• Journal of Life Science
• /
• v.22 no.5
• /
• pp.600-604
• /
• 2012

Rotavirus is the main cause of severe diarrhea in infants and young children of the world. However, the frequency of genetic alterations makes it hard to control the prophylaxis. Therefore, continuous monitoring of the rotavirus's genetic change is inevitable to prevent disease prevalence and is useful in inventing an efficient vaccine. From January 2005 to December 2010, we investigated 11,607 stool samples of acute gastroenteritis patients in the Incheon metropolitan area. About 13.18% (1,530 stool samples) of all samples had a positive reaction against rotavirus using an antigen capture enzyme-linked immunosorbent assay (ELISA). Then, the 160 stool samples were searched for subtypes of group A rotavirus by using a reverse transcription polymerase chain reaction (RT-PCR) and a nested multiplex RCR. In P sub-typing, P8 (56.3%) was an extremely prevalent genotype, followed by P6 (21.3%), and P1A (10.0%). G1 (39.4%) was most widespread in the G subtype, followed by G4 (25.0%) and G3 (18.8%). G1P8 (35.5%) was the most common G and P subtype combination, followed by G4P6 (19.3%) and G3P8 (13.1%). These results might be useful data for understanding the epidemiological status of group A-rotavirus dispersion in the Incheon metropolitan area.

• Pediatric Infection and Vaccine
• /
• v.16 no.2
• /
• pp.175-182
• /
• 2009

Purpose : A number of countries have experienced an increase in pertussis during the past decade. In particular, there has been an increase in the incidence rate among adolescents and adults. To learn more about the current epidemiology of pertussis, we studied the prevalence and clinical characteristics of pertussis in children in Cheonan, South Korea. Methods : We collected nasopharyngeal aspirates of 118 patients who were treated for respiratory symptoms at Dankook Univeristy Hospital between March 2008 and September 2009. We performed multiplex PCR for detection of Bordetella pertussis in those aspirates. Results : Of the 118 patients, 10 (8%) were positive by PCR for B. pertussis. Six episodes occurred during the period July to September 2009. Nine of the 10 patients were less than 3 months old. Seven of them had not received DTaP vaccine. The mean duration of coughing before diagnosis was 10.9${\pm}$5.2 days. Ten patients (100%) had paroxysmal cough and 8 (80%) had post-tussive vomiting. Only one patient had fever. One who had complications that include pneumonia, atelectasis and pneumomediastinum developed an absolute increase in leukocyte count (84,400/$mm^3$). There was a statistically significant relation between vaccine being received and development of complications (P =0.033). Conclusion : We suspect that there was an epidemic of pertussis between July and September 2009. Further investigation by a pediatric or nationwide surveillance system is needed to monitor the changing epidemiology for pertussis.

• Annals of Clinical Microbiology
• /
• v.21 no.4
• /
• pp.86-91
• /
• 2018

Background: The PANA RealTyper HPV kit (PANAGENE, Korea; PANA RealTyper) was developed to genotype human papillomavirus (HPV) and was based on multiplex real-time PCR amplification and melting curve analysis. In this study, we compared PANA RealTyper to the AdvanSure HPV GenoBlot assay (LG Life Sciences, Korea; AdvanSure assay) and attempted to evaluate the performance of PANA RealTyper. Methods: A total of 60 cervical specimens were collected from women undergoing routine cervical cancer screening. The AdvanSure assay and PANA RealTyper kit identified the same 20 high-risk genotypes. However, the AdvanSure assay identified 15 low-risk genotypes, while the PANA RealTyper kit identified only 2 but detected 18 low-risk genotypes. Results: Among the total 60 specimens, 54 high-risk genotypes (40 specimens) and 20 low-risk genotypes (18 specimens) were detected. The agreement rates of the assays ranged from 94.4 to 100% for high-risk genotypes. Among 9 genotypes that were positive in the PANA RealTyper kit but negative in the AdvanSure assay, 7 were confirmed as true positive (HPV genotypes 16 (n=1), 39 (n=1), 52 (n=1), 58 (n=2), 68 (n=2)). Among 4 genotypes that were negative in the PANA RealTyper kit but positive in the AdvanSure assay, 3 were confirmed as HPV genotype 59. Among the 19 low-risk genotypes positive in the AdvanSure assay, there were 2 cases of HPV 6 and 1 case of HPV 11. In comparison, only 1 positive case of HPV 6 was determined by the PANA RealTyper kit. Conclusion: The PANA RealTyper kit was comparable with the AdvanSure assay. The PANA RealTyper kit would be useful and suitable for HPV genotyping in the clinical laboratory.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.12
• /
• pp.4915-4920
• /
• 2015

