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A Statistical model to Predict soil Temperature by Combining the Yearly Oscillation Fourier Expansion and Meteorological Factors (연주기(年週期) Fourier 함수(函數)와 기상요소(氣象要素)에 의(依)한 지온예측(地溫豫測) 통계(統計) 모형(模型))

  • Jung, Yeong-Sang;Lee, Byun-Woo;Kim, Byung-Chang;Lee, Yang-Soo;Um, Ki-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.23 no.2
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    • pp.87-93
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    • 1990
  • A statistical model to predict soil temperature from the ambient meteorological factors including mean, maximum and minimum air temperatures, precipitation, wind speed and snow depth combined with Fourier time series expansion was developed with the data measured at the Suwon Meteorolical Service from 1979 to 1988. The stepwise elimination technique was used for statistical analysis. For the yearly oscillation model for soil temperature with 8 terms of Fourier expansion, the mean square error was decreased with soil depth showing 2.30 for the surface temperature, and 1.34-0.42 for 5 to 500-cm soil temperatures. The $r^2$ ranged from 0.913 to 0.988. The number of lag days of air temperature by remainder analysis was 0 day for the soil surface temperature, -1 day for 5 to 30-cm soil temperature, and -2 days for 50-cm soil temperature. The number of lag days for precipitaion, snow depth and wind speed was -1 day for the 0 to 10-cm soil temperatures, and -2 to -3 days for the 30 to 50-cm soil teperatures. For the statistical soil temperature prediction model combined with the yearly oscillation terms and meteorological factors as remainder terms considering the lag days obtained above, the mean square error was 1.64 for the soil surfac temperature, and ranged 1.34-0.42 for 5 to 500cm soil temperatures. The model test with 1978 data independent to model development resulted in good agreement with $r^2$ ranged 0.976 to 0.996. The magnitudes of coeffcicients implied that the soil depth where daily meteorological variables night affect soil temperature was 30 to 50 cm. In the models, solar radiation was not included as a independent variable ; however, in a seperated analysis on relationship between the difference(${\Delta}Tmxs$) of the maximum soil temperature and the maximum air temperature and solar radiation(Rs ; $J\;m^{-2}$) under a corn canopy showed linear relationship as $${\Delta}Tmxs=0.902+1.924{\times}10^{-3}$$ Rs for leaf area index lower than 2 $${\Delta}Tmxs=0.274+8.881{\times}10^{-4}$$ Rs for leaf area index higher than 2.

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Microbiological Studies of Korean Native Soy-sauce Fermentation -A Study on the Microflora Changes during Korean Native Soy-sauce Fermentation- (한국재래식(韓國在來式) 간장의 발효미생물(醱酵微生物)에 관(關)한 연구(硏究)(제2보(第二報)) -한국재래식(韓國在來式) 간장의 담금중(中)에 있어서의 발효미생물군(醱酵微生物群)의 소장(消長)에 관(關)한 연구(硏究)-)

