Evaluation Of Allelopathic Potential Of Cissus sicyoides Against the Growth Of Echinochloa Crus-Galli And Some Tested Plants

Many plant species in nature exert significant allelopathic potential as part of the defense mechanism system, many among their secondary metabolites (allelochemicals), including mineral constituents, which are responsible for the suppression of weeds and enhancing crop yield when directly incorporated into paddy fields. Cissus sicyoides is considered a high-potential allelopathic plant because of its invasion in nature and detected allelochemicals from the plant parts in some studies. The objective of this research was to exploit the allelopathic properties of C.sicyoides against paddy weeds and some indicator plants under laboratory bioassays and greenhouse conditions. The results demonstrated that C. sicyoides had significant inhibition on E. crus-galli, tested plants, and other paddy weeds. In the laboratory conditions, the extracts from C.sicyoides leaves inhibited the growth of Echinochloa crus-galli by 54.3%. The powders from C.sicyoides leaves inhibited the emergence of paddy weeds by approximately 100.0%. In the greenhouse conditions, the powders from C.sicyoides leaves by adding after 3 and 13 days inhibited the growth of E. crus-galli and the emergence of paddy weeds by 64.4%. Remarkably, negligible harmful effects on rice growth were observed. The findings of the study may provide useful information for the exploitation of this plant species to effectively control weeds in the rice fields for sustainable agriculture production

Genetic Diversity and Population Structure of Canarium tramdenum Dai and Yakovl. in Northern Vietnam

Canarium tramdenum occurs naturally in subtropical and tropical regions of Indochina and China. The wood is used for making high quality furniture and the fruit and leaves are used in traditional medicine. However, a lack of information on genetic diversity and population structure has handicapped the genetic conservation and domestication of this high-value species. This study evaluated genetic variation within and among four C. tramdenum populations. Sixty individuals were collected from four natural populations in Vietnam in the provinces of Ninhbinh, Bacgiang, Nghean, and Backan. Genetic diversity and genetic structure were determined using 20 ISSR markers. A total of 192 DNA fragments with sizes ranging from 110 bp to 3,000 bp were detected, of which 154 segments (80.2%) were polymorphic and 38 segments (19.8%) were monomorphic. The ISSR data indicated a moderate degree of genetic diversity for the species (h = 0.252). The four populations were separated into three genetic clusters with low levels of genetic distance between them. AMOVA result showed that most (78%) of the genetic variation was within the populations. The moderate to high genetic diversity of C. tramdenum and the low genetic differentiation among populations suggested that all existing natural populations in the particular regions needed to be preserved to protect the genetic diversity of this species

Community engagement in the prevention and control of COVID-19: Insights from Vietnam.

INTRODUCTION: Community engagement (CE) is an effective public health strategy for improving health outcomes. There is limited published knowledge about effective approaches to CE in ensuring effective responses to COVID-19 throughout lockdowns, travel restrictions and social distancing. In this paper, we contribute to bridging this gap by highlighting experience of CE in Vietnam, specifically focusing on migrant workers in Vietnam. METHODS: A cross-sectional qualitative study design was used with qualitative data collection was carried out during August-October 2020. Two districts were purposefully selected from two large industrial zones. Data was collected using in-depth interviews (n = 36) with individuals and households, migrants and owners of dormitories, industrial zone factory representatives, community representatives and health authorities. Data was analyzed using thematic analysis approach. The study received ethics approval from the Hanoi University Institutional Review Board. RESULTS: The government's response to COVID-19 was spearheaded by the multi-sectoral National Steering Committee for the Prevention and Control of COVID-19, chaired by the Vice Prime Minister and comprised different members from 23 ministries. This structure was replicated throughout the province and local levels and all public and private organizations. Different activities were carried out by local communities, following four key principles of infection control: early detection, isolation, quarantine and hospitalization. We found three key determinants of engagement of migrant workers with COVID-19 prevention and control: availability of resources, appropriate capacity strengthening, transparent and continuous communication and a sense of trust in government legitimacy. DISCUSSION AND CONCLUSION: Our results support the current literature on CE in infection control which highlights the importance of context and suggests that future CE should consider five key components: multi-sectoral collaboration with a whole-of-community approach to strengthen governance structures with context-specific partnerships; mobilization of resources and decentralization of decision making to encourage self-reliance and building of local capacity; capacity building through training and supervision to local institutions; transparent and clear communication of health risks and sensitization of local communities to improve compliance and foster trust in the government measures; and understanding the urgent needs ensuring of social security and engaging all parts of the community, specifically the vulnerable groups

COVID-19 Stressors on Migrant Workers in Vietnam: Cumulative Risk Consideration.

