• 대한의생명과학회지
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• 제11권4호
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• pp.441-446
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• 2005

The molecular mechanism of ischemia/reperfusion injury remains unclear. Reactive oxygen species (ROS) are implicated in cell death caused by ischemia/reperfusion in vivo or hypoxia in vitro. Poly (ADP-ribose) polymerase (PARP) activation has been reported to be involved in hydrogen peroxide-induced cell death in renal epithelial cells. This study was therefore undertaken to evaluate the role of P ARP activation in chemical hypoxia in opossum kidney (OK) cells. Chemical hypoxia was induced by incubating cells with antimycin A, an inhibitor of mitochondrial electron transport. Exposure of OK cells to chemical hypoxia resulted in a time-dependent cell death. In OK cells subjected to chemical hypoxia, the generation of ROS was increased, and this increase was prevented by the $H_2O_2$ scavenger catalase. Chemical hypoxia increased P ARP activity and chemical hypoxia-induced cell death was prevented by the inhibitor of PARP activation 3-aminobenzamide. Catalase prevented OK cell death induced by chemical hypoxia. $H_2O_2$ caused PARP activation and $H_2O_2-induced$ cell death was prevented by 3-aminobenzamide. Taken together, these results indicate that chemical hypoxia-induced cell injury is mediated by PARP activation through H202 generation in renal epithelial cells.

• BMB Reports
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• 제43권12호
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• pp.789-794
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• 2010

A novel gene, designated mgt-6, containing four splicing variants, was isolated from a gene trap clone library of C3H/10T1/2 cells transfected with retroviral promoterless gene-trap vector, ROSAFARY. The transcript variants were differentially expressed in murine tissues and cell lines and differentially responded to diverse stimuli including TGF-${\beta}1$ and mitogen-activated protein kinase (MAPK) inhibitors. The mgt-6 gene encoded a protein of 37 or 11 amino acid residuals with cytoplasmic distribution. However, when C3H/10T1/2 cells were treated with 5-azacytidine, the protein translocated into cell nucleus as indicated by fused LacZ or C-terminally tagged EGFP. Our preliminary results suggest that further study on the role of mgt-6 gene in cell transformation and differentiation may be of significance.

• 한국가스학회지
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• 제17권4호
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• pp.39-44
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• 2013

최근 화학공장에서는 대형 폭발사고 등이 주로 유지 보수의 정비 시에 많이 발생되고 있다. 정비 시에 효과적인 재해예방을 하기 위해서는 핵심대상을 찾는 것이 매우 필요하다. 이 논문에서는 재해예방의 핵심요인을 찾기 위해 핵심대상으로 화학설비를 선정하였고, 화학설비별로 위험순위도를 정하여 재해예방의 대책을 세우는 우선순위를 밝히고자 하였다. 연구방법으로 화학설비의 종류는 재해분석을 통하여 찾고, 화학설비별 위험도는 재해분석을 통해 가능성인 재해빈도와 중대성인 재해강도의 근로손실일 수를 기준하여 산정하였다. 또한 화학설비별로 전문가들의 지식과 경험을 바탕으로 한 지식기반 기법에 의한 가능성과 중대성 자료를 활용하여 위험도를 산정하였다. 연구결과, 화학공장의 정비 시에 재해예방을 위해 화학설비별 위험순위는 반응기, 건조기, 탱크로리 등의 순위로 나타났다. 이 결과로부터 화학공장의 정비 시에 재해예방을 위해 위험순위에 따른 각별한 대책과 주의를 기울여야 할 것으로 사료된다.

• Journal of Oral Medicine and Pain
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• 제19권1호
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• pp.73-91
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• 1994

The author used rabbits in order to examine the effect of Ga-As low power generating semiconductor laser on artificially produced injuries of experimental animals. Artificially produced injuries include surgical wound of 3mm length, 2mm depth in size on ventral skin surface of rabbit and buccal mucosa, and electrical injury formed on opposite side of skin and buccal mucosa by electrical cauterization of same length and depth, and chemical injury formed by FC(Formocresol) solution applied on the anterior dorsal part of tongue. And then, on the experimental group, Ga-As laser was irradiated beginning on the day after the wound formation and continued to irradiate every each other day for five minutes. After1, 3, 6, 9, 13th day, certain number of animals of control and experimental group were sacrified, and wound site tissue was excised to make samples and was observed under light microscope. The following is the conclusions after comparing the healing procedure of experimental and control group. The following results were obtained : 1. Inflammation was decreased more rapidly in the experimental group than the control group. 2. In the surgical, the electrical and the chemical injuries in the oral mucosa, re-epithelialization was completed more rapidly in the experimental group than the control group. In the electrical injury on the skin, re-epithelialization was completed about 6 days after wound formation on both groups. 3. In the electrical and the surgical injuries on the oral mucosa, granulation tissue formation started at 3 days after injury on both groups, but in the chemical injury, it was completed about 3 days faster in the control group than the experimental group. In the surgical wound on the skin, it was completed about 9 days after injury, but faster in the experimental group. In the electrical injury on the skin, it was faster in the control group than the experimental group. 4. In the electrical and the surgical injuries on the oral mucosa, fibrosis was started at 6~9 days after injury on both groups, but regeneration of connective tissue in the experimental group was observed much more than the control group. 5. When comparing the effect of wound healing on skin and oral mucosa of control and experimental group, granulation tissue formation and re-epithelialization in the oral mucosa was more vigorous. In conclusion, the difference of timing and the sequence of wound healing process(inflammation, re-epithelialization, granulation tissue formation, fibrosis) following Laser irradiation between control and experimental group was not observed, but the healing tissue was observed much more in the Laser irradiated group.

