824 Clinical Trials for Various Conditions
The investigators hypothesize that single oral high dose supplementation with vitamin A will reduce the incidence of moderate-severe chronic graft-versus-host disease (GVHD) compared with placebo.
The goal of this clinical trial is to measure how well different formulations of vitamin A (VA) are absorbed by the body when they are added to bouillon (broth) as vitamin A palmitate (VAP). Fortifying bouillon cubes with VA is one potential approach to addressing VA deficiency, which is a major public health issue in many low- and lower-income countries. The main question this study aims to answer is to compare the amount of VA that is absorbed by the body from three different VAP formulations that are added to bouillon. Participants will consume different formulations of VA and have multiple blood collections.
This study will determine systemic vitamin A status and lesion histopathology of participants with vocal fold hyperkeratosis resulting in clinical leukoplakia.
Women of reproductive age had their vitamin A stores estimated by retinol isotope dilution and then were given vitamin A supplements near the US vitamin A RDA or placebo for 42(USA) or 60 (Indonesia) days, after which retinol isotope dilution was repeated and the change in vitamin A stores was determined in each group to estimate how much vitamin A is needed to maintain nutrient balance in these women.
This trial studies how well high dose vitamin A compound works in treating participants with non-small cell lung cancer that can be removed by surgery. Vitamin A compound may increase the number of germinal centers (immune centers that make antibodies mature) in tumor and lymph tissues which may be beneficial to patients with cancer.
This phase I trial studies the side effects and how well high dose vitamin A works in preventing gastrointestinal graft versus host disease (GVHD) in participants undergoing donor stem cell transplant. Vitamin A deficiency is associated with increased risk of gastrointestinal GVHD. Vitamin A regulates growth and differentiation of intestinal cells and may reduce risk of gastrointestinal GVHD.
This study establishes the safety and efficacy of vit A supplementation doses (3000 and 6000 IU/d) over 8 weeks in children with SCD-SS, ages 9 and older and test the impact of vit A supplementation on key functional and clinical outcomes. Additionally, vitamin A status is assessed in healthy children ages 9 and older to compare to subjects with SCD-SS.
Background: Age-related macular degeneration (AMD) is an eye disease. It is the leading cause of vision loss in people over 55 in the U.S. Changes in the eye can make it difficult for they eye to adjust to low light. This is known as dark adaptation. This is particularly significant in people with reticular pseudodrusen (RPD). Identifying and watching the early to middle stages of AMD and changes in dark adaptation might help researchers learn to stop the disease before it becomes severe. Taking vitamin A might help improve vision in people with RPD. Objectives: To see if taking 16,000 IU of vitamin A per day improves vision in people with RPD. Also to improve understanding of RPD and associated dark adaptation. Eligibility: Adults ages 50 and older with RPD and normal liver function Design: Participants will be screened with: Medical and eye disease history Eye exam: The pupil will be dilated with eye drops. Pictures will be taken of the retina and the inside of the eye. Including the screening visit, participants will have at least 5 visits. They will be about once a month over 6 months and last 4-6 hours. Visits include: Questions about eye problems in certain light Eye exam Blood and urine tests Dark adaptation protocol: Participants will sit at a machine in a dark room. They will look into the machine and push a button when they see a light. This lasts 20-40 minutes. Participants will take a vitamin A supplement by mouth once a day for 2 months. They will record when they take the pills in a diary.
Background: Age-related macular degeneration (AMD) is an eye disease. It is the leading cause of vision loss in people over 55 in the U.S. Changes in the eye can make it difficult for the eye to adjust to low light. This is known as dark adaptation. Identifying and watching the early to middle stages of AMD and changes in dark adaptation might help researchers develop new treatments to stop the disease before it becomes severe. Taking vitamin A might help improve vision in people with AMD. Objectives: To see if taking 16,000 IU of vitamin A per day improves vision in people with AMD. Also to improve understanding of AMD and associated dark adaptation. Eligibility: Adults ages 50 and older with AMD and normal liver function Design: Participants will be screened with: Medical and eye disease history Eye exam: The pupil will be dilated with eye drops. Pictures will be taken of the retina and the inside of the eye. Including the screening visit, participants will have at least 5 visits. They will be about once a month over 6 months. Visits include: Questions about eye problems in certain light Eye exam Blood and urine tests Dark adaptation protocol: Participants will sit at a machine in a dark room. They will look into the machine and push a button when they see a light. This lasts 20-30 minutes. Participants will take a vitamin A supplement by mouth once a day for 2 months. They will record when they take the pills in a diary.
