• Physical Therapy Rehabilitation Science
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• v.7 no.2
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• pp.72-77
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• 2018

Objective: This study aimed to compare the effects of core exercise methods on muscle activation and muscle thickness in healthy young adults and to propose effective core exercise methods. Design: Three-group pretest-posttest design. Methods: A total of 30 healthy young adults (14 males, 16 females) voluntarily participated in the study. Subjects were randomized to the prone plank exercise (n=10), reverse plank exercise (n=10), or bridge exercise (n=10) groups. Muscle activity and thickness of the rectus abdominis (RA), multifidus (MF), external oblique (EO), and internal oblique (IO) muscles were measured using surface electromyography and ultrasound. Subjects from each group participated in the exercises five times a week, with five 20-second sets during week 1. The set time was increased by 10 seconds per week. Results: Muscle activity and thickness in the prone plank, reverse plank, and bridge exercise group were statistically significant different for RA, MF, EO, and IO changes over time, and interaction between time and groups were also significantly different (p<0.05). We analyzed statistically significant differences between groups using a one-way analysis of variance for each period. A significant difference was observed after 4 weeks of exercise (p<0.05). Conclusions: The results suggest that the prone plank exercise is a beneficial method for enhancing muscle activation and thickness of the RA, EO, and IO compared to the reverse plank and bridge exercises. On the other hand, the reverse plank and bridge exercises are effective methods for enhancing the MF compared to the prone plank exercise.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.3
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• pp.29-37
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• 2019

PURPOSE: Prone hip extension (PHE) has been used for assessment of lumbo-pelvic movement and strengthening exercise for weakness of the hip joint muscles in patients with chronic low back pain (CLBP). On the other hand, few studies have examined which are the best PHE exercises to activate the gluteus maximus (GM) selectively in physical therapy practice. To aim of this study compared the muscle activity of the GM, rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA) during these four different prone hip extensions, PHE, PHE with quadriceps activation (PHEQA), PHE with ankle dorsiflexion (PHEAD), and PHE with ankle plantarflexion (PHEAP), in subjects with CLBP. METHODS: Nineteen subjects with low back pain participated in this study. Subject performed four PHE exercises and surface electromyography (EMG) was used to evaluate the muscle activity. Data were analyzed by one-way repeated-measures analysis of variance (${\alpha}=.05/3=.017$) and a Bonferroni adjustment was performed if a significant difference was found. RESULTS: The muscle activities recorded by EMG showed significant among the four exercises. The muscle activity of the GM increased significantly during PHEQA than during PHEAP (P=.012). CONCLUSION: PHEQA is the most effective exercise for eliciting greater GM muscle activation among the four PHE exercises in subjects with CLBP.

• Natural Product Sciences
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• v.25 no.1
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• pp.28-33
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• 2019

A popular approach for the study of estrogen receptor ${\alpha}$ inhibition is to investigate the protein-protein interaction between the estrogen receptor (ER) and the coactivator surface. In our study, we investigated phytochemicals from Rubus coreanus that were able to disrupt $ER{\alpha}$ and coactivator interaction with an $ER{\alpha}$ antagonist. The E-screen assay and molecular docking analysis were performed to evaluate the effects of the estrogenic activity of R. coreanus extract and its constituents on the MCF-7 human breast cancer cell line. At $100{\mu}g/mL$, R. coreanus extract significantly stimulated cell proliferation ($574.57{\pm}8.56%$). Sanguiin H6, which was isolated from R. coreanus, demonstrated the strongest affinity for the $ER{\alpha}$ coactivator-binding site in molecular docking analysis, with a binding energy of -250.149. The initial results of the study indicated that sanguiin H6 contributed to the estrogenic activity of R. coreanus through the activation of the $ER{\alpha}$ coactivator-binding site.

