A real-time RT-PCR for detection of clade 1 and 2 H5N1 Influenza A virus using Locked Nucleic Acid (LNA) TaqMan probes

<p>Abstract</p> <p>Background</p> <p>The emergence and co-circulation of two different clades (clade 1 and 2) of H5N1 influenza viruses in Vietnam necessitates the availability of a diagnostic assay that can detect both variants.</p> <p>Results</p> <p>We developed a single real-time RT-PCR assay for detection of both clades of H5N1 viruses, directly from clinical specimens, using locked nucleic acid TaqMan probes. Primers and probe used in this assay were designed based on a highly conserved region in the <it>HA </it>gene of H5N1 viruses. The analytical sensitivity of the assay was < 0.5 PFU and 10 - 100 ssDNA plasmid copies. A total of 106 clinical samples (58 from patients infected with clade 1, 2.1 or 2.3 H5N1 viruses and 48 from uninfected or seasonal influenza A virus-infected individuals) were tested by the assay. The assay showed 97% concordance with initial diagnostics for H5 influenza virus infection with a specificity of 100%.</p> <p>Conclusions</p> <p>This assay is a useful tool for diagnosis of H5N1 virus infections in regions where different genetic clades are co-circulating.</p

Electrochemical Fabrication of Hybrid Plasmonic-dielectric Nanomaterial Based on Gold-diamond Clusters

Hybrid plasmonic-dielectric material were fabricated by micro-discharge through water sols of sub-micrometer-sized diamonds mixed with HAuCl4 acid. Primary characterization of their deposits on a silicon wafer surface by means of electron microscopy and energy-dispersive x-ray spectroscopy indicate close proximity of gold nanoparticles and diamond particles, which is supported by photoluminescence studies demonstrating strong – almost two-fold – damping of diamond luminescence owing to the attachment of gold nanoparticles. UV-near IR spectroscopy of their sols consistently exhibits small red spectral shifts for the fabricated nanomaterial, comparing to bare gold nanoparticles. Keywords: micro-diamonds, gold nanoparticles, hybrid plasmonic-dielectric material, electrochemical fabrication, electron microscopy and optical characterization.Hybrid plasmonic-dielectric material were fabricated by micro-discharge through water sols of sub-micrometer-sized diamonds mixed with HAuCl4 acid. Primary characterization of their deposits on a silicon wafer surface by means of electron microscopy and energy-dispersive x-ray spectroscopy indicate close proximity of gold nanoparticles and diamond particles, which is supported by photoluminescence studies demonstrating strong – almost two-fold – damping of diamond luminescence owing to the attachment of gold nanoparticles. UV-near IR spectroscopy of their sols consistently exhibits small red spectral shifts for the fabricated nanomaterial, comparing to bare gold nanoparticles

A Research on the Impact of Top Management Commitment and Training on Benefits of Environmental Management System Application in Different Enterprises

This paper aims to investigate the impact of 2 factors in the internal motive (top management commitment and employee training) on three dimensions of benefits (environmental, economic, and social) in enterprises that apply environmental management systems (EMS). The survey collected answers from 258 top-tier and quality managers of ISO 14001 certified enterprises in Vietnam. Research results show that top management commitment impacts economic, social, and environmental benefits. Meanwhile, training only influences environmental and social but not economic benefits. Furthermore, this paper also finds evidence that environmental benefits have impacts on economic and social benefits in the research context of Vietnam. Keywords:ISO 14001, environmental management systems (EMS), environmental benefits, economic benefits, social benefits DOI: 10.7176/JESD/13-7-03 Publication date: April 30th 202

Phenolic Constituents of the Roots of Rhamnoneuron balansae with Senolytic Activity

With the advent of senolytic agents capable of selectively removing senescent cells in old tissues, the perception of age-associated diseases has been changing from being an inevitable to a preventable phenomenon of human life. In the search for materials with senolytic activity from natural products, six new flavonostilbenes (1-6), three new phenylethylchromanones (7-9), three new phenylethylchromones (10-12), and four known compounds (13-16) were isolated from the roots of Rhamnoneuron balansae. The chemical structures of these isolated compounds were determined based on the interpretation of spectroscopic data, including 1D and 2D NMR, ECD, and HRMS. The absolute configuration of compound 1 was also determined by a Mosher ester analysis and ECD calculations. Compounds 6-8 were shown to selectively destroy senescent cells, and the promoter activity of p16INK4A, a representative senescence marker, was reduced significantly by compound 6. The present results suggest the potential activity of flavonostilbene and phenylethylchromanone skeletons from R. balansae as new senolytics.N

Benzylisoquinoline Alkaloids from the Stems of Limacia scandens and Their Potential as Autophagy Inhibitors

