bluuebunny/crossref_metadata_2025 huggingface dataset:
Stimulation of neonatal mouse calvarial bone resorption by the glucocorticoids hydrocortisone and dexamethasone
Authors: Conaway Herschel H. , Grigorie Daniel , Dr. Lerner Ulf H.
Published: February 2010

In vitro stimulation of bone resorption was observed with the glucocorticoids hydrocortisone and dexamethasone. Dosage-dependent release of 45Ca from neonatal mouse calvarial bones was found for both steroids, with half-maximal responses for hydrocortisone and dexamethasone of 0.3 and 0.08 μM, respectively. Significant release of stable calcium (Ca2+), inorganic phosphate (Pi), and the lysosomal enzyme β-N-acetylglucosaminidase was noted following treatment of mouse calvariae with either 1 μM hydrocortisone or 1 μM dexamethasone. Additionally, both 1 μM hydrocortisone and 1 μM dexamethasone elicited release of 3H from calvarial bones prelabeled with [3H]proline. The stimulation of bone resorption by the glucocorticoids, as assessed by 45Ca release, was sustained over 120 h of culture. Inhibition of 45Ca release from calvariae treated with either 1 μM hydrocortisone or 0.1 μM dexamethasone was observed with 0.01-30 nM salmon calcitonin (sCT), 0.1 mM acetazolamide, and 0.1 mM of the bisphosphonate AHPrBP. Inhibition of glucocorticoid-induced bone resorption by sCT occurred without “escape from calcitonin-induced inhibition.” The 45Ca release stimulated by 1 μM hydrocortisone and 0.1 μM dexamethasone was also inhibited by 10 μM progesterone in a competitive manner and by 1 μM of the antiglucocorticoid RU38486, both of which are modulators of glucocorticoid binding. Prostaglandin E2 (PGE2) formation by 10 nM parathyroid hormone (PTH) in neonatal mouse calvarial bones was inhibited by both 1 μM hydrocortisone and 1 μM dexamethasone, but neither compound altered basal PGE2 formation. Exposure of calvarial bones to the mitotic inhibitors hydroxyurea and mitomycin C inhibited 45Ca release stimulated by 1 μM hydrocortisone and 1 μM dexamethasone. In contrast, addition of 1 ng/ml of recombinant murine granulocyte macrophage colony stimulating factor (rmGM-CSF) had no effect on 45Ca release elicited by the glucocorticoids. These results suggest that hydrocortisone and dexamethasone stimulate osteoclastic resorption in neonatal mouse calvariae by a receptor-mediated mechanism that is dependent on cellular replication.
Creatine kinase brain isoenzyme (BB-CK) presence in serum distinguishes osteopetroses among the sclerosing bone disorders
Authors: Whyte Michael P. , Chines Arkadi , Silva David P. , Landt Yvonne , Ladenson Jack H.
Published: February 2010

Creatine kinase (CK) isoenzyme BB-CK is predominantly found in brain and is not normally detected in the blood. A few recent reports, however, have described BB-CK in serum from several patients with osteopetrosis (OP). To evaluate the presence and specificity of BB-CK in serum in the osteopetroses among disorders that increase skeletal mass, we quantitated total CK activity and CK isoenzymes in 15 patients representing the five major clinical forms of OP (2 infantile, 3 intermediate, 7 adult [2 type I, 5 type II], and 3 carbonic anhydrase II [CA II] deficiency cases) and in 22 patients representing 14 other types of sclerosing bone disease. All OP patients (except the two adult type I subjects) had BB-CK readily detected in their serum. Conversely, only 1 of the 22 patients with other sclerosing bone disorders had detectable BB-CK in serum (1 of 3 patients with fibrodysplasia [myositis] ossificans progressiva who had barely measurable activity). In three OP patients (one of two with the infantile form and two of five with adult, type II disease), BB-CK values were sufficiently high that serum total CK activity was elevated. In a newborn with malignant OP, both cord blood plasma and peripheral blood serum had substantial amounts of BB-CK. In three subjects (with adult type II OP), who were restudied 2-6 years later, BB-CK was still elevated in their blood. BB-CK in serum appears to distinguish the osteopetroses among the sclerosing bone disorders. Absence of serum BB-CK in adult type I disease suggests that this condition may not be a genuine form of OP. Assay of BB-CK in fetal blood could be studied as a means for prenatal diagnosis of malignant OP. Why the osteoclast failure that characterizes all true forms of OP is associated with BB-CK in the circulation is a new question for skeletal biologists.
Human osteoclastoma-derived stromal cells: Correlation of the ability to form mineralized nodules in vitro with formation of bone in vivo
Authors: James Ian E. , Dodds Robert A. , Olivera Diane L. , Nuttall Mark E. , Gowen Maxine
Published: February 2010

It has been suggested that the stromal element of human osteoclastomas contains osteoblastic cells. In this study, we demonstrate that osteoclast-depleted, passaged stromal cells express alkaline phosphatase and osteocalcin in vitro and form mineralized nodules under appropriate culture conditions. In addition, we describe a model in which severe combined immunodeficient (SCID) mice were used to support the differentiation of these putative human osteoblast progenitors in vivo. Lesions formed from human stromal cells were identified using the OKa blood group antigen and human procollagen type I antibodies. By 21 days, the lesion was a complete bone unit: a fully mineralized cortex, remodeling trabeculae, and a highly cellular marrow space. Stromal cells derived from six out of seven osteoclastomas produced identical lesions. Further studies have demonstrated that the capacity of the osteoclastoma-derived stromal cells to form bone in vivo and in vitro is passage dependent; early passages were osteogenic in both model systems, while later passages were not. In conclusion, we have developed a model in which the osteogenic nature of cells can be confirmed in vivo. Furthermore, human osteoclastoma-derived stromal cells provide a source of these osteogenic cells to study human osteoblast differentiation, both in vivo and in vitro.
Bisphosphonates induce apoptosis in mouse macrophage-like cells in vitro by a nitric oxide-independent mechanism
Authors: Dr. Rogers Michael J. , Chilton Kattya M. , Coxon Fraser P. , Lawry John , Smith M. Olivia , Suri Sunita , Russel R. Graham G.
Published: February 2010

