Erratum to: Oxya chinensis sinuosa (OC) Extracts Protects ARPE-19 Cells against Oxidative Stress via Activation of the Mitogen-Activated Protein Kinases (MAPKs)/Nuclear Factor-κB (NF-κB) Pathway.

[This corrects the article DOI: 10.5851/kosfa.2024.e15.].

An Exploratory Study on the Conceptualization of Burnout among the Professional Esports Athletes: Focused on League of Legends Champions Korea League.

Research on the stress and burnout experienced by athletes in the esports field remains limited, necessitating an approach that considers the unique environment and circumstances of esports athletes. This study aims to explore the conceptualization of burnout experiences among professional esports athletes. The participants included 88 athletes from the League of Legends Championship Korea (LCK). Among these, in-depth interviews were conducted with 7 athletes who had experience in international tournaments (the World Championship), while an open-ended survey was completed by 81 athletes. Data collected through in-depth interviews and an open-ended survey were digitized and utilized for analysis. Through critical review by another author and inductive categorization, the conceptual components of esports athletes' burnout were derived. Through the analysis of 251 raw datum, it was conceptualized into five conceptual factors: performance, overtraining, interpersonal relationships, physical and psychological exhaustion, and career and motivation. The results of this study confirm that esports athletes, like athletes in other conventional sports, experience burnout during their careers, highlighting issues in their unique environment, particularly in aspects of interpersonal relationships and training and rest conditions. This research can serve as a foundational resource for effective athletes' psychological health management in the esports field and underscores the need for further research on burnout among esports athletes.

Oxya chinensis sinuosa (OC) Extracts Protects ARPE-19 Cells against Oxidative Stress via Activation of the Mitogen-Activated Protein Kinases (MAPKs)/ Nuclear Factor-κB (NF-κB) Pathway.

Oxya chinensis sinuosa (OC) is a well-known edible insect. Several researches on the health benefits of OC consumption have been performed to date; however, their effect on eye health remains largely unknown. This study aimed to assess the protective effects of OC extracts on the oxidative stress on the retinal pigment epithelium (RPE) cells. Oxidative damage has been identified as one of the key regulatory factors in age-related macular degeneration. H2O2-induced reactive oxygen species (ROS) production, a well-known oxidative stress factor, can cause cell death in retinal pigment epithelia cells. In this study, we found that three OC extracts effectively prevented H2O2-induced ROS production and subsequent death of ARPE-19 cells in a dose-dependent manner. In addition, the OC extracts inhibited the phosphorylation of mitogen-activated protein kinases including p38, JNK, and ERK. The OC extracts restored IκBα degradation induced by H2O2, indicating that OC extracts suppressed the activation of nuclear factor-κB. Furthermore, the three OC extracts were shown to have antioxidant effects by up-regulating the intracellular expression of key antioxidant proteins such as SOD, NQO, and HO-1. Here we demonstrated the antioxidant and anti-apoptotic effects of the OC extracts on ARPE-19, indicating their potential role in improving eye health. These results suggest that three OC extracts plays a critical role in oxidative stress-induced cell death protects in ARPE-19 cells.

The Longitudinal Mediating Effect of Smartphone Dependency on the Relationship between Exercise Time and Subjective Happiness in Adolescents.

The phenomenon of adolescents engaging in less physical activity as they age raises several concerns. Among these, we hypothesized that this trend may negatively impact their mental health and smartphone dependency. Thus, the aim of this study was to longitudinally examine the mediating effect of smartphone dependency in the relationship between adolescents' exercise time and subjective well-being. For analysis, publicly available data from the 2018 Korean Children and Youth Panel Survey were utilized, with a total of 2,242 participants' data included in the analysis. Latent growth modeling results revealed a significant linear decrease in adolescents' exercise time and subjective well-being each year, while smartphone dependency exhibited an increasing trend. Furthermore, the significance tests of indirect effects indicated that the mediating effect of the changing trend in smartphone dependency between the changing trends in exercise time and subjective happiness in adolescents was statistically significant. These findings suggest that as grade levels increase, reducing exercise time can lead to higher smartphone dependency among adolescents, ultimately resulting in decreased subjective well-being.

Protaetia brevitarsis seulensis larvae ethanol extract inhibits RANKL-stimulated osteoclastogenesis and ameliorates bone loss in ovariectomized mice.

