Gas-Phase Lubrication of ta-C by Glycerol and Hydrogen Peroxide. Experimental and Computer Modeling

Tetrahedrally coordinated hydrogen-free amorphous diamond-like carbon coating (denoted as ta-C) presents ultralow friction under boundary lubrication conditions at 80 °C in presence of OH-containing molecules. To understand the mechanism of ultralow friction, we performed gas-phase lubrication experiments followed by time-of-flight secondary ion mass spectrometry (ToF-SIMS) analyses and this using two simple molecules: deuterated glycerol and hydrogen peroxide. The experiments were complemented by computer simulations using the ReaxFF reactive force field. These simulations suggest a ta-C surface rich in sp^2 carbon with some reactive sp^1 carbon atoms, in agreement with previous energy filtered transmission electron microscopy (EFTEM) results. Sliding simulations show that the carbon surface atoms react with glycerol and hydrogen peroxide to form OH-termination. Moreover, the hydroxylation is then followed by the chemical dissociation of some of the glycerol molecules leading to the formation of water. This is in agreement with the secondary ion mass spectrometry (SIMS) analyses and mass spectrometer results obtained with gas-phase lubrication experiments with the same molecules. Both experimental and computer simulations strongly suggest that the hydroxylation of the carbon surface is at the origin of ultralow friction together with the formation of water-rich film in the sliding interface

DRU classificationに基づく特発性側弯症の適切な観察間隔の設定 多施設研究

Purpose: To determine the capability of the distal radius and ulna (DRU) classification for predicting the scoliosis progression risk within 1 year in patients with adolescent idiopathic scoliosis (AIS) and to develop simple recommendations for follow-up durations. Methods: Medical records of patients with AIS at two tertiary scoliosis referral centers were retrospectively reviewed for their DRU classification and major curve Cobb angles. Baseline DRU grades and Cobb angles with subsequent 1-year follow-up curve magnitudes were studied for scoliosis progression, which was defined as exacerbation of the Cobb angle by ≥ 6°. The relationship between DRU classification and scoliosis progression risk within 1 year was investigated. Patients were divided into three groups according to the Cobb angle (10°-19°, 20°-29°, ≥ 30°). Results: Of the 205 patients with 283 follow-up visits, scoliosis progression occurred in 86 patients (90 follow-up visits). Radius and ulna grades were significantly related to scoliosis progression (p 80% of patients within 1 year. Curve progression was less likely for grades R9 and U7. Most patients with more mature DRU grades did not experience progression, even with Cobb angles ≥ 30°. Conclusion: With R6, R7, and U5, scoliosis may progress within a short period; therefore, careful follow-up with short intervals within 6 months is necessary. R9 and U7 may allow longer 1-year follow-up intervals due to the lower progression risk.博士（医学）・甲第771号・令和3年3月15日© Springer-Verlag GmbH Germany, part of Springer Nature 2020This is a post-peer-review, pre-copyedit version of an article published in European spine journal. The final authenticated version is available online at: http://dx.doi.org/10.1007/s00586-020-06441-4

Karyotypical characteristics of two allopatric African populations of anhydrobiotic Polypedilum Kieffer, 1912 (Diptera, Chironomidae) originating from Nigeria and Malawi

The African chironomid Polypedilum vanderplanki Hinton, 1951 is the only chironomid able to withstand almost complete desiccation in an ametabolic state known as anhydrobiosis. The karyotypes of two allopatric populations of this anhydrobiotic chironomid, one from Nigeria and another from Malawi, were described according to the polytene giant chromosomes. The karyotype from the Nigerian population was presented as the reference chromosome map for P. vanderplanki. Both populations, Nigerian and Malawian, showed the same number of chromosomes (2n=8), but important differences were found in the band sequences of polytene chromosomes, and in the number and the arrangement of active regions between the two populations. Such important differences raise the possibility that the Malawian population could constitute a distinct new species of anhydrobiotic chironomid

