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Drought Stress Influences Photosynthesis and Water Relations Parameters of Synurus deltoides (건조스트레스가 수리취의 광합성 및 수분관련 특성에 미치는 영향)

  • Lee, Kyeong-Cheol;Lee, Hak Bong
    • Journal of Korean Society of Forest Science
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    • v.106 no.3
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    • pp.288-299
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    • 2017
  • This study was conducted to find out the influence of drought stress on physiological responses of Synurus deltoides. Drought stress was induced by withholding water for 25 days. Leaf water potentials were decreased of both predawn (${\Psi}_{pd}$) and mid-day (${\Psi}_{mid}$) with increasing drought stress, but water saturation dificit (WSD) was 7 times increased. ${\Psi}_{pd}-{\Psi}_{mid}$ showed the significant difference of 0.22~0.18 MPa in stressed before 10 days, and nonsignificant as treatment time became longer. A strong reduction of stomatal conductance ($gH_2O$) and stomatal transpiration rate (E) were observed after 15 days of drought stress Significant reductions of net apparent quantum yield (${\Phi}$) and maximum photosynthesis rate ($Pn_{max}$) were observed after 20 days of drought stress; However, water use efficiency (WUE) was shown the opposite trend. This implies that decrease of photosynthesis rate may be due to an inability to regulate water and $CO_2$ exchanged through the stomata. From JIP analysis, flux ratios (${\Psi}_O$ and ${\Phi}_{EO}$) and performance index on absorption basis ($PI_{ABS}$) were dramatically decreased withholding water after 15 days, which reflects the relative reduction of photosystem II activity. The leaf of S. deltoides showed osmotic adjustment of -0.35 MPa at full turgor and -0.40 MPa at zero turgor, and also cell-wall elastic adjustment of 9.4 MPa, indicating that S. deltoides tolerate drought stress through osmotic adjustment and cell-wall elastic adjustment. The degree of change in water relations parameters such as Vo/DW, Vt/DW decreased with increasing drought stress. This result showed that S. deltoides was exhibited a strong reduction of photosynthetic activity to approximately -0.93 MPa of predawn leaf water potential, and both of osmotic adjustment and cell-wall elastic adjustment in drought stress condition appears to be an important adaptation for restoration in this species.

Development of an Efficient Screening System for Resistance of Watermelon Plants to Didymella bryoniae (수박 덩굴마름병에 대한 효율적인 저항성 검정 방법 개발)

  • Lee, Ji Hyun;Jang, Kyoung Soo;Choi, Yong Ho;Kim, Jin-Cheol;Choi, Gyung Ja
    • Research in Plant Disease
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    • v.22 no.2
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    • pp.72-80
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    • 2016
  • Gummy stem blight, caused by the fungus Didymella bryoniae, is major disease of watermelons worldwide. The objective of the present study was to establish an efficient screening system to identify watermelon resistant to D. bryoniae. An GSB3 isolate was prepared from a watermelon plant showing typical symptoms of gummy stem blight in Haman-gun and identified as D. bryoniae based on molecular analysis of internal transcribed spacer sequence. A simple mass-production technique of inoculum was developed based on spore production of D. bryoniae GSB3 under several incubation conditions and their virulence on watermelon plants. Resistance degrees of 22 commercial watermelon cultivars to the GSB3 isolate were evaluated. Among them, four watermelon cultivars showing different degree of resistance response were selected for further study. Development of disease on the cultivars according to various conditions including inoculum concentrations, incubation periods in dew chamber, and incubation temperatures was investigated. From the results, we suggest an efficient screening method for resistant watermelon cultivars to gummy stem blight. Seeds of watermelon cultivar are sown and grown in a greenhouse until plant stage of 2-fully expanded leaves. Seedlings are inoculated with D. bryoniae by spraying spore suspension of the fungus at a concentration of $5.0{\times}10^5spores/ml$. The infected plants are incubated in humidity chamber at $25^{\circ}C$ for 48 hours and then transferred to a growth chamber at $25^{\circ}C$ and 80% relative humidity with 12-hour light a day. Three to four days after inoculation, disease severity of the plant are measured using percentage of infected leaf area.

