• Journal of Life Science
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• v.30 no.7
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• pp.651-659
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• 2020

Cardiovascular disease is one of the leading causes of death across the world, and gold-standard treatments such as percutaneous coronary intervention and artery bypass grafting have various limitations including myocardial damage and subsequent maladaptive cardiac remodeling. To overcome this, stem-cell therapies are emerging as a promising strategy for cardiovascular regeneration. Endothelial progenitor cells (EPCs) have high potential to proliferate and differentiate into endothelial cells for vascularization and tissue regeneration, and several clinical trials have explored EPC function in tissue repair in relation to clinical safety and improving cardiac function. Consequently, EPC has been suggested as a feasible stem-cell therapy. However, autologous EPC transplantation in cardiovascular disease patients is restricted by risk factors such as age, smoking status, and hypertension that lead to reduced bioactivity in the EPCs. New approaches for improving EPC function and stem-cell efficacy have therefore been suggested, including cell priming, organoid culture systems, and enhancing transplantation efficiency through 3D bioprinting methods. In this review, we provide a comprehensive understanding of EPC characteristics, therapeutic approaches, and the current state of clinical research into EPCs as stem-cell therapy for cardiovascular disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.677-683
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• 2008

The antioxidant activities of Wisteria floribunda flowers (WFF) were evaluated. The samples were prepared by extracting separately two different colored flowers (purple and white) with four different solvents (methanol, ethanol, acetone, and water). The antioxidant properties were evaluated by determining total phenolic contents (TPC), radical scavenging activity (RSA), and reducing power (RP). Water extract from purple WFF and ethanol extract of white WFF showed the highest total phenol contents (491 and 787 ${\mu}M$ gallic acid equivalents), respectively. Water extracts of purple and white WFF also showed higher RSA. In the case of RP, ethanol extract of purple WFF, methanol and water extracts of white WFF showed relatively higher values. The 200 ${\mu}M$ $H_2O_2$ induced oxidative DNA damage in human leukocytes was significantly inhibited with WFF extracts excluding ethanol and acetone extracts of purple flowers. These results suggest that W. floribunda flowers have significant antioxidative activity and protective effect against oxidative DNA damage.

• Journal of Science and Technology Studies
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• v.2 no.2 s.4
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• pp.145-189
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• 2002

This paper explores into the potential contribution of welfare science and technology(WST) to meeting the challenges of ageing. Drawing on the literature about gerontechnology, this paper considers the application of scientific knowledge for welfare of an aging population. WST for the improvement of the daily functioning of the elderly people can not only prevent, delay or compensate for the declines or impairments of coginitive and physical functions (by assistive technology) but also enhance personal ability to overcome problems either by supporting the person's abilities (by supportive technology) or by changing the environment (by public welfare technology). This paper draws attention to a paradigm change in the conceptualization of disability and its ramifications for the role of technology and aging. A range of approaches such as Barrier-Free design, Universal Design points to new directions of WST in which products and services are devised to improve the quality of life for all people, and hence enhancing the socio-economic vitality. It is suggested that the future of welfare science and technology will be based in large measure on its goal to reduce or prevent individual and structural lag in the relationships between people and their environments. Addressing issues of the broader physical and social environment will emphasize the goal of prevention and the view that environmental needs for aging population are changing over time.

• Journal of Life Science
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• v.31 no.4
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• pp.400-409
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• 2021

