Explore the vast range of titles available.

Forward head posture (FHP) is a serious problem causing head and neck disability, but the characteristics of muscle activity during long-term postural maintenance are unclear. This study aimed to investigate a comparison of electromyography (EMG) activation properties and subjective fatigue between young adults with and without habitual FHP. In this study, we examined the changes in the spatial and temporal distribution patterns of muscle activity using high-density surface EMG (HD-SEMG) in addition to mean frequency, a conventional measure of muscle fatigue. Nineteen male participants were included in the study (FHP group (n = 9; age = 22.3 ± 1.5 years) and normal group (n = 10; age = 22.5 ± 1.4 years)). Participants held three head positions (e.g., forward, backward, and neutral positions) for a total of 30 min each, and the EMG activity of the trapezius pars descendens muscle during posture maintenance was measured by HD-SEMG. The root mean square (RMS), the modified entropy, and the correlation coefficient were calculated. Additionally, the visual analogue scale (VAS) was evaluated to assess subjective fatigue. The RMS, VAS, modified entropy, and correlation coefficients were significantly higher in the FHP group than in the normal group ( p  < 0.001). With increasing postural maintenance time, the modified entropy and correlation coefficient values significantly decreased, and the mean frequency and VAS values significantly increased ( p  < 0.001). Furthermore, the forward position had significantly higher RMS, correlation coefficient, modified entropy, and VAS values than in the neutral position ( p  < 0.001). The HD-SEMG potential distribution patterns in the FHP group showed less heterogeneity and greater muscle activity in the entire muscle and subjective fatigue than those in the normal group. Excess muscle activity even in the neutral/comfortable position in the FHP group could potentially be a mechanism of neuromuscular conditions in this population.

Metal-based powder bed fusion with a laser beam (PBF-LB/M) can be applied to fabricate high-accuracy structures compared with other metal additive manufacturing (AM) methods. The rapid solidification of metal powder formed by laser irradiation introduces heterogeneous residual stress, which causes deformation and cracking of the structure. This, in turn, results in the deterioration of quality. In this study, the influence of the laser scan strategy on the residual stress distribution and warpage of the structure was investigated. Using maraging steel powder with an average particle size of 32.5 μm, the structures were constructed using several laser scan strategies at a wavelength of 1070 nm. The residual stress distributions on the surface of the structures were measured by the cosα method by applying X-ray diffraction (XRD). In addition, the warpage of the reverse side of the substrate as a foundation of the structure was measured by a stylus-type surface roughness measuring instrument. The results clarified that the structures constructed by unidirectional scan directions had a tensile residual stress that was generated parallel to the laser scan direction. Meanwhile, the compressive residual stress was generated perpendicular to the laser scan direction. The large warpage was aligned with the laser scan direction and tensile residual stress. When the laser scan direction was rotated by 90° for each layer, the residual stress distribution was generated with a cruciform shape. It was indicated that this residual distribution was caused by a laser scan on the top surface and a lower layer. The anisotropic residual stress distribution and reduction of warpage could be corrected by rotating the laser scan direction by 15° in each layer.

Background Finite element analysis (FEA) has been previously applied for the biomechanical analysis of acetabular dysplasia and osteotomy. However, until now, there have been little reports on the use of FEA to evaluate the effects of pelvic tilt on stress distribution in the acetabulum. Methods We used the Mechanical Finder Ver. 7.0 (RCCM, Inc., Japan) to construct finite element models based on 3D-CT data of patients, and designed dysplasia, borderline, and normal pelvic models. For analysis, body weight was placed on the sacrum and the load of the flexor muscles of the hip joint was placed on the ilium. The pelvic tilt was based on the anterior pelvic plane, and the pelvic tilt angles were -20°, 0°, and 20°. The load of the flexor muscle of the hip joint was calculated using the moment arm equation. Results All three models showed the highest values of von Mises stress in the -20° pelvic tilt angle, and the lowest in the 20° angle. Stress distribution concentrated in the load-bearing area. The maximum values of von Mises stress in the borderline at pelvic tilt angles of -20° was 3.5Mpa, and in the dysplasia at pelvic tilt angles of 0° was 3.1Mpa. Conclusions The pelvic tilt angle of -20° of the borderline model showed equal maximum values of von Mises stress than the dysplasia model of pelvic tilt angle of 0°, indicating that pelvic retroversion of -20° in borderline is a risk factor for osteoarthritis of the hip joints, similar to dysplasia.

