Two new species of Camellia (Theaceae) from Vietnam

Lieu Thi Nguyen,Ninh Tran,Uematsu CHIYOMI,Katayama HIRONORI,Dung Van Luong,Son Thanh Hoang,Ky Danh NGUYEN,Hung Viet NGUYEN,Toan Canh THAI 한국식물분류학회 2018 식물 분류학회지 Vol.48 No.2

Two new species of Camellia (Theaceae) are described from Vietnam: Camellia vuquangensis Luong, Tran & L. T. Nguyen and Camellia hatinhensis Luong, Tran & L. T. Nguyen. The new taxa were col- lected from Vu Quang National Park in the center of Vietnam. The new finds are morphologically dissimilar to all known Camellia species. Recent Camellia discoveries have increased the number of species recorded in Viet- nam from 50 to 75, making Vietnam a center of diversity and a crucial area for more research into the diversity and distributions of Camellia.

Identification of Soluble Epoxide Hydrolase Inhibitors from the Seeds of Passiflora edulis Cultivated in Vietnam

To Dao Cuong,Hoang Thi Ngoc Anh,Tran Thu Huong,Pham Ngoc Khanh,Vu Thi Ha,Tran Manh Hung,김영호,Nguyen Manh Cuong 한국생약학회 2019 Natural Product Sciences Vol.25 No.4

Soluble epoxide hydrolases (sEH) are enzymes present in all living organisms, metabolize epoxy fatty acids to 1,2-diols. sEH in the metabolism of polyunsaturated fatty acids plays a key role in inflammation. In addition, the endogenous lipid mediators in cardiovascular disease are also broken down to diols by the action of sEH that enhanced cardiovascular protection. In this study, sEH inhibitory guided fractionation led to the isolation of five phenolic compounds trans-resveratrol (1), trans-piceatannol (2), sulfuretin (3), (+)-balanophonin (4), and cassigarol E (5) from the ethanol extract of the seeds of Passiflora edulis Sims cultivated in Vietnam. The chemical structures of isolated compounds were determined by the interpretation of NMR spectral data, mass spectra, and comparison with data from the literature. The soluble epoxide hydrolase (sEH) inhibitory activity of isolated compounds was evaluated. Among them, trans-piceatannol (2) showed the most potent inhibitory activity on sEH with an IC50 value of 3.4 mM. This study marks the first time that sulfuretin (3) was isolated from Passiflora edulis as well as (+)-balanophonin (4), and cassigarol E (5) were isolated from Passiflora genus.

Four novel mutations in the androgen receptor gene from Vietnamese patients with androgen insensitivity syndrome

Nguyen Thu Hien,Nguyen Duc Quan,Kim Lien Nguyen Thi,Thi Thanh Ngan Nguyen,Nguyen Thi Phuong Mai,Tran Ngoc Dung,Nguyen Huy Hoang 한국유전학회 2023 Genes & Genomics Vol.45 No.4

Background Androgens and androgen receptor (AR) are critical regulators of the masculinization process in male sexual development. The absence of a functioning AR results in the development of the androgen insensitivity syndrome (AIS), a rare disorder of sexual development (DSD) characterized by the external genitalia feminization, gynecomastia, and impaired spermatogenesis. Objective To determine the AR gene mutations associated with male DSD in four unrelated Vietnamese patients. Methods To detect the disease-causing mutations, whole exome sequencing (WES) was performed on four patients diagnosed with AIS. Sanger sequencing was then used for validation of the identified mutations. Finally, 12 web-based tools, three-dimensional protein modeling software, and the guidelines issued by the American College of Medical Genetics and Genomics were used to assess the potential pathogenicity of these mutations. Results Four distinct novel mutations, namely c.1834T > A (p.Cys612Ser), c.2122 C > G (p.Leu708Val), c.2630T > G (p.Phe877Cys), and c.2641 C > A (p.Leu881Met) in the AR gene, were identified in four AIS patients using WES. The in silico analysis results revealed that the Cys612, Leu708, Phe877, and Leu881 sites are important for an appropriate response to androgens of the AR, and mutation at these sites can have adverse effects on the AR functions, androgen–AR interaction, and AR signaling pathway. Conclusions WES and in silico analyses strongly suggested that four novel AR mutations are pathogenic and have led to the development of AIS in the four Vietnamese patients under consideration.

