Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Language
      Language
      Clear All
      Language
  • Subject
      Subject
      Clear All
      Subject
  • Item Type
      Item Type
      Clear All
      Item Type
  • Discipline
      Discipline
      Clear All
      Discipline
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
188 result(s) for "Hao Le Thi"
Sort by:
Sumoylation regulates the assembly and activity of the SMN complex
SMN is a ubiquitously expressed protein and is essential for life. SMN deficiency causes the neurodegenerative disease spinal muscular atrophy (SMA), the leading genetic cause of infant mortality. SMN interacts with itself and other proteins to form a complex that functions in the assembly of ribonucleoproteins. SMN is modified by SUMO (Small Ubiquitin-like Modifier), but whether sumoylation is required for the functions of SMN that are relevant to SMA pathogenesis is not known. Here, we show that inactivation of a SUMO-interacting motif (SIM) alters SMN sub-cellular distribution, the integrity of its complex, and its function in small nuclear ribonucleoproteins biogenesis. Expression of a SIM-inactivated mutant of SMN in a mouse model of SMA slightly extends survival rate with limited and transient correction of motor deficits. Remarkably, although SIM-inactivated SMN attenuates motor neuron loss and improves neuromuscular junction synapses, it fails to prevent the loss of sensory-motor synapses. These findings suggest that sumoylation is important for proper assembly and function of the SMN complex and that loss of this post-translational modification impairs the ability of SMN to correct selective deficits in the sensory-motor circuit of SMA mice. Sumoylation is important for the assembly and function of the SMN complex, which plays a central role in RNA processing. Here the authors show that loss of this posttranslational modification impairs the ability of SMN to correct selective deficits in the sensory-motor circuit of animal models of spinal muscular atrophy.
Target Capture Reveals the Complex Origin of Vietnamese Ginseng
The global market of the medicinal plant ginseng is worth billions of dollars. Many ginseng species are threatened in the wild and effective sustainable development initiatives are necessary to preserve biodiversity at species and genetic level whilst meeting the demand for medicinal produce. This is also the case of Panax vietnamensis Ha & Grushv., an endemic and threatened ginseng species in Vietnam that is locally cultivated at different scales and has been the object of national breeding programs. To investigate the genetic diversity within cultivated and wild populations of P. vietnamensis we captured 353 nuclear markers using the Angiosperm-353 probe set. Genetic diversity and population structure were evaluated for 319 individuals of Vietnamese ginseng across its area of distribution and from wild and a varying range of cultivated areas. In total, 319 individuals were sampled. After filtering, 1,181 SNPs were recovered. From the population statistics, we observe high genetic diversity and high genetic flow between populations. This is also supported by the STRUCTURE analysis. The intense gene flow between populations and very low genetic differentiation is observed regardless of the populations' wild or cultivated status. High levels of admixture from two ancestral populations exist in both wild and cultivated samples. The high gene flow between populations can be attributed to ancient and on-going practices of cultivation, which exist in a continuum from understorey, untended breeding to irrigated farm cultivation and to trade and exchange activities. These results highlight the importance of partnering with indigenous peoples and local communities and taking their knowledge into account for biodiversity conservation and sustainable development of plants of high cultural value.
Detection of Aflatoxins B1 in Maize Grains Using Fluorescence Resonance Energy Transfer
Aflatoxins are secondary metabolites of Aspergillus flavus and Aspergillus parasiticus. These fungal species are the most dangerous and common toxin group causing food contamination. Aflatoxin has high toxicity and can cause cancer to humans and animals. The quantitative detection of aflatoxin in food, therefore, plays a very important role. However, in practice, due to low concentrations, aflatoxin detection analysis methods need to be highly sensitive and simple to apply. In this report, the fluorescence resonance energy transfer method (FRET) adopts the donor–acceptor interaction of aflatoxin B1. The CdSe/ZnS quantum dot detection of aflatoxin B1 will be presented wherein the aflatoxin B1 concentration can be determined from the changes in fluorescence lifetime or fluorescence intensity. A fluorescence lifetime calibration curve versus aflatoxin B1 concentrations was established. Test results of aflatoxin B1 determination in maize in Vietnam by FRET method are consistent with the results of aflatoxin B1 determination by HPLC based on ppm concentration.
