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Removal of Ionic and Non-ionic Pharmaceuticals Using Granular Activated Carbon (입상활성탄을 이용한 이온성 및 비이온성 의약품의 제거)

  • Oh, Hee-Kyong;Kagawa, Chie;Urase, Taro;Simazaki, Dai;Kunikane, Shoichi
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.11
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    • pp.1192-1197
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    • 2006
  • Adsorbability of ionic and nonionic pharmaceuticals was studied using granular activated carbon(GAC). In a batch adsorption test of muticomponent solution, 500 mg/L of GAC dose removed all target compounds between 94 and 98% at initial concentration of 10 ${\mu}g/L$. Adsorption of ionic pharmaceuticals increased as pH was lowered toward to pKa, however adsorption capacity of nonionic pharmaceuticals showed insignificant variation with the changing pH. The enhanced adsorption capacity of ionic pharmaceuticals at lower pH was attributed to the corresponding increase in the molecular form of ionic pharmaceuticals with carboxylic group at low pH. In addition, decrease of pH increased hydrogen ion concentration in the bulk solution and the protons bound to the available sites on the carbon enhanced the removal of the ionic pharmaceuticals from solution. After 40 days of continuous operation, GAC column showed the removal of target compounds were removed by $93{\sim}99%$ at 15 min of EBCT mainly due to adsorption mechanism of GAC. At shorter EBCT than 15 min, breakthrough of CA, IBP and GFZ occurred earlier than the other ionic and nonionic pharmaceuticals. effect of EBCT on adsorption of nonionic pharmaceuticals was greater than ionic ones. This study showed that persitent pharmaceuticals found in drinking water treatment could be effectively controlled by adsorption in GAC process.

Inactivation of Infectious Cryptosporidium parvum by Various Disinfectants (다양한 소독제에 의한 감염성 크립토스포리디움 불활성화율 평가)

  • Byun, Seung-Heon;Lee, Mok-Young;Cho, Eun-Ju;Yoon, Tae-Ho;Kim, Tae-Ho;Han, Sun-Hee
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.5
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    • pp.533-539
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    • 2007
  • Cell culture infectivity assay using HCT-8 cell was combined with most-probable-number technique to evaluate the inactivation of Cryptosporidium parvum by various disinfectants, including chlorine, ozone, and UV light. The assay was demonstrated to be as sensitive as animal infectivity assay, which has been considered the "gold standard" for assessing Cryptosporidium oocyst infectivity, and a valuable tool to evaluate inactivation of C. parvum by disinfectants. Bench-scale inactivation study showed that at the condition of $5^{\circ}C$ and pH 7.0, CT value of $1,250mg{\cdot}min/L$ by chlorine and $16mg{\cdot}min/L$ by ozone were required to achieve approximately 1.0 log inactivation of C. parvum, suggesting that even ozone could not be sufficient to inactivate C, parvum at low. temperature. Unlike chlorine and ozone, UV light is very effective to inactivate C. parvum, regardless of temperature. A UV light dose of 2 $mJ/cm^2$ provided at least 3 log inactivation of C. parvum.

Fluoride Removal from Aqueous Solution Using Thermally Treated Pyrophyllite as Adsorbent (고온 처리된 납석을 흡착제로 이용한 용액상의 불소 제거)

  • Kim, Jae-Hyun;Song, Yang-Min;Kim, Song-Bae
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.2
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    • pp.131-136
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    • 2013
  • The aim of this study was to investigate the removal of fluoride using thermally treated pyrophyllite as adsorbent. Sorption experiments were conducted under batch conditions to examine the effects of adsorbent dose, reaction time, initial fluoride concentration and solution pH on fluoride removal. In the experiments, the pyrophyllite thermally treated at different temperatures [untreated (P-U), $400^{\circ}C$ (P-400), $600^{\circ}C$ (P-600)] were used. Results showed that the adsorption capacity was in the order of P-400 > P-U > P-600. The XRD analysis indicated that both P-U and P-400 were composed of quartz, dickite and pyrophyllite while P-600 was quartz. The BET analysis showed that the specific surface area was in the order of P-600 > P-400 > P-U. Kinetic data showed that fluoride sorption to P-400 arrived at equilibrium around 24 h. Equilibrium test demonstrated that the maximum sorption capacity of P-400 was 0.957 mg/g. In addition, fluoride removal by P-400 was not sensitive to solution pH between 4 and 10. However, fluoride removal decreased considerably at highly acidic (pH < 4) and alkaline (pH > 10) conditions. This study demonstrates that pyrophyllite could be used as a low-cost adsorbent for fluoride removal from aqueous solution.