Uptake of arsenic and heavy metals by native plants growing near Nui Phao multi-metal mine, northern Vietnam

Ha, Nguyen Thi Hoang,Ha, Nguyen Thi,Nga, Tran Thi Huyen,Minh, Nguyen Ngoc,Anh, Bui Thi Kim,Hang, Nguyen Thi An,Duc, Nguyen Anh,Nhuan, Mai Trong,Kim, Kyoung-Woong Elsevier 2019 Applied geochemistry Vol.108 No.-

<P><B>Abstract</B></P> <P>Phytoremediation is a plant-based, environment-friendly, and cost-effective technology that can be potentially used to remediate contaminated media. This study was conducted to evaluate the phytoextraction and phytostabilization potential, two common techniques of phytoremediation, of 21 plant species growing naturally at the largest tungsten (W) mine in Vietnam—the second largest production of W in the world. The average concentrations in different soil fractions were in the following order: residue > organically complexed, Fe- and Mn oxide-bound > carbonate bound > exchangeable. The total concentrations of arsenic (As), cadmium (Cd), copper (Cu), and zinc (Zn) in the soil varied by 34–3390, 4.87–81.6, 14.3–2080, and 21.9–370 mg/kg, respectively. The concentrations of As, Cd, Cu, and Zn in the shoots ranged 0.71–2400, 0.05–5.55, 4.81–249, and 13.3–380 mg/kg-DW, respectively. The concentrations of As and Cd in all soil samples and Cu in 70% of soil samples collected around the mine fluctuated within 2–227, 3–54, and up to 21-folds higher than the maximum allowable limit for agricultural soils in Vietnam (QCVN 03-MT:2015/BTNMT). The results indicated that hyperaccumulation levels (mg/kg-DW) were obtained for only As in <I>Pityrogramma calomelanos</I> (2400) and <I>Pteris vittata</I> L. (1860). Based on the recorded hyperaccumulation levels, translocation and accumulation factors, biomass, and fast growth of these plants, <I>P. calomelanos</I> and <I>P. vittata</I> were considered to be promising native plants for the phytoextraction of As contaminated soils. <I>Bidens pilosa</I> L. also has great potential for phytostabilization of mining soils contaminated with As and heavy metals.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Soils near multi-metal (W–F–Cu–Au–Bi) mine were contaminated with As, Cd, Cu. </LI> <LI> Arsenic in shoots were in order of Fern > Monocotyledonae > Dicotyledonae. </LI> <LI> <I>Pityrogramma calomelanos</I> and <I>Pteris vittata</I> L. suggested for phytoextraction of As. </LI> <LI> <I>Bidens pilosa</I> L. suggested for the phytostabilization of mining contaminated soils. </LI> </UL> </P>

Drug resistance and the genotypic characteristics of rpoB and katG in rifampicin- and/or isoniazid-resistant Mycobacterium tuberculosis isolates in central Vietnam

Thi Binh Nguyen Nguyen,Thi Kieu Diem Nguyen,Van Hue Trương,Thi Tuyet Ngoc Tran,van Bao Thang Phan,Thi Tuyen Nguyen,Hoang Bach Nguyen,Viet Quynh Tram Ngo,Van Tuan Mai,Paola Molicotti 질병관리본부 2023 Osong Public Health and Research Persptectives Vol.14 No.5

