Some characters of bacterial cellulases in goats' rumen elucidated by metagenomic DNA analysis and the role of fibronectin 3 module for endoglucanase function

Nguyen, Khanh Hoang Viet,Dao, Trong Khoa,Nguyen, Hong Duong,Nguyen, Khanh Hai,Nguyen, Thi Quy,Nguyen, Thuy Tien,Nguyen, Thi Mai Phuong,Truong, Nam Hai,Do, Thi Huyen Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.5

Objective: Fibronectin 3 (FN3) and immunoglobulin like modules (Ig) are usually collocated beside modular cellulase catalytic domains. However, very few researches have investigated the role of these modules. In a previous study, we have sequenced and analyzed bacterial metagenomic DNA in Vietnamese goats' rumen and found that cellulase-producing bacteria and cellulase families were dominant. In this study, the properties of modular cellulases and the role of a FN3 in unique endoglucanase belonging to glycosyl hydorlase (GH) family 5 were determined. Methods: Based on Pfam analysis, the cellulases sequences containing FN3, Ig modules were extracted from 297 complete open reading frames (ORFs). The alkaline, thermostability, tertiary structure of deduced enzymes were predicted by AcalPred, TBI software, Phyre2 and Swiss models. Then, whole and truncated forms of a selected gene were expressed in Escherichia coli and purified by His-tag affinity column for assessment of FN3 ability to enhance enzyme activity, solubility and conformation. Results: From 297 complete ORFs coding for cellulases, 148 sequences containing FN3, Ig were identified. Mostly FN3 appeared in 90.9% beta-glucosidases belonging to glycosyl hydrolase family 3 (GH3) and situated downstream of catalytic domains. The Ig was found upstream of 100% endoglucanase GH9. Rarely FN3 was seen to be situated downstream of X domain and upstream of catalytic domain endoglucanase GH5. Whole enzyme (called XFN3GH5 based on modular structure) and truncate forms FN3, XFN3, FN3GH5, GH5 were cloned in pET22b (+) and pET22SUMO to be expressed in single and fusion forms with a small ubiquitin-related modifier partner (S). The FN3, SFN3 increased GH5 solubility in FN3GH5, SFN3GH5. The SFN3 partly served for GH5 conformation in SFN3GH5, increased modules interaction and enzyme-soluble substrate affinity to enhance SXFN3GH5, SFN3GH5 activities in mixtures. Both SFN3 and SXFN3 did not anchor enzyme on filter paper but exfoliate and separate cellulose chains on filter paper for enzyme hydrolysis. Conclusion: Based on these findings, the presence of FN3 module in certain cellulases was confirmed and it assisted for enzyme conformation and activity in both soluble and insoluble substrate.

Parenchymal-sparing anatomical hepatectomy based on portal ramification of the right anterior section: A prospective multicenter experience with short-term outcomes

Truong Giang Nguyen,Thanh Khiem Nguyen,Ham Hoi Nguyen,Hong Son Trinh,Tuan Hiep Luong,Minh Trong Nguyen,Van Duy Le,Hai Dang Do,Kieu Hung Nguyen,Van Minh Do,Quang Huy Tran,Cuong Thinh Nguyen 한국간담췌외과학회 2024 Annals of hepato-biliary-pancreatic surgery Vol.28 No.1

Backgrounds/Aims: Parenchymal-sparing anatomical hepatectomy (Ps–AH) based on portal ramification of the right anterior section (RAS) is a new technique to avoid unnecessarily transecting too much liver parenchyma, especially in cases of major anatomical hepatectomy. Methods: We prospectively assessed 26 patients with primary hepatic malignancies having undergone major Ps–AH based on portal ramification of the RAS from August 2018 to August 2022 (48 months). The perioperative indications, clinical data, intra-operative index, pathological postoperative specimens, postoperative complications, and follow-up results were retrospectively evaluated. Results: Among the 26 patients analyzed, there was just one case that had intrahepatic cholangiocarcinoma The preoperative level of α– Fetoprotein was 25.2 ng/mL. All cases (100%) had Child–Pugh A liver function preoperatively. The ventral/dorsal RAS was preserved in 19 and 7 patients, respectively. The mean surgical margin was 6.2 mm. The mean surgical time was 228.5 minutes, while the mean blood loss was 255 mL. In pathology, 5 cases (19.2%) had microvascular invasion, and in the group of HCC patients, 92% of all cases had moderate or poor tumor differentiation. Six cases (23.1%) of postoperative complications were graded over III according to the Clavien–Dindo system, including in three patients resistant ascites or intra-abdominal abscess that required intervention. Conclusions: Parenchymal-sparing anatomical hepatectomy based on portal ramification of the RAS to achieve R0-resection was safe and effective, with favorable short-term outcomes. This technique can be used widely in clinical practice.