There is a paucity of data on management strategies and clinical outcomes after recurrent venous thromboembolism (VTE). In a multicenter registry enrolling 3027 patients with acute symptomatic VTE, the current study population was divided into the following 3 groups: (1) First recurrent VTE during anticoagulation therapy (N = 110); (2) First recurrent VTE after discontinuation of anticoagulation therapy (N = 116); and (3) No recurrent VTE (N = 2801). Patients with first recurrent VTE during anticoagulation therapy more often had active cancer (45, 25 and 22%, P < 0.001). Among 110 patients with first recurrent VTE during anticoagulation therapy, 84 patients (76%) received warfarin at recurrent VTE with the median prothrombin time-international normalized ratio (PT-INR) value at recurrent VTE of 1.6, although patients with active cancer had a significantly higher median PT-INR value at recurrent VTE compared with those without active cancer (2.0 versus 1.4, P < 0.001). Within 90 days after recurrent VTE, 23 patients (20.9%) during anticoagulation therapy and 24 patients (20.7%) after discontinuation of anticoagulation therapy died. Active cancer was a major cause of recurrent VTE during anticoagulation therapy as a patient-related factor, while sub-optimal intensity of anticoagulation therapy was a major cause of recurrent VTE during anticoagulation therapy as a treatment-related factor, particularly in patients without active cancer.

Several studies have reported a correlation between right ventricular (RV) and left ventricular (LV) systolic dysfunction in adults with repaired tetralogy of Fallot (TOF). However, data are lacking regarding the relationship between RV and LV diastolic dysfunction assessed by 2-dimensional speckle-tracking echocardiography. We studied 69 adults with repaired TOF (mean age 34 years, 61% male) who had been regularly followed up and had routinely undergone echocardiography. In addition to conventional echocardiography, global longitudinal strain (GLS) and early diastolic strain rate (SRe) of both ventricles were assessed using 2-dimensional speckle-tracking echocardiography. Results were compared with 30 age- and sex-matched controls. RV and LV GLS were decreased in TOF patients compared with controls (− 18.4 ± 3.3% vs. −23.5 ± 4.2%, p < 0.001 and − 16.0 ± 3.8% vs. −20.0 ± 3.0%, p < 0.001, respectively). RV and LV SRe were also decreased in TOF patients compared with controls (1.22 ± 0.34 sec− 1 vs. 1.47 ± 0.41 sec− 1, p = 0.003 and 1.29 ± 0.42 sec− 1 vs. 1.63 ± 0.42 sec− 1, p < 0.001, respectively). A correlation between RV and LV SRe was found in TOF patients (r = 0.43, p < 0.001) as well as between RV and LV GLS (r = 0.45, p < 0.001). Two-dimensional speckle-tracking echocardiography reveals subclinical RV and LV diastolic dysfunction in adults with repaired TOF. A correlation is observed between RV and LV diastolic dysfunction as well as between RV and LV systolic dysfunction.

When designing a large-sized cast product for a multi-spindled machine tool, such as a multi-turret type multi-tasking machine, we must first determine its thermal deformations by the finite element method (FEM) in order to ensure that the structure is designed with high thermal rigidity. Casting technology has progressed so much that we can now form more complicated internal structures and produce much thinner and lighter cast products. Moreover, since designing cast products has become much faster, higher-efficiency analytical techniques are also required. Such analytical techniques are operated by designers where analyses and design are executed interchangeably. In this study, we compared the experimental results to the analytical results in order to evaluate the employed analytical technique based on an actual analysis of a multi-tasking machine bed with a few different rib structures.

Statins, which are considered as essential for primary and secondary prevention of atherosclerotic diseases, were also reported to reduce first venous thromboembolism (VTE). However, the effect of statins on VTE recurrence remains conflicting. We aimed to examine the association between statin use and VTE recurrence in a large observational study in Japan. The COMMAND VTE Registry is a multicenter registry enrolling consecutive 3027 patients with acute symptomatic VTE in 29 centers in Japan between January 2010 and August 2014. In the current study, the entire cohort was divided into statin group (N = 437) and no-statin group (N = 2590) according to the status of statin use at baseline. The statin group as compared with the no-statin group was older (statin group 71.2 vs no-statin group 66.5 years, p <0.001), included more women (67% vs 60%, p = 0.008), and less frequently had active cancer (12% vs 25%, p <0.001). There was no significant difference in the clinical presentation of VTE (pulmonary embolism, 58% vs 56%, p = 0.44). The cumulative 3-year incidence of recurrent VTE was significantly lower in the statin group than the no-statin group (3.8% vs 8.8%, p <0.001). After adjusting for confounders including active cancer, statin use was associated with significantly lower risk for recurrent VTE (Hazard ratio 0.49, 95% confidence interval 0.29 to 0.78, p = 0.002). The results were consistent in a sensitivity sub-group analysis with and without active cancer. In conclusion, statin use was associated with significantly lower risk for the recurrent VTE in patients with VTE.