Minimal human data exist on actual liver vitamin A compared with blood biomarkers. One blood biomarker, the percent of total serum retinol (vitamin A) in the form of retinyl esters, has been suggested to diagnose hypervitaminosis A with cutoffs of 5% and 10%. In this study, investigators aim to compare total liver vitamin A reserves with the percent total serum retinol as retinyl esters to evaluate hypervitaminosis A using autopsy samples from US adults. Investigators also evaluate the sensitivity (the ability of the biomarker to correctly identify those with deficiency) and specificity (the ability of the biomarker to correctly identify those without deficiency) of serum retinol to determine vitamin A deficiency, variation of liver vitamin A concentration among lobes, and liver alpha retinyl ester concentrations, a cleavage product of alpha-carotene, a vitamin A precursor. To conduct the study, matched serum and liver samples were procured from 27 US adult cadavers (from donors age 49-101 years) and their vitamin A biomarkers were analyzed.
Women were given a vitamin A tracer, and blood was sampled to determine individual and group vitamin A kinetics. Data were subsequently modeled using compartmental analysis to determine effects of study length on model outcomes.
The investigators hypothesize that supplementation with vitamins A and D will reduce the incidence of acute gastrointestinal graft versus host disease (GI GVHD) compared with supplementation with vitamin D alone.
The primary objective of this study is to establish that single dose vitamin A supplementation is feasible and safe in pediatric and young adult bone marrow transplant recipients until day +30 (± 7 days) after hematopoietic stem cell transplantation.
Children are particularly vulnerable to respiratory virus infections, especially influenza. Vitamin A \& D deficiencies are associated with vulnerability to infectious diseases of the respiratory tract. The central hypothesis of this protocol is that vitamin supplements will enhance antibody responses toward the flu vaccine in children. Children, 2-8 years old, will be randomized to receive influenza virus vaccine with a vitamin A+D supplement or influenza virus vaccine with placebo. Children will be tested for vitamin levels and immune responses before and after influenza virus vaccinations to determine if vitamin supplementation improves the influenza virus vaccine-induced immune response. PRIMARY OBJECTIVE: * To assess the vaccine-induced and total antibody (including IgG and IgA) response after influenza virus vaccine administration and IgA/IgG plus IgA/IgM ratios at 28 and 56 days in sera SECONDARY OBJECTIVE: * To assess the neutralizing response toward influenza virus vaccine in the sera.
The goal of the research study is to determine the absorption, metabolism, and bioconversion of carotenoids such as beta-carotene to vitamin A from gari made with biofortified cassava compared to a mixture of red palm oil and gari made from typical white cassava.
Vitamin A deficiency (VAD) increases the risk of death from infections in infants and young children. The World Health Organization (WHO) recommends high-dose vitamin A supplementation (VAS) from 6-59 months of age to reduce the risk of death in countries where VAD is common. Such countries include Bangladesh, where this study is being conducted. While providing VAS at 6 months is recommended, providing VAS at birth may also decrease the risk of death since newborn infants are also at risk of VAD. VAS presumably reduces infant mortality by improving the immune response to infection and immunization. Vitamin A particularly affects the development and function of T cells, which develop in the thymus and are a key component of the memory response to infection and immunization. Vitamin A is important for development of an important class of T cells, regulatory T-cells, in the intestine. Regulatory T-cells prevent over-reaction of the immune system to substances the immune system might otherwise treat as harmful such as food or the healthy bacteria in the intestine. VAD could disrupt the normal colonization of the infant's intestinal tract and cause a condition called "dysbiosis" where abnormal bacteria flourish and adversely affect the infant's immune system. Dysbiosis may disrupt the immune response to injectable and oral vaccines. VAS at birth may prevent dysbiosis and thus improve immune function, response to vaccines, and child survival. The investigators recently completed an intervention trial in Bangladeshi infants (NCT01583972) examining the effect of VAS at birth on immune function and response to vaccines administered from birth to 14 wk of age. The present study will recruit infants who completed NCT01583972 when they are from 12 to 24 m of age to determine if VAS at birth affects the responses to these same vaccines when they are measured during the second year of life. The investigators will examine the effect of VAS at birth on gut microbiota measured early in infancy and during the second year of life, and explore the association of the gut microbiota with vaccine response. Mothers of study infants will participate in the study because the breast milk oligosaccharide content strongly affects gut microbiota composition and the "secretor status" of the mother, which can be determined from maternal FUT2 genotype, strongly affects breast milk oligosaccharide content.
The purpose of this study is to determine the vitamin A equivalents in high-carotenoid varieties of cassava.
This multi-site, randomized trial was conducted to determine the safety and effectiveness of a higher dose of vitamin A and determine if this would increase the rate of survival without bronchopulmonary dysplasia (BPD) and reduce the risk of sepsis. Infants with birth weights from 401-1000g and who were on mechanical ventilation or supplemental oxygen at 24-96 hours of age were enrolled. Subjects were randomized to either the Vitamin A or a control group. Infants in the Vitamin A group were given a dose of 5000 IU (0.1 ml) intramuscularly on Mondays, Wednesdays, and Fridays for four weeks. Control infants received a sham procedure rather than placebo injections.
The goal of this protocol is to determine the vitamin A value (equivalence) of spirulina. The investigation will use intrinsically deuterium labeled spirulina and an isotope vitamin A reference dose, 13C10- retinyl acetate (13C10 RAc), in males (n=20). Up to 45 blood samples (10 ml/sample) will be collected from each subject over a two-month period to evaluate the bioavailability and bioconversion of spirulina ß-carotene to vitamin A.
