• 한국데이터정보과학회:학술대회논문집
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• 2005.10a
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• pp.47-48
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• 2005

Multidimensional scaling is a multivariate technique for constructing a configuration of n points in Euclidean space using information about the distances between the objects. This can be done by the singular value decomposition of the data matrix. But it is known that the singular value decomposition is not resistant. In this study, we provide a resistant version of the multidimensional scaling.

• Animal Bioscience
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• v.34 no.2
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• pp.276-284
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• 2021

Objective: The objective of this study was to determine whether a dietary vitamin E (VE) supplement could alleviate any detrimental effects of aged corn on lipid metabolism and antioxidant status in laying hens. Methods: The experiment consisted of a 2×3 factorial design with two corn types (normal corn and aged corn (stored for 4 yr) and three concentrations of VE (0, 20, and 100 IU/kg). A total of 216 Lohmann laying hens (50 wk of age) were randomly allocated into six treatment diets for 12 wk. Each treatment had 6 replicates of 6 hens per replicate. Results: The results show that aged corn significantly decreased the content of low-density lipoprotein cholesterol (p<0.05), and reduced chemokine-like receptor 1 (CMKLR1) mRNA expression (p<0.05) in the liver compared to controls. Diet with VE did not alter the content of crude fat and cholesterol (p>0.05), or acetyl-CoA carboxylase, lipoprotein lipase, fatty acid synthase or CMKLR1 mRNA expression (p>0.05) in the liver among treatment groups. Aged corn significantly increased the content of malondialdehyde (MDA) (p<0.05) and decreased superoxide dismutase (SOD) activity (p<0.05) in the liver. The VE increased the content of MDA (p<0.05) but decreased glutathione peroxidase (GSH-Px) activity in serum (p<0.01) and in the ovaries (p<0.05). Adding VE at 20 and 100 IU/kg significantly increased GSH-Px activity (p<0.05) in liver and in serum (p<0.01), 100 IU/kg VE significantly increased SOD activity (p<0.05) in serum. Aged corn had no significant effects on GSH-Px mRNA or SOD mRNA expression (p<0.01) in the liver and ovaries. Addition of 100 IU/kg VE could significantly increase SOD mRNA expression (p<0.01) in the liver and ovary. Conclusion: Aged corn affected lipid metabolism and decreased the antioxidant function of laying hens. Dietary VE supplementation was unable to counteract the negative effects of aged corn on lipid metabolism. However, addition of 100 IU/kg VE prevented aged corninduced lipid peroxidation in the organs of laying hens.

• The Plant Pathology Journal
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• v.17 no.4
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• pp.227-230
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• 2001

Bioassay techniques using young leaves and roots were developed to screen resistance of Atractylis spp. against Phytophthora drechsleri. Among 638 plants collected from various regions of Korea from 1994 to 1996, 67 were pre-screened in fields naturally infested with P. drechsleri, which is the causal pathogen of rhizome rot of Atractylis. Among the pre-screened sources, 18 (ca. 26.8%) were highly resistant to the pathogen in leaf inoculation. In the root inoculation test, abundant sporangia were formed in susceptible plant roots, while only a few or no sporangia were produced on the roots which were found resistant in the leaf inoculation test. Among the selected resistant plants, A. japonica 96066 and 96104 were used to cross with another species, A. macrocephala 96362 that showed high yield with good quality of rhizome but susceptible to the pathogen. The F$_1$hybrids designated as HA03 turned out to be resistant to the pathogen, indicating that resistant gene(s) was inherited. Among intra-species hybrids of A. japonica, HA07 and HA09 were resistant to the pathogen in leaf inoculation and moderate in root inoculation. However, HA08 was susceptible in both inoculation tests. This result suggests that the parent material might be genetically heterogeneous. Further genetic study should be carried out to verify this phenomenon.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.199-206
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• 2008

Four hundred and thirteen oxytetracycline-resistant bacteria were recovered from six freshwater giant prawn farms with a history of oxytetracycline use. Most oxytetracycline-resistant isolates were Gram-negative bacteria. Six groups of oxytetracycline-resistant bacteria were classified using cluster analysis based on a comparison of levels of oxytetracycline resistance. Complex fingerprint patterns were obtained for 71 isolates studied. In general, the band patterns of isolates from different ponds were very similar, and the data indicated that the isolates were closely related. The exploration for cross-resistance found that most of the 71 oxytetracycline-resistant isolates were also resistant to tetracycline and chlortetracycline, but had a relatively low resistance to doxycycline. Many isolates showed higher chlortetracycline resistance than oxytetracycline resistance. Additionally, the oxytetracycline-resistant isolates were examined for the presence of tetracycline resistance (tet) genes. Fifty percent of the isolates carried one of the 14 known tet genes examined. The most common determinants were TetA and TetD. However, TetB, TetC, TetE, TetK, TetL, and TetM were also found with various frequencies.

• Plant Resources
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• v.5 no.3
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• pp.169-175
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• 2002

The soybean cyst nematode (Heterodera glycines Inchinoe; SCN) is a devastating pest of soybean and is responsible for significant losses in yield. The use of resistant cultivars is the effective method to reduce or eliminate SCN damage. The objective of this research is to identify AFLP markers linked to the SCN resistant genes. Bulked genomic DNA was made from resistant and susceptible genotypes to SCN and a total of 19 primer combinations were used. About 31 fragments were detected per primer combination. The banding patterns were readily distinguished in resistant and susceptible bulked genotypes. Polymorphic fragments were detected between resistant and susceptible bulked genotypes in the primer combination of CGT/GGC, CAG/GTG and CTC/GAG. In primer combinations of CGT/GGC and CAG/GTG, bulked resistant genotype produced a polymorphic bands. However, in primer of CTC/GAG, bulked susceptible genotype produced a polymorphic fragments. Three AFLP markers identified as a polymorphic fragments between bulked genomic DNA were mapped in 85 F2 population. Among them, only two markers, CGT/GGC and CTC/GAG, was linked and was mapped. Broad application of AFLP marker would be possible for improving resistant cultivars to SCN.

