced and FA 0.64 mg / 100 g inhibited the carcinogenic process, although it was not possible to detect significant differences on number, size and area of liver section occupied by GST-P positive PNL. Despite the fact that PNL development was not significantly modulated by FA, FA 0.32 and 0.64 mg / 100 g dosages inhibited cell proliferation on persistent PNL (p<0.05). The apoptotic body count allowed to identify a possible dosage-dependent apoptosis inhibition on persistent and remodeling PNL (p>0.05). According to the analysis of comet length, the hepatocarcinogenesis model increased DNA damage but FA showed lack of effect on this process (p>0.05). DNA global methylation pattern and c-myc expression in microdissected PNL were not significantly altered by treatment with different dosages of FA, although a trend towards promotion of hypomethylation and increase on c-myc expression was observed. Altogether, the obtained results helped to characterize the paradoxical action (both inhibitory and promoting) that FA has on carcinogenesis promotion step, in such a way that the dosage and the stage of neoplastic development in which supplementation begins seems to be critical, highlighting the necessity of caution with FA fortification, one of the biggest public health interventions taken that exposes the population to high concentrations of synthetic FA.
312

Didrogesterona versus progesterona como suporte de fase lútea: revisão sistematizada e meta-análise de ensaios clínicos randomizados / Dydrogesterone versus progesterone for luteal-phase support: systematic review and meta-analysis of randomized controlled trials