Our objectives will be to test the following hypotheses and to make the following determinations: (1) The absorption and bio-conversion of provitamin A carotenes taken by children are different between spinach, Golden Rice, and ß-C in oil capsules. (2) The absorption of provitamin A carotenes and their bioconversion to vitamin A are different in children with or without adequate vitamin A nutrition. (3) To define the vitamin A equivalence(s) of dietary spinach, Golden Rice, and a ß-C in oil dose by using an isotope reference method in children with or without adequate vitamin A nutrition and to compare those values with values derived from model based compartmental analysis. (4) To determine the number and time of blood samples needed for future studies in various field settings on the retinol equivalence of a large number of plant sources.
We wish to understand the association of Vitamin A serum levels and Vitamin A receptor number and responsiveness in asthmatics. We believe that Vitamin A receptors may be less prevalent in asthmatics and their responsiveness decreased.
The purpose of this trial is to determine whether lutein in addition to vitamin A will slow the course of retinitis pigmentosa.
The objectives of this study are to evaluate the safety and efficacy of 0.5% retinol (Vitamin A) versus it's vehicle cream in the treatment and prevention of skin aging and Bateman's Purpura (bruising).
Children with malnutrition are often low in some nutrients, like zinc or vitamin A, that could help them fight off infections like pneumonia. Our study was designed to see if children who got supplements of zinc or vitamin A had fewer infections.
The purpose of this trial is to determine whether providing women with a weekly oral supplement of vitamin A, either preformed or as beta-carotene, at a dosage equivalent to a recommended intake from early pregnancy through three months postpartum, can reduce the risk of maternal mortality, fetal loss, or infant mortality.
Retinitis pigmentosa (RP) is a collective term for a group of inherited retinal dystrophies that are a major cause of irreversible blindness. RP of some type occurs in approximately 1 out of 3500 persons in the United States(1). Gene mutations are responsible for the majority of RP. To date, mutations have been identified in 30 different genes linked to RP(2). The visual prognosis of RP is poor, since the gradual but relentless visual field loss leads eventually to some degree of blindness(3). Although no effective treatment for RP has been identified, participants supplemented with a daily oral dose of 15,000 IU vitamin A palmitate have shown, on average, a slower rate of deterioration of retinal function when the intervention is continued over several years(4). The purpose of this research is to determine whether administration of high oral doses of vitamin A can acutely improve cone photoreceptor function in RP participants as measured by electroretinography (ERG). In this interventional, non-randomized, prospective, pilot study, 5 participants will receive a daily oral dose of 50,000 IU of vitamin A palmitate for 4 weeks, followed by a maintenance dose of 15,000 IU daily for the subsequent 2 weeks. The primary efficacy outcome is a relative percentage change in ERG response amplitude subsequent to vitamin A supplementation. A secondary efficacy outcome is a relative percentage change in implicit time from pre- to post- vitamin A supplementation, with improvement specified as a shorter response implicit time. Other secondary outcomes will be improvements in visual field (Humphery, 10-2; sum of thresholds). Safety outcomes include visual fields, ETDRS visual acuity, intraocular pressure, serum vitamin A level and liver function tests.
Extremely low birth weight infants have decreased blood levels of Vitamin A. This Vitamin A deficiency may increase the risk of infections and chronic lung disease in these infants. This study will examine the effects of Vitamin A supplementation in premature babies born weighing less than 1500 grams (3.3 lbs).
The purpose of this trial is to determine whether a nutritional supplement in addition to vitamin A will slow the course of retinitis pigmentosa.
Plant-based milk alternatives (PBMAs) are a popular alternative to cow's milk. The different types of PBMAs on the market shelf include almond, oat, soy, coconut, cashew, pea, hemp, and rice. Among these, PBMA made from almonds, oats and soy are the most popular in North America. Though PBMAs are designed to mimic cow's milk in terms of color, they often have a very different nutrition profile. In order to better substitute for cow's milk, PBMAs often have added vitamins and minerals, as well as added sugars and flavorings to improve flavor. This study will test how well certain nutrients (vitamin D, calcium, potassium, and magnesium) are absorbed by the body after intake of milk and PBMAs. Nutrient absorption will be measured using blood samples after short term intake (from 1 hours to 1 week) of almond, soy, and oat milk, and compare it to cow's milk. Participants in the study will avoid all fluid dairy products and vitamin-D supplemented foods for three weeks and then be asked to consume either almond, soy, oat, or cow's milk for one week. All participants will visit the Clinical Nutrition Research Center (CNRC) four times over the course of about one month. These visits include a screening and pre-study visit (1.5 hrs), a pick-up visit (30 min), one long study day visit (\~11 hours), and two shorter follow up study day visits (1 hr).
This proposed pilot study will assess if the Patch Technology system will increase adherence in patients with cystic fibrosis followed at the UTHSCSA Cystic Fibrosis Center.