Sanguinarine, a natural benzophenanthridine alkaloid, has been considered a potential therapeutic target for the treatment of cancer because it can induce apoptosis in human cancer cells; however, the underlying mechanisms of action still remain unclear. Tumor suppressor p53 deletion or mutation is an important reason for the resistance of colorectal cancer cells to anticancer agents. Therefore, in the present study, the role of p53 during apoptosis induced by sanguinarine was investigated in p53wild type (WT, p53+/+) and p53null (p53+/+) HCT116 colon carcinoma cells. Sanguinarine significantly caused greater reductions in cell viability in HCT116 (p53+/+) cells than in HCT116 (p53-/-) cells. Consistently, sanguinarine promoted more DNA damage and apoptosis in HCT116 (p53+/+) cells than in HCT116 (p53-/-) cells while increasing the expression of p53 and cyclin-dependent kinase inhibitor p21^WAF1/CIP1. Sanguinarine increased the activity of caspase-8 and caspase-9, which are involved in the initiation of extrinsic and intrinsic apoptosis pathways, respectively, and it activated caspase-3, a typical effect caspase, in HCT116 (p53+/+) cells. Sanguinarine also increased the generation of reactive oxygen species (ROS), and the Bax/Bcl-2 ratio, while destroying the integrity of mitochondria in HCT116 (p53+/+) cells, but not in HCT116 (p53-/-) cells. Overall, the results indicate that sanguinarine induced p53-dependent apoptosis through ROS-mediated activation of extrinsic and intrinsic apoptotic pathways in HCT116 colorectal cancer cells.

• Journal of Life Science
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• v.29 no.10
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• pp.1071-1079
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• 2019

In this study, we investigated the antioxidant and anti-aging activities of Schisandra chinensis seed fractions by adding them to UVB-irradiated HaCaT cells and analyzing the suppression of matrix metalloproteinases (MMPs). An electron-donating assay, ABTS radical scavenging assay, and hydrogen peroxide scavenging assay showed that the ethyl acetate fraction of S. chinensis seed (SCEAf) has scavenging activities. A collagenase inhibition activity assay showed that SCEAf had inhibitory effects of over 92.3% at $500{\mu}g/ml$ concentration. An MTT assay was performed to determine the cytotoxicity of SCEAf in HaCaT cells and the results showed that SCEAf increased cellular viability in a concentration-dependent manner. In addition, SCEAf was found to increase the viability of cells irradiatged by UVB $50mJ/cm^2$. To examine the anti-aging effects of SCEAf on HaCaT cells irradiated with UVB $50mJ/cm^2$, the expression of MMP-1 and -3 was analyzed by Western blotting and reverse-transcription polymerase chain reaction. The results showed that MMP-1 and -3 proteins and mRNA levels were downregulated in a concentration-dependent manner in response to SCEAf. These results suggest that SCEAf can prevent aging and alleviate aging symptoms by inhibiting collagenase activity in skin keratinocytes damaged by UVB. Therefore, S. chinensis seeds may have the potential for use as functional ingredients with anti-aging effects in the cosmetic and food industries.

• Journal of Korean Foot and Ankle Society
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• v.19 no.4
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• pp.151-155
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• 2015

Purpose: The purpose of this study was to analyze the frequency and patterns of intra-articular lesions detected during ankle fracture surgery using ankle arthroscopy. Materials and Methods: Thirty patients (31 ankles) who underwent open reduction and internal fixation combined with ankle arthroscopy for acute ankle fracture at Inje University Busan Paik Hospital from June 2011 to September 2013 were evaluated. The ankle fractures were classified according to the AO/OTA (AO Foundation and Orthopaedic Trauma Association) classification and the intraarticular injuries were identified by ankle arthroscopy. Osteochondral lesions of the talus were divided into nine subtypes based on their locations, and the ligament injuries were classified according to avulsion fracture and rupture. Results: Using arthroscopy, abnormality in the distal tibiofibular ligament was found in 21 cases and osteochondral lesions and defects of the talus larger than 5 mm were detected in 26 cases. Among ligament injuries, anterior inferior tibio-fibular ligament injury was found in 14 cases, posterior inferior tibio-fibular ligament injury was found in two cases, deep deltoid ligament injury was found in three cases, and deep transverse tibio-fibular ligament injury was found in five cases. The locations of the osteochondral lesions were on the antero-lateral, antero-medial, centro-medial, centro-central, centro-lateral, and postero-lateral talus in 11, one, two, one, two, and nine cases, respectively. Conclusion: With early diagnosis and treatment arthroscopy performed at the time of intra-articular fracture surgery is expected to result in a good outcome.

