• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.151-159
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• 2002

Genetic map and molecular marker have a great importance in improving and facilitating crop breeding program as well as in genome analysis and map-based cloning of genes representing desirable characters. This study aimed at developing RAPD markers and constructing a genetic linkage map using 82 BC$_1$F$_1$individuals originated from the cross between '835' and B$_2$in radish (Raphanus sativus L.). One of the parents for genetic linkage map construction, '835'(P$_1$) of egg type is susceptible to Fusarium wilt and have medium resistance to virus infection and the other parent, B$_2$(P$_2$) of round type, is susceptible to Fusarium wilt and virus, Screening of 394 RAPD primers in BC$_1$F$_1$) population resulted in selecting 128 polymorphic markers which displayed 1:1 segregation pattern. Two markers failed to display 1:1 segregation and showed the segregation ratio skewed to maternal genotype. Selected markers were categorized into 14 linkage group based on LOD score represented by MAPMAKER/EXP program. Five groups composed of single marker among them were excluded from the linkage map, and consequently, the remaining groups are well matched with the number of radish chromosome (n＝9). The linkage map constructed with 128 markers covers 1,688.3 cM and the average distance between markers was 13.8 cM. For developing STS marker, we determined the partial nucleotide sequence of OPE10 marker at both ends and designed a oligonucleotide primer pair based on this sequence. STS PCR using the primer pair displayed a single, clear band of which segregation is perfectly matched with that of OPE10 marker. This implies that RAPD markers could readily convert into clear and reliable STS markers.

• Journal of Life Science
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• v.7 no.4
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• pp.392-401
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• 1997

The poliovirus is a small, and non-enveloped virus. The RNA genome of poliovirus is continuous, linear, and has a single open reading frame. This polyprotein precursor is cleaved proteolytically to yield mature products. Most of the cleavages occur by viral protease. The mature proteins derived from the P1 polyprotein precursor are the structural components of the viral capsid. The initial cleavage by 2A protease is indirectly involved in the cleavage of a cellular protein p220, a subunit of the eukaryotic translation initiation factor 4F. This cleavage leads to the shut-off of cap-dependent host cell translation, and allows poliovirus to utilize the host cell machinery exclusively for translation its own RNA, which is initiated by internal ribosome entry via a cap-independent mechanism. The functional role of the 2B, 2C and 2BC proteins are not much known. 2B, 2C, 2BC and 3CD proteins are involved in the replication complex of virus induced vesicles. All newly synthesized viral RNAs are linked with VPg. VPg is a 22 amino acid polypeptide which is derived from 3AB. The 3C and 3CD are protease and process most of the cleavage sites of the polyprotein precursor. The 3C protein is also involved in inhibition of RNA polymerase II and III mediated transcription by converting host transcription factor to an inactive form. The 3D is the RNA dependent RNA polymerase. It is known that poliovirus replication follows the general pattern of positive strand RNA virus. Plus strand RNA is transcribed into complementary minus strand RNA that, in turn, is transcribed for the synthesis of plus strand RNA is transcribed into complementary minus strand RNA that, in turn, is transcribed for the synthesis of plus strand RNA strands. Poliovirus RNA synthesis occurs in a membranous environment but how the template RNA and proteins required for RNA replication assemble in the membrane is not much known. The RNA requirements for the encapsidation of the poliovirus genome (packaging signal) are totally unknown. The poliovirus infection cycle lasts approximately 6 hours.

• Pediatric Infection and Vaccine
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• v.28 no.2
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• pp.82-91
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• 2021

Background: The purpose of this study was to investigate the association between antibiotic use and the antimicrobial resistance of gram-negative bacteria isolated from blood cultures in a pediatric population. Methods: From January 2014 to June 2018, the antibiotic resistance pattern of Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa obtained from bacteremic patients aged ≤18 years hospitalized at Asan Medical Center Children's Hospital was analyzed and the parenteral antibiotic consumption data were retrieved. Results: During the study period, the blood culture was positive for K. pneumoniae (6.4%; 105/1,628), E. coli (5.6%; 91/1,628), P. aeruginosa (3.3%; 54/1,628), and A. baumannii (2.5%; 41/1,628), and the extended-spectrum antibiotic resistance rate of gram-negative bacteria was consistently high. The overall resistance rate of E. coli and K. pneumoniae to extendedspectrum cephalosporin was 49.3% and 54.4%, respectively. Carbapenem-resistant E. coli was first detected in 2014; its overall resistance rate to carbapenem was 5.3%. There was a linear correlation between the usage of 3rd generation cephalosporin and the resistance of A. baumannii (r²=0.96, P=0.004) and carbapenem usage and the resistance of K. pneumoniae (r²=0.79, P=0.045). Conclusions: A positive linear correlation was observed between antibiotic resistance and the corresponding antibiotic usage in 3rd generation cephalosporin resistant A. baumannii and carbapenem resistant K. pneumoniae. The judicious use of antibiotics in healthcare settings is important to minimize selection for extended-spectrum β-lactamase (ESBL) and carbapenem resistance in gram-negative bacteria.

