52 research outputs found

    In vitro growth and content of vincristine and vinblastine of Catharanthus roseus L. hairy roots in response to precursors and elicitors

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    Catharanthus roseus L. is a medicinal plant that produces numerous indole terpenoid alkaloids, including vincristine and vinblastine, which are used for cancer treatment. The effect of specified precursors (L-phenylalanine, L-tyrosine) and elicitors (chitosan, methyl jasmonate) on C. roseus hairy roots (CHR) growth has been examined in order to increase the content of vincristine and vinblastine. Our results showed that CHR generated by an Agrobacterium rhizogenes strain isolated in Vietnam was capable of producing both vincristine and vinblastine when subjected to precursors, but only vinblastine when exposed to elicitors. However, both precursors and elicitors were evaluated to have an effect on increasing the accumulation of TIAs in CHR. In particular, the use of elicitors required more time to find the appropriate induction conditions, while the use of precursors gave outstanding efficiency in the treatment with 1 µM phenylalanine. The greatest yields of vincristine (51.99 µg g-1 DW) and vinblastine (699.92 µg g-1 DW) were obtained in the 7th week (with 0.306 g DW biomass). This result is the first time we might boost the levels of vincristine and vinblastine in our CHR clone generated by the Vietnam strain of A. rhizogenes

    Models to Predict the Burden of Cardiovascular Disease Risk in a Rural Mountainous Region of Vietnam

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    Objective: To compare and identify the most appropriate model to predict cardiovascular disease (CVD) in a rural area in Northern Vietnam, using data on hypertension from the communities. Methods: A cross-sectional survey was conducted including all residents in selected communities, aged 34 to 65 years, during April to August 2012 in Thai Nguyen province. Data on age, sex, smoking status, blood pressure, and blood tests (glucose, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol) were collected to identify the prevalence of high blood pressure and to use as input variables for the models. We compared three models, Asian, Chinese Multiple-provincial Cohort Study (CMCS), and Framingham, to estimate cardiovascular risk in the coming years in this context and compare these models and outcomes. Results: The prevalence of high blood pressure in these communities was lower than reported nationally (12.3%). CVD risk differed greatly depending on the model applied: approximately 21% of the subjects according to the CMCS and Asian models, but 37% using the Framingham model, had more than 10% risk for CVD. In the group without current CVD, these numbers decreased to 9% using the CMCS and Asian models but increased to 28% according to the Framingham model. There were no significant differences between the Asian and CMCS models, but differences were highly significant when comparing Asian versus Framingham or CMCS versus Framingham model. Conclusions: The Asian and CMCS models provided similar results in predicting CVD risk in the Vietnamese population in Thai Nguyen. The Framingham model provided vastly different results. The suggestion may be that for the specific Vietnamese setting, the Asian and CMCS models provide most valid and reliable results; however, this has to be investigated in further analyses using real-life data for potential confirmation. © 2014 International Society for Pharmacoeconomics and Outcomes Research (ISPOR)

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

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    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

    Developing a Sufficient Protocol for the Enhancement of α-Glucosidase Inhibitory Activity by Urena lobata L. Aeroponic Hairy Roots Using Exogenous Factors, a Precursor, and an Elicitor

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    Aeroponics is considered as a potential method for the culture of herbal plants due to the high growth rate, quantity and quality enhancement of secondary metabolites, and substantial environmental progress associated with this method. The aim of this study was to develop a sufficient protocol for successful Urena lobata hairy root induction by Agrobacterium rhizogenes ATCC 15834, using a precursor and elicitor to enhance α-glucosidase inhibitory activity (GIA) of aeroponic hairy roots (AHRs) in greenhouse conditions. In this study, we found that the optimized procedure (10 min, Woody plant medium (WPM), 1/25 salt strength) had an outstanding effect with a reduction in the rooting time (RT), promotion of the rooting rate (RR), and increase in the fresh weight (FW) and dry weight (DW) compared with the original procedure (30 min, Murashige and Skoog (MS) medium, 1/25 salt strength) after 30 days of culture. The highest DW, GIA, flavonoid (FLA) and phenolic (PHEL) contents were observed for individual addition of 10 mM phenylalanine (PA) or 50 mM chitosan (CS) in the late exponential phase (eighth week) with 15 days of elicitation compared to the control AHRs. However, individual treatment was less effective than the combination of the two. Positive correlations among the GIA, FLA and PHEL indicate that AHRs accumulated phenolic compounds, leading to an increase in the GIA by a synergistic effect. In conclusion, the culture of Urena lobata AHRs with PA and CS is an efficient procedure to produce GIA material in greenhouse conditions

