• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 31
  • 22
  • 8
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 80
  • 80
  • 80
  • 32
  • 30
  • 15
  • 13
  • 11
  • 11
  • 9
  • 9
  • 9
  • 9
  • 8
  • 7
  • 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.
21

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.
22

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.
23

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.
24

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
25

Assessing the Prevalence and Characteristics of Vitamin D Deficiency in Hemodialysis Patients in a Long Term Acute Care Hospital

Wolf, Emily A. January 2011 (has links)
No description available.
26

Decoding Adolescent Rickets: The Effects of the Environmental and Social Contexts on the Development of Rickets in Adolescents in the Netherlands from the 17th to 19th Centuries

Lamer, Madeleine January 2020 (has links)
Vitamin D deficiency at Middenbeemster and Hattem is the result of cultural variables that limit an individual’s exposure to sunlight. During growth spurts, such as the pubertal growth spurt, high demand for vitamin D puts individuals at an increased risk for developing conditions such as rickets. This thesis aims to determine whether adolescent rickets can be identified in archaeological skeletal remains, and how to quantify the observed changes. The current work also aims to use the prevalence of adolescent rickets to understand the underlying social changes affecting individuals in the Netherlands in the 17th to 19th centuries. Two collections of archaeological human remains from the 17th to 19th century Dutch sites of Middenbeemster (n=246) and Hattem (n=117) were evaluated using macroscopic, metric, radiographic, and micro-CT analysis of skeletal remains. Adolescent individuals were evaluated for signs of active adolescent rickets, and adults were evaluated for signs of residual adolescent rickets. Statistical analysis found that measurements quantifying shape changes at the distal ulna, medial clavicle, and sacral angle can be used to identify adolescent rickets in a skeletal sample. Adolescent rickets at Middenbeemster and Hattem was found to be distributed equally amongst males and females and was found to occur less frequently than rickets in infants and children from the same population. Rickets in adolescents was most likely caused by the onset of new jobs or roles resulting in individuals remaining indoors for long periods of time. Rickets may have also been caused by illness. By identifying rickets in adolescents, this thesis provides a window to view the changing roles of individuals as they begin to occupy new spaces in their transition from children into adults, thus providing a novel way to investigate the lives of adolescents. / Thesis / Master of Arts (MA)
27

Concentrações séricas de vitamina D em lactentes saudáveis / Serum vitamin D concentrations in healthy infants

