The primary aim was to study the relationship between individual serum levels of 25-hydroxyvitamin D and 4b-hydroxycholesterol, which is an endogenous biomarker of the drug-metabolizing CYP3A enzymes. In addition, the relationship between this biomarker and inflammation, measured as C-reactive protein (CRP), was investigated. Serum samples were used from a recently performed clinical trial in p...

BACKGROUND We previously demonstrated that 25-hydroxyvitamin D(3) concentrations in gingival crevicular fluid are 300 times higher than those in the plasma of patients with aggressive periodontitis. Here we explored whether 25-hydroxyvitamin D(3) can be synthesized by periodontal soft tissue cells. We also investigated which of the two main kinds of hydroxylases, CYP27A1 and CYP2R1, is the key ...

BACKGROUND Vitamin D insufficiency could be associated with the prevalence of atopic dermatitis (AD). OBJECTIVE To examine vitamin D status and the relations between serum 25-hydroxyvitamin D levels, SCORAD score, serum LL-37 level, and body mass index (BMI) in Korean AD patients, and to explore whether these associations differ between adults and children. METHODS Serum 25-hydroxyvitamin D...

Anticonvulsant therapy of seizure disorders in man is associated with the development of complications involving bone and mineral metabolism including hypocalcemia, elevated serum immunoreactive parathyroid hormone levels, and increased amounts of unmineralized bone or osteoid. The latter has been attributed to a reduction in serum-25-hydroxycholecalciferol levels resulting from increased hepat...

CONTEXT Inverse associations are reported between circulating 25-hydroxyvitamin D and visceral adiposity. The effects of vitamin D levels on atherosclerosis are unknown. OBJECTIVE The objective of this study was to test for relationships between vitamin D, adiposity, bone density, and atherosclerosis in African-Americans. DESIGN Circulating 25-hydroxyvitamin D, 1,25 dihydroxyvitamin D, inta...

A liquid chromatography tandem mass spectrometry method for 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 from human plasma has been developed. Sample preparation was fast and efficient using a Thermo ScientificTM SOLATM hydrophobic reversed phase (HRP) plate. Analysis was carried out using a Thermo ScientificTM SyncronisTM C18 1.7 μm, 50 × 2.1 mm column to give a fast separation with a cycle t...

BACKGROUND Vitamin D insufficiency is associated with proteinuria and could be a risk factor for end-stage renal disease (ESRD). However, few studies have examined the significance of vitamin D insufficiency as a contributing factor for the development of ESRD in the Asian chronic kidney disease (CKD) population. METHODS Authors examined the relationship between vitamin D status and the stagi...

BACKGROUND AND PURPOSE Vitamin D status has been associated with inflammatory activity in multiple sclerosis (MS), but it is not known if it is associated with gray matter volume, the loss of which predicts long-term disability in MS. The association of vitamin D levels with brain volume measures and inflammatory activity in patients with clinically isolated syndrome (CIS) was investigated. M...

PURPOSE To investigate associations between serum 25-hydroxyvitamin D levels and dry eye syndrome (DES), and to evaluate the differential effect of vitamin D on ocular diseases including age-related macular disease (AMD), diabetic retinopathy (DR), cataract, and DES. METHODS A total of 16,396 participants aged >19 years were randomly selected from the Korean National Health and Nutrition Exam...

The primary aim was to study the relationship between individual serum levels of 25-hydroxyvitamin D and 4β-hydroxycholesterol, which is an endogenous biomarker of the drug-metabolizing CYP3A enzymes. In addition, the relationship between this biomarker and inflammation, measured as C-reactive protein (CRP), was investigated. Serum samples were used from a recently performed clinical trial in p...