Modulation of osteoclast formation could be a therapeutic target for inhibiting pathological bone destruction. The receptor activator of nuclear factor (NF)-κB ligand (RANKL) is known to be an essential factor in osteoclast differentiation and activation inducers. However, whether Protaetia brevitarsis seulensis (P. brevitarsis) larvae-a traditional animal-derived medicine used in many Asian countries-can inhibit RANKL-induced osteoclast formation and prevent ovariectomy (OVX)-induced bone loss has not been evaluated. Here, we aimed to investigate the anti-osteoporotic effects of P. brevitarsis larvae ethanol extract (PBE) in RANKL-stimulated RAW264.7 cells and OVX mice. In vitro, PBE (0.1, 0.5, 1, and 2 mg/mL) decreased RANKL­induced tartrate-resistant acid phosphatase (TRAP) activity and expression of osteoclastogenesis-associated genes and proteins. Furthermore, PBE (0.1, 0.5, 1, and 2 mg/mL) significantly inhibited the phosphorylation of p38 and NF-κB. Female C3H/HeN mice were divided into five groups (n = 5 per group), namely, sham-operated, OVX, OVX+PBEL (100 mg/kg, oral gavage), OVX+PBEH (200 mg/kg, oral gavage), and OVX+estradiol (0.03 µg/day, subcutaneous injection). High doses of PBE significantly increased femoral bone mineral density (BMD) and bone volume/tissue volume (BV/TV), whereas femoral bone surface/bone volume (BS/BV) and osteoclastogenesis-associated protein expression decreased compared to those in the OVX group. Moreover, PBE (200 mg/kg) significantly increased estradiol and procollagen type I N-terminal propeptide and decreased N-terminal telopeptide of type I collagen and C-terminal telopeptide of type I collagen compared to those in the OVX group. Our results suggest that PBE can be an effective therapeutic candidate for preventing or treating postmenopausal osteoporosis.

The Preparation and Physiochemical Characterization of Tenebrio molitor Chitin Using Alcalase.

Chitin is mostly produced from crustaceans, but it is difficult to supply raw materials due to marine pollution, and the commonly used chemical chitin extraction method is not environmentally friendly. Therefore, this study aims to establish a chitin extraction process using enzymes and to develop edible insect-derived chitin as an eco-friendly new material. The response surface methodology (RSM) was used to determine the optimal conditions for enzymatic hydrolysis. The optimal conditions for enzymatic hydrolysis by RSM were determined to be the substrate concentration (7.5%), enzyme concentration (80 µL/g), and reaction time (24 h). The solubility and DDA of the mealworm chitosan were 45% and 37%, respectively, and those of the commercial chitosan were 61% and 57%, respectively. In regard to the thermodynamic properties, the exothermic peak of mealworm chitin was similar to that of commercial chitin. In the FT-IR spectrum, a band was observed in mealworm chitin corresponding to the C=O of the NHCOCH3 group at 1645 cm-1, but this band showed low-intensity C=O in the mealworm chitosan due to deacetylation. Collectively, mealworm chitosan shows almost similar physical and chemical properties to commercial chitosan. Therefore, it is shown that an eco-friendly process can be introduced into chitosan production by using enzyme-extracted mealworms for chitin/chitosan production.

Lubricant skin on diverse biomaterials with complex shapes via polydopamine-mediated surface functionalization for biomedical applications.

Implantable biomedical devices require an anti-biofouling, mechanically robust, low friction surface for a prolonged lifespan and improved performance. However, there exist no methods that could provide uniform and effective coatings for medical devices with complex shapes and materials to prevent immune-related side effects and thrombosis when they encounter biological tissues. Here, we report a lubricant skin (L-skin), a coating method based on the application of thin layers of bio-adhesive and lubricant-swellable perfluoropolymer that impart anti-biofouling, frictionless, robust, and heat-mediated self-healing properties. We demonstrate biocompatible, mechanically robust, and sterilization-safe L-skin in applications of bioprinting, microfluidics, catheter, and long and narrow medical tubing. We envision that diverse applications of L-skin improve device longevity, as well as anti-biofouling attributes in biomedical devices with complex shapes and material compositions.

The Mediating Effect of Presenteeism on the Relationship between Emotional Labor and Work Engagement of Coaches for Disability Sports.

The aim of present study was to examine the mediating effect of presenteeism on the relationship between emotional labor and work engagement of coaches for disability sports. A total of 198 coaches in Korea participated in this study. Participants responded a survey measuring emotional labor, presenteeism, and work engagement. After analyzing the correlation between each variable, the mediation model was verified through structural equation model analysis. The results reveal that emotional labor of coaches for disability sports positively predicted their work engagement, but negatively predicted presenteeism. In addition, the participants' presenteeism can have a negative effect on their work engagement. Moreover, completing work in presenteeism was found to mediate the relationship between the deep acting and surface acting in emotional labor and work engagement of disability sports coaches.

