Clinical characteristics and prognosis of patients with incidentally discovered chest wall sarcoma compared with those of symptomatic patients.

OBJECTIVE: Sarcomas of the bone and soft tissues are detected after the onset of pain, detectable mass and related symptoms in the absence of a standardized screening examination. However, primary chest wall sarcomas can be incidentally detected upon chest X-ray or computed tomography. Previous studies of incidental primary chest wall sarcomas lack prognosis and disease-specific clinical data. This study aimed to investigate the prognoses of patients with incidental chest wall sarcomas and compare them with those of symptomatic patients. METHODS: This study included 18 patients diagnosed with primary chest wall sarcoma between 2010 and 2023. Patient information such as age, sex, tumour diameter, tumour location, symptoms, treatment, time to treatment initiation, pathological diagnosis and outcome were retrospectively analysed. RESULTS: Among the 18 patients, the sarcomas were incidentally detected in five by chest X-ray and computed tomography in three and two patients, respectively. The pathological diagnoses of the patients were Ewing sarcoma, Chondrosarcoma grade 1, grade 2, periosteal osteosarcoma and malignant peripheral nerve sheath tumour. The patients had no symptoms at the first visit to our hospital, and no lesions in other organs were detected at the time of the initial examination. At the final follow-up, the patients remained disease-free after radical treatment. The tumour sizes of the five patients were significantly smaller than those of patients with symptoms (P = 0.003). CONCLUSIONS: The incidental detection of chest wall sarcomas and consequent early detection and treatment of tumours improves patient prognosis relative to that of symptomatically diagnosed patients.

The 5-Year Course of Neck Pain Among Natural Disaster Survivors: The Association of Prior Neck Pain with New Episodes of Neck Pain.

OBJECTIVE: Neck pain is a common health problem among both the general population and natural disaster survivors. However, the long-term course of neck pain has rarely been reported. The aim of this study was to elucidate the 5-year course of neck pain among survivors of the Great East Japan Earthquake (GEJE) by assessing the association of neck pain 2 and 4 years after the disaster with that at 7 years. STUDY DESIGN: Longitudinal study. METHODS: A panel study was conducted on GEJE survivors (n = 1,821) through the administration of a self-reported questionnaire at 2 (first time point), 4 (second time point), and 7 years (third time point) after the disaster. Multivariate logistic regression analyses were performed to assess the association between prior neck pain and subsequent neck pain. RESULTS: The rates of neck pain at the first, second, and third time points were 20.7%, 21.1%, and 20.1%, respectively. Neck pain at the first time point was significantly associated with neck pain at the third time point (adjusted odds ratio [95% confidence interval]: 5.96 [4.53-7.83]). Furthermore, neck pain at the first and second time points was significantly associated with neck pain at the third time point (adjusted odds ratio [95% confidence interval]: 5.71 [4.19-7.78] for neck pain at either time point; 15.94 [10.99-23.12] for neck pain at both time points; P for trend <0.001). CONCLUSIONS: Prior neck pain was significantly associated with neck pain 5 years later, and the effect was stronger with an increase of prior neck pain episodes. Clinicians should base their selection of treatment method on an individual's history of neck pain.

Sleep disturbance is associated with neck pain: a 3-year longitudinal study after the Great East Japan Earthquake.

