• Radiation Oncology Journal
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• v.18 no.4
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• pp.293-299
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• 2000

Purpose :We conducted a prospective non-randomized clinical study to evaluate the efficacy and toxic of the preoperative concurrent chemoradiotherapy for locally advanced unresectable rectal cancer. Materials and Methods: Between January 1995 and June 1998, 37 conecutive patients with locally unresectable advanced rectal cancer were entered into the study. With 3- or 4- fields technique, a total of 45 Gy radiation was delivered on whole pelvis, followed by 5.4 Gy boost to the primary tumor in some cases. Chemotherapy was done at the first and fifth week of radiation with bolus i.v. 5-Fluorouracil (FU) 370$\~$450 mg/m$^{2}$, days 1$\~$5, plus Leucovorin 20 mg/m$^{2}$, days 1$\~$5. OF 37 patients, 6 patients did not receive all planned treatment course (refusal in 4, disease progression in 1, metastasis to lung in 1). Surgical resection was undergone 4$\~$6 weeks after preoperative concurrent chemoradiotherapy. Results :Complete resection rate with negative margins was 94$\%$ (29/31). Complete response was seen in 7 patients (23$\%$) clinically and 2 patients (6$\%$) pathologically. Down staging of tumor occured in 21 patients (68$\%$). Treatment related toxicity was minimal except grade III & IV leukopenia in 2 patients, respectively. Conclusion : Preoperative concurrent chemoradiotherapy in locally advanced rectal cancer was effective in inducing down staging and complete resection rate. Treatment related toxicity was minimal. Further follow up is on-going to determine long term survival following this treatment.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.166-174
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• 2003

Microcystin produced by cyanobacteria in surface waters, such as eutrophic lake and river, is a kind of serious environmental problems due to its toxicity to human and wild animals. Microcystin is synthesized nonribosomally by the large modular multi-functional enzyme complex known as microcystin synthetase encoded by the mcy gene cluster. Amplification of mcy genes by PCR from cultures and environmental samples is a simple and efficient method to detect the toxigenic Microcystis. In order to evaluate primers designed to detect toxic microcystin-producing strains, 17 cyanobacterial strains and 20 environmental samples were examined by PCR with 7 pairs of primers. Some microcystin-producing cyanobacteria were not detected with FAA-RAA, TOX4F-TOX4R and FP-RP primers. The fragment of unexpected size was amplified with NSZW2-NSZW1 primers in Microcystis strains isolated from the lakes in Korea. TOX1P-TOX1F primers failed in amplification of toxin-producing strains. Only MSF-MSR and TOX2P- TOX2F primers amplified the fragments of mcy genes from 11 strains of microcystin-producing Microcystis. The water samples taken from 20 lakes in Korea were analyzed by PCR using each of the primers. In all the water samples, cyanobacteria capable of producing microcystin were detected by the PCR with TOX2P-TOX2F primers. These results indicate that TOX2P-TOX2F primers are better than the other primers for detection of microcystin-producing Microcystis strains in Korea. The nucleotide sequences of mcy gene in Microcystis aeruginosa NIER10010 suggest genetic diversity of Korean isolates.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.350-356
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• 2011

Environment-friendly agro-materials tend to be preferred to chemical insecticides recently. For this reason, many studies were conducted to develop environment-friendly insecticides containing natural materials. The purpose of this study was to assess ecotoxicity for 5 plant essential oils (Thyme white, Clove bud, Cassia, Lavender, Lemon eucalyptus) expected to prevent from pests and be used for agro-materials. Target species used to assess acute toxicity were aquatic invertebrate (Daphina magna), fish (Oryzias latipes), honeybee (Apis mellifera L.) and earthworm (Eisenia fetida). The EC50 value, toxicological responses of thyme white, clove bud, and cassia to Daphina magna were 2.5, 2.8, and $6.9mg\;L^{-1}$ respectively and these values were moderately toxic according to standard of USEPA. $EC_{50}$ of Lavender and lemon eucalyptus were >$10mg\;L^{-1}$ then they were considered as slightly toxicity. In case of acute toxicity test to fish, $LC_{50}$ of thyme white and cassia were 6.7 and $7.5mg\;L^{-1}$ each other. The other plant essential oils indicated $LC_{50}$ >$10mg\;L^{-1}$. Acute contact and oral toxicity test to Honeybee were conducted. As a result, $LD_{50}$ of all essential oils were >$100{\mu}g$ a.i. $bee^{-1}$ in both of tests. In case of acute toxicity test to earthworm, $LC_{50}$ of thyme white, clove bud, cassia, lavender, and lemon eucalyptus were 149, 230, 743, 234, and $635mg\;kg^{-1}$, respectively. In conclusion, if the safety for earthworm is confirmed, 5 plant essential oils are expected to be use for environment-friendly insecticide materials with low risk against ecosystem and contribute to developing environment-friendly agro-materials.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.134-141
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• 2005

