• Pediatric Infection and Vaccine
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• 제23권3호
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• pp.236-239
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• 2016

길랭-바레 증후군은 약 3분의 2에서 선행 감염이 원인이 되며 면역반응 때문에 발병하는 것으로 알려져 있는데, 그 중 인플루엔자 바이러스는 비교적 드문 원인이다. 발병 기전과 관련된 항체들에 대한 보고들은 몇 차례 있었지만 길랭-바레 증후군 환자의 뇌척수액에서 인플루엔자 바이러스가 직접 검출된 증례는 없었다. 6세 여아가 내원 1주 전 인플루엔자 A로 진단된 후 oseltamivir를 복용하며 증상이 호전되었고, 내원 2일 전 두통 및 하루 전 양하지 위약감이 생겨서 응급실로 왔다. 신체 진찰, 뇌척수액 검사, 신경전도 검사, 척수 자기공명영상 등의 결과를 토대로 길랭-바래 증후군으로 진단하였고, 뇌척수액중합효소 연쇄반응 검사에서 인플루엔자 A 바이러스가 검출되었으며, 면역글로불린 정맥 투여 후 점차 증상이 호전되었다. 본 증례를 통하여 저자들은 인플루엔자 바이러스가 뇌척수액 내로 직접 침투한 것이 길랭-바레 증후군의 발생과 연관이 있을 것이라고 판단하며, 향후 그 기전에 대한 연구가 필요하겠다.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.588-594
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• 2010

Two types of resin-conjugated Tamiflu analogs were synthesized by modifying our original synthetic route of oseltamivir phosphate (Tamiflu). The prepared resins bound to influenza virus neuraminidase, the main target of Tamiflu. The resins will be useful for isolating and identifying presumed endogenous vertebrate proteins that interact with Tamiflu, which might relate to the rarely observed abnormal behavior exhibited by some influenza patients treated with Tamiflu.

• Pediatric Infection and Vaccine
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• 제23권2호
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• pp.149-154
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• 2016

그 동안 다양한 병원체와 가와사끼병의 관련성이 제기되어 왔으나 아직 확실한 원인으로 증명된 것은 없다. 본 증례는 가와사끼병과 폐렴미코플라스마, 인플루엔자 감염이 동시에 병발한 환자를 소개한다. 27개월 남아가 발열과 기침, 콧물 등의 증상으로 내원하였다. 외래에서 인플루엔자 A 감염을 확인하고 oseltamivir를 복용하였으나 발열이 지속되고 경부 림프절 비대, 양측성 결막 충혈, 입술의 발적과 갈라짐, 딸기혀, BCG 접종 부위의 발진을 보였다. 이에 가와사끼병으로 진단하고 면역글로불린을 정맥주사 하였다. 환아는 혈청 항미코플라스마 IgM 항체가 양성이었고 비인두 도말 중합효소 연쇄반응 검사에서 폐렴미코플라스마 양성으로 나타났다. 본 증례와 더불어 가와사끼병과의 연관성이 거론되었던 병원체들을 살펴보고 가와사끼병의 병인에 대한 가설들을 고찰하여 가와사끼병의 증상이나 관상동맥 병변이 폐렴미코플라스마와 인플루엔자 뿐 아니라 다양한 감염에서 발생할 수 있을 것으로 예상하였다.

• Clinical and Experimental Pediatrics
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• 제54권3호
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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.

• Clinical and Experimental Pediatrics
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• 제52권8호
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• pp.862-868
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• 2009

Since its identification in April 2009, a swine-origin H1N1 influenza A virus (S-OIV) which is a reassortment of gene segments from both North American triple-reassortant and Eurasian swine influenza has been widely spread among humans in unexpected rapidity. To date, each gene segment of the 2009 influenza A (H1N1) outbreak viruses have shown high (99.9%) neucleotide sequence identity. As of July 6, 94,512 people have been infected in 122 countries, of whom 429 have died with an overall case-fatality rate of <0.5%. Most confirmed cases of S-OIV infection have been characterized by self-limited, uncomplicated febrile respiratory illness and 38% of cases have also included vomiting or diarrhea. Standard plus droplet precautions should be adhered to at all times. Tests on S-OIV have indicated that current new H1N1 viruses are sensitive to neuraminidase inhibitors (oseltamivir). However, current less virulent S-OIV may evolve into a pathogenic strain or acquire antiviral resistance, potentially with more severe clinical consequences. Efforts to control these outbreaks would be based on our understanding of novel S-OIV and previous influenza pandemics.

• Journal of Microbiology and Biotechnology
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• 제21권5호
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• pp.449-454
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• 2011

The infection of pandemic influenza viruses such as swine flu (H1N1) and avian flu viruses to the host cells is related to the following two factors: First, the surface protein such as HA (hemagglutinin) and NA (neuraminidase) of the influenza virus. Second, the specific structure of the oligosaccharide [sialic acid(${\alpha}2$-6) galactose(${\beta}1$-4)glucose or sialic acid(${\alpha}2$-3)galactose(${\beta}1$-4)glucose] on the host cell. After recognizing the specific structure of the oligosaccharide on the surface of host cells by the surface protein of the influenza virus, the influenza virus can secrete sialidase and cleave the sialic acid attached on the final position of the specific structure of the oligosaccharide on the surface of host cells. Tamiflu (oseltamivir), known as a remedy of swine flu, has a saccharide analog structure, especially the sialic acid analog. Tamiflu can inhibit the invasion of influenza viruses (swine flu and avian flu viruses) into the host cells by competition with sialic acid on the terminal position of the specific oligosaccharide on the surface of the host cell. Because of the emergence of Tamiflu resistance, the development of new potent anti-influenza inhibitors is needed. The inhibitors with positive-charge groups have potential as antiviral therapeutics, and the strain specificity must also be resolved.

