• Clinical and Experimental Pediatrics
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• v.54 no.10
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• pp.405-408
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• 2011

Purpose: In autumn 2009, the swine-origin influenza A (H1N1) virus spread throughout South Korea. The aims of this study were to determine the clinical characteristics of children infected by the 2009 H1N1 influenza A virus, and to compare the rapid antigen and realtime polymerase chain reaction (PCR) tests. Methods: We conducted a retrospective review of patients ${\geq}18$ years of age who presented to Soonchunhyang University Hospital in Seoul with respiratory symptoms, including fever, between September 2009 and January 2010. A real-time PCR test was used to definitively diagnose 2009 H1N1 influenza A infection. Medical records of confirmed cases were reviewed for sex, age, and the time of infection. The decision to perform rapid antigen testing was not influenced by clinical conditions, but by individual factors such as economic conditions. Its sensitivity and specificity were evaluated compared to real-time PCR test results. Results: In total, 934 patients tested positive for H1N1 by real-time PCR. The highest number of patients (48.9%) was diagnosed in November. Most patients (48.2%) were aged between 6 and 10 years. Compared with the H1N1 real-time PCR test results, the rapid antigen test showed 22% sensitivity and 83% specificity. Seventy-eight patients were hospitalized for H1N1 influenza A virus infection, and fever was the most common symptom (97.4%). Conclusion: For diagnosis of 2009 H1N1 influenza A virus infection, the rapid antigen test was inferior to the real-time PCR test in both sensitivity and specificity. This outcome suggests that the rapid antigen test is inappropriate for screening.

• Journal of Microbiology and Biotechnology
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• v.22 no.8
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• pp.1165-1169
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• 2012

In April 2009, the H1N1 pandemic influenza virus emerged as a novel influenza virus. The aim of this study was to compare the performances of several molecular assays, including conventional reverse transcription polymerase chain reaction (RT-PCR), two real-time reverse transcription (rRT)-PCRs, and two multiplex RTPCRs. A total of 381 clinical specimens were collected from patients (223 men and 158 women), and both the Seeplex RV7 assay and rRT-PCR were ordered on different specimens within one week after collection. The concordance rate for the two methods was 87% (332/381), and the discrepancy rate was 13% (49/381). The positive rates for the molecular assays studied included 93.1% for the multiplex Seeplex RV7 assay, 93.1% for conventional reverse transcription (cRT)-PCR, 89.7% for the multiplex Seeplex Flu ACE Subtyping assay, 82.8% for protocol B rRT-PCR, and 58.6% for protocol A rRT-PCR. Our results showed that the multiplex Seeplex assays and the cRT-PCR yielded higher detection rates than rRT-PCRs for detecting the influenza A (H1N1) virus. Although the multiplex Seeplex assays had the advantage of simultaneous detection of several viruses, they were time-consuming and troublesome. Our results show that, although rRT-PCR had the advantage, the detection rates of the molecular assays varied depending upon the source of the influenza A (H1N1)v virus. Our findings also suggest that rRT-PCR sometimes detected virus in extremely low abundance and thus required validation of analytical performance and clinical correlation.

• Archives of Pharmacal Research
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• v.17 no.6
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• pp.443-451
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• 1994

The binding characteristics of pirenzepine and oxomemazine to muscarinic receptor were studied to evaluate the selectivity of oxomemazine for the muscarinic receptor subtypes in rat cerebral microsomes. Equililbrium dissociation constant $(K_D){\;}of{\;}(-)[^3H]$quinuclidinyl benzilate$([^3H)QNB)$ determined from saturation isotherms was 64-pM. Analysis of the pirenzepine inghibition curve of [$^3H$]QNB binding to cerebral microsome indicatd the presence of two receptor subtypes with high $(K_1 = 16 nM, M_1 receptor)$two receptor subypes with about 20-fold difference in the affinity for high $(k_1 = 84nM, {\;} O_H receptor){\;} and {\;}low{\;} (K_1{\;} ={\;} 1.65\muM, {\;} O_L receptor$) affinity sites. The percentage populations of $M_1{\;} and M_3$, /TEX> receptors to the total receptors were 61 : 39, and those of $O_H{\;} and{\;} O_L$ receptors 39 : 61, resepectively. Both pirenzepine and oxomemazine increaed the $K_D$ value for $[^3H]QNB$ without affecting the binding site concentrations and Hii coefficient for the $[^3H]QNB$ without affecting the binding site concentractions and Hill coefficient for the [$^{3}$H]QNB binding. Oxomemazine had a 10-fold higher affinity at $M_1$ receptors than at $M_3$ receptors, and pirenzepine a 8-fold higher affinity at $O_H$ receptors were of $O_H$ receptors and 71% of $M_3$ receptors. However, $M_3$for oxomemazine and $O_H$for pirenzepine were composed of a uniform population. These results suggest that oxomemazine could be classified as a selective drug for $M_1$ receptors and also demonstrate that rat cerebral microsomes contain three different subtypes of $M_1{\;} M_3$ and the other site which is different from $M_1, {\;} M_2$, /TEX> receptors.

