Evolution of Beryllium and Boron in the Inhomogeneous Early Galaxy

A model of supernova-driven chemical evolution of the Galactic halo, recently proposed by Tsujimoto, Shigeyama, & Yoshii (1999, ApJL, 519, 64), is extended in order to investigate the evolution of light elements such as Be and B (BeB), which are produced mainly through spallative reactions with Galactic cosmic rays. In this model each supernova sweeps up the surrounding interstellar gas into a dense shell and directly enriches it with ejecta which consist of heavy elements produced in each Type II supernova with different progenitor masses. We propose a two-component source for GCRs such that both interstellar gas and fresh SN ejecta engulfed in the shell are accelerated by the shock wave. Our model results include: (1) a prediction of the intrinsic scatter in BeB and [Fe/H] abundances within the model, (2) a successful prediction of the observed linear trend between BeB and [Fe/H], (3) a proposal for using BeB as a cosmic clock, as an alternative to [Fe/H], and (4) a method for possibly constraining the BBN model from future observations of metal-poor stars.Comment: 3 color figures in 7 pages, accepted by ApJ Letter

Prevalence and Distribution of Ossified Lesions in the Whole Spine of Patients with Cervical Ossification of the Posterior Longitudinal Ligament A Multicenter Study (JOSL CT study)

Ossification of the posterior longitudinal ligament (OPLL) can cause severe and irreversible paralysis in not only the cervical spine but also the thoracolumbar spine. To date, however, the prevalence and distribution of OPLL in the whole spine has not been precisely evaluated in patients with cervical OPLL. Therefore, we conducted a multi-center study to comprehensively evaluate the prevalence and distribution of OPLL using multi-detector computed tomography (CT) images in the whole spine and to analyze what factors predict the presence of ossified lesions in the thoracolumbar spine in patients who were diagnosed with cervical OPLL by plain X-ray. Three hundred and twenty-two patients with a diagnosis of cervical OPLL underwent CT imaging of the whole spine. The sum of the levels in which OPLL was present in the whole spine was defined as the OP-index and used to evaluate the extent of ossification. The distribution of OPLL in the whole spine was compared between male and female subjects. In addition, a multiple regression model was used to ascertain related factors that affected the OP-index. Among patients with cervical OPLL, women tended to have more ossified lesions in the thoracolumbar spine than did men. A multiple regression model revealed that the OP-index was significantly correlated with the cervical OP-index, sex (female), and body mass index. Furthermore, the prevalence of thoracolumbar OPLL in patients with a cervical OP-index ≥ 10 was 7.8 times greater than that in patients with a cervical OP-index ≤ 5. The results of this study reveal that the extent of OPLL in the whole spine is significantly associated with the extent of cervical OPLL, female sex, and obesity

Choice of Surgical Procedure for Cervical Ossification of the Posterior Longitudinal Ligament

In cervical ossification of the posterior longitudinal ligament (OPLL), spinal cord compression causes neurologic symptoms [...

Research History, Pathology and Epidemiology of Ossification of the Posterior Longitudinal Ligament and Ligamentum Flavum

Ossification of the spinal ligaments was first reported by Key in 1838 [...

Dexamethasone Regulates EphA5, a Potential Inhibitory Factor with Osteogenic Capability of Human Bone Marrow Stromal Cells

We previously demonstrated the importance of quality management procedures for the handling of human bone marrow stromal cells (hBMSCs) and provided evidence for the existence of osteogenic inhibitor molecules in BMSCs. One candidate inhibitor is the ephrin type-A receptor 5 (EphA5), which is expressed in hBMSCs and upregulated during long-term culture. In this study, forced expression of EphA5 diminished the expression of osteoblast phenotypic markers. Downregulation of endogenous EphA5 by dexamethasone treatment promoted osteoblast marker expression. EphA5 could be involved in the normal growth regulation of BMSCs and could be a potential marker for replicative senescence. Although Eph forward signaling stimulated by ephrin-B-Fc promoted the expression of ALP mRNA in BMSCs, exogenous addition of EphA5-Fc did not affect the ALP level. The mechanism underlying the silencing of EphA5 in early cultures remains unclear. EphA5 promoter was barely methylated in hBMSCs while histone deacetylation could partially suppress EphA5 expression in early-passage cultures. In repeatedly passaged cultures, the upregulation of EphA5 independent of methylation could competitively inhibit osteogenic signal transduction pathways such as EphB forward signaling. Elucidation of the potential inhibitory function of EphA5 in hBMSCs may provide an alternative approach for lineage differentiation in cell therapy strategies and regenerative medicine