Bisphosphonates (BPs) are an important class of antiresorptive drugs used in the treatment of bone diseases, including osteoporosis. Although their mechanism of action has not been identified at the molecular level, there is substantial evidence that BPs can have a direct effect on osteoclasts by mechanisms that may lead to osteoclast cell death by apoptosis. BPs can also inhibit proliferation and cause cell death in macrophages in vitro. We have now shown that the toxic effect of BPs on macrophages is also due to the induction of apoptotic, rather than necrotic, cell death. Morphological and biochemical features that are definitive of apoptosis (chromatin condensation, nuclear fragmentation, and endonuclease-mediated internucleosomal cleavage of DNA) could be identified in mouse macrophage-like J774 and RAW264 cells, following treatment with 100 μM Pamidronate, alendronate, and ibandronate for 24 h or more. Clodronate was much less potent, even at 2000 μM, while 2000 μM etidronate did not cause apoptosis. Apoptosis was not due to increased synthesis of nitric oxide and could not be prevented by inhibitors of nitric oxide synthases. Since macrophages, like osteoclasts, are particularly susceptible to BPs, these observations support the recent suggestion that the mechanism by which BPs inhibit bone resorption may involve osteoclast apoptosis. Furthermore, the macrophage-like cell lines used in this study may be a convenient model with which to identify the molecular mechanisms by which BPs promote apoptosis in osteoclasts. Induction of macrophage apoptosis by BPs in vivo may also account, at least in part, for the anti-inflammatory properties of BPs as well as the ability of BPs to cause an acute phase response.
Evaluation of periprosthetic bone using dual-energy X-ray absorptiometry: Precision of the method and effect of operation on bone mineral density
Authors: Kröger Heikki , Miettinen Hannu , Arnala Ilkka , Koski Eila , Rushton Neil , Suomalainen Olavi
Published: February 2010

To assess the perioperative bone loss of femur during total hip arthroplasty (THA), periprosthetic bone mineral density (BMD) of the seven regions of interests (Gruen zones) was determined with dual-energy x-ray absorptiometry (DXA) preoperatively in both proximal femurs and postoperatively in the involved side in 53 patients with degenerative hip osteoarthrosis. The mean (standard deviation, SD) precision error (coefficient of variation percent, CV%) in various regions of interest (ROIs) based on two consecutive measurements (n = 16) were 2.3 (0.8)%, 2.5 (1.5)%, and 2.8 (1.6)% for uncemented stems, cemented stems, and control sides, respectively. Furthermore, the mean variability caused by the rotation of femur was 3.5 (1.4)%. The most significant perioperative bone loss (13.5-19.2%) was found in the calcar area (zone 7) after noncemented THA. Zone 4, representing the bone below the prosthesis, also showed BMD decreases. These decreases suggest perioperative bone loss owing to rasping and reaming the calcar and bone canal. However, after cemented THA, highly significant BMD increases were found in all the lateral zones. The calcar area was the only site where significant perioperative bone loss was detected (12.8%). In conclusion, DXA is a precise method for quantifying bone mass and density changes in the follow-up of THA. However, when interpreting the results, the preoperative BMD, differences between the femurs and the effect of operation on bone mass should be taken into account. We suggest that the best reference for BMD follow-up is the periprosthetic BMD of the involved side measured soon after the THA.
Markers of bone resorption predict hip fracture in elderly women: The EPIDOS prospective study
Authors: Garnero P. , Hausherr E. , Chapuy M.-C. , Marcelli C. , Grandjean H. , Muller C. , Cormier C. , Bréart G. , Meunier P.J. , Dr. Delmas Pierre D.
Published: February 2010

Increased bone turnover has been suggested as a potential risk factor for osteoporotic fractures. We investigated this hypothesis in a prospective cohort study performed on 7598 healthy women more than 75 years of age. One hundred and twenty-six women (mean years 82.5) who sustained a hip fracture during a mean 22-month follow-up were age-matched with three controls who did not fracture. Baseline samples were collected prior to fracture for the measurement of two markers of bone formation and three urinary markers of bone resorption: type I collagen cross-linked N- (NTX) or C-telopeptide (CTX) and free deoxypyridinoline (free D-Pyr). Elderly women had increased bone formation and resorption compared with healthy premenopausal women. Urinary excretion of CTX and free D-Pyr, but not other markers, was higher in patients with hip fracture than in age-matched controls (p = 0.02 and 0.005, respectively). CTX and free D-Pyr excretion above the upper limit of the premenopausal range was associated with an increased hip fracture risk with an odds ratio (95% confidence interval) of 2.2 (1.3-3.6) and 1.9 (1.1-3.2), respectively, while markers of formation were not. Increased bone resorption predicted hip fracture independently of bone mass, i.e., after adjustment for femoral neck bone mineral density (BMD) and independently of mobility status assessed by the gait speed. Women with both a femoral BMD value of 2.5 SD or more below the mean of young adults and either high CTX or high free D-Pyr levels were at greater risk of hip fracture, with an odds ratio of 4.8 and 4.1, respectively, than those with only low BMD or high bone resorption. Elderly women are characterized by increased bone turnover, and some markers of bone resorption predict the subsequent risk of hip fracture independently of hip BMD. Combining the measurement of BMD and bone resorption may be useful to improve the assessment of the risk of hip fracture in elderly women.
Differences in bone mineral in young Asian and Caucasian Americans may reflect differences in bone size
Authors: Bhudhikanok Grace S. , Wang May-Choo , Eckert Kathyrn , Matkin Chantal , Marcus Robert , Dr. Bachrach Laura K.
Published: February 2010