BACKGROUND: Neck pain is a common health problem in the general population as well as in people after natural disasters. Sleep disturbances are gaining attention as risk factors for musculoskeletal pain; however, the association between sleep disturbance and neck pain has not been clarified. The present study aimed to clarify the association between sleep disturbance and neck pain, especially focusing on the effect of the duration of sleep disturbance, after the Great East Japan Earthquake. METHODS: This study used 3-year longitudinal data obtained from individuals (n = 2,059) living in disaster-affected areas after the Great East Japan Earthquake. Sleep disturbance and neck pain were investigated at 4, 5, 6, and 7 years after the disaster. Multivariate logistic regression analyses were used for the assessment. RESULTS: Sleep disturbance was significantly associated with neck pain, and the association was stronger as the duration of sleep disturbance increased (adjusted odds ratios [95% confidence intervals]: 1.84 [1.23-2.75] for " < 1 year"; 2.41 [1.53-3.81] for " ≥ 1 year and < 2 years"; 2.80 [2.09-3.76] for " ≥ 2 years"). Furthermore, preceding sleep disturbance was significantly associated with the onset of neck pain, and the association was stronger as the duration of sleep disturbance increased (adjusted odds ratios [95% confidence intervals]: 1.86 [1.08-3.20] for " < 1 year"; 2.39 [1.22-4.70] for " ≥ 1 year and < 2 years"; 3.00 [1.94-4.65] for " ≥ 2 years"). CONCLUSIONS: Sleep disturbance is associated with neck pain, and long-lasting sleep disturbance strengthens the association. Clinicians should consider this association to effectively treat patients with neck pain, especially those affected by natural disasters.

Characteristics of Parents Who Feel a Lack of Communication with Coaches of Youth Sports.

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.

Contracted joint capsule affects labral and chondral lesions in patients with frozen shoulder.

PURPOSE: Intra-articular pathologies, such as labral and chondral lesions, are common in patients with frozen shoulder. This study evaluated the correlations between the range of motion and labral and chondral lesions in patients with frozen shoulder and investigated their pathophysiologies. METHODS: In total, 125 individuals (53 men and 72 women) who underwent arthroscopic pan-capsular release between 2014 and 2020 were included in the study. The range of motion was measured using scapular fixation and true glenohumeral motion under general anaesthesia. The American Shoulder and Elbow Surgeons Shoulder score and the Shoulder Rating Scale score of the University of California, Los Angeles were used to compare intra-articular pathologies. RESULTS: More than 80% of patients with frozen shoulder had labral pathologies, and nearly half of them had chondral pathologies. Labral lesions extending to the anterior rim of the glenoid had a greater range of motion and the greatest total American Shoulder and Elbow Surgeons Shoulder score. More severe chondral lesions had a lesser range of motion, but presented the greatest function scores and the lowest strength scores according to the Shoulder Rating Scale of the University of California, Los Angeles. The pain scores of the American Shoulder and Elbow Surgeons Shoulder score and the Shoulder Rating Scale of the University of California, Los Angeles were not correlated with the degree of these pathologies. The traction force affected the labrum during true range of motion, and the compression force occurred on the articular cartilage during internal rotation at 90° of forward flexion during diagnostic arthroscopy. CONCLUSION: Labral and chondral lesions are common in patients with frozen shoulder. Adherence to the capsulolabral complex induced a limited range of motion and labral and chondral pathologies. Diagnostic arthroscopy with motion is an important method of reproducing the pathogenesis of intra-articular structures for patients with frozen shoulder. LEVEL OF EVIDENCE: Level III.

Musculoskeletal pain in other body sites is associated with new-onset low back pain: a longitudinal study among survivors of the great East Japan earthquake.

BACKGROUND: Low back pain (LBP) is a common health problem experienced after natural disasters. LBP is often concurrent with other musculoskeletal pain; however, the effects of preexisting musculoskeletal pain on the development of LBP are not clear. The purpose of this study was to elucidate the association of musculoskeletal pain in other body sites with new-onset LBP among survivors of the Great East Japan Earthquake (GEJE). METHODS: A longitudinal study was conducted with survivors of the GEJE. The survivors who did not have LBP at the 3 year time period after the GEJE were followed up 1 year later (n = 1782). Musculoskeletal pain, such as low back, hand and/or foot, knee, shoulder, and neck pain, were assessed with self-reported questionnaires. The outcome of interest was new-onset LBP, which was defined as LBP absent at 3 years but present at 4 years after the disaster. The main predictor was musculoskeletal pain in other body sites 3 years after the GEJE, which was categorized according to the number of pain sites (0, 1, ≥ 2). Multiple regression analyses were performed to calculate the odds ratio (OR) and 95% confidence interval (CI) for new-onset LBP due to musculoskeletal pain in other body sites. RESULTS: The incidence of new-onset LBP was 14.1% (251/1782). Musculoskeletal pain in other body sites was significantly associated with new-onset LBP. Including people without other musculoskeletal pain as a reference, the adjusted OR and 95% CI for new-onset LBP were 1.73 (1.16-2.57) for people with one musculoskeletal pain site and 3.20 (2.01-5.09) for people with ≥ 2 sites (p <  0.001). CONCLUSIONS: Preexisting musculoskeletal pain in other body sites was associated with new-onset LBP among survivors in the recovery period after the GEJE.