外側環軸関節の関節症性変化のリスク増加に関連する要因; 後ろ向き研究

Purpose Atlantodens osteoarthritis and atlantoaxial osteoarthritis cause neck pain and suboccipital headaches. Currently, knowledge on the risk factors for atlantoaxial osteoarthritis is lacking. This study aimed to investigate the factors related to the increased risk of atlantoaxial osteoarthritis. Methods We analyzed computed tomography (CT) images of the upper cervical spine of 1266 adult trauma patients for whom upper cervical spine CT was performed at our hospital between 2014 and 2019. The degree of atlantoaxial osteoarthritis was quantified as none-to-mild (not having osteoarthritis) or moderateto- severe (having osteoarthritis). Risk factors associated with atlantoaxial osteoarthritis were identified using univariate and multivariable logistic regression analyses. Results The study group included 69.4% men, and the overall average age of the study population was 54.9 ± 20.4 years. The following factors were independently and significantly associated with atlantoaxial osteoarthritis in the multivariable logistic regression analysis: age in the sixth decade or older (odds ratio [OR], 20.5; 95% confidence interval [CI], 6.2‒67.2, p < 0.001), having calcific synovitis (OR, 4.9; 95% CI, 2.4‒9.9, p < 0.001), women sex (OR, 3.3; 95% CI, 1.9‒5.7, p = 0.002), and not having atlantodens osteoarthritis (OR, 2.1; 95% CI, 1.2‒3.8, p = 0.014). Conclusion In the multivariable logistic regression analysis, age in the sixth decade or older, calcification of the transverse ligament, being women, and not having atlantodens osteoarthritis were found to be significantly associated with atlantoaxial osteoarthritis. Delayed diagnosis and treatment can be avoided by focusing on these risk factors.博士（医学）・甲第873号・令和5年3月15

Examination of density and mixing ratio of barium preparations, using an originally created phantom

胃Ⅹ線検査に造影剤として用いられる硫酸バリウム懸濁液の濃度を,簡便に,客観的に決定する目的で,歯科用アルギン酸塩印象材を用いて,コインの図柄を写しとったファントムを制作した｡これを使って二種類の硫酸バリウム製剤の適正濃度(PD)を調べた結果,BARITOP PとBARICON MEALを単体,若くは混合した場合には,おおよそ,PD(W/V%)=0.75C+165(ただし,CはBARICON MEALの混合比(%))となった｡また,BARICON MEALはコントラストが高く,精密検査に有利だと考えられ,BARITOP PとBARICON MEALを混合すると濃度の許容範囲が広がるため,通常の検査に都合がよいと考えられた｡更に,このファントムは簡便に作成することができ,しかも,硫酸バリウム懸濁 液との親和性も良いことから,硫酸バリウム製剤やⅩ線TV装置の評価,増感紙･フィルム系の評価等にも応用できると考えられた｡A phantom copied designs of coins was created with alginate dental impression material to establish a objective, simple and easy method for deciding density of barium sulfate suspensions which are used for stomach X-ray examination as contrast media. As a result of examining proper density (PD) of two kind of barium preparations with this phantom, in case of BARITOP P and BARICON MEAL, PD were almost shown by the next equation : PD(W/V%)=0.75C+165(C meant content of BARICON MEAL (%)). As BARICON MEAL resulted in hight contrast, it was thought to be suitable for a close examination. Mixture of BARITOP P and BARICON MEAL was thought to be suited to a routine examination becouse of wide permissible level of density. This phantom would be able to apply to the test of balium preparations, X-ray TV systems, screen/film systems and so on

Brown adipose tissue dysfunction promotes heart failure via a trimethylamine N-oxide-dependent mechanism.

