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Study Design: A retrospective cohort analysis. Objective: To determine the effect of biological agents (BAs) on the development and progression of cervical spine lesions and identify predictors of lesion progression. Summary Of Background Data: The introduction of BAs has facilitated advances in the treatment of rheumatoid arthritis (RA). BAs reduce disease activity and limit structural joint damage. However, the effect of BAs on cervical spine lesions remains unclear. Methods: Thirty-eight subjects who received more than 2 years of continuous BA treatment were enrolled. The mean x-ray interval was 4.4 years. RA activity was evaluated by disease activity score (DAS)-C reactive protein (CRP) and matrix metalloproteinase (MMP)-3. Radiographical definitions of cervical lesions were atlanto-dental interval (ADI) more than 3 mm for atlanto-axial subluxation (AAS), Ranawat value less than 13 mm for vertical subluxation (VS), and anterior or posterior listhesis more than 2 mm for subaxial subluxation (SS). Definitions of radiographical progression were an increase of ADI more than 2 mm for AAS, a decrease of both Ranawat and Redlund-Johnell values more than 2 mm for VS, and an increase of listhesis more than 2 mm for SS. Results: RA activity responded dramatically to BA therapy (DAS-CRP from 4.3 to 2.3, P < 0.01; MMP-3 from 207.9 ng/mL to 105.6 ng/mL, P < 0.01). Baseline radiographical evaluation showed no pre-existing cervical spine lesions in 12 cases, AAS in 15 cases, and VS in 11 cases. Radiological progression was found in 1 (8%) patient in the no lesion group, 12 patients (80%) in the AAS group, and 9 patients (80%) in the VS group. The incidence of progression was significantly lower in the no lesion group compared with the other groups. Multivariate regression analysis showed that the presence of pre-existing cervical lesions was the single greatest predictor of progression. Conclusion: BAs prevented the development of de novo cervical spine lesions in patients with RA, but failed to inhibit progression of pre-existing RA lesions. [ABSTRACT FROM AUTHOR]

Abstract: This paper discusses the effects of small amount of Al contamination (<0.1wt%) on high-temperature strength and microstructure of the 9Cr–ODS steel. Increasing Al concentration degraded the ultimate tensile strength as well as the 0.2% proof stress at 973K and 1073K accompanied by decreasing fraction of the elongated grain, i.e., residual-α ferrite acting as reinforcement phase. The decrease of residual-α ferrite proportion provided by increasing Al is contrary to general behavior of conventional steels. Computer simulation on ferrite to austenite phase transformation suggested that the fine oxide dispersion in the elongated ferrite could be attributable to the preferential partitioning of Ti and W in ferrite than in austenite at hot-extrusion process. [Copyright &y& Elsevier]

Abstract: In order to examine irradiation effect on creep rupture strength of Oxide Dispersion Strengthened (ODS) steel claddings, the in-pile creep rupture test was conducted using Material Testing Rig with Temperature Control (MARICO)-2 in the experimental fast reactor JOYO. Fourteen creep rupture events were successfully detected by the temperature change in each capsule and the gamma-ray spectrometry of the cover gas. Time to creep ruptures of six ODS steel specimens were identified by means of Laser Resonance Ionization Mass Spectrometry (RIMS), and no irradiation effect on creep rupture strength was confirmed within the irradiation condition in the MARICO-2 test. [Copyright &y& Elsevier]

Abstract: PbBr2 single crystals were grown by a vertical Bridgman method. The objective of this work is to examine the following two: (i) how the crystal quality is influenced by purification, (ii) how the crystal quality is influenced by growth rate. The following results were obtained. (1) The crystals grown from the materials of 99.99% and 99.999% purity were not transparent if they were not purified. On the other hand, a transparent crystal was obtained even from the material of 99.99% purity when it was refined by directional freezing as well as vacuum distillation. (2) It was found that very slow growth rate was needed to grow transparent crystals. [Copyright &y& Elsevier]

