Genetic diversity and pathogenic potential of low pathogenic H7 avian influenza viruses isolated from wild migratory birds in Korea

Kim, Y.I.,Kim, S.W.,Si, Y.J.,Kwon, H.I.,Park, S.J.,Kim, E.H.,Kim, S.m.,Lee, I.W.,Song, M.S.,Choi, Y.K. Elsevier Science 2016 Infection, genetics and evolution Vol.45 No.-

To detect the circulation of H7 avian influenza viruses, we characterized H7 viruses found in migratory birds and live poultry markets of South Korea from 2005 to 2014. Phylogenic analysis revealed that while all viruses clustered into the Eurasian-lineage of H7 avian viruses, at least 12 distinct genotypes were represented. Most H7 viruses contained at least one gene segment from the highly-pathogenic A/Sck/Hong Kong/YU100/02(H5N1)-like avian virus, and they could be separated into at least two antigenic groups. Although we did not detect genetically identical strains, HI assay demonstrated close cross-reactivity of some isolates with the H7N9 viruses from China. Animal studies revealed that most of the genotypes could replicate in the lungs of mice and chickens without prior adaptation and some, particularly H7N4 and H7N7 subtypes, induced mortality in mice. These results reinforce growing pandemic concerns regarding recent H7 viruses and emphasize the importance of continued surveillance of avian influenza viruses in the wild.

Interpretation of cryogenic-temperature Charpy fracture initiation and propagation energies by microstructural evolution occurring during dynamic compressive test of austenitic Fe-(0.4,1.0)C-18Mn steels

Kim, H.,Park, J.,Jung, J.E.,Sohn, S.S.,Lee, S. Elsevier Sequoia 2015 Materials science & engineering. properties, micro Vol.641 No.-

In the present study, Charpy impact energy (E<SUB>T</SUB>) composed of fracture initiation energy (E<SUB>I</SUB>) and propagation energy (E<SUB>P</SUB>) of austenitic Fe-(0.4,1.0)C-18Mn steels was evaluated in the temperature range from room to cryogenic temperatures by an instrumented Charpy impact tester, and was interpreted by microstructural evolution of dynamically compressed specimens. In the 1.0C-18Mn steel, the E<SUB>I</SUB> and E<SUB>P</SUB> decreased slightly with decreasing temperature, but the E<SUB>P</SUB>/E<SUB>T</SUB> ratio was kept to be about 0.5. In the 0.4C-18Mn steel, the E<SUB>I</SUB> remained almost constant or slightly decreased with decreasing temperature, while the E<SUB>P</SUB>/E<SUB>T</SUB> ratio steadily decreased, thereby leading to the lower (about 30%) cryogenic-temperature E<SUB>T</SUB> than that of the 1.0C-18Mn steel. Under the dynamic compressive loading, a considerable number of ε-martensites were formed in the 0.4C-18Mn steel, whereas they were not found in the 1.0C-18Mn steel, and their volume fractions increased steadily with decreasing temperature. This γ→ε-martensite transformation was attributed to the decrease in stacking fault energy, and resulted in the very low E<SUB>P</SUB> and resultant E<SUB>T</SUB>.

Genetic and phylogenetic characterizations of a novel genotype of highly pathogenic avian influenza (HPAI) H5N8 viruses in 2016/2017 in South Korea

Kim, Y.I.,Park, S.J.,Kwon, H.I.,Kim, E.H.,Si, Y.J.,Jeong, J.H.,Lee, I.W.,Nguyen, H.D.,Kwon, J.J.,Choi, W.S.,Song, M.S.,Kim, C.J.,Choi, Y.K. Elsevier Science 2017 INFECTION GENETICS AND EVOLUTION Vol.53 No.-

<P>During the outbreaks of highly pathogenic avian influenza (HPAI) H5N6 viruses in 2016 in South Korea, novel H5N8 viruses were also isolated from migratory birds. Phylogenetic analysis revealed that the HA gene of these H5N8 viruses belonged to clade 2.3.4.4, similarly to recent H5Nx viruses, and originated from A/Brk/Korea/Gochang1/14(H5N8), a minor lineage of H5N8 that appeared in 2014 and then disappeared. At least four reassortment events occurred with different subtypes (H5N8, H7N7, H3N8 and H10N7) and a chicken challenge study revealed that they were classified as HPAI viruses according to OIE criteria. (C) 2017 Elsevier B.V. All rights reserved.</P>

