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>

The evolutionary dynamics of highly pathogenic avian influenza H5N1 in south-central Vietnam reveals multiple clades evolving from Chinese and Cambodian viruses

Nguyen, T.H.,Than, V.T.,Thanh, H.D.,Nguyen, V.Q.,Nguyen, K.H.,Nguyen, D.T.,Park, J.H.,Chung, I.S.,Jeong, D.G.,Chang, K.T.,Oh, T.K.,Kim, W. Pergamon Press 2015 Comparative immunology, microbiology and infectiou Vol.42 No.-

In Vietnam, highly pathogenic avian influenza (HPAI), such as that caused by H5N1 viruses, is the most highly contagious infectious disease that has been affecting domestic poultry in recent years. Vietnam might be an evolutionary hotspot and a potential source of globally pandemic strains. However, few studies have reported viruses circulating in the south-central region of Vietnam. In the present study, 47 H5N1-positive samples were collected from both vaccinated and unvaccinated poultry farms in the South Central Coast region of Vietnam during 2013-2014, and their genetic diversity was analyzed. A common sequence motif for HPAI virus was identified at HA-cleavage sites in all samples: either RERRRKR/G (clades 2.3.2.1c and 2.3.2.1a) or REGRRKKR/G (clade 1.1.2). Phylogenetic analysis of HA genes identified three clades of HPAI H5N1: 1.1.2 (n=1), 2.3.2.1a (n=1), and 2.3.2.1c (n=45). The phylogenetic analysis indicated that these Vietnamese clades may have evolved from Chinese and Cambodian virus clades isolated in 2012-2013 but are less closely related to the clades detected from the Tyva Republic, Bulgaria, Mongolia, Japan, and Korea in 2009-2011. Detection of the coexistence of virus clades 2.3.2.1 and the very virulent 1.1.2 in the south-central regions suggests their local importance and highlights concerns regarding their spread, both northwards and southwards, as well as the potential for reassortment. The obtained data highlight the importance of regular identification of viral evolution and the development and use of region-specific vaccines.

Decomposition of hydrogen sulfide (H₂S) on Ni(100) and Ni₃Al(100) surfaces from first-principles

Hernandez, J.M.,Lim, D.H.,Nguyen, H.V.P.,Yoon, S.P.,Han, J.,Nam, S.W.,Yoon, C.W.,Kim, S.K.,Ham, H.C. Pergamon Press ; Elsevier Science Ltd 2014 International journal of hydrogen energy Vol.39 No.23

Spin-polarized density functional theory studies of hydrogen sulfide (H<SUB>2</SUB>S) adsorption and decomposition on Ni(100) and Ni<SUB>3</SUB>Al(100) surfaces were conducted to understand the aluminum (Al) alloying effect on H<SUB>2</SUB>S dissociation. For such purpose, we first determined the near surface structure of fully ordered Ni<SUB>3</SUB>Al alloy along the [100] direction by calculating the Al segregation energy to the surface and then examined the adsorption energies of the adsorbates (H<SUB>2</SUB>S, HS, S, and H) and the activation barriers for the H<SUB>2</SUB>S and HS decomposition by using Climbing Image-Nudged Elastic Band method. We found that regardless of the way to terminate the surface, Al atom in bimetallic Ni<SUB>3</SUB>Al(100) tends to exist in the first surface layer, rather than in the second or third layer, and the Ni<SUB>3</SUB>Al(100) surface can substantially retard the H<SUB>2</SUB>S decomposition by reducing the adsorption energy of sulfur compounds compared to the pure Ni(100) case. Finally, we presented how the Al in Ni<SUB>3</SUB>Al modifies the activity of surface Ni atoms toward the sulfur compounds by calculating the local density of states and charge distribution in alloying components. This work hints the importance of knowing how to properly tailor the reactivity of Ni based materials to enhance the resistance for sulfur poisoning.