Bone mineral content (BMC) and areal bone mineral density (BMD) have been reported to be lower in Asian than in Caucasian adults. To determine if racial differences in bone mass are present in younger subjects and whether they reflect differences in estimated volumetric bone density or in bone size, we compared measurements of bone mineral in healthy young Asian- and Caucasian-American males and females. Bone mineral was measured at the lumbar spine (L2-L4), femoral neck (FN), and whole body (WB) by dual-energy X-ray absorptiometry (DXA) in 99 Asians (49 females, 50 males) and 103 Caucasians (54 females, 49 males) ages 9-26 years. Results were expressed as BMC, BMD, and apparent density (BMAD), an estimate of volumetric bone density that reduces the effect of bone size. Subjects were compared on the basis of chronological age as well as by Tanner stage to correct for potential differences in the timing of puberty. Habitual dietary intake and physical activity were also assessed and correlated with bone mineral. The Asian and Caucasian cohorts differed in body size, diet, and physical activity. Asian females were shorter than the Caucasian females at all stages of puberty and weighed less at pre-/early puberty (p < 0.05). Asian males were older than Caucasians at midpuberty (p < 0.01) and weighed less than the Caucasian males at pubertal maturity (p = 0.001). Asian youths also consumed less calcium and reported less weight-bearing activity. Racial differences were most apparent when comparing BMC data. Asian males had greater spine BMC at midpuberty and lower WB BMC at maturity (p < 0.05). Asian females had lower FN BMC through midpuberty and lower WB BMC in pre-/early puberty (p < 0.05). WB BMD and WB BMC/height values were significantly lower in mature Asian versus Caucasian males. No significant racial differences in BMAD were observed. Multivariate regression analysis indicated that the differences in BMD and BMAD between Asian and Caucasian subjects were largely attributable to differences in weight and pubertal stage, and, at the FN, in weight-bearing activity. Further, the explanatory variables were less strongly associated with BMAD than with BMD. In summary, no significant differences in BMD were found between Asian and Caucasian youths through midpuberty; however, WB BMD and WB BMC/height values were lower in Asian males at sexual maturity. We conclude that observed differences in bone mineral between Asians and Caucasians may be partially attributed to the smaller bone size of Asians.
Determinants of premenopausal bone mineral density: The interplay of genetic and lifestyle factors
Authors: Salamone Loran M. , Glynn Nancy W. , Black Dennis M. , Ferrell Robert E. , Palermo Lisa , Epstein Robert S. , Kuller Lewis H. , Cauley Jane A.
Published: February 2010

Bone mineral density (BMD) is a reflection of both genetic and lifestyle factors. The interplay of genetic (vitamin D receptor [VDR] gene polymorphisms) and lifestyle factors on BMD at the lumbar spine and proximal femur was examined in 470 healthy premenopausal women, aged 44–50 years, using a Hologic QDR 2000 densitometer. The objective of this study was to examine the genetic and lifestyle determinants of premenopausal BMD. Each participant was genotyped for BsmI polymorphism at the VDR gene locus. The presence of a restriction site within VDR, specified as bb (189, 40.2%) (n, %) was associated with reduced spinal BMD, whereas absence of this site in BB (97, 20.6%) conferred greater spinal BMD, as did the genotype Bb (184, 39.1%). Associations between smoking, alcohol use, oral contraceptives, education level, multivitamins, number of children, degree of obesity, body weight, physical activity, dietary calcium intake, and VDR genotype to BMDs were examined. VDR genotype, body weight, degree of obesity, physical activity, and dietary calcium intake were all significant determinants of BMD. The association of VDR genotype with BMD at the femoral neck appeared to be modified by calcium intake (BB and Bb: 0.797 ± 0.11 g/cm2 vs. 0.844 ± 0.11 g/cm2, interaction term, p = 0.06) for low (<1036 mg/day) and high (⩾1036 mg/day; upper quartile) calcium intakes, respectively. A similar trend was demonstrated for physical activity. These findings suggest that prophylactic interventions aimed at achieving and maintaining optimal BMD, such as greater calcium intake or physical activity, may be important in maximizing one's genetic potential for BMD.
Retired elite female ballet dancers and nonathletic controls have similar bone mineral density at weightbearing sites
Authors: Khan Karim M. , Green Robyn M. , Saul Andrew , Bennell Kim L. , Crichton Kenneth J. , Hopper John L. , Wark John D.
Published: February 2010

