The RET gene point mutation is the main molecular alteration involved in medullary thyroid carcinoma (MTC) tumorigenesis. Previous studies in Vietnam mainly consisted of case reports, with limited data on larger sample sizes. In this study, we investigated RET gene mutations in exons 10, 11, and 16 and analyzed clinicopathological features of a series of Vietnamese MTC patients. Methods: We collected 33 tissue samples from patients with MTC and analyzed RET mutations using the Sanger sequencing method. The relationship between hotspot RET mutations (exons 10, 11, 16) and clinicopathological features were investigated. Results: Among the 33 analyzed cases, 17 tumors (52%) harbored RET mutations in exon 10, 11, or 16. A total of 10 distinct genetic alterations were identified, including eight missense mutations and two short indels. Of these, seven were classified as pathogenic mutations based on previous publications, with p.M918T being the most frequent (4 cases), followed by p.C634R (3 cases) and p.C618R (3 cases). Mutations were significantly associated with specific histological patterns, such as the nested/insular pattern (p=.026), giant cells (p=.007), nuclear pleomorphism (p=.018), stippled chromatin (p=.044), and amyloid deposits (p=.024). No mutations were found in germline analyses, suggesting these were somatic alterations. Conclusions: Our results provided the first comprehensive analysis of RET mutations in Vietnamese MTC patients. The most frequent mutation was p.M918T, followed by p.C634R and p.C618R. Mutations in these three exons were linked to specific histopathological features. Information on mutational profiles of patients with MTC will further aid in the development of targeted therapeutics to ensure effective disease management.

The RET gene point mutation is the main molecular alteration involved in medullary thyroid carcinoma (MTC) tumorigenesis. Previous studies in Vietnam mainly consisted of case reports, with limited data on larger sample sizes. In this study, we investigated RET gene mutations in exons 10, 11, and 16 and analyzed clinicopathological features of a series of Vietnamese MTC patients. Methods: We collected 33 tissue samples from patients with MTC and analyzed RET mutations using the Sanger sequencing method. The relationship between hotspot RET mutations (exons 10, 11, 16) and clinicopathological features were investigated. Results: Among the 33 analyzed cases, 17 tumors (52%) harbored RET mutations in exon 10, 11, or 16. A total of 10 distinct genetic alterations were identified, including eight missense mutations and two short indels. Of these, seven were classified as pathogenic mutations based on previous publications, with p.M918T being the most frequent (4 cases), followed by p.C634R (3 cases) and p.C618R (3 cases). Mutations were significantly associated with specific histological patterns, such as the nested/insular pattern (p=.026), giant cells (p=.007), nuclear pleomorphism (p=.018), stippled chromatin (p=.044), and amyloid deposits (p=.024). No mutations were found in germline analyses, suggesting these were somatic alterations. Conclusions: Our results provided the first comprehensive analysis of RET mutations in Vietnamese MTC patients. The most frequent mutation was p.M918T, followed by p.C634R and p.C618R. Mutations in these three exons were linked to specific histopathological features. Information on mutational profiles of patients with MTC will further aid in the development of targeted therapeutics to ensure effective disease management.

The RET gene point mutation is the main molecular alteration involved in medullary thyroid carcinoma (MTC) tumorigenesis. Previous studies in Vietnam mainly consisted of case reports, with limited data on larger sample sizes. In this study, we investigated RET gene mutations in exons 10, 11, and 16 and analyzed clinicopathological features of a series of Vietnamese MTC patients. Methods: We collected 33 tissue samples from patients with MTC and analyzed RET mutations using the Sanger sequencing method. The relationship between hotspot RET mutations (exons 10, 11, 16) and clinicopathological features were investigated. Results: Among the 33 analyzed cases, 17 tumors (52%) harbored RET mutations in exon 10, 11, or 16. A total of 10 distinct genetic alterations were identified, including eight missense mutations and two short indels. Of these, seven were classified as pathogenic mutations based on previous publications, with p.M918T being the most frequent (4 cases), followed by p.C634R (3 cases) and p.C618R (3 cases). Mutations were significantly associated with specific histological patterns, such as the nested/insular pattern (p=.026), giant cells (p=.007), nuclear pleomorphism (p=.018), stippled chromatin (p=.044), and amyloid deposits (p=.024). No mutations were found in germline analyses, suggesting these were somatic alterations. Conclusions: Our results provided the first comprehensive analysis of RET mutations in Vietnamese MTC patients. The most frequent mutation was p.M918T, followed by p.C634R and p.C618R. Mutations in these three exons were linked to specific histopathological features. Information on mutational profiles of patients with MTC will further aid in the development of targeted therapeutics to ensure effective disease management.

