Effects of Compounds from Physalis angulata on Fatty Acid Synthesis and Glucose Metabolism in HepG2 Cells via the AMP-activated Protein Kinase Pathway

Hoang Thai Hoa,Nguyen Thi Thu,Nguyen Thuong Dong,Tran Thi Oanh,Tran Thi Hien,Do Thi Ha 한국생약학회 2020 Natural Product Sciences Vol.26 No.3

The ability of the total extract from Physalis angulata; three fractions after partitioning with n-hexane, ethyl acetate (TBE), and water; and four withanolides (compounds 1 – 4) to phosphorylate 5'-adenosine monophosphate-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in HepG2 cells was evaluated. The TBE fraction (50 μg/mL) activated p-ACC and p-AMPK expression most strongly. Compounds 1 – 4 (10 μM) upregulated p-ACC expression at different levels. Compound 4 induced the most significant changes in p-AMPK expression, followed by 1 and 2. Sterol regulatory element-binding proteins (SREBPs) play a functional role in the transcriptional regulation of the lipogenic pathway, including fatty acid synthase (FAS) and ACC. The effects of compounds 2 and 4 (10 μM) on FAS and SREBP-1c expression under high glucose conditions (30 mM) in HepG2 cells were evaluated further. Both dose-dependently inhibited FAS and SREBP-1c expression as well as lipid accumulation (1 – 10 μM) were compared to high-concentration glucose control, which upregulated FAS and SREBP-1c. These results suggest that compounds 2 and 4 upregulate AMPK, suppress FAS and SREBP-1c, and have potential effects on glucose and lipid metabolism.

First Report on Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus Isolates in Children Admitted to Tertiary Hospitals in Vietnam

( Nguyen Thai Son ),( Vu Thi Thu Huong ),( Vu Thi Kim Lien ),( Do Thi Quynh Nga ),( Tran Thi Hai Au ),( Tang Thi Nga ),( Le Nguyen Minh Hoa ),( Tran Quang Binh ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.9

The extensive distribution of multidrug-resistant (MDR) methicillin-resistant Staphylococcus aureus (MRSA) poses a threat to healthcare worldwide. This study aimed to investigate the MDR and molecular patterns of MRSA isolates in children admitted to the two biggest tertiary care pediatric hospitals in northern and southern Vietnam. A total of 168 MRSA strains were collected to determine antibiotic susceptibility by minimum inhibitory concentration tests. Antibiotic-resistant genes, pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec (SCCmec) typing, and multilocus sequence typing were used for the molecular characterization of MRSA. Among the total strains, the MDR rate (51.8%) was significantly higher in the northern hospital than in the southern hospital (73% vs. 39%, p < 0.0001). The MDR-MRSA with the highest rates were “ciprofloxacin-erythromycin-gentamicin-tetracyclines” (35.6%), followed by “erythromycin-tetracycline-chloramphenicol” (24.1%), and “ciprofloxacin-erythromycin-gentamicin” (19.5%), showing an accumulative total of 79.3%. The most susceptible antibiotics were rifampicin (100%) and vancomycin (100%), followed by doxycycline (94.0%), meropenem (78.0%), and cefotaxime (75.0%). The SCCmecII strains showed greater resistance to gentamicin, ciprofloxacin, tetracycline, meropenem and cephalosporins compared with the other strains. The SCCmecII strains exhibited the highest rate in the tested genes (aacA/aphD: 55.2%, ermA/B/C: 89.7%, and tetK/M: 82.8%). ST5-SCCmecII was the predominant clone in the northern hospital, whereas SCCmecIVa was more pronounced in the southern hospital. In conclusion, our results raised concerns about the predominant MDR-MRSA strains in the pediatric hospitals in Vietnam. The north-south difference in the antibiotic resistance patterns and genetic structure of MRSA suggests different MRSA origins and various uses of antimicrobial agents between the two regions.

