Search results for "vitamin D."
showing 10 items of 265 documents
Identification of polymorphic variants associated with erlotinib-related skin toxicity in advanced non-small cell lung cancer patients by DMET microa…
2016
Purpose: Erlotinib is a targeted agent commonly used in advanced non-small cell lung cancer (aNSCLC). However, drug-related skin toxicity often may affect the quality of life of cancer patients and lead to treatment discontinuation. Genetic polymorphisms in drug transporters and metabolizing enzymes play a major role in the interindividual variability in terms of efficacy and toxicity of erlotinib treatment. The aim of our study was to identify genetic determinants in adsorption, distribution, metabolism, and excretion genes influencing skin rash (SR) by the novel drug-metabolizing enzyme and transporter (DMET) microarray Affymetrix platform in aNSCLC patients. Methods: In a retrospective s…
Standardized measurement of circulating vitamin D [25(OH)D] and its putative role as a serum biomarker in Alzheimer's disease and Parkinson's disease
2019
The current review provides an overview on the development of 25(OH)D measurement standardization tools over the last three decades and clarifies whether there is a role as a serum biomarker for vitamin D in neurological diseases. In the past, a lack of internationally recognized 25(OH)D reference measurement procedures and reference standard materials led to unstandardized serum total 25(OH)D results among research and clinical care laboratories. The vitamin D Standardization Program (VDSP) has been introduced in 2010 to address this problem, however, vitamin D External Quality Assessment Scheme (DEQAS) reports still show substantial sample- to- sample variability. Further, immunoassays, w…
Current practice in nutrition after allogeneic hematopoietic stem cell transplantation – Results from a survey among hematopoietic stem cell transpla…
2021
Summary Background Allogeneic hematopoietic stem cell transplantation (alloHSCT) is frequently associated with impaired oral intake and malnutrition, which potentially increases morbidity and mortality. Therefore, nutrition is one of the major challenges in the post-transplant period. Methods To document the current clinical approach in nutritional treatment, we designed a questionnaire concerning the current practice in nutrition after alloHSCT and distributed it to German speaking centers performing alloHSCT in Germany, Austria and Switzerland between November 2018 and March 2020. Twenty-eight (39%) of 72 contacted centers completed the survey, 23 from Germany, two from Austria and three …
Vitamin D and Its Analogues Decrease Amyloid-β (Aβ) Formation and Increase Aβ-Degradation
2017
Alzheimer’s disease (AD) is characterized by extracellular plaques in the brain, mainly consisting of amyloid-β (Aβ), as derived from sequential cleavage of the amyloid precursor protein. Epidemiological studies suggest a tight link between hypovitaminosis of the secosteroid vitamin D and AD. Besides decreased vitamin D level in AD patients, an effect of vitamin D on Aβ-homeostasis is discussed. However, the exact underlying mechanisms remain to be elucidated and nothing is known about the potential effect of vitamin D analogues. Here we systematically investigate the effect of vitamin D and therapeutically used analogues (maxacalcitol, calcipotriol, alfacalcidol, paricalcitol, doxercalcife…
Effect of dietary interventions during weaning period on parental practice and lipoproteins and vitamin D status in two-year-old children
2016
ABSTRACT Objective: Evaluate if a two-day course for parents on nutrition and applied baby food preparation had an effect on child’s intake of home-made foods, lipid concentration, and vitamin D status. Design: Randomized controlled trial at age 6 months and follow-up at ages 15 and 24 months. Setting: Four health care clinics in Kristiansand, Norway. Subjects: Thirty-nine pairs of 6-month-old children and their parents in the intervention group and 20 pairs in the control group. Results: At age 15 months, the intervention group had lower intakes of ready-made porridge (2.0 vs. 5.8 servings per week (p < 0.05)), lower intake of canned baby food (2.9 vs. 6.3 servings per week (p < 0.05)) and…
VDBP, CYP27B1, and 25-Hydroxyvitamin D Gene Polymorphism Analyses in a Group of Sicilian Multiple Sclerosis Patients
2016
Multiple sclerosis (MS) is a chronic demyelinating disease of central nervous system regarded as one of the most common causes of neurological disability in young adults. The exact etiology of MS is not yet known, although epidemiological data indicate that both genetic susceptibility and environmental exposure are involved. A poor vitamin D status has been proposed as the most attractive environmental factor. Several evidence have highlighted the importance of mutations in vitamin D-regulating genes for vitamin D status. The purpose of our study was to assess the genetic variants of VDBP and CYP27B1 in MS patients and in a control group. A total of 192 subjects, including 100 MS patients a…
Vitamin D and Genetic Susceptibility to Multiple Sclerosis.
2019
Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system (CNS), resulting from the interaction among genetic, epigenetic, and environmental factors. Vitamin D is a secosteroid, and its circulating levels are influenced by environment and genetics. In the last decades, research data on the association between MS and vitamin D status led to hypothesize a possible role for hypovitaminosis D as a risk factor for MS. Some gene variants encoding proteins involved in vitamin D metabolism, transport, and function, which are responsible for vitamin D status alterations, have been related to MS susceptibility. This review explores the current literature on the influence o…
Vitamin D receptor gene ApaI and FokI polymorphisms and its association with inflammation and oxidative stress in vitamin D sufficient Caucasian Span…
2021
Background Vitamin D has gone from being just one vitamin to being an important prohormone with multiple effects on different tissue types. The mechanism of action of the active form or calcitriol is mediated by the intracellular vitamin D receptor (VDR). The interaction of the VDR with calcitriol modulates the expression of target genes involved in cell proliferation and cytokine production. Several studies have explored the effects of vitamin D deficiency in inflammatory disorders. Furthermore, some mutations in the VDR can affect its functionality. The focus of this study was to explore associations between VDR single nucleotide polymorphisms (SNPs) and markers of inflammation and oxidat…
Long-term vitamin D treatment decreases human uterine leiomyoma size in a xenograft animal model
2019
Objective To study the effects of short- and long-term vitamin D treatment on uterine leiomyomas in vivo through cell proliferation, extracellular matrix (ECM) degradation, and apoptosis. Design Preclinical study of human leiomyoma treatment with vitamin D in an nonhuman animal model. Setting Hospital and university laboratories. Patient(s)/Animal(s) Human leiomyomas were collected from patients and implanted in ovariectomized NOD-SCID mice. Intervention(s) Mice were treated with vitamin D (0.5 μg/kg/d or 1 μg/kg/d) or vehicle for 21 or 60 days. Main Outcome Measure(s) Vitamin D effect in xenograft tissue was assessed by monitoring tumor size (18F-FDG positron-emission tomography/computeriz…
Vitamin D and Cardiovascular Health
2021
The principal source of vitamin D in humans is its biosynthesis in the skin through a chemical reaction dependent on sun exposure. In lesser amounts, the vitamin can be obtained from the diet, mostly from fatty fish, fish liver oil and mushrooms. Individuals with vitamin D deficiency, defined as a serum level of 25 hydroxyvitamin D < 20 ng/dl, should be supplemented. Vitamin D deficiency is a prevalent global problem caused mainly by low exposure to sunlight. The main role of 1,25 dihydroxyvitamin D is the maintenance of calcium and phosphorus homeostasis. However, vitamin D receptors are found in most human cells and tissues, indicating many extra-skeletal effects of the vitamin, particula…