Barbosa, Marina Wanderley Paes 16 August 2017 (has links)
Justificativa: Há evidências de que o uso de progesterona para suporte de fase lútea melhora os resultados reprodutivos em mulheres submetidas a técnicas de reprodução assistida (TRA). Há várias hipóteses para justificar a deficiência de fase lútea após a estimulação ovariana controlada (EOC) para TRA. Atualmente, acredita-se que os níveis supra-fisiológicos de esteroides alcançados durante a EOC persistem após a aspiração folicular, graças à formação de múltiplos corpos lúteos. Dessa forma, ocorre um feedback negativo prematuro na secreção de hormônio luteinizante (LH), causando um defeito da fase lútea e baixos níveis de progesterona. A progesterona natural por via intramuscular ou vaginal apresenta efeitos comparáveis sobre os parâmetros de gravidez clínica e gravidez em curso, embora as pacientes possam apresentar vários efeitos colaterais, como dor e abscesso local com a progesterona intramuscular, e corrimento vaginal, irritação perineal e interferência com o coito com a progesterona vaginal. Desta forma, a didrogesterona, uma progesterona sintética com boa biodisponibilidade oral, vem sendo estudada como uma alternativa para suporte de fase lútea em mulheres submetidas à TRA. Objetivo: Comparar a didrogesterona oral com a progesterona vaginal como suporte de fase lútea em ciclos de reprodução assistida. Métodos de busca: As buscas por ensaios clínicos randomizados (ECRs) foram realizadas nos principais bancos eletrônicos de dados; além disso, examinamos manualmente as listas de referências dos estudos incluídos em revisões semelhantes. A última busca eletrônica foi feita em 18 de outubro de 2015. Critérios de Seleção: Apenas estudos verdadeiramente randomizados que comparassem o uso da didrogesterona com a progesterona como suporte de fase lútea foram considerados elegíveis. Os estudos que permitiam a inclusão de uma mesma paciente duas vezes foram incluídos apenas se os dados do primeiro ciclo estivessem disponíveis. Coleta e Análise de Dados: Dois revisores avaliaram, independentemente, a elegibilidade dos estudos, extração de dados e os riscos de vieses dos estudos incluídos. Quaisquer discordâncias foram resolvidas por consenso. Quando necessário, os autores dos estudos incluídos foram contatados para maiores informações. Resultados: A busca selecionou 343 registros, 8 dos quais eram elegíveis. Nenhum estudo relatou nascidos vivos. Não há diferença relevante entre didrogesterona oral e progesterona vaginal para gravidez em curso, (RR 1.04, IC 95% 0.92 a 1.18, I² = 0%, p = 0.53, 7 ECRs, 3,134 mulheres), gravidez clínica (RR 1.07, IC 95% 0.93 a 1.23, I² = 34%, p = 0.35, 8 ECRs, 3,809 mulheres), e para abortamento (RR 0.77, IC 95% 0.53 a 1.10, I² = 0%, p = 0.15, 7 ECRs, 906 gestações clínicas). Três estudos reportaram o grau de insatisfação com o tratamento. Dois deles mostraram uma redução importante na insatisfação entre as mulheres que utilizaram didrogesterona em comparação com a progesterona vaginal: didrogesterona oral = 2/79 (2.5%) vs. progesterona vaginal em cápsulas = 90/351 (25.6%), e didrogesterona oral = 19/411 (4.6%) vs. progesterona vaginal em gel = 74/411 (18.0%); o outro estudo não mostrou diferença na taxa de insatisfação: didrogesterona oral = 8/96 (8.3%) vs. progesterona vaginal em cápsulas = 8/114 (7.0%). Conclusão: As evidências atuais sugerem que o uso de didrogesterona oral é tão eficaz quanto a progesterona vaginal como suporte de fase lútea em ciclos de reprodução assistida. Em relação ao grau de satisfação com o tratamento, a didrogesterona oral parece causar menos insatisfação entre as pacientes, em comparação ao uso de progesterona vaginal. / Background: There is evidence that using progesterone for LPS improves the reproductive outcomes in women undergoing ART. There are several hypotheses to justify the lutheal phase deficiency (LPD) after controlled ovarian stimulation (COS) for ART. Currently, it is believed that the supra-physiological levels of steroids achieved during COS and sustained after oocyte aspiration by the multiple corpora lutea causes a prematurely negative feedback in pituitary LH secretion, consequently causing a luteal phase defect and low progesterone levels. Both intramuscular and vaginal routes of natural progesterone exhibit comparable effect on the endpoints of clinical pregnancy and ongoing pregnancy, although patients may exhibit multiple side effects, such as pain and local abscess with intramuscular progesterone, and vaginal discharge, perineal irritation and interference with coitus with vaginal progesterone. In this way, dydrogesterone, a synthetic progesterone with good oral availability, has being studied as an alternative for LPS in women undergoing ART. Objectives: To compare dydrogesterone and progesterone for luteal-phase support in women undergoing assisted reproduction technique. Search methods: The searches for randomized controlled trials (RCT) were performed in the main electronic databases; in addition, we handsearched the reference lists of included studies and similar reviews. We performed the last electronic search on October 18, 2015. Selection criteria: Only truly randomized controlled trials comparing oral dydrogesterone to vaginal progesterone as luteal phase support were considered eligible. We included studies that permitted the inclusion of the same participant more than once (cross-over or \'per cycle\' trials) only if data regarding the first treatment of each participant were available. Data collection and analysis: Two reviewers independently performed study eligibility, data extraction, and assessment of the risk of bias and we solved disagreements by consensus. We corresponded with study investigators in order to resolve any queries, as required. Results: The search retrieved 353 records; eight studies were eligible. No study reported live birth. There is evidence of no relevant difference between oral dydrogesterone and vaginal progesterone on ongoing pregnancy (RR 1.04, 95% CI 0.92 to 1.18, I² = 0%, 7 RCTs, 3,134 women), on clinical pregnancy (RR 1.07, 95% CI 0.93 to 1.23, I² = 34%, 8 RCTs, 3,809 women), and on miscarriage (RR 0.77, 95% CI 0.53 to 1.10, I² = 0%, 7 RCTs, 906 clinical pregnancies). Three studies reported dissatisfaction rate with the treatment. Two of them reported a large reduction in dissatisfaction among women using oral dydrogesterone than among women using vaginal progesterone: oral dydrogesterone = 2/79 (2.5%) vs. vaginal progesterone capsules = 90/351 (25.6%), and oral dydrogesterone = 19/411 (4.6%) vs. vaginal progesterone gel = 74/411 (18.0%). The other included study showed no difference in the dissatisfaction rate: oral dydrogesterone = 8/96 (8.3%) vs. vaginal progesterone capsules = 8/114 (7.0%). Authors\' conclusions: Oral dydrogesterone is as effective as vaginal progesterone for luteal-phase supplementation in ART cycles. Regarding dissatisfaction with treatment, oral dydrogesterone seems to cause less dissatisfaction among patients, in comparison to vaginal progesterone.
313

Factors Impacting Bone Mineral Density (BMD) Results of Individuals with Intellectual and Developmental Disabilities (IDD)

