• The Journal of Korean Society of Virology
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• v.28 no.3
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• pp.247-265
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• 1998

To determine the sequence and expression of the VP7 gene of Korean isolates (CAU-9), viral RNA was purified and used for cDNA amplification by RT-PCR. The VP7 cDNA was cloned, sequenced, and expressed using baculovirus expression system. The result showed that the sequence homologies CAU-9 compared with foreign isolated strains Wa, 417, TMC-II, 95B and SA11 were ranged from 74.0% to 95.1 % of nucleotide sequence and 35% to 43% of amino acid sequence, respectively. High homology of CAU-9 was observed in Japanease isolates 417 (nucleotide sequence homology was 95.1% and amino acid sequence homology was 43%). To express VP7 gene, the VP7 cDNA was cloned into pCR-Bac vector and inserted into the genome of baculovirus adjacent to the polyhedrin promoter by cotransfection of Spodoptera frugiperda (Sf9) insect cells with wild type baculovirus DNA. In antigenic analysis of Sf9 cells inoculated with the recombinant VP7, immunofluorescence assay revealed positive for viral antigens. In metabolic labeling of Sf9 cell lysates infected with recombinant baculoviruses, it was revealed that the protein of 34 kDa was expressed. The limited study of expressed VP7 protein inoculated with guinea pigs failed to elicit neutalizing antibody. As a results, the sequence analysis and expression of VP7 protein of rotavirus CAU-9 isolated from an infant in Korea could permit the conformation and development of virus like particles which may be useful in designing vaccine strategy.

• Pediatric Infection and Vaccine
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• v.19 no.2
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• pp.61-70
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• 2012

Purpose: This study was performed to compare the clinical characteristics of 2009 pandemic influenza A(H1N1) [A(H1N1) pdm09] and seasonal influenza A infection in the pediatric cancer patients. Methods: A retrospective review was performed in the pediatric cancer patients who had confirmed A(H1N1)pdm09 infection at Samsung Medical Center from August 2009 to February 2010. For the comparison, the medical records of pediatric cancer patients with seasonal influenza A from January 2000 to May 2009 were reviewed retrospectively. Results: Eighty-two A(H1N1)pdm09 infections were confirmed in the pediatric cancer patients. Ten patients (12.2%) developed complicated clinical course by lower respiratory infections or extrapulmonary infections; 4 pneumonia, 1 bronchitis, 1 pericarditis with pneumonia, 1 encephalitis with pneumonia, 2 meningitis and 1 pericarditis. Three patients received mechanical ventilator and ICU care. Three pediatric cancer patients (3.7%) died. The risk factors related to complicated A(H1N1)pdm09 infections were date of infection (44-45th week 2009) and nosocomial infection. When comparing with previous seasonal influenza A infections, more prompt and aggressive antiviral therapy was given in A(H1N1)pdm09 infections. Conclusion: The A(H1N1)pdm09 infections caused a various clinical manifestations including fatal cases in pediatric cancer patient during pandemic season. There was no significant difference in clinical course between influenza A(H1N1)pdm09 and seasonal influenza A infections except the antiviral treatment strategy.

• IMMUNE NETWORK
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• v.11 no.1
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• pp.79-94
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• 2011

Background: Dendritic cell (DC)-based vaccines are currently being evaluated as a novel strategy for tumor vaccination and immunotherapy. However, inducing long-term regression in established tumor-implanted mice is difficult. Here, we show that deoxypohophyllotoxin (DPT) induces maturation and activation of bone marrow-derived DCs via Toll-like receptor (TLR) 4 activation of MAPK and NF-${\kappa}B$. Methods: The phenotypic and functional maturation of DPT-treated DCs was assessed by flow cytometric analysis and cytokine production, respectively. DPT-treated DCs was also used for mixed leukocyte reaction to evaluate T cell-priming capacity and for tumor regression against melanoma. Results: DPT promoted the activation of $CD8^+$ T cells and the Th1 immune response by inducing IL-12 production in DCs. In a B16F10 melanoma-implanted mouse model, we demonstrated that DPT-treated DCs (DPT-DCs) enhance immune priming and regression of an established tumor in vivo. Furthermore, migration of DPT-DCs to the draining lymph nodes was induced via CCR7 upregulation. Mice that received DPT-DCs displayed enhanced antitumor therapeutic efficacy, which was associated with increased IFN-${\gamma}$ production and induction of cytotoxic T lymphocyte activity. Conclusion: These findings strongly suggest that the adjuvant effect of DPT in DC vaccination is associated with the polarization of T effector cells toward a Th1 phenotype and provides a potential therapeutic antitumor immunity.

