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Degradation Characteristics of Oxalic Acid and Citric Acid by UV/H2O2 Oxidation (Oxalic Acid와 Citric Acid UV/H2O2에 의한 분해특성 조사)

  • Ha, Dong-Yun;Cho, Soon-Haing;Choi, Young-Soo;Kyung, Gyu-Seok;Kim, Dong-Hyun
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.7
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    • pp.1307-1318
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    • 2000
  • The purpose of this study is to investigate the degradation characteristics of oxalic acid and citric acid by $UV/H_2O_2$ oxidation. For this purpose, the effects of pH, $H_2O_2$ dosage and the concentration of each compounds on the degradation of oxalic acid and citric acid by $UV/H_2O_2$ were investigated. Oxalic acid was effectively degraded at the wavelength of 254 nm, while the degradation efficiency of citric acid was very low at the same wavelength. It was also found that both organic substances were not degraded by the injection of $H_2O_2$ only. The optimum pH of degradation of oxalic acid and citric acid was 4 and 4 to 6, respectively. In the case of $UV/H_2O_2$ oxidation, the degradation efficiency was increased by increasing $H_2O_2$ dosage. The degradation efficiency decreased when the dose of $H_2O_2$ exceeds 200 mg/L. From these results, it can be concluded that the optimum reaction conditions for the degradation of oxalic acid and citric acid by $UV/H_2O_2$ oxidation were pH 4 and 200mg/L of $H_2O_2$.

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Antibiotic Resistance of Escherichia Coli and Brevibacterium sp. Isolated from Livestock Waste and Disinfection Efficiency of Gamma-Ray Irradiation (축산폐기물에서 분리된 항생제 내성균 Escherichia coli....Brevibacterium sp.의 내성 특성 및 감마선 살균 효능)

  • Jang, Eun-Hee;Jung, Sang-Hyuk;Nam, Youn-Ku;Park, Woo-Shin;Lee, Myun-Joo;Kim, Tak-Hyun
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.7
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    • pp.676-681
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    • 2010
  • Antibiotic resistant bacteria were isolated from livestock wastes and the resistance patterns were investigated using various antibiotic agents. Also, a gamma ray was tested regarding the aspects of the effect on resistance pattern and the efficiency of disinfection. Among the isolates, Esherichia coli and Brevibacterium sp. showed the most serious resistance patterns. Esherichia coli had resistance against 9 agents whereas Brevibacterium sp. against 7 agents. It can be suggested from these results that the abuse of antibiotic agents will cause a serious mutation problem even to Esherichia coli which is ubiquitous in the ecosystem. Esherichia coli could be easily controlled but Brevibacterium sp. had a moderate resistance to the gamma ray under low doses. In the case of Brevibacterium sp, more than 2.0 kGy of a radiation dose will be required in order to achieve an enhanced efficiency of disinfection.

Aged garlic extract enhances exercise-mediated improvement of metabolic parameters in high fat diet-induced obese rats

  • Seo, Dae Yun;Lee, SungRyul;Figueroa, Arturo;Kwak, Yi Sub;Kim, Nari;Rhee, Byoung Doo;Ko, Kyung Soo;Bang, Hyun Seok;Baek, Yeong Ho;Han, Jin
    • Nutrition Research and Practice
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    • v.6 no.6
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    • pp.513-519
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    • 2012
  • Aged garlic extract (AGE) is known to have a protective effect against immune system, endothelial function, oxidative stress and inflammation. We examined the effects of exercise with and without aged garlic extract administration on body weight, lipid profiles, inflammatory cytokines, and oxidative stress marker in high-fat diet (HFD)-induced obese rats. Forty-five Sprague-Dawley rats were fed either a HFD (HFD, n = 40) or a normal diet (ND, n = 5) for 6 weeks and thereafter randomized into ND (n = 5), HFD (n = 10), HFD with AGE (n = 10), HFD with Exercise (n = 10), or HFD with Exercise+AGE (n = 10) for 4 weeks. AGE groups were administered at a dose of 2.86 g/kg body weight, orally. Exercise consisted of running 15-60 min 5 days/week with gradually increasing intensity. AGE (P<0.01), Exercise, and Exercise+AGE (P<0.001) attenuated body weight gain and food efficiency ratio compared to HFD. Visceral fat and liver weight gain were attenuated (P<0.05) with all three interventions with a greater effect on visceral fat in the Exercise+AGE than AGE (P<0.001). In reducing visceral fat (P<0.001), epididymal fat (P<0.01) and liver weight (P<0.001), Exercise+AGE was effective, but exercise showed a stronger suppressive effect than AGE. Exercise+AGE showed further additive effects on reducing visceral fat and liver weight (P<0.001). AGE significantly attenuated the increase in total cholesterol and low-density lipoprotein-cholesterol compared with HFD (P<0.05). Exercise+AGE attenuated the increase in triglycerides compared with HFD (P<0.05). Exercise group significantly decrease in C-reactive protein (P<0.001). These results suggest that AGE supplementation and exercise alone have anti-obesity, cholesterol lowering, and anti-inflammatory effects, but the combined intervention is more effective in reducing weight gain and triglycerides levels than either intervention alone.

