• Safety and Health at Work
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• v.10 no.4
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• pp.428-436
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• 2019

Background: Metalworking fluids (MWFs) are mixtures with inhalation exposures as mists, dusts, and vapors, and dermal exposure in the dispersed and bulk liquid phase. A quantitative risk assessment was performed for exposure to MWF and respiratory disease. Methods: Risks associated with MWF were derived from published studies and NIOSH Health Hazard Evaluations, and lifetime risks were calculated. The outcomes analyzed included adult onset asthma, hypersensitivity pneumonitis, pulmonary function impairment, and reported symptoms. Incidence rates were compiled or estimated, and annual proportional loss of respiratory capacity was derived from cross-sectional assessments. Results: A strong healthy worker survivor effect was present. New-onset asthma and hypersensitivity pneumonitis, at 0.1 mg/㎥ MWF under continuous outbreak conditions, had a lifetime risk of 45%; if the associated microbiological conditions occur with only 5% prevalence, then the lifetime risk would be about 3%. At 0.1 mg/㎥, the estimate of excess lifetime risk of attributable pulmonary impairment was 0.25%, which may have been underestimated by a factor of 5 or more by a strong healthy worker survivor effect. The symptom prevalence associated with respiratory impairment at 0.1 mg/㎥ MWF was estimated to be 5% (published studies) and 21% (Health Hazard Evaluations). Conclusion: Significant risks of impairment and chronic disease occurred at 0.1 mg/㎥ for MWFs in use mostly before 2000. Evolving MWFs contain new ingredients with uncharacterized long-term hazards.

• Korean Journal of Veterinary Research
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• v.42 no.2
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• pp.261-268
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• 2002

Bovine piroplasmosis caused by Theileria sergenti results in economic loss in the dairy industry. The majority of calves infected with T. sergenti in Korea harbor mixed populations with Buffeli, Chitose and Ikeda types. The T. sergenti types of the infected calves were examined to evaluate the effects of diminazene aceturate on their infection. To confirm the type of the T. sergenti infection, the allele-specific PCR was performed with the erythrocyte specimen from the 5 naturally infected calves. The dfferent allele-specific genes encoding the p32, p33 and 34, the immunodominant piroplasmin surface proteins, were amplified using the 3 sets of the oligonucleotide primers by PCR. The calves were treated with diminazene aceturate at the dose of 2mg/kg once intravenously and monitored for 12 months at one month intervals by the allele-specific PCR. Diminazene aceturate did not effect the Ikeda type infection. But diminazene aceturate effected the Chitose and Buffeli type infection reducing T. sergenti parasitemia. It is postulated that diminazene aceturate may effect the infection of the Chitose and Buffeli types, but not that of Ikeda type.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.5
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• pp.701-707
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• 2006

Disinfectant residual should be maintained to achieve biological stability during distribution of treated water. The wide distribution of retention times associated with storage and transport of water in a network and the reactivity of disinfectants make it difficult to maintain adequate residuals at critical locations. Rechlorination at some intermediate locations may reduce the total disinfectant dose while keeping residuals within specified limits throughout the water distribution system. In order to select the adequate location of rechlorination for achieving to maintain of residual chlorine throughout the distribution system, EPANET was used in this study. EPANET was well predicted chlorine transport and residual loss in the distribution system. Location of rechlorination was selected to maintain 0.4mg/L of residual chlorine throughout a water distribution system by field investigation and model simulation. The quantity of chlorine may reduced 36.7% and provided smooth residual between 0.42 and 0.60mg/L, when rechlorination would be used continuously at strategic location within the distribution system.