    A new chromone from <i>Hymenocallis littoralis</i> Salisb. (Amaryllidaceae)

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    <div><p>A new chromone, 5,7-dihydroxy-6,8-dimethoxy-2-methyl-4<i>H</i>-chromen-4-one (<b>1</b>), together with seven known compounds, 5,7-dihydroxy-6-methoxy-2-methyl-4<i>H</i>-chromen-4-one (pisonin B) (<b>2</b>), 5,7-dihydroxy-2-methyl-4<i>H</i>-chromen-4-one (noreugenin) (<b>3</b>), 5-hydroxy-7-methoxy-2-methyl-4<i>H</i>-chromen-4-one (eugenin) (<b>4</b>), (2<i>S</i>)-7,4′-dihydroxyflavan (<b>5</b>), 3′,7-dihydroxy-4′-methoxy-8-methylflavan (<b>6</b>), 3′,7-dihydroxy-4′-methoxyflavan (<b>7</b>) and 6,8-dimethyl-5,7,4′-trihydroxyflavanone (( − )-farrerol) (<b>8</b>), were isolated from <i>Hymenocallis littoralis</i> Salisb. (Amaryllidaceae) growing in Vietnam. Their structures were determined based on spectroscopic and physicochemical analyses.</p></div

    Characteristics and dynamics of backyard poultry raising systems in five Asian countries in relation to the reduction and management of avian influenza risk : final report

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    Despite rapid growth of the poultry sector, small holders still constitute the vast majority of poultry keepers, marketed through associated informal trade networks. The research aims to better understand backyard poultry raising systems, the variations among them, their roles in rural livelihoods, and to work with stakeholders in this sector to devise practical, equitable and sustainable options to reduce the likelihood of a human Avian influenza (AI) pandemic in five Asian Countries: Cambodia, China, Indonesia, Thailand and Vietnam. This report reviews the backyard poultry system in Vietnam in terms of production, trade, gender, marketing and consumption, and information on household income

    Code-mixing in a Hong Kong secondary school

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    published_or_final_versionLinguisticsMasterMaster of Arts in Applied Linguistic

    Methane Emission Factors from Vietnamese Rice Production: Pooling Data of 36 Field Sites for Meta-Analysis

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    Rice production is a significant source of greenhouse gas (GHG) emissions in the national budget of many Asian countries, but the extent of emissions varies strongly across agro-environmental zones. It is important to understand these differences in order to improve the national GHG inventory and effectively target mitigation options. This study presents a meta-analysis of CH4 database emission factors (EFs) from 36 field sites across the rice growing areas of Vietnam and covering 73 cropping seasons. The EFs were developed from field measurements using the closed chamber technique. The analysis for calculating baseline EFs in North, Central and South Vietnam in line with the Intergovernmental Panel on Climate Change (IPCC) Tier 2 methodology was specified for the three cropping seasons being early-(E), mid-(M) and late-year (L) seasons. Calculated average CH4 EFs are given in kg ha−1 d−1 and reflect the distinct seasons in North (E: 2.21; L: 3.89), Central (E: 2.84; M+L: 3.13) and South Vietnam (E: 1.72; M: 2.80; L: 3.58). Derived from the available data of the edapho-hydrological zones of the Mekong River Delta, season-based EFs are more useful than zone-based EFs. In totality, these average EFs indicate an enormous variability of GHG emissions in Vietnamese rice production and represent much higher values than the IPCC default. Seasonal EFs from Vietnam exceeded IPCC defaults given for Southeast Asia corresponding to 160% (E), 240% (M) and 290% (L) of the medium value, respectively. View Full-Tex
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