• The Korean Journal of Physiology and Pharmacology
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• 제25권4호
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• pp.261-272
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• 2021

Doxorubicin (Dox) is widely used to the treatment of cancer, however, it could cause damage to gastric mucosa. To investigate the protective effects and related mechanisms of coenzyme Q10 (CoQ10) and vitamin C (VC) on Dox-induced gastric mucosal injury, we presented the survey of the 4 groups of the rats with different conditions. The results showed Dox treatment significantly induced GES-1 apoptosis, but preconditioning in GES-1 cells with VC or CoQ10 significantly inhibited the Dox-induced decrease and other harm effects, including the expression and of IκKβ, IκBα, NF-κB/p65 and tumor necrosis factor (TNF-α) in GES-1 cells. Moreover, high-throughput sequencing results showed Dox treatment increased the number of harmful gut microbes, and CoQ10 and VC treatment inhibited this effect. CoQ10 and VC treatment inhibits Dox-induced gastric mucosal injury by inhibiting the activation of the IkKB/IκBα/NF-κB/p65/TNF-α pathway, promoting anti-inflammatory effects of gastric tissue and regulating the composition of the intestinal flora.

• The Korean Journal of Physiology and Pharmacology
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• 제17권4호
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• pp.275-281
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• 2013

Astrocytes are reported to have critical functions in ischemic brain injury including protective effects against ischemia-induced neuronal dysfunction. Na-K ATPase maintains ionic gradients in astrocytes and is suggested as an indicator of ischemic injury in glial cells. Here, we examined the role of the Na-K ATPase in the pathologic process of ischemic injury of primary cultured astrocytes. Chemical ischemia was induced by sodium azide and glucose deprivation. Lactate dehydrogenase assays showed that the cytotoxic effect of chemical ischemia on astrocytes began to appear at 2 h of ischemia. The expression of Na-K ATPase ${\alpha}1$ subunit protein was increased at 2 h of chemical ischemia and was decreased at 6 h of ischemia, whereas the expression of ${\alpha}1$ subunit mRNA was not changed by chemical ischemia. Na-K ATPase activity was time-dependently decreased at 1, 3, and 6 h of chemical ischemia, whereas the enzyme activity was temporarily recovered to the control value at 2 h of chemical ischemia. Cytotoxicity at 2 h of chemical ischemia was significantly blocked by reoxygenation for 24 h following ischemia. Reoxygenation following chemical ischemia for 1 h significantly increased the activity of the Na-K ATPase, while reoxygenation following ischemia for 2 h slightly decreased the enzyme activity. These results suggest that the critical time for ischemia-induced cytotoxicity of astrocytes might be 2 h after the initiation of ischemic insult and that the increase in the expression and activity of the Na-K ATPase might play a protective role during ischemic injury of astrocytes.

• Journal of Korean Neurosurgical Society
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• 제65권2호
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• pp.196-203
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• 2022

Objective : To perform a comparative analysis of therapeutic effects associated with two different shapes of ceria nanoparticles, ceria nanorods (Ceria NRs) and ceria nanospheres (Ceria NSs), in an in vitro model of traumatic brain injury (TBI). Methods : In vitro TBI was induced using six-well confluent plates by manually scratching with a sterile pipette tip in a 6×6-square grid. The cells were then incubated and classified into cells with scratch injury without nanoparticles and cells with scratch injury, which were treated separately with 1.16 mM of Ceria NSs and Ceria NRs. Antioxidant activities and anti-inflammatory effects were analyzed. Results : Ceria NRs and Ceria NSs significantly reduced the level of reactive oxygen species compared with the control group of SH-SY5Y cells treated with Dulbecco's phosphate-buffered saline. The mRNA expression of superoxide dismutases was also reduced in nanoparticle-treated SH-SY5Y cells, but apparently the degree of mRNA expression decrease was not dependent on the nanoparticle shape. Exposure to ceria nanoparticles also decreased the cyclooxygenase-2 expression, especially prominent in Ceria NR-treated group than that in Ceria NS-treated group. Conclusion : Ceria nanoparticles exhibit antioxidant and anti-inflammatory effects in TBI models in vitro. Ceria NRs had better anti-inflammatory effect than Ceria NSs, but showed similar antioxidant activity.

