• Title/Summary/Keyword: Characteristics Toxicity

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Immobilization Characteristics of Hexavalent Chromium Contaminated Soils Treated with Phosphate and Chromium Reducing Agent (크롬환원제와 인산염으로 처리된 6가 크롬 오염토양의 고정화)

  • Lee, Eui-Sang
    • Journal of Environmental Impact Assessment
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    • v.16 no.1
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    • pp.27-33
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    • 2007
  • Hexavalent chromium-contaminated soils are encounted at many unregulated discharge and improper handling of wastes from electroplating, leather tanning, steelmaking, corrosion control, and wood preservation industries. Contamination of hexavalent chromium in the soil is a major concern because of its toxicity and threat to human life and environment. Current technologies for hexavalent chromium-contaminated soil remediation are usually costly and/or cannot permanently prohibit the toxic element from entering into the biosphere. Thus, as an alternative technique, immobilization is seen as a cost-effective and promising remediation technology that may reduce the leachable potential of hexavalent chromium. The purpose of this paper is to develope an immobilization technique for the formation of the geochemically stabilized hexavalent chromium-contaminated soil from the reactions of labile soil hexavalent chromium forms with the added soluble phosphate and chromium reducing agent. From the liquid phase experiment, reaction order of chromium reducing agent, soluble phosphate, alkali solution shows the best removal efficiency of 95%. In addition, actual soil phase experiment demonstrates up to 97.9% removal efficiency with 1:1 molar ratio of chromium reducing agent and soluble phosphate. These results provide evidence for the potential use of soluble phosphate and chromium reducing agent for the hexavalent chromium-contaminated soil remediation.

Serum 25-Hydroxyvitamin D Status in Wintertime in Premenopausal Working Women (일부 폐경전 성인직장여성의 겨울철 혈청 25-Hydroxyvitamin D상태에 관한 연구)

  • Lim, Hwa-Jae;Kim, Jung-In
    • Journal of Nutrition and Health
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    • v.39 no.7
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    • pp.649-660
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    • 2006
  • This study was performed to estimate serum 2S-hydroxyvitamin D (25-OHD) level in wintertime and to evaluate the relationship between serum 25-OHD level and associated factors in 50 premenopausal working women aged 30-49 y in Busan. The serum 25-OHD level was measured by radioimmunoassay. Data for physiological characteristics, lifestyle factors, physical activity and nutrient intake was assessed by questionnaire including information about outdoor activity time, daily activity diary and 24hr recall method. The mean vitamin D intake was $4.24{\mu}g$, which corresponded to 84.9% of the Korean RDA. The mean level of serum 25-OHD was 25.7 ng/mL. Vitamin D deficiency (25-OHD < 7nmol/L) and toxicity $(25-OHD{\geq}75\;nmol/L)$ were not found in the subjects. However, the prevalence of vitamin D insufficiency (25-OHD < 15 nmol/L) and hypovitaminosis D (25-OHD < 30 nmol/L) were 12% and 60% respectively. The serum 25-OHD level showed positive significant correlations with the duration of outdoor activity per weekdays (p < 0.05). Our findings suggest that hypovitaminosis D was common in the subjects in wintertime. So nutritional education for increasing outdoor activities is needed for premenopausal working women to increase vitamin D status in wintertime.

Predictive Value of Baseline Plasma D-dimers for Chemotherapy-induced Thrombocytopenia in Patients with Stage III Colon Cancer: A Pilot Study

  • Tanriverdi, Ozgur
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.293-297
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    • 2013
  • Background: : Chemotherapy-induced thrombocytopenia (CIT) is an important cause of morbitity in patients with cancer. Aim: To investigate the effect of the baseline plasma D-dimer level, an important marker for thrombotic activity, on chemotherapy-induced thrombocytopenia in patients with stage III colon cancer. Materials and Methods: A total of 43 (28 men) eligible patients were divided into two groups according to whether they exhibited chemotherapy-induced thrombocytopenia: Group 1 (n=21) and Group 2 (n=22). Comparison was made using demographic, histopathologic, and laboratory variables. Additionally, baseline plasma D-dimer levels underwent receiver operation characteristics curve analysis, and areas under the curve were calculated. Sensitivity, specificity, and positive and negative likelihood rates were then determined. Results: The incidence of chemotherapy-induced thrombocytopenia had a significant correlation with baseline platelet count (r=0.568, P=0.031) and baseline plasma D-dimer levels (r=0.617, P=0.036). When the cut-off point for the latter was set as 498 ng/mL, the area under the curve was 0.89 (95%CI: 0.74-0.93), the sensitivity was 91.4%, the specificity was 89.7%, the positive likelihood rate was 3.64 and the negative likelihood rate was 0.24 for chemotherapy-induced thrombocytopenia diagnosis. Conclusions: The baseline level of plasma D-dimer could help to differentiate high-risk patients for chemotherapy-induced thrombocytopenia.

