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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.
81

Deficiência de vitamina A em gestantes adolescentes e seus recém-nascidos : um estudo prospectivo / Vitamin A deficiency in pregnant adolescents and in their newborns : a prospective study

Lima, Geania de Sousa Paz, 1962- 26 August 2018 (has links)
Orientadores: Sílvia de Barros Mazon, Eliana Cotta de Faria / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T00:14:21Z (GMT). No. of bitstreams: 1 Lima_GeaniadeSousaPaz_D.pdf: 1892670 bytes, checksum: 9f00c67f378ca5aa059a0979ca769768 (MD5) Previous issue date: 2014 / Resumo: A alta incidência de gravidez na adolescência e a maior vulnerabilidade desse grupo às deficiências nutricionais são fatos bem documentados. Todavia, a deficiência de vitamina A (DVA), que é considerada problema de saúde pública em países em desenvolvimento, não tem sido devidamente investigada nesse grupo de risco. O presente estudo caracterizou o estado nutricional relativo à vitamina A em gestantes adolescentes e seus recém-nascidos, segundo indicadores dietético, funcional e bioquímico, em um grupo assistido em maternidade escola de Teresina-PI. Inicialmente, 151 gestantes adolescentes sem enfermidades diagnosticadas no período pré-gestacional, não fumantes, na faixa etária de 10 a 19 anos, com 20 semanas ou menos de gestação, sem uso de suplementos vitamínico-minerais contendo vitamina A, aceitaram participar do estudo. Permaneceram até o final 126 gestantes, que foram investigadas quanto às condições socioeconômicas, obstétricas e aos indicadores funcional e dietético. Para identificar a presença de cegueira noturna (XN), no início e final da gravidez, utilizou-se entrevista proposta pela OMS. Para o inquérito alimentar, foram aplicados 03 recordatórios de 24 horas, sendo um no primeiro contato com a gestante (até a 20ª semana de gestação), outro entre a 20ª e 30ª semana e o terceiro após a 30ª semana. Para a avaliação bioquímica da DVA, 89 gestantes tiveram duas amostras sanguíneas seriadas (uma antes da 20ª semana gestacional e outra no pré-parto) e pareadas com as dos recém-nascidos (cordão umbilical). As concentrações séricas de retinol foram determinadas por cromatografia líquida de alta eficiência (CLAE) e o ponto de corte utilizado para caracterizar DVA foi ? 20µg/dL (OMS, 2009). A análise de associação entre as variáveis categóricas foi realizada pelo teste qui-quadrado ou exato de Fisher. A comparação entre variáveis contínuas para amostras pareadas foi realizada pelo teste de Wilcoxon, para amostras não pareadas pelo teste de Mann-Whitney e as análises de correlação pelo teste de Spearman. O nível de significância adotado foi p < 0,05. Os resultados demostraram alta frequência de DVA no grupo estudado, observando-se consumo inadequado de vitamina A em 64% das gestantes; presença de XN (no inicio ou final da gestação) em 13% e concentrações séricas de retinol ? 20µg/dL em 35% das gestantes no início da gestação, evoluindo para 52% no pré-parto. A grande maioria dos recém-nascidos, 95%, apresentou níveis de retinol ? 20µg/dL, observando-se correlação moderada entre as concentrações de retinol materno e do recém-nascido. Considerando o impacto da DVA na saúde da mãe e de seu filho e a alta frequência dessa deficiência observada no presente estudo, ressalta-se a necessidade de avaliação regular do estado nutricional de vitamina A durante o pré-natal do adolescente, a fim de realizar o diagnóstico precoce e tratamento desta deficiência nutricional / Abstract: The high incidence of pregnancy in adolescence and the greater vulnerability of this group to nutritional deficiencies are well documented facts. However, vitamin A deficiency (VAD), which is considered a public health problem in developing countries, has not been sufficiently investigated in pregnant adolescents yet. This study characterizes the nutritional status of vitamin A in pregnant adolescents and in their newborns ¿ both attending a Brazilian public maternity hospital located in Teresina-PI ¿ through functional, dietary and biochemical indicators. Initially, the study included 151 pregnant adolescents who agreed to participate, non-smokers, aged 10-19 years, were at 20 weeks of gestation or less and weren¿t under any kind of treatment with vitamin-mineral supplement containing vitamin A. Until the end of this study, the number of participants reduced to 126 pregnant adolescents, who were investigated in terms of socioeconomic, obstetric and functional indicators, and dietary conditions. The functional indicator, night blindness (XN), was identified at the beginning and at the end of pregnancy; for the dietary survey, three 24 h dietary recalls (R24 h) were applied at intervals ? 5 weeks, and for biochemical assessment of VAD, 89 pregnant adolescents had two serial blood samples collection (one before the 20th gestational week and another at prepartum) paired with their newborns¿ ones. Serum retinol concentrations were determined by high performance liquid chromatography (HPLC) and the cutoff point used to characterize VAD was ? 20?g/dL (WHO, 2009). The analysis of association between categorical variables was performed using chi-square or Fisher's exact test; comparisons of continuous variables between unpaired groups were analyzed by Mann¿Whitney test, and between paired groups by Wilcoxon test; correlation analysis were done by Spearman¿s test. The level of significance was p <0.05. Results showed high occurrence of VAD in the group studied; inadequate intake of vitamin A was observed in 64% of pregnant adolescents; presence of XN (at the beginning or end of pregnancy) in 13%, and retinol concentrations ? 20?g/dL in 35% of the adolescents at the beginning of pregnancy, increasing to 52% at the end. The vast majority of newborns, 95%, had serum retinol ? 20?g/dL, and it was observed moderate correlation between the levels of maternal and newborn retinol. Considering the impact of VAD on health of the adolescent mother-newborn pair, the high prevalence observed in this study emphasizes the need for regular evaluation of the nutritional status of vitamin A during prenatal care of the adolescent, in order to accomplish early diagnosis and treatment of this nutritional deficiency / Doutorado / Ciencias Biomedicas / Doutora em Ciências Médicas
82

