16 research outputs found

    The influence of X-factor (trunk rotation) and experience on the quality of the badminton forehand smash

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    Sherpa Romeo green journal. Open access article. Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License 9CC BY-NC-ND 3.0) appliesNo existing studies of badminton technique have used full-body biomechanical modeling based on three dimensional (3D) motion capture to quantify the kinematics of the sport. The purposes of the current study were to: 1) quantitatively describe kinematic characteristics of the forehand smash using a 15-segment, full-body biomechanical model, 2) examine and compare kinematic differences between novice and skilled players with a focus on trunk rotation (the X-factor), and 3) through this comparison, identify principal parameters that contributed to the quality of the skill. Together, these findings have the potential to assist coaches and players in the teaching and learning of the forehand smash. Twenty-four participants were divided into two groups (novice, n = 10 and skilled, n = 14). A 10-camera VICON MX40 motion capture system (200 frames/s) was used to quantify full-body kinematics, racket movement and the flight of the shuttlecock. Results confirmed that skilled players utilized more trunk rotation than novices. In two ways, trunk rotation (the X-factor) was shown to be vital for maximizing the release speed of the shuttlecock – an important measure of the quality of the forehand smash. First, more trunk rotation invoked greater lengthening in the pectoralis major (PM) during the preparation phase of the stroke which helped generate an explosive muscle contraction. Second, larger range of motion (ROM) induced by trunk rotation facilitated a whip-like (proximal to distal) control sequence among the body segments responsible for increasing racket speed. These results suggest that training intended to increase the efficacy of this skill needs to focus on how the X-factor is incorporated into the kinematic chain of the arm and the racket.Ye

    Terrain or climate factor dominates vegetation resilience? Evidence from three national parks across different climatic zones in China

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    Vegetation resilience (VR), providing an objective measure of ecosystem health, has received considerable attention, however, there is still limited understanding of whether the dominant factors differ across different climate zones. We took the three national parks (Hainan Tropical Rainforest National Park, HTR; Wuyishan National Park, WYS; and Northeast Tiger and Leopard National Park, NTL) of China with less human interference as cases, which are distributed in different climatic zones, including tropical, subtropical and temperate monsoon climates, respectively. Then, we employed the probabilistic decay method to explore the spatio-temporal changes in the VR and their natural driving patterns using Geographically Weighted Regression (GWR) model as well. The results revealed that: (1) from 2000 to 2020, the Normalized Difference Vegetation Index (NDVI) of the three national parks fluctuated between 0.800 and 0.960, exhibiting an overall upward trend, with the mean NDVI of NTL (0.923) ​> ​HTR (0.899) ​> ​WYS (0.823); (2) the positive trend decay time of vegetation exceeded that of negative trend, indicating vegetation gradual recovery of the three national parks since 2012; (3) the VR of HTR was primarily influenced by elevation, aspect, average ​annual temperature change (AATC), and average annual precipitation change (AAPC); the WYS’ VR was mainly affected by elevation, average ​annual precipitation (AAP), and AAPC; while the terrain factors (elevation and slope) were the main driving factors of VR in NTL; (4) among the main factors influencing the VR changes, the AAPC had the highest proportion in HTR (66.7%), and the AAP occupied the largest area proportion in WYS (80.4%). While in NTL, elevation served as the main driving factor for the VR, encompassing 64.2% of its area. Consequently, our findings indicated that precipitation factors were the main driving force for the VR changes in HTR and WYS national parks, while elevation was the main factors that drove the VR in NTL. Our research has promoted a deeper understanding of the driving mechanism behind the VR

    Both gene deletion and promoter hyper-methylation contribute to the down-regulation of ZAC/PLAGL1 gene in gastric adenocarcinomas: A case control study

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    Background and objective: Pleiomorphic adenoma gene-like 1 (PLAGL1, also known as LOT1 and ZAC) is a zinc-finger nuclear transcription factor, which possesses antiproliferative effects and is frequently epigenetically silenced during tumorigenesis. PLAGL1 gene is located on 6q24-25, a chromosomal region that is frequently deleted in various kinds of cancers. Both promoter hyper-methylation and loss of heterozygosity may lead to the down-regulation of PLAGL1 in human somatic cancers. Here we aimed to investigate the abnormalities of PLAGL1 in gastric cancers. Methods: We collected 153 case-matched gastric adenocarcinoma (GAC) cases. Quantitative real-time PCR method was applied to evaluate the expression levels as well as gene copy numbers of PLAGL1 in the collected samples. Methylation-specific PCR (MSP) assay was performed to analyze the methylation status of PLAGL1 P1 promoter. Results: Decreased expression of PLAGL1 mRNA was observed in GAC tissues, especially in advanced GACs. Copy number decrease of PLAGL1 gene in GACs was observed in 9.15% (19 out of 153) of the GAC samples and was closely correlated with gene expression. Methylation status of PLAGL1 promoter in GAC tissues was higher than in normal controls, which was inversely correlated with the expression levels of PLAGL1 mRNA. Conclusion: DNA deletion and promoter hyper-methylation both contribute to the downregulation of PLAGL1 in GACs. (C) 2013 Published by Elsevier Masson SAS

