Evaluation of muscle strength and its relation to exercise habits in Japanese

The aim of this study was to explore muscle strength and its relation to exercise habits in Japanese. We used data from 3,018 men and 6,881 women aged 20-69 years and not using medications in a cross-sectional study. Exercise habits and muscle strength, i.e. grip strength and leg strength, were measured. Age-related changes in muscle strength were noted. Exercise habits were found in 984 men (32.6%) and 1,664 women (24.2%). For subjects of both sexes over 50 years, grip strength was significantly decreased with age. However, the ratio of leg strength to body weight significantly decreased with age as early as 30 years in men and 40 years in women. Grip strength, leg strength and the ratio of leg strength to body weight in subjects with exercise habits were significantly higher than those without exercise habits after adjusting for age in both sexes. This standard mean value may provide a useful database for evaluating muscle strength in Japanese adult subjects.</p

Bumping algorithm for set-valued shifted tableaux

We present an insertion algorithm of Robinson–Schensted type that applies to set-valued shifted Young tableaux. Our algorithm is a generalization of both set-valued non-shifted tableaux by Buch and non set-valued shifted tableaux by Worley and Sagan. As an application, we obtain a Pieri rule for a K-theoretic analogue of the Schur Q-functions

Relationship between peak oxygen uptake and regional body composition in Japanese subjects

AbstractPurposeTo investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects.MethodsA total of 93 men (42.2 ± 12.3 years old) and 106 women (43.5 ± 12.3 years old) were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated.ResultsPeak oxygen uptake was 37.6 ± 8.7 mL/kg/min in men and 31.1 ± 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage (men: r = −0.684, p < 0.0001; women: r = −0.681, p < 0.0001). These associations remained even after adjusting for age and total lean body mass. However, peak work rate was positively and significantly correlated with leg lean body mass.ConclusionPeak oxygen uptake was closely correlated with total body fat percentage in both genders. Aerobic exercise as well as leg resistance training might be useful for improving peak oxygen uptake in Japanese subjects

Comparison of muscle strength between Japanese men with and without metabolic syndrome

We compared muscle strength between Japanese men with and without metabolic syndrome. We used data for 323 Japanese men with metabolic syndrome and 893 Japanese men without the syndrome. Metabolic syndrome was defined by a new criterion in Japan, and the parameters for muscle strength, i.e. grip strength, leg strength were measured. Leg strength was found to be significantly higher in subjects with metabolic syndrome than in those without, while muscle strength per body weight was significantly lower in subjects with the syndrome. Lower muscle strength per body weight may be one of the characteristic features in subjects with metabolic syndrome.</p

Mitochondrial movement during its association with chloroplasts in Arabidopsis thaliana

葉緑体との相互作用におけるミトコンドリア運動を発見 --相互作用の制御による効率的な物質代謝の可能性に期待--. 京都大学プレスリリース. 2021-03-19.Plant mitochondria move dynamically inside cells and this movement is classified into two types: directional movement, in which mitochondria travel long distances, and wiggling, in which mitochondria travel short distances. However, the underlying mechanisms and roles of both types of mitochondrial movement, especially wiggling, remain to be determined. Here, we used confocal laser-scanning microscopy to quantitatively characterize mitochondrial movement (rate and trajectory) in Arabidopsis thaliana mesophyll cells. Directional movement leading to long-distance migration occurred at high speed with a low angle-change rate, whereas wiggling leading to short-distance migration occurred at low speed with a high angle-change rate. The mean square displacement (MSD) analysis could separate these two movements. Directional movement was dependent on filamentous actin (F-actin), whereas mitochondrial wiggling was not, but slightly influenced by F-actin. In mesophyll cells, mitochondria could migrate by wiggling, and most of these mitochondria associated with chloroplasts. Thus, mitochondria migrate via F-actin-independent wiggling under the influence of F-actin during their association with chloroplasts in Arabidopsis

Case Report Common Peroneal Nerve Palsy with Multiple-Ligament Knee Injury and Distal Avulsion of the Biceps Femoris Tendon

A multiple-ligament knee injury that includes posterolateral corner (PLC) disruption often causes palsy of the common peroneal nerve (CPN), which occurs in 44% of cases with PLC injury and biceps femoris tendon rupture or avulsion of the fibular head. Approximately half of these cases do not show functional recovery. This case report aims to present a criteria-based approach to the operation and postoperative management of CPN palsy that resulted from a multiple-ligament knee injury in a 22-year-old man that occurred during judo. We performed a two-staged surgery. The first stage was to repair the injuries to the PLC and biceps femoris. The second stage involved anterior cruciate ligament reconstruction. The outcomes were excellent, with a stable knee, excellent range of motion, and improvement in the palsy. The patient was able to return to judo competition 27 weeks after the injury. To the best of our knowledge, this is the first case report describing a return to sports following CPN palsy with multiple-ligament knee injury

Ultrasonography imaging of the anterolateral ligament using real-time virtual sonography

