1.NO Production Inhibition of Lignans from Vietnamese Schisandra sphenanthera Rehd. et Wils. Fruits
Hong Khuyen THI PHAM ; Phu Chi Hieu TRUONG ; Khanh Huyen THI PHAM ; Dao Cuong TO ; Manh Hung TRAN ; Tu Nguyen THI THANH
Natural Product Sciences 2023;29(4):312-322
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.
2.Management of Antibiotic-Resistant Helicobacter pylori Infection: Perspectives from Vietnam
Vu VAN KHIEN ; Duong Minh THANG ; Tran Manh HAI ; Nguyen Quang DUAT ; Pham Hong KHANH ; Dang Thuy HA ; Tran Thanh BINH ; Ho Dang Quy DUNG ; Tran Thi Huyen TRANG ; Yoshio YAMAOKA
Gut and Liver 2019;13(5):483-497
Antibiotic resistance is the most important factor leading to the failure of eradication regimens. This review focuses on the prevalence of Helicobacter pylori primary and secondary resistance to clarithromycin, metronidazole, amoxicillin, levofloxacin, tetracycline, and multidrug in Vietnam. We searched the PubMed, EMBASE, Vietnamese National Knowledge Infrastructure, and Vietnamese Biomedical databases from January 2000 to December 2016. The search terms included the following: H. pylori infection, antibiotic (including clarithromycin, metronidazole, amoxicillin, levofloxacin, tetracycline, and multidrug) resistance in Vietnam. The data were summarized in an extraction table and analyzed manually. Finally, Excel 2007 software was used to create charts. Ten studies (three studies in English and seven in Vietnamese) were included in this review. A total of 308, 412, 523, 408, 399, and 268 H. pylori strains were included in this review to evaluate the prevalence of H. pylori primary resistance to amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and multidrug resistance, respectively. Overall, the primary resistance rates of amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and multidrug resistance were 15.0%, 34.1%, 69.4%, 27.9%, 17.9% and 48.8%, respectively. Secondary resistance rates of amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and multidrug resistance were 9.5%, 74.9%, 61.5%, 45.7%, 23.5% and 62.3%, respectively. In Vietnam, primary and secondary resistance to H. pylori is increasing over time and affects the effectiveness of H. pylori eradication.
Amoxicillin
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Asian Continental Ancestry Group
;
Bismuth
;
Clarithromycin
;
Drug Resistance, Microbial
;
Drug Resistance, Multiple
;
Helicobacter pylori
;
Helicobacter
;
Humans
;
Levofloxacin
;
Metronidazole
;
Prevalence
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Tetracycline
;
Vietnam
3.Within-household SARS-CoV-2 transmission and vaccine effectiveness in the first three COVID-19 school outbreaks in northern Viet Nam, September–December 2021
Trang Thu Vu ; Tu Huy Ngo ; Khanh Cong Nguyen ; Vu Thi Lan ; Cu Thi Bich Hanh ; Le Hong Son ; Huyen Thi Nguyen ; Hien Thi Nguyen ; Nghia Duy Ngu ; Duong Nhu Tran ; Duc-Anh Dang ; Florian Vogt ; Thai Quang Pham
Western Pacific Surveillance and Response 2024;15(3):19-30
Objective: The risk of transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from schoolchildren to their household and the protective effects of vaccination in these settings remain poorly understood. We assessed the transmission dynamics of schoolchildren with SARS-CoV-2 within their households and the protective effects of coronavirus disease (COVID-19) vaccination among household members in Viet Nam.
Methods: We estimated the attack rate, vaccine effectiveness and adjusted risk ratio (aRR) of factors associated with SARS-CoV-2 transmission to household contacts of children confirmed to have COVID-19 who attended three schools in Ha Nam, Phu Tho and Thanh Hoa provinces between September and December 2021 using multivariable regression with household-level random effects.
Results: This retrospective cohort study included 157 children infected with SARS-CoV-2 and their 540 household contacts. The attack rate among household contacts was 24.6% (133/540). Overall, vaccine effectiveness among household contacts was 39% (95% confidence interval [CI]: -1 to -63), higher among males than females and higher in adults aged >40 years. COVID-19 transmission was greater among female household contacts compared with males (aRR: 1.35, 95% CI: 0.94 to 1.95), although not statistically significant, and highest among those aged 19–39 years (aRR: 2.51, 95% CI: 1.50 to 4.21). Fully vaccinated household contacts had significantly lower infection risk (aRR: 0.46, 95% CI: 0.26 to 0.84).
Discussion: We found substantial onward transmission of SARS-CoV-2 from schoolchildren to household members, and older people were more likely to be protected by vaccination. We recommend that schoolchildren and all household members living with schoolchildren receive at least two doses of a COVID-19 vaccine. Recognizing the role of schoolchildren in the onward transmission of COVID-19 is an important lesson learned by Viet Nam that can help not only in managing other outbreaks but also in protecting schoolchildren by predicting the progress of the outbreak and preparing for a timely response.