• Title/Summary/Keyword: 반감기

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Behavior of benzoylurea insecticide teflubenzuron and flucycloxuron in soil environment (Benzoylurea계 살충제 teflubenzuron과 flucycloxuron의 토양환경중 동태)

  • Kim, Tae-Hwa;Kim, Jang-Eok
    • Applied Biological Chemistry
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    • v.36 no.6
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    • pp.510-516
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    • 1993
  • The degradation and leaching pattern of benzoylurea insecticide teflubenzuron and flucycloxuron in soil environment and their effect on urease activity were investigated. The half-life of teflubenzuron was 39.1 days and 20.9 days in Chilgok and Ansim soil of nonsterilized condition, respectively, and that of flucycloxuron was 102.3 days and 50.1 days. Teflubenzuron and flucycloxuron were degraded more rapidly in Ansim soil with rich organic matter than Chilgok soil, and were degraded very slowly under sterilized condition. Their degradation seemed to be mainly mediated by microorganisms in soil. Teflubenzuron was degraded 63.2 days and 29.2 days faster than flucycloxuron under nonsterilized condition of Chilgok and Ansim soil. The inhibition of urease by the pesticides in two kinds of soil was strongly affected $(37.6{\sim}42.4%)$ in the early stage of their treatment but hardly affected or increased a little after 120 days. The teflubenzuron and flucycloxuron remained in the upper 5 cm of the soil column after elution with 1,000 ml of water, and they were not detected in leachate.

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The Emergence of Kim, Jung-Eun in North Korea and a Prospect for Its Political Ideological Education System (북한의 김정은 등장과 정치사상 교육의 향후 전망)

  • Park, Chan-Seok
    • Journal of Ethics
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    • no.82
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    • pp.53-72
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    • 2011
  • The North Korea have supported their own political ideological education system to maintain their basic framework of society. The north korean political education contents become from now on it be done harder. That answer is up to the government of the North Korea, and the general public in North Korea would be going after it. However, when we review this closely, both positions of the North Korean government and the general public would be different each other as before. I would figure out whether the political ideological education system in North Korea would be going on with making realistic changes or just maintaining their old system. The political and ideological education might make settled flexibility. On the other hand, we can expect that it could be reinforced by the North Korean government. For this content, this research is going to try to understand the characteristics of North Korea's ideological education policy considering both position of the North Korean government and the general public thoroughly.

Pharmacokinetic Study of Isoniazid and Rifampicin in Healthy Korean Volunteers (정상 한국인에서의 Isoniazid와 Rifampicin 약동학 연구)