Emission of $CO_2$ and $NH_3$ from Mixed Composting Cattle Manure with Rice Hull by Static Whindrow and Aerated Static Pile Methods, and Grow of Tomato on It under Greenhouse Condition (우분뇨와 왕겨 혼합물의 정치식과 통기퇴적식 퇴비화 과정에서 $CO_2$$NH_3$ 가스 발생과 토마토 생육)

  • Sohn, Bo-Kyoon;Hong, Ji-Hyung;Park, Keum-Joo;Yang, Won-Mo;Kim, Kil-Yong;Rim, Yo-Sup
    • Korean Journal of Environmental Agriculture
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    • v.16 no.2
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    • pp.119-123
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    • 1997
  • This study was performed to evaluate the influence of composting process with an intermittent aeration on the variation of rhizosphere soil temperature, $CO_2$ and $NH_3$ release, and the growth reponse of tomato plantlet in traditional and composting greenhouse. As the temperature of composting materials increased, rhizosphere soil temperature in 30cm depth rose up to $32^{\circ}C$ at one week after introduction. This was $18^{\circ}C$ higher than that of traditional greenhouse. After 20 days of active composting, temperature of rhizosphere soil started to decrease and remained constant at $23^{\circ}C$ after 35 days. For the traditional greenhouse, the averaged temperature ranged at $14{\sim}15^{\circ}C$. This results showed that composting greenhouse had the greater effect on increasing the underground temperature. Average value of evoluted $CO_2$ from the composting greenhouse for 70 days was $782{\sim}1154ppm$. This was $1.7{\sim}2.6$ times higher than that of the traditional greenhouse with an average of $440{\sim}462ppm$. $NH_3$ release was highest during $2{\sim}10$ days in intermittent aerated composting and reached to 134 ppm maximum on the 5th day, then decreased rapidly, and maintained at $3{\sim}4ppm$ after 17 days. Increased photosynthesis due to the $CO_2$ gas and a favorable rhizosphere environment due to the increased underground temperature resulted in improved growth, yield, and Brix degree of tomato fruit.

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Effect of Quercus acutissima CARRUTHERS Extracts on the Lipid Metabolism (도토리추출물이 흰쥐의 체내 지질대사에 미치는 영향)

  • Sung, In-Suk;Kim, Myung-Joo;Cho, Soo-Yeul
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.2
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    • pp.327-333
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    • 1997
  • This study was conducted to investigate the effect of Quercus acutissima CARRUTHERS extracts on lipid metabolism. Sprague-Dawley male rats$(110{\pm}10g)$ were fed on containing normal and high fat diets. They were orally administrated(0.02g/100g B.W.) of Quercus aculissima CARRUTHERS ethylacetate-extract and water-extract at the same time once a day respectively. The rats were sacrificed after 6 weeks of feeding periods. In high fat diet group, liver and heart weight were increased but kidney weight was decreased. Contents of total lipid, triglyceride and phospholipid were increased in high fat diet groups. But the degree of increment was reduced by administration of Quercus acutissima CARRUTHERS extracts and water extract was more effective. Significant decrease in serum total lipid content by administration Quercus acutissima CARRUTHERS extracts was not due to decrease of triglyceride content but total cholesterol content. Whereas HDL-cholesterol content was significantly decreased in high fat diet group and improved by administration of Quercus acutissima CARRUTHERS extracts. Total lipid, triglyceride and total cholesterol contents in liver were also increased in high fat diet group but phospholipid content was significantly decreased. The results indicate that Quercus acutissima CARRUTHERS extracts were effective in preventing hyperlipidemia and water extract was more effective.