Household consumption of orange - fleshed sweet potato and its associated factors in Chipata district, Eastern province, Zambia

Sakala, Patricia January 2017 (has links)
Magister Scientiae (Nutrition Management) - MSc(NM) / Orange-fleshed sweet potato consumption promotion is one of the key nutrition sensitive interventions implementedto address high vitamin A deficiency among the rural population of Zambia since 2011. However, to date no study has been completed regarding household consumption of orange-fleshed sweet potato and factors related to their consumption. The study detailed here therefore sought to establish the consumption of orange-fleshed sweet potato, and to identify factors associated with its household consumption in the Integrating Orange Project areas in Chipata district of Zambia. The study randomly sampled 295 households, and collected information on the household characteristics, production, procurement, consumption and knowledge on orange-fleshed sweet potato. Cross tabulation chi square and one-way analysis of variance were used to identify associated consumption factors. The study found that 86.8% of the households ate orange-fleshed sweet potato; 49.5% ate it 1 to 3 days per week and 30.2% ate it at least 4 or more days per week, and only 13.2% did not consume orange-fleshed sweet potato at all. A relationship was found between having children younger than five years old and consumption of orange-fleshed sweet potato (P < 0.001). Results showed that 8.7% of households with children (n=183) never ate orange-fleshed sweet potato, versus 20.5% of households without children (n=112). Production of orange-fleshed sweet potato (n=178) was found to have a relationship with household conusmption of orange-fleshed sweet potato (P < 0.001). Only 1.1% of households that produced orange-fleshed sweet potato did not consume any, versus 31.6% who did not produce orange-fleshed sweet potato. Purchasing of orange-fleshed sweet potato (n=118) was found to have a relationship with its household consumption (P < 0.001); 56.2% of the households that ate orange-fleshed sweet potato 1 to 3 days during the previous week bought it, compared to only 27.0% of households who ate orange-fleshed sweet potato more than 4 days per week among those that bought it. The respondent‘s knowledge of the health benefits of orange-fleshed sweet potato was found to have a relationship with its consumption in the household (P < 0.001). Only 7.8% of the households where respondents knew the benefits of orange-fleshed sweet potato (n=215) never ate orange-fleshed potato, compared to 50.0% of households where the respondents did not know any benefit (n=80). In contrast, 33.5% of the households where the respondents knew the health benefits ate orange-fleshed sweet potato at least 4 days a week compared to only 7.9% of households where the respondents did not know any benefit. Overall, the study showed that most households consumed orange-fleshed sweet potato. The highconsumption might be due to seasonality, as the study was done during the harvesting season of orange-fleshed sweet potato. Also, prodcution of orange-fleshed sweet potato was promoted in the study area through the Integrating Orange Project. These results therefore suggest that projects seeking to promote consumption of orange-fleshed sweet potato as an intervention for vitamin A deficiency control should promote production of orange-fleshed sweet potato and sensitization of communities on the health benefits of orange-fleshed sweet potato consumption.
83