Toxicity Assessment and Establishment Acceptable Daily Intake of Pyrimisulfan (피리미설판(Pyrimisulfan)의 독성평가와 일일섭취허용량 설정)

  • Jeong, Mi-Hye;Park, Kyung-Hun;Park, Jae-Eup;Kwack, Seung-Jon;Kim, Young-Bum;Han, Bum-Seok;Son, Woo-Chen
    • The Korean Journal of Pesticide Science
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    • v.15 no.2
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    • pp.208-217
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    • 2011
  • Pyrimisulfan is a herbicide. In order to register this new pesticide, the series of toxicity data on animal testing were reviewed to evaluate its hazards to consumers and also to determine its acceptable daily intake. Pyrimisulfan was excreted mostly by feces. It has low acute oral toxicity while it has no dermal, ocular irritation and skin sensitization (As the result of subchronic and chronic toxicity and carcinogenicity showed changes of hematology and liver.). Two-generation reproduction toxicity, genotoxicity, carcinogenicity and prenatal development toxicity were not proven. Therefore, the ADI for Pyrimisulfan is 0.1 mg/kg/ bw/day, based on the NOAEL of 10 mg/kg/ bw/day of 90-days repeated dose oral toxicity study in dogs while applying an uncertainty factor of 100.

Effect of Electric Conductivity and Potassium Level of the Culture Solution on the air Pollution Sensibility of Perillar Frutescens Suwon 16 (양액의 전기전도도 및 칼륨 수준이 들깨 수원 16호의 대기오염 지표성에 미치는 영향)

  • Kim, Jeong-Gyu;Lee, Yong-Bum;Koh, Kang-Suk
    • Korean Journal of Soil Science and Fertilizer
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    • v.29 no.4
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    • pp.411-418
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    • 1996
  • This experiment was conducted to investigate the effect of electric conductivity (EC) and potassium (K) concentration level in the culture solution on the growth and the air pollution monitoring capability of Perilla frutescens Suwon 16 which was recognized as a possible bioindicator for air pollution. The plants were exposed to $NO_2$, $O_3$, $SO_2$ and $NO_2+SO_2$ within a phytotron at $25^{\circ}C$ (day) or at $20^{\circ}C$(night) with 70% of relative humidity and evaluated the effect of EC and K level on the injury of the plants, The highest dry weights were gained as 16.3 g/plant at 0.5 dS/m of EC and as 32.3 g/plant at 100 and 200mg/l of K concentration, respectively. The diffusive resistances appeared as low values at 0.5 dS/m of EC and at 50, 100mg/l of K concentration. The increasing of the visible injury with increasing the dose of air pollutants could be taken at 0.5. 1.0 ds/m of EC and at 50, 100mg/l of K. The recommendable level of EC and K of the culture solution were 0.5-1.0 dS/m of electric conductivity. 50-100mg/l of K for the plant as an air pollutant biomonitor, when the 7th or 8th leaf was developed.

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Gamma Knife Radiosurgery for Brainstem Metastasis

  • Yoo, Tae-Won;Park, Eun-Suk;Kwon, Do-Hoon;Kim, Chang-Jin
    • Journal of Korean Neurosurgical Society
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    • v.50 no.4
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    • pp.299-303
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    • 2011
  • Objective : Brainstem metastases are rarely operable and generally unresponsive to conventional radiation therapy or chemotherapy. Recently, Gamma Knife Radiosurgery (GKRS) was used as feasible treatment option for brainstem metastasis. The present study evaluated our experience of brainstem metastasis which was treated with GKRS. Methods : Between November 1992 and June 2010, 32 patients (23 men and 9 women, mean age 56.1 years, range 39-73) were treated with GKRS for brainstem metastases. There were metastatic lesions in pons in 23, the midbrain in 6, and the medulla oblongata in 3 patients, respectively. The primary tumor site was lung in 21, breast in 3, kidney in 2 and other locations in 6 patients. The mean tumor volume was $1,517mm^3$ (range, 9-6,000), and the mean marginal dose was 15.9 Gy (range, 6-23). Magnetic Resonance Imaging (MRI) was obtained every 2-3 months following GKRS. Follow-up MRI was possible in 24 patients at a mean follow-up duration of 12.0 months (range, 1-45). Kaplan-Meier survival analysis was used to evaluate the prognostic factors. Results : Follow-up MRI showed tumor disappearance in 6, tumor shrinkage in 14, no change in tumor size in 1, and tumor growth in 3 patients, which translated into a local tumor control rate of 87.5% (21 of 24 tumors). The mean progression free survival was 12.2 months (range, 2-45) after GKRS. Nine patients were alive at the completion of the study, and the overall mean survival time after GKRS was 7.7 months (range, 1-22). One patient with metastatic melanoma experienced intratumoral hemorrhage during the follow-up period. Survival was found to be associated with score of more than 70 on Karnofsky performance status and low recursive partitioning analysis class (class 1 or 2), in terms of favorable prognostic factors. Conclusion : GKRS was found to be safe and effective for management of brainstem metastasis. The integral clinical status of patient seems to be important in determining the overall survival time.

