• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.159-168
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• 2003

With microtiter plate, the assay method was developed for detecting the fungicidal activity of new compounds against spore germination, spore adhesion and mycelial growth of Colletotrichum sp. JC24 cal1Sing red pepper anthracnose. Also, the effects of some commercialized fungicides on fungal development like above mentioned were investigated by measuring the optical density of mycelia grown into wells of microtiter plate. For the standardization of assay method, some factors, such as the treatment of MTT and/or propanol, inodulum density and incubation period, affecting on mycelial optical density were investigated. For obtaining precise and consistent mycelial optical density, it was necessary the treatment of MTT for 12 hrs and propanol for 1 hr. inoculum density adjusted to $1\times10^5$ spores/mL and incubation period for 36 hrs at $25^{\circ}C$. For fungicidal activities, 6 protective fungicides, 6 ones inhibiting sterol biosynthesis, and one inhibiting respiration were used in this study. While mancozeb, chlorothalonil and dithianon among 6 protective fungicides inhibited strongly spore germination, adhesion, and mycelial growth at $6.25{\mu}g/mL$, propineb, iminoctadine and fluazinam inhibited intermediately spore germination and mycelial growth at $100{\mu}g/mL$. Washing above 3 fungicides with new PD broth, their activity against spore adhesion decreased. With hexaconazole, tebuconazole and myclobutanil, the tendency of the activity against fungal differentiation of the early infection stage was similar to the latter group of protective fungicides, showing the decrease of the inhibitory activity against spore adhesion by washing 2 hrs after incubation. However, kresoxim-methyl inhibited spore adhesion distinctly, depending on the applied concentrations. Based on these results, it might be able to assess the fungicidal activity of many compounds against spore germination, adhesion and mycelial growth by the use of microtiter plate in vitro. Using the assay developed in this report, it was possible to investigate the inhibitory activity of some commercialized fungicides, too.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.344-350
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• 2006

An Antiviral producing bacterial strain was isolated from ginseng root environment in Hongcheon, Kangwon province of Republic of Korea. Identification of this bacterial strain was performed by physiological and biochemical tests along with 16S rRNA analyses. The results revealed that the bacterium was closer to genus Serratia, which was named as Gsm01. The strain was grown in Mannitol-Glutamate-Yeast (MGY) broth for 48 h. The culture was centrifuged and the filtrate obtained was tested for its ability to control Cucumber mosaic virus strain Y (CMV-Y) in greenhouse and field experiments. In the green house experiments, CF was evaluated for its ability to protect local host, Chenopodium amaranticolor and systemic host of CMV, Nicotiana tabacum cv. Xanthi-nc. It was found that, CF treatment reduced viral infection by 98% in local host; C. amaranticolor. The N. tabacum cv. Xanthi-nc plants treated with CF did not show visible viral symptoms 15 days post inoculation (dpi) and remained symptomless throughout the periods of the study. To evaluate effectiveness of CF under field conditions, experiment was carried out in a polyvinyl house. It was observed that, 52% plants were protected from viral diseases compared to non-treated plants, increasing the crop yield. This is the first report showing antiviral activity of a Serratia spp. against CMV.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.45-50
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• 2001

In recent, non virus-induced mosaic symptoms(NVMS) on potato leaves were observed in the seed potato fields, and its incidence rate was $5{\sim}20%$ nationwide. It made difficult to rogue out virus-infected plants, and caused much arguments between seed potato production farmers and seed potato inspectors. The objectives of these experiments were to find out the causes of NVMS, and also to induce mosaic symptom(phytotoxicity) on potato plants by treatment of several herbicides. No significant correlations were found between incidence rates of NVMS and values from soil analyses; soil pH, soil EC, organic matter content, and contents of inorganic constituents($P_2O_5,\;NO_3$, Ca, Mg, K) in the soil around the potato planted. The examinations by ELISA, virus indicator plants, and TEM showed that NVMS on potato leaves was not caused by the viruses infection. But, the use of herbicides could induced the NVMS on potato leaves. The incidence rates of potato treated with pendimethalin linuron of 400 mL/10 a, pendimethalin of 200 mL/10 a, pendimethalin.oxadiazon of 300 mL/10 a, and control were 61.1%, 47.2%, 19.4%, and 1.4%, respectively. Based on these results, we confirmed that the treatment of pendimethalin alone and in mixture with other herbicides were the reason of NVMS on potato leaves. The yields among test plots were similar except dicamba treated plot, which decreased by about 23% compared to control plot. When their progenies harvested in 1999 were planted in the following season, no symptoms of mosaic were observed.

