Bone Abstracts

Calcium and vitamin D are essential components for bone health, thus calcium and vitamin D supplementation is an important strategy in the management of osteoporosis.However, the benefit of calcium and vitamin D supplementation on bone health is still controversial. Moreover, potentially harmful effects of excessive calcium supplementation on cardiovascular health are recently suggested. Too high a level of vitamin D has been also reported to have severa...

Vitamin D deficiency has been reported in adult patients with autoimmune diseases including rheumatoid arthritis, however, the data in patients with juvenile idiopathic arthritis (JIA) are inconsistent. The aim of the study was to assess serum 25-hydroxyvitamin D (25(OH) D in children and adolescents with JIA, and to determine potential risk factors for vitamin D deficiency.In this cross-sectional study, we evaluated 189 patients with JIA (113 girls, 76 ...

Objectives: Vitamin D is an essential hormone for growth and development of bones in children. Prevalence of vitamin D deficiency is remarkable during childhood and adolescence throughout the world. The aim of this study was to specify the optimal dose of vitamin D in growing girls during an academic year in a sunny city.Materials and methods: This randomized clinical trial study was carried out in Yazd in the Center of Iran in 2007; 120 junior high scho...

The relationship between vitamin D status and lean mass accretion in young children is not well understood.Objective: To explore vitamin D status in relation to lean mass outcomes over 12 mo in children 2–8 years.Methods: This was a secondary analysis of trial data (clinicaltrials.gov: NCT02097160, NCT02387892) in Montreal, Canada. Children consumed their normal vitamin D intake for 6 mo (Apr–Oct 2014, n=39) and ...

Background: It is well established that Asians have lower levels of vitamin D (25OHD) when compared to Caucasians. Vitamin D binding protein (DBP) levels are also lower in some races than in Caucasians.Objectives: i) To find out whether DBP is lower in Asians; ii) To find out whether free 25OHD is lower in Asians; iii) To find out whether PTH is increased in Asians and interpret this in relation to 25OHD levels and iv) To find out whether the increment i...

Biographical DetailsDr Leanne M Ward is an Associate Professor of Pediatrics at the University of Ottawa where she holds a Research Chair in Pediatric Bone Health. She is the Medical Director of the Pediatric Bone Health Clinical and Research Programs at the Children’s Hospital of Eastern Ontario (CHEO) and a pediatric endocrinologist within the Division of Endocrinology and Metaboli...

Background: There have been many studies on the association between vitamin D and testosterone in the world. But it has not been fully clarified. Furthermore, data in Korean men is limited. This study aimed to determine the association between vitamin D and testosterone levels in korean men.Methods: This cross sectional study analyzed serum 25-hydroxyvitamin D (25(OH)D) and total testosterone in 365 Korean men over 25 years of age who visited a local uni...

Pseudovitamin D-deficiency rickets (PDDR) is a rare autosomal recessive disorder resulting from a defect in renal 25-hydroxyvitamin D 1α-hydroxylase, which is encoded by the CYP27B1 gene. To our best knowledge, 48 mutations of the CYP27B1 gene have been identified so far. In the present study, we investigated CYP27B1 mutations in seven individuals from six separate families and identified nine different mutations: two novel missense mutations (G194R, R259L), three novel a...

Backround: Vitamin D dependent rickets type 1 (VDDR-1) is an autosomal recessive disorder caused by 1a hydroxylase enzyme deficiency, that leads to low or undetectable levels of 1,25 dihydroxyvitamin D despite normal levels of 25-hydroxyvitamin D levels. Additional laboratory findings include hypocalcemia and increased levels of parathyroid hormone. Clinically, it presents as early onset rickets and severe hypotonia.Presenting problem: A 6-year-old Cauca...

Objectives: Children during the intensive treatment of cancer might be exposed to vitamin D deficiency and consequently leads to, among other things, bone deficits and low bone mass. The aim of this study was: i) to assess the serum concentration of 25-hydroxyvitamin D (25-OH-D) in children diagnosed with acute lymphoblastic leukemia (ALL) at two time points (time of diagnosis and just after induction treatment), ii) to evaluate the impact of used drugs on the changes of 25-OH...