Impact of Irradiation Time on the Hydrolysis of Waste Activated Sludge by the Dielectric Heating of Microwave

Tae Joo Park,Im Gyu Byun,Jae Ho Lee,Ji Sung Lim,Jeong Min Lee 대한환경공학회 2014 Environmental Engineering Research Vol.19 No.1

The effects of initial solid concentration and microwave irradiation (MWI) time on the hydrolysis of waste activated sludge (WAS)were investigated. MWI time strongly influenced WAS hydrolysis for all initial solid concentrations of 8.20, 31.51, and 52.88 g VSS/L. For all WAS, the volatile suspended solids (VSS) solubilization degree ranged from 35.6% to 38.4% during a total MWI time of 10 min. Solublechemical oxygen demand (SCOD) concentration increased at a rate proportional to the decrease of VSS during the MWI. However, the clearly different VSS solubilization patterns that were observed during the MWI were explained by the 2-step hydrolysis of WAS, consisting of the initial disintegration of the easily degradable part of the sludge, followed by the subsequent disintegration of the hardlydegradable part of the sludge. WAS hydrolysis rates for 3 to 6 min of MWI were significantly lower than those for less than 3 min, or more than 6 min. From these results, 3 min MWI time and WAS of 31.51 g VSS/L (centrifugal thickener WAS) showed the most efficienthydrolysis of WAS at 36.0%. The profiles of total nitrogen (T-N) concentrations corresponded well to the SCOD increases in terms of the empirical formula of bacterial cell mass (C5H7O₂N). The negligible T-N increase and pH decrease during WAS hydrolysis by MWI will allowthe application of this process to subsequent biological processes, such as anaerobic digestion.

허혈 유사 조건이 심방근의 활동전위 특성에 미치는 영향

김재하,주정민,조용범,신동호,안병희,주신배,김상형 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.11

저온 플라즈마 처리한 쌀국수의 품질 특성

김현주(Hyun-Joo Kim),이병원(Byong Won Lee),백기호(Ki Ho Baek),조철훈(Cheorun Jo),김재경(Jae-Kyung Kim),이진영(Jin Young Lee),이유영(Yu-Young Lee),김민영(Min Young Kim),김미향(Mi Hyang Kim),이병규(Byoungkyu Lee) 한국식품과학회 2020 한국식품과학회지 Vol.52 No.5

쌀국수의 유통 안전성 확보를 위한 기초자료를 확보하기 위하여 최근 각광받고 있는 저온 플라즈마 처리에 의한 쌀국수의 품질 특성 분석을 하였다. 본 연구에서 이용한 플라즈마는 컨테이너형 유전격벽 플라즈마로 방전 가스는 공기를 활용하여 0, 5, 10 및 20분 처리하였고 미생물 감균효과, 색도, 경도 및 지질산패도 변화를 측정하였다. 쌀국수에 B. cereus 및 E. coli O157:H7을 접종한 후 20분간 플라즈마 처리 시 E. coli O157:H7은 2.75 log CFU/g 감소하였고, B. cereus는 검출되지 않았다. 색도 측정결과 플라즈마 처리에 의해 명도(L<SUP>*</SUP>), 적색도(a<SUP>*</SUP>) 및 황색도(b<SUP>*</SUP>) 모두 증가하였으며, 경도는 처리시간이 증가함에 따라 감소하는 경향을 보였다. 하지만 플라즈마 처리에 의해 지질산화가 일어나는 경향을 보였다. 따라서 공기로 방전된 저온 플라즈마 기술은 쌀국수의 품질안전성을 개선될 것이라고 판단되나 관능적 품질 특성 개선을 위한 적합 플라즈마 모델 선정, 포장방법 개선 등의 후속연구가 필요하다고 판단된다. Cold plasma has been applied to improve quality of food product; however, studies on its effects on microbial and physicochemical qualities of rice noodles are rarely conducted. In this study, changes in the quality characteristics of rice noodles treated by cold plasma were determined. Cold plasma was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air), and dielectric barrier discharge plasma treatments were applied to rice noodle samples for 0, 10, or 20 min. Rice noodles inoculated with either Bacillus cereus or Escherichia coli O157:H7 were subjected to plasma treatment for 20 min, and the approximate bacterial count reduction were 4.10 and 2.75 log CFU/g, respectively. The Hunter color values of the sample were increased after cold plasma treatment. Peroxide values and thiobarbituric acid reactive substance (TBARS) were increased with an increase in cold plasma treatment time. Futhermore, lipid oxidation was enhanced. Although further studies are warranted to evaluate changes in chemical qualities, such as lipid oxidation of rice noodles, induced by cold plasma, the results suggest that cold plasma can improve the microbial and physical qualities of rice noodles.