Evaluation of Biological Effects of Low Concentrations of Mercury Chloride (II) and Ionizing Radiation in the Prepubertal Male Rats (미성숙 웅성 흰쥐를 이용한 이온화 방사선 조사 및 저농도 염화수은(II)의 음용에 따른 위해성 비교 평가)

  • Kim Ji Hyang;Kim Jin Kyu;Yoon Yong Dal
    • Korean Journal of Environmental Biology
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    • v.22 no.3
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    • pp.411-418
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    • 2004
  • Mercury, one of the most diffused and hazardous organ-specific environmental contaminants, exists in a wide variety of physical and chemical states. The murcury with the nature which evaporates easily can cause an acute or chronic mercury poisoning to workers at mercury-handling workplaces. Although many studies indicate that mercury induces a deleterious damage, little has been reported from the investigations of mercury effects at surrounding levels in living things. The purpose of this study was to evaluate the biological effects of mercury chloride and ionizing radiation. Prepubertal male F344 rats were administered mercury chloride in drinking water throughout the experimental period or were given wholebody irradiation with a dose of 6.5 Gy. The amount changed of body weight during the experimental period showed a 4.9% rise in the mercury-treated group and 14.4% decline in the irradiated group compared with the level of the control group. The results of hematological analysis (red blood cells, white blood cells, hemoglobin, and hematocrit) indicated the differential effects of mercury chloride and ionizing radiation. However the concentration of cortisol as assessed by radioimmunoassay increased in both of the groups. Relative expressions of mRNA related to mitochondrion-mediated apoptosis were investigated using semiquantitative reverse transcription polymerase chain reaction on gonad and urinary organs of the experimental groups. While the expression of Bcl-2 mRNA exhibited different patterns depending on the organs or the experimental groups, both of the experimental groups showed a conspicuous expressions of Bax mRNA. In conclusion, the target organ of mercury chloride seems to be a urinary organ and the pattern of damage induced by mercury chloride differs from that by ionizing radiation.

Development of Ice Cream with Improved Microbiological Safety and Acceptable Organoleptic Quality Using Irradiation (감마선 이용 미생물학적 및 관능적 품질이 우수한 아이스크림의 개발)

  • Kim, H.J.;Jang, A.;Ham, J.S.;Jeong, S.G.;Ahn, J.N.;Byun, M.W.;Jo, C.
    • Journal of Animal Science and Technology
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    • v.49 no.4
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    • pp.515-522
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    • 2007
  • To develop the manufacturing method of ice cream with microbiologically safe and proper sensory quality using irradiation for sensitive consumer, 3 different flavors, which were resistant to their flavors against irradiation, were selected and used for ice cream manufacturing to reduce the irradiation-induced off-flavor problem. The general composition was not different among treatments. Total aerobic bacteria were detected as 2.38, 1.23, 1.38, and 1.15 log CFU/g level in ice cream with control(no flavor added), spearmint, mint, and citrus flavor, respectively. No viable cells were observed by irradiation at 1 kGy except for the control. Sensory evaluation indicated that the irradiated ice cream with spearmint flavor at 1 kGy and citrus flavor at 3 kGy had higher overall acceptability. Therefore, a low dose irradiation (less than 3 kGy) with mint or citrus flavors may enhance the safety of ice cream with proper sensory quality for sensitive consumer.

Effects on EDC-like farming chemicals in aquatic Organism (환경생물에 대한 내분비교란물질 의심 농약의 영향)

  • Kim, Hyun-Woo;Park, Kun-Ho;Park, Jin-Hong;Jin, Hua;Kim, Joon-Seong;Eu, Gook-Jong;Cho, Hyun-Sun;Kang, Ga-Mi;Lee, Myung-Sung;Song, Byung-Hoon;Shin, Jin-Sup;Cho, Maing-Haing
    • The Korean Journal of Pesticide Science
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    • v.7 no.3
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    • pp.188-197
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    • 2003
  • Endocrine disrupting chemicals (EDCs) can alter hormone regulation that control reproductive system in animals. The effects of endosulfan, molinate, and alachlor that suspected to have examined disruption EDCs effect on a fish species of interest, Xiphophorus helleri (swordtail fish), were studied using vitellogenin (Vtg) and aromatase as diagnostic biomarkers. Induction of Vtg proteins was detected by RT-PCR in male fish treated with alachlor, and mixture of endosulfan and molinate in dose response manner. Also, induction of aromatase was detected by RT-PCR in male fish treated with alachlor, endosulfan, and mixture of endosulfan and molinate in sinlilar manner. In this study, swordtail fish exposed to endosulfan or molinate individually did not show any adverse effects. However, Vtg and aromatase expressions and apoptosis were detected in swordtail. fish exposed to the mixture of endosulfan and molinate. These results suggested that low concentrations of mixture of molinate and endosulfan individually do not affect swordtail fish, but may influence genital system, and induce apoptosis.