  • Chung, Man-Pyo;Kim, Ho-Cheol;Suh, Gee-Young;Park, Jeong-Woong;Kim, Ho-Joong;Kwon, O-Jung;Rhee, Chong-H.;Han, Yong-Chol;Park, Hyo-Jung;Kim, Myoung-Min;Choi, Kyung-Eob
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.3
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    • pp.479-492
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    • 1997
  • Background : Isoniazid(INH) and rifampicin(RFP) are potent antituberculous drugs which have made tuberculous disease become decreasing. In Korea, prescribed doses of INH and RFP have been different from those recommended by American Thoracic Society. In fact they were determined by clinical experience rather than by scientific basis. Even there has been. few reports about pharmacokintic parameters of INH and RFP in healthy Koreans. Method : Oral pharmacokinetics of INH were studied in 22 healthy native Koreans after administration of 300 mg and 400mg of INH to each same person successively at least 2 weeks apart. After an overnight fast, subjects received medication and blood samples were drawn at scheduled times over a 24-hour period. Urine collection was also done for 24 hours. Pharmacokinetics of RFP were studied in 20 subjects in a same fashion with 450mg and 600mg of RFP. Plasma and urinary concentrations of INH and RFP were determined by high-performance liquid chromatography(HPLC). Results : Time to reach peak serum concentration (Tmax) of INH was $1.05{\pm}0.34\;hrs$ at 300mg dose and $0.98{\pm}0.59\;hrs$ at 400mg dose. Half-life was $2.49{\pm}0.88\;hrs$ and $2.80{\pm}0.75\;hrs$, respectively. They were not different significantly(p > 0.05). Peak serum concentration(Cmax) after administration of 400mg of INH was $7.14{\pm}1.95mcg/mL$ which was significantly higher than Cmax ($4.37{\pm}1.28mcg/mL$) by 300mg of INH(p < 0.01). Total clearance(CLtot) of INH at 300mg dose was $26.76{\pm}11.80mL/hr$. At 400mg dose it was $21.09{\pm}8.31mL/hr$ which was significantly lower(p < 0.01) than by 300mg dose. While renal clearance(CLr) was not different among two groups, nonrenal clearance(CLnr) at 400mg dose ($18.18{\pm}8.36mL/hr$) was significantly lower than CLnr ($23.71{\pm}11.52mL/hr$) by 300mg dose(p < 0.01). Tmax of RFP was $1.11{\pm}0.41\;hrs$ at 450mg dose and $1.15{\pm}0.43\;hrs$ at 600mg dose. Half-life was $4.20{\pm}0.73\;hrs$ and $4.95{\pm}2.25\;hrs$, respectively. They were not different significantly(p > 0.05). Cmax after administration of 600mg of RFP was $13.61{\pm}3.43mcg/mL$ which was significantly higher than Cmax($10.12{\pm}2.25mcg/mL$) by 450mg of RFP(p < 0.01). CLtot of RFP at 450mg dose was $7.60{\pm}1.34mL/hr$. At 600mg dose it was $7.05{\pm}1.20mL/hr$ which was significantly lower(p < 0.05) than by 450mg dose. While CLr was not different among two groups, CLnr at 600 mg dose($5.36{\pm}1.20mL/hr$) was significantly lower than CLnr($6.19{\pm}1.56mL/hr$) by 450mg dose(p < 0.01). Conclusion : Considering Cmax and CLnr, 300mg, of INH and 450mg RFP might be sufficient doses for the treatment of tuberculosis in Koreans. But it remains to be clarified in the patients with tuberculosis.

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In the Treatment I-131, the Significance of the Research that the Patient's Discharge Dose and Treatment Ward can Affect a Patient's Kidney Function on the Significance of Various Factors (I-131 치료시 환자의 신장기능과 다양한 요인으로 의한 퇴원선량 및 치료병실 오염도의 유의성에 관한 연구)

  • Im, Kwang Seok;Choi, Hak Gi;Lee, Gi Hyun
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.1
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    • pp.62-66
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    • 2013
  • Purpose: I-131 is a radioisotope widely used for thyroid gland treatments. The physical half life is 8.01 and characterized by emitting beta and gamma rays which is used in clinical practice for the purpose of acquiring treatment and images. In order to reduce the recurrence rate after surgery in high-risk thyroid cancer patients, the remaining thyroid tissue is either removed or the I-131 is used for treatment during relapse. In cases of using a high dosage of radioactive iodine requiring hospitalization, the patient is administered dosage in the hospital isolation ward over a certain period of time preventing I-131 exposure to others. By checking the radiation amount emitted from patients before discharge, the patients are discharged after checking whether they meet the legal standards (50 uSv/h). After patients are discharged from the hospital, the contamination level is checked in many parts of the ward before the next patients are hospitalized and when necessary, decontamination operations are performed. It is expected that there is exposure to radiation when measuring the ward contamination level and dose check emitted from patients at the time of discharge whereby the radiation exposure by health workers that come from the patients in this process is the main factor. This study analyzed the correlation between discharge dose of patients and ward contamination level through a variety of factors such as renal functions, gender, age, dosage, etc.). Materials and Method: The study was conducted on 151 patients who received high-dosage radioactive iodine treatment at Soon Chun Hyang University Hospital during the period between 8/1/2011~5/31/2012 (Male: Female: 31:120, $47.5{\pm}11.9$, average dosage of $138{\pm}22.4$ mCi). As various factors expected to influence the patient discharge dose & ward contamination such as the beds, floors, bathroom floors, and washbasins, the patient renal function (GFR), age, gender, dosage, and the correlation between the expected Tg & Tg-Tb expected to reflect the remaining tissue in patients were analyzed. Results: In terms of the discharge dose and GFR, a low correlation was shown in the patient discharge dose as the GFR was higher (p < 0.0001). When comparing the group with a dosage of over 150mCi and the group with a lower dosage, the lower dosage group showed a significantly lower discharge dose ($24{\pm}10.4uSv/h$ vs $28.7{\pm}11.8uSv/h$, p<0.05). Age, gender, Tg, Tg-Tb did not show a significant relationship with discharge dose (p> 0.05). The contamination level in each spot of the treatment ward showed no significant relationship with GFR, Tg, Tg-Tb, age, gender, and dosage (p>0.05 ). Conclusion: This study says that discharge of the dose in the patient's body is low in GFR higher and Dosage 150mCi under lower. There was no case of contamination of the treatment ward, depending on the dose and renal association. This suggests that patients' lifestyles or be affected by a variety of other factors.