Objectives: Tuberculosis (TB) and drug-resistant TB (DR-TB) are national health burdens in Vietnam. In this study, we investigated the prevalence of rifampicin (RIF) and/or isoniazid (isonicotinic acid hydrazide, INH) resistance in patients with suspected TB, and applied appropriate techniques to help rapidly target DR-TB. Methods: In total, 1,547 clinical specimens were collected and cultured using the BACTEC MGIT system (Becton Dickinson and Co.). A resazurin microtiter assay (REMA) was used to determine the proportions of RIF and/or INH resistance. A real-time polymerase chain reaction panel with TaqMan probes was employed to identify the mutations of rpoB and katG associated with DR-TB in clinical isolates. Genotyping of the identified mutations was also performed. Results: A total of 468 Mycobacterium tuberculosis isolates were identified using the REMA. Of these isolates, 106 (22.6%) were found to be resistant to 1 or both antibiotics. Of the resistant isolates, 74 isolates (69.8%) were resistant to isoniazid (INH) only, while 1 isolate (0.94%) was resistant to RIF only. Notably, 31 isolates (29.24%) were resistant to both antibiotics. Of the 41 phenotypically INH-resistant isolates, 19 (46.3%) had the Ser315Thr mutation. There were 8 different rpoB mutations in 22 (68.8%) of the RIF-resistant isolates. The most frequently detected mutations were at codons 531 (37.5%), 526 (18.8%), and 516 (6.3%). Conclusion: To help prevent new cases of DR-TB in Vietnam, it is crucial to gain a comprehensive understanding of the genotypic DR-TB isolates.

The extraction of lignocelluloses and silica from rice husk using a single biorefinery process and their characteristics

Ngoc Thuy Nguyen,Nhat Thong Tran,Tan Phat Phan,Anh Thu Nguyen,My Xuyen T. Nguyen,Nguyen Ngan Nguyen,Young Ho Ko,Dai Hai Nguyen,Tran T.T. Van,DongQuy Hoang 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.108 No.-

While the efficient usage of biomass waste can significantly help in addressing environmental issues,there are only a few reports that discuss about processing such waste effectively at a low-cost. Such challengearises from the strong association between the components biomass. In this study, an abundantagricultural byproduct, rice husk (RH), was used as the starting resource. A simple biorefining processof alkaline peroxide treatment followed by acid precipitation and ethanol extraction was performed onRH to obtain cellulose, hemicellulose, lignin, and silica. The chemical structures, morphologies, andphysic-chemical properties of the separated components were identified through a wide range of characterizationapproaches. The final products obtained from of this process were (i) bundles of fiber-likecellulose with a fiber width of 6 mm and (ii) small particles of hemicellulose and lignin with nonuniformshapes. The lignocelluloses products had over 90 wt% carbon with 52.28% crystalline ratio. Meanwhile, the other products comprising hemicelluloses, lignin, and silica were amorphous. The outcomeof this study contributes to expanding and developing the simple and efficient conversion processof biomass waste into sustainable value-added materials. It is crucial to reduce the environmental impactby using renewable materials as the new building block resources for synthetic chemicals.

A Combination of Independent Component Analysis, Relative Wavelet Energy, and Support Vector Machine for Mental State Classification

Hoang-Anh T. Nguyen,Huy-Hoang Tran,Thang T. Vu,T.T. Quyen Bui 제어로봇시스템학회 2016 제어로봇시스템학회 국제학술대회 논문집 Vol.2016 No.10

Mental state classification is an important step for realizing a control system based on electroencephalography (EEG) signals which could benefit a lot of paralyzed people including the locked-in or Amyotrophic Lateral Sclerosis. Considering that EEG signals are nonstationary and often contaminated by various types of artifacts, classifying thoughts into correct mental states is not a trivial problem. In this work, our contribution is that we present and realize a novel model which integrates different techniques: Independent component analysis (ICA), relative wavelet energy, and support vector machine (SVM) for the same task. We applied our model to classify thoughts in two types of experiment whether with two or three mental states. The experimental results show that the presented model outperforms other models using Artificial Neural Network, K-Nearest Neighbors, etc.

