Preparation and In Vitro Behavior of a Poly(lactic acid)-Fiber/Hydroxyapatite Composite Sheet

This paper describes the processing and in vitro behavior of a poly(lactic acid) (PLA)-fiber/hydroxyapatite (HA) composite sheet consisting of a knitted PLA-fiber sheet and HA powder for bone tissue engineering. Type I collagen was used as a binding agent to combine the PLA fibers and the HA powder. Precipitate formation in Hanks' balanced salt (HBS) solution was monitored to evaluate the in vitro apatite formation ability of the PLA-fiber/HA composite sheet. Precipitate formation was observed on the surface of the PLA-fiber/HA composite sheet after immersion in HBS solution for only 1 day, while no precipitate formation was observed on the PLA-fiber sheet without HA as a control. In conclusion, a PLA-fiber/HA composite sheet for use as a scaffold was successfully prepared. Within the limitations of this investigation, we confirmed that the PLA-fiber/HA composite sheet has a high apatite formation activity compared with the PLA-fiber sheet and represents a promising material for use as a scaffold

Characterization of Esthetic Orthodontic Wires Made from Glass-Fiber-Reinforced Thermoplastic Containing High-Strength, Small-Diameter Glass Fibers

In this work, we investigated the properties of a glass-fiber-reinforced thermoplastic (GFRTP) composed of small-diameter (ϕ = 5 μm), high-strength glass (T-glass) fibers and polycarbonate for esthetic orthodontic wires formed using pultrusion. After fabricating such GFRTP round wires, the effects of varying fiber diameter (5 to 13 mm) on the mechanical properties, durabilities, and color stabilities were evaluated. The results showed that the mechanical properties of GFRTPs tend to increase with decreasing fiber diameter. Additionally, it was confirmed that the present GFRTP wires containing T-glass fibers have better flexural properties than previously reported GFRTP wires containing E-glass fibers. Meanwhile, thermocycling did not significantly affect the flexural properties of the GFRTP wires. Furthermore, the GFRTP wires showed color changes lower than the acceptable threshold level for color differences on immersion in coffee. From these results obtained in the present work, the GFRTP wires containing high-strength glass fibers have excellent properties for orthodontic applications. Our findings suggest that the GFRTPs might be applied to all phases of orthodontic treatment because their properties can be tuned by changing the fiber properties such as fiber type and diameter

Gadd45β expression in chondrosarcoma: A pilot study for diagnostic and biological implications in histological grading

<p>Abstract</p> <p>Background</p> <p>Although the diagnosis of chondrosarcoma, especially the distinction between enchondroma and low-grade chondrosarcoma or low-grade chondrosarcoma and high-grade chondrosarcoma, is pathologically difficult, differential diagnosis is very important because the treatment strategies for these diseases are completely different. The grading system is crucial in predicting biologic behavior and prognosis, however, exact pathological grading is difficult using only routine examinations because the criteria of the grading system are not necessarily definitive. Growth arrest and DNA damage-inducible protein 45β (GADD45β) is an essential molecule for chondrocytes during terminal differentiation. In the present study, we investigated the immunohistochemical expression of GADD45β in enchondroma, and chondrosarcoma of histological grades I, II, and III, to clarify the diagnostic significance of GADD45β in pathological grading of chondrosarcoma.</p> <p>Methods</p> <p>Twenty samples (enchondroma = 6, chondrosarcoma grade I = 7, grade II = 6, grade III = 1) were used for immunohistochemical analysis to investigate the expression of GADD45β. Quantitative analysis was performed to compare the number of GADD45β positive cells and pathological grading.</p> <p>Results</p> <p>Over 70% of the cells in enchondromas expressed GADD45β. On the other hand, the expression of GADD45β decreased significantly according to the histological grade of chondrosarcoma (grade I: 45%; grade II: 13.8%; and grade III: 3.8%).</p> <p>Conclusions</p> <p>The association of GADD45β expression and pathological grading of chondrosarcoma in the present study suggests that the immunohistochemical study of GADD45β may be a specific diagnostic parameter for chondrosarcoma cell differentiation.</p