McNabb, Rhonda 01 May 2018 (has links)
Individuals with intellectual and developmental disabilities (IDD) are prone to certain diseases in their lifetime, such as osteoporosis. Absorption of calcium is essential to maintaining good bone health and preventing osteoporosis. This study examined primary care providers’ (PCPs) choice of calcium supplementation, as well as type of calcium supplementation, and the relationship between variables in the IDD population. Ten PCPs were asked to complete a 14-question web-based survey, with five surveys completed. Calcium citrate was the preferred supplement among respondents at 50%. Retrospective data was collected from patient records and included type of calcium supplement prescribed, bone density test results, and other variable factors. The type of calcium supplement prescribed did not affect bone density results in subjects with IDD. There was a weak significance between calcium supplement type and gender and vitamin D. It is of modest benefit to include vitamin D with calcium supplementation to enhance calcium absorption.
314

Effect of time of initiation of feeding after hatching and influence of dietary lysine and ascorbic acid supplementation on productivity and mortality of Ross 308 broiler chickens

Mbajiorgu, Christian A. January 2007 (has links)
Thesis (M.Sc. (Animal Production)) --University of Limpopo, 2007 / Two experiments were conducted to evaluate the effect of time of initiation of feeding after hatching and influence of dietary lysine and ascorbic acid supplementation on productivity, carcass characteristics and mortality of Ross 308 broiler chickens. The first experiment examined the effect of time of initiation of feeding after hatching and influence of dietary lysine supplementation during realimentation on productivity, carcass characteristics and mortality of Ross 308 broiler chickens during the winter period. Three hundred and sixty unsexed Ross 308 broiler chickens with an initial weight of 30 ± 2 g per bird were assigned to twelve treatments with three replications of ten birds each in a 4 (times of initiation of feeding) x 3 (lysine supplemental levels) factorial, complete randomized design. At each time of initiation of feeding after hatching during the starter and grower stages, the diets were isocaloric and isonitrogenous but with three different lysine supplementation levels. Lysine supplementation started three days after hatching. Time of initiation of feeding above 36 hours after hatching resulted in growth retardation and high mortality rate. More than 50 % of the birds died between one and three days of age when initiation of feeding after hatching was above 36 hours. However, the birds ‘caught-up’ at the latest within eight days of realimentation. This compensatory growth could be explained in terms of higher intakes. Lysine supplementation during realimentation reduced the number of days of ‘catch-up’ irrespective of time of initiation of feeding after hatching. Generally, the higher the level of lysine supplementation, the lower was the number of days of ‘catch-up’ upon realimentation. Thereafter, time of initiation of feeding after hatching and lysine supplementation had no effect (P>0.05) on live weight, feed intake, growth rate, feed conversion ratio, diet digestibility, nitrogen content of breast meat, dressing %, carcass characteristics and mortality of Ross 308 broiler chickens. The second experiment examined the effect of time of initiation of feeding after hatching and influence of dietary ascorbic acid supplementation on productivity, carcass characteristics and mortality of Ross 308 broiler chickens during the summer period. Six v hundred and seventy five unsexed Ross 308 broiler chickens with an initial weight of 32 ± 2 g per bird were assigned to fifteen treatments with three replications of fifteen birds each in a 3 (times of initiation of feeding) x 5 (ascorbic acid supplemental levels) factorial, complete randomized design. Ascorbic acid supplementation started 3 days after hatching. An average of 18 % and 31 % of the birds died between one and three days of age when initiation of feeding after hatching was above 36 hours. However, the birds ‘caught-up’ within ten days of realimentation irrespective of time of initiation of feeding after hatching. This compensatory growth could be explained in terms of reduced maintenance requirement and possibly, increased efficiency of growth. Following ‘catch-up’, ascorbic acid supplementation during realimentation lowered (P<0.05) mortality rate and improved growth rates irrespective of time of initiation of feeding after hatching. Growth rate increased incrementally with increasing levels of ascorbic acid supplementation within each time of initiation of feeding after hatching. Improved growth rate in the ascorbic acid supplemented birds resulted in improved live weight in comparison with those without ascorbic acid supplementation at 21 days of age and continued until 42 days of age. Live weight increased incrementally with increasing levels of ascorbic acid supplementation within each time of initiation of feeding after hatching. Similarly, increasing ascorbic acid supplementation within each time of initiation of feeding after hatching increased dressing percentage and breast meat yield at 42 days old. However, ascorbic acid supplementation had no effect (P>0.05) on feed intake of the birds irrespective of time of initiation of feeding after hatching. In both experiments, mortality was positively and strongly correlated with time of initiation of feeding after hatching while live weight was negatively and strongly correlated with time of initiation of feeding after hatching. It is concluded that time of initiation of feeding above 36 hours after hatching is not desirable, mainly because of its effect on mortality. However, lysine supplementation in the diet of broiler chickens subjected to delayed initiation of feeding after hatching might play a key role in accelerating the rate of ‘catch-up’ growth response. vi It is also concluded that the beneficial effect of ascorbic acid supplementation could be exploited in reducing mortality rate and improving growth rates in broiler chickens subjected to delayed initiation of feeding after hatching. / the National Research Foundation
315

