Antimicrobial Activities and Mechanisms of Magnesium Oxide Nanoparticles (nMgO) against Pathogenic Bacteria, Yeasts, and Biofilms.

Magnesium oxide nanoparticle (nMgO) is a light metal based antimicrobial nanoparticle that can be metabolized and fully resorbed in the body. To take advantage of the antimicrobial properties of nMgO for medical use, it is necessary to determine the minimal inhibitory, bactericidal and fungicidal concentrations (MIC, MBC and MFC) of nMgO against prevalent infectious bacteria and yeasts. The objective of this study was to use consistent methods and conditions to reveal and directly compare the efficacy of nMgO against nine prevalent pathogenic microorganisms, including two gram-negative bacteria, three gram-positive bacteria with drug-resistant strains, and four yeasts with drug-resistant strains. The MIC of nMgO varied from 0.5 mg/mL to 1.2 mg/mL and the minimal lethal concentration (MLC) of nMgO at 90% killing varied from 0.7 mg/mL to 1.4 mg/mL against different pathogenic bacteria and yeasts. The most potent concentrations (MPC) of nMgO were 1.4 and/or 1.6 mg/mL, depending on the type of bacteria and yeasts tested. As the concentration of nMgO increased, the adhesion of bacteria and yeasts decreased. Moreover, S. epidermidis biofilm was disrupted at 1.6 mg/mL of nMgO. E. coli and some yeasts showed membrane damage after cultured with ≥0.5 mg/mL nMgO. Overall, nMgO killed both planktonic bacteria and disrupted nascent biofilms, suggesting new antimicrobial mechanisms of nMgO. Production of reactive oxygen species (ROS), Ca2+ ion concentrations, and quorum sensing likely contribute to the action mechanisms of nMgO against planktonic bacteria, but transient alkaline pH of 7 to 10 or increased Mg2+ ion concentrations from 1 to 50 mM showed no inhibitory or killing effects on bacteria such as S. epidermidis. Further studies are needed to determine if specific concentrations of nMgO at MIC, MLC or MPC level can be integrated into medical devices to evoke desired antimicrobial responses without harming host cells

SKILLS TO COPE WITH LEARNING STRESS OF STUDENTS IN CAN THO UNIVERSITY, VIETNAM

The research on the topic has systematized the theoretical basis of students' skills to cope with stress in learning. Currently, students face a lot of pressure and stress in their studies, so coping skills are an extremely important issue and need attention. The study presents the manifestations of skills to cope with stress in the learning of students of School of Education at Can Tho University (CTU), Vietnam. The research mainly uses a questionnaire survey method with 400 students from various fields of study, SoE, CTU. According to survey results, there were many manifestations of stress that students encountered. The survey results are the basis for finding the causes so students can plan and manage their time, set specific goals to find effective remedies, adapt and manage better emotions. From the current situation of the problem, the study has proposed measures to support students' skills to cope with stress in their studies. This study provides recommendations to deploy and apply the research results to Can Tho University lecturers and students as well.  Article visualizations

SOCIAL-EMOTIONAL SKILLS IN STUDENTS’ LEARNING IN CAN THO UNIVERSITY, VIETNAM

Based on an overview of domestic and foreign research related to the research field of the topic; the research of the topic has determined the urgency of the topic, research objectives, research objects and scope, research hypotheses, research tasks, and methods. The research on the topic has systematized the theoretical basis for the concept and manifestation of social-emotional skills in student learning: generalizing the picture of the current situation of recognizing the importance of social-emotional skills in student learning, the level of assessment of the manifestation and educational measures of social-emotional skills in learning, and finding out the factors that affect social emotions in student learning such as from the external environment, at school, family and external social relationships. Factors from the internal environment are the self-awareness of each student. From the current situation of the problem, the study has proposed educational measures for 504 students from 8 schools and colleges in Can Tho University (CTU), Vietnam. Some measures were to educate social-emotional skills for students through soft skills topics, teach soft skills to students through extracurricular activities, and soft skills education for students through integrated teaching.  Article visualizations

