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Background: Knee is the most commonly injured part of the body in young athletes. Knee pain in several studies have been seen to be more prevalent in active adolescents compared to inactive, although common in both groups. Nevertheless, few studies with large sample size have been published reporting the difference of the prevalence of knee pain for each sport among young sports players. This study investigated the point prevalence of knee pain among young sports players aged 6-15 years old according to age, sex, and sports discipline. Furthermore, this study investigated the association between knee pain and sports discipline among young sports players., Methods: A cross-sectional study was conducted using a self-reported questionnaire on young sports players aged 6-15 years from the Miyagi Amateur Sports Association. Multivariable logistic regression models were used to examine the association between knee pain and sports discipline and were adjusted for age, sex, body mass index (BMI), training days per week, and training hours per weekday and weekend., Results: A total of 7234 young sports players were included. The point prevalence of knee pain was 10.9%. Females (13.3%) had more knee pain than males (9.8%). Young, 13-year-old sports players had the highest prevalence of knee pain (19.1%). The multivariable analysis showed that the highest odds ratio [95% confidence interval] was observed for handball players (2.42 [1.01-5.81]). In addition, hand ball, mini-basketball (odds ratio 1.85; 95% CI 1.38-2.47), and basketball (odds ratio 1.66; 95% CI 1.23-2.26) were significantly associated with knee pain, compared with football. The lowest odds ratio was observed for swimming (0.34 [0.05-2.54]), followed by karate (odds ratio 0.38; 95% CI 0.16-0.89) and baseball (odds ratio 0.47; 95% CI 0.35-0.64)., Conclusion: The prevalence of knee pain among young athletes differed according to age, sex, and sports discipline. Their parents and clinicians should recognize this information to manage knee pain among young sports players., (© 2023. The Author(s).)

Myoblast integrity is essential for skeletal muscle regeneration. Many intracellular proteins are degraded by the proteasome and converted to amino acids by aminopeptidases through the protein degradation pathway. Although we previously reported its importance for myoblast integrity, the involved mechanism remains unclear. In this study, we focused on the reusability of proteolytic products to elucidate the regulatory mechanism of protein synthesis mediated by the proteasome and aminopeptidases. Proteasome inhibition decreased protein synthesis, but recycled-amino acids derived from proteasomal proteolysis were not reused for de novo protein synthesis in C2C12 myoblasts. On the other hand, proteasome and aminopeptidase inhibition decreased intracellular ATP levels in C2C12 myoblasts. Therefore, it was indicated that amino acids produced by these proteolytic systems may be reutilized for ATP production through its metabolism, not for de novo protein synthesis. These findings suggested the proteasome and aminopeptidases are thought to be involved in protein synthesis through intracellular energy production by recycled-amino acid metabolism, thereby maintaining myoblast integrity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Bruxism is defined as a repetitive masticatory muscle activity, characterized by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. Although the bruxism etiology can be bidirectionally described with sleep disorders, there are few studies available to understand the association of sleep duration with bruxism behavior in early childhood., Methods: A dataset of children (n = 90,148) from the Japan Environment and Children's Study (JECS) - an ongoing nationwide, prospective birth cohort study - was used to investigate the prospective association of the infant's sleep duration with bruxism behavior, which were acquired using self-reported questionnaire. After multiple imputation of data, the association between sleep duration and bruxism behavior in early childhood was examined using a binomial logistic regression analysis. It was conducted with adjustments for several maternal (e.g., age at delivery and sleep duration) and child-related (e.g., sex and sleep position) variables., Results: The prevalence of bruxism behavior at the ages of two and four were 16.2% and 22.5%, respectively. Using the shortest sleep duration group's participants (≤13 h) as the reference, the odds ratio (95% confidence interval) for prevalence of bruxism behavior decreased with longer sleep duration at one month of age, but not at 36 months of age, after covariate adjustments. Furthermore, in comparison with the impacts between daytime and nighttime sleep, nighttime sleep with longer duration were dominantly associated with bruxism behavior., Conclusion: The sleep duration in infant stage, especially during newborn stage was associated with the prevalence of bruxism behavior in children., Competing Interests: Declaration of competing interest No potential conflict of interest was reported by the authors., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Patients undergoing unilateral orthopedic or neurological rehabilitation have different levels of impairments in the right- or left-dominant hand. However, how handedness and the complexity of the motor task affect motor skill acquisition and its interlimb transfer remains unknown. In the present study, participants performed finger key presses on a numeric keypad at 4 levels of sequence complexities with each hand in a randomized order. Furthermore, they also performed motor sequence practice with the dominant hand to determine its effect on accuracy, reaction time, and movement time. The NASA-TLX at the end of each block of both testing and practice was used to confirm participants' mental workload related to sequence complexity. Both right- and left-handed participants performed the motor sequence task with faster RT when using their right hand. Although participants had increasing RT with increasing sequence complexity, this association was unrelated to handedness. Motor sequence practice produced motor skill acquisition and interlimb transfer indicated by a decreased RT, however, these changes were independent of handedness. Higher sequence complexity was still associated with longer RT after the practice, moreover, both right- and left-handed participants' RT increased with the same magnitude with the increase in sequence complexity. Similar behavioral pattern was observed in MT as in RT. Overall, our RT results may indicate left-hemisphere specialization for motor sequencing tasks, however, neuroimaging studies are needed to support these findings. On the other hand, handedness did not affect motor skill acquisition by the dominant hand or interlimb transfer to the non-dominant hand regardless of task complexity level., (© 2022. The Author(s).)

We examined the effects of side-dominance on the laterality of standing stability using ground reaction force, motion capture ( MoCap ), and EMG data in healthy young adults. We recruited participants with strong right ( n = 15) and left ( n = 9) hand and leg dominance (side-dominance). They stood on one or two legs on a pair of synchronized force platforms for 50 s with 60 s rest between three randomized stance trials. In addition to 23 CoP -related variables, we also computed six MoCap variables representing each lower-limb joint motion time series. Moreover, 39 time- and frequency-domain features of EMG data from five muscles in three muscle groups were analyzed. Data from the multitude of biosignals converged and revealed concordant patterns: no differences occurred between left- and right-side dominant participants in kinetic, kinematic, or EMG outcomes during bipedal stance. Regarding single leg stance, larger knee but lower ankle joint kinematic values appeared in left vs right-sided participants during non-dominant stance. Left-vs right-sided participants also had lower medial gastrocnemius EMG activation during non-dominant stance. While right-side dominant participants always produced larger values for kinematic data of ankle joint and medial gastrocnemius EMG activation during non-dominant vs dominant unilateral stance, this pattern was the opposite for left-sided participants, showing larger values when standing on their dominant vs non-dominant leg, i.e., participants had a more stable balance when standing on their right leg. Our results suggest that side-dominance affects biomechanical and neuromuscular control strategies during unilateral standing., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Négyesi, Petró, Salman, Khandoker, Katona, Wang, Almaazmi, Hortobágyi, Váczi, Rácz, Pálya, Grand, Kiss and Nagatomi.)

Background: There is a need to develop strategies that could contribute to the physical and mental preparation of motorsport athletes. A common method used by experienced motorsport athlete physical trainers is flashing light devices to train or assess reactive agility, despite limited evidence. Therefore, in the present study, we determined the effects of a 6-week reactive agility training program using light-based stimuli on the physiological and cognitive abilities of car racing drivers., Materials and Methods: The CONSORT guidelines for randomized controlled trial were used. In a single-blinded randomized controlled trial, 24 car racing drivers (EXP, n = 12; CON, n = 12) performed a comprehensive battery of cognitive tests marketed specifically at motorsport athletes from Vienna test system (VTS) at rest or during moderate intensity exercise on a bicycle. Physiological abilities were determined via a maximal incremental cardio-respiratory treadmill test. Baseline and post-intervention tests were performed on three consecutive days. Participants in EXP underwent a 6-week intervention consisting of 60-min training sessions twice a week using the Witty SEM light stimulus., Results: Participants in EXP but not in CON performed some of the VTS cognitive tasks with higher accuracy and/or shorter reaction time after the intervention at rest and during exercise. Car racing drivers performed the STROOP word-reading condition more accurately when the task was performed during the exercise vs. rest, regardless of group. In addition, the intervention induced beneficial changes in peak heart rate (HR), HR at gas exchange threshold, ventilation, and relative maximal oxygen consumption (rVO 2 max). In contrast, body mass and fat mass increased, while peak HR and rVO 2 max decreased in CON. Finally, participants in EXP improved their reactive agility performance and reaction time throughout the training program., Conclusion: Overall, the reactive agility training program using light-based stimuli appeared to be efficient to induce beneficial effects on some physiological and cognitive performance measures; therefore, it may have the potential to contribute to car racing drivers' physical and mental performance., (© 2022. The Author(s).)