Influence of a cocktail of protease and xylanase in different energy densities of corn- and soybean-meal-based diet on growth performance, nutrient digestibility, carcass quality, and gas emission in broilers

Nguyen, D.H.,Tran, H.N.,Yun, H.M.,Kim, I.H.,Plaizier, J. Canadian Science Publishing 2018 Canadian journal of animal science Vol.98 No.2

<P> A total of 480 one-day-old male Ross 308 broilers with an average initial body weight (BW) of 42 ± 1 g was randomly divided into four treatments (8 replicates/treatment, 15 birds/replicate) by their BW to evaluate the influence of a cocktail of protease and xylanase in different energy density of corn- and soybean-meal-based diet on broilers. This experiment lasted for 35 d and there were two phases; starter (1-18 d) and finisher (19-35 d). The experiment was a 2 × 2 factorial arrangement with two levels of metabolizable energy and the cocktail enzyme with 200 mg of protease kg<SUP>−1</SUP> diet and 100 FXU xylanase kg<SUP>−1</SUP> diet. Both high-nutrient density and cocktail enzyme supplementation increased (P @@<@@ 0.05) the body weight gain (BWG) during day 1-18 and day 1-35 as well as dry matter retention on day 35. Broilers fed the high-nutrient-density diets had higher (P @@<@@ 0.05) energy retention on day 35 and relative breast muscle weight. Broilers fed the cocktail enzyme diets significantly increased nitrogen (N) retention and decreased the levels of ammonia (NH3) and hydrogen sulphide (H2S) emission. In conclusion, dietary supplementation of the cocktail enzyme component improved BWG, N retention, and reduced excreta noxious gas emission in broilers. </P>

Combination of plasmas and catalytic reactions for CO₂ reforming of CH₄ by dielectric barrier discharge process

Nguyen, H.H.,Kim, K.S. Elsevier Science Publishers 2015 CATALYSIS TODAY - Vol.256 No.1

Dry reforming of methane that converts two green-house gases (CH<SUB>4</SUB> and CO<SUB>2</SUB>) to syngas (mixture of CO and H<SUB>2</SUB>) has gained a great research interests. In this research, we investigated the CO<SUB>2</SUB> reforming of CH<SUB>4</SUB> to syngas by the combination of dielectric barrier discharge (DBD) plasmas and zeolite catalyst particles, which was effective in converting the CO<SUB>2</SUB> and CH<SUB>4</SUB> into syngas. The effects of peak voltage applied to plasmas, total gas flow rate and input CO<SUB>2</SUB>/CH<SUB>4</SUB> molar ratio on CO<SUB>2</SUB> and CH<SUB>4</SUB> conversions and H<SUB>2</SUB> and CO selectivities were investigated. The product gases were mainly composed of H<SUB>2</SUB> and CO with some generation of by-products. The conversion efficiencies of CO<SUB>2</SUB> and CH<SUB>4</SUB> in DBD plasmas with zeolite catalyst increased by the increase of voltage applied to plasmas. The selectivities of CO and H<SUB>2</SUB> depend largely on the voltage applied to the plasmas and the ratio of CO<SUB>2</SUB> to CH<SUB>4</SUB>, but did not depend significantly on the changes of frequency and total gas flow rate.

Antiviral phenolics from the leaves of Cleistocalyx operculatus

Ha, T.K.Q.,Dao, T.T.,Nguyen, N.H.,Kim, J.,Kim, E.,Cho, T.Oh.,Oh, W.K. Elsevier 2016 Fitoterapia Vol.110 No.-

