The potential efficacy of the E2-subunit vaccine to protect pigs against different genotypes of classical swine fever virus circulating in Vietnam

Ha Thi Thanh Tran,Duc Anh Truong,Viet Duc Ly,Hao Thi Vu,Tuan Van Hoang,Chinh Thi Nguyen,Nhu Thi Chu,Vinh The Nguyen,Duyen Thuy Nguyen,Kohtaroh Miyazawa,Takehiro Kokuho,Hoang Vu Dang 대한백신학회 2020 Clinical and Experimental Vaccine Research Vol.9 No.1

Purpose: To date, many kinds of classical swine fever (CSF) vaccines have been developed to protect against this disease. However, the efficacy of these vaccines to protect the pig against field CSF strains needs to be considered, based on circulating strains of classical swine fever virus (CSFV). Materials and Methods: Recombinant E2-CSFV protein produced by baculovirus/insect cell system was analyzed by western blots and immunoperoxidase monolayer assay. The effect of CSFV-E2 subunit vaccines was evaluated in experimental pigs with three genotypes of CSFV challenge. Anti-E2 specific and neutralizing antibodies in experimental pigs were analyzed by blocking enzyme-linked immunosorbent assay and neutralization peroxidize-linked assay. Results: The data showed that CSFV VN91-E2 subunit vaccine provided clinical protection in pigs against three different genotypes of CSFV without noticeable clinical signs, symptoms, and mortality. In addition, no CSFV was isolated from the spleen of the vaccinated pigs. However, the unvaccinated pigs exhibited high clinical scores and the successful virus isolation from spleen. These results showed that the E2-specific and neutralizing antibodies induced by VN91-E2 antigen appeared at day 24 after first boost and a significant increase was observed at day 28 (p<0.01). This response reached a peak at day 35 and continued until day 63 when compared to controls. Importantly, VN91-E2 induced E2-specific and neutralizing antibodies protected experimental pigs against high virulence of CSFVs circulating in Vietnam, including genotype 1.1, 2.1, and 2.2. Conclusion: These findings also suggested that CSFV VN91-E2 subunit vaccine could be a promising vaccine candidate for the control and prevention of CSFV in Vietnam.

An improvement of real-time polymerase chain reaction system based on probe modification is required for accurate detection of African swine fever virus in clinical samples in Vietnam

Tran Ha Thi Thanh,Dang Anh Kieu,Ly Duc Viet,Vu Hao Thi,Hoang Tuan Van,Nguyen Chinh Thi,Chu Nhu Thi,Nguyen Vinh The,Nguyen Huyen Thi,Truong Anh Duc,Pham Ngoc Thi,Dang Hoang Vu 아세아·태평양축산학회 2020 Animal Bioscience Vol.33 No.10

Objective: The rapid and reliable detection of the African swine fever virus (ASFV) plays an important role in emergency control and preventive measures of ASF. Some methods have been recommended by FAO/OIE to detect ASFV in clinical samples, including real-time polymerase chain reaction (PCR). However, mismatches in primer and probe binding regions may cause a false-negative result. Here, a slight modification in probe sequence has been conducted to improve the qualification of real-time PCR based on World Organization for Animal Health (OIE) protocol for accurate detection of ASFV in field samples in Vietnam. Methods: Seven positive confirmed samples (four samples have no mismatch, and three samples contained one mutation in probe binding sites) were used to establish novel real-time PCR with slightly modified probe (Y = C or T) in comparison with original probe recommended by OIE. Results: Both real-time PCRs using the OIE-recommended probe and novel modified probe can detect ASFV in clinical samples without mismatch in probe binding site. A high correlation of cycle quantification (Cq) values was observed in which Cq values obtained from both probes arranged from 22 to 25, suggesting that modified probe sequence does not impede the qualification of real-time PCR to detect ASFV in clinical samples. However, the samples with one mutation in probe binding sites were ASFV negative with OIE recommended probe but positive with our modified probe (Cq value ranked between 33.12-35.78). Conclusion: We demonstrated for the first time that a mismatch in probe binding regions caused a false negative result by OIE recommended real-time PCR, and a slightly modified probe is required to enhance the sensitivity and obtain an ASF accurate diagnosis in field samples in Vietnam.

