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The Status, Problems and Countermeasure of Direct Rice Seeding in Honam Province - On Weed control - (호남지방(湖南地方) 직파재배(直播栽培)의 현황(現況), 문제점(問題點) 및 대책(對策) - 잡초방제적(雜草防除的) 측면(側面)에서 -)

  • Ryang, Hwan-Seung;Kim, Jong-Seog
    • Korean Journal of Weed Science
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    • v.12 no.3
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    • pp.271-291
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    • 1992
  • This study was conducted to survey the situation of direct rice seeding in Honam province in Korea to investigate problems and seek countermeasure of weed control in direct rice seeding. The total area of direct rice seeding in the south-western part of Korea (Chonbuk, Chonnam, and Chungnam) was 1650.8ha (732.1ha for direct seeding in dry field and 918.7ha for direct seeding in flooding field) in 1992. The followings are summary of the study. 1. In case of direct rice seeding in dry field, butachlor EC and G at 3 to 5 DAS was mostly selected by farmers to control weeds in dry field. Benthiocarb or chlornitrofen was also used in few cases. At 10 to 14 DAS just before rice emergence, tank misture of butachlor EC and paraquat was treated by some farmers. At 35 to 40 days, after flooding mixture of sulfonylurea derivatives was sequentially applied. Surviving weeds including barnyardgrass were finally controlled by mixture of bentazon+quinclorac WP foliage application. 2. In case of direct rice seeding in flooding field, weed control were mostly unsuccessful partially due to wrong selection of herbicide and missing the optimum application time. Three relatively successful weed control in the survey were summarized as follows. 1) Oxadiazon EC, butachlor or benthiocarb were treated just after puddling(5 to 7 days before seeding). then mixture of bentazone+quinclorac WP or sulfonylurea derivatives was sequently applied to control remaining weeds at 20 days after seeding. 2) Mixtures of bensulfuronmethyl+dimepiperate G, pyrazosulfuronethyl+molinate G, or bensulfuronmethyl+mefenacet+dymron G were applied at 11 days after puddling when barnyardgrass were at 2.0 leaf stage. Phytotoxicity was not found in case of mixture of bensulfuronmethyl+dimepiperate G but found in the other two cases but disappeared later. 3) Mixtures of bensulfuronmethyl+quinclorac G., pyrazosulfuronethyl+quinclorac G or betazone and quinclorac G were treated after 18 to 20 days after puddling when barnyardgrass was within 3.0 leaf stage. It showed good weed control in both annuals and perrenials without phytotoxicity. On the contrary, other sulfonylurea derivatives such as middle periodic herbicide showed poor weed control against barnyardgrass, so that sequential treatment of bentazone+quinclorac WP mixture was required. 3. Herbicidal characteristics and optimum application time of 45 rigistered herbicides in Korea were analyzed to discover new substitute for quinclorac mixture, that showed excellent weed control against barnyardgrass at its 3 leaf stage or older. The analysis revealed that 70% of herbicides were for preemergence and the others were post periodic herbicide. Most farmers favor to apply herbicide when rice seedlings completely rooted, at this time barnyardgrass are at 2.5-3.0 leaf stage. Therefore herbicide of which optimum application time had long is required. In this study. 6 middle periodic herbicides among sulfonylurea derivatives and 2 quinclorac mixture were selected and evaluated their weeding spectrums at different leaf stage of barnyardgrass in both soil application in flooding condition and foliage application in dry paddy field. The order of weeding spectrum in magnitude was as follows : bentazone+quinclorac WP> bentazone + quinclorac G>bensulfuronmethyl + quinclorac G>pyrazosulfuronethyl + quinclorac G> pyrazosulfuronethyl + Molinate G>bensulfuronmethyl + mefenacet + dymron G>bensulfuronmethyl + mefenacet G>bensulfuron methyl+benthiocarb G. The above results coincided with that of the survey. In conclusion, there is no proper substitute for quinclorac mixrure, which can control barnyardgrass at 3.0 leaf stage or even older. Therefore quinclorac should be supplied continuously to farmers in order to anchor direct rice seeding in Korea. Author suggested the followings to eastablish direct rice seeding technology effectively and quickly : 1) A tentatively named "The research committee for direct rice seeding" which was composed of farmers. researchers and goberment. should be eastablished to cooperate effectively. 2) Development of a pricise direct rice seeding machine for both dry and flooding paddy field. which is workable regardless of condition and varieties of seeds. 3) Study on protecting rice seed and seedling from sparrows. 4) Systematic studies of weed control techniques in direct rice seeding to standardize herbicide application. 5) Studies on farm-land reformation. techniques of precise land preparation. and direct rice seeding using an airplane.

