EXTRACTION AND PROPERTY STUDIES OF COENZYME Q10 FROM RECOMBINANT AGROBACTERIUM TUMEFACIENS

In this report, some results of extraction and characterization of CoQ10 from recombinant A. tumefaciens are presented. Four different cell breaking methods (sonication, acidic treatment, ethanol treatment, and enzymatic lysis) in combination with the extracting steps were carried out to extract CoQ10 and the results showed that ethanol treatment was the most efficient method. Appropriate conditions for CoQ10 extraction were 25 oC, 24 hours incubation and ethanol solvent/biomass ratio of 10:1 (ml/g). Characterization of extracted CoQ10 showed that CoQ10 was sensitive to light, but stable in the temperature ranges of 4 – 60 oC and the pH range of 6.0 – 9.0. Obtained results in present study should be applied in the large scale for CoQ10 extraction, providing the CoQ10 product for testing production of functional foods

Antibacterial, antioxidant and cytotoxic activities of different fractions of acetone extract from flowers of Dipterocarpus intricatus Dyer (Dipterocarpaceae)

This study has shown for the first time the antimicrobial, antioxidant and cytotoxicity of 3 fractions of acetone extract, including hexane, chloroform and ethyl acetate from flowers of Dipterocarpus intricatus. Antibacterial test using disc diffusion method showed that the chloroform and ethyl acetate fractions inhibited the growth of all the tested bacteria, including Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, Salmonella typhimurium, Bacillus cereus and Staphylococcus aureus while the hexane fraction showed the antibacterial activity against B. cereus and S. enteritidis. Antioxidant activity and cancer cell resistance of those extracts were conducted using DPPH and MTT methods respectively. As a result, the DPPH radical scavenging activity of the hexane, chloroform and ethyl acetate fractions were determined with the IC50 values of 0.508, 0.22 and 0.075 mg/mL respectively while the cytotoxicity to HepG2 cell line of those fractions was 163.3 ppm, 106.7 ppm and 459.3 ppm. These results suggested the potential application of these fractions isolated from D. intricatus flowers as the natural antimicrobial, antioxidant and cytotoxic agents for medicine

Conamomum odorum , a new species of Zingiberaceae from central Vietnam

Conamomum odorum is described as a new species from Khanh Hoa Province, Central Vietnam. It is characterized by sweet smell, striate and narrowly elliptic leaf leaves with short petiole and ligule, ovoid congested inflorescence, pubescent calyx, cream corolla lobes, yellow, obovate and reflexed labellum with median red bands at base and hairy ovary. The new species is illustrated with detailed photographs of key characters and morphologically compared to its closest congeners C. piereanum and C. rubidum. A distribution map of the genus in Vietnam is provided.

The Virome of Acute Respiratory Diseases in Individuals at Risk of Zoonotic Infections

The ongoing coronavirus disease 2019 (COVID-19) pandemic emphasizes the need to actively study the virome of unexplained respiratory diseases. We performed viral metagenomic next-generation sequencing (mNGS) analysis of 91 nasal-throat swabs from individuals working with animals and with acute respiratory diseases. Fifteen virus RT-PCR-positive samples were included as controls, while the other 76 samples were RT-PCR negative for a wide panel of respiratory pathogens. Eukaryotic viruses detected by mNGS were then screened by PCR (using primers based on mNGS-derived contigs) in all samples to compare viral detection by mNGS versus PCR and assess the utility of mNGS in routine diagnostics. mNGS identified expected human rhinoviruses, enteroviruses, influenza A virus, coronavirus OC43, and respiratory syncytial virus (RSV) A in 13 of 15 (86.7%) positive control samples. Additionally, rotavirus, torque teno virus, human papillomavirus, human betaherpesvirus 7, cyclovirus, vientovirus, gemycircularvirus, and statovirus were identified through mNGS. Notably, complete genomes of novel cyclovirus, gemycircularvirus, and statovirus were genetically characterized. Using PCR screening, the novel cyclovirus was additionally detected in 5 and the novel gemycircularvirus in 12 of the remaining samples included for mNGS analysis. Our studies therefore provide pioneering data of the virome of acute-respiratory diseases from individuals at risk of zoonotic infections. The mNGS protocol/pipeline applied here is sensitive for the detection of a variety of viruses, including novel ones. More frequent detections of the novel viruses by PCR than by mNGS on the same samples suggests that PCR remains the most sensitive diagnostic test for viruses whose genomes are known. The detection of novel viruses expands our understanding of the respiratory virome of animal-exposed humans and warrant further studies.Peer reviewe

Community, Family, and Partner-Related Stigma Experienced by Pregnant and Postpartum Women with HIV in Ho Chi Minh City, Vietnam