• Pediatric Infection and Vaccine
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• v.24 no.2
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• pp.87-94
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• 2017

Purpose: The inappropriate prescription of antibiotics in children with upper respiratory tract infection (URTI) is common. This study evaluated the factors that influence antibiotics use in hospitalized children with viral URTI confirmed by reverse transcriptase-polymerase chain reaction (RTPCR) assay. Methods: The medical records of admitted patients who performed RT-PCR assay for respiratory virus pathogens from January 2013 to November 2014 were examined. The demographic and clinical features were compared between patients who were administered antibiotics at admission and those who were not. We also investigated differences between children who continued antibiotics and those who stopped antibiotics after a viral pathogen was identified. Results: In the total 393 inpatients, the median age was 23 months (interquartile range, 13 to 41.3 months). Antimicrobial agents were prescribed in 79 patients (20.1%) at admission. Patients with acute otitis media (AOM) had higher rates of antibiotics prescription than those without AOM (48.1% vs. 2.2%, P<0.001), with an adjusted odds ratio of 91.1 (95% confidence interval, 30.5 to 271.7). Level of high-sensitivity C-reactive protein and the proportion of acute rhinosinusitis were also significantly associated with antibiotics use (P<0.001). Among the 44 patients with viruses identified using the RT-PCR method during hospitalization, antibiotic use was continued in 28 patients (63.6%). AOM was statistically associated with continued antibiotic use in the patients (P=0.002). Conclusions: Although the respiratory virus responsible for URTI etiology is identified, clinicians might not discontinue antibiotics if AOM is accompanying. Therefore, careful diagnosis and management of AOM could be a strategy to reduce unjustified antibiotic prescriptions for children with URTI.

• Pediatric Infection and Vaccine
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• v.30 no.2
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• pp.55-61
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• 2023

Purpose: Urinary tract infections (UTIs) pose a significant disease burden in children. This study aims to determine whether a short-course regimen is non-inferior to a standard-course regimen in children with UTIs without complication and presence of bacteremia, and to define, in the optimal way possible, the term "short-course" in this context. Methods: We conducted a rapid systematic review of research up to April 2021 in PubMed, Embase, and Cochrane databases. We included studies that compared clinical outcomes in pediatric UTIs treated with short-course(≤4 days) or standard (≥5-7 days) courses. Results: Our analysis suggests that short-course regimes have equivalent efficacy to standard-course regimens, with similar clinical cure rates and recurrence rates. All 10 studies comparing the clinical cure rates of short- and standard-course regimens reported comparable outcomes. The study evaluating renal scarring indicated no inferiority of short-course regimens compared to standard-course ones. Regarding UTI relapse, 8 out of 10 studies reported no significant difference in outcomes between short- and standard-course regimens. Conclusions: Our results purpose that short-course UTI regimens of 6 days or less are just as effective as standard-term regimens of 7 days or more in terms of infection cure and prevention of recurrence. Considering the equivalent rates of clinical cure and relapse between short- and standard-course regimens, it could be inferred that short-course regimens might be a more optimal strategy for managing pediatric UTIs without increasing the risk of complications.

• Clinical and Experimental Pediatrics
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• v.51 no.10
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• pp.1077-1084
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• 2008

