• Journal of the Ergonomics Society of Korea
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• v.22 no.1
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• pp.1-15
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• 2003

The resonance behaviour needs be understood to identify the mechanisms responsible for the dynamic characteristics of human body, to allow for the non-linearity when predicting the influence of seating dynamics, and to predict the adverse effects caused by various magnitudes of vibration. However, there are currently no known studies on the effect of vibration magnitude on the transmissibility to thoracic or lumbar spine of the seated person, despite low back pain(LBP) being the most common ailment associated with whole-body vibration. The objective of this paper is to develop a proper mathematical human model for LBP and musculoskeletal injury of the crew in a maritime vehicle. In this study, 7 degree-of-freedom including 2 non-rigid mass representing wobbling visceral and intestine mass, is proposed. Also, when compared with previously published experimental results, the model response was found to be well-matching. When exposed to various of vertical vibration, the human model shows appreciable non-linearity in its biodynamic responses. The relationships of resonance for LBP and musculoskeletal injury during whole-body vibration are also explained.

• International Journal of Highway Engineering
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• v.17 no.3
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• pp.117-124
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• 2015

PURPOSES : The purpose of this study is to verify traffic accident injury severity factors for elderly drivers and the relative relationship of these factors. METHODS : To verify the complicated relationship among traffic accident injury severity factors, this study employed a structural equation model (SEM). To develop the SEM structure, only the severity of human injuries was considered; moreover, the observed variables were selected through confirmatory factor analysis (CFA). The number of fatalities, serious injuries, moderate injuries, and minor injuries were selected for observed variables of severity. For latent variables, the accident situation, environment, and vehicle and driver factors were respectively defined. Seven observed variables were selected among the latent variables. RESULTS : This study showed that the vehicle and driver factor was the most influential factor for accident severity among the latent factors. For the observed variable, the type of vehicle, type of accident, and status of day or night for each latent variable were the most relative observed variables for the accident severity factor. To verify the validity of the SEM, several model fitting methods, including ${\chi}^2/df$, GFI, AGFI, CFI, and others, were applied, and the model produced meaningful results. CONCLUSIONS : Based on an analysis of results of traffic accident injury severity for elderly drivers, the vehicle and driver factor was the most influential one for injury severity. Therefore, education tailored to elderly drivers is needed to improve driving behavior of elderly driver.

• Natural Product Sciences
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• v.28 no.4
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• pp.194-200
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• 2022

Albizia julibrissin Durazz. (AJ; family Minosaceae) is widely distributed worldwide, and its stem bark has been used as a traditional herbal medicine. Acute kidney injury (AKI) is a clinical syndrome that results in sudden loss of renal function. This study aimed to investigate the effects of AJ against cisplatin-induced AKI using a human kidney proximal tubule epithelial cell line (HK-2) and cisplatin-treated mice. In vitro, cisplatin treatment increased apoptosis in HK-2 cells. However, AJ treatment decreased apoptosis of cisplatin-treated HK-2 cells. In vivo, cisplatin treatment accelerated renal injury by increasing the levels of renal injury markers, such as blood urea nitrogen, creatinine, kidney injury molecule 1, and neutrophil gelatinase-associated lipocalin, which were reversed by AJ treatment. Histopathologically, AJ treatment resulted in decreased renal damage with less tubular necrosis and brush border desquamation compared with the AKI group. Additionally, cisplatin treatment upregulated mitochondrial fission, a pathological characteristic of AKI, which was downregulated by AJ treatment. Along with increased mitochondrial fission, AJ treatment also reduced cisplatin-induced apoptosis. These results suggest that AJ may be a potential therapeutic agent for cisplatin-induced AKI.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.791-797
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• 2001

After brain injury, patients show a wide range in the degree of recovery. By a variety of mechanisms, the human brain is constantly undergoing plastic changes. Spontaneous recovery from brain injury in the chronic stage omes about because of plasticity. The brain regions are altered. resulting in functionally modified cortical network. This review cnsidered the neural plasticity from cellular and molecular mechanisms of synapse formation to behavioural recovery from brain injury in elderly humans. The stimuli required to elicit plasticity are thought to be activity-dependent elements. especially exercise and learning. Knowledge about the physiology of brain plasticity has led to the development of methods for rehabilitation.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.2
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• pp.135-143
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• 2018