Synthesis and Analysis of Nanocrystalline β1-Cu3Al and β2-NiAl Intermetallic- Reinforced Aluminum Matrix Composite by High Energy Ball Milling

Hong-Hai Nguyen,Minh-Thuyet Nguyen,김원주,김진천 대한금속·재료학회 2017 METALS AND MATERIALS International Vol.23 No.1

Nanocrystalline β1-Cu3Al and β2-NiAl intermetallic compounds were in-situ reinforced in the aluminum matrix with the atomic composition of Al67Cu20Ni13 by the mechanical alloying of elemental powders. Both β1-Cu3Al, β2-NiAl phases that can be only co-synthesized in Cu base alloys have been obtained after 15h milling in this study. The phase evolution during milling process was investigated by X-ray diffraction. The β1-Cu3Al, β2-NiAl phases were metastable with further milling time up to 40 h. Specially, unreacted Al matrix has been totally transformed to amorphous state in the final powder. A remarkable crystalline size of 6.5 nm was reached after 15 h milling time. Thermal stability of the milled powder was also studied by differential thermal analysis. It is shown that β1-Cu3Al, β2-NiAl phases were stable up to higher than 550 °C. Moreover, the inter-diffusion between Al matrix and Cu3Al within the temperature range of 620-740 °C led to the formation of superstructure ζ1-Al3Cu4 phase.

Development of a SCAR Marker Linked to Bacterial Wilt (Ralstonia solanacearum) Resistance in Tomato Line Hawaii 7996 Using Bulked-Segregant Analysis

Hai Thi Hong Truong,김수연,Hung Ngoc Tran,Thuy Thi Thu Nguyen,Long Tien Nguyen,Toan Kim Hoang 한국원예학회 2015 Horticulture, Environment, and Biotechnology Vol.56 No.4

We report the development of a codominant sequence characterized amplified region (SCAR) marker linked to resistance to a Korean R. solanacearum isolate in tomato line Hawaii 7996. Bulked segregant analysis was employed for rapid identification of RAPD markers linked to resistance genes. Genomic DNA from six resistant F9 recombinant inbred lines (RILs) and six susceptible F9 RILs, which derived from a cross between S. lycopersicum Hawaii 7996 (resistant parent) and S. pimpinellifolium WVa 700 (susceptible parent) were pooled in to an R-pool and an S-pool, respectively. A total of 800 RAPD primers were screened and only six primers (UBC#176, 205, 287, 317, 350, and 676) showed polymorphism between R- and S- pools. Of these, only two markers UBC#176 and 317 revealed a 100% linkage in the individual plants comprising the contrasting bulks. Of these, the marker UBC#176 was converted into a co-dominant SCAR marker and designated as SCU176-534. The marker SCU176-534 was confirmed by genotyping the individual of the R- and S- pools and gave the same result as UBC#176. When the marker SCU176-534 was further validated for association with resistance and its potential for maker-assisted selection (MAS) in 92 tomato lines and cultivars, the results showed that none of these carries the resistance gene. Thus, SCAR marker SCU176-534 can be used in early selection of resistant lines when Hawaii 7996 is used as a parent in a breeding program.