Prevalence of Salmonella on Chicken Carcasses from Retail Markets in Vietnam
This study was conducted to estimate the prevalence of Salmonella on chicken carcasses collected from six regions in Vietnam. A total of 1,000 whole, dressed chicken carcasses were collected from five cities and seven provinces across the six regions in Vietnam. Of these, 900 samples were collected from wet markets and 100 from supermarkets. All samples were analyzed for the presence of Salmonella according to a method recommended by the U. S. Department of Agriculture, Food Safety and Inspection Service. The overall Salmonella prevalence was 45.9%. There was no significant difference (P > 0.05) in Salmonella prevalence by (i) location (Ha Noi city, 51.1%; Hai Phong city, 45.6%; Da Nang and Can Tho cities, 45.5%; Bac Ninh province and Ho Chi Minh city, 44.7%; Dong Nai province, 44.6%; Ha Tinh province, 44.4%; Phu Tho province, 43.8%; Lao Cai province, 43.5%; Kien Giang province, 41.9%; and Lam Dong province, 40.9%), (ii) market type (wet market, 46.2%; supermarket samples, 43.0%), and (iii) storage temperature at retail (ambient storage, 46.4%; chilled storage, 45.1%). Hence, Salmonella presence on poultry meat in Vietnam was not associated with a specific city or province, market type, or storage temperature at retail. Strategies to reduce Salmonella levels on raw poultry in Vietnam should be undertaken to improve the safety of poultry products and reduce the incidence of human salmonellosis from poultry consumption.
Can a Short Food Supply Chain Create Sustainable Benefits for Small Farmers in Developing Countries? An Exploratory Study of Vietnam
A number of studies have indicated that short food supply chains could create economic, social, and environmental benefits, but most of those chains were implemented in developed countries. This research aims to find out the characteristics of short food supply chains and their benefits to small farmers in Vietnam, which is a developing country, based on the survey results from 338 small farmers in the third quarter of 2020, with the support of Stata 14 software. The results showed that the short food supply chains in the survey sample in Vietnam were characterized by two main actors: small farmers and distributors. Farmers could sell products flexibly at the local market. There was some initial evidence to prove that these chains helped to stabilize the input, output price, and revenue; formulated sustainable income; and increased the satisfaction and confidence of farmers. They eliminated gender discrimination in rural areas and improved livelihood for ethnic minorities. These chains also enhanced the mindset on green, organic, and clean production of farmers, which in turn created environmental benefits. COVID-19 has posed a negative impact on the income of farmers and made them change their production and sales method. Therefore, the research could suggest some policies to sustainably develop the short food supply chains in Vietnam in the future.
Quantification, Serovars, and Antibiotic Resistance of Salmonella Isolated from Retail Raw Chicken Meat in Vietnam
The objectives of this study were to quantify Salmonella counts on retail raw poultry meat in Vietnam and to phenotypically characterize (serovars and antibiotic resistance) the isolates. A total of 300 chicken carcasses were collected from two cities and two provinces in Vietnam. Salmonella counts on the samples were determined according to the most-probable-number (MPN) method of the U.S. Department of Agriculture, Food Safety and Inspection Service (USDA-FSIS). A total of 457 isolates were serotyped and tested for antibiotic susceptibility. Overall, 48.7% of chicken samples were Salmonella positive with a count of 2.0 log MPN per carcass. There were no significant differences (P > 0.05) in log MPN per carcass by the study variables (market type, storage condition, and chicken production system). There was a significant difference (P < 0.05) in Salmonella-positive prevalence by chicken production system. Among the 22 Salmonella serovars identified, Albany was the most frequent (34.1%), followed by Agona (15.5%) and Dabou (8.8%). Resistance to at least one antibiotic was common (i.e., 73.3%), with high resistance to tetracycline (59.1%) and ampicillin (41.6%). Resistance to three antibiotics was the most frequently found multidrug resistance profile (17.7%, n = 81); the profile that was resistant to the highest number of drugs was resistant to nine antibiotics (0.7%, n = 3). Only Salmonella Albany posed phenotypic resistance to ceftriaxone (a drug of choice to treat severe cases of salmonellosis). The data revealed that, whereas Salmonella prevalence on raw poultry was high (48.7%), counts were low, which suggests that the exposure risk to Salmonella is low. However, improper storage of raw chicken meat and cross-contamination may increase Salmonella cell counts and pose a greater risk for infection. These data may be helpful in developing risk assessment models and preventing the transmission of foodborne Salmonella from poultry to humans in Vietnam.
