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Sample records for extremity bone mass

  1. Low Bone Mass in Thalassemia

    Science.gov (United States)

    4 Low Bone Mass in Thalassemia • In addition to a diet rich in calcium and vitamin D, your doctor may recommend taking calcium and/or vitamin D ... Zoledronic acid may be beneficial to patients with thalassemia and osteoporosis; other trials are investigating whether increasing ...

  2. Osteoporosis: Peak Bone Mass in Women

    Science.gov (United States)

    ... not supported by your browser. Home Osteoporosis Women Osteoporosis: Peak Bone Mass in Women Publication available in: ... drug products. NIH Pub. No. 15-7891 NIH Osteoporosis and Related Bone Diseases ~ National Resource Center 2 ...

  3. Scintigraphy of lower extremity cadaveric bone allografts in osteosarcoma patients.

    Science.gov (United States)

    Bar-Sever, Z; Connolly, L P; Gebhardt, M C; Treves, S T

    1997-08-01

    To describe scintigraphic characteristics of bone allografts used in limb salvage reconstruction after resection of lower extremity osteosarcoma. The authors reviewed 85 skeletal scintigrams of 20 pediatric patients followed up for 0.5-5.7 years after resection of lower extremity osteosarcoma and allograft reconstruction. Uptake in the allograft and adjacent host tissues was assessed visually. Lack of tracer uptake in the allografts was seen in 99% of the studies and a faint rim of tracer localization outlining the allograft's periphery was seen in 95% of the studies. Increased uptake was noted at the allograft-host bone junction in 78% of the studies. Uptake was increased in the joint surfaces of native bones articulating with allografts (97% of studies), including the patella (93% of studies) when the knee was involved. These findings were stabilized as time passed. Cadaveric bone allografts have a characteristic scintigraphic appearance in this selected patient group that reflects the physiology of their incorporation process.

  4. Bone mass and turnover in fibromyalgia

    DEFF Research Database (Denmark)

    Jacobsen, Søren; Gam, A; Egsmose, C

    1993-01-01

    Physical inactivity accelerates bone loss. Since patients with fibromyalgia are relatively physically inactive, bone mass and markers of bone metabolism were determined in 12 premenopausal women with fibromyalgia and in healthy age matched female control subjects. No differences were found...... in lumbar bone mineral density, femoral neck bone mineral density, serum levels of alkaline phosphatase, osteocalcin, ionized calcium and phosphate. The urinary excretion of both hydroxyproline and calcium relative to urinary creatinine excretion was significantly higher in patients with fibromyalgia, p = 0.......01. This was linked to lower urinary creatinine excretion (p = 0.02) probably reflecting lower physical activity in the patients with fibromyalgia. We conclude that bone mass and turnover are generally not affected in premenopausal women with fibromyalgia....

  5. Astrophysics of extreme mass ratio inspiral sources

    CERN Document Server

    Hopman, C

    2007-01-01

    Compact remnants on orbits with peri-apses close to the Schwarzschild radius of a massive black hole (MBH) lose orbital energy by emitting gravitational waves (GWs) and spiral in. Scattering with other stars allows successful inspiral of such extreme mass ratio inspiral sources (EMRIs) only within small distances, a < few \\times 0.01 pc from the MBH. The event rate of EMRIs is therefore dominated by the stellar dynamics and content in the inner few \\times 0.01 pc. I discuss the relevant dynamical aspects and resulting estimated event rates of EMRIs. Subjects considered include the loss-cone treatment of inspiral sources; mass segregation; resonant relaxation; and alternative routes to EMRI formation such as tidal binary disruptions, stellar formation in disks and tidal capture of massive main sequence stars. The EMRI event rate is estimated to be of order few \\times 10^2/Gyr per MBH, giving excellent prospects for observation by LISA.

  6. Association between Bone Mass and Dental Hypomineralization.

    Science.gov (United States)

    van der Tas, J T; Elfrink, M E C; Vucic, S; Heppe, D H M; Veerkamp, J S J; Jaddoe, V W V; Rivadeneira, F; Hofman, A; Moll, H A; Wolvius, E B

    2016-04-01

    The aim of this study was to examine the association between the bone mass (bone mineral content [BMC]) and hypomineralized second primary molars (HSPMs)/molar incisor hypomineralization (MIH) in 6-y-old children. This cross-sectional study was embedded in the Generation R Study, a population-based prospective cohort study, starting from fetal life until adulthood in Rotterdam, Netherlands. The European Academy of Pediatric Dentistry criteria were used to score the intraoral photographs on the presence or absence of HSPMs and MIH. Bone mass was measured with a dual-energy x-ray absorptiometry (DXA) scan. Intraoral photographs and DXA scans were available in 6,510 6-y-old children. Binary logistic regression models were used to study the association between the bone mass and HSPMs/MIH. In total, 5,586 children had their second primary molars assessed and a DXA scan made; 507 children were diagnosed with HSPM. Of 2,370 children with data on their permanent first molars, 203 were diagnosed with MIH. In the fully adjusted model, children with lower BMC (corrected for bone area) were more likely to have HSPMs (odds ratio, 1.13; 95% confidence interval, 1.02 to 1.26 per 1-standard deviation decrease). A lower BMC (corrected for bone area) was not associated with MIH (odds ratio, 1.02; 95% confidence interval, 0.87 to 1.20 per 1-standard deviation decrease). We observed a negative association between BMC (corrected for bone area) and HSPMs. No association was found between BMC (corrected for bone area) and MIH. Future research should focus on investigating the mechanism underlying the negative association between the bone mass and HSPMs. Our study, in a large population of 6-y-old children, adds the finding that BMC (corrected for bone size) is associated with HSPMs but not with MIH in childhood.

  7. Clinical assessment of bone mass in children

    Directory of Open Access Journals (Sweden)

    L A Sheplyagina

    2005-01-01

    Full Text Available Objective. To give clinical assessment of bone mass main indices in healthy children living in Moscow and Moscow region. Material and methods. 357 healthy children aged 5-16 years (194 male, 163 female were included. Physical development, bone mineral density (BMD by 2-power radiological absorptiometry, bone mineral content (BMC were evaluated. Results. Significant variability of height in children age groups was revealed. 40,2% had disharmonious physical development. BMC and BMD were closely associated with height (r=0,8, p=0,0001 and body mass (r=0,7, p=0,0001. Bone mass indices were proved to be significantly less in children with height and body mass less then 10% percentile. BMD growth rate was less than mineral accumulation rate. Method of body mass clinical assessment in children was elaborated. Conclusion. Application of elaborated tables of conjugated values of anthropometric and densitometric indices allows to decrease of osteopenia overdiagnosis in children and determine causes of insufficient bone mineral content.

  8. [Regulation of bone mass by osteocyte network].

    Science.gov (United States)

    Moriishi, Takeshi; Komori, Toshihisa

    2012-05-01

    Immobilization osteoporosis is a big issue in modern societies with aging population. Mechanical stress is essential for maintaining bone mass ; however, the mechanism of the regulation of bone mass by the osteocyte network, which comprises a communication system through processes and canaliculi throughout bone, still remains to be clarified. Therefore, it is urgent to reveal the mechanism of bone mass regulation at loaded and unloaded conditions and the physiological functions of the osteocyte network on osteoblasts and osteoclasts using appropriate mouse models such as a mouse line with the disrupted osteocyte function. We identified a novel mechanical stress-responsible molecule, pyruvate dehydrogenase kinase 4 (Pdk4) , whose expression was upregulated in osteoblasts at the unloaded condition, using a mouse model with the disrupted osteocyte function. We found that Pdk4 regulates Rankl expression in osteoblasts through the signal from the osteocyte network and induces osteoclastogenesis and bone resorption at the unloaded condition. The analyses using appropriate mouse models are gradually revealing the physiological roles of the osteocyte network, which were difficult to examine for a long time because of the anatomic sites of osteocytes that are embedded in bone matrix.

  9. Low bone mass in microscopic colitis

    Directory of Open Access Journals (Sweden)

    Lakatos Péter

    2011-05-01

    Full Text Available Abstract Background Microscopic colitis presents with similar symptoms to classic inflammatory bowel diseases. Osteoporosis is a common complication of Crohn's disease but there are no data concerning bone metabolism in microscopic colitis. Aims The aim of the present study was to evaluate bone density and metabolism in patients with microscopic colitis. Methods Fourteen patients microscopic colitis were included in the study, and 28 healthy persons and 28 age and gender matched Crohn's disease patients were enrolled as controls. Bone mineral density was measured using dual x-ray absorptiometry at the lumbar spine, femoral neck and the radius. Serum bone formation and bone resorption markers (osteocalcin and beta-crosslaps, respectively were measured using immunoassays. Results Low bone mass was measured in 57.14% patients with microscopic colitis. Bone mineral density at the femoral neck in patients suffering from microscopic colitis and Crohn's disease was lower than in healthy controls (0.852 ± 0.165 and 0.807 ± 0.136 vs. 1.056 ± 0.126 g/cm2; p 2; p 2. Mean beta-crosslaps concentration was higher in microscopic colitis and Crohn's disease patients than controls (417.714 ± 250.37 and 466.071 ± 249.96 vs. 264.75 ± 138.65 pg/ml; p Conclusions Low bone mass is frequent in microscopic colitis, and alterations to bone metabolism are similar to those present in Crohn's disease. Therefore, microscopic colitis-associated osteopenia could be a significant problem in such patients.

  10. Bone mass and bone metabolic indices in male master rowers.

    Science.gov (United States)

    Śliwicka, Ewa; Nowak, Alicja; Zep, Wojciech; Leszczyński, Piotr; Pilaczyńska-Szcześniak, Łucja

    2015-09-01

    The purpose of this study was to assess bone mass and bone metabolic indices in master athletes who regularly perform rowing exercises. The study was performed in 29 men: 14 master rowers and 15 non-athletic, body mass index-matched controls. Dual-energy X-ray absorptiometry measurements of the areal bone mineral density (aBMD) were performed for the total body, regional areas (arms, total forearms, trunk, thoracic spine, pelvis, and legs), lumbar spine (L1-L4), left hip (total hip and femoral neck), and forearm (33 % radius of the dominant and nondominant forearm). Serum concentrations of osteocalcin, collagen type I cross-linked C-telopeptide, visfatin, resistin, insulin, and glucose were determined. Comparative analyses showed significantly lower levels of body fat and higher lean body mass values in the rowers compared to the control group. The rowers also had significantly higher values of total and regional (left arm, trunk, thoracic spine, pelvis, and leg) BMD, as well as higher BMD values for the lumbar spine and the left hip. There were significant differences between the groups with respect to insulin, glucose, and the index of homeostasis model assessment insulin resistance. In conclusion, the systematic training of master rowers has beneficial effects on total and regional BMD and may be recommended for preventing osteoporosis.

  11. The myokine irisin increases cortical bone mass

    Science.gov (United States)

    Colaianni, Graziana; Cuscito, Concetta; Mongelli, Teresa; Pignataro, Paolo; Buccoliero, Cinzia; Liu, Peng; Lu, Ping; Sartini, Loris; Di Comite, Mariasevera; Mori, Giorgio; Di Benedetto, Adriana; Brunetti, Giacomina; Yuen, Tony; Sun, Li; Reseland, Janne E.; Colucci, Silvia; New, Maria I.; Zaidi, Mone; Cinti, Saverio; Grano, Maria

    2015-01-01

    It is unclear how physical activity stimulates new bone synthesis. We explored whether irisin, a newly discovered myokine released upon physical activity, displays anabolic actions on the skeleton. Young male mice were injected with vehicle or recombinant irisin (r-irisin) at a low cumulative weekly dose of 100 µg kg−1. We observed significant increases in cortical bone mass and strength, notably in cortical tissue mineral density, periosteal circumference, polar moment of inertia, and bending strength. This anabolic action was mediated primarily through the stimulation of bone formation, but with parallel notable reductions in osteoclast numbers. The trabecular compartment of the same bones was spared, as were vertebrae from the same mice. Higher irisin doses (3,500 µg kg−1 per week) cause browning of adipose tissue; this was not seen with low-dose r-irisin. Expectedly, low-dose r-irisin modulated the skeletal genes, Opn and Sost, but not Ucp1 or Pparγ expression in white adipose tissue. In bone marrow stromal cell cultures, r-irisin rapidly phosphorylated Erk, and up-regulated Atf4, Runx2, Osx, Lrp5, β-catenin, Alp, and Col1a1; this is consistent with a direct receptor-mediated action to stimulate osteogenesis. We also noted that, although the irisin precursor Fndc5 was expressed abundantly in skeletal muscle, other sites, such as bone and brain, also expressed Fndc5, albeit at low levels. Furthermore, muscle fibers from r-irisin–injected mice displayed enhanced Fndc5 positivity, and irisin induced Fdnc5 mRNA expression in cultured myoblasts. Our data therefore highlight a previously unknown action of the myokine irisin, which may be the molecular entity responsible for muscle–bone connectivity. PMID:26374841

  12. Determinants of bone mass and bone geometry in adolescent and young adult women

    NARCIS (Netherlands)

    Kardinaal, A.F.M.; Hoorneman, G.; Väänänen, K.; Charles, P.; Ando, S.; Maggiolini, M.; Charzewska, J.; Rotily, M.; Deloraine, A.; Heikkinen, J.; Juvin, R.; Schaafsma, G.

    2000-01-01

    Bone mass and bone geometry are considered to have independent effects on bone strength. The purpose of this study was to obtain data on bone mass and geometry in young female populations and how they are influenced by body size and lifestyle factors. In a cross-sectional, observational study in six

  13. Bone characteristics of late-term embryonic and hatchling broilers: bone development under extreme growth rate.

    Science.gov (United States)

    Yair, R; Uni, Z; Shahar, R

    2012-10-01

    The development of broilers is an extreme example of rapid growth, increasing in weight from 40 g at hatch to 2,000 g 5 to 6 wk later. Such rapid growth requires a correspondingly fast development of the skeleton. Bone development is a genetically programmed process that is modified by epigenetic factors, mainly muscle-induced stresses and strains. In this study, we describe the temporal changes in bone morphology and material properties during the prehatch period [embryonic day (E) 14, E17, E19, E21] and posthatch d 3 and 7. The bones were examined for their weight, length, ash content, mechanical properties, and cortical structure. We show that the cross-sectional shape of the tibia and femur changes during the examination period from circular to elliptical. Additionally, the changes in bone properties are time-dependent and nonuniform: from E14 to E17 and from d 3 to 7, fast bone growth was noted, with major increases in both mechanical properties (stiffness, ultimate load, and energy to fracture) and geometric properties (cross-sectional area and thickness, medullary area, and moment of inertia). On the other hand, during the last days of incubation, most mechanical and geometric properties remain unchanged or even decrease. The reasons for this finding may relate to the hatching process but also to mineral shortage during the last days of incubation. This study leads to better understanding of bone development in ovo and posthatch in fast-growing broilers.

  14. Common endocrine control of body weight, reproduction, and bone mass

    Science.gov (United States)

    Takeda, Shu; Elefteriou, Florent; Karsenty, Gerard

    2003-01-01

    Bone mass is maintained constant between puberty and menopause by the balance between osteoblast and osteoclast activity. The existence of a hormonal control of osteoblast activity has been speculated for years by analogy to osteoclast biology. Through the search for such humoral signal(s) regulating bone formation, leptin has been identified as a strong inhibitor of bone formation. Furthermore, intracerebroventricular infusion of leptin has shown that the effect of this adipocyte-derived hormone on bone is mediated via a brain relay. Subsequent studies have led to the identification of hypothalamic groups of neurons involved in leptin's antiosteogenic function. In addition, those neurons or neuronal pathways are distinct from neurons responsible for the regulation of energy metabolism. Finally, the peripheral mediator of leptin's antiosteogenic function has been identified as the sympathetic nervous system. Sympathomimetics administered to mice decreased bone formation and bone mass. Conversely, beta-blockers increased bone formation and bone mass and blunted the bone loss induced by ovariectomy.

  15. Lower Bone Mass and Higher Bone Resorption in Pheochromocytoma: Importance of Sympathetic Activity on Human Bone.

    Science.gov (United States)

    Kim, Beom-Jun; Kwak, Mi Kyung; Ahn, Seong Hee; Kim, Hyeonmok; Lee, Seung Hun; Song, Kee-Ho; Suh, Sunghwan; Kim, Jae Hyeon; Koh, Jung-Min

    2017-08-01

    Despite the apparent biological importance of sympathetic activity on bone metabolism in rodents, its role in humans remains questionable. To clarify the link between the sympathetic nervous system and the skeleton in humans. Among 620 consecutive subjects with newly diagnosed adrenal incidentaloma, 31 patients with histologically confirmed pheochromocytoma (a catecholamine-secreting neuroendocrine tumor) and 280 patients with nonfunctional adrenal incidentaloma were defined as cases and controls, respectively. After adjustment for confounders, subjects with pheochromocytoma had 7.2% lower bone mass at the lumbar spine and 33.5% higher serum C-terminal telopeptide of type 1 collagen (CTX) than those without pheochromocytoma (P = 0.016 and 0.001, respectively), whereas there were no statistical differences between groups in bone mineral density (BMD) at the femur neck and total hip and in serum bone-specific alkaline phosphatase (BSALP) level. The odds ratio (OR) for lower BMD at the lumbar spine in the presence of pheochromocytoma was 3.31 (95% confidence interval, 1.23 to 8.56). However, the ORs for lower BMD at the femur neck and total hip did not differ according to the presence of pheochromocytoma. Serum CTX level decreased by 35.2% after adrenalectomy in patients with pheochromocytoma, whereas serum BSALP level did not change significantly. This study provides clinical evidence showing that sympathetic overstimulation in pheochromocytoma can contribute to adverse effects on human bone through the increase of bone loss (especially in trabecular bone), as well as bone resorption.

  16. Follicle-stimulating hormone increases bone mass in female mice.

    Science.gov (United States)

    Allan, Charles M; Kalak, Robert; Dunstan, Colin R; McTavish, Kirsten J; Zhou, Hong; Handelsman, David J; Seibel, Markus J

    2010-12-28

    Elevated follicle-stimulating hormone (FSH) activity is proposed to directly cause bone loss independent of estradiol deficiency in aging women. Using transgenic female mice expressing human FSH (TgFSH), we now reveal that TgFSH dose-dependently increased bone mass, markedly elevating tibial and vertebral trabecular bone volume. Furthermore, TgFSH stimulated a striking accrual of bone mass in hypogonadal mice lacking endogenous FSH and luteinizing hormone (LH) function, showing that FSH-induced bone mass occurred independently of background LH or estradiol levels. Higher TgFSH levels increased osteoblast surfaces in trabecular bone and stimulated de novo bone formation, filling marrow spaces with woven rather than lamellar bone, reflective of a strong anabolic stimulus. Trabecular bone volume correlated positively with ovarian-derived serum inhibin A or testosterone levels in TgFSH mice, and ovariectomy abolished TgFSH-induced bone formation, proving that FSH effects on bone require an ovary-dependent pathway. No detectable FSH receptor mRNA in mouse bone or cultured osteoblasts or osteoclasts indicated that FSH did not directly stimulate bone. Therefore, contrary to proposed FSH-induced bone loss, our findings demonstrate that FSH has dose-dependent anabolic effects on bone via an ovary-dependent mechanism, which is independent of LH activity, and does not involve direct FSH actions on bone cells.

  17. Fatigue, bone pain, lower extremity weakness and bone mineral density%乏力、骨痛、双下肢酸软与骨密度

    Institute of Scientific and Technical Information of China (English)

    徐秀兰; 陈莉; 张童茜; 施宝颖

    2011-01-01

    Objective To explore the relationship among fatigue, bone pain, weakness in both lower extremities, and bone mineral density. Methods The bone mineral density of the lumbar vertebra 1-4 ( LI -4) and the femoral neck was measured in 2069 clinical patients with fatigue, bone pain, and weakness in both lower extremities. Results Most patients with above symptoms were women, especially those who were over SO years of age. Most patients existed abnormal bone mass. The lower the bone mass wag, the more severe the pain was. The incidence of osteoporosis increased with age growing.%目的 探讨乏力、骨痛、双下肢酸软等症状与骨密度的关系.方法 对2069名以乏力、骨痛及双下肢酸软临床症状就诊者进行了腰椎( L1-4)及股骨颈骨密度测定.结果 以此症状就诊者女性居多,且以50岁为甚,就诊者中大多存在着骨量异常,骨量越低,疼痛程度越重,随着年龄增大,骨质疏松发病率也随之增高.结论 疼痛程度与骨量下降、年龄增长成正比.

  18. Design and Manufacturing of Extremely Low Mass Flight Systems

    Science.gov (United States)

    Johnson, Michael R.

    2002-01-01

    Extremely small flight systems pose some unusual design and manufacturing challenges. The small size of the components that make up the system generally must be built with extremely tight tolerances to maintain the functionality of the assembled item. Additionally, the total mass of the system is extremely sensitive to what would be considered small perturbations in a larger flight system. The MUSES C mission, designed, built, and operated by Japan, has a small rover provided by NASA that falls into this small flight system category. This NASA-provided rover is used as a case study of an extremely small flight system design. The issues that were encountered with the rover portion of the MUSES C program are discussed and conclusions about the recommended mass margins at different stages of a small flight system project are presented.

  19. Lumbar bone mass predicts low back pain in males

    NARCIS (Netherlands)

    Hoozemans, M.J.M.; Koppes, L.L.J.; Twisk, J.W.R.; Dieën, J.H. van

    2012-01-01

    STUDY DESIGN.: Longitudinal study of lumbar bone mass as predictor of low back pain (LBP). OBJECTIVE.: To investigate whether low bone mineral content (BMC) and bone mineral density (BMD) values at the age of 36 years are associated with the prevalence of LBP at the age of 42 years among the study p

  20. Androgen and bone mass in men

    Institute of Scientific and Technical Information of China (English)

    AnnieW.C.Kung

    2003-01-01

    Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function,activity and lifespan through complex mechanisms. Also androgens increase periosteal bone apposition, resulting in larger bone size and thicker cortical bone in men. There is convincing evidence to show that aromatization to estrogens was an important pathway for mediating the action of testosterone on bone physiology. Estrogen is probably the dominant sex steroid regulating bone resorption in men, but both testosterone and estrogen are important in maintaining bone formation. ( Asian J Androl 2003 Jun; 5: 148-154)

  1. Tooth-marked small theropod bone: an extremely rare trace

    DEFF Research Database (Denmark)

    Jacobsen, Aase Roland

    2001-01-01

    Tooth-marked dinosaur bones provide insight into feeding behaviours and biting strategies of theropod dinosaurs. The majority of theropod tooth marks reported to date have been found on herbivorous dinosaur bones, although some tyrannosaurid bones with tooth marks have also been reported. In 1988...

  2. 3,3′-Diindolylmethane increases bone mass by suppressing osteoclastic bone resorption in mice

    Directory of Open Access Journals (Sweden)

    Tai-yong Yu

    2015-01-01

    Full Text Available 3,3′-Diindolylmethane (DIM, a major acid-condensation product or metabolite of indole-3-carbinol which is found in cruciferous vegetables, has been shown to have anticancer, anti-inflammatory, and multiple immune stimulating effects. However, its function in bone metabolism is poorly understood. This study evaluated the effect of DIM on bone mass in mice under physiological and pathological conditions. Eight-week-old female mice received injections of a vehicle or 0.1 mg/g of DIM, twice a week for four weeks. We found that DIM treatment significantly increased bone mass as assessed by dual-energy X-ray absorptiometry (DEXA and micro-computed tomography (μCT. Further, Bone histomorphometric analyses showed that this treatment significantly reduced bone resorption parameters, but did not increase bone formation parameters. Furthermore, we use ovariectomized (OVX-induced osteoporotic mouse model, and explore function of DIM in skeletal pathological processes. Bone phenotype analyses revealed that the administration of DIM in this study effectively prevented OVX-induced bone loss resulting from increased bone resorption. Our results demonstrated that DIM increased bone mass by suppressing osteoclastic bone resorption in bone metabolism under both physiological and pathological conditions. Accordingly, DIM may be of value in the treatment and the possible prevention of bone diseases characterized by bone loss, such as postmenopausal osteoporosis.

  3. Research Update on Extreme-Mass-Ratio Inspirals

    Science.gov (United States)

    Amaro-Seoane, Pau; Gair, Jonathan R.; Pound, Adam; Hughes, Scott A.; Sopuerta, Carlos F.

    2015-05-01

    The inspirals of stellar-mass mass compact objects into massive black holes in the centres of galaxies are one of the most important sources of gravitational radiation for space- based detectors like LISA or eLISA. These extreme-mass-ratio inspirals (EMRIs) will enable an ambitious research program with implications for astrophysics, cosmology, and fundamental physics. This article is a summary of the talks delivered at the plenary session on EMRIs at the 10th International LISA Symposium. It contains research updates on the following topics: astrophysics of EMRIs; EMRI science potential; and EMRI modeling.

  4. Diet-induced Obesity Alters Bone Remodeling Leading to Decreased Femoral Trabecular Bone Mass in Mice

    Science.gov (United States)

    Body mass derived from an obesity condition may be detrimental to bone health but the mechanism is unknown. This study was to examine changes in bone structure and serum cytokines related to bone metabolism in obese mice induced by a high-fat diet(HFD). Mice fed the HFD were obese and had higher ser...

  5. DXA measurements in rett syndrome reveal small bones with low bone mass

    DEFF Research Database (Denmark)

    Roende, Gitte; Ravn, Kirstine; Fuglsang, Kathrine

    2011-01-01

    Low bone mass is reported in growth-retarded patients harboring mutations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene causing Rett syndrome (RTT). We present the first study addressing both bone mineral density (BMD) and bone size in RTT. Our object was to determine whether patients...

  6. The Effect of Estrogen on the Restoration of Bone Mass and Bone Quality in Ovariectomized Rats

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To evaluate the effect of estrogen on its ability to restore the bone mass and bone quality in ovariectomized rats by examining the changes of bone morphology and histomorphometry, 3month-old rats were divided randomly into 4 groups: normal control, ovariectomized (OVX), shamoperated (Sham-O) and OVX plus estrogen (OVX+E2). Treatment initiated from the day 8 weeks after operation and continued for 12 weeks. Bone morphology and histomorphometry were examined afterwards. Results showed that comparing to control group, the trabecular bone in OVX appeared thinner and reduced in the amount. The connectivity between trabecula was decreased and the structure disordered. The free-end of trabecula was increased. The cavity of bone marrow enlarged. After treatment with estrogen, above changes improved remarkably by different degree, although did not reach the normal face. The bone histomorphometry results damonstrated that estrogen treatment increased bone mass and the amount of trabecula by 129% and 132% respectively (P<0. 05). The activity of bone resorption decreased significantly and the rate of bone formation increased to 203 %. These results suggest that treatment of ovariectomized rats with estrogen can not only increase bone mass, also improve the bone structure and enhance the property of bone mechanics.

  7. [Effects of SERMs on bone health. Mechanisms of bone mass control by selective estrogen receptor modulator].

    Science.gov (United States)

    Imai, Yuuki; Kato, Shigeaki

    2010-03-01

    The bone mass, which is controlled by the balances between bone formation and bone resorption can be reduced by estrogen deficiency in post-menopausal osteoporosis. Reduced bone mass can be recovered by hormone replacement therapy (HRT) , however, HRT has various side effects. Although SERMs can rescue the bone mass with less side effect compared to HRT, the precise mechanisms of this effect is still elusive. From the results of the analyses for osteoclast specific estrogen receptor (ER) alphaknockout mice and the genome wide approach of ERalphabinding site, estrogen and SERMs can, at least in part, protect the bone mass by inducing the expression of Fas ligand and controling the life span of osteoclasts. More precise molecular mechanisms of the effect of SERM, especially in tissue/cell type specificity, may help to investigate new SERM, which is more specific and effective to treat post-menopausal osteoporosis.

  8. High bone turnover is associated with low bone mass in both pre- and postmenopausal women

    DEFF Research Database (Denmark)

    Ravn, Pernille; Fledelius, C; Rosenquist, C

    1996-01-01

    In 979 healthy women, aged 30-75 years, bone mass was measured by DXA in the lumbar spine and proximal femur, and by SXA in the distal forearm. Bone turnover was assessed by urinary CrossLaps (CrossLaps ELISA), a new assay which measures type I collagen degradation products in urine and by osteoc......In 979 healthy women, aged 30-75 years, bone mass was measured by DXA in the lumbar spine and proximal femur, and by SXA in the distal forearm. Bone turnover was assessed by urinary CrossLaps (CrossLaps ELISA), a new assay which measures type I collagen degradation products in urine...... of CrossLaps and OCN-Mid corrected for height and weight, had 6%-11% lower bone mass in all regions (p height and weight correlated with bone mass in the spine and proximal femur, r = -0.13 to r = -0.28, p

  9. Trephination and subatmospheric pressure therapy in the management of extremity exposed bone.

    Science.gov (United States)

    Chen, Wei F; Poulakidas, Stathis J; Kowal-Vern, Areta; Villare, Robert C

    2010-12-01

    Distal lower and upper extremity wounds with bone and tendon exposure present unique challenges to reconstructive surgeons. The limitations of the local anatomy usually make simpler reconstructive modalities such as primary closure and skin grafting difficult. As a result, wounds in this area, especially ones with bone or tendon exposures, are classically treated with free tissue transfer. Limb preservation using the combination of bone trephination and subatmospheric pressure therapy is described. Six cases with preserved extremities are presented. Three cases illustrate extremity wound with bone and tendon exposure healing through pregrafting wound optimization (bone trephination) with the use of subatmospheric pressure therapy. This treatment may offer an alternative method of limb salvage, in cases where flaps or free tissue transfer are not possible or optimal.

  10. The relationship between the bone mineral content and lean mass in the hemiplegic extremity in patients after stroke%脑卒中患者偏瘫肢体骨量丢失与肌肉萎缩程度的关系

    Institute of Scientific and Technical Information of China (English)

    吴畏; 冯波; 黄东雅; 徐晓云

    2011-01-01

    目的 观察脑卒中后偏瘫患者健患侧肢体骨量、瘦组织和脂肪组织含量的变化,探讨骨量丢失与肌肉萎缩程度的关系。方法 选择脑卒中后偏瘫患者61例,采用双能X线骨密度仪(DEXA)测定其健患侧肢体骨矿含量及体质成分。结果 与健侧肢体相比,患侧肢体脂肪含量、肌肉含量及BMC明显下降(P<0.01),BMC下降程度与肌肉含量减少呈明显正相关,而与脂肪含量变化无明显关系。与女性患者相比,男性患者肌肉含量、BMC含量显著增高,而脂肪含量显著降低。结论 脑卒中偏瘫病人患侧肢体骨量、肌肉和脂肪含量均明显降低,肌肉含量变化在维持骨量方面起重要作用。%Objective To observe the alteration of bone mineral content (BMC) , lean mass (LM), and fat mass ( FM ) in both diseased and non-diseased extremities of hemiplegic patients after stoke, and to investigate the relationship between loss of BMC and extend of muscle atrophy. Methods BMC and body elements of both diseased and non-diseased extremities were measured using a dual-energy X-ray absorptiometry (DXA) in 61 hemiplegic patients after stroke. Results There was significant decrease in FM, LM, and BMC in the paretic extremity, compared to the non-paretic extremity (P < 0.01). The decrease of BMC correlated significantly with the decrease of LM, but did not correlated with the alteration of FM. Compared to those in female patients, LM and BMC increased, but FM decreased significantly in male patients. Conclusion There was significant loss in BMC, LM, and FM in the hemiplegic extremity in patients after stroke. The alteration of LM played an important role in maintaining BMC.

  11. Solid variant of aneurysmal bone cist on the distal extremity of the radius in a child.

    Science.gov (United States)

    Ferreira, Adriano Jander; de Almeida Leitão, Sebastião; Rocha, Murilo Antônio; Nascimento, Valdênia das Graças; Lima, Giovanni Bessa Pereira; de Meneses, Antonio Carlos Oliveira

    2016-01-01

    The solid variant of aneurismal bone cysts (ABC) is considered rare. It occurs with greater frequency in pediatric patients and in the tibia, femur, pelvis and humerus. We present a case of a metaphyseal lytic lesion on the distal extremity of the radius in a child whose radiograph was requested after low-energy trauma. The hypothesis of a pathological bone fracture secondary to an aneurysmal bone cyst was suggested. After biopsy, the child underwent intralesional excision without bone grafting and the histopathological findings were compatible with the solid variant of aneurysmal bone cyst.

  12. High-density lipoprotein (HDL) metabolism and bone mass.

    Science.gov (United States)

    Papachristou, Nicholaos I; Blair, Harry C; Kypreos, Kyriakos E; Papachristou, Dionysios J

    2017-05-01

    It is well appreciated that high-density lipoprotein (HDL) and bone physiology and pathology are tightly linked. Studies, primarily in mouse models, have shown that dysfunctional and/or disturbed HDL can affect bone mass through many different ways. Specifically, reduced HDL levels have been associated with the development of an inflammatory microenvironment that affects the differentiation and function of osteoblasts. In addition, perturbation in metabolic pathways of HDL favors adipoblastic differentiation and restrains osteoblastic differentiation through, among others, the modification of specific bone-related chemokines and signaling cascades. Increased bone marrow adiposity also deteriorates bone osteoblastic function and thus bone synthesis, leading to reduced bone mass. In this review, we present the current knowledge and the future directions with regard to the HDL-bone mass connection. Unraveling the molecular phenomena that underline this connection will promote the deeper understanding of the pathophysiology of bone-related pathologies, such as osteoporosis or bone metastasis, and pave the way toward the development of novel and more effective therapies against these conditions. © 2017 Society for Endocrinology.

  13. Bone Mass Measurement: What the Numbers Mean

    Science.gov (United States)

    ... young adult mean (−1 to −2.5 SD). Osteoporosis Bone density is 2.5 SD or more below the young adult mean (−2.5 SD or lower). Severe (established) osteoporosis Bone density is more than 2.5 SD below the young adult mean, and there have been one or more ...

  14. Relationship between body fat mass and bone metabolism.

    Science.gov (United States)

    Holecki, Michał; Wiecek, Andrzej

    2010-09-01

    The protective effect of obesity on bone tissue has not been unequivocally demonstrated. On one hand, it is known that obese people have a lower risk of osteoporotic fractures compared with normal-weight individuals. On the other hand, obese patients are characterized by disorders of calcium-phosphate homeostasis and bone metabolism. Moreover, it is not known whether it is fat or lean body mass that determines the development of bone mass. It can be assumed that adipose tissue exerts independent effects on bone remodeling by releasing a number of biologically active substances. Moreover, it seems that the main mechanism of action of these substances is closely related to the type and location of adipose tissue in the body. The present article describes the relationship between fat and bones, including the effect of body weight on bone tissue, the local mechanisms of osteoblast and adipocyte differentiation, and the hormonal activity of adipose tissue.

  15. Functions of vasopressin and oxytocin in bone mass regulation

    Science.gov (United States)

    Sun, Li; Tamma, Roberto; Yuen, Tony; Colaianni, Graziana; Ji, Yaoting; Cuscito, Concetta; Bailey, Jack; Dhawan, Samarth; Lu, Ping; Calvano, Cosima D.; Zhu, Ling-Ling; Zambonin, Carlo G.; Di Benedetto, Adriana; Stachnik, Agnes; Liu, Peng; Grano, Maria; Colucci, Silvia; Davies, Terry F.; New, Maria I.; Zallone, Alberta; Zaidi, Mone

    2016-01-01

    Prior studies show that oxytocin (Oxt) and vasopressin (Avp) have opposing actions on the skeleton exerted through high-affinity G protein-coupled receptors. We explored whether Avp and Oxtr can share their receptors in the regulation of bone formation by osteoblasts. We show that the Avp receptor 1α (Avpr1α) and the Oxt receptor (Oxtr) have opposing effects on bone mass: Oxtr−/− mice have osteopenia, and Avpr1α−/− mice display a high bone mass phenotype. More notably, this high bone mass phenotype is reversed by the deletion of Oxtr in Oxtr−/−:Avpr1α−/− double-mutant mice. However, although Oxtr is not indispensable for Avp action in inhibiting osteoblastogenesis and gene expression, Avp-stimulated gene expression is inhibited when the Oxtr is deleted in Avpr1α−/− cells. In contrast, Oxt does not interact with Avprs in vivo in a model of lactation-induced bone loss in which Oxt levels are high. Immunofluorescence microscopy of isolated nucleoplasts and Western blotting and MALDI-TOF of nuclear extracts show that Avp triggers Avpr1α localization to the nucleus. Finally, a specific Avpr2 inhibitor, tolvaptan, does not affect bone formation or bone mass, suggesting that Avpr2, which primarily functions in the kidney, does not have a significant role in bone remodeling. PMID:26699482

  16. A quantification strategy for missing bone mass in case of osteolytic bone lesions

    Energy Technology Data Exchange (ETDEWEB)

    Fränzle, Andrea, E-mail: a.fraenzle@dkfz.de; Giske, Kristina [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Bretschi, Maren; Bäuerle, Tobias [Department of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Hillengass, Jens [Department of Internal Medicine V, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Bendl, Rolf [Medical Informatics, Heilbronn University, Max-Planck-Strasse 39, 74081 Heilbronn, Germany and Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

    2013-12-15

    Purpose: Most of the patients who died of breast cancer have developed bone metastases. To understand the pathogenesis of bone metastases and to analyze treatment response of different bone remodeling therapies, preclinical animal models are examined. In breast cancer, bone metastases are often bone destructive. To assess treatment response of bone remodeling therapies, the volumes of these lesions have to be determined during the therapy process. The manual delineation of missing structures, especially if large parts are missing, is very time-consuming and not reproducible. Reproducibility is highly important to have comparable results during the therapy process. Therefore, a computerized approach is needed. Also for the preclinical research, a reproducible measurement of the lesions is essential. Here, the authors present an automated segmentation method for the measurement of missing bone mass in a preclinical rat model with bone metastases in the hind leg bones based on 3D CT scans. Methods: The affected bone structure is compared to a healthy model. Since in this preclinical rat trial the metastasis only occurs on the right hind legs, which is assured by using vessel clips, the authors use the left body side as a healthy model. The left femur is segmented with a statistical shape model which is initialised using the automatically segmented medullary cavity. The left tibia and fibula are segmented using volume growing starting at the tibia medullary cavity and stopping at the femur boundary. Masked images of both segmentations are mirrored along the median plane and transferred manually to the position of the affected bone by rigid registration. Affected bone and healthy model are compared based on their gray values. If the gray value of a voxel indicates bone mass in the healthy model and no bone in the affected bone, this voxel is considered to be osteolytic. Results: The lesion segmentations complete the missing bone structures in a reasonable way. The mean

  17. THE METHOD OF TREATMENT OF PATIENTS WITH NONUNIONS AND GUNSHOT PSEUDOARTHROSIS OF LONG BONE OF EXTREMITIES

    Directory of Open Access Journals (Sweden)

    B. A. Akhmedov

    2010-01-01

    Full Text Available Developed by the authors the method of treatment for nonunions and pseudoarthrosis of extremities long bones is described. It consist in mini-invasive preparation of interfragmentary space and bone grafting with cancellous graft from the wing of ilium. Successful use this method in 23 patients with gunshot wounds of humeral, forearm, femur and shin bones allows to recommend it for wide application. Suggested method of surgical treatment can be used not only after gunshot wounds, but after long bones fractures of another genesis.

  18. Effects of the gut microbiota on bone mass.

    Science.gov (United States)

    Ohlsson, Claes; Sjögren, Klara

    2015-02-01

    The gut microbiota (GM), the commensal bacteria living in our intestine, performs numerous useful functions, including modulating host metabolism and immune status. Recent studies demonstrate that the GM is also a regulator of bone mass and it is proposed that the effect of the GM on bone mass is mediated via effects on the immune system, which in turn regulates osteoclastogenesis. Under normal conditions, the skeleton is constantly remodeled by bone-forming osteoblasts (OBs) and bone-resorbing osteoclasts (OCLs), and imbalances in this process may lead to osteoporosis. Here we review current knowledge on the possible role for the GM in the regulation of bone metabolism and propose that the GM might be a novel therapeutic target for osteoporosis and fracture prevention. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Association between fat mass, lean mass, and bone loss: the Dubbo Osteoporosis Epidemiology Study.

    Science.gov (United States)

    Yang, S; Center, J R; Eisman, J A; Nguyen, T V

    2015-04-01

    Lower body fat mass is a risk factor for bone loss at lumbar spine in postmenopausal women, but not in men. Body lean mass and fat mass were not associated with femoral neck bone loss in either gender. Bone density and body mass are closely associated. Whole body lean mass (LM) and fat mass (FM) together account for approximately 95 % of body mass. Bone loss is associated with loss of body mass but which of the components of body mass (FM or LM) is related to bone loss is not well understood. Therefore, in this study, we sought to assess whether baseline FM or LM has predictive value for future relative rate of bone mineral density (BMD) changes (%/year). The present population-based cohort study was part of the ongoing Dubbo Osteoporosis Epidemiology Study (DOES). BMD, FM, and LM were measured with dual energy X-ray absorptiometry (GE-LUNAR Corp, Madison, WI). BMD measurements were taken in approximately every 2 years between 2000 and 2010. We only included the participants with at least two BMD measurements at the femoral neck and lumbar spine. In total, 717 individuals (204 men and 513 women) aged 50 years or older were studied. Rate of bone loss at femoral neck and lumbar spine was faster in women than in men (all P loss at lumbar spine. This magnitude of association remained virtually unchanged after adjusting for LM and/or other covariates (P = 0.03). After adjusting for covariates, variation of FM accounted for ∼1.5 % total variation in lumbar spine bone loss. However, there was no significant association between FM and change in femoral neck BMD in either men or women. Lower FM was an independent but modest risk factor for greater bone loss at the lumbar spine in women but not in men. If further studies confirm our findings, FM can help predict lumbar spine bone loss in women.

  20. DXA measurements in Rett syndrome reveal small bones with low bone mass.

    Science.gov (United States)

    Roende, Gitte; Ravn, Kirstine; Fuglsang, Kathrine; Andersen, Henrik; Nielsen, Jytte Bieber; Brøndum-Nielsen, Karen; Jensen, Jens-Erik Beck

    2011-09-01

    Low bone mass is reported in growth-retarded patients harboring mutations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene causing Rett syndrome (RTT). We present the first study addressing both bone mineral density (BMD) and bone size in RTT. Our object was to determine whether patients with RTT do have low BMD when correcting for smaller bones by examination with dual-energy X-ray absorptiometry (DXA). We compared areal BMD (aBMD(spine) and aBMD(total hip) ) and volumetric bone mineral apparent density (vBMAD(spine) and vBMAD(neck) ) in 61 patients and 122 matched healthy controls. Further, spine and hip aBMD and vBMAD of patients were associated with clinical risk factors of low BMD, low-energy fractures, MECP2 mutation groups, and X chromosome inactivation (XCI). Patients with RTT had reduced bone size on the order of 10% and showed lower values of spine and hip aBMD and vBMAD (p bone mass and small bones are evident in RTT, indicating an apparent low-bone-formation phenotype.

  1. Peripubertal female athletes in high-impact sports show improved bone mass acquisition and bone geometry.

    Science.gov (United States)

    Maïmoun, Laurent; Coste, Olivier; Philibert, Pascal; Briot, Karine; Mura, Thibault; Galtier, Florence; Mariano-Goulart, Denis; Paris, Françoise; Sultan, Charles

    2013-08-01

    Intensive physical training may have a sport-dependent effect on bone mass acquisition. This cross-sectional study evaluated bone mass acquisition in girls practicing sports that put different mechanical loads on bone. Eighty girls from 10.7 to 18.0 years old (mean 13.83 ± 1.97) were recruited: 20 artistic gymnasts (AG; high-impact activity), 20 rhythmic gymnasts (RG; medium-impact activity), 20 swimmers (SW, no-impact activity), and 20 age-matched controls (CON; leisure physical activity activity clearly had a favorable effect on aBMD and bone geometry during the growth period, although the bone health benefits seem to be more marked after menarche. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Professional sport activity and micronutrients: effects on bone mass.

    Science.gov (United States)

    Nuti, R; Martini, G; Merlotti, D; Valleggi, F; De Paola, V; Gennari, L

    2005-01-01

    Osteoporosis is the most prevalent metabolic bone disease among developed countries. Although bone mass and density are certainly determined by various concurrent factors such as genetics, hormones, life-style and the environment, and although the genetic program has a critical role in growth and in bone peak development, for their realization an adequate nutritional intake of nutrients and regular exercise are always necessary and may represent a way to prevent osteoporosis and fractures. Exercise and especially high-impact sport activity during growth and adolescence increases bone mineral density (BMD) in weight-loaded skeletal regions. Aerobics, weight bearing and resistance exercises may also be effective in increasing BMD in post-menopausal women. Even though most of the research on nutritional components has focused almost exclusively on calcium and vitamin D, there is now considerable interest in the effects of a variety of other nutrients on bone status.

  3. Wntless functions in mature osteoblasts to regulate bone mass.

    Science.gov (United States)

    Zhong, Zhendong; Zylstra-Diegel, Cassandra R; Schumacher, Cassie A; Baker, Jacob J; Carpenter, April C; Rao, Sujata; Yao, Wei; Guan, Min; Helms, Jill A; Lane, Nancy E; Lang, Richard A; Williams, Bart O

    2012-08-14

    Recent genome-wide association studies of individuals of Asian and European descent have found that SNPs located within the genomic region (1p31.3) encoding the Wntless (Wls)/Gpr177 protein are associated significantly with reduced bone mineral density. Wls/Gpr177 is a newly identified chaperone protein that specifically escorts Wnt ligands for secretion. Given the strong functional association between the Wnt signaling pathways and bone development and homeostasis, we generated osteoblast-specific Wls-deficient (Ocn-Cre;Wls-flox) mice. Homozygous conditional knockout animals were born at a normal Mendelian frequency. Whole-body dual-energy X-ray absorptiometry scanning revealed that bone-mass accrual was significantly inhibited in homozygotes as early as 20 d of age. These homozygotes had spontaneous fractures and a high frequency of premature lethality at around 2 mo of age. Microcomputed tomography analysis and histomorphometric data revealed a dramatic reduction of both trabecular and cortical bone mass in homozygous mutants. Bone formation in homozygotes was severely impaired, but no obvious phenotypic change was observed in mice heterozygous for the conditional deletion. In vitro studies showed that Wls-deficient osteoblasts had a defect in differentiation and mineralization, with significant reductions in the expression of key osteoblast differentiation regulators. In summary, these results reveal a surprising and crucial role of osteoblast-secreted Wnt ligands in bone-mass accrual.

  4. The Capra Research Program for Modelling Extreme Mass Ratio Inspirals

    CERN Document Server

    Thornburg, Jonathan

    2011-01-01

    Suppose a small compact object (black hole or neutron star) of mass $m$ orbits a large black hole of mass $M \\gg m$. This system emits gravitational waves (GWs) that have a radiation-reaction effect on the particle's motion. EMRIs (extreme--mass-ratio inspirals) of this type will be important GW sources for LISA; LISA's data analysis will require highly accurate EMRI GW templates. In this article I outline the "Capra" research program to try to model EMRIs and calculate their GWs \\textit{ab initio}, assuming only that $m \\ll M$ and that the Einstein equations hold. Here we treat the EMRI spacetime as a perturbation of the large black hole's "background" (Schwarzschild or Kerr) spacetime and use the methods of black-hole perturbation theory, expanding in the small parameter $m/M$. The small body's motion can be described either as the result of a radiation-reaction "self-force" acting in the background spacetime or as geodesic motion in a perturbed spacetime. Several different lines of reasoning lead to the (s...

  5. LISA extreme-mass-ratio inspiral events as probes of the black hole mass function

    CERN Document Server

    Gair, Jonathan R; Volonteri, Marta

    2010-01-01

    One of the sources of gravitational waves for the proposed space-based gravitational wave detector, the Laser Interferometer Space Antenna (LISA), are the inspirals of compact objects into supermassive black holes in the centres of galaxies - extreme-mass-ratio inspirals (EMRIs). Using LISA observations, we will be able to measure the parameters of each EMRI system detected to very high precision. However, the statistics of the set of EMRI events observed by LISA will be more important in constraining astrophysical models than extremely precise measurements for individual systems. The black holes to which LISA is most sensitive are in a mass range that is difficult to probe using other techniques, so LISA provides an almost unique window onto these objects. In this paper we explore, using Bayesian techniques, the constraints that LISA EMRI observations can place on the mass function of black holes at low redshift. We describe a general framework for approaching inference of this type --- using multiple observ...

  6. Effect of Probiotics Supplementation on Bone Mineral Content and Bone Mass Density

    Directory of Open Access Journals (Sweden)

    Kolsoom Parvaneh

    2014-01-01

    Full Text Available A few studies in animals and a study in humans showed a positive effect of probiotic on bone metabolism and bone mass density. Most of the investigated bacteria were Lactobacillus and Bifidobacterium . The positive results of the probiotics were supported by the high content of dietary calcium and the high amounts of supplemented probiotics. Some of the principal mechanisms include (1 increasing mineral solubility due to production of short chain fatty acids; (2 producing phytase enzyme by bacteria to overcome the effect of mineral depressed by phytate; (3 reducing intestinal inflammation followed by increasing bone mass density; (4 hydrolysing glycoside bond food in the intestines by Lactobacillus and Bifidobacteria. These mechanisms lead to increase bioavailability of the minerals. In conclusion, probiotics showed potential effects on bone metabolism through different mechanisms with outstanding results in the animal model. The results also showed that postmenopausal women who suffered from low bone mass density are potential targets to consume probiotics for increasing mineral bioavailability including calcium and consequently increasing bone mass density.

  7. Peak Bone Mass Measurement in Iranian Healthy Population

    Directory of Open Access Journals (Sweden)

    B Larijani

    2007-08-01

    Full Text Available Background: Osteoporosis is a disabling disease characterized by compromised bone strength, which predisposes a patient to increased risk of fracture. The aim of this study was evaluation the pattern of bone mass in Iranian healthy population. Methods: The study was performed between December 2000 and May 2001 on one thousand three healthy Iranian sub¬jects who currently live in Tehran. They were selected randomly by cluster random sampling among men and women of 10-76 yr from 50 clusters. The volunteer people were referred to the Bone Mineral Density BMD unit of EMRC. The partici¬pants were recalled for three times and the response rate was 83%. BMD was measured by DXA using Lunar DPX-MD device. Results: Females achieved maximum lumbar BMD up to 25-35. Femur BMD maximized in 30 to 35 and after 45 the inten¬sity of bone loss increased. Female peak bone mass in lumbar region was 1.19 ± 0.12 g/cm2and in femur was 1.02±0.12 g/cm2. Male peak bone mass in lumbar region occurred between ages 25-40 yr, Male's femur BMD maximized in 20-30. In male peak lumbar bone mass was 1.22±0.16 g/cm2 and femur was 1.08±0.15 g/cm2. Osteopenia was recog¬nized in 50% and 48.8% of women above 50 in spine and total femur, respectively, however these percentages were 37.1% and 34.8% among male subjects. Conclusion: Iranian BMD values sufficiently different from other countries to warrant a separate reference sample with which to compare individuals for the purpose of diagnosing osteoporosis and osteopenia according to the WHO criteria.

  8. Extreme mass ratio inspiral rates: dependence on the massive black hole mass

    CERN Document Server

    Hopman, Clovis

    2009-01-01

    We study the rate at which stars spiral into a massive black hole (MBH) due to the emission of gravitational waves (GWs), as a function of the mass M of the MBH. In the context of our model, it is shown analytically that the rate approximately depends on the MBH mass as M^{-1/4}. Numerical simulations confirm this result, and show that for all MBH masses, the event rate is highest for stellar black holes, followed by white dwarfs, and lowest for neutron stars. The Laser Interferometer Space Antenna (LISA) is expected to see hundreds of these extreme mass ratio inspirals per year. Since the event rate derived here formally diverges as M->0, the model presented here cannot hold for MBHs of masses that are too low, and we discuss what the limitations of the model are.

  9. Sclerostin antibody treatment increases bone formation, bone mass, and bone strength in a rat model of postmenopausal osteoporosis.

    Science.gov (United States)

    Li, Xiaodong; Ominsky, Michael S; Warmington, Kelly S; Morony, Sean; Gong, Jianhua; Cao, Jin; Gao, Yongming; Shalhoub, Victoria; Tipton, Barbara; Haldankar, Raj; Chen, Qing; Winters, Aaron; Boone, Tom; Geng, Zhaopo; Niu, Qing-Tian; Ke, Hua Zhu; Kostenuik, Paul J; Simonet, W Scott; Lacey, David L; Paszty, Chris

    2009-04-01

    The development of bone-rebuilding anabolic agents for potential use in the treatment of bone loss conditions, such as osteoporosis, has been a long-standing goal. Genetic studies in humans and mice have shown that the secreted protein sclerostin is a key negative regulator of bone formation, although the magnitude and extent of sclerostin's role in the control of bone formation in the aging skeleton is still unclear. To study this unexplored area of sclerostin biology and to assess the pharmacologic effects of sclerostin inhibition, we used a cell culture model of bone formation to identify a sclerostin neutralizing monoclonal antibody (Scl-AbII) for testing in an aged ovariectomized rat model of postmenopausal osteoporosis. Six-month-old female rats were ovariectomized and left untreated for 1 yr to allow for significant estrogen deficiency-induced bone loss, at which point Scl-AbII was administered for 5 wk. Scl-AbII treatment in these animals had robust anabolic effects, with marked increases in bone formation on trabecular, periosteal, endocortical, and intracortical surfaces. This not only resulted in complete reversal, at several skeletal sites, of the 1 yr of estrogen deficiency-induced bone loss, but also further increased bone mass and bone strength to levels greater than those found in non-ovariectomized control rats. Taken together, these preclinical results establish sclerostin's role as a pivotal negative regulator of bone formation in the aging skeleton and, furthermore, suggest that antibody-mediated inhibition of sclerostin represents a promising new therapeutic approach for the anabolic treatment of bone-related disorders, such as postmenopausal osteoporosis.

  10. Quality of Life Following Amputation or Limb Preservation in Patients with Lower Extremity Bone Sarcoma

    Directory of Open Access Journals (Sweden)

    Gary E Mason

    2013-08-01

    Full Text Available PURPOSE: Although functional differences have been described between patients with lower extremity bone sarcoma with amputation and limb preservation surgery, differences have not clearly been shown between the two groups related to quality of life. The aim of the study was to determine if there is a difference in overall quality of life in lower extremity bone sarcoma survivors related to whether they had an amputation or a limb preservation procedure. PATIENTS AND METHODS: Eighty-two long-term survivors of lower extremity bone sarcoma were studied to make a comparison of the overall quality of life, pain assessment and psychological evaluations in limb preservation and amputation patients. Forty-eight patients with limb preservation and thirty-four patients with amputations were enrolled in the study. Validated psychometric measures including the Quality of Life Questionnaire, the Minnesota Multiphasic Personality Inventory and visual analog scales were utilized.RESULTS: The overall quality of life of patients with limb preservation was significantly higher than patients with amputation (p-value < 0.01. Significant differences were noted in the categories of material well being, job satisfiers and occupational relations. CONCLUSION: The overall quality of life of patients with limb preservation appears to be better than for those patients with amputation based on the quality of life questionnaire in patients surviving lower extremity bone sarcoma. Further analysis needs to verify the results and focus on the categories that significantly affect the overall quality of life.

  11. Augmented kludge waveforms for detecting extreme-mass-ratio inspirals

    Science.gov (United States)

    Chua, Alvin J. K.; Moore, Christopher J.; Gair, Jonathan R.

    2017-08-01

    The extreme-mass-ratio inspirals (EMRIs) of stellar-mass compact objects into massive black holes are an important class of source for the future space-based gravitational-wave detector LISA. Detecting signals from EMRIs will require waveform models that are both accurate and computationally efficient. In this paper, we present the latest implementation of an augmented analytic kludge (AAK) model, publicly available at https://github.com/alvincjk/EMRI_Kludge_Suite as part of an EMRI waveform software suite. This version of the AAK model has improved accuracy compared to its predecessors, with two-month waveform overlaps against a more accurate fiducial model exceeding 0.97 for a generic range of sources; it also generates waveforms 5-15 times faster than the fiducial model. The AAK model is well suited for scoping out data analysis issues in the upcoming round of mock LISA data challenges. A simple analytic argument shows that it might even be viable for detecting EMRIs with LISA through a semicoherent template bank method, while the use of the original analytic kludge in the same approach will result in around 90% fewer detections.

  12. Ergonomic task reduction prevents bone osteopenia in a rat model of upper extremity overuse.

    Science.gov (United States)

    Barbe, Mary F; Jain, Nisha X; Massicotte, Vicky S; Popoff, Steven N; Barr-Gillespie, Ann E

    2015-01-01

    We evaluated the effectiveness of ergonomic workload reduction of switching rats from a high repetition high force (HRHF) lever pulling task to a reduced force and reach rate task for preventing task-induced osteopenic changes in distal forelimb bones. Distal radius and ulna trabecular structure was examined in young adult rats performing one of three handle-pulling tasks for 12 wk: (1) HRHF, (2) low repetition low force (LRLF); or (3) HRHF for 4 wk and than LRLF thereafter (HRHF-to-LRLF). Results were compared to age-matched controls rats. Distal forelimb bones of 12-wk HRHF rats showed increased trabecular resorption and decreased volume, as control rats. HRHF-to-LRLF rats had similar trabecular bone quality as control rats; and decreased bone resorption (decreased trabecular bone volume and serum CTX1), increased bone formation (increased mineral apposition, bone formation rate, and serum osteocalcin), and decreased osteoclasts and inflammatory cytokines, than HRHF rats. Thus, an ergonomic intervention of HRHF-to-LRLF prevented loss of trabecular bone volume occurring with prolonged performance of a repetitive upper extremity task. These findings support the idea of reduced workload as an effective approach to management of work-related musculoskeletal disorders, and begin to define reach rate and load level boundaries for such interventions.

  13. Bone Mass in Young Adults with down Syndrome

    Science.gov (United States)

    Guijarro, M.; Valero, C.; Paule, B.; Gonzalez-Macias, J.; Riancho, J. A.

    2008-01-01

    Background: Down syndrome (DS) is a frequent cause of intellectual disability. With the increasing life expectancy of these patients, concerns have been raised about the risk of osteoporosis. In fact, several investigators have reported a reduced bone mass in DS. However, the results may be confounded by comorbid diseases, and differences in…

  14. High-fat Diet Decreases Cancellous Bone Mass But Has No Effect on Cortical Bone Mass in the Tibia in Mice

    Science.gov (United States)

    Introduction: Body mass has a positive effect on bone mineral density and the strength. Whether mass derived from an obesity condition is beneficial to bone has not been established; neither have the mechanism by which obesity affects bone metabolism. The aim of this study was to examine the effects...

  15. Clinicopathological features and treatment of extremity bone metastasis in patients with endometrial carcinoma: a case report and review

    Institute of Scientific and Technical Information of China (English)

    JIANG Guo-qing; GAO Yu-nong; GAO Min; ZHENG Hong; YAN Xin; WANG Wen; AN Na; CAO Kun

    2011-01-01

    Unlike other non-gynecologic solid tumors, such as breast cancer, lung cancer, metastasis to bone from endometrial carcinoma is rare, metastasis to extremity is extremely rare. We report a 51-year-old multiparous woman with FIGO Stage IVb Grade 2 endometrial adenocarcinoma which metastasized to left lower extremity bone. She received an amputation of left lower extremity below the knees, and a total abdominal hysterectomy and bilateral salpingo-oophorectomy, and followed by systemic chemotherapy, radiation therapy to the pelvis and progestational agent. She had a complete response to above treatments, and disease-free survival for 10 months. After recurrence, she received chemotherapy, radiotherapy and progestational agent once again. She had lived 56 months and is still alive by the time of report. Metastasis of endometrial carcinoma to extremity bone can rarely occur and should be considered when the patient with endometrial carcinoma complained of unexplained pain and swelling associated with extremity bone.

  16. Effect of Teriparatide, Vibration and the Combination on Bone Mass and Bone Architecture in Chronic Spinal Cord Injury

    Science.gov (United States)

    2014-10-01

    Spinal Cord Injury Effect of Teriparatide, Vibration and the Combination on Bone Mass and Bone Architechture in Chronic... Spinal Cord Injury 5a. CONTRACT NUMBER W81XWH-10-1-0951 Mass and Bone Architecture in Chronic Spinal Cord Injury 5b. GRANT NUMBER 5c. PROGRAM...distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Severe bone loss commonly occurs in individuals with chronic spinal cord injury who are

  17. An approach for determining quantitative measures for bone volume and bone mass in the pediatric spina bifida population.

    Science.gov (United States)

    Horenstein, Rachel E; Shefelbine, Sandra J; Mueske, Nicole M; Fisher, Carissa L; Wren, Tishya A L

    2015-08-01

    The pediatric spina bifida population suffers from decreased mobility and recurrent fractures. This study aimed to develop a method for quantifying bone mass along the entire tibia in youth with spina bifida. This will provide information about all potential sites of bone deficiencies. Computed tomography images of the tibia for 257 children (n=80 ambulatory spina bifida, n=10 non-ambulatory spina bifida, n=167 typically developing) were analyzed. Bone area was calculated at regular intervals along the entire tibia length and then weighted by calibrated pixel intensity for density weighted bone area. Integrals of density weighted bone area were used to quantify bone mass in the proximal and distal epiphyses and diaphysis. Group differences were evaluated using analysis of variance. Non-ambulatory children suffer from decreased bone mass in the diaphysis and proximal and distal epiphyses compared to ambulatory and control children (P≤0.001). Ambulatory children with spina bifida showed statistically insignificant differences in bone mass in comparison to typically developing children at these sites (P>0.5). This method provides insight into tibial bone mass distribution in the pediatric spina bifida population by incorporating information along the whole length of the bone, thereby providing more information than dual-energy x-ray absorptiometry and peripheral quantitative computed tomography. This method can be applied to any population to assess bone mass distribution across the length of any long bone. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Exploration of Extreme Mass Ratio Inspirals with a Tree Code

    Science.gov (United States)

    Miller, Michael

    Extreme mass ratio inspirals (EMRIs), in which a stellar-mass object spirals into a supermassive black hole, are critical gravitational wave sources for the Laser Interferometer Space Antenna (LISA) because of their potential as precise probes of strong gravity. They are although thought to contribute to the flares observed in a few active galactic nuclei that have been attributed to tidal disruption of stars. There are, however, large uncertainties about the rates and properties of EMRIs. The reason is that their galactic nuclear environments contain millions of stars around a central massive object, and their paths must be integrated with great precision to include properly effects such as secular resonances, which accumulate over many orbits. Progress is being made on all fronts, but current numerical options are either profoundly computationally intensive (direct N-body integrators, which in addition do not currently have the needed long-term accuracy) or require special symmetry or other simplifications that may compromise the realism of the results (Monte Carlo and Fokker-Planck codes). We propose to undertake extensive simulations of EMRIs using tree codes that we have adapted to the problem. Tree codes are much faster than direct N-body simulations, yet they are powerful and flexible enough to include nonideal physics such as triaxiality, arbitrary mass spectra, post-Newtonian corrections, and secular evolutionary effects such as resonant relaxation and Kozai oscillations to the equations of motion. We propose to extend our codes to include these effects and to allow separate tracking of special ? that will represent binaries, thus allowing us to follow their interactions and evolution. In our development we will compare our results for a few tens of thousands of particles with a state of the art direct N-body integrator, to evaluate the accuracy of our code and discern systematic effects. This will allow detailed yet fast examinations of large-N systems

  19. Bone mass and bone quality are altered by hypoactivity in the chicken.

    Directory of Open Access Journals (Sweden)

    Eric Aguado

    Full Text Available Disuse induces a rapid bone loss in adults; sedentarity is now recognized as a risk factor for osteoporosis. Hypoactivity or confinement also decrease bone mass in adults but their effects are largely unknown and only few animal models have been described. We have used 10 chickens of the rapidly growing strain 857K bred in a large enclosure (FREE group; 10 others were confined in small cages with little space to move around (HYPO group. They were sacrificed at 53 days and femurs and tibias were evaluated by texture analysis, dual energy X-ray densitometry, microcomputed tomography (microCT and histomorphometry. Hypoactivity had no effect on the length and diameter of the bones. Bone mineral density (BMD, microCT (trabecular bone volume and trabecular microarchitecture and texture analysis were always found significantly reduced in the animals of the HYPO group. BMD was reduced at both femur and tibia diaphysises; BMD of the metaphysis was significantly reduced in the femur but not in the tibia. An increase in osteoid volume and surfaces was noted in the HYPO group. However, there was no alteration of the mineral phase as the osteoid thickness did not differ from control animals. Bone loss was much more pronounced at the lower femur metaphysis than at the upper metaphysis of the tibia. At the tibia, only microarchitectural changes of trabecular bone could be evidenced. The confined chicken represents a new method for the study of hypodynamia since these animals do not have surgical lesions.

  20. Monosodium glutamate-sensitive hypothalamic neurons contribute to the control of bone mass

    Science.gov (United States)

    Elefteriou, Florent; Takeda, Shu; Liu, Xiuyun; Armstrong, Dawna; Karsenty, Gerard

    2003-01-01

    Using chemical lesioning we previously identified hypothalamic neurons that are required for leptin antiosteogenic function. In the course of these studies we observed that destruction of neurons sensitive to monosodium glutamate (MSG) in arcuate nuclei did not affect bone mass. However MSG treatment leads to hypogonadism, a condition inducing bone loss. Therefore the normal bone mass of MSG-treated mice suggested that MSG-sensitive neurons may be implicated in the control of bone mass. To test this hypothesis we assessed bone resorption and bone formation parameters in MSG-treated mice. We show here that MSG-treated mice display the expected increase in bone resorption and that their normal bone mass is due to a concomitant increase in bone formation. Correction of MSG-induced hypogonadism by physiological doses of estradiol corrected the abnormal bone resorptive activity in MSG-treated mice and uncovered their high bone mass phenotype. Because neuropeptide Y (NPY) is highly expressed in MSG-sensitive neurons we tested whether NPY regulates bone formation. Surprisingly, NPY-deficient mice had a normal bone mass. This study reveals that distinct populations of hypothalamic neurons are involved in the control of bone mass and demonstrates that MSG-sensitive neurons control bone formation in a leptin-independent manner. It also indicates that NPY deficiency does not affect bone mass.

  1. Final Report: Bone Mass Inheritance: A Project to Identify the Genetic Regulation of Bone Mass

    Energy Technology Data Exchange (ETDEWEB)

    Recker, Robert R., M.D.

    2002-03-28

    This project was designed to find human chromosomal locations that contain genes regulating peak bone density. It is part of a whole genome search for those loci,each responsible for at least 15% of the variation in the peak adult bone density. We accomplished this with a sib pair design, combined with simultaneous examination of extended kindreds. This project gave partial support of the recruitment which has now been completed. The project will extend into 2003. During the remainder of the project, a whole genome scan will be performed from the entire cohort of 2226 persons who have DNA archived, followed by linkage analysis. This project will meet the scientific objective leading eventually to expanded options for treating the condition that leads to bone thinning osteoporosis, and potential fractures in aging populations.

  2. Detection of rheumatoid arthritis bone erosions by two different dedicated extremity MRI units and conventional radiography

    DEFF Research Database (Denmark)

    Duer-Jensen, A.; Vestergaard, A.; Dohn, U.M.

    2008-01-01

    Objectives: To compare the ability of two different dedicated extremity MRI (E-MRI) units and conventional radiography (CR) for identifying bone erosions in rheumatoid arthritis (RA) metacarpophalangeal (MCP) and wrist joints. Methods: CR and two MRI examinations (using 0.2 T Esaote Artoscan and 0.......2 T portable MagneVu MV1000 units) of 418 bones in the dominant wrist and second to fifth MCP joints of 15 patients with RA and 4 healthy controls were performed and evaluated blindly for bones being visible and for erosions. Results: In MCP joints, MagneVu visualised 18.5% of bones entirely and 71...... with erosions in wrist joints, respectively. With the previously validated Artoscan unit as standard reference, MagneVu and CR had sensitivities of 0.82 and 0.55, respectively, in MCP joint bones and 0.41 and 0.14 in wrist bones. Specificities of CR and MagneVu were comparable (0.82-0.99). The MagneVu unit...

  3. Regional placement of bone mineral mass, fat mass, and lean soft tissue mass in young adult rugby union players.

    Science.gov (United States)

    Bell, W; Evans, W D; Cobner, D M; Eston, R G

    The purpose of the present study was to ascertain whether differences existed in the regional placement of bone mineral mass (BMM), fat mass (FM) and lean soft tissue mass (LSTM) between playing units in Rugby Union Football and between players and control subjects. Thirty young adult rugby players and 21 controls participated in the study. Players were assigned to groups as either forwards (n = 15) or backs (n = 15). Control subjects were matched (n = 15) to rugby players using the mean BMI of forwards and backs. BMM, FM and LSTM were measured using dual-energy X-ray absorptiometry. The digital image of each subject was partitioned into regional anatomical segments comprising the head, right and left arms, trunk, and right and left legs. Measurements were summed for the arms and legs respectively. One-way ANOVA was used to differentiate between- and within-groups; Tukey's post-hoc test was applied to identify pairwise differences. The alpha level was set throughout at p = 0.01. Principal components analysis was utilized to contrast the regional segments of each tissue in each of the groups. Forwards exhibited larger absolute (kg) amounts of BMM, FM and LSTM than backs or controls. In relative terms (%) there were no significant differences in BMM(%) between forwards, backs and controls in the arms and legs, but differences did occur between backs and controls at the trunk (2.9 vs. 2.5%). Backs had a significantly larger LSTM(%) than forwards at the arms (84.4 vs. 76.5%), legs (80.0 vs. 71.9%) and trunk (89.2 vs. 79.0%), whereas forwards had a greater FM(%) than backs at the arms (18.7 vs. 10.6%), legs (23.1 vs. 14.7%), and trunk (18.4 vs. 8.0%). The distribution of BMM showed a lower body-upper body contrast in forwards, a trunk-extremity contrast in backs and an arm-lower body contrast in controls. FM exhibited a trunk-extremity contrast in all three groups, while LSTM displayed an arm-lower body contrast in all three groups. It is concluded that there are

  4. Genome-wide association study using extreme truncate selection identifies novel genes affecting bone mineral density and fracture risk.

    Directory of Open Access Journals (Sweden)

    Emma L Duncan

    2011-04-01

    Full Text Available Osteoporotic fracture is a major cause of morbidity and mortality worldwide. Low bone mineral density (BMD is a major predisposing factor to fracture and is known to be highly heritable. Site-, gender-, and age-specific genetic effects on BMD are thought to be significant, but have largely not been considered in the design of genome-wide association studies (GWAS of BMD to date. We report here a GWAS using a novel study design focusing on women of a specific age (postmenopausal women, age 55-85 years, with either extreme high or low hip BMD (age- and gender-adjusted BMD z-scores of +1.5 to +4.0, n = 1055, or -4.0 to -1.5, n = 900, with replication in cohorts of women drawn from the general population (n = 20,898. The study replicates 21 of 26 known BMD-associated genes. Additionally, we report suggestive association of a further six new genetic associations in or around the genes CLCN7, GALNT3, IBSP, LTBP3, RSPO3, and SOX4, with replication in two independent datasets. A novel mouse model with a loss-of-function mutation in GALNT3 is also reported, which has high bone mass, supporting the involvement of this gene in BMD determination. In addition to identifying further genes associated with BMD, this study confirms the efficiency of extreme-truncate selection designs for quantitative trait association studies.

  5. Effect of nasal salmon calcitonin on bone remodeling and bone mass in postmenopausal osteoporosis.

    Science.gov (United States)

    Thamsborg, G; Jensen, J E; Kollerup, G; Hauge, E M; Melsen, F; Sorensen, O H

    1996-02-01

    The effect of nasal salmon calcitonin (SCT) on bone has been investigated by densitometry, biochemical markers of bone turnover, and histomorphometry. 62 women (mean age 65 years) who had experienced Colles' fracture after menopause were randomized to receive either nasal salmon calcitonin (SCT) 200 IU or nasal placebo daily for 24 months. All received a daily supplement of 0.5 g calcium. There was a significant increase above baseline in the bone mineral density of the lumbar spine in the SCT group (2.5%; 95% confidence interval 0.9--4.2%) and in the placebo group (1.7%; 95% confidence interval 0.3--3.1%) after 24 months, but the difference between the groups was not significant (0.8%; 95% confidence interval -1.2-3.0%). Serum levels of osteocalcin decreased significantly below baseline in the SCT group, whereas they were unchanged in the placebo group. At months 12 and 24, serum levels of osteocalcin were significantly lower in the SCT group than in the placebo group (p transient decrease was observed in the placebo group. The differences between the groups were, however, not significant. The erosion depth was significantly lower in the SCT group than in the placebo group after 12 months (median [interquartile range]; 46.9 mu m [10.4] vs. 50.5 mu m [10.7]; p = 0.03), whereas bone volume and activation frequency did not differ between the groups. This study indicates that nasal SCT in a dose of 200 IU daily induces only a minor inhibition of bone resorption and therefore produces only a minor increase in bone mass. Furthermore, it seems that nasal SCT in a dose of 200 IU does not interfere with the recruitment of new bone multicellular units, but preferably decreases ongoing osteoclastic bone resorption.

  6. Foot Bone in Vivo: Its Center of Mass and Centroid of Shape

    CERN Document Server

    Fan, Yifang; Fan, Yubo; Lin, Zhiyu; Lv, Changsheng

    2010-01-01

    This paper studies foot bone geometrical shape and its mass distribution and establishes an assessment method of bone strength. Using spiral CT scanning, with an accuracy of sub-millimeter, we analyze the data of 384 pieces of foot bones in vivo and investigate the relationship between the bone's external shape and internal structure. This analysis is explored on the bases of the bone's center of mass and its centroid of shape. We observe the phenomenon of superposition of center of mass and centroid of shape fairly precisely, indicating a possible appearance of biomechanical organism. We investigate two aspects of the geometrical shape, (i) distance between compact bone's centroid of shape and that of the bone and (ii) the mean radius of the same density bone issue relative to the bone's centroid of shape. These quantities are used to interpret the influence of different physical exercises imposed on bone strength, thereby contributing to an alternate assessment technique to bone strength.

  7. Deletion of FGFR3 in Osteoclast Lineage Cells Results in Increased Bone Mass in Mice by Inhibiting Osteoclastic Bone Resorption.

    Science.gov (United States)

    Su, Nan; Li, Xiaogang; Tang, Yubin; Yang, Jing; Wen, Xuan; Guo, Jingyuan; Tang, Junzhou; Du, Xiaolan; Chen, Lin

    2016-09-01

    Fibroblast growth factor receptor 3 (FGFR3) participates in bone remodeling. Both Fgfr3 global knockout and activated mice showed decreased bone mass with increased osteoclast formation or bone resorption activity. To clarify the direct effect of FGFR3 on osteoclasts, we specifically deleted Fgfr3 in osteoclast lineage cells. Adult mice with Fgfr3 deficiency in osteoclast lineage cells (mutant [MUT]) showed increased bone mass. In a drilled-hole defect model, the bone remodeling of the holed area in cortical bone was also impaired with delayed resorption of residual woven bone in MUT mice. In vitro assay demonstrated that there was no significant difference between the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts derived from wild-type and Fgfr3-deficient bone marrow monocytes, suggesting that FGFR3 had no remarkable effect on osteoclast formation. The bone resorption activity of Fgfr3-deficient osteoclasts was markedly decreased accompanying with downregulated expressions of Trap, Ctsk, and Mmp 9. The upregulated activity of osteoclastic bone resorption by FGF2 in vitro was also impaired in Fgfr3-deficient osteoclasts, indicating that FGFR3 may participate in the regulation of bone resorption activity of osteoclasts by FGF2. Reduced adhesion but not migration in osteoclasts with Fgfr3 deficiency may be responsible for the impaired bone resorption activity. Our study for the first time genetically shows the direct positive regulation of FGFR3 on osteoclastic bone resorption. © 2016 American Society for Bone and Mineral Research.