Hepatoprotective Effects of Pig Placental Hydrolysates on Liver Damage-induced Rats by Injecting Carbon Tetrachloride (사염화탄소 주입으로 간손상을 유발시킨 백서에서 돈태반가수분해 물 투여가 간기능 보호에 미치는 영향)

  • Park, Sun-Young;Kim, Da-Sol;Kang, Sun-A;Park, Sun-Min
    • Journal of Applied Biological Chemistry
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    • v.55 no.2
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    • pp.109-115
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    • 2012
  • The aim of this study was to determine hepatoprotective effects of pig placenta hydrolysates (PLA) on liver damage-induced rats. Sprague Dawley rats were subcutaneously injected with carbon tetrachlorides and divided into 4 groups: negative control (DMSO treated), two PLA treated groups, low dosage of PLA (LPLA; 300 mg/kg body weight) and high dosage of PLA (HPLA; 1000 mg/kg body weight), and silymarin treated group (80 mg/kg body weight). Rats in each group orally received assigned compounds for 3 weeks. For the normal control group vehicle (corn oil) was injected. After 3 weeks, liver and spleen weights were greater in the two PLA and silymarin groups than the negative control group. After bromosulfalein (BSP) treatment, the clearance rates were in the descending order of negative control > LPLA > HPLA = silymarin and serum BSP levels exhibited the opposite trends of the clearance rates. Serum levels of aspartate aminotransferase, alanine aminotransferase, triglyceride, and cholesterol lowered with PLA in a dose-dependent manner. The decrease with HPLA was similar to that with silymarin. In addition, triglyceride, cholesterol, lipid peroxides levels in the liver decreased in HPLA and silymarin compared to the negative control. The liver morphometry was improved in HPLA- or silymarin-treated rats in comparison to the negative control. In conclusion, HPLA administration ameliorated the hepatotoxicity as much as silymarin in rats injected with carbon tetrachlorides.

Beneficial Roles of Azospirillum as Potential Bioinoculant for Eco-Friendly Agriculture (친환경농업을 위한 유용미생물 Azospirillum의 효율적 이용)

  • Gadagi, Ravi;Park, Myoung-Su;Lee, Hyoung-Seok;Seshadri, Sundaram;Chung, Jong-Bae;Sa, Tong-Min
    • Korean Journal of Soil Science and Fertilizer
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    • v.36 no.5
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    • pp.290-303
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    • 2003
  • Modern agriculture has been heavily dependent on chemical fertilizers to meet the food demands of ever increasing population. Progressive depletion of major plant nutrients in soil due to intensive cultivation practices has also necessitated the use of higher dose of chemical fertilizers particularly in soils where the organic matter content is very low. Indiscriminate use of chemical fertilizers and pressure on agriculturists to enhance per area crop yields has led to fast depletion of fossil fuel resources with concomitant increase in the prices of chemical fertilizers and also led to environmental pollution. Hence, the current trend throughout the world is to explore the possibility of using alternate nutrient sources or increasing the efficiency of chemical fertilizers by supplementing them with organic fertilizers and bioinoculants comprising largely microbes like, bacteria, fungi, algae etc to enhance nitrogen and phosphates in the soil thus creating a sustainable agricultural environment. Among the different microbial inoculants or biofertilizers, Azospirillum could be a potential candidate due to its non specific host root colonization. It had the capability to fix $N_2$ in wide pH regimes and even in presence of combined nitrogen. Azospirillum inoculation can increase the crop yield to 10-25% and substitute 25% of recommended doses of nitrogenous fertilizers. Apart from nitrogen fixation, Azospirillum is also involved in the root improvement, the activity which was attributed to an increase in the rate of water and mineral uptake by roots. The ability of Azospirillum to produce phytohormones was reported to enhance the root respiration rate, metabolism and root proliferation. They have also been reported to produce polyhydroxybutyrate, that can be used as a biodegradable thermosplastic. A lot of studies have addressed improvements in enhancing its efficiency to fix nitrogen fixation and hormone production.

