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Ladder-like polymers with different degrees of ladder were synthesized by copper-mediated atom transfer radical polymerization (ATRP) of poly(2-methacryloyloxyethyl methacrylate) with α, α′-dibromo- p-xylene, as a bifunctional initiator. The livingness of ATRP was confirmed by kinetic analysis. The size of ladder-like sequence in ladder-like polymer was controlled by the hydrolysis. It was found that the remaining ester group was preferentially hydrolyzed and then the ester group of the ladder unit was hydrolyzed due to the high mobility of the remaining ester groups and high chemical resistance of the ladder-like unit. The products are block copolymers with different content of ladder-like sequences in the range of 18.2-73.5 mol%. All products showed two different glass transition temperatures (Tgs) and their high Tg was owing to the ladder-like sequence. The segregation of cyclic units in the ladder-like polymers was effective in improving the thermal stability of products. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Iron-containing complex hydrides are a fascinating class of materials for hydrogen storage applications because they consist of abundant iron and usually contains [FeH 6 ] 4− complexes, resulting in high hydrogen densities. In this study, we synthesized theoretically predicted Li 3 AlFeH 8 , which has the highest gravimetric hydrogen density of all transition metal complex hydrides, through a hydrogenation reaction of LiH, AlH 3 , and pure iron powder mixture under high pressure. The reaction process was observed in situ using a synchrotron radiation x-ray diffraction technique to clarify its reaction kinetics. The reaction temperature and pressure were changed to optimize reaction conditions for obtaining single phase Li 3 AlFeH 8 . Unfortunately, we did not obtain single phase Li 3 AlFeH 8 because the reaction was slow. In addition, there were other phases with similar thermodynamic stabilities to that of Li 3 AlFeH 8 . Another novel hydride, LiAlFeH 6 , was found to be synthesized above 850 °C at 9 GPa. [ABSTRACT FROM AUTHOR]

Background: The importance of multidisciplinary discussion (MDD) for diagnosing interstitial lung disease (ILD) is emphasized by several international guidelines. While initial diagnoses are often provisional and require periodic re-evaluation, there is a lack of literature regarding the role of follow-up MDD in clinical practice., Methods: From September 2020 to January 2022, patients underwent an initial MDD (MDD1) based on clinical, radiological, and pathological evaluations. Each diagnosis was assigned a confidence level. One year later, a second MDD (MDD2) was conducted for re-evaluation, based on subsequent clinical and radiological information. Changes in diagnosis and confidence levels between MDD1 and MDD2 were assessed., Results: Among 52 patients enrolled in both MDDs, the diagnosis for 13 (25%) was revised at MDD2. Of these, 10 patients were initially diagnosed with unclassifiable ILD, and 3 received a low confidence diagnosis of either idiopathic pulmonary fibrosis or idiopathic nonspecific interstitial pneumonia. The most common diagnostic revision was due to the deterioration after antigen exposure or improvement after antigen avoidance, which resulted in a revised diagnosis of HP at MDD2., Conclusions: Our findings underscore the importance of periodic reassessment of MDD to improve the accuracy of ILD diagnosis. This study highlights the significance of longitudinal clinical and radiological evaluation for diagnostic revision, even in situations when rebiopsy is not feasible., Competing Interests: Declaration of competing interest Y.Iijima reports grants from Japan Society for the Promotion of Science. H. Furusawa reports grants from Japan Society for the Promotion of Science outside the submitted work. T.Okamoto reports endowment from Nippon Boehringer Ingelheim Co., Ltd. Y. Miyazaki reports grants from Nippon Boehringer Ingelheim Co., Ltd. and Chugai Pharmaceutical Co., Ltd., and personal fees from Nippon Boehringer Ingelheim Co., Ltd. and AstraZeneca K.K., outside the submitted work. The remaining authors have no disclosures., (Copyright © 2024 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.)

We herein report a rare case of hypersensitivity pneumonitis (HP) that was initially demonstrated as solitary pure ground-glass opacity (GGO) on chest computed tomography (CT). A 51-year-old woman with a history of breast cancer underwent follow-up CT, which revealed solitary pure GGO. The patient developed exertional dyspnea after two years, and CT revealed diffuse centrilobular nodules in addition to GGO, which had increased in size. An antigen avoidance test was performed to diagnose HP, leading to the resolution of CT abnormalities, including the GGO. Our findings suggested that nonfibrotic HP can present as solitary pure GGO.