A novel mathematical modelling for simulating the spread of heavy metals in solid waste landfills

Ngoc Ha Hoang,Anh My Chu,Kim Thai Thi Nguyen,Chi Hieu Le 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.3

Municipal solid waste (MSW) landfills create the environmental pollutions due to problems related to toxins, leachate, and greenhouse gas, which are the growing environmental concerns, especially in developing countries. This paper presents a novel mathematical modelling for simulating the spread of heavy metals in soil layers in the MSW landfills. A new mathematical modelling procedure is studied for deriving the governing equation which describes the time varying concentration of pollutants in the leachate in a 3-dimensional (3D) space of soil layers. A Finite Element Method (FEM) based algorithm is then constructed to solve numerically the governing equation over time in 3D space for effectively analyzing the variation of pollutants concentrations. Finally, the applicability and advantages of the proposed novel method are demonstrated through the case study with soil samples collected from the actual MSW landfill. The successfully developed algorithm can be applied to model and predict the spread of different heavy metals in the MSW landfill sites; and to develop effective solutions and policies for solid waste classification and management, in order to minimise the negative impacts from the potential risk of the toxic heavy metal pollutions, soil contaminations and groundwater pollutions in the areas nearby the MSW landfill.

Determinants of the Competitiveness of Women-Owned Small- and Medium-Sized Enterprises: An Empirical Study from Vietnam

Tien Ngoc DAO,Ha Thi Thu LE,Phuong Thi Mai CHU,Ngan Hoang PHAM,Trang Thi Dai LUONG,Dung Tri TRAN 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.12

Guided by a resource-based theory, this study is the first one that takes a quantitative approach to identify determinants of competitiveness of women-owned small and medium enterprises (SMEs) in Vietnam. The study employs time series data of Vietnamese SMEs extracted from the Vietnam Small and Medium Enterprises Survey conducted biennially from 2005 to 2015 in ten Vietnamese provinces. Firm competitiveness hereby is indicated by revenue, market share, profitability, and export volume. The research reveals a number of determining factors, of all, research and development, labor skills, business environment, technology investment are the most important factors, followed by capital and headcount. It is indicated that the determining factors have different influences on competitiveness obtained by different measurements. Therefore, it is based on specific targets and situations to make wise business decisions. The authors also make comparisons among groups of women-owned enterprises divided by their firm age, location, ownership, export, age, and educational background of business owners. The findings serve as critical empirical evidence and provide policy recommendations for improving the competitiveness of women-owned SMEs in Vietnam. The recommendations range from technology support, education and professional support for female entrepreneurs, access to capital and human resources to business environment improvement.

Genome‑wide identification, organization, and expression profiles of the chicken fibroblast growth factor genes in public databases and Vietnamese indigenous Ri chickens against highly pathogenic avian influenza H5N1 virus infection

Truong Anh Duc,Tran Ha Thi Thanh,Chu Nhu Thi,Nguyen Huyen Thi,부 티 하오,Hong Yeojin,송기덕,Dang Hoang Vu,홍영호 아세아·태평양축산학회 2023 Animal Bioscience Vol.36 No.4

Objective: Fibroblast growth factors (FGFs) play critical roles in embryo development, and immune responses to infectious diseases. In this study, to investigate the roles of FGFs, we performed genome-wide identification, expression, and functional analyses of FGF family members in chickens. Methods: Chicken FGFs genes were identified and analyzed by using bioinformatics approach. Expression profiles and Hierarchical cluster analysis of the FGFs genes in different chicken tissues were obtained from the genome-wide RNA-seq. Results: A total of 20 FGF genes were identified in the chicken genome, which were classified into seven distinct groups (A-F) in the phylogenetic tree. Gene structure analysis revealed that members of the same clade had the same or similar exon-intron structure. Chromosome mapping suggested that FGF genes were widely dispersed across the chicken genome and were located on chromosomes 1, 4-6, 9-10, 13, 15, 28, and Z. In addition, the interactions among FGF proteins and between FGFs and mitogen‑activated protein kinase (MAPK) proteins are limited, indicating that the remaining functions of FGF proteins should be further investigated in chickens. Kyoto encyclopedia of genes and genomes pathway analysis showed that FGF gene interacts with MAPK genes and are involved in stimulating signaling pathway and regulating immune responses. Furthermore, this study identified 15 differentially expressed genes (DEG) in 21 different growth stages during early chicken embryo development. RNA-sequencing data identified the DEG of FGFs on 1- and 3-days post infection in two indigenous Ri chicken lines infected with the highly pathogenic avian influenza virus H5N1 (HPAIV). Finally, all the genes examined through quantitative real-time polymerase chain reaction and RNA-Seq analyses showed similar responses to HPAIV infection in indigenous Ri chicken lines (R2 = 0.92– 0.95, p<0.01). Conclusion: This study provides significant insights into the potential functions of FGFs in chickens, including the regulation of MAPK signaling pathways and the immune response of chickens to HPAIV infections.