Low Back Pain in School-Aged Martial Arts Athletes in Japan: A Comparison among Judo, Kendo, and Karate.

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.

Upper Extremity Pain Is Associated with Lower Back Pain among Young Basketball Players: A Cross-Sectional Study.

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.

Preceding Poor Physical Function Is Associated with New-Onset Musculoskeletal Pain among Older Natural Disaster Survivors: A Longitudinal Study after the Great East Japan Earthquake.

Musculoskeletal pain is a major problem among survivors of natural disasters. Functional disabilities in older adults increase after disasters and can lead to musculoskeletal pain. However, the effects of poor physical function on musculoskeletal pain after natural disasters remain unclear. This study aimed to elucidate the association of poor physical function with new-onset musculoskeletal pain among older survivors after the Great East Japan Earthquake (GEJE). Survivors aged ≥ 65 years, 3 years after the GEJE, were assessed longitudinally for 1 year (n = 646). Musculoskeletal pain was assessed using a self-reported questionnaire, and new-onset musculoskeletal pain was defined as absence and presence of pain at 3 years and 4 years, respectively, after the disaster. Physical function at 3 years after the disaster was assessed using the Kihon Checklist physical function score, which consists of 5 yes/no questions, and poor physical function was defined as a score of ≥ 3/5. Multivariate logistic regression analyses were used to assess the association of poor physical function with new-onset musculoskeletal pain. The incidence of new-onset musculoskeletal pain was 22.4%. Participants with poor physical function had a significantly higher rate of new-onset musculoskeletal pain. Compared with high physical function, the adjusted odds ratio (95% confidence interval) for new-onset musculoskeletal pain was 2.25 (1.37-3.69) in poor physical function (P = 0.001). Preceding poor physical function was associated with new-onset musculoskeletal pain among older survivors after the GEJE. There is need to focus on the maintenance of physical function to prevent musculoskeletal pain after natural disasters.

Musculoskeletal pain and new-onset poor physical function in elderly survivors of a natural disaster: a longitudinal study after the great East Japan earthquake.

BACKGROUND: Functional disability is a significant problem after natural disasters. Musculoskeletal pain is reported to increase after disasters, which can cause functional disability among survivors. However, the effects of musculoskeletal pain on functional decline after natural disasters are unclear. The present study aimed to examine the association between musculoskeletal pain and new-onset poor physical function among elderly survivors after the Great East Japan Earthquake. METHODS: A longitudinal study was conducted on survivors aged ≥65 years at three and 4 years after the Great East Japan Earthquake. A total of 747 persons were included in this study. Physical function was assessed using the Kihon Checklist. New-onset poor physical function was defined as low physical function not present at 3 years but present at 4 years after the disaster. Knee, hand or foot, low back, shoulder, and neck pain was assessed using a self-reported questionnaire and was defined as musculoskeletal pain. Musculoskeletal pain at 3 years after the disaster was categorized according to the number of pain regions (0, 1, ≥ 2). Multiple logistic regression analyses were performed to calculate the odds ratio (OR) and 95% confidence interval (95% CI) for new-onset poor physical function due to musculoskeletal pain. RESULTS: The incidence of new-onset poor physical function was 14.9%. New-onset poor physical function was significantly associated with musculoskeletal pain. Compared with "0" musculoskeletal pain region, the adjusted ORs (95% CI) were 1.39 (0.75-2.58) and 2.69 (1.52-4.77) in "1" and "≥ 2" musculoskeletal pain regions, respectively (p for trend = 0.003). CONCLUSIONS: Musculoskeletal pain is associated with new-onset poor physical function among elderly survivors after the Great East Japan Earthquake. Monitoring musculoskeletal pain is important to prevent physical function decline after natural disasters.