• The Korean journal of sports medicine
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• v.36 no.4
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• pp.197-206
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• 2018

Purpose: This study analyzed the muscle activity changes induced by motions of reaching forward and chest expansion that were examined from the bilateral muscles with rectus abdominis, external oblique, multifidus, and longissimus thoracic using Pilates cadillac instrument. Methods: Nine young adult women, who have no musculoskeletal disorder and any of chronic diseases, were participated. Surface electromyography system was used for recording of all signals produced by muscles, and then normalized as percentage of maximum voluntary isometric contraction (%MVIC). The paired t-test and repeated measures of analysis of variance was performed. Results: Reaching-forward motion showed a higher muscle activity from non-dominant external oblique muscle than that of the chest-expansion motion. During both reaching-forward motion and chest-expansion motion, MVIC values collected from dominant side of external oblique muscle were shown a significantly lower than the values obtained from non-dominant side (p<0.05). Conversely, %MVIC values in external oblique muscle collected from dominant side showed a significantly higher than the values obtained from non-dominant side of the same oblique muscle (p<0.05). Reaching-forward motion was caused a higher %MVIC on non-dominant external oblique muscle than that of the chest-expansion motion (p<0.05). Regardless of dominant or non-dominant sides, external oblique muscle was shown the highest activation rate of all the other muscles during reaching forward action, and longissimus thoracic muscle was shown the highest activation rate of all the other muscles during chest expansion action. Conclusion: Reaching-forward motion is suitable for activating an external oblique muscle, and chest-expansion motion is an effective enough in activating of longissimus thoracic muscle.

• Physical Therapy Rehabilitation Science
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• v.11 no.2
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• pp.245-252
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• 2022

Objective: This study aimed to investigate the abdominal muscle activity difference while performing the abdominal bracing technique focusing on inspiration (abdominal bracing group), the general abdominal bracing technique (general bracing group), and the abdominal hollowing technique (abdominal hallowing group) Design: A cross-sectional study design. Methods: Thirty-three healthy participants were recruited for this study. The participants were allocated to 3 different groups; Abdominal bracing group, general bracing group, and abdominal hallowing group. The surface electromyography was placed over the rectus abdominis, external oblique, and internal oblique muscles to collect the activation of abdominal muscles during the trial. Results: The muscle activity of the abdominal bracing group and general bracing groups was significantly higher in all abdominal muscles than in the abdominal hollowing group (p<0.05) Both rectus abdominis and external oblique muscles showed higher muscle activations in the abdominal bracing group over the general bracing group (p<0.05). However, the ratio of bilateral external obliques and rectus abdominis to bilateral internal obliques was highest when the hollowing technique was applied (p<0.05). Conclusions: The results of study showed the abdominal bracing technique that emphasized inhalation rather than the abdominal hollowing technique or general abdominal bracing technique increased the activity of the abdominal muscles. Therefore, this study is considered to be a data for effective training if the abdominal bracing technique that emphasizes inhalation is applied as a method to increase the activation of the abdominal muscles.

• Journal of Ginseng Research
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• v.46 no.5
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• pp.700-709
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• 2022

Background: Ginsenoside Rd is a natural compound with promising neuroprotective effects. However, the underlying mechanisms are still not well-understood. In this study, we explored whether ginsenoside Rd exerts protective effects on cerebral endothelial cells after oxygen-glucose deprivation/reoxygenation (OGD/R) treatment and its potential docking proteins related to the underlying regulations. Method: Commercially available primary human brain microvessel endothelial cells (HBMECs) were used for in vitro OGD/R studies. Cell viability, pyroptosis-associated protein expression and tight junction protein degradation were evaluated. Molecular docking proteins were predicted. Subsequent surface plasmon resonance (SPR) technology was utilized for validation. Flow cytometry was performed to quantify caspase-1 positive and PI positive (caspase-1+/PI+) pyroptotic cells. Results: Ginsenoside Rd treatment attenuated OGD/R-induced damage of blood-brain barrier (BBB) integrity in vitro. It suppressed NLRP3 inflammasome activation (increased expression of NLRP3, cleaved caspase-1, IL-1β and GSDMD-N terminal (NT)) and subsequent cellular pyroptosis (caspase-1+/PI + cells). Ginsenoside Rd interacted with SLC5A1 with a high affinity and reduced OGD/R-induced sodium influx and potassium efflux in HBMECs. Inhibiting SLC5A1 using phlorizin suppressed OGD/R-activated NLRP3 inflammasome and pyroptosis in HBMECs. Conclusion: Ginsenoside Rd protects HBMECs from OGD/R-induced injury partially via binding to SLC5A1, reducing OGD/R-induced sodium influx and potassium efflux, thereby alleviating NLRP3 inflammasome activation and pyroptosis.