A Study on the Micropollutants and Removal of Micropollutants Contained in Road Runoff (노면배수에 함유된 미량오염물질 및 제거에 관한 연구)

  • Kim, Boo-Gil;Park, Heung-Jai;Jang, Seong-Ho
    • Journal of Environmental Science International
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    • v.18 no.2
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    • pp.215-219
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    • 2009
  • Micropollutants, which can be caused by imperfect combustion, are toxic chemical compound that flows into the river system after being contained in road runoff, a non-point source pollutant and accumulates in the body. The micropollutants that have characteristics such as toxicity, persistence, bio-accumulation, long-range transportation behave so similarly to micro particles that they can be removed by means of filtration or absorption. This study has examined the kinds and concentrations of micropollutants contained in deposited road particles. It has revealed that the kinds of micropollutants contained in the clarified supernatant liquid of deposited road particles are heavy metals and polycyclic aromatic hydrocarbons(PAHs) composed of two or three benzene rings, including naphthalene and acenaphthalene. Their concentrations have been shown to be low, with 0.418 mg/L, 0.058 mg/L, 0.104 mg/L, 0.014 mg/L, 0.00075 mg/L for Zn, Pb, Cu, Cr, Cd, respectively and 0.00156 mg/L and 0.00184 mg/L for naphthalene and acenaphthalene.

The involvement of oxygen free radicals in the onset of aging (노화에 미치는 산소 유리라디칼에 관한 연구동향)

  • Kim, Jung-Sang;Na, Chang-Su;Kim, Young-Kon
    • Korean Journal of Oriental Medicine
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    • v.3 no.1
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    • pp.229-239
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    • 1997
  • The superoxide anion radical$(O_2)$ poses a threat to macromocules and cell organelles of the living cells. This toxicity damage to all groups of proteins results in loss of enzyme function concerned with metabolism and ion transport, and peroxidation of unsaturated fatty acids and cholesterol results in a change of permeability characteristics of the membrane, and oxidative of nucleic acids results in genomic damage and thereby cause mutation, potential carcinogenesis and somatic damage that produce cellular aging Superoxide dismutase(SOD) has received substantial attention as a potential therapeutic agent. It has been investigated as a possible agent for the prevention of ontogenesis, the reduction of cytotoxic effect of anticancer drugs, and protection against damage in ischemic tissue. It is suggest that $O_2$ is concerned with cellular aging, thereafter we need to investigate herb that activated to SOD.

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Effects of Catalyst Granule Failure in Monopropellant Satellite Thruster (단일추진제 위성추력기에서 촉매 파손에 의한 영향)

  • Hwang, Chang-Hwan;Lee, Sung-Nam;Baek, Seung-Wook;Kim, Su-Kyum;Yu, Myoung-Jong
    • Journal of the Korean Society of Propulsion Engineers
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    • v.15 no.6
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    • pp.7-14
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    • 2011
  • Various sizes of hydrazine monopropellant thruster have been used on satellite and space launcher vehicle. The test and handling procedure of hydrazine monopropellant thruster are usually difficult because of the toxicity of hydrazine and its decomposition product gases. Therefore, the numerical analysis can help understand the effects of various design parameters and can reduce the time as well as expenses. In this study, the numerical analysis is performed by modelling the catalyst bed as one dimensional porous medium. Thereby, resulting physical phenomena are examined by considering the variation of catalyst bed characteristics incurred by catalyst granule failure.

Evaluation of Azithromycin Prescriptions for Pediatric Patients (소아환자에서 아지스로마이신 처방 분석)