Abstract 9Cr-ODS steel claddings consisting of tempered martensitic matrix, showed prominent creep rupture strength at 1000 °C, which surpassed that of heat-resistant austenitic steels although creep rupture strength of tempered martensitic steels is generally lower than that of austenitic steels at high temperatures. The measured creep rupture strength of 9Cr-ODS steel claddings at 1000 °C was higher than that from extrapolated creep rupture trend curves formulated using data at temperatures from 650 to 850 °C. This superior strength seemed to be owing to transformation of the matrix from the α-phase to the γ-phase. The transient burst strengths for 9Cr-ODS steel were much higher than those for 11Cr-ferritic/martensitic steel (PNC-FMS). Cumulative damage fraction analyses suggested that the life fraction rule can be used for the rupture life prediction of 9Cr-ODS steel and PNC-FMS claddings in the transient and accidental events with a certain accuracy. [ABSTRACT FROM AUTHOR]

The growth of oxide particles in FeCrAl- oxide dispersion strengthened steel (ODSS) considering an accident condition of the light-water reactor at above 1500 K was studied by using a high-temperature annealing. Oxide particles grew from 9 nm to more than 50 nm as maximum at 1623 K for 27 h, with decreasing their number density in two orders of magnitude. Most of the oxide particles in 15Cr-7Al were identified as YAM or YAP, while the oxide particles in 15Cr-7Al-0.4Zr were identified trigonal Y 4 Zr 3 O 12 . Zr addition to 15Cr-7Al ODSS accelerated the growth of the oxide particles, which is quite contrary to the effect of Zr addition during sintering as suggested in the literature. The kinetics of coarsening was characterized by an equation of Ostwald ripening. The diffusion activation energies obtained in the present materials were quite larger than the conventional diffusion activation energy of Y in alpha-iron. Gibbs free energy of oxides should be considered to discuss the coarsening. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to elucidate postoperative outcomes in patients with spinal metastases of prostate cancer, with a focus on patient-oriented assessments., Methods: This was a prospective multicenter registry study involving 35 centers. A total of 413 patients enrolled in the Japanese Association for Spine Surgery and Oncology Multicenter Prospective Study of Surgery for Metastatic Spinal Tumors were evaluated for inclusion. The eligible patients were followed for at least 1 year after surgery. The Frankel Classification, Eastern Cooperative Oncology Group Performance Status, visual analog scale for pain, face scale, Barthel Index, vitality index, indications for oral pain medication, and the EQ-5D-5L questionnaire were used for evaluating functional status, activities of daily living, and patient motivation., Results: Of the 413 eligible patients, 41 with primary prostate cancer were included in the study. The patient-oriented assessments indicated that the patients experienced postoperative improvements in quality of life and motivation in most items, with the improvements extending for up to 6 months. More than half of the patients with Frankel classifications B or C showed improved neurological function at 1 month after surgery, and most patients presented maintained or improved their classification at 6 months., Conclusion: Surgical intervention for spinal metastases of prostate cancer significantly improved neurological function, quality of life, and motivation of the patients. Consequently, our results support the validity of surgical intervention for improving the neurological function and overall well-being of patients with spinal metastases of prostate cancer., Competing Interests: Declaration of competing interest The Authors declare that there is no conflict of interest., (Copyright © 2024 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