• Journal of Environmental Health Sciences
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• v.35 no.4
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• pp.259-268
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• 2009

This study was carried out to investigate the protective effect of Red Ginseng Saponins on 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induced toxicities in guinea pigs ($200{\pm}10$ g). Normal control (NC) group guinea pigs ($200{\pm}10$ g) received vehicle and saline, while the TCDD-treated (TT) group was given water-extract (WE), saponin fraction (SF) and non-saponin fraction (NSF). Korean red ginseng fractions were administered from 1 week before TCDD-exposure for 4 weeks. Body weight loss and deteriorated clinical parameters related to sugar metabolism and liver function such as lipase and AST, respectively, these were significantly reduced by both saponin and non-saponin fractions. However, increase of lipase was attenuated by the saponin fraction in a dose-dependent manner. Only AST was affected by the saponin fraction. The results suggest that saponins are active substances in the Korean red ginseng water extract against TCDD induced toxicities in Guinea pigs.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6321-6326
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• 2014

${\alpha}$-Methyl-n-butylshikonin (MBS), one of the active components in the root extracts of Lithospermum erythrorhizon, posses antitumor activity. In this study, we assess the molecular mechanisms of MBS in causing apoptosis of SW620 cells. MBS reduced the cell viability of SW620 cells in a dose-and time-dependent manner and induced cell apoptosis. Treatment of SW620 cells with MBS down-regulated the expression of Bcl-2 and up-regulated the expression of Bak and caused the loss of mitochondrial membrane potential. Additionally, MBS treatment led to activation of caspase-9, caspase-8 and caspase-3, and cleavage of PARP, which was abolished by pretreatment with the pan-caspase inhibitor Z-VAD-FMK. MBS also induced significant elevation in the phosphorylation of JNK and p38. Pretreatment of SW620 cells with specific inhibitors of JNK (SP600125) and p38 (SB203580) abrogated MBS-induced apoptosis. Our results demonstrated that MBS inhibited growth of colorectal cancer SW620 cells by inducing JNK and p38 signaling pathway, and provided a clue for preclinical and clinical evaluation of MBS for colorectal cancer therapy.

• Journal of Nutrition and Health
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• v.32 no.3
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• pp.318-326
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• 1999

Apoptotic cell death, characterized by DNA fragmentation and morphological changes, has previously been shown to occur in vascular endothelial cells cultured with hydrogen peroxide. The present study examined the induction of apoptosis by hydrogen peroxide and whether pyruvate, a key glycolytic intermediate and $\alpha$-keto-monocarboxylate, can inhibit the apoptotic effects in bovine pulmonary artery endothelial cells(BPAECs). Culture with 500uM hydrogen peroxide resulted in 30% cell death and induced morphological changes and DNA fragmentation. Cell injury was inhibited by the treatment with pyruvate. Pyruvate(0.1-5.0mM), and cell viability increased in a dose-dependent manner. In the presence of pyruvate(10~20mM), the viability was improved to over 95%. In contrast, treatment with lactate, a reduced form of phyuvate, did not protect against cell death oxidative stress-induced loss of viability and apoptosis was examined with $\alpha$-cyano-3-hydroxycinnarmate(COHC) as a selective mitochondrial monocarboxylate transport blocker. Incubation with COHC(500uM) did not significantly affect cell viability in the presence of hydrogen peroxide. The cytoprotection by pyruvate(3mM)against hydrogen peroxide stress was abolished by COHC. This indicates that the cytoprotection by pyruvate against oxidative stress in endothelial cells is mediated, at least in part, by mitochondrial pyruvate uptake and hence endothelial enerygetics. However, cytosolic mechanisms related, at least in part, by mitochondrial pyruvate uptake and hence endothelial energetics. However, cytosolic mechanisms related to the glutathione system may also contribute. The results suggest that pyruvate has therapeutic potential in the treatment of oxidative stress-induced cytotoxicity associated with increased apoptosis.

• Journal of Korean Neurosurgical Society
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• v.59 no.4
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• pp.400-404
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• 2016

We report a case of acute ischemic stroke involving both the anterior and posterior circulation associated with a persistent primitive trigeminal artery (PPTA), treated by endovascular revascularization for acute basilar artery (BA) occlusion via the PPTA. An otherwise healthy 67-year-old man experienced sudden loss of consciousness and quadriplegia. Magnetic resonance imaging showed an extensive acute infarction in the right cerebral hemisphere, and magnetic resonance angiography showed occlusion of the right middle cerebral artery (MCA) and BA. Because the volume of infarction in the territory of the right MCA was extensive, we judged the use of intravenous tissue plasminogen activator to be contraindicated. Cerebral angiography revealed hypoplasia of both vertebral arteries and the presence of a PPTA from the right internal carotid artery. A microcatheter was introduced into the BA via the PPTA and revascularization was successfully performed using a Merci Retriever with adjuvant low-dose intraarterial urokinase. After treatment, his consciousness level and right motor weakness improved. Although persistent carotid-vertebrobasilar anastomoses such as a PPTA are relatively rare vascular anomalies, if the persistent primitive artery is present, it can be an access route for mechanical thrombectomy for acute ischemic stroke.