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Removal Characteristics of Residual Hydrogen Peroxide (H2O2) according to Application of Peroxone Process in O3/BAC Process (O3/BAC 공정에서 Peroxone 공정 적용에 따른 잔류 과산화수소 제거 특성)

  • Yeom, Hoon-Sik;Son, Hee-Jong;Seo, Chang-Dong;Kim, Sang-Goo;Ryu, Dong-Choon
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.12
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    • pp.889-896
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    • 2013
  • Advanced Oxidation Processes (AOP) have been interested for removing micropollutants in water. Most of water treatment plants (WTPs) located along the lower part of Nakdong River have adopted the $O_3/BAC$ process and have interesting in peroxone process a kind of AOP. This study evaluated the removal characteristics of residual hydrogen peroxide ($H_2O_2$) combining with the biofiltration process in the next BAC process when the hydrogen peroxide is applied for the WTP operating $O_3/BAC$ process. In the experiment, changing the temperature and the concentration of $H_2O_2$ of influent, the biofiltration process showed rapidly dropped the biodegradability when the $H_2O_2$ concentration was increased and lowered water temperature while BAC process maintained relatively stable efficiency. The influent fixed at $20^{\circ}C$ and the concentration of $H_2O_2$ at 300 mg/L was continuously input for 78 hours. Most of the $H_2O_2$ in the influent did not remove at the biofiltration process controlled 5 to 15 minutes EBCT condition after 24~71 hours operating time while BAC process controlled 5 to 15 minutes EBCT showed 38~91% removal efficiency condition after 78 hours operating time. Besides, after 78 hours continuously input experiment, the biomass and activity of attached bacterial on the biofilter and BAC were $6.0{\times}10^4CFU/g$, $0.54mg{\cdot}C/m^3{\cdot}hr$ and $0.4{\times}10^8CFU/g$, $1.42mg{\cdot}C/m^3{\cdot}hr$ respectively. These biomass and activity values were decreased 99% and 72% in biofilter and 68% and 53% in BAC compared with initial condition. The biodegradation rate constant ($k_{bio}$) and half-life ($t_{1/2}$) in BAC were decreased from $1.173min^{-1}$ to $0.183min^{-1}$ and 0.591 min to 3.787 min respectively according to increasing the $H_2O_2$ concentration from 10 mg/L to 300 mg/L at $5^{\circ}C$ water temperature and the $k_{bio}$ and $t_{1/2}$ were $1.510min^{-1}$ to $0.498min^{-1}$ and 0.459 min to 1.392 min at $25^{\circ}C$ water temperature. By increasing the water temperature from $5^{\circ}C$ to $15^{\circ}C$ or $25^{\circ}C$, the $k_{bio}$ were increased 1.1~2.1 times and 1.3~4.4 times. If a water treatment plant operating $O_3/BAC$ process is considering the hydrogen peroxide for the peroxone process, post BAC could effectively decrease the residual $H_2O_2$, moreover, in case of spilling the $H_2O_2$ into the water process line, these spilled $H_2O_2$ concentration can be able to decrease by increasing the EBCT at the BAC process.