This study explored the impact of COVID-19 on migrant workers in Vietnam, using a cumulative risk assessment (CRA) framework which comprises four domains (workplace, environment, individual and community). A cross-sectional study was conducted. Data were collected in 2020 through a self-administered questionnaire with 445 domestic migrant workers in two industrial zones in two northern provinces (Bac Ninh and Ninh Binh) in Vietnam. The majority of migrant workers were female (65.2%), aged between 18 and 29 years old (66.8%), and had high school or higher education level qualifications. Most migrant workers had good knowledge about preventive measures (>90%) and correct practices on COVID-19 prevention (81.1%). Three health risk behaviors were reported: 10% of participants smoked, 25% consumed alcohol and 23.1% were engaged in online gaming. In terms of workplace, occupational working conditions were good. Noise was the most commonly reported hazard (29%). Regarding environment, about two-thirds of migrant workers lived in a small house (<36 m2). Most participants (80.4%) lived with their families. About community domain, many reported low salary or losing their job during January-July, 2020. Most migrants received information about COVID-19. The migrant workers suffered from poor health and low occupational safety, fear of job loss and income cut, poor housing and living conditions and limited access to public services. The holistic approach to address stressors is recommended to improve health and safety of migrant workers

Use of Oral Cholera Vaccines in an Outbreak in Vietnam: A Case Control Study

Simple measures such as adequate sanitation and clean water stops the spread of cholera; however, in areas where these are not available, cholera spreads quickly and may lead to death in a few hours if treatment is not initiated immediately. The use of life-saving rehydration therapy is the mainstay in cholera control, however, the rapidity of the disease and the limited access to appropriate healthcare units in far-flung areas together result in an unacceptable number of deaths. The WHO has recommended the use of oral cholera vaccines as a preventive measure against cholera outbreaks since 2001, but this was recently updated so that vaccine use may also be considered once a cholera outbreak has begun. The findings from this study suggest that reactive use of killed oral cholera vaccines provides protection against the disease and may be a potential tool in times of outbreaks. Further studies must be conducted to confirm these findings

A Multi-Center Randomised Controlled Trial of Gatifloxacin versus Azithromycin for the Treatment of Uncomplicated Typhoid Fever in Children and Adults in Vietnam

BACKGROUND: Drug resistant typhoid fever is a major clinical problem globally. Many of the first line antibiotics, including the older generation fluoroquinolones, ciprofloxacin and ofloxacin, are failing. OBJECTIVES: We performed a randomised controlled trial to compare the efficacy and safety of gatifloxacin (10 mg/kg/day) versus azithromycin (20 mg/kg/day) as a once daily oral dose for 7 days for the treatment of uncomplicated typhoid fever in children and adults in Vietnam. METHODS: An open-label multi-centre randomised trial with pre-specified per protocol analysis and intention to treat analysis was conducted. The primary outcome was fever clearance time, the secondary outcome was overall treatment failure (clinical or microbiological failure, development of typhoid fever-related complications, relapse or faecal carriage of S. typhi). PRINCIPAL FINDINGS: We enrolled 358 children and adults with suspected typhoid fever. There was no death in the study. 287 patients had blood culture confirmed typhoid fever, 145 patients received gatifloxacin and 142 patients received azithromycin. The median FCT was 106 hours in both treatment arms (95% Confidence Interval [CI]; 94-118 hours for gatifloxacin versus 88-112 hours for azithromycin), (logrank test p = 0.984, HR [95% CI] = 1.0 [0.80-1.26]). Overall treatment failure occurred in 13/145 (9%) patients in the gatifloxacin group and 13/140 (9.3%) patients in the azithromycin group, (logrank test p = 0.854, HR [95% CI] = 0.93 [0.43-2.0]). 96% (254/263) of the Salmonella enterica serovar Typhi isolates were resistant to nalidixic acid and 58% (153/263) were multidrug resistant. CONCLUSIONS: Both antibiotics showed an excellent efficacy and safety profile. Both gatifloxacin and azithromycin can be recommended for the treatment of typhoid fever particularly in regions with high rates of multidrug and nalidixic acid resistance. The cost of a 7-day treatment course of gatifloxacin is approximately one third of the cost of azithromycin in Vietnam. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN67946944

