Home About us Contact
|
Home About us Contact | ||
|
|
||
Skeletal Health (skeletal + health)
Selected AbstractsToward an Expanded Understanding of the Role of the Periosteum in Skeletal Health,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2003Eric S Orwoll MD First page of article [source] Skeletal health: primate model of postmenopausal osteoporosisAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2009S.Y. Smith Abstract Currently, the nonhuman primate is the most widely used large animal model to evaluate the safety and efficacy of new drug entities to treat or prevent estrogen-deficiency-induced bone loss and osteoporosis. Surgical ovariectomy (OVX) induces a state of high bone turnover and rapid bone loss establishing a new steady-state bone mass within 8,9 months. Many systems in the monkey are similar to humans, including skeletal and reproductive physiology and the immune system, making this a plausible model suitable to evaluate the effects of new bone drugs. The long-term sequelae following OVX and withdrawal of monthly exposure to cyclic reproductive hormones in older female monkeys (cynomolgus and rhesus) mimics estrogen depletion and postmenopausal bone loss occurring in women. Characterization of the primate model revealed an apparent limitation to the extent of bone loss. Animals lose bone mass after OVX, but the extent of the bone loss cannot be described as osteoporotic. The small differences between OVX and sham-operated controls in many important bone measurements is overcome by including 15,20 animals per group to provide adequate statistical power. The long-term, at least 16 month, bone safety studies performed to satisfy regulatory guidelines provide an opportunity to study treatment effects for an extended period not covered in shorter-term safety studies. In vivo end-points such as densitometry and biochemical markers translate easily to clinical use, while biomechanical end-points that cannot be measured clinically can be used to predict fracture prevention. To date, the monkey OVX model has been used to support submissions for many new drugs including anabolics, bisphosphonates and selective estrogen receptor modulators. Despite its limitations, the OVX monkey model remains the best characterized of the large animal models of osteopenia and has become integral to osteoporosis drug development. Am. J. Primatol. 71:752,765, 2009. © 2009 Wiley-Liss, Inc. [source] IBD and skeletal health: Children are not small adults!INFLAMMATORY BOWEL DISEASES, Issue 11 2005Francisco A Sylvester MD Abstract Patients with inflammatory bowel disease often have decreased bone mass, and fragility fractures can occur. Multiple disease- and treatment related factors, including malnutrition, inflammation, malabsorption, decreased weight-bearing physical activity, and corticosteroids negatively influence bone metabolic activity. Because low-impact fracture is the pathologic expression of critically reduced bone mass and bone quality, knowing the relative risk of fractures in patients with IBD is of great interest. The absolute risk for incident fractures in these patients is still being debated. Clinical and laboratory research is clarifying mechanisms by which IBD can affect the function of osteoblasts and osteoclasts. In this concise review, we aim to provide an update on this topic, with focus on how pediatric IBD affects bone health. [source] The European Male Ageing Study (EMAS): design, methods and recruitmentINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2009David M. Lee Summary Life expectancy is increasing in most developed countries, in part due to improved socioeconomic conditions and in part to advances in healthcare. It is widely acknowledged that the promotion of healthy ageing by delaying, minimizing or preventing disabilities or diseases is one of the most important public health objectives in this century. In contrast to the menopausal transition in females, we know relatively little about the contribution of androgens and anabolic hormones to the quality of ageing in men. The European Male Ageing Study (EMAS) is a multicentre prospective cohort designed to examine the prevalence, incidence and geographical distribution of gender-specific and general symptoms of ageing in men, including their endocrine, genetic and psychosocial predictors. Men aged 40,79 years were recruited from eight European centres: Florence (Italy), Leuven (Belgium), Lodz (Poland), Malmö (Sweden), Manchester (UK), Santiago de Compostela (Spain), Szeged (Hungary) and Tartu (Estonia). Subjects were recruited from population registers and those who agreed to take part completed a detailed questionnaire including aspects of personal and medical history, lifestyle factors and sexual function. Objective measures of body size, cognition, vision, skeletal health and neuromuscular function were obtained. Blood and DNA specimens were collected for a range of biochemical and genetic analyses. After an average of 4 years, it is planned to resurvey the participants with similar assessments. A total of 3369 men with a mean age of 60 ± 11 years were recruited. The mean centre response rate was 43%, and highest in those aged 50,59 years. Those who participated were marginally younger than those who were invited but declined to participate (60.0 vs. 61.1 years). Participants left education slightly later than a sample