Experimental infection of mandarin duck with highly pathogenic avian influenza A (H5N8 and H5N1) viruses

Kang, H.M.,Lee, E.K.,Song, B.M.,Heo, G.B.,Jung, J.,Jang, I.,Bae, Y.C.,Jung, S.C.,Lee, Y.J. Elsevier Scientific Pub. Co 2017 Veterinary microbiology Vol.198 No.-

<P>A highly pathogenic avian influenza (HPAI) H5N8 virus was first detected in poultry and wild birds in South Korea in January 2014. Here, we determined the pathogenicity and transmissibility of three different clades of 1-15 viruses in mandarin ducks to examine the potential for wild bird infection. H5N8 (Glade 2.3.4.4) replicated more efficiently in the upper and lower respiratory tract of mandarin ducks than two previously identified H5N1 virus clades (clades 2.2 and 2.3.2.1). However, none of the mandarin ducks infected with H5N8 and H5N1 viruses showed severe clinical signs or mortality, and gross lesions were only observed in a few tissues. Viral replication and shedding were greater in H5N8-infected ducks than in H5N1-infected ducks. Recovery of all viruses from control duck in contact with infected ducks indicated that the highly pathogenic H5 viruses spread horizontally through contact. Taken together, these results suggest that H5N8 viruses spread efficiently in mandarin ducks. Further studies of pathogenicity in wild birds are required to examine possible long-distance dissemination via migration routes. (C) 2016 Elsevier B.V. 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>

Accelerated cosmological expansion without tension in the Hubble parameter : Fast evolution of the Hubble parameter <i>H(z)</i>

van Putten, Maurice H.P.M.,Gwak, B.,Kang, G.,Kim, C.,Kim, H.-C.,Lee, C.-H.,Lee, J.,Lee, S.,Lee, W. EDP Sciences 2018 The European Physical Journal Conferences Vol.168 No.-

<P>The <I>H</I>0-tension problem poses a confrontation of dark energy driving latetime cosmological expansion measured by the Hubble parameter<I> H</I>(<I>z</I>) over an extended range of redshifts <I>z</I>. Distinct values <I>H</I>0 ≃ 73 km s<SUP>-1</SUP> Mpcs<SUP>-1</SUP> and <I>H</I>0 ≃ 68 km s<SUP>-1</SUP> Mpcs<SUP>-1</SUP> obtain from surveys of the Local Universe and, respectively, ΛCBM analysis of the CMB. These are representative of accelerated expansion with <I>H</I>′(0) ≃ 0 by [see formula in PDF] and, respectively, <I>H</I>′(0) > 0 in ΛCDM, where [see formula in PDF] is a fundamental frequency of the cosmological horizon in a Friedmann-Robertson-Walker universe with deceleration parameter <I>q</I>(<I>z</I>) = -1 + (1+z)<I>H</I><SUP>-1</SUP><I>H</I>′(z). Explicit solution <I>H</I>(z) = <I>H</I>0 [see formula in PDF] and, respectively, <I>H</I>(z) = <I>H</I>0[see formula in PDF] are here compared with recent data on <I>H</I>(<I>z</I>) over 0 ≲ z ≲ 2.The first is found to be free of tension with H0 from local surveys, while the latter is disfavored at 2:7σ A further confrontation obtains in galaxy dynamics by a finite sensitivity of inertia to background cosmology in weak gravity, putting an upper bound of <I>m</I> ≲ 10<SUP>-30</SUP> eV on the mass of dark matter. A <I>C</I><SUP>0</SUP> onset to weak gravity at the de Sitter scale of acceleration <I>adS</I> = <I>cH</I>(<I>z</I>), where <I>c</I> denotes the velocity of light, can be seen in galaxy rotation curves covering 0 ≲ <I>z</I> ≲ 2 Weak gravity in galaxy dynamics hereby provides a proxy for cosmological evolution.</P>

국내 HIV 감염자에서의 기회성 감염증에 관한 연구(Ⅱ)

신영오,이주실,이홍래,강춘,남정구,최병선,김상형,민복순,이재상 국립보건연구원 1994 국립보건원보 Vol.31 No.1

Novel dentin phosphoprotein frameshift mutations in dentinogenesis imperfecta type II

Lee, K‐,E,Kang, H‐,Y,Lee, S‐,K,Yoo, S‐,H,Lee, J‐,C,Hwang, Y‐,H,Nam, KH,Kim, J‐,S,Park, J‐,C,Kim, J‐,W Blackwell Publishing Ltd 2011 Clinical genetics Vol.79 No.4

