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Body BMD (body + bmd)
Kinds of Body BMD Selected Abstracts,-Arrestin2 Regulates the Differential Response of Cortical and Trabecular Bone to Intermittent PTH in Female Mice,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2005Mary L Bouxsein PhD Abstract Cytoplasmic arrestins regulate PTH signaling in vitro. We show that female ,-arrestin2,/, mice have decreased bone mass and altered bone architecture. The effects of intermittent PTH administration on bone microarchitecture differed in ,-arrestin2,/, and wildtype mice. These data indicate that arrestin-mediated regulation of intracellular signaling contributes to the differential effects of PTH at endosteal and periosteal bone surfaces. Introduction: The effects of PTH differ at endosteal and periosteal surfaces, suggesting that PTH activity in these compartments may depend on some yet unidentified mechanism(s) of regulation. The action of PTH in bone is mediated primarily by intracellular cAMP, and the cytoplasmic molecule ,-arrestin2 plays a central role in this signaling regulation. Thus, we hypothesized that arrestins would modulate the effects of PTH on bone in vivo. Materials and Methods: We used pDXA, ,CT, histomorphometry, and serum markers of bone turnover to assess the skeletal response to intermittent PTH (0, 20, 40, or 80 ,g/kg/day) in adult female mice null for ,-arrestin2 (,-arr2,/,) and wildtype (WT) littermates (7-11/group). Results and Conclusions: ,-arr2,/, mice had significantly lower total body BMD, trabecular bone volume fraction (BV/TV), and femoral cross-sectional area compared with WT. In WT females, PTH increased total body BMD, trabecular bone parameters, and cortical thickness, with a trend toward decreased midfemoral medullary area. In ,-arr2,/, mice, PTH not only improved total body BMD, trabecular bone architecture, and cortical thickness, but also dose-dependently increased femoral cross-sectional area and medullary area. Histomorphometry showed that PTH-stimulated periosteal bone formation was 2-fold higher in ,-arr2,/, compared with WT. Osteocalcin levels were significantly lower in ,-arr2,/, mice, but increased dose-dependently with PTH in both ,-arr2,/, and WT. In contrast, whereas the resorption marker TRACP5B increased dose-dependently in WT, 20-80 ,g/kg/day of PTH was equipotent with regard to stimulation of TRACP5B in ,-arr2,/,. In summary, ,-arrestin2 plays an important role in bone mass acquisition and remodeling. In estrogen-replete female mice, the ability of intermittent PTH to stimulate periosteal bone apposition and endosteal resorption is inhibited by arrestins. We therefore infer that arrestin-mediated regulation of intracellular signaling contributes to the differential effects of PTH on cancellous and cortical bone. [source] Interleukin-6 Gene Polymorphism Is Related to Bone Mineral Density During and After Puberty in Healthy White Males: A Cross-Sectional and Longitudinal StudyJOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2000Mattias Lorentzon Abstract Bone mineral density (BMD) is under strong genetic control and is the major determinant of fracture risk. The cytokine interleukin-6 (IL-6) is an important regulator of bone metabolism and is involved in mediating the effects of androgens and estrogens on bone. Recently, a G/C polymorphism in position ,174 of the IL-6 gene promoter was found. We investigated this genetic polymorphism in relation to BMD during late puberty and to peak bone mass, in healthy white males. We identified the IL-6 genotypes (GG, GC, and CC) in 90 boys, age 16.9 ± 0.3 years (mean ± SD), using polymerase chain reaction (PCR). BMD (g/cm2) at the femoral neck, lumbar spine, and total body was measured using dual energy X-ray absorptiometry. The volumetric BMD (vBMD; mg/cm3) of the lumbar spine was estimated. Differences in BMD in relation to the genotypes were calculated using analysis of variance (ANOVA). Subjects with the CC genotype had 7.9% higher BMD of the femoral neck (p = 0.03), 7.0% higher BMD of the lumbar spine (p < 0.05), and 7.6% higher vBMD of the lumbar spine (p = 0.04), compared with their GG counterparts. Using multiple regression, the IL-6 genotypes were independently related to total body BMD (CC > GG; p = 0.03), humerus BMD (CC > GG; p < 0.05), neck BMD (CC > GG; p = 0.01), spine BMD (CC > GG; p = 0.01), and spine vBMD (CC > GG; p = 0.008). At age 19.3 ± 0.7 years (mean ± SD; 88 men) the IL-6 genotypes were still independent predictors for total body BMD (CC > GG; p = 0.03), humerus BMD (CC > GG; p = 0.03), spine BMD (CC > GG; p = 0.02), and spine vBMD (CC > GG; p = 0.003), while the IL-6 genotypes were not related to the increase in bone density seen after 2 years. We have shown that polymorphism of the IL-6 gene is an independent predictor of BMD during late puberty and of peak bone mass in healthy white men. [source] Liver transplantation for progressive familial intrahepatic cholestasis: Clinical and histopathological findings, outcome and impact on growthPEDIATRIC TRANSPLANTATION, Issue 6 2007Sema Aydogdu Abstract:, In this study, we analyze the demographic features, clinical and histopathological findings in patients who underwent liver transplantation for progressive familial intrahepatic cholestasis. We also analyze outcome and impact of liver transplantation on growth and bone mineral content. Most of the patients were presented with jaundice mainly beginning within the first six months. At the time of initial admission; eight patients had short stature (height SD score <2), and four patients had weight SD score <2. Liver transplantation were performed at the age of 43.2 ± 27 months (range 9 to 96 mfonths), 6.5 ± 3.5 months later after the first admission. Infection, surgical complications and osmotic