Evidence that vitamin D3 promotes mast cell–dependent reduction of chronic UVB-induced skin pathology in mice

Mast cell production of interleukin-10 (IL-10) can limit the skin pathology induced by chronic low-dose ultraviolet (UV)-B irradiation. Although the mechanism that promotes mast cell IL-10 production in this setting is unknown, exposure of the skin to UVB irradiation induces increased production of the immune modifying agent 1α,25-dihydroxyvitamin D3 (1α,25[OH]2D3). We now show that 1α,25(OH)2D3 can up-regulate IL-10 mRNA expression and induce IL-10 secretion in mouse mast cells in vitro. To investigate the roles of 1α,25(OH)2D3 and mast cell vitamin D receptor (VDR) expression in chronically UVB-irradiated skin in vivo, we engrafted the skin of genetically mast cell–deficient WBB6F1-KitW/W-v mice with bone marrow–derived cultured mast cells derived from C57BL/6 wild-type or VDR−/− mice. Optimal mast cell–dependent suppression of the inflammation, local production of proinflammatory cytokines, epidermal hyperplasia, and epidermal ulceration associated with chronic UVB irradiation of the skin in KitW/W-v mice required expression of VDR by the adoptively transferred mast cells. Our findings suggest that 1α,25(OH)2D3/VDR-dependent induction of IL-10 production by cutaneous mast cells can contribute to the mast cell’s ability to suppress inflammation and skin pathology at sites of chronic UVB irradiation

Bone marrow cell trafficking following intravenous administration

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75122/1/j.1365-2141.1999.01779.x.pd

Analytical characterization of semi-volatile organic material in coal and coal-related products.

The characterization of the semi-volatile organic content of coal and several N-methyl-2-pyrrolidinone (NMP) soluble coal extracts has been investigated using several analytical techniques, including gas chromatography mass spectrometry (GC/MS), Thermal Extraction (TE) GC/MS, Gel Permeation Chromatography (GPC), High Performance Liquid Chromatography (HPLC), Thermabeam LC/MS, Diffuse Reflectance FTIR (DRIFT), and Thermogravimetric (TGA) FTIR. Ultrasonic extraction was shown to be quicker than the traditional Soxhlet extraction technique as the first step in a solvent dissolution scheme for coal. The fractions resulting from the two techniques are similar based on characterization results obtained from HPLC, GPC, and TE-GC/MS experiments. TE-GC/MS was used to quantify the amount of NMP retained in several NMP-soluble coal extracts. The retained NMP ranged from 0.71% to 4.61% by weight. The limit of quantification was 0.015 {dollar}\\mu{dollar}g NMP. Six NMP-related compounds were identified in the NMP-soluble coal extracts that were not identified in the whole coals. TGA, TGA-FTIR, DRIFT, and TE-GC/MS were used to determine that activated carbon is a more suitable matrix for TE-GC/MS analysis of NMP than aluminum oxide, silica gel, or methanol. Thermabeam LC/MS was used to confirm that NMP-related compounds were thermal breakdown products of NMP heated in the presence of air. It was determined that these NMP-related compounds originated from either, (1) air present in the extraction vessel, or (2) reactions occurring between the whole coals and the NMP at the elevated temperatures used for the extraction. The combination of ultrasonic agitation with methanol and extended vacuum drying was successful for removal of the retained NMP from a NMP-soluble coal extract. Extrography was used to separate the NMP-soluble coal extracts into fractions based upon functionality, and the fractions were examined using DRIFT. The volatility of the fractions at 300{dollar}\\sp\\circ{dollar}C and at 800{dollar}\\sp\\circ{dollar}C, and the relative weight distributions of the fractions followed theoretical expectations. These analytical characterization techniques were successful in providing information which can be used to determine the final end-use of several NMP-soluble coal extracts