A Three Months' Study of the Dark Adaptation of a Texas Family During Activity

Wade, Alice Mays January 1941 (has links)
Recent studies have offered an abundance of evidence which indicates that night blindness is caused by vitamin A deficiency. Both adults and children have been used to investigate the relationship between vitamin A deficiency and night blindness.
84

VITAMIN B12 DEFICIENCY ANEMIA-ASSOCIATED MALIGNANCY ACCELERATED BY SUPPLEMENTATION

Vedantam, Venkata Sri Harsha, Nair, Neethu, MOORE, CHRISTINE, Gorman-Nunley, Diana 05 April 2018 (has links)
Vitamin B12 and folate are necessary for bone marrow progenitor growth and division. Deficiencies are common in lymphoproliferative disorders due to increased demands of rapidly growing malignant cells. Isolated vitamin B12 deficiency is seen in 13% of these patients and may be their only manifestation. We present the case of vitamin B12 deficiency anemia due to an underlying malignancy that was discovered following supplementation. A 77-year-old nonsmoker female with chronic kidney disease and hypothyroidism presented to her internist with dyspnea, tachycardia and unintentional 7-pound weight loss. Age-appropriate cancer screenings were up-to-date. Physical exam was notable for an overweight female with tachycardia and trace ankle edema bilaterally. Electrocardiogram demonstrated sinus tachycardia. Labs were remarkable for hemoglobin 10.3 mg/dL (12.1 mg/dL one year ago) and serum B12/mL. She was started on intramuscular vitamin B12 supplementation. At her one-month follow-up, she reported debilitating gastrointestinal distress, rash, and fatigue lasting 5-6 days with every vitamin B12 injection. Physical exam was notable for 20-pound weight loss. Labs revealed hemoglobin 9.9 mg/dL despite serum B12 750 pg/mL and worsening kidney function with marked proteinuria. Additional work-up by primary team and subsequent Hematology & Oncology referral demonstrated elevated M-spike on urine protein electrophoresis and abnormal bone marrow biopsy suspicious for lymphoid malignancy. CT abdomen and whole body PET scan revealed increased uptake in the T12 vertebrae and multiple nodal basins consistent with stage IV lymphoma. Biopsy of vertebral body confirmed diffuse large B-cell lymphoma. The patient received one cycle of chemotherapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). Her course was complicated by pathologic hip fracture requiring hospitalization and surgical repair. The patient died following cardiac arrest in the setting of septic shock from sigmoid colon perforation 7 months from initial presentation. Vitamin B12 and folate play critical roles in nucleic acid synthesis for bone marrow progenitors. Vitamin B12 deficiency arrests cell growth and division, leading to macrocytic anemia and various neuropsychiatric manifestations. It is a common diagnosis with numerous causes: autoantibodies to digestive proteins, poor dietary intake, small bowel malabsorption, etc. Diagnose with low hemoglobin (/dL or 13 mg/dL in non-pregnant women or men, respectively) and mean corpuscular volume >100 fL plus low serum B12 or elevated homocysteine and methyl-malonic acid levels. Replacement is given orally or intramuscularly. Vitamin B12 and folate deficiencies are found in lymphoproliferative disorders due to increased demands of rapidly growing malignant cells. Isolated vitamin B12 deficiency is seen in 13% of patients and may be the only clue. Replacement will not resolve their anemia. Physicians should monitor patients receiving supplementation. If anemia fails to improve or patients experience systemic symptoms, further investigation for lymphoid malignancies is warranted. This patient had dramatic deterioration with acceleration of underlying malignancy following vitamin B12 replacement. We believe supplementation enabled malignant lymphoid precursors to resume cell cycle growth and division. Only one report of vitamin B12 supplementation associated with unmasking a lymphoid malignancy exists in literature. Further research is needed to support whether supplementation can accelerate lymphoid malignancies.
85

The effects of Vitamin A deficiency on lymphocyte transformation.