Development of an experimental approach to measure vitamin B12 production and absorption in sheep

Ludemann, M. R. January 2009 (has links)
Clinical diagnosis of vitamin B12/cobalt (Co) deficiency is difficult due to the unspecific nature of the clinical symptoms. The apparent increase in vitamin B12 deficiency in New Zealand in the late 1990’s made it clear that health providers were very reliant on plasma reference ranges to diagnose deficiency. However, the lack of quantitative data of what these reference ranges represent in terms of supply of vitamin B12, has prevented a better understanding of the metabolism of vitamin B12 within sheep. This thesis describes the development of an experimental approach to measure vitamin B12 production and absorption in sheep. The model was then used to investigate whether the type of carbohydrate source affects vitamin B12 production and/or absorption. In the first trial (Chapter 4), an adaptation of the repletion technique of Suttle (1974) for copper was used. Previously vitamin B12 depleted sheep were maintained on a diet of 400 g DM meadow hay and 250 g DM crushed barley and which provided a daily intake of 0.03 mg Co. Sheep were intravenously infused with known quantities of vitamin B12 (0 – 200 nmol hydroxycobalamin/d) to determine whether a relationship exists between plasma vitamin B12 concentration and rate of entry of the vitamin into the bloodstream and to quantify the relationship. Eight ewes fitted with rumen and abomasal cannulae were used in a paired 4x4 Latin square design. Four levels of vitamin B12 were infused into the jugular vein for 4 d followed by recovery period of 17 d and the plasma responses measured during this period. Control animals maintained relatively stable plasma levels while levels in treated animals rose sharply within 4 h after the start of infusion. The responses were proportional to infusion rate with a highly significant difference in concentrations observed between treatments (P<0.001). Appearance of vitamin B12 in the plasma was quantified by the relationship Y(pmol/l) = 238 + 102x0.74 where x = infusion rate(nmol B12/d), R² = 0.945. Plasma levels declined rapidly on cessation of infusion and had returned to original pre-treatment levels by the end of the recovery period. The second trial (Chapter 5) quantified plasma responses in relation to dietary Co supply to the rumen. The same eight rumen and abomasal cannulated ewes were used in a paired 4x4 Latin square with 4 levels of intra-ruminal Co infusion in amounts ranging from 0 – 1 mg Co/d as CoSO₄, infused for 4 d followed by a 19 d recovery period. Plasma vitamin B12 response was measured as were concentration of vitamin B12 in abomasal digesta supernatant and digesta liquid flow, the latter using polyethylene glycol as liquid phase marker. Plasma concentration increased from approximately 300 pmol/l to 750 – 800 pmol/l, peaking at day 5 after commencement of infusions. Control animals infused with water maintained base-line plasma vitamin B12 levels around 250 pmol/l. Digesta liquid flow was estimated at 14.6 l/d. The results from Chapters 4 and 5 allowed estimates of vitamin B12 production and absorption. These results are discussed and efficiency of capture of Co into vitamin B12 from dietary Co intake was estimated to decrease from 8.4% to 0.74% as Co intake increased from 0.03 to 1.11 mg Co/d. Absorption coefficient was estimated from the relationships between abomasal vitamin B12 flow and plasma response. The absorption coefficient was calculated to increase from 7 to 10% as abomasal vitamin B12 flow increased from 108 to 142 nmol/d. The current animal model was subsequently used in the final trial (Chapter 6) to investigate whether the type of carbohydrate supplied in the diet influences vitamin B12 production and absorption. The same eight ewes fitted with rumen and abomasal cannulae were used in a 2x4 cross-over design. Half of the ewes were maintained on the basal diet and crushed barley while, for the remainder, the barley was replaced by 250 g of fructose:sucrose in a 80:20 mix during a 7 d period of adaptation. While on their respective diets, both groups were then infused with 0.3 mg Co/d for 6 d, a level chosen to optimise plasma vitamin B12 response. All ewes were then returned to the basal diet and barley for a 15 d recovery period after which treatments were reversed and the procedure repeated. Rumen pH, valeric, propionic, butyric, succinic, and acetic acid and ammonia concentrations were not significantly affected by diet. Digesta flow was 30% greater on a diet enriched with starch compared to sugar-enriched diet. There was an observed difference in vitamin B12 production. However there was no significant diet x time effect on plasma vitamin B12 concentration so any difference in production was negated by a difference in absorption. Carbohydrate supplied as water soluble carbohydrate or starch does not appear to influence plasma vitamin B12 concentration.
316