Effects of Mume Fructus on the Rat Hypothyroidism Induced by PTU(6-n-propyl-2-thiouracil) (PTU(6-n-propyl-2-thiouracil)로 유발된 Rat 갑상선 기능저하증에 미치는 烏梅의 효과)

  • Choi, Jae Young;Roh, Seong Soo;Park, Ji Ha;Koo, Jin Suk;Seo, Bu Il
    • The Korea Journal of Herbology
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    • v.30 no.4
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    • pp.109-119
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    • 2015
  • Objectives : The aim of this study was to evaluate the effect of aqueous extracts of Mume Fructus(MF) on the 6-n-propyl-2-thiouracil(PTU)-induced rat hypothyroidism.Methods : Aqueous extracts of MF(yield = 19.38%) were administered, once per day for 42 days from 2 weeks before starting of PTU treatment as an oral dose of 300 and 150 ㎎/㎏(body weight), and hypothyroidism was induced by daily subcutaneous treatment of PTU 10 ㎎/㎏ for 28 days. The changes in the body weight, thyroid gland weights, liver weight, serum levels of thyroid hormone-thyroid stimulating hormone(TSH), tri-iodothyronine(T3) and thyroxine(T4), total cholesterol, low density lipoprotein(LDL), high density lipoprotein(HDL) and triglyceride (TG), aspartate aminotransferase(AST), alanine aminotransferase(ALT), liver antioxidant defense system-lipid peroxidation, H2O2, superoxide dismutase(SOD) and catalase(CAT) were examined with histopathology of thyroid glands and liver.Results : Results were compared with LevoT40.5 ㎎/㎏ treated rats. MF extracts recovered from the decreases in the body weight, liver weight, T3and T4, TG, liver CAT activities as results of PTU treatment. And MF extracts recovered from the increases of thyroid gland weights, TSH, HDL contents, liver H2O2, AST as results of PTU treatment. In addition, these PTU-induced histopathological changes in thyroid glands and liver related to hypothyroidism were dramatically decreased by treatment of both different dosages of MF extract, respectively.Conclusions : According to the above results, it is suggested that MF extracts have advantageous effects on the thyroid hormone productions with beneficial effects on the hypothyroidism related liver injuries mediated by the modulation on the antioxidant system.

Misuse of testosterone replacement therapy in men in infertile couples and its influence on infertility treatment

  • Song, Seung-Hun;Sung, Suye;Her, Young Sun;Oh, Mihee;Shin, Dong Hyuk;Lee, Jinil;Baek, Jeongwon;Lee, Woo Sik;Kim, Dong Suk
    • Clinical and Experimental Reproductive Medicine
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    • v.46 no.4
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    • pp.173-177
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    • 2019
  • Objective: We investigated the clinical characteristics of men with testosterone replacement therapy (TRT)-induced hypogonadism and its effect on assisted reproductive technology (ART) in infertile couples. Methods: This study examined the records of 20 consecutive male patients diagnosed with azoospermia or severe oligozoospermia (< 5 × 106/mL) who visited a single infertility center from January 2008 to July 2018. All patients were treated at a primary clinic for erectile dysfunction or androgen deficiency symptoms combined with low serum testosterone. All men received a phosphodiesterase 5 inhibitor and TRT with testosterone undecanoate (Nebido®) or testosterone enanthate (Jenasteron®). Patients older than 50 years or with a chronic medical disease such as diabetes were excluded. Results: The mean age of patients was 37 years and the mean duration of infertility was 16.3 ± 11.6 months. At the initial presentation, eight patients had azoospermia, nine had cryptozoospermia, and three had severe oligozoospermia. Serum follicle-stimulating hormone levels were below 1.0 mIU/mL in most patients. Three ongoing ART programs with female factor infertility were cancelled due to male spermatogenic dysfunction; two of these men had normal semen parameters in the previous cycle. After withholding TRT, serum hormone levels and sperm concentrations returned to normal range after a median duration of 8 months. Conclusion: TRT with high-dose testosterone can cause spermatogenic dysfunction due to suppression of the hypothalamic-pituitary-testicular axis, with adverse effects on infertility treatment programs. TRT is therefore contraindicated for infertile couples attempting to conceive, and the patient's desire for fertility must be considered before initiation of TRT in a hypogonadal man.