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Antibacterial and Therapeutic Effects of Houttuynia cordata Ethanol extract for Murine Salmonellosis (어성초 ethanol 추출물의 마우스 살모넬라 감염증에 대한 항균 및 치료효과 규명)

  • Kim, Dong-Hyeok;Lim, Jung-Ju;Lee, Jin-Ju;Jung, Won-Chul;Shin, Hyeon-Jin;Lee, Hu-Jang;Kim, Gon-Sup;Kim, Suk
    • Korean Journal of Environmental Agriculture
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    • v.27 no.2
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    • pp.156-162
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    • 2008
  • Salmonellosis is a major bacterial zoonosis that causes a variety of disease syndromes, self-limited enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans. Recently, the emergence of multidrug resistant strains of Salmonella spp. causes more serious problems in environment and public health. The present study was investigated the antibacterial effect of Houttuynia cordata ethanol extract(HCEE) for murine salmonellosis. In the cytotoxic effect of HCEE on RAW 264.7 cells, there was no detectable effect with any concentrations between 25 and 100 ${\mu}g/ml$ after 8 h incubation. The bacteriocidal effect of HCEE was not showed on a Salmonella enterica serovar Typhimurium(S. typhimurium). HCEE makes morphological change of the RAW 264.7 cells, and there was significant decreased bacterial uptake and intracellular replication within Salmonella infected cells. And further nitric oxide(NO) production of Salmonella infected RAW 264.7 cells with HCEE was decreased comparing to RAW 264.7 cells without HCEE until 8 h post infection. Oral administration of HCEE showed a therapeutic effect for S. typhimurium infected BALB/c mice. The mortality of HCEE treated mouse was 80% until 12 days, while that of HCEE untreated mouse was 100 % until 8 days after lethal dose of S. typhimurium infection. These data suggested that HCEE has a potency treatment for intracellular replicative pathogen including salmonellosis, brucellosis, tuberculosis, listeriosis etc., and the application of HCEE makes new strategies for safety medicine development without antibiotic resistance bacterial appearance and residue problem in food and solves the public health problem from antibiotic mis- and over use.

Mammary Performance of First Lactation Bali Cows (Bibos banteng) Fed Grass-Legume Based Diets in Relation to the Role of Glucose