of non-participants, though there were no consistent differences in levels of general health, physical activity, or smoking. EMAS will provide new population-based data concerning the main features that characterize ageing in men and its critical determinants, particularly with reference to age-related changes in hormone levels. Such information is an important prerequisite to develop effective strategies to reduce age-related disabilities and optimise health and well-being into old-age. [source] Bone mineralization defects and vitamin D deficiency: Histomorphometric analysis of iliac crest bone biopsies and circulating 25-hydroxyvitamin D in 675,patientsJOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2010Matthias Priemel Abstract Parathyroid hormone (PTH) is only one measurable index of skeletal health, and we reasoned that a histomorphometric analysis of iliac crest biopsies would be another and even more direct approach to assess bone health and address the required minimum 25-Hydroxyvitamin D [25(OH)D] level. A cohort from the northern European population with its known high prevalence of vitamin D deficiency therefore would be ideal to answer the latter question. We examined 675 iliac crest biopsies from male and female individuals, excluding all patients who showed any signs of secondary bone diseases at autopsy. Structural histomorphometric parameters, including osteoid indices, were quantified using the Osteomeasure System according to ASBMR standards, and serum 25(OH)D levels were measured for all patients. Statistical analysis was performed by Student's t test. The histologic results demonstrate an unexpected high prevalence of mineralization defects, that is, a pathologic increase in osteoid. Indeed, 36.15% of the analyzed patients presented with an osteoid surface per bone surface (OS/BS) of more than 20%. Based on the most conservative threshold that defines osteomalacia at the histomorphometric level with a pathologic increase in osteoid volume per bone volume (OV/BV) greater than 2% manifest mineralization defects were present in 25.63% of the patients. The latter were found independent of bone volume per trabecular volume (BV/TV) throughout all ages and affected both sexes equally. While we could not establish a minimum 25(OH)D level that was inevitably associated with mineralization defects, we did not find pathologic accumulation of osteoid in any patient with circulating 25(OH)D above 75,nmol/L. Our data demonstrate that pathologic mineralization defects of bone occur in patients with a serum 25(OH)D below 75,nmol/L and strongly argue that in conjunction with a sufficient calcium intake, the dose of vitamin D supplementation should ensure that circulating levels of 25(OH)D reach this minimum threshold (75,nmol/L or 30,ng/mL) to maintain skeletal health. © 2010 American Society for Bone and Mineral Research [source] Endogenous Estrogen Levels and the Effects of Ultra-Low-Dose Transdermal Estradiol Therapy on Bone Turnover and BMD in Postmenopausal Women,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 11 2007Alison J Huang Abstract In a randomized controlled trial of a 0.014 mg/d transdermal estradiol patch, serum bone turnover markers decreased to a greater degree in postmenopausal women with lower versus higher endogenous estradiol levels. This suggests that the protective effects of ultra-low-dose estrogen therapy on the postmenopausal skeletal health may depend critically on women's endogenous estrogen levels before treatment. Introduction: Postmenopausal women with very low or undetectable estradiol levels have lower BMD, increased bone turnover, and increased risk of hip and vertebral fracture. We assessed whether the effects of ultra-low-dose 0.014 mg/d transdermal estradiol (Menostar; Berlex, Montvale, NJ, USA) on bone turnover and BMD are influenced by endogenous estradiol levels. Materials and Methods: We analyzed data from postmenopausal women (mean age, 66 yr) randomized to an 0.014-mg/d transdermal estradiol patch or placebo in the ultra-low-dose transdermal estrogen (ULTRA) trial. The free estradiol index (FEI), calculated as the ratio of total estradiol (by mass spectometry) to sex hormone-binding globulin (SHBG; by immunoradiometric assay) × 100, was used to estimate bioavailable estradiol at baseline. Among the 382 women who adhered to ,80% of study medication, we examined change in serum osteocalcin and bone-specific alkaline phosphatase levels at 12 mo and total hip and lumbar spine BMD at 24 mo in each quintile of FEI. Results: Compared with women in the highest quintile of FEI, those in the lowest quintile of FEI had a 26% greater reduction in bone-specific alkaline phosphatase and 15% greater reduction in osteocalcin in response to ultra-low estradiol treatment (p for trend across quintiles < 0.05). There was a trend toward greater improvement in total hip BMD (p = 0.06) but not spine BMD (p = 0.90) in those with lower versus higher FEI levels. Conclusions: The beneficial effects of ultra-low-dose 0.014-mg/d transdermal estrogen therapy on skeletal health may depend critically on women's endogenous estrogen levels before treatment. [source] Retinol Intake and Bone Mineral Density in the Elderly: The Rancho Bernardo Study,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2002Joanne H. E. Promislow Abstract Retinol is involved in bone remodeling, and excessive