Neural stem cells injured by oxidative stress can be rejuvenated by GV1001, a novel peptide, through scavenging free radicals and enhancing survival signals

Park, H.H.,Yu, H.J.,Kim, S.,Kim, G.,Choi, N.Y.,Lee, E.H.,Lee, Y.J.,Yoon, M.Y.,Lee, K.Y.,Koh, S.H. Elsevier BV 2016 NeuroToxicology Vol.55 No.-

<P>Oxidative stress is a well-known pathogenic mechanism of a diverse array of neurological diseases, and thus, numerous studies have attempted to identify antioxidants that prevent neuronal cell death. GV1001 is a 16-amino-acid peptide derived from human telomerase reverse transcriptase (hTERT). Considering that hTERT has a strong antioxidant effect, whether GV1001 also has an antioxidant effect is a question of interest. In the present study, we aimed to investigate the effects of GV1001 against oxidative stress in neural stem cells (NSCs). Primary culture NSCs were treated with different concentrations of GV1001 and/or hydrogen peroxide (H2O2) for various time durations. The H2O2 decreased the viability of the NSCs in a concentration-dependent manner, with 200 mu M H2O2 significantly decreasing both proliferation and migration. However, treatment with GV1001 rescued the viability, proliferation and migration of H2O2 injured NSCs. Consistently, free radical levels were increased in rat NSCs treated with H2O2, while co-treatment with GV1001 significantly reduced these levels, especially the intracellular levels. In addition, GV1001 restored the expression of survival-related proteins and reduced the expression of death associated ones in NSCs treated with H2O2. In conclusion, GV1001 has antioxidant and neuroprotective effects in NSCs following treatment with H2O2, which appear to be mediated by scavenging free radicals, increasing survival signals and decreasing death signals. (C) 2016 Elsevier B.V. All rights reserved.</P>

Cross-protective efficacies of highly-pathogenic avian influenza H5N1 vaccines against a recent H5N8 virus

Park, S.J.,Si, Y.J.,Kim, J.,Song, M.S.,Kim, S.m.,Kim, E.H.,Kwon, H.i.,Kim, Y.I.,Lee, O.J.,Shin, O.S.,Kim, C.J.,Shin, E.C.,Choi, Y.K. Academic Press 2016 Virology Vol.498 No.-

<P>To investigate cross-protective vaccine efficacy of highly-pathogenic avian influenza H5N1 viruses against a recent HPAI H5N8 virus, we immunized C57BL/6 mice and ferrets with three alum-adjuvanted inactivated whole H5N1 vaccines developed through reverse-genetics (Rg): [Vietnam/1194/04xPR8 (clade 1), Korea/W149/06xPR8 (clade 2.2), and Korea/ES223N/03xPR8 (clade 2.5)]. Although relatively low cross-reactivities (10-40 HI titer) were observed against heterologous H5N8 virus, immunized animals were 100% protected from challenge with the 20 mLD(50) of H5N8 virus, with the exception of mice vaccinated with 3.5 mu g of Rg Vietnam/1194/04xPR8. Of note, the Rg Korea/ES223N/03xPR8 vaccine provided not only effective protection, but also markedly inhibited viral replication in the lungs and nasal swabs of vaccine recipients within five days of HPAI H5N8 virus challenge. Further, we demonstrated that antibody-dependent cell-mediated cytotoxicity (ADCC) of an antibody-coated target cell by cytotoxic effector cells also plays a role in the heterologous protection of H5N1 vaccines against H5N8 challenge. (C) 2016 Elsevier Inc. All rights reserved.</P>

Surveillance of avian influenza virus in wild bird fecal samples from South Korea, 2003-2008.