Purpose: Task complexity could affect acquisition efficiency of motor skills and interlimb transfer; however, how task complexity affects interlimb transfer remains unclear. We hypothesized that left- and right-handed participants may have different interlimb transfer efficiency depending on the task complexity., Methods: Left-hand (n = 28) and right-hand (n = 28) dominant participants (age = 24.70 ± 4.02 years, male:female = 28:28) performed a finger sequence test with two levels of complexity (simple: one-digit with four fingers vs. complex: two-digit with five fingers) before and after ten trials of 2-min practice each on the same apparatus. The speed and task errors were measured and analyzed., Results: Right-handed participants failed to improve performance on their right hand (non-trained hand) after contralateral left-hand practice in the simple finger sequence task. In contrast, the left-handed participants improved performance on non-trained hands both right and left after contralateral practices. In the complex task, however, both the left- and right-handed participants improved performance on non-trained hands by contralateral practices., Conclusion: Our results showed that task complexity of skilled practice gave different effects on interlimb transfer between right- and left-handed subjects. It appears that a certain level of appropriate complexity is necessary to detect inter-limb transfers in motor learning in right-handed subjects., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objectives: Daily toothbrushing behaviour is very effective for the prevention of early childhood dental caries (ECC), but is mostly dependent upon parental management. Intrapersonal association between lower toothbrushing frequency and depression is well known; however, the impact of maternal postpartum depression on child toothbrushing behaviour within the mother-child dyad remains unknown. The aim of this study was to determine the association between the prevalence of maternal postpartum depression and lower toothbrushing frequency in children aged two years., Methods: A secondary analysis of a data set from the Japan Environment and Children's Study was performed. A total of 104 062 fetuses were enrolled after obtaining informed written parental consent, in which 84 533 mother-infant pairs were included after applying exclusion criteria. The Edinburgh Postpartum Depression Scale (EPDS) was used to evaluate maternal postpartum depression (a total score of ≥9 in EPDS) at one and six months postpartum. Indeed, the participants were classified based on the persistence of postpartum depression: 'Resilient' (no prevalence); 'Improving' (prevalence only at one month postpartum); 'Emergent' (prevalence only at six months postpartum); and 'Chronic' (prevalence at both time points). The association between postpartum depression and a toothbrushing frequency in children (the reference group: more than once per day, the low group: once per day, and the very-low group: less than once per day) was examined using Poisson regression models with adjustments for maternal and child characteristics after multiple imputations for missing data., Results: The prevalence of maternal postpartum depression at one and six months postpartum was 13.9% and 11.4%, respectively; the proportions of each persistence group were 81.1% ('Resilient'), 7.5% ('Improving'), 5.0% ('Emergent') and 6.4% ('Chronic'). Concerning children's toothbrushing frequency, 51.6% and 0.5% of participants self-reported frequencies of once per day and less than once per day, respectively. The association of maternal postpartum depression with a lower toothbrushing frequency in children consistently had higher relative risks (RRs). However, these associations were weakened when adjusting for whether the child could self-perform toothbrushing or whether this was done under parental supervision. A key result is that participants with persistent postpartum depression at both one and six month(s) postpartum showed the highest adjusted RRs (95% CI) for lower toothbrushing frequency in children (1.08 [1.04-1.12] with a decrease in children's toothbrushing frequency)., Conclusion: Maternal mental health provides valuable screening information for children with lower toothbrushing frequency for the purpose of preventing ECC., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Environmental carbon dioxide (CO 2 ) could affect various mental and physiological activities in humans, but its effect on daytime sleepiness is still controversial. In a randomized and counterbalanced crossover study with twelve healthy volunteers, we applied a combinational approach using classical frequentist and Bayesian statistics to analyze the CO 2 exposure effect on daytime sleepiness and electroencephalogram (EEG) signals. Subjective sleepiness was measured by the Japanese Karolinska Sleepiness Scale (KSS-J) by recording EEG during CO 2 exposure at different concentrations: Normal (C), 4000 ppm (Moderately High: MH), and 40 000 ppm (high: H). The daytime sleepiness was significantly affected by the exposure time but not the CO 2 condition in the classical statistics. On the other hand, the Bayesian paired t-test revealed that the CO 2 exposure at the MH condition might induce daytime sleepiness at the 40-min point compared with the C condition. By contrast, EEG was significantly affected by a short exposure to the H condition but not exposure time. The Bayesian analysis of EEG was primarily consistent with results by the classical statistics but showed different credible levels in the Bayes' factor. Our result suggested that the EEG may not be suitable to detect objective sleepiness induced by CO 2 exposure because the EEG signal was highly sensitive to environmental CO 2 concentration. Our study would be helpful for researchers to revisit whether EEG is applicable as a judgment indicator of objective sleepiness., (© 2022 The Authors. Indoor Air published by John Wiley & Sons Ltd.)

Preclinical studies reveal maternal exercise as a promising intervention to reduce the transmission of multigenerational metabolic dysfunction caused by maternal obesity. The benefits of maternal exercise on offspring health may arise from multiple factors and have recently been shown to involve DNA demethylation of critical hepatic genes leading to enhanced glucose metabolism in offspring. Histone modification is another epigenetic regulator, yet the effects of maternal obesity and exercise on histone methylation in offspring are not known. Here, we find that maternal high-fat diet (HFD; 60% kcal from fat) induced dysregulation of offspring liver glucose metabolism in C57BL/6 mice through a mechanism involving increased reactive oxygen species, WD repeat-containing 82 (WDR82) carbonylation, and inactivation of histone H3 lysine 4 (H3K4) methyltransferase leading to decreased H3K4me3 at the promoters of glucose metabolic genes. Remarkably, the entire signal was restored if the HFD-fed dams had exercised during pregnancy. WDR82 overexpression in hepatoblasts mimicked the effects of maternal exercise on H3K4me3 levels. Placental superoxide dismutase 3 (SOD3), but not antioxidant treatment with N-acetylcysteine was necessary for the regulation of H3K4me3, gene expression, and glucose metabolism. Maternal exercise regulates a multicomponent epigenetic system in the fetal liver resulting in the transmission of the benefits of exercise to offspring., (© 2022 by the American Diabetes Association.)

Cleft lip and/or palate (CL/P), the most prevalent congenital anomaly, is understood to negatively affect a wide range of child development. Since the concept remains controversial, because most published work is from cross-sectional studies, we examined the neurodevelopmental trajectories in participants with CL/P through a longitudinal comparison with the general population during early childhood using data from a nationwide birth cohort study in Japan. The linear mixed models for each domain of the Ages and Stages Questionnaire, third edition (ASQ-3), were used to detect differences in standardised mean scores between groups. The ASQ-3 is a general neurodevelopmental screening tool comprising communication, gross motor, fine motor, problem-solving, and personal-social domains. Participants' neurodevelopment was determined semi-annually from 6 to 36 months of age. The trajectories of standardised mean scores in each domain showed several significant differences between the control and CL/P groups, with the maximum difference at 24 months of age in the communication domain. Indeed, CL/P was associated with significantly lower scores in the communication (coefficient: -3.31, 95% CI: -5.09 to -1.14), problem-solving (coefficient: -3.13, 95% CI: -5.07 to -1.18), and personal-social domains (coefficient: -1.99, 95% CI: -3.87 to -0.11). Trajectories of ASQ-3 scores suggest neurodevelopmental delays in children with CL/P., (© 2022 Scandinavian Division of the International Association for Dental Research. Published by John Wiley & Sons Ltd.)