Elite female ballet dancers exhibit several risk factors for osteoporosis during their performing years. To study the long-term effect of this lifestyle, we compared the bone mineral density (BMD) of 101 retired elite female ballet dancers (mean age 51 years, SD = 14 years) and 101 normal controls, derived from a twin study, matched hierarchically for age, height, weight, and menopausal status. The dancers, who had been retired for a mean of 25.6 years (range 1–53 years) reported a greater prevalence of previous menstrual disturbance, greater lifetime alcohol intake and smoking, and a lower dietary milk intake in adolescence than controls (all p < 0.05). However, current exercise in the dancers was twice that of the controls (p < 0.01). The BMD of retired dancers did not differ from that of the controls at weightbearing sites. The mean ± SE difference in BMD (dancers minus controls) was 0.009 ± 0.013 at the total body, –0.009 ± 0.018 at the total hip, 0.005 ± 0.017 at the femoral neck, 0.014 ± 0.018 at the femoral trochanter, 0.036 ± 0.022 at the femoral intertrochanter and –0.017 ± 0.021 at the lumbar spine. Retired dancers had lower mean (± SE) BMD at the nonweightbearing sites: ultradistal radius (–0.029 ± 0.008) (p < 0.01) and at the midthird radius (–0.019 ± 0.011) (p < 0.05). There was no difference in the proportion in each of the World Health Organization (WHO) categories of osteopenia (t score –1.0 to –2.5) and osteoporosis (t score <–2.5) at any of the measured sites. Regression analysis revealed that menstrual disturbance was negatively associated with BMD at the lumbar spine and the ultradistal radial sites, but not at the weightbearing femoral sites. This sample of retired elite ballet dancers who had multiple historical risk factors does not appear to have an increased risk for future hip or vertebral fracture based on WHO standards.
Detection of measles virus nucleocapsid transcripts in circulating blood cells from patients with paget disease
Authors: Reddy Sakamuri V. , Singer Frederick R. , Mallette Lawrence , Roodman G. David
Published: February 2010

Paget disease of bone is characterized by abnormalities in all phases of bone remodeling, but the fundamental cellular abnormality resides in the osteoclast (OCL). Osteoclasts in bone involved by Paget disease contain viral-like nuclear and cytoplasmic inclusions that react with antibodies directed against paramyxovirus nucleocapsid proteins, such as measles virus, respiratory syncytial virus, or canine distemper virus. However, the identity of the virus or the mechanisms responsible for its persistence or pathologic role in Paget disease is unclear. Furthermore, although Paget disease persists for many years, it remains a highly localized process with new lesions rarely if ever developing in previously unaffected bones. Since osteoclasts are formed by fusion of mononuclear precursors derived from colony forming unit-granulocyte macrophage (CFU-GM), the granulocyte-macrophage progenitor, we used reverse transcriptase polymerase chain reaction (RT-PCR) analysis to determine if CFU-GM, more differentiated osteoclast precursors, and peripheral blood cells derived from CFU-GM express measles virus nucleocapsid (MV-N) transcripts. We found that osteoclast precursors, as well as peripheral blood mononuclear cells, express MV transcripts in 9 of 13 patients. Sequence analysis of the PCR amplified products confirmed nucleotide identity of MV-N transcripts expressed in peripheral blood and bone marrow-derived cells from the same patient. In contrast, MV-N transcripts were not detected in OCL precursors or the peripheral blood from 10 normal subjects. In situ hybridization studies using 35S-labeled antisense riboprobes to MV-N transcripts further confirmed the expression of MV transcripts in these cells. Sequence analysis of the PCR amplified product from one of these patients also identified a novel mutation that converted lysine441 to glutamic acid441 in the MV-N transcript. These data demonstrate that OCL precursors and circulating peripheral blood cells also express MV transcripts in patients with Paget disease and suggest that the pagetic marrow microenvironment plays a critical role in maintaining the highly localized nature of the lesions in Paget disease. (J Bone Miner Res 1996;11:1602–1607)
Transforming growth factor-β stimulates bone resorption in neonatal mouse calvariae by a prostaglandin-unrelated but cell proliferation-dependent pathway
Authors: Dr. Lerner Ulf H.
Published: February 2010

The relationships between bone resorption, prostanoid formation, and cell proliferation in cultured neonatal mouse calvariae stimulated with transforming growth factor-β (TGF-β) have been examined. Bone resorption was assessed by analyzing the mobilization of minerals (45Ca, Ca2+, Pi) and the release of 3H from bones prelabeled with [3H] proline. Prostanoid formation was determined by analyzing the amounts of prostaglandin E2 (PGE2) and 6-keto-prostaglandin F1α (the stable breakdown product of PGI2) in culture media. Purified porcine TGF-β1 and recombinant human TGF-β2 stimulated the release of 45Ca and the formation of prostanoids. The effects were time and dose dependent. The concentrations of TGF-β1 and TGF-β2 causing half maximal stimulation of 45Ca release were 1 and 0.1 ng/ml, respectively. TGF-β1 also enhanced the release of 3H from [3H]proline labeled bones and the mobilization of Ca2+ and Pi from unlabeled bones, as well as the release of lysosomal enzymes (β-N-acetylglu-cosaminidase). The degree of stimulation of mineral mobilization and matrix degradation was less than that obtained in bones stimulated with parathyroid hormone or 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). TGF-β1-induced stimulation of 45Ca release was inhibited by calcitonin, acetazolamide, and the bisphosphonate AHPrBP, three different osteoclast inhibitors. In contrast to the escape from calcitonin-induced inhibition seen in parathyroid hormone (PTH)-stimulated bones, the inhibitory effect of calcitonin in TGF-β1-stimulated bones persisted in long-term cultures (144 h). The stimulatory effect of TGF-β1 was inhibited by anti-TGF-β1 and by γ-interferon (1000 U/ml). Indometacin (1 μM), flurbiprofen (1 μM), and meclofenamic acid (1 μM) completely abolished the stimulatory effect of TGF-β1 on PGE2 and 6-keto-PGF1α formation without affecting TGF-β1-induced stimulation of 45Ca release. Similarly, the stimulatory effect of TGF-β2 on 45Ca release was unaffected by indomethacin. In bones in which prostaglandin formation was abolished by indomethacin, a 45Ca release response to TGF-β1 was obtained at 12 h. The mitotic inhibitor hydroxyurea inhibited TGF-β1 but not PTH-induced 45Ca release. These data demonstrate that TGF-β1 and TGF-β2 have the capacity to stimulate bone resorption and prostanoid formation in neonatal mouse calvariae, but that the effect of TGF-β on bone resorption is unrelated to prostanoid formation. In addition, it is shown that bone resorption stimulated by TGF-β is dependent on cell replication. (J Bone Miner Res 1996;11:1628-1639)
Na+/Ca2+ exchange in rat osteoblast-like UMR 106 cells
Authors: White Kenneth E. , Gesek Frank A. , Friedman Peter A.
Published: February 2010