Omega-3 Fatty Acid Blood Biomarkers Before and After Acute Fish Oil Supplementation in Men and Women

Metherel, Adam Henry January 2007 (has links)
Omega-3 fatty acids, particularly docosahexaenoic (DHA) and eicospentaenoic acid (EPA), are important mediators for cardiovascular disease, fetal/infant development, neurological disorders and inflammatory diseases. Supplementation and washout studies are important for future research on the physiological effects of omega-3 fatty acids and for determination of the proper washout period for future cross-over studies. In this study, omega-3 fatty acid blood biomarker comparisons are made for the n-3 HUFA score (% of n-3 HUFAs in total HUFAs) and omega-3 index (sum of EPA + DHA) in plasma, erythrocytes, whole blood and a novel finger-tip prick blood method (FTPB) of analysis. This FTPB method of fatty acid analysis is further tested to determine the potential for its use in fatty acid analysis. In addition, gender differences in response to omega-3 fish oil supplementation are analyzed in all four blood fractions. Nine males and seven females were supplemented with 8 fish-oil capsules per day (providing 3.2 g/day EPA and 1.6 g/day DHA) for four weeks, followed by an eight-week omega-3 washout period. Venous plasma, erythrocyte and whole blood samples were collected during weeks 0, 4, 8 and 12 and FTPB samples were collected weekly during supplementation and washout fatty acid analysis was performed. EPA and DHA incorporation is lowest in magnitude in erythrocytes relative to all other blood fractions. Omega-3 blood biomarker comparisons demonstrate that the n-3 HUFA score is a more reliable measure across all blood fractions compared to the omega-3 index. In addition, the n-3 HUFA score demonstrates no differences (p > 0.05) between FTPB and whole blood analysis, providing evidence to support its usefulness as a tool for fatty acid analysis. However, differences (p < 0.05) do exist between these methods for saturated fatty acid, monounsaturated fatty acids, omega-6 polyunsaturated fatty acids (PUFAs) and omega-3 PUFAs. Baseline fatty acid levels for DHA, and the DHA:EPA and DHA:DPA ratios tend to be higher (p < 0.05) in females, and docosapentaenoic acid n-3 (DPAn-3) is higher (p > 0.05) in males across all blood fractions. Furthermore, a gender effect (p < 0.05) is seen for the DHA:EPA ratio across all blood fractions. At baseline, female DHA:EPA is higher (p < 0.05) than males with supplementation lowering both male and female values and removing any differences (p > 0.05) between genders. Washout results in a return of levels towards baseline, however, baseline levels are not fully reached. Furthermore, while gender differences do begin to reform during washout, these differences are not significant (p > 0.05). In conclusion, omega-3 fatty acid responses, particularly DHA:EPA ratio, demonstrate significant gender differences that may be related to differences in long-chain PUFA synthesis pathways between males and females. In addition, the n-3 HUFA score may be a more valuable omega-3 blood biomarker than the omega-3 index, as the n-3 HUFA score displays more consistent levels across all blood fractions. Finally, the FTPB method of analysis may be a useful tool in the measurement of fatty acid composition, however, some microwave methylation problems do exist, specifically in the phospholipid class of lipids.
317

Omega-3 Fatty Acid Blood Biomarkers Before and After Acute Fish Oil Supplementation in Men and Women