  • Lee, Woo-Jin;Cho, Duck-Hiyon
    • Applied Biological Chemistry
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    • v.14 no.2
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    • pp.137-148
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    • 1971
  • Studies were carried out to investigate the main fermentation microorganisms and their flora changes during Korean native soy-sauce fermentation. Korean native Maeju loaves collected from 5 Do's were separated into surface and inner parts. Four different soy-sauces-the surface part Maeju fermented soy-sauce, the inner part, the surface and inner part combined Maeju fermented soy-sauce, and the semi-Japanese type soy-sauce were fermented and the changes of fermentation microorganism flora and the various chemical components during the period of their fermentations were studied. Besides, 14 home-made soy-sauces collected from 14 different places all over Korea were examined in comparison with the laboratory soy-sauces and to determine the characteristics of Korean native soy-sauce. The results were as follows: 1. The main microorganisms in Korean native soy-sauce fermentation were determined as; Aerobic bacteria: Bacillus subtilis, Bacillus pumilus Lactic acid bacteria: Pediococcus halophilus, Leuconostoc mesenteroides Yeasts: Torulopsis datila, Saccharomyces rouxii 2. Microflora changes during Korean native soy-sauce fermentation were as follows; Aerobic bacteria increased until the 2nd week of fermentation and then gradually decreased. The lactic acid bacteria increased until the 3rd week, after which decreased. When the lactic acid fermentation lowered the pH value to below the 5.4, yeasts were able to grow and participate the fermentation. As the production of organic acids amounted, to a certain height, the growth of all microorganisms lead to the period of decline or death at about the 2nd month of fermentation. After boiling of soy-sauce most microorganisms except a few of Bacillus sp. disappeared. Occosionally yeasts and lactic acid bacteria survived depending upon the composition of soy-sauce. 3. Changes of general chemical components influencing the microflora were investigated for the period of Korean native soy-sauce fermentation. Tetal acidity, salt concentration and total nitrogen were increasing steadily over the entire period of fermentation. pH values were dropping to a certain degree of about 4.5. Salt concentration and pH value seemed to be the important factors influencing the microflora. 4. The microflora were influenced by chemical components of soy-sauce. Aerobic bacteria were able to survive in all soy-sauce as they made spores. Growth of lactic acid bacteria was inhited at 23-26% of salt concentration and pH 4.8. Soy-sauce yeasts started to grow only at pH below 5.4 and seemed to be inhibited at around 26% of salt concentration under pH 4.5-4.7. 5. The open kettle boiling of soy-sauce, the characteristic process of Korean native soy-sauce manufacturing, was effective to sterilize microorganisms, increase the salt concentration, and coagulate proteins. 6. The average viable cell counts of microorganism found in collected samples of home-made Korean native soy-sauces were; Aerobic bacteria: $53{\times}10^2\;cell/ml$ Lactic acid bacteria: 34 cell/ml Yeasts: 14 cell/ml The average values of chemical compositions of samples of home-made Korean native soy-sauce were; Salt concentration: 28.9% pH value: 4.79 Total acidity(lactic acid): 0.91g/100ml Total nitrogen: 1.09g/100ml

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The study of thermal change by chemoport in radiofrequency hyperthermia (고주파 온열치료시 케모포트의 열적 변화 연구)

  • Lee, seung hoon;Lee, sun young;Gim, yang soo;Kwak, Keun tak;Yang, myung sik;Cha, seok yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.27 no.2
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    • pp.97-106
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    • 2015
  • Purpose : This study evaluate the thermal changes caused by use of the chemoport for drug administration and blood sampling during radiofrequency hyperthermia. Materials and Methods : 20cm size of the electrode radio frequency hyperthermia (EHY-2000, Oncotherm KFT, Hungary) was used. The materials of the chemoport in our hospital from currently being used therapy are plastics, metal-containing epoxy and titanium that were made of the diameter 20 cm, height 20 cm insertion of the self-made cylindrical Agar phantom to measure the temperature. Thermoscope(TM-100, Oncotherm Kft, Hungary) and Sim4Life (Ver2.0, Zurich, Switzerland) was compared to the actual measured temperature. Each of the electrode measurement position is the central axis and the central axis side 1.5 cm, 0 cm(surface), 0.5 cm, 1.8 cm, 2.8 cm in depth was respectively measured. The measured temperature is $24.5{\sim}25.5^{\circ}C$, humidity is 30% ~ 32%. In five-minute intervals to measure the output power of 100W, 60 min. Results : In the electrode central axis 2.8 cm depth, the maximum temperature of the case with the unused of the chemoport, plastic, epoxy and titanium were respectively $39.51^{\circ}C$, $39.11^{\circ}C$, $38.81^{\circ}C$, $40.64^{\circ}C$, simulated experimental data were $42.20^{\circ}C$, $41.50^{\circ}C$, $40.70^{\circ}C$, $42.50^{\circ}C$. And in the central axis electrode side 1.5 cm depth 2.8 cm, mesured data were $39.37^{\circ}C$, $39.32^{\circ}C$, $39.20^{\circ}C$, $39.46^{\circ}C$, the simulated experimental data were $42.00^{\circ}C$, $41.80^{\circ}C$, $41.20^{\circ}C$, $42.30^{\circ}C$. Conclusion : The thermal variations were caused by radiofrequency electromagnetic field surrounding the chemoport showed lower than in the case of unused in non-conductive plastic material and epoxy material, the titanum chemoport that made of conductor materials showed a slight differences. This is due to the metal contents in the chemoport and the geometry of the chemoport. And because it uses a low radio frequency bandwidth of the used equipment. That is, although use of the chemoport in this study do not significantly affect the surrounding tissue. That is, because the thermal change is insignificant, it is suggested that the hazard of the chemoport used in this study doesn't need to be considered.

