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Increased mortality of adult chronic hemodialysis (HD) patients is associated with coronary calcifications (CC), increased serum phosphorus (P), use of calcium (Ca)containing P-binders, and vitamin D deficiency. Serum concentration of fibroblast growth factor 23 (FGF 23) is markedly elevated in adults receiving dialysis and is independently associated with increased mortality. Although coronary calcifications have been described in pediatric and adult HD patients, no significant association between serum FGF 23 and CC has been reported. In our study, 5/16 patients had CC. Patients with CC were older, had longer dialysis vintage and higher serum P. Serum Ca, total PTH, elemental Ca intake, and calcitriol doses were not different for CC patients. Serum FGF 23 levels were markedly elevated in all patients (mean 4,024, range 874-8,253), but significantly higher in patients with CC (4,247 ± 10,35 vs 2,427 ± 11,92, p=0.01) and positively correlated with Agatston calcification score (r= 0.69, p=0.003) and serum P (r=0.49, p=0.05). Using multivariate analysis, serum FGF 23 and serum P remained the most significant factors associated with Agatston score. This study confirms the occurrence of CC in pediatric HD patients and is the first to show a significant association between CC and elevated serum FGF 23 in children. Keywords Pediatric * Hemodialysis * Fibroblast growth factor * Coronary calcification, Introduction Young adults with end-stage renal disease (ESRD) since childhood exhibit cardiovascular mortality 100 times greater than age-matched healthy young adults in the general population [1]. Traditional cardiovascular risk factors [...]

Vitamin D has cardiovascular protective effects besides regulating calcium homeostasis. To examine the chronic in vivo effect of a physiological dose of 1,25-dihydroxyvitamin [D.sub.3] on the occurrence of endothelium-dependent contractions, spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) were treated with the vitamin D derivative for 6 wk. The serum 1,25-dihydroxyvitamin [D.sub.3] level of both treated WKY and SHR was significantly nigher than in untreated rats while the mean arterial blood pressure of the treated SHR was significantly lower than that of control SHR. Aortic rings with or without endothelium were studied in conventional organ chambers for isometric force measurement. Confocal microscopy was used to measure the cytosolic free calcium concentration (with the fluorescent dye fluo 4) and reactive oxygen species (ROS; with dichlorodihydrofluorescein diacetate). Reverse transcription PCR and Western blotting were used to determine the mRNA and protein expression level of cyclooxygenase-1 (COX-1), prostacyclin synthase, and thromboxane synthase. The endothelium-dependent concentration-contraction curves to both acetylcholine- and A-23187-induced contractions were shifted to the right in aortas from treated SHR but not from treated WKY. The chronic treatment normalized the relaxations of contracted preparations to acetylcholine. There were no significant differences in the increases in cytosolic free calcium concentration evoked by acetylcholine and A-23187 between control and treated groups. The endothelial ROS level was higher in SHR than WKY aortas and reduced by the chronic treatment. The gene and protein expression studies indicated that the overexpression of COX-1 observed in SHR aorta was reduced by the chronic treatment. These results demonstrate that chronic treatment with 1,25-dihydroxyvitamin [D.sub.3] modulates vascular tone and this modulation is accompanied by a lowered blood pressure, reduced expression of COX-1 mRNA and protein, and reduced ROS level in SHR. The reduction in endothelium-dependent contractions does not involve the surge in endothelial cytosolic calcium concentration that initiates the contractions. 1,25-dihydroxyvitamin [D.sub.3]; endothelium-derived contracting factors; cyclooxgenase-1; reactive oxygen species doi: 10.1152/ajpheart.00288.2010.