Evaluation of 99mTc-MAG3-2-nitroimidazole for hypoxic tumor imaging

Yun Sang Lee,Young Joo Kim,Jae Min Jeong 대한방사성의약품학회 2019 Journal of radiopharmaceuticals and molecular prob Vol.5 No.1

2-Nitroimidazole derivatives have been reported to accumulate in hypoxic tissue. We prepared a novel 99mTc-MAG3-2-nitroimidazole and evaluated the feasibility for hypoxia imaging agent. Bz-MAG3-2-nitroimidazole wassynthesized by direct coupling of Bz-MAG3 and 2-nitroimidazole using dicyclohexylcarbodiimide. Bz-MAG3-2-nitroimidazole was labeled with 99mTc in the presence of tartaric acid and SnCl2-2H2O at 100°C for 30 min. And the reaction mixture was purified by C18 Sep-pak cartridge. The labeling efficiency and the radiochemicalpurity were checked by ITLC-SG/acetonitrile. The tumor was grown in balb/c mice for 8~13 days after thesubcutaneous injection of tumor cells, CT-26 (murine colon adenocarcinoma cell). Biodistribution study andtumor autoradiography were performed in the xenografted mice after i.v injection of 74 kBq/0.1 mL and 19MBq/0.1 mL of 99mTc-MAG3-2-nitroimidazole, respectively. In vivo images of 99mTc-MAG3-2-nitroimidazolein tumor bearing mice were obtained 1.5 hr post injection. The labeling efficiency was 45±20% and theradiochemical purity after purification was over 95%. Paper electrophoresis confirmed negative charge of99mTc-MAG3-2-nitroimidazole. 99mTc-MAG3-2-nitroimidazole was very stable at room temperature and its proteinbinding was 53%. The 99mTc-MAG3-2-nitroimidazole exhibited high uptake in the liver, stomach and intestine. In biodistribution study using tumor bearing mice, the uptakes (% ID/g) of the tumor were 0.5±0.1, 0.4±0.0,0.2±0.1 and 0.1±0.1 at 5, 15, 30 min and 4 hrs. Tumor/muscle ratio were 1.4±0.1, 2.2±0.83, 3.0±0.9, and 3.7(n=2) for 5, 15, 30 min and 4 hrs. The uptake in hypoxic area was found higher than in non-hypoxic area oftumor tissue by autoradiography. In vivo images showed the relatively faint uptake to the hypoxic tumor region. 99mTc-MAG3-2-nitroimidazole was successfully synthesized and found feasible for imaging hypoxia

Slide Session : OS-111 ; Sleep : The Effects of Dexmedetomidine for Sleep in Critically Ill Patients: Pilot Study

( Se Joong Kim ),( Jinsoo Min ),( Jisoo Park ),( Yeon Joo Lee ),( Jong Sun Park ),( Ho Il Yoon ),( Jae Ho Lee ),( Choon Taek Lee ),( Young Jae Cho ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Many critically ill patients in the intensive care unit (ICU) experience sleep disruption and delirium. For the sedation of these patients, dexmedetomidine is one of commonly recommended sedatives because of its pharmacokinetic merit. This pilot study was undertaken to identify the effects of dexmedetomidine for sleep and delirium in critically ill patients. Methods: This prospective study was conducted in medical ICU of a tertiary referral hospital. Dexmedetomidine was administered with the maintenance dose of 0.4-0.7μg/ kg/hr and adjusted by Richmond Agitation Sedation Scale score of 0 to -2. Portable polysomnography was performed in the ICU over 24 hour to assess the quantity and quality of sleep. The confusion assessment method for ICU was used for detection of delirium. Results: Total 9 patients were enrolled. Median age was 77.0 (Range: 61-90) and 3 patients experienced delirium. Median total sleep time was 283 (IQR: 56-739) min. The majority of sleep was stage 1 (median 208 [IQR: 56-356] min) and 2 (median 75 [IQR: 7-396] min) with absent REM and stage 3 sleep. The dose of dexmedetomidine was not associated with total sleep time, stage 1 and stage 2 sleep (all P>0.05). However, the patients with delirium was administered higher dose of dexmedetomidine than ones without delirium (0.67μg/kg/hr vs 0.33μg/kg/hr, P=0.006). Conclusions: Although proper sedation was met with dexmedetomidine, the quantity and quality of sleep in critically ill patients were poor. Further study is required for the promotion of good sleep and the prevention of delirium in ICU patients.