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A study on the Degradation and By-products Formation of NDMA by the Photolysis with UV: Setup of Reaction Models and Assessment of Decomposition Characteristics by the Statistical Design of Experiment (DOE) based on the Box-Behnken Technique (UV 공정을 이용한 N-Nitrosodimethylamine (NDMA) 광분해 및 부산물 생성에 관한 연구: 박스-벤켄법 실험계획법을 이용한 통계학적 분해특성평가 및 반응모델 수립)

  • Chang, Soon-Woong;Lee, Si-Jin;Cho, Il-Hyoung
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.1
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    • pp.33-46
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    • 2010
  • We investigated and estimated at the characteristics of decomposition and by-products of N-Nitrosodimethylamine (NDMA) using a design of experiment (DOE) based on the Box-Behken design in an UV process, and also the main factors (variables) with UV intensity($X_2$) (range: $1.5{\sim}4.5\;mW/cm^2$), NDMA concentration ($X_2$) (range: 100~300 uM) and pH ($X_2$) (rang: 3~9) which consisted of 3 levels in each factor and 4 responses ($Y_1$ (% of NDMA removal), $Y_2$ (dimethylamine (DMA) reformation (uM)), $Y_3$ (dimethylformamide (DMF) reformation (uM), $Y_4$ ($NO_2$-N reformation (uM)) were set up to estimate the prediction model and the optimization conditions. The results of prediction model and optimization point using the canonical analysis in order to obtain the optimal operation conditions were $Y_1$ [% of NDMA removal] = $117+21X_1-0.3X_2-17.2X_3+{2.43X_1}^2+{0.001X_2}^2+{3.2X_3}^2-0.08X_1X_2-1.6X_1X_3-0.05X_2X_3$ ($R^2$= 96%, Adjusted $R^2$ = 88%) and 99.3% ($X_1:\;4.5\;mW/cm^2$, $X_2:\;190\;uM$, $X_3:\;3.2$), $Y_2$ [DMA conc] = $-101+18.5X_1+0.4X_2+21X_3-{3.3X_1}^2-{0.01X_2}^2-{1.5X_3}^2-0.01X_1X_2+0.07X_1X_3-0.01X_2X_3$ ($R^2$= 99.4%, 수정 $R^2$ = 95.7%) and 35.2 uM ($X_1$: 3 $mW/cm^2$, $X_2$: 220 uM, $X_3$: 6.3), $Y_3$ [DMF conc] = $-6.2+0.2X_1+0.02X_2+2X_3-0.26X_1^2-0.01X_2^2-0.2X_3^2-0.004X_1X_2+0.1X_1X_3-0.02X_2X_3$ ($R^2$= 98%, Adjusted $R^2$ = 94.4%) and 3.7 uM ($X_1:\;4.5\;$mW/cm^2$, $X_2:\;290\;uM$, $X_3:\;6.2$) and $Y_4$ [$NO_2$-N conc] = $-25+12.2X_1+0.15X_2+7.8X_3+{1.1X_1}^2+{0.001X_2}^2-{0.34X_3}^2+0.01X_1X_2+0.08X_1X_3-3.4X_2X_3$ ($R^2$= 98.5%, Adjusted $R^2$ = 95.7%) and 74.5 uM ($X_1:\;4.5\;mW/cm^2$, $X_2:\;220\;uM$, $X_3:\;3.1$). This study has demonstrated that the response surface methodology and the Box-Behnken statistical experiment design can provide statistically reliable results for decomposition and by-products of NDMA by the UV photolysis and also for determination of optimum conditions. Predictions obtained from the response functions were in good agreement with the experimental results indicating the reliability of the methodology used.