The impact of sarcopenia on the results of lumbar spinal surgery

Objectives: As the population ages, the number of lumbar spinal surgeries performed on sarcopenic patients will increase. The purpose of this study was to investigate the prevalence of sarcopenia and evaluated its impact on the results of lumbar spinal surgery. Methods: This study included 2 groups: One group consisted of patients who underwent whole-body dual-energy X-ray absorptiometry (DXA) scanning before the option of undergoing surgery for lumbar spinal disease (LSD group) and a second group consisted of patients underwent DXA scanning for osteoporosis screening under hospital watch at the geriatric medicine department (control group). In order to evaluate the impact of sarcopenia on the clinical outcome of lumbar spinal surgery, the Japanese Orthopedic Association (JOA) score, the recovery rate based on the JOA score, and visual analogue scale (VAS) scores for lower back pain, lower extremity pain, and lower extremity numbness were compared within the LSD group. Results: The prevalence of sarcopenia showed no statistical difference between groups (control group, 50.7%; LSD group, 46.5%). In the LSD group, while the changes in VAS scores showed no statistical difference between the nonsarcopenia subgroup and sarcopenia subgroup, the sarcopenia subgroup demonstrated inferior JOA scores and recovery rates at the final follow-up when compared with the nonsarcopenia subgroup (P < 0.05). Conclusions: This study demonstrated a high prevalence of sarcopenia among the elderly populations in Japan and a negative impact of sarcopenia on clinical outcomes after lumbar spinal surgery. Keywords: Lumbar canal stenosis, Sarcopeni

Surgical outcomes for lumbar spinal canal stenosis with coexisting cervical stenosis (tandem spinal stenosis): a retrospective analysis of 565 cases

Abstract Background Concurrent cervical and lumbar spinal canal stenosis is known as tandem spinal stenosis (TSS). As research on TSS is limited, there is no consensus on the optimal surgical approach to this problem. We evaluated the prevalence and clinical characteristics of TSS in patients with symptomatic lumbar spinal canal stenosis (LCS). Methods The authors performed a retrospective analysis of the outcomes of 565 patients who underwent lumbar surgeries performed for symptomatic LCS. In all the patients, both the cervical and lumbar regions were evaluated preoperatively, and we compared TSS patients and non-TSS patients in terms of multiple clinical parameters. In the TSS patients, we investigated the ratio and clinical outcomes of additional cervical surgeries performed on TSS patients. Results Two hundred two cases (35.8%) were considered to be TSS. Twenty-eight patients (5.0%) underwent a cervical operation during the follow-up period. There were no differences between the radiographic TSS patients and non-TSS patients in terms of preoperative lumbar-Japanese Orthopedic Association (L-JOA) scores, postoperative L-JOA scores, and the L-JOA recovery rate (14.8 ± 4.4 points vs 14.2 ± 4.6 points, 23.9 ± 4.3 points vs 23.1 ± 4.5 points, 63.7 ± 28.2% vs 60.3 ± 27.9%, respectively), while the TSS group included a greater number of hypertension cases. The recovery rate L-JOA scores of patients who underwent additional cervical surgeries were significantly lower compared with the rate of patients who experienced treatment for only lumbar lesions (62.8 ± 25.8% vs 39.8 ± 35.5%, p = 0.0003). However, additional cervical surgery still improved both the cervical myelopathy-Japanese Orthopedic Association (C-JOA) and L-JOA scores in TSS patients with symptomatic cervical lesion (from 10.3 ± 2.8 points to 12.1 ± 3.0 points, p = 0.0302; from 14.8 ± 7.3 points to 19.9 ± 5.0 points, p = 0.0331, respectively). In these patients, there were no significant differences in the recovery rate of both C-JOA and L-JOA scores between the single-stage surgery group and the staged surgery group (40.7 ± 35.8% vs 20.7 ± 16.1%; 50.9 ± 25.1% vs 34.2 ± 39.3%, respectively). Conclusions Radiographic co-existing cervical stenosis did not affect surgical outcomes for LCS, although symptomatic cervical lesion affected neurological score after lumbar surgery. An additional surgery for cervical lesion significantly improved neurological findings in TSS patients

The Real‐World Effect of 12 Months of Romosozumab Treatment on Patients With Osteoporosis With a High Risk of Fracture and Factors Predicting the Rate of Bone Mass Increase: A Multicenter Retrospective Study

ABSTRACT Excluding clinical trials, there is limited evidence on the effect of 12 months of romosozumab treatment on bone mineral density (BMD) increase in real‐world clinical practice because its use has only been approved recently. Thus, this study aimed to investigate the real‐world effect of 12 months of romosozumab treatment on BMD increase and identify factors that predict the rate of BMD increase after 12 months of romosozumab treatment. We retrospectively investigated 106 patients who completed a 12‐month romosozumab treatment for osteoporosis with a high risk of fractures at four hospitals from March 2020 to March 2022. The univariate and multiple regression analyses were performed to analyze the concurrent effects of various factors on the BMD increase after the 12‐month romosozumab treatment. After 1 year of treatment, the lumbar spine BMD increased by 14.6%, and femoral neck BMD increased by 5.1%. Univariate regression analysis found that male sex, high tartrate‐resistant acid phosphatase 5b (TRACP‐5b) value before romosozumab administration, absence of osteoporosis medications before romosozumab administration, and low baseline lumbar spine BMD were associated with the extent of lumbar spine BMD increase. Moreover, stepwise multiple regression analysis found that the TRACP‐5b value before romosozumab administration was a significant predictor of the rate of lumbar spine BMD increase after 1 year of romosozumab administration. In conclusion, our results demonstrated the effectiveness of the 12‐month romosozumab treatment for osteoporosis with a high risk of fractures and the TRACP‐5b value before romosozumab administration was a significant predictor of the rate of lumbar spine BMD increase after 1 year of romosozumab administration. Our findings could help establish more efficient treatment strategies for patients with osteoporosis at a high risk of fracture. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research