Kang, H M,Jeong, O M,Kim, M C,Kwon, J S,Paek, M R,Choi, J G,Lee, E K,Kim, Y J,Kwon, J H,Lee, Y J [Wildlife Disease Association] 2010 JOURNAL OF WILDLIFE DISEASES Vol.46 No.3

<P>We analyzed the results from nationwide surveillance of avian influenza (AI) from birds in South Korea's major wild bird habitats and the demilitarized zone of South Korea, 2003-2008. Of 28,214 fecal samples analyzed, 225 yielded influenza viruses, for a prevalence of 0.8%. Hemagglutinin (HA) subtypes H1-H12 and all nine neuraminidase (NA) subtypes were detected. The dominant HA subtypes were H6, H1, and H4, and the most common NA subtypes were N2, N1, and N6. Among the 38 HA/NA subtype combinations, the most common were H4N6, H6N1, and H5N2. Thirty-seven low-pathogenic AI (LPAI) viruses of the H5 and H7 subtype were detected. Among them, we identified bird species for 16 H5- and H7-positive fecal samples using a DNA bar-coding system instituted in 2007; all birds were identified as Anseriformes. The HA gene of the H5 wild bird isolates belonged to the Eurasian avian lineage, and could be clearly distinguished from the sublineage H5N1 highly pathogenic AI (HPAI) of the Eurasian and American avian lineages. Whereas H7 LPAI viruses did not group as a separate sublineage with H7 HPAI viruses, H7 isolates were closely related with the Eurasian avian lineage.</P>

자외선의 조사간격이 브로일러 병아리의 볏 피부중 비타민 D₃함량에 미치는 영향

조인호,장윤환,이은택,여영수,배은경,김중달 한국축산학회 1994 한국축산학회지 Vol.36 No.1

This study was conducted to determine the content, of previtamin D₃(PreD₃), lumisterol₃(L₃), vitamin D₃(VD₃) and provitamin D₃(ProD₃) in comb skski of broiler chicks exposed to medium ware ultraviolet(UVB) lights in different interval. The broiler Hubbard line day old chicks(199 = 10 control + 3 irradiation interval × 9 elapsed time × 7 replica) were fed vitamin D deficient diet for 3 weeks in a windowless subdued light room and exposed to 297 ㎚ UVB light by 0.068 mJ/㎝-(10 min) three times in 0, 12 or 24 h interval. The comb skin were taken at 0, 6, 12, 18, 24, 48, 96, 144 or 240 h after last irradiation, and epidermis and dermis were separated. The lipid in sample was extracted by 9% ethyl acetate/hexane and purified by Sep-Pak silica catridge. The stright phase HPI-C was applied to analyze the concentration of Prop; and its photoproducts. When chicks were exposed once to UVB light for 30 min without interval, the mole % of ProD₃ in comb epidermis were 100% at control and 52.65% at 0 h after irradiation, thereafter it increased gradually to 88.17% at 240 h. PreD₃ and L₃ presented the maximum mole % at 0 h. VD₃ showed the peak value at 12 h. then decreased slowly. As UVB light was utilized to irradiate the chicks for 10 thin three times in 12 h interval, the ProD₃ mole portion in epidermis at 0 h was 76.4%, the lowest value among tested. PreD₃ and 1-3 preserved the highest level at 24 and 0 h, respectively, thereafter decreased gradully. VD₃ showed a peak at 6 h after exposure. When 24 h interval system was treated, the lowest value of ProD₃ 83.52% was appeared at 0 h. PreD₃ and L3 showed the highest level at 6 and 0 h, respectively. Mole ale of VD₃ had a peak value at 6 h and thin decreased. The mole % of ProD₃ and its photoproduets in comb dermis presented similar trends of time course variation as in those in epidermis. In respecting the method of UVB irradiation the PreD₃, L, and VDT were produced more quickly and largely in no intend system as compared to the time and amount produced in 12 or 24 h interval system.