A Study on Developing Customized Bolus using 3D Printers (3D 프린터를 이용한 Customized Bolus 제작에 관한 연구)

  • Jung, Sang Min;Yang, Jin Ho;Lee, Seung Hyun;Kim, Jin Uk;Yeom, Du Seok
    • The Journal of Korean Society for Radiation Therapy
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    • v.27 no.1
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    • pp.61-71
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    • 2015
  • Purpose : 3D Printers are used to create three-dimensional models based on blueprints. Based on this characteristic, it is feasible to develop a bolus that can minimize the air gap between skin and bolus in radiotherapy. This study aims to compare and analyze air gap and target dose at the branded 1 cm bolus with the developed customized bolus using 3D printers. Materials and Methods : RANDO phantom with a protruded tumor was used to procure images using CT simulator. CT DICOM file was transferred into the STL file, equivalent to 3D printers. Using this, customized bolus molding box (maintaining the 1 cm width) was created by processing 3D printers, and paraffin was melted to develop the customized bolus. The air gap of customized bolus and the branded 1 cm bolus was checked, and the differences in air gap was used to compare $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$ and $V_{95%}$ in treatment plan through Eclipse. Results : Customized bolus production period took about 3 days. The total volume of air gap was average $3.9cm^3$ at the customized bolus. And it was average $29.6cm^3$ at the branded 1 cm bolus. The customized bolus developed by the 3D printer was more useful in minimizing the air gap than the branded 1 cm bolus. In the 6 MV photon, at the customized bolus, $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of GTV were 102.8%, 88.1%, 99.1%, 95.0%, 94.4% and the $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of branded 1cm bolus were 101.4%, 92.0%, 98.2%, 95.2%, 95.7%, respectively. In the proton, at the customized bolus, $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of GTV were 104.1%, 84.0%, 101.2%, 95.1%, 99.8% and the $D_{max}$, $D_{min}$, $D_{mean}$, $D_{95%}$, $V_{95%}$ of branded 1cm bolus were 104.8%, 87.9%, 101.5%, 94.9%, 99.9%, respectively. Thus, in treatment plan, there was no significant difference between the customized bolus and 1 cm bolus. However, the normal tissue nearby the GTV showed relatively lower radiation dose. Conclusion : The customized bolus developed by 3D printers was effective in minimizing the air gap, especially when it is used against the treatment area with irregular surface. However, the air gap between branded bolus and skin was not enough to cause a change in target dose. On the other hand, in the chest wall could confirm that dose decrease for small the air gap. Customized bolus production period took about 3 days and the development cost was quite expensive. Therefore, the commercialization of customized bolus developed by 3D printers requires low-cost 3D printer materials, adequate for the use of bolus.

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A Study on Antiulcer Effects of Opuntia dillenii Haw. on Stomach Ulcer Induced by Water-immersion Stress in Rats (랫드의 스트레스성 위궤양에 대한 Opuntia dillenii Haw.(선인장)의 항궤양작용에 관한 연구)