Estimating and forecasting bitcoin daily prices using ARIMA-GARCH models
PurposeThe goal of the study is to offer important insights into the dynamics of the cryptocurrency market by analyzing pricing data for Bitcoin. Using quantitative analytic methods, the study makes use of a Generalized Autoregressive Conditional Heteroskedasticity (GARCH) model and an Autoregressive Integrated Moving Average (ARIMA). The study looks at how predictable Bitcoin price swings and market volatility will be between 2021 and 2023.Design/methodology/approachThe data used in this study are the daily closing prices of Bitcoin from Jan 17th, 2021 to Dec 17th, 2023, which corresponds to a total of 1065 observations. The estimation process is run using 3 years of data (2021–2023), while the remaining (Jan 1st 2024 to Jan 17th 2024) is used for forecasting. The ARIMA-GARCH method is a robust framework for forecasting time series data with non-seasonal components. The model was selected based on the Akaike Information Criteria corrected (AICc) minimum values and maximum log-likelihood. Model adequacy was checked using plots of residuals and the Ljung–Box test.FindingsUsing the Box–Jenkins method, various AR and MA lags were tested to determine the most optimal lags. ARIMA (12,1,12) is the most appropriate model obtained from the various models using AIC. As financial time series, such as Bitcoin returns, can be volatile, an attempt is made to model this volatility using GARCH (1,1).Originality/valueThe study used partially processed secondary data to fit for time series analysis using the ARIMA (12,1,12)-GARCH(1,1) model and hence reliable and conclusive results.
Large-Scale Staphylococcus aureus Foodborne Disease Poisoning Outbreak among Primary School Children
A large-scale food poisoning outbreak happened at a school canteen in Ninh Binh Province, Vietnam, in 2018, resulting in the hospitalization of 352 students with clinical symptoms indicative of a staphylococcal food poisoning. A subsequent laboratory investigation detected Staphylococcus aureus in two food items—deep-fried shrimp and chicken floss—at up to 103 CFU/mL, and staphylococcal enterotoxins (SEs) in chicken floss at ≥0.211 ng SEs/g. S. aureus was also isolated from patients’ vomit and stool samples, and kitchen workers’ stool samples, as well as in frozen chicken meat, but not on the kitchen workers’ hand surfaces, suggesting the cause of this food poisoning outbreak was S. aureus contamination of the chicken meat. Molecular characterization revealed the S. aureus strains isolated from all samples were closely related; all belonged to sequence type (ST) ST6 and spa type t701 and carried both sea and sec genes. This SE-producing strain was resistant to penicillin and tetracycline, while still susceptible to oxacillin, erythromycin, gentamicin, methicillin, and vancomycin. Since S. aureus food poisonings are often underreported, our investigation added to the sparse qualitative and quantitative data of pathogenic S. aureus monitoring and surveillance in Vietnam, providing needed knowledge to guide preventative measures for future outbreaks.
Rapid Screening and Quantitative Determination of Illegal Phosphodiesterase Type 5 Inhibitors (PDE-5i) in Herbal Dietary Supplements
Phosphodiesterase type 5 inhibitors (PDE-5i) are the first-line medication for oral erectile dysfunction, which are used according to the prescription of doctors. However, these substances have been found illegally in supplementary foods. The quality and safety of dietary supplements for enhancing male sexual performance have been questioned, raising the need for continual development of analytical methods. Liquid chromatography coupled with high-resolution mass spectrometry has become one of the most effective methods to identify and measure PDE-5i concentration. In this research, we focused on (i) developing and validating an effective screening and quantitation method for more than 53 PDE-5i in ingredients and supplementary products using LC-Q-Exactive after a simple sample extraction and (ii) assessing PDE-5i content in natural-based supplementary products available in Vietnam market. The extraction method used a small amount of organic solvent, which makes it more environmentally friendly (greener). The developed method has a limit of detection of 0.4 mg/kg, a limit of quantitation of 1.2 mg/kg, recoveries from 80 to 110%, and repeatability lower than 15%. Ninety-two herbal supplementary foods and ingredients used for enhancement of male sexual performance available in Vietnamese markets were collected. Fourteen PDE-5i including conventional and novel analogous were detected and measured in eighteen food supplements and two formulation ingredient samples.
Mutation of key signaling regulators of cerebrovascular development in vein of Galen malformations
To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and most severe of congenital brain arteriovenous malformations, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP ( RASA1 ) harbored a genome-wide significant burden of loss-of-function de novo variants (2042.5-fold, p  = 4.79 x 10 −7 ). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 ( EPHB4 ) (17.5-fold, p  = 1.22 x 10 −5 ), which cooperates with p120 RasGAP to regulate vascular development. Additional probands had damaging variants in ACVRL1 , NOTCH1 , ITGB1 , and PTPN11 . ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomic analysis defined developing endothelial cells as a likely spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant (Phe867Leu) exhibited disrupted developmental angiogenesis and impaired hierarchical development of arterial-capillary-venous networks, but only in the presence of a “second-hit” allele. These results illuminate human arterio-venous development and VOGM pathobiology and have implications for patients and their families. Vein of Galen malformations (VOGMs) are severe congenital brain arteriovenous malformations. Here the authors work to elucidate the pathogenesis of VOGMs by performing an integrated analysis of 310 VOGM proband family exomes and 336,326 human cerebrovasculature single-cell transcriptomes to identify mutations of key signaling regulators.