Entropymetry for detecting microcracks in high-nickel layered oxide cathodes.

Electric vehicles (EVs) are imposing ever-challenging standards on the lifetime and safety of lithium-ion batteries (LIBs); consequently, real-time nondestructive monitoring of battery cell degradation is highly desired. Unfortunately, high-nickel (Ni) layered oxides, the preferred LIB cathodes for EVs, undergo performance degradation originating from microcrack formation during cycling. Entropymetry is introduced as a real-time analytic tool for monitoring the evolution of microcracks in these cathodes along the state of charge. The entropy change of the layered cathode is associated with the lattice configuration and reflects the structural heterogeneity relevant to the evolution of these microcracks. The structural heterogeneity was correlated with peak broadening in in-situ X-ray diffractometry while varying the experimental conditions that affect crack formation such as the upper cutoff voltage during charging and the Ni-content of the active material. Entropymetry, proposed here as a nondestructive diagnostic tool, can contribute greatly to the safe and reliable operation of LIBs for EVs.

The Effect of Autonomy and Self-Control on Changes in Healthy Lifestyles of Inactive College Students through Regular Exercise.

This study aimed to verify the influence of autonomy and self-control as psychological factors on the changes in lifestyles of inactive college students by participating in regular exercise. A total of 188 university students in Seoul, Korea, taking physical fitness classes for 5 weeks held three times a week participated in the surveys. Surveys were conducted in the first session (T1) and 15th session (T2) of the classes. Autonomy in exercise participation and self-control were measured at T1, and healthy lifestyle was measured at both T1 and T2. A paired t-test was used to measure the changes in healthy lifestyle between two time points, and hierarchical regression analysis was conducted to determine the effect of autonomy in exercise participation and self-control measured at T1 on the healthy lifestyle score at T2. According to the analysis, participants' healthy lifestyles were improved with a statistically significant difference between pre- and post-exercise. Furthermore, the levels of autonomy and self-control before the fitness classes positively influenced the participants' healthy lifestyle after the classes even when the influence of healthy lifestyle measured before the classes was controlled. Thus, it was confirmed that autonomy for participation and self-control are important to change one's healthy lifestyle through regular exercise participation.

Mealworm Ethanol Extract Enhances Myogenic Differentiation and Alleviates Dexamethasone-Induced Muscle Atrophy in C2C12 Cells.

Aging, and other disease-related muscle disorders are serious health problems. Dexamethasone (DEX), a synthetic glucocorticoid, can trigger skeletal muscle atrophy. This study examined the effects of mealworm (Tenebrio molitor larva) ethanol extract (TME) on C2C12 myoblast differentiation and DEX-induced myotube atrophy. TME induced myotube formation compared to the differentiation medium (DM) group. TME also significantly increased the mRNA expression of muscle creatine kinase (CKm) and myogenic regulatory factors (MRFs), such as myogenin (MyoG), myogenic factor (Myf)5, and MRF4 (Myf6). TME dramatically increased the muscle-specific protein, MyoG, compared to the control, whereas the expression of myogenic differentiation 1 (MyoD) remained unchanged. It also activated the mammalian target of rapamycin (mTOR) signaling pathway. In the DEX-induced muscle atrophy C2C12 model, TME reduced the gene expression of atrogin-1, muscle RING finger protein-1 (MuRF-1), and myostatin, which are involved in protein degradation in skeletal muscles. Furthermore, TME elevated the phosphorylation of forkhead box O3 (FoxO3α) and protein kinase B (Akt). These findings suggest that TME can enhance myotube hypertrophy by regulating the mTOR signaling pathway, and can rescue DEX-induced muscle atrophy by alleviating atrophic muscle markers mediated by Akt activation. Thus, TME can be a potential therapeutic agent for treating muscle weakness and atrophy.

Predicting Deviant Behaviors in Sports Using the Extended Theory of Planned Behavior.

The purpose of the present study is to examine the deviant behaviors of young athletes the using extended theory of planned behavior (TPB) and impulsivity. About 536 middle and high school athletes in South Korea answered a set of questionnaires that measured their attitude, subjective norms, perceived behavioral control, intention, ethical obligation, and impulsivity. Structural equation model (SEM) analysis revealed that the extended TPB model is adequate to explain deviant behaviors in sports. Further, the underlying intentions that motivate the deviant behaviors of athletes in sports were significantly predicted by perceived behavioral control and moral obligation. Findings also suggested that the intention for deviant behaviors in sports more readily manifests as an actual act when the impulsivity scores are high. Theoretical contributions and practical implications are addressed in the Discussion section.