Background: There is limited data on the impact of COVID-19 epidemic on the number of orthopaedic surgeries in Japan., Methods: We conducted a nationwide hospital survey asking for the monthly number of orthopaedic surgeries performed at each facility from January 2019 to June 2021. Those facilities that had performed at least 100 surgeries in 2019 were included for analyses. The facilities were further grouped by prefecture and by hospital characteristics. A brief health economic evaluation was also performed. Risk ratios were compared using univariate analyses with P < 0.05 considered statistically significant., Results: Questionnaire was sent to 1988 hospitals with 1671 hospitals (84%) responding. The survey data indicated a total number of orthopaedic surgeries decreased in 2020 compared to 2019 (1,061,541 vs 1,119,955 P < 0.01), and also for the first six months of 2021 compared to the same period in 2019 (530,388 vs 550,378 P < 0.01). In 2020, over 50% of all facilities in nearly all of the prefectures saw a decline in surgical procedures. The risk of incurring more than a 25% decease in the number of surgeries was significantly higher in 2020 for class I designated medical institutions compared to those that were not designated for any types of infectious diseases among the institutions with a tertiary emergency medical center in 2020 (crude risk ratio 2.9: 95% CI 1.2-7.4, p = 0.02) and in 2021 (crude risk ratio 4.7: 95% CI 1 0.9-12.1, p < 0.01). The estimated total nationwide decrease of revenue were in the range of approximately ¥29.2 to ¥116.8 billion per year for orthopaedic surgeries alone., Conclusion: There was a statistically significant decrease in the number of orthopaedic surgeries in Japan. The magnitude of the decline varied by prefectures and hospital characteristics, with the greater impact imposed on medical institutions with higher classification functions. The estimated immediate health economic impact was sizable., Competing Interests: Declaration of competing interest No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript. The first author reports personal speaker fees from Johnson & Johnson K·K., Pfizer Japan, 3 M Japan, Stryker Japan, Taisho Toyama Pharmaceutical, MSD K.K., Hisamitsu Pharmaceutical, Kaken Pharmaceutical, Astellas Pharma, Smith＆Nephew, Daiichi Sankyo Company, outside the submitted work., (Copyright © 2023 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Background: The emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has increased the incidence of community-onset MRSA infection. Respiratory tract infections caused by MRSA has been noted for their severity; however, repeated relapses that require extended antibiotic therapy are rare., Case Presentation: We report a case of relapsing bronchopneumonia caused by CA-MRSA in a 56-year-old man. The patient responded to antibiotics, but repeatedly relapsed after stopping treatment. MRSA was consistently isolated from airway specimens during each relapse. Extended oral antibiotic treatment with trimethoprim/sulfamethoxazole (TMP/SMX) for 6 months achieved infection control. Whole-genome sequencing of the isolated strain revealed that the causative agent was sequence type (ST)1/staphylococcal cassette chromosome mec (SCCmec) type IVa, a clone that is rapidly increasing in Japan., Discussion and Conclusions: This patient had an unusual course of MRSA bronchopneumonia with repeated relapses. Although the choice of antibiotics for long-term use in MRSA respiratory tract infections has not been well established, TMP/SMX was effective and well tolerated for long-term therapy in this case. The clinical course of infections related to the rapid emerging clone, ST1/SCCmec type IVa warrants further attention., (© 2024. The Author(s).)

Nontuberculous mycobacterial (NTM) infection sometimes leads to the development of pulmonary artery aneurysm (PAA), a rare but life-threatening complication. We herein report a 64-year-old woman with a history of NTM infection who presented with severe hemoptysis. Computed tomography revealed a ruptured PAA, which was treated successfully with pulmonary artery embolization. Subsequent right total pneumonectomy was performed to control infection. This case emphasizes the need to consider PAA in patients with NTM infection who present with hemoptysis. Early detection and appropriate management are critical for preventing this fatal complication.