• Journal of Korean Foot and Ankle Society
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• v.17 no.1
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• pp.34-39
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• 2013

Purpose: To evaluate the effectiveness of intraoperative stress test for diagnosis of occult Lisfranc injury. Materials and Methods: Between April 2009 and October 2012, 21 patients with occult Lisfranc injuries underwent intraoperative stress test and internal fixation. There were 11 males and 10 females with an average age of 45.3 years (range, 23~79 years). Injuries were caused by traffic accident in 10 cases, indirect force (twisting injury) in 8 cases, and crush in 2 cases, falling from a height in 1 case. Unstable injuries on stress radiograph in occult injury of Lisfranc joint were treated by open reduction or closed reduction and fixation with cannulated screw or K-wire. Radiological evaluation was assessed according to preoperative and postoperative diastasis between $1^{st}$ and $2^{nd}$ metatarsal base. Results: Assoicated injuries were 9 cases of metatarsal fractures, 6 cases of cuneiform fractures and 6 cases of both metatarsal and cuneiform fractures. Medial and middle column fixation was in 13 cases, and three columns fixation was in 8 cases. Initial diastasis between $1^{st}$ and $2^{nd}$ metatarsal base was 2.8 mm (1.3~4.7 mm) on AP radiograph and postoperative diastasis between $1^{st}$ and $2^{nd}$ metatarsal base was 1.2 mm (0.5~2.4 mm) on AP radiograph. Conclusion: Even there is no sign of clear Lisfranc injury, it is necessary to pay attention and give evaluation on circumstances of occult Lisfranc injuries with metatarsal or cuneiform fractures. Intraoperative stress test is helpful to diagnose an occult Lisfranc injury. For unstable injuries on stress radiographs of occult Lisfranc joint injury, operative treatment with open or closed reduction and internal fixation is useful method.

• Journal of the Korean Institute of Gas
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• v.25 no.4
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• pp.1-9
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• 2021

The process and facilities of modern chemical plants are becoming increasingly complex, there is possibility of potential risk. Internal chemicals generate stress concentration when operated due to turbulence, laminar flow, pressure, temperature, friction, etc. It causes cumulative fatigue damage, which can damage or rupture chemical facilities and devices. The statistics of chemical accidents found that the highest rate of occurrence was in summer, and in the last five years statistics on chemical accidents, leakage incidents make up a decent percentage of accidents. Chemical leaks can cause serious human damage and economic damage, including explosions and environmental pollution. In this study, based on the leak accident of chemical plant, the risk analysis, and damage effects assessment were estimated using a 3D scanner and FLACS. As a result, if chemicals leak in summer, the risk is higher than in other seasons, the seasonal safety management measures, and countermeasure were estimated.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.1-8
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• 2020

This study presents a shear strength estimation model, in which the shear failure of a reinforced concrete (RC) member is assumed to be governed by the flexure-shear mechanism. Two shear demand curves and corresponding potential capacity curves for cracked tension and uncracked compression zones are derived, for which the bond mechanism developed between reinforcing bars and surrounding concrete is considered in flexural analysis. The shear crack concentration factor is also addressed to consider the so-called size effect induced in large RC members. In addition,unlike exising methods, a new formulation was addressed to consider the interaction between the shear contributions of concrete and stirrup. To verify the proposed method, an extensive shear database was established, and it appeared that the proposed method can capture the shear strengths of the collected test specimens regardless of their material properties, geometrical features, presence of stirrups, and bond characteristics.

• Composites Research
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• v.34 no.2
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• pp.101-107
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• 2021

Composite structures have components and joints. Theses connections or joints can be potentially weak points in the structure. The failure mode of the composite bolted joint is designed as a bearing failure mode for structural safety. The load-displacement relation exhibits bearing failure mode shows a nonlinear behavior after the initial failure and progressive failure behavior. In order to accurately predict the failure behavior of composite bolted joints, this study modified the shear damage variable calculation process in the existing progressive failure analysis model. The results of the bearing stress-bearing strain of the composite bolted joint were predicted using the modified progressive failure analysis model, and the modified model was verified through comparison with the previous progressive analysis model.