Ca2+ efflux from osteoblasts is thought to be mediated by Na+/Ca2+ exchange and by a plasma membrane Ca2+-ATPase. The presence of plasma membrane Na+/Ca2+ exchange was determined in rat UMR 106 osteosarcoma cells by functional and molecular studies. Na+/Ca2+ exchange activity was tested by measuring changes of [Ca2+]i in single cells. After Na+ loading the cells and removing extracellular Na+, the direction of exchange was reversed and [Ca2+]i increased by 100%. Multiple isoforms of the NCX1 gene product, encoding plasma membrane Na+/Ca2+ exchangers, were cloned from UMR 106 cells and a sample of primary human osteoblasts using homology-based RT-PCR. Isoforms NACA3, NACA7, and NACA10 were found in UMR 106 cells, whereas human osteoblasts expressed NACA3 and NACA7. Transcripts for NCX2 and the Na+/Ca2+, K+ exchanger were not detected. Northern analysis of UMR 106 cells with a probe to the NCX1 gene product revealed the presence of a transcript of 7 kb, the size of the exchanger message. Western analysis of UMR 106 cell membrane preparations with a polyclonal antibody specific for the NCX1 exchanger showed the presence of reacting proteins consistent with the reported masses of the exchanger at 125 and 85 kD. These results demonstrate Na+-dependent Ca2+ efflux from UMR 106 cells and the presence of several NACA isoforms in UMR 106 and primary human osteoblasts. (J Bone Miner Res 1996;11:1666-1675)
Characteristics of NaF-induced differentiation of HL-60 cells
Authors: Kawase Tomoyuki , Oguro Akira , Orikasa Michiaki , Burns Douglas M.
Published: February 2010

Sodium fluoride (NaF) is known to stimulate osteoblastic bone formation, but little attention has been given to the possibility that NaF also affects bone resorption and the differentiation of osteoclastic progenitor cells. When human promyelocytic HL-60 cells were treated with NaF (0.5 mM, 0–4 days), cell proliferation was inhibited, and the addition of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) (10 nM, 0–4 days) augmented this antiproliferative effect. NaF increased cellular reduction of nitroblue tetrazolium (NBT), and this effect was strongly augmented by 1,25(OH)2D3. In addition, NaF produced marked changes in cellular morphology, increased cellular adhesion to plastic, reduced the nuclear/cytoplasmic ratio, and increased cellular expression of chloroacetate esterase, but failed to alter cellular nonspecific esterase activity. Furthermore, NaF increased expression of CD11b and CD66b, and this stimulation was enhanced by adding 1,25(OH)2D3. The sum of these changes in classical promyelocytic cellular indices suggest: (1) that NaF stimulates the early stages of HL-60 differentiation toward a granulocyte-like cell and (2) that 1,25(OH)2D3 promotes these actions of NaF. Additional experiments aimed at further understanding the NaF-induced conversion of HL-60 cells identified further changes. NaF also increased cellular production of prostaglandin E2 (PGE2) and nitric oxide (NO) and induced expression of inducible nitric oxide synthase (iNOS); 1,25(OH)2D3 once again augmented these NaF-induced effects. Similarly, NaF stimulated the production of interleukin 1α (IL-1α), IL-6, and tumor necrosis factor-α, and 1,25(OH)2D3 again strongly enhanced these effects. Indomethacin completely blocked stimulation of NBT reduction, NO production, and iNOS expression induced by NaF plus 1,25(OH)2D3; adding exogenous PGE2 (0.1-10 ng/ml) to these indomethacin-blocked cultures dose-dependently restored NO production. These additional findings together with the observed slow onset (24-48 h) of NaF and 1,25(OH)2D3 interaction strongly suggest that 1,25(OH)2D3 acts as a cofactor with NaF primarily through interaction with an endogenous NaF-induced cyclo-oxygenase product(s), quite possibly PGE2 itself. Such a mechanism for NaF and 1,25(OH)2D3 interaction would be strongly analogous to the interaction we have recently demonstrated between 1,25(OH)2D3 and PGE1 on the differentiation of HL-60 cells. (J Bone Miner Res 1996;11:1676-1687)
Inducible cyclo-oxygenase (COX-2) mediates the induction of bone formation by mechanical loading in vivo
Authors: Forwood M. R.
Published: February 2010

In vivo, indomethacin blockade of bone formation has been used to illustrate the role of prostaglandins. Indomethacin blocks the constitutive (COX-1) and inducible (COX-2) forms of cyclo-oxygenase, and is therefore nonspecific in its action. To test the hypothesis that COX-2 mediates the bone formation response to loading, rats were treated with vehicle, NS-398 (a specific COX-2 inhibitor) or indomethacin at 0.02, 0.2, or 2.0 mg/kg p.o. 3 h before loading the right tibia in four-point bending. Bending or sham loads of 65 N were applied for one bout of 300 cycles and bone formation assessed 5–8 days after loading. Mechanically induced bone formation at the endocortical surface was calculated by subtracting formation indices of the left leg (control) from those of the right (loaded), and woven bone surface and area were measured at the periosteal surface. Endocortical bone formation was significantly increased by bending but not sham loading (p < 0.05). The increase in the endocortical bone formation rate and mineralizing surface caused by bending was only partially inhibited by indomethacin, even at the highest dose, whereas NS-398 completely blocked bone formation at all doses (p < 0.05). The mineral apposition rate was depressed in a dose-response fashion by NS-398 (p < 0.05), but not by indomethacin. Woven bone formation at the periosteal surface was not prevented by treatment with indomethacin nor NS-398, suggesting that its formation is not dependent on prostaglandin production. These data suggest that induction of COX-2 is important for lamellar bone formation elicited by mechanical strain. (J Bone Miner Res 1996;11:1688-1693)
Demineralized bone matrix mediates differentiation of bone marrow stromal cells in vitro: Effect of age of cell donor
Authors: José Becerra , Andrades José A. , Ertl Delia C. , Sorgente Nino , Nimni Marcel E.
Published: February 2010