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.2
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• pp.136-143
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• 2022

Recent progress has been made to establish intestinal organoids for an in vitro model as a potential alternative to an in vivo system in animals. We previously reported a reliable method for the isolation of intestinal crypts from the small intestine and robust three-dimensional (3D) expansion of intestinal organoids (basal-out) in adult bovines. The present study aimed to establish next-generation intestinal organoids for practical applications in disease modeling-based host-pathogen interactions and feed efficiency measurements. In this study, we developed a rapid and convenient method for the efficient generation of intestinal organoids through the modulation of the Wnt signaling pathway and continuous apical-out intestinal organoids. Remarkably, the intestinal epithelium only takes 3-4 days to undergo CHIR (1 µM) treatment as a Wnt activator, which is much shorter than that required for spontaneous differentiation (7 days). Subsequently, we successfully established an apical-out bovine intestinal organoid culture system through suspension culture without Matrigel matrix, indicating an apical-out membrane on the surface. Collectively, these results demonstrate the efficient generation and next-generation of bovine intestinal organoids and will facilitate their potential use for various purposes, such as disease modeling, in the field of animal biotechnology.

• Journal of the Korean Institute of Gas
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• v.26 no.5
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• pp.16-21
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• 2022

The reaction rate of a catalyst for producing hydrogen using the methanol steam reforming reaction was studied. It was prepared by impregnating copper, which is often used in methanol synthesis, as the main active metal, using hydrotalcite, which has excellent porosity and thermal stability, high specific surface area, weak Lewis acid point, and basicity, as a support. Activation energy and Pre-exponential factors were identified. In this study, the activation energy of the hydrotalcite catalyst impregnated with 20 wt% copper was calculated to be 97.4 kJ/mol and the Pre-exponential was 5.904 × 10¹⁰. Process simulation was performed using the calculated values and showed a similar tendency to the experimental results.

• Clean Technology
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• v.16 no.1
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• pp.12-18
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• 2010

The object of the present study is to apply KF/MgO catalysts to remove sulfur dioxide from dibenzothiophene sulfone, a by-product of oxidative desulfurization. Potassium fluoride was deposited via an impregnation method on MgO. The effects KF loading and calcination on the characteristics of the KF/MgO catalysts were investigated through the BET surface area, XRF, XRD, and temperature-programmed desorption of $CO_2$. The catalytic performances of the samples were investigated during the decomposition of dibenzothiophene sulfone to biphenyl and sulfur dioxide gas. KF loaded on MgO prepared by the impregnation method showed high catalytic activities for the decomposition of dibenzothiophene sulfone. The higher activity of KF/MgO just dried at 373 K, avoiding the usual activation at high temperature, than that over the calcined catalyst is ascribed to increase of the amount of basic sites. The high basicity probably may be due to the coordinately unsaturated $F^-$. The simply dried 10 % KF/MgO catalyst, without the usual activation at high temperature, showed the optimal catalytic properties.

• Physical Therapy Korea
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• v.30 no.3
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• pp.221-229
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• 2023

Background: In modern society, the use of computers accounts for a large proportion of our daily lives. Although substantial research is being actively conducted on musculoskeletal diseases resulting from computer use, there has been a recent surge in interest in improving the working environment for prevention. Objects: This study aimed to examine the effects of posture correction feedback (PCF) on changes in neck posture and muscle activation during computer typing. Methods: The participants performed a computer typing task in two sessions, each lasting 16 minutes. The participant's dominant side was photographed and analyzed using ImageJ software to verify neck posture. Surface electromyography (EMG) was used to confirm the participant's cervical erector spinae (CES) and upper trapezius muscle activities. The EMG signal was analyzed using the percentage of reference voluntary contraction and amplitude probability distribution function (APDF). In the second session, visual and auditory feedback for posture correction was provided if the neck was flexed by more than 15° in the initial position during computer typing. A 20-minute rest period was provided between the two sessions. Results: The neck angle (p = 0.014), CES muscle activity (p = 0.008), and APDF (p = 0.015) showed significant differences depending on the presence of the PCF. Furthermore, significant differences were observed regarding the CES muscle activity (p = 0.001) and APDF (p = 0.002) over time. Conclusion: Our study showed that the feedback system can correct poor posture and reduces unnecessary muscle activation during computer work. The improved neck posture and reduced CES muscle activity observed in this study suggest that neck pain can be prevented. Based on these results, we suggest that the PCF system can be used to prevent neck pain.