  • 이후장;이용욱;김정현
    • Journal of Food Hygiene and Safety
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    • v.13 no.1
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    • pp.53-61
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    • 1998
  • This study was performed to investigate the antiulcer effects of Opuntia dillenii Haw. on the stomach ulcer induced by restraint and water-immersion stress in rats. For this experiment, 48 male Sprague-Dawley strain were used. The experimental groups were divided into four: a control (C) and 3 Opuntia dillenii Haw. treatment groups (E-1, E-2, E-3). Each dose of Opuntia dillenii Haw. was 30 mg/kg bw (E-1), 60 mgfKg bw (E-2) and 120 mg/kg bw (E-3). The rats were allocated to each group by 12 and observed for 4 weeks. The results were as following: 1. The stomach surface pH in each group showed no significant difference, but the values of Opuntia dillenii Haw. treatment groups were higher than the value of the control group. 2. The gastric wall mucus was increased in all Opuntia dillenii Haw. treatment groups compared with the control group. Especially in E-1 difference was higher (p<0.05) and in E-2 difference was significantly higher (p<0.01). 3. At shear rate 11.25, 45.0, 90.0, $225\;sec^{-1}$, whole blood viscosity and plasma viscosity were measured. Most of the values of Opuntia dillenii Haw. treatment groups were low compared with that of the control group. At shear rate 90.0, $225\;sec^{-1}$ the values of whole blood viscosity in E-1 were significantly low (p<0.05) and at shear rate 11.25, $45.0\;sec^{-1}$, more significant (p<0.01). At shear rate 11.25, 45.0, 90.0, $225\;sec^{-1}$ the values of whole blood viscosity in E-2 were significantly low (p<0.01). At shear rate $90.0\;sec^{-1}$ the value of plasma viscosity in E-1 was significantly low (p<0.05) and at shear rate 90.0, $225\;sec^{-1}$ the values of plasma viscosity in E-2 we resignificantly low (p<0.01). 4. Less severe ulcers were obsered in Opuntia dillenii Haw. treatment groups than in the control group. Especially E-1 groups tissues had only slight ulcers and necrosis of tissue was not observed in this group. From the results of this study, it can be concluded that the oral administratio-n of Opuntia dillenii Haw. results in protection of stomach ulcer by stimulating the secretion of gastric mucus and improving the gastric mucosal microcirculation.

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Evaluation of indirect N2O Emission from Nitrogen Leaching in the Ground-water in Korea (우리나라 농경지에서 질소의 수계유출에 의한 아산화질소 간접배출량 평가)

  • Kim, Gun-Yeob;Jeong, Hyun-Cheol;Kim, Min-Kyeong;Roh, Kee-An;Lee, Deog-Bae;Kang, Kee-Kyung
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.6
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    • pp.1232-1238
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    • 2011
  • This experiment was conducted to measure concentration of dissolved $N_2O$ in ground-water of 59 wells and to make emission factor for assessment of indirect $N_2O$ emission at agricultural sector in agricultural areas of Gyeongnam province from 2007 to 2010. Concentrations of dissolved $N_2O$ in ground-water of 59 wells were ranged trace to $196.6{\mu}g-N\;L^{-1}$. $N_2O$ concentrations were positively related with $NO_3$-N suggesting that denitrification was the principal reason of $N_2O$ production and $NO_3$-N concentration was the best predictor of indirect $N_2O$ emission. The ratio of dissolved $N_2O$-N to $NO_3$-N in ground-water was very important to make emission factor for assessment of indirect $N_2O$ emission at agricultural sector. The mean ratio of $N_2O$-N to $NO_3$-N was 0.0035. It was greatly lower than 0.015, the default value of currently using in the Intergovernmental Panel on Climate Change (IPCC) methodology for assessing indirect $N_2O$ emission in agro-ecosystems (IPCC, 1996). It means that the IPCC's present nitrogen indirect emission factor ($EF_{5-g}$, 0.015) and indirect $N_2O$ emission estimated with IPCC's emission factor are too high to use adopt in Korea. So we recommend 0.0034 as national specific emission factor ($EF_{5-g}$) for assessment of indirect $N_2O$ emission at agricultural sector. Using the estimated value of 0.0034 as the emission factor ($EF_{5-g}$) revised the indirect $N_2O$ emission from agricultural sector in Korea decreased from 1,801,576 ton ($CO_2$-eq) to 964,645 ton ($CO_2$-eq) in 2008. The results of this study suggest that the indirect Emission of nitrous oxide from upland recommend 0.0034 as national specific emission factor ($EF_{5-g}$) for assessment of indirect $N_2O$ emission at agricultural sector.

