NEAR INFRARED – EMITTING Zn2SiO4 POWDERS PRODUCED BY HIGH-ENERGY PLANETARY BALL MILLING TECHNIQUE

The near infrared-emitting Zn2SiO4 powders were produced by high-energy planetary ball milling of ZnO and SiO2 powders followed by annealing in air environment and at different temperatures. The surface morphology, crystal structure, chemical composition and optical properties of the obtained samples were investigated by means of field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Raman spectroscopy and photoluminescence measurements (PL) at room temperature. The analysis indicates the formation of Zn2SiO4 phase with annealing temperature of 1250 oC.°C. The size of Zn2SiO4 nanoparticles depends strongly on annealing temperature. Photoluminescence investigation reveals that the optimal annealing temperature for almost only near-infrared emission (~740 nm) is 1250 oC. The origin of this peak can be attributed to the energy transfer from non-bridging oxygen hole centers (NBOHs) to zinc interstialinterstitial (Zni) and oxygen vacancy (Vo) states in the Zn2SiO4 host lattice. These results demonstrate that we might be able to produce the Zn2SiO4 powders for applications in high CRI white light emitting diodes by a simple and low-cost method.

Using Bioinformatics to predict potential targets of Microrna-144 in osteoarthritis

MicroRNAs are short endogenous non-coding RNA molecules, typically 19-25 nucleotides in length, which negatively regulate gene expression through binding to 3’UTR of target mRNAs, leading to repression of protein translation or target mRNA degradation. MicroRNA-144 (miR-144) was found as an abnormal expression in various diseases, including osteoarthritis (OA). We have identified increased microRNA-144 expression in early phase and end stage of OA. However, the molecular mechanism of this increase has not been yet to be determined yet. Using bioinformatics tools, we found more than 4,000 mRNAs that are predicted to be potential direct targets of miR-144, including mRNAs involved in the critical signaling pathways in OA e.g. TGFβ/Smad2/3 and WNT/β-catenin. Results from this research provide information for future ex periments to validate miR-144 potential targets

High prevalence of plasmid-mediated quinolone resistance determinants in commensal members of the Enterobacteriaceae in Ho Chi Minh City, Vietnam

Antimicrobial-resistant pathogenic members of the Enterobacteriaceae are a well-defined global problem. We hypothesized that one of the main reservoirs of dissemination of antimicrobial resistance genes in Vietnam is non-pathogenic intestinal flora, and sought to isolate antimicrobial-resistant organisms from hospitalized patients and non-hospitalized healthy individuals in Ho Chi Minh City. The results identified substantial faecal carriage of gentamicin-, ceftazidime- and nalidixic acid-resistant members of the Enterobacteriaceae in both hospitalized patients and non-hospitalized healthy individuals. A high prevalence of quinolone resistance determinants was identified, particularly the qnrS gene, in both community- and hospital-associated strains. Furthermore, the results demonstrated that a combination of quinolone resistance determinants can confer resistance to nalidixic acid and ciprofloxacin, even in the apparent absence of additional chromosomal resistance mutations in wild-type strains and laboratory strains with transferred plasmids. These data suggest that intestinal commensal organisms are a significant reservoir for the dissemination of plasmid-mediated quinolone resistance in Ho Chi Minh City

Integrated Effect of the Payment for Forest Environmental Services (PFES) in Vietnam

Payment for forest environmental services (PFES) has become an effective management tool for forest resources in the world, especially in developing countries such as Vietnam. The Vietnamese PFES policy has been institutionalized and implemented since 2010, contributing to forest protection and improving the livelihoods of people who depend on forests. In this chapter, the PFES policy was analyzed, followed by the evaluation of the effectiveness of a PFES program applied in the Ba Be district, Bac Kan province, Vietnam in three aspects: environment, economy, and society. Finally, we synthesize the combined effectiveness of the PFES program in Vietnam and offer solutions to improve and promote the PFES policy in Vietnam and developing countries around the world

Saponins isolated from the Vietnamese sea cucumber Stichopus chloronotus.

Using various chromatographic methods, three triterpene saponins neothyonidioside (1), stichoposide D (2), and holothurin B (3), were isolated from the methanol extract of the sea cucumber Stichopus chloronotus. Their structures were elucidated by 1D and 2D-NMR experiments and comparison of their NMR data with reported values. Compound 1 was isolated from S. chloronotus for the first time

Antibiotic use and prescription and its effects on Enterobacteriaceae in the gut in children with mild respiratory infections in Ho Chi Minh City, Vietnam. A prospective observational outpatient study.