• Journal of Environmental Health Sciences
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• v.39 no.3
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• pp.230-238
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• 2013

Objectives: For our survey of the incidence of influenza viruses among respiratory viral infections in Seoul, we evaluated their prevalence among infectious acute respiratory viral patients in Seoul from 2010 to 2012 through regular surveillance. Methods: For influenza virus detection, we conducted real-time PCR analyses on 2,544 throat specimens collected from patients with respiratory viral infections in Seoul between 2010 and 2012. They were collected and then tested for the presence of influenza viruses through reverse transcription (RT) - polymerase chain reaction (PCR). Results: 19.1% (486/2,544) of the throat specimens were determined to be positive for influenza viruses. The incidences of influenza viral infection in the case of respiratory viral infections through regular surveillance in Seoul were 23.0% (212/923) in 2010, 6.4% (47/738) in 2011, and 25.7% (227/883) in 2012, and 10.8% (275/2,544) of type A, and 8.3% (211/2,544) type B influenza viruses. In addition, the greatest prevalence was in the 20-49 age group (51.6% ), which shows that influenza viruses constituted a major causative agent of acute respiratory viral infections. Conclusions: The distributions of influenza viruses and the epidemiologic patterns of the viral pathogen in acute respiratory viral infectious patients may provide potentially effective data for epidemiological studies in Seoul, Korea.

• Clinical and Experimental Pediatrics
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• v.54 no.3
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• pp.117-122
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• 2011

Purpose: Natural history and consequences of the novel 2009 influenza A H1N1(2009 H1N1) infection in immunocompromised pediatric patients are not yet fully understood. In this study, we investigated the clinical features and outcomes of the 2009 H1N1 infection in pediatric patients with hematological and oncological diseases. Methods: We retrospectively reviewed the medical records of 528 patients who had hematological and oncological diseases and who were treated at 7 referral centers located in the Yeungnam region. Among the 528 patients, 27 with definite diagnosis of 2009 H1N1 infection were the subjects of this study. All patients were divided into the following 3 groups: patients who were receiving chemotherapy (group 1), patients who were immunosuppressed due to a nonmalignant hematological disease (group 2), and patients who were off chemotherapy and had undergone their last chemotherapy course within 2 years from the influenza A pandemic (group 3). Results: All 28 episodes of 2009 H1N1 infection were treated with the antiviral agent oseltamivir ($Tamiflu^{(R)}$), and 20 episodes were treated after hospitalization. Group 1 patients had higher frequencies of lower respiratory tract infection and longer durations of fever and hospitalization as compared to those in group 2. Ultimately, all episodes resolved completely with no complications. Conclusion: These results suggest that early antiviral therapy did not influence the morbidity or mortality of pediatric patients with hematological and oncological diseases in the Yeungnam region of Korea after the 2009 H1N1 infection. However, no definite conclusions can be drawn because of the small sample size.

• Tuberculosis and Respiratory Diseases
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• v.68 no.6
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• pp.350-353
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• 2010

Here we report the first fatality caused by H1N1 influenza virus infection with acute respiratory distress syndrome in Korea. A 55-year-old man presented at our emergency department with dyspnea, fever, diffuse myalgia and malaise. Bilateral lung air-space consolidation was detected on his initial chest radiograph combined with severe hypoxemia. He was supported by mechanical ventilation and treated with antibiotics. A nasopharyngeal aspirate was positive for influenza A rapid antigen and oseltamivir was started on day 3 of admission. The nasal swab sample was positive for influenza H1N1 virus by real-time reverse-transcriptase polymerase chain reaction. Despite aggressive treatment, he had refractory hypoxemia and uncontrolled septic shock. On day 5 of admission he went into cardiac arrest and expired.

• Korean Journal of Veterinary Service
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• v.40 no.1
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• pp.15-20
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• 2017

A two-tube reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was designed for the rapid visual detection of the M gene of all subtypes of avian influenza virus (AIV) and the H5 gene of the H5 subtype of highly pathogenic AIV (HPAIV). The reaction carried out in two tubes in a single step at $58^{\circ}C$ for 40 min, and the assay results could be visually detected by using hydroxynaphthol blue dye. Using M or H5 gene-specific primers, the assay successfully detected all subtypes or H5 subtypes of AIVs, including the Korean representative H5N1 and H5N8 HPAIVs. The detection limit of the assay was approximately $10^{2.0}$ $EID_{50}/reaction$ for the M and H5 genes of H5N1 HPAIV, respectively, and was more sensitive than that of previously reported RT-LAMP and comparable to that of real-time RT-PCR. These results suggest that the present RT-LAMP assay, with its high specificity, sensitivity, and simplicity, will be a useful diagnostic tool for surveillance of currently circulating H5 HPAIVs and other subtypes of AIV in bird population, even in under-equipped laboratories.

