• Journal of Integrative Natural Science
• /
• v.4 no.4
• /
• pp.273-277
• /
• 2011

It's a threat for the public health that H1N1 (Influenza virus A) causes disease and transmits among humans. WHO (world health organization) declared that the infections caused by the new strain had reached pandemic proportions. The approved neuraminidase inhibitors (Zanamivir and Oseltamivir) and related investigative drug (BCX-1812) are potent, specific inhibitors of influenza A and B viruses. These drugs are highly effective to prevent influenza A and B infections. Early therapeutic use reduces illness duration and respiratory complications. Recently, we found one of the potent inhibitor of erystagallin A ($IC_{50}$ of 2.04 ${\mu}M$) for neuraminidase target, this inhibitor shows most similar structure to its natural substrate, sialic acid. Therefore, we chose 1l7f to get the receptor structure for docking study among many crystal structures. A docking study has been performed in Surflex-Dock module in SYBYL 8.1. In the present study, we attempt to compare the docking studies of pterocarpin and erystagallin A with neuraminidase receptor structure. In the previous report, the methoxy group of pterocarpin had H-bonding with Arg residues. The present docking results for erystagallin A showed the backbone of hydroxyl group shows significant H-bonding interactions with Arg152 and Arg292. The results showed that erystagallin A interacts more favorably with distinctive binding site rather than original active site. Therefore, we tried to reveal plausible binding mode and important amino acid for this inhibitor using docking and site id search calculations of Sybyl. The results obtained from this work may be utilized to design novel inhibitors for neuraminidase.

• Korean Journal of Veterinary Service
• /
• v.34 no.2
• /
• pp.117-123
• /
• 2011

This experiment was conducted to investigate the presence of recognized abortifacient viruses from aborted fetuses and stillborn piglets in cases of reproductive failure in sows by PCR. A total of 219 samples of aborted fetuses or stillborn piglets, submitted to the School of Veterinary Medicine of Kangwon National University between 2006 and 2009 May, were collected from 5 provinces in Korea. Abortifacient virus infections were detected in 82 (37.4%) out of 219 aborted fetuses or stillborn piglets as well as on 39 (40.2%) out of 97 pig farms. The major viral infections were porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV) and Aujesky's disease virus (ADV) for which 46 (21%), 19 (8.6%) and 16 (7.3%) were positive, respectively, with 9 fetuses had complicated infection of PCV2+PRRSV or ADV or both. And 8 (3.6%) for SIV, 3 (1.3%) for PPV and 1 (0.4%) for JEV were positive as minor viral infection. The results suggest that PCV2, PRRSV, ADV is apparently the most important viral infectious agents associated with fetal infection leading to abortion or stillbirth in Korea. SIV, PPV and JEV might have a minor impact on reproductive disease.

• Korean Journal of Clinical Laboratory Science
• /
• v.54 no.3
• /
• pp.173-178
• /
• 2022

The majority of the children experience milder coronavirus disease 2019 (COVID-19) symptoms. Children represent a significant source of community transmission. Children under 18 years of age account for an estimated 4.8% of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections globally. However, no conclusive statements pertaining to the multi-fold aspects of the virus in children could be drawn due to the lower prevalence of pediatric cases. The present study was conducted to identify the indirect impact of SARS-CoV-2 infections on developing herd immunity among children in the age group 3 to 18 years by investigating their antibody levels. In the study, 240 children aged 3~18 years were recruited by the Department of Pediatrics, Government Medical College and Hospital, Amritsar, India, and quantification of the antibodies was performed at the Viral Research and Diagnostic Laboratory (VRDL), Government Medical College (GMC), Amritsar, India. Out of the 240 serum samples, 197 (82.08%) showed seropositivity, while 43 (17.92%) were seronegative. When stratified, it was observed that in the age group 3~6 years, 22.33% of children were found to have anti-SARS-CoV-2 antibodies while in the age groups 7~10 years, 11~14 years, and 15~18 years, respectively, 37.06%, 30.46%, and 10.15% were seropositive. Although there was seroconversion among children which was useful for predicting the next wave, no differences in seropositivity were observed between adults and children.

• IMMUNE NETWORK
• /
• v.23 no.4
• /
• pp.31.1-31.18
• /
• 2023

Evidence suggests that the human respiratory tract, as with the gastrointestinal tract, has evolved to its current state in association with commensal microbes. However, little is known about how the airway microbiome affects the development of airway immune system. Here, we uncover a previously unidentified mode of interaction between host airway immunity and a unique strain (AIT01) of Staphylococcus epidermidis, a predominant species of the nasal microbiome. Intranasal administration of AIT01 increased the population of neutrophils and monocytes in mouse lungs. The recruitment of these immune cells resulted in the protection of the murine host against infection by Pseudomonas aeruginosa, a pathogenic bacterium. Interestingly, an AIT01-secreted protein identified as GAPDH, a well-known bacterial moonlighting protein, mediated this protective effect. Intranasal delivery of the purified GAPDH conferred significant resistance against other Gram-negative pathogens (Klebsiella pneumoniae and Acinetobacter baumannii) and influenza A virus. Our findings demonstrate the potential of a native nasal microbe and its secretory protein to enhance innate immune defense against airway infections. These results offer a promising preventive measure, particularly relevant in the context of global pandemics.