Free Paper Presentation : OS-111 ; The Effects of Dexmedetomidine for Sleep in Critically Ill Patients: Pilot Study

( Se Joong Kim ),( Jin Soo Min ),( Ji Soo Park ),( Yeon Joo Lee ),( Jong Sun Park ),( Ho Il Yoon ),( Jae Ho Lee ),( Choon Taek Lee ),( Young Jae Cho ) 대한결핵 및 호흡기학회 2014 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.118 No.-

Background: Many critically ill patients in the intensive care unit (ICU) experience sleep disruption and delirium. For the sedation of these patients, dexmedetomidine is one of commonly recommended sedatives because of its pharmacokinetic merit. This pilot study was undertaken to identify the effects of dexmedetomidine for sleep and delirium in critically ill patients. Methods: This prospective study was conducted in medical ICU of a tertiary referral hospital. Dexmedetomidine was administered with the maintenance dose of 0.4-0.7μg/kg/hr and adjusted by Richmond Agitation Sedation Scale score of 0 to -2. Portable polysomnography was performed in the ICU over 24 hour to assess the quantity and quality of sleep. The confusion assessment method for ICU was used for detection of delirium. Results: Total 9 patients were enrolled. Median age was 77.0 (Range: 61-90) and 3 patients experienced delirium. Median total sleep time was 283 (IQR: 56-739) min. The majority of sleep was stage 1 (median 208 [IQR: 56-356] min) and 2 (median 75 [IQR: 7-396] min) with absent REM and stage 3 sleep. The dose of dexmedetomidine was not associated with total sleep time, stage 1 and stage 2 sleep (all P>0.05). However, the patients with delirium was administered higher dose of dexmedetomidine than ones without delirium (0.67μg/kg/hr vs 0.33μg/kg/hr, P=0.006). Conclusions: Although proper sedation was met with dexmedetomidine, the quantity and quality of sleep in critically ill patients were poor. Further study is required for the promotion of good sleep and the prevention of delirium in ICU patients.

개의 췌도분리에서 췌장의 팽창과 콜라겐 분해요소

이상훈,김성주,박정환,김종성,오승훈,한진수,정인경,양태영,김동준,김광원,이문규,민용기,이명식,정재훈,함종렬 대한당뇨병학회 2000 Diabetes and Metabolism Journal Vol.24 No.2

Backgrounds: One of the main problems conditioning the outcome of islet transplantation is the ability to separate a sufficient number of viable islets with preserved function. Islet purification is critically affected by all of the isolation stages. Thus, it is necessary to set up the standard isolation method that islets are separate well from acinar without compromising islet yield and viability. Methods: Twenty three adult mongrel dogs were used for the experiment of total pancreatectomy with islet isolation. The islets were properly isolated by a modified Recordi method. The obtained islets were further purified by centrifugation on discontinuous gradients using cell separation system (Model 2991, Cobe, Lakewood Colo). We evaluated islet number (islet equivalent number, 150 um equivalents/kg of recipient body weight, IEq/kg), purity, cell volume, viabilty, recovery rate, and comparison of outcome according to the isolation conditions. Results: 1) The mean of islet numbers before purification were 13543±9431Eq/kg, digestion times were 13.8±2.6 min., digestion temperature was 37.4±0.2℃, purity was 59.7?.0%, viability was 90.0±2.1%, cell volume was 4.7±1.1 mL, islet number after purification were 4064±361 IEq/kg, and recovery rate was 29±2.9%. 2) Isolated islet numbers were different according to the degree of pancreas distension with collagenase, digestion temperature, and digestion time. 3) The best conditions for islet isolation were above 37.5℃ in temperature at recirculation of collagenase, within 12 min in digestion time and well distended pancreas with collagenase. 4) According to multiple regression adjusted by variable factors, the degree of pancreas distension with collagenase and digestion time were independently associated factors for successful islet isolation. Conclusions: In this study, we concluded that the degree of pancreas distension with collagenase and digestion time were independent factors for successful islet isolation and the best conditions for islet isolation were above 37.5℃ in temperature at recirculation of collagenase, within 12 min in digestion time and well distended pancreas with collagenase.