Aims: The objective of the study was to isolate bacteriophages and conduct a comprehensive analysis of their potential against Xanthomonas oryzae pv. oryzae (Xoo) strains in the Mekong Delta, Vietnam. Methodology and results: Twelve Xoo strains were isolated from rice fields located in the Mekong Delta, Vietnam. Among these strains, three strains Xoo L019, L020 and L024, showed the highest disease index of bacterial blight. Four phages specific to Xoo were isolated from soil, water and leaf samples, and their morphologies were determined. In a test against 12 Xoo strains, phage L541, MLA23 or W41 could infect 10 of the 12 Xoo strains, while phage LBH01 could infect 8 of the 12 Xoo strains. The stability of the phages to pH, organic solvents, UV-A and UV-B was also evaluated. Conclusion, significance and impact of study The initial characterization of the phages indicates their potential as biocontrol agents against bacterial blight in rice. The study is one of the very first studies about Xoo phages in rice in Vietnam.

Objective: In Viet Nam, tuberculosis (TB) prevalence surveys revealed that approximately 98% of individuals with pulmonary TB have TB-presumptive abnormalities on chest radiographs, while 32% have no TB symptoms. This prompted the adoption of the “Double X” strategy, which combines chest radiographs and computer-aided detection with GeneXpert testing to screen for and diagnose TB among vulnerable populations. The aim of this study was to describe demographic, clinical and radiographic characteristics of symptomatic and asymptomatic Double X participants and to assess multilabel radiographic abnormalities on chest radiographs, interpreted by computer-aided detection software, as a possible tool for detecting TB-presumptive abnormalities, particularly for subclinical TB. Methods: Double X participants with TB-presumptive chest radiographs and/or TB symptoms and known risks were referred for confirmatory GeneXpert testing. The demographic and clinical characteristics of all Double X participants and the subset with confirmed TB were summarized. Univariate and multivariable logistic regression modelling was used to evaluate associations between participant characteristics and subclinical TB and between computer-aided detection multilabel radiographic abnormalities and TB. Results: From 2020 to 2022, 96 631 participants received chest radiographs, with 67 881 (70.2%) reporting no TB symptoms. Among 1144 individuals with Xpert-confirmed TB, 51.0% were subclinical. Subclinical TB prevalence was higher in older age groups, non-smokers, those previously treated for TB and the northern region. Among 11 computer-aided detection multilabel radiographic abnormalities, fibrosis was associated with higher odds of subclinical TB. Discussion: In Viet Nam, Double X community case finding detected pulmonary TB, including subclinical TB. Computer-aided detection software may have the potential to identify subclinical TB on chest radiographs by classifying multilabel radiographic abnormalities, but further research is needed.

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.

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).

A new crinane-type alkaloid, 6-epihydroxypowelline (1), together with six known alkaloids, lycorine (2), 2-O-acetyllycorine (3), deacetylbowdensine (4), 1-epideacetylbowdensine (5), 8-demethyl-3-oxomaritidine (6), and (-)-marithamine (7) were isolated from the whole parts of the Crinum latifolium L. in Vietnam. The structure identification of all compounds was determined by 1D, 2D-NMR as well as HR-ESI-MS spectroscopic techniques. The absolute configuration of these compounds was established by the ECD data. In addition, in vitro inhibition of acetylcholinesterase (AChE) activities was assessed for all isolated alkaloids. All alkaloids had AChE inhibitory effects, with IC50 values ranging from 32.65 ± 2.72 to 212.76 ± 8.30 µM and compound 3 displayed the strongest inhibition of AChE, with IC50 values of 32.65 ± 2.72 µM (in comparison to the reference drug, galanthamine, which had an IC50 of 2.40 ± 0.45 µM).