intake has been linked to bone demineralization, yet its role in osteoporosis has received little evaluation. We studied the associations of retinol intake with bone mineral density (BMD) and bone maintenance in an ambulatory community-dwelling cohort of 570 women and 388 men, aged 55,92 years at baseline. Regression analyses, adjusted for standard osteoporosis covariates, showed an inverse U-shaped association of retinol, assessed by food-frequency questionnaires in 1988,1992, with baseline BMD, BMD measured 4 years later, and BMD change. Supplemental retinol use, reported by 50% of women and 39% of men, was an effect modifier in women; the associations of log retinol with BMD and BMD change were negative for supplement users and positive for nonusers at the hip, femoral neck, and spine. At the femoral neck, for every unit increase in log retinol intake, supplement users had 0.02 g/cm2 (p = 0.02) lower BMD and 0.23% (p = 0.05) greater annual bone loss, and nonusers had 0.02 g/cm2 (p = 0.04) greater BMD and 0.22% (p = 0.19) greater bone retention. However, among supplement users, retinol from dietary and supplement sources had similar associations with BMD, suggesting total intake is more important than source. In both sexes, increasing retinol became negatively associated with skeletal health at intakes not far beyond the recommended daily allowance (RDA), intakes reached predominately by supplement users. This study suggests there is a delicate balance between ensuring that the elderly consume sufficient vitamin A and simultaneously cautioning against excessive retinol supplementation. [source] Paediatric obesity, physical activity and the musculoskeletal systemOBESITY REVIEWS, Issue 5 2009S. P. Shultz Summary The current epidemic of paediatric obesity is consistent with a myriad of health-related comorbid conditions. Despite the higher prevalence of orthopaedic conditions in overweight children, a paucity of published research has considered the influence of these conditions on the ability to undertake physical activity. As physical activity participation is directly related to improvements in physical fitness, skeletal health and metabolic conditions, higher levels of physical activity are encouraged, and exercise is commonly prescribed in the treatment and management of childhood obesity. However, research has not correlated orthopaedic conditions, including the increased joint pain and discomfort that is commonly reported by overweight children, with decreases in physical activity. Research has confirmed that overweight children typically display a slower, more tentative walking pattern with increased forces to the hip, knee and ankle during ,normal' gait. This research, combined with anthropometric data indicating a higher prevalence of musculoskeletal malalignment in overweight children, suggests that such individuals are poorly equipped to undertake certain forms of physical activity. Concomitant increases in obesity and decreases in physical activity level strongly support the need to better understand the musculoskeletal factors associated with the performance of motor tasks by overweight and obese children. [source] Protective action of aqueous black tea (Camellia sinensis) extract (BTE) against ovariectomy-induced oxidative stress of mononuclear cells and its associated progression of bone lossPHYTOTHERAPY RESEARCH, Issue 9 2009Asankur Sekhar Das Abstract The protective action of aqueous black tea extract (BTE) against ovariectomy-induced oxidative stress of mononuclear cells and its associated progression of bone loss was demonstrated in this study. Eighteen female adult 6-month-old Wistar albino rats were divided into three groups: sham-control (A), bilaterally ovariectomized (B) and bilaterally ovariectomized + BTE supplemented (C). Studies included the measurement of oxidative (nitric oxide, lipid peroxidation) and antioxidative (superoxide dismutase, catalase) markers, inflammatory cytokines (IL-6, TNF- ,), osteoclast differentiation factor (RANKL) and bone resorption markers (tartrate-resistant acid phosphatase and hydroxyproline). Also quantitative histomorphometry and histological studies were undertaken. The bone breaking force was measured. The results indicate that BTE was effective in preserving and restoring skeletal health by reducing the number of active osteoclasts. Such changes with BTE supplementation were steadily linked with the reduced oxidative stress of mononuclear cells, serum levels of bone resorbing cytokines, osteoclast differentiation factor and resorption markers. The results of the bone breaking force, histological and histomorphometric analyses further supported the hypothesis. This study suggests that BTE has both protective and restorative actions against ovariectomy-induced mononuclear cell oxidative stress and associated bone loss. Copyright © 2009 John Wiley & Sons, Ltd. [source] Association of 25-hydroxyvitamin D with prevalent osteoarthritis of the hip in elderly men: The osteoporotic fractures in men studyARTHRITIS & RHEUMATISM, Issue 2 2010R. K. Chaganti Objective To examine the cross-sectional association of serum levels of 25-hydroxyvitamin D, or 25(OH)D, with prevalent radiographic hip osteoarthritis (OA) in elderly men. Methods In a cohort of 1,104 elderly men from the Osteoporotic Fractures in Men Study, 25(OH)D serum levels were determined by mass