Parents' Own Experience of Verbal Abuse Is Associated with their Acceptance of Abuse towards Children from Youth Sports Coaches.

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.

Verbal Abuse from Coaches Is Associated with Loss of Motivation for the Present Sport in Young Athletes: A Cross-Sectional Study in Miyagi Prefecture.

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.

Knee pain is associated with lower back pain in young baseball players: a cross-sectional study.

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.

Involvement of neutrophils and interleukin-18 in nociception in a mouse model of muscle pain.

Muscle pain is a common condition that relates to various pathologies. Muscle overuse induces muscle pain, and neutrophils are key players in pain production. Neutrophils also play a central role in chronic pain by secreting interleukin (IL)-18. The aim of this study was to investigate the involvement of neutrophils and IL-18 in a mouse model of muscle pain. The right hind leg muscles of BALB/c mice were stimulated electrically to induce excessive muscle contraction. The left hind leg muscles were not stimulated. The pressure pain threshold, number of neutrophils, and IL-18 levels were investigated. Furthermore, the effects of the IL-18-binding protein and Brilliant Blue G on pain were investigated. In stimulated muscles, pressure pain thresholds decreased, and neutrophil and IL-18 levels increased compared with that in non-stimulated muscles. The administration of IL-18-binding protein and Brilliant Blue G attenuated hyperalgesia caused by excessive muscle contraction. These results suggest that increased IL-18 secretion from larger numbers of neutrophils elicits mechanical hyperalgesia.

Roles of IL-1α/ß in regeneration of cardiotoxin-injured muscle and satellite cell function.

Skeletal muscle regeneration after injury is a complex process involving interactions between inflammatory microenvironments and satellite cells. Interleukin (IL)-1 is a key mediator of inflammatory responses and exerts pleiotropic impacts on various cell types. Thus, we aimed to investigate the role of IL-1 during skeletal muscle regeneration. We herein show that IL-1α/ß-double knockout (IL-1KO) mice exhibit delayed muscle regeneration after cardiotoxin (CTX) injection, characterized by delayed infiltrations of immune cells accompanied by suppressed local production of proinflammatory factors including IL-6 and delayed increase of paired box 7 (PAX7)-positive satellite cells postinjury compared with those of wild-type (WT) mice. A series of in vitro experiments using satellite cells obtained from the IL-1KO mice unexpectedly revealed that IL-1KO myoblasts have impairments in terms of both proliferation and differentiation, both of which were reversed by exogenous IL-1ß administration in culture. Intriguingly, the delay in myogenesis was not attributable to the myogenic transcriptional program since MyoD and myogenin were highly upregulated in IL-1KO cells, instead appearing, at least in part, to be due to dysregulation of cellular fusion events, possibly resulting from aberrant actin regulatory systems. We conclude that IL-1 plays a positive role in muscle regeneration by coordinating the initial interactions among inflammatory microenvironments and satellite cells. Our findings also provide compelling evidence that IL-1 is intimately engaged in regulating the fundamental function of myocytes.

Sleep Disturbance Is Associated with New Onset and Continuation of Lower Back Pain: A Longitudinal Study among Survivors of the Great East Japan Earthquake.