  8. The Rho-GEF Kalirin regulates bone mass and the function of osteoblasts and osteoclasts

    OpenAIRE

    2013-01-01

    Bone homeostasis is maintained by the balance between bone resorption by osteoclasts and bone formation by osteoblasts. Dysregulation in the activity of the bone cells can lead to osteoporosis, a disease characterized by low bone mass and an increase in bone fragility and risk of fracture. Kalirin is a novel GTP-exchange factor protein that has been shown to play a role in cytoskeletal remodeling and dendritic spine formation in neurons. We examined Kalirin expression in skeletal tissue and f...

  9. Lean mass appears to be more strongly associated with bone health than fat mass in urban black South African women

    NARCIS (Netherlands)

    Sotunde, O.F.; Kruger, H.S.; Wright, H.H.; Havemann-Nel, L.; Kruger, Ina; Wentzel-Viljoen, E.; Kruger, A.; Tieland, M.

    2015-01-01

    Objectives: To examine the association between body composition (fat mass, lean mass and body mass index, BMI) and bone health (bone mineral density, BMD and fracture risk) in urban black South African women. Design: A cross sectional study examining associations between body composition, dietary

  10. Are levels of bone turnover related to lower bone mass of adolescents previously fed a macrobiotic diet?

    NARCIS (Netherlands)

    Parsons, T.J.; Dusseldorp, van M.; Seibel, M.J.; Staveren, van W.A.

    2001-01-01

    Dutch adolescents who consumed a macrobiotic (vegan-type) diet in early life, demonstrate a lower relative bone mass than their omnivorous counterparts. We investigated whether subjects from the macrobiotic group showed signs of catching up with controls in terms of relative bone mass, reflected by

  11. Are levels of bone turnover related to lower bone mass of adolescents previously fed a macrobiotic diet?

    NARCIS (Netherlands)

    Parsons, T.J.; Dusseldorp, van M.; Seibel, M.J.; Staveren, van W.A.

    2001-01-01

    Dutch adolescents who consumed a macrobiotic (vegan-type) diet in early life, demonstrate a lower relative bone mass than their omnivorous counterparts. We investigated whether subjects from the macrobiotic group showed signs of catching up with controls in terms of relative bone mass, reflected by

  12. The Capra Research Program for Modelling Extreme Mass Ratio Inspirals

    Science.gov (United States)

    Thornburg, Jonathan

    2011-02-01

    Suppose a small compact object (black hole or neutron star) of mass m orbits a large black hole of mass M ≫ m. This system emits gravitational waves (GWs) that have a radiation-reaction effect on the particle's motion. EMRIs (extreme-mass-ratio inspirals) of this type will be important GW sources for LISA. To fully analyze these GWs, and to detect weaker sources also present in the LISA data stream, will require highly accurate EMRI GW templates. In this article I outline the ``Capra'' research program to try to model EMRIs and calculate their GWs ab initio, assuming only that m ≪ M and that the Einstein equations hold. Because m ≪ M the timescale for the particle's orbit to shrink is too long for a practical direct numerical integration of the Einstein equations, and because this orbit may be deep in the large black hole's strong-field region, a post-Newtonian approximation would be inaccurate. Instead, we treat the EMRI spacetime as a perturbation of the large black hole's ``background'' (Schwarzschild or Kerr) spacetime and use the methods of black-hole perturbation theory, expanding in the small parameter m/M. The particle's motion can be described either as the result of a radiation-reaction ``self-force'' acting in the background spacetime or as geodesic motion in a perturbed spacetime. Several different lines of reasoning lead to the (same) basic O(m/M) ``MiSaTaQuWa'' equations of motion for the particle. In particular, the MiSaTaQuWa equations can be derived by modelling the particle as either a point particle or a small Schwarzschild black hole. The latter is conceptually elegant, but the former is technically much simpler and (surprisingly for a nonlinear field theory such as general relativity) still yields correct results. Modelling the small body as a point particle, its own field is singular along the particle worldline, so it's difficult to formulate a meaningful ``perturbation'' theory or equations of motion there. Detweiler and Whiting found

  13. Stellar dynamics and extreme-mass ratio inspirals

    CERN Document Server

    Amaro-Seoane, Pau

    2012-01-01

    Nowadays it is well-established that in the centre of the Milky Way a massive black hole (MBH) with a mass of about four million solar masses is lurking. While there is an emerging consensus about the origin and growth of supermassive black holes (with masses larger than a billion solar masses), MBHs with smaller masses such as the one in our galactic centre remain an understudied enigma. The key to understanding these holes, how some of them grow by orders of magnitude in mass is to understand the dynamics of the stars in the galactic neighborhood. Stars and the central MBH chiefly interact through the gradual inspiral of the stars into the MBH due to the emission of gravitational radiation. Also stars produce gases which will be subsequently accreted by the MBH by collisions and disruptions brought about by the strong central tidal field. Such processes can contribute significantly to the mass of the MBH and progress in understanding them requires theoretical work in preparation for future gravitational rad...

  14. Temporal bone chondroblastoma with secondary aneurysmal bone cyst presenting as an intracranial mass with clinical seizure activity.

    Science.gov (United States)

    Stapleton, Christopher J; Walcott, Brian P; Linskey, Katy R; Kahle, Kristopher T; Nahed, Brian V; Asaad, Wael F

    2011-06-01

    Chondroblastomas are rare tumors that characteristically arise from the epiphyseal cartilage of long bones of the immature skeleton. Intracranial involvement is uncommon, though the squamous portion of the temporal bone is preferentially affected due to its cartilaginous origin. Patients with temporal bone chondroblastomas classically present with otologic symptoms, while primary neurological complaints are rare. In this report, we describe a 33 year-old man with a chondroblastoma of the temporal bone and an associated aneurysmal bone cyst constituting a large intracranial mass lesion who presented with new-onset seizure activity. We review issues relevant to the pathology and treatment of these lesions.

  15. Low body mass index is an important risk factor for low bone mass and increased bone loss in early postmenopausal women. Early Postmenopausal Intervention Cohort (EPIC) study group

    DEFF Research Database (Denmark)

    Ravn, Pernille; Cizza, G; Bjarnason, N H;

    1999-01-01

    Thinness (low percentage of body fat, low body mass index [BMI], or low body weight) was evaluated as a risk factor for low bone mineral density (BMD) or increased bone loss in a randomized trial of alendronate for prevention of osteoporosis in recently postmenopausal women with normal bone mass (n...... of fat mass parameters, prevention of postmenopausal osteoporosis can be equally achieved in thinner and heavier women....... (r = -0.12 to -0.15, p treatment effect of alendronate was dependent on these risk factors, the group treated with 5 mg of alendronate was included (n = 403). There were no associations between fat mass parameters and response to alendronate treatment, which...

  16. Bone Marrow Fat Changes After Gastric Bypass Surgery Are Associated With Loss of Bone Mass.

    Science.gov (United States)

    Kim, Tiffany Y; Schwartz, Ann V; Li, Xiaojuan; Xu, Kaipin; Black, Dennis M; Petrenko, Dimitry M; Stewart, Lygia; Rogers, Stanley J; Posselt, Andrew M; Carter, Jonathan T; Shoback, Dolores M; Schafer, Anne L

    2017-08-09

    Bone marrow fat is a unique fat depot that may regulate bone metabolism. Marrow fat is increased in states of low bone mass, severe underweight, and diabetes. However, longitudinal effects of weight loss and improved glucose homeostasis on marrow fat are unclear, as is the relationship between marrow fat and bone mineral density (BMD) changes. We hypothesized that after Roux-en-Y gastric bypass (RYGB) surgery, marrow fat changes are associated with BMD loss. We enrolled 30 obese women, stratified by diabetes status. Before and 6 months after RYGB, we measured BMD by dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) and vertebral marrow fat content by magnetic resonance spectroscopy. At baseline, those with higher marrow fat had lower BMD. Postoperatively, total body fat declined dramatically in all participants. Effects of RYGB on marrow fat differed by diabetes status (p = 0.03). Nondiabetic women showed no significant mean change in marrow fat (+1.8%, 95% confidence interval [CI] -1.8% to +5.4%, p = 0.29), although those who lost more total body fat were more likely to have marrow fat increases (r = -0.70, p = 0.01). In contrast, diabetic women demonstrated a mean marrow fat change of -6.5% (95% CI -13.1% to 0%, p = 0.05). Overall, those with greater improvements in hemoglobin A1c had decreases in marrow fat (r = 0.50, p = 0.01). Increases in IGF-1, a potential mediator of the marrow fat-bone relationship, were associated with marrow fat declines (r = -0.40, p = 0.05). Spinal volumetric BMD decreased by 6.4% ± 5.9% (p fat and BMD changes were negatively associated, such that those with marrow fat increases had more BMD loss at both spine (r = -0.58, p loss may influence marrow fat behavior, and marrow fat may be a determinant of bone metabolism. © 2017 American Society for Bone and Mineral Research. © 2017 American Society for Bone and Mineral Research.

  17. A pediatric bone mass scan has poor ability to predict adult bone mass: a 28-year prospective study in 214 children.

    Science.gov (United States)

    Buttazzoni, Christian; Rosengren, Bjorn E; Tveit, Magnus; Landin, Lennart; Nilsson, Jan-Åke; Karlsson, Magnus K

    2014-02-01

    As the correlation of bone mass from childhood to adulthood is unclear, we conducted a long-term prospective observational study to determine if a pediatric bone mass scan could predict adult bone mass. We measured cortical bone mineral content (BMC [g]), bone mineral density (BMD [g/cm(2)]), and bone width (cm) in the distal forearm by single photon absorptiometry in 120 boys and 94 girls with a mean age of 10 years (range 3-17) and mean 28 years (range 25-29) later. We calculated individual and age-specific bone mass Z scores, using the control cohort included at baseline as reference, and evaluated correlations between the two measurements with Pearson's correlation coefficient. Individual Z scores were also stratified in quartiles to register movements between quartiles from growth to adulthood. BMD Z scores in childhood and adulthood correlated in both boys (r = 0.35, p pediatric bone scan with a value in the lowest quartile had a sensitivity of 48% (95% confidence interval [CI] 27-69%) and a specificity of 76% (95% CI 66-84%) to identify individuals who would remain in the lowest quartile also in adulthood. Childhood forearm BMD explained 12% of the variance in adult BMD in men and 25% in women. A pediatric distal forearm BMD scan has poor ability to predict adult bone mass.

  18. Changes in biochemical markers and bone mass after withdrawal of ibandronate treatment

    DEFF Research Database (Denmark)

    Ravn, Pernille; Christensen, J O; Baumann, M

    1998-01-01

    :527-533;1996). In this study, we analyzed the biochemical markers as predictors of response in bone mass during ibandronate treatment, and report withdrawal data from the last year of the study, when ibandronate was discontinued. The relative change in the biochemical markers was significantly correlated to the response...... the response in bone mass during ibandronate treatment. The bone loss that resumes after withdrawal of ibandronate treatment is of a magnitude similar to that of normal postmenopausal bone loss....

  19. Do floating orbits in extreme mass ratio binary black holes exist?

    CERN Document Server

    Kapadia, Shasvath J; Glampedakis, Kostas

    2013-01-01

    This paper examines the possibility of floating or non-decaying orbits for extreme mass ratio binary black holes. In the adiabatic approximation, valid in the extreme mass ratio case, if the orbital flux lost due to gravitational radiation reaction is compensated for by the orbital flux gained from the spins of the black holes via superradiant scattering (or, equivalently, tidal acceleration) the orbital decay would be stalled, causing the binary to "float". We show that this flux balance is not, in practice, possible for extreme mass ratio binary black holes with circular equatorial orbits; furthermore, adding eccentricity and inclination to the orbits will not significantly change this null result, thus ruling out the possibility of floating orbits for extreme mass ratio binary black holes. We also argue that binaries consisting of material bodies dense and massive enough to generate gravitational waves detectable by any kind of gravitational wave detector are also unlikely to float. Using a multipolar anal...

  20. Evolution and Yields of Extremely Metal Poor Intermediate Mass Stars

    CERN Document Server

    Herwig, Falk

    2004-01-01

    Intermediate mass stellar evolution tracks from the main sequence to the tip of the AGB for five initial masses (2 to 6Msun) and metallicity Z=0.0001 have been computed. The detailed 1D structure and evolution models include exponential overshooting, mass loss and a detailed nucleosynthesis network with updated nuclear reaction rates. The network includes a two-particle heavy neutron sink for approximating neutron density in the He-shell flash. It is shown how the neutron-capture nucleosynthesis is important in models of very low metallicity for the formation of light neutron-heavy species, like sodium or the heavy neon and magnesium isotopes. The models have high resolution, as required for modeling the third dredge-up. All sequences have been followed from the pre-main sequence to the end of the AGB when all envelope mass is lost. Detailed structural and chemical model properties as well as yields are presented. This set of stellar models is based on standard assumptions and updated input physics. It can be...

  1. Bone multicentric epithelioid hemangioendothelioma of the lower and upper extremities with pulmonary metastases: A case report

    Science.gov (United States)

    ZHANG, HUA; FU, YANBIAO; YE, ZHAOMING

    2015-01-01

    The present study reports a rare case of bone multicentric epithelioid hemangioendothelioma (EH) involving the upper and lower extremities simultaneously, with visceral involvement of the lung. Osteolytic lesions were first identified in the right distal femur and proximal tibia. Slight increased radionuclide uptake was observed in the right shoulder joint on bone scintigraphy, however, this was ignored, as no clinical symptoms were present. The patient was initially misdiagnosed with multifocal chondroblastoma, and an extra-articular curettage of lesions was performed in the proximal tibia and medial femoral condyle, which was filled with bone cement. The histopathological diagnosis was corrected post-operatively following immunohistochemical analysis, which indicated EH, and subsequently, an amputation of the right leg at thigh level was performed. In addition, multiple lytic lesions in the right shoulder joint and pulmonary metastases were identified on whole-body radiological examination. Radiotherapy was administered to the right shoulder joint, however, the patient refused chemotherapy or further surgery. At 15 months after the initial surgery, the patient currently remains alive. This case indicates that an improved understanding with regard to the clinical features of this disease may prevent misdiagnosis and improve EH treatment. PMID:26137035

  2. Small body size and extreme cortical bone remodeling indicate phyletic dwarfism in Magyarosaurus dacus (Sauropoda: Titanosauria).

    Science.gov (United States)

    Stein, Koen; Csiki, Zoltan; Rogers, Kristina Curry; Weishampel, David B; Redelstorff, Ragna; Carballido, Jose L; Sander, P Martin

    2010-05-18

    Sauropods were the largest terrestrial tetrapods (>10(5) kg) in Earth's history and grew at rates that rival those of extant mammals. Magyarosaurus dacus, a titanosaurian sauropod from the Upper Cretaceous (Maastrichtian) of Romania, is known exclusively from small individuals (dwarfism (phyletic nanism) in dinosaurs, but a recent study suggested that the small Romanian titanosaurs actually represent juveniles of a larger-bodied taxon. Here we present strong histological evidence that M. dacus was indeed a dwarf (phyletic nanoid). Bone histological analysis of an ontogenetic series of Magyarosaurus limb bones indicates that even the smallest Magyarosaurus specimens exhibit a bone microstructure identical to fully mature or old individuals of other sauropod taxa. Comparison of histologies with large-bodied sauropods suggests that Magyarosaurus had an extremely reduced growth rate, but had retained high basal metabolic rates typical for sauropods. The uniquely decreased growth rate and diminutive body size in Magyarosaurus were adaptations to life on a Cretaceous island and show that sauropod dinosaurs were not exempt from general ecological principles limiting body size.

  3. A Pediatric Bone Mass Scan has Poor Ability to Predict Peak Bone Mass: An 11-Year Prospective Study in 121 Children.

    Science.gov (United States)

    Buttazzoni, Christian; Rosengren, Bjorn E; Karlsson, Caroline; Dencker, Magnus; Nilsson, Jan-Åke; Karlsson, Magnus K

    2015-05-01

    This 11-year prospective longitudinal study examined how a pre-pubertal pediatric bone mass scan predicts peak bone mass. We measured bone mineral content (BMC; g), bone mineral density (BMD; g/cm(2)), and bone area (cm(2)) in femoral neck, total body and lumbar spine by dual-energy X-ray absorptiometry in a population-based cohort including 65 boys and 56 girls. At baseline all participants were pre-pubertal with a mean age of 8 years (range 6-9), they were re-measured at a mean 11 years (range 10-12) later. The participants were then mean 19 years (range 18-19), an age range that corresponds to peak bone mass in femoral neck in our population. We calculated individual BMC, BMD, and bone size Z scores, using all participants at each measurement as reference and evaluated correlations between the two measurements. Individual Z scores were also stratified in quartiles to register movements between quartiles from pre-pubertal age to peak bone mass. The correlation coefficients (r) between pre-pubertal and young adulthood measurements for femoral neck BMC, BMD, and bone area varied between 0.37 and 0.65. The reached BMC value at age 8 years explained 42 % of the variance in the BMC peak value; the corresponding values for BMD were 31 % and bone area 14 %. Among the participants with femoral neck BMD in the lowest childhood quartile, 52 % had left this quartile at peak bone mass. A pediatric bone scan with a femoral neck BMD value in the lowest quartile had a sensitivity of 47 % [95 % confidence interval (CI) 28, 66] and a specificity of 82 % (95 % CI 72, 89) to identify individuals who would remain in the lowest quartile at peak bone mass. The pre-pubertal femoral neck BMD explained only 31 % of the variance in femoral neck peak bone mass. A pre-pubertal BMD scan in a population-based sample has poor ability to predict individuals who are at risk of low peak bone mass.

  4. Progress Towards a Quantum Degenerate Mixture with Extreme Mass Imbalance

    Science.gov (United States)

    Desalvo, B. J.; Johansen, Jacob; Chin, Cheng

    2016-05-01

    We report experimental progress towards a quantum degenerate Bose-Fermi mixture of 133 Cs and 6 Li. Beyond providing the largest mass imbalance of any bi-alkali mixture, this system exhibits multiple interspecies Feshbach resonances allowing wide tuning of the interaction strength and Efimov resonances potentially inducing three-body interactions. The use of a dual-color optical dipole trap in our experiment overcomes the large differential gravitational sag due to the mass imbalance and facilitates mixing the species nano-Kelvin temperatures allowing precision studies of interspecies interactions. Turning from few-body physics to many-body, we will present our efforts to reach simultaneous quantum degeneracy as well as discuss prospects of high resolution imaging of both species.

  5. BMP signaling negatively regulates bone mass through sclerostin by inhibiting the canonical Wnt pathway.

    Science.gov (United States)

    Kamiya, Nobuhiro; Ye, Ling; Kobayashi, Tatsuya; Mochida, Yoshiyuki; Yamauchi, Mitsuo; Kronenberg, Henry M; Feng, Jian Q; Mishina, Yuji

    2008-11-01

    Bone morphogenetic proteins (BMPs) are known to induce ectopic bone. However, it is largely unknown how BMP signaling in osteoblasts directly regulates endogenous bone. This study investigated the mechanism by which BMP signaling through the type IA receptor (BMPR1A) regulates endogenous bone mass using an inducible Cre-loxP system. When BMPR1A in osteoblasts was conditionally disrupted during embryonic bone development, bone mass surprisingly was increased with upregulation of canonical Wnt signaling. Although levels of bone formation markers were modestly reduced, levels of resorption markers representing osteoclastogenesis were severely reduced, resulting in a net increase in bone mass. The reduction of osteoclastogenesis was primarily caused by Bmpr1a-deficiency in osteoblasts, at least through the RANKL-OPG pathway. Sclerostin (Sost) expression was downregulated by about 90% and SOST protein was undetectable in osteoblasts and osteocytes, whereas the Wnt signaling was upregulated. Treatment of Bmpr1a-deficient calvariae with sclerostin repressed the Wnt signaling and restored normal bone morphology. By gain of Smad-dependent BMPR1A signaling in mice, Sost expression was upregulated and osteoclastogenesis was increased. Finally, the Bmpr1a-deficient bone phenotype was rescued by enhancing BMPR1A signaling, with restoration of osteoclastogenesis. These findings demonstrate that BMPR1A signaling in osteoblasts restrain endogenous bone mass directly by upregulating osteoclastogenesis through the RANKL-OPG pathway, or indirectly by downregulating canonical Wnt signaling through sclerostin, a Wnt inhibitor and a bone mass mediator.

  6. One Year of Abaloparatide, a Selective Activator of the PTH1 Receptor, Increased Bone Formation and Bone Mass in Osteopenic Ovariectomized Rats Without Increasing Bone Resorption.

    Science.gov (United States)

    Varela, Aurore; Chouinard, Luc; Lesage, Elisabeth; Smith, Susan Y; Hattersley, Gary

    2017-01-01

    Abaloparatide is a novel 34-amino acid peptide selected to be a potent and selective activator of the parathyroid hormone receptor (PTH1R) signaling pathway with 41% homology to PTH(1-34) and 76% homology to PTHrP(1-34). A 12-month treatment study was conducted in osteopenic ovariectomized (OVX) rats to characterize the mechanisms by which abaloparatide increases bone mass. Sprague-Dawley (SD) rats were subjected to OVX or sham surgery at age 6 months and left untreated for 3 months to allow OVX-induced bone loss. Ten OVX rats were euthanized after this bone depletion period, and the remaining OVX rats received daily subcutaneous injections of vehicle (n = 18) or abaloparatide at 1, 5, or 25 μg/kg/d (n = 18/dose level) for 12 months. Sham controls (n = 18) received vehicle daily. Bone densitometry and biochemical markers of bone formation and resorption were assessed longitudinally, and L3 vertebra and tibia were collected at necropsy for histomorphometry. Abaloparatide increased biochemical bone formation markers without increasing bone resorption markers or causing hypercalcemia. Abaloparatide increased histomorphometric indices of bone formation on trabecular, endocortical, and periosteal surfaces without increasing osteoclasts or eroded surfaces. Abaloparatide induced substantial increases in trabecular bone volume and density and improvements in trabecular microarchitecture. Abaloparatide stimulated periosteal expansion and endocortical bone apposition at the tibial diaphysis, leading to marked increases in cortical bone volume and density. Whole-body bone mineral density (BMD) remained stable in OVX-Vehicle controls while increasing 25% after 12 months of abaloparatide (25 μg/kg). Histomorphometry and biomarker data suggest that gains in cortical and trabecular bone mass were attributable to selective anabolic effects of abaloparatide, without evidence for stimulated bone resorption. © 2016 American Society for Bone and Mineral Research.

  7. The Relation between Visceral and Subcutaneous Fat to Bone Mass among Egyptian Children and Adolescents

    Directory of Open Access Journals (Sweden)

    Sahar A. El-Masry

    2014-12-01

    CONCLUSIONS: Visceral and subcutaneous fat had significant positive association with bone mass in children; males and females respectively. On the contrary such association disappeared during adolescence.

  8. Bone mass in schizophrenia and normal populations across different decades of life

    Directory of Open Access Journals (Sweden)

    Chueh Ching-Mo

    2009-01-01

    Full Text Available Abstract Background Chronic schizophrenic patients have been reported as having higher osteoporosis prevalence. Survey the bone mass among schizophrenic patients and compare with that of the local community population and reported data of the same country to figure out the distribution of bone mass among schizophrenic patients. Methods 965 schizophrenic patients aged 20 years and over in Yuli Veterans Hospital and 405 members aged 20 and over of the community living in the same town as the institute received bone mass examination by a heel qualitative ultrasound (QUS device. Bone mass distribution was stratified to analyzed and compared with community population. Results Schizophrenic patients have lower bone mass while they are young. But aging effect on bone mass cannot be seen. Accelerated bone mass loss during menopausal transition was not observed in the female schizophrenic patients as in the subjects of the community female population. Conclusion Schizophrenic patients have lower bone mass than community population since they are young. Further study to investigate the pathophysiological process is necessary to delay or avoid the lower bone mass in schizophrenia patients.

  9. Contributions of lean mass and fat mass to bone mineral density: a study in postmenopausal women

    Directory of Open Access Journals (Sweden)

    Lai Thai Q

    2010-03-01

    Full Text Available Abstract Background The relative contribution of lean and fat to the determination of bone mineral density (BMD in postmenopausal women is a contentious issue. The present study was undertaken to test the hypothesis that lean mass is a better determinant of BMD than fat mass. Methods This cross-sectional study involved 210 postmenopausal women of Vietnamese background, aged between 50 and 85 years, who were randomly sampled from various districts in Ho Chi Minh City (Vietnam. Whole body scans, femoral neck, and lumbar spine BMD were measured by DXA (QDR 4500, Hologic Inc., Waltham, MA. Lean mass (LM and fat mass (FM were derived from the whole body scan. Furthermore, lean mass index (LMi and fat mass index (FMi were calculated as ratio of LM or FM to body height in metre squared (m2. Results In multiple linear regression analysis, both LM and FM were independent and significant predictors of BMD at the spine and femoral neck. Age, lean mass and fat mass collectively explained 33% variance of lumbar spine and 38% variance of femoral neck BMD. Replacing LM and FM by LMi and LMi did not alter the result. In both analyses, the influence of LM or LMi was greater than FM and FMi. Simulation analysis suggested that a study with 1000 individuals has a 78% chance of finding the significant effects of both LM and FM, and a 22% chance of finding LM alone significant, and zero chance of finding the effect of fat mass alone. Conclusions These data suggest that both lean mass and fat mass are important determinants of BMD. For a given body size -- measured either by lean mass or height --women with greater fat mass have greater BMD.

  10. Bone Mineral Density in Sheehan's Syndrome; Prevalence of Low Bone Mass and Associated Factors.

    Science.gov (United States)

    Chihaoui, Melika; Yazidi, Meriem; Chaker, Fatma; Belouidhnine, Manel; Kanoun, Faouzi; Lamine, Faiza; Ftouhi, Bochra; Sahli, Hela; Slimane, Hedia

    2016-10-01

    Hypopituitarism is a known cause of bone mineral loss. This study aimed to evaluate the frequency of osteopenia and osteoporosis in patients with Sheehan's syndrome (SS) and to determine the risk factors. This is a retrospective study of 60 cases of SS that have had a bone mineral density (BMD) measurement. Clinical, biological, and therapeutic data were collected. The parameters of osteodensitometry at the femoral neck and the lumbar spine of 60 patients with SS were compared with those of 60 age-, height-, and weight-matched control women. The mean age at BMD measurement was 49.4 ± 9.9 yr (range: 25-76 yr). The mean duration of SS was 19.3 ± 8.5 yr (range: 3-41 yr). All patients had corticotropin deficiency and were treated with hydrocortisone at a mean daily dose of 26.3 ± 4.1 mg. Fifty-seven patients (95%) had thyrotropin deficiency and were treated with thyroxine at a mean daily dose of 124.3 ± 47.4 µg. Thirty-five of the 49 patients, aged less than 50 yr at diagnosis and having gonadotropin deficiency (71.4%), had estrogen-progesterone substitution. Osteopenia was present in 25 patients (41.7%) and osteoporosis in 21 (35.0%). The BMD was significantly lower in the group with SS than in the control group (p < 0.001). The odds ratio of osteopenia-osteoporosis was 3.1 (95% confidence interval: 1.4-6.8) at the femoral neck and 3.7 (95% confidence interval: 1.7-7.8) at the lumbar spine. The lumbar spine was more frequently affected by low bone mineral mass (p < 0.05). The duration of the disease and the daily dose of hydrocortisone were independently and inversely associated with BMD at the femoral neck. The daily dose of thyroxine was independently and inversely associated with BMD at the lumbar spine. Estrogen-progesterone replacement therapy was not associated with BMD. Low bone mineral mass was very common in patients with SS. The lumbar spine was more frequently affected. The duration of the disease and the doses of

  11. Regulation of bone mass, osteoclast function, and ovariectomy-induced bone loss by the type 2 cannabinoid receptor.

    Science.gov (United States)

    Idris, Aymen I; Sophocleous, Antonia; Landao-Bassonga, Euphemie; van't Hof, Robert J; Ralston, Stuart H

    2008-11-01

    The endocannabinoid system has recently been shown to play a role in the regulation of bone metabolism. The type 2 cannabinoid receptor (CB2) has been reported to regulate bone mass, but conflicting results have been reported with regard to its effects on bone resorption and osteoclast function. Here we investigated the role that CB2 plays in regulating bone mass and osteoclast function using a combination of pharmacological and genetic approaches. The CB2-selective antagonist/inverse agonist AM630 inhibited osteoclast formation and activity in vitro, whereas the CB2-selective agonists JWH133 and HU308 stimulated osteoclast formation. Osteoclasts generated from CB2 knockout mice (CB2-/-) were resistant to the inhibitory effects of AM630 in vitro, consistent with a CB2-mediated effect. There was no significant difference in peak bone mass between CB2-/- mice and wild-type littermates, but after ovariectomy, bone was lost to a greater extent in wild-type compared with CB2-/- mice. Furthermore, AM630 protected against bone loss in wild-type mice, but the effect was blunted in CB2-/- mice. We conclude that CB2 regulates osteoclast formation and bone resorption in vitro and that under conditions of increased bone turnover, such as after ovariectomy, CB2 regulates bone loss. These observations indicate that CB2 regulates osteoclast formation and contributes to ovariectomy-induced bone loss and demonstrate that cannabinoid receptor antagonists/inverse agonists may be of value in the treatment of bone diseases characterized by increased osteoclast activity.

  12. Regulation of lean mass, bone mass, and exercise tolerance by the central melanocortin system.

    Directory of Open Access Journals (Sweden)

    Theodore P Braun

    Full Text Available Signaling via the type 4-melanocortin receptor (MC4R is an important determinant of body weight in mice and humans, where loss of function mutations lead to significant obesity. Humans with mutations in the MC4R experience an increase in lean mass. However, the simultaneous accrual of fat mass in such individuals may contribute to this effect via mechanical loading. We therefore examined the relationship of fat mass and lean mass in mice lacking the type-4 melanocortin receptor (MC4RKO. We demonstrate that MC4RKO mice display increased lean body mass. Further, this is not dependent on changes in adipose mass, as MC4RKO mice possess more lean body mass than diet-induced obese (DIO wild type mice with equivalent fat mass. To examine potential sources of the increased lean mass in MC4RKO mice, bone mass and strength were examined in MC4RKO mice. Both parameters increase with age in MC4RKO mice, which likely contributes to increases in lean body mass. We functionally characterized the increased lean mass in MC4RKO mice by examining their capacity for treadmill running. MC4R deficiency results in a decrease in exercise performance. No changes in the ratio of oxidative to glycolytic fibers were seen, however MC4RKO mice demonstrate a significantly reduced heart rate, which may underlie their impaired exercise performance. The reduced exercise capacity we report in the MC4RKO mouse has potential clinical ramifications, as efforts to control body weight in humans with melanocortin deficiency may be ineffective due to poor tolerance for physical activity.

  13. Loss of bone mass after Colles' fractrur:a follow-up study

    Institute of Scientific and Technical Information of China (English)

    戴力扬; 蒋雷生

    2004-01-01

    Background Colles' fracture usually associated with osteoporosis is regarded as the predictor of subsequent osteoporotic fracture. However, it is not clear how the local changes of bone mass take place during the course of treatment and whether the changes are related to clinical practice. The objective of the current study was to investigate the local changes of bone mass in patients with Colles' fracture and their possible clinical relevance in a follow-up study.Methods The radiograms of the second metacarpal in 64 patients with Colles' fracture were assessed for bone density immediately after fracture, 6 weeks, 6 months and 1 year after fracture, respectively. Functional results were evaluated at one year.Results Bone mass six weeks after Colles' fracture was significantly decreased without returning to normal at one year though increased bone mass had been identified 6 months after fracture (P< 0.05), (P< 0.01). At one year significant (P< 0.05) or highly significant (P< 0.01) correlations were observed between bone mass indices of metacarpal and functional results, indicating that poor function is associated with lower bone density. Significant differences (P< 0.05) between fracture patterns also suggested that patients with more severe fractures have a more pronounced bone loss.Conclusions Bone loss during the course of treatment will have a direct effect upon the prognosis, so different treatment should be proposed for different patterns of fractures. Active exercise should be made to improve the recovery of bone mass.

  14. Intra-arterial Autologous Bone Marrow Cell Transplantation in a Patient with Upper-extremity Critical Limb Ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Madaric, Juraj, E-mail: jurmad@hotmail.com [National Institute of Cardiovascular Diseases (NUSCH) and Slovak Medical University, Department of Cardiology and Angiology (Slovakia); Klepanec, Andrej [National Institute of Cardiovascular Diseases, Department of Diagnostic and Interventional Radiology (Slovakia); Mistrik, Martin [Clinic of Hematology and Transfusiology, Faculty Hospital (Slovakia); Altaner, Cestmir [Slovak Academy of Science, Institute of Experimental Oncology (Slovakia); Vulev, Ivan [National Institute of Cardiovascular Diseases, Department of Diagnostic and Interventional Radiology (Slovakia)

    2013-04-15

    Induction of therapeutic angiogenesis by autologous bone marrow mononuclear cell transplantation has been identified as a potential new option in patients with advanced lower-limb ischemia. There is little evidence of the benefit of intra-arterial cell application in upper-limb critical ischemia. We describe a patient with upper-extremity critical limb ischemia with digital gangrene resulting from hypothenar hammer syndrome successfully treated by intra-arterial autologous bone marrow mononuclear cell transplantation.

  15. An altered hormonal profile and elevated rate of bone loss are associated with low bone mass in professional horse-racing jockeys.

    Science.gov (United States)

    Dolan, Eimear; McGoldrick, Adrian; Davenport, Colin; Kelleher, Grainne; Byrne, Brendan; Tormey, William; Smith, Diarmuid; Warrington, Giles D

    2012-09-01

    Horse-racing jockeys are a group of weight-restricted athletes, who have been suggested as undertaking rapid and extreme weight cycling practices in order to comply with stipulated body-mass standards. The aim of this study was to examine bone mass, turnover and endocrine function in jockeys and to compare this group with age, gender and body mass index matched controls. Twenty male professional jockeys and 20 healthy male controls participated. Dual energy X-ray absorptiometry scans and early morning fasting blood and urine samples were used to measure bone mass, turnover and a hormonal profile. Total body bone mineral density (BMD) was significantly lower in jockeys (1.143 ± 0.05 vs. 1.27 ± 0.06 g cm(-3), p < 0.01). Bone resorptive activity was elevated in the jockey group as indicated by significantly higher urinary NTx/creatinine (76.94 ± 29.52 vs. 55.9 ± 13.9 nmol mmol(-1), p < 0.01), resulting in a significantly negative uncoupling index between bone resorption and formation. Sex hormone binding globulin (SHBG) levels were significantly higher in jockeys (41.21 ± 9.77 vs. 28.24 ± 9.98 nmol L(-1), p < 0.01) with a lower percentage of bioavailable testosterone (48.89 ± 7.38 vs. 59.18 ± 6.74 %, p < 0.01). SHBG and insulin-like growth factor-1 were independent predictors of total body and femoral neck BMD, respectively (p < 0.05). In conclusion, it appears that professional jockeys have an elevated rate of bone loss and reduced bone mass that appears to be associated with disrupted hormonal activity. It is likely that this may have occurred in response to the chronic weight cycling habitually experienced by this group.

  16. Proximal location in extremity long bones is a poor prognostic factor for osteosarcoma: A retrospective cohort study of 153 patients.

    Science.gov (United States)

    Cates, Justin M M; Schoenecker, Jonathan G

    2016-08-01

    Osteosarcomas arising in the proximal femur, humerus, and tibia appear to have poorer outcomes than those arising in distal long bones. However, the strength of this association is uncertain, particularly in light of other prognostic factors. Therefore, this retrospective cohort study was performed to compare patient outcomes between proximal and distal tumor location within extremity long bones. A total of 153 patients with conventional high-grade osteosarcoma of the extremity long bones, pelvis, or axial skeleton who had undergone neoadjuvant chemotherapy and surgical resection between 1985 and 2010 were identified in the Surgical Pathology files at Vanderbilt Medical Center. Effect of anatomic location within a proximal long bone was assessed using multivariable Cox proportional hazard regression. Proximal tumor location was a strong predictor of poor prognosis in univariate survival analysis. Multivariate regression analysis showed that after controlling for American Joint Committee on Cancer (AJCC) stage, histologic response to chemotherapy, surgical resection margin status, and histologic type, location in the proximal femur, tibia, and humerus were independent risk factors for death due to osteosarcoma, but not event-free survival. Osteosarcomas of the proximal extremity long bones are associated with decreased disease-specific survival compared to tumors of the distal long bones, even after accounting for other key prognostic covariates.

  17. High fat diet promotes achievement of peak bone mass in young rats

    Energy Technology Data Exchange (ETDEWEB)

    Malvi, Parmanand; Piprode, Vikrant; Chaube, Balkrishna; Pote, Satish T. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Mittal, Monika; Chattopadhyay, Naibedya [Division of Endocrinology and Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Jankipuram Extension, Sitapur Road, Lucknow 226 031 (India); Wani, Mohan R. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Bhat, Manoj Kumar, E-mail: manojkbhat@nccs.res.in [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India)

    2014-12-05

    Highlights: • High fat diet helps in achieving peak bone mass at younger age. • Shifting from high fat to normal diet normalizes obese parameters. • Bone parameters are sustained even after withdrawal of high fat diet. - Abstract: The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (μ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet.

  18. The use of bone allografts for limb salvage in high-grade extremity osteosarcoma.

    Science.gov (United States)

    Gebhardt, M C; Flugstad, D I; Springfield, D S; Mankin, H J

    1991-09-01

    Limb preservation is increasingly being employed in the local treatment of high-grade extremity osteosarcoma. Bone allografts used to reconstruct the bony defects following tumor resection offer many advantages, including joint reconstruction and incorporation of the graft to the host bone in these relatively young patients. The results of 53 patients 30 years of age or younger were assessed to determine functional outcome. Fresh-frozen allografts were employed as osteoarticular grafts, allograft-arthrodeses, allograft-prosthesis composites, or intercalary grafts. Follow-up intervals averaged 25 months (range, two to 63 months). Life-table analysis showed that the probability of a satisfactory functional result was 73% if local tumor recurrences were excluded. Complications included 16 infections, six fractures, 12 nonunions, and six unstable joints. There were five local recurrences. Eighteen grafts ultimately failed, and in six patients, this resulted in an above-knee amputation. An additional five received a second graft. The functional "end results" of the 38 patients with two or more years of follow-up examinations were 70% satisfactory in those without a local recurrence. There was no statistically significant difference in functional outcome or local or distant relapse in those patients receiving preoperative chemotherapy. The authors conclude that allografts can be used for limb reconstruction in patients with high-grade osteosarcoma who receive aggressive adjuvant chemotherapy. The functional results are comparable to other methods of reconstruction, and once incorporated by the host, offer the advantage of longevity, compared with metallic implants.

  19. Parallels between Nutrition and Physical Activity: Research Questions in Development of Peak Bone Mass

    Science.gov (United States)

    Weaver, Connie M.

    2015-01-01

    Lifestyle choices are attributed to 40% to 60% of adult peak bone mass. The National Osteoporosis Foundation (NOF) sought to update its 2000 consensus statement on peak bone mass and partnered with the American Society for Nutrition, which, in turn, charged a 9-member writing committee with using a systematic review approach to update the previous…

  20. Does fetal smoke exposure affect childhood bone mass? The Generation R Study

    NARCIS (Netherlands)

    D.H.M. Heppe (Denise); M.C. Medina-Gomez (Carolina); A. Hofman (Albert); F. Rivadeneira Ramirez (Fernando); V.W.V. Jaddoe (Vincent)

    2015-01-01

    textabstractSummary: We assessed the intrauterine influence of maternal smoking on childhood bone mass by comparing parental prenatal and postnatal smoking habits. We observed higher bone mass in children exposed to maternal smoking, explained by higher body weight. Maternal smoking or related lifes

  1. Parallels between Nutrition and Physical Activity: Research Questions in Development of Peak Bone Mass

    Science.gov (United States)

    Weaver, Connie M.

    2015-01-01

    Lifestyle choices are attributed to 40% to 60% of adult peak bone mass. The National Osteoporosis Foundation (NOF) sought to update its 2000 consensus statement on peak bone mass and partnered with the American Society for Nutrition, which, in turn, charged a 9-member writing committee with using a systematic review approach to update the previous…

  2. Insulin Resistance Is Associated With Smaller Cortical Bone Size in Nondiabetic Men at the Age of Peak Bone Mass.

    Science.gov (United States)

    Verroken, Charlotte; Zmierczak, Hans-Georg; Goemaere, Stefan; Kaufman, Jean-Marc; Lapauw, Bruno

    2017-06-01

    In type 2 diabetes mellitus, fracture risk is increased despite preserved areal bone mineral density. Although this apparent paradox may in part be explained by insulin resistance affecting bone structure and/or material properties, few studies have investigated the association between insulin resistance and bone geometry. We aimed to explore this association in a cohort of nondiabetic men at the age of peak bone mass. Nine hundred ninety-six nondiabetic men aged 25 to 45 years were recruited in a cross-sectional, population-based sibling pair study at a university research center. Insulin resistance was evaluated using the homeostasis model assessment of insulin resistance (HOMA-IR), with insulin and glucose measured from fasting serum samples. Bone geometry was assessed using peripheral quantitative computed tomography at the distal radius and the radial and tibial shafts. In age-, height-, and weight-adjusted analyses, HOMA-IR was inversely associated with trabecular area at the distal radius and with cortical area, periosteal and endosteal circumference, and polar strength strain index at the radial and tibial shafts (β ≤ -0.13, P insulin-like growth factor 1, or sex steroid levels. In this cohort of nondiabetic men at the age of peak bone mass, insulin resistance is inversely associated with trabecular and cortical bone size. These associations persist after adjustment for body composition, muscle size or function, or sex steroid levels, suggesting an independent effect of insulin resistance on bone geometry.

  3. Bone mass in girls according to their BMI, VO2 max, hours and years of practice.

    Science.gov (United States)

    Ubago-Guisado, Esther; Martinez-Rodriguez, Alejandro; Gallardo, Leonor; Sánchez-Sánchez, Javier

    2016-11-01

    The accumulation of bone mass during puberty is related with bone health in adulthood. This accumulation is influenced by diverse factors such as body mass index (BMI), maximal oxygen uptake (VO2 max), hours of training and years of sport practice. For this reason, the objective of this study is to analyse the influence of these variables on bone mass in young female athletes. The sample is formed of 120 healthy girls with ages between 9 and 13 (11.32 ± 1.6 years old), divided into two groups depending on their BMI, VO2 max, hours of training and years of sport practice. The participants completed a series of tests to evaluate level of sexual development, body composition (fat mass, lean mass and bone mass) and physical condition. The results show higher values of total lean mass, total fat mass and percentage of body fat in the groups with higher BMI in prepubertal girls and pubertal girls (p VO2 max, in the prepubertal group, girls with lower VO2 max had higher values of total fat mass (p VO2 max also showed a higher total fat mass (p < .05). The studied variables account for a 85% and 75.4% of the variance of total bone mineral content and bone mineral density (BMD), respectively. In conclusion, the content and BMD are closely related with muscle mass and sports practice in young females. The amount of fat mass showed no association with bone mass and physical condition has an indirect relationship with bone development.

  4. Chronic central administration of Ghrelin increases bone mass through a mechanism independent of appetite regulation.

    Directory of Open Access Journals (Sweden)

    Hyung Jin Choi

    Full Text Available Leptin plays a critical role in the central regulation of bone mass. Ghrelin counteracts leptin. In this study, we investigated the effect of chronic intracerebroventricular administration of ghrelin on bone mass in Sprague-Dawley rats (1.5 μg/day for 21 days. Rats were divided into control, ghrelin ad libitum-fed (ghrelin ad lib-fed, and ghrelin pair-fed groups. Ghrelin intracerebroventricular infusion significantly increased body weight in ghrelin ad lib-fed rats but not in ghrelin pair-fed rats, as compared with control rats. Chronic intracerebroventricular ghrelin infusion significantly increased bone mass in the ghrelin pair-fed group compared with control as indicated by increased bone volume percentage, trabecular thickness, trabecular number and volumetric bone mineral density in tibia trabecular bone. There was no significant difference in trabecular bone mass between the control group and the ghrelin ad-lib fed group. Chronic intracerebroventricular ghrelin infusion significantly increased the mineral apposition rate in the ghrelin pair-fed group as compared with control. In conclusion, chronic central administration of ghrelin increases bone mass through a mechanism that is independent of body weight, suggesting that ghrelin may have a bone anabolic effect through the central nervous system.

  5. The Information Aspect of Extremism and Terrorism and the Destructive Trends in the Mass Media

    Directory of Open Access Journals (Sweden)

    E V Nekrasova

    2013-12-01

    Full Text Available The article is devoted to the problem of destructive trends in modern Russian mass media as well as to the information component in the activities of extremist and terrorist organizations. The destructive trends in the mass media manifest themselves in the escalation of animosity, aggression, creation of the cult of violence and xenophobia moods. Terrorist organizations use the mass media for their own purposes: they create the atmosphere of fear and tension in society, recruit new followers, mainly among the youth, which is a serious problem. It is important to use the positive potential of the mass media to counteract extremism and terrorism.

  6. IGF-1 Signaling is Essential for Differentiation of Mesenchymal Stem Cells for Peak Bone Mass.

    Science.gov (United States)

    Crane, Janet L; Zhao, Luo; Frye, Joseph S; Xian, Lingling; Qiu, Tao; Cao, Xu

    2013-06-01

    Survival of children with chronic medical illnesses is leading to an increase in secondary osteoporosis due to impaired peak bone mass (PBM). Insulin-like growth factor type 1 (IGF-1) levels correlate with the pattern of bone mass accrual and many chronic illnesses are associated with low IGF-1 levels. Reduced serum levels of IGF-1 minimally affect the integrity of the skeleton, whereas recent studies suggest that skeletal IGF-I regulates PBM. To determine the role of IGF-1 in postnatal bone mass accrual regardless of source, we established an inducible type 1 Igf receptor Cre/lox knockout mouse model, in which the type 1 Igf receptor was deleted inducibely in the mesenchymal stem cells (MSCs) from 3-7 weeks of age. The size of the mouse was not affected as knockout and wild type mice had similar body weights and nasoanal and femoral lengths. However, bone volume and trabecular bone thickness were decreased in the secondary spongiosa of female knockout mice relative to wild type controls, indicating that IGF-1 is critical for bone mass. IGF-1 signaling in MSCs in vitro has been implicated to be involved in both migration to the bone surface and differentiation into bone forming osteoblasts. To clarify the exact role of IGF-1 in bone, we found by immunohistochemical analysis that a similar number of Osterix-positive osteoprogenitors were on the bone perimeter, indicating migration of MSCs was not affected. Most importantly, 56% fewer osteocalcin-positive mature osteoblasts were present on the bone perimeter in the secondary spongiosa in knockout mice versus wild type littermates. These in vivo data demonstrate that the primary role of skeletal IGF-1 is for the terminal differentiation of osteoprogenitors, but refute the role of IGF-1 in MSC migration in vivo. Additionally, these findings confirm that impaired IGF-1 signaling in bone MSCs is sufficient to impair bone mass acquisition.

  7. Alendronate has a residual effect on bone mass in postmenopausal Danish women up to 7 years after treatment withdrawal

    DEFF Research Database (Denmark)

    Bagger, Yu Z; Tankó, László B; Alexandersen, Peter

    2003-01-01

    Alendronate has been shown to reduce bone turnover and increase bone mass. However, little is known about the duration of the effect on bone after treatment withdrawal. The aim of this study was to investigate the long-term effects on bone mineral density (BMD) and bone turnover of various alendr...

  8. Structural bone allografts with intramedullary vascularized fibular autografts for the treatment of massive bone defects in extremities

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To report the clinical outcome of repairing massive bone defects biologically in limbs by homeochronous using structural bone allografts with intramedullary vascularized fibular auto-grafts. Methods: From January 2001 to December 2005. large bone defects in 19 patients (11 men and 8 women, aged 6 to 35 years) were repaired by structural bone allografts with intramedullary vascularized fibular autografts in the homeochronous period. The range of the length of bone defects was 11 to 25 cm (mean 17. 6 cm), length of vascularized free fibular was 15 to 29 cm (mean 19. 2 cm), length of massive bone allografts was 11 to 24 cm (mean 17. 1 cm). Location of massive bone defects was in humerus(n = 1), in femur(n = 9) and in tibia(n = 9), respectively. Results: After 9 to 69 months (mean 38. 2 months) follow-up, wounds of donor and recipient sites were healed in Ⅰ stage, monitoring-flaps were alive, eject reaction of massive bone allografts were slight, no complications in donor limbs. Fifteen patients had the evidence of radiographic union 3 to 6 months after surgery, 3 cases united 8 months later, and the remained one case of malignant synovioma in distal femur recurred and amputated the leg 2. 5 months, post-operatively. Five patients had been removed internal fixation, complete bone unions were found one year postoperatively. None of massive bone allografts were absorbed or collapsed at last follow-up. Conclusion: The homeochronous usage of structural bone allograft with an intramedullary vascularized fibular au-tograft can biologically obtain a structure with the immediate mechanical strength of the allograft, a potential result of revascularization through the vascularized fibula, and accelerate bone union not only between fibular autograft and the host but also between massive bone allograft and the host.

  9. The Rho-GEF Kalirin regulates bone mass and the function of osteoblasts and osteoclasts.

    Science.gov (United States)

    Huang, Su; Eleniste, Pierre P; Wayakanon, Kornchanok; Mandela, Prashant; Eipper, Betty A; Mains, Richard E; Allen, Matthew R; Bruzzaniti, Angela

    2014-03-01

    Bone homeostasis is maintained by the balance between bone resorption by osteoclasts and bone formation by osteoblasts. Dysregulation in the activity of the bone cells can lead to osteoporosis, a disease characterized by low bone mass and an increase in bone fragility and risk of fracture. Kalirin is a novel GTP-exchange factor protein that has been shown to play a role in cytoskeletal remodeling and dendritic spine formation in neurons. We examined Kalirin expression in skeletal tissue and found that it was expressed in osteoclasts and osteoblasts. Furthermore, micro-CT analyses of the distal femur of global Kalirin knockout (Kal-KO) mice revealed significantly reduced trabecular and cortical bone parameters in Kal-KO mice, compared to WT mice, with significantly reduced bone mass in 8, 14 and 36week-old female Kal-KO mice. Male mice also exhibited a decrease in bone parameters but not to the level seen in female mice. Histomorphometric analyses also revealed decreased bone formation rate in 14week-old female Kal-KO mice, as well as decreased osteoblast number/bone surface and increased osteoclast surface/bone surface. Consistent with our in vivo findings, the bone resorbing activity and differentiation of Kal-KO osteoclasts was increased in vitro. Although alkaline phosphatase activity by Kal-KO osteoblasts was increased in vitro, Kal-KO osteoblasts showed decreased mineralizing activity, as well as decreased secretion of OPG, which was inversely correlated with ERK activity. Taken together, our findings suggest that deletion of Kalirin directly affects osteoclast and osteoblast activity, leading to decreased OPG secretion by osteoblasts which is likely to alter the RANKL/OPG ratio and promote osteoclastogenesis. Therefore, Kalirin may play a role in paracrine and/or endocrine signaling events that control skeletal bone remodeling and the maintenance of bone mass.

  10. FSH and TSH in the Regulation of Bone Mass: The Pituitary/Immune/Bone Axis

    Directory of Open Access Journals (Sweden)

    Graziana Colaianni

    2013-01-01

    Full Text Available Recent evidences have highlighted that the pituitary hormones have profound effects on bone, so that the pituitary-bone axis is now becoming an important issue in the skeletal biology. Here, we discuss the topical evidence about the dysfunction of the pituitary-bone axis that leads to osteoporotic bone loss. We will explore the context of FSH and TSH hormones arguing their direct or indirect role in bone loss. In addition, we will focus on the knowledge that both FSH and TSH have influence on proinflammatory and proosteoclastogenic cytokine expression, such as TNFα and IL-1, underlining the correlation of pituitary-bone axis to the immune system.

  11. Osteoporosis or Low Bone Mass at the Femur Neck or Lumbar Spine in Older Adults: United States, 2005-2008

    Science.gov (United States)

    ... Order from the National Technical Information Service NCHS Osteoporosis or Low Bone Mass at the Femur Neck ... Survey, 2005–2008. What is the prevalence of osteoporosis or low bone mass at the femur neck ...

  12. Fat mass is positively associated with bone mass in relatively thin adolescents: data from the Kitakata Kids Health Study.

    Science.gov (United States)

    Kouda, Katsuyasu; Fujita, Yuki; Sato, Yuho; Ohara, Kumiko; Nakamura, Harunobu; Uenishi, Kazuhiro; Iki, Masayuki

    2014-07-01

    Epidemiologic studies have found that higher body weight is associated with better bone health. Body weight consists of both fat mass (FM) and lean soft tissue mass (LSTM). Previous studies have examined the effects of FM levels during childhood on bone health, with conflicting results. In the present study, we investigated the independent contributions of FM to bone mass in Japanese adolescents. Subjects were 235 adolescents aged 15-18 years old in August 2010 and in August 2013 from the Kitakata Kids Health Study in Japan. We obtained cross-sectional data on body composition as well as bone mineral density (BMD). Body composition and BMD were measured using a dual-energy X-ray absorptiometry scanner. We found moderate and positive relationships between FM index and LSTM index (males, r=0.69; females, r=0.44). To verify a potentially additive effect of FM on the variance of bone variables beyond LSTM, we assessed the association between FM index and bone variables after stratification by tertiles of the LSTM index. In the lowest tertile of the LSTM index, FM index was significantly (PLSTM index. These findings indicate that FM can influence how high bone mass is obtained among relatively thin adolescents, but not among those who are of normal weight or overweight.

  13. The recent prevalence of Osteoporosis and low bone mass in the United States based on bone mineral density at the Femoral Neck or Lumbar Spine

    Science.gov (United States)

    The goal of our study was to estimate the prevalence of osteoporosis and low bone mass based on bone mineral density (BMD) at the femoral neck and the lumbar spine in adults 50 years and older in the United States (US). We applied prevalence estimates of osteoporosis or low bone mass at the femoral ...

  14. Effects of Low-Impact Dance on Blood Biochemistry, Bone Mineral Density, the Joint Range of Motion of Lower Extremities, Knee Extension Torque, and Fall in Females.

    Science.gov (United States)

    Wu, Hui Ying; Tu, Jui Hung; Hsu, Chin Hsing; Tsao, Te Hung

    2016-01-01

    The effect of low-impact dance on blood metabolites, the joint range of motion (ROM) of the lower extremities, knee extension torque, bone mass density (BMD), the number of falls, and the confidence to perform daily activities (Modified Falls Efficacy Scale [MFES]) was examined in older sedentary women (age: 59 ± 4 years) before and after a 16-week intervention. Results showed that the average score for the MFES, some parameters of blood chemistry, and joint ROM were significantly improved after low-impact intervention. In addition to improvements in blood lipids and body fat percentages, the increases shown in the parameters regarding the lower extremities may contribute to confidence in performing common daily activities in older women, although the number of falls did not significantly differ between the two groups during the 16-week period.

  15. Skeletal development of mice lacking bone sialoprotein (BSP--impairment of long bone growth and progressive establishment of high trabecular bone mass.

    Directory of Open Access Journals (Sweden)

    Wafa Bouleftour

    Full Text Available Adult Ibsp-knockout mice (BSP-/- display shorter stature, lower bone turnover and higher trabecular bone mass than wild type, the latter resulting from impaired bone resorption. Unexpectedly, BSP knockout also affects reproductive behavior, as female mice do not construct a proper "nest" for their offsprings. Multiple crossing experiments nonetheless indicated that the shorter stature and lower weight of BSP-/- mice, since birth and throughout life, as well as their shorter femur and tibia bones are independent of the genotype of the mothers, and thus reflect genetic inheritance. In BSP-/- newborns, µCT analysis revealed a delay in membranous primary ossification, with wider cranial sutures, as well as thinner femoral cortical bone and lower tissue mineral density, reflected in lower expression of bone formation markers. However, trabecular bone volume and osteoclast parameters of long bones do not differ between genotypes. Three weeks after birth, osteoclast number and surface drop in the mutants, concomitant with trabecular bone accumulation. The growth plates present a thinner hypertrophic zone in newborns with lower whole bone expression of IGF-1 and higher IHH in 6 days old BSP-/- mice. At 3 weeks the proliferating zone is thinner and the hypertrophic zone thicker in BSP-/- than in BSP+/+ mice of either sex, maybe reflecting a combination of lower chondrocyte proliferation and impaired cartilage resorption. Six days old BSP-/- mice display lower osteoblast marker expression but higher MEPE and higher osteopontin(Opn/Runx2 ratio. Serum Opn is higher in mutants at day 6 and in adults. Thus, lack of BSP alters long bone growth and membranous/cortical primary bone formation and mineralization. Endochondral development is however normal in mutant mice and the accumulation of trabecular bone observed in adults develops progressively in the weeks following birth. Compensatory high Opn may allow normal endochondral development in BSP-/- mice

  16. Skeletal development of mice lacking bone sialoprotein (BSP)--impairment of long bone growth and progressive establishment of high trabecular bone mass.

    Science.gov (United States)

    Bouleftour, Wafa; Boudiffa, Maya; Wade-Gueye, Ndeye Marième; Bouët, Guénaëlle; Cardelli, Marco; Laroche, Norbert; Vanden-Bossche, Arnaud; Thomas, Mireille; Bonnelye, Edith; Aubin, Jane E; Vico, Laurence; Lafage-Proust, Marie Hélène; Malaval, Luc

    2014-01-01

    Adult Ibsp-knockout mice (BSP-/-) display shorter stature, lower bone turnover and higher trabecular bone mass than wild type, the latter resulting from impaired bone resorption. Unexpectedly, BSP knockout also affects reproductive behavior, as female mice do not construct a proper "nest" for their offsprings. Multiple crossing experiments nonetheless indicated that the shorter stature and lower weight of BSP-/- mice, since birth and throughout life, as well as their shorter femur and tibia bones are independent of the genotype of the mothers, and thus reflect genetic inheritance. In BSP-/- newborns, µCT analysis revealed a delay in membranous primary ossification, with wider cranial sutures, as well as thinner femoral cortical bone and lower tissue mineral density, reflected in lower expression of bone formation markers. However, trabecular bone volume and osteoclast parameters of long bones do not differ between genotypes. Three weeks after birth, osteoclast number and surface drop in the mutants, concomitant with trabecular bone accumulation. The growth plates present a thinner hypertrophic zone in newborns with lower whole bone expression of IGF-1 and higher IHH in 6 days old BSP-/- mice. At 3 weeks the proliferating zone is thinner and the hypertrophic zone thicker in BSP-/- than in BSP+/+ mice of either sex, maybe reflecting a combination of lower chondrocyte proliferation and impaired cartilage resorption. Six days old BSP-/- mice display lower osteoblast marker expression but higher MEPE and higher osteopontin(Opn)/Runx2 ratio. Serum Opn is higher in mutants at day 6 and in adults. Thus, lack of BSP alters long bone growth and membranous/cortical primary bone formation and mineralization. Endochondral development is however normal in mutant mice and the accumulation of trabecular bone observed in adults develops progressively in the weeks following birth. Compensatory high Opn may allow normal endochondral development in BSP-/- mice, while impairing

  17. Disruption of BMP Signaling in Osteoblasts Through Type IA Receptor (BMPRIA) Increases Bone Mass*

    Science.gov (United States)

    Kamiya, Nobuhiro; Ye, Ling; Kobayashi, Tatsuya; Lucas, Donald J; Mochida, Yoshiyuki; Yamauchi, Mitsuo; Kronenberg, Henry M; Feng, Jian Q; Mishina, Yuji

    2008-01-01

    Bone morphogenetic proteins (BMPs) are known as ectopic bone inducers. The FDA approved BMPs (BMP2 and BMP7) for clinical use. However, direct effects of BMPs on endogenous bone metabolism are not yet well known. We conditionally disrupted BMP receptor type IA (BMPRIA) in osteoblasts during weanling and adult stages to show the impact of BMP signaling on endogenous bone modeling and remodeling. Cre recombination was detected in immature osteoblasts in the periosteum, osteoblasts, and osteocytes but not in chondrocytes and osteoclasts after tamoxifen administration. Bmpr1a conditional knockout mice (cKO) showed increased bone mass primarily in trabecular bone at P21 and 22 wk as determined by H&E staining. Vertebrae, tails, and ribs showed increased radiodensity at 22 wk, consistent with a significant increase in BMD. Both μCT and histomorphometry showed an increase in trabecular BV/TV and thickness of cKO adult bones, whereas osteoclast number, bone formation rate, and mineral apposition rate were decreased. Expression levels of bone formation markers (Runx2 and Bsp), resorption markers (Mmp9, Ctsk, and Tracp), and Rankl were decreased, and Opg was increased in adult bones, resulting in a reduction in the ratio of Rankl to osteoprotegerin (Opg). The reduction in osteoclastogenesis through the RANKL–OPG pathway was also observed in weanling stages and reproduced in newborn calvaria culture. These results suggest that Bmpr1a cKO increased endogenous bone mass primarily in trabecular bone with decreased osteoclastogenesis through the RANKL–OPG pathway. We conclude that BMPRIA signaling in osteoblasts affects both bone formation and resorption to reduce endogenous bone mass in vivo. PMID:18684091

  18. Disruption of BMP signaling in osteoblasts through type IA receptor (BMPRIA) increases bone mass.

    Science.gov (United States)

    Kamiya, Nobuhiro; Ye, Ling; Kobayashi, Tatsuya; Lucas, Donald J; Mochida, Yoshiyuki; Yamauchi, Mitsuo; Kronenberg, Henry M; Feng, Jian Q; Mishina, Yuji

    2008-12-01

    Bone morphogenetic proteins (BMPs) are known as ectopic bone inducers. The FDA approved BMPs (BMP2 and BMP7) for clinical use. However, direct effects of BMPs on endogenous bone metabolism are not yet well known. We conditionally disrupted BMP receptor type IA (BMPRIA) in osteoblasts during weanling and adult stages to show the impact of BMP signaling on endogenous bone modeling and remodeling. Cre recombination was detected in immature osteoblasts in the periosteum, osteoblasts, and osteocytes but not in chondrocytes and osteoclasts after tamoxifen administration. Bmpr1a conditional knockout mice (cKO) showed increased bone mass primarily in trabecular bone at P21 and 22 wk as determined by H&E staining. Vertebrae, tails, and ribs showed increased radiodensity at 22 wk, consistent with a significant increase in BMD. Both muCT and histomorphometry showed an increase in trabecular BV/TV and thickness of cKO adult bones, whereas osteoclast number, bone formation rate, and mineral apposition rate were decreased. Expression levels of bone formation markers (Runx2 and Bsp), resorption markers (Mmp9, Ctsk, and Tracp), and Rankl were decreased, and Opg was increased in adult bones, resulting in a reduction in the ratio of Rankl to osteoprotegerin (Opg). The reduction in osteoclastogenesis through the RANKL-OPG pathway was also observed in weanling stages and reproduced in newborn calvaria culture. These results suggest that Bmpr1a cKO increased endogenous bone mass primarily in trabecular bone with decreased osteoclastogenesis through the RANKL-OPG pathway. We conclude that BMPRIA signaling in osteoblasts affects both bone formation and resorption to reduce endogenous bone mass in vivo.

  19. Effects of denosumab, alendronate, or denosumab following alendronate on bone turnover, calcium homeostasis, bone mass and bone strength in ovariectomized cynomolgus monkeys.

    Science.gov (United States)

    Kostenuik, Paul J; Smith, Susan Y; Samadfam, Rana; Jolette, Jacquelin; Zhou, Lei; Ominsky, Michael S

    2015-04-01

    Postmenopausal osteoporosis is a chronic disease wherein increased bone remodeling reduces bone mass and bone strength. Antiresorptive agents including bisphosphonates are commonly used to mitigate bone loss and fracture risk. Osteoclast inhibition via denosumab (DMAb), a RANKL inhibitor, is a newer approach for reducing fracture risk in patients at increased risk for fracture. The safety of transitioning from bisphosphonate therapy (alendronate; ALN) to DMAb was examined in mature ovariectomized (OVX) cynomolgus monkeys (cynos). One day after OVX, cynos (7-10/group) were treated with vehicle (VEH, s.c.), ALN (50 μg/kg, i.v., twice monthly) or DMAb (25 mg/kg/month, s.c.) for 12 months. Other animals received VEH or ALN for 6 months and then transitioned to 6 months of DMAb. DMAb caused significantly greater reductions in serum CTx than ALN, and transition from ALN to DMAb caused further reductions relative to continued ALN. DMAb and ALN decreased serum calcium (Ca), and transition from ALN to DMAb resulted in a lesser decline in Ca relative to DMAb or to VEH-DMAb transition. Bone histomorphometry indicated significantly reduced trabecular and cortical remodeling with DMAb or ALN. Compared with ALN, DMAb caused greater reductions in osteoclast surface, eroded surface, cortical porosity and fluorochrome labeling, and transition from ALN to DMAb reduced these parameters relative to continued ALN. Bone mineral density increased in all active treatment groups relative to VEH controls. Destructive biomechanical testing revealed significantly greater vertebral strength in all three groups receiving DMAb, including those receiving DMAb after ALN, relative to VEH controls. Bone mass and strength remained highly correlated in all groups at all tested skeletal sites, consistent with normal bone quality. These data indicate that cynos transitioned from ALN to DMAb exhibited reduced bone resorption and cortical porosity, and increased BMD and bone strength, without

  20. Swimming and bone: Is low bone mass due to hypogravity alone or does other physical activity influence it?

    Science.gov (United States)

    Gómez-Bruton, A; González-Agüero, A; Gómez-Cabello, A; Matute-Llorente, A; Casajús, J A; Vicente-Rodríguez, G

    2016-05-01

    Swimming during adolescence has shown neutral or even negative effects on bone mass. Nevertheless, it is still unknown if these effects are due to swimming or to other factors, such as sedentary behaviors. Three objectives were described (1) to measure objective physical activity (PA) additional to swimming performed by adolescent swimmers (SWI) and compare it to that performed by normo-active controls (CG), (2) to describe the relationship between objectively measured PA and bone mass, and (3) to compare bone mass of swimmers that meet the World Health Organization PA guidelines (active) WHO and those that do not (inactive). A total of 71 SWI (33 females) and 41 CG (17 females) wore an accelerometer for at least 4 days. PA was expressed as the amount of time (minutes/day) in each intensity [sedentary/light/moderate or vigorous (VPA), and the sum of moderate and vigorous (MVPA)]. Using the cutoff points proposed by Vanhelst et al. SWI were classified as active or inactive according to whether they reached 60 min of weight-bearing MVPA per day or not. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry, and bone strength values were calculated with peripheral quantitative computed tomography. Differences in PA intensities were calculated between SWI and CG. The relation of VPA to bone mass was studied in the SWI. Male-SWI spend less time in VPA and MVPA than male-GC, which partly explains the lower BMD values in SWI than CG. Swimming may displace weight-bearing VPA with serious implications on bone health.

  1. Prognostic value of biochemical variables for survival after surgery for metastatic bone disease of the extremities.

    Science.gov (United States)

    Sørensen, Michala Skovlund; Hovgaard, Thea Bechman; Hindsø, Klaus; Petersen, Michael Mørk

    2017-03-01

    Prediction of survival in patients having surgery for metastatic bone disease in the extremities (MBDex) has been of interest in more than two decades. Hitherto no consensus on the value of biochemical variables has been achieved. Our purpose was (1) to investigate if standard biochemical variables have independent prognostic value for survival after surgery for MBDex and (2) to identify optimal prognostic cut off values for survival of biochemical variables. In a consecutive cohort of 270 patients having surgery for MBDex, we measured preoperative biochemical variables: hemoglobin, alkaline phosphatase, C-reactive protein and absolute, neutrophil and lymphocyte count. ROC curve analyses were performed to identify optimal cut off levels. Independent prognostic factors for variables were addressed with multiple Cox regression analyses. Optimal cut off levels were identified as: hemoglobin 7.45 mmol/L, absolute lymphocyte count 8.5 × 10(9) /L, neutrophil 5.68 × 10(9) /L, lymphocyte 1.37 × 10(9) /L, C-reactive protein 22.5 mg/L, and alkaline phosphatase 129 U/L. Regression analyses found alkaline phosphatase (HR 2.49) and neutrophil count (HR 2.49) to be independent prognostic factors. We found neutrophil count and alkaline phosphatase to be independent prognostic variables in predicting survival in patients after surgery for MBDex. © 2016 Wiley Periodicals, Inc.

  2. Sclerostin-antibody treatment of glucocorticoid-induced osteoporosis maintained bone mass and strength

    Science.gov (United States)

    Jiang, L.; Lay, E. Y.-A.; Zhong, Z.; Ritchie, R. O.; Li, X.; Ke, H.; Lane, N. E.

    2016-01-01

    Summary This study was to determine if antibody against sclerostin (Scl-Ab) could prevent glucocorticoid (GC)-induced osteoporosis in mice. We found that Scl-Ab prevented GC-induced reduction in bone mass and bone strength and that the anabolic effects of Scl-Ab might be partially achieved through the preservation of osteoblast activity through autophagy. Introduction Glucocorticoids (GCs) inhibit bone formation by altering osteoblast and osteocyte cell activity and lifespan. A monoclonal antibody against sclerostin, Scl-Ab, increased bone mass in both preclinical animal and clinical studies in subjects with low bone mass. The objectives of this study were to determine if treatment with the Scl-Ab could prevent loss of bone mass and strength in a mouse model of GC excess and to elucidate if Scl-Ab modulated bone cell activity through autophagy. Methods We generated reporter mice that globally expressed dsRed fused to LC3, a protein marker for autophagosomes, and evaluated the dose-dependent effects of GCs (0, 0.8, 2.8, and 4 mg/kg/day) and Scl-Ab on autophagic osteoblasts, bone mass, and bone strength. Results GC treatment at 2.8 and 4 mg/kg/day of methylprednisolone significantly lowered trabecular bone volume (Tb-BV/TV) at the lumbar vertebrae and distal femurs, cortical bone mass at the mid-shaft femur (FS), and cortical bone strength compared to placebo (PL). In mice treated with GC and Scl-Ab, Tb-BV/TV increased by 60–125 %, apparent bone strength of the lumbar vertebrae by 30–70 %, FS-BV by 10–18 %, and FS-apparent strength by 13–15 %, as compared to GC vehicle-treated mice. GC treatment at 4 mg/kg/ day reduced the number of autophagic osteoblasts by 70 % on the vertebral trabecular bone surface compared to the placebo group (PL, GC 0 mg), and GC + Scl-Ab treatment. Conclusions Treatment with Scl-Ab prevented GC-induced reduction in both trabecular and cortical bone mass and strength and appeared to maintain osteoblast activity through autophagy. PMID

  3. Daily leptin blunts marrow fat but does not impact bone mass in calorie-restricted mice.

    Science.gov (United States)

    Devlin, M J; Brooks, D J; Conlon, C; Vliet, M van; Louis, L; Rosen, C J; Bouxsein, M L

    2016-06-01

    Starvation induces low bone mass and high bone marrow adiposity in humans, but the underlying mechanisms are poorly understood. The adipokine leptin falls in starvation, suggesting that hypoleptinemia may be a link between negative energy balance, bone marrow fat accumulation, and impaired skeletal acquisition. In that case, treating mice with leptin during caloric restriction (CR) should reduce marrow adipose tissue (MAT) and improve bone mass. To test this hypothesis, female C57Bl/6J mice were fed a 30% CR or normal (N) diet from 5 to 10 weeks of age, with daily injections of vehicle (VEH), 1mg/kg leptin (LEP1), or 2mg/kg leptin (LEP2) (N=6-8/group). Outcomes included body mass, body fat percentage, and whole-body bone mineral density (BMD) via peripheral dual-energy X-ray absorptiometry, cortical and trabecular microarchitecture via microcomputed tomography (μCT), and MAT volume via μCT of osmium tetroxide-stained bones. Overall, CR mice had lower body mass, body fat percentage, BMD, and cortical bone area fraction, but more connected trabeculae, vs N mice (Pleptin treatment blunted MAT formation in CR mice by 50% vs VEH (Pleptin doses). CR LEP2 mice weighed less vs CR VEH mice at 9-10 weeks of age (Pleptin treatment did not affect body fat percentage, BMD, or bone microarchitecture within either diet. These data demonstrate that once daily leptin bolus during CR inhibits bone marrow adipose expansion without affecting bone mass acquisition, suggesting that leptin has distinct effects on starvation-induced bone marrow fat formation and skeletal acquisition. © 2016 Society for Endocrinology.

  4. Mechanisms by which nutritional disorders cause reduced bone mass in adults.

    Science.gov (United States)

    Miller, Karen K

    2003-03-01

    Nutritional disorders that cause bone loss in adults include disordered eating behaviors (female athlete triad and anorexia nervosa), gastrointestinal diseases (celiac sprue, inflammatory bowel disease, and other malabsorption syndromes), alcoholism, and hypervitaminosis A. These disorders exert their effects on bone through a number of mechanisms, including estrogen deficiency. Deficiencies of anabolic hormones may also be important, including insulin-like growth factor I (IGF-I), a nutritionally regulated bone trophic factor. In addition, low weight itself is a risk factor for bone loss and decreased bone formation. Reduced calcium and vitamin D availability, with resultant secondary hyperparathyroidism, is another important mechanism of bone loss in nutritional disorders. This review discusses nutritional causes of reduced bone mass in adults and how nutritional disorders exert deleterious effects on the skeleton.

  5. Dietary Habits, Nutrients and Bone Mass in Spanish Premenopausal Women: The Contribution of Fish to Better Bone Health

    Directory of Open Access Journals (Sweden)

    Julian F. Calderon-Garcia

    2012-12-01

    Full Text Available The moderate consumption of fish is recommended for a healthy diet and is also a feature of the Mediterranean diet. Fish is a major food group in diets throughout the world, and studies show that fish consumption is associated with a lower risk of a number of conditions. Spain has one of the highest annual per capita consumptions of fish worldwide. As fish is a source of high quality protein; n-3 polyunsaturated fatty acids; vitamins, such as A and D; and minerals, such as selenium, calcium, iodine, magnesium, copper and zinc, nutrients that have positive effects on bone characteristics, it has been proposed that its consumption could improve bone health. In this cross-sectional study, we have investigated the relationship between dietary habits and nutrient intake of 151 Spanish premenopausal women and analyzed the association of fish consumption on bone mass measured by quantitative ultrasound of the phalanges. A higher (P < 0.05 bone mass and vitamin D intake (P < 0.05 was observed in the group with a fish intake of 5–7 servings/week. We conclude that increased fish consumption is helpful in maintaining an adequate bone mass in Spanish premenopausal women.

  6. Dietary habits, nutrients and bone mass in Spanish premenopausal women: the contribution of fish to better bone health.

    Science.gov (United States)

    Calderon-Garcia, Julian F; Moran, Jose M; Roncero-Martin, Raul; Rey-Sanchez, Purificacion; Rodriguez-Velasco, Francisco J; Pedrera-Zamorano, Juan D

    2012-12-27

    The moderate consumption of fish is recommended for a healthy diet and is also a feature of the Mediterranean diet. Fish is a major food group in diets throughout the world, and studies show that fish consumption is associated with a lower risk of a number of conditions. Spain has one of the highest annual per capita consumptions of fish worldwide. As fish is a source of high quality protein; n-3 polyunsaturated fatty acids; vitamins, such as A and D; and minerals, such as selenium, calcium, iodine, magnesium, copper and zinc, nutrients that have positive effects on bone characteristics, it has been proposed that its consumption could improve bone health. In this cross-sectional study, we have investigated the relationship between dietary habits and nutrient intake of 151 Spanish premenopausal women and analyzed the association of fish consumption on bone mass measured by quantitative ultrasound of the phalanges. A higher (P < 0.05) bone mass and vitamin D intake (P < 0.05) was observed in the group with a fish intake of 5-7 servings/week. We conclude that increased fish consumption is helpful in maintaining an adequate bone mass in Spanish premenopausal women.