ABSTRACT Psoriasis affects more than 5 million adults in the United States (U.S.), causing significant impairments in quality of life and incurring substantial costs in treatment. The disease is characterized [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jada.2005.12.009 Byline: Barbara L. Mark, Jo Ann S. Carson Abstract: Recent studies and commentaries link vitamin D with several autoimmune diseases, including multiple sclerosis (MS). Adequate vitamin D intake reduces inflammatory cytokines through control of gene expression, thus inadequate vitamin D intake is suggested as a mechanism that could contribute to inflammation and, consequently, development of MS. Poor vitamin D status has been associated with increased risk for development of MS, and patients with MS may suffer consequences of vitamin D deficiency, such as bone loss. Animal studies and very limited human data suggest possible benefit from vitamin D supplementation in patients with MS. Based on the current state of research, a key principle for practicing dietetics professionals is to include vitamin D status in nutritional assessment. For those at risk for poor vitamin D status, intake can be enhanced by food-based advice and, when indicated, vitamin D supplementation.

The efficacy of calcium with vitamin D supplementation for preventing hip and other fractures in healthy` postmenopausal women is examined. Amongst the healthy postmenopausal women, calcium with vitamin D supplementation resulted in a small but significant improvement in hip bone density, did not significantly reduce hip fracture and increased risk of kidney stones.

Concerns about vitamin D status in the United States have resurfaced due to increasing reports of insufficiency and deficiency. Few foods contain vitamin D naturally, and currently few foods are fortified in the United States. Intakes of vitamin D in the United States from food and food plus supplements by age, sex, and race/ethnicity group were estimated. Individuals [greater than or equal to] 1 y old who participated in the 1999-2000 National Health and Nutrition Examination Survey (NHANES 1999-2000) were included in the analysis. Vitamin D intake by non-Hispanic (NH) white, NH black, Mexican American, and all individuals in the United States was estimated and compared with recommended levels. Vitamin D intakes were highest among children and teenagers, and lowest in the oldest age categories. Among children age 1-8 y, adequate intake (AI) levels for vitamin D from food were met or exceeded by 69% of Mexican American, 59% of NH white, and 48% of NH black subpopulations. Among adults [greater than or equal to] 51 y old, only 4% met or exceeded the Al from food alone. Few women 19-50 y old or men and women [greater than or equal to] 51 y old were estimated to consume recommended vitamin D levels from food. Mean dietary intakes of vitamin D from food plus supplements were consistently highest among NH white populations, although only small proportions of all those [greater than or equal to] 51 y old had intakes above the recommended levels. The large discrepancy between vitamin D intake by older individuals from food plus supplements and recommended levels, especially for NH black and Mexican American adults, warrants intervention. KEY WORDS: * vitamin D intake * ethnic groups

Byline: John Cunningham (1) Keywords: Vitamin D; Non-calcaemic analogues; Chronic kidney disease Abstract: Vitamin D therapy for patients with chronic kidney disease has until recently comprised alfacalcidol or calcitriol, both of which effectively attenuate secondary hyperparathyroidism and the target organ consequences thereof. Unfortunately, both these agents also have significant calcaemic and phosphataemic actions leading to frequent episodes of hypercalcaemia, hyperphosphataemia and an increase in the CaxP product. It is likely that these in turn have adverse effects on cardiovascular and survival outcomes by promoting soft tissue and vascular calcification. These drawbacks have fuelled a search for vitamin D compounds with a wider therapeutic window. Experimentally, some of these have exhibited remarkable dissociation between their ability to suppress parathyroid hormone (PTH) and concomitant calcaemic actions. In the case of 22-oxacalcitriol, the calcaemic potency relative to parathyroid suppression is 100th of that of calcitriol. 22-oxacalcitriol, with paricalcitol and doxercalciferol, are now widely used. Clinical studies of these agents, while confirming efficacy that is at least as good as alfacalcidol/calcitriol, have not consistently shown benefit in head to head comparison. Experience with these agents in the paediatric arena is very limited. One placebo-controlled study has now been completed in children--paricalcitol appeared effective and well tolerated. Calcimimetics, which simultaneously lower PTH, calcium and the CaxP product are about to enter the clinical arena--early studies in adults look promising, although they will need careful evaluation in children. These two therapies are likely to be additive and will probably complement one another effectively. Author Affiliation: (1) Department of Nephrology, The Middlesex Hospital, University College London Hospitals, Mortimer Street, London W1N 8AA, UK Article History: Registration Date: 26/03/2004 Received Date: 09/01/2004 Accepted Date: 22/03/2004 Online Date: 13/05/2004