Low body temperature predicts a poor outcome in patients with heart failure, but the underlying pathological mechanisms and implications are largely unknown. Brown adipose tissue (BAT) was initially characterised as a thermogenic organ, and recent studies have suggested it plays a crucial role in maintaining systemic metabolic health. While these reports suggest a potential link between BAT and heart failure, the potential role of BAT dysfunction in heart failure has not been investigated. Here, we demonstrate that alteration of BAT function contributes to development of heart failure through disorientation in choline metabolism. Thoracic aortic constriction (TAC) or myocardial infarction (MI) reduced the thermogenic capacity of BAT in mice, leading to significant reduction of body temperature with cold exposure. BAT became hypoxic with TAC or MI, and hypoxic stress induced apoptosis of brown adipocytes. Enhancement of BAT function improved thermogenesis and cardiac function in TAC mice. Conversely, systolic function was impaired in a mouse model of genetic BAT dysfunction, in association with a low survival rate after TAC. Metabolomic analysis showed that reduced BAT thermogenesis was associated with elevation of plasma trimethylamine N-oxide (TMAO) levels. Administration of TMAO to mice led to significant reduction of phosphocreatine and ATP levels in cardiac tissue via suppression of mitochondrial complex IV activity. Genetic or pharmacological inhibition of flavin-containing monooxygenase reduced the plasma TMAO level in mice, and improved cardiac dysfunction in animals with left ventricular pressure overload. In patients with dilated cardiomyopathy, body temperature was low along with elevation of plasma choline and TMAO levels. These results suggest that maintenance of BAT homeostasis and reducing TMAO production could be potential next-generation therapies for heart failure.We thank Kaori Yoshida, Keiko Uchiyama, Satomi Kawai, Naomi Hatanaka, Yoko Sawaguchi, Runa Washio, Takako Ichihashi, Nanako Koike, Keiko Uchiyama, Masaaki Nameta (Niigata University), Kaori Igarashi, Kaori Saitoh, Keiko Endo, Hiroko Maki, Ayano Ueno, Maki Ohishi, Sanae Yamanaka, Noriko Kagata (Keio University) for their excellent technical assistance, C. Ronald Kahn (Joslin Diabetes Center and Harvard Medical School) for providing the BAT cell line, Evan Rosen (Harvard Medical School) for providing us Ucp-Cre mice, Kosuke Morikawa (Kyoto University), Tomitake Tsukihara (University of Hyogo) and Shinya Yoshikawa (University of Hyogo) for their professional opinions and suggestions. Tis work was supported by a Grant-in-Aid for Scientifc Research (A) (20H00533) from MEXT, AMED under Grant Numbers JP20ek0210114, and AMED-CREST under Grant Number JP20gm1110012, and Moonshot Research and Development Program (21zf0127003s0201), MEXT Supported Program for the Strategic Research Foundation at Private Universities Japan, Private University Research Branding Project, and Leading Initiative for Excellent Young Researchers, and grants from the Takeda Medical Research Foundation, the Vehicle Racing Commemorative Foundation, Ono Medical Research Foundation, and the Suzuken Memorial Foundation (to T.M.). Support was also provided by a Grants-in-Aid for Young Scientists (Start-up) (26893080), and grants from the Uehara Memorial Foundation, Kowa Life Science Foundation, Manpei Suzuki Diabetes Foundation, SENSHIN Medical Research Foundation, ONO Medical Research Foundation, Tsukada Grant for Niigata University Medical Research, Te Nakajima Foundation, SUZUKEN memorial foundation, HOKUTO Corporation, Mochida Memorial Foundation for Medical & Pharmaceutical Research, Grants-in-Aid for Encouragement of Young Scientists (A) (16H06244), Daiichi Sankyo Foundation of Life Science, AMED Project for Elucidating and Controlling Mechanisms of Aging and Longevity under Grant Number JP17gm5010002, JP18gm5010002, JP19gm5010002, JP20gm5010002, JP21gm5010002, Astellas Foundation for Research on Metabolic Disorders, Research grant from Naito Foundation, Te Japan Geriatrics Society (to I.S.); by a Grant-in-Aid for Scientifc Research (C) (19K08974), Yujin Memorial Grant, Sakakibara Memorial Research Grant from Te Japan Research Promotion Society for Cardiovascular Diseases, TERUMO Life Science Foundation, Kanae Foundation (to Y.Y.), JST ERATO (JPMJER1902), AMED-CREST (JP20gm1010009), the Takeda Science Foundation, the Food Science Institute Foundation (to S.F.), and by a grant from Bourbon (to T.M., I.S. and Y.Y.).S