• Korean Journal of Microbiology
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• v.47 no.2
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• pp.117-123
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• 2011

The purpose of this study was to evaluate and compare different elution and concentration methods for optimization of human rotavirus (HRV) detection method using real-time RT-PCR and cell culture techniques. The leafy vegetable samples (lettuce, Chinese cabbage) were artificially inoculated with HRV. Viruses were extracted from the vegetables by two different elution buffers, buffer A (100 mM Tris-HCl, 50 mM glycine, 3% beef extract, pH 9.5) and buffer B (250 mM Threonine, 300 mM NaCl, pH 9.5), and the extracted viruses were concentrated by filtration and PEG precipitation sequentially. To determine infectivity of the viruses, the viruses recovered from the samples were infected to the MA-104 cells, and integrated cell culture real-time RT-PCR was performed at 1, 48, 72, 96, 120, 144, 168 h post-infection (p.i.). The elution buffer A was more efficient in extracting the virus from the produce samples tested than the buffer B, 29.54% and 18.32% of recoveries, respectively. The sensitivity of real-time RT-PCR method was markedly improved when the virus was concentrated by the filtration method. When the viruses were eluted and concentrated by buffer A and filtration, respectively, the average recovery rate was approximately 51.89%. When the viruses recovered from samples were infected to MA-104 cell, infectious HRV was detected within 48 h p.i. by ICC/real-time RT-PCR, whereas cytopathic effects were not observed until 72 h p.i. The optimized detection method evaluated in this study could be useful for rapid and reliable detection of HRV in fresh produce products and applied for detection of other food-borne viruses.

• Korean journal of applied entomology
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• v.7
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• pp.5-13
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• 1969

Present system of seed potato production in Korea has several weak points and consequently has difficulties in covering annual shortage of 60,000 tons of seed potatoes. The author has an opinion that this so called 'High land system' of seed potato production adopted by the Government should be replaced by the 'Coastal area system' which is proposed by the author and has many advantages over present 'High land system'(2). In coastal areas where enormous acreage of rice paddies are spread, mostly around the villages. the primary host plants of the vectors are found. Therefore, the only source of aphid vectors are limited to the villages. The farmer's houses scattered more sparsely also have minor importance. In the previous paper(2), the author reported that the aphid vector populations were lower in the coastalareas than at Taegwanryong where the Alpine Experiment Station for the production. of seed potatoes is located. However, the number to vectors at Okku showed rather high density, where the trap was placed at the distance of 200 m from a village where peach and Hibiscus trees, the primary hosts of Myzus pesrsicae and Aphis gossypii were grown. To clarify the flight distance from the source of the aphid vectors, a trial was carried out in the Kwanghwal area, Kimje-gun, Cholla-pukto. on the western coast. 13 traps were placed at four directions and the distances between the traps were 250 m. (Fig. I) The traps 'Were operated from June 21 to October 31. The results are shown in Table 1. A total of some 70 species of aphids were found, including 5 speceis of potato virus vectors. The vectors are as follows: I. Myzus persicae (Sulzer) 2. Aphis gossypii Glover 3. Aulacorthum solani (Kaltenbach) 4. Lipaphis erysimi (Kaltenbach) 5. Macrosiphoniella sanborni (Gillette) Out of a total of 12,797 aphids, 5,187$(48\%)$ vectors were found. The trap catches at the 13 locations are shown in Fig. 2 and the numbers of the vectors at each location for each vector, except Macro-siphoniella sanborni. of which only a single individual was caught, are shown in Fig. 3-6. Number of vectors at C (3,279) (Centre of the village) is considerably higher than that at Suwon (763); however, EI. SI. WI and NI. where the distanecs from Care 250 m, showed lower numbers of vectors than that at Taegwanryong (347). The number of vectors at NI was rather than at the other 3 locations at the distance of 250m from the village. This was because C was in the southern part of the village. Consequently NI was much closer to the village than the other 3 locations of the same distance from C. Numbers of catches of the most important vector. Myzus persicae, are shown in Fig.3. The distribution pattern is typical except $S-2\;and\;W_3$, where several farmer's houses were found. If only the rice paddies were found in these locations. the numbers of the vectors would be small as the distances increase. Numbers of catches of the other 3 vectors are shown in Fig. 4-6. From these results. the author has drawn the following conclusions: 1. The aphid vector sources at the rice paddy belt in the western coast are the villages. 2. The vector densities at the locations where the distances are 250 m from the centre of the village are lower than that at Taegwanryong. 3. The vector densities become gradually lower as the distances from the centre of village increase. However. depending on the host plant situation at each location, the vector densities are variable. These minor sources of aphid vectors may be eliminated so that seed potatoes can be grown. 4. Thus. under the direction of specialists, fields suitable for seed potato production can be found in the coastal areas.