Background: Exposure assessment is integral to the diagnosis of hypersensitivity pneumonitis (HP). Although the clinical relevance of exposed antigens is essential for the assessment, many of the previous guidelines or reports have only evaluated simple exposure histories or immunological tests. To overcome this problem, the Exposure Assessment Form (EAF) was developed as an assessment tool for classifying the exposure grade from G0 to G4. The EAF was modified from the description in the Japanese clinical practice guide 2022 for HP published by the Japanese Respiratory Society., Methods: One hundred and seventy-two consecutive patients with interstitial lung disease who underwent multidisciplinary discussion (MDD) at our hospital were retrospectively examined. We assessed whether the use of the EAF improved the diagnostic performance of the international guideline of HP. We also evaluated whether the exposure grade affected the prognosis of HP., Results: Even when a HP diagnosis was made with a confidence of 70% or higher according to the international guideline, less than half of these cases resulted in a final diagnosis of HP when the exposure grades were lower than G3. When the result of the EAF was integrated into the exposure definition of the international guideline, the specificity of the diagnostic performance improved, while sensitivity was maintained. Furthermore, HP patients with an exposure grade of G3 or higher showed a tendency to take a longer time to initiate medication., Conclusions: This is the first study to evaluate the clinical relevance of possible antigens using the EAF. Assessing the exposure grade prevents overdiagnosis and improves the diagnostic performance of the international guideline., (© 2024. The Author(s).)

Background: This study compared the clinical results of fracture stems and conventional stems using the same glenoid component in reverse shoulder arthroplasty for proximal humerus fractures in the elderly., Methods: This retrospective study included 35 patients who underwent Grammont-type reverse shoulder arthroplasty for proximal humerus fractures from 2014 to 2020. The average age at surgery was 79.2 (range, 65-92) years, with 33 female shoulders. Fracture types per Neer classification were 3-part fracture, 4-part fracture, in 13 and 22 shoulders, respectively. The final follow-up period was 35 (range, 24-81) months. The Constant score, American Shoulder and Elbow Surgeons score, shoulder range of motion, and healing of greater tuberosities at the final follow-up of AEQUALIS™ REVERSED (Conventional stem group: n = 15) and AEQUALIS™ REVERSED FX (Fractured stem group: n = 20) were retrospectively investigated., Results: There were no statistically significant differences in age at surgery, sex, body mass index, fracture type, waiting time from injury to surgery, or preoperative general condition between the groups. The Constant and American Shoulder and Elbow Surgeons scores of the fractured stem group were significantly higher than those of the conventional stem group (P = 0.038 and P = 0.023, respectively). The anterior elevation and external rotation at the side of the fractured stem group also showed significantly higher values than those of the conventional stem group (fractured stem group vs. conventional stem group: anterior elevation 127° ± 25° vs. 105° ± 35°, P = 0.041; external rotation 28° ± 13° vs. 13° ± 12°, P = 0.015). The greater tuberosity healing rate was 46.7% (7/15) in the conventional stem group and 85.0% (17/20) in the fractured stem group (P＝0.027)., Conclusions: The findings suggest that use of a fracture-specific stem rather than a conventional stem in Grammont-type reverse shoulder arthroplasty for proximal humerus fractures improves tuberosity healing, postoperative range of motion, and clinical scores., Competing Interests: Declaration of competing interest The authors have no conflicts of interest directly relevant to the content of this article., (Copyright © 2022. Published by Elsevier B.V.)