To characterize genotypic and phenotypic traits of Staphylococcus aureus isolates (n = 86) from lettuces and raw milk, major virulence-associated genes and antibiotic susceptibility were detected using PCR-based methods and disk diffusion method, respectively. All isolates possessed coagulase gene and showed five polymorphism types [500 bp (2.4%), 580 bp (17.4%), 660 bp (61.6%), 740 bp (17.4%), and 820 bp (1.2%)] due to variable numbers of tandem repeats present within the gene. Two or three different loci of hemolysin gene family were dominant in isolates, 47 of which (55%) possessed combination of hla/hld/hlg-2 genes as the most prevalent types. Among enterotoxin-encoding genes, sea was detected from 32 isolates (37%), sed from 1 isolate (1%), and sea and sed genes were co-detected from 4 isolates (5%), whereas seb, sec, and tsst-1 genes were not detected. All isolates were susceptible to ciprofloxacin, trimethoprim/sulfamethoxazole, oxacillin, and vancomycin, 85 isolates (99%) to penicillin G, 54 isolates (63%) to chloramphenicol, 51 isolates (59%) to erythromycin, and 7 isolates (8%) to clindamycin. Among resistant isolates, seven displayed multiantibiotic-resistance against two different antibiotics.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.329-339
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• 1996

This study is to investigate the effect of mycorrhizal development, growth, nutrient absorption of P. thunbergii seedlings inoculated with Pisolithus tinctorius(Pt. KJ-1) in relation to toxic materials in soil. The concentrations on copper solution applied to the soils were 0, 40, 120, 260, 430ppm. The results are summarized as follows : 1. The germination of P. thunbergii with Pt. increased greater than without ectomycorrhizal fungi. Mycorrhizal development showed a significant decreasing trend at high concentration, and tolerant Cu test with Pt. in agar plate media showed a decreasing trend at a high level. 2. P. thunbergii seedlings inoculated with Pt. showed that the shoot length was significantly promoted at 40, 120ppm copper levels, and that of noninoculated seedlings had the lowest effect in 430ppm copper level. 3. The outer shape of ectomycorrhizal root tips after inoculating Pt. on P. thunbergii seedlings appeared as a monopodial type, a fern-like type, and a cluster-like type at 0ppm, 40ppm levels, but only monopodial type came out at 260ppm, 430ppm copper levels. 4. Root length, no. of juvenile leaves, total length of juvenile leaves, total dry weight, no. of needles and total length of needles of P. thunbergii with Pt. increased greater than those of noninoculated seedling. Growth response of P. thunbergii seedling inoculated with Pt. increased significantly at 40ppm, 120ppm Cu levels. 5. As a result of analysis of growth medium, pH, Na, CEC increased at higher Cu level, and total nitrogen, organic matters, available phosphorous, K, Ca and Mg decreased at 40ppm, 120ppm Cu levels. As a result of an analysis about a copper within soils, it appeared having high Cu-concentration at 0ppm level of an inoculated Pt. and high Cu-concentration in noninoculated Pt. than in inoculated Pt. at higher level. 6. As a result of an analysis of shoot, N, P, and K-concentration were higher in noninoculated seedlings than in inoculated seedlings, and Cu-concentration was higher in inoculated seedlings than in noninoculated seedlings. The analysis of root resulted in a high N-concentration at 40ppm, 120ppm levels, in a high P-concentration in inoculated seedlings and in a high Cu-concentration in noninoculated seedlings. Cu-concentration was significantly higher at root than at shoot.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.2
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• pp.111-115
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• 2007