  • Sukarini, I.A.M.;Sastradipradja, Djokowoerjo;Nusada, N.;Mahardika, I.G.;Kiranadi, B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.5
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    • pp.615-623
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    • 2001
  • A study of mammary function in relation to glucose metabolism of first lactation Bali cows on grass-legume diets was carried out using 12 primiparous cows (initial BW $263.79{\pm}21.66kg$) for 16 weeks starting immediately post calving. The animals were randomly allocated into 4 dietary treatment groups R1, R2, R3 and R4, receiving from the last 2 months of pregnancy onwards, rations based on a mixture of locally available grass and legume feed ad libitum. On a DM basis R1 contained 70% elephant grass (PP, Penicetum purpureum) plus 30% Gliricidia sepia leaves (GS), R2 was 30% PP plus 25% GS supplemented with 55% Hibiscus tilliacius leaves (HT, defaunating effect), R3 and R4 were 22.5% PP+41.25% GS+11.25% HT+25% concentrate, with R4 supplemented with zinc-diacetate. TDN, CP and zinc contents of the diets were 58.2%, 12.05% and 18.3 mg/kg respectively for R1, 65.05%, 16.9% and 25.6 mg/kg respectively for R2, 66.03%, 16.71% and 29.02 mg/kg respectively for R3 and 66.03%, 16.71% and 60.47 mg/kg respectively for R4. Milk production and body weights were monitored, an energy and protein balance trial conducted, overall glucose kinetics parameters assessed, mammary blood flow (MBF) and metabolite arteriovenous differences (${\Delta}AVs$) measured to get uptake data and mammary performance relationships. Parameters of glucose kinetics at peak lactation or during dry condition were not affected by ration quality. Glucose pool size, space of distribution and flux increased by 61.77, 62.26 and 82.08%, respectively, during lactation compared to the dry period. Mean glucose flux of lactating Bali cows was $5.52mg/min.kgBW^{0.807}$ which resembles the range of values of temperate dairy cows. Calculation showed that glucose requirements for maintenance, milk lactose and fat-glycerol synthesis, and the formation of NADPH reached 461.69 g for a yield of 1 kg/d or equal to 320.62 mg/min, which was less than the average glucose flux of lactating Bali cows of 481.35 mg/min. Mammary blood flow (MBF) values ranged from 56 to 83 l/h for the different treatments and the ratio MBF per kg milk produced improved from av. 1540 l/kg for R1 to av. 967 l/kg for R4 treated cows. Mammary glucose uptake ranged from 6.27 to 12.03 g/h or 120 to 140 g/kg milk. Glucose uptake was mass-wise 2 to 4 times the amount secreted as lactose, which indicated values less than the calculated mammary glucose needs and that little lactose was synthesized. The excess glucose taken-up was used for other metabolic processes. Linear relationships between metabolite ${\Delta}AVs$ and arterial blood plasma concentration [A] showed that in Bali cows triglycerides (TG), phenylalanine (Phe) and tyrosine (Tyr) have high coefficients of determination, i.e. 0.77, 0.81 and 0.69, respectively. For glucose, the relationship is quadratic with an $R^2$ value of 0.49. It was concluded that lactose synthesis was inadequate, which led to a speculation that milk yield could be improved by increased lactose synthesis.

The nanoleakage patterns of experimental hydrophobic adhesives after load cycling (Load cycling에 따른 소수성 실험용 상아질 접착제의 nanoleakage 양상)

  • Sohn, Suh-Jin;Chang, Ju-Hae;Kang, Suk-Ho;Yoo, Hyun-Mi;Cho, Byeong-Hoon;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
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    • v.33 no.1
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    • pp.9-19
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    • 2008
  • The purpose of this study was: (1) to compare nanoleakage patterns of a conventional 3-step etch and rinse adhesive system and two experimental hydrophobic adhesive systems and (2) to investigate the change of the nanoleakage patterns after load cycling. Two kinds of hydrophobic experimental adhesives, ethanol containing adhesive (EA) and methanol containing adhesive (MA), were prepared. Thirty extracted human molars were embedded in resin blocks and occlusal thirds of the crowns were removed. The polished dentin surfaces were etched with a 35 % phosphoric acid etching gel and rinsed with water. Scotchbond Multi-Purpose (MP), EA and MA were used for bonding procedure. Z-250 composite resin was built-up on the adhesive-treated surfaces. Five teeth of each dentin adhesive group were subjected to mechanical load cycling. The teeth were sectioned into 2 mm thick slabs and then stained with 50 % ammoniacal silver nitrate. Ten specimens for each group were examined under scanning electron microscope in backscattering electron mode. All photographs were analyzed using image analysis software. Three regions of each specimen were used for evaluation of the silver uptake within the hybrid layer. The area of silver deposition was calculated and expressed in gray value. Data were statistically analyzed by two-way ANOVA and post-hoc testing of multiple comparisons was done with the Scheffe's test. Silver particles were observed in all the groups. However, silver particles were more sparsely distributed in the EA group and the MA group than in the MP group (p < .0001). There were no changes in nanoleakage patterns after load cycling.