Background: : Familial adenomatous polyposis (FAP) is an autosomal dominant inherited disease mainly caused by mutations of the adenomatous polyposis coli (APC) gene with almost complete penetrance. These colorectal polyps are precancerous lesions that will inevitable develop into colorectal cancer at the median age of 40-year old if total proctocolectomy is not performed. So identification of APC germline mutations has great implications for genetic counseling and management of FAP patients. In this study, we screened APC germline mutations in Chinese FAP patients, in order to find novel mutations and the APC gene germline mutation characteristics of Chinese FAP patients. Materials and Methods: The FAP patients were diagnosed by clinical manifestations, family histories, endoscope and biopsy. Then patients peripheral blood samples were collected, afterwards, genomic DNA was extracted. The mutation analysis of the APC gene was conducted by direct polymerase chain reaction (PCR) sequencing for micromutations and multiplex ligation-dependent probe amplification (MLPA) for large duplications and/or deletions. Results: We found 6 micromutations out of 14 FAP pedigrees, while there were no large duplications and/or deletions found. These germline mutations are c.5432C>T(p. Ser1811Leu), two c.3926_3930delAAAAG (p.Glu1309AspfsX4), c.3921_3924delAAAA (p.Ile1307MetfsX13), c3184_3187delCAAA(p.Gln1061AspfsX59) and c4127_4126delAT (p.Tyr1376LysfsX9), respectively, and all deletion mutations resulted in a premature stop codon. At the same time, we found c.3921_3924delAAAA and two c.3926_3930delAAAAG are located in AAAAG short tandem repeats, c3184_3187delCAAA is located in the CAAA interrupted direct repeats, and c4127_4128 del AT is located in the 5'-CCTGAACA-3', 3'-ACAAGTCC-5 palindromes (inverted repeats) of the APC gene. Furthermore, deletion mutations are mostly located at condon 1309. Conclusions: Though there were no novel mutations found as the pathogenic gene of FAP in this study, we found nucleotide sequence containing short tandem repeats and palindromes (inverted repeats), especially the 5 bp base deletion at codon 1309, are mutations in high incidence area in APC gene,.

• Clinical and Experimental Pediatrics
• /
• v.52 no.11
• /
• pp.1241-1248
• /
• 2009

Purpose:The etiology of Kawasaki disease (KD) is still unknown. Recently, an association between human coronavirus NL63 (HCoV-NL63) and KD was implicated. Hence, we attempted to determine the association between KD and acute respiratory viral infections. Methods:Nasopharyngeal aspirate samples were obtained from 54 patients diagnosed with KD at the Seoul National University (SNU) Children's Hospital and SNU-Bundang Hospital between October 2003 and September 2006. Viral diagnoses of 11 respiratory viruses were made using multiplex reverse transcriptase-polymerase chain reaction (RT-PCR): respiratory syncytial virus (RSV), adenovirus, rhinovirus (RV), parainfluenza viruses (PIVs) 1 and 3, influenza viruses (IFVs) A and B, human metapneumovirus (HMPV), human bocavirus (HBoV), HCoV OC43/229E, and HCoV-NL63. Clinical data were reviewed retrospectively. Results:The median age was 32 months (6 months-10.4 years). Respiratory symptoms were observed in 37 patients (69%). The following respiratory viruses were identified in 12 patients (22%): RV (n=4), PIV-3 (n=2), HBoV (n=2), and adenovirus, RSV, PIV-1, IFV-A, and HCoV-NL63 (n=1). Co-infection with PIV-3 and RV was observed in one patient. Respiratory symptoms were observed in 7 (58.3%) and 30 (71.4%) patients of the virus-positive and virus-negative groups (P>0.05). Response rate to intravenous immunoglobulin administration was 67% (n=8) and 86% (n=36) in the virus- positive and virus-negative groups (P>0.05). Conclusion:Respiratory symptoms were commonly observed in KD patients but the association between respiratory viruses and KD were not found. Large multicenter-based investigations are required to confirm the association between acute respiratory viral infections and KD.