The Factors Affecting Intention to Use Smarthome Devices in Vietnam

Nguyen Thi-Hong-Linh,Duong Minh-Hung,Nguyen Hai-Dang,Vo Dang-HongNgan,Vu Duy-Phuong-Trinh,Le Hoanh-Su 한국경영정보학회 2018 한국경영정보학회 학술대회논문집 Vol.2018 No.5

Synthesis of Carbonyl Iron-reinforced Polystyrene by High Energy Ball Milling

Nguyen, Hong-Hai,Nguyen, Minh-Thuyet,Kim, Won Joo,Kim, Jin-Chun,Kim, Young-Soo,Kim, Young-Hyuk,Nazarenko, Olga B. The Korean Powder Metallurgy Institute 2016 한국분말재료학회지 (KPMI) Vol.23 No.4

Carbonyl iron (CI) is successfully incorporated as an additive into a polystyrene (PS) matrix via a highenergy ball milling method, under an n-hexane medium with volume fractions between 1% and 5% for electromagnetic interference shielding applications by the combination of magnetic CI and an insulating PS matrix. The morphology and the dispersion of CI are investigated by field emission scanning electron microscopy, which indicates a uniform distribution of CI in the PS matrix after 2 h of milling. The thermal behavior results indicate no significant degradation of the PS when there is a slight increase in the onset temperature with the addition of CI powder, when compared to the as-received PS pellet. After milling, there are no interactions between the CI and the PS matrix, as confirmed by Fourier transformed infrared spectroscopy. In this study, the milled CI-PS powder is extruded to make filaments, and can have potential applications in the 3-D printing industry.

Key Determinants for Users Intention to Use Smarthome Devices in Vietnam

Nguyen, Thi-Hong-Linh,Duong, Minh-Hung,Nguyen, Hai-Dang,Vo, Dang-HongNgan,Vu, Duy-Phuong-Trinh,Le, Hoanh-Su Korea Multimedia Society 2018 The journal of multimedia information system Vol.5 No.4

Smarthome is one of the remarkable fields of the industrial revolution 4.0, which are popular in many countries such USA, EURO, Japan and Korea. However, how Vietnamese people are considering and having intension to use smarthome devices is still a question for marketers and researchers. This study develops a comprehensive research model that can explain potential customers' behavioral intentions to adopt and use Smarthome services in Viet Nam and figure which key factors affect the intention. This study proposes and validates a new theoretical model that extends the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2). The model consists of eight factors that affect one element (Behavioral Intention), specifically: Habits, Perceived usefulness, Perceived ease of use, Trust, Innovativeness Personal, Perceived value, Hedonic motivations and Social influences. Data were collected from 304 Vietnamese citizens by sending the email to survey questionnaire, direct contact with the experienced smarthome users. Through regression analysis, data from samples were analysed with SPSS 20 software and verification of hypotheses, the results show the key determinants affecting the intention to use smarthome appliances in Vietnam: Perceived Value, Social Influence, Perceived Usefulness, Perceived Ease of Use and Trust. From this result, several recommendations have been suggested to to smarthome devices vendors and marketer to improve products as well as marketing approaches to meet customer needs.

Grassroots Democracy and Inequality Reduction in Rural Vietnam: The Case of Thái Bình in 1997 and Now

Hai Hong Nguyen 서울대학교행정대학원 2014 Asian Journal of Political Science Vol.22 No.1

The Communist Party of Vietnam (CPV) adopted grassroots democracy as a political tool to reduce inequality which was a causal factor prompting farmer protests in Thái Bình in 1997. At the international level, the nexus between democracy and inequality has attracted extensive scholarly research over the last two decades. By revisiting the case of Thái Bình, on the one hand, the article attempts to assess the impact of grassroots democracy after 15 years on inequality reduction thereat, and on the other, to contribute to the general discourse on the nexus between these two concepts. The article is organized in two major parts: the first being the literature review and theoretical framing, and the second, findings presentation. It concludes that grassroots democracy has contributed to inequality reduction in rural Vietnam, but is far more likely to meet the demand to avoid a challenge for the CPV again due to the inequality that remains.