Ane Cristina Fayão Almeida 26 January 2018 (has links)
Introdução: Uma elevada prevalência de deficiência de vitamina D (DVD) em crianças tem sido observada em todo o mundo, mas poucos são os estudos com relação ao estado nutricional da vitamina D (VD) em lactentes saudáveis. A principal causa da deficiência em crianças saudáveis é o aleitamento materno sem suplementação e a falta ou insuficiência de exposição solar. Objetivos: Determinar as concentrações séricas de VD e verificar sua associação com concentrações de paratormônio (PTH), fosfatase alcalina (FA), cálcio (Ca), fósforo (P) e albumina e uso da suplementação de VD em lactentes saudáveis com idades entre >= 6 e <= 24 meses atendidos em duas Unidades Básicas de Saúde do município de Ribeirão Preto, SP, Brasil. Métodos: Estudo transversal, observacional e analítico em que foram determinadas as concentrações séricas de 25 (OH)D, PTH, FA, Ca, P e albumina de 155 lactentes saudáveis. Informações sobre exposição solar, aspectos sociodemográficos das mães e características clínico-nutricionais dos lactentes foram obtidas por entrevistas com os responsáveis dos lactentes. Concentrações séricas de 25(OH)D maiores que 20ng/ml foram consideradas adequadas, entre 12 a 20ng/ml insuficientes e < 12ng/ml deficientes. Resultados: Dez lactentes (6,5%, Intervalo de Confiança 95% 3,5-11,4) apresentaram insuficiência de VD e nenhum apresentou DVD. Nenhuma alteração nas concentrações séricas de P, Ca e albumina foram detectadas. Apenas um lactente apresentou aumento nas concentrações séricas de PTH e 35,5% dos lactentes apresentaram FA elevada, porém nenhum apresentou DVD ou insuficiência de VD. Não foram encontradas associações entre as concentrações séricas de 25(OH)D e as de FA, Ca e albumina. Houve associação entre concentrações séricas de 25(OH)D e PTH mesmo após ajuste para sexo, idade e Índice de Massa Corporal; também foi observada associação entre concentrações séricas de 25(OH)D e P apenas após o ajuste pelas covariáveis. Não foram verificadas associações entre insuficiência de VD, exposição solar e suplementação de VD. Conclusões: Uma baixa prevalência de concentrações insuficientes de 25(OH)D foi observada. Não foram encontradas associações entre as concentrações séricas de 25(OH)D e PTH, FA, Ca, P e albumina. Da mesma forma, não foram encontradas associações entre de concentrações séricas de 25(OH)D, exposição solar e suplementação de VD. / Introduction: A high prevalence of vitamin D deficiency (VDD) in children has been observed worldwide, but there are few studies on the nutritional status of vitamin D (VD) in healthy infants. The main cause of deficiency in healthy children is breastfeeding without supplementation and lack or insufficiency of sun exposure. Objective: To determine serum concentrations of VD and verify its association with parathyroid hormone (PTH) levels and use of VD supplementation in healthy infants aged >= 6 to <= 24 months attended at two Basic Health Units in Ribeirão Preto city, São Paulo, Brazil. Methods: A cross-sectional, observational and analytical study was performed in which were determined serum concentrations of 25 (OH) D, PTH, alkaline phosphatase (AP), calcium (Ca), phosphorus (P) and albumin of 155 healthy infants. Information of sun exposure, sociodemographic aspects of mothers and clinical and nutritional characteristics of infants were obtained through interviews with responsible for infants. Serum concentrations of 25(OH)D greater than 20ng / ml were considered adequate, between 12 to 20ng / ml insufficient and <12ng/ml, deficient. Results: Ten infants (6.5%, 95% Confidence Interval 3.5-11.4) presented VD insufficiency and none presented DVD. Only one infant had an increase in PTH serum concentrations and 35.5% of infants had high AP but none presented DVD or VD insufficiency. No changes in serum P, Ca and albumin concentrations were detected. No associations were found between serum concentrations of 25 (OH) D and AP, Ca and albumin. There was an association between serum concentrations of 25(OH)D and PTH even after adjusting for sex, age and body mass index; an association between serum concentrations of 25(OH)D and P was observed only after adjustment for covariates. There were no associations between VD insufficiency, sun exposure and VD supplementation. Conclusions: A low prevalence of insufficient concentrations of 25 (OH)D was observed. No associations were found between serum concentrations of 25 (OH)D and PTH, FA, Ca, P and albumin. Likewise, no associations were found between serum concentrations of 25 (OH)D, sun exposure and VD supplementation.
28

Vitamin D and endothelial function in chronic kidney disease

Dreyer, Gavin January 2014 (has links)
Vitamin D deficiency in patients with chronic kidney disease, measured by reduced serum concentrations of 25 hydroxy vitamin D, is highly prevalent and associated with both endothelial dysfunction and an increased risk of cardiovascular disease. Observational studies in chronic kidney disease have demonstrated that vitamin D therapy reduces the risk of cardiovascular disease. In patients with chronic kidney disease and concomitant vitamin D deficiency, the effect of vitamin D therapy on endothelial function, which is associated with cardiovascular disease, is poorly understood. The mechanism by which vitamin D affects endothelial function is unclear. Methods Presented in this thesis, two studies have addressed these issues: 1. A double blind, randomized controlled trial evaluating the effect of ergocalciferol compared to placebo on microcirculatory endothelial function in patients with non-dialysis chronic kidney disease and concomitant vitamin D deficiency 2. In vitro and in vivo experiments to determine the mechanistic effect of ergocalciferol on endothelial function in an experimental model of uraemia. Results In the clinical study, ergocalciferol increased vitamin D serum concentrations and improved microcirculatory endothelial function measured by laser Doppler flowmetry after iontophoresis of acetylcholine. Oxidative stress measured by skin autofluorescence for advanced glycation end products did not change in the ergocalciferol group but increased significantly in the placebo group. Ergocalciferol increased endothelial nitric oxide synthase expression and activity in cultured human endothelial cells and improved endothelial function in an in vivo model of mild uraemia. The findings from the in vivo and clinical studies occurred independently of changes in blood pressure, conduit artery function, serum calcium, phosphate and parathyroid hormone supporting in vitro findings that ergocalciferol acts directly on the endothelium. Conclusion Ergocalciferol improved endothelial function in both rodent and human subjects with chronic kidney disease. Experimental evidence suggests this effect occurs through an endothelium dependent mechanism involving changes in the upregulation and function of endothelial nitric oxide synthase.
29