It is inevitable to use germicidal agents like parabens, imidazolidinyl urea, phenoxyethanol and chlorphenesin to preserve the cosmetics. Although effective in reducing microblological contamination, chemical preservatives are irritative, allergenic and even toxic to human skin. So it is needed to decrease or eliminate usage of preservatives in cosmetic products Glycerin, butylene glycol (BG), prorylene glycol (PG), and dipropylene glycol (DPG) are widely used in cosmetics as skin conditioning agent or solvents. At high concentrations, they have antimicrobial activities, but deteriorate product quality like sensory feeling or safety. The purpose of study is to evaluate the effects of polyols on antimicrobial and preservative efficacy and confirm whether using adjusted polyols can decrease the contents of preservatives without deterioration of the quality of cosmetics. Effects of common polyols on antimicrobial activities of general preservatives were measured. BG and PG significantly (p < 0.05) increased activities of preservatives, but glycerin influenced little. It was inferred from the regression analysis of the results with S. aureus that adding 1% of PG increased activities of preservatives up to $2.1{\sim}8.4 %$ and BG improved activities of preservatives up to $1.8{\sim}8.4 %$. The challenge test results for oil in water lotions and creams showed that BG and PG improved the efficacy of preservative systems up to 40 % at a range of $5.5{\sim}9.9 %$, but glycerin had little effect on it. The measured rates of improvement were analogous to the inferences from regression analysis. It can be concluded that is possible to reduce total chemical preservatives up to 40 %, consequently improve the safety and sensory quality of cosmetics with the precision control of polyols. Added to that, using this paradigm, low preservative contents, praraben-free system, and even preservative-free systems can be expected in the near future.

• Korean journal of applied entomology
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• v.51 no.1
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• pp.47-58
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• 2012

Effect of a new crop protectant 'Bt-Plus' on natural enemies was analyzed in this study. Tested natural enemies included two parasitic species of $Aphidius$ $colemani$ and $Eretmocerus$ $eremicus$, and four predatory species of $Harmonia$ $axyridis$, $Orius$ $laevigatus$, $Amblyseius$ $swirskii$, and $Phytoseiulus$ $persimilis$. 'Bt-Plus' was formulated by combination of three entomopathogenic bacteria ($Xenorhabdus$ $nematophila$ (Xn), $Photorhabdus$ $temperata$ subsp. $temperata$ (Ptt), $Bacillus$ $thuringiensis$ (Bt)) and bacterial metabolite (BM). All three types of 'Bt-Plus' showed significantly higher toxicities against fourth instar $Plutella$ $xylostella$ larvae than Bt single treatment. Two types of bacterial mixtures ('Xn+Bt' and 'Ptt+Bt') showed little toxicity to all natural enemies in both contact and oral feeding assays. However, 'BM+Bt' showed significant toxicities especially to two predatory mites of $A.$ $swirskii$ and $P.$ $persimilis$. The acaricidal effects of different bacterial metabolites were evaluated against two spotted spider mite, $Tetranychus$ $urticae$. All six BM chemicals showed significant acaricidal effects. The BM mixture used to prepare 'Bt-Plus' showed a high acaricidal activity with a median lethal concentration at 218.7 ppm (95% confidence interval: 163.2 - 262.3). These toxic effects of bacterial metabolites were also proved by cytotoxicity test against Sf9 cells. Especially, benzylideneacetone, which was used as a main ingredient of 'BM+Bt', showed high cytotoxicity at its low micromolar concentration.

• Journal of agricultural medicine and community health
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• v.23 no.2
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• pp.305-310
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• 1998

The usage or agricultural chemicals is on the increasing tendency. Methyl bromide and organophosphate are the most widely used toxic agricultural chemicals in Korea. We try to set up the methods to detect the accumulation of these chemicals in Korean farmers. Blood samples were collected for 121 farmers of slack's season in February 1998. And survey about arable acreage and usage of the gloves and masks was also performed. Serum cholinesterase activities and bromide concentrations were measured with gold chloride method and colorimetric method. The reference ranges of serum cholinesterase activity and bromide concentration were 1.6~15.9 U/mL and below $72.9{\mu}g/mL$. Serum bromide concentrations of farmers and normal controls showed no differences. Serum cholinesterase activities of farmers were significantly higher than those of normal controls. According to the arable acreages and usage of the gloves and masks, serum bromide concentrations and cholinesterase activities showed no differences. In conclusion, serum cholinesterase activities and bromide concentrations showed no differences between farmers of slack's season and normal controls.