• Journal of the Society of Disaster Information
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• v.13 no.4
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• pp.442-454
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• 2017

Biological weapon is manipulated and produced from microorganisms such as bacteria, virus, rickettsia, fungi etc. It is classified as one of the Weapons of Mass Destruction (WMD) along with chemical weapon and radiological weapon. Biological weapon has a number of operational advantages over the other WMDs including ease of development and production, low cost and possibility of covert dissemination. In this study we analyze the history of biological weapon's development and the existing biological threats. Then, we predict the social impact of biological attack based on the physical properties of biological agent and infection mechanisms. By analyzing the recognition, dispersion pattern of agents, characteristics of the diseases in the biological weapon related historical events such as Sverdlovsk anthrax accident, 2001 anthrax attack, we found out some of the facts that biological attack would not likely to be recognized rapidly, produce large number of the exposed, increase number of paients who suffed from severe respiratory illness. It would lead the public health and medical service providers to be struggled with hugh burden. Base on the facts that we found from this case study, we suggested the main capabilities of public health required to respond to bioterrorism event efficiently. Syndromic surveillance and other reporting system need to be operated effeciently so that any suspicious event should be detected promptly. the pathogen which suspected to be used should be identified through laboratory diagnostic system. It is critical for the public health agency to define potentially exposed population under close cooperation with law enforcement agencies. Lastly, massive prophylaxis should be provided rapidly to the people at need by operating human and material resources effeciently. If those capacities of public health are consistantly fortified we would be able to deal with threat of bioterrorism successfully.

• Journal of Chest Surgery
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• v.38 no.2 s.247
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• pp.123-131
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• 2005

Background: The number of elderly patients undergoing coronary artery bypass grafting (CABG) is increasing. Elderly patients are at increased risk for a variety of perioperative complications and mortality. We identified determinants of operative complications and mortality in elderly patients undergoing CABG. Material and Method: Between January 1995 and July 2003, 91 patients older than 75 years underwent isolated CABG at Asan Medical Center. There were 67 men and 24 women with mean age of $77.0\pm2.4$ years. Thirty clinical or hemodynamic variables hypothesized as predictors of operative mortality were evaluated. Result: CABG was performed under emergency conditions in 5 patients. The internal thoracic artery was used in 85 patients and 10 patients received both internal thoracic arteries. The mean number of distal anastomosis was 3.7 per patient. Operative mortality was $3.3\%$. Twenty-two patients had at least one major postoperative complication. Low cardiac output syndrome was the most common complication, followed by reoperation for bleeding, pulmonary dysfunction, perioperative myocardial infarction, stroke, acute renal failure, ventricular arrhythmia, upper gastrointestinal bleeding, infection, and delayed sternal closure. None were the predictors of mortality. Renal failure, peripheral vascular disease, emergency operation, recent myocardial infarction, congestive heart failure, New York Heart Association (HYHA) class III or IV, Canadian Cardiovascular Society (CCS) angina scale III or IV, and low left ventricle ejection fraction below $40\%$ were univariate predictors of overall complications. Actuarial probability of survival was $94.9\%,\;89.8\%,\;and\;83.5\%$ at postoperative 1, 3 and 5 years respectively. During the follow-up period $93.3\%$ of patients were in NYHA class I, or II and $91.1\%$ were free from angina. Conclusion: Although operative complication is increased, CABG can be performed with an acceptable operative mortality and excellent late results in patients older than 75 years.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.454-464
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• 2001