  • Oh, Eun Kyoung;Rhew, Ki Yon
    • Korean Journal of Clinical Pharmacy
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    • v.26 no.2
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    • pp.115-120
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    • 2016
  • Background: Azithromycin has broad spectrum and is effective to treat several bacterial respiratory tract infection. It is also relatively safe and tolerable to pediatric patient. Careful use of azithromycin is also required for the prescribers because it could cause cardiovascular toxicity (QTc prolongation) and ototoxicity. There has been no study on duration of azithromycin use in pediatric patients in Korea. Methods: The outpatient sample data on the azithromycin prescription was obtained from Korean health insurance review and assessment service. The characteristics of azithromycin prescription were analyzed with two different years (2011 and 2014). Results: Total 4,215 cases were analyzed. The azithromycin was prescribed the most frequently in the children (73.2% in 2011 and 62.5% in 2014) and for the condition of bronchopneumonia (28.7% in 2011 and 21.7% in 2014) in both years. The duration of prescribed for azithromycin has significantly different between 2011 and 2014. In 2014, 94.3% of prescription were indicated less than 5 days, but 86.6% were in 2011. Acute bronchiolitis and bronchopneumonia prescriptions more longer duration of treatment compared with acute bronchitis and others. Conclusion: The pattern of prescribing azithromycin has been changed for the treatment of several infectious diseases in pediatric patients. The rate of appropriate duration of azithromycin treatment has increased.

Effects of Natural Organic Matter (NOM) on Cr(Ⅵ) reduction by Fe(II) (Fe(II)을 이용한 Cr(Ⅵ) 환원시 천연유기물의 영향)

  • 한인섭
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1999.10a
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    • pp.81-84
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    • 1999
  • The aqueous geochemical characteristics of Cr(III) and Cr(Ⅵ) in environmental systems are very different from one another: Cr(Ⅵ) is highly soluble, mobile and toxic relative to Cr(III) Reduction of Cr(Ⅵ) to Cr(III) are beneficial in aquatic systems because of the transformation of a highly mobile and toxic species to one having a low solubility in water, thus simultaneously decreasing chromium mobility and toxicity. Fe(II) species are excellent reductants for transforming Cr(Ⅵ) to Cr(III), and in addition, keeping Cr(III) concentrations below the drinking water standard of 52 ppb at pH values between 5 and 11. Investigations of the effects of NOM on Cr(Ⅵ) reduction are for examining the feasibility of using ferrous iron to reduce hexavalent chromium in subsurface environments. Experiments in the presence of soils, however, showed that the solid phase consumes some of the reducing capacity of Fe(II) and makes the overall reduction kinetics slower. The soil components bring about consumption of the ferrous iron reductant. Particular attention is devoted to the complexation of Fe(II) by NOM and the subsequent effect on Cr(Ⅵ) reduction. Cr(Ⅵ) reduction rate by Fe(II) was affected by the presence of NOM (humic acid), The effects of humic acid was different from the solution pH values and the concentration of humic acid. It was probably due to the reactions between humic acid and Cr(Ⅵ), humic acid and Fe(II), and between Cr(Ⅵ) and Fe(II), at each pH.

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Recent Advances and Future Strategy in Gene Delivery System (유전자 수송계의 현재까지의 연구동향 및 앞으로의 개발전략)

  • Choi, Woo-Jeong;Kim, Chong-Kook
    • Journal of Pharmaceutical Investigation
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    • v.30 no.1
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    • pp.1-12
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    • 2000
  • Gene therapy is a method for the treatment of diseases with introducing the gene-engineered materials into a patient with gene-deficiency disease (e.g. cystic fibrosis) or cancer to produce a therapeutic protein in a patient's cells. Successful gene therapy requires establishing both gene expression systems and delivery systems. Viral and non-viral vectors have been used for gene delivery. Viral vectors have a high transfection efficiency, but are limited in relations to issues of safety, toxicity and immunogenecity. Non-viral vectors are easy to prepare and relatively safe. However, non-viral vectors have a low transfection efficiency. Cationic liposomes are the most available among non-viral vectors. Cationic liposomes have been used to transfect cells both in vitro and in vivo experiments. Besides, several formulations containing cationic lipid are being used in clinical trials in cases of cystic fibrosis or cancer. A crucial subject to the further development of gene delivery vectors will be a long-term gene expression with following characteristics; protecting and deliverying DNA efficiently, non-toxic and non-immunogenic, and easy to produce in large scale.

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Deposition of Inhaled Smoke Particles Produced by Fire (화재에 의한 흡입연기의 호흡기 내 침착에 관한 연구)

  • Goo, Jae-Hark
    • Fire Science and Engineering
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    • v.21 no.2 s.66
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    • pp.64-73
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    • 2007
  • The absorption characteristics of hazardous materials onto human body and defense mechanism differ from each other region within the respiratory tracts, thus adverse health effects of inhaled smokes are associated with not only the concentration but also the location of the particles deposited. In this work, the deposition fraction per surface area and the deposition sites of the smoke particles in human respiratory tracts for each rest and light exercise conditions together with oral and nasal breathing were calculated by using segmental volume tracking method. The results would be used for deriving the amount of absorption of hazardous materials onto human body, thus contribute to the health risk assessments of inhaled fire smokes.