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A study on ceremonial costume and Confucianism is Chosun Dynasty - Focusing on Men's Po - (조선시대(朝鮮時代) 유교사상(儒敎思想)과 의예복연구(儀禮服硏究) - 남자(男子) 포(袍)를 중심(中心)으로 -)

  • Lee, Sun-Jae
    • Journal of the Korean Society of Costume
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    • v.16
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    • pp.221-229
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    • 1991
  • This thesis aims at reviewing the wearing aspect and formation of Chosun ceremonial dresses for meal and finding out the thought reflected by them from the standpoint that dresses themselves should be taken as one of the phenomena in culture. That is men's ceremonial costumes and confucian costumes of the royal family and the gentry family in Chosun is reviewed focused on the formation and the wearing aspect of Po, Which is a kind of them. And in the context of the phase of the times. I also considered the thoughts reflected on the clothes such as confucianism, Ying & Yang Theory, and the symbol and the thoughts of patterns in relation to the clothes. Confucian influence was the main force for the Chosun prohibitions for clothes. The major reasons for the prohibitions for clothes were as follows. First, they reflected confucian Chung myoung chooui(the principle that everything should be where it belongs). That is the prohibitions for clothes were used in the means to maintain feudalistic social order. influenced by social rank system. Second, they reflected confucian ethics in the means to recover social disciplines with the maintenance of traditional customs. This shows well in the restriction of luxurious items in dressing included the prohibitions for clothes. Third, they reflected Chosun's toadysm toward China. With the influx of Chinese style of dressing then government even changed the style of uniforms for public officials into that of Chinese resulting in dual styles of dressing. Ying & Yan Theory greatly affected the colors of Korean clothes and reflected toadysm toward China. too. The theory was embodied by prohibition of such colors for clothes as white, gray, and jade green. I reviewed the twelve patterns on Myunpok, Ten-Longivity patterns and Four-Gracious plants patterns in order to analyze the symbolism and thoughts of patterns for clothes. Nansam, Dopo, and Shimui worn by confucian scholars ensures that those clothes bears confucianism and philosopical factors. As shimui was worn by many people it appears in Chosun scholars' studies and a Chinese book called "Yeki". I reviewed the origin, procession, and ornaments of four ceremonial clothes and tried to find out the confucianism in them. First, In Kwanrei (the coming-of-age ceremony) remained ancestor worship and respect for manners. The clothes for this ceremony granted the rights and responsibilities of and adult to the wearer. The royal Kwanreipok had different dresses for each rank. As Samgapok, the crown prince wore Iksunkwan and Konryongpo for the first ritual, Wonryukwan and Kangsapo for the second, and Myunrukwan and Konpok for the third. The rank of the King's grandson was lower than the crown prince's. This example shows that Chosun people respected manners and thought the basic confucianism "God and people are equal." at the Royal court. Second, as Honreipok(wedding gown), the crown prince wore Myunrukwan and Konpok for Daereipok, Wonyukwan and Kangsapo for Napjing and Tongwoo, and Iksunkwan and Konryongpo for Chekbinui. But common people were allowed to wear an official outfit only for wedding in the means of congratulation on the most important day of their life. Wedding gowns which reflected Ying and Yang Theory emphasized the thought that union of a man and a wife is the most important event in life. Third, Sangrei(funeral) was the last ritual of a human being to send off the deceased. The mourning dresses expressed lamentation of the people left behind. Five-Dress-System for each the relative degree of familarity showed the solemnity and formality, which represented the formality of confucianism and ancestor worship. I reviewed the mourning dresses by dividing them into royal, Yangban's, and commons. They were featured by the fact that there was only one style for every walk of life. It is construed that anyone in mourning can wear the same clothes since he feels the same way regardless of his social rank. Fourth, Chereipok(sacrificial rite dresses) had different styles for each social rank. The King wore Myunpok(Kuryumyun and Kujangpok) were recorded to be worn first in the fourth year of King Taecho's ruling. The crown prince wore Palryumyun and Chiljangpok for sacrificial rite dress which was finally settled when King Sejong was in power. Common people wore Dopo, Shimui for the rite dress in the beginning of the Chosun Era and wore Dopo after Japanese invasion of Korea in 1592. In conclusion, confucianism played the main role in ceremonial dress system of Chosun and that was because it emphasized the ethics of action in life, which was different from other religions. It is true that cause-oriented thoughts and Chung myoung chooui in confucianism drove all ceremonies to extreme manners, discriminating the people who belonged to the lower social rank, and resulting in extremly luxurious life style. However, they also created a unique trend and clothes culture in the Chosun Era. I wish that this thesis provieds important information and direction for furthur studies in the future.