  7. Iron overload increases osteoclastogenesis and aggravates the effects of ovariectomy on bone mass.

    Science.gov (United States)

    Xiao, Wang; Beibei, Fei; Guangsi, Shen; Yu, Jiang; Wen, Zhang; Xi, Huang; Youjia, Xu

    2015-09-01

    Postmenopausal osteoporosis is a metabolic disease associated with estrogen deficiency. The results of numerous studies have revealed the positive correlation between iron accumulation and postmenopausal osteoporotic status. Although the results of previous studies have indicated that estrogen or iron alone have an effect on bone metabolism, their combined effects are not well defined. Using an in vivo mouse model, we found that bone mass was minimally affected by an excess of iron in the presence of estrogen. Once the source of estrogen was removed (ovariectomy), iron accumulation significantly decreased bone mass. These effects were accompanied by fluctuations in the level of oxidative stress. To determine whether these effects were related to bone formation or bone resorption, primary osteoblasts (OBs), RAW264.7 cells, and bone-marrow-derived macrophages were used for in vitro experiments. We found that iron accumulation did inhibit the activity of OBs. However, estrogen had little effect on this inhibition. In contrast, iron promoted osteoclast differentiation through the production of reactive oxygen species. Estrogen, a powerful reactive oxygen scavenger, suppressed this effect in osteoclasts. Our data provided direct evidence that iron affected the bone mass only in the absence of estrogen. The inhibitory effect of estrogen on iron-induced osteopenia was particularly relevant to bone resorption rather than bone formation. © 2015 Society for Endocrinology.

  8. Young Coconut Juice Supplementation Results in Greater Bone Mass and Bone Formation Indices in Ovariectomized Rats: A Preliminary Study.

    Science.gov (United States)

    Morii, Yuko; Matsushita, Hiroshi; Minami, Akira; Kanazawa, Hiroaki; Suzuki, Takashi; Subhadhirasakul, Sanan; Watanabe, Kazushi; Wakatsuki, Akihiko

    2015-12-01

    Young coconut juice (Cocos nucifera Linn.) (YCJ) has traditionally been consumed to alleviate symptoms associated with menopause by women in Southeast Asia. The aim of the present study was to determine the effects of YCJ on bone metabolism in ovariectomized rats. Female 10-week-old Wistar rats were randomly assigned to the following 4 groups: Baseline, Sham, Ovx, and Ovx + YCJ (n = 10 rats per group). Rats in the Baseline group were sacrificed immediately, and those in the other groups were subjected to either sham operation (Sham) or bilateral ovariectomy (Ovx and Ovx + YCJ). The Ovx + YCJ rats were administered 5×-concentrated YCJ at a dose of 10 mL/kg body weight per day. Six weeks after surgery, the rats were sacrificed, and indices of bone mass and bone histomorphometry were measured. The bone mineral density of the left femur was significantly higher in the Ovx + YCJ group compared with the Ovx group. In addition, the Ovx + YCJ group showed significantly higher measurements for bone formation rate compared with the Ovx group. These findings suggest that YCJ supplementation has a positive effect on bone metabolism and thus represents a possible intervention to slow the bone loss observed following menopause.

  9. Improvement of Lumbar Bone Mass after Infliximab Therapy in Crohn’s Disease Patients

    Directory of Open Access Journals (Sweden)

    Marina Mauro

    2007-01-01

    Full Text Available BACKGROUND: Patients with Crohn’s disease (CD have a high risk of developing osteoporosis, but the mechanisms underlying bone mass loss are unclear. Elevated proinflammatory cytokines, such as tumour necrosis factor-alpha (TNFα, have been implicated in the pathogenesis of bone resorption.

  10. A multicenter study of the influence of fat and lean mass on bone mineral content

    DEFF Research Database (Denmark)

    Hla, M M; Davis, J W; Ross, P D

    1996-01-01

    We examined the relative influence of fat and lean mass on bone mineral content (BMC) among 1600 early postmenopausal women aged 45-59 y from four geographical locations (Nottingham, United Kingdom; Portland, OR; Honolulu; and Copenhagen). Bone sites investigated included the major fracture sites...

  11. Maternal first-trimester diet and childhood bone mass: The Generation R Study

    NARCIS (Netherlands)

    D.H.M. Heppe (Denise); C. Medina-Gomez (Carolina); A. Hofman (Albert); O.H. Franco (Oscar); F. Rivadeneira Ramirez (Fernando); V.W.V. Jaddoe (Vincent)

    2013-01-01

    textabstractBackground: Maternal diet during pregnancy has been suggested to influence bone health in later life. Objective: We assessed the association of maternal first-trimester dietary intake during pregnancy with childhood bone mass. Design: In a prospective cohort study in 2819 mothers and the

  12. Revised proposal for the prevention of low bone mass in patients with classic galactosemia.

    NARCIS (Netherlands)

    van Erven, Britt; Römers, Myrna M M; Rubio-Gozalbo, M Estela

    2014-01-01

    Decreased bone mass is frequently encountered in classic galactosemia, an inborn error of galactose metabolism. This decrease is most prominent in adults, but is already seen in prepubertal children with increased risk of osteoporosis and fractures later in life. Therefore, bone health in patients w

  13. Clinical study evaluating bone mineral mass in the radius during skeletal growth. Single photon absorptiometry

    Energy Technology Data Exchange (ETDEWEB)

    Hagino, Hiroshi

    1989-01-01

    Using 125-I single photon absorptiometry, bone mineral measurements were performed on 206 healthy Japanese children (2 to 19 years of age). Bone mineral content (BMC), bone width (BW) and BMC/BW values were determined for the radius at distal 1/6 site (metaphysis) and distal 1/3 site (diaphysis). BMC/BW values at both sites correlated well with body height and weight. Bone mass in the diaphysis (distal 1/3 site) increased linearly during the 2-19 years of skeletal growth, but bone mass in the metaphysis (1/6 site) increased steeply during the pubertal period. In children receiving glucocorticoid therapy, bone mass was reduced in proportion to the duration of drug administration. In children under anticonvulsant therapy, the yearly increse in bone mass was significantly low especially in those patients with poor physical activity levels. Bone mineral decrease in the radius occurred in the children with hypopituitalism, hypothyroidism (cretinism), hyperthyroidism and Turner's syndrome.

  14. The importance and relevance of peak bone mass in the prevalence of osteoporosis.

    Science.gov (United States)

    Bonjour, Jean-Philippe; Chevalley, Thierry; Ferrari, Serge; Rizzoli, René

    2009-01-01

    Bone mass and strength achieved at the end of the growth period, simply designated as 'Peak Bone Mass (PBM)', plays an essential role in the risk of osteoporotic fractures occurring in adulthood. It is considered that an increase of PBM by one standard deviation would reduce the fracture risk by 50%. As estimated from twin studies, genetics is the major determinant of PBM, accounting for about 60 to 80% of its variance. During pubertal maturation, the size of the bone increases whereas the volumetric bone mineral density remains constant in both genders. At the end of puberty, the sex difference is essentially due to a greater bone size in male than female subjects. This is achieved by larger periosteal deposition in boys, thus conferring at PBM a better resistance to mechanical forces in men than in women. Sex hormones and the IGF-1 system are implicated in the bone sexual dimorphism occurring during pubertal maturation. The genetically determined trajectory of bone mass development can be modulated to a certain extent by modifiable environmental factors, particularly physical activity, calcium and protein intakes. Prepuberty appears to be an opportune time to modify environmental factors that impinge on bone mineral mass acquisition.

  15. Fat mass increase in 7-year-old children: more bone area but lower bone mineral density.

    Science.gov (United States)

    Hrafnkelsson, Hannes; Sigurdsson, Gunnar; Magnusson, Kristjan Th; Sigurdsson, Emil L; Johannsson, Erlingur

    2013-07-01

    The main aims of this study were, to evaluate what effect a change in fat mass (FM) and lean body mass (LBM) has on bone parameters over 2 years' time, in 7-year-old school children and to see what effect fitness had on bone parameters in these children. A repeated-measures design study was conducted where children born in 1999 from six elementary schools in Reykjavik, Iceland were measured twice. All children attending second grade in these six schools were invited to participate. Three hundred twenty-one children were invited, 211 underwent dual-energy X-ray absorptiometry (DXA) scans at the age of seven, and 164 (78 %) of the 211 had DXA scans again 2 years later. Increase in both FM and LBM was associated with increased total body bone mineral content (BMC) and bone area (BA). An increase in FM was more strongly positively associated with BA while an increase in LBM was more strongly associated with an increase in BMC. An increase in FM was negatively associated with change in bone mineral density (BMD), but an increase in LBM was positively associated with change in BMD. Fitness was positively associated with bone parameters when weight, height and sex were accounted for. The present results suggest that an increase in fat mass over 2 years is associated with an increase in BA and BMC, but a decrease in BMD in the whole body. An increase in LBM accrual, on the other hand, is positively associated with all bone parameters in the body. Fitness is associated with both BMC and BMD but not BA.

  16. The effect ofethnicity on appendicular bone m.ass in white, coloured ...

    African Journals Online (AJOL)

    weight coloured girls had significantly greater. BMC and ... putatively influence bone mass, namely height, weight, body fat ... ren over the age of 10 years by the Tanner method. 16,17 .... Skinfold thickness does not have a Gaussian distribu-.

  17. A 21-Week Bone Deposition Promoting Exercise Programme Increases Bone Mass in Young People with Down Syndrome

    Science.gov (United States)

    Gonzalez-Aguero, Alejandro; Vicente-Rodriguez, German; Gomez-Cabello, Alba; Ara, Ignacio; Moreno, Luis A.; Casajus, Jose A.

    2012-01-01

    Aim: To determine whether the bone mass of young people with Down syndrome may increase, following a 21-week conditioning training programme including plyometric jumps. Method: Twenty-eight participants with Down syndrome (13 females, 15 males) aged 10 to 19 years were divided into exercise (DS-E; n = 14; eight females, six males mean age 13y 8mo,…

  18. A 21-Week Bone Deposition Promoting Exercise Programme Increases Bone Mass in Young People with Down Syndrome

    Science.gov (United States)

    Gonzalez-Aguero, Alejandro; Vicente-Rodriguez, German; Gomez-Cabello, Alba; Ara, Ignacio; Moreno, Luis A.; Casajus, Jose A.

    2012-01-01

    Aim: To determine whether the bone mass of young people with Down syndrome may increase, following a 21-week conditioning training programme including plyometric jumps. Method: Twenty-eight participants with Down syndrome (13 females, 15 males) aged 10 to 19 years were divided into exercise (DS-E; n = 14; eight females, six males mean age 13y 8mo,…

  19. Obesity induced by high dietary fat leads to increased bone resorption marker, TRAP, and decreased bone mass in mice

    Science.gov (United States)

    Obesity, which is growing in prevalence, is a risk factor for such chronic health disorders as diabetes and cardiovascular diseases. However, it is thought to be a protective factor for osteoporosis and bone fractures in humans. Accumulating data in humans suggest that fat mass has a negative effect...

  20. Soft Tissue Masses in the Extremities: The Accuracy of an Ultrasonographic Diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    An, Ji Young; Park, So Young; Park, Ji Seon; Jin, Wook; Ryu, Kyung Nam [Kyung Hee University Medical Center, Seoul (Korea, Republic of)

    2011-09-15

    We wanted to retrospectively determine the accuracy of an ultrasonographic diagnosis of superficial soft tissue masses in the extremities by using the histologic results as the reference standard. From January 2005 to June 2010, 154 patients with soft tissue masses in the extremities and who underwent ultrasonographic evaluation followed by biopsy or resection were retrospectively evaluated. The ultrasonographic and histologic diagnoses of the soft tissue masses were lipoma, ganglion cyst, hemangioma, neurogenic tumor, giant cell tumor of the tendon sheath, epidermoid cyst, fibroma, glomus tumor, Baker's cyst and neurofibromatosis. Out of 154 patients, 114 (74%) patients showed concordance between the histologic diagnosis and the ultrasonographic diagnosis, and the remaining 40 (26%) patients did not. The diagnostic accuracy of each soft tissue mass was 95% for lipoma, 83% for ganglion cyst, 75% for hemangioma, 72% for neurogenic tumor, 50% for giant cell tumor of the tendon sheath, 43% for epidermoid cyst, 33% for fibroma and 100% each for glomus tumor, fibromatosis and Baker's cyst. Aside from these tumors, there were also sarcoma, malignant melanoma, elastofibroma, Kimura disease and pilomatricoma. Among the cases that showed discordance between the histologic diagnosis and the ultrasonographic diagnosis, three of them were notable; pilomatricoma being misdiagnosed as dermatofibroma protuberans, angiolipoma being misdiagnosed as vascular leiomyoma and malignant fibrous histiocytoma being misdiagnosed as a malignant soft tissue mass. The accuracy of an ultrasonographic diagnosis for soft tissue masses in the extremities varies greatly according to each type of mass. Lipoma, ganglion cyst, hemangioma, glomus tumor, neurogenic tumor and Baker's cyst showed a relatively high rate of concordance between the ultrasonographic diagnosis and the histologic diagnosis, but epidermoid cyst and fibroma showed a relatively lower rate of concordance

  1. Maintaining Restored Bone with Bisphoshonate in the Ovariectomized Rat Skeleton: Dynamic Histomorphometry of Changes in Bone Mass

    Science.gov (United States)

    Jee, W. S. S.; Tang, L.; Ke, H. Z.; Setterberg, R. B.; Kimmel, D. B.

    1993-01-01

    This experiment contains the crucial data for the Lose, Restore and Maintain (LRM) concept, a practical approach for reversing existing osteoporosis. The LRM concept uses ovariectomy (ox) to lose bone, an anabolic agent to restore bone mass and then switches to an anti-resorptive agent to maintain bone mass. We ox'd or sham-ox'd rats for 150 days (Loss Phase), treated them with 6 mg PGE2/kg/d for 75 days to restore lost cancellous bone mass (Restore Phase) and then stopped PGE2 treatment and began treatment with 1 or 5 micro-g/kg Risedronate, a bisphosphonate twice a week for 60 days (Maintain Phase). During the Loss Phase, cancellous bone volumes of the proximal tibial metaphysis (PTM) in the ox'd rat fell to 19% of initial controls. During the Restore Phase, the PTM bone volume in ox'd rats doubled. However, when PGE2 treatment was stopped, the PGE2-induced cancellous bone disappeared. In contrast, 5 micro-g of Risedronate inhibited the bone loss and maintained it at the PGE2 treatment level. The key dynamic histomorphometry value for the restore (R) and maintenance (M) phases was the ratio of bone formation to resorption rates. The ratio was elevated to 5.8 in the R phase and depressed to 0.4 for no and 1 micro-g Risedronate treated M phase and to a ratio of near unity of 1.1 for the 5 micro-g Risedronate treatment. These findings indicate that we were successful in maintaining the new PTM bone induced by PGE2 after discontinuing PGE2 by administering enough Risedronate, a resorption inhibitor. We concluded that the LRM concept is correct and such an approach should be considered when employing anabolic agents or growth factors in the treatment of osteoporosis. Continued use of an anabolic agent may not be appropriate because of cost, potential adverse side effects and a loss of efficacy.

  2. Maintaining Restored Bone with Bisphosphonate in the Ovariectomized Rat Skeleton: Dynamic Histomorphometry of Changes in Bone Mass

    Science.gov (United States)

    Jee, W. S. S.; Tang, L.; Ke, H. Z.; Setterberg, R. B.; Kimmel, D. B.

    1993-01-01

    This experiment contains the crucial data for the Lose, Restore and Maintain (LRM) concept, a practical approach for reversing existing osteoporosis. The LRM concept uses ovariectomy (ox) to lose bone, an anabolic agent to restore bone mass and then switches to an antiresorptive agent to maintain bone mass. We ox'd or sham-ox'd rats for 150 days (Loss Phase), treated them with 6 mg PGE(sub 2)kg/d for 75 days to restore lost cancellous bone mass (Restore Phase) and then stopped PGE(sub 2) treatment and began treatment with 1 or 5 micrograms/kg Risedronate, a bisphosphonate twice a week for 60 days (Maintain Phase). During the Loss Phase, cancellous bone volumes of the Proximal Tibial Metaphysis (PTM) in the ox'd rat fell to 19% of initial controls. During the Restore Phase, the PTM bone volume in ox'd rats doubled. However, when PGE(sub 2) treatment was stopped, the PGE(sub 2)-induced cancellous bone disappeared. In contrast, 5 miligrams of Risedronate inhibited the bone loss and maintained it at the PGE(sub 2) treatment level. The key dynamic histomorphometry value for the Restore (R) and Maintenance (M) phases was the ratio of bone formation to resorption rates. The ratio was elevated to 5.8 in the R phase and depressed to 0.4 for no and 1 miligram Risedronate treated M phase and to a ratio of near unity of 1.1 for the 5miligrams Risedronate treatment. These findings indicate that we were successful in maintaining the new PTM bone induced by PGE(sub 2) after discontinuing PGE(sub 2) by administering enough Risedronate, a resorption inhibitor. We concluded that the LRM concept is correct and such an approach should be considered when employing anabolic agents or growth factors in the treatment of osteoporosis. Continued use of an anabolic agent may not be appropriate because of cost, potential adverse side effects and a loss of efficacy.

  3. Cytoplasmic reactive oxygen species and SOD1 regulate bone mass during mechanical unloading.

    Science.gov (United States)

    Morikawa, Daichi; Nojiri, Hidetoshi; Saita, Yoshitomo; Kobayashi, Keiji; Watanabe, Kenji; Ozawa, Yusuke; Koike, Masato; Asou, Yoshinori; Takaku, Tomoiku; Kaneko, Kazuo; Shimizu, Takahiko

    2013-11-01

    Oxidative stress contributes to the pathogenesis of age-related diseases as well as bone fragility. Our previous study demonstrated that copper/zinc superoxide dismutase (Sod1)-deficient mice exhibit the induction of intracellular reactive oxygen species (ROS) and bone fragility resulting from low-turnover bone loss and impaired collagen cross-linking (Nojiri et al. J Bone Miner Res. 2011;26:2682-94). Mechanical stress also plays an important role in the maintenance of homeostasis in bone tissue. However, the molecular links between oxidative and mechanical stresses in bone tissue have not been fully elucidated. We herein report that mechanical unloading significantly increased intracellular ROS production and the specific upregulation of Sod1 in bone tissue in a tail-suspension experiment. We also reveal that Sod1 loss exacerbated bone loss via reduced osteoblastic abilities during mechanical unloading. Interestingly, we found that the administration of an antioxidant, vitamin C, significantly attenuated bone loss during unloading. These results indicate that mechanical unloading, in part, regulates bone mass via intracellular ROS generation and the Sod1 expression, suggesting that activating Sod1 may be a preventive strategy for ameliorating mechanical unloading-induced bone loss.

  4. Characterization of Low Bone Mass in Young Patients with Thalassemia by DXA, pQCT and Markers of Bone Turnover

    Science.gov (United States)

    Fung, Ellen B.; Vichinsky, Elliott P.; Kwiatkowski, Janet L.; Huang, James; Bachrach, Laura K.; Sawyer, Aenor J.; Zemel, Babette S.

    2011-01-01

    Previous reports using dual x-ray absorptiometry (DXA) suggest that up to 70% of adults with thalassemia major (Thal) have low bone mass. However, few studies have controlled for body size and pubertal delay, variables known to affect bone mass in this population. In this study, bone mineral content and areal density (BMC, aBMD) of the spine and whole body were assessed by DXA, and volumetric BMD and cortical geometries of the distal tibia by peripheral quantitative computed tomography (pQCT) in subjects with Thal (n=25, 11 male, 10 to 30 yrs) and local controls (n=34, 15 male, 7 to 30 yrs). Z-scores for bone outcomes were calculated from reference data from a large sample of healthy children and young adults. Fasting blood and urine were collected, pubertal status determined by self-assessment and dietary intake and physical activity assessed by written questionnaires. Subjects with Thal were similar in age, but had lower height, weight and lean mass index Z-scores (all p18 yrs, n=11) had lower tibial trabecular vBMD (p=0.03), cortical area, cortical BMC, cortical thickness, periosteal circumference and section modulus Z-scores (all p<0.01) compared to controls. Cortical area, cortical BMC, cortical thickness, and periosteal circumference Z-scores (p=0.02) were significantly lower in young Thal (≤18 yrs, n=14) compared to controls. In separate multivariate models, tibial cortical area, BMC, and thickness and spine aBMD and whole body BMC Z-scores remained lower in Thal compared to controls after adjustment for gender, lean mass and/or growth deficits (all p<0.01). Tanner stage was not predictive in these models. Osteocalcin, a marker of bone formation, was significantly reduced in Thal compared to controls after adjusting for age, puberty and whole body BMC (p=0.029). In summary, we have found evidence of skeletal deficits that cannot be dismissed as an artifact of small bone size or delayed maturity alone. Given that reduced bone density and strength are

  5. Menstrual irregularity and bone mass in premenopausal women: Cross-sectional associations with testosterone and SHBG

    Directory of Open Access Journals (Sweden)

    Otahal Petr

    2010-12-01

    Full Text Available Abstract Background There have been few studies examining the associations between menstrual irregularity, androgens and bone mass in population-based samples of premenopausal women. This study aimed to describe the associations between menstrual pattern, testosterone, sex hormone binding globulin (SHBG and bone mass in a population-based sample of premenopausal women. Methods Cross-sectional study (N = 382, mean age 31.5 years. Menstrual pattern was assessed by questionnaire, bone mass measured by quantitative ultrasound (QUS and androgen status was assessed by levels of serum testosterone, SHBG and the free androgen index (FAI. Results Women with irregular cycles (n = 41, 11% had higher free androgen index (FAI, P = 0.01 and higher QUS measurements including speed of sound (SOS, 1%, P Conclusion Irregular menstrual cycles were associated with higher bone mass in this population-based sample of premenopausal women suggesting menstrual disturbance should continue to be evaluated but may be less harmful for bone mass. The association between menstrual irregularity and bone mass was partially mediated by markers of androgen status especially free testosterone.

  6. Growth hormone mitigates loss of periosteal bone formation and muscle mass in disuse osteopenic rats

    DEFF Research Database (Denmark)

    Grubbe, M-C; Thomsen, Jesper Skovhus; Nyengaard, J R

    2014-01-01

    Growth hormone (GH) is a potent anabolic agent capable of increasing both bone and muscle mass. The aim was to investigate whether GH could counteract disuse-induced loss of bone and muscle mass in a rat model. Paralysis was induced by injecting 4 IU Botox (BTX) into the muscles of the right hind......BMD, -13%, Pmuscle mass (-69%, Pmuscle cell cross sectional area (CSA) (-73%, P... of periosteal BFR/BS (2-fold increase vs. BTX, Pmuscle mass (+29% vs. BTX, Pmuscle CSA (+11%, P=0.064). In conclusion, GH mitigates disuse...

  7. Outcome of oscillating saw open osteotomy in two-stage lower extremity bone transport with monolateral frame.

    Science.gov (United States)

    Corona, Pablo S; Ramirez-Nuñez, Luis J; Amat, Carles; Carrera, Luis

    2017-07-25

    Bone transport techniques have been widely used to solve massive bone defects due to trauma, osteomyelitis or bone tumors. The technique of bone interruption to achieve better new bone formation is a subject of debate. Low-energy osteotomy (LEO) techniques have been proposed as the gold standard. Some authors reject open osteotomy with an oscillating saw (OOS osteotomy), based on the danger of bone tissue thermal necrosis and periosteal damage. To date, however, there is no strong clinical evidence to discourage this high-energy (HEO) bone interruption technique. The aim of this study was to determine outcomes in using OOS osteotomy in a series of patients, where monolateral-frame bone transport has been used to resolve segmental bone defects of the lower extremity. The minimum accepted follow-up was 1 year. The primary endpoints were radiographic evidence of regenerated bone quality (Li classification) and final outcome (Cattaneo clinical system assessment). Further, we analyzed associated complications, and compared results with other published series. We hypothesized that OOS osteotomy produces results no less favorable than those achieved with other, low-energy techniques. A total of 54 patients, with an average bone defect of 8.58cm (CI95% 7.01-10.16), were enrolled in the study. In terms of regeneration quality, 84% of the regenerated segment shapes were associated with good outcomes; only 16% exhibited a shape (hypotrophic) predictive of a poor outcome. Regarding functional assessment, following the Cattaneo system, we found a total of 90% good or excellent results. Finally, the Bone Healing Index (BHI) in our series averaged 21.09 days per cm. The main complication observed was pin-track infection, occurring in 45% of the cases. According our data, the superiority of an LEO technique over HEO techniques is yet to be confirmed; it appears that any open osteotomy is effective, performed well and in a proper clinical setting, and that many factors other than

  8. Intercomparison of techniques for the non-invasive measurement of bone mass

    Energy Technology Data Exchange (ETDEWEB)

    Cohn, S.H.

    1981-01-01

    A variety of methods are presently available for the non-invasive measurement of bone mass of both normal individuals and patients with metabolic disorders. Chief among these methods are radiographic techniques such as radiogrammetry, photon absorptiometry, computer tomography, Compton scattering and neutron activation analysis. In this review, the salient features of the bone measurement techniques are discussed along with their accuracy and precision. The advantages and disadvantages of the various techniques for measuring bone mass are summarized. Where possible, intercomparisons are made of the various techniques.

  9. Effect of combined teriparatide and monthly minodronic acid therapy on cancellous bone mass in ovariectomized rats: a bone histomorphometry study.

    Science.gov (United States)

    Iwamoto, Jun; Seki, Azusa; Sato, Yoshihiro

    2014-07-01

    The purpose of the present study was to determine whether teriparatide and monthly minodronic acid would have an additive effect on cancellous bone mass in ovariectomized rats. Seven-week-old female Sprague-Dawley rats were randomized into five groups of 10 animals each, including a sham-operation+vehicle group, an ovariectomy (OVX)+vehicle group, an OVX+minodronic acid (6 μg/kgs.c., every 4 weeks) group, an OVX+teriparatide (20 μg/kgs.c., daily) group, and an OVX+minodronic acid+teriparatide group. After the 12-week experimental period, static and dynamic histomorphometric analyses were performed on the cancellous bone of the tibial proximal metaphysis. OVX decreased the bone volume per total volume (BV/TV) and the trabecular number (Tb.N) and increased the trabecular separation (Tb.Sp) as a result of increased bone remodeling. Minodronic acid prevented the OVX-induced decreases in BV/TV, while teriparatide increased the BV/TV and trabecular width (Tb.Wi) beyond the values of the sham controls. Minodronic acid prevented, but teriparatide only mitigated, the OVX-induced decrease in Tb.N, although both drugs similarly prevented the OVX-induced increase in Tb.Sp. A combination of teriparatide and minodronic acid further increased the BV/TV and Tb.N and decreased the Tb.Sp as a result of the suppression of bone remodeling, compared with teriparatide alone. These results suggest the differential effect of teriparatide and monthly minodronic acid on cancellous bone structure and the additive effect of the two drugs on cancellous bone mass in OVX rats. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Observing extreme-mass-ratio inspirals with eLISA/NGO

    CERN Document Server

    Gair, Jonathan R

    2012-01-01

    The extreme-mass-ratio inspirals (EMRIs) of stellar mass compact objects into massive black holes in the centres of galaxies are an important source of low-frequency gravitational waves for space-based detectors. We discuss the prospects for detecting these sources with the evolved Laser Interferometer Space Antenna (eLISA), recently proposed as an ESA mission candidate under the name NGO. We show that NGO could observe a few tens of EMRIs over its two year mission lifetime at redshifts z < 0.5 and describe how the event rate changes under possible alternative specifications of the eLISA design.

  11. Confirmation of Small Dynamical and Stellar Masses for Extreme Emission Line Galaxies at z~2

    CERN Document Server

    Maseda, Michael V; da Cunha, Elisabete; Rix, Hans-Walter; Pacifici, Camilla; Momcheva, Ivelina; Brammer, Gabriel B; Franx, Marijn; van Dokkum, Pieter; Bell, Eric F; Fumagalli, Mattia; Grogin, Norman A; Kocevski, Dale D; Koekemoer, Anton M; Lundgren, Britt F; Marchesini, Danilo; Nelson, Erica J; Patel, Shannon G; Skelton, Rosalind E; Straughn, Amber N; Trump, Jonathan R; Weiner, Benjamin J; Whitaker, Katherine E; Wuyts, Stijn

    2013-01-01

    Spectroscopic observations from the Large Binocular Telescope and the Very Large Telescope reveal kinematically narrow lines (~50 km/s) for a sample of 14 Extreme Emission Line Galaxies (EELGs) at redshifts 1.4 1. The stellar mass formed in this vigorous starburst phase represents a large fraction of the total (dynamical) mass, without a significantly massive underlying population of older stars. The occurrence of such intense events in shallow potentials strongly suggests that supernova-driven winds must be of critical importance in the subsequent evolution of these systems.

  12. The Survey of HI in Extremely Low-mass Dwarfs (SHIELD)

    CERN Document Server

    Cannon, John M; Haynes, Martha P; Janowiecki, Steven; Parker, Angela; Salzer, John J; Adams, Elizabeth A K; Engstrom, Eric; Huang, Shan; McQuinn, Kristen B W; Ott, Juergen; Saintonge, Amelie; Skillman, Evan D; Allan, John; Erny, Grace; Fliss, Palmer; Smith, AnnaLeigh

    2011-01-01

    We present first results from the "Survey of HI in Extremely Low-mass Dwarfs" (SHIELD), a multi-configuration EVLA study of the neutral gas contents and dynamics of galaxies with HI masses in the 10^6-10^7 Solar mass range detected by the Arecibo Legacy Fast ALFA (ALFALFA) survey. We describe the survey motivation and concept demonstration using VLA imaging of 6 low-mass galaxies detected in early ALFALFA data products. We then describe the primary scientific goals of SHIELD and present preliminary EVLA and WIYN 3.5m imaging of the 12 SHIELD galaxies. With only a few exceptions, the neutral gas distributions of these extremely low-mass galaxies are centrally concentrated. In only 1 system have we detected HI column densities higher than 10^21 cm^-2. Despite this, the stellar populations of all of these systems are dominated by blue stars. Further, we find ongoing star formation as traced by H alpha emission in 10 of the 11 galaxies with H alpha imaging obtained to date. Taken together these results suggest th...

  13. Subtropical air masses over eastern Canada: Their links to extreme precipitation

    Science.gov (United States)

    Gyakum, John; Wood, Alice; Milrad, Shawn; Atallah, Eyad

    2017-04-01

    We investigate extremely warm, moist air masses with an analysis of 850-hPa equivalent potential temperature (θe) extremes at Montreal, Quebec. The utility of using this metric is that it represents the thermodynamic property of air that ascends during a precipitation event. We produce an analysis of the 40 most extreme cases of positive θe, 10 for each season, based upon standardized anomalies from the 33-year climatology. The analysis shows the cases to be characterized by air masses with distinct subtropical traits for all seasons: reduced static stability, anomalously high precipitable water, and anomalously elevated dynamic tropopause heights. Persistent, slow moving upper- and lower-level features were essential in the build up of high- θe air encompassing much of eastern Canada. The trajectory analysis also showed anticyclonic curvature to all paths in all seasons, implying that the subtropical anticyclone is crucial in the transport of high- θe air. These atmospheric rivers during the winter are characterized by trajectories from the subtropical North Atlantic, and over the Gulf Stream current, northward into Montreal. In contrast, the summer anticyclonic trajectories are primarily continental, traveling from Texas north-northeastward into the Great Lakes, and then eastward into Montreal. The role of the air mass in modulating the strength of a precipitation event is addressed with an analysis of the expression, P = RD, where P is the total precipitation, and R is the precipitation rate, averaged through the duration, D, of the event. Though appearing simple, this expression includes R, (assumed to be same as condensation, with an efficiency of 1), which may be expressed as the product of vertical motion and the change of saturation mixing ratio following a moist adiabat, through the troposphere. This expression for R includes the essential ingredients of lift, air mass temperature, and static stability (implicit in vertical motion). We use this

  14. Observations of an extreme storm in interplanetary space caused by successive coronal mass ejections

    CERN Document Server

    Liu, Ying D; Kajdič, Primož; Kilpua, Emilia K J; Lugaz, Noé; Nitta, Nariaki V; Möstl, Christian; Lavraud, Benoit; Bale, Stuart D; Farrugia, Charles J; Galvin, Antoinette B

    2014-01-01

    Space weather refers to dynamic conditions on the Sun and in the space environment of the Earth, which are often driven by solar eruptions and their subsequent interplanetary disturbances. It has been unclear how an extreme space weather storm forms and how severe it can be. Here we report and investigate an extreme event with multi-point remote-sensing and in-situ observations. The formation of the extreme storm showed striking novel features. We suggest that the in-transit interaction between two closely launched coronal mass ejections resulted in the extreme enhancement of the ejecta magnetic field observed near 1 AU at STEREO A. The fast transit to STEREO A (in only 18.6 hours), or the unusually weak deceleration of the event, was caused by the preconditioning of the upstream solar wind by an earlier solar eruption. These results provide a new view crucial to solar physics and space weather as to how an extreme space weather event can arise from a combination of solar eruptions.

  15. S-process in low-mass extremely metal-poor stars

    CERN Document Server

    Cruz, Monique A; Weiss, Achim

    2013-01-01

    Extremely metal-poor low-mass stars experience an ingestion of protons into the helium-rich layer during the core He-flash, resulting in the production of neutrons through the reactions ^{12}C(p,\\gamma)^{13}N(\\beta)^{13}C(\\alpha,n)^{16}O. This is a potential site for the production of s-process elements in extremely metal-poor stars not occurring in more metal-rich counterparts. Observationally, the signatures of s-process elements in the two most iron deficient stars observed to date, HE1327-2326 & HE0107-5240, still await for an explanation. We investigate the possibility that low-mass EMP stars could be the source of s-process elements observed in extremely iron deficient stars, either as a result of self-enrichment or in a binary scenario as the consequence of a mass transfer episode. We present evolutionary and post-processing s-process calculations of a 1Msun stellar model with metallicities Z=0, 10^{-8} and 10^{-7}. We assess the sensitivity of nucleosynthesis results to uncertainties in the input ...

  16. Regulation of bone mass and osteoclast function depend on the F-actin modulator SWAP-70.

    Science.gov (United States)

    Garbe, Annette I; Roscher, Anne; Schüler, Christiane; Lutter, Anne-Helen; Glösmann, Martin; Bernhardt, Ricardo; Chopin, Michael; Hempel, Ute; Hofbauer, Lorenz C; Rammelt, Stefan; Egerbacher, Monika; Erben, Reinhold G; Jessberger, Rolf

    2012-10-01

    Bone remodeling involves tightly regulated bone-resorbing osteoclasts and bone-forming osteoblasts. Determining osteoclast function is central to understanding bone diseases such as osteoporosis and osteopetrosis. Here, we report a novel function of the F-actin binding and regulatory protein SWAP-70 in osteoclast biology. F-actin ring formation, cell morphology, and bone resorption are impaired in Swap-70(-/-) osteoclasts, whereas the expression of osteoclast differentiation markers induced in vitro by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL) remains unaffected. Swap-70(-/-) mice develop osteopetrosis with increased bone mass, abnormally dense bone, and impaired osteoclast function. Ectopic expression of SWAP-70 in Swap-70(-/-) osteoclasts in vitro rescues their deficiencies in bone resorption and F-actin ring formation. Rescue requires a functional pleckstrin homology (PH) domain, known to support membrane localization of SWAP-70, and the F-actin binding domain. Transplantation of SWAP-70-proficient bone marrow into Swap-70(-/-) mice restores osteoclast resorption capacity in vivo. The identification of the role of SWAP-70 in promoting osteoclast function through modulating membrane-proximal F-actin rearrangements reveals a new pathway to control osteoclasts and bone homeostasis.

  17. High bone turnover is associated with low bone mass and spinal fracture in postmenopausal women

    DEFF Research Database (Denmark)

    Ravn, Pernille; Rix, M; Andreassen, H;

    1997-01-01

    -eight women had a lumbar spine bone mineral density (BMD) above 0.860 g/cm2, and 278 women had a BMD below 0.860 g/cm2. Spinal fracture was diagnosed from lateral spine X-ray studies and defined as at least 20% height reduction (wedge, compression, or endplate fracture) in at least one vertebra (T4-L4). Bone......, and prevalence of spinal fracture, which supports the theory that high bone turnover is a risk factor for spinal fracture and osteoporosis....

  18. Effect of fat mass and lean mass on bone mineral density in postmenopausal and perimenopausal Thai women

    Directory of Open Access Journals (Sweden)

    Namwongprom S

    2013-02-01

    Full Text Available Sirianong Namwongprom,1 Sattaya Rojanasthien,2 Ampica Mangklabruks,3 Supasil Soontrapa,4 Chanpen Wongboontan,5 Boonsong Ongphiphadhanakul61Clinical Epidemiology Program and Department of Radiology, 2Department of Orthopaedics, 3Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 4Department of Orthopaedics, Faculty of Medicine, Khon Kaen University, Khon Kaen, 5Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 6Department of Internal Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, ThailandBackground: The purpose of this study was to investigate the association between fat mass, lean mass, and bone mineral density (BMD in postmenopausal and perimenopausal Thai women.Methods: A cross-sectional study was conducted in 1579 healthy Thai women aged 40–90 years. Total body, lumbar spine, total femur, and femoral neck BMD and body composition were measured by dual x-ray absorptiometry. To evaluate the associations between fat mass and lean mass and various measures of BMD, multivariable linear regression models were used to estimate the regression coefficients for fat mass and lean mass, first in separate equations and then with both fat mass and lean mass in the same equation.Results: Among the study population, 1448 subjects (91.7% were postmenopausal and 131 (8.3% were perimenopausal. In postmenopausal women, after controlling for age, height, and duration of menopause, both fat mass and lean mass were positively correlated with BMD when they were analyzed independently of each other. When included in the same equation, both fat mass and lean mass continued to show a positive effect, but lean mass had a significantly greater impact on BMD than fat mass at all regions except for total body. Lean mass but not fat mass had a positive effect on BMD at all skeletal sites except the lumbar spine, after controlling for age and height in perimenopausal

  19. Dairy food intake, peripheral bone structure, and muscle mass in elderly ambulatory women.

    Science.gov (United States)

    Radavelli-Bagatini, Simone; Zhu, Kun; Lewis, Joshua R; Prince, Richard L

    2014-07-01

    Previous studies suggest that dairy intake may be associated with reduced bone and muscle loss with aging, but there are limited data in the very old. We evaluated the association between intake of dairy foods and peripheral bone structure and muscle mass in 564 elderly women aged 80 to 92 (mean 84.7) years, who were participants of the Calcium Intake Fracture Outcome Study/CAIFOS Aged Extension Study (CAIFOS/CARES) cohort and attended the 10-year follow-up. Assessments included dairy consumption (milk, yogurt, and cheese) by a validated food frequency questionnaire, 15% tibia bone mass, area and volumetric bone mineral density (vBMD) by peripheral quantitative computed tomography (pQCT), and appendicular bone and skeletal muscle mass by dual-energy X-ray absorptiometry (DXA). Women were categorized according to tertiles of dairy intake: first tertile (≤ 1.5 servings/d), second tertile (1.5 to 2.2 servings/d) and third tertile (≥ 2.2 servings/d). Controlling for confounding factors, pQCT assessment at the 15% tibia showed that compared with those in the first tertile of dairy intake, women in the third tertile had 5.7% greater total bone mass (p = 0.005), principally because of an increase in cortical and subcortical bone mass (5.9%, p = 0.050), resulting in a 6.2% increase in total vBMD (p = 0.013). Trabecular but not cortical and subcortical vBMD was also higher (7.8%, p = 0.044). DXA assessment showed that women in the third tertile of dairy intake had greater appendicular bone mass (7.1%, p = 0.007) and skeletal muscle mass (3.3%, p = 0.014) compared with tertile 1. The associations with bone measures were dependent on dairy protein and calcium intakes, whereas the association with appendicular muscle mass was not totally dependent on dairy protein intake. Our results suggest a positive association of dairy intake with appendicular bone mineralization and muscle mass in elderly women. Because many fractures in this age group are of the appendicular skeleton

  20. The Impact of Different Amounts of Calcium Intake on Bone Mass and Arterial Calcification in Ovariectomized Rats.

    Science.gov (United States)

    Agata, Umon; Park, Jong-Hoon; Hattori, Satoshi; Aikawa, Yuki; Kakutani, Yuya; Ezawa, Ikuko; Akimoto, Takayuki; Omi, Naomi

    2015-01-01

    Reduced estrogen secretion and low calcium (Ca) intake are risk factors for bone loss and arterial calcification in female rodents. To evaluate the effects of Ca intake at different amounts on bone mass changes and arterial calcification, 8-wk-old female Wistar rats were randomly placed in ovariectomized (OVX) control and OVX with vitamin D3 plus nicotine (VDN) treatment groups. The OVX with VDN rats were then divided into six groups to receive different amounts of Ca in their diets: 0.01%, 0.1%, 0.3%, 0.6%, 1.2%, or 2.4% Ca. After 8 wk of administration, low Ca intake groups with 0.01% and 0.1% Ca diets had significantly reduced bone mineral density (BMD) and bone mechanical properties as compared with those of the other groups, whereas high Ca intake groups with 1.2% and 2.4% Ca diets showed no differences as compared with the 0.6% Ca intake group. For both the 0.01% and 2.4% Ca intake groups, Ca levels in their thoracic arteries were significantly higher as compared with those of the 0.6% Ca diet group, and that was highly correlated with serum PTH levels. An increase in relative BMP-2 mRNA expression in the arterial tissues of the 0.01% and 2.4% Ca diet groups was also observed. These results suggested that extremely low Ca intake during periods of estrogen deficiency may be a possible risk for the complications of reduced BMD and arterial calcification and that extremely high Ca intake may promote arterial calcification with no changes in BMD.

  1. 'Extreme mass spectrometry': the role of mass spectrometry in the study of the Antarctic environment.

    Science.gov (United States)

    Magi, Emanuele; Tanwar, Shivani

    2014-11-01

    A focus on the studies of the Antarctic environment that have been performed by mass spectrometry is presented herein; our aim is to give evidence of the essential role of this instrumental technique in the framework of the scientific research in Antarctica, with a comprehensive review on the main literature of the last two decades. Due to the wideness of the topic, the present review is limited to the determination of organic pollutants, natural molecules and biomarkers in Antarctica, thus excluding elemental analysis and studies on inorganic species. The work has been divided into five sections, on the basis of the considered environmental compartment: air; ice and snow; seawater, pack ice and lakes; soil and sediments; and organisms and biomarkers.

  2. Alveolar bone mass in pre- and postmenopausal women with serum calcium as a marker: A comparative study

    Directory of Open Access Journals (Sweden)

    Amitha Ramesh

    2011-01-01

    Conclusion: Postmenopausal women exhibit a reduced alveolar bone mass and lowered levels of serum total calcium with the increasing age. These changes may be useful indicators for low skeletal bone mineral density or osteoporosis.

  3. SHIELD II: AGC 198507 - An Extremely Rare Low-Mass Galaxy Interaction?

    Science.gov (United States)

    Nikolina Borg Stevens, Karin; Cannon, John M.; McNichols, Andrew; McQuinn, Kristen B.; Teich, Yaron; SHIELD II Team

    2016-01-01

    The "Survey of HI in Extremely Low-mass Dwarfs II" ("SHIELD II") is a multiwavelength, legacy-class observational campaign that is facilitating the study of both internal and global evolutionary processes in low-mass dwarf galaxies discovered by the Arecibo Legacy Fast ALFA (ALFALFA) survey. New HST imaging of one of these sample galaxies, AGC 198507, has revealed it to be a very rare interacting system; to our knowledge this is one of only a few known interactions in this extreme mass range. WSRT imaging indicates that the bulk of the HI is associated with the more luminous AGC 198507, while low surface brightness gas extends toward and coincides with the less luminous companion, which is separated by roughly 1.5 kpc from AGC 198507. Here we present new VLA B configuration HI imaging that allows us to localize the HI gas, to examine the rotational dynamics of AGC 198507, and to study the nature of star formation in this unique low-mass interacting system.Support for this work was provided by NSF grant AST-1211683 to JMC at Macalester College, and by NASA through grant GO-13750 from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS5-26555.

  4. Bone mineral content has stronger association with lean mass than fat mass among Indian urban adolescents

    Directory of Open Access Journals (Sweden)

    Raman K Marwaha

    2015-01-01

    Full Text Available Introduction: There are conflicting reports on the relationship of lean mass (LM and fat mass (FM with bone mineral content (BMC. Given the high prevalence of Vitamin D deficiency in India, we planned the study to evaluate the relationship between LM and FM with BMC in Indian children and adolescents. The objective of the study was to evaluate the relationship of BMC with LM and FM. Materials and Methods: Total and regional BMC, LM, and FM using dual energy X-ray absorptiometry and pubertal staging were assessed in 1403 children and adolescents (boys [B]: 826; girls [G]: 577. BMC index, BMC/LM and BMC/FM ratio, were calculated. Results: The age ranged from 5 to 18 years, with a mean age of 13.2 ± 2.7 years. BMC adjusted for height (BMC index and BMC/height ratio was comparable in both genders. There was no difference in total BMC between genders in the prepubertal group but were higher in more advanced stages of pubertal maturation. The correlation of total as well as regional BMC was stronger for LM (B: Total BMC - 0.880, trunk - 0.715, leg - 0.894, arm - 0.891; G: Total BMC - 0.827, leg - 0.846, arm - 0.815 (all value indicate r2 , P < 0.0001 for all when compared with FM (B: Total BMC - 0.776, trunk - 0.676, leg - 0.772, arm - 0.728; G: Total BMC - 0.781, leg - 0.741, arm - 0.689; all P < 0.0001 except at trunk BMC (LM - 0.682 vs. FM - 0.721; all P < 0.0001, even after controlling for age, height, pubertal stage, and biochemical parameters. Conclusions: BMC had a stronger positive correlation with LM than FM.

  5. Risk factors for low bone mass in healthy young adults from North India: studies on BMD and bone turnover markers

    Directory of Open Access Journals (Sweden)

    Anita Fotedar Verma

    2015-04-01

    Full Text Available Background: Despite availability of adequate sunshine, Indian population has the highest prevalence of low bone mass and Bone Mineral Content (BMC. Risk factors for osteoporosis have been extensively studied in the west but poorly investigated in India. We studied BMD and Bone Turnover Markers (BTMs among healthy young adults. Methods: Fifty one healthy young adults (28 Males, 23 Females in the age group of 20-35 years were studied. Morphometric, biochemical parameters and BMD (whole body, spine, hip and wrist were recorded. Anthropometric measurements included height, weight, BMI and Waist/Hip Ratio (WHR. BTMs studied included - serum Bone-Specific Alkaline Phosphatase (sBAP, serum Collagen cross-linked C-Terminal telopeptide (sCTx, serum Osteocalcin (OC and human intact parathyroid hormone (hPTH using standard ELISA kits. Results: Of 51 healthy volunteers 21.57% had normal BMD, 13.73% were frankly osteoporotic and 64.70% were osteopenic. Age, weight and BMI were the best predictors of total BMD and BMC at all sites. sCTX positively correlated with Total Bone Area (TBA, BMD at Hip and Forearm. Using multiple regressions - age, weight, and BMI were significant predictors of BMD in young adults. Percentage body fat had inverse correlation with BMC, BMD and TBA. Weight and height positively correlated with BMD at femoral neck, inter-trochanter and Ward's triangle. Body weight was best predictor of BMD at femoral neck, Ward's triangle, forearm UD, forearm MID and forearm1/3. Conclusion: Majority of healthy young Indians have poor bone health as evidenced by bone markers. [Int J Res Med Sci 2015; 3(4.000: 933-939

  6. Normal bone mineral density and lean body mass, but increased fat mass, in young adult patients with congenital adrenal hyperplasia.

    NARCIS (Netherlands)

    Stikkelbroeck, M.M.L.; Oyen, W.J.G.; Wilt, G.J. van der; Hermus, A.R.M.M.; Otten, B.J.

    2003-01-01

    Patients with congenital adrenal hyperplasia attributable to 21-hydroxylase deficiency are treated with glucocorticoids. Glucocorticoid administration, even in substitution doses, may cause decreased bone mineral density (BMD) and obesity. The purpose of this study was to determine BMD, lean mass, a

  7. Body mass index, general fatness, lipid profile and bone mineral density in young women and men

    Directory of Open Access Journals (Sweden)

    Kopiczko Anna

    2017-03-01

    Full Text Available The bone tissue is metabolically active. Throughout the entire life, it undergoes changes in the form of bone resorption processes which are successive, with the participation of the resorbing cells and bone formation processes. The aim of the study was to evaluate mineral density and bone mass tissue and the lipid profile, BMI, total body fat in young females and males. The study involved 100 people (50 females and 50 males studying in Warsaw at the age of 23,2 ± 4,0 years. The densitometry method of the forearm was used for the assessment of bone mineral density (BMD and bone mass (BMC. The method of bioelectrical impedance was used for the assessment of body components. Basic body dimensions and indicators were assessed using anthropometric measurements. Body height, body mass and the needs for the densitometry study of the forearm were measured. The total cholesterol concentration was determined in the blood serum using diagnostic kits, as well as high-density lipoprotein (HDL-C and triglycerides. The concentration of the low-density lipoprotein (LDL-C was calculated. While in men the occurrence of a significant, positive correlation was stated between the concentration of the HDL cholesterol fraction and the mineral density and T-score index in the ultra-distal point, the analysis of the compounds of mineral density (BMD, bone mass (BMC of the forearm, T-score index with somatic features in women showed a significant, positive relation between the body weight and the bone mass mineral density and T-score indicator in the proximal point. Also, a significant weak, positive correlation was observed between the BMI, the mineral density and T-score indicator in the proximal point. In men, the occurrence of significant, positive correlations was stated between the body weight and BMC, BMD, T-score indicator in the proximal point of the forearm bone and ultra-distal point. Similar relations were observed between the BMI, mineral density, T

  8. Effect of Teriparatide, Vibration and the Combination on Bone Mass and Bone Architecture in Chronic Spinal Cord Injury

    Science.gov (United States)

    2015-12-01

    increasing bone mass and decreasing fractures in non- disabled populations of men and post-menopausal women but have not been examined in individuals with...Spinal Cord Injury PRINCIPAL INVESTIGATOR: Thomas J. Schnitzer, MD, PhD CONTRACTING ORGANIZATION: Northwestern University Evanston, IL 60208 REPORT...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Northwestern University 633 Clark St. Evanston,IL 60208-0001 AND ADDRESS(ES) 8. PERFORMING

  9. Resveratrol supplementation preserves long bone mass, microstructure, and strength in hindlimb-suspended old male rats.

    Science.gov (United States)

    Durbin, Stephanie M; Jackson, Janna R; Ryan, Michael J; Gigliotti, Joseph C; Alway, Stephan E; Tou, Janet C

    2014-01-01

    Resveratrol has gained popularity as an "anti-aging" compound due to its antioxidant and anti-inflammatory properties. Few studies have investigated the role of resveratrol supplementation in the prevention of age-related bone loss and skeletal disuse despite increased inactivity and age-related bone loss in the elderly. The objective of the study was to investigate the effect of resveratrol supplementation on disuse and age-related bone loss. Old (age 33 months) Fischer 344 × Brown Norway male rats were provided either trans-resveratrol (12.5 mg/kg bw/day) or deionized distilled water by oral gavage for 21 days. Rats were hindlimb-suspended (HLS) or kept ambulatory (AMB) for 14 days. Both femora and tibiae were collected. Bone mass was measured by dual-energy X-ray absorptiometry and bone microstructure was determined by micro-computed tomography. HLS of old male rats accelerated loss of bone mineral content, decreased trabecular bone volume per unit of total volume, and increased trabecular separation. Resveratrol supplementation ameliorated bone demineralization and loss of bone microarchitecture in HLS old male rats. The peak force measured by the three-point bending test was reduced (P = 0.007) in HLS/control compared to AMB/control rats. Resveratrol supplementation ameliorated HLS-induced loss of femur strength. Plasma osteocalcin and alkaline phosphatase was higher (P resveratrol. The bone protective effects of resveratrol appeared to be mediated through increased osteoblast bone formation, possibly due to reduced inflammation. Based on the results, resveratrol supplementation appeared to provide a feasible dietary therapy for preserving the skeletal system during disuse and age-related bone loss.

  10. Insights into relationships between body mass, composition and bone: findings in elite rugby players.

    Science.gov (United States)

    Hind, Karen; Gannon, Lisa; Brightmore, Amy; Beck, Belinda

    2015-01-01

    Recent reports indicate that bone strength is not proportional to body weight in obese populations. Elite rugby players have a similar body mass index (BMI) to obese individuals but differ markedly with low body fat, high lean mass, and frequent skeletal exposure to loading through weight-bearing exercise. The purpose of this study was to determine relationships between body weight, composition, and bone strength in male rugby players characterized by high BMI and high lean mass. Fifty-two elite male rugby players and 32 nonathletic, age-matched controls differing in BMI (30.2 ± 3.2 vs 24.1 ± 2.1 kg/m²; p = 0.02) received 1 total body and one total hip dual-energy X-ray absorptiometry scan. Hip structural analysis of the proximal femur was used to determine bone mineral density (BMD) and cross-sectional bone geometry. Multiple linear regression was computed to identify independent variables associated with total hip and femoral neck BMD and hip structural analysis-derived bone geometry parameters. Analysis of covariance was used to explore differences between groups. Further comparisons between groups were performed after normalizing parameters to body weight and to lean mass. There was a trend for a positive fat-bone relationship in rugby players, and a negative relationship in controls, although neither reached statistical significance. Correlations with lean mass were stronger for bone geometry (r(2): 0.408-0.520) than for BMD (r(2): 0.267-0.293). Relative to body weight, BMD was 6.7% lower in rugby players than controls (p Rugby players were heavier than controls, with greater lean mass and BMD (p rugby players (p rugby players was reduced in proportion to body weight and lean mass. However, their superior bone geometry suggests that overall bone strength may be adequate for loading demands. Fat-bone interactions in athletes engaged in high-impact sports require further exploration. Copyright © 2015. Published by Elsevier Inc.

  11. Adiponectin and peak bone mass in men: a cross-sectional, population-based study

    DEFF Research Database (Denmark)

    Frost, M; Abrahamsen, B; Nielsen, T L

    2010-01-01

    Adiponectin, a protein classically known to be secreted by adipocytes, is also secreted by bone-forming cells. Results of previous studies have been contradictory as to whether serum adiponectin and bone mineral density (BMD) are associated. The aim of this study was to investigate a possible...... association between serum adiponectin and BMD in young, healthy men at a time of peak bone mass. BMD in the femoral neck, total hip, and lumbar spine were measured in this population-based cross-sectional study of 700 men aged 20-29 years participating in the Odense Androgen Study. Magnetic resonance imaging...... of femoral cortical thickness and bone marrow size was performed in a subsample of 363 participants. The associations between serum adiponectin and various bone measures were investigated by means of regression analyses with adjustment for potential confounding variables. An inverse association was found...

  12. Detection of rheumatoid arthritis bone erosions by 2 different dedicated extremity MRI units and conventional radiography

    DEFF Research Database (Denmark)

    Duer, Anne; Vestergaard, Aage; Døhn, Uffe Møller;

    2008-01-01

    and carpal bones. MagneVu and CR detected 100% and 89%, respectively, of large erosions (OMERACT-RAMRIS-score > 1 on Artoscan) in MCP-joints, and 69% and 15.8% of large erosions in wrists. CONCLUSIONS: Both E-MRI units detected more erosions than CR, particularly due to a higher sensitivity in metacarpal...... heads and carpal bones. The MagneVu detected fewer erosions than the Artoscan, due to a lower average image quality and a smaller proportion of bones being visualized....

  13. Female Mice Lacking Estrogen Receptor-α in Hypothalamic Proopiomelanocortin (POMC) Neurons Display Enhanced Estrogenic Response on Cortical Bone Mass.

    Science.gov (United States)

    Farman, H H; Windahl, S H; Westberg, L; Isaksson, H; Egecioglu, E; Schele, E; Ryberg, H; Jansson, J O; Tuukkanen, J; Koskela, A; Xie, S K; Hahner, L; Zehr, J; Clegg, D J; Lagerquist, M K; Ohlsson, C

    2016-08-01

    Estrogens are important regulators of bone mass and their effects are mainly mediated via estrogen receptor (ER)α. Central ERα exerts an inhibitory role on bone mass. ERα is highly expressed in the arcuate (ARC) and the ventromedial (VMN) nuclei in the hypothalamus. To test whether ERα in proopiomelanocortin (POMC) neurons, located in ARC, is involved in the regulation of bone mass, we used mice lacking ERα expression specifically in POMC neurons (POMC-ERα(-/-)). Female POMC-ERα(-/-) and control mice were ovariectomized (OVX) and treated with vehicle or estradiol (0.5 μg/d) for 6 weeks. As expected, estradiol treatment increased the cortical bone thickness in femur, the cortical bone mechanical strength in tibia and the trabecular bone volume fraction in both femur and vertebrae in OVX control mice. Importantly, the estrogenic responses were substantially increased in OVX POMC-ERα(-/-) mice compared with the estrogenic responses in OVX control mice for cortical bone thickness (+126 ± 34%, P mass, ERα was silenced using an adeno-associated viral vector. Silencing of ERα in hypothalamic VMN resulted in unchanged bone mass. In conclusion, mice lacking ERα in POMC neurons display enhanced estrogenic response on cortical bone mass and mechanical strength. We propose that the balance between inhibitory effects of central ERα activity in hypothalamic POMC neurons in ARC and stimulatory peripheral ERα-mediated effects in bone determines cortical bone mass in female mice.

  14. Analysis of a Fossil Bone from the Archaeological Settlement Malu Rosu, Romania by Accelerator Mass Spectrometry

    CERN Document Server

    Olariu, A; Hellborg, R; Stenström, K; Faarinen, M P; Persson, P; Erlandsson, B; Skog, G; Alexandrescu, E; Olariu, Agata; Popescu, Ion V.; Hellborg, Ragnar; Stenstr\\"om, Kristina; Faarinen, Mikko; Persson, Per; Erlandsson, Bengt; Alexandrescu, Emilian

    2001-01-01

    A fossil bone from the archaeological site Malu Rosu Giurgiu, in Romania has been analyzed by accelerator mass spectrometry to estimate its age by determining its $^{14}$C content. The radiocarbon age of the bone is in agreement with the date obtained by the method for age determination, based on fluorine content. This is the first radiocarbon dating for the final Neolithic period, for this archaeological settlement in the Romanian region.

  15. Genetic and environmental factors affecting peak bone mass in premenopausal Japanese women

    OpenAIRE

    Hayakawa, Yoshika; Yanagi, Hisako; Hara, Shuichi; Amagai, Hitoshi; Endo, Kazue; Hamaguchi, Hideo; Tomura, Shigeo

    2001-01-01

    The purpose of this study was to examine the relationships between peak bone mass and genetic and environmental factors. We measured whole-body bone mineral density (BMD), lumbar spine BMD, and radius BMD with dual-energy X-ray absorptiometry (DXA) and analyzed eight genetic factors: vitamin D receptor (VDR)-3′, VDR-5′, estrogen receptor (ER), calcitonin receptor (CTR), parathyroid hormone (PTH), osteocalcin (OC), apolipoprotein E (ApoE), and fatty acid binding protein 2 (FABP2) allelic polym...

  16. Bisphosphonates improve trabecular bone mass and normalize cortical thickness in ovariectomized, osteoblast connexin43 deficient mice.

    Science.gov (United States)

    Watkins, Marcus P; Norris, Jin Yi; Grimston, Susan K; Zhang, Xiaowen; Phipps, Roger J; Ebetino, Frank H; Civitelli, Roberto

    2012-10-01

    The gap junction protein, connexin43 (Cx43) controls both bone formation and osteoclastogenesis via osteoblasts and/or osteocytes. Cx43 has also been proposed to mediate an anti-apoptotic effect of bisphosphonates, potent inhibitors of bone resorption. We studied whether bisphosphonates are effective in protecting mice with a conditional Cx43 gene deletion in osteoblasts and osteocytes (cKO) from the consequences of ovariectomy on bone mass and strength. Ovariectomy resulted in rapid loss of trabecular bone followed by a slight recovery in wild type (WT) mice, and a similar degree of trabecular bone loss, albeit slightly delayed, occurred in cKO mice. Treatment with either risedronate (20 μg/kg) or alendronate (40 μg/kg) prevented ovariectomy-induced bone loss in both genotypes. In basal conditions, bones of cKO mice have larger marrow area, higher endocortical osteoclast number, and lower cortical thickness and strength relative to WT. Ovariectomy increased endocortical osteoclast number in WT but not in cKO mice. Both bisphosphonates prevented these increases in WT mice, and normalized endocortical osteoclast number, cortical thickness and bone strength in cKO mice. Thus, lack of osteoblast/osteocyte Cx43 does not alter bisphosphonate action on bone mass and strength in estrogen deficiency. These results support the notion that one of the main functions of Cx43 in cortical bone is to restrain osteoblast and/or osteocytes from inducing osteoclastogenesis at the endocortical surface. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Aryl hydrocarbon receptors in osteoclast lineage cells are a negative regulator of bone mass.

    Directory of Open Access Journals (Sweden)

    Tai-yong Yu

    Full Text Available Aryl hydrocarbon receptors (AhRs play a critical role in various pathological and physiological processes. Although recent research has identified AhRs as a key contributor to bone metabolism following studies in systemic AhR knockout (KO or transgenic mice, the cellular and molecular mechanism(s in this process remain unclear. In this study, we explored the function of AhR in bone metabolism using AhR(RANKΔOc/ΔOc (RANK(Cre/+;AhR(flox/flox mice. We observed enhanced bone mass together with decreased resorption in both male and female 12 and 24-week-old AhR(RANKΔOc/ΔOc mice. Control mice treated with 3-methylcholanthrene (3MC, an AhR agonist, exhibited decreased bone mass and increased bone resorption, whereas AhR(CtskΔOc/ΔOc (Ctsk(Cre/+;AhR(flox/flox mice injected with 3MC appeared to have a normal bone phenotype. In vitro, bone marrow-derived macrophages (BMDMs from AhR(RANKΔOc/ΔOc mice exhibited impaired osteoclastogenesis and repressed differentiation with downregulated expression of B lymphocyte-induced maturation protein 1 (Blimp1, and cytochrome P450 genes Cyp1b1 and Cyp1a2. Collectively, our results not only demonstrated that AhR in osteoclast lineage cells is a physiologically relevant regulator of bone resorption, but also highlighted the need for further studies on the skeletal actions of AhR inhibitors in osteoclast lineage cells commonly associated with bone diseases, especially diseases linked to environmental pollutants known to induce bone loss.

  18. The mammalian lectin galectin-8 induces RANKL expression, osteoclastogenesis, and bone mass reduction in mice

    Science.gov (United States)

    Vinik, Yaron; Shatz-Azoulay, Hadas; Vivanti, Alessia; Hever, Navit; Levy, Yifat; Karmona, Rotem; Brumfeld, Vlad; Baraghithy, Saja; Attar-Lamdar, Malka; Boura-Halfon, Sigalit; Bab, Itai; Zick, Yehiel

    2015-01-01

    Skeletal integrity is maintained by the co-ordinated activity of osteoblasts, the bone-forming cells, and osteoclasts, the bone-resorbing cells. In this study, we show that mice overexpressing galectin-8, a secreted mammalian lectin of the galectins family, exhibit accelerated osteoclasts activity and bone turnover, which culminates in reduced bone mass, similar to cases of postmenopausal osteoporosis and cancerous osteolysis. This phenotype can be attributed to a direct action of galectin-8 on primary cultures of osteoblasts that secrete the osteoclastogenic factor RANKL upon binding of galectin-8. This results in enhanced differentiation into osteoclasts of the bone marrow cells co-cultured with galectin-8-treated osteoblasts. Secretion of RANKL by galectin-8-treated osteoblasts can be attributed to binding of galectin-8 to receptor complexes that positively (uPAR and MRC2) and negatively (LRP1) regulate galectin-8 function. Our findings identify galectins as new players in osteoclastogenesis and bone remodeling, and highlight a potential regulation of bone mass by animal lectins. DOI: http://dx.doi.org/10.7554/eLife.05914.001 PMID:25955862

  19. Reduced bone mass and muscle strength in male 5α-reductase type 1 inactivated mice.

    Directory of Open Access Journals (Sweden)

    Sara H Windahl

    Full Text Available Androgens are important regulators of bone mass but the relative importance of testosterone (T versus dihydrotestosterone (DHT for the activation of the androgen receptor (AR in bone is unknown. 5α-reductase is responsible for the irreversible conversion of T to the more potent AR activator DHT. There are two well established isoenzymes of 5α-reductase (type 1 and type 2, encoded by separate genes (Srd5a1 and Srd5a2. 5α-reductase type 2 is predominantly expressed in male reproductive tissues whereas 5α-reductase type 1 is highly expressed in liver and moderately expressed in several other tissues including bone. The aim of the present study was to investigate the role of 5α-reductase type 1 for bone mass using Srd5a1⁻/⁻ mice. Four-month-old male Srd5a1⁻/⁻ mice had reduced trabecular bone mineral density (-36%, p<0.05 and cortical bone mineral content (-15%, p<0.05 but unchanged serum androgen levels compared with wild type (WT mice. The cortical bone dimensions were reduced in the male Srd5a1⁻/⁻ mice as a result of a reduced cortical periosteal circumference compared with WT mice. T treatment increased the cortical periosteal circumference (p<0.05 in orchidectomized WT mice but not in orchidectomized Srd5a1⁻/⁻ mice. Male Srd5a1⁻/⁻ mice demonstrated a reduced forelimb muscle grip strength compared with WT mice (p<0.05. Female Srd5a1⁻/⁻ mice had slightly increased cortical bone mass associated with elevated circulating levels of androgens. In conclusion, 5α-reductase type 1 inactivated male mice have reduced bone mass and forelimb muscle grip strength and we propose that these effects are due to lack of 5α-reductase type 1 expression in bone and muscle. In contrast, the increased cortical bone mass in female Srd5a1⁻/⁻ mice, is an indirect effect mediated by elevated circulating androgen levels.

  20. Perturbative effects of spinning black holes in the extreme mass-ratio limit

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Hiroyuki; Campanelli, Manuela; Lousto, Carlos O; Zlochower, Yosef, E-mail: nakano@astro.rit.edu, E-mail: manuela@astro.rit.edu, E-mail: lousto@astro.rit.edu, E-mail: yosef@astro.rit.edu [Center for Computational Relativity and Gravitation, School of Mathematical Sciences, Rochester Institute of Technology, Rochester, NY 14623 (United States)

    2011-07-07

    Recently, we proposed an enhancement of the Regge-Wheeler-Zerilli formalism for first-order perturbations about a Schwarzschild background that includes first-order corrections due to the background black-hole spin in the black-hole perturbation approach. Using this formalism, we analytically investigate gravitational wave emission and linear momentum flux from a head-on collision of two spinning black holes in the extreme mass-ratio limit. The result derived in the lowest slow-motion and weak-field approximations here is consistent with the post-Newtonian calculation.

  1. ASAS J083241+2332.4: A NEW EXTREME LOW MASS RATIO OVERCONTACT BINARY SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Sriram, K.; Malu, S.; Vivekananda Rao, P. [Department of Astronomy, Osmania University, Hyderabad 500007 (India); Choi, C. S., E-mail: astrosriram@yahoo.co.in [Korea Astronomy and Space Science Institute, Daejeon 34055 (Korea, Republic of)

    2016-03-15

    We present the R- and V-band CCD photometry and Hα line studies of an overcontact binary ASAS J083241+2332.4. The light curves exhibit totality along with a trace of the O’Connell effect. The photometric solution indicates that this system falls into the category of extreme low-mass ratio overcontact binaries with a mass ratio, q ∼ 0.06. Although a trace of the O’ Connell effect is observed, constancy of the Hα line along various phases suggest that a relatively higher magnetic activity is needed for it to show a prominent fill-in effect. The study of O–C variations reveals that the period of the binary shows a secular increase at the rate of dP/dt ∼ 0.0765 s years{sup −1}, which is superimposed by a low, but significant, sinusoidal modulation with a period of ∼8.25 years. Assuming that the sinusoidal variation is due to the presence of a third body, orbital elements have been derived. There exist three other similar systems, SX Crv, V857 Her, and E53, which have extremely low mass ratios and we conclude that ASAS J083241+2332.4 resembles SX Crv in many respects. Theoretical studies indicate that at a critical mass ratio range, q{sub critical} = 0.07–0.09, overcontact binaries should merge and form a fast rotating star, but it has been suggested that q{sub critical} can continue to fall up to 0.05 depending on the primary's mass and structure. Moreover, the obtained fill-out factors (50%–70%) indicate that mass loss is considerable and hydrodynamical simulations advocate that mass loss from L{sub 2} is mandatory for a successful merging process. Comprehensively, the results indicate that ASAS J083241+2332.4 is at a stage of merger. The pivotal role played by the subtle nature of the derived mass ratio in forming a rapidly rotating star has been discussed.

  2. Thin healthy women have a similar low bone mass to women with anorexia nervosa.

    Science.gov (United States)

    Fernández-García, D; Rodríguez, M; García Alemán, J; García-Almeida, J M; Picón, M J; Fernández-Aranda, F; Tinahones, F J

    2009-09-01

    An association between anorexia nerviosa (AN) and low bone mass has been demonstrated. Bone loss associated with AN involves hormonal and nutritional impairments, though their exact contribution is not clearly established. We compared bone mass in AN patients with women of similar weight with no criteria for AN, and a third group of healthy, normal-weight, age-matched women. The study included forty-eight patients with AN, twenty-two healthy eumenorrhoeic women with low weight (LW group; BMI 18.5 kg/m2 (control group), all of similar age. We measured lean body mass, percentage fat mass, total bone mineral content (BMC) and bone mineral density in lumbar spine (BMD LS) and in total (tBMD). We measured anthropometric parameters, leptin and growth hormone. The control group had greater tBMD and BMD LS than the other groups, with no differences between the AN and LW groups. No differences were found in tBMD, BMD LS and total BMC between the restrictive (n 25) and binge-purge type (n 23) in AN patients. In AN, minimum weight (P = 0.002) and percentage fat mass (P = 0.02) explained BMD LS variation (r2 0.48) and minimum weight (r2 0.42; P = 0.002) for tBMD in stepwise regression analyses. In the LW group, BMI explained BMD LS (r2 0.72; P = 0.01) and tBMD (r2 0.57; P = 0.04). We concluded that patients with AN had similar BMD to healthy thin women. Anthropometric parameters could contribute more significantly than oestrogen deficiency in the achievement of peak bone mass in AN patients.

  3. Effect of age and disease on bone mass in Japanese patients with schizophrenia

    Directory of Open Access Journals (Sweden)

    Sugawara Norio

    2012-02-01

    Full Text Available Abstract Background There have been a limited number of studies comparing bone mass between patients with schizophrenia and the general population. The aim of this study was to compare the bone mass of schizophrenia patients with that of healthy subjects in Japan. Methods We recruited patients (n = 362, aged 48.8 ± 15.4 (mean ± SD years who were diagnosed with schizophrenia or schizoaffective disorder based on the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV. Bone mass was measured using quantitative ultrasound densitometry of the calcaneus. The osteosono-assessment index (OSI was calculated as a function of the speed of sound and the transmission index. For comparative analysis, OSI data from 832 adults who participated in the Iwaki Health Promotion Project 2009 was used as representative of the general community. Results Mean OSI values among male schizophrenic patients were lower than those in the general population in the case of individuals aged 40 and older. In females, mean OSI values among schizophrenic patients were lower than those in the general community in those aged 60 and older. In an analysis using the general linear model, a significant interaction was observed between subject groups and age in males. Conclusions Older schizophrenic patients exhibit lower bone mass than that observed in the general population. Our data also demonstrate gender and group differences among schizophrenic patients and controls with regard to changes in bone mass associated with aging. These results indicate that intervention programs designed to delay or prevent decreased bone mass in schizophrenic patients might be tailored according to gender.

  4. Drynaria fortunei J. Sm. improves the bone mass of ovariectomized rats through osteocalcin-involved endochondral ossification.

    Science.gov (United States)

    Lee, Yong-Eng; Liu, Hwa-Chang; Lin, Yi-Ling; Liu, Shing-Hwa; Yang, Rong-Sen; Chen, Ruei-Ming

    2014-12-02

    Our previous study showed that Drynaria fortunei J. Sm. (Kunze), a traditional Chinese medical herb, can promote osteoblast differentiation and maturation. This study was further aimed to confirm the traditional effects of Kunze on the bone mass of ovariectomized rats. Female Wistar rats were given an ovariectomy and then administered the water extract of Kunze (WEK). Systemic and tissue toxicities of WEK were assessed. A biomechanical test, bone mineral contents, and bone histomorphometry were analyzed to determine the effects of the WEK on the bone mass. Levels of osteocalcin (OCN) in bone tissues were determined by immunohistochemistry and immunoblotting. The effects of naringin, one of the bioactive compounds of the WEK, on the bone mass were evaluated. A bilateral ovariectomy in rats caused a time-dependent decrease in levels of serum 17β-estradiol. Exposure of ovariectomized rats to the WEK at 0.5 and 1g/kg body weight/day for 1, 2, 3, and 6 months did not induce systemic or tissue toxicities. Biomechanical testing and a bone mineral content analysis showed that the ovariectomy decreased the bone torsion force and bone ash in time-dependent manners. In comparison, after exposure to the WEK, the ovariectomy-induced reductions in the bone torsion force and bone ash were significantly alleviated. In parallel, results of a bone histomorphometric assay further revealed that the ovariectomy caused significant diminution in the production of prehypertrophic chondrocytes and trabecular bone but enhanced hypertrophic chondrocyte numbers in the growth plate. However, exposure to the WEK lowered ovariectomy-induced changes in these cellular events. As to the mechanism, the WEK increased OCN biosynthesis in bone tissues of ovariectomized rats. Administration of naringin to ovariectomized rats caused significant amelioration of the bone strength, bone mineral contents, and trabecular bone amounts. This study shows that the WEK can translationally promote the bone mass in

  5. An extremely sensitive species-specific ARMs PCR test for the presence of tiger bone DNA.

    Science.gov (United States)

    Wetton, Jon H; Tsang, Carol S F; Roney, Chris A; Spriggs, Adrian C

    2004-02-10

    The survival of the tiger (Panthera tigris) is seriously threatened by poaching to provide raw materials for Traditional Chinese Medicines (TCMs). Most highly prized are the tiger's bones, which are used in combination with other animal and plant derivatives in pills and plasters for the treatment of rheumatism and other ailments. Hundreds of patent remedies have been produced which claim to contain tiger bone, but proof of its presence is needed, if legislation prohibiting the trade in endangered species is to be enforced. A highly sensitive tiger-specific real-time PCR assay has been developed to address this problem. Using primers specific to the tiger mitochondrial cytochrome b gene, successful amplification has been reliably achieved from blood, hair and bone as well as from a range of TCMs spiked with 0.5% tiger bone. Although capable of detecting fewer than 10 substrate molecules, the seven varieties of TCM pills and plasters tested showed no detectable trace of tiger DNA before spiking. Furthermore, sequencing several "tiger bone" fragments seized from TCM shops has shown that they actually originated from cattle and pigs. The potential effects of traditional bone preparation methods, evidence that much lower concentrations are used than alleged on TCM packaging, and substitution of bones from other species all suggest a low likelihood of detecting tiger DNA in patent medicines. Despite this, the basic methods have been thoroughly proven and can be readily applied to derivatives from other CITES protected species providing a rapid and highly sensitive forensic test for species of origin. Potential applications to the monitoring of wild populations are demonstrated by the successful identification of shed hairs and faecal samples.