    Generation of induced pluripotent stem cell line (ZZUi0012-A) from a patient with Fahr's disease caused by a novel mutation in SLC20A2 gene

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    Several SLC20A2 mutations have been implicated as potential causes of Fahr's disease, a subtype of primary familial brain calcification (PFBC), but very few patient-derived induced pluripotent stem cell (iPSC) models have been established. We have identified a novel SLC20A2 mutation in a family with Fahr's disease. We subsequently obtained dermal fibroblasts from a patient in this family. These fibroblasts were successfully transformed into iPSCs by employing episomal plasmids expressing OCT3/4, SOX2, KLF4, LIN28, and L-MYC. Our approach offers a resource and a platform for further research into the mechanism of Fahr's disease and could facilitate development and screening of pharmaceutical and gene therapies

    Risk Factors for Non-Contact Lower-Limb Injury: A Retrospective Survey in Pediatric-Age Athletes

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    Background: Risk factors for non-contact lower-limb injury in pediatric-age athletes and the effects of lateral dominance in sport (laterally vs. non-laterally dominant sports) on injury have not been investigated. Purpose: To identify risk factors for non-contact lower-limb injury in pediatric-age athletes. Methods: Parents and/or legal guardians of 2269 athletes aged between 6–17 years were recruited. Each participant completed an online questionnaire that contained 10 questions about the athlete’s training and non-contact lower-limb injury in the preceding 12 months. Results: The multivariate logistic regression model determined that lateral dominance in sport (adjusted OR (laterally vs. non-laterally dominant sports), 1.38; 95% CI, 1.10–1.75; p = 0.006), leg preference (adjusted OR (right vs. left-leg preference), 0.71; 95% CI, 0.53–0.95; p = 0.023), increased age (adjusted OR, 1.21; 95% CI, 1.16–1.26; p = 0.000), training intensity (adjusted OR, 1.77; 95% CI, 1.43–2.19; p = 0.000), and training frequency (adjusted OR, 1.36; 95% CI, 1.25–1.48; p = 0.000) were significantly associated with non-contact lower-limb injury in pediatric-age athletes. Length of training (p = 0.396) and sex (p = 0.310) were not associated with a non-contact lower-limb injury. Conclusions: Specializing in laterally dominant sports, left-leg preference, increase in age, training intensity, and training frequency indicated an increased risk of non-contact lower-limb injury in pediatric-age athletes. Future research should take into account exposure time and previous injury.Education, Faculty ofMedicine, Faculty ofExperimental Medicine, Division ofKinesiology, School ofMedicine, Department ofReviewedFacult

    The effect of fatigue on asymmetry between lower limbs in functional performances in elite child taekwondo athletes

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    Background: Inter-limb asymmetry above a certain threshold in functional performance indicates increased injury risk in sports. Fatigue has been found to increase bilateral asymmetry in lower-limb jumping performance among high-school and adult athletes, whereas this impact has not been examined in child athletes. This study aimed to examine the effect of fatigue on inter-limb asymmetry in functional performances in elite Taekwondo athletes aged between 9 and 11 years. Methods: Performance of single-leg jumps, Star Excursion Balance Test (SEBT), and muscle (hamstring and gastrocnemius) flexibility were measured for 13 elite male child Taekwondo athletes (aged 9.85 ± 0.80 years) at both the rested and fatigued states to examine the inter-limb asymmetry. A two-way repeated measures ANOVA was conducted to examine for difference and the interaction between limb (dominant, non-dominant leg) and state (rested, fatigued state) for each test. Paired t test or Wilcoxon signed-rank test was used to compare the asymmetry magnitude at the rested vs. fatigued state for each test, and the variation of performance post fatigue in the dominant vs. non-dominant leg when appropriate. Results: The inter-limb asymmetry in triple-hop distance significantly (p = 0.046) increased with fatigue, whereas the asymmetry significantly (p = 0.004) decreased with fatigue in anterior (ANT) reach distance in SEBT. A significant (p = 0.027) limb by state interaction was shown for posterolateral (PL) reach distance in SEBT, wherein a significant (p = 0.005) bilateral difference was only shown at the rested state. The PL reach distance showed a significantly greater decrease (p = 0.028) post fatigue when using the dominant leg for support compared to using the non-dominant leg. Conclusions: Fatigue significantly impacts inter-limb asymmetry in jump performances and dynamic balance for child athletes, while the variation of inter-limb asymmetry post fatigue may be different across tests. For the purpose of injury prevention, practitioners should consider assessing the inter-limb asymmetry for children at both the rested and fatigued state and be mindful of the fatigue response of each leg in functional tests.Education, Faculty ofOther UBCNon UBCKinesiology, School ofReviewedFacult

    Linc00210 drives Wnt/β-catenin signaling activation and liver tumor progression through CTNNBIP1-dependent manner