Lower back pain (LBP) is a common health problem after natural disasters. Although some related factors have been reported, the effect of sleep disturbances on LBP is not clear. The purpose of this study was to elucidate the influence of sleep disturbances on LBP after the Great East Japan earthquake (GEJE). A panel study was conducted with the survivors of the GEJE (n = 2,295) at three and four years after the disaster using self-reported questionnaires. The changes in the presence of LBP during the two periods were assessed; LBP was characterized as either new onset or continuation of LBP. The participants' sleep conditions were assessed, and the changes in sleep disturbances during the two periods were classified into four groups: absence, new onset, improvement, and continuation. Multivariate logistic regression models were used to analyze the association of the changes in sleep disturbance with new onset and continuation of LBP. The rates of new onset and continuation of LBP were 14.1% and 55.1%, respectively. The changes in sleep disturbances were significantly associated with new-onset and continuing LBP. Using "absence" as a reference for the change of sleep disturbance, the adjusted ORs (95% CI) for new-onset LBP were 2.19 (1.42-3.38) in "new onset," 1.38 (0.83-2.30) in "improvement," and 2.17 (1.50-3.15) in "continuation," and those for continuing LBP were 1.42 (0.71-2.84) in "new onset," 0.98 (0.55-1.74) in "improvement," and 1.60 (1.01-2.51) in "continuation." Careful attention should be paid to sleep disturbances to prevent and improve LBP after natural disasters.

CIC-DUX4 Rearranged Sarcoma Presenting in the Skin: Case Report.

Introduction: Capicua transcriptional repressor (CIC)-DUX4 rearranged sarcoma is a subtype of CIC-rearranged sarcomas composed of undifferentiated Wilms' tumor 1 (WT1)+, CD99+ round cells with recurrent CIC gene rearrangement. The diagnosis of CIC-rearranged sarcoma remains challenging, and the prognosis of CIC-rearranged sarcomas is poor. Case Presentation: In this report, we described a case of CIC-DUX4 rearranged sarcoma presenting in the skin, expressing WT1 and CD99 in a dot-like pattern. In addition, the assessment of genomic alterations using genome panel testing was useful to confirm the accurate diagnosis. Conclusion: Our present case suggests that widespread use of genomic panel testing in the future may lead to early treatment and improve the prognosis of CIC-rearranged sarcomas.

Involvement of the apelin receptor APJ in Fas-induced liver injury.

BACKGROUND: Apelin-APJ signalling is known to play important roles in heart physiology and pathology; however, its functions in liver physiology and pathology remain unclear. On the other hand, Fas is an important molecule in hepatitis and other liver disease that belongs to the death receptor family. The aim of this study was to assess the relationship between apelin-APJ signaling and Fas-mediated liver injury in mice. METHODS: APJ(-/-) mice and wild type (WT) mice were administered an intraperitoneal injection of an agonistic anti-Fas antibody (clone; Jo2), and sacrificed after 3 or 6 h to assess the liver histology. The expression levels of apelin and APJ, plasma levels of transaminases, activities of hepatic caspases and activations of stress-activated protein kinases were also analysed. RESULTS: Before the Jo2 injection, APJ was weakly expressed in the hepatocytes in spots; on the other hand, after the Jo2 injection, it had spread into whole hepatocytes. Moreover, the mRNA expression level of apelin and APJ in the liver increased after Jo2 injection. In the APJ(-/-) mice, the liver injuries and apoptotic changes were significantly inhibited as compared with those in the WT mice. Dramatic increase in JNK activation was observed in the WT mice after Jo2 injection, whereas such activation was completely absent in the APJ(-/-) mice. JNK inhibitor partially, but significantly suppressed Jo2-mediated liver injury in WT mice. CONCLUSION: Apelin-APJ signalling may promote Fas-induced liver injury at least partially via JNK activation, and may thus serve as a potential therapeutic target in cases of acute liver injury.

Knee pain in young sports players aged 6-15 years: a cross-sectional study in Japan.

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.