• Pediatric Infection and Vaccine
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• v.30 no.3
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• pp.129-138
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• 2023

Purpose: Cancer incidence is known to be higher in patients with inborn errors of immunity (IEI) compared to the general population in addition to traditionally well-known infection susceptibility. We aimed to investigate cancer occurrence in patients with IEI in a single center. Methods: Medical records of IEI patients treated at Samsung Medical Center, Seoul, Korea were retrospectively reviewed from November 1994 to September 2023. Patients with IEI and cancer were identified. Results: Among 194 patients with IEI, seven patients (3.6%) were diagnosed with cancer. Five cases were lymphomas, 4 of which were Epstein-Barr virus (EBV)-associated lymphomas. The remaining cases included gastric cancer and multiple myeloma. The median age at cancer diagnosis was 18 years (range, 1-75 years). Among patients with cancer, underlying IEIs included X-linked lymphoproliferative disease-1 (XLP-1, n=3), activated phosphoinositide 3-kinase delta syndrome (APDS, n=2), and cytotoxic T-lymphocyte antigen 4 (CTLA-4) haploinsufficiency (n=2). Seventy-five percent (3/4) of XLP-1 patients, 40.0% (2/5) of APDS patients, and 50.0% (2/4) of CTLA-4 haplo-insufficiency patients developed cancer. Patients with XLP-1 developed cancer at earlier age (median age 5 years) compared to those with APDS and CTLA-4 (P<0.001). One patient with APDS died during hematopoietic cell transplantation. Conclusions: Cancer occurred in 3.6% of IEI patients at a single center in Korea. In addition to infectious complications and inflammation, physicians caring for IEI patients should be aware of the potential risk of cancer, especially in association with EBV infection.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.337-345
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• 1995

To evaluate the pathogenicity and immunogenicity of Eimeria tenella to the chicken treated with dexamethasone(DEX) and testosterone propionate (TES), we administered 0.1ml/chicken of dexamethasone and 40mg/chicken of testosterone propionate at 1-, 2-, and 7-days old, respectively. We also immunized with ND oil-emulsion vaccine at 2 weeks old. After that, we immunized and challenged with 100 and $1{\times}10^5$ oocysts/chicken of E tenella at 2 and 4 weeks old, respectively. And then we investigated the HI titers for ND virus, survival rate, body weight gain, lesion score and the weight of the bursa of Fabricius and thymus. The titers for ND virus in the groups treated with TES were higher than those in the groups treated with DEX and CON during 3 to 6 weeks. After challenge, the survival rate of testosterone propionate treated-challenged(TES-CHA) and TES-immunized and challenged(TES-V&C) groups were 61.5 and 83.3% and those of the other groups were all 100%. At 1 week after challenge, the lesion scores of TES-CHA group(4.0) was the highest of all experimental groups. Those of DEX and controlchallenged( CON-CHA) groups were 2.8, and those of all V&C groups were 2.4. During 1 and 2 weeks after immunization, the body weight gains of TES groups were severe low(61.6-82.2g and 189.6-260.4g). During 1 and 2 weeks after challenge, the body weight gains of all CHA groups were lower than those of not challenged groups. But, those of all V AC groups were not different from those of not immunized groups. At 4- and 6-weeks old, the weight of the bursa of Fabricius and thymus in the chicken of all TES groups were lower than those of all control (CON) and DEX groups. Therefore, testosterone propionate acted as immunosuppressive drug. Also, it was thought that the chicken affected a little humoral immunity to E tenella.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.2
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• pp.183-193
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• 2009

Purpose: Rotaviruses, noroviruses, astroviruses, and enteric adenoviruses cause acute gastroenteritis (AGE) in children. Some children with AGE have afebrile convulsions associated with viral gastroenteritis. The purpose of this study was to detect and genotype viruses from children with AGE or benign infantile seizures associated with mild gastroenteritis (BIS-MG). Methods: Between August 2004 and June 2005, 311 children with AGE were included. Four viral agents, including rotavirus, norovirus, astrovirus, and adenovirus, were analyzed from stool specimens of each patient using the latex agglutination method, enzyme immunoassay, and reverse transcriptase polymerase chain reaction. Genotyping of each virus was performed in 217 of the 311 children. Results: Among 217 children (male, 121; female, 96; mean age, 20.6${\pm}$15.4 months), rotavirus was detected in 109 (50.2%), norovirus in 28 (12.9%), adenovirus in 13 (6.0%), and astrovirus in 2 children (0.9%). Genotyping of rotavirus revealed positive results in 97 children; P[8]G3 in 36, P[4]G2 in 21, P[6]G4 in 10, P[4]G4 in 9, P[8]G9 in 6, P[8]G1 in 6, P[4]G3 in 4, P[4]G9 in 3, and P[6]G2 in 2. Genotyping of norovirus showed GII-4 in 27 of 28 children and GII-6 in 1 child. Sixteen children were diagnosed with BIS-MG. Rotavirus was detected in 13 of 16 children with BIS-MG, and norovirus in 2 children. Genotyping of rotavirus detected in children with BIS-MG revealed P[8]G3 in 6 children, P[4]G2 in 2 children, and P[4]G9 in 1 child. Conclusion: Analysis of viruses from stool specimens indicates that both rotavirus and norovirus are the main viruses related to BIS-MG in children.