  6. First four-color photometric investigation of extreme mass-ratio contact binary AS coronae borealis

    Science.gov (United States)

    Liu, Liang; Qian, Shengbang; Zhu, Liying; Liao, Wenping; He, Jiajia; Liu, Nianping

    2017-02-01

    The first high-precision BVRI light curves of the eclipsing binary AS CrB were presented and were analyzed by the 2015 version of the W-D code. It is found that AS CrB is an extreme mass-ratio, deep contact binary with a fill-out factor of f = 59.6 ± 2.5 % and a mass ratio of q = 0.172 ± 0.008 . Based on the photometric solution and the Dartmouth isochrones model, the masses, radii, and luminosities of the components are estimated as follows: M1 = 1.25 ± 0.15M⊙ , M2 = 0.21 ± 0.06M⊙ , R1 = 1.40 ± 0.07R⊙ , R2 = 0.67 ± 0.04R⊙ , L1 = 3.2 ± 0.2L⊙ , and L2 = 0.72 ± 0.04L⊙ , with an estimated distance 459 ± 42 pc. These uncertainties mainly come from the errors of the color used to estimate the temperature of the primary star. By investigating all of the available times of light minima, it is found that the Observed-Calculated [(O - C) ] curve shows a long-term period increase, with a rate of dP / dt = +(3.46 ± 0.01) ×10-7 day/year. As an extreme mass-ratio contact binary, AS CrB may merge into a single star, such as an FK Com-type star or a blue straggler, because of the orbital instability.

  7. Changes in lower extremity muscle mass and muscle strength after weight loss in obese patients with knee osteoarthritis

    DEFF Research Database (Denmark)

    Henriksen, Marius; Christensen, Robin; Danneskiold-Samsøe, Bente

    2012-01-01

    To investigate the effects of low-energy diet-induced weight loss on lower-extremity muscle mass and knee muscle strength in obese patients with knee osteoarthritis (OA), and the associations of these effects.......To investigate the effects of low-energy diet-induced weight loss on lower-extremity muscle mass and knee muscle strength in obese patients with knee osteoarthritis (OA), and the associations of these effects....

  8. Assessment of image quality in soft tissue and bone visualization tasks for a dedicated extremity cone-beam CT system

    Energy Technology Data Exchange (ETDEWEB)

    Demehri, S. [Johns Hopkins University, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Johns Hopkins Outpatient Center, JHOC 5168, Musculoskeletal Radiology, Baltimore, MD (United States); Muhit, A.; Zbijewski, W.; Stayman, J.W. [Johns Hopkins University, Department of Biomedical Engineering, Baltimore, MD (United States); Yorkston, J.; Packard, N.; Senn, R.; Yang, D.; Foos, D. [Carestream Health, Rochester, NY (United States); Thawait, G.K.; Fayad, L.M.; Chhabra, A.; Carrino, J.A. [Johns Hopkins University, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Siewerdsen, J.H. [Johns Hopkins University, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Johns Hopkins University, Department of Biomedical Engineering, Baltimore, MD (United States)

    2015-06-01

    To assess visualization tasks using cone-beam CT (CBCT) compared to multi-detector CT (MDCT) for musculoskeletal extremity imaging. Ten cadaveric hands and ten knees were examined using a dedicated CBCT prototype and a clinical multi-detector CT using nominal protocols (80kVp-108mAs for CBCT; 120kVp- 300mAs for MDCT). Soft tissue and bone visualization tasks were assessed by four radiologists using five-point satisfaction (for CBCT and MDCT individually) and five-point preference (side-by-side CBCT versus MDCT image quality comparison) rating tests. Ratings were analyzed using Kruskal-Wallis and Wilcoxon signed-rank tests, and observer agreement was assessed using the Kappa-statistic. Knee CBCT images were rated ''excellent'' or ''good'' (median scores 5 and 4) for ''bone'' and ''soft tissue'' visualization tasks. Hand CBCT images were rated ''excellent'' or ''adequate'' (median scores 5 and 3) for ''bone'' and ''soft tissue'' visualization tasks. Preference tests rated CBCT equivalent or superior to MDCT for bone visualization and favoured the MDCT for soft tissue visualization tasks. Intraobserver agreement for CBCT satisfaction tests was fair to almost perfect (κ ∝ 0.26-0.92), and interobserver agreement was fair to moderate (κ ∝ 0.27-0.54). CBCT provided excellent image quality for bone visualization and adequate image quality for soft tissue visualization tasks. (orig.)

  9. Improved analytic extreme-mass-ratio inspiral model for scoping out eLISA data analysis

    CERN Document Server

    Chua, Alvin J K

    2015-01-01

    The space-based gravitational-wave detector eLISA has been selected as the ESA L3 mission, and the mission design will be finalised by the end of this decade. To prepare for mission formulation over the next few years, several outstanding and urgent questions in data analysis will be addressed using mock data challenges, informed by instrument measurements from the LISA Pathfinder satellite launching at the end of 2015. These data challenges will require accurate and computationally affordable waveform models for anticipated sources such as the extreme-mass-ratio inspirals (EMRIs) of stellar-mass compact objects into massive black holes. Previous data challenges have made use of the well-known analytic EMRI waveforms of Barack and Cutler, which are extremely quick to generate but dephase relative to more accurate waveforms within hours, due to their mismatched radial, polar and azimuthal frequencies. In this paper, we describe an augmented Barack-Cutler model that uses a frequency map to the correct Kerr freq...

  10. Lifetime Calculations on Collector Optics from Laser Plasma Extreme Ultraviolet Sources with Minimum Mass

    Institute of Scientific and Technical Information of China (English)

    WU Tao; WANG Xin-Bing

    2011-01-01

    An ion flux and its kinetic energy spectrum are obtained using a self similar spherically symmetric fluid model of expansion of a collisionless plasma into vacuum. According to the ion flux and energy distribution, the collector optical lifetime is estimated by knowledge of the sputtering yield of conventional Mo/Si multilayer coatings for the CO2 and Nd:YAG pulsed-laser produced plasmas based on the minimum mass tin droplet target without debris mitigation. The results show that the longer wavelength of the CO2 laser produced plasma light source is more suitable for extreme ultraviolet lithography than Nd:YAG laser in respect of fast ion debris induced sputtering damage to the collector mirror.%@@ An ion flux and its kinetic energy spectrum are obtained using a self similar spherically symmetric fluid model of expansion of a collisionless plasma into vacuum.According to the ion flux and energy distribution,the collector optical lifetime is estimated by knowledge of the sputtering yield of conventional Mo/Si multilayer coatings for the CO2 and Nd:YAG pulsed-laser produced plasmas based on the minimum mass tin droplet target without debris mitigation.The results show that the longer wavelength of the CO2 laser produced plasma light source is more suitable for extreme ultraviolet lithography than Nd:YAG laser in respect of fast ion debris induced sputtering damage to the collector mirror.

  11. Neuropeptide Y knockout mice reveal a central role of NPY in the coordination of bone mass to body weight.

    Directory of Open Access Journals (Sweden)

    Paul A Baldock

    Full Text Available Changes in whole body energy levels are closely linked to alterations in body weight and bone mass. Here, we show that hypothalamic signals contribute to the regulation of bone mass in a manner consistent with the central perception of energy status. Mice lacking neuropeptide Y (NPY, a well-known orexigenic factor whose hypothalamic expression is increased in fasting, have significantly increased bone mass in association with enhanced osteoblast activity and elevated expression of bone osteogenic transcription factors, Runx2 and Osterix. In contrast, wild type and NPY knockout (NPY (-/- mice in which NPY is specifically over expressed in the hypothalamus (AAV-NPY+ show a significant reduction in bone mass despite developing an obese phenotype. The AAV-NPY+ induced loss of bone mass is consistent with models known to mimic the central effects of fasting, which also show increased hypothalamic NPY levels. Thus these data indicate that, in addition to well characterized responses to body mass, skeletal tissue also responds to the perception of nutritional status by the hypothalamus independently of body weight. In addition, the reduction in bone mass by AAV NPY+ administration does not completely correct the high bone mass phenotype of NPY (-/- mice, indicating the possibility that peripheral NPY may also be an important regulator of bone mass. Indeed, we demonstrate the expression of NPY specifically in osteoblasts. In conclusion, these data identifies NPY as a critical integrator of bone homeostatic signals; increasing bone mass during times of obesity when hypothalamic NPY expression levels are low and reducing bone formation to conserve energy under 'starving' conditions, when hypothalamic NPY expression levels are high.

  12. Effects of a 6-month football intervention program on bone mass and physical fitness in overweight children

    DEFF Research Database (Denmark)

    Seabra, André; Serra, Hugo; Seabra, Ana

    2016-01-01

    at school. Bone mass indicators included whole-boy and lumbar spine bone mineral density (BMD) and bone mineral content (BMC). Physical fitness tests included 5- and 30-m sprints, countermovement jump (CMJ), and Yo-Yo intermittent endurance test level 1 (Yo-Yo IE1). Body composition was evaluated using dual...

  13. Fetal and childhood growth patterns associated with bone mass in school-age children: The generation R study

    NARCIS (Netherlands)

    D.H.M. Heppe (Denise); M.C. Medina-Gomez (Carolina); J.C. de Jongste (Johan); H. Raat (Hein); E.A.P. Steegers (Eric); A. Hofman (Albert); F. Rivadeneira Ramirez (Fernando); V.W.V. Jaddoe (Vincent)

    2014-01-01

    textabstractLow birth weight is associated with lower bone accrual in children and peak bone mass in adults. We assessed how different patterns of longitudinal fetal and early childhood growth influence bone properties at school age. In 5431 children participating in a population-based prospective

  14. A cosmological view of extreme mass-ratio inspirals in nuclear star clusters

    CERN Document Server

    Mapelli, M; Vecchio, A; Graham, Alister W; Gualandris, A

    2012-01-01

    There is increasing evidence that many galaxies host both a nuclear star cluster (NC) and a super-massive black hole (SMBH). Their coexistence is particularly prevalent in spheroids with stellar mass 10^8-10^10 solar masses. We study the possibility that a stellar-mass black hole (BH) hosted by a NC inspirals and merges with the central SMBH. Due to the high stellar density in NCs, extreme mass-ratio inspirals (EMRIs) of BHs onto SMBHs in NCs may be important sources of gravitational waves (GWs). We consider sensitivity curves for three different space-based GW laser interferometric mission concepts: the Laser Interferometer Space Antenna (LISA), the New Gravitational wave Observatory (NGO) and the DECi-hertz Interferometer Gravitational wave Observatory (DECIGO). We predict that, under the most optimistic assumptions, LISA and DECIGO will detect up to thousands of EMRIs in NCs per year, while NGO will observe up to tens of EMRIs per year. We explore how a number of factors may affect the predicted rates. In ...

  15. A New Class of Nascent Eclipsing Binaries with Extreme Mass Ratios

    CERN Document Server

    Moe, Maxwell

    2014-01-01

    Early B-type main-sequence (MS) stars (M$_1$ = 5-16 M$_{\\odot}$) with closely orbiting low-mass stellar companions (q = M$_2$/M$_1$ < 0.25) can evolve to produce Type Ia supernovae, low-mass X-ray binaries, and millisecond pulsars. However, the formation mechanism and intrinsic frequency of such close extreme mass-ratio binaries have been debated, especially considering none have hitherto been detected. Utilizing observations of the Large Magellanic Cloud galaxy conducted by the Optical Gravitational Lensing Experiment, we have discovered a new class of eclipsing binaries in which a luminous B-type MS star irradiates a closely orbiting low-mass pre-MS companion that has not yet fully formed. The primordial pre-MS companions have large radii and discernibly reflect much of the light they intercept from the B-type MS primaries ($\\Delta$I$_{\\rm refl}$ = 0.02-0.14 mag). For the 18 definitive MS + pre-MS eclipsing binaries in our sample with good model fits to the observed light curves, we measure short orbital...

  16. Effects of different types of jump impact on trabecular bone mass and microarchitecture in growing rats.

    Directory of Open Access Journals (Sweden)

    Yong-In Ju

    Full Text Available Substantial evidence from animal studies indicates that jumping increases bone mass and strength. However, most studies have focused on the take-off, rather than the landing phase of jumps. Thus, we compared the effects of landing and upward jump impact on trabecular bone mass and microarchitecture. Male Wistar rats aged 10 weeks were randomly assigned to the following groups: sedentary control (CON, 40-cm upward jumps (40UJ; 40-cm drop jumps (40DJ; and 60-cm drop jumps (60DJ (n = 10 each. The upward jump protocol comprised 10 upward jumps/day, 5 days/week for 8 weeks to a height of 40 cm. The drop jump protocol comprised dropping rats from a height of 40 or 60 cm at the same frequency and time period as the 40UJ group. Trabecular bone mass, architecture, and mineralization at the distal femoral metaphysis were evaluated using microcomputed tomography. Ground reaction force (GRF was measured using a force platform. Bone mass was significantly higher in the 40UJ group compared with the DJ groups (+49.1% and +28.3%, respectively, although peak GRF (-57.8% and -122.7%, respectively and unit time force (-21.6% and -36.2%, respectively were significantly lower in the 40UJ group. These results showed that trabecular bone mass in growing rats is increased more effectively by the take-off than by the landing phases of jumps and suggest that mechanical stress accompanied by muscle contraction would be more important than GRF as an osteogenic stimulus. However, the relevance of these findings to human bone physiology is unclear and requires further study.

  17. High bone mass in mice lacking Cx37 because of defective osteoclast differentiation.

    Science.gov (United States)

    Pacheco-Costa, Rafael; Hassan, Iraj; Reginato, Rejane D; Davis, Hannah M; Bruzzaniti, Angela; Allen, Matthew R; Plotkin, Lilian I

    2014-03-21

    Connexin (Cx) proteins are essential for cell differentiation, function, and survival in all tissues with Cx43 being the most studied in bone. We now report that Cx37, another member of the connexin family of proteins, is expressed in osteoclasts, osteoblasts, and osteocytes. Mice with global deletion of Cx37 (Cx37(-/-)) exhibit higher bone mineral density, cancellous bone volume, and mechanical strength compared with wild type littermates. Osteoclast number and surface are significantly lower in bone of Cx37(-/-) mice. In contrast, osteoblast number and surface and bone formation rate in bones from Cx37(-/-) mice are unchanged. Moreover, markers of osteoblast activity ex vivo and in vivo are similar to those of Cx37(+/+) littermates. sRANKL/M-CSF treatment of nonadherent Cx37(-/-) bone marrow cells rendered a 5-fold lower level of osteoclast differentiation compared with Cx37(+/+) cell cultures. Further, Cx37(-/-) osteoclasts are smaller and have fewer nuclei per cell. Expression of RANK, TRAP, cathepsin K, calcitonin receptor, matrix metalloproteinase 9, NFATc1, DC-STAMP, ATP6v0d1, and CD44, markers of osteoclast number, fusion, or activity, is lower in Cx37(-/-) osteoclasts compared with controls. In addition, nonadherent bone marrow cells from Cx37(-/-) mice exhibit higher levels of markers for osteoclast precursors, suggesting altered osteoclast differentiation. The reduction of osteoclast differentiation is associated with activation of Notch signaling. We conclude that Cx37 is required for osteoclast differentiation and fusion, and its absence leads to arrested osteoclast maturation and high bone mass in mice. These findings demonstrate a previously unrecognized role of Cx37 in bone homeostasis that is not compensated for by Cx43 in vivo.

  18. High Bone Mass in Mice Lacking Cx37 Because of Defective Osteoclast Differentiation*

    Science.gov (United States)

    Pacheco-Costa, Rafael; Hassan, Iraj; Reginato, Rejane D.; Davis, Hannah M.; Bruzzaniti, Angela; Allen, Matthew R.; Plotkin, Lilian I.

    2014-01-01

    Connexin (Cx) proteins are essential for cell differentiation, function, and survival in all tissues with Cx43 being the most studied in bone. We now report that Cx37, another member of the connexin family of proteins, is expressed in osteoclasts, osteoblasts, and osteocytes. Mice with global deletion of Cx37 (Cx37−/−) exhibit higher bone mineral density, cancellous bone volume, and mechanical strength compared with wild type littermates. Osteoclast number and surface are significantly lower in bone of Cx37−/− mice. In contrast, osteoblast number and surface and bone formation rate in bones from Cx37−/− mice are unchanged. Moreover, markers of osteoblast activity ex vivo and in vivo are similar to those of Cx37+/+ littermates. sRANKL/M-CSF treatment of nonadherent Cx37−/− bone marrow cells rendered a 5-fold lower level of osteoclast differentiation compared with Cx37+/+ cell cultures. Further, Cx37−/− osteoclasts are smaller and have fewer nuclei per cell. Expression of RANK, TRAP, cathepsin K, calcitonin receptor, matrix metalloproteinase 9, NFATc1, DC-STAMP, ATP6v0d1, and CD44, markers of osteoclast number, fusion, or activity, is lower in Cx37−/− osteoclasts compared with controls. In addition, nonadherent bone marrow cells from Cx37−/− mice exhibit higher levels of markers for osteoclast precursors, suggesting altered osteoclast differentiation. The reduction of osteoclast differentiation is associated with activation of Notch signaling. We conclude that Cx37 is required for osteoclast differentiation and fusion, and its absence leads to arrested osteoclast maturation and high bone mass in mice. These findings demonstrate a previously unrecognized role of Cx37 in bone homeostasis that is not compensated for by Cx43 in vivo. PMID:24509854

  19. Non-nuclear-initiated actions of the estrogen receptor protect cortical bone mass.

    Science.gov (United States)

    Bartell, Shoshana M; Han, Li; Kim, Ha-neui; Kim, Sung Hoon; Katzenellenbogen, John A; Katzenellenbogen, Benita S; Chambliss, Ken L; Shaul, Philip W; Roberson, Paula K; Weinstein, Robert S; Jilka, Robert L; Almeida, Maria; Manolagas, Stavros C

    2013-04-01

    Extensive evidence has suggested that at least some of the effects of estrogens on bone are mediated via extranuclear estrogen receptor α signaling. However, definitive proof for this contention and the extent to which such effects may contribute to the overall protective effects of estrogens on bone maintenance have remained elusive. Here, we investigated the ability of a 17β-estradiol (E2) dendrimer conjugate (EDC), incapable of stimulating nuclear-initiated actions of estrogen receptor α, to prevent the effects of ovariectomy (OVX) on the murine skeleton. We report that EDC was as potent as an equimolar dose of E2 in preventing bone loss in the cortical compartment that represents 80% of the entire skeleton, but was ineffective on cancellous bone. In contrast, E2 was effective in both compartments. Consistent with its effect on cortical bone mass, EDC partially prevented the loss of both vertebral and femoral strength. In addition, EDC, as did E2, prevented the OVX-induced increase in osteoclastogenesis, osteoblastogenesis, and oxidative stress. Nonetheless, the OVX-induced decrease in uterine weight was unaltered by EDC but was restored by E2. These results demonstrate that the protection of cortical bone mass by estrogens is mediated, at least in part, via a mechanism that is distinct from the classic mechanism of estrogen action on reproductive organs.

  20. The salutary effect of dietary calcium on bone mass in a rat model of simulated weightlessness

    Science.gov (United States)

    Bikle, D. D.; Globus, R.; Halloran, B. P.; Morey-Holton, E.

    1985-01-01

    Whether supplementation of dietary calcium reduces the differences in bone mass of unweighed limbs and normally weighted limbs, and whether parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D (1,25(OH)2D) respond differently to dietary calcium in unweighted animals in comparison with pair-fed controls was studied. The hind limbs of rats were unweighted by a tail suspension method and diets containing 0.1% to 2.4% calcium. After 2 weeks serum calcium, phosphorus, PTH and 1,25(OH)2D intestinal calcium transport were determined and bone mass, ash weight, and calcium in the tibia, L-1 vertebra, and humerus were measured. No significant differences in body weights were observed among the various groups. Suspended rats maintained constant levels of serum calcium and phosphate over the wide range of dietary calcium. Serum PTH and 1,25(OH)2D and intestinal calcium transport fell as dietary calcium was increased. Bone calcium in the tibia and vertebra from suspended rats remained less than that from pair-fed control. It is suggested that although no striking difference between suspended and control animals was observed in response to dieteary calcium, increasing dietary calcium may reduce the negative impact of unloading on the calcium content of the unweighted bones. The salutary effect of high dietary calcium appears to be due to inhibition of bone resorption rather than to stimulation of bone formation.

  1. Bone mass of female dance students prior to professional dance training: A cross-sectional study

    Science.gov (United States)

    Amorim, Tânia; Metsios, George S.; Wyon, Matthew; Nevill, Alan M.; Flouris, Andreas D.; Maia, José; Teixeira, Eduardo; Machado, José Carlos; Marques, Franklim; Koutedakis, Yiannis

    2017-01-01

    Background Professional dancers are at risk of developing low bone mineral density (BMD). However, whether low BMD phenotypes already exist in pre-vocational dance students is relatively unknown. Aim To cross-sectionally assess bone mass parameters in female dance students selected for professional dance training (first year vocational dance students) in relation to aged- and sex-matched controls. Methods 34 female selected for professional dance training (10.9yrs ±0.7) and 30 controls (11.1yrs ±0.5) were examined. Anthropometry, pubertal development (Tanner) and dietary data (3-day food diary) were recorded. BMD and bone mineral content (BMC) at forearm, femur neck (FN) and lumbar spine (LS) were assessed using Dual-Energy X-Ray Absorptiometry. Volumetric densities were estimated by calculating bone mineral apparent density (BMAD). Results Dancers were mainly at Tanner pubertal stage I (vs. stage IV in controls, pdance students continued to display a significantly lower BMD and BMAD at the FN (pdance training, first year vocational dance students demonstrated inferior bone mass compared to controls. Longitudinal models are required to assess how bone health-status changes with time throughout professional training. PMID:28678833

  2. Effects of COLIA1 polymorphisms and haplotypes on perimenopausal bone mass, postmenopausal bone loss and fracture risk

    DEFF Research Database (Denmark)

    González-Bofill, N; Husted, L B; Harsløf, T;

    2011-01-01

    : lumbar spine BMD 1.030 +/- 0.137 g/cm(2), 1.016 +/- 0.147 g/cm(2) and 0.988 +/- 0.124 g/cm(2) in women with the GG, GT and TT genotypes, respectively (p ..., respectively (p = 0.01). The effect remained after 10 years although statistical significance was lost. Haplotype 3 (-1997T-1663ins+1245G) was associated with lower bone mass and higher levels of bone turnover. Compared with haplotype 1, haplotype 3 carriers had lower BMD at the lumbar spine, femoral neck...... and total hip by 0.016 +/- 0.007 g/cm(2), 0.015 +/- 0.006 g/cm(2) and 0.017 +/- 0.006 g/cm(2), respectively (p risk and no overall interaction with the effects of hormone therapy could be demonstrated for any...

  3. [Modification of bone quality by extreme physical stress. Bone density measurements in high-performance athletes using dual-energy x-ray absorptiometry].

    Science.gov (United States)

    Sabo, D; Reiter, A; Pfeil, J; Güssbacher, A; Niethard, F U

    1996-01-01

    The treatment of osteoporosis is still controversial. Rehabilitation programs which stress strengthening exercises as well as impact loading activities increase the bone mass. On the other side activity level early in life has not been proven to correlate with increased bone mineral content later in life. Little is known on the influence of high performance sports on the bone density especially in athletes with high demands on weight bearing of the spine. In (n = 40) internationally top ranked high performance athletes of different disciplines (n = 28 weight-lifters, n = 6 sports-boxers and n = 6 bicycle-racers) bone density measurements of the lumbar spine and the left hip were performed. The measurements were carried out by dual-photonabsorptiometry (DEXA; QDR 2000, Siemens) and evaluated by an interactive software-programme (Hologic Inc.). The results were compared to the measurements of 21 age-matched male control individuals. In the high performance weight lifters there was an increase of bone density compared to the control individuals of 23% in the Ward's triangle (p boxers had an increase up to 17% (lumbar spine), 9% (hip) and 7% (Wards' triangle). In the third athletes group (Tour de France-bikers) BMD was decreased 10% in the lumbar spine, 14% in the hip and 17% in the Wards' triangle. Our results show that training programs stressing axial loads of the skeletal system may lead to an increase of BMD in the spine and the hip of young individuals. Other authors findings, that the BMD of endurance athletes may decrease, is confirmed. Nevertheless the bikers BMD-loss of 10 to 17% was surprisingly high.

  4. Bovine lactoferrin improves bone mass and microstructure in ovariectomized rats via OPG/RANKL/RANK pathway.

    Science.gov (United States)

    Hou, Jian-Ming; Xue, Ying; Lin, Qing-Ming

    2012-10-01

    Lactoferrin (LF), an 80-kDa iron-binding glycoprotein, is a pleiotropic factor found in colostrum, milk, saliva and epithelial cells of the exocrine glands. The aim of this study was to evaluate the effects of LF on the bones in ovariectomized (Ovx) rats and to identify the pathways that mediate the anabolic action of LF on the bones. Female Sprague-Dawley rats (6-month-old) underwent ovariectomy, and were treated with different doses of LF (10, 100, 1000, and 2000 mg·kg(-1)·d(-1), po) or with 7β-estradiol (0.1 mg·kg(-1), im, each week) as the positive control. By the end of 6 month-treatments, the bone mass and microstructure in the rats were scanned by micro-computed tomography (micro-CT), and the bone metabolism was evaluated with specific markers, and the mRNA levels of osteoprotegerin (OPG) and the receptor-activator of nuclear factor κB ligand (RANKL) in femur were measured using qRT-PCR. LF treatment dose-dependently elevated the bone volume (BV/TV), trabecular thickness (TbTh) and trabecular number (TbN), and reduced the trabecular separation (TbSp) in Ovx rats. Furthermore, higher doses of LF (1000 and 2000 mg·kg(-1)·d(-1)) significantly increased the bone mineral density (BMD) compared with the untreated Ovx rats. The higher doses of LF also significantly increased the serum levels of OC and BALP, and decreased the serum levels of β-CTx and NTX. LF treatment significantly increased the OPG mRNA levels, and suppressed the RANKL mRNA levels, and the RANKL/OPG mRNA ratio in Ovx rats. Oral administration of LF preserves the bone mass and improves the bone microarchitecture. LF enhances bone formation, reduces bone resorption, and decreases bone mass loss, possibly through the regulation of OPG/RANKL/RANK pathway.

  5. A NEW CLASS OF NASCENT ECLIPSING BINARIES WITH EXTREME MASS RATIOS

    Energy Technology Data Exchange (ETDEWEB)

    Moe, Maxwell; Stefano, Rosanne Di, E-mail: mmoe@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-10, Cambridge, MA 02138 (United States)

    2015-03-10

    Early B-type main-sequence (MS) stars (M {sub 1} ≈ 5-16 M {sub ☉}) with closely orbiting low-mass stellar companions (q = M {sub 2}/M {sub 1} < 0.25) can evolve to produce Type Ia supernovae, low-mass X-ray binaries, and millisecond pulsars. However, the formation mechanism and intrinsic frequency of such close extreme mass-ratio binaries have been debated, especially considering none have hitherto been detected. Utilizing observations of the Large Magellanic Cloud galaxy conducted by the Optical Gravitational Lensing Experiment, we have discovered a new class of eclipsing binaries in which a luminous B-type MS star irradiates a closely orbiting low-mass pre-MS companion that has not yet fully formed. The primordial pre-MS companions have large radii and discernibly reflect much of the light they intercept from the B-type MS primaries (ΔI {sub refl} ≈ 0.02-0.14 mag). For the 18 definitive MS + pre-MS eclipsing binaries in our sample with good model fits to the observed light-curves, we measure short orbital periods P = 3.0-8.5 days, young ages τ ≈ 0.6-8 Myr, and small secondary masses M {sub 2} ≈ 0.8-2.4 M {sub ☉} (q ≈ 0.07-0.36). The majority of these nascent eclipsing binaries are still associated with stellar nurseries, e.g., the system with the deepest eclipse ΔI {sub 1} = 2.8 mag and youngest age τ = 0.6 ± 0.4 Myr is embedded in the bright H II region 30 Doradus. After correcting for selection effects, we find that (2.0 ± 0.6)% of B-type MS stars have companions with short orbital periods P = 3.0-8.5 days and extreme mass ratios q ≈ 0.06-0.25. This is ≈10 times greater than that observed for solar-type MS primaries. We discuss how these new eclipsing binaries provide invaluable insights, diagnostics, and challenges for the formation and evolution of stars, binaries, and H II regions.

  6. Direct stimulation of bone mass by increased GH signalling in the osteoblasts of Socs2-/- mice.

    Science.gov (United States)

    Dobie, R; MacRae, V E; Huesa, C; van't Hof, R; Ahmed, S F; Farquharson, C

    2014-10-01

    The suppressor of cytokine signalling (Socs2(-/-))-knockout mouse is characterised by an overgrowth phenotype due to enhanced GH signalling. The objective of this study was to define the Socs2(-/-) bone phenotype and determine whether GH promotes bone mass via IGF1-dependent mechanisms. Despite no elevation in systemic IGF1 levels, increased body weight in 4-week-old Socs2(-/-) mice following GH treatment was associated with increased cortical bone area (Ct.Ar) (PGH. Indeed, male Socs2(-/-) mice had increased Ct.Ar (PGH action. Mechanistic studies showed that in osteoblasts and bone of Socs2(-/-) mice, STAT5 phosphorylation was significantly increased in response to GH. Conversely, overexpression of SOCS2 decreased GH-induced STAT5 signalling. Although an increase in Igf1 expression was observed in Socs2(-/-) osteoblasts following GH, it was not evident in vivo. Igf1 expression levels were not elevated in response to GH in 4-week-old mice and no alterations in expression was observed in bone samples of 6-week-old Socs2(-/-) mice. These studies emphasise the critical role of SOCS2 in controlling the local GH anabolic bone effects. We provide compelling evidence implicating SOCS2 in the regulation of GH osteoblast signalling and ultimately bone accrual, which maybe via mechanisms that are independent of IGF1 production in vivo.

  7. Bone Mass, Body Mass Index, and Lifestyle Factors: A Case Study of Walailak University Staff

    Directory of Open Access Journals (Sweden)

    Rapheeporn KHWANCHUEA

    2012-09-01

    Full Text Available To assess bone mineral density (BMD and explore lifestyle factors affecting BMD in 310 staff of Walailak University aged 25 - 45 years (men = 23.23 % and women 76.77 %. BMD was evaluated by Quantitative ultrasound (QUS analysis at the left distal-third radius. Anthropometric data including body mass index (BMI and waist circumferences (WC were measured, and lifestyle behaviors were also explored using the questionnaire. BMD status of both men and women showed similar results, 14.84 and 0.97 % of both genders were determined to have osteopenia and osteoporosis, respectively. Important data demonstrated the highest numbers of younger women aged 25 - 30 with osteopenia (30.61 %. Anthropometric results showed that 44.83 % of all subjects represented abnormal BMI (BMI < 18.5 and BMI  ³  23, and percentages of the men who had BMI more than 23 (51.39 % were larger than those of the women (30.67 %. In contrast, only 26.45 % of both genders demonstrated abnormal WC, and the numbers for women were higher. Descriptive data of beverage consumption showed that most of men and women subjects had caffeine and carbonated beverage intakes less than 7 cups per week (73.61 and 87.82 % and less than 3 cups per week (95.83 and 97.06 % respectively, whereas only 9.72 and 26.89 % of men and women consumed more than 3 packs of milk per week. Results of lifestyle behaviors showed that almost all subjects preferred exercise, but only 47.22 and 31.09 % of men and women exercises 3 or more times per week. The multivariate analysis showed that BMD status is significantly associated with age group and BMI (OR = 3.30, CI, 1.086 – 6.3747 and OR = 0.43, CI, 0.2697 – 0.9805, respectively after adjusting for age and gender. Normal BMI and older age group are the potential determinants, and other risk factors such as caffeine and carbonated beverages are sufficient concerns in adults.

  8. Adolescence: How do we increase intestinal calcium absorption to allow for bone mineral mass accumulation?

    Science.gov (United States)

    An increase in calcium absorptive efficiency (fractional absorption of dietary calcium) during adolescence is associated with a rapid increase in total body bone mineral mass (BMM) accumulation. This increase occurs across a range of calcium intakes. It appears to be principally mediated by hormonal...

  9. Chronic obstructive pulmonary disease and low bone mass: A case-control study

    Directory of Open Access Journals (Sweden)

    Rakesh K Gupta

    2014-01-01

    Full Text Available Background and Objective: Low bone mass (osteopenia and osteoporosis is one of the effects associated with chronic obstructive pulmonary disease (COPD. There is very little data from Saudi Arabia on COPD and low bone mass. This retrospective study was done to assess the prevalence of osteoporosis and osteopenia in COPD patients attending King Fahd Hospital of the University (KFHU, Alkhobar. Patients and Methods: After obtaining the ethical approval from the research committee, all patients seen between at the King Fahd Hospital of the University between January 2010 and December 2012 were included. The inclusion criteria included a follow up of a minimum 2 years, and the Medical Records should have the details of forced expiratory volume in one second (FEV 1 , blood bone profile and bone biomarkers and dual-energy X-ray absorptiometry (DEXA scan. Patients were labeled as osteopenia if the T score was -<1 to <-2.5 and osteoporosis of <-2.5 as per the WHO definition of osteopenia and osteoporosis. Results: Seventy-three patients were being followed in the clinics and 49 patients satisfied the inclusion criteria. The average age was 60.6 ± 10.47 years; males were 43 and females 6. Three (6.1% were normal and the remaining 46 (93.9% were with low bone mass. Thirty-two (65.3% were osteoporotic and 14 (28.57% were osteopenic. The average duration of COPD was 4.5 ± 6.2 years. Majority (n = 36, 73.4% of patients were in the Global Initiative for COPD (GOLD class II and III. FEV 1 was significantly lower in the patients with low bone mass 1.66 ± 0.60 versus 3.61 ± 0.58 (P < 0.001. Conclusions: Our study shows that over 90% of Saudi Arabian patients with COPD suffer from osteopenia and osteoporosis and unfortunately they remain under-diagnosed and undertreated.

  10. Bone mass and microarchitecture in CKD patients with fracture.

    Science.gov (United States)

    Nickolas, Thomas L; Stein, Emily; Cohen, Adi; Thomas, Valerie; Staron, Ronald B; McMahon, Donald J; Leonard, Mary B; Shane, Elizabeth

    2010-08-01

    Patients with predialysis chronic kidney disease (CKD) have increased risk for fracture, but the structural mechanisms underlying this increased skeletal fragility are unknown. We measured areal bone mineral density (aBMD) by dual-energy x-ray absorptiometry at the spine, hip, and radius, and we measured volumetric BMD (vBMD), geometry, and microarchitecture by high-resolution peripheral quantitative computed tomography (HR-pQCT) at the radius and tibia in patients with CKD: 32 with fracture and 59 without fracture. Patients with fracture had lower aBMD at the spine, total hip, femoral neck, and the ultradistal radius, the last having the strongest association with fracture. By HR-pQCT of the radius, patients with fracture had lower cortical area and thickness, total and trabecular vBMD, and trabecular number and greater trabecular separation and network heterogeneity. At the tibia, patients with fracture had significantly lower cortical area, thickness, and total and cortical density. Total vBMD at both radius and tibia most strongly associated with fracture. By receiver operator characteristic curve analysis, patients with longer duration of CKD had area under the curve of >0.75 for aBMD at both hip sites and the ultradistal radius, vBMD and geometry at the radius and tibia, and microarchitecture at the tibia. In summary, patients with predialysis CKD and fractures have lower aBMD by dual-energy x-ray absorptiometry and lower vBMD, thinner cortices, and trabecular loss by HR-pQCT. These density and structural differences may underlie the increased susceptibility to fracture among patients with CKD.

  11. Leo P: A very low-mass, extremely metal-poor, star-forming galaxy

    Science.gov (United States)

    McQuinn, Kristen B.; Leo P Team

    2017-01-01

    Leo P is a low-luminosity dwarf galaxy just outside the Local Group with properties that make it an ideal probe of galaxy evolution at the faint-end of the luminosity function. Using combined data from 2 Hubble Space Telescope (HST) observing campaigns, the Very Large Array, the Spitzer Space telescope, as well as ground based data, we have constructed a robust evolutionary picture of Leo P. Leo P is one the most metal-poor, gas-rich galaxies ever discovered, has a stellar mass of a 5x105 Msun, comparable gas mass, and a single HII region. The star formation history reconstructed from the resolved stellar populations in Leo P shows it is unquenched, despite its very low mass. Based on the star formation history and metallicity measurements, the galaxy has lost 95% of its oxygen produced via nucleosynthesis, presumably to outflows. The neutral gas in the galaxy shows signs of rotation, although the velocity dispersion is comparable to the rotation velocity. Thus, Leo P bridges the gap between more massive dwarf irregular and less massive dwarf spheroidals on the baryonic Tully-Fisher relation. Furthermore, the galaxy hosts several, extremely dusty AGB candidates which will be probed with new HST and Spitzer observations. If confirmed as AGB stars, these may be our best local proxies for studying chemically unevolved star formation and subsequent dust production in metallicity environments comparable to the early universe.

  12. Persistent junk solutions in time-domain modeling of extreme mass ratio binaries

    CERN Document Server

    Field, Scott E; Lau, Stephen R

    2010-01-01

    In the context of metric perturbation theory for non-spinning black holes, extreme mass ratio binary (EMRB) systems are described by distributionally forced master wave equations. Numerical solution of a master wave equation as an initial boundary value problem requires initial data. However, because the correct initial data for generic-orbit systems is unknown, specification of trivial initial data is a common choice, despite being inconsistent and resulting in a solution which is initially discontinuous in time. As is well known, this choice leads to a "burst" of junk radiation which eventually propagates off the computational domain. We observe another unintended consequence of trivial initial data: development of a persistent spurious solution, here referred to as the Jost junk solution, which contaminates the physical solution for long times. This work studies the influence of both types of junk on metric perturbations, waveforms, and self-force measurements, and it demonstrates that smooth modified sour...

  13. From symmetric cold fission fragment mass distributions to extremely asymmetric alpha decay

    Science.gov (United States)

    Poenaru, D. N.; Ivascu, M.; Maruhn*, J. A.; Greiner*, W.

    1987-12-01

    The analytical superasymmetric fission model, successful in the study of extremely asymmetric decay modes like α-decay and heavy ion radioactivities, is applied to cold fission phenomena. The three groups of processes are described in a unifield manner, showing that cold fission could be considered heavy cluster emission. For 234U all groups have been detected. The highest symmetry of the gragment mass distributions should be observed for the neutron rich nucleus 264Fm, leading to doubly magic products 132Sn. The most probable light fragments from cold fission of 234,236U, 239Np and 240Pu are 100Zr, 104,106,108Mo respectively, in good agreement with experimental data.

  14. From symmetric cold fission fragment mass distributions to extremely asymmetric alpha decay

    Energy Technology Data Exchange (ETDEWEB)

    Poenaru, D.N.; Ivascu, M.; Maruhn, J.A.; Greiner, W.

    1987-12-10

    The analytical superasymmetric fission model, successful in the study of extremely asymmetric decay modes like ..cap alpha..-decay and heavy ion radioactivities, is applied to cold fission phenomena. The three groups of processes are described in a unifield manner, showing that cold fission could be considered heavy cluster emission. For /sup 234/U all groups have been detected. The highest symmetry of the gragment mass distributions should be observed for the neutron rich nucleus /sup 264/Fm, leading to doubly magic products /sup 132/Sn. The most probable light fragments from cold fission of /sup 234,236/U, /sup 239/Np and /sup 240/Pu are /sup 100/Zr, /sup 104,106,108/Mo respectively, in good agreement with experimental data.

  15. Tracing molecular gas mass in extreme extragalactic environments: an observational study

    CERN Document Server

    Zhu, Ming; Xilouris, Emmanuel M; Kuno, Nario; Lisenfeld, Ute

    2009-01-01

    We present a new observational study of the CO(1-0) line emission as an H2 gas mass tracer under extreme conditions in extragalactic environments. Our approach is to study the full neutral interstellar medium (H2, HI and dust) of two galaxies whose bulk interstellar medium (ISM) resides in environments that mark (and bracket) the excitation extremes of the ISM conditions found in infrared luminous galaxies, the starburst NGC3310 and the quiescent spiral NGC157. Our study maintains a robust statistical notion of the so-called X factor (i.e. a large ensemble of clouds is involved) while exploring its dependency on the very different average ISM conditions prevailing within these two systems. These are constrained by fully-sampled CO(3-2) and CO(1-0) observations, at a matched beam resolution of Half Power Beam Width 15'', obtained with the JCMT the Nobeyama 45-m telescope, combined with sensitive 850 and 450 micron dust emission and HI interferometric images which allow a complete view of all the neutral ISM co...

  16. Soccer increases bone mass in prepubescent boys during growth: a 3-yr longitudinal study.

    Science.gov (United States)

    Zouch, Mohamed; Zribi, Anis; Alexandre, Christian; Chaari, Hamada; Frere, Delphine; Tabka, Zouhair; Vico, Laurence

    2015-01-01

    The aim of this study was to examine the effect of 3-yr soccer practice on bone acquisition in prepubescent boys. We investigated 65 boys (aged 10-13 yr, Tanner stage I) at baseline, among which only 40 boys (Tanner stages II and III) have continued the 3-yr follow-up: 23 soccer players (F) completed 2-5 h of training plus 1 competition game per week and 17 controls (C). Bone mineral density (BMD, g/cm(2)) and bone mineral content (BMC, g) were measured by dual-energy X-ray absorptiometry at different sites. At baseline, BMD was higher in soccer players than in controls in the whole body and legs. In contrast, there was nonsignificant difference BMD in head, femoral neck, arms, and BMC in all measured sites between groups. At 3-yr follow-up, soccer players were found to have higher BMD and BMC at all sites than controls, except for head BMD and BMC and arms BMC in which the difference was nonsignificant between groups. During the 3-yr follow-up, the soccer players were found to gain significantly more in lumbar spine (31.2% ± 2.9% vs 23.9% ± 2.1%; p bone mass induced by soccer training in the stressed sites was associated to a decreased skull bone mass after 3 yr of follow-up. Copyright © 2015 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  17. Conditional abrogation of Atm in osteoclasts extends osteoclast lifespan and results in reduced bone mass.

    Science.gov (United States)

    Hirozane, Toru; Tohmonda, Takahide; Yoda, Masaki; Shimoda, Masayuki; Kanai, Yae; Matsumoto, Morio; Morioka, Hideo; Nakamura, Masaya; Horiuchi, Keisuke

    2016-09-28

    Ataxia-telangiectasia mutated (ATM) kinase is a central component involved in the signal transduction of the DNA damage response (DDR) and thus plays a critical role in the maintenance of genomic integrity. Although the primary functions of ATM are associated with the DDR, emerging data suggest that ATM has many additional roles that are not directly related to the DDR, including the regulation of oxidative stress signaling, insulin sensitivity, mitochondrial homeostasis, and lymphocyte development. Patients and mice lacking ATM exhibit growth retardation and lower bone mass; however, the mechanisms underlying the skeletal defects are not fully understood. In the present study, we generated mutant mice in which ATM is specifically inactivated in osteoclasts. The mutant mice did not exhibit apparent developmental defects but showed reduced bone mass due to increased osteoclastic bone resorption. Osteoclasts lacking ATM were more resistant to apoptosis and showed a prolonged lifespan compared to the controls. Notably, the inactivation of ATM in osteoclasts resulted in enhanced NF-κB signaling and an increase in the expression of NF-κB-targeted genes. The present study reveals a novel function for ATM in regulating bone metabolism by suppressing the lifespan of osteoclasts and osteoclast-mediated bone resorption.

  18. Prostaglandin E2 Increased Rat Cortical Bone Mass When Administered Immediately Following Ovariectomy

    Science.gov (United States)

    Ke, Hua Zhu; Jee, Webster S.S.; Zeng, Qing Qiang; Li, Mei; Lin, Bai Yun

    1993-01-01

    cavity to increase total bone mass in the tibial shaft of OVX rats when given immediately following ovafiectomy.

  19. Losartan increases bone mass and accelerates chondrocyte hypertrophy in developing skeleton.

    Science.gov (United States)

    Chen, Shan; Grover, Monica; Sibai, Tarek; Black, Jennifer; Rianon, Nahid; Rajagopal, Abbhirami; Munivez, Elda; Bertin, Terry; Dawson, Brian; Chen, Yuqing; Jiang, Ming-Ming; Lee, Brendan; Yang, Tao; Bae, Yangjin

    2015-05-01

    Angiotensin receptor blockers (ARBs) are a group of anti-hypertensive drugs that are widely used to treat pediatric hypertension. Recent application of ARBs to treat diseases such as Marfan syndrome or Alport syndrome has shown positive outcomes in animal and human studies, suggesting a broader therapeutic potential for this class of drugs. Multiple studies have reported a benefit of ARBs on adult bone homeostasis; however, its effect on the growing skeleton in children is unknown. We investigated the effect of Losartan, an ARB, in regulating bone mass and cartilage during development in mice. Wild type mice were treated with Losartan from birth until 6 weeks of age, after which bones were collected for microCT and histomorphometric analyses. Losartan increased trabecular bone volume vs. tissue volume (a 98% increase) and cortical thickness (a 9% increase) in 6-weeks old wild type mice. The bone changes were attributed to decreased osteoclastogenesis as demonstrated by reduced osteoclast number per bone surface in vivo and suppressed osteoclast differentiation in vitro. At the molecular level, Angiotensin II-induced ERK1/2 phosphorylation in RAW cells was attenuated by Losartan. Similarly, RANKL-induced ERK1/2 phosphorylation was suppressed by Losartan, suggesting a convergence of RANKL and angiotensin signaling at the level of ERK1/2 regulation. To assess the effect of Losartan on cartilage development, we examined the cartilage phenotype of wild type mice treated with Losartan in utero from conception to 1 day of age. Growth plates of these mice showed an elongated hypertrophic chondrocyte zone and increased Col10a1 expression level, with minimal changes in chondrocyte proliferation. Altogether, inhibition of the angiotensin pathway by Losartan increases bone mass and accelerates chondrocyte hypertrophy in growth plate during skeletal development.

  20. Disease-modifying antirheumatic drugs and bone mass in rheumatoid arthritis.

    Science.gov (United States)

    Di Munno, O; Delle Sedie, A; Rossini, M; Adami, S

    2005-01-01

    This article reviews the effects of DMARDs (including biologic agents) on bone metabolism in rheumatoid arthritis (RA). At present there is no evidence that methotrexate, at least at dosages ranging from 5 to 20 mg/week, negatively affects bone mass as measured by DXA (BMD) as documented in both cross-sectional and longitudinal studies. Most studies of cyclosporine (CyA) use reporting a reduction in erosions and joint damage with no adverse effects on bone, did not measure BMD; CyA treatment is associated with a dose-dependent increase of bone turnover as well as a decrease in both animal and human studies; however, its use in RA setting at a dose < or =5 mg/Kg/ day has so far not been associated with clinical relevant adverse effects on bone metabolism. Anti-TNF-alpha agents, infliximab reduced markers of bone turnover in two longitudinal studies. Data on BMD are not available in RA; nevertheless, an increase in BMD has been documented in spondyloarthropathies with infliximab and etanercept. No clinical data concerning BMD are available on leflunomide as well as on the newer biologic agents (adalimumab, rituximab, anakinra).

  1. Handball Practice Enhances Bone Mass in Specific Sites Among Prepubescent Boys.

    Science.gov (United States)

    Missawi, Kawther; Zouch, Mohamed; Chakroun, Yosra; Chaari, Hamada; Tabka, Zouhair; Bouajina, Elyès

    2016-01-01

    This investigation's purpose is to focus on the effects of practicing handball for at least 2 yr on bone acquisition among prepubescent boys. One hundred prepubescent boys aged 10.68 ± 0.85 yr were divided into 2 groups: 50 handball players (HP group) and 50 controls (C group). Bone mineral density (BMD), bone mineral content (BMC), and bone area (BA) were evaluated by using dual-photon X-ray absorptiometry on the whole body, lumbar spine (L2-L4), legs, arms, femoral necks, hips and radiuses. Results showed greater values of BMD in both right and left femoral neck and total hip in handball players than in controls. In addition, handball players had higher values of legs and right total hip BMC than controls without any obvious variation of BA measurement in all sites between groups. All results of the paired t-test displayed an obviously marked variation of bone mass parameters between the left and right sides in the trained group without any marked variation among controls. Data showed an increased BMD of the supporting sites between the left and the right leg among handball players. However, "BMC" results exhibited higher values in the right than in the left total hip, and in the right total radius than in the left correspondent site. In addition, differences in the "BA" measurements were observed in the left total hip and in the right arm. Specific bone sites are markedly stimulated by handball training in prepubescent boys.

  2. Trabecular bone mineral density measured by quantitative CT of the lumbar spine in children and adolescents: reference values and peak bone mass; Trabekulaere Knochendichte der Lendenwirbelsaeule bei Kindern und Jugendlichen in der quantitativen CT: Referenzwerte und Peak Bone Mass

    Energy Technology Data Exchange (ETDEWEB)

    Berthold, L.D.; Alzen, G. [Kinderradiologie, Zentrum fuer Radiologie, Universitaetsklinikum Giessen und Marburg GmbH, Standort Giessen (Germany); Haras, G. [Siemens AG, Medical Solutions, Forchheim (Germany); Mann, M. [AG Medizinische Statistik, Universitaetsklinikum Giessen und Marburg GmbH, Standort Giessen (Germany)

    2006-12-15

    Purpose: The aim of this study was to assess bone density values in the trabecular substance of the lumbar vertebral column in children and young adults in Germany from infancy to the age of peak bone mass. Materials and Methods: We performed quantiative computed tomography (QCT) on the first lumbar vertebra in 28 children and adolescents without diseases that may influence bone metabolism (15 boys, 13 girls, mean ages 11 and 8 years, respectively). We also measured 17 healthy young adults (9 men, 8 women, mean ages 20 and 21 years). We used a Somatom Balance Scanner (Siemens, Erlangen) and the Siemens Osteo software. Scan parameters: Slice thickness 1 cm, 80 kV, 81 or 114 mAs. We measured the trabecular bone density and the area and height of the vertebra and calculated the volume and content of calcium hydroxyapatite (Ca-HA) in the trabecular substance of the first lumbar vertebra. Results: Prepubertal boys had a mean bone density of 148.5 (median [med] 150.1, standard deviation [SD] 15.4) mg/Ca-HA per ml bone, and prepubertal girls had a mean density of 149.5 (med 150.8, SD 23.5) mg/ml. We did not observe a difference between prepubertal boys and girls. After puberty there was a significant difference (p<0.001) between males and females: Mean density (male) 158.0, med 162.5, SD 24.0 mg/ml, mean density (female) 191.2, med 191.3, SD 17.7 mg/ml. The Ca-HA content in the trabecular bone of the first lumbar vertebra was 1.1 (med 1.1, SD 0.5) g for prepubertal boys and 1.1 (0.9, 0.4) g for prepubertal girls. For post-pubertal males, the mean Ca-HA content was 3.5 g, med 3.5 SD 0.5 g, and for post-pubertal females, the mean content was 2.8, med 2.7, SD 0.4 g. Conclusion: The normal trabecular bone mineral density is 150 mg/ml with a standard deviation of 20 mg/ml independent of age or gender until the beginning of puberty. Peak bone mass (bone mineral content) in the trabecular substance of the lumbar vertebral column is higher in males than in females, and peak bone

  3. Vitamin B12–dependent taurine synthesis regulates growth and bone mass

    Science.gov (United States)

    Roman-Garcia, Pablo; Quiros-Gonzalez, Isabel; Mottram, Lynda; Lieben, Liesbet; Sharan, Kunal; Wangwiwatsin, Arporn; Tubio, Jose; Lewis, Kirsty; Wilkinson, Debbie; Santhanam, Balaji; Sarper, Nazan; Clare, Simon; Vassiliou, George S.; Velagapudi, Vidya R.; Dougan, Gordon; Yadav, Vijay K.

    2014-01-01

    Both maternal and offspring-derived factors contribute to lifelong growth and bone mass accrual, although the specific role of maternal deficiencies in the growth and bone mass of offspring is poorly understood. In the present study, we have shown that vitamin B12 (B12) deficiency in a murine genetic model results in severe postweaning growth retardation and osteoporosis, and the severity and time of onset of this phenotype in the offspring depends on the maternal genotype. Using integrated physiological and metabolomic analysis, we determined that B12 deficiency in the offspring decreases liver taurine production and associates with abrogation of a growth hormone/insulin-like growth factor 1 (GH/IGF1) axis. Taurine increased GH-dependent IGF1 synthesis in the liver, which subsequently enhanced osteoblast function, and in B12-deficient offspring, oral administration of taurine rescued their growth retardation and osteoporosis phenotypes. These results identify B12 as an essential vitamin that positively regulates postweaning growth and bone formation through taurine synthesis and suggests potential therapies to increase bone mass. PMID:24911144

  4. Vitamin B₁₂-dependent taurine synthesis regulates growth and bone mass.

    Science.gov (United States)

    Roman-Garcia, Pablo; Quiros-Gonzalez, Isabel; Mottram, Lynda; Lieben, Liesbet; Sharan, Kunal; Wangwiwatsin, Arporn; Tubio, Jose; Lewis, Kirsty; Wilkinson, Debbie; Santhanam, Balaji; Sarper, Nazan; Clare, Simon; Vassiliou, George S; Velagapudi, Vidya R; Dougan, Gordon; Yadav, Vijay K

    2014-07-01

    Both maternal and offspring-derived factors contribute to lifelong growth and bone mass accrual, although the specific role of maternal deficiencies in the growth and bone mass of offspring is poorly understood. In the present study, we have shown that vitamin B12 (B12) deficiency in a murine genetic model results in severe postweaning growth retardation and osteoporosis, and the severity and time of onset of this phenotype in the offspring depends on the maternal genotype. Using integrated physiological and metabolomic analysis, we determined that B12 deficiency in the offspring decreases liver taurine production and associates with abrogation of a growth hormone/insulin-like growth factor 1 (GH/IGF1) axis. Taurine increased GH-dependent IGF1 synthesis in the liver, which subsequently enhanced osteoblast function, and in B12-deficient offspring, oral administration of taurine rescued their growth retardation and osteoporosis phenotypes. These results identify B12 as an essential vitamin that positively regulates postweaning growth and bone formation through taurine synthesis and suggests potential therapies to increase bone mass.

  5. The Relationship of Fat Distribution and Insulin Resistance with Lumbar Spine Bone Mass in Women.

    Directory of Open Access Journals (Sweden)

    Francisco J A de Paula

    Full Text Available Bone marrow harbors a significant amount of body adipose tissue (BMAT. While BMAT might be a source of energy for bone modeling and remodeling, its increment can also represent impairment of osteoblast differentiation. The relationship between BMAT, bone mass and insulin sensitivity is only partially understood and seems to depend on the circumstances. The present study was designed to assess the association of BMAT with bone mineral density in the lumbar spine as well as with visceral adipose tissue, intrahepatic lipids, HOMA-IR, and serum levels of insulin and glucose. This cross-sectional clinical investigation included 31 non-diabetic women, but 11 had a pre-diabetes status. Dual X-ray energy absorptiometry was used to measure bone mineral density and magnetic resonance imaging was used to assess fat deposition in BMAT, visceral adipose tissue and liver. Our results suggest that in non-diabetic, there is an inverse relationship between bone mineral density in lumbar spine and BMAT and a trend persists after adjustment for weight, age, BMI and height. While there is a positive association between visceral adipose tissue and intrahepatic lipids with serum insulin levels, there is no association between BMAT and serum levels of insulin. Conversely, a positive relationship was observed between BMAT and serum glucose levels, whereas this association was not observed with other fat deposits. These relationships did not apply after adjustment for body weight, BMI, height and age. The present study shows that in a group of predominantly non-obese women the association between insulin resistance and BMAT is not an early event, as occurs with visceral adipose tissue and intrahepatic lipids. On the other hand, BMAT has a negative relationship with bone mineral density. Taken together, the results support the view that bone has a complex and non-linear relationship with energy metabolism.

  6. Deficiency of retinaldehyde dehydrogenase 1 induces BMP2 and increases bone mass in vivo.

    Directory of Open Access Journals (Sweden)

    Shriram Nallamshetty

    Full Text Available The effects of retinoids, the structural derivatives of vitamin A (retinol, on post-natal peak bone density acquisition and skeletal remodeling are complex and compartment specific. Emerging data indicates that retinoids, such as all trans retinoic acid (ATRA and its precursor all trans retinaldehyde (Rald, exhibit distinct and divergent transcriptional effects in metabolism. Despite these observations, the role of enzymes that control retinoid metabolism in bone remains undefined. In this study, we examined the skeletal phenotype of mice deficient in retinaldehyde dehydrogenase 1 (Aldh1a1, the enzyme responsible for converting Rald to ATRA in adult animals. Bone densitometry and micro-computed tomography (µCT demonstrated that Aldh1a1-deficient (Aldh1a1(-/- female mice had higher trabecular and cortical bone mass compared to age and sex-matched control C57Bl/6 wild type (WT mice at multiple time points. Histomorphometry confirmed increased cortical bone thickness and demonstrated significantly higher bone marrow adiposity in Aldh1a1(-/- mice. In serum assays, Aldh1a1(-/- mice also had higher serum IGF-1 levels. In vitro, primary Aldh1a1(-/- mesenchymal stem cells (MSCs expressed significantly higher levels of bone morphogenetic protein 2 (BMP2 and demonstrated enhanced osteoblastogenesis and adipogenesis versus WT MSCs. BMP2 was also expressed at higher levels in the femurs and tibias of Aldh1a1(-/- mice with accompanying induction of BMP2-regulated responses, including expression of Runx2 and alkaline phosphatase, and Smad phosphorylation. In vitro, Rald, which accumulates in Aldh1a1(-/- mice, potently induced BMP2 in WT MSCs in a retinoic acid receptor (RAR-dependent manner, suggesting that Rald is involved in the BMP2 increases seen in Aldh1a1 deficiency in vivo. Collectively, these data implicate Aldh1a1 as a novel determinant of cortical bone density and marrow adiposity in the skeleton in vivo through modulation of BMP signaling.

  7. The Relationship of Fat Distribution and Insulin Resistance with Lumbar Spine Bone Mass in Women.

    Science.gov (United States)

    de Paula, Francisco J A; de Araújo, Iana M; Carvalho, Adriana L; Elias, Jorge; Salmon, Carlos E G; Nogueira-Barbosa, Marcello H

    2015-01-01

    Bone marrow harbors a significant amount of body adipose tissue (BMAT). While BMAT might be a source of energy for bone modeling and remodeling, its increment can also represent impairment of osteoblast differentiation. The relationship between BMAT, bone mass and insulin sensitivity is only partially understood and seems to depend on the circumstances. The present study was designed to assess the association of BMAT with bone mineral density in the lumbar spine as well as with visceral adipose tissue, intrahepatic lipids, HOMA-IR, and serum levels of insulin and glucose. This cross-sectional clinical investigation included 31 non-diabetic women, but 11 had a pre-diabetes status. Dual X-ray energy absorptiometry was used to measure bone mineral density and magnetic resonance imaging was used to assess fat deposition in BMAT, visceral adipose tissue and liver. Our results suggest that in non-diabetic, there is an inverse relationship between bone mineral density in lumbar spine and BMAT and a trend persists after adjustment for weight, age, BMI and height. While there is a positive association between visceral adipose tissue and intrahepatic lipids with serum insulin levels, there is no association between BMAT and serum levels of insulin. Conversely, a positive relationship was observed between BMAT and serum glucose levels, whereas this association was not observed with other fat deposits. These relationships did not apply after adjustment for body weight, BMI, height and age. The present study shows that in a group of predominantly non-obese women the association between insulin resistance and BMAT is not an early event, as occurs with visceral adipose tissue and intrahepatic lipids. On the other hand, BMAT has a negative relationship with bone mineral density. Taken together, the results support the view that bone has a complex and non-linear relationship with energy metabolism.

  8. Appendicular bone mass and knee and hand osteoarthritis in Japanese women: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Moji Kazuhiko

    2002-10-01

    Full Text Available Abstract Background It has been reported that there is an inverse association between osteoarthritis (OA and osteoporosis. However, the relationship of bone mass to OA in a Japanese population whose rates of OA are different from Caucasians remains uncertain. Methods We studied the association of appendicular bone mineral density (second metacarpal; mBMD and quantitative bone ultrasound (calcaneus; stiffness index with knee and hand OA among 567 Japanese community-dwelling women. Knee and hand radiographs were scored for OA using Kellgren-Lawrence (K/L scales. In addition, we evaluated the presence of osteophytes and of joint space narrowing. The hand joints were examined at the distal and proximal interphalangeal (DIP, PIP and first metacarpophalangeal/carpometacarpal (MCP/CMC joints. Results After adjusting for age and body mass index (BMI, stiffness index was significantly higher in women with K/L scale, grade 3 at CMC/MCP joint compared with those with no OA. Adjusted means of stiffness index and mBMD were significantly higher in women with definite osteophytes at the CMC/MCP joint compared to those without osteophytes, whereas there were no significant differences for knee, DIP and PIP joints. Stiffness index, but not mBMD, was higher in women with definite joint space narrowing at the CMC/MCP joint compared with those with no joint space narrowing. Conclusions Appendicular bone mass was increased with OA at the CMC/MCP joint, especially among women with osteophytes. Our findings suggest that the association of peripheral bone mass with OA for knee, DIP or PIP may be less clearcut in Japanese women than in other populations.

  9. Establishment of age- and sex-adjusted reference data for hand bone mass and investigation of hand bone loss in patients with rheumatoid arthritis treated in clinical practice

    DEFF Research Database (Denmark)

    Ørnbjerg, Lykke Midtbøll; Østergaard, Mikkel; Jensen, Trine

    2016-01-01

    BACKGROUND: Rheumatoid arthritis is characterised by progressive joint destruction and loss of periarticular bone mass. Hand bone loss (HBL) has therefore been proposed as an outcome measure for treatment efficacy. A definition of increased HBL adjusted for age- and sex-related bone loss is lacking....... In this study, we aimed to: 1) establish reference values for normal hand bone mass (bone mineral density measured by digital x-ray radiogrammetry (DXR-BMD)); and 2) examine whether HBL is normalised in rheumatoid arthritis patients during treatment with tumour necrosis factor alpha inhibitors (TNFI). METHODS......: DXR-BMD was measured from hand x-rays in a reference cohort (1485 men/2541 women) without arthritis randomly selected from an urban Danish population. Sex- and age-related HBL/year was estimated. DXR-BMD was measured in rheumatoid arthritis patients (n = 350: at start of TNFI, and ~2 years after TNFI...

  10. Very Low-Mass Stars with Extremely Low Metallicity in the Milky Way's Halo

    Science.gov (United States)

    Aoki, Wako; Beers, Timothy C.; Suda, Takuma; Honda, Satoshi; Lee, Young Sun

    2016-08-01

    Large surveys and follow-up spectroscopic studies in the past few decades have been providing chemical abundance data for a growing number of very metal-poor ([Fe/H] LTE model atmospheres has obtained self-consistent chemical abundances for these objects, assuming small values of micro-turbulent velocities compared with giants and turn-off stars. The low temperature of the atmospheres of these objects enables us to measure their detailed chemical abundances. Interestingly, two of the four stars have extreme chemical-abundance patterns: one has the largest excesses of heavy neutron-capture elements associated with the r-process abundance pattern known to date (Aoki et al. 2010), and the other exhibits low abundances of the α-elements and odd-Z elements, suggested to be signatures of the yields of very massive stars (> 100 solar masses; Aoki et al. 2014). Although the sample size is still small, these results indicate the potential of very low-mass stars as probes to study the early stages of the Milky Way's halo formation.

  11. Discovery of a Bright, Extremely Low-Mass White Dwarf in a Close Double Degenerate System

    CERN Document Server

    Vennes, S; Kawka, A; Nemeth, P; Skinner, J N; Pigulski, A; Steslicki, M; Kolaczkowski, Z; Srodka, P; 10.1088/2041-8205/737/1/L16

    2011-01-01

    We report the discovery of a bright (V ~ 13.7), extremely low-mass white dwarf in a close double degenerate system. We originally selected GALEX J171708.5+675712 for spectroscopic follow-up among a group of white dwarf candidates in an ultraviolet-optical reduced proper-motion diagram. The new white dwarf has a mass of 0.18 M_solar and is the primary component of a close double degenerate system (P=0.246137 d, K_1 = 288 km/s) comprising a fainter white dwarf secondary with M_2 ~ 0.9 M_solar. Light curves phased with the orbital ephemeris show evidence of relativistic beaming and weaker ellipsoidal variations. The light curves also reveal secondary eclipses (depth ~ 8 mmag) while the primary eclipses appear partially compensated by the secondary gravitational deflection and are below detection limits. Photospheric abundance measurements show a nearly solar composition of Si, Ca, and Fe (0.1-1 solar), while the normal kinematics suggest a relatively recent formation history. Close binary evolutionary scenarios ...

  12. Generalised extreme value distributions provide a natural hypothesis for the shape of seed mass distributions.

    Directory of Open Access Journals (Sweden)

    Will Edwards

    Full Text Available Among co-occurring species, values for functionally important plant traits span orders of magnitude, are uni-modal, and generally positively skewed. Such data are usually log-transformed "for normality" but no convincing mechanistic explanation for a log-normal expectation exists. Here we propose a hypothesis for the distribution of seed masses based on generalised extreme value distributions (GEVs, a class of probability distributions used in climatology to characterise the impact of event magnitudes and frequencies; events that impose strong directional selection on biological traits. In tests involving datasets from 34 locations across the globe, GEVs described log10 seed mass distributions as well or better than conventional normalising statistics in 79% of cases, and revealed a systematic tendency for an overabundance of small seed sizes associated with low latitudes. GEVs characterise disturbance events experienced in a location to which individual species' life histories could respond, providing a natural, biological explanation for trait expression that is lacking from all previous hypotheses attempting to describe trait distributions in multispecies assemblages. We suggest that GEVs could provide a mechanistic explanation for plant trait distributions and potentially link biology and climatology under a single paradigm.

  13. Kefir improves bone mass and microarchitecture in an ovariectomized rat model of postmenopausal osteoporosis.

    Science.gov (United States)

    Chen, H-L; Tung, Y-T; Chuang, C-H; Tu, M-Y; Tsai, T-C; Chang, S-Y; Chen, C-M

    2015-02-01

    Kefir treatment in ovariectomized (OVX) rats could significantly decrease the levels of bone turnover markers and prevent OVX-induced bone loss, deterioration of trabecular microarchitecture, and biomechanical dysfunction that may be due to increase intracellular calcium uptake through the TRPV6 calcium channel. Osteoporosis is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to an increased fracture risk. The incidence of osteoporosis increases with age and occurs most frequently in postmenopausal women due to estrogen deficiency, as the balance between bone resorption and bone formation shifts towards increased levels of bone resorption. Among various methods of prevention and treatment for osteoporosis, an increase in calcium intake is the most commonly recommended preventive measure. Kefir is a fermented milk product made with kefir grains that degrade milk proteins into various peptides with health-promoting effects, including immunomodulating-, antithrombotic-, antimicrobial-, and calcium-absorption-enhancing bioactivities. The aim of this study is to investigate the effect of kefir on osteoporosis prophylaxis in an ovariectomized rat model. A total of 56 16-week-old female Sprague-Dawley (SD) rats were divided into 7 experimental groups: sham (normal), OVX/Mock, OVX/1X kefir (164 mg/kg BW/day), OVX/2X kefir (328 mg/kg BW/day), OVX/4X kefir (656 mg/kg BW/day), OVX/ALN (2.5 mg/kg BW/day), and OVX/REBONE (800 mg/kg BW/day). After 12-week treatment with kefir, the bone physiology in the OVX rat model was investigated. Accordingly, the aim of this study was to investigate the possible transport mechanism involved in calcium absorption using the Caco-2 human cell line. A 12-week treatment with kefir on the OVX-induced osteoporosis model reduced the levels of C-terminal telopeptides of type I collagen (CTx), bone turnover markers, and trabecular separation (Tb. Sp.). Additionally, treatment with kefir increased

  14. A universal scaling relationship between body mass and proximal limb bone dimensions in quadrupedal terrestrial tetrapods

    Directory of Open Access Journals (Sweden)

    Campione Nicolás E

    2012-07-01

    Full Text Available Abstract Background Body size is intimately related to the physiology and ecology of an organism. Therefore, accurate and consistent body mass estimates are essential for inferring numerous aspects of paleobiology in extinct taxa, and investigating large-scale evolutionary and ecological patterns in the history of life. Scaling relationships between skeletal measurements and body mass in birds and mammals are commonly used to predict body mass in extinct members of these crown clades, but the applicability of these models for predicting mass in more distantly related stem taxa, such as non-avian dinosaurs and non-mammalian synapsids, has been criticized on biomechanical grounds. Here we test the major criticisms of scaling methods for estimating body mass using an extensive dataset of mammalian and non-avian reptilian species derived from individual skeletons with live weights. Results Significant differences in the limb scaling of mammals and reptiles are noted in comparisons of limb proportions and limb length to body mass. Remarkably, however, the relationship between proximal (stylopodial limb bone circumference and body mass is highly conserved in extant terrestrial mammals and reptiles, in spite of their disparate limb postures, gaits, and phylogenetic histories. As a result, we are able to conclusively reject the main criticisms of scaling methods that question the applicability of a universal scaling equation for estimating body mass in distantly related taxa. Conclusions The conserved nature of the relationship between stylopodial circumference and body mass suggests that the minimum diaphyseal circumference of the major weight-bearing bones is only weakly influenced by the varied forces exerted on the limbs (that is, compression or torsion and most strongly related to the mass of the animal. Our results, therefore, provide a much-needed, robust, phylogenetically corrected framework for accurate and consistent estimation of body mass in

  15. Jumping improves hip and lumbar spine bone mass in prepubescent children: a randomized controlled trial.

    Science.gov (United States)

    Fuchs, R K; Bauer, J J; Snow, C M

    2001-01-01

    Physical activity during childhood is advocated as one strategy for enhancing peak bone mass (bone mineral content [BMC]) as a means to reduce osteoporosis-related fractures. Thus, we investigated the effects of high-intensity jumping on hip and lumbar spine bone mass in children. Eighty-nine prepubescent children between the ages of 5.9 and 9.8 years were randomized into a jumping (n = 25 boys and n = 20 girls) or control group (n = 26 boys and n = 18 girls). Both groups participated in the 7-month exercise intervention during the school day three times per week. The jumping group performed 100, two-footed jumps off 61-cm boxes each session, while the control group performed nonimpact stretching exercises. BMC (g), bone area (BA; cm2), and bone mineral density (BMD; g/cm2) of the left proximal femoral neck and lumbar spine (L1-L4) were assessed by dual-energy X-ray absorptiometry (DXA; Hologic QDR/4500-A). Peak ground reaction forces were calculated across 100, two-footed jumps from a 61-cm box. In addition, anthropometric characteristics (height, weight, and body fat), physical activity, and dietary calcium intake were assessed. At baseline there were no differences between groups for anthropometric characteristics, dietary calcium intake, or bone variables. After 7 months, jumpers and controls had similar increases in height, weight, and body fat. Using repeated measures analysis of covariance (ANCOVA; covariates, initial age and bone values, and changes in height and weight) for BMC, the primary outcome variable, jumpers had significantly greater 7-month changes at the femoral neck and lumbar spine than controls (4.5% and 3.1%, respectively). In repeated measures ANCOVA of secondary outcomes (BMD and BA), BMD at the lumbar spine was significantly greater in jumpers than in controls (2.0%) and approached statistical significance at the femoral neck (1.4%; p = 0.085). For BA, jumpers had significantly greater increases at the femoral neck area than controls (2

  16. X-ray dual energy spectral parameter optimization for bone Calcium/Phosphorus mass ratio estimation

    Science.gov (United States)

    Sotiropoulou, P. I.; Fountos, G. P.; Martini, N. D.; Koukou, V. N.; Michail, C. M.; Valais, I. G.; Kandarakis, I. S.; Nikiforidis, G. C.

    2015-09-01

    Calcium (Ca) and Phosphorus (P) bone mass ratio has been identified as an important, yet underutilized, risk factor in osteoporosis diagnosis. The purpose of this simulation study is to investigate the use of effective or mean mass attenuation coefficient in Ca/P mass ratio estimation with the use of a dual-energy method. The investigation was based on the minimization of the accuracy of Ca/P ratio, with respect to the Coefficient of Variation of the ratio. Different set-ups were examined, based on the K-edge filtering technique and single X-ray exposure. The modified X-ray output was attenuated by various Ca/P mass ratios resulting in nine calibration points, while keeping constant the total bone thickness. The simulated data were obtained considering a photon counting energy discriminating detector. The standard deviation of the residuals was used to compare and evaluate the accuracy between the different dual energy set-ups. The optimum mass attenuation coefficient for the Ca/P mass ratio estimation was the effective coefficient in all the examined set-ups. The variation of the residuals between the different set-ups was not significant.

  17. Rapidly growing Brtl/+ mouse model of osteogenesis imperfecta improves bone mass and strength with sclerostin antibody treatment.

    Science.gov (United States)

    Sinder, Benjamin P; Salemi, Joseph D; Ominsky, Michael S; Caird, Michelle S; Marini, Joan C; Kozloff, Kenneth M

    2015-02-01

    Osteogenesis imperfecta (OI) is a heritable collagen-related bone dysplasia, characterized by brittle bones with increased fracture risk that presents most severely in children. Anti-resorptive bisphosphonates are frequently used to treat pediatric OI and controlled clinical trials have shown that bisphosphonate therapy improves vertebral outcomes but has little benefit on long bone fracture rate. New treatments which increase bone mass throughout the pediatric OI skeleton would be beneficial. Sclerostin antibody (Scl-Ab) is a potential candidate anabolic therapy for pediatric OI and functions by stimulating osteoblastic bone formation via the canonical Wnt signaling pathway. To explore the effect of Scl-Ab on the rapidly growing OI skeleton, we treated rapidly growing 3week old Brtl/+ mice, harboring a typical heterozygous OI-causing Gly→Cys substitution on col1a1, for 5weeks with Scl-Ab. Scl-Ab had anabolic effects in Brtl/+ and led to new cortical bone formation and increased cortical bone mass. This anabolic action resulted in improved mechanical strength to WT Veh levels without altering the underlying brittle nature of the material. While Scl-Ab was anabolic in trabecular bone of the distal femur in both genotypes, the effect was less strong in these rapidly growing Brtl/+ mice compared to WT. In conclusion, Scl-Ab was able to stimulate bone formation in a rapidly growing Brtl/+ murine model of OI, and represents a potential new therapy to improve bone mass and reduce fracture risk in pediatric OI.

  18. Effects of Obesity on Bone Mass and Quality in Ovariectomized Female Zucker Rats

    Directory of Open Access Journals (Sweden)

    Rafaela G. Feresin

    2014-01-01

    Full Text Available Obesity and osteoporosis are two chronic conditions that have been increasing in prevalence. Despite prior data supporting the positive relationship between body weight and bone mineral density (BMD, recent findings show excess body weight to be detrimental to bone mass, strength, and quality. To evaluate whether obesity would further exacerbate the effects of ovariectomy on bone, we examined the tibiae and fourth lumbar (L4 vertebrae from leptin receptor-deficient female (Leprfa/fa Zucker rats and their heterozygous lean controls (Leprfa/+ that were either sham-operated or ovariectomized (Ovx. BMD of L4 vertebra was measured using dual-energy X-ray absorptiometry, and microcomputed tomography was used to assess the microstructural properties of the tibiae. Ovariectomy significantly (P<0.001 decreased the BMD of L4 vertebrae in lean and obese Zucker rats. Lower trabecular number and greater trabecular separation (P<0.001 were also observed in the tibiae of lean- and obese-Ovx rats when compared to sham rats. However, only the obese-Ovx rats had lower trabecular thickness (Tb.Th (P<0.005 than the other groups. These findings demonstrated that ovarian hormone deficiency adversely affected bone mass and quality in lean and obese rats while obesity only affected Tb.Th in Ovx-female Zucker rats.

