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BACKGROUND: In soccer, the roles of the dominant (kicking) and nondominant (supporting) legs are different. The kinematic differences between the actions of the dominant and nondominant legs in female soccer players are not clear. PURPOSE: To clarify the kinematic differences between dominant and nondominant legs during a single-leg drop vertical jump (DVJ) in female soccer players. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 64 female high school and college soccer players were included in this study. Participants performed a single-leg DVJ test utilizing video motion capture with artificial intelligence during the preseason period. This study assessed the knee flexion angles, knee valgus angles, hip flexion angles, and lower leg anterior inclination angle at 3 time points (initial contact, maximum flexion of the knee, and toe-off) and compared them between the dominant and nondominant legs. These angles were calculated from motion capture data and analyzed in 3 dimensions. A paired t test was used to analyze the differences between legs, and the significance level was set at P < .05. RESULTS: The knee valgus angle at initial contact was greater in the nondominant leg (mean ± SD, 0.8°± 5.2°) than the dominant leg (-0.9°± 4.9°) (P < .01). There were no differences between legs for any other angles at any of the time points. CONCLUSION: The kinematics of the dominant and nondominant legs of female soccer players in a single-leg DVJ differ in knee valgus angle. CLINICAL RELEVANCE: Leg dominance is associated with the risk of sports injuries. Kinematic differences between the dominant and nondominant legs may be a noteworthy factor in elucidating the mechanisms and risk of sports injury associated with leg dominance.

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Among the various elements that facilitate the movement of the lower limbs, the anterior cruciate ligament (ACL) is prone to injury. An adequate joint control of the lower limb can prevent ACL injury. Balancing activities between the agonist and the antagonist muscles is vital for joint control. However, prior studies on muscle activities were limited since they could not determine passive muscle activities. In this study, we develop a muscle model considering the passive properties to analyze the movement mechanism of the ACL under heavy loads, such as those produced during jump landing. We estimated the muscle activities occurring during a drop vertical jump (DVJ) by applying to the proposed method the physiological constraint that muscle activities are constant during a short time around landing. In addition, the knee joint torque and muscle forces were calculated from the estimated muscle activities, which were thereafter compared with those obtained using the conventional method. The results revealed that this passive muscle model appropriately represented the knee joint torque at DVJ landing by decreasing the passive muscle strain and increasing the isometric maximum muscle force. Moreover, the estimated muscle activities were larger than those obtained using the conventional method, which may be caused by the co-contraction between agonist and antagonist muscles that cannot be represented by the conventional method. This muscle co-contraction estimation algorithm would estimate the muscle load under heavy loads, and applying this knowledge to training would help to prevent ACL injuries.

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BACKGROUND: Sex-based biomechanical differences during a drop vertical jump (DVJ) may explain the increased risk of anterior cruciate ligament injury in females. Video motion capture using artificial intelligence (VMocap) is a new method for accurate motion analysis. PURPOSE: To use VMocap to identify sex-based differences in biomechanics during a DVJ in Asian athletes. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 63 female and 61 male Asian soccer players volunteered for this study in 2018. Participants performed a bilateral DVJ using VMocap, and the knee valgus angle (KVA), knee flexion angle (KFA), hip flexion angle (HFA), and lower leg anterior inclination angle (LAIA) were calculated from the motion capture data. These joint angles and inclination angles were evaluated at the time of highest point of the first jump (H1), initial contact (IC), maximum knee flexion (MKF), toe-off (TO), and highest point of the second jump (H2). The unpaired t test was used to compare sex-based differences. RESULTS: At H1, the KVA in females showed more valgus (-2.9° vs -5.4°) and the LAIA in females was greater (29.1° vs 25.7°) versus males (P < .01 for both). At IC, the KVA in females showed more valgus (-1.3° vs -3.0°) and females had a greater KFA (20.8° vs 14.3°) and LAIA (5.1° vs 0.0°) compared with males (P < .01 for all). At MKF, female KVA showed more valgus (6.2° vs -9.5°), and females had greater LAIA (36.6° vs 34.6°), smaller KFA (77.5° vs 87.5°), and smaller HFA (55.8° vs 82.0°) compared with males (P < .01 for all). At TO, female KVA showed more valgus (-0.7° vs -3.1°) and female KFA, HFA, and LAIA were greater (31.7° vs 19.2°; 19.9° vs 16.4°; and 18.2° vs 11.5°, respectively) than males (P < .01 for all). At H2, females had a greater KFA (18.6° vs 14.6°) and LAIA (13.3° vs 9.9°) than males (P < .04 for both). CONCLUSION: Asian female soccer players showed increased KVA and LAIA, decreased KFA and HFA at MKF, and increased KFA at IC and TO compared with their male counterparts in this analysis of the DVJ. CLINICAL RELEVANCE: Elucidation of kinematic differences between the sexes can aid in predicting injuries.