The Evaluation of IL-8 in the Serum of Pneumoconiotic patients (진폐증 환자에서의 혈청내 IL-8 농도)

  • Ahn, Hyeong Sook;Kim, Ji Hong;Chang, Hwang Sin;Kim, Kyung Ah;Lim, Young
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.6
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    • pp.945-953
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    • 1996
  • Background : Many acute and chronic lung diseases including pneumoconiosis are characterized by the presence of increased numbers of activated macrophages. These macrophages generate several inflammatory cell chemoattractants, by which neutrophil migrate from vascular compartment to the alveolar space. Recruited neutrophils secrete toxic oxygen radicals or proteolytic enzymes and induce inflammatory response. Continuing inflammatory response results in alteration of the pulmonary structure and irreversible fibrosis. Recently, a polypeptide with specific neutrophil chemotactic activity, interleukin-8(IL-8), has been cloned and isolated from a number of cells including : monocytes, macrophages and fibroblasts. IL-1 and/or TNF-${\alpha}$ preceded for the synthesis of IL-8, and we already observed high level of IL-1 and TNF-${\alpha}$ in the pneumoconioses. So we hypothesized that IL-8 may be a central role in the pathogenesis of pneumoconiosis. In order to evaluate the clinical utility of IL-8 as a biomarker in the early diagnosis of pneumoconiosis, we investigated the increase of IL-8 in the pneumoconiotic patient and the correlation between IL-8 level and progression of pneumoconiosis. Method : We measured IL-8 in the serum of 48 patients with pneumoconiosis and 16 persons without dust exposure history as a control group. Pneumoconiotic cases were divided into 3 groups according to ILO Classification : suspicious group(n=16), small opacity group(n=16) and large opacity group(n=16). IL-8 was measured by a sandwich enzytne immunoassay technique. All data were expressed as the $mean{\pm}standard$ deviation. Results: 1) The mean value of age was higher in the small opacity and large opacity group than comparison group, but smoking history was even. Duration of dust exposure was not different among 3 pneumoconiosis groups. 2) IL-8 level was $70.50{\pm}53.63pg/m{\ell}$ in the suspicious group, $107.50{\pm}45.88pg/m{\ell}$ in the small opacity group, $132.50{\pm}73.47pg/m{\ell}$ in the large opacity group and $17.85{\pm}33.85pg/m{\ell}$ in the comparison group. IL-8 concentration in all pneumoconiosis group was significant higher than that in the comparison group(p<0.001). 3) IL-8 level tended to increase with the progression of pneumoconiosis. Multiple comparison test using Anova/Scheffe analysis showed a significant difference between suspicious group and large opacity group(p<0.05). 4) The level of IL-8 was correlated with the progression of pneumoconiosis(r=0.4199, p<0.05). Conclusion : IL-8 is thought to be a good biomarker for the early diagnosis of pneumoconiosis.

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Radiation Absorbed Dose Calculation Using Planar Images after Ho-166-CHICO Therapy (Ho-166-CHICO 치료 후 평면 영상을 이용한 방사선 흡수선량의 계산)

  • 조철우;박찬희;원재환;왕희정;김영미;박경배;이병기
    • Progress in Medical Physics
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    • v.9 no.3
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    • pp.155-162
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    • 1998
  • Ho-l66 was produced by neutron reaction in a reactor at the Korea Atomic Energy Institute (Taejon, Korea). Ho-l66 emits a high energy beta particles with a maximum energy of 1.85 MeV and small proportion of gamma rays (80 keV). Therefore, the radiation absorbed dose estimation could be based on the in-vivo quantification of the activity in tumors from the gamma camera images. Approximately 1 mCi of Ho-l66 in solution was mixed into the flood phantom and planar scintigraphic images were acquired with and without patient interposed between the phantom and scintillation camera. Transmission factor over an area of interest was calculated from the ratio of counts in selected regions of the two images described above. A dual-head gamma camera(Multispect2, Siemens, Hoffman Estates, IL, USA) equipped with medium energy collimators was utilized for imaging(80 keV${\pm}$10%). Fifty-nine year old female patient with hepatoma was enrolled into the therapeutic protocol after the informed consent obtained. Thirty millicuries(110MBq) of Ho-166-CHICO was injected into the right hepatic arterial branch supplying hepatoma. When the injection was completed, anterior and posterior scintigraphic views of the chest and pelvic regions were obtained for 3 successive days. Regions of interest (ROIs) were drawn over the organs in both the anterior and posterior views. The activity in those ROIs was estimated from geometric mean, calibration factor and transmission factors. Absorbed dose was calculated using the Marinelli formula and Medical Internal Radiation Dose (MIRD) schema. Tumor dose of the patient treated with 1110 MBq(30 mCi) Ho-l66 was calculated to be 179.7 Gy. Dose distribution to normal liver, spleen, lung and bone was 9.1, 10.3, 3.9, 5.0 % of the tumor dose respectively. In conclusion, tumor dose and absorbed dose to surrounding structures were calculated by daily external imaging after the Ho-l66 therapy for hepatoma. In order to limit the thresholding dose to each surrounding organ, absorbed dose calculation provides useful information.