Bone maintenance requires a continuous source of osteoblasts throughout life. Its remodeling and regeneration during fracture repair is ensured by osteoprogenitor stem cells which are part of the stroma of the bone marrow (BM). Many investigators have reported that in cultured BM stromal cells there is a cell population that will differentiate along an osteogenic lineage if stimulated by the addition of osteogenic inducers, such as dexamethasone (dex), beta-glycerophosphate (β-GP), transforming growth factor beta-1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2). Here we report the effects of demineralized bone matrix (DBM) on the osteogenic differentiation of BM stromal cells in vitro, using morphological criteria, alkaline phosphatase (AP) activity, and calcium accumulation. DBM and DBM-conditioned medium (DBMcm) enhanced bone formation in the presence of dex and β-GP, whereas DBM particles caused changes in the cell phenotype. Temporal expression of total and skeletal AP by BM stromal cells from 4-week-old rats showed a biphasic pattern enhanced by DBM and suggesting the presence of two cell populations. In one population, AP synthesis reaches a maximum during the first week in culture, following which cells either die or loose their ability to synthesize AP. A second, less abundant population begins to proliferate and synthesize AP during the second and third weeks. The synthesis of AP, which often decreases by the third week, can be maintained at high levels only if DBM is added to the cultures. BM stromal cells isolated from 24- and 48-week-old rats showed a decrease or loss of this biphasic AP expression pattern compared with cells isolated from 4-week-old rats. The addition of DBM to cultures derived from 24- and 48-week-old rats stimulated mostly the second cell population to synthesize AP, suggesting that DBM contains a factor(s) that acts on a specific bone marrow cell population by increasing the proliferation of active cells or inducing the differentiation of dormant cells. (J Bone Miner Res 1996;11:1703-1714)
Effects of recombinant human growth hormone and insulin-like growth factor-I, with or without 17β-estradiol, on bone and mineral homeostasis of aged ovariectomized rats
Authors: Verhaeghe J. , van Bree R. , van Herck E. , Thomas H. , Skottner A. , Dequeker J. , Mosekilde L. I. , Einhorn T. A. , Bouillon R.
Published: February 2010

This study aimed to evaluate whether recombinant human growth hormone (rhGH) or insulin-like growth factor-I (rhIGF-I) can reverse or prevent further bone loss in aged osteopenic ovariectomized (OVX) rats and to compare their effects with those of 17β-estradiol (E2). Twelve-month-old rats were OVX, remained untreated for 8 weeks, and subsequently received daily subcutaneous (SC) injections of rhGH (75 μ/day), rhIGF-I (250 μg/day), E2 (1.5 μg/day), and their respective combinations during 8 weeks, and were then compared with sham-operated, pretreatment OVX, and saline-treated OVX rats. A single sc injection of rhGH resulted in peak hGH concentrations after 90 minutes, with a half-life of 124 minutes; the highest plasma IGF-I concentrations were reached 45 minutes after rhIGF-I injection (+57% vs. baseline) with a gradual decline thereafter. Measurements included: biochemical parameters of bone remodeling (plasma osteocalcin and urinary pyridinolines); histomorphometry of proximal tibial metaphysis; DXA of femur; biomechanical analysis of femur and fifth lumbar vertebra (L5); plasma 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), and calbindin-D9K in duodenal mucosa. Whereas all E2-treated OVX rats had much suppressed bone remodeling, rhGH or rhIGF-I had no effect on any biochemical or histomorphometrical parameter of remodeling. The bone mineral density (BMD) at the distal femoral metaphysis as well as parameters of strength at L5 were maintained at pretreatment values in OVX rats treated with E2, GH, or IGF-I, but not in saline-treated OVX rats; their effects were not additive, however. Trabecular bone volume in the tibial metaphysis was also higher in rats treated with these agents than in saline-treated rats, but this was more apparent at the primary than at the secondary spongiosa, suggesting that their mechanism of action is on primary spongiosa formation or breakdown. E2 alone was ineffective to augment the BMD at the femoral diaphysis; however, the diaphyseal BMD was 12–14% higher (p < 0.01) after 8 weeks of GH treatment than in pretreatment or saline-treated OVX rats and sham-operated rats, while IGF-I was less effective than GH. GH or IGF-I treatment had no effect on plasma 1,25(OH)2D3 or duodenal calbindin-D9K concentrations, but the combination of GH or IGF-I with E2 potentiated the effect of E2 to stimulate calbindin-D9K concentrations and urinary calcium excretion, indicating “hyperabsorption hypercalciuria”. In conclusion, the administration of rhGH and rhIGF-I, like that of E2, into aged OVX rats prevents further loss of bone mass and strength at sites containing trabecular bone. In addition, rhGH increases cortical bone mass above pretreatment values. (J Bone Miner Res 1996;11:1723-1735)
The effect of androgen treatment on bone metabolism in female-to-male transsexuals
Authors: Lips Paul , van Kesteren Paul J. M. , Asscheman Henk , Gooren Louis J. G.
Published: February 2010