The resting zone (RZ) in mammalian growth plates is critical for maintaining and regulating chondrocyte turnover during longitudinal bone growth as a control tower and stem cell reservoir. Although recent lineage tracing studies have identified several markers for stem cells in the RZ, these markers only partially label chondrocytes in the RZ, suggesting that the resting chondrocytes (RCs) are a heterogeneous population with different types of stem cells. Since a comprehensive marker for RCs is still lacking, the RZ is generally determined based on ambiguous histological criteria, such as small and round chondrocytes without columnar formation, which may lead to inconsistencies among researchers. Therefore, in this study, we used single-cell RNA sequencing (scRNAseq) of growth plate chondrocytes followed by validation by fluorescence in situ hybridization (FISH) to precisely annotate cell clusters in scRNAseq and search for a marker of RCs. The scRNAseq analysis revealed that apolipoprotein E ( Apoe ) was the top-hit gene, which was ubiquitously expressed in the RC cluster. FISH confirmed that Apoe was exclusively localized to the histologically defined RZ. In newly generated Apoe -mCherry knock-in mice, we further confirmed that mCherry expression mirrored the distribution of Apoe -expressing chondrocytes in the RZ particularly after the formation of the secondary ossification center. These mCherry + RCs were slow cycling in vivo and exhibited stem cell properties both in vitro and in vivo . Moreover, APOE was detected in human growth plate RCs. These findings suggest that Apoe is a novel pan-RC marker in both mouse and human growth plates., Competing Interests: Conflict of interests The authors declare no competing interest.

Study Design: A retrospective analysis., Objective: This research sought to develop a predictive model for surgical outcomes in patients with cervical ossification of the posterior longitudinal ligament (OPLL) using deep learning and machine learning (ML) techniques., Summary of Background Data: Determining surgical outcomes assists surgeons in communicating prognosis to patients and setting their expectations. Deep learning and ML are computational models that identify patterns from large datasets and make predictions., Methods: Of the 482 patients, 288 patients were included in the analysis. A minimal clinically important difference (MCID) was defined as gain in Japanese Orthopaedic Association (JOA) score of 2.5 points or more. The predictive model for MCID achievement at 1 year post-surgery was constructed using patient background, clinical symptoms, and preoperative imaging features (x-ray, CT, MRI) analyzed via LightGBM and deep learning with RadImagenet., Results: The median preoperative JOA score was 11.0 (IQR: 9.0-12.0), which significantly improved to 14.0 (IQR: 12.0-15.0) at 1 year after surgery (P < 0.001, Wilcoxon signed-rank test). The average improvement rate of the JOA score was 44.7%, and 60.1% of patients achieved the MCID. Our model exhibited an area under the receiver operating characteristic curve of 0.81 and the accuracy of 71.9% in predicting MCID at 1 year. Preoperative JOA score and certain preoperative imaging features were identified as the most significant factors in the predictive models., Conclusion: A predictive ML and deep learning model for surgical outcomes in OPLL patients is feasible, suggesting promising applications in spinal surgery., Level of Evidence: 4., Competing Interests: Authors have no conflict of interest to declare., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Despite the increasing prevalence of cervical odontoid fractures in older adults, the treatment strategy is controversial. The objectives of the current study are to investigate the prognosis and complications of cervical odontoid fractures in elderly patients and to identify factors associated with worsening of ambulation after 6 months., Methods: This multicenter, retrospective study included 167 patients aged 65 years or older with odontoid fractures. Patient demographic and treatment data were investigated and compared according to the treatment strategy. To determine associations with worsening ambulation after 6 months, we focused on the treatment strategies (nonsurgical treatment [collar immobilization or halo vest], conversion to surgery, or initial surgery) and patients' background., Results: Patients who received nonsurgical treatment were significantly older, and patients who underwent surgery had more Anderson-D'Alonzo type 2 fractures. Of the patients initially treated nonsurgically, 26% later underwent surgery. Numbers of complications, including death, and degrees of ambulation after 6 months did not differ significantly among treatment strategies. Patients who had worsened ambulation after 6 months were significantly more likely to be older than 80 years, to have needed assistance with walking before injury, and to have cerebrovascular disease. Multivariable analysis showed that a score of ≥2 on the 5-item modified frailty index (mFI-5) was significantly associated with worsening ambulation., Conclusions: Preinjury mFI-5 scores of ≥2 were significantly associated with worsening ambulation 6 months after treatment of cervical odontoid fractures in older adults., (Copyright © 2023 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)