• Pediatric Infection and Vaccine
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• v.11 no.2
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• pp.176-182
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• 2004

Purpose : The etiologic agents of aseptic meningitis remain mostly unknown due to difficulty of viral culture and identification. There was an outbreak of aseptic meningitis in northern area of Seoul from June to August, 2002. We report the clinical features, laboratory data and causative viruses on 196 children with aseptic meningitis during this period. Methods : We retrospectively studied about clinical manifestations and laboratory findings 196 patients diagnosed as aseptic meningitis at Sanggye-Paik hospital. Virus isolation and serotype identification were performed by cell culture and reverse transcription polymerase chain reaction(RT-PCR) of the cerebrospinal fluid. Results : The male to female ratio was 1.39 : 1 and the mean age was 5.8+3 years. The clinical manifestations were fever, headache and vomiting. It occurred mostly in June, July and August. The numbers of peripheral blood leukocytes were $4,800{\sim}24,360/mm^3$. On cerebrospinal fluid examinations, leukocytes were in range of 10~2,000(mean 105)/$mm^3$, protein level in range of 15~171(mean 41.4) mg/dL and glucose level from 16~97(mean 57.9) mg/dL. Viral culture of cerebrospinal fluid showed 3 cases of Echovirus 9, 1 case of 25 and 30. In stool culture, 2 cases of Echovirus 6, 2 cases of Echovirus 13 and 1 case of Echovirus 30 were isolated. Conclusion : The etiologic viruses of the aseptic meningitis in northern area of Seoul in 2002 are presumed to be Echovirus 6, 9, 13, 25, 30.

• Tuberculosis and Respiratory Diseases
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• v.72 no.6
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• pp.493-500
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• 2012

Background: This study investigated the clinical characteristics and risk factors of the severity of pandemic influenza A (H1N1) 2009 infection in pediatric patients in Busan and Gyeongsangnam-do. Methods: Cases of influenza A (H1N1) 2009 in patients under the age of 18 years, confirmed by reverse transcription polymerase chain reaction, at Pusan National University Hospital and Pusan National University Yangsan Hospital from the last week of August 2009 through the last week of February 2010 were retrospectively analyzed. Results: Of the 3,777 confirmed cases of influenza A (H1N1) 2009, 2,200 (58.2%) were male and 1,577 (41.8%) were female. The average age of the patients was $8.4{\pm}4.8$ years. The total cases peaked during 44th to 46th week. Most of the patients were in the 5- to 9-year-old age group. Oseltamivir was administered to 2,959 (78.3%) of the patients. 221 patients (5.9%) were hospitalized, age an average of $6.7{\pm}4.5$ years. The average duration of hospitalization was $7.4{\pm}5.6$ days. One hundred cases (45.2%) had pneumonia. Risk factors for hospitalization included male gender, <2 years of age, and underlying disease. Children with asthma were at very high risk of hospitalization, over 20 times the non-asthmatic children (odds ratio [OR], 21.684; confidence interval [CI], 13.295~39.791). Likewise the children with neurologic deficits faced a 16 times higher risk (OR, 15.738; CI, 7.961~31.111). Ten of the patients (4.5%) were admitted to the intensive care unit, and eight (3.6%) required mechanical ventilation. Conclusion: Of the pediatric patients with pandemic influenza A (H1N1) 2009, most of the patients were in the 5- to 9-year-old age group. Risk factors for hospitalization included male gender, <2 years of age, and underlying disease. The most common complication was pneumonia. The very high risk of severe morbidity in children with asthma or neurologic disease shows the critical importance of targeted vaccine coverage, special awareness and swift care by both guardians and primary care providers.

