Vitamin D3-3 beta-sulfate has been synthesized using pyridine sulfur trioxide as the sulfate donor. It has been shown to be pure by high performance liquid chromatography and spectral methods. Unlike previous reports, the product has been identified unambiguously as the 3 beta-sulfate ester of vitamin D3 by its ultraviolet, nuclear magnetic resonance, infrared, and mass spectra. The biological ...

CYP11A1 can hydroxylate vitamin D3 at carbons 17, 20, 22, and 23, producing a range of secosteroids which are biologically active with respect to their ability to inhibit proliferation and stimulate differentiation of various cell types, including cancer cells. As 1a-hydroxylation of the primary metabolite of CYP11A1 action, 20S-hydroxyvitamin D3 [20(OH)D3], greatly influences its properties, w...

The advance in knowledge of clinical disorders involving calcium and bone diseases has resulted in part from the development of assay procedures for the major vitamin D metabolites, but the values of the same samples measured in different laboratories vary considerably. They suggest that the chromatographic purification involved in these assays seems to be a critical step. In this study, we com...

loc-Hydroxy[6-3H]vitamin D, has been synthesized with a specific activity of 4 Ci/mmol, and its metabolism in rats has been studied. It is rapidly converted to ln,25-dihydroxy[6-3H]vitamin D, in uiuo. Following an intravenous or oral dose, a maximal concentration of loc,25-dihydroxy[6-3H]vitamin D, is found 2 and 4 hours, respectively, before the maximal intestinal calcium transport response is...

A variant of the chronic myelogenous leukemia cell line, RWLeu-4, that is resistant to the antiproliferative effects of vitamin D3 was established. Although RWLeu-4 proliferation is inhibited by 1 nmol/L vitamin D3, the resistant cells (JMRD3) continue to proliferate in the presence of 100 nmol/L vitamin D3. Both cells express similar patterns of differentiation-specific antigens after treatmen...

Aim: To prospectively evaluate the effects of vitamin D3 on disease activity and quality of life in ulcerative colitis (UC) patients with hypovitaminosis D. Methods: The study was a prospective double-blinded, randomized trial conducted at Community Regional Medical Center, Fresno, CA from 2012 2013. Patients with UC and a serum 25(OH)D level <30ng/ml were eligible for the study. Enrolled subje...