  19. Mid-Childhood Bone Mass After Exposure to Repeat Doses of Antenatal Glucocorticoids: A Randomized Trial.

    Science.gov (United States)

    McKinlay, Christopher J D; Cutfield, Wayne S; Battin, Malcolm R; Dalziel, Stuart R; Crowther, Caroline A; Harding, Jane E

    2017-05-01

    Treatment of women at risk for preterm birth with repeat doses of glucocorticoids reduces neonatal morbidity, but could have adverse effects on skeletal development. We assessed whether exposure to repeat antenatal betamethasone alters bone mass in children whose mothers participated in the Australasian Collaborative Trial of Repeat Doses of Corticosteroids. Women were randomized to a single dose of betamethasone or placebo, ≥7 days after an initial course of glucocorticoids, repeated each week that they remained at risk for preterm birth at children underwent whole-body dual-energy radiograph absorptiometry at 6 to 8 years' corrected age. Of 212 eligible childhood survivors, 185 were studied (87%; 91 repeat betamethasone group; 94 placebo [single course] group). Children exposed to repeat antenatal betamethasone and those exposed to placebo had similar whole-body bone mineral content (median repeat betamethasone: 553 g, interquartile range: 442-712 g; placebo: 567 g, interquartile range: 447-750 g; geometric mean ratio: 0.99; 95% confidence interval: 0.94-1.03, P = .55) and bone area (median repeat betamethasone 832 cm(2), interquartile range: 693-963 cm(2); placebo: 822 cm(2), interquartile range: 710-1020 cm(2); geometric mean ratio: 0.99, 95% confidence interval: 0.92-1.07, P = .75). Exposure to repeat doses of antenatal betamethasone compared with a single course of glucocorticoids does not alter bone mass in mid-childhood. Copyright © 2017 by the American Academy of Pediatrics.

  20. Microtubule assembly affects bone mass by regulating both osteoblast and osteoclast functions: stathmin deficiency produces an osteopenic phenotype in mice.

    Science.gov (United States)

    Liu, Hongbin; Zhang, Rongrong; Ko, Seon-Yle; Oyajobi, Babatunde O; Papasian, Christopher J; Deng, Hong-Wen; Zhang, Shujun; Zhao, Ming

    2011-09-01

    Cytoskeleton microtubules regulate various cell signaling pathways that are involved in bone cell function. We recently reported that inhibition of microtubule assembly by microtubule-targeting drugs stimulates osteoblast differentiation and bone formation. To further elucidate the role of microtubules in bone homeostasis, we characterized the skeletal phenotype of mice null for stathmin, an endogenous protein that inhibits microtubule assembly. In vivo micro-computed tomography (µCT) and histology revealed that stathmin deficiency results in a significant reduction of bone mass in adult mice concurrent with decreased osteoblast and increased osteoclast numbers in bone tissues. Phenotypic analyses of primary calvarial cells and bone marrow cells showed that stathmin deficiency inhibited osteoblast differentiation and induced osteoclast formation. In vitro overexpression studies showed that increased stathmin levels enhanced osteogenic differentiation of preosteoblast MC3T3-E1 cells and mouse bone marrow-derived cells and attenuated osteoclast formation from osteoclast precursor Raw264.7 cells and bone marrow cells. Results of immunofluorescent studies indicated that overexpression of stathmin disrupted radial microtubule filaments, whereas deficiency of stathmin stabilized the microtubule network structure in these bone cells. In addition, microtubule-targeting drugs that inhibit microtubule assembly and induce osteoblast differentiation lost these effects in the absence of stathmin. Collectively, these results suggest that stathmin, which alters microtubule dynamics, plays an essential role in maintenance of postnatal bone mass by regulating both osteoblast and osteoclast functions in bone. \\

  1. Associations between lower extremity muscle mass and metabolic parameters related to obesity in Japanese obese patients with type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Hidetaka Hamasaki

    2015-05-01

    Full Text Available Background. Age-related loss of muscle mass (sarcopenia increases the incidence of obesity in the elderly by reducing physical activity. This sarcopenic obesity may become self-perpetuating, increasing the risks for metabolic syndrome, disability, and mortality. We investigated the associations of two sarcopenic indices, the ratio of lower extremity muscle mass to body weight (L/W ratio and the ratio of lower extremity muscle mass to upper extremity muscle mass (L/U ratio, with metabolic parameters related to obesity in patients with type 2 diabetes and obesity.Methods. Of 148 inpatients with type 2 diabetes treated between October 2013 and April 2014, we recruited 26 with obesity but no physical disability. Daily physical activity was measured by a triaxial accelerometer during a period of hospitalization, and which was also evaluated by our previously reported non-exercise activity thermogenesis questionnaire. We measured body composition by bioelectrical impedance and investigated the correlations of L/W and L/U ratios with body weight, body mass index (BMI, waist circumference (WC, waist-to-hip ratio (WHR, visceral fat area, subcutaneous fat area, serum lipid profile, and daily physical activity.Results. The L/W ratio was significantly and negatively correlated with BMI, WC, WHR, body fat mass, body fat percentage, subcutaneous fat area, and serum free fatty acid concentration, was positively correlated with daily physical activity: the locomotive non-exercise activity thermogenesis score, but was not correlated with visceral fat area. The L/U ratio was significantly and positively correlated with serum high-density lipoprotein cholesterol.Conclusions. High L/W and L/U ratios, indicative of relatively preserved lower extremity muscle mass, were predictive of improved metabolic parameters related to obesity. Preserved muscle fitness in obesity, especially of the lower extremities, may prevent sarcopenic obesity and lower associated risks for

  2. Effect of estrogenic compounds (estrogen or phytoestrogens) combined with exercise on bone and muscle mass in older individuals.

    Science.gov (United States)

    Chilibeck, Philip D; Cornish, Stephen M

    2008-02-01

    Exercise has a beneficial effect on bone, possibly by stimulating estrogen receptor alpha. Because estrogen up-regulates this receptor, estrogen therapy combined with exercise training may be optimal for increasing bone mineral density. Studies combining estrogen therapy and exercise training in postmenopausal women show mixed results, but indicate that the combination of interventions may be more effective for increasing bone mass than either intervention alone. Plant-like estrogens (i.e phytoestrogens such as soy isoflavones) may act as weak estrogen agonists or antagonists, have small beneficial effects on bone, and may interact with exercise for increasing bone mineral density. Phytoestrogen derived from flaxseed (flax lignans) has not been evaluated as extensively as soy isoflavones and thus its effect on bone is difficult to determine. Estrogen or soy isoflavones given to postmenopausal women results in a small increase in lean tissue mass that may be mediated through estrogen receptor alpha on muscle or through decreased inflammation.

  3. CALCIUM REGULATING HORMONES IN SERUM AND BONE MASS DENSITY IN PATIENTS WITH DIABETES MELLITUS

    Institute of Scientific and Technical Information of China (English)

    颜晓东; 黄忠; 胡映玉

    2003-01-01

    Objective To investigate the changes of calcium regulating hormones in serum and bone mass in patients with diabetes mellitus.Methods The levels of estradiol (E2), testosterone (T), total triiodthyronine (TT3), total thyroid hormone(TT4), parathyroid hormone (PTH-SP), calci-tonin (CT) were measured in serum of 227 patients with diabetes and 268 healthy controls by radioim-munoassay, and bone mass density (BMD) at lumbar vertebrae, hip, foream were measured by dual energy X-ray absorptiometry (DEXA). The subjects were divided into three age groups.Results T of male in three age subgroups of diabetes was significantly lower (P<0.01 or P<0.05) and PTH was significantly higher (P< 0.001 or P< 0.01) than that in controls. BMD at lumbar 3, lumbar 4 in diabetes was lower than that in controls but BMD at hip, foream was higher.Conclusion The level of T declines and PTH increases in diabetes. Bone mass loss mostly occurs at lumbar vertebrae in diabetes patients.

  4. The results of bone deformity correction using a spider frame with web-based software for lower extremity long bone deformities

    Directory of Open Access Journals (Sweden)

    Tekin Ali Çağrı

    2016-01-01

    Full Text Available Aim: To present the functional and radiological results and evaluate the effectiveness of a computer-assisted external fixator (spider frame in patients with lower extremity shortness and deformity. Materials and methods: The study comprised 17 patients (14 male, 3 female who were treated for lower extremity long bone deformity and shortness between 2012 and 2015 using a spider frame. The procedure’s level of difficulty was determined preoperatively using the Paley Scale. Postoperatively, the results for the patients who underwent tibial operations were evaluated using the Paley criteria modified by ASAMI, and the results for the patients who underwent femoral operations were evaluated according to the Paley scoring system. The evaluations were made by calculating the External Fixator and Distraction indexes. Results: The mean age of the patients was 24.58 years (range, 5–51 years. The spider frame was applied to the femur in 10 patients and to the tibia in seven. The mean follow-up period was 15 months (range, 6–31 months from the operation day, and the mean amount of lengthening was 3.0 cm (range, 1–6 cm. The mean duration of fixator application was 202.7 days (range, 104–300 days. The mean External Fixator Index was 98 days/cm (range, 42–265 days/cm. The mean Distraction Index was 10.49 days/cm (range, 10–14 days/cm. Conclusion: The computer-assisted external fixator system (spider frame achieves single-stage correction in cases of both deformity and shortness. The system can be applied easily, and because of its high-tech software, it offers the possibility of postoperative treatment of the deformity.

  5. No association between the aluminium content of trabecular bone and bone density, mass or size of the proximal femur in elderly men and women

    Directory of Open Access Journals (Sweden)

    Mallmin Hans

    2006-08-01

    Full Text Available Abstract Background Aluminium is considered a bone toxic metal since poisoning can lead to aluminium-induced bone disease in patients with chronic renal failure. Healthy subjects with normal renal function retain 4% of the aluminium consumed. They might thus also accumulate aluminium and eventually be at risk of long-term low-grade aluminium intoxication that can affect bone health. Methods We therefore examined 62 patients with femoral neck fractures or osteoarthritis of the hip (age range 38–93, with the aim of examining whether aluminium in bone is associated with bone-mineral density (BMD, content (BMC or width of the femoral neck measured by dual-energy X-ray absorptiometry (DXA. During operations bone biopsies were taken from the trabecular bone of the proximal femur. The samples were measured for their content of aluminium using a mass spectrometer. Results No significant association between the aluminium content in bone and femoral neck BMD, BMC or width could be found after multivariate adjustment. Conclusion Our results indicate that the accumulated aluminium content in bone during life does not substantially influence the extent of osteoporosis.

  6. Bone

    Science.gov (United States)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  7. Discovery of Three Pulsating, Mixed-atmosphere, Extremely Low-mass White Dwarf Precursors

    Science.gov (United States)

    Gianninas, A.; Curd, Brandon; Fontaine, G.; Brown, Warren R.; Kilic, Mukremin

    2016-05-01

    We report the discovery of pulsations in three mixed-atmosphere, extremely low-mass white dwarf (ELM WD, M ≤slant 0.3 M ⊙) precursors. Following the recent discoveries of pulsations in both ELM and pre-ELM WDs, we targeted pre-ELM WDs with mixed H/He atmospheres with high-speed photometry. We find significant optical variability in all three observed targets with periods in the range 320-590 s, consistent in timescale with theoretical predictions of p-mode pulsations in mixed-atmosphere ≈0.18 M ⊙ He-core pre-ELM WDs. This represents the first empirical evidence that pulsations in pre-ELM WDs can only occur if a significant amount of He is present in the atmosphere. Future, more extensive, timeseries photometry of the brightest of the three new pulsators offers an excellent opportunity to constrain the thickness of the surface H layer, which regulates the cooling timescales for ELM WDs. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).

  8. Discovery of Three Pulsating, Mixed Atmosphere, Extremely Low-Mass White Dwarf Precursors

    CERN Document Server

    Gianninas, A; Fontaine, G; Browm, Warren R; Kilic, Mukremin

    2016-01-01

    We report the discovery of pulsations in three mixed atmosphere, extremely low-mass white dwarf (ELM WD, M $<$ 0.3 M$_{\\odot}$) precursors. Following the recent discoveries of pulsations in both ELM and pre-ELM WDs, we targeted pre-ELM WDs with mixed H/He atmospheres with high-speed photometry. We find significant optical variability in all three observed targets with periods in the range 320--590 s, consistent in time-scale with theoretical predictions of p-mode pulsations in mixed-atmosphere $\\approx$ 0.18 M$_{\\odot}$ He-core pre-ELM WDs. This represents the first empirical evidence that pulsations in pre-ELM WDs can only occur if a significant amount of He is present in the atmosphere. Future, more extensive, time-series photometry of the brightest of the three new pulsators offers an excellent opportunity to constrain the thickness of the surface H layer which regulates the cooling timescales for ELM WDs.

  9. Properties of the Fast Forward Shock Driven by the July 23 2012 Extreme Coronal Mass Ejection

    CERN Document Server

    Riley, Pete; Giacalone, Joe; Lario, David; Liu, Ying

    2015-01-01

    Late on July 23, 2012, the STEREO-A spacecraft encountered a fast forward shock driven by a coronal mass ejection launched from the Sun earlier that same day. The estimated travel time of the disturbance ($\\sim 20$ hrs), together with the massive magnetic field strengths measured within the ejecta ($> 100$nT), made it one of the most extreme events observed during the space era. In this study, we examine the properties of the shock wave. Because of an instrument malfunction, plasma measurements during the interval surrounding the CME were limited, and our approach has been modified to capitalize on the available measurements and suitable proxies, where possible. We were able to infer the following properties. First, the shock normal was pointing predominantly in the radial direction (${\\bf n} = 0.97 {\\bf e}_r -0.09 {\\bf e}_t -0.23 {\\bf e}_n$). Second, the angle between ${\\bf n}$ and the upstream magnetic field, $\\theta_{Bn}$, was estimated to be $\\approx 34^{\\circ}$, making the shock "quasi-parallel," and sup...

  10. Fast Evolution and Waveform Generator for Extreme-Mass-Ratio Inspirals in Equatorial-Circular Orbits

    CERN Document Server

    Han, Wen-Biao

    2016-01-01

    In this paper we discuss the development of a fast and accurate waveform model for the quasi-circular orbital evolution of extreme-mass-ratio-inspirals (EMRIs). This model simply employs the data of a few numerical Teukoulsky-based energy fluxes and waveforms to fit out a set of polynomials for the entire fluxes and waveforms. These obtained polynomials are accurate enough in the entire evolution domain, and much more accurate than the resummation post-Newtonian (PN) energy fluxes and waveforms, especially when the spin of a black hole becomes large. The dynamical equation we adopted for orbital revolution is the effective-one-body (EOB) formalism. Because of the simplified expressions, the efficiency of calculating the orbital evolution with our polynomials is also better than the traditional method which uses the resummed PN analytical fluxes. Our model should be useful in calculation of waveform templates of EMRIs for the gravitational wave detectors such as the evolved Laser Interferometer Space Antenna (...

  11. Lean Mass and Fat Mass as Mediators of the Relationship Between Physical Activity and Bone Mineral Density in Postmenopausal Women.

    Science.gov (United States)

    Xiang, Jing; Chen, Yongjie; Wang, Yupeng; Su, Shaofei; Wang, Xinyu; Xie, Biao; Zhang, Qiuju; Liu, Meina

    2017-05-01

    The relationship between physical activity (PA) and bone health is well known, but the role of lean mass (LM) and fat mass (FM) in this relationship remains uncertain. Therefore, the aim of this study was to examine the mediating effect of LM and FM on the relationship between PA and bone mineral density (BMD) in postmenopausal women. This cross-sectional study involved 282 postmenopausal women aged between 50 and 65 year, who were randomly selected from Hongqi community of Harbin City in China. PA was measured using an International PA Questionnaire. Body composition, BMD of the lumbar spine, hip, and total body were measured using dual-energy X-ray absorptiometry. Mediation analysis was performed to investigate the mediating effect of LM and FM on the relationship between PA and BMD. In partial correlation analysis, PA, LM, and FM were positively related to BMD. Positive correlation was found between PA and LM. There were significant differences in BMD between different categories of PA, but the differences disappeared after adjusting for LM. Mediation analysis showed that LM and FM played a mediating role in the relationship between PA and BMD. LM appeared to mediate the effect of BMD in the spine, hip, and total body by 26.91%, 19.55% and 47.98%, respectively; and FM was 22.23%, 27.97%, and 33.02%, respectively. LM and FM affected the relationship between PA and BMD as mediator. Postmenopausal women with high LM and FM had more BMD.

  12. Visceral fat is more important than peripheral fat for endometrial thickness and bone mass in healthy postmenopausal women

    DEFF Research Database (Denmark)

    Warming, Lise; Ravn, Pernille; Christiansen, Claus

    2003-01-01

    as double-layer thickness. Body composition was measured by dual energy x-ray absorptiometry, which divides the body into fat mass, lean mass, and bone mass, both for the total body and regional body compartments. An abdominal region was inserted manually. Statistics were Pearson correlations and analysis...

  13. The atherogenic Scarb1 null mouse model shows a high bone mass phenotype.

    Science.gov (United States)

    Martineau, Corine; Martin-Falstrault, Louise; Brissette, Louise; Moreau, Robert

    2014-01-01

    Scavenger receptor class B, type I (SR-BI), the Scarb1 gene product, is a receptor associated with cholesteryl ester uptake from high-density lipoproteins (HDL), which drives cholesterol movement from peripheral tissues toward the liver for excretion, and, consequently, Scarb1 null mice are prone to atherosclerosis. Because studies have linked atherosclerosis incidence with osteoporosis, we characterized the bone metabolism in these mice. Bone morphometry was assessed through microcomputed tomography and histology. Marrow stromal cells (MSCs) were used to characterize influence of endogenous SR-BI in cell functions. Total and HDL-associated cholesterol in null mice were increased by 32-60%, correlating with its role in lipoprotein metabolism. Distal metaphyses from 2- and 4-mo-old null mice showed correspondingly 46 and 37% higher bone volume fraction associated with a higher number of trabeculae. Histomorphometric analyses in 2-mo-old null male mice revealed 1.42-fold greater osteoblast surface, 1.37-fold higher percent mineralizing surface, and 1.69-fold enhanced bone formation rate. In vitro assays for MSCs from null mice revealed 37% higher proliferation rate, 48% more alkaline phosphatase activity, 70% greater mineralization potential and a 2-fold osterix (Sp7) expression, yet a 0.5-fold decrease in caveolin-1 (Cav1) expression. Selective uptake levels of HDL-associated cholesteryl oleate and estradiol were similar between MSC from wild-type and Scarb1 null mice, suggesting that its contribution to this process is not its main role in these cells. However, Scarb1 knockout stunted the HDL-dependent regulation of Cav1 genic expression. Scarb1 null mice are not prone to osteoporosis but show higher bone mass associated with enhanced bone formation.

  14. Osteoporosis and low bone mass at the femur neck or lumbar spine in older adults: United States, 2005-2008

    Science.gov (United States)

    Many current clinical guidelines recommend that assessment of osteoporosis or low bone mass, as defined by the World Health Organization (WHO) (1), be based on bone mineral density at either the femur neck region of the proximal femur (hip) or the lumbar spine (2,3). This data brief presents the mos...

  15. Bone mass in Indian children--relationships to maternal nutritional status and diet during pregnancy: the Pune Maternal Nutrition Study.

    Science.gov (United States)

    Ganpule, A; Yajnik, C S; Fall, C H D; Rao, S; Fisher, D J; Kanade, A; Cooper, C; Naik, S; Joshi, N; Lubree, H; Deshpande, V; Joglekar, C

    2006-08-01

    Bone mass is influenced by genetic and environmental factors. Recent studies have highlighted associations between maternal nutritional status during pregnancy and bone mass in the offspring. We hypothesized that maternal calcium intakes and circulating micronutrients during pregnancy are related to bone mass in Indian children. DESIGN/SETTING/PARTICIPANTS/MAIN OUTCOME MEASURES: Nutritional status was measured at 18 and 28 wk gestation in 797 pregnant rural Indian women. Measurements included anthropometry, dietary intakes (24-h recall and food frequency questionnaire), physical workload (questionnaire), and circulating micronutrients (red cell folate and plasma ferritin, vitamin B12, and vitamin C). Six years postnatally, total body and total spine bone mineral content and bone mineral density (BMD) were measured using dual-energy x-ray absorptiometry (DXA) in the children (n = 698 of 762 live births) and both parents. Both parents' DXA measurements were positively correlated with the equivalent measurements in the children (P pregnancy (milk, milk products, pulses, non-vegetarian foods, green leafy vegetables, fruit) had higher total and spine bone mineral content and BMD, and children of mothers with higher folate status at 28 wk gestation had higher total and spine BMD, independent of parental size and DXA measurements. Modifiable maternal nutritional factors may influence bone health in the offspring. Fathers play a role in determining their child's bone mass, possibly through genetic mechanisms or through shared environment.

  16. Combined treatment with GH and IGF-I: additive effect on cortical bone mass but not on linear bone growth in female rats.

    Science.gov (United States)

    Sundström, Katja; Cedervall, Therese; Ohlsson, Claes; Camacho-Hübner, Cecilia; Sävendahl, Lars

    2014-12-01

    The growth-promoting effect of combined therapy with GH and IGF-I in normal rats is not known. We therefore investigated the efficacy of treatment with recombinant human (rh)GH and/or rhIGF-I on longitudinal bone growth and bone mass in intact, prepubertal, female Sprague-Dawley rats. rhGH was injected twice daily sc (5 mg/kg·d) and rhIGF-I continuously infused sc (2.2 or 4.4 mg/kg·d) for 28 days. Longitudinal bone growth was monitored by weekly x-rays of tibiae and nose-anus length measurements, and tibial growth plate histomorphology was analyzed. Bone mass was evaluated by peripheral quantitative computed tomography. In addition, serum levels of IGF-I, rat GH, acid labile subunit, IGF binding protein-3, 150-kDa ternary complex formation, and markers of bone formation and degradation were measured. Monotherapy with rhGH was more effective than rhIGF-I (4.4 mg/kg·d) to increase tibia and nose-anus length, whereas combined therapy did not further increase tibia, or nose-anus, lengths or growth plate height. In contrast, combined rhGH and rhIGF-I (4.4 mg/kg·d) therapy had an additive stimulatory effect on cortical bone mass vs rhGH alone. Combined treatment with rhGH and rhIGF-I resulted in markedly higher serum IGF-I concentrations vs rhGH alone but did not compromise the endogenous secretion of GH. We conclude that rhIGF-I treatment augments cortical bone mass but does not further improve bone growth in rhGH-treated young, intact, female rats.

  17. Effects of a 6-month football intervention program on bone mass and physical fitness in overweight children

    DEFF Research Database (Denmark)

    Seabra, André; Serra, Hugo; Seabra, Ana;

    2016-01-01

    Introduction: Physical activity is an important medium for improving bone mass and physical fitness of children, and as such is often emphasized in intervention programs with overweight/obesity children. Only few studies have examined the impact of a specific team sport intervention on the bone...... mass and physical fitness in overweight children. This study examined the effects of a 6-month football intervention program in bone mass and physical fitness of overweight children. Methods: Nine boys (8-12 years; body mass index ≥ 85th percentile) participated in a structured 6-month football program...... bone and physical fitness variables assessed, although FG has shown a higher increase in mean values across intervention, no significant differences were found between groups (p>0.05). Conclusions: These findings suggest that a 6-month football intervention program in overweight children was effective...

  18. 'Sink or swim': an evaluation of the clinical characteristics of individuals with high bone mass.

    LENUS (Irish Health Repository)

    Gregson, C L

    2011-04-01

    High bone mineral density on routine dual energy X-ray absorptiometry (DXA) may indicate an underlying skeletal dysplasia. Two hundred fifty-eight individuals with unexplained high bone mass (HBM), 236 relatives (41% with HBM) and 58 spouses were studied. Cases could not float, had mandible enlargement, extra bone, broad frames, larger shoe sizes and increased body mass index (BMI). HBM cases may harbour an underlying genetic disorder. INTRODUCTION: High bone mineral density is a sporadic incidental finding on routine DXA scanning of apparently asymptomatic individuals. Such individuals may have an underlying skeletal dysplasia, as seen in LRP5 mutations. We aimed to characterize unexplained HBM and determine the potential for an underlying skeletal dysplasia. METHODS: Two hundred fifty-eight individuals with unexplained HBM (defined as L1 Z-score ≥ +3.2 plus total hip Z-score ≥ +1.2, or total hip Z-score ≥ +3.2) were recruited from 15 UK centres, by screening 335,115 DXA scans. Unexplained HBM affected 0.181% of DXA scans. Next 236 relatives were recruited of whom 94 (41%) had HBM (defined as L1 Z-score + total hip Z-score ≥ +3.2). Fifty-eight spouses were also recruited together with the unaffected relatives as controls. Phenotypes of cases and controls, obtained from clinical assessment, were compared using random-effects linear and logistic regression models, clustered by family, adjusted for confounders, including age and sex. RESULTS: Individuals with unexplained HBM had an excess of sinking when swimming (7.11 [3.65, 13.84], p < 0.001; adjusted odds ratio with 95% confidence interval shown), mandible enlargement (4.16 [2.34, 7.39], p < 0.001), extra bone at tendon\\/ligament insertions (2.07 [1.13, 3.78], p = 0.018) and broad frame (3.55 [2.12, 5.95], p < 0.001). HBM cases also had a larger shoe size (mean difference 0.4 [0.1, 0.7] UK sizes, p = 0.009) and increased BMI (mean difference 2.2 [1.3, 3.1] kg\\/m(2

  19. Maternal dietary patterns during pregnancy and childhood bone mass: a longitudinal study.

    Science.gov (United States)

    Cole, Zoe A; Gale, Catharine R; Javaid, M Kassim; Robinson, Sian M; Law, Catherine; Boucher, Barbara J; Crozier, Sarah R; Godfrey, Keith M; Dennison, Elaine M; Cooper, Cyrus

    2009-04-01

    Maternal nutrition is a potentially important determinant of intrauterine skeletal development. Previous studies have examined the effects of individual nutrients, but the pattern of food consumption may be of greater relevance. We therefore examined the relationship between maternal dietary pattern during pregnancy and bone mass of the offspring at 9 yr of age. We studied 198 pregnant women 17-43 yr of age and their offspring at 9 yr of age. Dietary pattern was assessed using principal component analysis from a validated food frequency questionnaire. The offspring underwent measurements of bone mass using DXA at 9 yr of age. A high prudent diet score was characterized by elevated intakes of fruit, vegetables, and wholemeal bread, rice, and pasta and low intakes of processed foods. Higher prudent diet score in late pregnancy was associated with greater (p < 0.001) whole body and lumbar spine BMC and areal BMD in the offspring, after adjustment for sex, socioeconomic status, height, arm circumference, maternal smoking, and vitamin D status. Associations with prudent diet score in early pregnancy were weaker and nonsignificant. We conclude that dietary patterns consistent with current advice for healthy eating during pregnancy are associated with greater bone size and BMD in the offspring at 9 yr of age.

  20. Influences of physical fitness on bone mass in women with fibromyalgia.

    Science.gov (United States)

    Gómez-Cabello, Alba; Vicente-Rodríguez, Germán; Navarro-Vera, Isabel; Martinez-Redondo, Diana; Díez-Sánchez, Carmen; Casajús, José Antonio

    2015-04-01

    The aim of this study was to provide information about the relationship of bone mineral content (BMC) and density (BMD) with some physical-fitness-related variables in a sample of women with fibromyalgia (FM) and age-matched women without FM. Twenty-eight women clinically diagnosed with FM (age 51.1 ± 8.4 yr, M ± SD) and 22 age-matched controls participated in the study. Whole-body BMC and BMD, lean mass, handgrip strength, quadriceps strength, and cardiovascular fitness were measured in all participants. The association between physical-fitness variables and bone-related variables was tested by linear regression controlling for body weight as a possible confounder. There were no differences in BMC or BMD between groups. Women with FM had lower values of handgrip strength, quadriceps strength, and VO2peak than the control group. Handgrip strength and aerobic capacity were associated with BMC and BMD and quadriceps strength was associated with BMD in women with FM; however, only VO2peak was associated with BMC in the group of women without FM. Bone mass of women with FM may be more susceptible to changes in physical fitness than that of the women without fibromyalgia.

  1. Patients With High Bone Mass Phenotype Exhibit Enhanced Osteoblast Differentiation and Inhibition of Adipogenesis of Human Mesenchymal Stem Cells

    DEFF Research Database (Denmark)

    Qiu, Weimin; Andersen, Tom; Bollerslev, Jens

    2007-01-01

    to osteoporosis), or LRP5T253 (hMSC-LRP5T253, activation mutation leading to high bone mass). We characterized Wnt signaling activation using a dual luciferase assay, cell proliferation, lineage biomarkers using real-time PCR, and in vivo bone formation. Results: In bone biopsies, we found increased trabecular...... mineralized bone when implanted subcutaneously with hydroxyapatite/tricalcium phosphate in SCID/NOD mice. Conclusions: LRP5 mutations and the level of Wnt signaling determine differentiation fate of hMSCs into osteoblasts or adipocytes. Activation of Wnt signaling can thus provide a novel approach to increase...

  2. Coronal mass ejections and other extreme characteristics of the 2003 October-November solar eruptions

    Science.gov (United States)

    Gopalswamy, N.; Yashiro, S.; Liu, Y.; Michalek, G.; Vourlidas, A.; Kaiser, M. L.; Howard, R. A.

    2005-09-01

    Fast coronal mass ejections (CMEs), X-class flares, solar energetic particle (SEP) events, and interplanetary shocks were abundantly observed during the episode of intense solar activity in late October and early November 2003. Most of the 80 CMEs originated from three active regions (NOAA ARs 484, 486, and 488). We compare the statistical properties of these CMEs with those of the general population of CMEs observed during cycle 23. We find that (1) the 2003 October-November CMEs were fast and wide on the average and hence were very energetic, (2) nearly 20 percent of the ultrafast CMEs (speed ≥2000 km s-1) of cycle 23 occurred during the October-November interval, including the fastest CME of the study period (˜2700 km s-1 on 4 November 2003 at 1954 UT), (3) the rate of full-halo CMEs was nearly four times the average rate during cycle 23, (4) at least sixteen shocks were observed near the Sun, while eight of them were intercepted by spacecraft along the Sun-Earth line, (5) the CMEs were highly geoeffective: the resulting geomagnetic storms were among the most intense of cycle 23, (6) the CMEs were associated with very large SEP events, including the largest event of cycle 23. These extreme properties were commensurate with the size and energy of the associated active regions. This study suggests that the speed of CMEs may not be much higher than ˜3000 km s-1, consistent with the free energy available in active regions. An important practical implication of such a speed limit is that the Sun-Earth travel times of CME-driven shocks may not be less than ˜0.5 day. Two of the shocks arrived at Earth in documented cases of such events since 1859.

  3. Operative Risk for Major Lung Resection Increases at Extremes of Body Mass Index.

    Science.gov (United States)

    Williams, Trevor; Gulack, Brian C; Kim, Sunghee; Fernandez, Felix G; Ferguson, Mark K

    2017-01-01

    Although body mass index (BMI) has been used in risk stratification for lung resection, many models only take obesity into account. Recent studies have demonstrated that underweight patients also experience increased postoperative complications. We explored the relationship of extremes of BMI to outcomes after lung resection for non-small cell cancer. Patients in the Society of Thoracic Surgeons General Thoracic Surgery Database (2009 to 2014) undergoing elective lung resection for cancer were evaluated. Multivariable logistic regression was used to adjust for potential confounders including functional status and spirometry. We evaluated 41,446 patients (median 68 years of age; 53% female) grouped by BMI: underweight (obese I (30 to 34.9 kg/m(2); 18.1%), obese II (35 to 39.9 kg/m(2); 6.4%), and obese III (≥40 kg/m(2); 3.6%). Pulmonary complication rates were higher in underweight and obese III patients compared to normal BMI patients (p Obese III patients had an increased risk of any major postoperative complication (adjusted OR: 1.18, 95% CI: 1.02 to 1.36). Overweight and obese class I to II patients had a lower risk of pulmonary complications and any postoperative event. BMI is associated with postoperative complications after lung resection for cancer. Being underweight or severely overweight is associated with an increased risk of complications, whereas being overweight or moderately obese appears to have a protective effect. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  4. CCD Photometry Of The Extreme Mass Ratio Binary, TYC 1404-1687-1

    Science.gov (United States)

    Faulkner, Danny R.; Samec, Ron; Figg, Evan; Oliver, Bruce; Program, Astronomy; Jones University, Bob; VanHamme, Walter; Interational University, Florida

    2011-01-01

    We report our photometric analysis of the variable, TYC 1404-1687-1 (GSC 1404 1687, Cancer). The images were taken in December, 2008, March 2009 with NURO and 16 January 2009 via remote observing with SARA North. The UBVRI CCD photometry shows that TYC 1404-1687-1 has a totally eclipsing W UMa light curve, yet it has a shallow amplitude (AV 0.4 mag.). We studied the possibility the low amplitude was due to the presence of a third component: we began our analysis with 30% third light as determined from Binary Maker. Next, we performed a BVRI simultaneous WD synthetic light curve analysis. Surprisingly, we obtained two nearly identical sums of square solutions, one with a measurable but small third light component (0-2%) and another with no third light. We conclude that the solution does not require a third light. Our period study yielded 9 new times of minimum light, two from ROTSEI curves, JD Hel Min= 2452721.4226 and 2452728.3972, and the others from our observations: HJD Min I = 2454848.8844 ±0.0014, 2454901.8924 ±0.0006, 2454902.6903 ±0.0014, 2454904.6790 ±0.0058, HJD Min II = 2454823.9678 ±0.0017, 2454827.9618 ±0.0005, 2454901.6927 ±0.0005. Using these, we calculated the first precision ephemeris for this system, HJD Min I = 2454902.6912 ±0.0009 + 0.3985874 ±0.0000003 d*E. UBVRCIC standard magnitudes were determined. We find that the comparison star (GSC 1404 0119) is a late G-type dwarf while the check star (GSC 1404 0587) is a mid F-type dwarf. The binary is an F0V contact binary. We also performed a number of solutions (a q-search) which minimized at a mass ratio near 0.2. Our WD solution gave a fill-out of 45%. No spots are needed in the solution. So we find that TYC 1404-1687-1 is among the once rare, but growing number, of low amplitude-extreme mass ratio, totally eclipsing binaries.

  5. Vitamin D and estrogen receptor-alpha genotype and indices of bone mass and bone turnover in Danish girls

    DEFF Research Database (Denmark)

    Cusack, S.; Mølgaard, C.; Michaelsen, K. F.

    2006-01-01

    (VDR) (FokI, TaqI) and estrogen receptor-alpha (ER alpha) (PvuII, XbaI), and bone mineral density (BMD), bone mineral content (BMC), and markers of bone turnover in 224 Danish girls aged 11-12 years. BMD and BMC were measured by dual-energy X-ray absorptiometry. Serum osteocalcin, 25(OH...

  6. Influence of liver enzyme induction caused by diphenylhydantoin and diazepam on bone mass of rats.

    Science.gov (United States)

    Tesseromatis, C; Galanopoulou, P; Varonos, D

    1980-01-01

    25 albino rats of Wistar strain were used for the study. They were divided into three groups. Animals of the first group (n = 10) were treated with Diphenylhydantoin in a daily dose of 70 mg/kg for three months. Animals of the second group (n = 10) were treated with Diazepam in a daily dose of 10 mg/kg for 3 months. Animals of the third group (n = 5) were treated with 5% acacia oil for the same period of time. Food and water consumption together with motor activity were measured. As indices of enzyme induction, D-Glucaric acid and liver weight were determined. Also the following bone indices were determined: femur Ca/femur weight, femur Ca/body weight, humerus Ca/humerus weight, humerus Ca/body weight, femur specific weight, humerus specific weight. Statistically significant alterations of bone mass were found.

  7. The effects of body mass index on the hereditary influences that determine peak bone mass in mother-daughter pairs (KNHANES V).

    Science.gov (United States)

    Kim, K M; Kim, Y J; Choi, S H; Lim, S; Moon, J H; Kim, J H; Kim, S W; Jang, H C; Shin, C S

    2016-06-01

    A daughter's bone mineral density (BMD) is significantly correlated with her mother's BMD, but the daughter's body mass index (BMI) could modulate this association. Maternal inheritance dominantly affects daughters with a lower BMI, but BMI could compensate for hereditary influences in daughters with a higher BMI in terms of daughter's BMD. Achieving optimal peak bone mass at a young age is the best way to protect against future osteoporosis and subsequent fractures. Although environmental components influence bone mass accrual, but peak bone mass is largely programmed by inheritance. The aims of this study were to investigate the influence of maternal inheritance on the daughter's bone mass and to assess whether these influences differ according to the daughter's body mass index (BMI). We used data obtained from the 2010 Korean National Health and Nutrition Examination Survey V and included 187 mother-daughter pairs. Bone mineral density (BMD) was measured at the lumbar spine (LS), femur neck (FN), and total hip (TH) by using dual-energy X-ray absorptiometry (DXA). The daughter group was stratified into two groups according to the mean BMI (21.4 kg/m(2)). The daughters' BMD correlated significantly with both their BMI and their mothers' Z-score for each skeletal site. In the daughters with a lower BMI (≤21.4 kg/m(2)), the BMDs at the FN and TH were affected more by the mothers' Z-score than by the daughters' BMI. Meanwhile, the influence of the daughters' BMI on their BMD was higher than that of their mothers' Z-score in daughters with a higher BMI (>21.4 kg/m(2)). Moreover, the mothers' Z-scores were a significant predictor of their daughters having Z-scores BMI. This study suggests that maternal inheritance is an important determinant of the daughters' bone mass, but that this hereditary factor may vary according to the daughters' BMI.

  8. Discovery of Seven Companions to Intermediate Mass Stars with Extreme Mass Ratios in the Scorpius-Centaurus Association

    CERN Document Server

    Hinkley, Sasha; Ireland, Michael J; Cheetham, Anthony; Carpenter, John M; Tuthill, Peter; Lacour, Sylvestre; Evans, Thomas M; Haubois, Xavier

    2015-01-01

    We report the detection of seven low mass companions to intermediate-mass stars (SpT B/A/F; $M$$\\approx$1.5-4.5 solar masses) in the Scorpius-Centaurus Association using nonredundant aperture masking interferometry. Our newly detected objects have contrasts $\\Delta L'$$\\approx$4-6, corresponding to masses as low as $\\sim$20 Jupiter masses and mass ratios of $q$$\\approx$0.01-0.08, depending on the assumed age of the target stars. With projected separations $\\rho$$\\approx$10-30 AU, our aperture masking detections sample an orbital region previously unprobed by conventional adaptive optics imaging of intermediate mass Scorpius-Centaurus stars covering much larger orbital radii ($\\approx$30-3000 AU). At such orbital separations, these objects resemble higher mass versions of the directly imaged planetary mass companions to the 10-30 Myr, intermediate-mass stars HR 8799, $\\beta$ Pictoris, and HD95086. These newly discovered companions span the brown dwarf desert, and their masses and orbital radii provide a new co...

  9. Bone protein “extractomics”: comparing the efficiency of bone protein extractions of Gallus gallus in tandem mass spectrometry, with an eye towards paleoproteomics

    Directory of Open Access Journals (Sweden)

    Elena R. Schroeter

    2016-10-01

    Full Text Available Proteomic studies of bone require specialized extraction protocols to demineralize and solubilize proteins from within the bone matrix. Although various protocols exist for bone protein recovery, little is known about how discrete steps in each protocol affect the subset of the bone proteome recovered by mass spectrometry (MS analyses. Characterizing these different “extractomes” will provide critical data for development of novel and more efficient protein extraction methodologies for fossils. Here, we analyze 22 unique sub-extractions of chicken bone and directly compare individual extraction components for their total protein yield and diversity and coverage of bone proteins identified by MS. We extracted proteins using different combinations and ratios of demineralizing reagents, protein-solubilizing reagents, and post-extraction buffer removal methods, then evaluated tryptic digests from 20 µg aliquots of each fraction by tandem MS/MS on a 12T FT-ICR mass spectrometer. We compared total numbers of peptide spectral matches, peptides, and proteins identified from each fraction, the redundancy of protein identifications between discrete steps of extraction methods, and the sequence coverage obtained for select, abundant proteins. Although both alpha chains of collagen I (the most abundant protein in bone were found in all fractions, other collagenous and non-collagenous proteins (e.g., apolipoprotein, osteonectin, hemoglobin were differentially identified. We found that when a standardized amount of extracted proteins was analyzed, extraction steps that yielded the most protein (by weight from bone were often not the ones that produced the greatest diversity of bone proteins, or the highest degree of protein coverage. Generally, the highest degrees of diversity and coverage were obtained from demineralization fractions, and the proteins found in the subsequent solubilization fractions were highly redundant with those in the previous

  10. Normative Data for Bone Mass in Healthy Term Infants from Birth to 1 Year of Age

    Directory of Open Access Journals (Sweden)

    Sina Gallo

    2012-01-01

    Full Text Available For over 2 decades, dual-energy X-ray absorptiometry (DXA has been the gold standard for estimating bone mineral density (BMD and facture risk in adults. More recently DXA has been used to evaluate BMD in pediatrics. However, BMD is usually assessed against reference data for which none currently exists in infancy. A prospective study was conducted to assess bone mass of term infants (37 to 42 weeks of gestation, weight appropriate for gestational age, and born to healthy mothers. The group consisted of 33 boys and 26 girls recruited from the Winnipeg Health Sciences Center (Manitoba, Canada. Whole body (WB as well as regional sites of the lumbar spine (LS 1–4 and femur was measured using DXA (QDR 4500A, Hologic Inc. providing bone mineral content (BMC for all sites and BMD for spine. During the year, WB BMC increased by 200% (76.0±14.2 versus 227.0±29.7 g, spine BMC by 130% (2.35±0.42 versus 5.37±1.02 g, and femur BMC by 190% (2.94±0.54 versus 8.50±1.84 g. Spine BMD increased by 14% (0.266±0.044 versus 0.304±0.044 g/cm2 during the year. This data, representing the accretion of bone mass during the first year of life, is based on a representative sample of infants and will aid in the interpretation of diagnostic DXA scans by researchers and health professionals.

  11. Binary black hole coalescence in the extreme-mass-ratio limit: testing and improving the effective-one-body multipolar waveform

    CERN Document Server

    Bernuzzi, Sebastiano; Zenginoglu, Anil

    2010-01-01

    We discuss the properties of the effective-one-body (EOB) multipolar gravitational waveform emitted by nonspinning black-hole binaries of masses $\\mu$ and $M$ in the extreme-mass-ratio limit, $\\mu/M=\

  12. Lasofoxifene (CP-336,156) protects against the age-related changes in bone mass, bone strength, and total serum cholesterol in intact aged male rats.

    Science.gov (United States)

    Ke, H Z; Qi, H; Chidsey-Frink, K L; Crawford, D T; Thompson, D D

    2001-04-01

    The purpose of this study was to evaluate if long-term (6 months) treatment with lasofoxifene (LAS), a new selective estrogen receptor modulator (SERM), can protect against age-related changes in bone mass and bone strength in intact aged male rats. Sprague-Dawley male rats at 15 months of age were treated (daily oral gavage) with either vehicle (n = 12) or LAS at 0.01 mg/kg per day (n = 12) or 0.1 mg/kg per day (n = 11) for 6 months. A group of 15 rats was necropsied at 15 months of age and served as basal controls. No significant change was found in body weight between basal and vehicle controls. However, an age-related increase in fat body mass (+42%) and decrease in lean body mass (-8.5%) was observed in controls. Compared with vehicle controls, LAS at both doses significantly decreased body weight and fat body mass but did not affect lean body mass. No significant difference was found in prostate wet weight among all groups. Total serum cholesterol was significantly decreased in all LAS-treated rats compared with both the basal and the vehicle controls. Both doses of LAS treatment completely prevented the age-related increase in serum osteocalcin. Peripheral quantitative computerized tomography (pQCT) analysis at the distal femoral metaphysis indicated that the age-related decrease in total density, trabecular density, and cortical thickness was completely prevented by treatment with LAS at 0.01 mg/kg per day or 0.1 mg/kg per day. Histomorphometric analysis of proximal tibial cancellous bone showed an age-related decrease in trabecular bone volume (TBV; -46%), trabecular number (Tb.N), wall thickness (W.Th), mineral apposition rate, and bone formation rate-tissue area referent. Moreover, an age-related increase in trabecular separation (Tb.Sp) and eroded surface was observed. LAS at 0.01 mg/kg per day or 0.1 mg/kg per day completely prevented these age-related changes in bone mass, bone structure, and bone turnover. Similarly, the age-related decrease in TBV

  13. Cognitive function in relation with bone mass and nutrition: cross-sectional association in postmenopausal women

    Directory of Open Access Journals (Sweden)

    Brownbill Rhonda A

    2004-05-01

    Full Text Available Abstract Background It has been suggested that bone loss and cognitive decline are co-occurring conditions, possibly due to their relationship with estrogen. Cognitive decline has been associated with various nutritional deficiencies as well. The purpose of this study was to determine if cognitive function is related to bone mineral density of various skeletal sites as well as to various dietary components. Methods Cross-sectional study with 97 healthy, Caucasian, postmenopausal women (59.4–85.0 years enrolled in a larger longitudinal study, investigating the effects of sodium on bone mass. The subjects were divided into two groups based on cognition scores. Group 1 represented lower and Group 2 higher scores on cognitive function. Bone mineral density from the whole body, lumbar spine, femur and forearm were measured with the Lunar DPX-MD instrument. Anthropometry was measured by standard methods. Cognition was assessed using the Mini Mental State Examination. Cumulative (over 2 years dietary intake from 3-day records was analyzed by Food Processor® (ESHA Research, Salem, OR and cumulative physical activity was assessed using Allied Dunbar National Fitness Survey for older adults. Results Subjects' cognition scores ranged from 22–30 (normal, 27–30, indicating all subjects had either mild or no cognitive impairment. Multiple Analysis of Covariance adjusted for age, height, weight, physical activity, alcohol, calcium, sodium and energy intake, showed a statistically significant association between cognition and bone mineral density of all measurable sites (η2 = 0.21, P 2 = 0.07, P = 0.050. Group 2 did have a significantly higher potassium intake (P = 0.023. In multiple regression, saturated fat had a significant negative relationship with cognitive function. Conclusions It appears mild degree of cognitive impairment may be a marker for lower bone mineral density as well as for a diet lower in carbohydrate and potassium intake, and higher

  14. Lef1 haploinsufficient mice display a low turnover and low bone mass phenotype in a gender- and age-specific manner.

    Directory of Open Access Journals (Sweden)

    Tommy Noh

    Full Text Available We investigated the role of Lef1, one of the four transcription factors that transmit Wnt signaling to the genome, in the regulation of bone mass. Microcomputed tomographic analysis of 13- and 17-week-old mice revealed significantly reduced trabecular bone mass in Lef1(+/- females compared to littermate wild-type females. This was attributable to decreased osteoblast activity and bone formation as indicated by histomorphometric analysis of bone remodeling. In contrast to females, bone mass was unaffected by Lef1 haploinsufficiency in males. Similarly, females were substantially more responsive than males to haploinsufficiency in Gsk3beta, a negative regulator of the Wnt pathway, displaying in this case a high bone mass phenotype. Lef1 haploinsufficiency also led to low bone mass in males lacking functional androgen receptor (AR (tfm mutants. The protective skeletal effect of AR against Wnt-related low bone mass is not necessarily a result of direct interaction between the AR and Wnt signaling pathways, because Lef1(+/- female mice had normal bone mass at the age of 34 weeks. Thus, our results indicate an age- and gender-dependent role for Lef1 in regulating bone formation and bone mass in vivo. The resistance to Lef1 haploinsufficiency in males with active AR and in old females could be due to the reduced bone turnover in these mice.

  15. Quantification of bone mass gain in response to the application of biphasic bioceramics and platelet concentrate in critical-size bone defects.

    Science.gov (United States)

    Lobo, Sonja Ellen; Wykrota, Francisco Henrique Lanna; Oliveira, Ana Carolina Marques Barbosa; Kerkis, Irina; Mahecha, Germán Bohorquez; Alves, Humberto José

    2009-05-01

    Biphasic bioceramics have been widely indicated for bone reconstruction; however, the real gain in bone mass due to the presence of such biomaterials has not been established yet nor the advantages of its association with platelet concentrate. This study aims at quantifying the volume of bone matrix, osteoblasts, osteocytes, blood vessels and adipose tissue after the application of a biphasic bioceramics composed of 65% hydroxyapatite and 35% beta-tricalcium phosphate. Critical-size bone defects were produced in rabbit femora and reconstructed with bioceramics only, with bioceramics combined with platelet concentrate, with platelet concentrate alone, and with no treatment (blood clot). The quantitative evaluation was performed on histological sections using histomorphometry. Our data provide original evidence that consolidates the indication of bioceramics for clinical bone loss reconstruction. The application of biphasic bioceramics alone led to major bone mass gain and was followed by its association with platelet concentrate. On the other hand, platelet concentrate can contribute to the augmentation and maintenance of the adipose tissue, representing a new field for future applications in plastic surgery.

  16. Sedentary behaviours and its association with bone mass in adolescents: the HELENA cross-sectional study

    Directory of Open Access Journals (Sweden)

    Gracia-Marco Luis

    2012-11-01

    Full Text Available Abstract Background We aimed to examine whether time spent on different sedentary behaviours is associated with bone mineral content (BMC in adolescents, after controlling for relevant confounders such as lean mass and objectively measured physical activity (PA, and if so, whether extra-curricular participation in osteogenic sports could have a role in this association. Methods Participants were 359 Spanish adolescents (12.5-17.5 yr, 178 boys, from the HELENA-CSS (2006–07. Relationships of sedentary behaviours with bone variables were analysed by linear regression. The prevalence of low BMC (at least 1SD below the mean and time spent on sedentary behaviours according to extracurricular sport participation was analysed by Chi-square tests. Results In boys, the use of internet for non-study was negatively associated with whole body BMC after adjustment for lean mass and moderate to vigorous PA (MVPA. In girls, the time spent studying was negatively associated with femoral neck BMC. Additional adjustment for lean mass slightly reduced the negative association between time spent studying and femoral neck BMC. The additional adjustment for MVPA did not change the results at this site. The percentage of girls having low femoral neck BMC was significantly smaller in those participating in osteogenic sports (≥ 3 h/week than in the rest, independently of the cut-off selected for the time spent studying. Conclusions The use of internet for non-study (in boys and the time spent studying (in girls are negatively associated with whole body and femoral neck BMC, respectively. In addition, at least 3 h/week of extra-curricular osteogenic sports may help to counteract the negative association of time spent studying on bone health in girls.

  17. The impact of mass segregation and star-formation on the rates of gravitational-wave sources from extreme mass ratio inspirals

    CERN Document Server

    Aharon, Danor

    2016-01-01

    Compact stellar objects inspiralling into massive black holes (MBHs) in galactic nuclei are some of the most promising gravitational wave (GWs) sources for next generation GW-detectors. The rates of such extreme mass ratio inspirals (EMRIs) depend on the dynamics and distribution of compact objects around the MBH. Here we study the impact of mass-segregation processes on EMRI rates. In particular, we provide the expected mass function of EMRIs, given an initial mass function of stellar BHs (SBHs), and relate it to the mass-dependent detection rate of EMRIs. We then consider the role of star formation on the distribution of compact objects and its implication on EMRI rates. We find that the existence of a wide spectrum of SBH masses lead to the overall increase of EMRI rates, and to high rates of the EMRIs from the most-massive SBHs. However, it also leads to a relative quenching of EMRI rates from lower-mass SBHs, and together produces a steep dependence of the EMRI mass function on the highest-mass SBHs. Sta...

  18. Relationship of Fibroblast Growth Factor 23 (FGF-23) Serum Levels With Low Bone Mass in Postmenopausal Women.

    Science.gov (United States)

    Shen, Jun; Fu, Shiping; Song, Yuan

    2017-05-02

    The aim of this study was to determine the relationship between serum fibroblast growth factor-23 (FGF-23) level and bone mass in postmenopausal women. A total of 60 premenopausal, 60 early postmenopausal, and 60 late postmenopausal women were investigated by the measurement of bone mineral densities (BMDs) at lumbar spine and proximal femur by DXA, together with serum concentrations of Ca, P, 25 (OH) D3 , OC, iPTH, CTX-I, PINP, and FGF-23. The levels of FGF-23 and PINP in early postmenopausal group were significantly higher than that in the premenopausal or the late postmenopausal groups, their changing patterns were different form 25(OH)D3, iPTH, IGF, CTX-I, and OC. According to the AUCs in the ROC analysis, we found that serum FGF-23 level was associated with the highest validity as compared to the other bone metabolism factors. Further study indicated the significant negative relationships between serum FGF-23 level and lumbar spine/proximal femur BMDs in postmenopausal women. After detection of the sensitivity and specificity of serum FGF- 23 for the low bone mass at different T-score (SD) lumbar spine/proximal femur BMDs, we found that serum FGF-23 level may be a reliable marker for low bone mass in postmenopausal women. The performance of FGF-23 in the differential diagnosis low bone mass from healthy participants indicated that FGF-23 has the capacity to differentiate the women with low bone mass from the normal ones. Our study indicated that serum FGF-23 level could be served as the utility in the early detection of women with low bone mass. J. Cell. Biochem. 9999: 1-6, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Selective deletion of the membrane-bound colony stimulating factor 1 isoform leads to high bone mass but does not protect against estrogen-deficiency bone loss.

    Science.gov (United States)

    Yao, Gang-Qing; Wu, Jian-Jun; Troiano, Nancy; Zhu, Mei-Ling; Xiao, Xiao-Yan; Insogna, Karl

    2012-07-01

    To better define the biologic function of membrane-bound CSF1 (mCSF1) in vivo, we have generated mCSF1 knockout (k/o) mice. Spinal bone density (BMD) was 15.9% higher in k/o mice compared to wild-type (wt) controls (P bone marrow isolated from mCSF1 k/o mice was reduced compared to wt marrow. There were no defects in osteoblast number or function suggesting that the basis for the high bone mass phenotype was reduced resorption. In addition to a skeletal phenotype, k/o mice had significantly elevated serum triglyceride levels (123 ± 7 vs. 88 ± 3.2 mg/dl; k/o vs. wt, P bone loss following ovariectomy (OVX). OVX induced a significant fourfold increase in the expression of the soluble CSF1 isoform (sCSF1) in the bones of wt mice while expression of mCSF1 was unchanged. These findings indicate that mCSF1 is essential for normal bone remodeling since, in its absence, BMD is increased. Membrane-bound CSF1 does not appear to be required for estrogen-deficiency bone loss while in contrast; our data suggest that sCSF1 could play a key role in this pathologic process. The reasons why mCSF1 k/o mice have hypertriglyceridemia are currently under study.

  20. Operative Risk for Major Lung Resection Increases at Extremes of Body Mass Index

    Science.gov (United States)

    Williams, Trevor; Gulack, Brian C.; Kim, Sunghee; Fernandez, Felix G.; Ferguson, Mark K.

    2016-01-01

    Background Although body mass index (BMI) has been used in risk stratification for lung resection, many models only take obesity into account. Recent studies have demonstrated that underweight patients also experience increased postoperative complications. We explored the relationship of extremes of BMI to outcomes after lung resection for non-small cell cancer. Methods Patients in the Society of Thoracic Surgeons General Thoracic Surgery Database (2009 to 2014) undergoing elective lung resection for cancer were evaluated. Multivariable logistic regression was used to adjust for potential confounders including functional status and spirometry. Results We evaluated 41,446 patients (median 68 years of age; 53% female) grouped by BMI: underweight (<18.5 kg/m2; 3.0%), normal (18.5 to 24.9 kg/m2; 33.5%), overweight (25 to 29.9 kg/m2; 35.4%), obese I (30 to 34.9 kg/m2; 18.1%), obese II (35 to 39.9 kg/m2; 6.4%), and obese III (≥40 kg/m2; 3.6%). Pulmonary complication rates were higher in underweight and obese III patients compared to normal BMI patients (p < 0.001). On multivariable analysis, compared to patients with normal BMI, being underweight was associated with an increased risk of pulmonary complications (adjusted odds ratio [OR]: 1.41, 95% confidence interval [CI]: 1.16 to 1.70) and any postoperative event (adjusted OR: 1.44, 95% CI: 1.26 to 1.64). Obese III patients had an increased risk of any major postoperative complication (adjusted OR: 1.18, 95% CI: 1.02 to 1.36). Overweight and obese class I to II patients had a lower risk of pulmonary complications and any postoperative event. Conclusions BMI is associated with postoperative complications after lung resection for cancer. Being underweight or severely overweight is associated with an increased risk of complications, whereas being overweight or moderately obese appears to have a protective effect. PMID:27476820

  1. Higher doses of bisphosphonates further improve bone mass, architecture, and strength but not the tissue material properties in aged rats.

    Science.gov (United States)

    Shahnazari, Mohammad; Yao, Wei; Dai, WeiWei; Wang, Bob; Ionova-Martin, Sophi S; Ritchie, Robert O; Heeren, Daniel; Burghardt, Andrew J; Nicolella, Daniel P; Kimiecik, Michael G; Lane, Nancy E

    2010-05-01

    We report the results of a series of experiments designed to determine the effects of ibandronate (Ibn) and risedronate (Ris) on a number of bone quality parameters in aged osteopenic rats to explain how bone material and bone mass may be affected by the dose of bisphosphonates (BP) and contribute to their anti-fracture efficacy. Eighteen-month old female rats underwent either ovariectomy or sham surgery. The ovariectomized (OVX) groups were left untreated for 2 months to develop osteopenia. Treatments started at 20 months of age as follows: sham and OVX control (treated with saline), OVX + risedronate 30 and 90 (30 or 90 microg/kg/dose), and OVX + ibandronate 30 and 90 (30 or 90 microg/kg/dose). The treatments were given monthly for 4 months by subcutaneous injection. At sacrifice at 24 months of age the 4th lumbar vertebra was used for microCT scans (bone mass, architecture, and degree of mineralization of bone, DMB) and histomorphometry, and the 6th lumbar vertebra, tibia, and femur were collected for biomechanical testing to determine bone structural and material strength, cortical fracture toughness, and tissue elastic modulus. The compression testing of the vertebral bodies (LVB6) was simulated using finite-element analysis (FEA) to also estimate the bone structural stiffness. Both Ibn and Ris dose-dependently increased bone mass and improved vertebral bone microarchitecture and mechanical properties compared to OVX control. Estimates of vertebral maximum stress from FEA were correlated with vertebral maximum load (r=0.5, pbone bending modulus and cortical strength increased compared to OVX with both BP but no dose-dependent effect was observed. DMB and elastic modulus of trabecular bone were improved with Ibn 30 compared to OVX but were not affected in other BP-treated groups. DMB of tibial cortical bone showed no change with BP treatments. The fracture toughness examined in midshaft femurs did not change with BP even with the higher doses. In summary, the

  2. Sclerostin antibody treatment causes greater alveolar crest height and bone mass in an ovariectomized rat model of localized periodontitis.

    Science.gov (United States)

    Chen, Hui; Xu, Xinchen; Liu, Min; Zhang, Wen; Ke, Hua-zhu; Qin, An; Tang, Tingting; Lu, Eryi

    2015-07-01

    Periodontitis and osteoporosis are bone destructive diseases with a high prevalence in the adult population. The concomitant presence of osteoporosis may be a risk factor of progression of periodontal destruction. We studied the effect of sclerostin-neutralizing monoclonal antibody (Scl-Ab) on alveolar bone endpoints in an ovariectomized (OVX) rat model of induced experimental periodontitis. Sixty female, 4-month-old Sprague-Dawley rats underwent sham operation or bilateral OVX and were left untreated for 2 months. Experimental periodontitis (ligature) was established by placing silk sutures subgingival to the right maxillary first and second molar teeth for 4 weeks, and feeding the rats food and high-sugar drinking water during this period. Thereafter, ligatures were removed and 25mg/kg vehicle or Scl-Ab was administered subcutaneously twice weekly for 6 weeks. Rats were randomized into four groups: (1) Control (Sham+Vehicle), (2) Sham+Ligature+Vehicle, (3) OVX+Ligature+Vehicle, and (4) OVX + Ligature + Scl-Ab. Terminal blood and right maxilla specimens were collected for analyses. Group 3 rats showed lower bone volume fraction (BVF) of alveolar bone with higher bone resorption and lower bone formation than Group 2 rats. Group 4 rats had higher alveolar crest height, as assessed by linear distance of cementoenamel junction to the alveolar bone crest and greater alveolar bone mass using Micro CT, than Group 3 rats. Significantly higher values of mineral apposition rate (MAR) and mineralizing surface/bone surface (MS/BS) were also observed in Group 4 rats by analyzing polychrome sequential labeling data. Increased serum osteocalcin and osteoprotegerin, and deceased serum tartrate-resistant acid phosphatase and CTx-1 illustrate the ability of Scl-Ab to increase alveolar bone mass by enhancing bone formation and decreasing bone resorption in an animal model of estrogen deficiency osteopenia plus periodontitis. Scl-Ab could be a potential bone anabolic agent for

  3. The presence of intermediate-mass black holes in globular clusters and its connection with extreme horizontal branch stars

    CERN Document Server

    Miocchi, P

    2007-01-01

    By means of a multimass isotropic and spherical model including self-consistently a central intermediate-mass black hole (IMBH), the influence of this object on the morphological and physical properties of globular clusters is investigated in this paper. Confirming recent numerical studies, it is found that a cluster (with mass M) hosting an IMBH (with mass M_BH) shows, outside the black hole gravitational influence region, a core-like profile resembling a King profile with concentration cM. The mass range estimate 12s - 4.8 90 percent). In particular, the presence of a central IMBH could explain why extreme HB stars are observed in M13 and NGC 6388, but not in M3 and 47 Tuc where this object is likely absent according to our analysis.

  4. Identifying neutrino mass hierarchy at extremely small theta13 through earth matter effects in a supernova signal.

    Science.gov (United States)

    Dasgupta, Basudeb; Dighe, Amol; Mirizzi, Alessandro

    2008-10-24

    Collective neutrino flavor transformations deep inside a supernova are sensitive to the neutrino mass hierarchy even at extremely small values of theta_(13). Exploiting this effect, we show that comparison of the antineutrino signals from a galactic supernova in two megaton class water Cherenkov detectors, one of which is shadowed by Earth, will enable us to distinguish between the hierarchies if sin(2)theta_(13) < or approximately 10(-5), where long baseline neutrino experiments would be ineffectual.

  5. Systematic review of raloxifene in postmenopausal Japanese women with osteoporosis or low bone mass (osteopenia

    Directory of Open Access Journals (Sweden)

    Fujiwara S

    2014-11-01

    Full Text Available Saeko Fujiwara,1 Etsuro Hamaya,2 Masayo Sato,2 Peita Graham-Clarke,3 Jennifer A Flynn,2 Russel Burge41Hiroshima Atomic Bomb Casualty Council, Hiroshima, Japan; 2Lilly Research Laboratories Japan, Eli Lilly Japan K.K., Kobe, Japan; 3Global Health Outcomes, Eli Lilly Australia, Sydney, NSW, Australia; 4Global Health Outcomes, Eli Lilly and Company, Indianapolis, IN, USAPurpose: To systematically review the literature describing the efficacy, effectiveness, and safety of raloxifene for postmenopausal Japanese women with osteoporosis or low bone mass (osteopenia.Materials and methods: Medline via PubMed and Embase was systematically searched using prespecified terms. Retrieved publications were screened and included if they described randomized controlled trials or observational studies of postmenopausal Japanese women with osteoporosis or osteopenia treated with raloxifene and reported one or more outcome measures (change in bone mineral density [BMD]; fracture incidence; change in bone-turnover markers, hip structural geometry, or blood–lipid profile; occurrence of adverse events; and change in quality of life or pain. Excluded publications were case studies, editorials, letters to the editor, narrative reviews, or publications from non-peer-reviewed journals; multidrug, multicountry, or multidisease studies with no drug-, country-, or disease-level analysis; or studies of participants on dialysis.Results: Of the 292 publications retrieved, 15 publications (seven randomized controlled trials, eight observational studies were included for review. Overall findings were statistically significant increases in BMD of the lumbar spine (nine publications, but not the hip region (eight publications, a low incidence of vertebral fracture (three publications, decreases in markers of bone turnover (eleven publications, improved hip structural geometry (two publications, improved blood–lipid profiles (five publications, a low incidence of hot flushes

  6. The structure of long tubular bones fractures of lower extremity by the data of the regional bureau of forensic-medical examination

    Directory of Open Access Journals (Sweden)

    Savka I.H.

    2013-10-01

    Full Text Available The main purpose of the research is carrying out forensic-medical analysis of cases from expert’s practice with fractures of the long bones based on the findings of the Regional Bureau of Forensic-Medical Examination over 2009-2012 years period. The research has been carried out using methods of statistical and comparative analysis. Their distribution by gender, age, localization, character and type of external influence, the conditions of their occurrence and participation of other persons has been outlined. Fractures of lower extremity bones make up from 15,8 to 22,5% of all the cases of mechanical trauma with lethal outcomes. Therewith male persons suffer more often from injury of the left extremity at different day time and season. The principal mechanism of their origin is injury resulting from road accidents in the countryside with the participation of other persons.

  7. The National Osteoporosis Foundation's position statement on peak bone mass development and lifestyle factors: a systematic review and implementation recommendations.

    Science.gov (United States)

    Weaver, C M; Gordon, C M; Janz, K F; Kalkwarf, H J; Lappe, J M; Lewis, R; O'Karma, M; Wallace, T C; Zemel, B S

    2016-04-01

    Lifestyle choices influence 20-40 % of adult peak bone mass. Therefore, optimization of lifestyle factors known to influence peak bone mass and strength is an important strategy aimed at reducing risk of osteoporosis or low bone mass later in life. The National Osteoporosis Foundation has issued this scientific statement to provide evidence-based guidance and a national implementation strategy for the purpose of helping individuals achieve maximal peak bone mass early in life. In this scientific statement, we (1) report the results of an evidence-based review of the literature since 2000 on factors that influence achieving the full genetic potential for skeletal mass; (2) recommend lifestyle choices that promote maximal bone health throughout the lifespan; (3) outline a research agenda to address current gaps; and (4) identify implementation strategies. We conducted a systematic review of the role of individual nutrients, food patterns, special issues, contraceptives, and physical activity on bone mass and strength development in youth. An evidence grading system was applied to describe the strength of available evidence on these individual modifiable lifestyle factors that may (or may not) influence the development of peak bone mass (Table 1). A summary of the grades for each of these factors is given below. We describe the underpinning biology of these relationships as well as other factors for which a systematic review approach was not possible. Articles published since 2000, all of which followed the report by Heaney et al. [1] published in that year, were considered for this scientific statement. This current review is a systematic update of the previous review conducted by the National Osteoporosis Foundation [1]. [Table: see text] Considering the evidence-based literature review, we recommend lifestyle choices that promote maximal bone health from childhood through young to late adolescence and outline a research agenda to address current gaps in knowledge

  8. Clinical and hormonal variables related to bone mass loss in anorexia nervosa patients.

    Science.gov (United States)

    Fernández-Soto, María Luisa; González-Jiménez, Amalia; Chamorro-Fernández, Marta; Leyva-Martínez, Socorro

    2013-01-01

    A better understanding of the prognostic factors of low bone mass in anorexia nervosa (AN) and development of effective therapeutic strategies is critical. In order to determine which clinical, biochemical, and/or hormonal parameters could be related to bone mineral density (BMD), 47 female AN patients were classified according to the WHO osteoporosis criteria at lumbar spine (LS). This was a cross-sectional study of 16 AN women with osteoporosis criteria and 31without. Control group was 25 healthy, normal-weight, age-matched women. We assessed BMD using dual-energy X-ray absorptiometry at the LS and body composition. We measured serum fasting cortisol, estradiol, insulin-like growth factor-1 (IGF-1), leptin, sex hormone-binding globulin, albumin and retinol binding protein levels. The prevalence of osteoporosis was 34% and osteopenia 19% at the LS. The AN group with osteoporosis had lower IGF-1 and estradiol levels (both p<0.001), lower serum leptin (p<0.02), and higher cortisolemia (p<0.03) levels compared with AN group without osteoporosis. The BMD and T-score at LS was inversely related to the duration of amenorrhea (p<0.02) and directly related to body mass index (BMI, p<0.002), total fat mass (p<0.03), serum IGF-1 (p<0.01), and estradiol levels (p<0.001) in AN patients. We conclude that AN women with a significant BMD loss have a high risk of developing osteoporosis. A low BMD is a consequence of hormonal alterations which include hypoestrogenism, hypoleptinemia, hypercortisolism, and decreases in IGF-1 levels, as well as a low BMI and fat mass.

  9. OPTIMIZING BONE MASS AND STRENGTH: THE ROLE OF PHYSICAL ACTIVITY AND NUTRITION DURING GROWTH (MEDICINE & SPORT SCIENCE, VOL 51

    Directory of Open Access Journals (Sweden)

    R. M. Daly

    2007-09-01

    Full Text Available DESCRIPTION This volume describes and discusses the maturation of bone in children and adolescents. The focus is on the role of physical activity for optimizing this process. PURPOSE To provide an up to date review of the factors that influence the development of bone health during childhood and adolescence. AUDIENCE Exercise specialists, pediatricians, nutritionists, biomedical researchers, sports medics and any public health professional will find this book very helpful when dealing with optimizing bone development and/or maintaining bone health. FEATURES The featured subjects are: Osteoporosis: A Pediatric Concern?; The Biomechanical Basis of Bone Strength Development during Growth; The Effect of Exercise on Bone Mass and Structural Geometry during Growth; Evidence for an Interaction between Exercise and Nutrition for Improved Bone Health during Growth; Gene- Environment Interactions in the Skeletal Response to Nutrition and Exercise during Growth; The Effect of Energy Balance on Endocrine Function and Bone Health in Youth; Risk Factors for Fractures in Normally Active Children and Adolescents; Does Exercise during Growth Prevent Fractures in Later Life?; Lessons Learned from School-Based Skeletal Loading Intervention Trials: Putting Research into Practice. ASSESSMENT The editors have assembled the 51st' volume of Medicine and Sports Science as a necessary reading for exercise specialists, pediatricians, nutritionists, and/or any public health professionals interested in understanding and improving the health of bone in children and adults. The book provides an excellent source of recent information on the subject

  10. Visualizing fossilization using laser ablation-inductively coupled plasma-mass spectrometry maps of trace elements in Late Cretaceous bones

    Science.gov (United States)

    Koenig, A.E.; Rogers, R.R.; Trueman, C.N.

    2009-01-01

    Elemental maps generated by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) provide a previously unavailable high-resolution visualization of the complex physicochemical conditions operating within individual bones during the early stages of diagenesis and fossilization. A selection of LA-ICP-MS maps of bones collected from the Late Cretaceous of Montana (United States) and Madagascar graphically illustrate diverse paths to recrystallization, and reveal unique insights into geochemical aspects of taphonomic history. Some bones show distinct gradients in concentrations of rare earth elements and uranium, with highest concentrations at external bone margins. Others exhibit more intricate patterns of trace element uptake related to bone histology and its control on the flow paths of pore waters. Patterns of element uptake as revealed by LA-ICP-MS maps can be used to guide sampling strategies, and call into question previous studies that hinge upon localized bulk samples of fossilized bone tissue. LA-ICP-MS maps also allow for comparison of recrystallization rates among fossil bones, and afford a novel approach to identifying bones or regions of bones potentially suitable for extracting intact biogeochemical signals. ?? 2009 Geological Society of America.

  11. Bone mineral density, body mass index and cigarette smoking among Iranian women: implications for prevention

    Directory of Open Access Journals (Sweden)

    Nguyen Nguyen D

    2005-06-01

    Full Text Available Abstract Background While risk factors of osteoporosis in Western populations have been extensively documented, such a profile has not been well studied in Caucasians of non-European origin. This study was designed to estimate the modifiable distribution and determinants of bone mineral density (BMD among Iranian women in Australia. Methods Ninety women aged 35 years and older completed a questionnaire on socio-demographic and lifestyle factors. BMD was measured at the lumbar spine (LS and femoral neck (FN using DXA (GE Lunar, WI, USA, and was expressed in g/cm2 as well as T-score. Results In multiple regression analysis, advancing age, lower body mass index (BMI, and smoking were independently associated with LS and FN BMD, with the 3 factors collectively accounting for 30% and 38% variance of LS and FN BMD, respectively. LS and FN BMD in smokers was 8% lower than that in non-smokers. Further analysis of interaction between BMI and smoking revealed that the effect of smoking was only observed in the obese group (p = 0.029 for LSBMD and p = 0.007 for FNBMD, but not in the overweight and normal groups. Using T-scores from two bone sites the prevalence of osteoporosis (T-scores ≤ -2.5 was 3.8% and 26.3% in pre-and post-menopausal women, respectively. Among current smokers, the prevalence was higher (31.3% than that among ex-smokers (28.6% and non-smokers (7.5%. Conclusion These data, for the first time, indicate that apart from advancing age and lower body mass index, cigarette smoking is an important modifiable determinant of bone mineral density in these Caucasians of non-European origin.

  12. Mass spectrometric monitoring of Sr-enriched bone cements--from in vitro to in vivo.

    Science.gov (United States)

    Rohnke, Marcus; Henss, Anja; Kokesch-Himmelreich, Julia; Schumacher, Matthias; Ray, Seemun; Alt, Volker; Gelinsky, Michael; Janek, Juergen

    2013-11-01

    Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a well-established technique in materials science, but is now increasingly applied also in the life sciences. Here, we demonstrate the potential of this analytical technique for use in the development of new bone implant materials. We tracked strontium-enriched calcium phosphate cements, which were developed for the treatment of osteoporotic bone, from in vitro to in vivo. Essentially, the spatial distribution of strontium in two different types of strontium-modified calcium phosphate cements is analysed by SIMS depth profiling. To gain information about the strontium release kinetics, the cements were immersed for 3, 7, 14 and 21 days in α-MEM and tris(hydroxymethyl)-aminomethane solution and analysed afterwards by ToF-SIMS depth profiling. For cements stored in α-MEM solution an inhibited strontium release was observed. By using principal component analysis to evaluate TOF-SIMS surface spectra, we are able to prove the adsorption of proteins on the cement surface, which inhibit the release kinetics. Cell experiments with human osteoblast-like cells cultured on the strontium-modified cements and subsequent mass spectrometric analysis of the mineralised extracellular matrix (mECM) prove clearly that strontium is incorporated into the mECM of the osteoblast-like cells. Finally, in an animal experiment, the strontium-doped cements are implanted into the femur of osteoporotic rats. After 6 weeks, only a slight release of strontium was found in the vicinity of the implant material. By using ToF-SIMS, it is proven that strontium is localised in regions of newly formed bone but also within the pre-existing tissue.

  13. ATP6v0d2 Deficiency Increases Bone Mass, but Does Not Influence Ovariectomy-Induced Bone Loss

    Science.gov (United States)

    Kim, Taesoo; Ha, Hyunil; Kim, Nacksung; Park, Eui-Soon; Rho, Jaerang; Kim, Eun Cheol; Lorenzo, Joseph; Choi, Yongwon; Lee, Seoung Hoon

    2010-01-01

    Bone homeostasis is maintained through the balanced action of bone-forming osteoblasts and bone-resorbing osteoclasts. Under pathological conditions or with age, excessive bone loss is often observed due to increased bone resorption. Since osteoclasts are the primary cells in the body that can resorb bone, molecular understanding of osteoclast fate has important clinical implications. Over the past twenty years, many molecular players that govern osteoclast differentiation during normal development have been identified. However, whether the same molecules regulate bone loss occurring under pathological conditions remains largely unknown. We report here that although ATP6v0d2-deficient (ATP6v0d2 KO) mice exhibit an osteopetrotic phenotype due to inefficient osteoclast maturation, this deficiency fails to protect mice from ovariectomy (OVX)-induced bone loss, a model for post-menopause-associated osteoporosis. Moreover, we show that an OVX-induced increase in the number of colony forming unit-granulocyte/macrophage (CFU-GM) in bone marrow cells and subsequent osteoclast formation in vitro was not affected in the absence of ATP6v0d2. However, even after OVX, formation of large osteoclasts (> 100 μm in diameter) with actin rings was still reduced in the absence of ATP6v0d2. Taken together, these findings suggest that the critical role of ATP6v0d2 may be limited to the control of bone homeostasis under normal development, and that OVX-induced bone loss is likely to be governed mostly by the increase in osteoclast precursors rather than increased efficiency of osteoclast maturation. PMID:21040703

  14. Lycopene treatment against loss of bone mass, microarchitecture and strength in relation to regulatory mechanisms in a postmenopausal osteoporosis model.