脂質代謝に関連した気管支喘息患者における白血球ロイコトリエン産生能に対するα-リノレン酸食の効果

Dietary sources of a -linolenic acid, such as perilla seed oil, may have the capacity to inhibit the generation of leukotrienes (LTs) by leucocytes in patients with asthma, as has been reported with the consumption of other long - chain n- 3 fatty a-cids. The factors affecting the suppression of leukotriene (LT) C4 generation by leucocytes were examined by comparing the clinical features of patients with asthma who had been given dietary perilla seed oil (n - 3 fatty acids). Group A consisted of patients in whom the leucocyte generation of dietary perilla seed oil LTC4 was suppressed by this procedure. Group B consisted of those in whom LTC4 generation was not suppressed. LTC4 generation by leucocytes significantly decreased in group A for two (P<0.05) and four weeks (P<O. OS), conversely, significantly increased in group B for four weeks (p<O. OS). The two study groups differed significantly in LTC4 generation by leucocytes after four weeks of dietary supplementation (P<0.05). Ventilatory parameters such as peak expiratory flow (PEF) , forced vital capacity (FVC) and forced expiratory volume in one second (FEV(1.O)) increased significantly after four weeks of dietary supplementation in group A (P<0.05). Values of PEF, FVC, FEV(1.O) and V(25) between groups A and B significantly differed prior to dietary supplementation. Serum levels of total cholesterol, LDL- cholesterol and phospholipid were significantly decreased by dietary supplementation in group A after four weeks. Serum levels of total-choles terol, triglyceride, HDL-Cholesterol, LDL-Cholesterol and phospholipid values between the two study groups differed significantly prior to dietary supplementation. Serum levels of triglyceride and LDL- cholesterol differed significantly between the two study groups after four weeks of dietary supplementation. The effects of dietary supplementation with perilla seed oil to patients with asthma by suppressing the generation of LTC4 is associated with clinical features such as respiratory function and lipometabolism.エゴマ油のようなα-リノレン酸食が他のn-3系不飽和脂肪酸食において報告されてきた様に喘息患者の白血球ロイコトリエン(LTs)産生能を抑制すると考えられる｡そこでエゴマ油(n-3系脂肪酸)を摂取した気管支喘息患者の臨床所見を比較することによって白血球ロイコトリエン(LT)C4の抑制に影響する因子を検討した。A群はエゴマ油摂取により白血球LTC4の産生能が抑制された群であり､B群は白血球LTC4の産生能が抑制されなかった群である｡A群では食事摂取2週後(P<0.05),4週後(P<0.05)に白血球LTC4産生能が低下した｡逆にB群では摂取4週後有意に増加した(P<0.05)0 2群間で食事摂取4遡後に白血球LTC4産生能に有意差がみられた(P<0.05)｡ピークフロー値(PEF)､努力性肺活量(FVC)､1秒量(FEV(1))といった呼吸機能はA群において食事摂取4週後に有意に上昇した(P<0.05)｡食事摂取前のPEF､FVC､FEV(1)､V(25)はA群,B群の2群間で有意差がみられた｡A群において血清総コレステロール､低比重リポ蛋白(LDL)コレステロール､リン脂質は食事摂取4週後に有意に低下した｡食事摂取前の血清総コレステロール､中性脂肪､高比重リポ蛋白コレステロール､LDLコレステロール､リン脂質において2群間に有意差がみられた｡血清中性脂肪､LDLコレステロールは食事摂取4週後2群間に有意差がみられた｡気管支喘息患者のある群へのエゴマ油食はLTC4産生能を抑制し､それには呼吸機能や脂質代謝といった臨床因子が関連していると考えられた

COVID-19: challenges faced by Nepalese migrants living in Japan

Worldwide, COVID-19 has exacerbated the vulnerability of migrants, impacting many facets of their lives. Nepalese make up one of the largest groups of migrants residing in Japan. Crises, such as the ongoing COVID-19 pandemic could disproportionately affect migrants from low- and middle-income countries like Nepal, widening health and economic inequalities. An in-depth, comprehensive assessment is needed to appraise the diverse problems they encounter. Drawing upon qualitative interviews, this study aimed to identify challenges faced by Nepalese migrants in Japan as a consequence of the COVID-19 pandemic and to discuss their needs to counter these challenges. This qualitative study employed an interpretivist approach to appraise the first-hand experience of Nepalese migrants living in Japan. Fourteen participants (8 males and 6 females, aged 21 to 47 years old) were recruited to participate in semi-structured in-depth telephone interviews (45–60 min) regarding: (a) their perceived current physical and mental health, (b) problems faced as a result of the COVID-19 pandemic, and (c) perception of available and necessary support structures. Purposive and snowball sampling techniques were used to recruit the participants. Interviews were recorded, transcribed, and thematically analyzed. Six themes were identified: 1) experiencing psychosomatic symptoms, 2) adoption of new healthy behaviors, 3) financial hardship, 4) family concerns, 5) reflections on discrimination and 6) reflections of existing support and expectations of support systems. The findings of our study illustrate the specific impact of COVID-19 among Nepalese migrants regarding their unstable employment conditions, perceived lack of social support, possible obligation to send money home, difficulty in accessing services due to the language barrier, and a lack of effective governmental support from Nepal. Pandemic-related adversity has negatively impacted migrants’ mental well-being, exacerbating their vulnerability. Comprehensive and timely support should be provided to the vulnerable migrant population. Effective coordination among relevant parties in both countries, including the governments concerned, should be facilitated.Institute of Medical Care and Societal Health, Japan