We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst)  eV and 6463.7±0.3(stat)±0.1(syst)  eV, and widths to be 2.5±1.0(stat)±0.4(syst)  eV and 1.0±0.6(stat)±0.3(stat)  eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650  MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst)  mb for 470

Background: Daily toothbrushing prevents early childhood caries, but reinforcement depends on facilitative parenting behaviours. Mother-to-infant bonding, the maternal affection towards the infant, is an environmental factor that strongly influences parenting., Aim: This study examined the association between maternal bonding and children's daily toothbrushing frequency., Design: The sample consisted of 83 954 mother-infant pairs at two years postpartum, derived from the initial sample of JECS (cohort study), which included 104 062 foetuses. Maternal bonding disorders were assessed using the Mother-to-Infant Bonding Scale (MIBS). After multiple imputation for missing data, a multinomial logistic regression analysis was conducted with adjustments for several maternal (eg, age at delivery) and child-related (eg, self-performed toothbrushing) variables., Results: The odds ratio (95% confidence interval) for the association of maternal bonding disorders with the low (once per day) and the very low child toothbrushing frequency (<1 per day) was 1.12 (1.07-1.17) and 1.23 (0.91-1.66), respectively, after covariate adjustments. Furthermore, the univariate general linear model showed that the mean MIBS scores significantly decreased as the daily child toothbrushing frequency increased., Conclusions: The prevalence of maternal bonding disorders at one year postpartum was prospectively associated with a lower frequency of child toothbrushing at two years of age., (© 2021 BSPD, IAPD and John Wiley & Sons Ltd.)

Background: Low back pain (LBP) is a common health problem - sitting on a chair for a prolonged time is considered a significant risk factor. Furthermore, the level of LBP may vary at different times of the day. However, the role of the time-sequence property of sitting behavior in relation to LBP has not been considered. During the dynamic sitting, small changes, such as slight or big sways, have been identified. Therefore, it is possible to identify the motif consisting of such changes, which may be associated with the incidence, exacerbation, or improvement of LBP. Method: Office chairs installed with pressure sensors were provided to a total of 22 office workers (age = 43.4 ± 8.3 years) in Japan. Pressure sensors data were collected during working days and hours (from morning to evening). The participants were asked to answer subjective levels of pain including LBP. Center of pressure (COP) was calculated from the load level, the changes in COP were analyzed by applying the Toeplitz inverse covariance-based clustering (TICC) analysis, COP changes were categorized into several states. Based on the states, common motifs were identified as a recurring sitting behavior pattern combination of different states by motif-aware state assignment (MASA). Finally, the identified motif was tested as a feature to infer the changing levels of LBP within a day. Changes in the levels of LBP from morning to evening were categorized as exacerbated, did not change, or improved based on the survey questions. Here, we present a novel approach based on social spider algorithm (SSA) and probabilistic neural network (PNN) for the prediction of LBP. The specificity and sensitivity of the LBP inference were compared among ten different models, including SSA-PNN. Result: There exists a common motif, consisting of stable sitting and slight sway. When LBP level improved toward the evening, the frequency of motif appearance was higher than when LBP was exacerbated ( p < 0.05) or the level did not change. The performance of the SSA-PNN optimization was better than that of the other algorithms. Accuracy, precision, recall, and F1-score were 59.20, 72.46, 40.94, and 63.24%, respectively. Conclusion: A lower frequency of a common motif of the COP dynamic changes characterized by stable sitting and slight sway was found to be associated with the exacerbation of LBP in the evening. LBP exacerbation is predictable by AI-based analysis of COP changes during the sitting behavior of the office workers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Wang, Sato, Nawrin, Widatalla, Kimura and Nagatomi.)

Study Design: A cross-sectional study., Objective: The purpose of this large cohort study was to assess the prevalence of low back pain (LBP) among young players participating in several types of sports., Summary of Background Data: LBP is a significant problem among young sports players. Sport discipline among young players is thought to be associated with LBP. However, similar previous studies did not specifically analyze LBP by age and sex., Methods: A cross-sectional study was conducted with young sports players (ages 6-15 years, n = 7277) using a self-reported questionnaire. The prevalence of LBP was assessed using the variables of age, sex, and sport discipline., Results: The point prevalence of LBP among young sports players was 5.0%. The participants between 6 and 8 years' old had the lowest prevalence of LBP (0.4%-1.3%), which increased with aging and reached the highest proportion of 13.5% to 14.8% at 13 to 14 years. Furthermore, female players had significantly higher proportions of LBP than male players (8.1% vs. 3.7%). Regarding sport discipline, the prevalence of LBP was higher in basketball, handball, and volleyball., Conclusion: The prevalence of LBP among young sports players was different for age, sex, and sport discipline. Further studies are needed to clarify the association of sport-specific movements to LBP in each sport discipline. This may assist in developing programs or strategies for preventing LBP among young sports players.Level of Evidence: 3., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Rhinovirus (RV) is a primary etiologic agent of common cold that can subsequently acutely exacerbate bronchial asthma or chronic obstructive pulmonary disease. Kakkonto (Ge-gen-tang in Chinese), one of the most frequently prescribed traditional Japanese (Kampo) medicines, is used for treating common cold, shoulder stiffness, or inflammatory diseases of the upper body. Previous experimental studies have indicated that kakkonto exerts antiviral and anti-inflammatory effects on the influenza virus and the human respiratory syncytial virus. However, there is a lack of reports investigating the efficacy of kakkonto in RV infection. Hence, the aim of the current study was to investigate the effects of kakkonto on RV infection of human nasal epithelial (HNE) cells. HNE cells obtained via endoscopic sinus surgery were cultured and infected with RV14, with or without kakkonto treatment. The supernatants from the cells were collected, and the RV14 titer and cytokine levels were assessed. Reverse transcription-polymerase chain reaction was performed to determine the amount of viral RNA, while the level of nuclear factor kappa B (NF-κB) subunits in the nucleus was assessed by enzyme-linked immunosorbent assay. Although kakkonto treatment did not reduce RV14 titer or RNA levels, indicating that it did not inhibit RV14 proliferation, it was found to reduce the production of specific pro-inflammatory cytokines, including interleukin (IL)-8, tumor necrosis factor (TNF)-α, and monocyte chemotactic protein-1 (MCP-1). Unlike that observed with the kakkonto extract, none of the crude drugs contained in kakkonto reduced IL-8 level. Furthermore, though kakkonto treatment significantly reduced p50 levels, it did not impact the p65 subunit of NF-κB. These results indicated that kakkonto can inhibit inflammation caused by RV infection and may exert an immunomodulatory effect on HNE cells. This is the first report to elucidate the effects of kakkonto extract on RV infection in primary cultures of HNE cells, providing evidence that kakkonto may act as an effective therapy for RV infection and subsequent airway inflammation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Saito, Kikuchi, Yamaya, Deng, Sugawara, Takayama, Nagatomi and Ishii.)

The ubiquitin-proteasome system is a major protein degradation pathway in the cell. Proteasomes produce several peptides that are rapidly degraded to free amino acids by intracellular aminopeptidases. Our previous studies reported that proteolysis via proteasomes and aminopeptidases is required for myoblast proliferation and differentiation. However, the role of intracellular aminopeptidases in myoblast proliferation and differentiation had not been clarified. In this study, we investigated the effects of puromycin-sensitive aminopeptidase (PSA) on C2C12 myoblast proliferation and differentiation by knocking down PSA. Aminopeptidase enzymatic activity was reduced in PSA-knockdown myoblasts. Knockdown of PSA induced impaired cell cycle progression in C2C12 myoblasts and accumulation of cells at the G2/M phase. Additionally, after the induction of myogenic differentiation in PSA-knockdown myoblasts, multinucleated circular-shaped myotubes with impaired cell polarity were frequently identified. Cell division cycle 42 (CDC42) knockdown in myoblasts resulted in a loss of cell polarity and the formation of multinucleated circular-shaped myotubes, which were similar to PSA-knockdown myoblasts. These data suggest that PSA is required for the proliferation of myoblasts in the growth phase and for the determination of cell polarity and elongation of myotubes in the differentiation phase., (© 2020 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals LLC.)