Background: It has been recognized that systemic inflammatory reaction and oxygen free radical formed by activated leukocyte in the procedure of cardiopulmonary bypass(CPB) frequently produce postoperative cardiac and pulmonary dysfunction. The purpose of this study was to evaluate the efficacy of leukocyte-depleting filters in the cardiopulmonary bypass circuit for patients undergoing open heart surgery(OHS). Material and method: The study involved 15 patients who underwent OHS with a Leukoguard-6 leukocyte filter placed in the arterial limbs of the bypass circuit(filter group, n=15) and 15 patients who did not have the filter(control group, n=15). We analyzed the differences between the groups in intraoperative changes of peripheral blood leukocyte and platelet counts, pre- and postbypass changes of malondialdehyde(MDA), troponin-T(TnT), 5'-nucleotidase(5'-NT) in coronary sinus blood, spontaneous recovery rate of heart beat after CPB, pre-and postoperative cardiac index(Cl) and pulmonary vascular resistance(PVR), and the amounts of postoperative bleeding and sternal wound complication. Result: During CPB, total leukocyte count of the filter group(9,567$\pm$ 842/㎣) was significantly less than that of the control group(13,573+1,167/㎣) (p<0.01), but there was no significant difference in platelet count between the groups. Postoperative levels of MDA(3.78+0.32 $\mu$mol/L vs 5.86+0.65 $\mu$mo1/L, p<0.01), TnT(0.40$\pm$0.04 ng/mL vs 0.59$\pm$0.08 ng/mL, p<0.05) and 5'-NT(3.88$\pm$0.61 U/L vs 5.80$\pm$0.90 U/L, p<0.05) were all significantly lower in the filter group than the control group. Postoperative Cl was higher in the filter group than the control group(3.26$\pm$0.18 L/$m^2$min vs 2.75$\pm$0.17 L/$m^2$/min, p=0.05). PVR of the filter group was lower than that of the control group(65.87$\pm$7.59 dyne/sec/cm$^{5}$ vs 110.80+12.22 dyne/sec/cm$^{5}$ , p<0.01). Spontaneous recovery rate of heart beat in the filter group was higher than that in the control group(12 patients vs 8 patients, p<0.05). Postoperative wound infection occurred in one case in the filter group and 4 case in the control group(p<0.05). Postoperative 24 hour blood loss of the filter group was more than that of the control group (614$\pm$107 mL vs 380+71 mL, p=0.05).

• Journal of Chest Surgery
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• v.29 no.12
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• pp.1323-1328
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• 1996

The obstructive diseases involving the left main coronary artery(LMCA) are serious. Surgical treatment is generally regarded as much more effective than medical therapy in terms of long-term survival and relief of symptoms. This study represents an attempt to present an analysis of early surgical results in 21 cases conducted at Chonnam University Hospital between October 1992 And August 1995. The subject. 12 males and 9 female, ranged in age from 25 to 67 years with a mean age of 49.3${\pm}$12.5 years. As for indications for operation, unstable angina was reported on 66.7% of the subjects, while stable angina and acute myocardial infarction in 4 and 3 cases, respectively. There were also 2 cases of Takayasu's aortitis and 1 case of failed percutaneous translumlnal coronary angioplasty(PTCA). Eleven subjects had isolated LMCA diseases compared to 10 subjects with associated LMCA diseases. Of the patients with ass;3ciated LMCA diseases, 4 subjects had single coronary artery disease, 3 had double coronary artery disease, remaining 3 suffered from triple coronary artery disease. As for the group with isolated LMCA disease, ostidl angioplasty llsing autopericardium was conducted with 5 subjects. The remaining subjects with the isolated diseases and all of the patients with associated LMCA disease underwent aortocoronary bypass grafts. The left internal mammary artery was used in all patients and the average number of anastomoses was 3.13 ${\pm}$0.93. One subject died of low cardiac output syndrome at the second postoperative day. There were 5 instances of postoperative complication including reoperation for bleeding in two patients, wound infection in two, and arrhythmia in one. Follow-up coronary angiogram were conducted with eights patients, including five patients who underwent ostial angioplasty. In these cases, the patients showed surf. ficient enlargement of the left coronary ostium and the grafted vessels kept their patency. In our experience, surgical treatment of the LMCA diseases has not shown a higher rAte of operative mortAlity or morbidity than other obstructive coronary artery diseases. To patients with ostial stenosis, which is frequently observed among young female, angioplasly utilizing autopericardium seems to be a desirable choice considering the cosmetic effect, chances of reoperation and hemodynamic characteristics.

• Journal of Chest Surgery
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• v.29 no.11
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• pp.1218-1222
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• 1996