Evaluation of ^99mTc-MAG₃-2-nitroimidazole for hypoxic tumor imaging

Lee, Yun-Sang,Kim, Young Joo,Jeong, Jae Min Korean Society of Radiopharmaceuticals and Molecul 2019 Journal of radiopharmaceuticals and molecular prob Vol.5 No.1

2-Nitroimidazole derivatives have been reported to accumulate in hypoxic tissue. We prepared a novel $^{99m}Tc-MAG_3$-2-nitroimidazole and evaluated the feasibility for hypoxia imaging agent. $Bz-MAG_3$-2-nitroimidazole was synthesized by direct coupling of $Bz-MAG_3$ and 2-nitroimidazole using dicyclohexylcarbodiimide. $Bz-MAG_3$-2-nitroimidazole was labeled with $^{99m}Tc$ in the presence of tartaric acid and $SnCl_2-2H_2O$ at $100^{\circ}C$ for 30 min. And the reaction mixture was purified by $C_{18}$ Sep-pak cartridge. The labeling efficiency and the radiochemical purity were checked by ITLC-SG/acetonitrile. The tumor was grown in balb/c mice for 8~13 days after the subcutaneous injection of tumor cells, CT-26 (murine colon adenocarcinoma cell). Biodistribution study and tumor autoradiography were performed in the xenografted mice after i.v injection of 74 kBq/0.1 mL and 19 MBq/0.1 mL of $^{99m}Tc-MAG_3$-2-nitroimidazole, respectively. In vivo images of $^{99m}Tc-MAG_3$-2-nitroimidazole in tumor bearing mice were obtained 1.5 hr post injection. The labeling efficiency was $45{\pm}20%$ and the radiochemical purity after purification was over 95%. Paper electrophoresis confirmed negative charge of $^{99m}Tc-MAG_3$-2-nitroimidazole. $^{99m}Tc-MAG_3$-2-nitroimidazole was very stable at room temperature and its protein binding was 53%. The $^{99m}Tc-MAG_3$-2-nitroimidazole exhibited high uptake in the liver, stomach and intestine. In biodistribution study using tumor bearing mice, the uptakes (% ID/g) of the tumor were $0.5{\pm}0.1$, $0.4{\pm}0.0$, $0.2{\pm}0.1$ and $0.1{\pm}0.1$ at 5, 15, 30 min and 4 hrs. Tumor/muscle ratio were $1.4{\pm}0.1$, $2.2{\pm}0.83$, $3.0{\pm}0.9$, and 3.7 (n=2) for 5, 15, 30 min and 4 hrs. The uptake in hypoxic area was found higher than in non-hypoxic area of tumor tissue by autoradiography. In vivo images showed the relatively faint uptake to the hypoxic tumor region. $^{99m}Tc-MAG_3$-2-nitroimidazole was successfully synthesized and found feasible for imaging hypoxia.

Biodistribution and PET imaging of [¹⁸F]FMISO in mousecolon cancer xenografted mice

Seelam, Sudhakara Reddy,Lee, Ji Youn,Kim, Young Joo,Lee, Yun-Sang,Jeong, Jae Min Korean Society of Radiopharmaceuticals and Molecul 2015 Journal of radiopharmaceuticals and molecular prob Vol.1 No.2

Hypoxia is an important adverse prognostic factor for tumor progression and is a major cause of failure of radiation therapy. In case of short-term hypoxia, the metabolism can recover to normal, but if hypoxia persists, it causes irreversible cell damage and finally leads to death. So a hypoxia marker would be very useful in oncology. In particular, 2-nitroimidazole can be reduced to form a reactive chemical species, which can bind irreversibly to cell components in the absence of sufficient oxygen, thus, the development of radiolabeled nitroimidazole derivatives for the imaging of hypoxia remains an active field of research to improve cancer therapy result. 2-nitroimidazole based hypoxia marker, [$^{18}F$]FMISO holds promise for the evaluation of tumor hypoxia by Positron emission tomography (PET), at both global and local levels. In the present study, [$^{18}F$]FMISO was synthesized using an automatic synthesis module with high radiochemical purity (>99%) in 60 min. Immunohistochemical analysis using pimonidazole confirmed the presence of hypoxia in xenografted CT-26 tumor tissue. A biodistribution study in CT-26 xenografted mice showed that the increased tumor-to-muscle ratio and tumor-to-blood ratios from 10 to 120 min post-injection. In the PET study, [$^{18}F$]FMISO also showed increased tumor-to-muscle ratios from 10 to 120 min post-injection. In conclusion, this study demonstrates the feasibility and utility of [$^{18}F$]FMISO for imaging hypoxiain mouse colon cancer model using small animal PET.