Mark, David Alan. January 1977 (has links)
Thesis: M.S., Massachusetts Institute of Technology, Department of Nutrition and Food Science, 1977 / Vita. / Bibliography : leaves 64-67. / M.S. / M.S. Massachusetts Institute of Technology, Department of Nutrition and Food Science
86

Vitamin D Insufficiency/Deficiency Management

Kuriacose, Reena, Olive, Kenneth E. 01 January 2014 (has links)
Objectives: In recent years, vitamin D deficiency has been recognized increasingly often in patients, and different supplement regimens have been prescribed to treat it. There has been no consensus on treatment regimens. This study was conducted to determine the management of vitamin D deficiency/insufficiency in outpatient adults in northeast Tennessee. Methods: A retrospective record review was conducted in an internal medicine teaching clinic for patients seen from July 2007YJuly 2008 in Johnson City, Tennessee. A total of 626 nonelectronic charts listed with vitamin D measurements were used in the analysis. Data regarding the level of vitamin D, whether treatment was prescribed, dose and duration of treatment prescribed, and repeat levels of vitamin D, if any were ordered, were collected. Vitamin D deficiency was defined as levels G20 ng/mL; vitamin D insufficiency was defined as levels ranging from 20 to 29.9 ng/mL. Results: Of the 626 patients, 325 (52%) were vitamin D deficient or insufficient. Of these 325 patients, 184 were given a low-dose supplement and 54 received a high-dose supplement. Eighty-seven were either not prescribed any replacement or the dose was unknown (not documented in the chart). The mean change in serum vitamin D levels was significantly different for the high dose compared with the low dose prescribed. There was no significant sex difference in response to the dose given. On average, those who were vitamin D deficient experienced a greater change than those who were insufficient and a greater change, on average, was observed in those who received a higher dose. Conclusions: Vitamin D deficiency and insufficiency are highly prevalent. Clinicians tended to prescribe a high dose of treatment for lower levels of serum vitamin D. The response is higher in high-dose treatment. Documentation regarding whether vitamin D supplements were given or the dose of supplements was given and followed up with repeat levels of vitamin D after treatment was poor.
87

The Relationship of Vitamin D Status to Cardiovascular Risk Factors and Amputation Risk in Veterans With Peripheral Arterial Disease

Gaddipati, Vamsi C., Bailey, Beth A., Kuriacose, Reena, Copeland, Rebecca J., Manning, Todd, Peiris, Alan N. 01 January 2011 (has links)
Objectives: Peripheral arterial disease (PAD) is a common and often overlooked entity responsible for considerable morbidity and mortality. Recent evidence suggests that nontraditional risk factors such as vitamin D may contribute to atherosclerosis. We hypothesized that vitamin D status was associated with cardiovascular risk factors and that vitamin D deficiency (25(OH)D <20 ng/mL) enhanced the risk of amputation. Design: We reviewed medical records of 1435 veterans between 2000 and 2008 in Tennessee via retrospective chart analysis using correlations, logistic regressions, t tests, and χ2 analyses. Results: Vitamin D status was significantly and inversely correlated with body mass index (BMI), glucose, and triglyceride values. Hypertension and diabetes but not smoking also emerged as significantly associated. Of the sample population, 5.2% (n = 75) had an amputation performed. Those individuals who were vitamin D deficient had a significantly higher amputation rate (6.7%) compared with patients who were nondeficient (4.2%). BMI, triglyceride, total cholesterol, hypertension, and diabetes were found to account for 5.7% of the variation in amputation status. Vitamin D concentration and deficiency status accounted for a nonsignificant amount of additional variance. Conclusions: We conclude that vitamin D deficiency is closely linked to increased adiposity, triglyceride, and glucose measurements. Vitamin D deficiency was associated with an increased amputation risk in veterans with PAD and appears to mediate its effects through traditional risk factors.
88

Vitamin D Deficiency: An Increasing Concern in Peripheral Arterial Disease

Gaddipati, Vamsi C., Kuriacose, Reena, Copeland, Rebecca, Bailey, Beth A., Peiris, Alan N. 01 January 2010 (has links)
Peripheral arterial disease is a common and often overlooked entity responsible for considerable morbidity and mortality. Recent evidence suggests that nontraditional risk factors such as vitamin D deficiency may contribute to atherosclerosis and increased cardiovascular morbidity and mortality, hence monitoring of vitamin D status is essential. This review tries to examine this entity.
89