Background: The anterolateral ligament (ALL) functions as a stabilizer in the internal rotation of the knee. Previous studies have reported the ALL can be identified using magnetic resonance imaging (MRI); however, there are no reports on using ultrasonography (US) for this purpose. Real-time virtual sonography (RVS) uses magnetic navigation and computer software for the synchronized display of real-time US and multiplanar reconstruction MRI images. This study investigated the ability of using US with RVS to evaluate the ALL. Methods: Nine healthy subjects were enrolled. The Digital Imaging Communications in Medicine MRI dataset was loaded into the Hitachi Aloka Preirus, and US images were displayed on the same monitor. When the ALL was identified using MRI, the monitor was frozen to evaluate the ALL. The ALL was divided into the femoral, meniscal, and tibial portions. The portions and thickness of the ALLs and the lateral inferior genicular artery (LIGA), a landmark for the ALL, were evaluated. Results: All portions of the ALL could be identified using MRI. Using US, the tibial portion of the ALL was detected in all subjects and the femoral portion was detected in seven subjects; however, the meniscal portions could not be identified. The average ALL thickness as measured by US was 1.3 ± 0.1 mm and the LIGA was identified in all cases. Conclusions: Most portions of the ALL can be identified using US. As most ALL injuries occur at the femoral or tibial portion, US may be useful as a diagnostic tool for ALL injury.Level of Evidence: 4. © 2015 Elsevier B.V.Embargo Period 12 month

Linkage between Oxygen Uptake at Ventilatory Threshold and Muscle Strength in Subjects with and without Metabolic Syndrome

We evaluated the linkage between oxygen uptake at the ventilatory threshold (VT) and muscle strength in subjects with and without metabolic syndrome. We used data of 226 Japanese men with metabolic syndrome and 265 Japanese men without the syndrome. Metabolic syndrome has recently been defined by a new criterion in Japan. Oxygen uptake at VT and muscle strength, i.e. grip strength and leg strength were measured. Oxygen uptake at VT and muscle strength/body weight were found to be significantly lower in subjects with metabolic syndrome than in those without the syndrome. However, the differences did not reach significant levels after adjusting for leg strength/body weight or oxygen uptake at VT. A combination of aerobic exercise and resistance training might be considered for preventing and improving metabolic syndrome.</p

Precise risk factors for Osgood–Schlatter disease

Introduction: A number of studies have examined the risk factors for Osgood–Schlatter disease (OSD). Studies on risk factors have not necessarily accurately demonstrated the risk factors of this disease because they were not prospective cohort studies or the populations in the studies were not categorized by the skeletal maturation of the tibial tuberosity. We can identify the precise risk factors for OSD by performing a prospective cohort study of a group of asymptomatic patients in particular times of adolescent using ultrasonography. In the present study, we aimed to investigate the precise risk factors for OSD. Methods: For all examinations, we used a 3-stage classification for tibial tuberosity development observed on ultrasonography: sonolucent (stage S), individual (stage I), and connective stages (stage C). Among 150 players with 300 knees, we included 37 male players with 70 knees at asymptomatic stage I on the first examination. We re-examined the included knees 1 year after the first examination and compared 10 knees with OSD (OSD group) and 60 knees without OSD (control group). Height, body weight, body mass index, tightness of the quadriceps femoris and hamstring muscles, muscle strength during knee extension, and flexion were assessed during the first medical examination. Results: The incidence of OSD was 14.3 % in this 1-year cohort study. A significant difference was found in body weight, quadriceps muscle tightness, and muscle tightness and strength during knee extension between the 2 groups. The precise risk factors for OSD were increased, namely the quadriceps femoris muscle tightness and strength during knee extension and flexibility of the hamstring muscles, using logistic regression analysis. Conclusions: This information may be useful for teaching quadriceps stretching in preadolescent male football players with stage I. © 2015 Springer-Verlag Berlin Heidelber

Technique of anatomical single bundle ACL reconstruction with rounded rectangle femoral dilator

Background: This study aimed to present a new technique for anatomical single bundle anterior cruciate ligament (ACL) reconstruction. We developed an original rounded rectangular dilator set to create rounded rectangular femoral tunnels. This technique can increase the femoral tunnel size without roof impingement, and has the potential to reduce the graft failure rate. We investigated the tunnel position and the incidence of intraoperative complications. Method: The presented technique is anatomical single bundle ACL reconstruction using a semitendinosus graft (with or without the gracilis tendon). The tunnel was drilled via an additional medial portal. Rounded rectangular tunnels were created using a special dilator. Tibial tunnels were created using conventional rounded tunnels. Fixation was achieved using a suspensory device on the femoral side and a plate and screw on the tibial side. Patients: Fifty patients underwent this surgery, and intraoperative complications were investigated. The femoral tunnel positions were documented postoperatively from computed tomography scans using the quadrant method. The tibial tunnel positions (anterior-to-posterior, medial-to-lateral) were documented using intraoperative X-ray scans. Results: Only one patient had a partial posterior tunnel wall blowout. The femoral tunnel length varied between 30 and 40 mm (mean, 34.9 ± 3.3 mm). All femoral and tibial tunnels were located within the area of the anatomical ACL insertions. Conclusion: We did not experience any serious intraoperative complications during anatomical single bundle ACL reconstruction using a rounded rectangle dilator, and the resulting locations of the femoral and tibial tunnels were within the anatomical ACL footprint. Level of evidence: Level IV. © 2015 Elsevier B.V..Embargo Period 12 month