Histomorphometry was performed in iliac crest biopsies from 15 female-to-male (F-M) transsexuals with a mean age of 30 ± 6.1 (SD) years. At the time of study, they had been treated with parenteral testosterone esters (250 mg/2 weeks) or oral testosterone undecanoate (160 mg/day). The median androgen treatment duration was 39 months. The patients had undergone hysterectomy and bilateral ovariectomy. The bone biopsy was obtained after double tetracycline labeling. Histomorphometric results were compared with data from 8 postmenopausal women and with data from 11 healthy men who had died suddenly. Dynamic parameters were compared with data from the literature. The biochemical picture was characterized by serum testosterone concentrations lower than in eugo-nadal men and estradiol concentrations lower than in eugonadal women and elevated gonadotrophin levels. The bone mineral density in the F-M transsexuals was as expected for age (Z-score −0.31 ± 1.49). Cortical thickness was significantly higher in F-M transsexuals than in both control groups. Trabecular bone structure was similar in F-M transsexuals and both control groups. The bone formation parameters were generally lower in F-M transsexuals than in the control groups. The eroded surface was lower in F-M transsexuals than in postmenopausal women. The low bone turnover and preservation of trabecular bone is consistent with the assumption that testosterone treatment protects the bone in these F-M transsexuals from the deleterious effects of estrogen deficiency. The increased cortical thickness suggests an anabolic effect of the testosterone treatment. (J Bone Miner Res 1996;11:1769–1773)
Serum N-terminal osteocalcin is a good indicator for estimating responders to hormone replacement therapy in postmenopausal women
Authors: Chen Jui-Tung , Hosoda Kenji , Hasumi Katsuhiko , Ogata Etsuro , Shiraki Masataka
Published: February 2010

To estimate the response to hormone replacement therapy (HRT) by bone metabolic markers, 36 patients with postmenopausal osteoporosis or osteopenia were studied to assess the correlation between percent baseline changes in lumbar bone mineral density (BMD) after 12 months and those in various bone metabolic markers after 3, 6, and 12 months of HRT. All the patients were treated with 0.625 mg of conjugated estrogen and 2.5 mg of medroxyprogesterone per day and continued for 12 months. BMD was significantly increased up to 4.19 ± 0.87% after 6 months and 4.93 ± 1.27% after 12 months of HRT (p = 0.0001 by analysis of variance). In accordance with this, changes in the levels of osteocalcin (p = 0.041), alkaline phosphatase (p = 0.0001), N-terminal osteocalcin (p = 0.0001), urinary excretion of pyridinoline/Cr (p = 0.0001), and deoxypyridinoline/Cr (p = 0.0001) were significantly decreased, respectively. Among these bone metabolic markers, only the change in the serum N-terminal osteocalcin at 3 months (r = 0.557, p = 0.0022), at 6 months (r = 0.470, p = 0.0184), and at 12 months (r = 0.545, p = 0.0061) significantly correlated with the change in BMD 12 months after HRT. The elution profiles of immunoreactive osteocalcin-related molecules in serum fractionated by reverse-phase high performance liquid chromatography revealed that the N-terminal fragment as well as the intact osteocalcin molecule decreased after 3 months of HRT. These results demonstrate that N-terminal osteocalcin is a suitable predictor for estimating good responders to HRT in postmenopausal women. (J Bone Miner Res 1996;11:1784–1792)
The hepatocytes of the brown trout (Salmo trutta fario): A stereological study of some cytoplasmic components with the breeding cycle
Authors: Rocha Eduardo , Rocha Maria J. , Lobo‐Da‐Cunha Alexandre , Galante Maria H. , Monteiro Rogério A.F.
Published: February 2010

Sex differences exist in fish hepatocytes, but studies for characterizing their cytology throughout the breeding cycle are still scarce; suggesting changes, but most lacking quantitative data. To address this limitation, to complement baseline data generated from the brown trout model, and to prove that sex‐specific seasonal changes exist, we made an unbiased stereological evaluation of the hepatocytic cytoplasm. Unprecedentedly for fish liver, the stereological design was exempt from model (biased) assumptions. Five (3 years old) animals per sex were studied in endogenous vitellogenesis, exogenous vitellogenesis, and spawning season end. Liver pieces for analysis were systematically sampled. Stereology was done in transmission electron microscopy (TEM) micrographs. Primary data generated relative volume estimates of the major cytoplasmic components. Such values were used for deriving absolute volumes (per cell and per liver). Lipid droplets did not show changes. As to other targets, trends at cell and liver levels were not always equal. If the hepatocyte was the reference space, the contents in mitochondria, dense bodies, glycogen, and cytosol changed seasonally, in both sexes. If taking the liver as the reference, changes attained the Golgi apparatus and rough endoplasmic reticulum (RER), besides dense bodies, glycogen (in females), and cytosol. The components volumes (namely per liver) were often positively (negatively for glycogen) correlated with the ovary weight, disclosing new associations and implications in fish. While also offering gold‐standard data for backing morphofunctional correlations and pathology, we revealed a new process by which females increase the amount of RER and Golgi throughout vitellogenesis, breaking from the idea on how this event happens in fish. Microsc. Res. Tech. 73:766–778, 2010. © 2010 Wiley‐Liss, Inc.
Gorham‐Stout disease of the temporal bone
Authors: Mowry Sarah , Canalis Rinaldo
Published: February 2010