Exercise can alter the composition of gut microbiota. However, studies examining the effects of exercise on gut microbiota in the elderly are lacking. This study aims to investigate whether an 8-week exercise training affect gut microbiota in physically inactive elderly women. Fourteen women were randomly assigned to either exercise group or control group. Repeated-measures analysis of variance was used to reveal changes in gut microbiota. Alpha diversity did not change significantly. A tendency to form 2 clusters was observed for operational taxonomic units (OTU) after intervention. At phylum, class, and order levels, a significant difference was observed between two groups for Fusobacteria (F=5.257, P=0.045), Betaproteobacteria (F=5.149, P=0.047), and Bifidobacteriales (F=7.624, P=0.020). A significant interaction was observed between two groups for Actinobacteria (F=8.434, P=0.016). At family and genus levels, a significant main effect of groups was observed in Bifidobacteriaceae (F=7.624, P=0.020), Bifidobacterium (F=7.404, P=0.022), and Gemmiger (F=5.881, P=0.036). These findings indicate that an 8-week exercise training may induce partial changes in relative abundance and OTU clustering of gut microbiota in physically inactive elderly women. Also, exercise may increase the abundance of bacteria associated with anti-inflammation such as Verrucomicrobia, reduce the abundance of bacteria associated with pro-inflammation such as Proteobacteria., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background: Grip strength reflects systemic muscle strength and mass and is reportedly associated with various metabolic variables. However, its prognostic association with dyslipidemia is unknown. We examined the association of grip strength and other physical fitness markers with the incidence of dyslipidemia among Japanese adults., Methods: A total of 16,149 Japanese (6,208 women) individuals aged 20-92 years who underwent a physical fitness test between April 2001 and March 2002 were included in this cohort study. Grip strength, vertical jump, single-leg balance with eyes closed, forward bending, and whole-body reaction time were evaluated at baseline. Dyslipidemia was annually determined based on fasting serum lipid profiles and self-reported dyslipidemia from April 2001 to March 2008., Results: During the follow-up period, 4,458 (44.9%) men and 2,461 (39.6%) women developed dyslipidemia. A higher relative grip strength (grip strength/body mass index) was associated with a lower incidence of dyslipidemia among both men and women (P for trend <0.001). Compared with those for the first septile, the hazards ratios and 95% confidence intervals (CIs) for the seventh septile were 0.56 (95% CI, 0.50-0.63) for men and 0.69 (95% CI, 0.58-0.81) for women. Moreover, relative vertical jump (vertical jump strength/body mass index) was also inversely associated with the incidence of dyslipidemia among both men and women (P for trend <0.001). There was no association between other physical fitness and dyslipidemia among both men and women., Conclusion: Relative grip strength and vertical jump may be useful risk markers of the incidence of dyslipidemia.

Communication between parents and their children's coaches is important for children's sports activities, but the relationship between parents and coaches is not well understood. It is possible that parents feel a lack of communication with coaches, which could be due to parents' experience with sports activities or the social environment of the team. This study aimed to elucidate the characteristics of parents who feel a lack of communication with their children's coaches of youth sports. A cross-sectional study was conducted on parents of young athletes (n = 6,641) and multivariate logistic regression analyses were performed to assess factors related to parents' feeling of a lack of communication with their children's coaches. Among the respondents, 29.4% of parents felt a lack of communication with their children's coaches. The factors related to the parents' feeling were a shorter duration of their children playing the present sport, an absence of experience playing the same sport as their children or playing in a team with high competition level, dissatisfaction with their children's attitude towards sports activities, and an awareness of verbal and/or physical abuse by the coaches and bullying by the teammates in their children's team. Parents' previous sports experience and awareness of interpersonal violence in their children's team were associated with their feeling of a lack of communication with coaches. Educating parents on the sport and their roles in youth sport is necessary to make appropriate mutual communication between parents and coaches, which could lead to better circumstances for young athletes.

Purpose: We examined the possibility that wearing a below-knee compression garment (CG) reduces fatigue-induced strength loss and joint position sense (JPS) errors in healthy adults., Methods: Subjects (n = 24, age = 25.5 ± 4 years) were allocated to either one of the treatment groups that performed 100 maximal isokinetic eccentric contractions at 30° -1 with the right-dominant knee extensors: (1) with (EXPCG) or (2) without CG (EXP) or to (3) a control group (CONCG: CG, no exercise). Changes in JPS errors, and maximal voluntary isometric contraction (MVIC) torque were measured immediately post-, 24 h post-, and 1 week post-intervention in each leg. All testing was done without the CG., Results: CG afforded no protection against JPS errors. Mixed analysis of variance (ANOVA) revealed that absolute JPS errors increased post-intervention in EXPCG and EXP not only in the right-exercised (52%, p = 0.013; 57%, p = 0.007, respectively) but also in the left non-exercised (55%, p = 0.001; 58%, p = 0.040, respectively) leg. Subjects tended to underestimate the target position more in the flexed vs. extended knee positions (75-61°: - 4.6 ± 3.6°, 60-50°: - 4.2 ± 4.3°, 50-25°: - 2.9 ± 4.2°), irrespective of group and time. Moreover, MVIC decreased in EXP but not in EXPCG and CONCG at immediately post-intervention (p = 0.026, d = 0.52) and 24 h post-intervention (p = 0.013, d = 0.45) compared to baseline., Conclusion: Altogether, a below-knee CG reduced fatigue-induced strength loss at 80° knee joint position but not JPS errors in healthy younger adults.

A large number of intracellular proteins are degraded by the ubiquitin-proteasome system, one of the major protein degradation pathways. It produces peptides of several different sizes through protein degradation, and these peptides are rapidly degraded into free amino acids by various intracellular aminopeptidases. Previously, we reported that the activity of proteasomes and aminopeptidases in the proteolysis pathway are necessary for myoblast proliferation and differentiation. However, the detailed function of intracellular aminopeptidases in myoblast proliferation and differentiation has not yet been elucidated. In this study, we focused on alanine aminopeptidase (APN) and investigated the function of APN in C2C12 myoblast proliferation and differentiation. In myoblasts and myotubes, APN was mainly localized in the cell membrane as well as expressed at low levels in the cytoplasm and nucleus. The reduction of the APN enzymatic activity impaired the cell cycle progression in C2C12 myoblasts. In addition, apoptosis was induced after APN-knockdown. Finally, myogenic differentiation was also delayed in the APN-suppressed myoblasts. These findings indicate that APN is required for myoblast proliferation and differentiation., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

It has been reported that Bach1-deficient mice show reduced tissue injuries in diverse disease models due to increased expression of heme oxygenase-1 (HO-1)that possesses an antioxidant function. In contrast, we found that Bach1 deficiency in mice exacerbated skeletal muscle injury induced by cardiotoxin. Inhibition of Bach1 expression in C2C12 myoblast cells using RNA interference resulted in reduced proliferation, myotube formation, and myogenin expression compared with control cells. While the expression of HO-1 was increased by Bach1 silencing in C2C12 cells, the reduced myotube formation was not rescued by HO-1 inhibition. Up-regulations of Smad2, Smad3 and FoxO1, known inhibitors of muscle cell differentiation, were observed in Bach1-deficient mice and Bach1-silenced C2C12 cells. Therefore, Bach1 may promote regeneration of muscle by increasing proliferation and differentiation of myoblasts., Competing Interests: The authors have declared that no competing interests exist.