Tobacco Control Policies in Vietnam: Review on MPOWER Implementation Progress and Challenges

Hoang, Van Minh,Tran, Thu Ngan,Vu, Quynh Mai,Nguyen, Thi Tuyet My,Le, Hong Chung,Vu, Duy Kien,Tran, Tuan Anh,Nguyen, Bao Ngoc,Vu, Van Giap,Nguyen, Manh Cuong,Pham, Duc Manh,Kim, Bao Giang Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.no.sup1

In Vietnam, the WHO Framework Convention on Tobacco Control (WHO FCTC) took effect in March 2005 while MPOWER has been implemented since 2008. This paper describes the progress and challenges of implementation of the MPOWER package in Vietnam. We can report that, in term of monitoring, Vietnam is very active in the Global Tobacco Surveillance System, completing two rounds of the Global Adult Tobacco Survey (GATS) and three rounds of the Global Youth Tobacco Survey (GYTS). To protect people from tobacco smoke, Vietnam has issued and enforced a law requiring comprehensive smoking bans at workplaces and public places since 2013. Tobacco advertising and promotion are also prohibited with the exception of points of sale displays of tobacco products. Violations come in the form of promotion girls, corporate social responsibility activities from tobacco manufacturers and packages displayed by retail vendors. Vietnam is one of the 77 countries that require pictorial health warnings to be printed on cigarette packages to warn about the danger of tobacco and the warnings have been implemented effectively. Cigarette tax is 70% of factory price which is equal to less than 45% of retail price and much lower than the recommendation of WHO. However, Vietnam is one of the very few countries that require manufacturers and importers to make "compulsory contributions" at 1-2% of the factory price of cigarettes sold in Vietnam for the establishment of a Tobacco Control Fund (TCF). The TCF is being operated well. In 2015, 67 units of 63 provinces/cities, 22 ministries and political-social organizations and 6 hospitals received funding from TCF to implement a wide range of tobacco control activities. Cessation services have been starting with a a toll-free quit-line but need to be further strengthened. In conclusion, Vietnam has constantly put efforts into the tobacco control field with high commitment from the government, scientists and activists. Though several remarkable achievements have been gained, many challenges remain. To overcome those challenges, implementation strategies that take into account the contextual factors and social determinants of tobacco use in Vietnam are needed.

The Analysis and Principle Setting of High-Voltage Relaying Systems

Tran Hoang Quang Minh,Nguyen Doan Quoc Anh,Nguyen Quang Dung,Shmoilov A.V 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.11

In this paper, the analysis of the relay devices and systems performance (and another monitoring, controlling systems) to properties of the automatic power system objects is represented. The paradoxes of using a number of relaying are considered. Some events graduated from the current such as: prevention of violation of stability, liquid on of an asynchronous regime, differential guards of transformers and auto transformers are proposed and analyzed. The recommendations for operation increasing, selectivity and sensitivity of systems properties improving are given.

Travel Intention to Visit Tourism Destinations: A Perspective of Generation Z in Vietnam

NGUYEN, Viet Hoang,TRUONG, Thi Xuan Dao,PHAM, Huong Trang,TRAN, Duc Thanh,NGUYEN, Pham Hung Korea Distribution Science Association 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.2

The purpose of this research is to investigate the impacts of gen-Z's perception of consumer-generated content on social media on their travel intention with the mediating role of travel motivation push and pull. An online questionnaire survey of a total of 369 samples was conducted with the participation of gen Z in the most important cities across Vietnam. The model was analyzed using Structural Equation Modeling (SEM) using AMOS program 22 to investigate model relationships and all hypotheses are significant. The findings indicated that gen Z values the usefulness of social media and they use social media for knowledge-seeking (push factor), and this leads to their intention to visit a destination. SEM analysis also reveals that gen Z tends to use social media to find accessibility to any destinations and they are motivated highly with destinations that have clear and easy access, for example, no visa requirement or neighboring destinations. As the result, they have better intentions to visit these destinations. This research will help marketers, especially marketing specialists to gain a better understanding of gen Z, thus implement better marketing techniques to target gen Z.