Seasonal changes and serum 25-hydroxyvitamin D levels among community-dwelling elders who live in Boston, Massachusetts and Stockholm, Sweden

Chang, Kuang-Wei 01 November 2017 (has links)
BACKGROUND: The prevalence of Vitamin D deficiency is roughly 40% in the world and is increasing every year. Populations 65 years and older show a higher prevalence of vitamin D deficiency, because the aging process decreases the capacity of the skin to produce vitamin D. Some studies have reported that the prevalence of vitamin D deficiency is higher in the winter, however the effect of seasonal change on serum vitamin D level remains controversial in some specific populations. Moreover, this association remains uncertain in the elderly population because there is no study that specifically targets individuals over the age of 65. This study investigated the effect of seasonal changes and serum 25-hydroxyvitamin D among individuals 65 years and older residing in the Boston, Massachusetts and Stockholm, Sweden. METHODS: Cross-sectional and longitudinal cohort designs were both adapted to examine an existing data from VIVE2 parent study; the data was collected from 2012 to 2014. Data from the subjects who had finished this 6-month trial were analyzed for this study. Serum 25(OH)D levels, BMI, sex, study sites and age were collected and analyzed by univariate regression analysis and t-test. Serum 25(OH)D and confounders were included in multivariate analysis. Study sites were analyzed by effect modification model. RESULTS: In total, the prevalence of vitamin D deficiency (serum 25(OH)D levels less than 20 ng/ml) was 70%, while the mean serum 25(OH)D level was 20 ng/ml in summer and 16.4 ng/ml in winter. The average of seasonal serum 25(OH)D level changes were 6 ng/ml and 3 ng/ml in Stockholm, Sweden and Boston, MA, respectively. In addition, the prevalence of vitamin D deficiency increased 80% during winter (95CI: 1.1 – 2.9). There was no significant different in serum 25(OH)D levels among elderly populations between low latitude study site Boston, MA and high latitude site Stockholm, Sweden. There was no significant relation found in BMI, age and sex with serum 25(OH)D levels in the study. The seasonal serum 25(OH)D level changes was significantly different in the cross-sectional study design but not in the longitudinal study. CONCLUSION: Serum 25(OH)D levels were higher in the summer than in the winter among the elderly population resided in Boston, MA and Stockholm, Sweden.
30

Comparative analysis of vitamin D content in sardines canned in olive oil and water

Kalajian, Tyler Arek 18 June 2016 (has links)
Vitamin D is a fat-soluble hormone primarily responsible in maintaining plasma calcium and phosphorus homeostasis in humans. Vitamin D insufficiency and deficiency is a global health issue. Very few foods naturally contain vitamin D; a major source is oily fish such as salmon. Several studies have analyzed vitamin D content in various fish, however studies concerning canned fish are lacking. In particular, this study was interested in evaluating the vitamin D content in canned sardines in not only the whole fish but also in the olive oil or water it was canned in. It was hypothesized that the vitamin D content in sardines canned in water would be greater than sardines canned in olive oil due to the fat-soluble nature of vitamin D to be more easily extracted into olive oil than water. Sardines (~100g) canned in olive oil had a slightly greater vitamin D content than the sardines in water (2,555.6±234.2 and 1,993.7±2,411.3 IUs (p<0.05) respectively). An evaluation of the vitamin D3 content in the olive oil and water used to can the sardines revealed 701.4±471.1 and 149.1±42.2 IUs in the total olive oil and water respectively recovered from the cans. It was determined that of the total vitamin D content in the can (sardines in olive oil or water) 20.9%±12.8% of vitamin D3 is found in the olive oil compared to only 14.2%±10.4% (p<0.05) vitamin D3 found in water. These results support the concept that sardines packed in olive oil may have less vitamin D3 than similar sardines packed in water. The analysis of the sardines revealed that they had more than 13 times the amount of vitamin D3 than that is reported in the USDA table of nutritional facts for canned sardines. This could be because the sardines were caught in the summer months when they are more likely to be consuming food containing vitamin D3 as a result of reduced synthesis of vitamin D3 in zooplankton and other lower life forms that the sardines consume. An alternative explanation for this increase in vitamin D3 content is the process of canning the sardines. Vital Choice, the supplier of the sardines, immediately ices the fish upon retrieval from the ocean (to ensure freshness) and then are canned in less than 5 hours after being caught. This process of freshness preservation could explain why the vitamin D content was so high; possibly an accurate representation of the original vitamin D content in the sardines.

Page generated in 0.0643 seconds