<P>Lee K‐E, Kang H‐Y, Lee S‐K, Yoo S‐H, Lee J‐C, Hwang Y‐H, Nam KH, Kim J‐S, Park J‐C, Kim J‐W. Novel dentin phosphoprotein frameshift mutations in dentinogenesis imperfecta type II.</P><P>The dentin sialophosphoprotein (<I>DSPP</I>) gene encodes the most abundant non‐collagenous protein in tooth dentin and DSPP protein is cleaved into several segments including the highly phosphorylated dentin phosphoprotein (DPP). Mutations in the <I>DSPP</I> gene have been solely related to non‐syndromic form of hereditary dentin defects. We recruited three Korean families with dentinogenesis imperfecta (DGI) type II and sequenced the exons and exon–intron boundaries of the <I>DSPP</I> gene based on the candidate gene approach. Direct sequencing of PCR products and allele‐specific cloning of the highly repetitive exon 5 revealed novel single base pair (bp) deletional mutations (c.2688delT and c.3560delG) introducing hydrophobic amino acids in the hydrophilic repeat domain of the DPP coding region. All affected members of the three families showed exceptionally rapid pulp chambers obliteration, even before tooth eruption. Individuals with the c.3560delG mutation showed only mild, yellowish tooth discoloration, in contrast to the affected individuals from two families with c.2688delT mutation. We believe that these results will help us to understand the molecular pathogenesis of DGI type II as well as the normal process of dentin biomineralization.</P>

Transcriptomic profiling and its implications for the H2 production of a non-methanogen deficient in the frhAGB-encoding hydrogenase

Lee, S. H.,Kim, M. S.,Kim, Y. J.,Kim, T. W.,Kang, S. G.,Lee, H. S. Springer Science + Business Media 2017 Applied microbiology and biotechnology Vol.101 No.12

<P>The F-420-reducing hydrogenase of methanogens functions in methanogenesis by providing reduced coenzyme F-420 (F420H2) as an electron donor. In non-methanogens, however, their physiological function has not been identified yet. In this study, we constructed an Delta frhA mutant, whose frhA gene encoding the hydrogenase alpha subunit was deleted, in the non-methanogenic Thermococcus onnurineus NA1 as a model organism. There was no significant difference in the formate-dependent growth between the mutant and the wild-type strains. Interestingly, the mutation in the frhA gene affected the expression of genes involved in various cellular functions such as H-2 oxidation, chemotactic signal transduction, and carbon monoxide (CO) metabolism. Among these genes, the CO oxidation gene cluster, enabling CO-dependent growth and H-2 production, showed a 2.8- to 7.0-fold upregulation by microarray-based whole transcriptome expression profiling. The levels of proteins produced by this gene cluster were also significantly increased not only under the formate condition but also under the CO condition. In a controlled bioreactor, where 100% CO was continuously fed, the Delta frhA mutant exhibited significant increases in cell growth (2.8-fold) and H-2 production (3.4-fold). These findings strongly imply that this hydrogenase is functional in non-methanogens and is related to various cellular metabolic processes through an unidentified mechanism. An understanding of the mechanism by which the frhA gene deletion affected the expression of other genes will provide insights that can be applied to the development of strategies for the enhancement of H-2 production using CO as a substrate.</P>

Multiple novel H5N6 highly pathogenic avian influenza viruses, South Korea, 2016

Lee, E.K.,Song, B.M.,Lee, Y.N.,Heo, G.B.,Bae, Y.C.,Joh, S.J.,Park, S.C.,Choi, K.S.,Lee, H.J.,Jang, I.,Kang, M.S.,Jeong, O.M.,Choi, B.K.,Lee, S.M.,Jeong, S.C.,Park, B.K.,Lee, H.S.,Lee, Y.J. Elsevier Science 2017 INFECTION GENETICS AND EVOLUTION Vol.51 No.-

<P>We report the identification of novel highly pathogenic avian influenza viruses of subtype H5N6, Glade 23.4.4, that presumably originated from China. In addition, reassortant strains with Eurasian lineage low pathogenic avian influenza viruses were isolated in wild birds and poultry in South Korea. The emergence of these novel H5N6 viruses and their circulation among bird populations are of great concern because of the potential for virus dissemination with intercontinental wild bird migration. (C) 2017 Elsevier B.V. All rights reserved.</P>

Gibberellin secreting rhizobacterium, Pseudomonas putida H-2-3 modulates the hormonal and stress physiology of soybean to improve the plant growth under saline and drought conditions

Kang, S.M.,Radhakrishnan, R.,Khan, A.L.,Kim, M.J.,Park, J.M.,Kim, B.R.,Shin, D.H.,Lee, I.J. Gauthier-Villars ; Elsevier Science Ltd 2014 Vol. No.