Pregnant and postpartum women with HIV often face stigma and discrimination at home and in the community. In Vietnam, associations between HIV and the “social evils” of drug use and sex work contribute to stigmatization of people with HIV. We conducted a qualitative study to explore discrimination experienced by HIV-positive pregnant and postpartum women in Ho Chi Minh City at home and in the community. We conducted 20 in-depth interviews and two focus group discussions. Participants described managing disclosure of their HIV infection because of fear of stigma and discrimination, particularly to the wider community. In cases where their HIV status was disclosed, women experienced both discrimination and support. The findings highlight the need for targeted interventions to support pregnant and postpartum women with HIV, particularly during this period when they are connected to the healthcare system and more readily available for counseling

Expansion of KPC-producing Enterobacterales in four large hospitals in Hanoi, Vietnam

Objectives : The incidence of carbapenem resistance among nosocomial Gram-negative bacteria in Vietnam is high and increasing, including among Enterobacterales. In this study, we assessed the presence of one of the main carbapenemase genes, blaKPC, among carbapenem-resistant Enterobacterales (CRE) from four large hospitals in Hanoi, Vietnam, between 2010 and 2015, and described their key molecular characteristics. Methods : KPC-producing Enterobacterales were detected using conventional PCR and were further analysed using S1 nuclease pulsed-field gel electrophoresis (S1-PFGE), Southern blotting and whole-genome sequencing (WGS) for sequence typing and genetic characterisation. Results : blaKPC genes were detected in 122 (20.4%) of 599 CRE isolates. blaKPC-carrying plasmids were diverse in size. Klebsiella pneumoniae harbouring blaKPC genes belonged to ST15 and ST11, whereas KPC-producing Escherichia coli showed more diverse sequence types including ST3580, ST448, ST709 and ST405. Genotypic relationships supported the hypothesis of circulation of a population of ‘resident’ resistant bacteria in one hospital through the years and of transmission among these hospitals via patient transfer. WGS results revealed co-carriage of several other antimicrobial resistance genes and three different genetic contexts of blaKPC-2. Among these, the combination of ISEcp1–blaCTX-M and ISKpn27–blaKPC–ΔISKpn6 on the same plasmid is reported for the first time. Conclusion : We describe the dissemination of blaKPC-expressing Enterobacterales in four large hospitals in Hanoi, Vietnam, since 2010, which may have started earlier, along with their resistance patterns, sequence types, genotypic relationship, plasmid sizes and genetic context, thereby contributing to the overall picture of the antimicrobial resistance situation in Enterobacterales in Vietnam

Switchable and tunable metamaterial absorber in THz frequencies

We demonstrated a metamaterial absorber (MMA), which can be controlled by variation of conductivity or temperature. The metamaterial (MM) structure is based on three individual layers of periodic split ring resonator (SRR), a dielectric, and metallic film. The resonant frequency of the designed structure is numerically investigated at THz range of electromagnetic (EM) wave, which is explained by surface current and equivalent LC-circuit. It was found that by replacing the metallic film with VO2, the absorption intensity can be controlled by modification of the conductivity through the optical pumping power, while the absorption frequency is tuned by changing the temperature of InSb material filled into two slits of SRR. It is expected that this work will allow switchable and tunable absorption behaviours for applications of MMA

Experience of Kapandji technique in treating Colles’ fracture in central region of Vietnam

Introduction: Extra-articular fractures of the distal radius, known as Colles’ fractures, are very common. The optimal management of Colles’ fracture is still controversial. The Kapandji technique is one option for orthopedic surgeons to maintain reduced fractures, however, the effectiveness of this method is no clear consensus. This study aims to access Colles’ fracture treatment by the Kapandji technique with our experiences. Methods: This prospective study of 33 patients treated with three K-wires intra-focal fractures by the Kapandji procedure for Colles’ fractures at Hue University of Medicine and Pharmacy Hospital in Vietnam between February 2017 and May 2019. The functional outcome of the patients was assessed by the demerit score system of Gartland and Werley, and the quality of reduction was elevated on radiographic as well at 3, 6, 12, and 24 weeks postoperative. Results: 33 patients’ mean age is 54.64 ± 18.00; After 24 weeks of postoperative follow-up, 78.79% presented excellent, 21.21% good, and there are not any fair or poor cases on the functional outcome. All patients achieved complete fracture union at 12 weeks postoperative. The average immediate postoperative radial length was 9.85 mm, the radial inclination was 20.64°, and the volar tilt was 9.2°. Conclusion: The study emphasizes that the Kapandji technique in Colles’ fracture treatment is simple and possible to bring a satisfactory outcome and fast recovery