• Tuberculosis and Respiratory Diseases
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• v.85 no.1
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• pp.37-46
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• 2022

Background: Although respiratory tract infection is one of the most important factors triggering acute exacerbation of chronic obstructive pulmonary disease (AE-COPD), limited data are available to suggest an epidemiologic pattern of microbiology in South Korea. Methods: A multicenter observational study was conducted between January 2015 and December 2018 across 28 hospitals in South Korea. Adult patients with moderate-to-severe acute exacerbations of COPD were eligible to participate in the present study. The participants underwent all conventional tests to identify etiology of microbial pathogenesis. The primary outcome was the percentage of different microbiological pathogens causing AE-COPD. A comparative microbiological analysis of the patients with overlapping asthma-COPD (ACO) and pure COPD was performed. Results: We included 1,186 patients with AE-COPD. Patients with pure COPD constituted 87.9% and those with ACO accounted for 12.1%. Nearly half of the patients used an inhaled corticosteroid-containing regimen and one-fifth used systemic corticosteroids. Respiratory pathogens were found in 55.3% of all such patients. Bacteria and viruses were detected in 33% and 33.2%, respectively. Bacterial and viral coinfections were found in 10.9%. The most frequently detected bacteria were Pseudomonas aeruginosa (9.8%), and the most frequently detected virus was influenza A (10.4%). Multiple bacterial infections were more likely to appear in ACO than in pure COPD (8.3% vs. 3.6%, p=0.016). Conclusion: Distinct microbiological patterns were identified in patients with moderate-to-severe AE-COPD in South Korea. These findings may improve evidence-based management of patients with AE-COPD and represent the basis for further studies investigating infectious pathogens in patients with COPD.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.476-484
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• 2022

This study was conducted to investigate the effect of closed cultivation and open cultivation method and substrate type on the nutrient ion change pattern and growth of sweet pepper (Capsicum annuum L.) 'Scirocco' according to the reuse of drainage in hydroponics. The sowing, transplanting, and application of the closed and open cultivation method were carried out on August 19 and September 16, and October 21, 2021, respectively. As a result of the analysis of nutrients in the drainage, Na⁺ and Cl^- are representative ions that crops do not absorb properly, and as the growth progresses, they are accumulated in the closed method. In addition, since the content of NH₄-N in the drainage is significantly lower than that of NO₃-N, it is thought that NH₄-N is preferentially absorbed rather than NO₃-N due to the ion selectivity of sweet pepper. The growth and fruit characteristics of sweet pepper did not differ significantly between treatments according to the drainage reuse and the type of substrate. In conclusion, if you take care of poor fruiting due to the weakening of power after the middle period in hydroponic cultivation of sweet pepper according to the cultivation method of closed and open, and the substrate type of coir and rock wool, the difference between treatments is not large, so the sweet pepper can be produced by selecting the cultivation methods and substrate types suitable for the conditions of grower. However, as interest in environmental pollution has recently increased, it is judged that there is no need to worry about a decrease in quantity or quality, even if a closed cultivation method is adopted under the assumption that pathogen infection due to drainage reuse is well managed. It is expected that if coir is applied instead of rock wool, which causes a problem of disposal, it will further contribute to the reduction of environmental pollution.

• Childhood Kidney Diseases
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• v.4 no.1
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• pp.25-32
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• 2000