Decision Making on the Non surgical, Surgical Treatment on Chronic Adult Periodontitis (만성 성인성 치주염 치료시 비외과적, 외과적 방법에 대한 의사결정)

  • Song, Si-Eun;Li, Seung-Won;Cho, Kyoo-Sung;Chai, Jung-Kiu;Kim, Chong-Kwan
    • Journal of Periodontal and Implant Science
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    • v.28 no.4
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    • pp.645-660
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    • 1998
  • The purpose of this study was to make and ascertain a decision making process on the base of patient-oriented utilitarianism in the treatment of patients of chronic adult periodontitis. Fifty subjects were chosen in Yonsei Dental hospital and the other fifty were chosen in Severance dental hospital according to the selection criteria. Fifty four patients agreed in this study. NS group(N=32) was treated with scaling and root planing without any surgical intervention, the other S group(N=22) done with flap operation. During the active treatment and healing time, all patients of both groups were educated about the importance of oral hygiene and controlled every visit to the hospital. When periodontal treatment needed according to the diagnostic results, some patients were subjected to professional tooth cleaning and scaling once every 3 months according to an individually designed oral hygienic protocol. Probing depth was recorded on baseline and 18 months after treatments. A questionnaire composed of 6 kinds(hygienic easiness, hypersensitivity, post treatment comfort, complication, functional comfort, compliance) of questions was delivered to each patient to obtain the subjective evaluation regarding the results of therapy. The decision tree for the treatment of adult periodontal disease was made on the result of 2 kinds of periodontal treatment and patient's ubjective evaluation. The optimal path was calculated by using the success rate of the results as the probability and utility according to relative value and the economic value in the insurance system. The success rate to achieve the diagnostic goal of periodontal treatment as the remaining pocket depth less than 3mm and without BOP was $0.83{\pm}0.12$ by non surgical treatment and $0.82{\pm}0.14$ by surgical treatment without any statistically significant difference. The moderate success rate of more than 4mm probing pocket depth were 0.17 together. The utilities of non-surgical treatment results were 100 for a result with less than 3mm probing pocket depth, 80 for the other results with more than 4mm probing pocket depth, 0 for the extraction. Those of surgical treatment results were the same except 75 for the results with more than 4mm. The pooling results of subjective evaluation by using a questionnaire were 60% for satisfaction level and 40% for no satisfaction level in the patient group receiving nonsurgical treatment and 33% and 67% in the other group receiving surgical treatment. The utilities for 4 satisfaction levels were 100, 75, 60, 50 on the base of that the patient would express the satisfaction level with normal distribution. The optimal path of periodontal treatment was rolled back by timing the utility on terminal node and the success rate, the distributed ratio of patient's satisfaction level. Both results of the calculation was non surgical treatment. Therefore, it can be said that non-surgical treatment may be the optimal path for this decision tree of treatment protocol if the goal of the periodontal treatment is to achieve the remaining probing pocket depth of less than 3mm for adult chronic periodontitis and if the utilitarian philosophy to maximise the expected utility for the patients is advocated.