• 대한안전경영과학회지
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• 제4권3호
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• pp.1-11
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• 2002

It has been Management for stabilize Enterprise-Management for Economic demand for to Productivity, Automation, customer satisfaction, Especially Semiconductor-Industry has been, potential-risk in working to factory to machine equipment, all kinds of utility, gas, chemical, electronic, Fire. This study of basic-purpose has Research Different From as Follow to analysis and Solution For semiconductor product Factory of a actual point Data and specific-gravity to Relation for company-Injury. 1. It has been try to Injury-Tendency and cause-Analysis for our County-Manufacture-Occupation. 2, Semiconductor Injury of Actual-condition in Enforcement for problem and Analysis that Injury Problem has occupated it Submitted to Solution for ordinary Injury theory View to point Solve at for New Model has applicated to that nilem for processed to Solution.

• 대한화학회지
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• 제38권1호
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• pp.74-79
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• 1994

Cu, Zn-SOD 억제제인 diethyldithiocarbamate(DDC)가 paraquat(PQ)에 의한 세포독성에 미치는 영향을 배양한 백서 섬유아세포에 DDC(30 mM)를 전처치하여 PQ를 100${\mu}M$이 되게 첨가해 배양하여 생존한 세포를 Carmichael 등의 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide(MTT)법에 의해 측정한 결과 DDC 전처치 대조군과 DDC 전처치 PQ 첨가군 사이에 유의한 세포생존율의 차이는 없었다. Catalase 억제제인 3-amino-1,2,4-triazol(AT)를 전처치하여 PQ를 100${\mu}$M을 첨가하고 배양한 섬유아세포의 생존율을 MTT법에 의해 측정한 결과 AT 전처치 PQ 첨가군에서 유의한 세포생존율의 감소를 나타냈다. 섬유아세포를 PQ(200${\mu}$M)로 처치한 후 Cu, Zn-SOD를 첨가하여 생존한 세포수를 각각 MTT법에 의해 측정한 결과 Cu, Zn-SOD 첨가로 인한 세포생존율의 유의한 변화는 없었다. PQ 처치군에 catalase 첨가로 PQ처리 대조군에 비하여 생존한 세포수가 유의하게 증가되었다. 이상의 실험결과 일차배양한 백서 섬유아세포를 AT로 전처리하면 PQ독성이 증가되고, catalase 첨가로 독성이 감소되며, DDC전처치나 Cu, Zn-SOD첨가로 PQ에 의한 세포생존에 미치는 영향이 적은 점으로 미루어, PQ 독성은 surperoxide보다 과산화수소농도와 더 밀접한 연관성이 있는 것으로 추정된다.

• Archives of Plastic Surgery
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• 제34권4호
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• pp.471-477
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• 2007

Purpose: Hydrofluoric acid(HF) is one of the most dangerous mineral acids with dissociated fluoride ions. As hydrofluoric acid is present in various household products(such as rust removers), a large population of industrials is at the risk of HF exposure. It is a very strong organic acid, used widely in glass etching, metal washing, and in the semiconductor industry. Even when using adequate safety measures, lack of care on the user's part results in chemical burn by HF. Symptoms caused by HF-induced chemical burns shows delayed manifestations resulting in a loss of proper treatment opportunities. We therefore reviewed 20 cases of HF-induced chemical burns and treatment principle. Methods: The objects of this study were 19 male patients and 1 female treated from March 2004 to March 2006. There were 19 cases of injury on digits and 1 on the wrist area. There were 15 cases of immediate treatment after sustaining HF-induced burns, and 5 cases of delayed treatment. As a principle, in the emergency treatment, partial or complete removal of the nail along with copious washing with normal saline was done, depending on the degree of HF invasion of the distal digital extremities. Results: The 15 cases who came to the hospital immediately after the injury were healed completely without sequelae, and those who delayed their treatment needed secondary surgical measures, due to the severity of inflammation and necrosis of the digital tissues. Conclusion: As the industrial sector develops, the use of HF is increasing more and more, leading to increase in incidences of HF-induced chemical burns. When treating chemical burns caused by HF, washing by copious amounts of normal saline, along with early removal of the nails, rather than calcium gluconate, seems to be a available method for preserving the shape and function of the digits and the nail. The education of patients regarding this subject should be empathized accordingly.