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The Necessity for Coronary Angiography in Atherosclerotic Arterial Obstruction in the Lower Extremities and the Clinical Features of Accompanied Coronary Arterial Diseases (죽상동맥경화성 하지동맥폐쇄증에서 관상동맥조영술의 필요성 및 동반되는 관상동맥 질환의 양상)

  • Lee Jae-Wook;Yeom Wook;Park Young-Woo;Shin Hwa-Kyun;Won Yong-Soon
    • Journal of Chest Surgery
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    • v.39 no.8 s.265
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    • pp.619-625
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    • 2006
  • Background: Peripheral arterial disease is frequently accompanied with systemic arteriosclerosis and more than half of the cause of deaths is due to the development of coronary arterial disease. Moreover, it is known that the most frequent cause of death after a bypass surgery of chronic arterial obstruction is heart related complications. Especially in patients with atherosclerotic arterial obstruction in the lower extremities who had no history of heart disease or had no presenting symptoms of ischemic heart disease showed a high rate of postoperative mortality and for this reason we suggest preoperative evaluation in these patients to evaluate whether or not coronary arterial disease is accompanied. Material and Method: Since Feb. 2001 to Oct. 2004, we analyzed 52 patients who were operated on for atherosclerotic arterial obstruction in the lower extremities, with the exception of patients with a past history of heart disease or symptoms of ischemic heart disease. They underwent on the same day a coronary and femoral angiography for evaluation of accompanying coronary arterial disease. Of among these patients, we compared those who received bypass surgery of the arteries of the peripheral extremities alone to those who underwent combined coronary artery bypass surgery. Result: 63% of the reported cases of atherosclerotic arterial obstruction in the lower extremities were accompanied with coronary arterial disease. Old age, hypertension, diabetes mellitus, smoking, and hypercholesterolemia are known risk factors for arteriosclerosis and of these, only old age and hypertension had statistically significance in patients with severe atherosclerotic arterial obstruction in the lower extremities accompanied with coronary arterial disease. Diabetes, smoking, and hypercholesterolemia showed no statistical significance in this group. With the increase in severity of the range and the degree of atherosclerotic arterial obstruction, coronary arterial disease is frequently accompanied and its severity also increased. Patients who received both peripheral artery and coronary artery bypass surgery showed no difference in the period of hospitalization and ICU stay period compared with patients who received bypass surgery of the arteries of the lower extremities alone. Conclusion: Patients with atherosclerotic arterial obstruction in the lower extremities without symptoms of ischem to evaluate coronary arterial disease for active treatment, especially in the patients with old age, hypertension and high AVD scores.

Effect of a Combined Treatment with Uniconazole, Silver Thiosulfate on Reduction of Ozone Injury in Tomato Plant (Uniconazole 과 Silver Thiosulfate 의 복합처리가 토마토의 오존피해경감에 미치는 효과)