Purpose : Despite the seriousness of bacterial meningitis in children, there is little information on the incidence, causative organisms, mortality rate and age distribution. We studied the frequency by age group and causal pathogens, and clinical characteristics in children with bacterial meningitis in the private sector in Korea. Methods : The medical records containing the data on bacterial meningitis patients under 18 years of age confirmed by cerebrospinal fluid (CSF) findings were retrospectively analyzed from September, 1993 to August, 2006 at Ewha Womans University Mokdong Hospital. Results : Eighty-one cases of bacterial meningitis were observed. Overall the most common organism was Streptococcus agalactiae (group B streptococcus, GBS) (30 cases, 37.0%) followed by Haemophilus influenzae (22 cases, 27.2%), Streptococcus pneumoniae (12 cases, 14.8%), Escherichia coli (3 cases, 3.7%), Neisseria meningitidis (1 case, 1.2%) and others (13 cases, 16.0%). In neonates and young infants under 2 months, the most common organism was GBS. In children between 3 months, and 5 years, the most common organism was H. influenzae. S. pneumoniae was the most common organism in children over 5 years of age. Thirty-one patients (38.3%) had complications. Of all ages, the mortality rate of bacterial meningitis markedly decreased compared with the previously reported rate. Conclusion : In neonates, GBS meningitis was most common. The frequency of H. influenzae meningitis decreased after the introduction of H. influenzae type b vaccination. A strategy for the prevention of GBS meningitis in neonates should be established. The influence of the pneumococcal conjugate vaccine on S. pneumoniae meningitis should be studied.

• Pediatric Infection and Vaccine
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• v.23 no.3
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• pp.180-187
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• 2016

Purpose: This study described the post-exposure prophylaxis (PEP) and secondary varicella infection in children inadvertently exposed to varicella zoster virus (VZV) in the hospital. Methods: We retrospectively analyzed data from patients with VZV infection who were initially not properly isolated, as well as children exposed to VZV at the Seoul National University Children's Hospital between January 2010 and December 2015. The PEP measures were determined by the presence of immunity to VZV and immunocompromising conditions. Patient clinical information was reviewed via medical records. Results: Among 147 children hospitalized between 2010 and 2015, 13 inadvertent exposures were notified due to VZV infection. Five index children had a history of VZV vaccination. Eighty-six children were exposed in multi-occupancy rooms and 62.8% (54/86) were immune to VZV. The PEP measures administered to 27 exposed patients included varicella zoster immunoglobulin and VZV vaccination. Four children developed secondary varicella, which was linked to a single index patient, including one child who did not receive PEP and three of the 27 children who received PEP. The rates of secondary varicella and prophylaxis failure were 4.7% (4/85) and 11.1% (3/27), respectively. The secondary varicella rates were 1.9% (1/54) and 9.7% (3/31) among immunocompetent and immunocompromised children, respectively. Conclusions: Delayed diagnosis of VZV infection can lead to unexpected exposure and place susceptible children and immunocompromised patients at risk for developing varicella. The appropriateness of the current PEP strategy based on VZV immunity may require re-evaluation.

• Pediatric Infection and Vaccine
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• v.13 no.2
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• pp.137-146
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• 2006

Purpose : A regional lymphadenitis is the most frequent adverse reaction of BCG. In order to find out developmental factors and establish a strategy of management, we investigated the clinical courses of children with lymphadenitis following BCG on the aspect of BCG strains, suppurative rates according to the sizes of lymph node and the clinical difference with or without treatment. Methods : From January 1997 to June 2004, 52 children less than 24 month-age-old diagnosed as BCG lymphadenitis in Department of Pediatrics, St. Vincent's Hospital, The Catholic University of Korea were enrolled. The type of BCG strain, place of vaccination, location and size of lymphadenitis were assessed with medical records, retrospectively. Finally, we analysed the correlations between BCG strains or the sizes of lymph node and natural remission or suppuration. Results : The first detected mean age of BCG lymphadenitis was 5.5 month-age. The larger of the measurement was at the first visiting, the younger of age that was first presented. The most frequent location was the same sided axillary region of BCG injection. Among 52 subjects, 46 cases(88.5%) were vaccinated with intradermal Pastuer strain, and only 5 cases(9.6%) were done with percutaneous multipunctured Tokyo strain. Twenty eight cases(53.8%) were regressed naturally, otherwise 24 cases(46.2%) were suppurated. The larger those were sized, the higher freqeuncies those were suppurated on, significantly. Treatment with medications could not prevent the suppuration and could not shorten the healing periods. Conclusion : We predict that there are differences between the occurrent rate of BCG lymphadenitis and BCG strains or methods. Treatment with medication is not recommended owing to its ineffectiveness. Especially, in case of non-suppurative lymphadenitis should be onlyless influence on the tuberculin skin test, cause less adverse reactions, and is inexpensive. observed without treatment, because it could be regressed naturally. An ideal BCG makes a scar, We should make an effort to choose the best BCG strain that can fulfill such requirements.