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In this paper, we propose the analysis method for finding out the similarity of the muscle force patterns to mine the risk factor of the anterior cruciate ligament (ACL) injury. Akaike information criteria (AIC) under the assumption of the auto-regression model is adapted to analyze the similarities of muscle force patterns in time-series. The difference of AIC values between 2 muscles is considered to be the distance between 2 muscle force patterns and the dexterity of the maneuver is expected to be discussed. We measured drop vertical jump (DVJ) and use the data around the contact timing of whom hadn't had ACL injury experiments. The results showed that we could successfully calculate AIC distance according to the similarity of the time-series data pattern and it can be useful to discuss one's dexterity of controlling body maneuvers soon after contact timing of DVJ motion.

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AIM: To identify environmental and physical factors that predispose middle-aged and older Japanese adults to falls and fall-related fractures in the home. METHODS: A cross-sectional survey was carried out in 2014. Self-administered questionnaires were distributed to 15 000 community-dwelling adults in Japan. The overall crude response rate was 13%. Response data were analyzed from 1561 individuals aged ≥40 years using multiple imputation to analyze missing data. We evaluated falls without fractures and fall-related fractures during the previous 3 years according to demographic, physical and environmental factors, including age, sex, long-term care insurance certification, type of house and barrier-free housing. RESULTS: Of the 1561 adults (mean age 68.1 ± 13.0 years), 28% experienced a fall in the home. Among the individuals who experienced a fall, 11% experienced fall-related fractures. These individuals were more likely to be women (OR 2.4, 95.0% CI 1.1-5.1), have LTCI certification (OR 3.9, 95.0% CI 1.6-9.4) and be living in a barrier home (OR 4.0, 95.0% CI 1.6-9.8), after adjustment for covariates. CONCLUSIONS: Environmental factors, such as living in a barrier home, are critical for fall-related fractures, in addition to demographic and physical factors. A multidisciplinary approach that considers both physical and environmental factors is necessary for reducing the incidence of fall-related fractures among middle-aged and older Japanese adults. Geriatr Gerontol Int 2018; 18: 1372-1377.

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Six lanostane-type triterpene acids (1a-6a), isolated from Poria cocos , and their methyl ester (1b-6b) and hydroxy derivatives (1c-6c) were prepared. Upon evaluation of the cytotoxic activity of these compounds against leukemia (HL60), lung (A549), melanoma (CRL1579), ovary (NIH:OVCAR-3), breast (SK-BR-3), prostate (DU145), stomach (AZ521), and pancreas (PANC-1) cancer cell lines, 11 compounds (5a, 6a, 2b-5b, 1c, and 3c-6c) exhibited activity with single-digit micromolar IC(50) values against one or more cell lines. Poricotriol A (1c), a hydroxy derivative of poricoic acid A (1a), exhibited potent cytotoxicities against six cell lines with IC(50) values of 1.2-5.5 µM. Poricotriol A induced typical apoptotic cell death in HL60 and A549 cells on evaluation of the apoptosis-inducing activity by flow cytometric analysis. Western blot analysis in HL60 cells showed that poricotriol A activated caspases-3, -8, and -9, while increasing the ratio of Bax/Bcl-2. This suggested that poricotriol A induced apoptosis via both mitochondrial and death receptor pathways in HL60. On the other hand, poricotriol A did not activate caspases-3, -8, and -9, but induced translocation of apoptosis-inducing factor (AIF) from mitochondria and increased the ratio of Bax/Bcl-2 in A549. This suggested that poricotriol A induced apoptosis via the mitochondrial pathway mostly by translocation of AIF, independent from the caspase pathway in A549. Furthermore, poricotriol A was shown to possess high selective toxicity in lung cancer cells since it exhibited only weak cytotoxicity against a normal lung cell line (WI-38).