気管支喘息の low attenuation are (LAA) に対する長期喫煙の影響-4年間の経過観察-

Background-The influence of cigarette smoking on the pathogenesis of asthma in the elderly remains controversial. This study attempts to estimate longitudinal changes in HRCT (high resolution computed tomography) parameters and pulmonary function parameters obtained for ex-smokers and never-smokers in asthmatics during 4-yr follow-up period. Methods-Fourteen asthmatics (6 ex-smokers and 8 never-smokers) were studied to determine the influence of aging and cigarette smoking on pulmonary function, and mean lung density (MLD) and the relative area of the lung showing attenuation values less than -950 HU (RA950) on HRCT scans. Results-The values of FVC and FEV1, were significantly more decreased in asthmatics without a smoking history during 4-yr follow-up period. The values of FVC, FEV1, FEV1/FVC and DLco/VA were significantly decreased and RV/TLC were significantly increased in asthmatics with a smoking history over 4 years, and annual decline in FEV1 ex-smokers was larger than that in never-smokers. In the upper lung field, inspiratory MLD was observed to shift in a negative direction and inspiratory RA950 was found to increase during 4-yr observation period in ex-smokers, but not in never-smokers. In the middle lung field, inspiratory RA950 was significantly enhanced in both two groups. Although expiratory MLD, expiratory RA950 and exp RA950/ins RA950 were observed to change significantly during the observation period in ex-smokers, no changes were observed in never-smokers. Conclusion-These results suggest that aging augments airspace enlargement predominantly in the middle lung field, while long term cigarette smoking further worsens emphysematous alterations in the upper lung field.気管支喘息患者の肺高分解能CT所見に対する長期喫煙の影響を検討することを目的とした｡非喫煙喘息患者8名,喫煙歴を有する喘息患者6名を対象として,肺機能,肺平均CT値(MLD),-950HU以下のlow attenuation area(RA(950))について4年間の経過観察を行った｡ 4年間の観察中,非喫煙喘息患者では努力肺活量,1秒量の低下を認めた｡喫煙歴を有する喘息患者では努力肺活量,1秒量,1秒率,肺拡散能 の低下および残気率の増加を認めた｡喫煙歴を有する喘息患者では吸気において,上肺野MLDの有意の低下,RA(950)の有意の上昇を認めたが,非喫煙喘息患者では有意の変化は認めなかった｡中肺RA(950)は喫煙歴を有する喘息患者,非喫煙喘息患者ともに有意の上昇を認めた｡また,呼気において,喫煙歴を有する喘息患者でMLDの有意の低下,RA(950)の有意の上昇を認めたが,非喫煙喘息患者では有意の変化は認めなかった｡喘息患者において,加齢は主に中肺野のlow atenuation area,喫煙は上肺野のlow atenuation areaに影響を及ぼすことが示唆された

Current Status of the Development of a Transportable and Compact VLBI System by NICT and GSI

MARBLE (Multiple Antenna Radio-interferometer for Baseline Length Evaluation) is under development by NICT and GSI. The main part of MARBLE is a transportable VLBI system with a compact antenna. The aim of this system is to provide precise baseline length over about 10 km for calibrating baselines. The calibration baselines are used to check and validate surveying instruments such as GPS receiver and EDM (Electro-optical Distance Meter). It is necessary to examine the calibration baselines regularly to keep the quality of the validation. The VLBI technique can examine and evaluate the calibration baselines. On the other hand, the following roles are expected of a compact VLBI antenna in the VLBI2010 project. In order to achieve the challenging measurement precision of VLBI2010, it is well known that it is necessary to deal with the problem of thermal and gravitational deformation of the antenna. One promising approach may be connected-element interferometry between a compact antenna and a VLBI2010 antenna. By measuring repeatedly the baseline between the small stable antenna and the VLBI2010 antenna, the deformation of the primary antenna can be measured and the thermal and gravitational models of the primary antenna will be able to be constructed. We made two prototypes of a transportable and compact VLBI system from 2007 to 2009. We performed VLBI experiments using theses prototypes and got a baseline length between the two prototypes. The formal error of the measured baseline length was 2.7 mm. We expect that the baseline length error will be reduced by using a high-speed A/D sampler

Underestimation of COVID-19 cases in Japan: an analysis of RT-PCR testing for COVID-19 among 47 prefectures in Japan

Under the unique Japanese policy to restrict reverse transcriptase-polymerase chain reaction (RT-PCR) testing against severe acute respiratory syndrome coronavirus 2, a nationwide number of its confirmed cases and mortality remains to be low. Yet the information is lacking on geographical differences of these measures and their associated factors. Evaluation of prefecture-based geographical differences and associated predictors for the incidence and number of RT-PCR tests for COVID-19. Cross-sectional study using regression and correlation analysis. We retrieved domestic laboratory-confirmed cases, deaths, and the number of RT-PCR testing for COVID-19 from January 15 to April 6, 2020 in 47 prefectures in Japan, using publicly-available data by the Ministry of Health, Labour and Welfare. We did descriptive analyses of these three measures and identified significant predictors for the incidence and RT-PCR testing through multiple regression analyses and correlates with the number of deaths through correlation analysis. The median prefectural-level incidence and number of RT-PCR testing per 100,000 population were 1.14 and 38.6, respectively. Multiple regression analyses revealed that significant predictors for the incidence were prefectural-level population (p < 0.001) and the number of RT-PCR testing (p = 0.03); and those for RT-PCR testing were the incidence (p = 0.025), available beds (p = 0.045) and cluster infections (p = 0.034). Considering bidirectional association between the incidence and RT-PCR testing, there may have been an underdiagnosed population for the infection. The restraint policy for RT-PCR testing should be revisited to meet the increasing demand under the COVID-19 epidemic.N/