• Clinical and Experimental Pediatrics
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• v.56 no.1
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• pp.26-31
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• 2013

Purpose: Lymphocyte subset recovery is an important factor that determines the success of hematopoietic stem cell transplantation (HSCT). Temporal differences in the recovery of lymphocyte subsets and the factors influencing this recovery are important variables that affect a patient's posttransplant immune reconstitution, and therefore require investigation. Methods: The time taken to achieve lymphocyte subset recovery and the factors influencing this recovery were investigated in 59 children who had undergone HSCT at the Department of Pediatrics, The Catholic University of Korea Seoul St. Mary's Hospital, and who had an uneventful follow-up period of at least 1 year. Analyses were carried out at 3 and 12 months post-transplant. An additional study was performed 1 month post-transplant to evaluate natural killer (NK) cell recovery. The impact of pre- and post-transplant variables, including diagnosis of Epstein-Barr virus (EBV) DNAemia posttransplant, on lymphocyte recovery was evaluated. Results: The lymphocyte subsets recovered in the following order: NK cells, cytotoxic T cells, B cells, and helper T cells. At 1 month post-transplant, acute graft-versus-host disease was found to contribute significantly to the delay of $CD16^+/56^+$ cell recovery. Younger patients showed delayed recovery of both $CD3^+/CD8^+$ and $CD19^+$ cells. EBV DNAemia had a deleterious impact on the recovery of both $CD3^+$ and $CD3^+/CD4^+$ lymphocytes at 1 year post-transplant. Conclusion: In our pediatric allogeneic HSCT cohort, helper T cells were the last subset to recover. Younger age and EBV DNAemia had a negative impact on the post-transplant recovery of T cells and B cells.

• Pediatric Infection and Vaccine
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• v.20 no.2
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• pp.89-97
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• 2013

Purpose: This retrospective study was performed to identify the clinical characteristics of influenza B infection and compare to influenza A infection. Methods: Medical records of patients diagnosed with influenza using a multiplex PCR test, admitted to Seoul St. Mary's Hospital, during the 2011-2012 influenza season were analyzed. Clinical and laboratory characteristics of influenza B patients were investigated and compared with those of influenza A patients. Results: A total of 145 influenza patients were enrolled during this study period. Among these, 66 and 78 patients were diagnosed with influenza A and B, respectively, and 1 patient was diagnosed with co-existing influenza A and B. Cough (88.2%), rhinorrhea (77.1%) and sputum (60.4%) were the most common symptoms among these influenza patients, and most were diagnosed with upper respiratory infection (31.9%) or lower respiratory infection (49.3%). In comparison to influenza A patients, influenza B patients were older ($4.7{\pm}4.1$ years vs. $3.3{\pm}2.5$ years, P=0.016), and the number of fever days before hospitalization were longer (3.0 days vs. 2.5 days, P=0.043). While sore throat (10.3% vs. 1.5%, P=0.039) and vomiting (20.5% vs. 6.1%, P=0.012) were more common in influenza B patients than in influenza A patients, other clinical and laboratory characteristics were not significantly different between the two groups. Conclusions: No significant differences in clinical and laboratory perspectives were manifested in influenza A and B infections. Preventive measures should be emphasized over treatment in influenza B due to prolonged fever duration before admission.

• Korean Journal of Veterinary Research
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• v.26 no.1
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• pp.87-92
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• 1986

The present surveys were conducted in attempts to investigate the health situation of horses in Korea through mass-screening the samples serologically, bacteriologically and clinically. A total of 575 horses were sampled randomly, comprising 126 from the Korean Horse Affairs Association, 288 from the Korean Equestrian Federation and 161 from the Jeju ponies. Each of the samples taken was tested for diagnoses of 18 horse diseases including African horse sickness. Summarised below are the results obtained from this surveys. 1. From results of the serological survey it is evident that Korea is currently free from African horse sickness, dourine, glanders, vesicular stomatits, equine piroplasmosis, equine viral arteritis, Venezuelan encephalomyelitis and contagious equine metritis. Constant vigilence with strengthened quarantine measures is thus vital for maintaining freedom of any those diseases in Korea. 2. No clinical case was observed with any of signs or symptoms of infectious lymphangitis, anthrax and infestations with ringworm, mange or scab. However, continuous follow-up is required for establishing the evidence of no occurrence of the diseases in Korea. 3. One case of seropositive to equine infectious anemia may fully justify systematic and regular testings for the whole population of horse in Korea. 4. It is manifested that equine rhinopneumonitis, Japanese encephalitis and Getah virus infection are well established in Korea, together with the presence of equine infectious abortion(Salmonella abortus equi). This strongly entails preventive precautions before entry into Korea for the horses participating in the 1986 Asian Games and the 1988 Seoul Olympics.