Anticancer Activity of Periplanetasin-5, an Antimicrobial Peptide from the Cockroach Periplaneta americana.

Cockroaches live in places where various pathogens exist and thus are more likely to use antimicrobial compounds to defend against pathogen intrusions. We previously performed an in silico analysis of the Periplaneta americana transcriptome and detected periplanetasin-5 using an in silico antimicrobial peptide prediction method. In this study, we investigated whether periplanetasin-5 has anticancer activity against the human leukemia cell line K562. Cell growth and survival of K562 cells treated with periplanetasin-5 were decreased in a dose-dependent manner. By using flow cytometric analysis, acridine orange/ethidium bromide (AO/EB) staining and DNA fragmentation, we found that periplanetasin-5 induced apoptotic and necrotic cell death in leukemia cells. In addition, these events were associated with increased levels of the pro-apoptotic proteins Fas and cytochrome c and reduced levels of the anti-apoptotic protein Bcl-2. Periplanetasin-5 induces the cleavage of pro-caspase-9, pro-caspase-8, pro-caspase-3, and poly (ADP-ribose) polymerase (PARP). The above data suggest that periplanetasin-5 induces apoptosis via both the intrinsic and extrinsic pathways. Moreover, caspase-related apoptosis was further confirmed by using the caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (Z-VAD-FMK), which reversed the periplanetasin-5-induced reduction in cell viability. In conclusion, periplanetasin-5 caused apoptosis in leukemia cells, suggesting its potential utility as an anticancer therapeutic agent.

Motivation and Intention Toward Physical Activity During the COVID-19 Pandemic: Perspectives From Integrated Model of Self-Determination and Planned Behavior Theories.

Background: In attempts to hinder the spread of the Coronavirus disease 2019 (COVID-19), many countries have continued distancing, isolation, and quarantine measures, which has led to limited opportunity of physical activity. This study provides empirical support for a motivational process behind physical activity during the COVID-19 pandemic by testing the influence of psychosocial variables derived from the integrated model of self-determination theory (SDT) and the theory of planned behavior (TPB). Methods: A cross-sectional survey was conducted among Korean adults (N = 248). Participants completed the measures of SDT and TPB constructs modified to reflect their participation in physical activity during the COVID-19 pandemic. A sample size of 243 participants was employed, and the integrated model was tested using serial multiple mediation analysis to check the hypothesized relationships. Results: Findings indicated that in the COVID-19 context, the satisfaction of basic psychological needs positively predicts the level of self-determined motivations for physical activity, which is partially related to the level of social cognitive beliefs and intentions. The findings also demonstrated that attitude toward physical activity during COVID-19 was a major variable explaining the serial multiple relationships between the SDT and TPB constructs. The potential influence of demographics (gender, age, marital status, and past physical activity) was controlled as a covariate, and no significant effects were identified. Conclusion: The current study identified the psychosocial mechanisms of intention of South Koreans' physical activity during the COVID-19 pandemic, which could be used as an empirical basis for the development of interventions to maintain or strengthen physical activity in unprecedented situations.

The Effect of Changes in Physical Self-Concept through Participation in Exercise on Changes in Self-Esteem and Mental Well-Being.

The aim of the present study was to examine the impact of the changes in physical self-concept induced by exercise participation on the changes in global self-esteem and mental well-being using a structural model analysis. A total of 189 university students in Seoul, Korea, participated in the present study for two waves. The participants responded through a survey measuring physical self-concept, self-esteem, and mental well-being before and after a six-week exercise course. Regression analysis was used to calculate the amount of change in each variable, and the calculated residual scores were used for correlation analysis and structural model analysis. The amounts of changes in the variables are significantly correlated with each other and there was a complementary mediating effect of the changes in self-esteem on the pathway from the changes in physical self-concept to the changes in mental well-being. Physical self-concept changed by exercise participation might directly and positively influence mental well-being, and it can indirectly influence the changes in mental well-being via the improvement of self-esteem.

Antiseptic effect of antimicrobial peptide psacotheasin 2 derived from the yellow-spotted longicorn beetle (Psacothea hilaris).