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    Abstract Background Liver tumor initiating cells (TICs) have self-renewal and differentiation properties, accounting for tumor initiation, metastasis and drug resistance. Long noncoding RNAs are involved in many physiological and pathological processes, including tumorigenesis. DNA copy number alterations (CNA) participate in tumor formation and progression, while the CNA of lncRNAs and their roles are largely unknown. Methods LncRNA CNA was determined by microarray analyses, realtime PCR and DNA FISH. Liver TICs were enriched by surface marker CD133 and oncosphere formation. TIC self-renewal was analyzed by oncosphere formation, tumor initiation and propagation. CRISPRi and ASO were used for lncRNA loss of function. RNA pulldown, western blot and double FISH were used to identify the interaction between lncRNA and CTNNBIP1. Results Using transcriptome microarray analysis, we identified a frequently amplified long noncoding RNA in liver cancer termed linc00210, which was highly expressed in liver cancer and liver TICs. Linc00210 copy number gain is associated with its high expression in liver cancer and liver TICs. Linc00210 promoted self-renewal and tumor initiating capacity of liver TICs through Wnt/β-catenin signaling. Linc00210 interacted with CTNNBIP1 and blocked its inhibitory role in Wnt/β-catenin activation. Linc00210 silencing cells showed enhanced interaction of β-catenin and CTNNBIP1, and impaired interaction of β-catenin and TCF/LEF components. We also confirmed linc00210 copy number gain using primary hepatocellular carcinoma (HCC) samples, and found the correlation between linc00210 CNA and Wnt/β-catenin activation. Of interest, linc00210, CTNNBIP1 and Wnt/β-catenin signaling targeting can efficiently inhibit tumor growth and progression, and liver TIC propagation. Conclusion With copy-number gain in liver TICs, linc00210 is highly expressed along with liver tumorigenesis. Linc00210 drives the self-renewal and propagation of liver TICs through activating Wnt/β-catenin signaling. Linc00210 interacts with CTNNBIP1 and blocks the combination between CTNNBIP1 and β-catenin, driving the activation of Wnt/β-catenin signaling. Linc00210-CTNNBIP1-Wnt/β-catenin axis can be targeted for liver TIC elimination

    Cepharanthine inhibits influenza A virus replication by impairing viral polymerase activity and regulating influenza-induced immune response

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    Background: Cepharanthine (CEP), a natural bis-benzylisoquinoline alkaloid extracted from the plant Stephania cephalantha Hayata, has been widely used to treat several acute and chronic diseases. However, its antiviral potential against influenza A virus (IAV) infection remains unknown. Purpose: The study aims to assess the antiviral and immunomodulatory effects of CEP in vivo and in vitro and investigate its underlying antiviral mechanisms. Methods: Antiviral and anti-inflammatory activities of CEP were assessed in MDCK, A549 and RAW264.7 cells infected with influenza virus. Proinflammatory cytokine levels were measured by qRT-PCR and ELISA. The anti-influenza effect and underlying antiviral mechanism of CEP were mainly determined by MTT assay, plaque reduction assay, time-of-addition and mini-replicon assay. The inhibition of CEP on IAV-induced activation of innate immune signaling was detected by western blotting. Furthermore, BALB/c mice were infected intranasally with A/PR/8/34 (H1N1) virus and treated with CEP (60, 30, 15 mg/kg/d) or oseltamivir (60 mg/kg/d). The changes in body weight, survival rates, viral titers, proinflammatory cytokine levels and pathological parameters were detected. Results: CEP exhibited antiviral effects against multiple IAV strains, while also demonstrating anti-inflammatory effects in influenza virus-infected RAW264.7 and A549 cells. The results of the mechanism study indicated that CEP effectively suppressed IAV replication by limiting viral polymerase activity. On the other hand, CEP could modulate pro-inflammatory responses via inhibition of janus kinase/signal transducer and activator of transcription/ nuclear factor kappa B (JAK/STAT/NF‑κB) signaling pathways involved in influenza virus pathogenesis. Treatment of mice with CEP improved the survival rate and body weight of influenza virus-infected mice, reduced viral titers and alleviated influenza virus-induced pathological damage and inflammation in mouse lung tissue. Conclusion: Collectively, the anti-influenza virus property of CEP was a result of inhibiting viral polymerase activity and preventing virus-induced excessive inflammation, highlighting it might be an oral medication for the treatment of IAV infection

    Insight into the Taxonomic Resolution of <i>Apiospora</i>: Introducing Novel Species and Records from Bamboo in China and Thailand

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    Taxonomic studies of bambusicolous fungi in China and Thailand have resulted in the collection of three fascinating saprobic coelomycetes strains. Morphology coupled with combined gene analysis of ITS, LSU, TUB2, and TEF1-α DNA sequence data showed that they belong to the genus Apiospora, family Apiosporaceae. A new species from Thailand, Apiospora mukdahanensis, and new records of A. locuta-pollinis from China are herein described. In addition, based on both morphological data coupled with phylogenetics and nomenclatural analyses, A. mori is proposed as a new combination. Maximum likelihood, maximum parsimony and Bayesian analyses were performed to clarify the phylogenetic affinities of the species obtained in this study. Newly obtained strains are compared with morphologically- and phylogenetically-related taxa. The comprehensive descriptions, illustrations, and updated phylogeny are provided and discussed for intra-and intergeneric relationships within Apiospora species
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