• Advances in Traditional Medicine
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• v.7 no.3
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• pp.297-303
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• 2007

The ethyl acetate fraction (EAF) and n-butanol fraction (NBF) of ethanolic extract of Bacopa monnieri aerial parts were screened for hepatoprotective activity and in vivo antioxidant activity on ethanol-induced hepatotoxic rats. Ethyl acetate fraction was found to be more potent even though both the fractions were endowed with significant hepatoprotective activity. EAF and NBF were investigated for hepatoprotective activity in albino rats at 300 mg/kg, p.o. dose and compared with standard drug Silymarin (25 mg/kg, p.o.). Results show that both the fractions were effective in blunting ethanol-induced enhanced activities of serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, alkaline phosphatase, level of serum bilirubin (both total and direct), liver weight loss and was also effective in reducing ethanol-induced lipid peroxidation both in vitro and in vivo. Furthermore, the fractions could also enhance ethanol-induced suppressed activities of superoxide dismutase, catalase and decreased level of reduced glutathione. Results of hepatocellular damage caused by ethanol and its recovery by EAF and NBF, suggest that they might be considered as a potential source of natural hepatoprotective agents, which could be related to the free radical scavenging properties of saponins present in high concentration in the fractions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.456-459
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• 2003

Polychloroprene(CR) is well known as elastomer commonly utilized in the electrical. It is mainly used for cable jacket and insulator. The irradiation degradation property of polymer materials is very important to prevent unexpected accidents in the Nuclear Power Plant(NPP). The irradiation degradation is caused by the oxidation of polymer materials, and this oxidation is occurred by oxygen radical produced from air. In this study, we evaluate the oxidation properties of CR. CR is irradiated for 200, 400, 600, 1000 kGy radiation dose. The oxidation properties of irradiated CR are investigated by differential scanning calorimetry, dynamic mechanical properties and FT-IR/ATR. Glass transition temperature(Tg), decomposition onset temperature(DOT), loss modulus and mechanical tan $\delta$ values are compared together. The irradiation limit of CR in the NPP, is known for 500 kGy, and this is exactly matched with investigated results.

• Natural Product Sciences
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• v.22 no.3
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• pp.209-215
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• 2016

Kigelia africana (Lam.) Benth. (Bignoniaceae) is a flowering plants in South, Central and West Africa and commonly known as the sausage tree (Eng.); worsboom (Afr.); umVunguta, umFongothi (Zulu); Modukguhlu (North Sotho); Muvevha (Venda). The dried, powdered fruits are used as dressing for wounds and ulcers, haemorrhoids, rheumatism, purgative, skin-firming, lactation in breast-feeding mothers. The aim of this study is to investigate the cytotoxic and apoptotic potentials of 70% ethanolic extracts of Kigelia africana fruits in HCT116 human colon cancer cells. Treatment of Kigelia africana fruits with various concentrations resulted in a sequence of characteristic of apoptosis, including loss of cell viability and morphological changes. Flow cytometry analysis showed Kigelia africana fruits increased the sub-G1 phase (apoptosis) population. Apoptosis confirmed by annexin V-fluorescein isothiocyanate and propidium iodide double staining in HCT116 human colon cancer cell lines. Moreover, analysis of the mechanism indicated that Kigelia africana fruits showed an increased Bax and Bcl-2 expressions in a dose-dependent manner, resulting in activation of hallmarks of apoptotic events, caspase-3, caspase-9 and cleaved poly-ADP-ribose polymerase. This is the first report to demonstrate the cytotoxicity of Kigelia africana fruits on HCT116 human colon cancer cells.