• 한국임상수의학회지
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• 제36권4호
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• pp.185-189
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• 2019

Respiratory pathogens of calves including bovine parainfluenza type 3 virus (BPI3V), bovine respiratory syncytial virus (BRSV), infectious bovine rhinotracheitis virus (IBRV) and Mycoplasma spp is well-known for winter pathogens. However, there are no studies about summer pneumonia pathogens of calves in Korea. The aim of this study was to detect respiratory pathogens from calves with summer pneumonia. Eighty calves from 5 regions were chosen and their nasal swabs were used to detect respiratory pathogens with real-time PCR. Mycoplasma spp was major primary respiratory pathogens in calves with summer pneumonia. Although, the detection rates of respiratory viruses were very low, serological assays showed that respiratory viruses exist widely in farms.

• BMB Reports
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• 제44권4호
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• pp.232-237
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• 2011

Human respiratory syncytial virus (HRSV) is a major cause of upper and lower respiratory tract illness in infants and young children worldwide. Despite its importance as a respiratory pathogen, there is currently no licensed vaccine for prophylaxis of HRSV infection. There are several hurdles complicating the development of a RSV vaccine: 1) incomplete immunity to natural RSV infection leading to frequent re-infection, 2) immature immune system and maternal antibodies of newborn infants who are the primary subject population, and 3) imbalanced Th2-biased immune responses to certain vaccine candidates leading to exacerbated pulmonary disease. After the failure of an initial trial featuring formalin-inactivated virus as a RSV vaccine, more careful and deliberate efforts have been made towards the development of safe and effective RSV vaccines without vaccine-enhanced disease. A wide array of RSV vaccine strategies is being developed, including live-attenuated viruses, protein subunit-based, and vector-based candidates. Though licensed vaccines remain to be developed, our great efforts will lead us to reach the goal of attaining safe and effective RSV vaccines in the near future.

• Clinical and Experimental Pediatrics
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• 제61권6호
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• pp.180-186
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• 2018

Purpose: Despite the availability of molecular methods, identification of the causative virus in children with acute respiratory infections (ARIs) has proven difficult as the same viruses are often detected in asymptomatic children. Methods: Multiplex reverse transcription polymerase chain reaction assays were performed to detect 15 common respiratory viruses in children under 15 years of age who were hospitalized with ARI between January 2013 and December 2015. Viral epidemiology and clinical profiles of single virus infections were evaluated. Results: Of 3,505 patients, viruses were identified in 2,424 (69.1%), with the assay revealing a single virus in 1,747 cases (49.8%). While major pathogens in single virus-positive cases differed according to age, human rhinovirus (hRV) was common in patients of all ages. Respiratory syncytial virus (RSV), influenza virus (IF), and human metapneumovirus (hMPV) were found to be seasonal pathogens, appearing from fall through winter and spring, whereas hRV and adenovirus (AdV) were detected in every season. Patients with ARIs caused by RSV and hRV were frequently afebrile and more commonly had wheezing compared with patients with other viral ARIs. Neutrophil-dominant inflammation was observed in ARIs caused by IF, AdV, and hRV, whereas lymphocyte-dominant inflammation was observed with RSV A, parainfluenza virus, and hMPV. Monocytosis was common with RSV and AdV, whereas eosinophilia was observed with hRV. Conclusion: In combination with viral identification, recognition of virus-specific clinical and laboratory patterns will expand our understanding of the epidemiology of viral ARIs and help us to establish more efficient therapeutic and preventive strategies.

• Pediatric Infection and Vaccine
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• 제6권1호
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• pp.131-135
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• 1999

신생아 시기에 호흡기 바이러스 감염은 증상이 다양하게 나타나 진단하기가 힘든 면이 있으나 본 증례와 같이 뚜렷한 호흡기 증상이 있는 경우 적극적인 진단과 치료가 필요하다고 사료되며 고위험군 환자에게 RSV 유행 시기에 앞서 예방이 중요하다고 생각한다.

• International Journal of Advanced Culture Technology
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• 제10권4호
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• pp.316-321
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• 2022

Since 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly, infecting millions of people worldwide. On March 11, 2020, the World Health Organization declared coronavirus disease (COVID-19) a pandemic owing to the worldwide spread of SARS-CoV-2, which created an unprecedented burden on the global healthcare system. In this context, there are increasing concerns regarding co-infections with other respiratory viruses, such as the influenza virus. In this study, clinical data of patients infected with SARS-CoV-2 and other respiratory viruses were compared with patients infected with SARS-CoV-2 alone. The hematology and blood biochemistry results of 178 patients infected with SARS-CoV-2 , who were tested on admission, were retrospectively reviewed. In patients with SARS-CoV-2 and adenovirus co-infection, C-reactive protein levels were elevated on admission, whereas lactate dehydrogenase (LDH), prothrombin time, international normalized ratio, activated partial thromboplastin clotting time, and bilirubin values were all within the normal range. Moreover, patients with SARS-CoV-2 and human bocavirus co-infection had low LDH and high bilirubin levels on admission. These findings reveal the clinical features of respiratory virus and SARS-CoV-2 co-infections and support the development of appropriate approaches for treating patients with SARS-CoV-2 and other respiratory virus co-infections.