• Tuberculosis and Respiratory Diseases
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• v.70 no.5
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• pp.397-404
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• 2011

Background: To evaluate chest CT findings of pandemic influenza A/H1N1 pneumonia without co-infection. Methods: Among 56 patients diagnosed with pandemic influenza A/H1N1 pneumonia, chest CT was obtained in 22 between October 2009 and Februrary 2010. Since two patients were co-infected with bacteria, the other twenty were evaluated. Predominant parenchymal patterns were categorized into consolidation, ground glass opacity (GGO), and mixed patterns. Distribution of parenchymal abnormalities was assessed. Results: Median age was 46.5 years. The CURB-65 score, which is the scoring system for severity of community acquired pneumonia, had a median of 1. Median duration of symptoms was 3 days. All had abnormal chest x-ray findings. The median number of days after the hospital visit that Chest CT was performed was 1. The reasons for chest CT performance were radiographic findings unusual for pneumonia (n=13) and unexplained dyspnea (n=7). GGO was the most predominant pattern on CT (n=13, 65.0%). Parenchymal abnormalities were observed in both lungs in 13 cases and were more extensive in the lower lung zone than the upper. Central and peripheral distributions were identified in ten and nine cases, respectively. One showed diffuse distribution. Peribronchial wall thickening was found in 16 cases. Centrilobular branching nodules (n=7), interlobular septal thickening (n=4), atelectasis (n=1), pleural effusion (n=5), enlarged hilar and mediastinal lymph nodes (n=6 and n=7) were also noted. Conclusion: Patchy and bilateral GGO along bronchi with predominant involvement of lower lungs are the most common chest CT findings of pandemic influenza A/H1N1 pneumonia.

• Tuberculosis and Respiratory Diseases
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• v.70 no.1
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• pp.28-35
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• 2011

Background: The aim of the study was to describe the characteristics, treatments, and outcomes of critically ill patients with pandemic Influenza A/H1N1 2009 at a major medical center in Korea. Methods: This retrospective observational study examined critically ill adult patients with pandemic Influenza A/H1N1 2009, who were admitted to the AMC between August and December 2009. Results: 27 patients with confirmed pandemic Influenza A/H1N1 2009 were admitted to the intensive care unit (ICU) at the Asan Medical Center (AMC). The median age (IQR) was 59 years (41~67), and 66.7% of the patients were older than 51 years. A total of 81.5% of the patients had 2 or more co-morbidities. The median time (IQR) from symptom onset to presentation was 2 days (1~4), and the median time from presentation to ICU admission was 0 days (0~1.5). All patients received oseltamivir (300 mg/day) and 13 patients received triple combination therapy (oseltamivir, amantadine, ribavirin). Twelve patients required mechanical ventilation on the first day of ICU admission. A total of 6 patients (22.2%) died within 28 days of admission. The patients who died had significantly higher acute physiology and chronic health evaluation (APACHE) II and sequential organ failure assessment (SOFA) scores at presentation. There were no significant differences in age, co-morbidities, or antiviral regimens between survivors and non-survivors. Conclusion: Critical illness related to pandemic Influenza A/H1N1 2009 was common in elderly patients with chronic co-morbidities. All patients were given high-dose oseltamivir or triple combination antiviral therapy. Nonetheless, patients with critical illnesses associated with pandemic Influenza A/H1N1 2009 had a death rate of 22.2%.

• Korean Journal of Bronchoesophagology
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• v.5 no.1
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• pp.49-54
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• 1999

The etiology of inverted papilloma(IP) remains unknown, but several studies have reported that Human Papillomavirus(HPV) may play a role in the pathogensis of sinonasal inverted papilloma(IP). And recent reports demonstrate the possible etiologic role of Epstein-Barr virus (EBV) in sinonasal IP. The aim of this study is to detect HPV and EBV in sinonasal IP, to examine the relationship between HPV subtype and sinonasal IP, to investigate the relation between HPV and EBV. We reviewed 30 cases of sinonasal IP(simple IP 19 cases, IP with dysplasia 8 cases, IP with squamous cell carcinoma 3 cases). Paraffin embedded archival tissue was used in this study. Detection of HPV, EBV were examined by in situ hybridization(ISH) using HPV type 6/11, 16/18, 31/33/35 DNA probe and EBER probe. The HPV was detected in 6(20%) out of 30 cases. The HPV 6/11 was dectected in 4 out of 19 cases of simple IP, HPV 16/18 in 1, HPV 31/33/35 in 1 out of 8 cases of IP with dysplasia respectively. The EBV was not detected in 30 cases. HPV may play a role in the pathogensis of sinonasal inverted papilloma. But EBV is not a etiopathologic factor to be considered in the development of sinonasal IP.