Emerging Role of Circulating Tumor Cells in Gastric Cancer

With over 1 million incidence cases and more than 780,000 deaths in 2018, gastric cancer (GC) was ranked as the 5th most common cancer and the 3rd leading cause of cancer deaths worldwide. Though several biomarkers, including carcinoembryonic antigen (CEA), cancer antigen 19-9 (CA19-9), and cancer antigen 72-4 (CA72-4), have been identified, their diagnostic accuracies were modest. Circulating tumor cells (CTCs), cells derived from tumors and present in body fluids, have recently emerged as promising biomarkers, diagnostically and prognostically, of cancers, including GC. In this review, we present the landscape of CTCs from migration, to the presence in circulation, biologic properties, and morphologic heterogeneities. We evaluated clinical implications of CTCs in GC patients, including diagnosis, prognosis, and therapeutic management, as well as their application in immunotherapy. On the one hand, major challenges in using CTCs in GC were analyzed, from the differences of cut-off values of CTC positivity, to techniques used for sampling, storage conditions, and CTC molecular markers, as well as the unavailability of relevant enrichment and detection techniques. On the other hand, we discussed future perspectives of using CTCs in GC management and research, including the use of circulating tumor microembolies; of CTC checkpoint blockade in immunotherapy; and of organoid models. Despite the fact that there are remaining challenges in techniques, CTCs have potential as novel biomarkers and/or a non-invasive method for diagnostics, prognostics, and treatment monitoring of GC, particularly in the era of precision medicine

Genetic diversity of naturally distributed Rhododendron moulmainense Hook. f. populations in Lam Vien Plateau, Vietnam revealed by ISSR and SCoT markers

Genetic diversity and variation of three naturally distributed Rhododendron moulmainense populations in the Lam Vien Plateau of Vietnam were analyzed using ISSR and SCoT markers separately and data from the two types of markers were then combined to show the overall results. Based on combined data, the genetic diversity parameters of the Tuyen Lam population were percentage of polymorphic bands (PPB) = 28.79%; genetic heterozygosity (He) = 0.1041; Shannon index (I) = 0.1552. The corresponding parameters were PPB = 37.88%; He = 0.1434; I = 0.2131 in the Hon Nga population, and PPB = 46.21%; He = 0.1857; I = 0.2709 in the Bidoup population. At the species level in Lam Dong province, the corresponding parameters were PPB = 62.12%; He = 0.1747; I = 0.2756. The average of pairwise genetic similarity coefficients among investigated individuals of Tuyen Lam population was 0.973, of Hon Nga population was 0.911, and of Bidoup population was 0.895. The genetic differentiation and the number of migrants per generation among investigated populations were GSTS = 0.1735 and Nm = 2.3824 individuals, respectively. Genetic distance between Tuyen Lam and Hon Nga populations was 0.0399, between Tuyen Lam and Bidoup populations were 0.0621, and Bidoup and Hon Nga populations were 0.0670. Data generated by both marker types and the combined revealed similar trends of genetic diversity levels among the studied populations. The SCoT data showed higher values of genetic diversity and population gene differentiation than did the ISSR data, but the latter showed higher gene differentiation among sampled individuals in the study populations. Comparing the values of Polymorphism Information Content (PIC) for discriminatory ability; Effective Multiplex Ratio (EMR) for several revealed loci and/or efficiency of the primer-marker system; Marker Index (MI) for the efficiency of used method; and Resolving Power (Rp) between used techniques indicated that discriminatory ability, efficiency, and ability of the ISSR primer combinations were higher but using SCoT marker system was more efficient than ISSR marker system for evaluating genetic diversity

A New Approach of Fabricating Graphene Nanoplates@Natural Rubber Latex Composite and Its Characteristics and Mechanical Properties

Graphene has been demonstrated to be one of the most promising candidates to use as filler to improve the electrical, thermal, chemical and mechanical properties of natural rubber due to exceptional high surface area, superior electrical and thermal conductivity, and remarkable gas impermeability resistance. In this study, graphene nanoplates (GNPs) were mass-produced by a one-step chemical exfoliation of natural graphite and used as a filler for the fabrication of GNPs@natural rubber composite by a simple mixing method. The resultant GNPs/rubber composite was characterized by using scanning electron microscopy (SEM), and a rheometer. The prepared graphene nanoplates had a thickness of less than 10 nm and a lateral size of tens of microns. The GNPs@rubber composite revealed an exceptional improvement of abrasion loss up to seven to ten fold, along with an approximately 400%, 200% and 30% increment of elongation at break, tear strength and tensile strength, respectively. Other mechanical properties, such as hardness, compression set and rebound, as well as the effect of the GNPs loadings on the mechanical properties of the composite, were also investigated in detail

Community engagement in the prevention and control of COVID-19: Insights from Vietnam. Qualitative transcripts.

Interview transcripts related to a research study that investigated the use of community engagement assessment to combat Covid-19 among migrant workers working in industrial zones in Vietnam. Files are held on Figshare