  • Ku, Ja-Hyeong;Won, Dong-Chan;Kim, Tae-Il;Krizek, Donld T.;Mirecki, Roman M.
    • Korean Journal of Environmental Agriculture
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    • v.11 no.1
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    • pp.50-58
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    • 1992
  • Studies were conducted to determine the combined effect of uniconazole [(E) -1-(4-chlorophenyl)-4, 4-demethyl 2-(1,2,4 triazol-1-yl)-1-penten-3-ol] and silver thiosulfate $[Ag {(S_2O_3)}^3\;_2-]$ (STS) on reduction of ozone injury in tomato plants(Lycopersicon esculentum Mill. 'Pink Glory'). Plants were given a 50ml soil drench of uniconazole at concentrations of 0, 0.001, 0.01 and 0.1 mg/pot at the stage of emerging 4th leaf. Two days prior to ozone fumigation, STS solution contained 0.05% Tween-20 was also sprayed at concentrations of 0, 0.3 and 0.6 mM. Uniconazole at 0.01 mg/pot and STS at 0.6 mM were effective in providing protection against ozone exposure(20h at 0.2ppm) without severe retardation of plant height and chemical phytotoxicity, respectively. Combined treatment with uniconazole, STS significantly reduced ozone injury at the lower concentration than a single treatment with uniconazole or STS. Uniconazole treatment reduced plant height, stem elongation and transpiration rate on a whole plant level and increased chlorophyll concentration. STS did not give any effect on plant growth and chlorophyll content but increased transpiration rate in non-ozone-fumigated plants. Ethylene production in the leaves of ozone-fumigated plants was decreased by uniconazole and STS pretreatment, but there was no protective effect on epinasty of leaves in uniconazole-treated plants. STS increased ethylene production in non-ozone-fumigated plants, but it significantly reduced the degree of epinasty and defoliation of cotyledons when plants were exposed to ozone. Uniconazole slightly increased superoxide dismutase and peroxidase activities. But STS showed little or no effects on such free radical scavengers. Day of flowering after seeding was shortened and percentages of fruit set were increased by uniconazole treatment. STS was highly effective on protecting reduction of fruit set resulting from ozone fumigation. These results suggest that combined use of uniconazole and STS should provide miximum protection against ozone injury without growth retardation resulting in yield loss.

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Changes in Lymphocyte DNA Damage and Antioxidant Status after Supplementing Propolis to Korean Smokers: A Placebo-Controlled, Double-Blind Cross-Over Trial (프로폴리스 섭취 후 흡연자의 임파구 DNA 손상도 및 항산화 상태의 변화: 이중맹검 교차 인체시험)

  • Kang, Myung-Hee;Lee, Hye-Jin;Kim, Mi-Kyung;Sung, Mi-Kyung;Kwon, O-Ran;Park, Yoo-Kyoung
    • Journal of Nutrition and Health
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    • v.42 no.5
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    • pp.442-452
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    • 2009
  • Smoking has been known to exacerbate the initiation and propagation of oxidative stresses. Efforts have been made to reduce the smoking-induced oxidative stresses using commercial dietary supplements. Propolis is the resinous substance collected by bees from the leaf buds and bark of trees, especially poplar and conifer trees. In this trial, we examined whether a daily supplementation of 800 mg propolis can protect endogenous lymphocytic DNA damage and modulate antioxidative enzyme activities and the level of antioxidant vitamin in smokers using a placebo-controlled, doubleblinded cross-over trial. After two weeks of running-in period, 29 smokers (mean age 34.38 ${\pm}$ 1.73) received 6 tablets/day of either propolis or placebo pills for 4 weeks. After 2 weeks of washout period the subjects switched they pills for cross-over study. The degree of DNA damage (assessed by tail DNA, tail length and tail moment) was not significantly changed with propolis intake or placebo intake. Similarly, total antioxidant status (TAS) remained at the same level regardless of the treatment. Erythrocyte catalase, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), plasma vitamin C and tocopherol level did not differ before and after propolis treatment, and did not differ between treatments. Putting all these results together, we would suggest that it is still too early to claim that propolis possess antioxidative activities.

The effects of the mulberry and silkworm intake on androgen receptor mRNA and myogenic regulatory factors expression of rats muscle for resistance exercise (오디와 누에 섭취가 rats의 저항성 운동에 따른 androgen receptor mRNA와 myogenic regulatory factors의 발현에 미치는 영향)