• Pediatric Infection and Vaccine
• /
• v.9 no.1
• /
• pp.79-84
• /
• 2002

Purpose : About 41% of obtained group A streptococci in the 1998 was reported as erythromycin-resistant streptococci in Seoul, Korea. The most common T serotype was T12, followed by T4 and T28. We'd like to monitor the serological changes and antibiotic sensitivity test of Streptococcus pyogenes obtained from the patients with pharyngotonsillitis and invasive diseases from 1999 through 2001. Also, it could be proposed to choose the proper antibiotic selection in the area where the rate of erythromycin-resistant streptococci is high. Methods : From Jan. 1999 to Oct. 2001, 208 isolates of group A streptococci were collected from inpatients and outpatients with pharyngotonsillitis, scarlet fever, and invasive infections in Seoul and Southern part of peninsula. All isolates were serotyped by T-agglutination, minimum inhibitory concentrations(MICs) which were determined by agar dilution methods, according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS). Results : The most common T serotype was T12(29.8%), followed by T1(23.1%), T4 (14.9%). T1 was prominent serotype compared with previous year. T serotyping, among 25 isolates obtained from the patients with scarlet fever in Southern part of peninsula mostly, was T12, T1, and T4 in order of frequency. All the isolates tested were susceptible to penicillin, cefprozil, vancomycin, ceftriaxone, and chloramphenicol. However, 23 isolates(14.2%) was resistant to erythromycin and 18 isolates(11.1%) was resistant to clarithromycin. Serotype T12 was found to be the most resistant serotype to erythromycin and/or clarithromycin. Conclusion : High rate of erythromycin-resistant streptococci which surveyed in 1998 were reduced to 14.2% in this study. We should have to further evaluate the reason of decreased resistant strains and consider the resistant strains of streptococci in choosing the antibiotics. There was no serological characteristics according to the types of disease entities. Between the serologic distributions in Seoul and the Southern part of peninsula area are same, we could presume that the serological typing of strains obtained over the country may be not different.

• Korean Journal of Microbiology
• /
• v.43 no.3
• /
• pp.173-178
• /
• 2007

The occurrence of acute respiratory infections caused by the influenza virus are particularly high during the winter season in Busan, Korea. In 2004 and 2005, a study of the rate of occurrences of the influenza virus was conducted. The results reveal that in 2004, of the 1,869 people with an acute respiratory infection that 154 (8.2%) people were infected by the influenza virus. In 2005, of the 1,579 people infected with an acute respiratory infection that 19 people (1.2%) were infected with the influenza virus. The study shows a decrease in the numbers of an influenza virus infection from 2004 to 2005. Data was collected by inspecting throat swabs and nasal discharge from those with an acute respiratory infection. Further inspection of the throat swab and nasal discharge from the infected individuals during 2004 and 2005 study show the occurrence of the different types of influenza virus in the population: 6 cases (3.5%) of influenza type A/H1N1, 129 cases (74.5%) of A/H3N2, and 38 cases (22.0%) of type B. The study conducted in 2004 and 2005 reveal that children between the ages of two and five were more likely to be infected than any other age group. In the study, about 62.2% of the infected individuals were between two and five years old. The detection rates between males and females are similar. However, it is notable that females are slightly more likely to develop an acute respiratory infection caused by the influence virus compared to their male counterparts.

• Tuberculosis and Respiratory Diseases
• /
• v.64 no.1
• /
• pp.22-27
• /
• 2008

Background: Staphylococcus aureus frequently colonizes and infects hospitalized patients. Respiratory infections with Staphylococcus aureus are common in patients with compromised airway defenses. However the mechanisms of S. aureus invasion from colonization to the epithelium are unclear. Cell invasion by S. aureus would require destruction of the extracellular matrix, which is believed to be the result of increased matrix metalloproteinases (MMP) activity. Methods: In this study, respiratory epithelial cells were infected with S. aureus. After removing the extracellular bacteria by washing, the internalized bacteria in the cells were assessed by counting the colonized forming units (CFUs). The cell adhesion proteins, dysadherin and E-cadherin, were evaluated by Western blotting. The MMPs in the bacterial invasion were evaluated by pretreating the cells with GM6001, a MMP inhibitor. Results: The internalization of S. aureus was found to be both time and dose dependent, and the increase in MMP 2 and 9 activity was also dependent on the incubation time and the initial amount of bacterial inoculation. The invasion of S. aureus was attenuated by GM6001 after 12 hours incubation with a multiply of infection (MOI)=50. The expression of dysadherin, a membrane protein, was increased in a time and dose dependent manner, while the expression of E-cadherin was decreased. Conclusion: MMPs may mediate the invasion of S. aureus into epithelial cells.