    Science.gov (United States)

    Ardawi, Mohammed-Salleh M; Badawoud, Mohammed H; Hassan, Sherif M; Rouzi, Abdulrahim A; Ardawi, Jumanah M S; AlNosani, Nouf M; Qari, Mohammed H; Mousa, Shaker A

    2016-02-01

    Lycopene supplementation decreases oxidative stress and exhibits beneficial effects on bone health, but the mechanisms through which it alters bone metabolism in vivo remain unclear. The present study aims to evaluate the effects of lycopene treatment on postmenopausal osteoporosis. Six-month-old female Wistar rats (n=264) were sham-operated (SHAM) or ovariectomized (OVX). The SHAM group received oral vehicle only and the OVX rats were randomized into five groups receiving oral daily lycopene treatment (mg/kg body weight per day): 0 OVX (control), 15 OVX, 30 OVX, and 45 OVX, and one group receiving alendronate (ALN) (2μg/kg body weight per day), for 12weeks. Bone densitometry measurements, bone turnover markers, biomechanical testing, and histomorphometric analysis were conducted. Micro computed tomography was also used to evaluate changes in microarchitecture. Lycopene treatment suppressed the OVX-induced increase in bone turnover, as indicated by changes in biomarkers of bone metabolism: serum osteocalcin (s-OC), serum N-terminal propeptide of type 1 collagen (s-PINP), serum crosslinked carboxyterminal telopeptides (s-CTX-1), and urinary deoxypyridinoline (u-DPD). Significant improvement in OVX-induced loss of bone mass, bone strength, and microarchitectural deterioration was observed in lycopene-treated OVX animals. These effects were observed mainly at sites rich in trabecular bone, with less effect in cortical bone. Lycopene treatment down-regulated osteoclast differentiation concurrent with up-regulating osteoblast together with glutathione peroxidase (GPx) catalase (CAT) and superoxide dismutase (SOD) activities. These findings demonstrate that lycopene treatment in OVX rats primarily suppressed bone turnover to restore bone strength and microarchitecture.

  15. Effect of long-term growth hormone treatment on bone mass and bone metabolism in growth hormone-deficient men

    NARCIS (Netherlands)

    Bravenboer, N; Holzmann, PJ; ter Maaten, JC; Stuurman, LM; Roos, JC; Lips, P

    2005-01-01

    Long-term GH treatment in GH-deficient men resulted in a continuous increase in bone turnover as shown by histomorphometry. BMD continuously increased in all regions of interest, but more in the regions with predominantly cortical bone. Introduction: Adults with growth hormone (GH) deficiency have

  16. Extreme deformations and clusterization at high spin in the A ~ 40 mass region

    Science.gov (United States)

    Ray, Debisree; Afanasjev, Anatoli

    2015-10-01

    Recent revival of the interest to the study of superdeformation and clusterization in light nuclei has motivated us to undertake the study of extreme deformations in the A ~ 32 - 50 N ~ Z nuclei. Unfortunately, at spin zero the predicted structures with extreme deformation are located at high excitation energies which prevents their experimental observation. On the other hand, the rotation brings such structures closer to the yrast line and, in principle, makes their observation possible with future generation of facilities such as GRETA. Thus, the systematic study of the extremely deformed structures and clusterization has been performed in the framework of cranked relativistic mean field theory. The major features of such structures, the spins at which they become yrast and the possiblities of their experimental observation will be discussed in this presentation. This work has been supported by the U.S. Department of Energy under the Grant DE-FG02-07ER41459.

  17. DLK1 is a novel regulator of bone mass that mediates estrogen deficiency-induced bone loss in mice

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Ditzel, Nicholas; Mahmood, Amer

    2011-01-01

    . In a number of in vitro culture systems, Dlk1 stimulated osteoclastogenesis indirectly through osteoblast-dependent increased production of proinflammatory bone-resorbing cytokines (eg, Il7, Tnfa, and Ccl3). We found that ovariectomy (ovx)-induced bone loss was associated with increased production of Dlk1......Delta-like 1/fetal antigen 1 (DLK1/FA-1) is a transmembrane protein belonging to the Notch/Delta family that acts as a membrane-associated or a soluble protein to regulate regeneration of a number of adult tissues. Here we examined the role of DLK1/FA-1 in bone biology using osteoblast-specific Dlk......1-overexpressing mice (Col1-Dlk1). Col1-Dlk1 mice displayed growth retardation and significantly reduced total body weight and bone mineral density (BMD). Micro-computed tomographis (µCT) scanning revealed a reduced trabecular and cortical bone volume fraction. Tissue-level histomorphometric...

  18. The benefits of a high-intensity aquatic exercise program (HydrOS) for bone metabolism and bone mass of postmenopausal women.

    Science.gov (United States)

    Moreira, Linda Denise Fernandes; Fronza, Fernanda Cerveira A O; Dos Santos, Rodrigo Nolasco; Zach, Patrícia Lins; Kunii, Ilda S; Hayashi, Lilian Fukusima; Teixeira, Luzimar Raimundo; Kruel, Luis Fernando Martins; Castro, Marise Lazaretti

    2014-07-01

    This study aimed to evaluate the 24-week effects of a high-intensity aquatic exercise program on bone remodeling markers and bone mass of postmenopausal women. In this randomized, controlled trial we studied 108 women (58.8 ± 6.4 years), randomized into Aquatic Exercise Group (AEG), n = 64, performing 24 weeks of aquatic exercises, and Control Group (CG), n = 44, sedentary. They had their fasting morning blood sample collected for the measures of intact parathyroid hormone (iPTH), procollagen type 1 amino-terminal propeptide (P1NP) and carboxy-terminal cross-linking telopeptide of type I collagen (CTx). Bone mass was measured by dual-energy X-ray absorptiometry before and after the intervention. Participants of both groups received a daily supplementation of 500 mg of elementary calcium and 1,000 IU of vitamin D (cholecalciferol). Results showed an augment in bone formation marker (P1NP) only in the AEG (15.8 %; p = 0.001), and although both groups experienced significant enhancements in bone resorption marker (CTx), this increase was less considerable in the AEG (15 % in the AEG and 29 % in the CG). IPTH was increased by 19 % in the CG (p = 0.003) at the end. The femoral trochanter BMD presented a 1.2 % reduction in the CG (p = 0.009), whereas in the AEG no change was observed (p = 0.069). The proposed aquatic exercise program was efficient in attenuating bone resorption raise and enhancing bone formation, which prevented the participants in the AEG from reducing the femoral trochanter BMD, as happened in the CG.

  19. New evolutionary sequences for extremely low mass white dwarfs: Homogeneous mass and age determinations, and asteroseismic prospects

    CERN Document Server

    Althaus, Leandro G; Córsico, Alejandro H

    2013-01-01

    We provide a fine and homogeneous grid of evolutionary sequences for He-core white dwarfs with masses 0.15-0.45 Msun, including the mass range for ELM white dwarfs (<0.20Msun). The grid is appropriate for mass and age determination, and to study their pulsational properties. White dwarf sequences have been computed by performing full evolutionary calculations that consider the main energy sources and processes of chemical abundance changes during white dwarf evolution. Initial models for the evolving white dwarfs have been obtained by computing the non-conservative evolution of a binary system consisting of a Msun ZAMS star and a 1.4 Msun neutron star for various initial orbital periods. To derive cooling ages and masses for He-core white dwarf we perform a least square fitting of the M(Teff, g) and Age(Teff, g) relations provided by our sequences by using a scheme that takes into account the time spent by models in different regions of the Teff-g plane. This is useful when multiple solutions for cooling a...

  20. Consumption of different sources of omega-3 polyunsaturated fatty acids by growing female rats affects long bone mass and microarchitecture.

    Science.gov (United States)

    Lukas, Robin; Gigliotti, Joseph C; Smith, Brenda J; Altman, Stephanie; Tou, Janet C

    2011-09-01

    Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) consumption has been reported to improve bone health. However, sources of ω-3 PUFAs differ in the type of fatty acids and structural form. The study objective was to determine the effect of various ω-3 PUFAs sources on bone during growth. Young (age 28d) female Sprague-Dawley rats were randomly assigned (n=10/group) to a high fat 12% (wt) diet consisting of either corn oil (CO) or ω-3 PUFA rich, flaxseed (FO), krill (KO), menhaden (MO), salmon (SO) or tuna (TO) for 8 weeks. Bone mass was assessed by dual-energy X-ray absorptiometry (DXA) and bone microarchitecture by micro-computed tomography (μCT). Bone turnover markers were measured by enzyme immunoassay. Lipid peroxidation was measured by calorimetric assays. Results showed that rats fed TO, rich in docosahexaenoic acid (DHA, 22:6ω-3) had higher (Pacid (ALA, 18:3ω-3), improved bone microarchitecture compared to rats fed CO or SO. Serum osteocalcin was higher (P=0.03) in rats fed FO compared to rats fed SO. Serum osteocalcin was associated with improved trabecular bone microarchitecture. The animal study results suggest consuming a variety of ω-3 PUFA sources to promote bone health during the growth stage.

  1. Reduced Bone and Body Mass in Young Male Rats Exposed to Lead

    Directory of Open Access Journals (Sweden)

    Fellipe Augusto Tocchini de Figueiredo

    2014-01-01

    Full Text Available The aim of this study was to see whether there would be differences in whole blood versus tibia lead concentrations over time in growing rats prenatally. Lead was given in the drinking water at 30 mg/L from the time the dams were pregnant until offspring was 28- or 60-day-old. Concentrations of lead were measured in whole blood and in tibia after 28 (28D and 60 days (60D in control (C and in lead-exposed animals (Pb. Lead measurements were made by GF-AAS. There was no significant difference (P>0.05 in the concentration of whole blood lead between Pb-28D (8.0±1.1 μg/dL and Pb-60D (7.2±0.89 μg/dL, while both significantly varied (P<0.01 from controls (0.2 μg/dL. Bone lead concentrations significantly varied between the Pb-28D (8.02±1.12 μg/g and the Pb-60D (43.3±13.26 μg/g lead-exposed groups (P<0.01, while those exposed groups were also significantly higher (P<0.0001 than the 28D and 60D control groups (Pb < 1 μg/g. The Pb-60D group showed a 25% decrease in tibia mass as compared to the respective control. The five times higher amount of lead found in the bone of older animals (Pb-60D versus Pb-28D, which reinforces the importance of using bone lead as an exposure biomarker.

  2. Prevalence and associated factors of low bone mass in adults with systemic lupus erythematosus.

    Science.gov (United States)

    Cramarossa, G; Urowitz, M B; Su, J; Gladman, D; Touma, Z

    2017-04-01

    Background Systemic lupus erythematosus (SLE) patients are often treated with glucocorticoids, which place them at risk of bone loss. Objectives The objectives of this article are to determine: (1) the prevalence of low bone mineral density (BMD) and factors associated with low BMD and (2) the prevalence of symptomatic fragility fractures in inception patients of the Toronto Lupus Cohort (TLC). Methods Prospectively collected data from the TLC (1996-2015) of inception patients' first BMD were analyzed. For pre-menopausal women/males <50 years, BMD 'below expected range for age' was defined by Z-score ≤ -2.0 SD. For post-menopausal women/males age 50 or older, osteoporosis was defined by T-score ≤ -2.5 SD and low bone mass by T-score between -1.0 and -2.5 SD. Patients' BMDs were defined as abnormal if Z-score ≤ -2.0 or T-score < -1.0 SD, and the remainder as normal. Descriptive analysis and logistic regression were employed. Results Of 1807 patients, 286 are inception patients with BMD results (mean age 37.9 ± 13.7 years); 88.8% are female. The overall prevalence of abnormal BMD is 31.5%. In pre-menopausal women ( n = 173), the prevalence of BMD below expected range is 17.3%. In post-menopausal women ( n = 81), the prevalence of osteoporosis and low BMD are 12.3% and 43.2%, respectively. Age and cumulative dose of glucocorticoids are statistically significantly associated with abnormal BMD in multivariate analysis. Of 769 inception patients from TLC, 11.1% experienced symptomatic fragility fractures (peripheral and vertebral) over the course of their disease. Conclusion The prevalence of low BMD is high in SLE patients, and is associated with older age and higher cumulative glucocorticoid dose.

  3. Establishment of age- and sex-adjusted reference data for hand bone mass and investigation of hand bone loss in patients with rheumatoid arthritis treated in clinical practice

    DEFF Research Database (Denmark)

    Ørnbjerg, Lykke Midtbøll; Østergaard, Mikkel; Jensen, Trine

    2016-01-01

    start), of which 135 patients had three x-rays (~2 years prior to TNFI, at start of TNFI, and ~2 years after TNFI start). Individual HBL/year prior to and during TNFI was calculated and compared to reference values. RESULTS: Estimated HBL/year varied strongly with age and sex. Compared to the reference...... remission (0.0032 vs. 0.0058 g/cm(2)/year; p sex-specific reference values for DXR-BMD in a large cohort without arthritis. HBL was increased in the majority of rheumatoid arthritis patients initiating TNFI in clinical practice, and only......BACKGROUND: Rheumatoid arthritis is characterised by progressive joint destruction and loss of periarticular bone mass. Hand bone loss (HBL) has therefore been proposed as an outcome measure for treatment efficacy. A definition of increased HBL adjusted for age- and sex-related bone loss is lacking...

  4. Relationships between serum omentin-1, body fat mass and bone mineral density in healthy Chinese male adults in Changsha area.

    Science.gov (United States)

    Li, X P; Zeng, S; Wang, M; Wu, X P; Liao, E Y

    2014-10-01

    The present study is firstly designed to identify the relationship between serum omentin-1 concentration, body fat mass and bone mineral density in healthy Chinese male adults in Changsha city. A total of 219 (20-80 years old) healthy subjects were enrolled in this cross-sectional study. Serum omentin-1, adiponectin, leptin, resistin and bone turn over biochemical markers were measured with enzyme-linked immunosorbent assay. Bone mineral density (BMD) and fat body composition were determined using dual-energy-X-ray absorptiometry. Serum omentin-1 levels in the overweight subjects were significantly lower than those of the subjects with normal weight (p fat body mass (FBM, r = -0.430), fat % (r = -0.408), trunk fat (-0.431). However, after controlling for age, BMI and FBM, no significant correlation was noticed between omentin-1 and BMD at different skeletal sites. Pearson's correlation coefficients and partial correlation coefficients after adjustment showed no significant correlations between omentin-1 and bone turn over biochemical markers, including bone-specific alkaline phosphatase and bone cross-linked N-terminal telopeptides of type I collagen. Multiple line stepwise regression analysis revealed that FBM, WHR, adiponectin were important variables affecting omentin-1. Moreover, lean tissue mass was the most important factor affecting BMD and explained 10.5-14.7 % of the variance. Omentin-1, leptin and resistin were not the predictors of BMD. Serum omentin-1 was negatively correlated with FBM and BMI in healthy Chinese male adults, It was not significantly correlated with bone turnover biochemical markers. Omentin-1 may exert ambiguous effects on BMD, which maybe caused by the complex interactions among adipokines, hormonal activity, and body composition and bone metabolism.

  5. From superdeformation to extreme deformation and clusterization in the N~Z nuclei of the A~40 mass region

    CERN Document Server

    Ray, D

    2016-01-01

    A systematic search for extremely deformed structures in the N~Z nuclei of the A~40 mass region has been performed for the first time in the framework of covariant density functional theory. At spin zero such structures are located at high excitation energies which prevents their experimental observation. The rotation acts as a tool to bring these exotic shapes to the yrast line or its vicinity so that their observation could become possible with future generation of $\\gamma-$tracking (or similar) detectors such as GRETA and AGATA. The major physical observables of such structures (such as transition quadrupole moments as well as kinematic and dynamic moments of inertia), the underlying single-particle structure and the spins at which they become yrast or near yrast are defined. The search for the fingerprints of clusterization and molecular structures is performed and the configurations with such features are discussed. The best candidates for observation of extremely deformed structures are identified. For ...

  6. Effect of hormone replacement therapy on the bone mass and urinary excretion of pyridinium cross-links

    Directory of Open Access Journals (Sweden)

    Dolores Perovano Pardini

    2000-01-01

    Full Text Available CONTEXT: The menopause accelerates bone loss and is associated with an increased bone turnover. Bone formation may be evaluated by several biochemical markers. However, the establishment of an accurate marker for bone resorption has been more difficult to achieve. OBJECTIVE: To study the effect of hormone replacement therapy (HRT on bone mass and on the markers of bone resorption: urinary excretion of pyridinoline and deoxypyridinoline. DESIGN: Cohort correlational study. SETTING: Academic referral center. SAMPLE: 53 post-menopausal women, aged 48-58 years. MAIN MEASUREMENTS: Urinary pyr and d-pyr were measured in fasting urine samples by spectrofluorometry after high performance liquid chromatography and corrected for creatinine excretion measured before treatment and after 1, 2, 4 and 12 months. Bone mineral density (BMD was measured by dual energy X-ray absorptiometry (DEXA before treatment and after 12 months of HRT. RESULTS: The BMD after HRT was about 4.7% (P < 0.0004; 2% (P < 0.002; and 3% (P < 0.01 higher than the basal values in lumbar spine, neck and trochanter respectively. There were no significant correlations between pyridinium cross-links and age, weight, menopause duration and BMD. The decrease in pyr and d-pyr was progressive after HRT, reaching 28.9% (P < 0.0002, and 42% (P < 0.0002 respectively after 1 year. CONCLUSIONS: Urinary pyridinoline and deoxypyridinoline excretion decreases early in hormone replacement therapy, reflecting a decrease in the bone resorption rate, and no correlation was observed with the bone mass evaluated by densitometry.

  7. ZP2307, a novel, cyclic PTH(1-17) analog that augments bone mass in ovariectomized rats.

    Science.gov (United States)

    Neerup, Trine S R; Stahlhut, Martin; Petersen, Jørgen S; Daugaard, Jens R; Jensen, Jens-Erik B; Peng, Zhiqi; Morko, Jukka; Thorkildsen, Christian

    2011-06-01

    Daily injections of human parathyroid hormone (1-34), hPTH(1-34), provide a highly effective treatment option for severe osteoporosis. However, PTH analogs shorter than 28 amino acids do not retain any bone augmenting potential. Here, we present ZP2307 ([Ac₅c¹, Aib³, Leu⁸, Gln¹⁰, Har¹¹, Ala¹², Trp¹⁴, Asp¹⁷]PTH(1-17)-NH₂), a novel, chemically modified and cyclized hPTH(1-17) analog, that augments bone mass in ovariectomized, osteopenic rats. Subcutaneous administration of this structurally constrained, K¹³-D¹⁷ side-chain-to-side-chain cyclized peptide reversed bone loss and increased bone mineral density (BMD) up to or above baseline levels in rat long bones and vertebrae. Highly significant effects of ZP2307 were achieved at doses of 40-320 nmol/kg. Micro-CT and histomorphometric analyses showed that ZP2307 improved quantitative and qualitative parameters of bone structure. Biomechanical testing of rat femora confirmed that ZP2307 dramatically increased bone strength. Over a broad maximally effective dose range (40-160 nmol/kg) ZP2307 did not increase serum concentrations of ionized free calcium above normal levels. Only at the highest dose (320 nmol/kg) ZP2307 induced hypercalcemic calcium levels in the ovariectomized rats. To our knowledge ZP2307 is the smallest PTH peptide analog known to exert augmentation of bone. Our findings suggest that ZP2307 has the potential to effectively augment bone mass over a broad dose range without a concomitant increase in the serum concentration of ionized free calcium above the normal range.

  8. Low Bone Mass is Associated with Stroke in Chinese Postmenopausal Women: The Chongqing Osteoporosis Study.

    Science.gov (United States)

    Zhou, Rui; Liu, Dong; Li, Rui; Zhou, Shiming; Cui, Min; Chen, Lin; Zhou, Huadong

    2015-04-01

    The objective of the present study was to investigate the association of low bone mass with the risk of stroke and death in community residents of China. This study was based on the follow-up data acquired from 5,136 postmenopausal women aged 50 years or older between July 2006 and June 2011. Baseline and the follow-up bone mineral density (BMD) in these patients were measured by dual energy X-ray absorptiometry scanning. The association of BMD and risk of stroke and death was further evaluated by Cox proportional hazard analysis. During the follow-up, 148 subjects (2.9%) sustained prospective stroke, and 261 subjects (5.1%) died. After adjustments for age and BMI, our results indicated that neck BMD and osteoporosis were independent predictors of stroke (HR for neck BMD = 1.35, 95% CI = 1.21-1.62; HR for osteoporosis = 2.24, 95% CI = 1.47-3.58) and were also associated with increased risk of death (HR for neck BMD = 1.39, 95% CI = 1.24-1.71; HR for osteoporosis = 1.97, 95% CI = 1.21-2.97). Our results also suggest that low neck BMD and osteoporosis are associated with significantly elevated risk of stroke and death in Chinese postmenopausal women.

  9. Neonatal High Bone Mass With First Mutation Of The NF-κB Complex

    DEFF Research Database (Denmark)

    Frederiksen, Anja Lisbeth; Larsen, Martin Jakob; Brusgaard, Klaus

    2016-01-01

    Heritable disorders that feature high bone mass (HBM) are rare. The etiology is typically a mutation(s) within a gene that regulates the differentiation and function of osteoblasts (OBs) or osteoclasts (OCs). Nevertheless, the molecular basis is unknown for approximately one-fifth of such entities...... within the genes that encode the NF-κB complex, including the Rela/p65 subunit, have not been reported. We describe a neonate who died suddenly and unexpectedly and was found at postmortem to have HBM documented radiographically and by skeletal histopathology. Serum was not available for study...... fibroblasts elicited impaired NF-κB responses compared with healthy control fibroblasts. Five unrelated patients with unexplained HBM did not show a RELA defect. Ours is apparently the first report of a mutation within the NF-κB complex in humans. The missense change is associated with neonatal osteosclerosis...

  10. Pulsed electromagnetic fields partially preserve bone mass, microarchitecture, and strength by promoting bone formation in hindlimb-suspended rats.

    Science.gov (United States)

    Jing, Da; Cai, Jing; Wu, Yan; Shen, Guanghao; Li, Feijiang; Xu, Qiaoling; Xie, Kangning; Tang, Chi; Liu, Juan; Guo, Wei; Wu, Xiaoming; Jiang, Maogang; Luo, Erping

    2014-10-01

    A large body of evidence indicates that pulsed electromagnetic fields (PEMF), as a safe and noninvasive method, could promote in vivo and in vitro osteogenesis. Thus far, the effects and underlying mechanisms of PEMF on disuse osteopenia and/or osteoporosis remain poorly understood. Herein, the efficiency of PEMF on osteoporotic bone microarchitecture, bone strength, and bone metabolism, together with its associated signaling pathway mechanism, was systematically investigated in hindlimb-unloaded (HU) rats. Thirty young mature (3-month-old), male Sprague-Dawley rats were equally assigned to control, HU, and HU + PEMF groups. The HU + PEMF group was subjected to daily 2-hour PEMF exposure at 15 Hz, 2.4 mT. After 4 weeks, micro-computed tomography (µCT) results showed that PEMF ameliorated the deterioration of trabecular and cortical bone microarchitecture. Three-point bending test showed that PEMF mitigated HU-induced reduction in femoral mechanical properties, including maximum load, stiffness, and elastic modulus. Moreover, PEMF increased serum bone formation markers, including osteocalcin (OC) and N-terminal propeptide of type 1 procollagen (P1NP); nevertheless, PEMF exerted minor inhibitory effects on bone resorption markers, including C-terminal crosslinked telopeptides of type I collagen (CTX-I) and tartrate-resistant acid phosphatase 5b (TRAcP5b). Bone histomorphometric analysis demonstrated that PEMF increased mineral apposition rate, bone formation rate, and osteoblast numbers in cancellous bone, but PEMF caused no obvious changes on osteoclast numbers. Real-time PCR showed that PEMF promoted tibial gene expressions of Wnt1, LRP5, β-catenin, OPG, and OC, but did not alter RANKL, RANK, or Sost mRNA levels. Moreover, the inhibitory effects of PEMF on disuse-induced osteopenia were further confirmed in 8-month-old mature adult HU rats. Together, these results demonstrate that PEMF alleviated disuse-induced bone loss by promoting skeletal anabolic activities

  11. Osteoblast-targeted overexpression of PPARγ inhibited bone mass gain in male mice and accelerated ovariectomy-induced bone loss in female mice.

    Science.gov (United States)

    Cho, Sun Wook; Yang, Jae-Yeon; Her, Sun Ju; Choi, Hyung Jin; Jung, Ju Yeon; Sun, Hyun Jin; An, Jee Hyun; Cho, Hwa Young; Kim, Sang Wan; Park, Kyong Soo; Kim, Seong Yeon; Baek, Wook-Young; Kim, Jung-Eun; Yim, Mijung; Shin, Chan Soo

    2011-08-01

    PPARγ has critical role in the differentiation of mesenchymal stem cells into adipocytes while suppressing osteoblastic differentiation. We generated transgenic mice that overexpress PPARγ specifically in osteoblasts under the control of a 2.3-kb procollagen type 1 promoter (Col.1-PPARγ). Bone mineral density (BMD) of 6- to 14-week-old Col.1 - PPARγ male mice was 8% to 10% lower than that of their wild-type littermates, whereas no difference was noticed in Col.1-PPARγ female mice. Col.1-PPARγ male mice exhibited decreased bone volume (45%), trabecular thickness (23%), and trabecular number (27%), with a reciprocal increase in trabecular spacing (51%). Dynamic histomorphometric analysis also revealed that bone-formation rate (42%) and mineral apposition rate (32%) were suppressed significantly in Col.1-PPARγ male mice compared with their wild-type littermates. Interestingly, osteoclast number and surface also were decreased by 40% and 58%, respectively, in Col.1-PPARγ male mice. In vitro whole-marrow culture for osteoclastogenesis also showed a significant decrease in osteoclast formation (approximately 35%) with the cells from Col.1-PPARγ male mice, and OPG/RANKL ratio was reduced in stromal cells from Col.1-PPARγ male mice. Although there was no significant difference in BMD in Col.1-PPARγ female mice up to 30 weeks, bone loss was accelerated after ovariectomy compared with wild-type female mice (-3.9% versus -6.8% at 12 weeks after ovariectomy, p bone mass in male mice and accelerates estrogen-deficiency-related bone loss in female mice. Copyright © 2011 American Society for Bone and Mineral Research.

  12. Association of vitamin D receptor and estrogen receptor-α gene polymorphism with peak bone mass and bone size in Chinese women

    Institute of Scientific and Technical Information of China (English)

    Yue-juan QIN; Zhen-lin ZHANG; Qi-ren HUANG; Jin-wei HE; Yun-qiu HU; Qi ZHOU; Jing-hui LU; Miao LI; Yu-juan LIU

    2004-01-01

    AIM: To investigate if vitamin D receptor (VDR) gene Apa I polymorphism and estrogen receptor-α (ER-α) gene Pvu II, Xba I polymorphisms are related to bone mineral density (BMD), bone mineral content (BMC) and bone size in premenopausal Chinese women. METHODS: The VDR Apa I genotype and ER-α Pvu II, Xba I genotype were determined by PCR-restriction fragment length polymorphism (RFLP) in 493 unrelated healthy women aged 20-40 years of Hah nationality in Shanghai city. BMD (g/cm2), BMC (g), and bone areal size (BAS, cm2) at lumbar spine 1-4 (L1-4) and proximal femur (femoral neck, trochanter and Ward's triangle) were measured by duel-energy X-ray absorptionmetry. RESULTS: All allele frequencies did not deviate from Hardy-Weinberg equilibrium. After phenotypes were adjusted for age, height, and weight, a significant association was found between VDR Apa I genotype and BMC variation at L1-4 and Ward's triangle (P<0.05), but not in BMD or BAS at lumbar spine and proximal femur.ER-α Pvu II, Xba I genotype was not related to BMC, BMD, and BAS at all sites. CONCLUSION: The study suggested that Apa I polymorphism in VDR gene may influence on attainment and maintenance of peak bone mass in premenopausal Chinese women.

  13. Differential diagnosis between chronic otitis media with and without cholesteatoma by temporal bone CT: focus on bone change and mass effect

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Cheol Kyu; Park, Dong Woo; Seong, Jin Yong; Lee, Kak Soo; Park Choong Ki; Lee, Seung Ro; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    2000-01-01

    flaccida (35%, 9%) were more common in COM with cholesteatoma (p-value less than 0.05). Soft tissue in Prussak's space (58%, 72%), retraction of the tympanic membrane (19%, 9%), and tympanosclerosis (8%, 10%) were not however, important findings (p-value greater than 0.05). Bone erosion or destruction was seen in COM without cholesteatoma, but expansile bone erosion or destruction with mass effect suggested COM with cholesteatoma. These findings of temporal bone CT in COM demonstrate the existence and extent of combined cholesteatoma, and are therefore valuable. (author)

  14. The Survey of HI in Extremely Low-mass Dwarfs: A Multi-Wavelength Perspective on Low-Mass Galaxy Evolution

    Science.gov (United States)

    Cannon, John M.; McNichols, Andrew; Teich, Yaron; Adams, Elizabeth A.; Giovanelli, Riccardo; Haynes, Martha P.; McQuinn, Kristen B.; Salzer, John Joseph; Skillman, Evan D.; Dolphin, Andrew E.; Elson, Edward C.; Haurberg, Nathalie C.; Huang, Shan; Janowiecki, Steven; Jozsa, Gyula; Leisman, Luke; Ott, Juergen; Papastergis, Emmanouil; Rhode, Katherine L.; Saintonge, Amelie; Van Sistine, Angela; Warren, Steven R.

    2017-01-01

    The “Survey of HI in Extremely Low-mass Dwarfs” (SHIELD) is a multiwavelength study of local volume low-mass galaxies drawn from the Arecibo Legacy Fast ALFA (ALFALFA) catalog. HST/Spitzer joint program GO-12658 revealed the stellar populations of the first 12 SHIELD galaxies (Cannon et al. 2011), allowing accurate distance measurements (McQuinn et al. 2014) and detailed studies of the patterns of recent star formation in each galaxy (McQuinn et al. 2015). These HST and Spitzer images are a critical interpretive benchmark for ground-based optical imaging and spectroscopy (Haurberg et al. 2015), as well as for sensitive VLA HI spectral line imaging of the SHIELD galaxies (McNichols et al. 2016; Teich et al. 2016). These results have furthered our understanding of the evolution of galaxies in a mass regime that was previously only sparsely populated. With the low-redshift ALFALFA catalog now complete, the scope of the SHIELD program has been expanded to include all 82 galaxies that meet distance, line width, and HI flux criteria for being gas-rich, low-mass galaxies. In HST program 13750, images of 18 more SHIELD galaxies have again set the physical scales for supporting HI spectral line imaging with both the VLA and the WSRT (Gordon et al. 2016). Taken as a whole, the ongoing SHIELD program is one of the most comprehensive multiwavelength studies of the physical properties of low-mass galaxies outside of the Local Group.

  15. Prevalence of Low Bone Mass and Osteoporosis in Long-Term Users of the Injectable Contraceptive Depot Medroxyprogesterone Acetate.

    Science.gov (United States)

    Modesto, Waleska; Bahamondes, M Valeria; Bahamondes, Luis

    2015-08-01

    Bone mineral density (BMD) loss among depot medroxyprogesterone acetate (DMPA) users is a controversial issue. Aspects under debate include whether the number of years of use has any effect on continuous BMD loss, whether this loss will stabilise over the years of use or if it will progress to low bone mass, osteoporosis and an increased fracture risk. The aim of this study was to compare the difference in osteoporosis and low bone mass between DMPA and copper intrauterine device (Cu-IUD) users. This was a cross-sectional study that evaluated BMD at the lumbar spine and femoral neck in 47 long-term DMPA users and 41 Cu-IUD users as control group. BMD was measured by dual-energy X-ray absorptiometry. The participants were 27 to 57 years of age, had used either DMPA or a Cu-IUD uninterruptedly for at least ten years, had initiated use of the method prior to 40 years of age and had follicle stimulating hormone values <40 mIU/mL. Findings showed that 68.1% and 36.6% of the DMPA and Cu-IUD users, respectively, had low bone mass and 29.8% and 2.4% of DMPA and Cu-IUD users, respectively, had osteoporosis. BMD decreased as the number of years of DMPA use increased. Long-term DMPA use was associated with low bone mass and osteoporosis in women who had used the method for 10 years or more. DMPA users with longer time of use showed a greater bone mass loss.

  16. Risk of non-spine fractures among older men and women with sarcopenia, low bone mass, or both

    Science.gov (United States)

    Chalhoub, Didier; Cawthon, Peggy M.; Ensrud, Kristine E.; Stefanick, Marcia L.; Kado, Deborah M.; Boudreau, Robert; Greenspan, Susan; Newman, Anne; Zmuda, Joseph; Orwoll, Eric S.; Cauley, Jane A.

    2015-01-01

    Objectives To test the hypothesis that men and women with both low bone mineral density and sarcopenia have a higher risk of fracture than those with only one or neither conditions. Design The Osteoporotic Fractures in Men study and the Study of Osteoporotic Fractures in women are prospective observational studies with a mean follow up of 9 years (2000–2012) and 8years (1997–2009) respectively. Setting US clinical centers Participants 5,544 men (mean age=73.7 years) and 1,114 women (mean age=77.6 years); all ≥age 65; able to walk without assistance, and without bilateral hip replacement. Measurements Sarcopenia was defined as low appendicular lean mass plus either slowness or weakness; and low bone mineral density, by the World Health Organization definition of T-scoresarcopenia (N=3367 men, 308 women); sarcopenic only (N=79 men; 48 women); low bone mineral density only (N=1986 men; 626 women), and low bone mineral density and sarcopenic (N=112 men; 132 women). Results Compared to men with normal bone mineral density and no sarcopenia, the Hazard ratio [HR] for fracture was 3.79 (95% confidence interval [CI], 2.65–5.41) among men with low bone mineral density and sarcopenia, 1.67 (95% CI, 1.45–1.93) among men with low bone mineral density only, and 1.14 (95% CI, 0.62–2.09) among men with sarcopenia only. Women with low bone mineral density and sarcopenia (HR, 2.27; 95% CI, 1.37–3.76), and women with low bone mineral density alone (HR, 2.62; 95% CI, 1.74–3.95), but not women with only sarcopenia had increased risk of fracture compared to normal women. Conclusion Men with both low bone mineral density and sarcopenia are at especially high risk of fracture. PMID:26310882

  17. Intercalary Reconstruction after Wide Resection of Malignant Bone Tumors of the Lower Extremity Using a Composite Graft with a Devitalized Autograft and a Vascularized Fibula

    Directory of Open Access Journals (Sweden)

    Koichi Ogura

    2015-01-01

    Full Text Available Introduction. Although several intercalary reconstructions after resection of a lower extremity malignant bone tumor are reported, there are no optimal methods which can provide a long-term reconstruction with fewest complications. We present the outcome of reconstruction using a devitalized autograft and a vascularized fibula graft composite. Materials and Methods. We conducted a retrospective review of 11 patients (7 males, 4 females; median age 27 years undergoing reconstruction using a devitalized autograft (pasteurization (n=6, deep freezing (n=5 and a vascularized fibula graft composite for lower extremity malignant bone tumors (femur (n=10, tibia (n=1. Results. The mean period required for callus formation and bone union was 4.4 months and 9.9 months, respectively. Four postoperative complications occurred in 3 patients: 2 infections (1 pasteurized autograft, 1 frozen autograft and 1 fracture and 1 implant failure (both in pasteurized autografts. Graft removal was required in 2 patients with infections. The mean MSTS score was 81% at last follow-up. Conclusions. Although some complications were noted in early cases involving a pasteurized autograft, our novel method involving a combination of a frozen autograft with a vascularized fibula graft and rigid fixation with a locking plate may offer better outcomes than previously reported allografts or devitalized autografts.

  18. Calabi-Yau Compactification of Type-Iib String and a Mass Formula of the Extreme Black Holes

    Science.gov (United States)

    Suzuki, Hisao

    Recently proposed mechanism of the black hole condensation at conifold singularity in type-II string is an interesting idea from which we can interpret the phase of the universal moduli space of the string vacua. It might also be expected that the true physics is on the conifold singularity after supersymmetry breaking. We derive a mass formula for the extreme black holes caused by the self-dual five-form field strength, which is stable and supersymmetric. It is shown that the formula can be written by the moduli parameters of Calabi-Yau manifold and can be calculated explicitly.

  19. Estrogens maintain bone mass by regulating expression of genes controlling function and life span in mature osteoclasts.

    Science.gov (United States)

    Imai, Yuuki; Youn, Ming-Young; Kondoh, Shino; Nakamura, Takashi; Kouzmenko, Alexander; Matsumoto, Takahiro; Takada, Ichiro; Takaoka, Kunio; Kato, Shigeaki

    2009-09-01

    Estrogens play a key role in regulation of bone mass and strength by controlling activity of bone-forming osteoblasts and bone-resorbing osteoclasts. Cellular effects of estrogens are mediated predominantly by the action of estrogen receptor alpha (ERalpha). In earlier studies, ablation of the ERalpha gene in mice did not result in osteoporotic phenotypes due to systemic endocrine disturbance and compensatory effects of elevated levels of testosterone. Despite the relatively well-established effects in osteoblasts, little is known about the direct action of estrogen in osteoclasts. Development in the last decade of more sophisticated genetic manipulation approaches opened new possibilities to explore cell-specific roles of nuclear receptors in bone tissue. Recently, we have generated osteoclast-specific ERalpha gene knockout mice and shown that in vivo estrogens directly regulate the life span of mature osteoclasts by inducing the expression of pro-apoptotic Fas ligand (FasL). Inhibitory effects of estrogens on osteoclast function were further studied in vitro. We observed sufficiently detectable ERalpha expression in osteoclasts differentiating from primary bone marrow cells or RAW264 cells, although levels of ERalpha were decreasing during progression of the differentiation into mature osteoclasts. Treatment with estrogens led to reduction in expression of osteoclast-specific genes controlling bone resorption activity. However, estrogens did not affect the size of multinucleated osteoclasts or number of nuclei in a mature osteoclast. In conclusion, in osteoclasts, estrogens function to inhibit bone resorption activity and vitality rather than differentiation.

  20. Amino acid δ13C analysis of hair proteins and bone collagen using liquid chromatography/isotope ratio mass spectrometry

    DEFF Research Database (Denmark)

    Raghavan, Maanasa; McCullagh, James S. O.; Lynnerup, Niels

    2010-01-01

    We report a novel method for the chromatographic separation and measurement of stable carbon isotope ratios (delta(13)C) of individual amino acids in hair proteins and bone collagen using the LC-IsoLink system, which interfaces liquid chromatography (LC) with isotope ratio mass spectrometry (IRMS......). This paper provides baseline separation of 15 and 13 of the 18 amino acids in bone collagen and hair proteins, respectively. We also describe an approach to analysing small hair samples for compound-specific analysis of segmental hair sections. The LC/IRMS method is applied in a historical context...... by the delta(13)C analysis of hair proteins and bone collagen recovered from six individuals from Uummannaq in Greenland. The analysis of hair and bone amino acids from the same individual, compared for the first time in this study, is of importance in palaeodietary reconstruction. If hair proteins can be used...

  1. Pb distribution in bones from the Franklin expedition: synchrotron X-ray fluorescence and laser ablation/mass spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Ronald Richard; Naftel, Steven; Macfie, Sheila; Jones, Keith; Nelson, Andrew [The University of Western Ontario, London, ON (Canada)

    2013-04-15

    Synchrotron micro-X-ray Fluorescence has been used to map the metal distribution in selected bone fragments representative of remains associated with the Franklin expedition. In addition, laser ablation mass spectroscopy using a 25 {mu}m diameter circular spot was employed to compare the Pb isotope distributions in small regions within the bone fragments. The X-ray Fluorescence mapping shows Pb to be widely distributed in the bone while the Pb isotope ratios obtained by laser ablation within small areas representative of bone with different Pb exchange rates do not show statistically significant differences. These results are inconsistent with the hypothesis that faulty solder seals in tinned meat were the principle source of Pb in the remains of the expedition personnel. (orig.)

  2. Prospects for measuring supermassive black hole masses with future extremely large telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Do, Tuan; Wright, Shelley A. [Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto M5S 3H4, ON (Canada); Barth, Aaron J.; Barton, Elizabeth J. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697-4575 (United States); Simard, Luc [Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC, V9E 2E7 (Canada); Larkin, James E. [Physics and Astronomy Department, University of California, Los Angeles, CA 90095-1547 (United States); Moore, Anna M. [Caltech Optical Observatories, California Institute of Technology, Pasadena, CA (United States); Wang, Lianqi; Ellerbroek, Brent [TMT Observatory Corporation Instrumentation Department, Pasadena, CA (United States)

    2014-04-01

    The next generation of giant-segmented mirror telescopes (>20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from Z band (0.9 μm) to K band (2.2 μm). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of ∼10{sup 4} M {sub ☉} to the most massive black holes known today of >10{sup 10} M {sub ☉}. We find that IRIS will be able to observe Milky Way mass black holes out the distance of the Virgo Cluster, and will allow us to observe many more of the brightest cluster galaxies where the most massive black holes are thought to reside. We also evaluate how well the kinematic moments of the velocity distributions can be constrained at the different spectral resolutions and plate scales designed for IRIS. We find that a spectral resolution of ∼8000 will be necessary to measure the masses of intermediate mass black holes. By simulating the observations of galaxies found in Sloan Digital Sky Survey DR7, we find that over 10{sup 5} massive black holes will be observable at distances between 0.005 < z < 0.18 with the estimated sensitivity and angular resolution provided by access to Z-band (0.9 μm) spectroscopy from IRIS and the TMT adaptive optics system. These observations will provide the most accurate dynamical measurements of black hole masses to

  3. Prednisone treatment of elderly-onset rheumatoid arthritis: Disease activity and bone mass in comparison with chloroquine treatment

    NARCIS (Netherlands)

    D. van Schaardenburg (Dirkjan); R. Valkema (Roelf); B.A.C. Dijkmans (Ben); S.E. Papapoulos (Socrates); A.H. Zwinderman (Ailko); K.H. Han (Hubert); E.K.J. Pauwels (Ernest K.J); F.C. Breedveld (Ferdinand)

    1995-01-01

    textabstractObjective. Prednisone is frequently used in the treatment of elderly-onset rheumatoid arthritis (RA), but the balance between efficacy and toxicity, including the effect on bone mass, has not been investigated in long-term studies. This prospective, randomized study was undertaken to com

  4. The role of body mass index, insulin, and adiponectin in the relation between fat distribution and bone mineral density

    NARCIS (Netherlands)

    M.C. Zillikens (Carola); A.G. Uitterlinden (André); J.P.T.M. van Leeuwen (Hans); A.L. Berends (Anne); P. Henneman (Peter); J.A.P. Willems van Dijk (Ko); B.A. Oostra (Ben); C.M. van Duijn (Cock); H.A.P. Pols (Huib); F. Rivadeneira Ramirez (Fernando)

    2010-01-01

    textabstractDespite the positive association between body mass index (BMI) and bone mineral density (BMD) and content (BMC), the role of fat distribution in BMD/BMC remains unclear. We examined relationships between BMD/BMC and various measurements of fat distribution and studied the role of BMI, in

  5. Prednisone treatment of elderly-onset rheumatoid arthritis: Disease activity and bone mass in comparison with chloroquine treatment

    NARCIS (Netherlands)

    D. van Schaardenburg (Dirkjan); R. Valkema (Roelf); B.A.C. Dijkmans (Ben); S.E. Papapoulos (Socrates); A.H. Zwinderman (Ailko); K.H. Han (Hubert); E.K.J. Pauwels (Ernest K.J); F.C. Breedveld (Ferdinand)

    1995-01-01

    textabstractObjective. Prednisone is frequently used in the treatment of elderly-onset rheumatoid arthritis (RA), but the balance between efficacy and toxicity, including the effect on bone mass, has not been investigated in long-term studies. This prospective, randomized study was undertaken to

  6. Effects of estrogen with micronized progesterone on cortical and trabecular bone mass and microstructure in recently postmenopausal women.

    Science.gov (United States)

    Farr, Joshua N; Khosla, Sundeep; Miyabara, Yuko; Miller, Virginia M; Kearns, Ann E

    2013-02-01

    In women, cortical bone mass decreases significantly at menopause. By contrast, loss of trabecular bone begins in the third decade and accelerates after menopause. The aim of the study was to investigate the effects of estrogen on cortical and trabecular bone. The Kronos Early Estrogen Prevention Study is a double-blind, randomized, placebo-controlled trial of menopausal hormone treatment (MHT) in women, enrolled within 6-36 months of their final menstrual period. The study was conducted at the Mayo Clinic, Rochester, Minnesota. Subjects were treated with placebo (n = 31), or .45 mg/d conjugated equine estrogens (n = 20), or transdermal 50 μg/d 17β-estradiol (n = 25) with pulsed micronized progesterone. Cortical and trabecular microarchitecture at the distal radius was assessed by high-resolution peripheral quantitative computed tomography. At the distal radius, cortical volumetric bone mineral density (vBMD) decreased, and cortical porosity increased in the placebo group; MHT prevented these changes. By contrast, MHT did not prevent decreases in trabecular microarchitecture at the radius. However, MHT prevented decreases in trabecular vBMD at the thoracic spine (assessed in a subset of subjects; n = 51). These results indicate that MHT prevents deterioration in radial cortical vBMD and porosity in recently menopausal women. The maintenance of cortical bone in response to estrogen likely has important clinical implications because cortical bone morphology plays an important role in bone strength. However, effects of MHT on trabecular bone at the radius differ from those at the thoracic spine. Underlying mechanisms for these site-specific effects of MHT on cortical vs trabecular bone require further investigation.

  7. Bone mass loss is associated with systolic blood pressure in postmenopausal women with type 2 diabetes in Tibet: a retrospective cross-sectional study.

    Science.gov (United States)

    Zhou, L; Song, J; Yang, S; Meng, S; Lv, X; Yue, J; Mina, A; Puchi, B; Geng, Y; Yang, L

    2017-02-02

    We conducted an observational cross-section study to investigate the status of bone mineral mass of Tibetan postmenopausal women with type 2 diabetes and the possible predictors for osteoporosis. We found that prevalence of osteoporosis was 27.0% and blood pressure was an independent risk factor for bone mass loss.

  8. The importance of transient resonances in extreme-mass-ratio inspirals

    CERN Document Server

    Berry, Christopher P L; Cañizares, Priscilla; Gair, Jonathan R

    2016-01-01

    The inspiral of stellar-mass compact objects, like neutron stars or stellar-mass black holes, into supermassive black holes provides a wealth of information about the strong gravitational-field regime via the emission of gravitational waves. In order to detect and analyse these signals, accurate waveform templates which include the effects of the compact object's gravitational self-force are required. For computational efficiency, adiabatic templates are often used. These accurately reproduce orbit-averaged trajectories arising from the first-order self-force, but neglect other effects, such as transient resonances, where the radial and poloidal fundamental frequencies become commensurate. During such resonances the flux of gravitational waves can be diminished or enhanced, leading to a shift in the compact object's trajectory and the phase of the waveform. We present an evolution scheme for studying the effects of transient resonances and apply this to an astrophysically motivated population. We find that a ...

  9. Massive Stars and their Siblings: the Extreme End of the Companion Mass Function

    Science.gov (United States)

    de Mink, Selma

    2014-10-01

    The gold-rush for detecting exoplanets has lead to an exponential improvement of optimization algorithms for high-contrast imaging optimized for HST. We propose to exploit these to probe the virtually unexplored population of low mass stars in the very close vicinity of young massive stars in order to I. progress our understanding of how low-mass stars form and survive under the influence of the ionizing radiation of their massive host and II. provide urgently needed constraints on competing theories of massive star formation by measuring their multiplicity. The high spatial and temporal stability of HST's point spread function is essential for the detection of very faint companions down to sub-arcsecond separations even in crowded regions at contrast up to delta-mag ~ 10, i.e. flux ratios up to 10,000. Furthermore the characterization of the low mass companions calls for wavelength bands largely affected by absorption by H2O in the earth's atmosphere. To achieve this goal we propose to use WFC3/IR to observe two adjacent fields in the center of the very young, nearby star cluster Trumpler 14, which harbors a rich population of massive stars.

  10. New CCD photometry for the extreme lower mass-ratio binary AW Ursae Majoris

    Science.gov (United States)

    Yang, Yuangui

    2008-04-01

    This paper presents charge-couple device (CCD) photometric observations for the eclipsing binary AW UMa. The V-band light curve in 2007 was analyzed using the 2003 version of the Wilson Devinney code. It is confirmed that AW UMa is a total eclipsing binary with a higher degree of contact f=80.2% and a lower mass ratio of q=0.076. From the ( O- C) curve, the orbital period shows a continuous period decrease at a rate of dP/ dt=-2.05×10-7 d yr-1. The long-term period decrease suggested that AW UMa is undergoing the mass transfer from the primary component to the secondary one, accompanied by angular momentum loss due to mass outflow L 2. Weak evidence indicates that there exists a cyclic variation with a period of 17.6 yr and a small amplitude of A=0. d 0019, which may be attributed to the light-time effect via the third body. If the existence of an additional body is true, it may remove a great amount of angular momentum from the central system. For this kind of contact binary, as the orbital period decreases, the shrinking of the inner and outer critical Roche lobes will cause the contact degree f to increase. Finally, this kind of binary will merge into a single rapid-rotation star.

  11. Prospects for measuring supermassive black hole masses with future extremely large telescopes

    CERN Document Server

    Do, Tuan; Barth, Aaron J; Barton, Elizabeth J; Simard, Luc; Larkin, James E; Moore, Anna M; Wang, Lianqi; Ellerbroek, Brent

    2014-01-01

    The next generation of giant-segmented mirror telescopes ($>$ 20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from $Z$ band (0.9 $\\mu$m) to $K$ band (2.2 $\\mu$m). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument, to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of $\\sim10^4$ \\msun to the most massive black holes known today of $>10^{10}...

  12. Dinosaur bone beds and mass mortality: Implications for the K-T extinction

    Science.gov (United States)

    Carpenter, Kenneth

    1988-01-01

    Mass accumulations of fossilized large terrestrial vertebrate skeletons (bone beds: BB) provide a test for K-T catastrophic extinction hypotheses. The two major factors contributing to BB formation are mode of death and sedimentation rate. Catastrophic mass mortality (CMM) is the sudden death of numerous individuals where species, age, health, gender, or social ranking offer no survivorship advantage. Noncatastrophic mass mortality (NCMM) occurs over time and is strongly influenced by species, age, or gender. In addition to cause of death, sedimentation rate is also important in BB formation. Models of BBs can be made. The CMM drops all individuals in their tracks, therefore, the BB should reflect the living population with respect to species, age, or gender. The NCMM results in monospecific BBs skewed in the direction of the less fit, usually the very young or very old, or towards a specific gender. The NCMM and AM BBs may become more similar the more spread out over time NCMM deaths occur because carcasses are widely scattered requiring hydraulic accumulation, and the greater time allows for more disarticulation and weathering. The CMM and NCMM BB appear to be dominated by social animals. Applying this and the characteristics of mortality patterns to the uppermost Cretaceous Hell Creek Formation indicates that only NCMM and AM BB occur. Furthermore, NCMM BB are rare in the upper third of the Hell Creek. Near the K-T boundary, only AM BB are known. The absence of CMM and NCMM BB appears to be real reflecting a decrease in population levels of some dinosaurs prior to the K-T event. The absence of CMM suggests that the K-T event did not lead to an instantaneous extinction of dinosaurs. Nor was there a protracted die-off due to an asteroid impact winter, because no NCMM BB are known at or near the K-T boundary.

  13. Comprehensive photometric study of an extremely low mass ratio deep contact binary in the globular cluster M 4

    Science.gov (United States)

    Li, Kai; Hu, Shaoming; Chen, Xu; Guo, Difu

    2017-10-01

    A comprehensive photometric study and an investigation of the orbital period variation of V53 in the globular cluster M 4 are presented. The photometric study reveals that the mass ratio and the contact degree of V53 are q ˜ 0.078 and f ˜ 69%, respectively. The observed variation in the light curve can be explained by adjusting the spot parameters. V53 belongs to extreme mass ratio (q ≤ 0.25), deep contact (f ≥ 50%) binaries, and its mass ratio is close to the minimum mass ratio predicted by theoretical studies, making it a potential object for studying the evolution of binaries and the formation of blue stragglers and FK Com-type stars. The orbital period of V53 shows a long-term decrease at a rate of dp/dt = 5.89(±0.02) × 10-8 d yr-1. This secular period decrease may be caused by the combination of mass transfer from the more massive component to the less massive component and an angular momentum loss via magnetic braking. As this mass transfer and angular momentum loss continues, V53 will ultimately evolve into a single fast-rotation star. By studying the statistics of all the contact binaries in globular clusters that have been analyzed, we found a possible correlation between the contact degree and whether or not a contact binary is a blue straggler. A contact binary is likely to become a blue straggler when its fill-out factor is more than 46.25(±2.05)%. More samples should be introduced to confirm this preliminary result in the future.

  14. Genetic Analysis of High Bone Mass Cases from the BARCOS Cohort of Spanish Postmenopausal Women

    Science.gov (United States)

    Urreizti, Roser; Civit, Sergi; Cols, Neus; García-Giralt, Natàlia; Yoskovitz, Guy; Aranguren, Alvaro; Malouf, Jorge; Di Gregorio, Silvana; Río, Luís Del; Güerri, Roberto; Nogués, Xavier; Díez-Pérez, Adolfo; Grinberg, Daniel; Balcells, Susana

    2014-01-01

    The aims of the study were to establish the prevalence of high bone mass (HBM) in a cohort of Spanish postmenopausal women (BARCOS) and to assess the contribution of LRP5 and DKK1 mutations and of common bone mineral density (BMD) variants to a HBM phenotype. Furthermore, we describe the expression of several osteoblast-specific and Wnt-pathway genes in primary osteoblasts from two HBM cases. A 0.6% of individuals (10/1600) displayed Z-scores in the HBM range (sum Z-score >4). While no mutation in the relevant exons of LRP5 was detected, a rare missense change in DKK1 was found (p.Y74F), which cosegregated with the phenotype in a small pedigree. Fifty-five BMD SNPs from Estrada et al. [NatGenet 44:491-501,2012] were genotyped in the HBM cases to obtain risk scores for each individual. In this small group of samples, Z-scores were found inversely related to risk scores, suggestive of a polygenic etiology. There was a single exception, which may be explained by a rare penetrant genetic variant, counterbalancing the additive effect of the risk alleles. The expression analysis in primary osteoblasts from two HBM cases and five controls suggested that IL6R, DLX3, TWIST1 and PPARG are negatively related to Z-score. One HBM case presented with high levels of RUNX2, while the other displayed very low SOX6. In conclusion, we provide evidence of lack of LRP5 mutations and of a putative HBM-causing mutation in DKK1. Additionally, we present SNP genotyping and expression results that suggest additive effects of several genes for HBM. PMID:24736728

  15. Strategies for the chemical analysis of highly porous bone scaffolds using secondary ion mass spectrometry.

    Science.gov (United States)

    Wang, Daming; Poologasundarampillai, Gowsihan; van den Bergh, Wouter; Chater, Richard J; Kasuga, Toshihiro; Jones, Julian R; McPhail, David S

    2014-02-01

    Understanding the distribution of critical elements (e.g. silicon and calcium) within silica-based bone scaffolds synthesized by different methods is central to the optimization of these materials. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been used to determine this information due to its very high surface sensitivity and its ability to map all the elements and compounds in the periodic table with high spatial resolution. The SIMS image data can also be combined with depth profiles to construct three-dimensional chemical maps. However, the scaffolds have interconnected pore networks, which are very challenging structures for the SIMS technique. To overcome this problem two experimental methodologies have been developed. The first method involved the use of the focused ion beam technique to obtain clear images of the regions of interest and subsequently mark them by introducing fiducial marks; the samples were then analysed using the ToF-SIMS technique to yield the chemical analyses of the regions of interest. The second method involved impregnating the pores using a suitable reagent so that a flat surface could be achieved, and this was followed by secondary ion mapping and 3D chemical imaging with ToF-SIMS. The samples used in this work were sol-gel 70S30C foam and electrospun fibres and calcium-containing silica/gelatin hybrid scaffolds. The results demonstrate the feasibility of both these experimental methodologies and indicate that these methods can provide an opportunity to compare various artificial bone scaffolds, which will be of help in improving scaffold synthesis and processing routes. The techniques are also transferable to many other types of porous material.

  16. [Application of the discriminant analysis for the assessment of human somatotype using the long bones of extremities].

    Science.gov (United States)

    Grigor'eva, M A

    2004-01-01

    Measurements were made on the basis of the osteological collection of the chair for anthropology, Moscow State University (70 cases), and on the basis of a series of skeletons (10 cases) from among burial places of the Novospassk Monastery (males aged above 18-20). Eleven sizes of Martin program (length, diaphysis circumference and epiphysis width) were fixed onto the humerus, radial, femoral and shin bones. Simultaneously, the development of the osseous relief elements in the above bones (a total of 18 signs in each skeleton) was evaluated by Fedosova program. The data was processed by SPSS. Discriminative analysis was used as a basis to work out a diagnostic model that can be used to determine a somatotype by the humerus, radial and femoral bones. The classification accuracy is 75%. The method should be applied in those cases, when the appropriate bones are available. If the available combination of bones is different from the above, the routine method is recommended for use, i.e. determination of a somatotype by the skeleton massiveness.

  17. Time of flight secondary ion mass spectrometry of bone-Impact of sample preparation and measurement conditions.

    Science.gov (United States)

    Henss, Anja; Hild, Anne; Rohnke, Marcus; Wenisch, Sabine; Janek, Juergen

    2015-06-07

    Time of flight secondary ion mass spectrometry (ToF-SIMS) enables the simultaneous detection of organic and inorganic ions and fragments with high mass and spatial resolution. Due to recent technical developments, ToF-SIMS has been increasingly applied in the life sciences where sample preparation plays an eminent role for the quality of the analytical results. This paper focusses on sample preparation of bone tissue and its impact on ToF-SIMS analysis. The analysis of bone is important for the understanding of bone diseases and the development of replacement materials and new drugs for the cure of diseased bone. The main purpose of this paper is to find out which preparation process is best suited for ToF-SIMS analysis of bone tissue in order to obtain reliable and reproducible analytical results. The influence of the embedding process on the different components of bone is evaluated using principal component analysis. It is shown that epoxy resin as well as methacrylate based plastics (Epon and Technovit) as embedding materials do not infiltrate the mineralized tissue and that cut sections are better suited for the ToF-SIMS analysis than ground sections. In case of ground samples, a resin layer is smeared over the sample surface due to the polishing step and overlap of peaks is found. Beside some signals of fatty acids in the negative ion mode, the analysis of native, not embedded samples does not provide any advantage. The influence of bismuth bombardment and O2 flooding on the signal intensity of organic and inorganic fragments due to the variation of the ionization probability is additionally discussed. As C60 sputtering has to be applied to remove the smeared resin layer, its effect especially on the organic fragments of the bone is analyzed and described herein.

  18. Associations of breast-feeding patterns and introduction of solid foods with childhood bone mass: The Generation R Study.

    Science.gov (United States)

    van den Hooven, Edith H; Gharsalli, Mounira; Heppe, Denise H M; Raat, Hein; Hofman, Albert; Franco, Oscar H; Rivadeneira, Fernando; Jaddoe, Vincent W V

    2016-03-28

    Breast-feeding has been associated with later bone health, but results from previous studies are inconsistent. We examined the associations of breast-feeding patterns and timing of introduction of solids with bone mass at the age of 6 years in a prospective cohort study among 4919 children. We collected information about duration and exclusiveness of breast-feeding and timing of introduction of any solids with postnatal questionnaires. A total body dual-energy X-ray absorptiometry scan was performed at 6 years of age, and bone mineral density (BMD), bone mineral content (BMC), area-adjusted BMC (aBMC) and bone area (BA) were analysed. Compared with children who were ever breast-fed, those never breast-fed had lower BMD (-4·62 mg/cm2; 95 % CI -8·28, -0·97), BMC (-8·08 g; 95 % CI -12·45, -3·71) and BA (-7·03 cm2; 95 % CI -12·55, -1·52) at 6 years of age. Among all breast-fed children, those who were breast-fed non-exclusively in the first 4 months had higher BMD (2·91 mg/cm2; 95 % CI 0·41, 5·41) and aBMC (3·97 g; 95 % CI 1·30, 6·64) and lower BA (-4·45 cm2; 95 % CI -8·28, -0·61) compared with children breast-fed exclusively for at least 4 months. Compared with introduction of solids between 4 and 5 months, introduction feeding compared with never breast-feeding is associated with higher bone mass in 6-year-old children, but exclusive breast-feeding for 4 months or longer was not positively associated with bone outcomes.

  19. Nrf2 regulates mass accrual and the antioxidant endogenous response in bone differently depending on the sex and age

    Science.gov (United States)

    Pellegrini, Gretel Gisela; Cregor, Meloney; McAndrews, Kevin; Morales, Cynthya Carolina; McCabe, Linda Doyle; McCabe, George P.; Peacock, Munro; Burr, David; Weaver, Connie; Bellido, Teresita

    2017-01-01

    Accumulation of reactive oxygen species (ROS) is an important pathogenic mechanism underling the loss of bone mass and strength with aging and other conditions leading to osteoporosis. The transcription factor erythroid 2-related factor2 (Nrf2) plays a central role in activating the cellular response to ROS. Here, we examined the endogenous response of bone regulated by Nrf2, and its relationship with bone mass and architecture in the male and female murine skeleton. Young (3 month-old) and old (15 month-old) Nrf2 knockout (KO) mice of either sex exhibited the expected reduction in Nrf2 mRNA expression compared to wild type (WT) littermates. Nrf2 deletion did not lead to compensatory increase in Nrf1 or Nrf3, other members of this transcription factor family; and instead, Nrf1 expression was lower in KO mice. Compared to the respective WT littermate controls, female KO mice, young and old, exhibited lower expression of both detoxifying and antioxidant enzymes; young male KO mice, displayed lower expression of detoxifying enzymes but not antioxidant enzymes; and old male KO mice showed no differences in either detoxifying or antioxidant enzymes. Moreover, old male WT mice exhibited lower Nrf2 levels, and consequently lower expression of both detoxifying and antioxidant enzymes, compared to old female WT mice. These endogenous antioxidant responses lead to delayed rate of bone acquisition in female KO mice and higher bone acquisition in male KO mice as quantified by DXA and μCT, demonstrating that Nrf2 is required for full bone accrual in the female skeleton but unnecessary and even detrimental in the male skeleton. Therefore, Nrf2 regulates the antioxidant endogenous response and bone accrual differently depending on sex and age. These findings suggest that therapeutic interventions that target Nrf2 could be developed to enhance the endogenous antioxidant response in a sex- and age-selective manner. PMID:28152064

  20. Invariant-Mass Spectroscopy of Extremely Neutron-Rich Nuclei with SAMURAI at RIBF

    Science.gov (United States)

    Kondo, Yosuke; Nakamura, Takashi; Achouri, N. Lynda; Aumann, Thomas; Baba, Hidetada; Delaunay, Franck; Doornenbal, Pieter; Fukuda, Naoki; Gibelin, Julien; Hwang, Jongwon; Inabe, Naohito; Isobe, Tadaaki; Kameda, Daisuke; Kanno, Daiki; Kim, Sunji; Kobayashi, Nobuyuki; Kobayashi, Toshio; Kubo, Toshiyuki; Leblond, Sylvain; Lee, Jenny; Marqués, F. Miguel; Minakata, Ryogo; Motobayashi, Tohru; Murai, Daichi; Murakami, Tetsuya; Muto, Kotomi; Nakashima, Tomohiro; Nakatsuka, Noritsugu; Navin, Alahari; Nishi, Seijiro; Ogoshi, Shun; Orr, Nigel A.; Otsu, Hideaki; Sato, Hiromi; Satou, Yoshiteru; Shimizu, Yohei; Suzuki, Hiroshi; Takahashi, Kento; Takeda, Hiroyuki; Takeuchi, Satoshi; Tanaka, Ryuki; Togano, Yasuhiro; Tuff, Adam G.; Vandebrouck, Marine; Yoneda, Ken-ichiro

    A first experimental campaign for three physics programs using a spectrometer SAMURAI, which is newly constructed at RIBF at RIKEN, was performed in May 2012. In this campaign, the unbound nuclei 25O and 26O produced by one-proton removal reactions at ˜200 MeV/nucleon were investigated by means of invariant mass method. High statistics data compared with previous experiments could be obtained together with good particle identification resolution for outgoing heavy ion. Preliminary results show high performance of the SAMURAI spectrometer combined with high intense RI beams provided by RIBF.

  1. Planetary protection in the extreme environments of low-mass stars

    CERN Document Server

    Vidotto, A A; Morin, J; Donati, J -F; Lang, P; Russell, A J B

    2013-01-01

    Recent results showed that the magnetic field of M-dwarf (dM) stars, currently the main targets in searches for terrestrial planets, is very different from the solar one, both in topology as well as in intensity. In particular, the magnetised environment surrounding a planet orbiting in the habitable zone (HZ) of dM stars can differ substantially to the one encountered around the Earth. These extreme magnetic fields can compress planetary magnetospheres to such an extent that a significant fraction of the planet's atmosphere may be exposed to erosion by the stellar wind. Using observed surface magnetic maps for a sample of 15 dM stars, we investigate the minimum degree of planetary magnetospheric compression caused by the intense stellar magnetic fields. We show that hypothetical Earth-like planets with similar terrestrial magnetisation (~1G) orbiting at the inner (outer) edge of the HZ of these stars would present magnetospheres that extend at most up to 6.1 (11.7) planetary radii. To be able to sustain an E...

  2. ZP2307, a novel, cyclic PTH(1-17) analog that augments bone mass in ovariectomized rats

    DEFF Research Database (Denmark)

    Neerup, Trine Skovlund Ryge; Stahlhut, Martin; Petersen, Jørgen S

    2011-01-01

    Daily injections of human parathyroid hormone (1-34), hPTH(1-34), provide a highly effective treatment option for severe osteoporosis. However, PTH analogs shorter than 28 amino acids do not retain any bone augmenting potential. Here, we present ZP2307 ([Ac₅c¹, Aib³, Leu⁸, Gln¹⁰, Har¹¹, Ala¹², Trp......¹⁴, Asp¹⁷]PTH(1-17)-NH₂), a novel, chemically modified and cyclized hPTH(1-17) analog, that augments bone mass in ovariectomized, osteopenic rats. Subcutaneous administration of this structurally constrained, K¹³-D¹⁷ side-chain-to-side-chain cyclized peptide reversed bone loss and increased bone...... mineral density (BMD) up to or above baseline levels in rat long bones and vertebrae. Highly significant effects of ZP2307 were achieved at doses of 40-320 nmol/kg. Micro-CT and histomorphometric analyses showed that ZP2307 improved quantitative and qualitative parameters of bone structure. Biomechanical...

  3. Bone mass and breast milk calcium concentration are associated with vitamin D receptor gene polymorphisms in adolescent mothers.

    Science.gov (United States)

    Bezerra, Flávia F; Cabello, Giselda M K; Mendonça, Laura M C; Donangelo, Carmen M

    2008-02-01

    Lactation-associated bone loss has been reported in adolescent mothers. Polymorphisms in the vitamin D receptor (VDR) gene may contribute to differences in the physiologic skeletal response to lactation in these mothers. We evaluated the influence of VDR gene polymorphisms ApaI, BsmI, and TaqI on bone mass, bone and calcium-related hormones, and breast milk calcium of lactating adolescents with habitually low calcium intake. Total body bone mineral content (TBMC), total body bone mineral density (TBMD), lumbar spine BMD (LSBMD), serum hormones [intact parathyroid hormone (iPTH), 25-hydroxyvitamin D, insulin-like growth factor-I (IGF1), prolactin, and estradiol), and breast milk calcium were measured in 40 lactating Brazilian adolescents (15-18 y), and compared by VDR genotype subgroups after adjustment for calcium intake and postmenarcheal and lactational periods. TBMD and LSBMD Z scores were -0.55 +/- 1.01 and -1.15 +/- 1.48, respectively. LSBMD was higher (21%; P milk calcium and serum iPTH were higher (24 and 80%, respectively; P milk calcium are significantly associated with VDR genotypes in lactating Brazilian adolescents. Those with aa and tt genotypes had a better bone status and those with bb genotype had greater breast milk calcium.

  4. Feeding flaxseed oil but not secoisolariciresinol diglucoside results in higher bone mass in healthy rats and rats with kidney disease.

    Science.gov (United States)

    Weiler, H A; Kovacs, H; Nitschmann, E; Bankovic-Calic, N; Aukema, H; Ogborn, M

    2007-05-01

    Flaxseed's oil and lignan, secoisolariciresinol diglucoside (SDG), are implicated in attainment of health and treatment of renal injury and osteoporosis. To test for these benefits, weanling Han:SPRD-cy rats (n=171) with or without kidney disease were randomized to diets made with either corn oil or flaxseed oil and with or without SDG for 12 weeks. In females, weight was lower with the SDG diet. In males fed flaxseed oil, lean mass was higher and fat % was lower. In both sexes, fat % was lower in diseased rats. Bone mineral content (BMC) and density were higher in rats fed flaxseed oil and lower in diseased rats, additionally; BMC was lower in SDG-supplemented females. The benefit of flaxseed oil on body composition is sex specific but the effect on bone mass is not. Lastly, reduced weight due to early rat kidney disease is not due to loss of lean body mass.

  5. 儿童双骨肢体单骨骨折对关节的影响%Influence on Joints Due to Fracture of Single Bone on Double Bone Extremities in Children

    Institute of Scientific and Technical Information of China (English)

    俞志涛; 王承武; 范源

    1997-01-01

    Objective:To observe the overgrowth after the fracture of a single bone in double bone extremities in children.Methods:179 cases of forearm fracture and 123 of lower leg fracture (excluding Monteggia fracture,Galeazzi fracture or physeal injuries)were reviewed.The time of follow-up was 5~8 years(mean 7.5 years).Comparative assessments of bilateral extremities on X-ray examination included length of ulna and radius,radioulnar angle,anteversion of the radius,radiocapitular line,position of the capitellium,length of the tibia and fibula,and anteroposteriorproject of the ankle.Ranges of motion of the wrist,elbow,forearm and ankle were examined.Results:Overgrowth of affected bones With 2~4 mm in length were found only in 4 cases of forearm fracture and in 7 cases of lower leg fracture.Conclusions:In most cases of fracture of singlebone on double bone extremities,overgrowth of affected bone has been rarely observed.%目的:为了观察儿童双骨肢体单骨骨折后的过度生长.方法:对前臂单骨骨折179例(不包括孟氏骨折、盖氏骨折及骨骺损伤),小腿单骨骨折123例(不包括骨骺损伤),进行了5~6年的随访,平均7.5年.对比测量了双侧X线片中的尺、桡骨长度、胫腓骨长度、桡尺角、桡骨内倾角、桡骨头线、肱骨小头的位置以及踝关节正位片,并对腕、肘关节、踝关节活动进行了对比.结果:前臂有4例,小腿有7例较对侧长2~4 mm.前臂、腕、肘关节及踝关节活动无异常.结论:前臂是双骨均衡支撑肢体,小腿虽以胫骨负重为主,但单骨骨折后另一骨同样可起支撑作用,因此均不会出现明显的过度生长.

  6. The ISLANDS project I: Andromeda XVI, An Extremely Low Mass Galaxy not Quenched by Reionization

    CERN Document Server

    Monelli, Matteo; Bernard, Edouard J; Gallart, Carme; Skillman, Evan D; Weisz, Daniel R; Dolphin, Andrew E; Hidalgo, Sebastian L; Cole, Andrew A; Martin, Nicolas F; Aparicio, Antonio; Cassisi, Santi; Boylan-Kolchin, Michael; Mayer, Lucio; McConnachie, Alan; McQuinn, Kristen B W; Navarro, Julio F

    2016-01-01

    Based on data aquired in 13 orbits of HST time, we present a detailed evolutionary history of the M31 dSph satellite Andromeda XVI, including its life-time star formation history, the spatial distribution of its stellar populations, and the properties of its variable stars. And XVI is characterized by prolonged star formation activity from the oldest epochs until star formation was quenched ~6 Gyr ago, and, notably, only half of the mass in stars of And XVI was in place 10 Gyr ago. And XVI appears to be a low mass galaxy for which the early quenching by either reionization or starburst feedback seems highly unlikely, and thus, is most likely due to an environmental effect (e.g., an interaction), possibly connected to a late infall in the densest regions of the Local Group. Studying the star formation history as a function of galactocentric radius, we detect a mild gradient in the star formation history: the star formation activity between 6 and 8 Gyr ago is significantly stronger in the central regions than i...

  7. The butterfly effect in the extreme-mass ratio inspiral problem

    CERN Document Server

    Amaro-Seoane, Pau; Cuadra, Jorge; Armitage, Philip J

    2011-01-01

    Measurements of gravitational waves from the inspiral of a stellar-mass compact object into a massive black hole (MBH) are unique probes to test General Relativity (GR) and MBH properties, as well as the stellar distribution about these holes in galactic nuclei. Current data analysis techniques can provide us with parameter estimation with very narrow errors. However, an EMRI is not a two-body problem, since other stellar bodies orbiting nearby will influence the capture orbit. Any deviation from the isolated inspiral of the binary will induce a small, though observable deviation from the idealised waveform which could be misinterpreted as a failure of GR. Based on conservative analysis of mass segregation in a Milky Way like nucleus, we estimate that the possibility that a star has a semi-major axis comparable to that of the EMRI is non-negligible. This star introduces an observable perturbation in the orbit in the case in which we consider only loss of energy via gravitational radiation at periapsis. When c...

  8. X-ray bursts at extreme mass accretion rates from GX 17+2

    CERN Document Server

    Kuulkers, E; Van der Klis, M; Lewin, W H G; Méndez, M

    2002-01-01

    (abridged version) We report on ten X-ray bursts from GX 17+2 in RXTE data in 1996-2000. Three bursts were short in duration (~10 s), whereas the others lasted for ~6-25 min. Five of the long bursts showed evidence for radius expansion of the neutron star photosphere. No correlations of the burst properties with respect to the persistent X-ray spectral properties are seen, suggesting no correlation with inferred persistent mass accretion rate. The presence of short bursts in GX 17+2 and other bright X-ray sources, i.e. Cyg X-2, GX 3+1 and GX 13+1, as well as the ABSENCE of bursts in the bright X-ray sources Sco X-1, GX 5-1, GX 340+0, GX 349+2, GX 9+1 and GX 9+9 is not accounted for in the current X-ray bursts theories at the high mass accretion rates encountered in these sources. We find that in contrast to previous suggestions the persistent black-body emission does NOT arise from the same site as the burst emission. The black-body component of the persistent emission is consistent with arising in an expande...

  9. Effects of Habitual Physical Activity and Fitness on Tibial Cortical Bone Mass, Structure and Mass Distribution in Pre-pubertal Boys and Girls: The Look Study.