The reported incidence of postcardiotomy cardiogenic shock not responding to conventional therapy is still 0.1 to 0.8%. For this group of patients, more aggressive form of circulatory support must be employed. Centrifugal pumps are a ventricular assist device most commonly used on this purpose, due to low cost and easy availability. Currently, however, clinical experience of centrifugal pumps as a ventricular assist device is rarely reported in Korea. From January 1992 to January 1996, 2986 patients underwent cardiac operations on cardiopulmonary bypass at Seoul National University Hospital. Refractory postcardiotomy cardiac failure requring ventricular support with a Biomedicus centrifugal pump developed in ten of these patients. There were eight men and two women, ranged in age from nine years to 77 years with a mean of 50$\pm$20 years. The primary surgical procedures consisted of isolated coronary revascularization in four patients, combined coronary revascularization and aortic valve replacement in two, aortic dissection repair in two, pulmonary embolectomy in one, and heart transplantation in one. Of the ten patients, five had left ventricular assistance, one had right ventricular assistance, and four had biventricular assistance. Duration of ventricular assistance ranged from 24 to 175 hours, with a mean of 76$\pm$51 hours. Seven patients were weaned from ventricular assistance, and four of them discharged. The causes of death for nonsurvivors were progressive cardiac failure in two patients and multiorgan failure, intractable ventricular fibrillation, irreversible brain injury, and mechanical problem, respectively, in the other four. Survival was not predicted by time on cardiopulmonary bypass, aortic cross-clamp time, or duration of ventricular support. Major complications included bleeding(7), renal failure(6), infection(3) and neurologic complication(2). These results indicate that a centrifugal pump can provide reasonably satisfactory short-term circulatory support.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.1
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• pp.54-63
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• 1994

Runner-derived(Expt.1) and tissue culture-derived strawbeery plantlets(Expt. 2) were grown in pots under greenhouse condition and inoculated with inocula of the vesicular-arbuscular mycorrhizal(VAM) fungi isolated from a field strawberry plants. Total biomass of mycorrhizal strawberry plants was significantly increased. There was a similar tendency in the number of cluster and flower at 20 weeks after inoculation, and VAM fungi inoculation positively influenced the leaf number, leaf length, leaf width and petiole length of strawberry plants in all investigated times. However, no difference was in the flowering time of strawberry plants. Leaf margin of non-inoculated strawberry plantlets turned into raddish brown(7.5R 4/8) from around 4 weeks after habituation. Inoculation of VAM fungi at the time of habituation was much more effective in stimulating plant growth. VA mycorrhizal dependency were 162.7 % in the runner-derived strawberry plants, Dependency with pre-and post-habituated incoulation in tissue culture-derived plants was respective 116.4% and 106.0%. The levels of mycorrhizal colonization were increased with plant growth and infection rates by endophytes at harvest time were 47.5% in Expt. 1, 56.4% in Expt. 2, respectively. Contents of phosphorus, potassium and calcium in mycorrhizal strawberry plants at harvest time were higher than non-mycorrhizal ones however, magnesium concentration was decreased. These experiments demonstrated that VAM fungi could be introduced into nursery stages of strawberry plantlets including the temporary planting period to improve growth and plant nutrients uptake by mycorrhizal plants.

• Clinical and Experimental Pediatrics
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• v.49 no.7
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• pp.777-783
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• 2006

Purpose : Urinary tract infection(UTI) is one of the most frequent infections in children. E. coli is the most frequent etiological micropathogen in pediatric community UTI, and E. coli has developed resistance to many antibiotics, highlighting the need for regular surveys of this organism resistant patterns in the community. The aim of this study was to determine the oral antibiotic susceptibility patterns of E. coli, isolated from pediatric patients with uncomplicated community acquired UTI. Methods : E. coli isolates, obtained from pediatric patients with uncomplicated community acquired UTI between October in 2004 to September in 2005. And minimal inhibitory concentrations(MICs) of oral aminopenicillins and beta-lactamase inhibnitors(ampicillin, amoxacillin, ampicillin-sulbactam), oral cephalosporins(cefaclor, cefixime) and sulfa drug(trimethoprime-sulfamethoxazole) were performed according to the National Committee for Clinical Laboratory Standards(NCCLS) guide line. Results : Total 211 organisms were isolated from pediatric out-patients with community UTI. E. coli was the most common organism(89 percent), followed by E. fecalis, Proteus species, S. aureus, M. morganii, and P. aeruginosa. The resistant rates of aminopenicillins and beta-lactamase inhibitors, cefaclor and sulfa drug to E. coli were very high. But, the resistant rate of cefixime was markedly low, and ESBL strains were isolated with small rates. Conclusion : Our study results suggest that aminopenicillins, cefaclor and sulfa drug may not be useful as first line empirical antibiotics to treat pediatric patients with community UTI in Korea. But, 3rd generation cephalosporin such as cefixime can be used as effective second line antibiotics after primary treatment failure, also may be useful as an empirical first line antibiotic. Finally, we conclude that a continuous surveillance study to monitor susceptibility patterns of E. coli in community UTI will be needed for the standard guide lines of empirical oral antibiotic treatment.