• Journal of Yeungnam Medical Science
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• v.28 no.1
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• pp.13-19
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• 2011

The emergence of antibiotic-resistant pathogens is a Serious clinical problem in the treatment of infectious diseases that increase mortality, morbidity, hospitalization length, and the cost of healthcare. In particular, $Streptococcus$ $pneumoniae$ is a major etiologic pathogen of pneumonia, sinusitis, otitis media, and meningitis. As the definition of penicillin resistance to $S.$ $pneumoniae$ was recently changed, macrolide-resistant $S.$ $pneumoniae$ is a major resistant pathogen in the community. Infections caused by antibiotic-resistant strains are associated with incorrect use of antibiotics and critical clinical outcomes. For the appropriate use of antibiotics to treat infections, physicians always should have up-to-date information on the current epidemiologic status of antibiotic resistance for common pathogens and their susceptibility to antimicrobials. Appropriate selection of antimicrobials, strict control of infection, vaccination, and development of a feasible national policy of infection control are important strategies for the control of antimicrobial resistance. This review article focuses on the current status of antibiotic-resistant $S.$ $pneumoniae$ in community-acquired pneumonia in Korea.

• Mycobiology
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• v.36 no.4
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• pp.270-273
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• 2008

Trichoderma spp. cause large crop losses of the cultivated shiitake mushroom, Lentinula edodes. We bred several shiitake strains that are resistant to Trichoderma spp. using di-mon mating to establish a useful method for controlling the greenmold disease. We examined the competitive ability of L. edodes against Trichoderma spp. using a dual culture system to select resistant strains. By screening Trichoderma-resistant strains, we found that among 11 parental strains, 4 strains, including KFRI 36, were confirmed resistant strains. They showed especially strong resistance to T. harzianum, which formed deadlock after mycelial contact and then invaded into the territory of T. harzianum. KFRI 171 also showed resistance to T. atroviride strains. Among 13 strains, which were made by hybridization of shiitake strains, 5 were confirmed to be resistant to Trichoderma, including KFRI 58-1. Their resistance was not correlated to the resistant activity of their parents’ strains. Two strains lose resistance and two strains acquire resistance compared to their parents’ strains. In SEM observation, the mycelium of L. edodes at the interaction zone of Lentinula-Trichoderma was rugged and swollen by T. harzianum.

• Toxicological Research
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• v.27 no.2
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• pp.85-93
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• 2011

Selective estrogen receptor modulators (SERMs) are synthetic molecules which bind to estrogen receptors (ER) and can modulate its transcriptional capabilities in different ways in diverse estrogen target tissues. Tamoxifen, the prototypical SERM, is extensively used for targeted therapy of ER positive breast cancers. Unfortunately, the use of tamoxifen is associated with acquired resistance and some undesirable side effects. This study investigated the availability of the conventional SERMs on the TAM-resistance breast cancer cells. SERMs showed more effectiveness in MCF-7 cells than tamoxifen resistant cells, except toremifene and ospemifene. Especially, toremifene was more efficacious in tamoxifen resistant cells than MCF-7. Ospemifene had similar cytotoxic activity on the two types of breast cancers. The other SERMs used in this experiment didn't inhibit efficiently the proliferation of tamoxifen resistant cells. These results support the possibility to usage of toremifene on tamoxifen resistant cancer. The effectiveness by toremifene on tamoxifen resistant cells might be different pathways from the apoptosis and the autophagy. Further study should be needed to elucidate the underlying mechanism of effect of toremifene on tamoxifen resistant cancer.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.193-197
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• 2010

Stretch wrapping processes that are used to the packaging process had a serious problem of high price and treatment of used wraps. On the other hand, slip-resistant adhesive provides the advantage of simple process, low cost, and free from after-use treatment. In this research, adhesion deterioration of aqueous slip-resistant adhesive adhered to polyethylene film under the moisture condition using aqueous slip-resistant adhesive was observed by the Peel Test. Improvement of adhesive property under the moisturizing condition could be obtained by the selection of appropriate additives. As a result, introduction of maltodextrin reduced the deterioration of slip-resistant adhesion owing to the improved moisture resistance and introduction amount of 10 wt% of maltodextrin showed optimal performance.

• Journal of Microbiology and Biotechnology
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• v.29 no.3
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• pp.465-472
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• 2019

Several reports describe antimicrobial-resistance transfer among children and the community in outbreak situations, but transfer between a child and a caregiver has not been examined in child care facilities under normal circumstances. We investigated the transfer of antimicrobial-resistance genes, resistant bacteria, or both among healthy children and teachers. From 2007 to 2009, 104 Escherichia coli isolates were obtained from four teachers and 38 children in a child care center. Twenty-six cephem-resistant isolates were obtained from children in 2007 and 2008. In 2009, cephem-resistant isolates were detected in children as well as a teacher. Nalidixic acid-resistant isolates from the same teacher for 3 years showed low similarity (<50%) to each other. However, an isolate from a teacher in 2007 and another from a child in 2008 showed high similarity (87%). Pulsed-field gel electrophoresis revealed 100% similarity for four isolates in 2007 and one isolate in 2008, and also similarity among seven isolates carrying the virulence gene (CNF1). This study yielded the following findings: (1) a gene for extended-spectrum ${\beta}$-lactamase was transferred from a child to other children and a teacher; (2) a nalidixic acid-resistant isolate was transferred from a teacher to a child; and (3) a virulent bacterium was transferred between children.