    Science.gov (United States)

    Duckham, Rachel L; Rantalainen, Timo; Ducher, Gaele; Hill, Briony; Telford, Richard D; Telford, Rohan M; Daly, Robin M

    2016-07-01

    Targeted weight-bearing activities during the pre-pubertal years can improve cortical bone mass, structure and distribution, but less is known about the influence of habitual physical activity (PA) and fitness. This study examined the effects of contrasting habitual PA and fitness levels on cortical bone density, geometry and mass distribution in pre-pubertal children. Boys (n = 241) and girls (n = 245) aged 7-9 years had a pQCT scan to measure tibial mid-shaft total, cortical and medullary area, cortical thickness, density, polar strength strain index (SSIpolar) and the mass/density distribution through the bone cortex (radial distribution divided into endo-, mid- and pericortical regions) and around the centre of mass (polar distribution). Four contrasting PA and fitness groups (inactive-unfit, inactive-fit, active-unfit, active-fit) were generated based on daily step counts (pedometer, 7-days) and fitness levels (20-m shuttle test and vertical jump) for boys and girls separately. Active-fit boys had 7.3-7.7 % greater cortical area and thickness compared to inactive-unfit boys (P < 0.05), which was largely due to a 6.4-7.8 % (P < 0.05) greater cortical mass in the posterior-lateral, medial and posterior-medial 66 % tibial regions. Cortical area was not significantly different across PA-fitness categories in girls, but active-fit girls had 6.1 % (P < 0.05) greater SSIpolar compared to inactive-fit girls, which was likely due to their 6.7 % (P < 0.05) greater total bone area. There was also a small region-specific cortical mass benefit in the posterior-medial 66 % tibia cortex in active-fit girls. Higher levels of habitual PA-fitness were associated with small regional-specific gains in 66 % tibial cortical bone mass in pre-pubertal children, particularly boys.

  10. Vascular calcification of the lower extremities demonstrated by Tc-99m MDP bone scintigraphy in a patient with diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Seok Tae; Sohn, Myung Hee [Chonbuk National University Medical School, Chonju, l (Korea, Republic of)

    2001-06-01

    The femoral vessels are sometimes visualized on bone scintigraphy. This is almost always caused by calcification of the femoral artery associated with atherosclerotic changes of the arterial wall. Vascular calcification is frequently seen in the elderly and in diabetics. A 78 year old woman was admitted for non-insulin dependent diabetes mellitus. In this patient with diabetes mellitus, tibial arteries as well as femoral arteries were visualized onTc-99m MDP bone scintigraphy in contrast with visualization of femoral artery alone observed in the elderly.

  11. A comparison of fine-needle aspiration, core biopsy, and surgical biopsy in the diagnosis of extremity soft tissue masses.

    Science.gov (United States)

    Kasraeian, Sina; Allison, Daniel C; Ahlmann, Elke R; Fedenko, Alexander N; Menendez, Lawrence R

    2010-11-01

    Biopsy tissue can be obtained through a fine needle, a wider coring needle, or through an open surgical incision. Though much literature exists regarding the diagnostic yield of these techniques individually, none compare accuracy of diagnosis in the same mass. We asked how the diagnostic accuracy of fine-needle aspiration, core biopsy, and open surgical biopsy compare in regard to identifying malignancy, establishing the exact diagnosis, and guiding the appropriate treatment of soft tissue masses. We prospectively studied 57 patients with palpable extremity soft tissue masses, performing fine-needle aspiration, followed by core biopsy, followed by surgical biopsy of the same mass. Open surgical biopsy was 100% accurate on all accounts. With regard to determining malignancy, fine-needle aspiration and core biopsy had 79.17% and 79.2% sensitivity, 72.7% and 81.8% specificity, 67.9% and 76% positive predictive value, 82.8% and 84.4% negative predictive value, and an overall accuracy of 75.4% and 80.7%, respectively. In regard to determining exact diagnosis, fine-needle aspiration had a 33.3% accuracy and core biopsy had a 45.6% accuracy. With regard to eventual treatment, fine-needle aspiration was 38.6% accurate and core biopsy was 49.1% accurate. In soft tissue mass diagnosis, core biopsy is more accurate than fine-needle aspiration on all accounts, and open biopsy is more accurate than both in determining malignancy, establishing the exact diagnosis, and the guiding appropriate treatment.

  12. Extremes in body mass index affect overall survival in women with cervical cancer.

    Science.gov (United States)

    Clark, Leslie H; Jackson, Amanda L; Soo, Adrianne E; Orrey, Danielle C; Gehrig, Paola A; Kim, Kenneth H

    2016-06-01

    To examine the effect of BMI on pathologic findings, cancer recurrence and survival in cervical cancer patients. A retrospective cohort study of cervical cancer patients treated from July 2000 to March 2013 was performed. BMI was calculated, and patients were classified by BMI. The primary outcome was overall survival (OS). Secondary outcomes included stage, histopathology, disease-specific survival (DSS) and recurrence free survival (RFS). Kaplan-Meier survival curves were generated and compared using Cox proportional hazard ratios. Of 632 eligible patients, 24 (4%) were underweight, 191 (30%) were normal weight, 417 (66%) were overweight/obese. There was no difference in age (p=0.91), stage at presentation (p=0.91), grade (p=0.46), or histology (p=0.76) between weight categories. There were fewer White patients in the underweight (54%) and overweight/obese (58%) groups compared to the normal weight (71%) group (p=0.04). After controlling for prognostic factors, underweight and overweight/obese patients had worse median RFS than normal weight patients (7.6 v 25.0months, p=0.01 and 20.3 v 25.0months, p=0.03). Underweight patients also had worse OS (10.4 v 28.4months, p=0.031) and DSS (13.8 v 28.4months, p=0.04) compared to normal weight patients. Overweight/obese patients had worse OS than normal weight patients (22.2 v 28.4months, p=0.03) and a trend toward worse DSS (21.9 v 28.4months, p=0.09). Both extremes of weight (underweight and overweight/obesity) were associated with worse survival in patients with cervical cancer. Optimizing weight in cervical cancer patients may improve outcomes in these patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Modeling the effect of levothyroxine therapy on bone mass density in postmenopausal women: a different approach leads to new inference

    Directory of Open Access Journals (Sweden)

    Tavangar Seyed

    2007-06-01

    Full Text Available Abstract Background The diagnosis, treatment and prevention of osteoporosis is a national health emergency. Osteoporosis quietly progresses without symptoms until late stage complications occur. Older patients are more commonly at risk of fractures due to osteoporosis. The fracture risk increases when suppressive doses of levothyroxine are administered especially in postmenopausal women. The question is; "When should bone mass density be tested in postmenopausal women after the initiation of suppressive levothyroxine therapy?". Standard guidelines for the prevention of osteoporosis suggest that follow-up be done in 1 to 2 years. We were interested in predicting the level of bone mass density in postmenopausal women after the initiation of suppressive levothyroxine therapy with a novel approach. Methods The study used data from the literature on the influence of exogenous thyroid hormones on bone mass density. Four cubic polynomial equations were obtained by curve fitting for Ward's triangle, trochanter, spine and femoral neck. The behaviors of the models were investigated by statistical and mathematical analyses. Results There are four points of inflexion on the graphs of the first derivatives of the equations with respect to time at about 6, 5, 7 and 5 months. In other words, there is a maximum speed of bone loss around the 6th month after the start of suppressive L-thyroxine therapy in post-menopausal women. Conclusion It seems reasonable to check bone mass density at the 6th month of therapy. More research is needed to explain the cause and to confirm the clinical application of this phenomenon for osteoporosis, but such an approach can be used as a guide to future experimentation. The investigation of change over time may lead to more sophisticated decision making in a wide variety of clinical problems.

  14. THE ISLANDS PROJECT. I. ANDROMEDA XVI, AN EXTREMELY LOW MASS GALAXY NOT QUENCHED BY REIONIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Monelli, Matteo; Martínez-Vázquez, Clara E.; Gallart, Carme; Hidalgo, Sebastian L.; Aparicio, Antonio [Instituto de Astrofísica de Canarias, La Laguna, Tenerife (Spain); Bernard, Edouard J. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Skillman, Evan D.; McQuinn, Kristen B. W. [Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street, SE Minneapolis, MN, 55455 (United States); Weisz, Daniel R. [Astronomy Department, Box 351580, University of Washington, Seattle, WA, 98195 (United States); Dolphin, Andrew E. [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85706 (United States); Cole, Andrew A. [School of Physical Sciences, University of Tasmania, Private Bag 37, Hobart 7005, TAS (Australia); Martin, Nicolas F. [Observatoire astronomique de Strasbourg, Universite de Strasbourg, CNRS, UMR 7550, 11 rue de l’Universite, F-67000 Strasbourg (France); Cassisi, Santi [INAF-Osservatorio Astronomico di Collurania, Teramo (Italy); Boylan-Kolchin, Michael [INAF–Osservatorio Astronomico di Teramo, via M. Maggini, 64100 Teramo (Italy); Mayer, Lucio [Department of Astronomy, The University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712 (United States); McConnachie, Alan [Herzberg Astronomy and Astrophysics, National Research Council Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Navarro, Julio F., E-mail: monelli@iac.es [Department of Physics and Astronomy, University of Victoria, P.O. Box 1700, STN CSC, Victoria, BC V8W 3P6 (Canada)

    2016-03-10

    Based on data aquired in 13 orbits of Hubble Space Telescope time, we present a detailed evolutionary history of the M31 dSph satellite Andromeda XVI, including its lifetime star formation history (SFH), the spatial distribution of its stellar populations, and the properties of its variable stars. And XVI is characterized by prolonged star formation activity from the oldest epochs until star formation was quenched ∼6 Gyr ago, and, notably, only half of the mass in stars of And XVI was in place 10 Gyr ago. And XVI appears to be a low-mass galaxy for which the early quenching by either reionization or starburst feedback seems highly unlikely, and thus it is most likely due to an environmental effect (e.g., an interaction), possibly connected to a late infall in the densest regions of the Local Group. Studying the SFH as a function of galactocentric radius, we detect a mild gradient in the SFH: the star formation activity between 6 and 8 Gyr ago is significantly stronger in the central regions than in the external regions, although the quenching age appears to be the same, within 1 Gyr. We also report the discovery of nine RR Lyrae (RRL) stars, eight of which belong to And XVI. The RRL stars allow a new estimate of the distance, (m − M){sub 0} = 23.72 ± 0.09 mag, which is marginally larger than previous estimates based on the tip of the red giant branch.

  15. Distribution of fat, non-osseous lean and bone mineral mass in international Rugby Union and Rugby Sevens players.

    Science.gov (United States)

    Higham, D G; Pyne, D B; Anson, J M; Dziedzic, C E; Slater, G J

    2014-06-01

    Differences in the body composition of international Rugby Union and Rugby Sevens players, and between players of different positions are poorly understood. The purpose of this study was to examine differences in the quantity and regional distribution of fat, non-osseous lean and bone mineral mass between playing units in Rugby Union and Rugby Sevens. Male Rugby Union (n=21 forwards, 17 backs) and Rugby Sevens (n=11 forwards, 16 backs) players from the Australian national squads were measured using dual-energy X-ray absorptiometry. The digital image of each player was partitioned into anatomical regions including the arms, legs, trunk, and android and gynoid regions. Compared with backs, forwards in each squad were heavier and exhibited higher absolute regional fat (Union 43-67%; ±~17%, range of % differences; ±~95% confidence limits (CL); Sevens 20-26%; ±~29%), non-osseous lean (Union 14-22%; ±~5.8%; Sevens 6.9-8.4%; ±~6.6%) and bone mineral (Union 12-26%; ±~7.2%; Sevens 5.0-11%; ±~7.2%) mass. When tissue mass was expressed relative to regional mass, differences between Rugby Sevens forwards and backs were mostly unclear. Rugby Union forwards had higher relative fat mass (1.7-4.7%; ±~1.9%, range of differences; ±~95% CL) and lower relative non-osseous lean mass (-4.2 to -1.8%; ±~1.8%) than backs in all body regions. Competing in Rugby Union or Rugby Sevens characterized the distribution of fat and non-osseous lean mass to a greater extent than a player's positional group, whereas the distribution of bone mineral mass was associated more with a player's position. Differences in the quantity and distribution of tissues appear to be related to positional roles and specific demands of competition in Rugby Union and Rugby Sevens.

  16. The role of fat and lean mass in bone loss in older men: findings from the CHAMP study.

    Science.gov (United States)

    Bleicher, Kerrin; Cumming, Robert G; Naganathan, Vasikaran; Travison, Thomas G; Sambrook, Philip N; Blyth, Fiona M; Handelsman, David J; Le Couteur, David G; Waite, Louise M; Creasey, Helen M; Seibel, Markus J

    2011-12-01

    Weight loss is associated with bone loss; however, it is unclear whether loss of fat or loss of lean body mass plays the key role in this relationship. The aim of this longitudinal analysis was to clarify the relationship between hip BMD, hip BMC and whole body BMC with changes in fat and lean tissue mass in older men. The Concord Health and Aging in Men Project (CHAMP) is a population-based study in Sydney, Australia, involving 1705 men aged 70-97 years. Bone mineral density (BMD) of the total hip, and bone mineral content (BMC) of the hip and whole body (WB), lean mass and fat mass were measured with Dual X-ray Absorptiometry (DXA). Multivariate linear regression models were used to assess relationships. Over 2.2 years of follow-up, 368(33%) men lost at least 2% of their body weight, which included a mean loss of 0.8 kg/year of lean body mass and 0.9 kg/year of fat body mass. Fat loss was strongly associated with BMD loss in men who lost weight. As a group, weight losers lost 1.0% of hip BMD annually compared to 0.2% in men who gained weight, with each kilo of fat loss associated with 0.6%/year hip BMD loss (ploss in weight losers, however, lean mass change was associated with BMD change in men who gained weight (0.3% hip BMD increase per kilo increase of lean mass pfat plays an important role in this relationship, which may reflect the additional metabolic function of adipose tissue. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Dual-energy imaging of bone marrow edema on a dedicated multi-source cone-beam CT system for the extremities

    Science.gov (United States)

    Zbijewski, W.; Sisniega, A.; Stayman, J. W.; Thawait, G.; Packard, N.; Yorkston, J.; Demehri, S.; Fritz, J.; Siewerdsen, J. H.

    2015-03-01

    Purpose: Arthritis and bone trauma are often accompanied by bone marrow edema (BME). BME is challenging to detect in CT due to the overlaying trabecular structure but can be visualized using dual-energy (DE) techniques to discriminate water and fat. We investigate the feasibility of DE imaging of BME on a dedicated flat-panel detector (FPD) extremities cone-beam CT (CBCT) with a unique x-ray tube with three longitudinally mounted sources. Methods: Simulations involved a digital BME knee phantom imaged with a 60 kVp low-energy beam (LE) and 105 kVp high-energy beam (HE) (+0.25 mm Ag filter). Experiments were also performed on a test-bench with a Varian 4030CB FPD using the same beam energies as the simulation study. A three-source configuration was implemented with x-ray sources distributed along the longitudinal axis and DE CBCT acquisition in which the superior and inferior sources operate at HE (and collect half of the projection angles each) and the central source operates at LE. Three-source DE CBCT was compared to a double-scan, single-source orbit. Experiments were performed with a wrist phantom containing a 50 mg/ml densitometry insert submerged in alcohol (simulating fat) with drilled trabeculae down to ~1 mm to emulate the trabecular matrix. Reconstruction-based three-material decomposition of fat, soft tissue, and bone was performed. Results: For a low-dose scan (36 mAs in the HE and LE data), DE CBCT achieved combined accuracy of ~0.80 for a pattern of BME spherical lesions ranging 2.5 - 10 mm diameter in the knee phantom. The accuracy increased to ~0.90 for a 360 mAs scan. Excellent DE discrimination of the base materials was achieved in the experiments. Approximately 80% of the alcohol (fat) voxels in the trabecular phantom was properly identified both for single and 3-source acquisitions, indicating the ability to detect edemous tissue (water-equivalent plastic in the body of the densitometry insert) from the fat inside the trabecular matrix

  18. Alfacalcidol improves muscle power, muscle function and balance in elderly patients with reduced bone mass.

    Science.gov (United States)

    Schacht, E; Ringe, Johann D

    2012-01-01

    We investigated the effect of daily therapy with 1 mcg alfacalcidol (Doss(®)-TEVA/AWD-pharma) on muscle power, muscle function, balance performance and fear of falls in an open, multi-centered, uncontrolled, prospective study on a cohort of patients with reduced bone mass. Among the 2,097 participants, 87.1% were post-menopausal women and 12.9% were men. Mean age was 74.8 years and mean body mass index (BMI) 26.3 kg/m². A total of 75.3% of the study population had osteoporosis, 81% a diagnosis of "increased risk of falls" and 70.1% had a creatinine clearance (CrCl) of muscle function and muscle power tests at onset and after 3 and 6 months: the timed up and go test (TUG) and the chair rising test (CRT). At baseline and after 6 months, participants performed the tandem gait test (TGT) and filled out a questionnaire evaluating fear of falling. Successful performance in the muscle tests is associated with a significantly lower risk of falls and non-vertebral fractures in elderly patients (successful test performance: TUG ≤ 10 s (sec), CRT ≤ 10 s, TGT ≥ 8 steps). A significant improvement in the performance of the two muscle tests was proved already after 3 months of treatment with alfacalcidol and further increased by the end of the therapeutic intervention. There were significant increases in the number of participants able to successfully perform the tests: 24.6% at baseline and 46.3% at the end of trial for the TUG (P muscle power, muscle function and balance and reduces fear of falls. The significant improvement in the three muscle and balance tests and fear of falls may have a preventative effect on falls and fractures. We suggest that the quantitative risk tests used in this study could be reliable surrogate parameters for the risk of falls and fractures in elderly patients.

  19. Genome-wide association study using extreme truncate selection identifies novel genes affecting bone mineral density and fracture risk

    NARCIS (Netherlands)

    E.L. Duncan (Emma); P. Danoy (Patrick); J.P. Kemp (John); P.J. Leo (Paul); E. McCloskey (Eugene); G.C. Nicholson (Geoffrey); R. Eastell (Richard); R.L. Prince (Richard); J.A. Eisman (John); G. Jones (Graeme); P.N. Sambrook (Philip); I.R. Reid (Ian); E.M. Dennison (Elaine); J. Wark (John); J.B. Richards (Brent); A.G. Uitterlinden (André); T.D. Spector (Timothy); C. Esapa (Chris); R.D. Cox (Roger); S.D.M. Brown (Steve); R.V. Thakker (Rajesh); K.A. Addison (Kathryn); L.A. Bradbury (Linda); J.R. Center (Jacqueline); C. Cooper (Cyrus); C. Cremin (Catherine); K. Estrada Gil (Karol); D. Felsenberg (Dieter); C.-C. Glüer (Claus-); J. Hadler (Johanna); M.J. Henry (Margaret); A. Hofman (Albert); M.A. Kotowicz (Mark); J. Makovey (Joanna); S.C. Nguyen (Sing); J.A. Pasco (Julie); K. Pryce (Karena); F. Rivadeneira Ramirez (Fernando); C. Roux (Christian); K. Stefansson (Kari); U. Styrkarsdottir (Unnur); G. Thorleifsson (Gudmar); R. Tichawangana (Rumbidzai); D.M. Evans (David)

    2011-01-01

    textabstractOsteoporotic fracture is a major cause of morbidity and mortality worldwide. Low bone mineral density (BMD) is a major predisposing factor to fracture and is known to be highly heritable. Site-, gender-, and age-specific genetic effects on BMD are thought to be significant, but have larg

  20. Mx1-cre mediated Rgs12 conditional knockout mice exhibit increased bone mass phenotype.

    Science.gov (United States)

    Yang, Shuying; Li, Yi-Ping; Liu, Tongjun; He, Xiaoning; Yuan, Xue; Li, Chunyi; Cao, Jay; Kim, Yunjung

    2013-03-01

    Regulators of G-protein Signaling (Rgs) proteins are the members of a multigene family of GTPase-accelerating proteins (GAP) for the Galpha subunit of heterotrimeric G-proteins. Rgs proteins play critical roles in the regulation of G protein couple receptor (GPCR) signaling in normal physiology and human diseases such as cancer, heart diseases, and inflammation. Rgs12 is the largest protein of the Rgs protein family. Some in vitro studies have demonstrated that Rgs12 plays a critical role in regulating cell differentiation and migration; however its function and mechanism in vivo is largely unknown. Here, we generated a floxed Rgs12 allele (Rgs12(flox/flox) ) in which the exon 2, containing both PDZ and PTB_PID domains of Rgs12, was flanked with two loxp sites. By using the inducible Mx1-cre and Poly I:C system to specifically delete Rgs12 at postnatal 10 days in interferon-responsive cells including monocyte and macrophage cells, we found that Rgs12 mutant mice had growth retardation with the phenotype of increased bone mass. We further found that deletion of Rgs12 reduced osteoclast numbers and had no significant effect on osteoblast formation. Thus, Rgs12(flox/flox) conditional mice provide a valuable tool for in vivo analysis of Rgs12 function and mechanism through time- and cell-specific deletion of Rgs12.

  1. Gravitational waves from extreme mass-ratio inspirals in Dynamical Chern-Simons gravity

    CERN Document Server

    Pani, Paolo; Gualtieri, Leonardo

    2011-01-01

    Dynamical Chern-Simons gravity is an interesting extension of General Relativity, which finds its way in many different contexts, including string theory, cosmological settings and loop quantum gravity. In this theory, the gravitational field is coupled to a scalar field by a parity-violating term, which gives rise to characteristic signatures. Here we investigate how Chern-Simons gravity would affect the quasi-circular inspiralling of a small, stellar-mass object into a large non-rotating supermassive black hole, and the accompanying emission of gravitational and scalar waves. We find the relevant equations describing the perturbation induced by the small object, and we solve them through the use of Green's function techniques. Our results show that for a wide range of coupling parameters, the Chern-Simons coupling gives rise to an increase in total energy flux, which translates into a fewer number of gravitational-wave cycles over a certain bandwidth. For space-based gravitational-wave detectors such as LIS...

  2. Gravitational waves from extreme mass-ratio inspirals in dynamical Chern-Simons gravity

    Science.gov (United States)

    Pani, Paolo; Cardoso, Vitor; Gualtieri, Leonardo

    2011-05-01

    Dynamical Chern-Simons gravity is an interesting extension of general relativity, which finds its way in many different contexts, including string theory, cosmological settings, and loop quantum gravity. In this theory, the gravitational field is coupled to a scalar field by a parity-violating term, which gives rise to characteristic signatures. Here we investigate how Chern-Simons gravity would affect the quasicircular inspiralling of a small, stellar-mass object into a large nonrotating supermassive black hole, and the accompanying emission of gravitational and scalar waves. We find the relevant equations describing the perturbation induced by the small object, and we solve them through the use of Green’s function techniques. Our results show that for a wide range of coupling parameters, the Chern-Simons coupling gives rise to an increase in total energy flux, which translates into a fewer number of gravitational-wave cycles over a certain bandwidth. For space-based gravitational-wave detectors such as LISA, this effect can be used to constrain the coupling parameter effectively.

  3. Adult Brtl/+ mouse model of osteogenesis imperfecta demonstrates anabolic response to sclerostin antibody treatment with increased bone mass and strength.

    Science.gov (United States)

    Sinder, B P; White, L E; Salemi, J D; Ominsky, M S; Caird, M S; Marini, J C; Kozloff, K M

    2014-08-01

    Treatments to reduce fracture rates in adults with osteogenesis imperfecta are limited. Sclerostin antibody, developed for treating osteoporosis, has not been explored in adults with OI. This study demonstrates that treatment of adult OI mice respond favorably to sclerostin antibody therapy despite retention of the OI-causing defect. Osteogenesis imperfecta (OI) is a heritable collagen-related bone dysplasia, characterized by brittle bones with increased fracture risk. Although OI fracture risk is greatest before puberty, adults with OI remain at risk of fracture. Antiresorptive bisphosphonates are commonly used to treat adult OI, but have shown mixed efficacy. New treatments which consistently improve bone mass throughout the skeleton may improve patient outcomes. Neutralizing antibodies to sclerostin (Scl-Ab) are a novel anabolic therapy that have shown efficacy in preclinical studies by stimulating bone formation via the canonical wnt signaling pathway. The purpose of this study was to evaluate Scl-Ab in an adult 6 month old Brtl/+ model of OI that harbors a typical heterozygous OI-causing Gly > Cys substitution on Col1a1. Six-month-old WT and Brtl/+ mice were treated with Scl-Ab (25 mg/kg, 2×/week) or Veh for 5 weeks. OCN and TRACP5b serum assays, dynamic histomorphometry, microCT and mechanical testing were performed. Adult Brtl/+ mice demonstrated a strong anabolic response to Scl-Ab with increased serum osteocalcin and bone formation rate. This anabolic response led to improved trabecular and cortical bone mass in the femur. Mechanical testing revealed Scl-Ab increased Brtl/+ femoral stiffness and strength. Scl-Ab was successfully anabolic in an adult Brtl/+ model of OI.

  4. Pharmacological inhibition of PPARγ increases osteoblastogenesis and bone mass in male C57BL/6 mice.

    Science.gov (United States)

    Duque, Gustavo; Li, Wei; Vidal, Christopher; Bermeo, Sandra; Rivas, Daniel; Henderson, Janet

    2013-03-01

    Infiltration of bone marrow with fat is a prevalent feature in people with age-related bone loss and osteoporosis, which correlates inversely with bone formation and positively with high expression levels of peroxisomal proliferator-activated receptor gamma (PPARγ). Inhibition of PPARγ thus represents a potential therapeutic approach for age-related bone loss. In this study, we examined the effect of PPARγ inhibition on bone in skeletally mature C57BL/6 male mice. Nine-month-old mice were treated with a PPARγ antagonist, bisphenol-A-diglycidyl ether (BADGE), alone or in combination with active vitamin D (1,25[OH](2) D(3) ) for 6 weeks. Micro-computed tomography and bone histomorphometry indicated that mice treated with either BADGE or BADGE + 1,25(OH)(2) D(3) had significantly increased bone volume and improved bone quality compared with vehicle-treated mice. This phenotype occurred in the absence of alterations in osteoclast number. Furthermore, the BADGE + 1,25(OH)(2) D(3) -treated mice exhibited higher levels of unmineralized osteoid. All of the treated groups showed a significant increase in circulating levels of bone formation markers without changes in bone resorption markers, while blood glucose, parathyroid hormone, and Ca(+) remained normal. Furthermore, treatment with BADGE induced higher levels of expression of vitamin D receptor within the bone marrow. Overall, treated mice showed higher levels of osteoblastogenesis and bone formation concomitant with decreased marrow adiposity and ex vivo adipogenesis. Taken together, these observations demonstrate that pharmacological inhibition of PPARγ may represent an effective anabolic therapy for osteoporosis in the near future.

  5. Factors associated with low bone mass in the hemodialysis patients – a cross-sectional correlation study

    Directory of Open Access Journals (Sweden)

    Huang Guey-Shiun

    2009-06-01

    Full Text Available Abstract Background Low bone mass is common in end-stage renal disease patients, especially those undergoing hemodialysis. It can lead to serious bone health problems such as fragility fractures. The purpose of this study is to investigate the risk factors of low bone mass in the hemodialysis patients. Methods Sixty-three subjects on hemodialysis for at least 6 months were recruited from a single center for this cross-sectional study. We collected data by questionnaire survey and medical records review. All subjects underwent a bone mineral density (BMD assay with dual-energy x-ray absorptiometry at the lumbar spine and right hip. Data were statistically analyzed by means of descriptive analysis, independent t test and one way analysis of variance for continuous variables, Pearson product-moment correlation to explore the correlated factors of BMD, and stepwise multiple linear regression to identify the predictors of low bone mass. Results Using WHO criteria as a cutoff point, fifty-one subjects (81% had a T-score lower than -1, of them 8 subjects (13% had osteoporosis with the femoral neck most commonly affected. Regarding risk factors, age, serum alkaline phosphatase (ALP level, and intact parathyroid hormone (iPTH level had significant negative correlations with the femoral neck and lumbar spine BMD. On the other hand, serum albumin level, effective exercise time, and body weight (BW had significant positive correlations with the femoral neck and lumbar spine BMD. Age, effective exercise time, and serum albumin level significantly predicted the femoral neck BMD (R2 × 0.25, whereas BW and the ALP level significantly predicted the lumbar spine BMD (R2 × 0.20. Conclusion This study showed that advanced age, low BW, low serum albumin level, and high ALP and iPTH levels were associated with a low bone mass in the hemodialysis patients. We suggest that regular monitoring of the femoral neck BMD, maintaining an adequate serum albumin level and BW

  6. Effects of repetitive loading on bone mass and geometry in young male tennis players: a quantitative study using MRI.

    Science.gov (United States)

    Ducher, Gaele; Daly, Robin M; Bass, Shona L

    2009-10-01

    Pre- and early puberty seem to be the most opportune times for exercise to improve bone strength in girls, but few studies have addressed this issue in boys. This study investigated the site-, surface-, and maturity-specific exercise-induced changes in bone mass and geometry in young boys. The osteogenic effects of loading were analyzed by comparing the playing and nonplaying humeri of 43 male pre-, peri-, and postpubertal competitive tennis players 10-19 yr of age. Total bone area, medullary area, and cortical area were determined at the mid (40-50%) and distal humerus (60-70%) of both arms using MRI. Humeral bone mass (BMC) was derived from a whole body DXA scan. In prepubertal boys, BMC was 17% greater in the playing compared with nonplaying arm (p < 0.001), which was accompanied by a 12-21% greater cortical area, because of greater periosteal expansion than medullary expansion at the midhumerus and periosteal expansion associated with medullary contraction at the distal humerus. Compared with prepuberty, the side-to-side differences in BMC (27%) and cortical area (20-33%) were greater in peripuberty (p < 0.01). No differences were found between peri- and postpuberty despite longer playing history in the postpubertal players. The osteogenic response to loading was greater in peri- compared with prepubertal boys, which is in contrast with our previous findings in girls and may be caused by differences in training history. This suggests that the window of opportunity to improve bone mass and size through exercise may be longer in boys than in girls.

  7. Software system for computing material and structural properties of bone and muscle in the lower extremity from pQCT

    Science.gov (United States)

    Makrogiannis, Sokratis; Ferrucci, Luigi

    2014-06-01

    Peripheral Quantitative Computed Tomography (pQCT) is a non-invasive imaging technology that is well-suited for quantification of bone structural and material properties. Because of its increasing use and applicability, the development of automated quantification methods for pQCT images is an appealing field of research. In this paper we introduce a software system for hard and soft tissue quantification in the lower leg using pQCT imaging data. The main stages of our approach are the segmentation and identification of bone, muscle and fat, and the computation of densitometric and geometric variables of each regional tissue type. Our system was validated against reference area and densitometric measurements over a set of test images and produced encouraging results.

  8. Estimated lean mass and fat mass differentially affect femoral bone density and strength index but are not FRAX independent risk factors for fracture.

    Science.gov (United States)

    Leslie, William D; Orwoll, Eric S; Nielson, Carrie M; Morin, Suzanne N; Majumdar, Sumit R; Johansson, Helena; Odén, Anders; McCloskey, Eugene V; Kanis, John A

    2014-11-01

    Although increasing body weight has been regarded as protective against osteoporosis and fractures, there is accumulating evidence that fat mass adversely affects skeletal health compared with lean mass. We examined skeletal health as a function of estimated total body lean and fat mass in 40,050 women and 3600 men age ≥50 years at the time of baseline dual-energy X-ray absorptiometry (DXA) testing from a clinical registry from Manitoba, Canada. Femoral neck bone mineral density (BMD), strength index (SI), cross-sectional area (CSA), and cross-sectional moment of inertia (CSMI) were derived from DXA. Multivariable models showed that increasing lean mass was associated with near-linear increases in femoral BMD, CSA, and CSMI in both women and men, whereas increasing fat mass showed a small initial increase in these measurements followed by a plateau. In contrast, femoral SI was relatively unaffected by increasing lean mass but was associated with a continuous linear decline with increasing fat mass, which should predict higher fracture risk. During mean 5-year follow-up, incident major osteoporosis fractures and hip fractures were observed in 2505 women and 180 men (626 and 45 hip fractures, respectively). After adjustment for fracture risk assessment tool (FRAX) scores (with or without BMD), we found no evidence that lean mass, fat mass, or femoral SI affected prediction of major osteoporosis fractures or hip fractures. Findings were similar in men and women, without significant interactions with sex or obesity. In conclusion, skeletal adaptation to increasing lean mass was positively associated with BMD but had no effect on femoral SI, whereas increasing fat mass had no effect on BMD but adversely affected femoral SI. Greater fat mass was not independently associated with a greater risk of fractures over 5-year follow-up. FRAX robustly predicts fractures and was not affected by variations in body composition.

  9. Testing Chern-Simons Modified Gravity with Gravitational-Wave Detections of Extreme-Mass-Ratio Binaries

    CERN Document Server

    Canizares, Priscilla; Sopuerta, Carlos F

    2012-01-01

    [abridged] The detection of gravitational waves from extreme-mass-ratio (EMRI) binaries, comprising a stellar-mass compact object orbiting around a massive black hole, is one of the main targets for low-frequency gravitational-wave detectors in space, like the Laser Interferometer Space Antenna (LISA or eLISA/NGO). The long-duration gravitational-waveforms emitted by such systems encode the structure of the strong field region of the massive black hole, in which the inspiral occurs. The detection and analysis of EMRIs will therefore allow us to study the geometry of massive black holes and determine whether their nature is as predicted by General Relativity and even to test whether General Relativity is the correct theory to describe the dynamics of these systems. To achieve this, EMRI modeling in alternative theories of gravity is required to describe the generation of gravitational waves. In this paper, we explore to what extent EMRI observations with LISA or eLISA/NGO might be able to distinguish between G...

  10. FIRST PRECISION LIGHT CURVE ANALYSIS OF THE NEGLECTED EXTREME MASS RATIO SOLAR-TYPE BINARY HR BOOTIS

    Energy Technology Data Exchange (ETDEWEB)

    Samec, Ronald G. [Faculty Research Associate, Pisgah Astronomical Research Institute, One Pari Drive, Rosman, NC 28772 (United States); Benkendorf, Barry; Dignan, James B. [Astronomy Group, Physics and Engineering Department, Bob Jones University, 1700 Wade Hampton Boulevard, Greenville, SC 29614 (United States); Robb, Russell [University of Victoria and Guest Observer, Dominion Astrophysical Observatory (Canada); Kring, James [Physics Department, Auburn University, 206 Allison Lab, Auburn, Alabama, 36849 (United States); Faulkner, Danny R. [University of South Carolina, Lancaster, 476 Hubbard Drive, Lancaster, SC 29720 (United States)

    2015-04-15

    HR Bootis is a neglected binary that is found to be a solar-type (G2V) extreme mass ratio binary (EMRB). It was discovered by Hanley and Shapley in 1940. Surprisingly, little has been published in the intervening years. In 1999 it was characterized by a 0.31587 day orbital period. Since that time it has been observed by various observers who have determined ∼20 timings of minimum light over the past ∼15,000 orbits. Our observations in 2012 represent the first precision curves in the BVR{sub c}I{sub c} Johnson–Cousins wavelength bands. The light curves have rather low amplitudes, averaging some 0.5 magnitudes, yet they exhibit total eclipses, which is typical of the rare group of solar-type EMRBs. An improved linear ephemeris was computed along with a quadratic ephemeris showing a decaying orbit, which indicates magnetic breaking may be occurring. The light curve solution reveals that HR Boo is a contact system with a somewhat low 21% Roche-lobe fill-out but a mass ratio of q = 4.09 (0.2444), which defines it as an EMRB. Two spots, both hot, were allowed to iterate to fit the light curve asymmetries. Their radii are 32° and 16°. Both are high-latitude polar spots indicative of strong magnetic activity. The shallow contact yet nearly equal component temperatures makes it an unusual addition to this group.

  11. Spectroscopy of the extreme-ultraviolet source Feige 24 - The binary orbit and the mass of the white dwarf

    Science.gov (United States)

    Thorstensen, J. R.; Charles, P. A.; Bowyer, S.; Margon, B.

    1978-01-01

    Results are reported for coude spectroscopy of the extreme-ultraviolet white dwarf Feige 24. Radial velocities of the H-alpha, He I 5876-A, and He I 6678-A emission lines, and the underlying M-dwarf absorption features, were determined from spectrograms obtained with the Lick 3-m telescope. The velocities show a binary period of 4.239(+ or - 0.0015) days. The emission-line and absorption-line velocities agree in phase, which indicates that the emission lines originate in the atmosphere of the M-dwarf secondary as a result of reprocessing of the EUV radiation. This effect is modeled, and the observed amplitude of the emission-line variability is used to place a lower limit on the orbital inclination. From these and other data it is shown that the mass of the white dwarf lies between 0.46 and 1.24 solar masses. Some possible implications for the evolution of binary stars are briefly discussed.

  12. Bone Mineral Density is an Independent Determinant of Left Ventricular Mass Index in the General Female Population

    OpenAIRE

    Lim, Young-Hyo; Shin, Jinho; Lee, Jae Ung; Lim, Heon Kil; Hong, Sangmo; Kim, Mi-Kyung; Choi, Bo Youl; Kim, Yu-Mi

    2010-01-01

    Background and Objectives Left ventricular hypertrophy (LVH) is a well known cardiovascular prognostic predictor. Osteoporosis has been suggested to be associated with cardiovascular disease. According to studies of primary hyperparathyroidism, a pathophysiological association between calcium metabolism and LVH has been suggested but is not yet fully understood. This study was performed to investigate the association between bone mineral density (BMD) and left ventricular mass index (LVMI) in...

  13. Infant dietary patterns and bone mass in childhood: the Generation R Study

    NARCIS (Netherlands)

    E.H. van den Hooven (Edith); D.H.M. Heppe (Denise); J.C. Kiefte-de Jong (Jessica); M.C. Medina-Gomez (Carolina); H.A. Moll (Henriëtte); A. Hofman (Albert); V.W.V. Jaddoe (Vincent); F. Rivadeneira Ramirez (Fernando); O.H. Franco (Oscar)

    2015-01-01

    textabstractConclusions: An infant dietary pattern characterized by high intakes of dairy and cheese, whole grains, and eggs is positively associated with bone development in childhood. Further research is needed to investigate the consequences for bone health in later life.Results: Higher adherence

  14. Determinants of bone mass and bone size in a large cohort of physically active young adult men

    Directory of Open Access Journals (Sweden)

    Garrett P

    2006-02-01

    Full Text Available Abstract The determinants of bone mineral density (BMD at multiple sites were examined in a fit college population. Subjects were 755 males (mean age = 18.7 years entering the United States Military Academy. A questionnaire assessed exercise frequency and milk, caffeine, and alcohol consumption and tobacco use. Academy staff measured height, weight, and fitness. Calcaneal BMD was measured by peripheral dual-energy x-ray absorptiometry (pDXA. Peripheral-quantitative computed tomography (pQCT was used to measure tibial mineral content, circumference and cortical thickness. Spine and hip BMD were measured by DXA in a subset (n = 159. Mean BMD at all sites was approximately one standard deviation above young normal (p

  15. DISCOVERY OF PULSATIONS, INCLUDING POSSIBLE PRESSURE MODES, IN TWO NEW EXTREMELY LOW MASS, He-CORE WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Hermes, J. J.; Montgomery, M. H.; Winget, D. E.; Bell, Keaton J.; Harrold, Samuel T. [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Gianninas, A.; Kilic, Mukremin, E-mail: jjhermes@astro.as.utexas.edu [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks Street, Norman, OK 73019 (United States)

    2013-03-10

    We report the discovery of the second and third pulsating extremely low mass (ELM) white dwarfs (WDs), SDSS J111215.82+111745.0 (hereafter J1112) and SDSS J151826.68+065813.2 (hereafter J1518). Both have masses < 0.25 M{sub Sun} and effective temperatures below 10, 000 K, establishing these putatively He-core WDs as a cooler class of pulsating hydrogen-atmosphere WDs (DAVs, or ZZ Ceti stars). The short-period pulsations evidenced in the light curve of J1112 may also represent the first observation of acoustic (p-mode) pulsations in any WD, which provide an exciting opportunity to probe this WD in a complimentary way compared to the long-period g-modes that are also present. J1112 is a T{sub eff} =9590 {+-} 140 K and log g =6.36 {+-} 0.06 WD. The star displays sinusoidal variability at five distinct periodicities between 1792 and 2855 s. In this star, we also see short-period variability, strongest at 134.3 s, well short of the expected g-modes for such a low-mass WD. The other new pulsating WD, J1518, is a T{sub eff} =9900 {+-} 140 K and log g =6.80 {+-} 0.05 WD. The light curve of J1518 is highly non-sinusoidal, with at least seven significant periods between 1335 and 3848 s. Consistent with the expectation that ELM WDs must be formed in binaries, these two new pulsating He-core WDs, in addition to the prototype SDSS J184037.78+642312.3, have close companions. However, the observed variability is inconsistent with tidally induced pulsations and is so far best explained by the same hydrogen partial-ionization driving mechanism at work in classic C/O-core ZZ Ceti stars.

  16. One year of abaloparatide, a selective peptide activator of the PTH1 receptor, increased bone mass and strength in ovariectomized rats.

    Science.gov (United States)

    Varela, Aurore; Chouinard, Luc; Lesage, Elisabeth; Guldberg, Robert; Smith, Susan Y; Kostenuik, Paul J; Hattersley, Gary

    2017-02-01

    Abaloparatide is a novel 34 amino acid peptide selected to be a potent and selective activator of the parathyroid hormone receptor 1 (PTHR1) signaling pathway. The effects of 12months of abaloparatide treatment on bone mass, bone strength and bone quality was assessed in osteopenic ovariectomized (OVX) rats. SD rats were subjected to OVX or sham surgery at 6months of age and left untreated for 3months to allow OVX-induced bone loss. Eighteen OVX rats were sacrificed after this bone depletion period, and the remaining OVX rats received daily s.c. injections of vehicle (n=18) or abaloparatide at 1, 5 or 25μg/kg/d (n=18/dose level) for 12months. Sham controls (n=18) received vehicle daily. Bone changes were assessed by DXA and pQCT after 0, 3, 6 or 12months of treatment, and destructive biomechanical testing was conducted at month 12 to assess bone strength and bone quality. Abaloparatide dose-dependently increased bone mass at the lumbar spine and at the proximal and diaphyseal regions of the tibia and femur. pQCT revealed that increased cortical bone volume at the tibia was a result of periosteal expansion and endocortical bone apposition. Abaloparatide dose-dependently increased structural strength of L4-L5 vertebral bodies, the femur diaphysis, and the femur neck. Increments in peak load for lumbar spine and the femur diaphysis of abaloparatide-treated rats persisted even after adjusting for treatment-related increments in BMC, and estimated material properties were maintained or increased at the femur diaphysis with abaloparatide. The abaloparatide groups also exhibited significant and positive correlations between bone mass and bone strength at these sites. These data indicate that gains in cortical and trabecular bone mass with abaloparatide are accompanied by and correlated with improvements in bone strength, resulting in maintenance or improvement in bone quality. Thus, this study demonstrated that long-term daily administration of abaloparatide to

  17. Physical activity and bone mineral accrual in boys with different body mass parameters during puberty: a longitudinal study.

    Directory of Open Access Journals (Sweden)

    Donvina Vaitkeviciute

    Full Text Available The aim of our longitudinal study was to investigate the relationships between physical activity and bone mass in boys with different body mass status during the years surrounding pubertal growth spurt. Two hundred and six boys entering puberty took part in this study. The subjects were divided into underweight (BMI 26.02 groups at baseline according to age related categories. Whole-body DXA scans were performed at baseline, after 12 and 24 months to assess body composition (lean body mass, fat mass, and total body (TB, lumbar spine (LS and femoral neck (FN bone mineral density (BMD parameters. Physical activity was measured by 7-day accelerometry. For longitudinal analysis, multilevel fixed effects regression models were constructed. Biological age, height and lean body mass had an effect for explanation of TB BMD, FN BMD and LS BMD. Moderate to vigorous physical activity (MVPA, vigorous physical activity (VPA and sedentary time (SED had the significant effect only on FN BMD. Being an underweight boy at the baseline indicated greater chance (p<0.01 to have lower TB BMD in the future (2 years at follow up development, compared to normal weight (estimates = -0.038, overweight (estimates = -0.061 and obese boys (estimates = -0.106.

  18. The Dynamic Response of Marine Life to Extreme Temperature and Low Oxygen Events Following the End-Permian Mass Extinction.

    Science.gov (United States)

    Pietsch, C.; Bottjer, D. J.

    2014-12-01

    The end-Permian mass extinction was the most devastating taxonomic and ecological crisis in the history of life on Earth. The recovery lasted 5 My making it the longest in geologic history, although the cause of the delay is still heavily debated. We find that additional environmental changes during the recovery interval reset the attempts that marine communities made toward ecological complexity, resulting in the overall appearance of a stagnant recovery. The extinction mechanisms during the end-Permian include extreme temperature change and low oxygen environments resulting from the volcanic emission of carbon dioxide and other toxic gasses to the atmosphere. The biotic response to ancient environmental change is a direct analog for the ecological impacts of modern anthropogenic climate change. We applied an ecological recovery rubric to benthic, sea floor dwelling, communities throughout the Early Triassic recovery in two major ocean basins. Newly collected bulk fossil data from the Moenkopi and Thaynes Formations from the Southwest US and the Werfen Formation in Italy were analyzed along with literature data. In Italy, directly following the extinction, low oxygen environments prevented an ecological rebound. Once low oxygen conditions receded, 600 kyr after the extinction, taxonomic diversity, fossil body size, and trace fossil complexity rebounded. A little more than 1 My into the Early Triassic, an extreme temperature event resulted in a reset of community complexity in both Italy and the Southwest US. The body size of gastropods and the repopulation of echinoderms were significantly inhibited as was trace fossil complexity. Low oxygen conditions that developed in the last ~2My of the Early Triassic limited diversity and body size in the Southwest United States. The stagnant recovery is re-interpreted as dynamic resets and rapid rebounds driven by environmental perturbations throughout the Early Triassic.

  19. Protective actions of soy isoflavones and n-3 PUFAs on bone mass in ovariectomized rats.

    Science.gov (United States)

    Watkins, Bruce A; Reinwald, Susan; Li, Yong; Seifert, Mark F

    2005-08-01

    Ovariectomy (OVX) in female rats precipitates a marked reduction in endogenous estrogen concentrations and induces bone remodeling abnormalities that augment bone loss and increase the risk of developing osteopenia. This research examined the combined effects of two levels of soy isoflavones (IFs), trace (-IF) and high (+IF) (0.03 and 3.43 mg/g protein, respectively), and two levels of n-3 polyunsaturated fatty acids (PUFAs) on bone conservation in 2-month-old sexually mature OVX Sprague-Dawley rats. All dietary treatments provided 110.4 g/kg of fat from either safflower oil (N6) or a blend of safflower oil and menhaden oil (N3). OVX rats were randomly assigned to the N6-IF, N6+IF, N3-IF and N3+IF groups. The OVX and sham rats were euthanized after 12 weeks of feeding. Data for sequential femoral and tibial in vivo bone mineral density and bone mineral content (BMC) measurements were determined every 4 weeks. The hindlimb mineral data indicated a trend toward a positive bone mineral-sparing effect related to +IF. Among the OVX rats, those fed the N3+IF diet had a significantly higher value for tibial BMC. The concentration of serum pyridinoline cross-links was significantly lower in the N3+IF group. These findings indicate a complementary action of soy IFs and n-3 PUFAs for attenuating bone mineral reduction in OVX rats.

  20. Antiosteoporotic effect of orally administered yolk-derived peptides on bone mass in women.

    Science.gov (United States)

    Abdou, Adham M; Watabe, Kazuya; Yamane, Tetsuro; Isono, Tadayuki; Okamura, Yoshitaka; Kawahito, Seiji; Takeshima, Kazuhito; Masuda, Kazuyuki; Kim, Mujo

    2014-05-01

    The main objective of this study was to verify the effect of oral intake of a yolk-derived peptide preparation (HYP) obtained by enzymatic hydrolysis of yolk water-soluble protein on bone markers and bone density in 65 perimenopausal women with an average age of 47.6 ± 5.2 years. Subjects were divided into three groups, and then enrolled in a 6-month, randomized, double-blind clinical trial. Bone formation and resorption markers were measured at 0, 3, and 6 months, while bone mineral density (BMD) in the lumbar spines was measured at 0 and 6 months. Although the bone formation marker levels showed the similarity changes among the groups, bone resorption markers in the test HYP group were significantly decreased after 3 and 6 months in comparison to other groups (P < 0.05). After 6 months, BMD in the test HYP group maintained at healthy numerical values whereas BMD values were decreased in other groups. Hence HYP would be an antiosteoporotic agent originated from natural food to maintain bone health, especially for women.

  1. No important influence of limited steroid exposure on bone mass during the first year after renal transplantation: a prospective, randomized, multicenter study.

    NARCIS (Netherlands)

    Meulen, C.G. ter; Riemsdijk, I.C. van; Hene, R.J.; Christiaans, M.H.; Borm, G.F.; Corstens, F.H.M.; Gelder, T. van; Hilbrands, L.B.; Weimar, W.; Hoitsma, A.J.

    2004-01-01

    BACKGROUND: Steroid-related bone loss is a recognized complication after renal transplantation. In a prospective, randomized, multicenter study we compared the influence of a steroid-free immunosuppressive regimen with a regimen with limited steroid exposure on the changes in bone mass after renal t

  2. Effects of probiotics, prebiotics, and synbiotics on mineral metabolism in ovariectomized rats — impact of bacterial mass, intestinal absorptive area and reduction of bone turn-over

    Directory of Open Access Journals (Sweden)

    Katharina E. Scholz-Ahrens

    2016-08-01

    Conclusion: SYN exerted a synergistic effect on bone mineralization, presumably due to changes in gut microbiota and ecology associated with large bowel digesta weight (most likely reflecting microbial mass and with large bowel weight (reflecting absorptive area, while bone turnover tended to be reduced as indicated by BAP.

  3. Polymorphisms of muscle genes are associated with bone mass and incident osteoporotic fractures in Caucasians

    DEFF Research Database (Denmark)

    Harsløf, Torben; Frost, M; Nielsen, T L

    2013-01-01

    The interaction between muscle and bone is complex. The aim of this study was to investigate if variations in the muscle genes myostatin (MSTN), its receptor (ACVR2B), myogenin (MYOG), and myoD1 (MYOD1) were associated with fracture risk, bone mineral density (BMD), bone mineral content (BMC......-29 years. Nine tag SNPs in the four genes were investigated. In the DOPS, individuals homozygous for the variant allele of the MSTN SNP rs7570532 had an increased risk of any osteoporotic fracture, with an HR of 1.82 (95 % CI 1.15-2.90, p = 0.01), and of nonvertebral osteoporotic fracture, with an HR of 2...... an association between a variant in MSTN and fracture risk and bone loss. Further studies are needed to confirm the findings....

  4. Assessment of genotoxic and cytotoxic hazards in brain and bone marrow cells of newborn rats exposed to extremely low-frequency magnetic field.

    Science.gov (United States)

    Rageh, Monira M; El-Gebaly, Reem H; El-Bialy, Nihal S

    2012-01-01

    The present study aimed to evaluate the association between whole body exposure to extremely low frequency magnetic field (ELF-MF) and genotoxic , cytotoxic hazards in brain and bone marrow cells of newborn rats. Newborn rats (10 days after delivery) were exposed continuously to 50 Hz, 0.5 mT for 30 days. The control group was treated as the exposed one with the sole difference that the rats were not exposed to magnetic field. Comet assay was used to quantify the level of DNA damage in isolated brain cells. Also bone marrow cells were flushed out to assess micronucleus induction and mitotic index. Spectrophotometric methods were used to measure the level of malondialdehyde (MDA) and the activity of glutathione (GSH) and superoxide dismutase (SOD). The results showed a significant increase in the mean tail moment indicating DNA damage in exposed group (P < 0.01, 0.001, 0.0001). Moreover ELF-MF exposure induced a significant (P < 0.01, 0.001) four folds increase in the induction of micronucleus and about three folds increase in mitotic index (P < 0.0001). Additionally newborn rats exposed to ELF-MF showed significant higher levels of MDA and SOD (P < 0.05). Meanwhile ELF-MF failed to alter the activity of GSH. In conclusion, the present study suggests an association between DNA damage and ELF-MF exposure in newborn rats.

  5. Assessment of Genotoxic and Cytotoxic Hazards in Brain and Bone Marrow Cells of Newborn Rats Exposed to Extremely Low-Frequency Magnetic Field

    Directory of Open Access Journals (Sweden)

    Monira M. Rageh

    2012-01-01

    Full Text Available The present study aimed to evaluate the association between whole body exposure to extremely low frequency magnetic field (ELF-MF and genotoxic , cytotoxic hazards in brain and bone marrow cells of newborn rats. Newborn rats (10 days after delivery were exposed continuously to 50 Hz, 0.5 mT for 30 days. The control group was treated as the exposed one with the sole difference that the rats were not exposed to magnetic field. Comet assay was used to quantify the level of DNA damage in isolated brain cells. Also bone marrow cells were flushed out to assess micronucleus induction and mitotic index. Spectrophotometric methods were used to measure the level of malondialdehyde (MDA and the activity of glutathione (GSH and superoxide dismutase (SOD. The results showed a significant increase in the mean tail moment indicating DNA damage in exposed group (P<0.01,0.001,0.0001. Moreover ELF-MF exposure induced a significant (P<0.01,0.001 four folds increase in the induction of micronucleus and about three folds increase in mitotic index (P<0.0001. Additionally newborn rats exposed to ELF-MF showed significant higher levels of MDA and SOD (P<0.05. Meanwhile ELF-MF failed to alter the activity of GSH. In conclusion, the present study suggests an association between DNA damage and ELF-MF exposure in newborn rats.

  6. The putative cannabinoid receptor GPR55 affects osteoclast function in vitro and bone mass in vivo

    OpenAIRE

    Whyte, Lauren S.; Ryberg, Erik; Sims, Natalie A.; Ridge, Susan A.; Mackie, Ken; Greasley, Peter J.; Ross, Ruth A.; Rogers, Michael J

    2009-01-01

    GPR55 is a G protein-coupled receptor recently shown to be activated by certain cannabinoids and by lysophosphatidylinositol (LPI). However, the physiological role of GPR55 remains unknown. Given the recent finding that the cannabinoid receptors CB1 and CB2 affect bone metabolism, we examined the role of GPR55 in bone biology. GPR55 was expressed in human and mouse osteoclasts and osteoblasts; expression was higher in human osteoclasts than in macrophage progenitors. Although the GPR55 agonis...

  7. Occupational Radiation Exposure to the Extremities of Medical Staff during Hysterosalpingography and Radionuclide Bone Scan Procedures in Several Nigerian Hospitals

    Directory of Open Access Journals (Sweden)

    Nnamdi Norbert Jibiri

    2016-10-01

    Full Text Available Objective: The practice of regular dose measurement helps to ascertain the level of occupational dose delivered to the staff involved in diagnostic procedures. This study was carried out to evaluate the dose exposed to the hands of radiologists and a radiologic technologist carrying out HSG and radionuclide bone scan examinations in several hospitals in Nigeria. Methods: Radiation doses exposed to the hands of radiologists and a technician carrying out hysterosalpingography (HSG and bone scan procedures were measured using calibrated thermo-luminescent dosimeters. Five radiologists and a radiologic technologist were included in the study for dose measurement. Results: The study indicates that each radiologist carried out approximately 2 examinations per week with the mean dose ranging between 0.49-0.62 mSv per week, resulting in an annual dose of 191 mSv. Similarly, the occupational dose delivered to both the left and right hands of a radiologic technologist administering 99mTc-methylene diphosphonate (MDP without cannula and with cannula were 10.68 (720.2 and 13.82 (556.4 mSv per week (and per annum, respectively. It was determined that the left hand of the personnel received higher doses than their right hand. Conclusion: The estimated annual dose during HSG is far below the annual dose limit for deterministic effects, however, it is greater than 10% of the applicable annual dose limit. Hence, routine monitoring is required to ensure adequate protection of the personnel. The total annual dose received during the bone scan exceeds the annual dose limit for both hands, and the dose to either left or right hand is greater than the dose limit of 500 mSv/yr. The radiologists monitored are not expected to incur any deterministic effects during HSG examinations, however, accumulated doses arising from the scattered radiation to the eyes, legs, and neck could be substantial and might lead to certain effects. More staff are required to administer 99m

  8. Renal Cell Carcinoma Metastasized to Pagetic Bone.

    Science.gov (United States)

    Ramirez, Ashley; Liu, Bo; Rop, Baiywo; Edison, Michelle; Valente, Michael; Burt, Jeremy

    2016-01-01

    Paget's disease of the bone, historically known as osteitis deformans, is an uncommon disease typically affecting individuals of European descent. Patients with Paget's disease of the bone are at increased risk for primary bone neoplasms, particularly osteosarcoma. Many cases of metastatic disease to pagetic bone have been reported. However, renal cell carcinoma metastasized to pagetic bone is extremely rare. A 94-year-old male presented to the emergency department complaining of abdominal pain. A computed tomography scan of the abdomen demonstrated a large mass in the right kidney compatible with renal cell carcinoma. The patient was also noted to have Paget's disease of the pelvic bones and sacrum. Within the pagetic bone of the sacrum, there was an enhancing mass compatible with renal cell carcinoma. A subsequent biopsy of the renal lesion confirmed renal cell carcinoma. Paget's disease of the bone places the patient at an increased risk for bone neoplasms. The most commonly reported sites for malignant transformation are the femur, pelvis, and humerus. In cases of malignant transformation, osteosarcoma is the most common diagnosis. Breast, lung, and prostate carcinomas are the most common to metastasize to pagetic bone. Renal cell carcinoma associated with Paget's disease of the bone is very rare, with only one prior reported case. Malignancy in Paget's disease of the bone is uncommon with metastatic disease to pagetic bone being extremely rare. We report a patient diagnosed with concomitant renal cell carcinoma and metastatic disease within Paget's disease of the sacrum. Further research is needed to assess the true incidence of renal cell carcinoma associated with pagetic bone.

  9. Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

    Institute of Scientific and Technical Information of China (English)

    Douglas J DiGirolamo; Vandana Singhal; Xiaoli Chang; Se-Jin Lee; Emily L Germain-Lee

    2015-01-01

    Osteogenesis imperfecta (OI) comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI, many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B (ACVR2B) in a mouse model of type III OI (oim). Treatment of 12-week-old oim mice with ACVR2B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy, wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.

  10. Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

    Science.gov (United States)

    DiGirolamo, Douglas J.; Singhal, Vandana; Chang, Xiaoli; Lee, Se-Jin; Germain-Lee, Emily L.

    2015-01-01

    Osteogenesis imperfecta (OI) comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI, many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B (ACVR2B) in a mouse model of type III OI (oim). Treatment of 12-week-old oim mice with ACVR2B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy, wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system. PMID:26161291

  11. Smoking and body fat mass in relation to bone mineral density and hip fracture: the Hordaland Health Study.

    Directory of Open Access Journals (Sweden)

    Jannike Øyen

    Full Text Available Lower bone mineral density (BMD in smokers may be attributable to lower body weight or fat mass, rather than to a direct effect of smoking. We analyzed the effects of smoking exposure, assessed by plasma cotinine, and body fat on BMD and the risk of subsequent hip fracture. In the community-based Hordaland Health Study (HUSK, 3003 participants 46-49 years and 2091 subjects 71-74 years were included. Cotinine was measured in plasma and information on health behaviors was obtained from self-administered questionnaires. BMD and total body soft tissue composition were measured by dual X-ray absorptiometry. Information on hip fracture was obtained from computerized records containing discharge diagnoses for hospitalizations between baseline examinations 1997-2000 through December 31st, 2009. In the whole cohort, moderate and heavy smokers had stronger positive associations between fat mass and BMD compared to never smokers (differences in regression coefficient (95% CI per % change in fat mass = 1.38 (0.24, 2.52 and 1.29 (0.17, 2.4, respectively. In moderate and heavy smokers there was a nonlinear association between BMD and fat mass with a stronger positive association at low compared to high levels of fat mass (Davies segmented test, p<0.001. In elderly women and men, heavy smokers had an increased risk of hip fracture compared to never smokers (hazard ratio = 3.31, 95% CI: 2.05, 5.35; p<0.001. In heavy smokers there was a tendency of a lower risk of hip fracture with higher percentage of fat mass. The deleterious effect of smoking on bone health is stronger in lean smokers than in smokers with high fat mass.

  12. Associations of Bone Mineral Density with Lean Mass, Fat Mass, and Dietary Patterns in Postmenopausal Chinese Women: A 2-Year Prospective Study.

    Directory of Open Access Journals (Sweden)

    Yongjie Chen

    Full Text Available To assess factors associated with bone mineral density (BMD in postmenopausal women in a longitudinal study, and to examine the relative contribution of lean mass, fat mass, dietary patterns, and years since menopause to BMD.Two hundred and eighty-two postmenopausal women were randomly selected from Hongqi Community Health Center, in Harbin City, China. All participants were followed up from 2009 to 2011. Dietary data were collected using a Food Frequency Questionnaire. BMD of the left hip, the lumbar spine, and the total body, and the body composition were measured by dual-energy X-ray absorptiometry at baseline and follow-up.Lean mass and fat mass were positively associated with BMD of the spine, hip, and the total body at both baseline and follow-up. The association between fat mass and BMD at the spine at baseline (P = 0.210 and at the spine (P = 0.116 and hip (P = 0.073 in the second year was not statistically significant when height was adjusted. Six dietary patterns were identified but only cereal grains-fruits pattern (P = 0.001 in the spine, P = 0.037 in hip and milk-root vegetables pattern (P = 0.010 in hip were associated with BMD of the spine and hip. The linear mixed model of follow-up data showed that lean mass, years since menopause, and age of menophania were the significant determinants of BMD of all sites. Moreover, lean mass was the best determinant of BMD (VIP = 1.936.Lean mass, years since menopause, age of menophania and dietary patterns are the important determinants of BMD of the spine, hip, and the total body. Lean mass is the best determinant of BMD.

  13. The impact of realistic models of mass segregation on the event rate of extreme-mass ratio inspirals and cusp re-growth

    CERN Document Server

    Amaro-Seoane, Pau

    2010-01-01

    One of the most interesting sources of gravitational waves (GWs) for LISA is the inspiral of compact objects on to a massive black hole (MBH), commonly referred to as an "extreme-mass ratio inspiral" (EMRI). The small object, typically a stellar black hole (bh), emits significant amounts of GW along each orbit in the detector bandwidth. The slowly, adiabatic inspiral of these sources will allow us to map space-time around MBHs in detail, as well as to test our current conception of gravitation in the strong regime. The event rate of this kind of source has been addressed many times in the literature and the numbers reported fluctuate by orders of magnitude. On the other hand, recent observations of the Galactic center revealed a dearth of giant stars inside the inner parsec relative to the numbers theoretically expected for a fully relaxed stellar cusp. The possibility of unrelaxed nuclei (or, equivalently, with no or only a very shallow cusp) adds substantial uncertainty to the estimates. Having this timely ...

  14. Physical education in West Virginia schools: are we doing enough to generate peak bone mass and promote skeletal health?

    Science.gov (United States)

    Shuler, Franklin D; Lycans, Dana; Gill, Thomas; Oliashirazi, Ali

    2013-01-01

    Peak bone mass (PBM) is attained at 25-35 years of age, followed by a lifelong decline in bone strength. The most rapid increase in bone mass occurs between the ages of 12-17. Daily school physical education (PE) programs have been shown to produce measurable increases in PBM, but are not federally mandated. Increases in PBM can decrease the lifelong risk of osteoporosis and fractures; critical for West Virginia prevention programs. Nationally only 1 in 6 schools require PE three days per week, with 4% of elementary schools, 8% of middle schools and 2% of high schools providing daily PE. In 2005, West Virginia passed the Healthy Lifestyles Act that returned physical education to the K-12 curriculum. This law requires only one credit of PE from grades 9-12 and provides only 35% of the recommended PE for grades K-12. This article highlights the relationship of PE to PBM and discusses the potential impact on West Virginia skeletal health.

  15. A nonlinear scalar model of extreme mass ratio inspirals in effective field theory I. Self force through third order

    CERN Document Server

    Galley, Chad R

    2010-01-01

    The motion of a small compact object in a background spacetime is investigated in the context of a model nonlinear scalar field theory. This model is constructed to have a perturbative structure analogous to the General Relativistic description of extreme mass ratio inspirals (EMRIs). We apply the effective field theory approach to this model and calculate the finite part of the self force on the small compact object through third order in the ratio of the size of the compact object to the curvature scale of the background (e.g., black hole) spacetime. We use well-known renormalization methods and demonstrate the consistency of the formalism in rendering the self force finite at higher orders within a point particle prescription for the small compact object. This nonlinear scalar model should be useful for studying various aspects of higher-order self force effects in EMRIs but within a comparatively simpler context than the full gravitational case. These aspects include developing practical schemes for highe...

  16. The Relationship of Age, Body Mass Index, and Individual Habit to Bone Mineral Density in Adults

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soung Ock; Lee, In Ja; Shin, Gwi Soon [Dept. of Radiologic Techology, Dongnam Health College, Suwon (Korea, Republic of)

    2008-12-15

    We studied the change of bone mineral density (BMD) by age, body mass index (BMI), coffee, carbonated drink, alcohol, smoking, and exercise in adults who checked in health center. The number of study subjects was total 268 persons (women of 136 persons and men of 132 persons). The BMD was determined in lumbar spine and femoral neck by dual energy x-ray absorptiometry. And we got some results as below : 1. In women, mean body height was , mean body weight was 155.8{+-}6.0 cm, and mean BMI was 56.8{+-}7.9 kg. In men, mean body height was 169.1{+-}6.0 cm, mean body weight was 69.0{+-}9.5 kg, and mean BMI was 24.1{+-}2.7 kg/m{sup 2}. 2. BMD decreased as age increased, and the age was the most determinant factor for BMD (p<0.01). Women's BMD decreased rapidly in the groups aged {>=}50s, while men's BMD decreased gradually with age. In addition, for both sex, lower BMD was measured in lumbar spine than in femoral neck. 3. BMD increased in high BMI, and BMD with BMI increased distinctly in the group aged 50s. But their relationship was not significant. 4. In view of the distribution by three BMD categories, women's BMD was mostly normal in the groups aged {>=}40s but the rate of osteopenia and osteoporosis was similar in the group aged 50s, and the rate of osteoporosis was the highest in the groups aged 60s and 70s. Men's BMD was mostly normal through all groups except the group aged 70s. 5. Coffee and carbonated drink were not influenced in BMD. But alcohol-drinking group showed higher BMD than non-drinking group, and alcohol was statistically significant determinant for BMD (p<0.05). Smoking and exercise were not statistically significant determinant of BMD.

  17. The Preventive Effect of Calcium Supplementation on Weak Bones Caused by the Interaction of Exercise and Food Restriction in Young Female Rats During the Period from Acquiring Bone Mass to Maintaining Bone Mass

    OpenAIRE

    Aikawa, Yuki; Agata, Umon; Kakutani, Yuya; Kato, Shoyo; Noma, Yuichi; Hattori, Satoshi; Ogata, Hitomi; Ezawa, Ikuko; Omi, Naomi

    2016-01-01

    Increasing calcium (Ca) intake is important for female athletes with a risk of weak bone caused by inadequate food intake. The aim of the present study was to examine the preventive effect of Ca supplementation on low bone strength in young female athletes with inadequate food intake, using the rats as an experimental model. Seven-week-old female Sprague-Dawley rats were divided into four groups: the sedentary and ad libitum feeding group (SED), voluntary running exercise and ad libitum feedi...

  18. Monitoring of alendronate treatment and prediction of effect on bone mass by biochemical markers in the early postmenopausal intervention cohort study

    DEFF Research Database (Denmark)

    Ravn, Pernille; Hosking, D; Thompson, D;

    1999-01-01

    To establish whether biochemical markers could be used to monitor alendronate (ALN) treatment and predict long-term response in bone mass, we used results from an ongoing, randomized trial of ALN treatment for prevention of postmenopausal osteoporosis (n = 1202). In women treated with ALN (5 mg......-point, validly identified women who responded, on ALN treatment, with a stabilization or an increase in bone mass. However, lack of decrease below the cut-point in NTX or OC could not be used to identify women with a bone loss during ALN treatment....

  19. 牵拉成骨技术治疗下肢大段骨缺损%Distraction osteogenesis for large bone defect of the lower extremity

    Institute of Scientific and Technical Information of China (English)

    王富明; 陈鸿奋; 陈滨; 任高宏; 杨运平; 秦煜; 王钢

    2011-01-01

    Objective To discuss the therapeutic effect of distraction osteogenesis for large bone defect of the lower extremity. Methods From August 2002 to August 2010, 11 patients with large bone defect at the lower extremity were treated with distraction osteogenesis. They were 10 men and one woman, aged from 14 to 53 years (average, 34. S years). The defect was at the right tibia in 7 cases, left tibia in 3 cases and right femur in one case. The lengths of bone defect ranged from 5 to 15 cm (average, 8. 6 cm). Results The patients were followed up for 7 to 48 months, with a mean period of 27. 3 months. The treatment of 9 cases was over, with a mean healing index of 1. 99 months/cm. According to the Paley evaluation system, the bony results were excellent in 6 and good in 3 patients; the functional results were excellent in 4, good in 4, and fair in one patient. Two cases were still in the mineralization period. Conclusion Treatment of large bone defects with distraction osteogenesis is simple and can obtain satisfactory therapeutic effects, especially when a monolateral external fixator is used for the simple shaft bone defect.%目的 探讨应用牵拉成骨技术治疗下肢大段骨缺损的临床疗效.方法 回顾性分析2002年8月至2010年8月收治的11例下肢大段骨缺损患者临床资料,男10例,女1例;年龄14~53岁,平均34.5岁.均行牵拉成骨治疗,右侧胫骨7例,左侧胫骨3例,右侧股骨1例;骨缺损长度5~15cm,平均8.6 cm;9例治疗已结束,2例仍处于矿化阶段.结果 所有患者术后获7~48个月(平均27.3个月)随访.9例治疗结束患者,平均骨愈合指数为1.99个月/cm;根据Paley评价系统评价骨性结果:优6例,良3例,优良率为100%;功能结果:优4例,良4例,一般1例.结论应用牵拉成骨技术治疗大段骨缺损,手术操作简单,尤其是对于单纯骨干缺损患者,采用单边外固定支架治疗,且其手术操作更为简洁.

  20. Palmitoyl acyltransferase, Zdhhc13, facilitates bone mass acquisition by regulating postnatal epiphyseal development and endochondral ossification: a mouse model.

    Directory of Open Access Journals (Sweden)

    I-Wen Song

    Full Text Available ZDHHC13 is a member of DHHC-containing palmitoyl acyltransferases (PATs family of enzymes. It functions by post-translationally adding 16-carbon palmitate to proteins through a thioester linkage. We have previously shown that mice carrying a recessive Zdhhc13 nonsense mutation causing a Zdhcc13 deficiency develop alopecia, amyloidosis and osteoporosis. Our goal was to investigate the pathogenic mechanism of osteoporosis in the context of this mutation in mice. Body size, skeletal structure and trabecular bone were similar in Zdhhc13 WT and mutant mice at birth. Growth retardation and delayed secondary ossification center formation were first observed at day 10 and at 4 weeks of age, disorganization in growth plate structure and osteoporosis became evident in mutant mice. Serial microCT from 4-20 week-olds revealed that Zdhhc13 mutant mice had reduced bone mineral density. Through co-immunoprecipitation and acyl-biotin exchange, MT1-MMP was identified as a direct substrate of ZDHHC13. In cells, reduction of MT1-MMP palmitoylation affected its subcellular distribution and was associated with decreased VEGF and osteocalcin expression in chondrocytes and osteoblasts. In Zdhhc13 mutant mice epiphysis where MT1-MMP was under palmitoylated, VEGF in hypertrophic chondrocytes and osteocalcin at the cartilage-bone interface were reduced based on immunohistochemical analyses. Our results suggest that Zdhhc13 is a novel regulator of postnatal skeletal development and bone mass acquisition. To our knowledge, these are the first data to suggest that ZDHHC13-mediated MT1-MMP palmitoylation is a key modulator of bone homeostasis. These data may provide novel insights into the role of palmitoylation in the pathogenesis of human osteoporosis.

  1. Palmitoyl acyltransferase, Zdhhc13, facilitates bone mass acquisition by regulating postnatal epiphyseal development and endochondral ossification: a mouse model.

    Science.gov (United States)

    Song, I-Wen; Li, Wei-Ru; Chen, Li-Ying; Shen, Li-Fen; Liu, Kai-Ming; Yen, Jeffrey J Y; Chen, Yi-Ju; Chen, Yu-Ju; Kraus, Virginia Byers; Wu, Jer-Yuarn; Lee, M T Michael; Chen, Yuan-Tsong

    2014-01-01

    ZDHHC13 is a member of DHHC-containing palmitoyl acyltransferases (PATs) family of enzymes. It functions by post-translationally adding 16-carbon palmitate to proteins through a thioester linkage. We have previously shown that mice carrying a recessive Zdhhc13 nonsense mutation causing a Zdhcc13 deficiency develop alopecia, amyloidosis and osteoporosis. Our goal was to investigate the pathogenic mechanism of osteoporosis in the context of this mutation in mice. Body size, skeletal structure and trabecular bone were similar in Zdhhc13 WT and mutant mice at birth. Growth retardation and delayed secondary ossification center formation were first observed at day 10 and at 4 weeks of age, disorganization in growth plate structure and osteoporosis became evident in mutant mice. Serial microCT from 4-20 week-olds revealed that Zdhhc13 mutant mice had reduced bone mineral density. Through co-immunoprecipitation and acyl-biotin exchange, MT1-MMP was identified as a direct substrate of ZDHHC13. In cells, reduction of MT1-MMP palmitoylation affected its subcellular distribution and was associated with decreased VEGF and osteocalcin expression in chondrocytes and osteoblasts. In Zdhhc13 mutant mice epiphysis where MT1-MMP was under palmitoylated, VEGF in hypertrophic chondrocytes and osteocalcin at the cartilage-bone interface were reduced based on immunohistochemical analyses. Our results suggest that Zdhhc13 is a novel regulator of postnatal skeletal development and bone mass acquisition. To our knowledge, these are the first data to suggest that ZDHHC13-mediated MT1-MMP palmitoylation is a key modulator of bone homeostasis. These data may provide novel insights into the role of palmitoylation in the pathogenesis of human osteoporosis.

  2. High Insulin Levels in KK-Ay Diabetic Mice Cause Increased Cortical Bone Mass and Impaired Trabecular Micro-Structure

    Directory of Open Access Journals (Sweden)

    Cen Fu

    2015-04-01

    Full Text Available Type 2 diabetes mellitus (T2DM is a chronic disease characterized by hyperglycemia, hyperinsulinemia and complications, including obesity and osteoporosis. Rodents have been widely used to model human T2DM and investigate its effect on the skeleton. We aimed to investigate skeletal alterations in Yellow Kuo Kondo (KK-Ay diabetic mice displaying high insulin and glucose levels. Bone mineral density (BMD, micro-architecture and bone metabolism-related genes were analyzed. The total femoral areal BMD (aBMD, cortical volumetric BMD (vBMD and thickness were significantly increased in KK-Ay mice, while the trabecular vBMD and mineralized bone volume/tissue volume (BV/TV, trabecular thickness and number were decreased compared to C57BL mice. The expression of both osteoblast-related genes, such as osteocalcin (OC, bone sialoprotein, Type I Collagen, osteonectin, RUNX2 and OSX, and osteoclast-related genes, such as TRAP and TCIRG, were up-regulated in KK-Ay mice. Correlation analyses showed that serum insulin levels were positively associated with aBMD, cortical vBMD and thickness and negatively associated with trabecular vBMD and micro-architecture. In addition, serum insulin levels were positively related to osteoblast-related and osteoclast-related gene expression. Our data suggest that high insulin levels in KK-Ay diabetic mice may increase cortical bone mass and impair trabecular micro-structure by up-regulating osteoblast-and osteoclast-related gene expression.