diarrhea associated with severe metabolic acidosis were noted in 41.4%, 16.6% and 33.3%, respectively. One patient developed posttransplant lymphoproliferative disorder. Overall; 1 year graft and patient survival was 69.2% and 75%, respectively. At the end of the 1st year only 2 patients had height SD score <2. Linear regression of height gain against increase in total body BMD measured at the time of transplantation and 1 year after liver transplantation gave a coefficient r = 0.588 (p = 0.074). No correlation was found between the height gain and age and PELD score at time of transplantation, and no difference was noted between the sexes and donor type. Liver transplantation is effective treatment modality with good outcome and little morbidity, and increases the growth acceleration in patients with PFIC associated with cirrhosis. [source] Risk factors for bone mineral density loss in pediatric renal transplant patientsPEDIATRIC TRANSPLANTATION, Issue 2 2000Eileen N. Ellis Abstract: Bone mineral density (BMD) is decreased in both adult and pediatric renal transplant recipients. To investigate the risk factors associated with this decrease in BMD post-renal transplant, we studied 33 children, aged 7,22 yr, who had received a renal transplant from 0.3 to 10 yr prior to this study. BMD analysis of the total body, spine, and femur was carried out by using dual-energy X-ray absorptiometry (DEXA). Age, weight, Tanner stage, time on dialysis prior to transplantation, cumulative corticosteroid dosage, and cyclosporin A (CsA) dosage since transplantation, and use of corticosteroid therapy prior to transplantation, were recorded. Spine, femur, and total body BMD Z -scores were greater than two standard deviations (2 SD) below the mean in 45%, 42%, and 17% of patients, respectively. Age correlated inversely with total body and spine BMD Z -scores (p = 0.001 and p = 0.008); no child under 14 yr of age had a total body or spine BMD Z -score greater than 2 SD below the mean for age. Patients at a Tanner stage of 4 or 5 had lower total body and spine BMD Z -scores than did patients at Tanner stages 1,3 (p = 0.043). Time post-transplant correlated inversely with both spine and total body BMD Z -score (p = 0.013 and p = 0.023). Only total body BMD Z -score correlated inversely with cumulative corticosteroid dose (in g, p = 0.045). BMD did not correlate with cumulative CsA dose. Black patients tended to have decreased total body BMD compared with Caucasian patients. In pediatric renal transplant patients, decreases in BMD start in adolescence. Risk factors for BMD loss in these patients include increasing age, time post-transplant, increasing Tanner stage, and ethnicity. Longitudinal studies in these patients and strategies to improve BMD are needed. [source] No association between inhaled corticosteroids and whole body DXA in postmenopausal women,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 7 2006Sölve Elmståhl MD Abstract Purpose Postmenopausal women treated with corticosteroids are regarded as a high-risk group due to the effect of both natural bone loss and possible adverse effects of treatment with inhaled corticosteroids (IC). Objective To compare bone mineral density (BMD) in postmenopausal women exposed only to IC (IC group, n,=,106) with that of BMD in women not exposed to corticosteroids (n,=,124) and women exposed to oral and/or intra-articular injections in addition to inhaled corticosteroids (OC group, n,=,31). The women were recruited from a population-based prospective cohort study. Methods Dual X-ray absorptiometry (DXA) technique was used to measure BMD in whole body, spine, pelvis and lower extremities. A health questionnaire and an interview about past and present medication use were used. Results The mean duration and dose of IC were 9.5,±,4.5 years and 615,µg daily. Whole body BMD did not significantly differ between the IC group (1.103,g/cm2) and the unexposed group (1.087,g/cm2). Within the IC group, BMD stratified for cumulative dose of IC, duration or current dose above or below 800,µg did not differ. Z -score BMD for tertiles did not differ when comparing the IC and OC groups. Conclusion No difference in BMD was noted between postmenopausal women exposed to inhaled corticosteroids and unexposed controls nor was there any dose response relationship between inhaled corticosteroid therapy and BMD. Copyright © 2006 John Wiley & Sons, Ltd. [source] Bone metabolism markers and ghrelin in boys at different stages of sexual maturityACTA PAEDIATRICA, Issue 5 2009Jaak Jürimäe Abstract Aim: To examine the relationship of the markers of bone formation (procollagen type I N-terminal propeptide [PINP]) and bone resorption (type I carboxyterminal telopeptide [ICTP]) with bone mineral content (BMC), bone mineral density (BMD), ghrelin and testosterone in boys during puberty. Methods: Sixty boys were divided in three groups (20 boys in each) based on the pubertal stage (G1, I; G2,G3, II; G4,G5, III). Fasting PINP, ICTP, ghrelin and testosterone were measured. Total body BMD, lumbar BMD, lumbar apparent volumetric BMD (BMAD) and BMC were measured by DXA. Results: PINP and ICTP values peaked at the beginning of puberty (Group II). Ghrelin was lower in Groups II and III compared to less mature boys. PINP and ICTP correlated with each other and were associated with lumbar BMAD in total group of boys. Relationships of PINP and ICTP with total BMD, total BMC and lumbar spine BMD in Group I were observed. PINP and ICTP were also correlated with testosterone in Group II and with lumbar spine BMAD in Group III. Conclusion: These data suggest that testosterone stimulates PINP and ICTP in early puberty, while ghrelin has no direct influence on bone turnover markers in boys at different stages of puberty. [source] | ||||||||||