Evaluation of the zoonotic potential of a novel reassortant H1N2 swine influenza virus with gene constellation derived from multiple viral sources

Lee, J.H.,Pascua, P.N.Q.,Decano, A.G.,Kim, S.M.,Park, S.J.,Kwon, H.I.,Kim, E.H.,Kim, Y.I.,Kim, H.,Kim, S.Y.,Song, M.S.,Jang, H.K.,Park, B.K.,Choi, Y.K. Elsevier Science 2015 INFECTION GENETICS AND EVOLUTION Vol.34 No.-

In 2011-2012, contemporary North American-like H3N2 swine influenza viruses (SIVs) possessing the 2009 pandemic H1N1 matrix gene (H3N2pM-like virus) were detected in domestic pigs of South Korea where H1N2 SIV strains are endemic. More recently, we isolated novel reassortant H1N2 SIVs bearing the Eurasian avian-like swine H1-like hemagglutinin and Korean swine H1N2-like neuraminidase in the internal gene backbone of the H3N2pM-like virus. In the present study, we clearly provide evidence on the genetic origins of the novel H1N2 SIVs virus through genetic and phylogenetic analyses. In vitro studies demonstrated that, in comparison with a pre-existing 2012 Korean H1N2 SIV [A/swine/Korea/CY03-1½012 (CY03-1½012)], the 2013 novel reassortant H1N2 isolate [A/swine/Korea/CY0423/2013 (CY0423-12/2013)] replicated more efficiently in differentiated primary human bronchial epithelial cells. The CY0423-12/2013 virus induced higher viral titers than the CY03-1½012 virus in the lungs and nasal turbinates of infected mice and nasal wash samples of ferrets. Moreover, the 2013 H1N2 reassortant, but not the intact 2012 H1N2 virus, was transmissible to naive contact ferrets via respiratory-droplets. Noting that the viral precursors have the ability to infect humans, our findings highlight the potential threat of a novel reassortant H1N2 SIV to public health and underscore the need to further strengthen influenza surveillance strategies worldwide, including swine populations.

Transmissibility of novel H7N9 and H9N2 avian influenza viruses between chickens and ferrets

Ku, K.B.,Park, E.H.,Yum, J.,Kim, H.M.,Kang, Y.M.,Kim, J.C.,Kim, J.A.,Kim, H.S.,Seo, S.H. 3M Company 2014 Virology Vol.450 No.-

Previous studies have shown that the H7N9 avian influenza virus cannot be transmitted efficiently between ferrets via respiratory droplets. Here, we studied the infectivity of the H7N9 avian influenza virus in chickens and its transmissibility from infected to naive chickens and ferrets. The H7N9 virus (A/Anhui/½013) replicated poorly in chickens and could not be transmitted efficiently from infected chickens to naive chickens and ferrets. H7N9 virus was shed from chicken tracheae for only 2 days after infection and from chicken cloacae for only 1 day after infection, while the H9N2 avian influenza virus, which is endemic in chickens in many Asian countries, was shed from tracheae and cloacae for 8 days after infection. Taken together, our results suggest that chickens may be a poor agent of transmission for the H7N9 virus to other chickens and to mammals, including humans.

Supplementation of oil-based inactivated H9N2 vaccine with M2e antigen enhances resistance against heterologous H9N2 avian influenza virus infection

Park, J.K.,Lee, D.H.,Cho, C.H.,Yuk, S.S.,To, E.O.,Kwon, J.H.,Noh, J.Y.,Kim, B.Y.,Choi, S.W.,Shim, B.S.,Song, M.K.,Lee, J.B.,Park, S.Y.,Choi, I.S.,Song, C.S. Elsevier Scientific Pub. Co 2014 Veterinary microbiology Vol.169 No.3

Avian influenza virus (AIV) subtype H9N2 has been evolving rapidly and vaccine escape variants have been reported to cause circulation of infections and economic losses. In the present study, we developed and evaluated ectodomain of the AIV matrix 2 (M2e) protein as a supplementing antigen for oil-based inactivated H9N2 vaccine to increase resistance against vaccine escape variants. AIV H9N2 M2e antigen was expressed in Escherichia coli and supplemented to inactivated H9N2 oil emulsion vaccine. Specific pathogen-free chickens received a single injection of inactivated H9N2 oil emulsion vaccines with or without M2e supplementation. At three weeks post vaccination, hemagglutination inhibition tests and enzyme-linked immunosorbent assays were performed to determine serological immune responses. Challenge study using a vaccine escape H9N2 variant was performed to evaluate the efficacy of M2e supplementation. M2e antigen supplemented in oil emulsion vaccine was highly immunogenic, and a single M2e-supplemented vaccination reduced challenge virus replication and shedding more effectively than non-supplemented vaccination.