  • Yang, Sung Jun;Kim, Chang Yong;Lee, Jo Byoung;Kang, Sung Sun;Lee, Jong Jin
    • Journal of Sericultural and Entomological Science
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    • v.51 no.2
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    • pp.99-106
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    • 2013
  • The purpose of this study is to investigate the effects of supplementation of mulberry powder, mulberry extract and silkworm powder during the 8 weeks of resistance exercise on Androgen receptor(AR) mRNA and Myogenic regulatory factors(MRFs) expression of rats muscle. Fifty males, Sprague-Dawley rat, were randomly divided into 5 groups: CON(control group, n = 10), REG(resistance exercise group, n = 10), MP REG(mulberry powder intake and resistance exercise group, n = 10), ME REG(mulberry extract intake and resistance exercise group, n = 10) and SP REG(silkworm powder intake and resistance exercise group, n = 10). After climbing the ladder without weights during the 1 week of adaptation period, the rats in the resistance exercise group were trained to climb a 0.98-m vertical(80 degree incline) ladder with weights in their tail during 7 weeks(10 times each day, 2 days per week). After exercise, the skeletal muscle was extracted from the flexor hallucis longus. After separating the total ribonucleic acid (RNA) of each group, quantitative polymerase chain reaction was used to analyze RNA quantitatively. AR mRNA and MRFs expression revealed that all of the treated groups had significantly difference. AR mRNA expression increased in ME REG $6.24{\pm}1.85$ and SP REG $9.68{\pm}0.28$ fold compared to CON. Myod mRNA expression increased in MP REG $6.04{\pm}0.47$, ME REG $4.31{\pm}1.58$ and SP REG $8.11{\pm}0.57$ fold compared to CON. And myogenin mRNA expression increased in MP REG $4.11{\pm}0.42$, ME REG $4.12{\pm}0.45$ and SP REG $6.50{\pm}0.61$ fold compared to CON. In conclusion, during the resistance exercise, providing mulberry and silkworm gives positive effect on AR mRNA and MRFs expression increase.

Effect of the Paclitaxel and Radiation on the Large Bowel Mucosa of the Rat (횐쥐의 대장점막에 Paclitaxel(Taxol)과 방사선조사의 효과)

  • Lee Kyung-Ja
    • Radiation Oncology Journal
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    • v.17 no.1
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    • pp.57-64
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    • 1999
  • Purpose : Paclitaxel is a chemotherapeutic agent with a potent microtubule stabilizing activity that arrests mitosis at G2-M phase of cell cycle which is the most radiosensitive period. Therefore paclitaxel is considered as a cell cycle-specific radiosensitizer. This study investigates the effect of paclitaxel on the radiation response of the normal large bowel mucosa of the rat. Materials and Methods: The rats were divided into the three groups i.e., single intraperitoneal infusion of paclitaxel (10 mg/kg), a single fraction of irradiation (8 Gy, x-ray) to the whole abdomen, and a combination of irradiation (8 Gy, x-ray) given 24 hours after paclitaxel infusion. The histological changes as well as kinetics of mitotic arrest and apoptosis were evaluated on the large bowel mucosa at 6 hours, 1 day, 3 days and 5 days after treatment with paclitaxel alone, radiation alone and combination of paclitaxel and radiation. Results : The incidence of the mitotic arrest was not increased by paclitaxel infusion. The apoptosis appeared in 24 hours after paclitaxel infusion, and the histopathologic changes such as vesiculation, atypia and reduction of the goblet cell of the mucosa of the large bowel were demonstrated during the period from 6 hours to 3 days after, and returned to normal in 5 days after paclitaxel infusion. In irradiated group, the apoptosis was increased in 6 and 24 hours after irradiation, and the histopathologic changes of the mucosa were appeared in 24 hours and markedly increased in 3 days and returned to normal in 5 days. In combined group of irradiation and paclitaxel infusion, the apoptosis was appeared in 3 days and the histopathologic changes appeared during the period from 6 hours to 3 days after infusion. On the basis of the incidence of apoptosis and the degree of the histopathologic changes of the large bowel mucosa, there seemed to be additive effect by paclitaxel on radiation rather than sensitizing effect. Conclusions: The histopathological changes of large bowel mucosa in combined group compared to radiation alone group suggested an additive effect of paclitaxel on radiation response in the large bowel of rat.

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