Limacia scandens is traditionally used to treat depression and affective disorders in Malaysia. The chemical compositions have been reported to include bisbenzylisoquinoline and aporphine-type alkaloids in the genus Limacia Lour., but studies on the components of L. scandens have rarely been reported. Therefore, this study was conducted to determine new benzylisoquinoline alkaloid derivatives with autophagy regulation activity from this plant. Bioactivity-guided isolation was applied to various column chromatography methods using RP-18, Sephadex LH-20 open column chromatography, and preparative HPLC. The chemical structures of the isolated compounds were elucidated through spectroscopic data analysis, including NMR, HR-ESI-MS, and ECD data. In addition, isolated compounds were tested for autophagy-regulating activity in HEK293 cells expressing GFP-L3. Three new dimeric benzylisoquinoline alkaloids (1-3), one new 4-hydroxybenzoic acid-conjugated benzylisoquinoline alkaloid (4), and six known compounds (5-10) were isolated from the stems of L. scandens. All compounds (1-10) were screened for autophagy regulation in HEK293 cells stably expressing the GFP-LC3 plasmid. Among the isolated compounds, 1, 2, and 4 showed autophagic regulation activity that blocked the process of combining autophagosomes and lysosomes. They also inhibit the protein degradation process from the autolysosome as inhibitors of autophagy. Novel benzylisoquinoline alkaloids from L. scandens showed potent potency for the inhibition of autophagic flux. This study provides potential candidates for developing natural autophagy inhibitors for disease prevention and treatment.Y

Pyrene degradation of biofilm-forming Paracoccus sp. DG25 isolated from oil polluted samples collected in petroleum storage Duc Giang, Hanoi: Research article

In this study, a well biofilm-forming bacterial strain was isolated from oil contaminated water and sediment samples collected in petroleum storage Duc Giang, Hanoi. It was identified as Paracoccus sp. DG25 and registered in the GenBank database with the accession numbers KJ608354. Several biophysical and bio-chemical conditions for the biofilm formation of the strain were estimated such as pH, temperature, carbon sources and nitrogen sources. As the results the biofilm forming capacity was highest at pH 7, 37 oC, on maltose and supplemented with KNO3. Using these optimal conditions, the formed biofilm degraded 76.07 % of pyrene after 7 day-incubation, with the initial concentration of 300 ppm by high-performance liquid chromatography (HPLC) analysis. To our knowledge, there is rare publication on pyrene degradation by biofilm-forming bacteria. Therefore, the obtained results show that biofilm formed the strain Paracoccus sp. DG25 may considerably increase the degrading efficiency of pyrene and may lead to a new approach to treat polycyclic aromatic hydrocarbons containing in petroleum oil contaminated water in Vietnam.Trong nghiên cứu này, từ các mẫu đất và nước nhiễm dầu lấy tại kho xăng Đức Giang, Hà Nội, chúng tôi đã phân lập được chủng vi khuẩn có khả năng tạo màng sinh học tốt. Chủng vi khuẩn này đã được phân loại và định tên là Paracoccus sp. DG25 với số đăng ký trên ngân hàng Gen là KJ608354. Chúng tôi cũng đã nghiên cứu một số điều kiện hóa lý ảnh hưởng tới khả năng hình thành màng sinh học như pH, nhiệt độ, nguồn Carbon và nguồn Nitơ. Kết quả cho thấy, chủng DG25 có khả năng tạo màng tốt nhất ở các điều kiện pH 7, 37 oC, nguồn Carbon là maltose và nguồn Nitơ là KNO3. Sử dụng các điều kiện tối ưu này để tạo màng và đánh giá khả năng phân hủy pyrene của màng tạo thành. Bằng phương pháp sắc ký lỏng cao áp, chúng tôi đã đánh giá được hàm lượng pyrene bị phân hủy sau 7 ngày nuôi tĩnh bởi màng sinh học của chủng DG25 lên tới 76,07 % với nồng độ ban đầu là 300 ppm. Cho tới nay, chưa có nhiều công bố về hiệu quả phân hủy pyrene của các chủng vi khuẩn tạo màng sinh học. Do vậy, kết quả đạt được này mở ra khả năng sử dụng màng tạo thành bởi chủng DG25 để nâng cao hiệu quả phân hủy pyren và có thể mở ra phương pháp mới nhằm xử lý các hợp chất hydrocarbon thơm có trong nước ô nhiễm dầu ở Việt Nam

Outbreak investigation for COVID-19 in northern Vietnam

Two Vietnamese adults returned to their home province of Vinh Phuc in northern Vietnam on Jan 17, 2020, from Wuhan, China, where they had been living since Nov 15, 2019, for a business trip. They presented with mild respiratory symptoms to their local health facilities at 4 days and 8 days, respectively, after arrival in Vinh Phuc. Both individuals were initially placed into respiratory isolation in hospital. Case 1 tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative organism of coronavirus disease 2019 (COVID-19), on Jan 30, 2020, and remained in isolation until recovery. Case 2 was discharged from isolation in hospital after having one negative test result on Jan 28 (11 days after returning from Wuhan). Following discharge, the patient attended a family social function. 2 days later, she was readmitted after a second nasal swab for SARS-CoV-2 taken during her time in hospital was reported as positive