Background: Helicobacter pylori (H. pylori) strains with positive cagA gene can induce an advanced severe condition of atrophic gastritis and a higher risk of gastric carcinoma than those without cagA gene. Objective: To carry out the full sequence of cagA gene and preliminary analysis, classify cagA protein in H. pylori strains in Vietnamese patients. Subjects and method: 5 patients with H. pylori strains from Ho Chi Minh city were enrolled in the study. H. pylori was cultured and determined by PCR before sequencing full cagA gene. Analyzing cagA gene and constructing phylogenetic tree using biometrics and bioinformatics software. Results: The length of open reading frame of cagA gene of H. pylori strains in Vietnamese patients was 3480-3588 base-pairs, the number of amino acid in relavant cagA protein was 1159-1195 amino acids and all cagA protein molecules belonged to East Asian cagA, none of them was Western cagA. Even with the same classification of East Asian cagA, the Japanese H. pylori strains and Vietnamese strains were located in different cluster in phylogenetic tree. Conclusion: The study suggested that H. pylori cagA proteins in patients from Ho Chi Minh city belonged to East Asian cagA.
Helicabacter pylori ; H. pylori ; cagA

Objectives: Vibrio parahaemolyticus is a major foodborne pathogen in aquatic animals and a threat to human health worldwide. This study investigated the prevalence, antimicrobial resistance, antimicrobial resistance genes (ARGs), and biofilm formation of V. parahaemolyticus strains isolated from fish mariculture environments in Cat Ba Island, Vietnam. Methods: In total, 150 rearing water samples were collected from 10 fish mariculture farms in winter and summer. A polymerase chain reaction assay was used to identify V. parahaemolyticus, its virulence factors, and ARGs. The antimicrobial resistance patterns and biofilm formation ability of V. parahaemolyticus strains were investigated using the disk diffusion test and a microtiter plate-based crystal violet method, respectively. Results: Thirty-seven V. parahaemolyticus isolates were recovered from 150 samples. The frequencies of the tdh and trh genes among V. parahaemolyticus isolates were 8.1% and 21.6%, respectively. More than 90% of isolates were susceptible to ceftazidime, cefotaxime, and chloramphenicol, but over 72% were resistant to ampicillin, tetracycline, and erythromycin. Furthermore, 67.57% of isolates exhibited multidrug resistance. The presence of ARGs related to gentamicin (aac(3)-IV), tetracycline (tetA) and ciprofloxacin (qnrA) in V. parahaemolyticus isolates was identified. Conversely, no ARGs related to ampicillin or erythromycin resistance were detected. Biofilm formation capacity was detected in significantly more multidrug-resistant isolates (64.9%) than non-multidrug-resistant isolates (18.9%). Conclusion Mariculture environments are a potential source of antibiotic-resistant V.parahaemolyticus and a hotspot for virulence genes and ARGs diffusing to aquatic environments. Thus, the prevention of antibiotic-resistant foodborne vibriosis in aquatic animals and humans requires continuous monitoring.

In the present study, bioactivity-guided extraction and isolation of the n-hexane fraction of the fruits of Vietnamese Schisandra sphenanthera led to the isolation of five dibenzocyclooctadiene lignans as gomisin N (1), schisandrin C (2), gomisin H (3), gomisin D (4), and gomisin C (5). All the isolates were tested for their inhibition of NO production in LPS-induced RAW 264.7 cells. Among them, compounds 4 and 5 showed weak inhibition of NO production with IC 50 values of 25.0 ± 1.6 and 24.8 ± 2.0 µM, respectively. Compound 1 exhibited NO production inhibition with an IC 50 value of 15.8 ± 2.1 µM, meanwhile, schisandrin C (2) showed the most potent inhibition with an IC 50 value of 8.5 ± 0.5 µM. In addition, compound 2 had a concentrationdependent inhibitory effect on the protein expression of the inflammatory enzymes iNOS and COX-2. Their physicochemical properties and ADMET data were predicted by in silico, indicating favorable drug-like properties as well as low acute oral toxicity. The results suggest that the fruit of S. sphenanthera and its phytochemical constituents might be used as anti-inflammatory agents.

Background: The Covid-19 pandemic that occurred at the end of 2019, especially the fourth wave in Vietnam, has affected the world not only in terms of economy, society, and physical health but also affected the mental health of population in general and of medical students in particular. The use of different coping methods may be protective or risk factors for mental health problems. Objectives: 1. To investigate the prevalence of anxiety, stress, and depression among medical students during the Covid -19 pandemic 2. To describe several coping behavior among medical students during the pandemic. Subjects and methods: A descriptive cross-sectional study conducted on 2350 students of medicine programme range from the first year to the sixth year in the school year 2021 - 2022 at Hue University of Medicine and Pharmacy. Using the DASS-21 scale to survey anxiety, depression and stress in research subjects and a self-designed questionnaire to describe the coping methods of medical students. Results: out of 2350 sample, the prevelance of depression, anxiety, and stress was 38%, 33.2%, and 17% respectively. 13.8% had both anxiety and stress, 15.4% had both stress and depression, and 12.8% had a combination of anxiety, depression and stress. Coping behavior was commonly selected including: eating and sleeping regularly as usual (68.1%); doing exercise at home at least 5 days/week and 30 minutes/day (23.9%); 36.5% of students performed their favorite activities under appropriate conditions most of the time or often. In addition, 59.7% of students had learn new things on the internet, 4.5% of students had practiced meditation and relaxation, 2.9% of students had chosen to write a diary and things they were grateful for; 32% had still maintain contacted with friends via video calls, text messages and 34.4% had chosen to participate in volunteer activities. Conclusion: This study highlights a high rate of anxiety, stress and depression among medical students during the fouthth wave of the Covid-19 pandemic. Personal lifestyle changes and social activities were amongst the most comon coping behavior reported.

Aims: To isolate and characterize the lactic acid bacteria (LAB) strains from the “mam chua ca ro” (sour fermented fish) in the South of Vietnam and investigate their potential anti-bacterial properties. Methodology and results: Four LAB strains (MCR1, MCR2, MCR3 and MCR4) were isolated from the "mam chua ca ro" product and their anti-bacterial activity was determined using the spot assay and the paper disc diffusion method. The isolated LABs can inhibit Escherichia coli ATCC 25922, Staphyloccocus aureus ATCC 25923 and Vibrio parahaemolyticus BV016 and produce bacteriocin to control the growth of E. coli ATCC 25922 and S. aureus ATCC 25923, except V. parahaemolyticus. MCR2 was chosen to sequence 16S rRNA of Pediococcus acidilactic. Conclusion, significance and impact of study On the basis of their prominent anti-pathogenic bacteria activity, LAB strains isolated from Vietnamese sour-fermented fish products were verified as prospective probiotics.
Lactobacillales--isolation & ; purification ; Pediococcus acidilactici

As authorities braced for the arrival of the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infrastructure investments and government directives prompted action in central Viet Nam to establish capacity for genomic surveillance sequencing. From 17 November 2021 to 7 January 2022, the Pasteur Institute in Nha Trang sequenced 162 specimens from 98 150 confirmed SARS-CoV-2 cases in the region collected from 8 November to 31 December 2021. Of these, all 127 domestic cases were identified as the B.1.617.2 (Delta) variant, whereas 92% (32/35) of imported cases were identified as the B.1.1.529 (Omicron) variant, all among international flight passengers. Patients were successfully isolated, enabling health-care workers to prepare for additional cases. Most (78%) of the 32 Omicron cases were fully vaccinated, suggesting continued importance of public health and social measures to control the spread of new variants.