Hypofractionated intensity-modulated radiotherapy in patients with localized prostate cancer: a preliminary study

  • Kang, Hye Jin;Kay, Chul-Seung;Son, Seok Hyun;Kim, Myungsoo;Jo, In Young;Lee, So Jung;Lee, Dong Hwan;Suh, Hong Jin;Choi, Yong Sun
    • Radiation Oncology Journal
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    • v.34 no.1
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    • pp.45-51
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    • 2016
  • Purpose: The aim of this work was to assess the efficacy and tolerability of hypofractionated intensity-modulated radiotherapy (IMRT) in patients with localized prostate cancer. Materials and Methods: Thirty-nine patients who received radical hypofractionated IMRT were retrospectively reviewed. Based on a pelvic lymph node involvement risk of 15% as the cutoff value, we decided whether to deliver treatment prostate and seminal vesicle only radiotherapy (PORT) or whole pelvis radiotherapy (WPRT). Sixteen patients (41%) received PORT with prostate receiving 45 Gy in 4.5 Gy per fraction in 2 weeks and the other 23 patients (59%) received WPRT with the prostate receiving 72 Gy in 2.4 Gy per fraction in 6 weeks. The median equivalent dose in 2 Gy fractions to the prostate was 79.9 Gy based on the assumption that the ${\alpha}/{\beta}$ ratio is 1.5 Gy. Results: The median follow-up time was 38 months (range, 4 to 101 months). The 3-year biochemical failure-free survival rate was 88.2%. The 3-year clinical failure-free and overall survival rates were 94.5% and 96.3%, respectively. The rates of grade 2 acute genitourinary (GU) and gastrointestinal (GI) toxicities were 20.5% and 12.8%, respectively. None of the patients experienced grade ${\geq}3$ acute GU and GI toxicities. The grade 2-3 late GU and GI toxicities were found in 8.1% and 5.4% of patients, respectively. No fatal late toxicity was observed. Conclusion: Favorable biochemical control with low rates of toxicity was observed after hypofractionated IMRT, suggesting that our radiotherapy schedule can be an effective treatment option in the treatment of localized prostate cancer.

Nitric oxide(NO) mediating non-adrenergic non-cholinergic(NANC) relaxation in the boar retractor penis muscle I. Mediators of nonadrenergic, noncholinergic relaxation of porcine retractor penis muscle : nitric oxide and vasoactive intestinal polypeptide (Nitric oxide에 의한 수퇘지 음경후인근의 비아드레날린 비콜린 동작성 이완 I. 돼지 음경후인근의 비아드레날린 비콜린성 이완을 매개하는 신경전달물질 : nitric oxide와 vasoactive intestinal polypeptide)

  • Mun, Kyu-whan;Kim, Jeum-yong;Kim, Tae-wan;Kang, Tong-mook;Yang, Il-suk
    • Korean Journal of Veterinary Research
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    • v.35 no.3
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    • pp.447-458
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    • 1995
  • This study was carried out to characterize nonadrenergic, noncholinergic(NANC) relaxation of porcine retractor penis(PRP) muscle induced by electrical field stimulation(EFS) and to investigate the actions of niric oxide(NO) and vasoactive intestinal polypeptide(VIP) as candidates for NANC neurotransmitters. Biphasic relaxations of PRP muscle were induced by EFS to NANC nerve. Rapid-phase relaxation was observed at low frequency(0.5-16Hz) and slow-phase relaxation followed during high frequency(8-60Hz). Both relaxations were frequency-dependent and TTX($1{\times}10^{-6}M$)-sensitive. L-NAME($2{\times}10^{-5}M$) inhibited the rapid-phase relaxation, but not the slow-phase relaxation. The inhibition of the rapid-phase relaxation with L-NAME was reversed by L-arginine ($1{\times}10^{-3}M$) but not by D-arginine($1{\times}10^{-3}M$). Methylene blue($4{\times}10^{-5}M$) reduced the rapid-phase relaxation. Exogenous No(ExoNO, $1{\times}10^{-5}-1{\times}10^{-4}M$) induced dose-dependent relaxations of PRP muscle. Oxyhemoglobin($5{\times}1^{-5}M$) blocked the relaxation induced by ExoNO and inhibited EFS-induced relaxation. Hydroquinone($1{\times}10^{-4}M$) also abolished the relaxation induced by ExoNO, but did not affect EFS-induced relaxation. L-NAME resistant slow-phase relaxation to EFS was inhibited by ${\alpha}$-chymotrypsin(2.5 U/ml). Both methylene blue($4{\times}10^{-5}M$) and Nethylmaleimide($1{\times}10^{-4}M$) reduced the slow-phase relaxation by EFS. [4-Cl-D-$Phe^6$, $Leu^{17}$]-VIP($3{\times}10^{-6}M$) inhibited the slow-phase relaxation by EFS. External applications of VIP ($1{\times}10^{-7}M$) caused relaxations that were simillar to the L-NAME resistant slow-phase relaxations induced by EFS, and relaxant effects of exogenous VIP were blocked by ${\alpha}$-chymotrypsin(2.5 U/ml).

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