Synthesis and application of Fe3O4/GO/PVP composite material for methylene blue adsorption

In this study, Fe3O4/GO/PVP (FGP) was successfully synthesized and efficiently applied for absorbing methylene blue. First, GO was synthesized by Hummer’s method from waste home-batteries. The chemical co-precipitation method was used to fabricate Fe3O4/GO from a mixture solution of GO, Fe3+, Fe2+. Polyvinylpyrrolidone PVP was selected to functionalize Fe3O4/GO and form Fe3O4/GO/PVP for improving dispersibility purpose in aqueous solution. The obtained Fe3O4/GO/PVP was characterized by XRD, FT-IR, BET, FE-SEM, UV-Vis techniques. Moreover, the effecting factors as pH, time adsorption, initial concentration of methylene blue were conducted. Adsorption isotherm models were also identified. The results showed that specific surface area of FGP-3 was 70.0 m2.g-1, the Freundlich isotherm model was suitable and the Dubinin - Radushkevich isotherm model showed that the process was physical adsorption. The maximum capacity (qmax) was 30.4 mg.g-1. These findings prove Fe3O4/GO/PVP as an inexpensive and efficient adsorbent for removal of cationic dyes

Natural Radioactivity in Commonly Building Materials Used in Vietnam - 11255

ABSTRACT Naturally occurring radionuclides in building materials contribute to external and internal exposure and that is necessary to be investigated. In the research, 213 samples of 11 different kinds of commonly used structural and covering building materials were collected from housing and other building construction sites and from suppliers in Vietnam to measure the natural radioactivity of Ra-226, Th-232 and K-40. The measurements were carried out using low background gamma-ray spectrometry with HPGe detector. The specific activities of the different building materials varied from 0.18 -395.28, 0.10 -266.52 and 0.76 -2006.78 Bq/kg with the average values of 52.09, 55.70 and 593.5 Bq/kg for Ra-226, Th-232 and K-40, respectively. The obtained data were compared with the corresponding reported data of other countries. The activity concentration index and the annual effective dose were evaluated to assess the potential radiological hazard associated with these building materials. The results showed that the enhanced concentration values were sometimes felling into granite tiles, especially imported granite tiles. These obtained data aimed to enlarge the database on natural radioactivity in commonly building materials used in Vietnam and to support technical aspects in hazard exposure reduction

Early Pandemic Influenza (2009 H1N1) in Ho Chi Minh City, Vietnam: A Clinical Virological and Epidemiological Analysis

Rogier van Doorn and colleagues analyze the initial outbreak, attempts at containment, and establishment of community transmission of pandemic H1N1 influenza in Ho Chi Minh City, Vietnam

The Sudden Dominance of blaCTX–M Harbouring Plasmids in Shigella spp. Circulating in Southern Vietnam

Shigellosis is a disease caused by bacteria belonging to Shigella spp. and is a leading cause of bacterial gastrointestinal infections in infants in unindustrialized countries. The Shigellae are dynamic and capable of rapid change when placed under selective pressure in a human population. Extended spectrum beta lactamases (ESBLs) are enzymes capable of degrading cephalosporins (a group of antimicrobial agents) and the genes that encode them are common in pathogenic E. coli and other related organisms in industrialized countries. In southern Vietnam, we have isolated multiple cephalosporin-resistant Shigella that express ESBLs. Furthermore, over two years these strains have replaced strains isolated from patients with shigellosis that cannot express ESBLs. Our work describes the genes responsible for this characteristic and we investigate one of the elements carrying one of these genes. These finding have implications for treatment of shigellosis and support the growing necessity for vaccine development. Our findings also may be pertinent for other countries undergoing a similar economic transition to Vietnam's and the corresponding effect on bacterial populations

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security