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Systems for Production of Calves from Hanwoo(Korean Cattle) IVM/IVF/IVC Blastocyst II. Simple, Efficient and Successful Vitrification of Hanwoo Blastocyst (체외생산된 한우 배반포기배로부터 송아지 생산을 위한 체계 II. 한우 배반포기배를 간편하면서 효율적이고 성공적으로 유리화 동결하는 방법)

  • Kim, E.Y.;Kim, D.I.;Park, N.H.;Weon, Y.S.;Nam, H.K.;Lee, K.S.;Park, S.Y.;Yoon, S.H.;Park, S.P.;Chung, K.S.;Lim, J.H.
    • Korean Journal of Animal Reproduction
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    • v.23 no.4
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    • pp.281-291
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    • 1999
  • The objective of this study was to optimize the freezing/thawing method of in vitro produced Hanwoo blastocysts. Day 7 blastocysts after IVF were vitrified using EFS40 (40% ethylene glycol, 18% ficoll, 0.3 M sucrose and 10% FBS added m-DPBS) as a freezing solution and electron microscope (EM) grid (V-G) or straw (V-S) as an embryo container. In both method, freezing/thawing were treated by 2-step, treatment time was required in V-G method and V-S method, for 2 min / 3 min and 3.5 min / 10 min, respectively. Embryo survival was assessed as re-expanded and hatched rates at 24 h and 48 h after warming, respectively. The results obtained in these experiments were summarized as follows: when the effect of exposure in vitrification solution and chilling injury from freezing procedure on in vitro produced expanded blastocysts were examined, at 24 h after warming, embryo survival in exposure group (100.0%) was not different compared to that in control group (100.0%), although those results were significantly different with two vitrified groups (V-G: 87.8, V-S: 77.8%) (P<0.001). However, at 48 h after warming, hatched rates of V-G group (67.8%) were significantly higher than those of V-S group (53.3%) (P<0.05). In addition, this hatched rate in V-G group was not different with that in exposure group (73.3%). When the effects of embryo developmental stage (early, expanded and early hatching blastocysts) and embryo container (EM grid and straw) to the in vitro survival of vitrified-warmed day 7 Hanwoo blastocysts were simultaneously examined, fast developed embryos were indicated the better resistance to freezing than delayed developed one, irrespective of embryo containers (early; 57.1 & 24.4%, expanded; 84.7 & 60.6%, early hatching; 91.7 & 80.0%) (P<0.001). Especially, in expanded and early hatching blastocysts, embryo survival of V-G group (67.8, 95.0%) was significantly higher than those of V-S group (53.0, 65.0%) at 48 h post warming, respectively (P<0.05, P<0.001). Therefore, this study indicates that Hanwoo blastocysts can be cryopreserved more simple, efficient and successful by vitrification method using EM grid.

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Experimental Pathogenesis of Pullorum Disease with the Local Isolate of Salmonella enterica serovar. enterica subspecies Pullorum in Pullets in Bangladesh

  • Haider, M.G.;Chowdhury, E.H.;Khan, M.A.H.N.A.;Hossain, M.T.;Rahman, M.S.;Song, H.J.;Hossain, M.M.
    • Korean Journal of Poultry Science
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    • v.35 no.4
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    • pp.341-350
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    • 2009
  • The research work was carried out to study the pathogenesis covering the clinical signs, gross and histopathological lesions in different organs, and reisolation and identification of the organisms after experimental infection with the local isolate of Salmonella enterica serovar. enterica subspecies (S.) Pullorum at different time interval of the experiment during the period February 2006 to December 2006. One hundred pullets (seronegative to S. Pullorum of 12 weeks age were purchased and divided into 5 (A, B, C, D and E) groups and each group consisted of 20 birds. Four groups (A, B, C and D) were infected orally with a dose of $10^6\;CFU$, $10^7\;CFU$, $2{\times}10^7\;CFU$, $10^8\;CFU$ of S. Pullorum, respectively, and one group (E) was treated as uninfected control. The used methods were necropsy and histopathology, culture of bacteria, staining and biochemical test of Salmonella. Five birds from each group were randomly selected and sacrificed $1^{st}$ week, $2^{nd}$, $3^{rd}$ and $4^{th}$ weeks of post infection (PI). From all the groups, the bacteriological samples (crop, liver, lung, heart, spleen, bile duodenum, ceca and blood) were collected with pre enriched in buffered peptone water in sterile poly bags. Liver, lungs, heart, spleen, intestine, etc. were collected in 10% buffered-formalin for histopathological examination. No clinical signs, gross and histopathological lesions were found in control group and no S. Pullorum was reisolated. Clinical sign of experimentally infected with S. Pullorum in pullets were loss of appetite (100%), slight depression (75%), ruffled feathers (85%), diarrhea (60%) and loss of weight (100%) in chickens. The feed intake and body weight at different weeks after PI differed significantly (p<0.01) among the groups. Grossly, the highest recorded lesion was button-like ulcer in the ceca (80%) and the lowest was white nodules in lungs (1.25%). S. Pullorum were reisolated from crop (91.25%), liver (91.25%), lung (83.75%), heart (71.25%), spleen (87.75%), bile (33.25%), duodenum (92.50%), ceca (97.50%) and from different group of infection (61.25%). The highest microscopic findings were intestinal and cecal mucosa and submucosa exhibited infiltration of mononuclear cells and congestion (96.25%), and the lowest finding was nodule formation in the lungs (3.75%). The pattern of the disease production by local isolate of S. Pullorum in Bangladesh is almost similar with other isolates in different countries.