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Disappearance of Organic Phosphate Insecticides Residue on Vegetables and Fruit Crops (과실 및 채소류에 대한 유기 인계 농약의 잔류소장)

  • Woo, Ki-dae
    • Korean Journal of Agricultural Science
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    • v.4 no.2
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    • pp.229-238
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    • 1977
  • Sumithion and EPN residues on grapes, EPN and Diazinon on chinese cabbage, Parathion on peaches, Dimethoate on tomatoes, and EPN and Malathion on cucumber were analyzed in terms of 0, 3, 7, 14, 21 and 30 days after last application for the pesticides safty use. From the disappearance rate for various organo-phosphate insecticides on vegetables and fruit crops, following results are obtained. 1. On Chinese cabbage, Diazinon residues were 0.25~0.38p.p.m three weeks after one application, and EPN were 1.39~2.69p.p.m seven days after one application and 0.96~2.34p.p.m two weeks after twice application. 2. EPN residues on grapes were 1.09~1.80p.p.m seven days after one application and Sumithion were 0.17~0.53p.p.m fourteen days after one application. 3. On peaches, Parathion residues were 0.40~0.61p.p.m two weeks after last application. 4. Dimethoate residues on tomatoes were 0.141p.p.m seven days after four times application. 5. On cucumber, EPN residues were 2.11~2.14p.p.m three days after twice application, and Malathion were 0.46p.p.m 3 day after four times application but 0.062~0.025p.p.m three days after last application. 6. Rate of degradation of organo-phosphate chemicals is inversely related to half-life of its. 7. Minimum intervals between last treatment and harvest to prevent unsafty residues are as follows. 7 days for EPN with one application and 14 days with twice application on chinese cabbage, 3 days on cucumber and 7 days on grape, 14 days for parathion, 7 days for dimethoate on tomatoes, 0 to 3 days for Malathion on cucumber, 21 days for Sumithion on grape, 21 days on chinese cabbage for Diazinon.

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Adhesion-induced generation of oxygen free radical from human alveolar macrophages and its mechanisms (폐포대식세포의 부착에 의한 산소유리기 분비능 활성화 및 그 기전)