Gorham‐Stout (GS) disease is a rare disease of the bone and is also known as massive osteolysis. Less than 200 cases have been reported in the world literature. A 29‐year‐old female with a diagnosis of GS disease was identified. She complained of aural fullness and tinnitus bilaterally. Demineralization and moth‐eaten changes of the osseous structures of the skull base and posterior fossa were prominent. The left mastoid air cells were opacified and erosion extended to the left jugular foramen, left hypoglossal canal, left stylomastoid process, and left eustachian tube. The radiographic findings and brief literature review are presented. Laryngoscope, 2010
Free‐Radical Propagation Kinetics of N‐Vinyl Formamide in Aqueous Solution Studied by PLP–SEC
Authors: Stach Marek , Lacík Igor , Kasák Peter , Chorvát Dušan , Saunders Alan J. , Santanakrishnan Sandhya , Hutchinson Robin A.
Published: February 2010

The propagation rate coefficients, kp, were determined for free‐radical polymerization of N‐vinyl formamide (NVF) in aqueous solution by pulsed‐laser‐initiated polymerization in conjunction with size‐exclusion chromatography. The polymerizations were carried out in the temperature range from 5 to 60 °C for concentrations between 3 and 100 wt.‐% NVF. A six‐fold decrease in kp was observed between polymerization of NVF in dilute aqueous solution and in bulk monomer. Intermolecular hydrogen bonding and dipolar interactions between solvent molecules and the transition state structure for NVF propagation are proposed to be responsible for these observed solvent effects, which are compared to similar effects found for the aqueous solution polymerizations of nonionized methacrylic acid and N‐vinyl pyrrolidone (NVP). Batch aqueous‐phase polymerizations of NVF and NVP demonstrate that the difference in initial rates of fractional conversion correlates with the differences in kp values for these two monomers. 2D NMR is used to study transfer reactions that occur at higher temperatures and NVF concentrations to the formic group and to the polyNVF backbone.

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Excessive hoarding in Parkinson's disease
Authors: O'Sullivan Sean S. , Djamshidian Atbin , Evans Andrew H. , Loane Clare M. , Lees Andrew J. , Lawrence Andrew D.
Published: February 2010

Hoarding is seen in several psychiatric conditions, but has not been specifically assessed in Parkinson's disease (PD). This study investigates hoarding tendency amongst patients with PD, and its association with impulsive‐compulsive spectrum behaviors (ICBs). We compare clinical features, measures of hoarding, impulse buying, self‐control, obsessive‐compulsive symptoms, depression, and anxiety in 39 patients with PD with ICBs (PD + ICB), 61 patients with PD without ICBs (PD − ICB), and 50 healthy controls. A much higher proportion of PD + ICB (27.8%) than PD − ICB (3.5%) were hoarders (P = 0.001). 6% of healthy controls were hoarders. Compulsive shoppers scored higher than other varieties of ICB on excessive acquisition measures. Hoarding correlated positively with impulsive buying, obsessive‐compulsive symptoms, PD duration, and negatively with self‐control measures. Using multivariate regression analyzes, the presence of ICBs and measures of impulsive buying were the only variables independently associated with hoarding in PD. The association of hoarding with other ICBs and low trait impulse control suggests that excessive hoarding is related to the spectrum of impulsive behaviors in PD. © 2010 Movement Disorder Society
Feeling‐of‐knowing in episodic memory in patients with Parkinson's disease with various motor symptoms
Authors: Yu Rwei‐Ling , Wu Ruey‐Meei , Tai Chun‐Hwei , Lin Chin‐Hsien , Hua Mau‐Sun
Published: February 2010

The aim of this study was to examine metamemory in patients with Parkinson's disease (PD) with different dominant motor symptoms. This is a prospective case‐control study. Fifty‐five PD patients [25 patients with tremor‐dominant (TD) motor symptoms and 30 patients with akinetic and rigidity‐dominant (ARD) motor symptoms] and 30 normal controls were studied. The two patient groups were similar in terms of age, level of education, disease duration, and disease severity. Metamemory was measured using the experimental metamemory task [feeling‐of‐knowing (FOK) paradigm]. In addition, memory and executive functions were determined using detailed cognitive tests. In comparison with normal subjects and TD patients, ARD patients exhibited impaired FOK accuracy (P = 0.007). Furthermore, correlation analysis revealed an intergroup differential pattern, which indicated that FOK accuracy was primarily related to memory ability in ARD patients and executive function in TD patients. Our results provide evidence of impaired metamemory in the early stages of PD with ARD rather than TD motor symptoms. These findings might be useful for designing specific medical care strategies for ARD patients. Further studies are needed to determine whether impaired metamemory is an early predictor for brain alteration in PD patients. © 2010 Movement Disorder Society
On the stabilization of reaction–diffusion systems modeling a class of man‐environment epidemics: A review
Authors: Aniţa Sebastian , Capasso Vincenzo
Published: February 2010

A two‐component reaction–diffusion system modeling a class of spatially structured epidemic systems is considered. The system describes the spatial spread of infectious diseases mediated by environmental pollution. A relevant problem, related to the possible eradication of the epidemic, is the so‐called zero‐stabilization. In a series of papers, necessary conditions and sufficient conditions of stabilizability have been obtained. It has been proved that it is possible to diminish exponentially the epidemic process, in the whole habitat, just by reducing the concentration of the pollutant in a nonempty and sufficiently large subset of the spatial domain.

In order to model the possible seasonal variability of the environmental conditions, the relevant parameters need to be assumed to be periodic, all with the same period. Corresponding results for the time homogeneous case are presented too. Copyright © 2010 John Wiley & Sons, Ltd.
Nonautonomous fragmentation equation via evolution semigroups
Authors: Arlotti L. , Banasiak J.
Published: February 2010

In this paper we investigate an initial‐value problem modelling multiple fragmentation process with time dependent coefficients. Our approach is to use evolution semigroups which allows to build on the substochastic semigroup theory that yields stronger results than obtained in earlier works. Copyright © 2010 John Wiley & Sons, Ltd.