Cultural Factors Affecting Tendency of Ethical Decision-Making by Accounting Students: An Empirical Study in Vietnam

Nga Thanh DOAN,Trang Thu TA,Ha Thi Thanh CHU,Anh Thi Quynh LE,May Thi LE,Tuan Hoang PHAM,Thao Thu VUONG 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.2

The purpose of this study is to look at the precise direction and magnitude of cultural elements such as education, gender, power distance, and risk-taking proclivity on ethical decision-making. Data was collected from 194 interviewees in three groups: general business students, accounting major students, and professional auditors in Vietnam. The path analysis is used to test the impact of cultural factors on ethical awareness, ethical judgment, and ethical intention in different dubious scenarios at the personal level as independent variables, intermediate variables, and moderating variables. The metric is the percentage of respondents who believe a particular behavior is unethical based on a set of ethical principles. The researchers used SPSS AMOS software to conduct a confirmatory factor survey to evaluate the convergent and discriminant validity of latent variables. The results show differences between the two groups of students and professionals on these measures, suggesting that all of the four factors have an effect on ethical decision-making. Based on research results, some recommendations are proposed related to the four factors to improve the ethics of future generations of auditors in Vietnam. This study also contributes to the theory of culture in particular and cultural interference in general in the field of accounting-auditing in Vietnam in the process of international integration.

Isolation and Cytotoxic Potency of Endophytic Fungi Associated with Dysosma difformis, a Study for the Novel Resources of Podophyllotoxin

Hoa Thi Tran,Giang Thu Nguyen,Hong Ha Thi Nguyen,Huyen Thi Tran,Quang Hong Tran,Quang Ho Tran,Ngoc Thi Ninh,Phat Tien Do,Ha Hoang Chu,Ngoc Bich Pham 한국균학회 2022 Mycobiology Vol.50 No.5

Endophytic fungi are promising sources for the production of podophyllotoxin-an important anticancer compound, replacing depleted medical plants. In this study, the endophytes asso- ciated with Dysosma difformis-an ethnomedicinal plant species were isolated to explore novel sources of podophyllotoxin. Fifty-three endophytic fungi were isolated and identified by morphological observation and ITS-based rDNA sequencing, assigning them to 27 genera in 3 divisions. Fusarium was found the most prevalent genus with a colonization frequency of 11.11%, followed by Trametes (9.26%) and Penicillium (7.41%). Phylogenetic trees were constructed for the endophytic fungi community in two collection sites, Ha Giang and Lai Chau, revealing the adaptation of the species to the specific tissues and habitats. Cytotoxic activity of endophytic fungal extracts was investigated on cancer cell lines such as SK-LU-1, HL-60, and HepG2, demonstrating strong anti-cancer activity of six isolates belonging to Penicillium, Trametes, Purpureocillium, Aspergillus, and Ganoderma with IC50 value of lower than 10 mg/mL. The presence of podophyllotoxin was indicated in Penicillium, Trametes, Aspergillus and for the first time in Purpureocillium and Ganoderma via high-performance liquid chromatography, which implied them as a potential source of this anti- cancer compound.

Close-Packed Monolayer Self-Assembly of Silica Nanospheres Assisted by Infrared Irradiation

Nguyen Van Minh,Nguyen Thi Hue,Nghiem Thi Ha Lien,Chu Manh Hoang 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.1

In this paper, we report on a fast and cost-effective dropcoating technique for the self-assembly of silica nano-spheresfrom a mono-dispersed colloidal suspension into close-packedmonolayer (CMP) on hydrophilic single-crystal siliconsubstrate. The technique includes the self-assembly of silicanano-spheres on slanted silicon substrate and infraredirradiation during evaporation process of the coated droplet. The influence of the substrate slant angle and infraredirradiation on the formation of silica nano-sphere monolayer isinvestigated. This achievement is promising for variousapplications, such as a mask layer for nano-sphere lithographythat is employed for producing fundamental elements inphotonics, plasmonics, and solar cell.