Given the challenges posed by antibiotic resistant microbes and the high mortality rate associated with sepsis, there is an urgent need to develop novel peptide antibiotics that exhibit both antimicrobial and anti-inflammatory activities. Herein, we evaluated antimicrobial activity and anti-inflammatory activity of psacotheasin 2, one of the antimicrobial peptide candidates identified previously using an in silico analysis on the transcriptome of Psacothea hilaris. In addition to exhibiting antimicrobial activities against microorganisms without inducing hemolysis, psacotheasin 2 also decreased the nitric oxide production in lipopolysaccharide (LPS)-induced Raw264.7 cells. Moreover, ELISA and western blot analysis revealed that psacotheasin 2 reduced the expression levels of pro-inflammatory enzymes such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Further, we found that psacotheasin 2 markedly reduced the expression levels of pro-inflammatory cytokines (IL-6 and IL-1ß) by regulating mitogen-activated protein kinases (MAPKs) and nuclear factor-kB (NF-kB) signaling in LPS-induced Raw264.7 cells. We also confirmed that the binding of psacotheasin 2 to bacterial cell membranes occurs via a specific interaction with LPS. In mouse models of LPS-induced shock, psacotheasin 2 significantly enhanced the survival rate and recovered weight by attenuating pro-inflammatory cytokines. Thus, psacotheasin 2 could be a promising candidate as a peptide antiseptic agent.

Estimation of the Continuous Walking Angle of Knee and Ankle (Talocrural Joint, Subtalar Joint) of a Lower-Limb Exoskeleton Robot Using a Neural Network.

A lower-limb exoskeleton robot identifies the wearer's walking intention and assists the walking movement through mechanical force; thus, it is important to be able to identify the wearer's movement in real-time. Measurement of the angle of the knee and ankle can be difficult in the case of patients who cannot move the lower-limb joint properly. Therefore, in this study, the knee angle as well as the angles of the talocrural and subtalar joints of the ankle were estimated during walking by applying the neural network to two inertial measurement unit (IMU) sensors attached to the thigh and shank. First, for angle estimation, the gyroscope and accelerometer data of the IMU sensor were obtained while walking at a treadmill speed of 1 to 2.5 km/h while wearing an exoskeleton robot. The weights according to each walking speed were calculated using a neural network algorithm programmed in MATLAB software. Second, an appropriate weight was selected according to the walking speed through the IMU data, and the knee angle and the angles of the talocrural and subtalar joints of the ankle were estimated in real-time during walking through a feedforward neural network using the IMU data received in real-time. We confirmed that the angle estimation error was accurately estimated as 1.69° ± 1.43 (mean absolute error (MAE) ± standard deviation (SD)) for the knee joint, 1.29° ± 1.01 for the talocrural joint, and 0.82° ± 0.69 for the subtalar joint. Therefore, the proposed algorithm has potential for gait rehabilitation as it addresses the difficulty of estimating angles of lower extremity patients using torque and EMG sensors.

Anterior Cable Reconstruction Using the Biceps Tendon in Retracted Anterior L-Shaped Rotator Cuff Tears.

Repair of a retracted anterior L-shaped rotator cuff tear is challenging because of the lack of mobilization of the torn tendon and destruction of the rotator cable. Restoring the anterior rotator cable decreases gap formation of the repaired tendon, leading to maintenance of the repair integrity of the anterior supraspinatus tendon. This Technical Note introduces the surgical technique of anterior cable reconstruction using the proximal biceps tendon for a retracted anterior L-shaped rotator cuff tear.

De novo assembly and functional annotation of the Red-striped golden stink bug (Poecilocoris lewisi) transcriptome.

Insect antimicrobial peptides (AMPs) have a wide range of functions and potential applications, and have recently attracted attention as alternative foods and medicines for humans. Our study performed transcriptome analysis to explore the potential of the red-striped golden stink bug (Poecilocoris lewisi), and as a result, we have discovered new features of P. lewisi that have not been identified. Specifically, defensin found in P. lewisi is a well-known AMP and is expressed by various plants, animals and fungi for host defense. Moreover, the discovery of defensin in P. lewisi provides new research and important information. In this study, we identified AMP and related DEG in P. lewisi that are closely related to human disease and immune response. These findings will provide the basis and important information for future research on P. lewisi that has not yet been studied.

Diagnosis and treatment of calcific tendinitis of the shoulder.

Calcific tendinitis is the leading cause of shoulder pain. Among patients with calcific tendinitis, 2.7%-20% are asymptomatic, and 35%-45% of patients whose calcific deposits are inadvertently discovered develop shoulder pain. If symptoms are present, complications such as decreased range of motion of the shoulder joint should be minimized while managing pain. Patients with acute calcific tendinitis respond well to conservative treatment and rarely require surgery. In contrast, patients with chronic calcific tendinitis often do not respond to conservative treatment and do require surgery. Clinical improvement takes time, even after surgical treatment. This review article summarizes the processes related to the diagnosis and treatment of calcific tendinitis with the aim of helping clinicians choose appropriate treatment options for their patients.