Purpose: This retrospective study of 126 children with symptomless primary hematuria was undertaken to determine the distribution of various histologic types by renal biopsy, clinical outcome according to the biopsy findings and also to find out feasibility of performing renal biopsy in these children. Patients and Methods : Study population consisted of 126 children with symptom-less primary hematuria who have been admitted to the pediatric department of Kyung-poot National University Hospital for the past 11 years from 1987 to 1998 and renal biopsy was performed percutaneously. Hematuric children with duration of less than 6 months, evidences of systemic illness such as SLE or Henoch-Schonlein purpura, urinary tract infection, and idiopathic hypercalciuria were excluded from the study. Results : Mean age of presentation was 9.2${\pm}$3.3 years (range ; 1.5-15.3 years) and male preponderance was noted with male to female ratio of 2:1. IgA nephropathy was the most common biopsy finding occuring in 60 children ($47.6\%$), followed by MsPGN in 13 ($10.3\%$), MPGN in 5 ($3.9\%$), TGBM in 6 ($4.7\%$), Alport syndrome in 2 ($1.6\%$), FSGS in 1 ($0.8\%$), and in 39 children ($30.9\%$), 'normal' glomeruli were noted. Recurrent gross hematuria was more common than persistent microscopic hematuria (84 versus 42), and especially in IgA nephropathy, recurrent gross hematuria was the most prevalent pattern of hematuria. In 58 out of 126 cases ($46.0\%$), hematuria was isolated without accompa-nying proteinuria and this was especially true In cases of MsPGN and 'normal' glomer-uli by biopsy finding. Normalization of urinalysis (disappearance of hematuria) in IgA nephropathy, MsPGN and 'normal' glomuli group were similar and it was $14\%,\;27\%\;and\;21\%$ respectively during 1-2 years of follow-up period, and $37.1\%,\;40\%\;and\;35\%$ respectively during 3-4 years of follow-up periods. However, abnormal urinalysis persi-sted in the majority of children with MPGN, TGBM. Alport syndrome and FSGS. Renal function deteriorated progressively in 6 cases (3 with IgA nephropathy, 2 with Alport syndrome and 1 with TGBM). Conclusion : In summary, present study demonstrates that in 126 children with symptomless primary hematuria, IgA nephropathy was the most common biopsy findings followed by MsPGN, MPGN, TGBM, Alport syndrome and FSGS, and 'normal glomeruli' was also seen in 39 cases ($30.9\%$). Renal histology could not be predictable on the clinical findings, so that to establish appropriate long-term planning for these children, we would recommend to obtain precise histologic diagnosis by renal biopsy.

• Pediatric Infection and Vaccine
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• v.5 no.2
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• pp.230-238
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• 1998

Purpose : Worldwidely, the incidence of the hepatitis A has been markedly decreased in the past years. Also in Korea, there has been only a few sporadic cases without evidence of epidemics since the mid 1980s. However, the incidence of the hepatitis A in young adults and childen has been in trends of increasing since 1996. So, we retrospectively performed the study on the epidemiolgical changes and the clinical feature of hepatitis A in childen, living in Kyung-gi province, since 1988 to 1998. Methods : The four affiliated hospitals of the Catholic University of Korea, Our lady of Mercy's hospital, Holy family hospital, Eui-Jung-bu St. Mary's hospital, and St. Vincent hospital, were enrolled in this study. We conducted statistical analysis on the incidence of hepatitis A since 1988 to 1998, concerning with the period (monthly, annually), age, sex and related epidemiological property, by reviewing the hospital records of the patients with hepatitis A. We simultaneously performed the study concerning with the clinical characteristics of hepatitis A. Results : 1) During the study period, 46 children was diagnosed as hepatitis A, and among them 28 children (60.1%) developed sporadically in the 1998. And sex ratio was 1.2(male):1(female). 2) Most of the patients developed between March and July, and hepatitits A were mainly developed in the patients above the 10 year old ages(37 patients; 80.4%). 3) The socioeconomic and educational status of the patient's parents was almostly below the middle and low class. Although, we could not find the etiological factors in most cases, but we found the evidence of interfamilial transmission in one family. 4) The patients complained the symptoms of nausea and vomiting, jaundice, poor appetite, mild fever, fatigueness, abdominal pain, URI symptom, dyspepsia, dark urine, headache and diarrhea in order, and findings of jaundice, hepatomegaly, RUQ tenderness, splenomegaly and LLQ tenderness in order were seen. 5) All patients showed abnormal findings of the liver function tests, and the pattern of cholestatic hepatitis were seen in most cases, but these findings were normalized within the 2~4 weeks. The findings of the gall bladder wall thickening, hepatomegaly, splenomegaly and ascites were seen on abodominal sonogram. 6) The prognosis of all patients were good without complications, except in one case who had the episode of transient recuurence. And the mean hospitalization dates were 11.1 days. Conclusion : We found that the incidence of hepatitis A showed the increasing trend, and peaked in the 1998 in Kyung-gi province children. And hepatitis A mainly developed in children above the 10 year old ages. The scioeconomic and educational status of patient's family was almostly below the middle class. All of them showed abnormal liver function, and clinically cholestatic hepatitis features were seen in most cases. But, the prognosis was excellent without complication in all cases.