BACKGROUND AND OBJECTIVES: Treatment guidelines do not recommend antibiotic use for acute respiratory infections (ARI), except for streptococcal pharyngitis/tonsillitis and pneumonia. However, antibiotics are prescribed frequently for children with ARI, often in absence of evidence for bacterial infection. The objectives of this study were 1) to assess the appropriateness of antibiotic prescriptions for mild ARI in paediatric outpatients in relation to available guidelines and detected pathogens, 2) to assess antibiotic use on presentation using questionnaires and detection in urine 3) to assess the carriage rates and proportions of resistant intestinal Enterobacteriaceae before, during and after consultation. MATERIALS AND METHODS: Patients were prospectively enrolled in Children's Hospital 1, Ho Chi Minh City, Vietnam and diagnoses, prescribed therapy and outcome were recorded on first visit and on follow-up after 7 days. Respiratory bacterial and viral pathogens were detected using molecular assays. Antibiotic use before presentation was assessed using questionnaires and urine HPLC. The impact of antibiotic usage on intestinal Enterobacteriaceae was assessed with semi-quantitative culture on agar with and without antibiotics on presentation and after 7 and 28 days. RESULTS: A total of 563 patients were enrolled between February 2009 and February 2010. Antibiotics were prescribed for all except 2 of 563 patients. The majority were 2nd and 3rd generation oral cephalosporins and amoxicillin with or without clavulanic acid. Respiratory viruses were detected in respiratory specimens of 72.5% of patients. Antibiotic use was considered inappropriate in 90.1% and 67.5%, based on guidelines and detected pathogens, respectively. On presentation parents reported antibiotic use for 22% of patients, 41% of parents did not know and 37% denied antibiotic use. Among these three groups, six commonly used antibiotics were detected with HPLC in patients' urine in 49%, 40% and 14%, respectively. Temporary selection of 3rd generation cephalosporin resistant intestinal Enterobacteriaceae during antibiotic use was observed, with co-selection of resistance to aminoglycosides and fluoroquinolones. CONCLUSIONS: We report overuse and overprescription of antibiotics for uncomplicated ARI with selection of resistant intestinal Enterobacteriaceae, posing a risk for community transmission and persistence in a setting of a highly granular healthcare system and unrestricted access to antibiotics through private pharmacies. REGISTRATION: This study was registered at the International Standard Randomised Controlled Trials Number registry under number ISRCTN32862422: http://www.isrctn.com/ISRCTN32862422

A polyhydroxylated sterol and a saponin isolated from the starfish culcita novaeguineae

Using various chromatographic methods, a polyhydroxylated sterol 5α-cholestane-3β,6β,7α,8β,15α,16β,26-heptol (1) and an asterosaponin sodium salt of 6α-[(O-β-D-fucopyranosyl-(l®2)-O-β-D-galactopyranosyl-(l®4)-O-[β-D-quinovopyranosyl-(l®2)]-O-β-D-xylopyranosyl-(l®3)-O-β-D-quinovopyranosyl)oxy]-5α-pregn-9(11)-ene-20-one (2), were isolated from the methanol extract of the starfish Culcita novaeguineae. Their structures were elucidated by 1D and 2D-NMR experiments and comparison of their NMR data with reported values. Compounds 1 was isolated from         C. novaeguineae for the first time

Environmental entitlements: institutional influence on mangrove social-ecological systems in Northern Vietnam

Environment and development issues are complex and interdependent. Institutions underpinning state, private sector and civil society actions at various levels must address complexity to ensure social-ecological system integrity. However, responses often operate at only one governance level, with limited interactions with other levels, restricting their ability to support communities who depend on natural resources for their livelihoods. This paper explores institutional factors influencing household entitlements to mangrove system provisioning goods on Vietnam’s northern coast. The environmental entitlements framework is used to identify: (1) current formal and informal institutional structures relating to mangrove systems; (2) the influence of state, private sector and non-governmental organisation actors at various levels; and (3) how actions occurring at and among various levels of governance shape mangrove system entitlements at the local level. Employing a case study approach, this research utilises qualitative methods and a multi-level governance approach to understand prevailing institutional contexts. Results indicate that reforms occurring within weak regulatory frameworks led to the concentration of power at the meso level, reducing the endowments of marginalized households. Market forces facilitated inequality and environmental degradation, negatively impacting household entitlements. Finally, a lack of formally recognised civil society constrained household capabilities to participate in mangrove planning. Mangrove dependent households must be integrated into mangrove planning at the local level, as processes at higher institutional levels affect household environmental entitlements and threaten sustainable outcomes. Ensuring views from the local level feed into the multi-level governance process is vita