The study for the roles of intratracheally administered histamine in the neutrophil-mediated acute lung injury in rats: (호중구를 매개하는 백서의 급성 폐손상의 병리가전에 있어 기도내로 투여한 히스타민의 역활에 관하여)

  • Koh, Youn-Suck;Hybertson, Brooks M.;Jepson, Eric K.;Kim, Mi-Jung;Lee, In-Chul;Lim, Chae-Man;Lee, Sang-Do;Kim, Dong-Soon;Kim, Won-Dong;Repine, John E.
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.3
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    • pp.308-322
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    • 1996
  • Background : Neutrophils are considered to play critical roles in the development of acute respiratory distress syndrome. Histamine, which is distributed abundantly in lung tissue, increases the rolling of neutrophills via increase of P-selectin expression on the surface of endothelial cells and is known to have some interrelationships with IL-1, IL-8 and TNF-$\alpha$. We studied to investigate the effect of the histamine on the acute lung injury of the rats induced by intratracheal insufflation of TNF-$\alpha$ which has less potency to cause lung injury compared to IL-1 in rats. Methods : We intratracheally instilled saline or TNF(R&D, 500ng), IL-1(R&D, 50ng)or histamine of varius dose(1.1, 11 and $55\;{\mu}g/kg$) with and without TNF separately in Sprague-Dawley rats weighing 270-370 grams. We also intratracheally treated IL-1(50ng) along with histamine($55\;{\mu}g/kg$). In cases, there were synergistic effects induced by histamine on the parameters of TNF-induced acute lung injury, antihistamines(Sigma, mepyramine as a $H_1$ receptor blockade and ranitidine as a $H_2$ receptor blockade, 10 mg/kg in each)were co-administered intravenously to the rats treated TNF along with histamine($1.1\;{\mu}g/kg$) intratraeheally. Then after 5 h we measured lung lavage neutrophil numbers, lavage cytokine-induced neutrophil chemoattractants(CINC), lung myeloperoxidase activity(MPO) and lung leak. We also intratracheally insufflated TNF with/without histamine($11\;{\mu}g/kg$), then after 24 h measured lung leak in rats. Statistical analyses were done by Kruskal-Wallis nonparametric ANOVA test with Dunn's multiple comparison test or by Mann-Whitney U test. Results : We found that rats given TNF, histamine alone(11 and $55\;{\mu}g/kg$), and TNF with histamine(l.1, 11, and $55\;{\mu}g/kg$) intratracheally had increased (p<0.05) lung MPO activity compared with saline-treated control rats. TNF with histamine $11\;{\mu}g/kg$ had increased MPO activity (P=0.0251) compared with TNF-treated rats. TNF and TNF with histamine(1.1, 11, and $55\;{\mu}g/kg$) intratracheally had all increased (p<0.05) lung leak, lavage neutophil numbers and lavage CINC activities compared with saline. TNF with histamine $1.1\;{\mu}g/kg$ had increased (p=0.0367) lavage neutrophil numbers compared with TNF treated rats. But there were no additive effect of histamine with TNF compared with TNF alone in acute lung leak on 5 h and 24 h in rats. Treatment of rats with the $H_1$ and $H_2$ antagonists resulted in inhibitions of lavage neutrophil accumulations and lavage CINC activity elevations elicited by co-treated histamine in TNF-induced acute lung injury intratracheally in rats. We also found that rats given IL-1 along with histamine intratracheally did not have increase in lung leak compared with IL-1 treated rats. Conclusion : Histamine administered intratracheally did not have synergistic effects on TNF-induced acute lung leak inspite of additive effects on increase in MPO activity and lavage neutrophil numbers in rats. These observations suggest that instilling histamine intratracheally would not play synergistic roles in neutrophil-mediated acute lung injury in rats.

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