Martial arts, such as judo, kendo, and karate, are popular worldwide, not only among adults but also among children and adolescents. Although low back pain (LBP) is considered to be a common problem in these sports, it has been scarcely studied, especially in young athletes. The purpose of this study was to elucidate the point prevalence of and factors related to LBP among school-aged athletes in judo, kendo, and karate. A cross-sectional study was conducted in school-aged athletes (age, 6-15 years; n = 896) using a self-reported questionnaire. Multiple logistic regression models were used to assess the factors related to LBP along with the odds ratio (OR) and 95% confidence interval (95% CI). Variables included in the analysis were sex, age, body mass index, team level, number of days and hours of training, frequency of participation in games, practice intensity, and lower extremity pain. The prevalence of LBP was 6.9% in judo, 4.7% in kendo, and 2.9% in karate. Older age was significantly associated with LBP in judo (adjusted OR, 2.12 [95% CI, 1.24-3.61]), kendo (1.77 [1.27-2.47]), and karate (2.22 [1.14-4.33]). Lower extremity pain was significantly associated with LBP in judo (6.56 [1.57-27.34]) and kendo (21.66 [6.96-67.41]). Coaches should understand the characteristics of LBP in each martial art to develop strategies to prevent LBP among school-aged martial arts athletes.

Background: Low back pain (LBP) is a common problem among young basketball players in addition to lower extremity injuries. However, studies that focus on LBP with lower extremity pain are limited. From the perspective of the kinematic chain, disrupted lower extremity function can lead to LBP. The association between these two symptoms in basketball players, however, has not been reported. Therefore, this study aimed to clarify the association between lower extremity pain and LBP among young basketball players., Methods: This cross-sectional study was conducted on school-aged basketball players ( n  = 592). Information regarding their sporting activities was collected using a self-reported questionnaire. Musculoskeletal pain such as low back, knee, and ankle pain was assessed. The sports players with knee and/or ankle pain were defined as having lower extremity pain. Multivariate logistic regression analysis was used to assess the association between lower extremity pain and LBP. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. The associations of knee or ankle pain with LBP were similarly assessed., Results: School-aged basketball players had a point prevalence of 12.8% for LBP. Compared with the players without lower extremity pain, the players with lower extremity pain had higher rates of LBP, with an adjusted OR (95% CI) of 6.21 (3.57-10.80). There was also a significant association of knee and ankle pain with LBP. Compared with the players without knee or ankle pain, the adjusted ORs (95% CI) for LBP were 4.25 (2.55-7.07) in the players with knee pain and 3.79 (2.26-6.36) in the players with ankle pain., Conclusions: Lower extremity pain was associated with LBP among school-aged basketball players. Further research is needed to clarify the mechanism of this association, which will provide useful information for prevention and treatment of LBP among young basketball players., Competing Interests: Competing interestsThe authors declare no potential conflicts of interest., (© The Author(s) 2020.)

Rhinoviral infection is associated with an increased risk of asthma attacks. The macrolide clarithromycin decreases cytokine production in nasopharyngeal aspirates from patients with wheezing, but the effects of macrolides on cytokine production in nasal epithelial cells obtained from asthmatic subjects remain unclear. Here, human nasal epithelial cells were infected with type-14 rhinovirus (RV14), a major RV group. Titers and RNA of RV14 and cytokine concentrations, including IL-1β and IL-6, were higher in the supernatants of the cells obtained from subjects with bronchial asthma (asthmatic group) than in those from the non-asthmatic group. Pretreatment with clarithromycin decreased RV14 titers, viral RNA and cytokine concentrations, and susceptibility to RV14 infection. Pretreatment with clarithromycin also decreased IL-33 production, which was detected after infection. Pretreatment with clarithromycin decreased the expression of intercellular adhesion molecule-1, the receptor for RV14, after infection, the number and fluorescence intensity of the acidic endosomes through which RV RNA enters the cytoplasm, and the activation of nuclear factor kappa-B proteins in nuclear extracts. These findings suggested that RV replication and cytokine production may be enhanced in nasal epithelial cells obtained from subjects with bronchial asthma and may be modulated by clarithromycin.

Objectives: Data regarding the association between adiponectin levels and body mass index (BMI) and long-term changes in depressive symptoms are limited and inconsistent. Thus, we investigated whether circulating adiponectin levels and BMI were independently and combinedly correlated to longitudinal changes in depressive symptoms. Methods: This prospective cohort study evaluated 269 elderly Japanese individuals aged ≥70 years who participated in the Tsurugaya Project conducted between 2002 and 2012. A short form of the Geriatric Depression Scale (GDS) was used to assess depressive status. Serum adiponectin levels were measured using an enzyme-linked immunosorbent assay or a latex particle-enhanced turbidimetric immunoassay. BMI was calculated as body weight (kg)/height (m 2 ). Results: Multiple linear regression analysis revealed that baseline serum adiponectin levels were positively associated with changes in GDS scores ( β  = 0.14, P  = 0.035). However, no association was observed after adjusting for BMI ( β  = 0.09, P  = 0.185). Low BMI was associated with increased GDS scores at the 10-year follow-up ( β = -0.14, P  = 0.033). Participants with a combination of high adiponectin levels and low BMI had a 3.3-fold higher risk of worsening depressive symptoms than those with low adiponectin levels and high BMI (odds ratio: 3.35, 95% confidence interval: 1.60-7.00; P  = 0.001). Conclusions: This longitudinal study indicated that high serum adiponectin levels and low BMI were both associated with worsening depressive symptoms among older Japanese individuals. Furthermore, the combination of high adiponectin levels and low BMI was associated with worsening depressive symptoms.

Motor skill practice improves performance not only in the trained - but also in the untrained contralateral limb - a phenomenon called as interlimb transfer. Handedness affects motor skill acquisition and interlimb transfer, but it remains unknown whether handedness affects interlimb transfer when practicing with the dominant or non-dominant limb. We have hypothesized that interlimb transfer of skill acquisition differs between left- and right-handed participants, and that right- as compared with left-hand motor skill practice shows greater interlimb transfer, regardless of handedness. Strongly left-hand (n = 12, aged 27.3 ± 4.4 years; 3 female) and right-hand dominant (n = 12, 20.7 ± 3.8 years; 5 female) subjects with no history of neurological or orthopedic disorders performed the grooved pegboard test before and after 4 blocks of practice on the same apparatus. Subjects were timed on their speed of the task. Right-handed subjects failed to improve manual performance in their right hand after right- or left-hand motor practice. In contrast, they showed improvement on the left hand in each condition. These data suggest greater interlimb transfer after right-hand motor skill practice, but no interlimb transfer after left-hand practice. On the other hand, our results show consistent interlimb transfer effects in left-handed subjects, irrespective of whether the dominant left or the non-dominant right arm has been initially trained. In conclusion, our results add to the body of literature by detecting the differences in the magnitude of motor skill acquisition and interlimb transfer between left- and right-handed subjects after short-term unilateral motor skill practice.

Background: Lower back pain (LBP), as well as lower extremity injuries, are major problems among young volleyball players. Nevertheless, only few studies have focused on the relationship between lower extremity injuries and LBP., Objective: This study investigated the association between LBP and lower extremity pain, including knee and ankle pain, among young volleyball players., Design: Cross-sectional study., Setting: Amateur sports association., Participants: Elementary and middle school-aged athletes (6-15 years of age)., Main Outcome Measures: LBP and lower extremity pain., Results: A total of 566 young volleyball players participated in this study. The point prevalence of LBP among young volleyball players was 9.5%. Using absence of lower extremity pain as a reference, the adjusted odds ratio (95% confidence interval) for LBP was 11.07 (5.64-21.71) in the presence of lower extremity pain., Conclusions: LBP is associated with Lower extremity pain among young volleyball players. Careful attention should be paid to lower extremity complaints to prevent and treat LBP among young volleyball players., Competing Interests: Declaration of competing interest None declared., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The number of patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly increased, although the WHO declared a pandemic. However, drugs that function against SARS-CoV-2 have not been established. SARS-CoV-2 has been suggested to bind angiotensin-converting enzyme 2, the receptor of the SARS coronavirus. SARS coronavirus and coronavirus 229E, the cause of the common cold, replicate through cell-surface and endosomal pathways using a protease, the type II transmembrane protease. To examine the effects of protease inhibitors on the replication of coronavirus 229E, we pretreated primary cultures of human nasal epithelial (HNE) cells with camostat or nafamostat, each of which has been used for the treatment of pancreatitis and/or disseminated intravascular coagulation. HNE cells were then infected with coronavirus 229E, and viral titers in the airway surface liquid of the cells were examined. Pretreatment with camostat (0.1-10 μg/mL) or nafamostat (0.01-1 μg/mL) reduced the titers of coronavirus 229E. Furthermore, a significant amount of type II transmembrane protease protein was detected in the airway surface liquid of HNE cells. Additionally, interferons have been reported to have antiviral effects against SARS coronavirus. The additive effects of interferons on the inhibitory effects of other candidate drugs to treat SARS-CoV-2 infection, such as lopinavir, ritonavir and favipiravir, have also been studied. These findings suggest that protease inhibitors of this type may inhibit coronavirus 229E replication in human airway epithelial cells at clinical concentrations. Protease inhibitors, interferons or the combination of these drugs may become candidate drugs to inhibit the replication of SARS-CoV-2.