• Journal of Food Hygiene and Safety
• /
• v.35 no.5
• /
• pp.438-446
• /
• 2020

Meju and nuruk (respectively soybean and malt) are traditional Korean fermentation starters that are vulnerable to contamination by harmful microorganisms such as aflatoxigenic fungi and their associated aflatoxins (AFs). In this study, Aspergillus spp. were isolated and identified from a total of 57 meju and 18 nuruk samples collected from Korean markets. Their potential aflatoxigenicity was investigated by examining the presence of three aflatoxin biosynthetic genes (aflO, aflP, and aflR) using multiplex polymerase chain reaction (mPCR) assays. Thereafter, aflatoxin production of isolates and the natural occurrence of AFs in meju and nuruk samples were analyzed by high-performance liquid chromatography (HPLC). A total of 177 Aspergillus isolates were identified and 130 isolates were obtained from meju samples. Of these, 25 isolates (19.2%) contained all three aflatoxin biosynthetic genes, and five (20%) of these isolates produced aflatoxins. Forty-seven of the Aspergillus isolates were obtained from nuruk samples, five of which (10.6%) expressed all three AF biosynthetic genes; however, none of these strains produced AFs. HPLC analysis showed that 88% (51/58) of the meju samples and 39% (7/18) of nuruk samples were not contaminated with AFs (below limit of detection). Among the isolates isolated from meju and nuruk, there were aflatoxigenic strains containing all three aflatoxin biosynthetic genes or producing aflatoxin in medium, but the frequency of aflatoxin contamination was low in the meju and nuruk samples.

• Tuberculosis and Respiratory Diseases
• /
• v.55 no.1
• /
• pp.88-97
• /
• 2003

Background : Although smoking is a major cause of chronic obstructive pulmonary disease (COPD), only 10-20% of cigarette smokers develop symptomatic COPD, which suggests the presence of genetic susceptibility. This genetic susceptibility to COPD might depend on variations in the activities of the enzyme that detoxify hazardous chemical products, such as microsomal epoxide hydrolase (mEPHX) and glutathione-S transferase M1 subunit (GSTM1) genes. Methods : The genotypes of 58 patients with COPD, and 79 age matched control subjects, were determined by a polymerase chain reaction, followed by restriction fragment length polymorphism (PCR-RFLP) for the mEPHX, and multiplex PCR for the GSTM1. Results : GSTM1 was deleted in 53.3% of the subjects. There was no difference in GSTM1 deletion rates between the COPD patients (32/58, 55.2%) and the control subjects (41/79, 51.9%). The combination patterns of two polymorphisms of mEPHX showed slow enzyme activity in 29(21.2%), normal in 73(53.3%) and fast in 32(23.4%). The COPD group (7/57, 12.3%) showed a significantly lower incidence of slow enzyme activity compared to the control subjects (22/77, 28.6%, p<0.05). However, when the COPD and control groups were compared with smokers only, there were no significant differences in the genotypes of GSTM1 and mEPHX. Conclusion : The genotypes of GSTM1 and mEPHX were not significant risk factors of COPD in this cohort of study.