Background: Frozen shoulder (FS) is a pathological condition that involves a painful and stiff shoulder joint, most commonly in people aged 40-60 years. Most literature supports treatment with physical therapy (PT), although some studies have demonstrated years of continuing pain and functional deficits. Manipulation under anesthesia is effective at eliminating the contracture of intra-articular lesions for refractory FS. This study aimed to compare whether manipulation under anesthesia or PT is a more effective treatment in refractory FS., Methods: This study was a prospective observational study. A total of 102 patients with refractory FS were enrolled in this study in the medical records, all of whom had severe and multidirectional loss of motion and thickening of the joint capsule and coracohumeral ligament on magnetic resonance imaging. Fifty-one patients were in the manipulation under brachial plexus block (MUB) group (34 females, median age: 57 years), and 51 patients were in the PT group (34 females, median age: 59 years). The MUB procedure consisted of the conventional method with additional adduction manipulation, in which one examiner initially abducted the shoulder joint as much as possible. We recorded the visual analog scale, shoulder range of motion, and American Shoulder and Elbow Surgeons and Constant Scores at the initial baseline visit and at the 1-, 3-, 6-, and 12-month follow-ups. The total cost was calculated from the medical records, and cost-effectiveness was evaluated using quality-adjusted life year and incremental cost-effectiveness ratio., Results: Visual analog scale ( P  < .001), range of motion ( P  < .001), and American Shoulder and Elbow Surgeons and Constant Scores ( P  < .001) in the MUB group were significantly superior to those in the PT group at 1, 3, 6, and 12 months after treatment. The median cost and total quality-adjusted life year in the MUB and PT groups were $1375 versus $2751 and 2.95 versus 2.68, respectively, and the cost-effectiveness ratio between the MUB and PT groups was calculated as -$560., Conclusions: The new MUB procedure provides a shorter treatment period, better clinical outcomes, and higher cost-effectiveness in patients with refractory FS compared to PT., (© 2023 The Author(s).)

Background: A frozen shoulder (FS) is characterized by pain and limited range of motion (ROM). Although physical assessment of ROM is important for diagnosing and staging FS, ROM cannot be accurately assessed in clinical practice because of pain and muscle contraction. This study aimed to measure changes in shoulder joint ROM before and after anesthesia (ΔROM) in patients with FS and investigate the factors affecting these changes., Methods: This study included 54 patients (age, 55.6 ± 9.4 years; 17 males; disease duration, 6.6 ± 3.4 months) with FS before manipulation under transmission anesthesia. FS was defined as having a ROM in external rotation (ER) that was less than 50% of that in the unaffected shoulder. Pain at night and during motion was assessed using a numerical rating scale. Before anesthesia, the passive ROM of forward flexion (FF), abduction (AD), and ER were measured in the supine position. After confirming that the anesthesia was effective, passive ROM was measured again., Results: The ROM in the FF, AD, and ER after anesthesia was significantly higher than that before anesthesia ( P  < .001). ΔROM in the FF, AD, and ER was significantly correlated with pain at night (r = 0.51, P  < .001; r = 0.45, P  < .001; and r = 0.39, P  = .004, respectively). Furthermore, ΔROM in the ER was significantly correlated with pain during motion (r = 0.31, P  = .023) and disease duration (r = -0.31, P  = .021)., Conclusion: The ROM of the FS is susceptible to pain and muscle contraction. Interventions, such as physical therapy, may be recommended after pain relief., (© 2023 The Author(s).)

Background: Adhesive capsulitis (AC) is characterized by pain and limited range of motion, caused by stiffness of the joint capsule and coracohumeral ligament. On the other hand, there have been few reports on muscle stiffness in AC. The purpose of this study was to assess muscle stiffness in patients of AC with a portable and noninvasive device, Myoton PRO. We hypothesized that muscle stiffness around shoulder joint increases in AC., Methods: At first, we surveyed correlation between Myoton PRO and shear wave elastography with phantoms. Second, reproducibility and repeatability of healthy volunteers with Myoton PRO were evaluated. Finally, muscle stiffness was measured in 40 patients who were diagnosed with AC. Muscle stiffness was quantitatively measured with Myoton PRO. We compared the stiffness of the anterior deltoid (AD), pectoralis major, and latissimus dorsi (LD) in AC patients on both the affected and nonaffected sides., Results: Correlation coefficient in shear wave elastography and Myoton PRO was 0.99( P  = .001). Reliability of intraoperator and interoperator with Myoton PRO was 0.9 or higher. Muscle stiffness values (N/m) of the AD, pectoralis major, and LD were 355 ± 61, 252 ± 54, 207 ± 51 in the affected sides and 328 ± 50, 252 ± 41, 186 ± 37 in the nonaffected sides, and the differences were significant in the AD and LD ( P  = .005, P  = .002, respectively)., Conclusions: We used Myoton PRO to evaluate muscle stiffness in AC. The AD and LD muscles of AC patients were significantly stiffer on the affected side compared to the nonaffected side., (© 2022 The Authors.)