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Nine new (1, 3, 5, 8, 12, 13, 15, 17, and 18) and nine known (2, 4, 6, 7, 9-11, 14, and 16) lanostane-type triterpene acids and a known diterpene acid (19) were isolated from the epidermis of the sclerotia of Poria cocos. The structures of the new compounds were established as 16alpha,27-dihydroxydehyrotrametenoic acid (1), 25-hydroxy-3-epitumulosic acid (3), 16alpha,25-dihydroxyeburiconic acid (5), 25-methoxyporicoic acid A (8), 26-hydroxyporicoic acid DM (12), 25-hydroxyporicoic acid C (13), poricoic acid GM (15), poricoic acid HM (17), and 6,7-dehydroporicoic acid H (18), on the basis of spectroscopic methods. On evaluation of the nine new and two of the known compounds, 4 and 19, against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, all of the compounds exhibited inhibitory effects, with IC(50) values in the range 187-348 mol ratio/32 pmol TPA. In addition, compound 8 exhibited an inhibitory effect on skin tumor promotion in an in vivo two-stage carcinogenesis test using 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter. Further, 17 compounds, 1-14, 16, 18, and 19, were evaluated for their cytotoxic activity against two human tumor cell lines, HL60 (leukemia) and CRL1579 (melanoma).

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The structures of six new lanostane-type triterpene acids isolated from the epidermis of the sclerotia of Poria cocos were established to be 15alpha-hydroxydehydrotumulosic acid (5), 16alpha,25-dihydroxydehydroeburicoic acid (9), 5alpha,8alpha-peroxydehydrotumulosic acid (10), 25-hydroxyporicoic acid H (11), 16-deoxyporicoic acid B (12), and poricoic acid CM (16) on the basis of spectroscopic methods. On evaluation of these six and 11 other known triterpene acids isolated from the sclerotium, 1-4, 6-8, 13-15, and 17, against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, all of the compounds except for 1, 3, 4, and 8 exhibited inhibitory effects with IC50 values of 195-340 mol ratio/32 pmol TPA. Compound 12 and poricoic acid C (13) exhibited inhibitory effects on skin tumor promotion in an in vivo two-stage carcinogenesis test using 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter.

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A series of lanostane-type triterpene acids, including eleven lucidenic acids (3, 4, 9, 10, 13-19) and six ganoderic acids (20-22, 24, 26, 27), as well as six sterols (28-33), all isolated from the fruiting bodies of the fungus Ganoderma lucidum, were examined for their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, a known primary screening test for anti-tumor promoters. All of the compounds tested, except for ganolactone (27) and three sterols (29-31), showed potent inhibitory effects on EBV-EA induction, with IC(50) values of 235-370 mol ratio/32 pmol TPA. In addition, nine lucidenic acids (1, 2, 5-8, 11, 12, 18) and four ganoderic acids (20, 23-25) were found to inhibit TPA-induced inflammation (1 microg/ear) in mice, with ID(50) values of 0.07-0.39 mg per ear. Further, 20-hydroxylucidenic acid N (18) exhibited inhibitory effects on skin-tumor promotion in an in vivo two-stage mouse-skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter.

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