• 한국동물위생학회지
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• 제32권1호
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• pp.19-25
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• 2009

Porcine reproductive and respiratory syndrome (PRRS) virus is the etiological agent of diseases characterized by reproductive losses in sows and respiratory disorders in piglets. The PRRS virus is a small enveloped virus containing a positive-sense, single-stranded RNA genome. In the present study, ORF6 gene of Korean PRRS virus isolate, CNV, was cloned and expressed in baculovirus expression system. The ORF6 gene and expressed protein in the recombinant virus were confirmed by PCR/indirect fluorescence antibody (IFA) test and Western blotting, respectively. The recombinant protein with a molecular weight of approximately 24KDa was confirmed by Western blotting using His6 and PRRS virus-specific antiserum. Expressed ORF6 protein was applied for IFA to detect antibody against PRRS virus using field porcine sera. However, the sensitivity and specificity of developed IFA using expressed ORF6 protein were considerably low compared to those of commercial ELISA kit. This results suggest that IFA using expressed ORF6 protein could not be used as a diagnostic test for PRRS virus infection without further improvements.

• Tuberculosis and Respiratory Diseases
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• 제80권4호
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• pp.358-367
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• 2017

Background: Bacterial pneumonia occurring after respiratory viral infection is common. However, the predominant bacterial species causing pneumonia secondary to respiratory viral infections other than influenza remain unknown. The purpose of this study was to know whether the pathogens causing post-viral bacterial pneumonia vary according to the type of respiratory virus. Methods: Study subjects were 5,298 patients, who underwent multiplex real-time polymerase chain reaction for simultaneous detection of respiratory viruses, among who visited the emergency department or outpatient clinic with respiratory symptoms at Ulsan University Hospital between April 2013 and March 2016. The patients' medical records were retrospectively reviewed. Results: A total of 251 clinically significant bacteria were identified in 233 patients with post-viral bacterial pneumonia. Mycoplasma pneumoniae was the most frequent bacterium in patients aged <16 years, regardless of the preceding virus type (p=0.630). In patients aged ${\geq}16years$, the isolated bacteria varied according to the preceding virus type. The major results were as follows (p<0.001): pneumonia in patients with influenza virus (type A/B), rhinovirus, and human metapneumovirus infections was caused by similar bacteria, and the findings indicated that Staphylococcus aureus pneumonia was very common in these patients. In contrast, coronavirus, parainfluenza virus, and respiratory syncytial virus infections were associated with pneumonia caused by gram-negative bacteria. Conclusion: The pathogens causing post-viral bacterial pneumonia vary according to the type of preceding respiratory virus. This information could help in selecting empirical antibiotics in patients with post-viral pneumonia.

• 대한수의학회지
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• 제50권3호
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• pp.205-211
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• 2010

Fifty young calves, about five to six months old purchased from nation-wide were investigated with the prevelance of neutralizing antibody (Ab) of infectious bovine rhinotracheitis virus (IBRV), parainfluenza 3 virus ($PI_{3}V$), bovine viral diarrhea virus (BVDV) and bovine respiratory syncytial virus (BRSV). The positive detection ratio of neutralizing Ab against IBRV was only 3% and two of positive samples showed low antibody titer (below 2). Ab against BRSV showed 48% of positive ratio and among 24 positive samples, antibody titer of 23 samples were below 3. But in the case of BVDV, 68% of samples were positive and 23 samples appeared to possess high antibody titer, above 4 and the antibody titer of five samples were above 8. The highest positive result came from $PI_{3}V$. The positive ratio in the samples investigated in this study was 72%, but the antibody titer of positive samples were generally below 3 (77.8% in positive samples).

• Clinical and Experimental Pediatrics
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• 제55권9호
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• pp.309-315
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• 2012

Human respiratory syncytial virus (HRSV) is a major cause of severe respiratory tract illnesses in infants and young children worldwide. Despite its importance as a respiratory pathogen, there is currently no licensed vaccine for HRSV. Following failure of the initial trial of formalin-inactivated virus particle vaccine, continuous efforts have been made for the development of safe and efficacious vaccines against HRSV. However, several obstacles persist that delay the development of HRSV vaccine, such as the immature immune system of newborn infants and the possible Th2-biased immune responses leading to subsequent vaccine-enhanced diseases. Many HRSV vaccine strategies are currently being developed and evaluated, including live-attenuated viruses, subunit-based, and vector-based candidates. In this review, the current HRSV vaccines are overviewed and the safety issues regarding asthma and vaccine-induced pathology are discussed.

• 한국동물위생학회지
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• 제41권4호
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• pp.263-269
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• 2018

Developing drugs targeting respiratory pathogen is essential to control respiratory diseases. Many experiments have been performed under in vivo situation. However, in vivo experiments have economical and ethical issues. The objective of this study was to determine the possibility of developing an ex vivo lung culture system with possible application for respiratory infection studies. After isolating lungs from naïve pigs, agarose-inflated lung tissues were prepared and sliced manually. These sliced lung tissues were then subsequently placed on 24-well plates. Eight different combinations of media were used to determine the optimum ex vivo lung culture condition. In addition, lung tissues were infected with porcine reproductive and respiratory syndrome (PRRS) virus at a titer of $1{\times}10^4\;TCID_{50}/mL$. Virus growth was confirmed by titration in MARC-145 cells at 2, 4, 6 days post infection (dpi). We found that ex vivo lung culture in physiological environment was not media specific based on histopathology and cytotoxicity. However, under virus-infected condition, thickened alveolar walls in the lung tissues and stable virus titers at 2, 4, 6 dpi were shown in F12K medium suggesting that it was useful for tissue maintenance and virus infection using PRRS virus infected lung tissues. The present study shows the possibility of using porcine ex vivo lung model for respiratory infection studies.