• Pediatric Infection and Vaccine
• /
• v.18 no.2
• /
• pp.154-162
• /
• 2011

Purpose : The aim of this study was to identify the clinical characteristics of lower respiratory tract infection due to respiratory syncytial virus (RSV) in young children and to provide information for an effective guideline for palivizumab administration in Korea. Methods : We reviewed medical charts of 167 patients under 3 years of age who were hospitalized in Dongguk University Ilsan Hospital for lower respiratory tract infection between January 2007 and February 2011. Diagnosis of the virus was made based on the multiplex real time polymerase chain reaction. Results : There were 113 patients who were infected by respiratory syncytial virus. 90 patients were term infants and 23 patients were preterm infants. No difference was shown between term and preterm infants except the days of admission which was 9.0${\pm}$6.0 days and 12.6${\pm}$21.0 days respectively. In the preterm group their mean age at the time of admission was 5.21${\pm}$4.9 months and the mean gestational age was 33.1${\pm}$4.3 weeks, and the mean birth weight was 2,152${\pm}$950 g. Only 4 patients were born under 28 weeks gestational age and were candidates for palivizumab administration. Conclusion : Most of the patients with severe RSV lower respiratory tract infection were term or near term infants who were not candidates for palivizumab prophylaxis. A nationwide study is needed to make a new risk stratified guideline for RSV prophylaxis for our country.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.14 no.2
• /
• pp.148-154
• /
• 2011

Purpose: We aimed to study the distribution of rotavirus genotypes (VP7 and VP4) and disease severity of rotavirus gastroenteritis prevalent in our community. Methods: Stool samples were collected from 156 children who were hospitalized with rotavirus gastroenteritis from December 2007 to June 2008. The disease severity of all patients was scored using the Vesikari scale. After extraction of ds-RNA of the rotavirus, cDNA synthesis using reverse transcription and polymerase chain reaction (RT-PCR) and multiplex PCR was performed. Following this, the final identification of genotypes was performed. Results: Of the 156 samples, VP7(G) and VP4(P) genotypes were identified in 147 (94.2%) and 140 (89.7%) samples, respectively. G1 (116 of 147 samples; 78.9%) and P[8] (137 of 140 samples; 97.9%) were the most prevalent, respectively. Of the 138 samples identified of combination types of VP7 and VP4, G1P[8] (111 samples; 80.4%) was the most prevalent. Other combination types varied with very low distribution rates. 9.4% of genotypes were not included in the new vaccines. The disease severity score was $11.8{\pm}3.3$ ($mean{\pm}2SD$). The distribution of disease severity was mild or moderate in 37.8% and severe in 62.2% of patients. Conclusion: The most prevalent genotype combination of rotavirus was G1P[8] and genotypes not included in the vaccines represented 9.4% in our community. Disease severity distribution of hospitalized children with rotavirus gastroenteritis was higher in the severe than in the mild and moderate categories.

• Journal of Genetic Medicine
• /
• v.5 no.1
• /
• pp.26-33
• /
• 2008

Purpose : Phenylketonuria(PKU) is an inborn error of metabolism and a genetic disorder resulting from a deficiency of phenylalanine hydroxylase(PAH) and decreased activity of tetrahydrobiopterin(BH4).In this study the correlation between the DNA mutation and clinical manifestations was investigated and PAH DNA mutations were compared bewteen Asian and Caucasian populations. Methods : DNA was isolated from peripheral leukocytes. The PAH gene was amplified by Polymerase Chain Reaction(PCR) and the sequence was analyzed with Multiplex Ligation-dependent Probe Amplification(MLPA). Results : We characterized the PAH gene of 102 independent Korean patients with PKU. PAH nucleotide sequence analysis revealed 44 different mutations, including 10 novel mutations comprising 9 missense mutations(N207D, K95del, A447P, G344D, P69S, S391I, A202T, G103S, and I306L) and 1 novel splice-site variant mutation(IVS10-3C>G). R243Q was the most prevalent mutation in this study. A259T has not previously been reported in Asian populations, but we found that this mutation had a frequency of 10.1% in our study. Furthermore, the genotypes of $BH_4$ responsive patients were analyzed and were divided into two groups: $BH_4$ medication-only group and $BH_4$ medication with diet therapy group. In the $BH_4$ medication-only group and $BH_4$ medication with diet therapy group, R241C was the most common mutation. Conclusion : Novel mutations in the PAH gene of PKU patients are still being discovered. Additional information as to the frequency of mutations in the tetrahydrobiopterine responsive gene is also accumulating. We anticipate that knowledge of these PKU gene mutations will assist the diagnosis, genetic counseling, and therapeutic treatment of PKU patients in future.