Tumor necrosis $factor-{\alpha}$ ($TNF{\alpha}$) and the angiotensin system are involved in inflammatory diseases and may contribute to acute kidney injury. We investigated the mechanisms by which $TNF{\alpha}$-converting enzyme (TACE) contributes to lipopolysaccharide (LPS)-induced renal inflammation and the effect of TACE inhibitor treatment on LPS-induced cellular injury in human renal proximal tubule epithelial (HK-2) cells. Mice were treated with LPS (10 mg/kg, i.p.) and HK-2 cells were cultured with or without LPS ($10{\mu}g/ml$) in the presence or absence of a type 1 TACE inhibitor ($1{\mu}M$) or type 2 TACE inhibitor ($10{\mu}M$). LPS treatment induced increased serum creatinine, $TNF{\alpha}$, and urinary neutrophil gelatinase-associated lipocalin. Angiotensin II type 1 receptor, mitogen activated protein kinase (MAPK), and TACE increased, while angiotensin-converting enzyme-2 (ACE2) expression decreased in LPS-induced acute kidney injury and LPS-treated HK-2 cells. LPS induced reactive oxygen species and the down-regulation of ACE2, and these responses were prevented by TACE inhibitors in HK-2 cells. TACE inhibitors increased cell viability in LPS-treated HK-2 cells and attenuated oxidative stress and inflammatory cytokines. Our findings indicate that LPS activates renin angiotensin system components via the activation of TACE. Furthermore, inhibitors of TACE are potential therapeutic agents for kidney injury.

• Journal of the Ergonomics Society of Korea
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• v.22 no.1
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• pp.57-67
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• 2003

The resonance behaviour needs be understood to identify the mechanisms responsible for the dynamic characteristics of human body, to allow for the non-linearity when predicting the influence of seating dynamics. and to predict the adverse effects caused by various magnitudes of vibration. However, there are currently no known studies on the effect of vibration magnitude on the transmissibility to thoracic or lumbar spine of the seated person. despite low back pain(LBP) being the most common ailment associated with whole-body vibration. The objective of this paper is to develop a proper mathematical human model for LBP and musculoskeletal injury of the crew in a maritime vehicle. In this study, 7 degree-of-freedom including 2 non-rigid mass representing wobbling visceral and intestine mass, is proposed. Also. when compared with previously published experimental results, the model response was found to be well-matching. When exposed to various of vertical vibration, the human model shows appreciable non-linearity in its biodynamic responses. The relationships of resonance for LBP and musculoskeletal injury during whole-body vibration are also explained.

• YAKHAK HOEJI
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• v.59 no.5
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• pp.201-206
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• 2015

The aim of the present study was to optimize in vitro method for the prediction of drug-induced liver injury using human liver microsomes (HLM). Cytotoxicity test of cyclophosphamide and acetaminophen in HepG2 cells cultured with HLM showed that the newly established condition using 0.375 mg/ml HLM for 24 hr incubation was comparable or more sensitive than the previously established condition using 0.75 mg/ml HLM for 12 hr incubation. Although the cytotoxic effect of troglitazone was completely attenuated by 0.75 mg/ml HLM, it was augmented by 0.375 mg/ml HLM in the presence of the NADPH-generating system. The cytotoxic effect of chlormezanone, a withdrawn drug due to hepatotoxicity in human, was increased by HLM in the presence of the NADPH-generating system. In contrast, the cytotoxic effect of methapyrilene, a withdrawn drug due to hepatotoxicity in rats, was decreased by HLM in the presence of the NADPH-generating system. The present study suggests that the optimized in vitro method using HLM can be useful for the prediction of drug-induced hepatotoxicity.