  3. Acupuncture Increases Bone Strength by Improving Mass and Structure in Established Osteoporosis after Ovariectomy in Rats

    Institute of Scientific and Technical Information of China (English)

    WenPing Zhang; Masayuki Kanehara; YanJun Zhang; ZhiFeng Yu; GuoXia Zhang; YouXin Yang; Saori Tachi; Torao Ishida

    2006-01-01

    The effects of acupuncture on bone biomechanical properties and histomorphometry in ovariectomized (OVX) rats were studied. Twenty-four 8-week-old female Sprague-Dawley rats were randomly assigned to three groups: sham, model and acupuncture. Rats in the model and acupuncture groups were ovariectomized,while those in the sham group underwent a sham operation. All rats were anesthetized and fastened for 15minutes, and for the acupuncture group, needling on Pishu (BL20) and Shenshu (BL23) was performed.Blood and urine were collected to measure serum osteocalcin (OC) and urinary calcium, phosphorus or deoxypyridinoline (Dpd). After 16 weeks of treatment, all the rats were killed and their tibiae and femora were removed. The tibiae were used for analyses of bone histomorphometry and the femora for a three-point bending test. Acupuncture gave significant protection against ovariectomy-caused decline on femoral strength in the mechanical test, increased the trabecular bone volume and thickness, lowered the trabecular separation of tibiae and restricted the excretion of phosphorus and Dpd, while promoting the concentrations of serum osteocalcin as compared with model rats. These results seemed to indicate that acupuncture on the points of Pishu (BL20) and Shenshu (BL23) not only promoted the bone formation but also suppressed the bone resorption induced by OVX in osteoporotic rats, which suggests that it would be a potentially useful and convenient method in preventing osteoporosis.

  4. Selective Determinants of Low Bone Mineral Mass in Adult Women with Anorexia Nervosa

    Directory of Open Access Journals (Sweden)

    Andrea Trombetti

    2013-01-01

    Full Text Available We investigated the relative effect of amenorrhea and insulin-like growth factor-I (sIGF-I levels on cancellous and cortical bone density and size. We investigated 66 adult women with anorexia nervosa. Lumbar spine and proximal femur bone mineral density was measured by DXA. We calculated bone mineral apparent density. Structural geometry of the spine and the hip was determined from DXA images. Weight and BMI, but not height, as well as bone mineral content and density, but not area and geometry parameters, were lower in patients with anorexia nervosa as compared with the control group. Amenorrhea, disease duration, and sIGF-I were significantly associated with lumbar spine and proximal femur BMD. In a multiple regression model, we found that sIGF-I was the only significant independent predictor of proximal femur BMD, while duration of amenorrhea was the only factor associated with lumbar spine BMD. Finally, femoral neck bone mineral apparent density, but not hip geometry variables, was correlated with sIGF-I. In anorexia nervosa, spine BMD was related to hypogonadism, whereas sIGF-I predicted proximal femur BMD. The site-specific effect of sIGF-I could be related to reduced volumetric BMD rather than to modified hip geometry.

  5. Decreased peak bone mass is associated with a 3-bp deletion/insertion of the CYP19 intron 4 polymorphism: preliminary data from the GOOS study.

    Science.gov (United States)

    Kastelan, D; Grubic, Z; Kraljevic, I; Duric, K; Kardum, I; Dusek, T; Stingl, K; Giljevic, Z; Kerhin-Brkljacic, V; Suchanek, E; Korsic, M

    2007-06-01

    Finding that estrogen plays an important role in bone homeostasis in men prompted research on relationship of polymorphism at the CYP19 gene and the bone mass. Therefore, influence of 3-bp deletion/insertion polymorphism of CYP19 (TTTA)7 allele on the peak bone mass attainment in males was studied. Fifty-eight unrelated male participants, aged 21-35, were selected depending on the presence of (TTTA)7 (no.=19) or (TTTA)7-3 (no.=39) alleles from the initial cohort of 92 young males. Heterozygotes (TTTA)7/(TTTA)7-3 (no.=13) were not included in the analysis. Serum levels of estradiol, free testosterone, 25-hydroxyvitamin D, bone alkaline phosphatase, osteocalcin, and beta-crosslaps were measured. Bone mass was measured by DXA at the hip and at the spine. (TTTA)7-3 allele was associated with significantly lower femoral neck bone mineral density (BMD) (p=0.02). Logistic regression model indicated strong association of (TTTA)7-3 allele with low BMD in the range of osteopenia/osteoporosis (p=0.014, odds ratio 12.36, confidence intervals 1.65-92.46). In the present study association of 3-bp deletion polymorphism of the (TTTA)7 allele with decreased peak bone mass in males is reported for the first time. However, further studies are necessary to elucidate the functional relevance of this polymorphism.

  6. Prenatal calcium and vitamin D intake, and bone mass in later life.

    Science.gov (United States)

    Curtis, Elizabeth M; Moon, Rebecca J; Dennison, Elaine M; Harvey, Nicholas C

    2014-06-01

    The aging population will result in an increasing burden of osteoporotic fractures, necessitating the identification of novel strategies for prevention. There is increasing recognition that factors in utero may influence bone mineral accrual, and, thus, osteoporosis risk. The role of calcium and vitamin D has received much attention in recent years, and in this review, we will survey available studies relating maternal calcium and vitamin D status during pregnancy to offspring bone development. The evidence base supporting a positive influence on intrauterine skeletal growth appears somewhat stronger for maternal 25(OH)-vitamin D concentration than for calcium intake, and the available data point toward the need for high-quality randomized controlled trials in order to inform public health policy. It is only with such a rigorous approach that it will be possible to delineate the optimal strategy for vitamin D supplementation in pregnancy in relation to offspring bone health.

  7. Sequential treatment with basic fibroblast growth factor and PTH is more efficacious than treatment with PTH alone for increasing vertebral bone mass and strength in osteopenic ovariectomized rats

    DEFF Research Database (Denmark)

    Iwaniec, U.T.; Mosekilde, Li.; Mitova-Caneva, N.G.

    2002-01-01

    The study was designed 1) to determine whether treatment with basic fibroblast growth factor (bFGF) and PTH is more efficacious than treatment with PTH alone for increasing bone mass and strength and improving trabecular microarchitecture in osteopenic ovariectomized rats, and 2) to assess whether...... prior and concurrent administration of the antiresorptive agents estrogen and risedronate suppresses the bone anabolic response to treatment with bFGF alone and sequential treatment with bFGF and PTH. Three-month-old female Sprague Dawley rats were ovariectomized (OVX) or sham-operated (sham...... of OVX rats with PTH alone increased vertebral cancellous bone mass and strength to the level of vehicle-treated sham rats. Sequential treatment of OVX rats with bFGF and PTH further augmented vertebral bone mass and strength to a level above that observed in OVX rats treated with PTH alone...

  8. Elastic recoil detection (ERD) with extremely heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Forster, J.S. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Currie, P.J. [Royal Tyrrell Museum, Drumheller, Alberta T0J 0Y0 (Canada); Davies, J.A. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Siegele, R. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Wallace, S.G. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Zelenitsky, D. [Department of Geology and Geophysics, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)

    1996-06-01

    Extremely heavy-ion beams such as {sup 209}Bi in elastic recoil detection (ERD) make ERD a uniquely valuable technique for thin-film analysis of elements with mass {<=}100. We report ERD measurements of compositional analysis of dinosaur eggshells and bones. We also show the capability of the ERD technique on studies of thin-film, high-temperature superconductors. (orig.).

  9. Testing Chern-Simons modified gravity with gravitational-wave detections of extreme-mass-ratio binaries

    Science.gov (United States)

    Canizares, Priscilla; Gair, Jonathan R.; Sopuerta, Carlos F.

    2012-08-01

    The detection of gravitational waves from extreme-mass-ratio inspirals (EMRI) binaries, comprising a stellar-mass compact object orbiting around a massive black hole, is one of the main targets for low-frequency gravitational-wave detectors in space, like the Laser Interferometer Space Antenna (LISA) or evolved LISA/New Gravitational Observatory (eLISA/NGO). The long-duration gravitational-waveforms emitted by such systems encode the structure of the strong field region of the massive black hole, in which the inspiral occurs. The detection and analysis of EMRIs will therefore allow us to study the geometry of massive black holes and determine whether their nature is as predicted by general relativity and even to test whether general relativity is the correct theory to describe the dynamics of these systems. To achieve this, EMRI modeling in alternative theories of gravity is required to describe the generation of gravitational waves. However, up to now, only a restricted class of theories has been investigated. In this paper, we explore to what extent EMRI observations with a space-based gravitational-wave observatory like LISA or eLISA/NGO might be able to distinguish between general relativity and a particular modification of it, known as dynamical Chern-Simons modified gravity. Our analysis is based on a parameter estimation study which uses approximate gravitational waveforms obtained via a radiative-adiabatic method. In this framework, the trajectory of the stellar object is modeled as a sequence of geodesics in the spacetime of the modified-gravity massive black hole. The evolution between geodesics is determined by flux formulae based on general relativistic post-Newtonian and black hole perturbation theory computations. Once the trajectory of the stellar compact object has been obtained, the waveforms are computed using the standard multipole formulae for gravitational radiation applied to this trajectory. Our analysis is restricted to a five

  10. New insights into PM2.5 chemical composition and sources in two major cities in China during extreme haze events using aerosol mass spectrometry

    Science.gov (United States)

    Elser, Miriam; Huang, Ru-Jin; Wolf, Robert; Slowik, Jay G.; Wang, Qiyuan; Canonaco, Francesco; Li, Guohui; Bozzetti, Carlo; Daellenbach, Kaspar R.; Huang, Yu; Zhang, Renjian; Li, Zhengqiang; Cao, Junji; Baltensperger, Urs; El-Haddad, Imad; Prévôt, André S. H.

    2016-03-01

    During winter 2013-2014 aerosol mass spectrometer (AMS) measurements were conducted for the first time with a novel PM2.5 (particulate matter with aerodynamic diameter ≤ 2.5 µm) lens in two major cities of China: Xi'an and Beijing. We denote the periods with visibility below 2 km as extreme haze and refer to the rest as reference periods. During the measurements in Xi'an an extreme haze covered the city for about a week and the total non-refractory (NR)-PM2.5 mass fraction reached peak concentrations of over 1000 µg m-3. During the measurements in Beijing two extreme haze events occurred, but the temporal extent and the total concentrations reached during these events were lower than in Xi'an. Average PM2.5 concentrations of 537 ± 146 and 243 ± 47 µg m-3 (including NR species and equivalent black carbon, eBC) were recorded during the extreme haze events in Xi'an and Beijing, respectively. During the reference periods the measured average concentrations were 140 ± 99 µg m-3 in Xi'an and 75 ± 61 µg m-3 in Beijing. The relative composition of the NR-PM2.5 evolved substantially during the extreme haze periods, with increased contributions of the inorganic components (mostly sulfate and nitrate). Our results suggest that the high relative humidity present during the extreme haze events had a strong effect on the increase of sulfate mass (via aqueous phase oxidation of sulfur dioxide). Another relevant characteristic of the extreme haze is the size of the measured particles. During the extreme haze events, the AMS showed much larger particles, with a volume weighted mode at about 800 to 1000 nm, in contrast to about 400 nm during reference periods. These large particle sizes made the use of the PM2.5 inlet crucial, especially during the severe haze events, where 39 ± 5 % of the mass would have been lost in the conventional PM1 (particulate matter with aerodynamic diameter ≤ 1 µm) inlet. A novel positive matrix factorization procedure was developed to

  11. New insights into PM2.5 chemical composition and sources in two major cities in China during extreme haze events using aerosol mass spectrometry

    Directory of Open Access Journals (Sweden)

    M. Elser

    2015-11-01

    Full Text Available During winter 2013–2014 aerosol mass spectrometer (AMS measurements were conducted for the first time with a novel PM2.5 (particulate matter with aerodynamic diameter ≤ 2.5 μm lens in two major cities of China: Xi'an and Beijing. We denote the periods with visibility below 2 km as extreme haze and refer to the rest as reference periods. During the measurements in Xi'an an extreme haze covered the city for about a week and the total non-refractory (NR-PM2.5 mass fraction reached peak concentrations of over 1000 μg m-3. During the measurements in Beijing two extreme haze events occurred, but the temporal extent and the total concentrations reached during these events were lower than in Xi'an. Average PM2.5 concentrations of 537 ± 146 μg m-3 and 243 ± 47 μg m-3 (including NR species and equivalent black carbon, eBC were recorded during the extreme haze events in Xi'an and Beijing, respectively. During the reference periods the measured average concentrations were 140 ± 99 μg m-3 in Xi'an and 75 ± 61 μg m-3 in Beijing. The relative composition of the NR-PM2.5 evolved substantially during the extreme haze periods, with increased contributions of the inorganic components (mostly sulfate and nitrate. Our results suggest that the high relative humidity present during the extreme haze events had a strong effect on the increase of sulfate mass (via aqueous phase oxidation of sulfur dioxide. Another relevant characteristic of the extreme haze is the size of the measured particles. During the extreme haze events, the AMS showed much larger particles, with a volume weighted mode at about 800 to 1000 nm, in contrast to about 400 nm during reference periods. These large particle sizes made the use of the PM2.5 inlet crucial, especially during the severe haze events, where 39 ± 5 % of the mass would have been lost in the conventional PM1 (particulate matter with aerodynamic diameter ≤ 1 μm inlet. A novel positive matrix factorization procedure

  12. Bone mass and vitamin D levels in Parkinson's disease: is there any difference between genders?

    Science.gov (United States)

    Ozturk, Erhan Arif; Gundogdu, Ibrahim; Tonuk, Burak; Kocer, Bilge Gonenli; Tombak, Yasemin; Comoglu, Selcuk; Cakci, Aytul

    2016-08-01

    [Purpose] The aim of this study was to determine the bone mineral density, vitamin D level, and frequencies of osteopenia and osteoporosis in patients with Parkinson's disease and to compare male and female patients with the controls separately. [Subjects and Methods] One hundred fifteen Parkinson's disease patients (47 males, 68 females; age range: 55-85 years) and 117 age- and gender-matched controls (47 males, 70 females) were enrolled in the study. Bone mineral density measured by dual-energy X-ray absorptiometry and serum D vitamin levels of each participant were recorded. [Results] The mean lumbar spine, femur neck, and total femur bone mineral density levels, T-scores, and vitamin D levels were found to be significantly lower in Parkinson's disease patients in both genders. Furthermore, osteoporosis rates were found be significantly higher only in female Parkinson's disease patients compared with female controls. [Conclusion] Data from the present study revealed that while osteoporosis was significantly higher only in female Parkinson's disease patients, all Parkinson's disease patients had lower bone mineral density scores and vitamin D levels compared with the controls regardless of gender, suggesting that clinicians should pay attention to the osteoporosis risk in Parkinson's disease and that adequate preventive measures should be taken in order to limit the future risk due to osteoporotic fractures.

  13. Calcium and vitamin D requirements for optimal bone mass during adolescence

    Science.gov (United States)

    There remains very strong interest in the calcium and vitamin D requirements of adolescents related to bone health. The Institute of Medicine (IOM) released new dietary guidelines in late 2010 for these nutrients. These guidelines were primarily based on literature published in 2009 and earlier and ...

  14. Growth hormone mitigates loss of periosteal bone formation and muscle mass in disuse osteopenic rats

    DEFF Research Database (Denmark)

    Grubbe, M.-C.; Thomsen, J. S.; Nyengaard, J. R.;

    2014-01-01

    limb. Sixty female Wistar rats, 14 weeks old, were divided into the following groups: baseline, controls, BTX, BTX+GH, and GH. GH was given at a dosage of 5 mg/kg/d for 4 weeks. Compared with controls, BTX resulted in lower periosteal bone formation rate (BFR/BS,-79%, Pmineral density (a...

  15. Growth, pubertal development, skeletal maturation and bone mass acquisition in athletes.

    Science.gov (United States)

    Georgopoulos, Neoklis A; Markou, Kostas B; Theodoropoulou, Anastasia; Vagenakis, George A; Mylonas, Panagiotis; Vagenakis, Apostolos G

    2004-01-01

    The genetic potentials for growth can be fully expressed only under favourable environmental conditions. Excessive physical training may negatively affect growth, especially during puberty. Sports that require a strict control of energy input in the presence of a high energy output are of particular concern. In gymnastics, a different pattern in skeletal maturation was observed, leading to an attenuation of growth potential ins Artistic Gymnasts (AG), more pronounced in males than in females, whereas in female Rhythmic Gymnasts (RG) the genetic predisposition to growth was preserved because of a late catch-up growth phenomenon. In all other sports not requiring strict dietary restrictions, no deterioration of growth has been documented. Intensive physical training and negative energy balance modify the hypothalamic pituitary set point at puberty, prolong the prepubertal stage and delay pubertal development and menarche in a variety of sports. In elite RG and AG the prepubertal stage is prolonged and pubertal development is entirely shifted to a later age, paralleling the bone age rather than the chronological age. Bone formation, and, consequently, BMD are enhanced by physical activity. In athletes, high-impact loading activities have been shown to improve BMD, while in sports requiring a lean somatotype, the delay in skeletal maturation and pubertal development, resulting from hypoestrogenemia, predisposes athletes to osteopenia. In AG, an increase in bone density is observed using the bone age as denominator.

  16. A genome-wide association analysis implicates SOX6 as a candidate gene for wrist bone mass

    Institute of Scientific and Technical Information of China (English)

    Shawn; LEVY

    2010-01-01

    Osteoporosis is a highly heritable common bone disease leading to fractures that severely impair the life quality of patients.Wrist fractures caused by osteoporosis are largely due to the scarcity of wrist bone mass.Here we report the results of a genome-wide association study (GWAS) of wrist bone mineral density (BMD).We examined ~500000 SNP markers in 1000 unrelated homogeneous Caucasian subjects and found a novel allelic association with wrist BMD at rs11023787 in the SOX6 (SRY (sex determining region Y)-box 6) gene (P=9.00×10-5).Subjects carrying the C allele of rs11023787 in SOX6 had significantly higher mean wrist BMD values than those with the T allele (0.485:0.462 g cm-2 for C allele vs.T allele carriers).For validation,we performed SOX6 association for BMD in an independent Chinese sample and found that SNP rs11023787 was significantly associated with wrist BMD in the Chinese sample (P=6.41×10-3).Meta-analyses of the GWAS scan and the replication studies yielded P-values of 5.20×10-6 for rs11023787.Results of this study,together with the functional relevance of SOX6 in cartilage formation,support the SOX6 gene as an important gene for BMD variation.

  17. Thermal discomfort with cold extremities in relation to age, gender, and body mass index in a random sample of a Swiss urban population

    Directory of Open Access Journals (Sweden)

    Orgül Selim

    2010-06-01

    Full Text Available Abstract Background The aim of this epidemiological study was to investigate the relationship of thermal discomfort with cold extremities (TDCE to age, gender, and body mass index (BMI in a Swiss urban population. Methods In a random population sample of Basel city, 2,800 subjects aged 20-40 years were asked to complete a questionnaire evaluating the extent of cold extremities. Values of cold extremities were based on questionnaire-derived scores. The correlation of age, gender, and BMI to TDCE was analyzed using multiple regression analysis. Results A total of 1,001 women (72.3% response rate and 809 men (60% response rate returned a completed questionnaire. Statistical analyses revealed the following findings: Younger subjects suffered more intensely from cold extremities than the elderly, and women suffered more than men (particularly younger women. Slimmer subjects suffered significantly more often from cold extremities than subjects with higher BMIs. Conclusions Thermal discomfort with cold extremities (a relevant symptom of primary vascular dysregulation occurs at highest intensity in younger, slimmer women and at lowest intensity in elderly, stouter men.

  18. The response of bone to unloading

    Science.gov (United States)

    Bikle, D. D.; Halloran, B. P.

    1999-01-01

    Skeletal unloading leads to decreased bone formation and decreased bone mass. Bone resorption is uncoupled from bone formation, contributing to the bone loss. During spaceflight bone is lost principally from the bones most loaded in the 1-g environment, and some redistribution of bone from the lower extremities to the head appears to take place. Although changes in calcitropic hormones have been demonstrated during skeletal unloading (PTH and 1,25(OH)2D decrease), it remains unclear whether such changes account for or are in response to the changes in bone formation and resorption. Bed rest studies with human volunteers and hindlimb elevation studies with rats have provided useful data to help explain the changes in bone formation during spaceflight. These models of skeletal unloading reproduce a number of the conditions associated with microgravity, and the findings from such studies confirm many of the observations made during spaceflight. Determining the mechanism(s) by which loading of bone is sensed and translated into a signal(s) controlling bone formation remains the holy grail in this field. Such investigations couple biophysics to biochemistry to cell and molecular biology. Although studies with cell cultures have revealed biochemical responses to mechanical loads comparable to that seen in intact bone, it seems likely that matrix-cell interactions underlie much of the mechanocoupling. The role for systemic hormones such as PTH, GH, and 1,25(OH)2D compared to locally produced factors such as IGF-I, PTHrP, BMPs, and TGF-beta in modulating the cellular response to load remains unclear. As the mechanism(s) by which bone responds to mechanical load with increased bone formation are further elucidated, applications of this knowledge to other etiologies of osteoporosis are likely to develop. Skeletal unloading provides a perturbation in bone mineral homeostasis that can be used to understand the mechanisms by which bone mineral homeostasis is maintained, with

  19. 雌激素影响肌力与骨量间的关系%Effect of estrogen on the relation of muscle force and bone mass

    Institute of Scientific and Technical Information of China (English)

    林守清; 王绍海; 孙允高

    2006-01-01

    目的:在研究原发性骨质疏松的发生及防治时,肌力与骨量的关系的影响因素值得关注.本文拟探讨雌激素作为非力学因素影响肌力与骨量之间关系的机制.方法:通过计算机检索肌力与骨量的关系,雌激素对肌力与骨量之间关系的影响的相关文献,结合作者以往的研究工作,论述雌激素对肌力与骨量间关系的影响.结果:肌力决定骨结构和骨量,使骨强度适应运动负荷.雌激素主要通过影响骨应变阈值来调整肌力与骨量之间的关系.雌激素疗法有益于骨组织,部分通过保护肌力实现.结论:雌激素能够影响肌力与骨量的关系,雌激素疗法可能有保护肌力的作用.%AIM: The relationship between muscle force (MF) and bone mass (BM)has become one of the pivotal aspects in research of cause, prevention and treatment of primary osteoporosis. This paper is to probe into the mechanism by which estrogen influences the relationship between MF and BM.METHODS: We searched for the relative papers on the relationship between muscle force and bone mass and the effect of estrogen on relationship between muscle force and bone mass. Combining the literatures with our previous results, we discussed the effects of estrogen on relationship between muscle force and bone mass.RESULTS: Muscle force, which determines bone structure and bone mass,makes bone strength adaptable to work load. Estrogen adjustes adaptability of muscle force and bone mass, mainly by the influence on threshold of bone strain. Estrogen therapy could maintain muscle force, partially by which estrogen exerts the beneficial effects on bone.CONCLUSION: Estrogen could influence the relationship between muscle force and bone mass, and estrogen therapy could have the beneficial effect on muscle force.

  20. Effect of risedronate on the cortical and cancellous bone mass and mechanical properties in ovariectomized rats: a comparison with the effects of alfacalcidol.

    Science.gov (United States)

    Iwamoto, Jun; Seki, Azusa; Takeda, Tsuyoshi; Sato, Yoshihiro; Yamada, Harumoto; Yeh, James K

    2006-12-01

    The purpose of the present study was to compare the effects of risedronate (RIS) and alfacalcidol (ALF) on the cortical and cancellous bone mass and mechanical properties in ovariectomized rats in a head-to-head fashion. Forty female Sprague-Dawley rats, 7 mo of age, were randomized into six groups: the sham-operated control (Sham) group, and five ovariectomized groups: treated with vehicle, RIS (0.1, 1.0, or 2.5 mg/kg, p.o., daily), and ALF (0.5 microg/kg, p.o., daily). At the end of the 8-wk experimental period, bone histomorphometric analyses of the cancellous bone of the proximal tibial metaphysis and cortical bone of the tibial disphysis was performed, and the mechanical properties of the bone were evaluated at the femoral distal metaphysis (FDM) and femoral diaphysis (FD). RIS prevented the decrease in the cancellous bone volume/total tissue volume (BV/TV) noted in ovariectomized rats in a dose-dependent manner, by suppressing increases in cancellous bone formation and resorption, without any apparent effect on the Ct Ar or maximum load of the FDM or FD. On the other hand, ALF increased the cancellous BV/TV, Ct Ar, and maximum load of the FDM or FD, by mildly decreasing cancellous bone formation and resorption, increasing periosteal and endocortical bone formation, and preventing an increase in endocortical bone resorption. Thus, the present study clearly showed that RIS and ALF had differential effects on the cortical and cancellous bone mass and mechanical properties in ovariectomized rats.

  1. Anthropometric and lifestyle associations of bone mass in healthy pre-menopausal Mexican and Asian American women.

    Science.gov (United States)

    Crespo, Noe C; Yoo, Eun Jung; Hawkins, Steven A

    2011-02-01

    Few studies have established the lifestyle predictors of peak bone mineral density (BMD) in Mexican-American (MA) and Asian-American (AA) women. Pre-menopausal MA (n = 48) and AA (n = 58) women aged 30-45 years old were tested for BMD, body composition, aerobic fitness, and muscle function. Socio-demographic characteristics, health status, prevalence of osteoporosis risk factors, physical activity, and diet were determined via questionnaire. Pearson's correlations and multiple linear regressions were used to test the associations between various osteoporosis risk factors and BMD. Body composition, anthropometric, and BMD differences were noted between groups. Hip, but not spine BMD, remained significantly higher for the MA compared to the AA group after adjustment for age, BMI, income, and physical activity index. Lean body mass was a significant predictor of hip BMD for both groups and this relationship was stronger for the AA group. Lean body mass may explain ethnic differences in BMD.

  2. Dlk1/FA1 is a novel endocrine regulator of bone and fat mass and its serum level is modulated by growth hormone

    DEFF Research Database (Denmark)

    Abdallah, Basem; Ding, Ming; Jensen, Charlotte H

    2007-01-01

    Fat and bone metabolism are two linked processes regulated by several hormonal factors. Fetal antigen 1 (FA1) is the soluble form of dlk1 (delta-like 1), which is a member of the Notch-Delta family. We previously identified FA1 as a negative regulator of bone marrow mesenchymal stem cell...... differentiation. Here, we studied the effects of circulating FA1 on fat and bone mass in vivo by generating mice expressing high serum levels of FA1 (FA1 mice) using the hydrodynamic-based gene transfer procedure. We found that increased serum FA1 levels led to a significant reduction in total body weight, fat...... mass, and bone mass in a dose-dependent manner. Reduced bone mass in FA1 mice was associated with the inhibition of mineral apposition rate and bone formation rates by 58 and 72%, respectively. Because FA1 is colocalized with GH in the pituitary gland, we explored the possible modulation of serum FA1...

  3. Importance of bioavailable calcium drinking water for the maintenance of bone mass in post-menopausal women.

    Science.gov (United States)

    Costi, D; Calcaterra, P G; Iori, N; Vourna, S; Nappi, G; Passeri, M

    1999-12-01

    The aim of this research was to establish the importance of calcium intake through mineral water on vertebral bone density in women. To this purpose, we examined 255 women divided into two groups: those regularly drinking a high calcium content mineral water (group A; no.=175) and those using different type of water with a lower calcium content (group B; no.=80). Their dietary daily calcium intake was determined by means of a validated questionnaire (N.I.H. Consensus statement) and vertebral bone density was measured by Dual-Energy X-ray absorptiometry (Unigamma-plus ACN densitometer). Women in group A ingested a significantly higher quantity of calcium in water than women in group B (mean difference 258 mg; 95% confidence limits: 147-370 mg). The average bone density values were slightly but significantly higher in group A as compared to group B (mean+/-SD: 1.044+0,15 vs 1.002+0,14; p=0.03). In addition to age, BMI and menopausal status, calcium intake was a significant predictor of spinal BMD. These 4 variables explained about 35% of the spinal BMD variance. When the analysis was repeated separately for pre- and post-menopausal subjects, calcium remained a significant predictor in post-menopausal women (t=2.28; p=0.02), but not in premenopausal women. These results underline the importance of a lifelong daily calcium intake, resulting by the regular drinking of high bioavailable calcium water, in order to maintain bone mass after the menopause, in comparison to the use of a lower content calcium water.

  4. [Relation between calcaneal bone mass and lifestyles in young adult women. Influence of experience of delivery and months post delivery].

    Science.gov (United States)

    Koitaya, N; Ishikawa, K; Oota, T; Yoshimoto, K; Tanaka, S; Ezawa, I

    1999-11-01

    The aim of this study was to clarify the cross-sectional relation between calcaneal bone mass and lifestyles in healthy pre-menopausal young adult women classified by the experience of pregnancy and the months after delivery. The 457 healthy Japanese women aged 20-39 years living in an urban community underwent a health check up for osteoporosis. Calcaneal bone was measured by ultrasound using the Lunar Achilles, and stiffness was used as an index of bone mass. The information on pregnancy, delivery and lactation, and lifestyles including past and current exercise and frequency of food consumption were collected by a questionnaire. In addition, two-day dietary records were obtained to assess the nutrient intake, and seven-day walking records as an index of physical activities. These subjects were divided into 3 groups according to the experience of pregnancy, and the time after delivery (subgroups of no experience of pregnancy, 12-35 months post-delivery and 36 months or more post-delivery), and the relation between stiffness index and lifestyle factors was examined in the 3 groups. 1) Stiffness correlated significantly with experience of pregnancy, age at menarche, current exercise and frequency of intake of dairy products. 2) In the group without experience of pregnancy, stiffness in women with current exercise habit was significantly higher than women without the habit. Those with past exercise habit, current milk consumption and current calcium intake showed relatively greater stiffness. 3) In the 12-35 months post-delivery group, there was no relation of past and current physical activity to stiffness. For women whose frequency of milk consumption or daily calcium intake were high, the stiffness was significantly greater. In addition, past milk consumption and current frequency of dairy products consumption tended to show higher stiffness. 4) In 36 months or more post-delivery group, women with current exercise habit exhibited significantly higher stiffness

  5. Relationship between Body Mass Composition, Bone Mineral Density, Skin Fibrosis and 25(OH Vitamin D Serum Levels in Systemic Sclerosis.

    Directory of Open Access Journals (Sweden)

    Addolorata Corrado

    Full Text Available A reduced bone mineral density (BMD is observed in several rheumatic autoimmune diseases, including Systemic Sclerosis (SSc; nevertheless, data concerning the possible determinants of bone loss in this disease are not fully investigated. The aim of this study is to evaluate the relationship between BMD, body mass composition, skin sclerosis and serum Vitamin D levels in two subsets of SSc patients. 64 post-menopausal SSc patients, classified as limited cutaneous (lcSSc or diffuse cutaneous (dcSSc SSc, were studied. As control, 35 healthy post-menopausal women were recruited. Clinical parameters were evaluated, including the extent of skin involvement. BMD at lumbar spine, hip, femoral neck and body mass composition were determined by dual-energy X-ray absorptiometry. Serum calcium, phosphorus, alkaline phosphatase, urine pyridinium cross-links, intact parathyroid hormone and 25-hydroxyvitamin D (25OHD were measured. BMD at spine, femoral neck and total hip was significantly lower in SSc patients compared to controls. In dcSSc subset, BMD at spine, femoral neck and total hip was significantly lower compared to lcSSc. No differences in both fat and lean mass were found in the three study groups even if patients with dcSSc showed a slightly lower total body mass compared to healthy controls. Total mineral content was significantly reduced in dSSc compared to both healthy subjects and lcSSc group. Hypovitaminosis D was observed both in healthy post-menopausal women and in SSc patients, but 25OHD levels were significantly lower in dcSSc compared to lcSSc and inversely correlated with the extent of skin thickness. These results support the hypothesis that the extent of skin involvement in SSc patients could be an important factor in determining low circulating levels of 25OHD, which in turn could play a significant role in the reduction of BMD and total mineral content.

  6. G(–2548A leptin gene polymorphism in obese subjects is associated with serum leptin concentration and bone mass

    Directory of Open Access Journals (Sweden)

    Edward Franek

    2010-05-01

    Full Text Available INTRODUCTION: Clinical studies have shown either positive or in some other cases negative correlations between leptinemia and bone mineral density (BMD or bone mineral content (BMC. OBJECTIVES: The aim of the present study was to assess whether these discrepancies might be associated with the effect of G(–2548A leptin or A326G and A668G leptin receptor gene polymorphisms on serum leptin concentrations or BMD and BMC. PATIENTS AND METHODS: The study included 72 obese patients (39 women and 33 men, aged 46 ±8.8 years; body mass index [BMI] >30 kg/m2. In all subjects, serum creatinine, glucose, lipids, leptin, and insulin were determined. Total fat mass (TFM, BMC, and BMD were assessed using dual energy X‑ray absorptiometry (Lunar DPX-L. RESULTS: No significant correlations were observed between body mass composition parameters (TFM, lean mass, BMC or BMD in relation to genotypes. A positive correlation was found between serum leptin concentration and BMI. An inverse association was observed between leptin concentrations and BMC. Multiple regression analysis showed independent correlations of leptinemia with sex (P <0.001, TFM (P <0.000 001, BMC (P = 0.0001, and the presence of (–2548A allele of the leptin gene (P <0.05. These parameters together accounted for 83% of variability in serum leptin concentrations. CONCLUSIONS: In obese patients, serum leptin concentration shows an independent inverse correlation with BMD and male sex, but positively with TFM and the presence of –2548A allele of leptin gene. These parameters are responsible for 83% of leptin concentration variability. No correlations between the examined polymorphisms and BMC or BMD were found.

  7. The Effect of Selected Walking Program on Bone Mass Density Body Composition and Serum Estrogen in OBESE Girls

    Directory of Open Access Journals (Sweden)

    Seyed Nasim Habibzadeh

    2009-01-01

    Full Text Available Introduction: Osteoporosis and obesity two disorders of body composition are growing in prevalence. This is while a few studies have investigated the relationship between body composition and bone mass density (BMD with physical activity in obese girls. Thus this study aims at investigating the effect of walking programs in preventing osteoporosis and reducing obesity in obese girls. Methods: Twenty non-athlete obese girls volunteered to take part in this research. The participants then were randomly divided into two groups (Control: n=10 BMI=30.9±3.6 kg/m2 and experimental: n=10 BMI=30.2±1.8 kg/m2. The bone mass density body composition and serum estrogen of the participants were measured initially and after two months. Then the experimental group started a two-month exercise program which consisted of 30 minutes of walking with intensity of %50- %75 of heart rate three times a week. The data were analyzed through independent t-test (P

  8. Efficacy of estrogen replacement therapy (ERT) on uterine growth and acquisition of bone mass in patients with Turner syndrome.

    Science.gov (United States)

    Nakamura, Tomomi; Tsuburai, Taku; Tokinaga, Aya; Nakajima, Izumi; Kitayama, Reiko; Imai, Yuichi; Nagata, Tomoko; Yoshida, Hiroshi; Hirahara, Fumiki; Sakakibara, Hideya

    2015-01-01

    Estrogen replacement therapy (ERT) is necessary for uterine development and bone mass acquisition in women with Turner syndrome (TS) suffering from ovarian insufficiency. However, adequate ERT regimens have not yet been established. The aim of this study was to evaluate the efficacy of ERT for both uterine development and bone mass acquisition. One hundred TS patients from Yokohama City University Hospital (88 with primary amenorrhea (PA) and 12 patients with spontaneous menstrual cycles (MC)) were enrolled after obtaining consent. Clinical profiles, uterine length (UL) measured by ultrasonic examination, and bone mineral density (BMD) of the lumbar vertebrae (L2-4) assessed by DEXA were evaluated. At the time of the first visit, the ULs of patients in the PA group were significantly shorter than those in the MC group. After receiving ERT, there were no significant differences in UL between patients with PA and MC. Forty-seven patients for whom the ERT initiation age was known were investigated to clarify the influence on BMD. The results showed that the BMD in the late initiation (18 years or older) group at the latest visit (0.770 ± 0.107 g/cm2: n = 16) was significantly lower than that in the early initiation (under 18 years) group (0.858 ± 0.119 g/cm2: n = 21) or the MC group (0.941 ± 0.118 g/cm2: n = 10). No significant differences were seen between the early initiation and MC group. ERT was effective in increasing UL and BMD. However, early initiation of ERT is necessary to increase BMD.

  9. Anorexia nervosa and bone

    National Research Council Canada - National Science Library

    Misra, Madhusmita; Klibanski, Anne

    2014-01-01

    Anorexia nervosa (AN) is a condition of severe low weight that is associated with low bone mass, impaired bone structure, and reduced bone strength, all of which contribute to increased fracture risk...

  10. Effect of hemiplegia on bone mass and soft tissue body composition

    Energy Technology Data Exchange (ETDEWEB)

    Iversen, E.; Hassager, C.; Christiansen, C.

    1989-01-01

    The content of bone mineral (BMC), lean tissue, and fat tissue were measured by single and dual photon absorptiometry in both the paretic and the nonparetic limbs of 15 patients, hemiplegic due to cerebrovascular accident 23-38 weeks earlier. Compared with the non-paretic arm, the paretic arm had approximately 10% lower (P < 0.01) BMC. This difference was largest at the measuring site with the highest ratio of trabecular to compact bone. The paretic leg had a 4% (P < 0.001) lower BMC than the non-paretic leg. For both the arms and the legs, the lean content was lower (P < 0.05) and the fat content higher (P < 0.01) in the paretic than in the non-paretic. This was relatively more pronounced in the arms than in the legs. We conclude that partial immobilization, owing to parasis after a cerebrovascular accident, results in characteristic changes in the affected limbs, with a marked decrease in the content of bone and lean tissue and a pronounced increase in fatty tissue.

  11. Do Estrogens improve bone mass in osteoporotic women over ten years of menopause

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    Vera Lucia Szejnfeld

    Full Text Available A retrospective analysis of 24 patients with established osteoporosis and with ten or more years of menopause treated with conjugated estrogen, progesterone and calcium followed for one year has been performed. Treated women received 0.625 mg/day of conjugated estrogen from day 1 to 25, 5 mg/day of medroxiprogesterone from day 13 to 25, of each cycle, plus calcium (500 - 1000 mg/day, during one year (12 cycles. As control group was used 18 age-matched that received only calcium (500 a 1000 mg/day. All patients had at least two dual-photon spine and proximal femur (neck, Ward's triangle and trocanter densities measurements performed 12 months apart. Estrogen treatment was associated with increased bone mineral density at spine and trocanter. Control group did not present any statistically change after one year in any site studied. We concluded that women with ten or more years of menopause and established osteoporosis treated with replacement hormonal therapy and calcium results in improvement of bone mineral density. These data support that women with ten or more years of menopause respond to estrogen replacement therapy with absolute increments in bone density similar to those seen in younger women, in the early menopause.

  12. Evidence for reduced cancellous bone mass in the spontaneously hypertensive rat

    Science.gov (United States)

    Wang, T. M.; Hsu, J. F.; Jee, W. S.; Matthews, J. L.

    1993-01-01

    The histomorphometric changes in the proximal tibial metaphysis and epiphyseal growth plate and midtibial shaft of 26-week-old spontaneously hypertensive rats (SHR) compared with those of the corresponding normotensive Wistar-Kyoto (WKY) rats were studied. A decrease in body weight, growth plate thickness, and longitudinal growth rate of the proximal tibial epiphysis, trabecular bone volume, trabecular thickness and number, the number of osteoblasts and osteoprogenitor cells per millimeter square surface of the proximal tibial metaphysis, periosteal and endocortical apposition rate and bone formation rate of the tibial diaphysis were observed in the SHR. Additionally, systolic blood pressure, the number of osteoclasts per millimeter square surface and average number of nuclei per osteoclast of the proximal tibial metaphysis were significantly increased. Thus, osteoclastic activity is dominant over osteoblastic and chondroblastic activity in the SHR that results in a cancellous bone deficit in the skeleton. It will require additional work to ascertain the underlying cause for this condition as several factors in the SHR with a potential for causing this change are present, including elevated parathyroid hormone (PTH), depressed 1,25-(OH)2D3, low calcium absorption, reduced body weight (reduced loading) elevated blood pressure and possibly other direct cell differences in the mutant strain. At present elevated PTH and adaptation to underloading from reduced weight are postulated to be a likely cause, but additional studies are required to test this interpretation.

  13. Osteoblast-targeted overexpression of TAZ increases bone mass in vivo.

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    Jae-Yeon Yang

    Full Text Available Osteoblasts are derived from mesenchymal progenitors. Differentiation to osteoblasts and adipocytes is reciprocally regulated. Transcriptional coactivator with a PDZ-binding motif (TAZ is a transcriptional coactivator that induces differentiation of mesenchymal cells into osteoblasts while blocking differentiation into adipocytes. To investigate the role of TAZ on bone metabolism in vivo, we generated transgenic mice that overexpress TAZ under the control of the procollagen type 1 promoter (Col1-TAZ. Whole body bone mineral density (BMD of 6- to 19-week-old Col-TAZ mice was 4% to 7% higher than that of their wild-type (WT littermates, whereas no difference was noticed in Col.1-TAZ female mice. Microcomputed tomography analyses of proximal tibiae at 16 weeks of age demonstrated a significant increase in trabecular bone volume (26.7% and trabecular number (26.6% with a reciprocal decrease in trabecular spacing (14.2% in Col1-TAZ mice compared with their WT littermates. In addition, dynamic histomorphometric analysis of the lumbar spine revealed increased mineral apposition rate (42.8% and the serum P1NP level was also significantly increased (53% in Col.1-TAZ mice. When primary calvaria cells were cultured in osteogenic medium, alkaline phosphatase (ALP activity was significantly increased and adipogenesis was significantly suppressed in Col1-TAZ mice compared with their WT littermates. Quantitative real-time polymerase chain reaction analyses showed that expression of collagen type 1, bone sialoprotein, osteocalcin, ALP, osterix, and Runx2 was significantly increased in calvaria cells from Col1-TAZ mice compared to their WT littermates. In vitro, TAZ enhanced Runx2-mediated transcriptional activity while suppressing the peroxisome proliferator-activated receptor gamma signaling pathway. TAZ also enhanced transcriptional activity from 3TP-Lux, which reflects transforming growth factor-beta (TGF-β-mediated signaling. In addition, TAZ enhanced TGF

  14. Species identification by analysis of bone collagen using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry.

    Science.gov (United States)

    Buckley, Michael; Collins, Matthew; Thomas-Oates, Jane; Wilson, Julie C

    2009-12-01

    Species identification of fragmentary bone, such as in rendered meat and bone meal or from archaeological sites, is often difficult in the absence of clear morphological markers. Here we present a robust method of analysing genus-specific collagen peptides by mass spectrometry simply by using solid-phase extraction (a C18 ZipTip) for peptide purification, rather than liquid chromatography/mass spectrometry (LC/MS). Analysis of the collagen from 32 different mammal species identified a total of 92 peptide markers that could be used for species identification, for example, in processed food and animal feed. A set of ancient (>100 ka@10 degrees C) bone samples was also analysed to show that the proposed method has applications to archaeological bone identification.

  15. Total body fat percentage and body mass index and the association with lower extremity injuries in children

    DEFF Research Database (Denmark)

    Jespersen, Eva; Verhagen, Evert; Holst, René;

    2014-01-01

    Overweight youths are generally recognised as being at increased risk of sustaining lower extremity injuries in sports. However, previous studies are inconclusive and choices for measuring overweight are manifold....

  16. Alterations of mass density and 3D osteocyte lacunar properties in bisphosphonate-related osteonecrotic human jaw bone, a synchrotron µCT study.

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    Bernhard Hesse

    Full Text Available Osteonecrosis of the jaw, in association with bisphosphonates (BRONJ used for treating osteoporosis or cancer, is a severe and most often irreversible side effect whose underlying pathophysiological mechanisms remain largely unknown. Osteocytes are involved in bone remodeling and mineralization where they orchestrate the delicate equilibrium between osteoclast and osteoblast activity and through the active process called osteocytic osteolysis. Here, we hypothesized that (i changes of the mineralized tissue matrix play a substantial role in the pathogenesis of BRONJ, and (ii the osteocyte lacunar morphology is altered in BRONJ. Synchrotron µCT with phase contrast is an appropriate tool for assessing both the 3D morphology of the osteocyte lacunae and the bone matrix mass density. Here, we used this technique to investigate the mass density distribution and 3D osteocyte lacunar properties at the sub-micrometer scale in human bone samples from the jaw, femur and tibia. First, we compared healthy human jaw bone to human tibia and femur in order to assess the specific differences and address potential explanations of why the jaw bone is exclusively targeted by the necrosis as a side effect of BP treatment. Second, we investigated the differences between BRONJ and control jaw bone samples to detect potential differences which could aid an improved understanding of the course of BRONJ. We found that the apparent mass density of jaw bone was significantly smaller compared to that of tibia, consistent with a higher bone turnover in the jaw bone. The variance of the lacunar volume distribution was significantly different depending on the anatomical site. The comparison between BRONJ and control jaw specimens revealed no significant increase in mineralization after BP. We found a significant decrease in osteocyte-lacunar density in the BRONJ group compared to the control jaw. Interestingly, the osteocyte-lacunar volume distribution was not altered after

  17. Prader-Willi Critical Region, a Non-Translated, Imprinted Central Regulator of Bone Mass: Possible Role in Skeletal Abnormalities in Prader-Willi Syndrome.

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    Ee-Cheng Khor

    Full Text Available Prader-Willi Syndrome (PWS, a maternally imprinted disorder and leading cause of obesity, is characterised by insatiable appetite, poor muscle development, cognitive impairment, endocrine disturbance, short stature and osteoporosis. A number of causative loci have been located within the imprinted Prader-Willi Critical Region (PWCR, including a set of small non-translated nucleolar RNA's (snoRNA. Recently, micro-deletions in humans identified the snoRNA Snord116 as a critical contributor to the development of PWS exhibiting many of the classical symptoms of PWS. Here we show that loss of the PWCR which includes Snord116 in mice leads to a reduced bone mass phenotype, similar to that observed in humans. Consistent with reduced stature in PWS, PWCR KO mice showed delayed skeletal development, with shorter femurs and vertebrae, reduced bone size and mass in both sexes. The reduction in bone mass in PWCR KO mice was associated with deficiencies in cortical bone volume and cortical mineral apposition rate, with no change in cancellous bone. Importantly, while the length difference was corrected in aged mice, consistent with continued growth in rodents, reduced cortical bone formation was still evident, indicating continued osteoblastic suppression by loss of PWCR expression in skeletally mature mice. Interestingly, deletion of this region included deletion of the exclusively brain expressed Snord116 cluster and resulted in an upregulation in expression of both NPY and POMC mRNA in the arcuate nucleus. Importantly, the selective deletion of the PWCR only in NPY expressing neurons replicated the bone phenotype of PWCR KO mice. Taken together, PWCR deletion in mice, and specifically in NPY neurons, recapitulates the short stature and low BMD and aspects of the hormonal imbalance of PWS individuals. Moreover, it demonstrates for the first time, that a region encoding non-translated RNAs, expressed solely within the brain, can regulate bone mass in health

  18. Missense Mutations in LRP5 Associated with High Bone Mass Protect the Mouse Skeleton from Disuse- and Ovariectomy-Induced Osteopenia

    Science.gov (United States)

    Niziolek, Paul J.; Bullock, Whitney; Warman, Matthew L.; Robling, Alexander G.

    2015-01-01

    The low density lipoprotein receptor-related protein-5 (LRP5), a co-receptor in the Wnt signaling pathway, modulates bone mass in humans and in mice. Lrp5 knock-out mice have severely impaired responsiveness to mechanical stimulation whereas Lrp5 gain-of-function knock-in and transgenic mice have enhanced responsiveness to mechanical stimulation. Those observations highlight the importance of Lrp5 protein in bone cell mechanotransduction. It is unclear if and how high bone mass-causing (HBM) point mutations in Lrp5 alter the bone-wasting effects of mechanical disuse. To address this issue we explored the skeletal effects of mechanical disuse using two models, tail suspension and Botulinum toxin-induced muscle paralysis, in two different Lrp5 HBM knock-in mouse models. A separate experiment employing estrogen withdrawal-induced bone loss by ovariectomy was also conducted as a control. Both disuse stimuli induced significant bone loss in WT mice, but Lrp5 A214V and G171V were partially or fully protected from the bone loss that normally results from disuse. Trabecular bone parameters among HBM mice were significantly affected by disuse in both models, but these data are consistent with DEXA data showing a failure to continue growing in HBM mice, rather than a loss of pre-existing bone. Ovariectomy in Lrp5 HBM mice resulted in similar protection from catabolism as was observed for the disuse experiments. In conclusion, the Lrp5 HBM alleles offer significant protection from the resorptive effects of disuse and from estrogen withdrawal, and consequently, present a potential mechanism to mimic with pharmaceutical intervention to protect against various bone-wasting stimuli. PMID:26554834

  19. Missense Mutations in LRP5 Associated with High Bone Mass Protect the Mouse Skeleton from Disuse- and Ovariectomy-Induced Osteopenia.

    Science.gov (United States)

    Niziolek, Paul J; Bullock, Whitney; Warman, Matthew L; Robling, Alexander G

    2015-01-01

    The low density lipoprotein receptor-related protein-5 (LRP5), a co-receptor in the Wnt signaling pathway, modulates bone mass in humans and in mice. Lrp5 knock-out mice have severely impaired responsiveness to mechanical stimulation whereas Lrp5 gain-of-function knock-in and transgenic mice have enhanced responsiveness to mechanical stimulation. Those observations highlight the importance of Lrp5 protein in bone cell mechanotransduction. It is unclear if and how high bone mass-causing (HBM) point mutations in Lrp5 alter the bone-wasting effects of mechanical disuse. To address this issue we explored the skeletal effects of mechanical disuse using two models, tail suspension and Botulinum toxin-induced muscle paralysis, in two different Lrp5 HBM knock-in mouse models. A separate experiment employing estrogen withdrawal-induced bone loss by ovariectomy was also conducted as a control. Both disuse stimuli induced significant bone loss in WT mice, but Lrp5 A214V and G171V were partially or fully protected from the bone loss that normally results from disuse. Trabecular bone parameters among HBM mice were significantly affected by disuse in both models, but these data are consistent with DEXA data showing a failure to continue growing in HBM mice, rather than a loss of pre-existing bone. Ovariectomy in Lrp5 HBM mice resulted in similar protection from catabolism as was observed for the disuse experiments. In conclusion, the Lrp5 HBM alleles offer significant protection from the resorptive effects of disuse and from estrogen withdrawal, and consequently, present a potential mechanism to mimic with pharmaceutical intervention to protect against various bone-wasting stimuli.

  20. Gracile bone dysplasias

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, Kazimierz [Department of Medical Imaging, The Children' s Hospital at Westmead, Locked Bag 4001, Westmead 2145, NSW (Australia); Masel, John [Department of Radiology, Royal Children' s Hospital, Brisbane (Australia); Sillence, David O. [Department of Paediatrics and Child Health, The University of Sydney (Australia); Arbuckle, Susan [Department of Anatomical Pathology, The Children' s Hospital at Westmead, NSW (Australia); Juttnerova, Vera [Oddeleni Lekarske Genetiky, Hradec Kralove (Czech Republic)

    2002-09-01

    Gracile bone dysplasias constitute a group of disorders characterised by extremely slender bones with or without fractures. We report four newborns, two of whom showed multiple fractures. Two babies had osteocraniostenosis and one had features of oligohydramnios sequence. The diagnosis in the fourth newborn, which showed thin long bones and clavicles and extremely thin, poorly ossified ribs, is uncertain. Exact diagnosis of a gracile bone dysplasia is important for genetic counselling and medico-legal reasons. (orig.)

  1. Low calcium-phosphate intakes modulate the low-protein diet-related effect on peak bone mass acquisition: a hormonal and bone strength determinants study in female growing rats.

    Science.gov (United States)

    Fournier, C; Rizzoli, R; Ammann, P

    2014-11-01

    Peak bone mass acquisition is influenced by environmental factors including dietary intake. A low-protein diet delays body and skeletal growth in association with a reduction in serum IGF-1 whereas serum FGF21 is increased by selective amino acid deprivation. Calcium (Ca) and phosphorous (P) are also key nutrients for skeletal health, and inadequate intakes reduce bone mass accrual in association with calciotropic hormone modulation. Besides, the effect of calcium supplementation on bone mass in prepubertal children appears to be influenced by protein intake. To further explore the interaction of dietary protein and Ca-P intake on bone growth, 1-month-old female rats were fed with an isocaloric 10%, 7.5%, or 5% casein diet containing normal or low Ca-P for an 8-week period (6 groups). Changes in tibia geometry, mineral content, microarchitecture, strength, and intrinsic bone quality were analyzed. At the hormonal level, serum IGF-1, fibroblast growth factor 21 (FGF21), PTH, 1,25-dihydroxyvitamin D3 (calcitriol), and FGF23 were investigated as well as the Ghr hepatic gene expression. In normal dietary Ca-P conditions, bone mineral content, trabecular and cortical bone volume, and bone strength were lower in the 5% casein group in association with a decrease in serum IGF-1 and an increase in FGF21 levels. Unexpectedly, the low-Ca-P diet attenuated the 5% casein diet-related reduction of serum IGF-1 and Ghr hepatic gene expression, as well as the low-protein diet-induced decrease in bone mass and strength. However, this was associated with lower cortical bone material level properties. The low-Ca-P diet increased serum calcitriol but decreased FGF23 levels. Calcitriol levels positively correlated with Ghr hepatic mRNA levels. These results suggest that hormonal modulation in response to a low-Ca-P diet may modify the low-protein diet-induced effect on Ghr hepatic mRNA levels and consequently the impact of low protein intakes on IGF-1 circulating levels and skeletal

  2. Effect of sex-hormone levels, sex, body mass index and other host factors on human craniofacial bone regeneration with bioactive tricalcium phosphate grafts.

    Science.gov (United States)

    Knabe, Christine; Mele, Aynur; Kann, Peter Herbert; Peleska, Barbara; Adel-Khattab, Doaa; Renz, Harald; Reuss, Alexander; Bohner, Marc; Stiller, Michael

    2017-04-01

    Little is known regarding the associations between sex-hormone levels, sex, body mass index (BMI), age, other host factors and biomaterial stimulated bone regeneration in the human craniofacial skeleton. The aim of this study was to elucidate the associations between these factors and bone formation after sinus floor augmentation procedures (SFA) utilizing a bioactive tricalcium phosphate (TCP) bone grafting material. We conducted a prospective study in a human population in which 60 male and 60 female participants underwent SFA and dental implant placement using a staged approach. BMI as well as levels of serum estradiol (E2), total testosterone (TT), and the free androgen index (FAI) were measured by radioimmunoassay and electrochemoluminescent-immunoassay. At implant placement, 6 months after SFA, bone biopsy specimens were harvested for hard tissue histology, the amount of bone formation was evaluated by histomorphometry and immunohistochemical analysis of osteogenic marker expression. The Wilcoxon rank-sum U test, Spearman correlations and linear regression analysis were used to explore the association between bone formation and BMI, hormonal and other host factors. BMI and log E2 were significantly positively associated with bone formation in male individuals (p BMI enhanced TCP stimulated craniofacial i.e. intramembranous bone repair. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. A comparison of principal component analysis, partial least-squares and reduced-rank regressions in the identification of dietary patterns associated with bone mass in ageing Australians.

    Science.gov (United States)

    Melaku, Yohannes Adama; Gill, Tiffany K; Taylor, Anne W; Adams, Robert; Shi, Zumin

    2017-06-12

    The relative advantages of dietary analysis methods, particularly in identifying dietary patterns associated with bone mass, have not been investigated. We evaluated principal component analysis (PCA), partial least-squares (PLS) and reduced-rank regressions (RRR) in determining dietary patterns associated with bone mass. Data from 1182 study participants (45.9% males; aged 50 years and above) from the North West Adelaide Health Study (NWAHS) were used. Dietary data were collected using a food frequency questionnaire (FFQ). Dietary patterns were constructed using PCA, PLS and RRR and compared based on the performance to identify plausible patterns associated with bone mineral density (BMD) and content (BMC). PCA, PLS and RRR identified two, four and four dietary patterns, respectively. All methods identified similar patterns for the first two factors (factor 1, "prudent" and factor 2, "western" patterns). Three, one and none of the patterns derived by RRR, PLS and PCA were significantly associated with bone mass, respectively. The "prudent" and dairy (factor 3) patterns determined by RRR were positively and significantly associated with BMD and BMC. Vegetables and fruit pattern (factor 4) of PLS and RRR was negatively and significantly associated with BMD and BMC, respectively. RRR was found to be more appropriate in identifying more (plausible) dietary patterns that are associated with bone mass than PCA and PLS. Nevertheless, the advantage of RRR over the other two methods (PCA and PLS) should be confirmed in future studies.

  4. The Effect of Glucocorticoids on Bone Mass in Patients with Asthma and Chronic obstructive Pulmonary Disease

    Directory of Open Access Journals (Sweden)

    Evrim Karadağ Saygı

    2005-06-01

    Full Text Available Inhaled corticosteroids and bronchodilators have become a key element in the maintenance treatment of bronchial asthma and chronic obstructive pulmanory disease (COPD. It is well known that long-term systemic steroid use causes osteoporosis, whereas inhaled corticosteroids and bronchodilators have been discussed to be cause of such side-affect. The aim of this study was to detect the effect of long term inhaled/oral steroids and bronchodilators on bone mineral density (BMD with asthma and COPD. Fifty-three patients with bronchial asthma (n=44 and COPD (n=9 were enrolled in this study. BMD were measured and risk factors for osteoporosis were detected. BMD measurements of lumbar area of the spine (L2-4, neck of femur and femoral ward’s triangle zone were performed by the dual energy x-ray absorptiometer (LUNAR. 53 patients evaluated in three groups according to treatment type; 26 patients were using inhaled corticosteroids and bronchodilators (group 1, 18 patients were using only bronchodilators (group 2 and 9 patients were using (group 3 oral corticosteroids and bronchodilators. There were significant differences between group 3 and other two groups in terms of BMD, T and Z scores of the lumbar and femoral neck (p0.05. As a result, we suggest that systemic corticosteroids negatively affect bone mineral density more than inhaled corticosteroids in patients with COPD.

  5. Calcium and vitamin D requirements for optimal bone mass during adolescence.

    Science.gov (United States)

    Abrams, Steven A

    2011-11-01

    There remains very strong interest in the calcium and vitamin D requirements of adolescents related to bone health. The Institute of Medicine (IOM) released new dietary guidelines in late 2010 for these nutrients. These guidelines were primarily based on literature published in 2009 and earlier and emphasized the role of vitamin D combined with calcium in optimizing bone health. A series of research studies published in 2010 and 2011, mostly not included in the IOM report, have further addressed these issues. These most recently published data are generally consistent with the IOM report and earlier data in supporting calcium intakes of 1300 mg/day and vitamin D intakes of 600 IU/day for adolescents. However, there is some suggestion that a slightly higher Recommended Dietary Allowance for vitamin D might be considered at some future time. New dietary guidelines and recent research support increased vitamin D intakes compared with previous recommendations, but not very high doses. Further studies are needed related to high-dose vitamin D intake.

  6. Overview of calpain-mediated regulation of bone and fat mass in osteoblasts.

    Science.gov (United States)

    Shimada, Masako

    2013-05-01

    The receptor for parathyroid hormone (PTH) and PTH-related peptide (PTH1R) belongs to the class II G protein-coupled receptor superfamily. The calpain small subunit encoded by the gene Capns1 is the second protein and the first enzyme identified by a yeast two-hybrid screen using the intracellular C-terminal tail of the rat PTH1R. The calpain regulatory small subunit forms a heterodimer with the calpain large catalytic subunit and modulates various cellular functions as a cysteine protease. To investigate a physiological role of the calpain small subunit in cells of the osteoblast lineage, we generated osteoblast-specific Capns1 knockout mouse models and characterized their bone phenotype. Molecular mechanisms by which calpain modulates cell proliferation of the osteoblast lineage were further examined in vitro. Moreover, we utilized the mutant mice as a disease model of osteoporosis accompanied with impaired bone resorptive function and suggested a possible clinical translation of our basic research finding.

  7. Evaluation of Round Window Stimulation Using the Floating Mass Transducer by Intracochlear Sound Pressure Measurements in Human Temporal Bones

    Science.gov (United States)

    Nakajima, Hideko Heidi; Dong, Wei; Olson, Elizabeth S.; Rosowski, John J.; Ravicz, Michael E.; Merchant, Saumil N.

    2009-01-01

    Hypothesis Round window (RW) stimulation with a floating mass transducer (FMT) can be studied experimentally and optimized to enhance auditory transduction. Background The FMT (MED-EL Vibrant Soundbridge) has been recently implanted in patients with refractory conductive or mixed hearing loss to stimulate the RW with varying degrees of success. The mechanics of RW stimulation with the FMT have not been studied in a systematic manner. Methods In cadaveric human temporal bones, measurements of stapes velocity with laser vibrometry in response to FMT-RW stimulation were used to optimize FMT insertion. The effect of RW stimulation on hearing was estimated using simultaneous measurements of intracochlear pressures in both perilymphatic scalae with micro-optical pressure transducers. This enabled calculation of the differential pressure across the cochlear partition, which is directly tied to auditory transduction. Results The best coupling between the FMT and RW was achieved with a piece of fascia placed between the RW and the FMT, and by "bracing" the free end of the FMT against the hypotympanic wall with dental impression material. FMT-RW stimulation provided differential pressures comparable to sound-induced oval window stimulation above 1 kHz. However, below 1 kHz the FMT was less capable. Conclusions Measurements of stapes velocity and intracochlear sound pressures in scala vestibuli and scala tympani enabled experimental evaluation of FMT stimulation of the RW. The efficacy of FMT-RW coupling was influenced significantly by technical and surgical factors, which can be optimized. This temporal bone preparation also lays the foundation for future studies to investigate multiple issues of relevance to both basic and clinical science such as RW stimulation in stapes fixation, non-aerated middle-ears and third-window lesions, and to answer basic questions regarding bone conduction. PMID:19841600

  8. Birth weight and adult bone metabolism are unrelated

    DEFF Research Database (Denmark)

    Frost, Morten; Petersen, Inge Lund; Andersen, Thomas Levin

    2013-01-01

    INTRODUCTION: Low birth weight (BW) has been associated with poor bone health in adulthood. The aim of this study was to investigate the association between BW and bone mass and metabolism in adult BW discordant monozygotic twins (MZ). METHODS: 153 BW extremely discordant MZ twin-pairs were...... recruited from the Danish Twin Registry. Serum vitamin D (25OHD) and bone turnover markers (BTM) P1NP, 1CTP, and CTX were quantified. Femoral neck, total hip, lumbar spine, and whole body bone mineral density (FN-BMD, TH-BMD, LS-BMD, and WB-BMD) were measured using DXA. Twins were studied as single...

  9. Eldecalcitol, a vitamin D analog, reduces bone turnover and increases trabecular and cortical bone mass, density, and strength in ovariectomized cynomolgus monkeys.

    Science.gov (United States)

    Smith, Susan Y; Doyle, Nancy; Boyer, Marilyne; Chouinard, Luc; Saito, Hitoshi

    2013-11-01

    Vitamin D insufficiency is common in elderly people worldwide, and intake of supplementary calcium and vitamin D is recommended to those with a high risk of fracture. Several clinical studies and meta-analyses have shown that calcium and vitamin D supplementation reduces osteoporotic fractures, and a strong correlation exists between vitamin D status and fracture risk. Vitamin D supplementations improve calcium balance in the body; however, it remains unclear whether vitamin D directly affects bone metabolism. Recently, eldecalcitol (ELD), an active form of vitamin D analog, has been approved for the treatment of osteoporosis in Japan. A 3-year clinical trial showed ELD treatment increased lumbar spine bone mineral density (BMD) and reduced fracture risk in patients with osteoporosis. To evaluate the mechanism of ELD action in bone remodeling, ovariectomized cynomolgus monkeys were treated with 0.1 or 0.3μg/day of ELD for 6months. This treatment increased lumbar BMD by 4.4% and 10.2%, respectively, and suppressed ovariectomy-induced increases in bone turnover markers compared to OVX-vehicle control. Histomorphometric analysis of bone revealed that both bone formation parameters and bone resorption parameters in the trabecular bone of the lumbar vertebrae were suppressed by ELD treatment. ELD treatment also improved biomechanical properties of the lumbar vertebrae and the femoral neck in the ovariectomized cynomolgus monkeys. These results indicate that, in a bone-remodeling animal model, ELD increases BMD and improves bone biomechanical properties by normalizing bone turnover. Therefore, ELD has a direct and potentially beneficial effect on bone metabolism. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Sex determination using discriminant analysis of upper and lower extremity bones: New approach using the volume and surface area of digital model.

    Science.gov (United States)

    Lee, U-Young; Kim, In-Beom; Kwak, Dai-Soon

    2015-08-01

    This study used 110 CT images taken from donated Korean cadavers to create 3-D models of the following upper and lower limb bones: the clavicle, scapula, humerus, radius, ulna, hip bone (os coxa), femur, patella (knee cap), tibia, talus, and calcaneus. In addition, the bone volume and surface area were calculated to determine sex differences using discriminant analysis. Significant sex differences were found in all bones with respect to volume and surface area (phip bone>tibia>humerus>scapula), although the order of surface area was different. The largest surface area in men was the femur and in women was the hip bone (psex determination (94%). When using the surface area of multiple bones, the maximum accuracy (99.4%) was achieved. The equation was as follows: (discriminant equation of surface area; femalesex determination.

  11. Bone mass and the CAG and GGN androgen receptor polymorphisms in young men.

    Directory of Open Access Journals (Sweden)

    Amelia Guadalupe-Grau

    Full Text Available BACKGROUND: To determine whether androgen receptor (AR CAG (polyglutamine and GGN (polyglycine polymorphisms influence bone mineral density (BMD, osteocalcin and free serum testosterone concentration in young men. METHODOLOGY/PRINCIPAL FINDINGS: Whole body, lumbar spine and femoral bone mineral content (BMC and BMD, Dual X-ray Absorptiometry (DXA, AR repeat polymorphisms (PCR, osteocalcin and free testosterone (ELISA were determined in 282 healthy men (28.6+/-7.6 years. Individuals were grouped as CAG short (CAG(S if harboring repeat lengths of 21, and GGN was considered short (GGN(S or long (GGN(L if GGN 23. There was an inverse association between logarithm of CAG and GGN length and Ward's Triangle BMC (r = -0.15 and -0.15, P<0.05, age and height adjusted. No associations between CAG or GGN repeat length and regional BMC or BMD were observed after adjusting for age. Whole body and regional BMC and BMD values were similar in men harboring CAG(S, CAG(L, GGN(S or GGN(L AR repeat polymorphisms. Men harboring the combination CAG(L+GGN(L had 6.3 and 4.4% higher lumbar spine BMC and BMD than men with the haplotype CAG(S+GGN(S (both P<0.05. Femoral neck BMD was 4.8% higher in the CAG(S+GGN(S compared with the CAG(L+GGN(S men (P<0.05. CAG(S, CAG(L, GGN(S, GGN(L men had similar osteocalcin concentration as well as the four CAG-GGN haplotypes studied. CONCLUSION: AR polymorphisms have an influence on BMC and BMD in healthy adult humans, which cannot be explained through effects in osteoblastic activity.

  12. Change in bone mass distribution induced by hormone replacement therapy and high-impact physical exercise in post-menopausal women.

    Science.gov (United States)

    Cheng, S; Sipilä, S; Taaffe, D R; Puolakka, J; Suominen, H

    2002-07-01

    The purpose of this intervention trial was to determine whether changes in bone mass distribution could be observed in postmenopausal women following hormone replacement therapy (HRT) and/or high-impact physical exercise. Eighty healthy women, aged 50-57 years, at menopause and with no previous use of HRT, were randomly assigned to one of four groups: HRT; exercise (Ex); HRT + Ex (ExHRT); and control (Co). HRT administration was conducted in a double-blind manner for 1 year using estradiol plus noretisterone acetate (Kliogest). The exercise groups participated in a 1 year progressive training program consisting of jumping and bounding activities. Subjects participated in two supervised sessions per week and were asked to perform a series of exercises at home 4 days/week. Bone measurements using a quantitative computed tomography scanner (Somatom DR, Siemens) were obtained from the proximal femur, midfemur, proximal tibia, and tibial shaft. Data were analyzed with a software program (BONALYSE 1.3) calculating density (g/cm(3)), cross-sectional area (CSA; mm(2)), and moments of inertia (I(max), I(min), I(polar)). In addition, the bone mass spectrum was determined as a function of the angular distribution around the bone mass center (polar distribution) and the distance from the bone mass center through the diaphyseal wall (radial distribution). After the 1 year period, there was an overall interaction of group x time in bone mineral density (BMD) at the proximal femur (p = 0.05) and tibial shaft (p = 0.035). Women in the ExHRT and HRT groups had increased proximal femur and tibial shaft BMD when compared with the change observed in the Co group (p = 0.024-0.011). The change was more pronounced in the cortical tibia, wherein the ExHRT group also differed from the Ex group (p = 0.038). No significant changes were found in bone CSA at any of the measured sites. The radial distribution indicated an increase of BMD in the endocortical part of the measured sites in the HRT

  13. Determination of bone mineral density of the distal extremity of the radio in Rottweiller, by radiographic optic densitometry;Determinacao da densidade mineral ossea da extremidade distal do radio de caes da raca Rottweiller, por meio da densitometria optica radiografica

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Jefferson Douglas Soares, E-mail: radiologia@unifeob.edu.b [Fundacao de Ensino Octavio Bastos (UNIFEOB), Sao Joao da Boa Vista, SP (Brazil). Fac. de Medicina e Veterinaria; Sterman, Franklin de Almeida [Universidade de Sao Paulo (USP), Butanta, SP (Brazil). Fac. de Medicina Veterinaria e Zootecnia. Dept. de Cirurgia

    2010-06-15

    This study allowed the standardization of the bone mineral density (BMD) of the distal extremity of the radio of 36 dogs adults in Rottweiler breed by radiographic optic densitometry. The limbs of the animals were radiographed with scale of aluminum that served as a reference. The radiographs images were digitalized and analyzed by a computer program for comparison of gray tones between the standard image and the image of the reference scale radiographed with the bone. Afterwards the values of density were expressed in millimeters of aluminum. Also studied the correlations between BMD and the sex, weight and external measures as the length of spine, height of the animal and circumference the distal extremity of the limb in study. The mean values and standard deviations of the bone mineral density of the distal extremity of the radio were: for the metaphyseal region the average of BMD of 7,88+-0,89 mmAl, the diaphyseal region 1 the average of BMD of 8,58+-0,80 mmAl and for diaphyseal region 2 of BMD of 9,00+-0,74 mmAl. (author)

  14. Determinants of Growth, Adiposity and Bone Mass in Early Life : The Generation R Study

    NARCIS (Netherlands)

    D.H.M. Heppe (Denise)

    2016-01-01

    markdownabstractAbstract Environmental influences during fetal life and early infancy have been suggested to influence body composition throughout the life-course. Especially poor fetal nutrition and fetal growth restriction have been designated important risk factors for gaining high fat mass or

  15. Polymorphisms of muscle genes are associated with bone mass and incident osteoporotic fractures in Caucasians

    DEFF Research Database (Denmark)

    Harsløf, Torben; Frost, M; Nielsen, T L

    2013-01-01

    ), and lean body mass. We analyzed two independent cohorts: the Danish Osteoporosis Prevention Study (DOPS), comprising 2,016 perimenopausal women treated with hormone therapy or not and followed for 10 years, and the Odense Androgen Study (OAS), a cross-sectional, population-based study on 783 men aged 20...

  16. Determinants of Growth, Adiposity and Bone Mass in Early Life : The Generation R Study

    NARCIS (Netherlands)

    D.H.M. Heppe (Denise)

    2016-01-01

    markdownabstractAbstract Environmental influences during fetal life and early infancy have been suggested to influence body composition throughout the life-course. Especially poor fetal nutrition and fetal growth restriction have been designated important risk factors for gaining high fat mass

  17. Variations of the Stellar Initial Mass Function in the Progenitors of Massive Early-type Galaxies and in Extreme Starburst Environments

    Science.gov (United States)

    Chabrier, Gilles; Hennebelle, Patrick; Charlot, Stéphane

    2014-12-01

    We examine variations of the stellar initial mass function (IMF) in extreme environments within the formalism derived by Hennebelle & Chabrier. We focus on conditions encountered in progenitors of massive early-type galaxies and starburst regions. We show that, when applying the concept of turbulent Jeans mass as the characteristic mass for fragmentation in a turbulent medium, the peak of the IMF in such environments is shifted toward smaller masses, leading to a bottom-heavy IMF, as suggested by various observations. In very dense and turbulent environments, we predict that the high-mass tail of the IMF can become even steeper than the standard Salpeter IMF, with a limit for the power-law exponent α ~= -2.7, in agreement with recent observational determinations. This steepening is a direct consequence of the high densities and Mach values in such regions but also of the time dependence of the fragmentation process, as incorporated in the Hennebelle-Chabrier theory. We provide analytical parameterizations of these IMFs in such environments to be used in galaxy evolution calculations. We also calculate the star-formation rates and the mass-to-light ratios expected under such extreme conditions and show that they agree well with the values inferred in starburst environments and massive high-redshift galaxies. This reinforces the paradigm of star formation as being a universal process, i.e., the direct outcome of gravitationally unstable fluctuations in a density field initially generated by large-scale, shock-dominated turbulence. This globally enables us to infer the variations of the stellar IMF and related properties for atypical galactic conditions.

  18. Variations of the stellar initial mass function in the progenitors of massive early-type galaxies and in extreme starburst environments

    Energy Technology Data Exchange (ETDEWEB)

    Chabrier, Gilles [Ecole Normale Supérieure de Lyon, CRAL, UMR CNRS 5574, F-69364 Lyon Cedex 07 (France); Hennebelle, Patrick [Laboratoire AIM, CEA/IRFU, F-91191 Gif-sur-Yvette Cedex (France); Charlot, Stéphane [UPMC-CNRS, UMR7095, Institut d' Astrophysique de Paris, F-75014 Paris (France)

    2014-12-01

    We examine variations of the stellar initial mass function (IMF) in extreme environments within the formalism derived by Hennebelle and Chabrier. We focus on conditions encountered in progenitors of massive early-type galaxies and starburst regions. We show that, when applying the concept of turbulent Jeans mass as the characteristic mass for fragmentation in a turbulent medium, the peak of the IMF in such environments is shifted toward smaller masses, leading to a bottom-heavy IMF, as suggested by various observations. In very dense and turbulent environments, we predict that the high-mass tail of the IMF can become even steeper than the standard Salpeter IMF, with a limit for the power-law exponent α ≅ –2.7, in agreement with recent observational determinations. This steepening is a direct consequence of the high densities and Mach values in such regions but also of the time dependence of the fragmentation process, as incorporated in the Hennebelle-Chabrier theory. We provide analytical parameterizations of these IMFs in such environments to be used in galaxy evolution calculations. We also calculate the star-formation rates and the mass-to-light ratios expected under such extreme conditions and show that they agree well with the values inferred in starburst environments and massive high-redshift galaxies. This reinforces the paradigm of star formation as being a universal process, i.e., the direct outcome of gravitationally unstable fluctuations in a density field initially generated by large-scale, shock-dominated turbulence. This globally enables us to infer the variations of the stellar IMF and related properties for atypical galactic conditions.

  19. Effect of estrogen on bone mass in different physiological period%不同生理时期雌激素对骨量的影响

    Institute of Scientific and Technical Information of China (English)

    范璐; 林华

    2011-01-01

    随着年龄增长,女性卵巢功能逐渐成熟、减弱、衰退,引起雌激素水平变化,导致骨量变化.特别是在青春期、孕产期、绝经期和老年期,雌激素水平会有较大变化.此时应特别关注女性的骨转换率和骨密度变化,防止骨密度下降甚至骨质疏松的发生.研究女性不同生理时期的骨量变化,有助于临床预防和治疗女性骨质疏松症,提高长期生活质量.%The mature, weakness, and senescence of the ovarian function in females with aging result in a change of estrogen level, and lead to a change of bone mass. Especially during the period of puberty,pregnancy, postmenopausal, and elderly, the level of estrogen alters a great deal. It is the time to pay more attention to the alteration of bone turnover and bone mass, and to prevent the decrease of bone mineral density and the occurrence of osteoporosis. The study of bone mass alteration during different physiological period in the female may facilitate the prevention and treatment of osteoporosis in females and improve the long term live quality.