Background: Nutritional deficiencies are frequent in celiac disease (CeD), and one of the most common is zinc (Zn) deficiency. Supplements are often prescribed to treat Zn deficiency; however, they have been associated with adverse events and reduced absorption of other minerals. Data collected in our clinic showed that 38% of CeD patients would opt for a diet to improve Zn, however, such a diet may be challenging due to food interactions with phytic acid, which blocks Zn absorption. Therefore, the feasibility and efficacy of a Zn-optimized diet compared to supplementation is unknown. Aims: To assess the feasibility of the protocol and collect data on estimated effect sizes for secondary outcomes to plan a properly powered randomized controlled trial (RCT). Methods: We conducted an open-label, pilot RCT. CeD patients were randomized to Zn supplementation (Zn gluconate 25mg) or a Zn-optimized diet for 3 months and followed up with a 3-month pragmatic approach. We evaluated enrollment rates and adherence to both interventions. Plasma and urine Zn, stool samples, and questionnaires were collected pre- and post-intervention. Results: We enrolled 28 participants and 16 of them have completed the study. Interim analysis shows an enrollment fraction of 26% (i.e. 28/108 eligible participants), and a dropout rate of 17.9%. Eighty-two % of participants allocated to the Zn-supplement intervention and 50% in the dietary intervention were compliant at 3 months. Based on the effect size for normalization of plasma Zn at 3 months, 142 participants are required for an adequately powered RCT in the future. There were no significant differences in gastrointestinal or extra-intestinal symptoms, quality of life, anxiety and depression or adverse events between interventions. Conclusion: Based on this preliminary analysis, recruitment of participants will take 6 months longer than expected. Assessment of reasons for diet non-adherence will allow implementation of strategies to improve feasibility. / Thesis / Master of Science in Medical Sciences (MSMS)

Made available in DSpace on 2015-03-26T13:53:16Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2894312 bytes, checksum: 8e4e6d33bfbb1f07f987dfb380479055 (MD5) Previous issue date: 2010-07-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The coffee tree is a demanding plant in micronutrients, especially Zn, and the P x Zn interaction is an important issue for the management of tropical soils, due to the use of high doses of P in soils with low availability of this nutrient. In this work was studied the seedlings response of Coffea arabica L. cv. Catuaí to doses of Zn and P, including the supply of P corresponding to a high availability of P, therefore, a high antagonism potential to the availability of Zn. The experiment was carried out in a greenhouse in the period between the October/2009 and January/2010 (122 days of conducting the experiment), using 4 × 4 factorial design, distributed in randomized blocks, with three replications, being four doses of Zn (0, 5, 15, and 45 mg / dm 3 of soil) and P (0, 200, 600 and 1,800 mg / dm 3 of soil). On the soil, having as a source ZnSO 4 .7 H 2O, the doses of Zn were applied trough a soil solution and P levels were incorporated, being the source the triple superphosphate. It was used samples of a Red Yellow sandy-loam originating from Três Marias - MG and coffee seedlings with four pairs of leaves, which were transplanted to pots (2 dm 3 of soil), maintaining soil moisture near to field capacity. It was evaluated the total content of Zn in plant parts (leaf, stem and root), the soluble fraction of Zn (leaf), the levels of total P (leaf, stem and root), the enzyme superoxide dismutase (SOD) , plant height, number of nodes per plant, average length of internodes and dry matter production (leaf, stem and root). There were no significant changes in levels of total Zn in leaves with increasing doses of P added to soil, although the levels of soluble Zn (active) have fallen, indicating, in this case, antagonistic interaction between the variables. The SOD activity was reduced with increasing doses of Zn added to soil. The growth of coffee seedlings was influenced by the interaction between P and Zn. / O cafeeiro é uma planta exigente em micronutrientes, especialmente, em Zn, e a interação P x Zn é uma questão importante para o manejo de solos tropicais, haja vista a utilização de altas doses de P em solos com baixa disponibilidade deste nutriente. Neste trabalho foi estudada a resposta de mudas de Coffea arabica L. cv. Catuaí às doses de Zn e P, incluindo-se o suprimento de P que correspondeu a uma alta disponibilidade de P, portanto, a um alto potencial de antagonismo em relação à disponibilidade de Zn. O experimento foi conduzido em casa-de-vegetação entre o período de outubro/2009 a janeiro/2010 (122 dias de condução do experimento), utilizando esquema fatorial 4 × 4, distribuído em blocos casualizados, com três repetições, sendo quatro doses de Zn (0, 5, 15, e 45 mg/dm3 de solo) e quatro doses de P (0, 200, 600 e 1.800 mg/dm3 de solo). No solo, tendo como fonte ZnSO4.7H2O, as doses de Zn foram aplicadas em solução via solo, e as doses de P foram incorporadas, sendo a fonte o superfosfato triplo. Utilizaram-se amostras de um Latossolo Vermelho Amarelo textura franco-arenosa originário de Três Marias – MG e mudas de café com quatro pares de folhas, que foram transplantadas para vasos (2 dm3 de solo), mantendo-se a umidade do solo próxima à capacidade de campo. Avaliaram-se o teor total de Zn nos órgãos das plantas (folha, caule e raiz) e a fração solúvel de Zn (folha), os teores totais de P (folha, caule e raiz), atividade da enzima superóxido dismutase (SOD), altura de plantas, número de nós por planta, comprimento médio dos entrenós e produção de matéria seca (folha, caule e raiz). Não houve alterações significativas nos teores de Zn total nas folhas com o aumento das doses de P adicionadas ao solo, embora os teores de Zn solúvel (ativo) tenham diminuído, indicando, neste caso, interação antagônica entre as variáveis. A atividade da SOD foi reduzida com o aumento nas doses de Zn adicionadas ao solo. O crescimento das mudas de café foi influenciado pela interação P e Zn.