Metherel, Adam Henry January 2007 (has links)
Omega-3 fatty acids, particularly docosahexaenoic (DHA) and eicospentaenoic acid (EPA), are important mediators for cardiovascular disease, fetal/infant development, neurological disorders and inflammatory diseases. Supplementation and washout studies are important for future research on the physiological effects of omega-3 fatty acids and for determination of the proper washout period for future cross-over studies. In this study, omega-3 fatty acid blood biomarker comparisons are made for the n-3 HUFA score (% of n-3 HUFAs in total HUFAs) and omega-3 index (sum of EPA + DHA) in plasma, erythrocytes, whole blood and a novel finger-tip prick blood method (FTPB) of analysis. This FTPB method of fatty acid analysis is further tested to determine the potential for its use in fatty acid analysis. In addition, gender differences in response to omega-3 fish oil supplementation are analyzed in all four blood fractions. Nine males and seven females were supplemented with 8 fish-oil capsules per day (providing 3.2 g/day EPA and 1.6 g/day DHA) for four weeks, followed by an eight-week omega-3 washout period. Venous plasma, erythrocyte and whole blood samples were collected during weeks 0, 4, 8 and 12 and FTPB samples were collected weekly during supplementation and washout fatty acid analysis was performed. EPA and DHA incorporation is lowest in magnitude in erythrocytes relative to all other blood fractions. Omega-3 blood biomarker comparisons demonstrate that the n-3 HUFA score is a more reliable measure across all blood fractions compared to the omega-3 index. In addition, the n-3 HUFA score demonstrates no differences (p > 0.05) between FTPB and whole blood analysis, providing evidence to support its usefulness as a tool for fatty acid analysis. However, differences (p < 0.05) do exist between these methods for saturated fatty acid, monounsaturated fatty acids, omega-6 polyunsaturated fatty acids (PUFAs) and omega-3 PUFAs. Baseline fatty acid levels for DHA, and the DHA:EPA and DHA:DPA ratios tend to be higher (p < 0.05) in females, and docosapentaenoic acid n-3 (DPAn-3) is higher (p > 0.05) in males across all blood fractions. Furthermore, a gender effect (p < 0.05) is seen for the DHA:EPA ratio across all blood fractions. At baseline, female DHA:EPA is higher (p < 0.05) than males with supplementation lowering both male and female values and removing any differences (p > 0.05) between genders. Washout results in a return of levels towards baseline, however, baseline levels are not fully reached. Furthermore, while gender differences do begin to reform during washout, these differences are not significant (p > 0.05). In conclusion, omega-3 fatty acid responses, particularly DHA:EPA ratio, demonstrate significant gender differences that may be related to differences in long-chain PUFA synthesis pathways between males and females. In addition, the n-3 HUFA score may be a more valuable omega-3 blood biomarker than the omega-3 index, as the n-3 HUFA score displays more consistent levels across all blood fractions. Finally, the FTPB method of analysis may be a useful tool in the measurement of fatty acid composition, however, some microwave methylation problems do exist, specifically in the phospholipid class of lipids.
318

Metadata_photography and the construction of meaning : a thesis presented in partial fulfilment of the requirements for the degree Master of Fine Arts to Massey University, College of Creative Arts, School of Fine Arts, Wellington, New Zealand

Nishioka, Mizuho January 2010 (has links)
Photographic technology is increasingly respondent to a desire for the production and consumption of information. The current age of photography not only possesses the ability to capture the image, but also to capture photographic metadata as supplemental information. Engaging in the premise that the photographic image exists as an incomplete medium to the transfer of information, this research identifies the acquisition of data as a means to resolve interpretation and quantify the photographic image. Inhabiting a complex territory within this structure, the photographic image manifests multiplicity and operates as source, production, and capture of information. This work challenges the perceptions of how to engage with the dialogues created between the photographic image, and the externally appended metadata.
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Evaluation of the implementation of the nutritional supplementation programmes for pregnant women within the Cape Town Metropolitan Area