The physiological changes in tolerant soybean plants under salt and drought stress conditions with Pseudomonas putida H-2-3 were investigated. A bacterial isolate H-2-3 was isolated from soil and identified as Pseudomonas putida H-2-3 by 16S rDNA sequences. The treatment of P. putida H-2-3 significantly increased the length, fresh and dry weight of shoot and chlorophyll content in gibberellins (GAs) deficient mutant Waito-c rice seedlings over the control, it might be the presence of GA<SUB>1</SUB>, GA<SUB>4,</SUB> GA<SUB>9</SUB> and GA<SUB>20.</SUB> The soybean plant growth was retarded in salt (120 mM sodium chloride) and drought (15% polyethylene glycol) stress conditions at 10 days treatments, while P. putida H-2-3 effectively enhanced the shoot length and fresh weight of plants suffered at salt and drought stress. The chlorophyll content was lower in abiotic stress conditions and bacterial inoculant P. putida H-2-3 mitigated the stress effects by an evidence of higher quantity of chlorophyll content in plants exposed to salt and drought. The stress hormonal analysis revealed that individual treatment of P. putida H-2-3, salt and drought significantly enhanced the abscisic acid and salicylic acid content than their control. P. putida H-2-3 applied to salt and drought stressed plants showed a lower level of abscisic acid and salicylic acid and a higher level of jasmonic acid content. Under stress condition induced by salt and drought in plants expressed higher level of total polyphenol, superoxide dismutase and radical scavenging activity and no significant changes in flavonoids. The bio-inoculant, P. putida H-2-3 modulated those antioxidants by declining superoxide dismutase, flavonoids and radical scavenging activity. P. putida H-2-3 induced tolerance against abiotic stress was confirmed by a reduction of Na content in abiotic stressed plants. The results suggest that P. putida H-2-3 application reprograms the chlorophyll, stress hormones and antioxidants expression in abiotic stress affected soybean plant and improves their growth under stress environment.

Small molecule inhibition of Epstein-Barr virus nuclear antigen-1 DNA binding activity interferes with replication and persistence of the viral genome

Lee, E.K.,Kim, S.Y.,Noh, K.W.,Joo, E.H.,Zhao, B.,Kieff, E.,Kang, M.S. Elsevier/North-Holland 2014 ANTIVIRAL RESEARCH Vol.104 No.-

The replication and persistence of extra chromosomal Epstein-Barr virus (EBV) episome in latently infected cells are primarily dependent on the binding of EBV-encoded nuclear antigen 1 (EBNA1) to the cognate EBV oriP element. In continuation of the previous study, herein we characterized EBNA1 small molecule inhibitors (H20, H31) and their underlying inhibitory mechanisms. In silico docking analyses predicted that H20 fits into a pocket in the EBNA1 DNA binding domain (DBD). However, H20 did not significantly affect EBNA1 binding to its cognate sequence. A limited structure-relationship study of H20 identified a hydrophobic compound H31, as an EBNA1 inhibitor. An in vitro EBNA1 EMSA and in vivo EGFP-EBNA1 confocal microscopy analysis showed that H31 inhibited EBNA1-dependent oriP sequence-specific DNA binding activity, but not sequence-nonspecific chromosomal association. Consistent with this, H31 repressed the EBNA1-dependent transcription, replication, and persistence of an EBV oriP plasmid. Furthermore, H31 induced progressive loss of EBV episome. In addition, H31 selectively retarded the growth of EBV-infected LCL or Burkitt's lymphoma cells. These data indicate that H31 inhibition of EBNA1-dependent DNA binding decreases transcription from and persistence of EBV episome in EBV-infected cells. These new compounds might be useful probes for dissecting EBNA1 functions in vitro and in vivo.

Antagonistic effect of acetic acid and salt for inactivating <i>Escherichia coli</i> O157:H7 in cucumber puree

Lee, S.Y.,Rhee, M.S.,Dougherty, R.H.,Kang, D.H. Blackwell Publishing Ltd 2010 Journal of applied microbiology Vol.108 No.4

<P>Abstract</P><P>Aim: </P><P>This study was conducted to investigate the effects of acetic acid alone or combined with salt for inhibiting <I>Escherichia coli</I> O157:H7 in cucumber puree during storage time at 5 and 22°C.</P><P>Methods and Results: </P><P>Samples at various concentrations were prepared by the addition of acetic acid (0%, 0·25%, 0·5%, 0·75%, 1%, 2%, 2·5%, or 3%) along with NaCl (0% or 3%) and pureed cucumber (50% or 94%). The effect of storage temperature (5 and 22°C) on the survival of <I>E. coli</I> O157:H7 was also tested. The numbers of <I>E. coli</I> O157:H7 were reduced as the amount of acetic acid increased (<I>P </I><<I> </I>0·01) and rate of reduction was more rapid at 22°C than at 5°C. Combinations of acetic acid and salt were less effective at killing <I>E. coli</I> O157:H7 in simulated pickled cucumber samples stored at 5 and 22°C than did treatment of acetic acid alone. The concentration of pureed cucumber affected the reduction rate of <I>E. coli</I> O157:H7. When stored at 5°C, <I>E. coli</I> O157:H7 survived for up to 23 days in a mixture of 94% cucumber puree, 1% acetic acid, and 3% NaCl.</P><P>Conclusions: </P><P>There was the antagonistic effect of acetic acid and 3% NaCl with regard to the reduction of <I>E. coli</I> O157:H7.</P><P>Significance and Impact of the Study: </P><P>Our results suggest that pickled cucumbers prepared with at least 2% acetic acid and stored at room temperature (22°C) after 3 days storage can free from <I>E. coli</I> O157:H7 without heating.</P>