• The Journal of Korean Society of Virology
• /
• v.26 no.1
• /
• pp.9-22
• /
• 1996

Respiratory Syncytial virus (RSV) is an important cause of acute lower respiratory tract infections in human, with infants and young children being particularly susceptible. In the temperate zones, sharp annual outbreaks of RSV occur during the colder months, in both the northern and the southern hemisphere. RSV is unusual in that it can repeatedly reinfect individuals throughout life and infect babies in the presence of maternal antibody. RSV isolates can be divided into two subgroups, A and B, on the basis of their reactions with monoclonal antibodies, and the two subgroups are also distinct at the nucleotide sequence level. The specific diagnosis of RSV infection was best made by isolation of virus in tissue culture, identification of viral antigen, or by specific serologic procedures. Recently, rapid detection of RSV and analysis of RSV strain variation became possible by development of methods of reverse transcription and polymerase chain reaction amplification. In this study, to determine the genetic diversity of RSV found in Korea, 173 bp and 164 bp spanning selected regions of the RSV F and SH genes were enzymatically amplified and sequenced, respectively. Eight for F gene and three for SH gene were detected in 66 nasopharyngeal swap samples tested. Two major antigenic subgroups, A and B were confirmed from Korean samples (seven for subgroup A and one for subgroup B). At the nucleotide level of the F gene region, Korean subgroup A strains showed 95-99% homologies compared to the prototype A2 strain of subgroup A and 93-100% homologies among Korean subgroup A themselves. For the SH gene region, Korean subgroup A strain showed 97.5% homology compared to the prototype A2 strain of subgroup A, and Korean subgroup B strain showed 97% homology compared to the prototype 18537 strain of subgroup B. Most of base changes were transition and occured in codon position 3, which resulted in amino acid conservation. Using the maximum parsimony method, phylogenetic analysis indicated that Korean RSV strains formed a group with other RSV strains isolated from the United States, Canada, the Great Britain and Australia.

• Journal of Digital Convergence
• /
• v.19 no.3
• /
• pp.253-261
• /
• 2021

This study was conducted to investigate the factors influencing in the infection control performance of coronavirus infection disease-19 in registered nurse. Data were collected using descriptive structured questionnaires to examine the factors of influencing in the infection control performance. General characteristics, knowledge of infection control, anxiety, fatigue, and coronavirus infection-19 (COVID-19) respiratory infection management performance were identified from structured questionnaire. Data were analyzed using independent t-test, ANOVA, correlation analysis, and multiple regression analysis were performed using the IBM SPSS 21.0 program. Anxiety and respiratory infection management performance was a negative correlation. Multiple regression analysis indicated anxiety was predicted component of performance of coronavirus infection-19 respiratory infection management. The results indicate a need to decrease degree of anxiety by developing educational programs to improve nurses' ability to manage coronavirus infection-19 respiratory infections. In addition, it is necessary to consider applying a role-play or simulation education method so that registered nurse can take care of patients with emerging infectious diseases in advance.

• Pediatric Infection and Vaccine
• /
• v.29 no.2
• /
• pp.70-76
• /
• 2022

Coronavirus disease 2019 (COVID-19) in patients with underlying diseases, is associated with high infection and mortality rates, which may result in acute respiratory distress syndrome and death. Mucopolysaccharidosis (MPS) type II is a progressive metabolic disorder that stems from cellular accumulation of the glycosaminoglycans, heparan, and dermatan sulfate. Upper and lower airway obstruction and restrictive pulmonary diseases are common complaints of patients with MPS, and respiratory infections of bacterial or viral origin could result in fatal outcomes. We report a case of COVID-19 in a 16-year-old adolescent with MPS type II, who had been treated with idursulfase since 5 years of age. Prior to infection, the patient's clinical history included developmental delays, abdominal distension, snoring, and facial dysmorphism. His primary complaints at the time of admission included rhinorrhea, cough, and sputum without fever or increased oxygen demand. His heart rate, respiratory rate, and oxygen saturation were within the normal biological reference intervals, and chest radiography revealed no signs of pneumonia. Consequently, supportive therapy and quarantine were recommended. The patient experienced an uneventful course of COVID-19 despite underlying MPS type II, which may be the result of an unfavorable host cell environment and changes in expression patterns of proteins involved in interactions with viral proteins. Moreover, elevated serum heparan sulfate in patients with MPS may compete with cell surface heparan sulfate, which is essential for successful interaction between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and the host cell surface, thereby protecting against intracellular penetration by SARS-CoV-2.