<P>During the screening program for anti-influenza agents from medicinal plants, the ethanolic extract of Cleistocalyx operculatus leaves was found to exhibit potential neuraminidase (NA) inhibitory activity. Bioassay directed fractionation led to the isolation of two new acetophenones (1 and 2) and one new flavanone (3), along with six known compounds (4-9). The structures of all isolated compounds were elucidated using various spectroscopic methods and through comparison with the previous literature. Compounds 6 and 8 exhibited strong enzymatic inhibition on various neuraminidases from different influenza viruses, including H1N1, H9N2, novel H1N1, and oseltamivir-resistant novel H1N1 (H274Y mutation) expressed in HEM293 cells (IC50 values ranging from 5.07 +/- 0.94 mu M to 9.34 +/- 2.52 mu M, respectively). Kinetic experiments revealed the non-competitive inhibitory mode of both compounds 6 and 8. Furthermore, these flavonoids reduced the cytopathic effect of the H1N1 virus in MDCK cells. The present study suggests the potential of two flavonoids (6 and 8) as new lead compounds for the development of novel NA inhibitors in the future. (C) 2016 Elsevier B.V. All rights reserved.</P>

Synthesis and biological evaluation of C-ring truncated deguelin derivatives as heat shock protein 90 (HSP90) inhibitors

Kim, H.S.,Hong, M.,Ann, J.,Yoon, S.,Nguyen, C.T.,Lee, S.C.,Lee, H.Y.,Suh, Y.G.,Seo, J.H.,Choi, H.,Kim, J.Y.,Kim, K.W.,Kim, J.,Kim, Y.M.,Park, S.J.,Park, H.J.,Lee, J. Elsevier/Pergamon 2016 Bioorganic & medicinal chemistry Vol.24 No.22

Based on the lead compound L-80 (compound 2), a potent heat shock protein 90 (HSP90) inhibitor, a series of C-ring truncated deguelin analogs were designed, synthesized and evaluated for Hypoxia Inducible Factor-1α (HIF-1α) inhibition as a primary screening method. Their structure-activity relationship was investigated in a systematic manner by varying the A/B ring, linker and D/E ring, respectively. Among the synthesized inhibitors, compound 5 exhibited potent HIF-1α inhibition in a dose-dependent manner and significant antitumor activity in human non-small cell lung carcinoma (H1299), with better activities than L-80. It also inhibited in vitro hypoxia-mediated angiogenic processes in human retinal microvascular endothelial cells (HRMEC). The docking study of 5 showed a similar binding mode as L-80: it occupied the C-terminal ATP-binding pocket of HSP90, indicating that the anticancer and antiangiogenic activities of 5 were derived from HIF-1α destabilization by inhibiting the C-terminal ATP-binding site of hHSP90.

The reproduction potentials of four entomopathogenic nematode strains related to cost-effective production for biological control

Chau Nguyen N.,Anh Le T.,Vu Nguyen H.,Phuc Hoang K. 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.2

Bioassays to evaluate the mortality, virulence and reproduction potentials of four indigenous EPN strains, SPQ16, S-BM12, H-KT3987 and H-CB3452 on insect larvae of mealworm (Tenebrio molitor) and greater wax moth (Galleria mellonella) revealed the highest mortality rates of two insect larvae at the highest inoculation dose of 100 IJs to range from 89 to 100 percent and 94.3–100 percent at 48 h after inoculation, respectively. Virulence was high for all nematode strains, with LC 50 values between 29.6 and 47.3 IJs/insect host. The highest IJ yields were different between nematode strains and insect host, from 66.8 × 10 3 IJs (S-PQ16) to 118.6 × 10 3 IJs (HKT3987) on T. molitor, and from 54.2 × 10 3 IJs (S-BM12) to 163.3 × 10 3 IJs (H-KT3987) on G. mellonella. The culturing cost in terms of food expenditure for rearing insect larvae varied between insect larvae and nematode strains, from 6.76 to 26.63 USD per billion IJs for nematode strains cultured on T. molitor larvae and from 3.54 to 7.81 USD per billion IJs for nematode strains cultured on G. mellonella larvae. The full cost for a nematode product of 2.5 × 10 9 IJs per hectare, produced through in vivo mass culturing, of the most efficient nematode strain, H-KT3987, was 191.3 USD, slightly cheaper than 199.4 USD for the same nematode product produced through in vitro mass culturing.