• 통합자연과학논문집
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• 제8권3호
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• pp.209-213
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• 2015

Influenza A virus (H1N1) causes and spreads infectious diseases and becomes a major health threat in humans. Among the subtypes of influenza virus, neuraminidase (NA) plays an important role in viral life cycle and becomes an attractive therapeutic target. Currently two NA inhibitors namely Zanamivir and Oseltamivir are available for treating infectious diseases. Recently five naturally derived polyphenols extracted from Phellinus baumii was reported as inhibitors against NA. Molecular docking is powerful tool in computer aided drug designing which aids in exploring and elucidating the properties of the molecules from their 3D structure. Hence, in the present study, molecular docking was carried out on reported polyphenols isolated from ethanolic extract of fruiting bodies of Phellinus baumii. The objective of this work was to study the interaction and to propose the binding mode of these compounds within the binding site of H1N1 neuraminidase. The results showed these compounds had better binding energy and H-bond interactions with the important active site residues of the receptor which authenticate these compounds contributes to inhibitory activity of neuraminidase to treat influenza infection.

• Journal of Ginseng Research
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• 제35권1호
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• pp.104-110
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• 2011

Korean red ginseng (RG), which is a ginseng treated by heating and steaming, has biological activity similar to Panax ginseng. The effect of ginseng on influenza infection has not been studied although it is known to have a broad range of biological activities. The aim of the study is to investigate the effect of RG extract on influenza A (H1N1) virus infection. We investigated the inhibitory effect of RG extract on plaque formation by influenza A virus in a cell-based plaque assay, and the effect of orally administered RG on influenza A virus infection in mice. RG extract, which was applied at a non-cytotoxic concentration, inhibited plaque formation by influenza A virus in the cell-based plaque assay. The orally administered RG extract ameliorated body weight loss and significantly increased survival in mice infected with influenza A virus. Our results suggest that RG extract has components that reduce the severity of infection by influenza A virus and could potentially be used as a complement to treatment of influenza A virus infections.

• Osong Public Health and Research Perspectives
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• 제9권6호
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• pp.348-353
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• 2018

Objectives: This study was conducted to determine whether essential oils had anti-influenza A/WS/33 virus activity and whether there were specific compounds associated with this activity. Methods: There were 63 essential oils evaluated for anti-influenza (A/WS/33 virus) activity using a cytopathic effect reduction method. The chemical composition of the anti-influenza essential oils was phytochemically analyzed by gas chromatography-mass spectrometry. Results: The antiviral assays demonstrated that 11 of the 62 essential oils ($100{\mu}g/mL$) possessed anti-influenza activity, reducing visible cytopathic effects of influenza A/WS/33 virus activity by > 30%. Furthermore, marjoram, clary sage and anise oils exhibited anti-influenza A/WS/33 virus activity of > 52.8%. However, oseltamivir (the anti-influenza A and B drug), showed cytotoxicity at the same concentration ($100{\mu}g/mL$) as the essential oils. The chemical composition detected by GC-MS analysis, differed amongst the 3 most potent anti-viral essential oils (marjoram, clary sage and anise oils) except for linalool, which was detected in all 3 essential oils. Conclusion: This study demonstrated anti-influenza activity in 11 essential oils tested, with marjoram, clary sage and anise essential oils being the most effective at reducing visible cytopathic effects of the A/WS/33 virus. All 3 oils contained linalool, suggesting that this may have anti-influenza activity. Further investigation is needed to characterize the antiviral activity of linalool against influenza A/WS/33 virus.

• Journal of Microbiology and Biotechnology
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• 제31권9호
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• pp.1305-1310
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• 2021

Shikimate is a key high-demand metabolite for synthesizing valuable antiviral drugs, such as the anti-influenza drug, oseltamivir (Tamiflu). Microbial-based strategies for shikimate production have been developed to overcome the unstable and expensive supply of shikimate derived from traditional plant extraction processes. In this study, a microbial cell factory using Corynebacterium glutamicum was designed to overproduce shikimate in a fed-batch culture system. First, the shikimate kinase gene (aroK) responsible for converting shikimate to the next step was disrupted to facilitate the accumulation of shikimate. Several genes encoding the shikimate bypass route, such as dehydroshikimate dehydratase (QsuB), pyruvate kinase (Pyk1), and quinate/shikimate dehydrogenase (QsuD), were disrupted sequentially. An artificial operon containing several shikimate pathway genes, including aroE, aroB, aroF, and aroG were overexpressed to maximize the glucose uptake and intermediate flux. The rationally designed shikimate-overproducing C. glutamicum strain grown in an optimized medium produced approximately 37.3 g/l of shikimate in 7-L fed-batch fermentation. Overall, rational cell factory design and culture process optimization for the microbial-based production of shikimate will play a key role in complementing traditional plant-derived shikimate production processes.