The ubiquitin-proteasome pathway is essential for skeletal muscle growth and development. Proteasomes generate oligopeptides in the cytoplasm, and these peptides are considered to be rapidly degraded to amino acids by several intracellular aminopeptidases. However, the role of intracellular aminopeptidases in muscle growth remains unknown. In this study, therefore, we investigated the role of intracellular aminopeptidases in C2C12 myoblast proliferation and differentiation. Inhibition of intracellular aminopeptidases by Bestatin methyl ester (Bes-ME) decreased leucine and alanine aminopeptidase activity, and impaired proliferation and differentiation of C2C12 myoblasts. Furthermore, we observed that the inhibition of intracellular aminopeptidases reduced intracellular levels of amino acid and ATP level, and suppressed the phosphorylation of the mTOR pathway. These results suggested that intracellular aminopeptidases affect C2C12 myoblast proliferation and differentiation via mTOR pathway; however, further studies are required to clarify the role of aminopeptidase in skeletal muscle., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Mutations in dysferlin are responsible for a group of progressive, recessively inherited muscular dystrophies known as dysferlinopathies. Using recombinant proteins and affinity purification methods combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS), we found that AMP-activated protein kinase (AMPK)γ1 was bound to a region of dysferlin located between the third and fourth C2 domains. Using ex vivo laser injury experiments, we demonstrated that the AMPK complex was vital for the sarcolemmal damage repair of skeletal muscle fibers. Injury-induced AMPK complex accumulation was dependent on the presence of Ca 2+ , and the rate of accumulation was regulated by dysferlin. Furthermore, it was found that the phosphorylation of AMPKα was essential for plasma membrane repair, and treatment with an AMPK activator rescued the membrane-repair impairment observed in immortalized human myotubes with reduced expression of dysferlin and dysferlin-null mouse fibers. Finally, it was determined that treatment with the AMPK activator metformin improved the muscle phenotype in zebrafish and mouse models of dysferlin deficiency. These findings indicate that the AMPK complex is essential for plasma membrane repair and is a potential therapeutic target for dysferlinopathy., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)

Basketball is a major sport worldwide among different age groups that leads to a high frequency of injuries at multiple body sites. Upper and lower extremities and lower back are common pain sites in basketball players; however, there is little information about the relationship between upper or lower extremity pain and lower back pain. This study elucidated the associations between upper extremity (shoulder and elbow) pain and lower back pain (LBP) among young basketball players. We conducted a cross-sectional study using self-reported questionnaires mailed to 25,669 young athletes; the final study population comprised 590 basketball players, and their median age was 13 years (range: 6-15 years). The point prevalence rates of lower back, shoulder, elbow, and upper extremity pain among young basketball players were 12.9% (76/590), 4.6% (27/590), 2.7% (16/590), and 7.1% (42/590), respectively. Multivariate logistic regression analyses revealed that upper extremity pain was significantly associated with LBP (adjusted odds ratio [OR]: 7.86; 95% confidential interval [CI], 3.93-15.72). Shoulder pain was significantly associated with training per week (> 4 days) (adjusted OR: 4.15; 95% CI: 1.29-13.40) and LBP (adjusted OR: 13.77; 95% CI: 5.70-33.24). This study indicates that upper extremity and shoulder pain is associated with LBP among young basketball players. Assessing for lower back pain, as well as elbow and/or shoulder pain, may help prevent severe injuries in young basketball players. In conclusion, parents and coaches should be properly re-educated to help improve lower back, upper extremity, and shoulder pain among young basketball players.

Background: The relationship between isoflavone intake and depressive symptoms has been examined among premenopausal and postmenopausal women but not among men. Therefore, we investigated whether isoflavone intake is associated with depressive symptoms among men., Methods: This cross-sectional study was conducted between 2008 and 2011. A total of 1335 Japanese men aged 19-83 participated in the present study. Isoflavone intake was measured using the Brief-type Self-administered Diet History Questionnaire (BDHQ). Depressive symptoms were assessed using the Self-rating Depression Scale (SDS), and two cut-off values (i.e., 40 and 50) were used. Multiple logistic regression analysis was conducted to examine the association between isoflavone intake and depressive symptoms., Results: When the cut-off value for SDS was specified as 40, the odds ratios (ORs) for depressive symptoms were higher for the categories that were characterized by high rather than low levels of isoflavone intake in the crude model (p = 0.002). This association remained unchanged (p = 0.029) when potential cofounds were controlled for in Model 3. Multivariate linear regression analysis also showed a significant inverse association between isoflavone intake and SDS scores (p = 0.027; final adjusted model)., Limitations: Cross-sectional study is difficult to draw any conclusions about causality CONCLUSIONS: The findings suggest that a high level of dietary isoflavone intake is associated with a lower prevalence of depressive symptoms among men. Therefore, isoflavone intake may have a beneficial effect on men's mental health., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Cleft lip and/or palate is among the most prevalent congenital birth defects, and negatively affects maternal psychological status and may consequently result in higher prevalence of child maltreatment. However, the association of childbirths of infants with cleft lip and/or palate with maternal emotional involvement still remains unclear. We examined the association between childbirths of infants with cleft lip and/or palate and mother-to-infant bonding, using data from the Japan Environment and Children's Study, a nationwide birth cohort study., Methods: A cross-sectional study using the jecs-an-20,180,131 dataset was performed. A total 104,065 fetuses in 15 regional centres in Japan were enrolled after obtaining informed written consent. The Mother-to-Infant Bonding Scale, a self-report scale consisting of 10 items, was used to evaluate maternal bonding at one year after childbirth. Finally, the participants consisted of 79,140 mother-infant pairs, of which 211 mothers of infants with cleft lip and/or palate were included in our analyses. Multivariable logistic regression analysis using multiple imputation for missing data was performed to calculate the odds ratio and 95% confidence interval in the estimation of the association between bonding disorders and childbirths with cleft lip and/or palate., Results: No increased risk of bonding disorders was observed among all the mothers of infants with cleft lip and/or palate (odds ratio [95% confidence interval]; 0.97 [0.63-1.48], p = 0.880), however, advanced maternal age or multiple parity may adversely affect the associations between bonding disorders and cleft lip and/or palate, respectively. After stratification with a combination of maternal age and parity, a significant association of cleft lip and/or palate with bonding disorders was found only among advanced-age multiparae (odds ratio [95% confidence interval] = 2.51 [1.17-5.37], p = 0.018), but it was weakened after additional adjustment for maternal depression., Conclusions: Childbirths of infants with cleft lip and/or palate may increase the risk of bonding disorders among advanced-age multiparae, possibly through maternal depression. This finding provides valuable information for the provision of multidisciplinary cleft care.