Clinical Characteristics of Influenza B Virus in Children and the Efficacy of Oseltamivir: Data from Two University Hospitals (소아에서 B형 인플루엔자 바이러스의 감염에서 oseltamivir 치료의 유용성: 2개 병원에서 조사된 환자들을 대상으로)

  • Youn, Song Ee;Chun, Ji Hye;Lee, Kyung Suk;Rha, Yeong Ho;Choi, Sun Hee
    • Pediatric Infection and Vaccine
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    • v.21 no.3
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    • pp.199-206
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    • 2014
  • Purpose: There has been little research regarding the effectiveness of oseltamivir for influenza B infections. We sought to identify the different clinical manifestations between patients treated with and without oseltamivir. Methods: We retrospectively studied the medical records of 72 inpatients or outpatients from two medical centers diagnosed with influenza B infections by either a rapid antigen test or multiplex reverse transcriptase PCR between January 2012 and July 2012. We compared gender, age, past medical history, admission period, total fever duration, fever duration after hospitalization, post-oseltamivir medication peak temperature, laboratory test, chest X-ray, antibiotic medication, and the presence of concomitant viral or bacterial infections. Results: The number of subjects in our study was 72 who were diagnosed with influenza B pneumonia, acute bronchitis, acute bronchiolitis, croup, and mean age was $3.6{\pm}2.8$ year old. The demographic characteristics and clinical manifestations of oseltamivir and the non-oseltamivir groups, including hospitalization period ($4.18{\pm}2.10$ vs $4.79{\pm}1.49$ days, P=.17) and total fever duration ($5.32{\pm}2.07$ vs $6.41{\pm}3.25$ days, P =.09), demonstrated no significant differences. Notably, the oseltamivir group did have significantly reduced usage of antibiotic treatment than the non-oseltamivir group (P=.04). When we limited our patient group to patients under the age of three, similar results were seen. The group prescribed oseltamivir within 48 hours of fever onset had less antibiotic usage, in addition to a shorter fever duration. Conclusion: Oseltamivir appeared to have no benefit in improving the clinical course. However, if it is prescribed within the first 48 hours of symptoms, it may be more effective.

Short-Term Result of Endovenous 980-nm Diode Laser Treatment in Varicose Vein of Looter Extremities (하지정맥류에서 정맥내 980-nm 다이오드 레이저 치료의 단기결과)