Alkaloids from Beach Spider Lily (Hymenocallis littoralis) Induce Apoptosis of HepG-2 Cells by the Fas-signaling Pathway

  • Ji, Yu-Bin;Chen, Ning;Zhu, Hong-Wei;Ling, Na;Li, Wen-Lan;Song, Dong-Xue;Gao, Shi-Yong;Zhang, Wang-Cheng;Ma, Nan-Nan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9319-9325
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    • 2014
  • Alkaloids are the most extensively featured compounds of natural anti-tumor herbs, which have attracted much attention in pharmaceutical research. In our previous studies, a mixture of major three alkaloid components (5, 6-dihydrobicolorine, 7-deoxy-trans-dihydronarciclasine, littoraline) from Hymenocallis littoralis were extracted, analyzed and designated as AHL. In this paper, AHL extracts were added to human liver hepatocellular cells HepG-2, human gastric cancer cell SGC-7901, human breast adenocarcinoma cell MCF-7 and human umbilical vein endothelial cell EVC-304, to screen one or more AHL-sensitive tumor cell. Among these cells, HepG-2 was the most sensitive to AHL treatment, a very low dose ($0.8{\mu}g/ml$) significantly inhibiting proliferation. The non-tumor cell EVC-304, however, was not apparently affected. Effect of AHL on HepG-2 cells was then explored. We found that the AHL could cause HepG-2 cycle arrest at G2/M checkpoint, induce apoptosis, and interrupt polymerization of microtubules. In addition, expression of two cell cycle-regulated proteins, CyclinB1 and CDK1, was up-regulated upon AHL treatment. Up-regulation of the Fas, Fas ligand, Caspase-8 and Caspase-3 was observed as well, which might imply roles for the Fas/FsaL signaling pathway in the AHL-induced apoptosis of HepG-2 cells.

The Effect of Tissue Plasminogen Activator on TGF-${\beta}1$ Pre-Treated Human Mesothelial Cell Line (TGF-${\beta}1$으로 자극한 사람중피세포주에서 조직플라스미노겐 활성제가 미치는 영향)

  • Lee, Jung-Lim;Jeon, Soo-Jin;Yoo, Young-Choon;Kim, Ji-Hye;Lee, Yu-Mi;Kwon, Sun-Jung;Son, Ji-Woong;Choi, Eu-Gene;Na, Moon-Jun
    • Tuberculosis and Respiratory Diseases
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    • v.70 no.5
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    • pp.405-415
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    • 2011
  • Background: In an effort to find alternative therapeutic agents to prevent excessive fibrosis as a sequela to complicated parapneumonic effusion or empyema, we examined the effect of tissue plasminogen activator (tPA) as a fibrinolytic agent combined with talc or transforming growth factor (TGF)-${\beta}1$ in a human pleural mesothelial cell line, MeT-5A. Methods: MeT-5A cells were stimulated with various doses of talc, doxycycline or TGF-${\beta}1$ for 24 h and then were treated with tPA for an additional 24 h. Cell viability was measured by MTT assay. The production of interleukin (IL)-8 and vascular endothelial growth factor (VEGF) in the culture supernatants was measured by ELISA. Real-time PCR was carried out for measurement of type I collagen mRNA. Results: MeT-5A cells treated with talc showed a dose-dependent increase in production of IL-8. Talc also increased production of type I collagen mRNA at low doses, but talc did not influence the induction of VEGF. Addition of tPA to talc-stimulated cells showed further increases in the production of IL-8, but tPA did not influence the production of VEGF or type I collagen mRNA. TGF-${\beta}1$ increased the production of both VEGF and collagen type I mRNA, both of which were effectively inhibited by additional tPA treatment in MeT-5A cells. Conclusion: TGF-${\beta}1$ is a potent inducer of collagen synthesis without induction of IL-8 in MeT-5A cells. Addition of tPA after TGF-${\beta}1$ stimulation inhibited further fibrosis by direct inhibition of collagen mRNA synthesis as well as by inhibition of VEGF production.