A Laboratory-Scale Study of the Applicability of a Halophilic Sediment Bioelectrochemical System for in situ Reclamation of Water and Sediment in Brackish Aquaculture Ponds: Establishment, Bacterial Community and Performance Evaluation

( Hai The Pham ),( Hien Thi Tran ),( Linh Thuy Vu ),( Hien The Dang ),( Thuy Thu Thi Nguyen ),( Thu Ha Thi Dang ),( Mai Thanh Thi Nguyen ),( Huy Quang Nguyen ),( Byung Hong Kim ) 한국미생물·생명공학회 2019 Journal of microbiology and biotechnology Vol.29 No.7

In this study, we investigated the potential of using sediment bioelectrochemical systems (SBESs) for in situ treatment of the water and sediment in brackish aquaculture ponds polluted with uneaten feed. An SBES integrated into a laboratory-scale tank simulating a brackish aquaculture pond was established. This test tank and the control (not containing the SBES) were fed with shrimp feed in a scheme that mimics a situation where 50% of feed is uneaten. After the SBES was inoculated with microbial sources from actual shrimp pond sediments, electricity generation was well observed from the first experimental week, indicating successful enrichment of electrochemically active bacteria in the test tank sediment. The electricity generation became steady after 3 weeks of operation, with an average current density of 2.3 mA/㎡ anode surface and an average power density of 0.05 mW/㎡ anode surface. The SBES removed 20-30% more COD of the tank water, compared to the control. After 1 year, the SBES also reduced the amount of sediment in the tank by 40% and thus could remove approximately 40% more COD and approximately 52% more nitrogen from the sediment, compared to the control. Insignificant amounts of nitrite and nitrate were detected, suggesting complete removal of nitrogen by the system. PCR-DGGE-based analyses revealed the dominant presence of Methylophilus rhizosphaerae, Desulfatitalea tepidiphila and Thiothrix eikelboomii, which have not been found in bioelectrochemical systems before, in the bacterial community in the sediment of the SBES-containing tank. The results of this research demonstrate the potential application of SBESs in helping to reduce water pollution threats, fish and shrimp disease risks, and thus farmers’ losses.

Sulfate Reduction for Bioremediation of AMD Facilitated by an Indigenous Acidand Metal-Tolerant Sulfate-Reducer

( Hai Thi Nguyen ),( Huong Lan Nguyen ),( Minh Hong Nguyen ),( Thao Kim Nu Nguyen ),( Hang Thuy Dinh ) 한국미생물 · 생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.7

Acid mine drainage (AMD) has been a serious environmental issue that threatens soil and aquatic ecosystems. In this study, an acid-tolerant sulfate-reducing bacterium, strain S4, was isolated from the mud of an AMD storage pond in Vietnam via enrichment in anoxic mineral medium at pH 5. Comparative analyses of sequences of the 16S rRNA gene and dsrB gene involved in sulfate reduction revealed that the isolate belonged to the genus Desulfovibrio, and is most closely related to Desulfovibrio oxamicus (with 99% homology in 16S rDNA sequence and 98% homology in dsrB gene sequence). Denaturing gradient gel electrophoresis (DGGE) analyses of dsrB gene showed that strain S4 represented one of the two most abundant groups developed in the enrichment culture. Notably, strain S4 was capable of reducing sulfate in low pH environments (from 2 and above), and resistance to extremely high concentration of heavy metals (Fe 3,000 mg/l, Zn 100 mg/l, Cu 100 mg/ l). In a batch incubation experiment in synthetic AMD with pH 3.5, strain S4 showed strong effects in facilitating growth of a neutrophilic, metal sensitive Desulfovibrio sp. strain SR4H, which was not capable of growing alone in such an environment. Thus, it is postulated that under extreme conditions such as an AMD environment, acid- and metal-tolerant sulfate-reducing bacteria (SRB)- like strain S4 would facilitate the growth of other widely distributed SRB by starting to reduce sulfate at low pH, thus increasing pH and lowering the metal concentration in the environment. Owing to such unique physiological characteristics, strain S4 shows great potential for application in sustainable remediation of AMD.