Verbal or physical abuse from coaches has negative effects on young athletes, and the parents of athletes also have an influence on the sports environment. It is therefore important to understand parents' attitudes towards abuse against their children from the coaches. This study aimed to elucidate the characteristics of parents who accept the infliction of verbal or physical abuse on their children from coaches of youth sports teams. A cross-sectional study using self-report questionnaires was conducted with parents of young athletes (n = 6,493). Multivariate logistic regression models were used to assess the factors associated with parents' acceptability of verbal or physical abuse against their children. The proportion of parents who were accepting of verbal or physical abuse was 21.5%. Acceptability of verbal or physical abuse was significantly associated with male (odds ratio: 1.67, 95% confidence interval: 1.43-1.95), younger age (1.24, 1.09-1.41), lower educational attainment (1.32, 1.17-1.50), smoking habits (1.42, 1.23-1.63), experience of playing on a team with high levels of competition during their junior or high school days (1.31, 1.15-1.50), and experience of verbal and physical abuse by their own former coaches (3.59, 3.03-4.26 and 1.17, 1.02-1.35). About 58% and 28% of parents had experienced verbal and physical abuse from their own former coaches, and parents who had experienced verbal abuse themselves were most likely to be accepting of verbal or physical abuse towards their children. Educating parents is considered to be important for preventing and eradicating abuse against young athletes.

Aim: Right-handed young adults perform target-matching tasks more accurately with the non-dominant (ND) compared to the dominant (D) limb, but it is unclear if age affects this disparity. We determined if age affects target-matching asymmetry in right-side dominant healthy adults. Method: Young ( n  = 12, age: 23.6 y, 6 females) and older ( n  = 12; age: 75.1 y, 7 females) adults performed a passive joint position-matching task with the D and ND leg in a randomized order. Result: Age affected absolute, constant, and variable knee JPS errors but, contrary to expectations, it did not affect target-matching asymmetries between the D and ND knees. However, older participants tended to underestimate while young subjects overestimated the target angles. Moreover, older as compared to young subjects performed the target-matching task with higher variability. Conclusion: Altogether, age seems to affect passive knee target-matching behaviour in right-side dominant healthy adults. The present data indicate that healthy aging produces age-specific modifications in passive joint position sense.

Background: This prospective cohort study aimed to investigate the association between daily seaweed intake and depressive symptoms., Methods: In a prospective study conducted between 2008 and 2011, 500 Japanese adult employees aged 20-74 years participated and were included in the final analysis. Consumption of seaweed was assessed using a brief self-administered diet history questionnaire, and changes in seaweed consumption were divided into three categories (decreased, unchanged, and increased). Depressive symptoms were assessed using a Japanese version of the Self-Rating Depression Scale (SDS). Depressive symptoms were defined as an SDS score of ≥50 in the present study., Results: At the 3-year follow-up, 46 participants (9.2%) showed depressive symptoms. Multivariate analysis showed that baseline seaweed intakes were not significantly associated with the incidence of depressive symptoms (p for trend = 0.501). Conversely, odds ratios (95% CI) for depressive symptoms were lower in the participants who had higher seaweed intake than in those who had lower seaweed intake (decreased, 1.00; unchanged, 0.32 [0.13-0.81]; increased, 0.34 [0.13-0.88]; p for trend = 0.032) after adjusting for confounding factors., Conclusions: This study revealed a relationship between higher seaweed intake and a lower incidence of depressive symptoms in Japanese adults.

Athletes use compression garments (CGs) to improve sport performance, accelerate rehabilitation from knee injuries or to enhance joint position sense (JPS). The position of CGs around the knee may affect knee JPS but the data is inconsistent. The purpose of the present study was to determine the effects of CG position on healthy adults' knee joint position sense acuity. In a counterbalanced, single-blinded study, 16 healthy young adults (8 female, age: 25.5 y) performed an active knee joint position-matching task with and without (CON) a below-knee (BK), above-knee (AK), or whole-knee (WK) CG in a randomized order on the dominant (CompDom) or the non-dominant leg (CompNon-Dom). We also determined the magnitude of tissue compression by measuring anatomical thigh and calf cross sectional area (CSA) in standing using magnetic resonance imaging (MRI). Subjects had less absolute repositioning error (magnitude of error) in BK compared with CON condition. On the other hand, the analysis of the direction of error (constant error) revealed that in each condition subjects tended to underestimate the target position (AK, BK and CON: 75%; WK: 94%). In WK condition there was a significantly larger negative error (-2.7 ± 3.4) as compared with CON (-1.6 ± 3.7) condition. There also was less variable error, in WK compared to BK and CON conditions, indicating less variability in their position sense using a WK CG, regardless of the underestimation. CG reduced thigh CSA by 4.5 cm 2 or 3% and calf CSA by Δ1.3 cm 2 or 1%. The position of CG relative to the knee modifies knee JPS. The findings helps us better understand how the application of a WK CG may support athletic activities., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objectives: Studies have investigated the association between alcohol consumption and muscle mass and muscle disease. However, the relationship between alcohol consumption and muscle strength remains unclear. This study aimed to prospectively investigate the association between alcohol consumption and changes in muscle strength., Methods: This study evaluated 326 Japanese men and women over a 2-year period, assessing alcohol consumption using a brief, self administered diet-history questionnaire. Muscle strength was assessed using a digital grip dynamometer., Results: In a non-adjusted model, alcohol consumption was positively correlated with a decline in muscle strength (p for trend = 0.002). After adjusting model 1 for age, sex, and body mass index, adjusting model 2 for health status and fully adjusting model 3, there was a significant positive association between alcohol consumption and a decline in muscle strength, and this association showed no change over the 2-year period (p for trend = 0.006)., Conclusion: In this Japanese population, high alcohol consumption was associated with a greater decline in muscle strength. Future studies are needed to ascertain whether this relationship is present in other populations.

Verbal and physical abuse from coaches has negative effects on young athletes. Although the abuse can lead to the athletes' dropping out, no studies have reported on this topic. The purpose of this study was to elucidate the association between experience of verbal or physical abuse from coaches and loss of motivation for the present sport in young athletes. School-aged athletes (age range, 6-15 years, n = 6,791) were assessed using a self-reported questionnaire. Multivariate logistic regression models were used to assess the association between experience of verbal or physical abuse and loss of motivation for the present sport. Variables considered in the models were sex, age, body mass index, presence of bodily pain, team levels, number of training days per week, number of training hours per day on weekdays and weekends, and frequency of participation in games. The prevalence of loss of motivation for the present sport was 8.1%. Experience of verbal or physical abuse was significantly associated with loss of motivation for the present sport and the adjusted odds ratios (95% confidence intervals) were 1.93 (1.54-2.42, p < 0.001) for verbal abuse and 1.76 (1.27-2.42, p = 0.001) for physical abuse. Findings of this study suggest that experience of verbal or physical abuse from coaches is associated with loss of motivation for the present sport. Eradication of verbal and physical abuse from coaches is important for young athletes to continue sport participation.

Background: Simple physical fitness test can be a useful potential predictor of type 2 diabetes (T2DM). We examined the association between performances on simple physical fitness tests and the incidence of T2DM., Methods: This longitudinal study was conducted in 21,802 nondiabetic Japanese (6,649 women) aged 20 to 92 years, who underwent all physical fitness tests at baseline (April 2001 to March 2002). From April 2001 to March 2008, physical fitness tests, including grip strength, vertical jump, single-leg balance with eyes closed, forward bending, whole-body reaction time, and supine legs-up, were performed every year. Participants had physical fitness tests at least two times during the period. T2DM was also annually determined based on fasting blood glucose, glycated hemoglobin, and self-reported diabetes during the period. Discrete-time logit models were used to examine the influence of the serial level of each physical fitness test on the incidence of T2DM., Results: During the entire study period, 972 participants developed diabetes. Lower relative grip strength (grip strength/body weight) and single-leg balance performance were associated with a higher incidence of T2DM. For relative grip strength, as compared with the fourth quartile group, the odds ratios for other groups ranged from 1.16 to 1.56 (P for trend < 0.001). For single-leg balance, the odds ratios ranged from 1.03 to 1.49 (P for trend < 0.001)., Conclusion: The performance of a simple single-leg balance test as well as that of a grip strength test were negatively associated with the risk of T2DM among Japanese.