Immune light-chain (AL) amyloidosis with cardiac involvement is associated with a high mortality despite improved therapeutic regimens, but there are few reports on prognostic predictors and chronological changes in cardiac morphology and function. Prognosis and its predictors were evaluated in 36 consecutive patients with cardiac AL amyloidosis. Chronological changes in cardiac morphology and function were also evaluated. The median follow-up period was 0.95 years. The median survival time and the 3-year death-free rate after diagnosis in all-cause and cardiac deaths were 0.85 and 1.06 years and 26% and 36%, respectively. Differences in the median survival time due to left ventricular (LV) wall thickness at diagnosis were not evident. Being female and diastolic wall strain (DWS), as a measure of diastolic stiffness, were independent predictors of all-cause death in the multivariable analysis. The receiver operating characteristic analysis revealed that a DWS cut-off value of 0.189 had a sensitivity of 78% and a specificity of 72% for predicting all-cause death within 1 year after diagnosis (area under the curve = 0.726). The LV size and the stroke volume decreased and DWS worsened during the short-term follow-up period in patients who died within 1 year compared with patients who were alive after 1 year. The prognosis for patients with cardiac AL amyloidosis was poor, and DWS may be a significant predictor of prognosis. Narrowing of the LV cavity and progressive diastolic dysfunction were evident in patients with a poor prognosis.

Prolonged anticoagulation therapy is recommended for patients with intermediate-risk for recurrence of venous thromboembolism (VTE). The current study aimed to identify risk factors of VTE recurrence and major bleeding in intermediate-risk patients. The COMMAND VTE Registry is a multicenter registry enrolled consecutive 3027 patients with acute symptomatic VTE among 29 centers in Japan. The current study population consisted of 1703 patients with intermediate-risk for recurrence. The primary outcome measure was recurrent VTE during the entire follow-up period, and the secondary outcome measures were recurrent VTE and major bleeding during anticoagulation therapy. In the multivariable Cox regression model for recurrent VTE incorporating the status of anticoagulation therapy as a time-updated covariate, off-anticoagulation therapy was strongly associated with an increased risk for recurrent VTE (HR 9.42, 95% CI 5.97–14.86). During anticoagulation therapy, the independent risk factor for recurrent VTE was thrombophilia (HR 3.58, 95% CI 1.56–7.50), while the independent risk factors for major bleeding were age ≥ 75 years (HR 2.04, 95% CI 1.36–3.07), men (HR 1.52, 95% CI 1.02–2.27), history of major bleeding (HR 3.48, 95% CI 1.82–6.14) and thrombocytopenia (HR 3.73, 95% CI 2.04–6.37). Among VTE patients with intermediate-risk for recurrence, discontinuation of anticoagulation therapy was a very strong independent risk factor of recurrence during the entire follow-up period. The independent risk factors of recurrent VTE and those of major bleeding during anticoagulation therapy were different: thrombophilia for recurrent VTE, and advanced age, men, history of major bleeding, and thrombocytopenia for major bleeding.Clinical Trial RegistrationUnique identifier: UMIN000021132. COMMAND VTE Registry: http://www.umin.ac.jp/ctr/index.htm.

Background Extracorporeal membrane oxygenation (ECMO) might be required as a treatment option in patients with critical pulmonary embolism (PE). However, the clinical features and outcomes of the use of ECMO for critical acute PE are still limited. The present study aimed to clarify the clinical characteristics, management strategies and outcomes of patients with acute PE requiring ECMO in the current era using data from a large-scale observational database. Methods We analyzed the data of the COMMAND VTE Registry-2: a physician-initiated, multicenter, retrospective cohort study enrolling consecutive patients with acute symptomatic venous thromboembolism (VTE). Among 2035 patients with acute symptomatic PE, there were 76 patients (3.7%) requiring ECMO. Results Overall, the mean age was 58.4 years, and 34 patients (44.7%) were men. Cardiac arrest or circulatory collapse at diagnosis was reported in 67 patients (88.2%). The 30-day incidence of all-cause death was 30.3%, which were all PE-related deaths. The 30-day incidence of major bleeding was 54.0%, and the vast majority of bleedings were procedure site-related bleeding events and surgery-related bleeding (22.4%). The 30-day incidence of all-cause death was 6.3% in 16 patients with surgical intervention, 43.8% in 16 patients with catheter intervention, 25.0% in 16 patients with thrombolytic therapy, and 39.3% in 28 patients with anticoagulation only. Conclusions The current large real-world VTE registry in Japan revealed clinical features and outcomes of critical acute PE requiring ECMO in the current era, which suggested several unmet needs for future clinical trials.