• Archives of Plastic Surgery
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• v.35 no.1
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• pp.13-19
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• 2008

Purpose: Human adipose tissue-derived mesenchymal stem cells(hATSCs) can be differentiated into multiple mesenchymal lineages, including bone, cartilage, and muscle. And growth hormone play important roles in the normal growth and development of the CNS. In this study, we explored whether the transplanted hATSCs and growth hormones could improve functional recoveries from rats with contusive spinal cord injury. Methods: We divided 30 female rats, which were subjected to a weight driven implant spinal cord injury, into 3 groups with 10 rats each; Group A as a control group, group B with hATSCs transplantation on injured region, and group C with hATSCs transplantation and GH administration for 7 days. Then, we researched their neurologic functional recoveries before and 2, 4, and 8 weeks after transplantation using Basso-Beattie-Bresnahan (BBB) locomotor rating scale. And we checked Y-chromosome positive cells by FISH(Fluorescent in situ hybridization) to identify the survival of transplanted mesenchymal stem cells. Results: After 4 weeks of transplantation, the group B and group C showed significant improvement of neurologic function on BBB locomotor rating scale in comparison with the group A(Group A: $13.1{\pm}0.58$, Group B: $14.6{\pm}0.69$, Group C: $14.9{\pm}0.56$). Moreover, the group C displayed meaningful recovery of neurologic function after 8 weeks in comparison with group B (Group B: $15.7{\pm}0.63$, Group C: $16.5{\pm}1.14$). The group A, the control one, improved for 5 weeks after injury, and had no more recovery. On the other hand, Group B and C showed the improvement of neurologic function continuously for 9 weeks after injury. Conclusion: In this study, we found out that hATSCs transplantation have an effect on neurologic functional recovery of spinal cord injured rat and GH injection seems to bring the synergistic results on this good tendency.

• Nutrition Research and Practice
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• v.16 no.5
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• pp.589-603
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• 2022

BACKGROUND/OBJECTIVES: Previous studies have reported that protein supplementation contributes to the attenuation of inflammation. Serious trauma such as burn injury usually results in the excessive release of inflammatory factors and organs dysfunction. However, a few reports continued to focus on the function of protein ingestion in regulating burn-induced inflammation and organ dysfunction. MATERIALS/METHODS: This study established the rat model of 30% total body surface area burn injury, and evaluated the function of blended protein (mixture of whey and soybean proteins). Blood routine examination, inflammatory factors, blood biochemistry, and immunohistochemical assays were employed to analyze the samples from different treatment groups. RESULTS: Our results indicated a decrease in the numbers of white blood cells, monocytes, and neutrophils in the burn injury group administered with the blended protein nutritional support (Burn+BP), as compared to the burn injury group administered normal saline supplementation (Burn+S). Expressions of the pro-inflammatory factors (tumor necrosis factor-α and interleukin-6 [IL-6]) and chemokines (macrophage chemoattractant protein-1, regulated upon activation normal T cell expressed and secreted factor, and C-C motif chemokine 11) were dramatically decreased, whereas anti-inflammatory factors (IL-4, IL-10, and IL-13) were significantly increased in the Burn+BP group. Kidney function related markers blood urea nitrogen and serum creatinine, and the liver function related markers alanine transaminase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase were remarkably reduced, whereas albumin levels were elevated in the Burn+BP group as compared to levels obtained in the Burn+S group. Furthermore, inflammatory cells infiltration of the kidney and liver was also attenuated after burn injury administered with blended protein supplementation. CONCLUSIONS: In summary, nutritional support with blended proteins dramatically attenuates the burn-induced inflammatory reaction and protects organ functions. We believe this is a new insight into a potential therapeutic strategy for nutritional support of burn patients.

• Journal of Photoscience
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• v.9 no.2
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• pp.518-520
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• 2002

Photodynamic therapy (PDT) is a treatment modality based on photochemical reaction and the resultant cytotoxic reactive oxygen species. The platelet thrombus formation leading to stasis observed in vivo during PDT is called vascular shut down (VSD) effect. To investigate the mechanism of the VSD effect, we observed Human Umblical Vein Endothelial Cell (HUVEC) injury induced by photochemical reaction. We observed cell retraction and blebbing after PDT. It seems that the injury was not fetal and only morphological change. Then, the cytoplasm was stained by Calcein-AM and subendothelial area was evaluated from fluorescence microscopy. The rate of subendothelial area after PDT increased significantly. Second, we investigated interaction between neutrophils and HUVEC. Human promyelocytic leukemia cells (HL-60) were differentiated into neutrophil by incubation with all-trans retinoic acid. Calcein-AM labeled neutrophil adhesion to HUVEC was evaluated from fluorescence microscopy. PDT-induced neutrophil adhesion to HUVEC depended more on the exposure of subendothlial area than on neutrophil activation. This result suggests that there is a certain interaction between neutrophil and HUVEC during PDT.