Grundlingh, Heila 12 1900 (has links)
Thesis (MNutrition )ITE))--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Introduction: The primary objective was to determine whether pregnant women visiting primary health care clinics (PHCs) were aware of the nutritional supplementation programmes: Nutrition Supplementation Programme (NSP) food, folate-, iron- and vitamin A supplementation. The secondary objective was to determine whether pregnant women qualified for the NSP food-, folate- and iron supplementation. The third objective was to determine whether those who qualified received the prescribed NSP food-, folate-, and iron supplementation and whether they were compliant with these interventions. Design: A cross-sectional descriptive study was conducted at all PHCs hosting basic antenatal clinics in the Cape Town Metropolitan Area of the Western Cape Province, South Africa. Method: One hundred and fourteen pregnant women who met the inclusion criteria were included in the study using a non-random quota sampling strategy. Pregnant women were interviewed using a validated questionnaire. The mid upper arm circumference (MUAC) was measured and the symphysis-fundus (SF) measurement was obtained from the medical files to determine whether participants met the entry criteria for the NSP. Written informed consent was obtained from participants. Results: Fifty per cent of participants were between 12 and 24 weeks of gestation. Most of them (68%) had an MUAC of between 24,7 cm and 34,4 cm. Fifty (44%) of the participants had a sufficient SF measurement. Twenty-one (18%) of the participants indicated that they were aware of the vitamin A Programme, 56 (49%) were aware of the NSP food-supplementation and 79 (70%) knew about the folicand iron supplementation that pregnant women should receive from the clinic. Six (5%) participants qualified for the NSP with an MUAC of below 23 cm. Only one (17%) participant was registered with the NSP and received the food-supplementation. Seventy (61%) of the participants indicated that they received and used the iron- and folic supplements, of which 30 (43%) did not know why they needed to take these supplements. Conclusion: Folate- and iron supplementation appears to be reasonably successfully implemented in the Cape Town Metropolitan Area among pregnant women visiting PHCs. The NSP food-supplementation, however, appears to be unsuccessfully implemented and needs further attention. Resources could be appointed to inform pregnant women about the reasons for and importance of taking these supplements. / AFRIKAANSE OPSOMMING: Inleiding: Die hoofdoelstelling was om te bepaal of swanger vroue wat primêre gesondheidsorgklinieke (PGK’s) bywoon, bewus was van die voeding supplementasie programme: Voedsel Supplementasie Program (VSP) – voedselaanvulling, folaat-, yster- en vitamien A supplementasie. Die tweede doelstelling was om te bepaal of hierdie swanger vroue in aanmerking kom vir die VSP– voedselaanvulling, folaat- en yster supplementasie. Die derde doelstelling was om te bepaal of hierdie swanger vroue die voorgeskrewe VSP – voedselaanvulling, folaat- en yster supplementasie ontvang het en hierdie intervensies nagevolg het. Ontwerp: ʼn Deursnit beskrywende studie is gedoen en data is ingesamel van al die PGK’s wat voorgeboortelike klinieke huisves in die Kaapstadse metropolitaanse gebied, in die Wes-Kaapprovinsie, Suid-Afrika. Metode: Honderd en veertien swanger vroue wat aan die insluitingskriteria voldoen het, is volgens ʼn nie-ewekansige kwotastrategie uitgesoek om aan die studie deel te neem. Onderhoude is volgens ʼn bevestigde vraelys met swanger vroue gevoer. Die omtrek van die middelboarm is geneem en die symphysis-fundus-meting is van die mediese lêers verkry om te bepaal of deelnemers aan die insluitingskriteria vir die VSP voldoen. Deelnemers het ʼn vrywaringsvorm geteken voordat hulle aan die studie begin deelneem het. Resultate: Vyftig persent van die swanger vroue het ʼn gestasie-ouderdom van tussen 12 en 24 weke gehad. Die omtrek van die meeste vroue (68%) se middelboarm was tussen 24,7 cm en 34,4 cm. Vyftig (44%) van die vroue se symphysis-fundusmeting was voldoende. Een en twintig (18%) van die deelnemers het aangedui dat hulle van die Vitamien A-program bewus was, 56 (49%) was van die VSPvoedselaanvulling bewus en 79 (70%) van die deelnemers was bewus van die folaat- en yster supplementasie wat swanger vroue van die kliniek behoort te ontvang. Ses (5%) deelnemers, met ʼn middelboarm-omtrek van minder as 23 cm, het vir die VSP in aanmerking gekom. Slegs een (17%) deelnemer was geregistreer en het die voedselaanvulling ontvang. Sewentig (61%) van die deelnemers het aangedui dat hul wel yster- en folaat supplementasie ontvang en gebruik, waarvan 30 (43%) nie geweet het waarom hulle dié supplemente neem nie. Gevolgtrekking: Dit wil voorkom asof folaat- en yster supplementasie vir swanger vroue wat PGK’s in die Kaapstadse metropolitaanse gebied besoek, redelik suksesvol toegepas word. Daarteenoor word die VSP – voedselaanvulling onsuksesvol uitgevoer en behoort dit verdere aandag te geniet. Hulpbronne kan aangewys word om swanger vroue beter in te lig oor die doel en belangrikheid daarvan om hierdie supplemente te neem.
320