• Tuberculosis and Respiratory Diseases
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• v.41 no.3
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• pp.222-230
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• 1994

Background: Paraquat, a widely used herbicide, is extremely toxic, causing multiple organ failure in humans. Paraquat especially leads to irreversible progressive pulmonary fibrosis, which is related to oxygen free radicals. However, its biochemical mechanism is not clear. Natural mechanisms that prevent damage from oxygen free radicals include changes in glutathione level, G6PDH, superoxide dismutase(SOD), catalase, and glutathione peroxidase. The authors think catalase is closely related to paraquat toxicity in the lungs Method: The effects of 3-amino-1,2,4-triazole(aminotriazole), a catalase inhibitor, on mice administered with paraquat were investigated. We studied the effects of aminotriazole on the survival of mice administered with paraquat, by comparing life spans between the group to which paraquat had been administered and the group to which a combination of paraquat and aminotriazole had been administered. We measured glutathion level, glucose 6-phosphate dehydrogenase(G6PDH), superoxide dismutase(SOD), catalase, and glutathione peroxidase(GPx) in the lung tissue of 4 groups of mice: the control group, group A(aminotriazole injected), group B(paraquat administered), group C(paraquat and aminotriazole administered). Results: The mortality of mice administered with paraquat which were treated with aminotriazole was significantly increased compared with those of mice not treated with aminotriazole. Glutathione level in group B was decreased by 20%, a significant decrease compared with the control group. However, this level was not changed by the administration of aminotriazole(group C). The activity of G6PDH in all groups was not significantly changed compared with the control group. The activities of SOD, catalase, and glutathione peroxidase(GPx) in the lung tissue were significantly decreased by paraquat administration(group B); catalase showed the largest decrease. Catalase and GPX were significantly decreased by aminotriazole treatment in mice administered with paraquat but change in SOD activity was not significant(group C). Conclusion: Decrease in catalase activity by paraquat suggests that paraquat toxicity in the lungs is closely related to catalase activity. Paraquat toxicity in mice is enhanced by aminotriazole administration, and its result is related to the decrease of catalase activity rather than glutathione level in the lungs. Production of hydroxyl radicals, the most reactive oxygen metabolite, is accelerated due to increased hydrogen peroxide by catalase inhibition and the lung damage probably results from nonspecific tissue injury of hydroxyl radicals.

• Food Science and Preservation
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• v.24 no.8
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• pp.1168-1179
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• 2017

In this study, we tried to screen the Bacillus strain having safety probability by isolation of strains from traditional fermented food, measurement of probiotic properties, and the fermentative characteristics of Cheonggukjang. We isolated 400 Bacillus-like isolates from traditional fermented foods. Selected strains examined on the prevalent characteristic such as extracellular enzyme and antibacterial activities, and their safety probability was confirmed by biogenic amine productivity, hemolytic, and harmful substances and enzyme productivity. We selected the 5 strains by analysis of biogenic amine, antibacterial and B. cereus toxic associated gene. Five selected strains were examined on cell surface hydrophobicity, and bile and acid tolerance, and we selected the SRCM100730 as the final strain. SRCM100730 was confirmed B. amyloliquefaciens by 16S rRNA sequencing, and named the B. amyloloquefaciens SRCM100730 (KCCM11966P). Finally, we manufactured Cheonggukjang using SRCM100730 for confirmation of fermentation properties. Manufactured Cheonggukjang did not contain B. cereus, and showed that ${\gamma}$-PGA and extracellular enzyme activities were superior to commercial Chunggukjang. Amino nitrogen content was 544.02 mg% and 26 free amino acid were detected, and the bitterness-related amino acid content was lower than commercial Cheonggukjang. Especially, the amount of GABA was 3 fold higher than commercial Cheonggukjang. These results suggest that SRCM100730 have high availability in commercial probiotics market and fermented food industry.