  • Lee Seock Yeol;Song In Hag;Lee Seung Jin;Park Hyung Joo;Lee Cheol Sae;Lee Kihl Rho
    • Journal of Chest Surgery
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    • v.38 no.8 s.253
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    • pp.557-563
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    • 2005
  • Background: Recently 980-nm diode laser endovenous treatment was introduced and used as a method of treatment for varicose vein in lower extremities. The advantages of endovenous laser treatment are good cosmetic effects without incision and avoidance of complications associated with surgery. Therefore, we performed an endovenous laser treatment using a 980-nm diode laser and observed the effects and the efficiency of treatment. Material and Method: From October, 2003 to March, 2004, 55 patients (84 limbs) underwent endovenous laser treatment with a 980-nm diode laser. The effects of treatment, complications and recurrences were reviewed. Result The mean age of patients was 47.2 years old and the number of men and women were 2f and 35. In a total of 84 limbs, postoperative complications were transient ecchymosis(84 cases), local paresthesia (24 cases), local skin discolorization (6 cases), minimal burn (3 cases), and post operative phlebitis (1 cases). Adjuvant sclerotherapy was performed in 27 limbs and it was performed in varicose veins missed at operation and varicose veins remaining after endovenous laser treatment. In a total of 56 patients, 2 patients $(3.57\%)$ had recurrences after endovenous laser treatment and were treated with phlebectomy. Conclusion: Our findings demonstrated that 980-nm endovenous laser treatment had good cosmetic results with acceptable complications. This study was based on short-term results and long term follow-up is necessary to evaluate the accurate effects of treatment and recurrence. We think that multimodality treatment with endovenous laser treatment including phlebectomy or transilluminated powered phlebectomy can help decreasing of recurrence especially in patients with tortuous varicose cluster.

The Effects of the Warm Ischemic Time, the Preserving Temperature and the Cryopreservation Solution on the Viability of Tracheas (온혈허혈시간과 냉동보존온도와 보존액 조성에 따른 기관의 생육성 비교)

  • Sa, Young-Jo;Park, Jae-Kil;Sim, Sung-Bo;Jin, Ung;Moon, Young-Kyu;Lee, Sun-Hee;Jo, Kuhn-Hyun
    • Journal of Chest Surgery
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    • v.42 no.3
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    • pp.283-291
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    • 2009
  • Background: Tracheal reconstruction after extended tracheal resection still remains as a major surgical challenge because good clinical outcomes are usually correlated with limited tracheal resection. Recent investigations with a using cryopreserved trachea for the reconstruction of a trachea have been carried out to overcome this problem. In this study, we analyzed viability of tracheas, which is an important determining factor for the success of transplanting a cryopreserved trachea and the development of post-transplantation tracheal stenosis, according to three different experimental factors: 1) the warm-ischemic time, 2) the cryopreservation solution and 3) the preserving temperature, to determine a better cryopreservation protocol and a better composition of the cryopreservation solution. Material and Method: Rats tracheas were harvested for different warm-ischemic times (0 hr, 12 hrs, 24 hrs). The tracheas were treated with recombinant insulin growth factor-1 (IGF) and they were stored at three different temperatures $(4^{\circ}C,\;-80^{\circ}C,\;-196^{\circ}C)$ for two weeks. After two weeks, we thawed the stored trachea and isolated the cells of the tracheas with using type II collagenase. We cultured the cells for seven days and then we compared the cellular viability by the MTT reduction assay. Result: Though cryopreservation is required to preserve a trachea for a longer time period, the viability of the tracheas stored at $-80^{\circ}C$ and $-196^{\circ}C$ was significantly reduced compared to that of the tracheas stored at $4^{\circ}C$. The viability of the tracheas with warm-ischemic times of 12 hrs and 24 hrs was also reduced in comparison to the tracheas with a warm-ischemic time of 0 hrs. Our data showed that the warm ischemic time and the parameters of crypreservation negatively affect on trachea viability. However, a cryopresrvation solution containing IGF-1 improved the cellular viability better than the existing cryopreservation solution. For the warm ischemic time group of a 0 hr, the addition of IGF-1 improved the viability of trachea at all the preserving temperatures. Conclusion: These experiments demonstrate that the viability of cryopreserved trachea can improved by modifying the components of the crypreservation solution with the addition of IGF-1 and reducing the warm-ischemic time.