spectrometry, followed by pelvic radiographs ,4.6 years later. Categories of vitamin D levels were defined as follows: deficiency as ,15 ng/ml, insufficiency as 15.1,30 ng/ml, and sufficiency as >30 ng/ml. Radiographs were assessed for severity of hip OA using a summary grade of 0,4 for individual features of hip OA. Logistic regression was used to assess associations of serum 25(OH)D levels with prevalent radiographic hip OA; covariates included age, clinic site, season at the time of blood withdrawal, self-reported hip pain for >30 days, timed 6-meter walk, presence of at least 1 coexisting condition, and self-rated health status. Results Men with radiographic hip OA had a slower 6-meter walking time (P < 0.0001), reported more hip pain (P = 0.0001), had a lower vitamin D level (P = 0.0002), and had a higher prevalence of vitamin D insufficiency (P = 0.002) and vitamin D deficiency (P = 0.012) compared with controls. Higher 25(OH)D levels were associated with a lower prevalence of radiographic hip OA (odds ratio [OR] 1.39 per 1 SD decrease in 25[OH]D, 95% confidence interval [95% CI] 1.11,1.74) after adjusting for age, season, and clinic site. Men with vitamin D insufficiency had an increased likelihood of prevalent radiographic hip OA (OR 2.19, 95% CI 1.21,3.97) compared with men with sufficient levels of 25(OH)D, and in men with vitamin D deficiency, there was a tendency toward an increased likelihood of radiographic hip OA (OR 1.99, 95% CI 0.83,4.74). Conclusion Men with vitamin D deficiencies are twice as likely to have prevalent radiographic hip OA, and therefore vitamin D therapy to augment skeletal health in the elderly is warranted. [source] Preserving bone health in patients with hormone-sensitive prostate cancer: the role of bisphosphonatesBJU INTERNATIONAL, Issue 11 2009Fred Saad Men with prostate cancer initiating androgen-deprivation therapy (ADT) may have multiple factors that threaten their skeletal health, including increased fracture risk from bone loss during ADT and the propensity to develop bone metastases, which may lead to skeletal-related events (SREs). Bisphosphonates have utility in oncology for patients with bone metastases to prevent bone loss during hormonal therapy and in the benign setting to treat osteoporosis. These agents have an emerging role in patients with hormone-sensitive prostate cancer (HSPC). Etidronate, alendronate, pamidronate, and zoledronic acid have all shown efficacy in preventing ADT-related bone loss. Alendronate and zoledronic acid have also been shown to increase bone mineral density vs baseline during ADT. Patients with bone metastases from HSPC who received 4 mg zoledronic acid every 3 or 4 weeks had a low incidence of skeletal complications, although controlled study data have not been reported. Bisphosphonate treatment in men with HSPC may be effective for the prevention of ADT-related bone loss, underscoring the importance of treating early to avoid SREs and potentially delay disease progression to metastatic bone disease. [source] Total phalloplasty using a musculocutaneous latissimus dorsi flapBJU INTERNATIONAL, Issue 4 2007Sava V. Perovic Authors from Serbia describe their experience of total phalloplasty in children and adults using a musculocutaneous latissimus dorsi free flap, finding that this method successfully allowed the creation of a neophallus, facilitating subsequent urethroplasty and the safe insertion of a penile prosthesis. In the second article in this section, authors from Finland present the findings in 54 patients relating to skeletal health after intestinal bladder augmentation. OBJECTIVE To present total phalloplasty in children and adults using a musculocutaneous latissimus dorsi (MLD) free flap to create a large neophallus, that allows easy urethroplasty and implantation of a prosthesis. PATIENTS AND METHODS From April 1999 to January 2006, 16 patients (mean age 24 years, range 10,34) had a total phalloplasty; the indications were congenital anomalies of the penis in 12, iatrogenic in two and accidental penile trauma in two. The MLD flap is mobilized on a subscapular artery and vein, and a thoracodorsal nerve. The neophallus is created on-site and after dividing the neurovascular pedicle, transferred to the pubic region, where it is anastomosed with the femoral artery, saphenous vein and ilio-inguinal nerve. The donor site was closed directly in 15 patients while in one a split-thickness skin graft was used to cover the defect. In the following stages, two- or three-stage buccal mucosa urethroplasty was used in 11 patients; a penile prosthesis was implanted in seven. RESULTS The mean (range) follow-up was 31 (12,74) months; the penis was 14,18 cm long and 11,15 cm in circumference. There was no partial or total flap necrosis; the donor site healed satisfactorily in 13 patients while in the remaining three there was moderate scarring. The patency of the urethra was good in all patients. Two urethrocutaneous fistulae developed; one closed spontaneously and the other was successfully treated with minor surgery. The function of the implanted penile prostheses was satisfactory in all patients. CONCLUSIONS The MLD flap allows the creation of a neophallus of good size and with a good aesthetic appearance; it allows urethroplasty and safe implantation of a penile prosthesis, and it can also be used in children. [source] | ||||||||||