Objectives: Although maintaining cardiorespiratory fitness is encouraged to reduce the risk of hypertension, the level at, and length of time for which, individuals need to maintain fitness remains unclear. We examined the association between the frequency of achieving the recommended fitness levels of the 'Physical Activity Reference for Health Promotion 2013' and the risk of hypertension among Japanese men., Methods: This cohort study was conducted in 6653 men without hypertension enrolled in 1986. Whether the participants' fitness level was equal to or exceeded the reference value (fit) or not (unfit) was determined. The frequency of achieving the recommended fitness level was calculated by counting the number of times the fitness level was achieved in 1980 through 1986. Incident hypertension was defined as the first visit with a SBP/DBP of at least 140/90 mmHg or self-reported antihypertensive medication use and was evaluated during annual health examinations from 1986 until 2009., Results: During the follow-up period, 3630 men developed hypertension. The multivariable-adjusted hazard ratios (95% confidence interval) for incident hypertension comparing men with fit versus unfit at baseline was 0.79 (0.74-0.85). Moreover, the frequency of achieving the recommended fitness level was inversely associated with the incidence of hypertension. The risk of hypertension was lower among those who achieved three or more of the recommended levels (0.72 for three times to 0.62 for seven times)., Conclusion: Achieving the fitness level recommended in the Japanese guideline three or more times during a 6-year period can be beneficial for the risk reduction of hypertension.

Purpose: Considerable research has focused on shoulder and elbow injuries among baseball players; however, although lumbar spine and knee injuries are commonly experienced, they are less frequently studied. During common motions in baseball, such as throwing, hitting, and running, energy is transferred from the lower extremities through the lower back to the upper body. Lower extremity pain, as well as lower back pain (LBP), can disrupt the kinematic chain, and it is important to understand the association between lower extremity complaints and LBP. The purpose of this study was to elucidate the association between knee pain and LBP among young baseball players., Methods: A cross-sectional study was conducted with young baseball players (aged 6-15 years, n = 1,609) using a self-reported questionnaire. Multivariate logistic regression models were used for analyses. Variables considered in the models were sex, age, body mass index, team levels, number of days of training per week, number of hours in practice per day on weekdays and weekend, frequency of participation in games, practice intensity, and player position., Results: The point prevalence of LBP and knee pain was 8.4% and 13.1%, respectively. Knee pain was significantly associated with LBP. Using the absence of knee pain as a reference, the adjusted odds ratio (95% confidence interval) for LBP was 5.83 (3.93-8.65) (p < 0.001) in the presence of knee pain., Conclusions: Knee pain was associated with LBP among young baseball players. Clinicians should pay attention to knee complaints to prevent and treat LBP among young baseball players., Level of Evidence: III.

Background: Because the relationship between coaches and athletes is unequal, verbal and physical abuse remains a common problem among sports coaches. We aimed to elucidate the characteristics of baseball coaches who verbally/physically abuse young baseball players., Methods: A cross-sectional study was conducted on youth sports team coaches in Miyagi prefecture, Japan (n = 380), using a self-reported questionnaire. Multivariate logistic regression models were used for the analyses, evaluating the following variables: sex, age, educational level, smoking habits, years of coaching, level of baseball-playing experience, personal experience with verbal/physical abuse by former coaches, satisfaction with athletes' attitudes, number of athletes on the team, team competition level, awareness of the recommendations of the Japanese Society of Clinical Sports Medicine, limitations in the total pitch count, difficulty in coaching in other positions, number of games per year, and acceptance of former verbal/physical abuse., Results: The prevalence of verbal/physical abuse toward young athletes was 74.5% (n = 283) and 6.6% (n = 25), respectively. Verbal abuse was significantly associated with personal experience of verbal abuse by former coaches (odds ratio [OR]: 2.00, 95% confidence interval [95% CI]: 1.04-3.85), and acceptance of verbal/physical abuse (OR: 2.61, 95% CI: 1.34-5.10). Physical abuse was significantly associated with greater than 10 years of coaching experience (OR: 7.16, 95% CI: 1.36-37.78), personal experience with physical abuse by former coaches (OR: 4.25, 95% CI: 1.23-14.70), and acceptance of verbal/physical abuse (OR: 3.85, 95% CI: 1.51-9.84)., Conclusions: Coaches' experiences with verbal/physical abuse by former coaches negatively affected young athletes. Breaking this cycle is necessary to keep athletes active and interested in playing baseball., Level of Evidence: Level III., (Copyright © 2018 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

High temperature reduces influenza viral replication; however, the treatment of fevers is thought to be necessary to improve patients' conditions. We examined the effects of high temperature on viral replication and infection-induced damage to human tracheal epithelial cells. Cell viability and dome formation were reduced, the number of detached cells was increased and lactate dehydrogenase (LDH) levels tended to be increased from 72 h to 120 h in uninfected cells cultured at 40 °C. Long-term (72 h and/or 120 h) exposure to high temperatures (39 °C and/or 40 °C) decreased RNA levels and/or viral titers of eight influenza virus strains. Cell viability and dome formation were reduced, and the number of detached cells and LDH levels were increased to a similar extent after infection with the A/H1N1 pdm 2009 virus at 37 °C and 40 °C. High temperature increased the endosomal pH, where the viral RNA enters the cytoplasm, in uninfected cells. High temperature reduced the production of IL-6, which mediate viral replication processes, and IL-1β and IL-8 in uninfected and infected cells. Based on these findings, high temperature may cause similar levels of airway cell damage after infection to cells exposed normal temperatures, although high temperature reduces viral replication by affecting the function of acidic endosomes and inhibiting IL-6-mediated processes.

Adult muscle stem cells (satellite cells) are required for adult skeletal muscle regeneration. A proper balance between quiescence, proliferation, and differentiation is essential for the maintenance of the satellite cell pool and their regenerative function. Although the ubiquitin-proteasome is required for most protein degradation in mammalian cells, how its dysfunction affects tissue stem cells remains unclear. Here, we investigated the function of the proteasome in satellite cells using mice lacking the crucial proteasomal component, Rpt3. Ablation of Rpt3 in satellite cells decreased proteasome activity. Proteasome dysfunction in Rpt3-deficient satellite cells impaired their ability to proliferate, survive and differentiate, resulting in defective muscle regeneration. We found that inactivation of proteasomal activity induced proliferation defects and apoptosis in satellite cells. Mechanistically, insufficient proteasomal activity upregulated the p53 pathway, which caused cell-cycle arrest. Our findings delineate a critical function of the proteasome system in maintaining satellite cells in adult muscle., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: There is scarce epidemiological evidence regarding the relationships of the consumption of different types of vegetables or fruits with change in skeletal muscle strength. We prospectively examined the relationships among Japanese adults, using handgrip strength to assess skeletal muscle strength., Methods: A 3-year study was carried out with 259 Japanese adults who were 22-68 years of age. The frequency of consumption of different types of vegetables or fruits were obtained using a validated self-administered dietary history questionnaire. Handgrip strength was measured with a handheld digital Smedley dynamometer., Results: After adjustment for confounding factors, the mean change in handgrip strength in participants stratified according to the level of tomato and tomato product consumption at baseline were -3.2 (95% confidence interval [CI], -4.0 to -2.3) for <1 time/week, -2.7 (95% CI, -3.6 to -1.8) for 1 time/week, -1.6 (95% CI, -2.5 to -0.8) for 2-3 times/week, and -1.7 (95% CI, -2.8 to -0.7) for ≥4 times/week, (P for trend = 0.022). However, the significant relationships of consumption of other types of vegetables and different types of fruits with change in handgrip strength were not observed., Conclusion: Higher consumption of tomato and tomato product at baseline was significantly associated with reduced decline in handgrip strength among Japanese adults over a 3-year follow-up period. This study suggests that consumption of tomato and tomato product could be protective against the decline in skeletal muscle strength associated with aging.