Avaliação de dietas lipídicas fornecidas em duas frequências de suplementação na terminação de novilhas em pastejo /

Santana, Márcia Cristina Araújo. January 2010 (has links)
Resumo: Objetivou-se avaliar o efeito de suplementos lipídicos disponíveis em diferentes formas (soja em grão moído, óleo de soja, e sais de cálcio - SC) no consumo de matéria seca total; comportamento ingestivo; desempenho corporal; parâmetros de fermentação ruminal; características de carcaça; desenvolvimento e composição corporal; e na qualidade da carne de novilhas mantidas em pastagens de Brachiaria brizantha cv. Marandu suplementadas em duas frequências (diária ou segunda, quarta e sexta - SQS). O experimento foi realizado nos meses de julho a novembro de 2007. Foram utilizadas novilhas mestiças (1/4 Nelore x 1/4 Santa Gertrudis x 1/2 Braunvieh), alimentadas com três suplementos lipídicos na quantidade de 0,75% do peso corporal. Os dados foram analisados em delineamento inteiramente casualisados com os tratamentos em arranjo fatorial (3x2 - três suplementos lipídicos e duas frequências alimentares). O consumo de matéria seca total foi maior nos meses de agosto e outubro em relação ao mês novembro. Houve efeito das formas de fornecimento da fonte lipídica sobre o consumo em kg de matéria seca total, forragem e nutrientes. Durante o período seco e início das águas os animais obtiveram ganhos médios totais de 0,577g dia-1, que não foram influenciados pelas suplementos lipídicos e frequências de suplementação utilizadas. A redução na frequência de suplementação alterou o tempo de pastejo em função dos suplementos lipídicos. Não houve influência dos suplementos lipídicos e das frequências de suplementação sobre o balanço de compostos nitrogenados, na síntese e eficiência de proteína microbiana. Houve influência das formas de fornecimento dos suplementos lipídicos sobre os valores de pH ruminal. A menor frequência de suplementação proporcionou diferenças nas concentrações de nitrogênio amoniacal ruminal... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This research aimed to evaluate total dry matter intake, feeding behavior, growth performance, rumen fermentation parameters; carcass characteristics, development and body composition, and meat quality responses of steers grazing Brachiaria brizantha cv. Marandu supplemented at two frequencies (daily or Monday, Wednesday and Friday - MWF), under different forms of lipid supplements (soybean grain, soybean oil, and calcium salts - CS). This research was conducted throughout a four month period during the dry season (July to November 2007). Crossbred heifers were used (1/4 Nellore x 1/4 Santa Gertrudis x 1/2 Braunvieh) fed with three lipid supplements in the amount of 0.75% of body weight. The experiment was completely random, using a 3x2 factorial arrangement (3 supplements and 2 supplementation frequencies). The total dry matter intake was higher in August and October compared to November. There was effect of the lipids forms supplied on total dry matter, forage and nutrients intake. During the dry season and beginning of the wet season the animals showed average daily gain of 0.577 g day-1, which were not affected by dietary lipid supplementation and frequencies used. The kind of lipid diet under reduction on the frequency of supplementation alter grazing time. There was no influence of diet lipid and frequencies supplementation on nitrogenous compounds, in the synthesis and efficiency of microbial protein. There was influence of the lipids forms diets on values of rumen pH. Supplementation provided under frequency differences in the concentrations of ammonia in the rumen. There was influence of the lipids forms diets on weight hot carcass, and weight and dress percentage. Supplementation with dietary lipids under different forms and frequencies does not provide differences in body composition... (Complete abstract click electronic access below) / Orientadora: Telma Teresinha Berchielli / Coorientador: Ricardo Andrade Reis / Banca: Alexandre Amstalden Moraes Sampaio / Banca: Ana Cláudia Ruggieri / Banca: Marco Antonio Alvares Balsalobre / Banca: Juliano José de Resende Fernandes / Doutor

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