다제내성 그람양성균에 대한 Linezolid(Zyvox^(�))의 시험관내 항균력 비교

박대원,정희진,엄중식,황병연,김성범,이재갑,이연주,정혜원,정성주,박재형,이진수,손장욱,김우주,김민자,박승철 대한감염학회 2003 감염과 화학요법 Vol.35 No.5

배경 : MRSA, VRE, VRSA같은 다제 내성 그람 양성균의 등장에 따라 glycopeptide를 대체할 새로운 항생제의 개발이 필요하게 되었고 결과적으로 새로운 항생제인 linezolid라는 항생제가 개발되었다. Linezolid는 이전의 항생제와는 다른 새로운 계열의 oxazolidinone으로 경구 이용률이 우수하다. 원내 및 원외감염의 중요한 원인균이 되고 있는 MRSA, VRE에 대한 적절한 경구용 항균제가 없는 국내에서 폐렴 및 피부 연조직 감염에서 경구용으로 사용해 볼 수 있는 약제이다. 본 연구에서는 고대 구로 병원에서 분리된 MRSA, VRE 등을 대상으로 다른 여러 항균제와 비교한 linezolid의 시험관내 항균력을 조사하고자 하였다. 재료 및 방법 : 연구대상은 1998년 1월부터 2000년 12월까지 본원에서 입원 및 외래를 통하여 피부 연조직 감염증 및 호흡기 감염증, 요로감염증으로 진단된 환자들의 가검물로부터 분리된 MRSA 60균주, VRE 43균주, PRSP 25균주를 액체배지 또는 한천배지 희석법을 통하여 linezolid 및 기타 항균제에 대한 최소발육억제농도를 구하였다. 결과 : 실험에 사용한 S. aureus는 모두 MRSA였고 이들은 linezolid에 대해 MIC_(90) 2㎍/㎖(MIC 범위 1-2㎍/㎖), Enterococcus spp는 모두 VRE로 linezolid의 MIC_(90)은 2㎍/㎖로 MIC 범위는 1-4㎍/㎖였다. 한 개의 균주에서 MIC 4㎍/㎖로 중등도 감수성을 보였으나 MIC breakpoint가 (8㎍/㎖인 내성균주는 없고 모두 감수성을 보였다. S. pneumoniae의 경우 penicillin 내성이었고, linezolid MIC_(90) 1㎍/㎖ (MIC 범위 0.5-1㎍/㎖)로 전부 감수성을 보였다. 결론 : Linezolid는 MRSA를 위시한 VRE, PRSP 등의 다제 내성 그람 양성균에 대하여 우수한 시험관내 항균력을 보임을 알 수 있었다. Background : The emergence of multi-drug resistant Gram-positive cocci, such as MRSA, VRE, and VRSA, necessitated to develop new antibiotics, which could replace the glycopeptide. As a result, a new antibiotics named linezolid was developed. Linezolid is different line of oxazolidinones with a good oral bioavailability, compared to other antibiotics. Since appropriate oral antibiotics are not presently available for MRSA, which is a major cause of nosocomial and community acquired infections, the introduction of linezolid will have favorable effect on treatment of infections such as pneumonia or skin infections. In this study, we investigated the antibiotic effect of linezolid on MRSA and VRE isolated from patients who were treated in Korea University Guro Hospital. Material and Methods : By using broth microdilution and agar dilution method we measured minimum inhibitory concentration (MIC) with sixty S. aureus, forty three Enterococcus spp., and twenty five S. pneumoniae isolates from patients who were diagnosed as skin, soft tissue, respiratory, and urinary infections in Korea University Guro Hospital from January, 1998 to December, 2002. Results : All of S. aureus used in this study were MRSA, and MIG_(90) of linezolid was below 2 ㎍/㎖ (MIC ranged between 1-2 ㎍/㎖). All of Enterococcus spp. were VRE, and had MIG_(90) of 2 ㎍/㎖ (MIC ranged between 1 to 4 ㎍/㎖). One of the VRE showed intermediate susceptibility with MIC of 4 ㎍/㎖. However, none was resistant with MIC breakpoint above 8 ㎍/㎖. All of S. pneumoniae were resistant to penicillin, but they were susceptible to linezolid with MICao of 1 ㎍/㎖(MIC range 0.5-1㎍/㎖). Conclusion : In conclusions, linezolid has an excellent in vitro antibiotic effect on multi-drug resistant Gram-positive cocci, such as MRSA, PRSP, and VRE.