  • Chung, Man-Pyo;Yoo, Chul-Gyu;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.2
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    • pp.210-220
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    • 1996
  • Background : Neutrophils or monocytes separated in vitro by the adherence to plastic surface are known to be activated by surface adherence itself and subsequent experimental data might be altered by surface adherence. In the process of surface adherence, adhesion molecules have a clear role in intracellular signal pathway of cellular activation. Human alveolar macrophages(HAM) are frequently purified by the adherence procedure after bronchoalveolar lavage. But the experimental data of many reports about alveolar macrophages have ignored the possibility of adhesion-induced cellular activation. Method : Bronchoalveolar lavage was performed in the person whose lung of either side was confirmed to be normal by chest CT. With the measurement of hydrogen peroxide release from adherent HAM to plastic surface and non-adherent HAM with or without additional stimulation of phorbol myristate acetate(PMA) or N-formyl-methionyl-leucyl-phenylalanine (fMLP), we observed the effect of the adherence to plastic surface. We also evaluated the effect of various biological surfaces on adhesion-induced activation of HAM. Then, to define the intracellular pathway of signal transduction, pretreatment with cycloheximide, pertussis toxin and anti-CD11/CD18 monoclonal antibody was done and we measured hydrogen peroxide in the culture supernatant of HAM. Results : 1) The adherence itself to plastic surface directly stimulated hydrogen peroxide release from human alveolar macrophages and chemical stimuli such as phorbol myristate acetate(PMA) or N-formyl-methionyl-leucyl-phenylalanine(fMLP) colud not increase hydrogen peroxide release in these adherent macrophages which is already activated. 2) PMA activated human alveolar macrophages irrespective of the state of adhesion. However, fMLP stimulated the release of hydrogen peroxide from the adherent macrophages, but not from the non-adherent macrophages. 3) HAM adherent to A549 cell(type II alveolar epithelium-like human cell line) monolayer released more hydrogen peroxide in response to both PMA and fMLP. This adherence-dependent effect of fMLP was blocked by pretreatment of macrophages with cycloheximide, pertussis toxin and anti-CD18 monoclonal antibody, Conclusion : These results suggest that the stimulatory effect of PMA and fMLP can not be found in adherent macrophage because of the activation of human alveolar macrophage by the adherence to plastic surface and the cells adhered to biologic surface such as alveolar epithelial cells are appropriately responsive to these stimuli. It is also likely that the effect of fMLP on the adherent macrophage requires new protein synthesis via G protein pathway and is dependent on the adhesion between alveolar macrophages and alveolar epithelial cells by virtue of CD11/CD18 adhesion molecules.

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Catalases in Acinetobacter sp. Strain JC1 DSM 3803 Growing on Glucose (포도당을 이용하여 성장하는 Acinetobacter sp. Strain JC1 DSM 3809에 존재하는 Catalase)

  • Shin, Kyoung-Ju;Ro, Young-Tae;Kim, Young-Min
    • Korean Journal of Microbiology
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    • v.32 no.2
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    • pp.155-162
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    • 1994
  • Cells of Acinetobacter sp. strain JC1 DSM 3803, an aerobic monoxide-oxidizing bacterium, growing on glucose exhibited high catalase activity at the mid-exponential growth phase. The enzyme activity decreased gradually after then until the early stationary phase, increased again at the mid-stationary phase, and then decreased again thereafter. Cells growing on glucose was found to contain three kinds of catalses. Cat1, Cat2 and Cat3. The activities of Cat1 and Cat3 did change significantly during growth, but that of Cat2 exhibited significant variation. Cat3 was found to present only in cells growing on glucose, but not in cells growing on carbon monoxide of methanol. The activities of call and Cat3 in cell-free extracts were stable upon treatment with ethanol and chloroform, but decreased to some extent when the enzymewere treated with 2mM $H_2O_2$ and/or 3-amino-1,2,4-triazole (AT). Cat2 was found to be extremely sensitive to the ethanol-chloroform and $H_2O_2$ treatments, but was insensitive to the AT treatment. Cat1 exhibited enzyme activity after incubation for 1 min at 80$^{\circ}C$. Cat2 and Cat3 did not show enzyme activity after incubation for 1 min at 60$^{\circ}C$ and 70$^{\circ}C$, respectively. Cat2 was found to have peroxidase activity. Cat3 was purified to homogenity in seven steps. The molecular weight of the native enzyme was estimated to be 150,000. Sodium dodecyl sulfate-gel electrophoresis revealed two identical subunits of molecular weight 65,000. The enzyme was found to show two $K_m$ values of 39 mM and 58mM. The optimal pH for the enzyme activity was 7.0, but the activities at pH 6.0, 8.0, and 9.0, were found to be comparable to that at the optimal pH. The optimal temperature for the enzyme activity was found to be 40$^{\circ}C$. The enzyme also exhibited strong activity at 20$^{\circ}C$, 30$^{\circ}C$, and 50$^{\circ}C$. The purified enzyme was not affected by the ethanol-chloroform treatment. The enzyme, howerver, showed less than 10% of the original activity when it was treated with 12 mN AT, 0.1 mM $NaN_3$ of 1mM KCN.

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