Fabrication of flexible, transparent silver nanowire electrodes for amperometric detection of hydrogen peroxide

Lee, J.H.,Huynh-Nguyen, B.C.,Ko, E.,Kim, J.H.,Seong, G.H. Elsevier Sequoia 2016 Sensors and actuators. B Chemical Vol.224 No.-

We present a simple method to fabricate flexible, transparent silver nanowire (AgNW) films. Homogenous AgNW networks were formed on a mixed cellulose ester (MCE) membrane by vacuum filtration and were easily transferable to self-adhesive poly(ethylene terephthalate). The opaque, white MCE membrane became transparent after being subjected to hot acetone vapor. The fabricated AgNW films had an average resistivity of 13Ω/sq and a transmittance of approximately 67%. Moreover, the AgNW films showed excellent mechanical properties in repeated adhesion tests and bending tests. The AgNW films also showed good resistance against heat and NaCl solutions. AgNW films were patterned by a combination of soft lithography and a solution-based chemical etching technique. The area under the photoresist polymer maintained its conductivity and transmittance after etching, whereas increased resistance and transparency were observed in the etched area. The suitability of the patterned AgNW electrodes for electronic devices was demonstrated via a simple LED chip array. After using standard photolithography to define the working area, AgNW films were used as sensor electrodes for the electrochemical detection of hydrogen peroxide (H<SUB>2</SUB>O<SUB>2</SUB>). The AgNW sensors displayed a reasonable detection limit of 46μM (S/N=3), a rapid response time (within 2s), and high sensitivity (749μAmM<SUP>-1</SUP>cm<SUP>-2</SUP> and 1640μAmM<SUP>-1</SUP>cm<SUP>-2</SUP>). Furthermore, the AgNW sensor was resistant to other potential interfering electroactive species commonly present in physiological samples such as l-ascorbic acid, glucose, and sodium oxalate. These results indicate that the AgNW sensor is selective for electroreduction of H<SUB>2</SUB>O<SUB>2</SUB>. Additionally, the developed sensor exhibited a stable amperometric response to the reduction of H<SUB>2</SUB>O<SUB>2</SUB> even after extended storage.

Targeted and controlled drug delivery system loading artersunate for effective chemotherapy on CD44 overexpressing cancer cells

Tran, T. H.,Nguyen, T. D.,Nguyen, H.,Nguyen, H. T.,Kim, J. O.,Yong, C. S.,Nguyen, C. N. Springer Science + Business Media 2016 Archives of Pharmacal Research Vol.39 No.5

<P>Poly(d,l-lactic-co-glycolic acid) (PLGA) nanoparticles with negative surface charge were reversed to positive by cationic surfactant-DDAB before being coated with an anionic polymer, hyaluronic acid, to improve their site-specific intracellular delivery against CD44 receptor overexpressing cancer cells. Incorporating artesunate (ART)-a promising anticancer drug into PLGA/HA nanoparticles, is expected not only to overcome its poor aqueous solubility and stability but also enhance the activities. The obtained particles were characterized by dynamic light scattering, zeta potential measurements, and transmission electron microscopy (TEM). Cancer cell internalization of the NPs was evaluated by flow cytometry and cytotoxicity of the NPs was tested by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assay. PLGA/HA nanoparticles showed greater extent of cellular uptake to SCC-7 and MCF-7 cells, indicating their affinity with CD44 receptor-mediated endocytosis. Almost 60 % of ART was released into the outer media after 48 h. In vitro fluorescence sorting demonstrated that PLGA/HA had highly efficient targeting and accumulation into CD44 receptor overexpression cells. The significant reduction in cell viability as well as greater induction of apoptosis suggested a potential in anticancer therapy of ART loaded PLGA/HA.</P>