Vitamin D status, growth, and pneumonia in a pediatric Andean population

Mokhtar, Rana Redha 15 June 2016 (has links)
Vitamin D is known to benefit skeletal bone health and prevent rickets in children. Limited evidence exists to support a role of vitamin D in linear growth and stunting, especially in children at high risk for growth faltering, e.g. undernourished low socio-economic status children <5 years. Also, it is unclear if the immunomodulatory benefits of vitamin D impact childhood pneumonia. It is critical to determine whether vitamin D ameliorates stunting and pneumonia, as these conditions are responsible for a high burden of child mortality and morbidity. A secondary analysis of two studies in Ecuador was undertaken to determine the prevalence of vitamin D deficiency and the effect of vitamin D status on growth (height-for-age (HAZ) and weight-for-age (WAZ) z-scores) (n=516) and illness duration in children hospitalized for severe pneumonia (n=348). Serum 25-hydroxyvitamin D (25(OH)D) concentrations of children who participated in a community-based trial (ages 6-36 months) and hospital-based trial (ages 2-59 months) were determined at baseline. Overall, 18.6% of children had serum 25(OH)D levels <17 ng/ml (n=516), 62.2% were stunted (HAZ≤-2), and 65.5% were underweight (WAZ≤-1). Children with 25(OH)D concentrations <17 ng/ml had a higher risk of stunting (HAZ≤-2) than those with concentrations ≥17 ng/ml (ORadj: 2.8; 95%CI: 1.6, 4.7) in logistic regression models. Underweight (WAZ≤-1) children were twice as likely to have 25(OH)D concentrations <17 ng/ml than normal weight children (WAZ>-1) (ORadj: 2.0; 95%CI: 1.2,3.3). Vitamin D deficiency (≤20 ng/ml) did not affect pneumonia duration among hospitalized children in Cox proportional hazard models (HRadj: 1.2; 95% CI: 0.93,1.5). Younger children (2-12 months), underweight children (WAZ≤-2), and children with higher respiratory rates had a longer duration of illness (HRadj: 0.61; 95% CI: 0.43,0.86; HRadj: 0.78; 95% CI: 0.59,1.0; HRadj: 0.97; 95% CI: 0.96,0.99, respectively). Underweight Ecuadorian children are at increased risk for lower serum 25(OH)D concentrations. Low vitamin D status is associated with stunting among undernourished children but not with the duration of pneumonia illness. This indicates that vitamin D may be a modifiable risk factor for stunting, which, if validated in further research, can potentially impart beneficial effects on growth among stunted children in resource limited settings. / 2020-06-30T00:00:00Z
90

Prescorbutic Vitamin C Deficiency and Escape, Avoidance, and Extinction Behavior in Guinea Pigs (Cavia Porcellus)

Goodwin, Susan 01 May 1974 (has links)
Few studies in the area of psychodietetics have concentrated upon the relationship between a single dietary nutrient and behavior. However, some vitamins have been shown to be particularly important to central nervous system activity. Among these is Vitamin C (ascorbic acid). Two experiments were done to determine the effects of ascorbic acid deficient diets on a learning task in which guinea pigs were subjects. Learning was defined as acquisition and extinction of shock-escape and shock-avoidance behavior. In Experiment I, twelve adult guinea pigs were fed diets containing two different deficient amounts of ascorbic acid for six weeks. They were then run on shock-escape, shock-avoidance and extinction schedules. No significant differences in behavior among the dietary groups were shown by statistical analysis, either in acquisition or extinction. In Experiment II, three adult guinea pigs were fed the same ascorbic acid-deficient diets as in Experiment I for six weeks after a baseline performance on a shuttlebox shock avoidance schedule was obtained. Performance after dietary treatment among or across subjects was not observably different from the performance prior to treatment. Serum and adrenal protein analysis confirmed that the dietary treatment had lowered the total ascorbic acid content of the serum and adrenals, but behavior did not show a corresponding or consistent change. These results indicate that ascorbic acid deficient diets fed to adult guinea pigs did not result in a change in behavior as observed on shock-escape, shock-avoidance, or extinction schedules.

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