Enhanced electrosorption of NaCl and nickel(II) in capacitive deionization by CO2 activation coconut-shell activated carbon

Huynh Le Thanh Nguyen,Tran Thanh Nhut,Ho Thi Thanh Nguyen,Le Xuan Hoa,Le Viet Hai,Nguyen Thai Hoang 한국탄소학회 2022 Carbon Letters Vol.32 No.6

Enhancing the capacitive deionization performance requires the inner structure expansion of porous activated carbon to facilitate the charge storage and electrolyte penetration. This work aimed to modify the porosity of coconut-shell activated carbon (AC) through CO2 activation at high temperature. The electrochemical performance of CO2-activated AC electrodes was evaluated by cyclic voltammetry, charge/discharge test and electrochemical impedance spectroscopy, which exhibited that AC-800 had the superior performance with the highest capacitance of 112 F/g at the rate of 0.1 A/g and could operate for up to 4000 cycles. Furthermore, in the capacitive deionization, AC-800 showed salt removal of 9.15 mg/g with a high absorption rate of 2.8 mg/g min and Ni(II) removal of 5.32 mg/g with a rate close to 1 mg/g.min. The results promote the potential application of CO2-activated AC for desalination as well as Ni-removal through capacitance deionization (CDI) technology.

Gas sensor based on nanoporous hematite nanoparticles: Effect of synthesis pathways on morphology and gas sensing properties

Nguyen Duc Cuong,Tran Thai Hoa,Dinh Quang Khieu,Nguyen Duc Hoa,Nguyen Van Hieu 한국물리학회 2012 Current Applied Physics Vol.12 No.5

The development of a low cost and scalable gas sensor for the detection of toxic and flammable gases with fast response and high sensitivity is extremely important for monitoring environmental pollution. In this work, we introduce two different synthesis pathways for the preparation of scalable Fe2O3nanoparticles for gas sensor applications. One is co-precipitation and the other is hydrothermal method. The gas sensing properties of the a-Fe2O3 nanoparticles (NPs) fabricated by different synthesis pathways were studied and compared. The performance of the NPs in the detection of toxic and flammable gases such as carbon dioxide, ammonia, liquefied petroleum gas, ethanol, and hydrogen was evaluated. The Fe2O3 NP-based gas sensors exhibited high sensitivity and a response time of less than a minute to analytic gases. However, the NPs fabricated by the one-step direct method exhibited higher sensitivities than those generated by the a-Fe2O3 NPs obtained by co-precipitation synthesis possibly because of their nanoporous structure. This performance is attributed to the large specific surface area of the NPs, which results in higher sensitivity. The development of a low cost and scalable gas sensor for the detection of toxic and flammable gases with fast response and high sensitivity is extremely important for monitoring environmental pollution. In this work, we introduce two different synthesis pathways for the preparation of scalable Fe2O3nanoparticles for gas sensor applications. One is co-precipitation and the other is hydrothermal method. The gas sensing properties of the a-Fe2O3 nanoparticles (NPs) fabricated by different synthesis pathways were studied and compared. The performance of the NPs in the detection of toxic and flammable gases such as carbon dioxide, ammonia, liquefied petroleum gas, ethanol, and hydrogen was evaluated. The Fe2O3 NP-based gas sensors exhibited high sensitivity and a response time of less than a minute to analytic gases. However, the NPs fabricated by the one-step direct method exhibited higher sensitivities than those generated by the a-Fe2O3 NPs obtained by co-precipitation synthesis possibly because of their nanoporous structure. This performance is attributed to the large specific surface area of the NPs, which results in higher sensitivity.

Facile synthesis of multifunctional Ag/Fe3O4-CS nanocomposites for antibacterial and hyperthermic applications

Ngoan Thi Nguyen,Dai Lam Tran,Duc Cuong Nguyen,Thai Loc Nguyen,Thi Cham Ba,Binh Hai Nguyen,Thi Duong Ba,Nam Hong Pham,Dzung Tuan Nguyen,Thai Hoa Tran,Gia Dien Pham 한국물리학회 2015 Current Applied Physics Vol.15 No.11

Nanocomposites containing two or more functional constituents are attractive candidates for advanced nanomaterials. In this study, multifunctional Ag/Fe3O4-CS nanocomposites were successfully prepared, using chitosan as a stabilizing and cross-linking agent. The as-synthesized nanocomposites were characterized by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), UVevisible spectrophotometer (UVeVis) and vibrating sample magnetometer (VSM). The results demonstrated that Ag/Fe3O4-CS composite nanoparticles (NPs) were composed of parent components, Fe3O4 and Ag NPs, which were uniformly dispersed in the chitosan matrix. The hybrid NPs exhibited strong antibacterial property against Pseudomonas aeruginosa. With high magnetization value (67 emu/g), the synthesized Ag/Fe3O4-CS composite can be easily separated or recycled in potential biomedical applications. Furthermore, the results showed that the multicomponent hybrid nanostructures appeared to be the promising material for local hyperthermia, which can be used as thermoseeds for localized hyperthermia treatment of cancers.