•Validation of eight Satellite-derived Precipitation Estimate (SPE) over Vietnam.•SPE datasets included uncorrected and gauge-corrected products.•GPM IMERGF-V6 achieved the best overall performance ...among SPE datasets.•There is a confidence for using SPE in determining monthly streamflow in large river basins.
This study evaluates eight Satellite-derived Precipitation Estimate (SPE) datasets, which include uncorrected SPE and gauge-corrected SPE products from Tropical Rainfall Measurement Mission Multi-satellite Precipitation Analysis (TMPA), Global Precipitation Measurement (GPM), Climate Hazards group Infrared Precipitation (CHIRP), and Precipitation Estimation form Remotely Sensed Information using Artificial Neural Networks (PERSIANN). These datasets are utilized with six representative river basins, corresponding to six sub-climate zones in Vietnam, during the period 2002–2017. The evaluations were carried out in two parts: 1) inter-comparison of the SPE products with rain gauges, for the six basins; 2) comparison of streamflow simulations, using the Soil and Water Assessment Tool (SWAT) forced by precipitation from rain gauge and SPE products. The results indicated that the gauge-corrected SPE datasets exhibited slightly better over the uncorrected datasets in comparison with rain gauges, but showed much higher performances as inputs in hydrological simulations. The GPM Integrated Multi-satellitE Retrievals for GPM (IMERG) Final run version 06B (GPM IMERGF-V6) exhibited the best overall performances among SPE products, in comparison with the rain gauges for the simulation of streamflow. This study is the first of its kind to validate GPM IMERG products in Vietnam, indicating the strong capability of the new IMERG retrieval algorithms. The CHIRP with stations (CHIRPS) dataset demonstrates a relatively low bias, could benefit long-term water resources planning for droughts. In monthly streamflow simulations, the SPE-driven simulations outperformed rain gauge-driven simulations in a larger basin (North West Region), which has low rain-gauge density. The results of this study could be a guide to determine the suitability of different SPE products for hydrological simulations.
It is essential to develop new nanomaterials able to improve sensing performance of electrochemical sensors for determination of heavy metal pollutants. In this work, a novel nanoscale ...metal–organic-framework material (Yb-MOF) with Ytterbium (Yb) rare-earth metal core and benzenetricarboxylic (BTC) ligands was prepared in aqueous conditions using hydrothermal approach. The results have revealed highly porous structure of the as-synthesized material with specific active area up to 1166 m
2
g
−1
. A sensing platform was then constructed by drop-casting Yb-MOF onto glassy carbon electrode for detection of two most commonly found heavy metal ion pollutants (Cd
2+
and Pb
2+
) in water sources. The nanoporous structure of Yb-MOF is very profitable to the selective preconcentration of targeted metal ions. The detection limits were estimated to be 3.0 ppb, 1.6 ppb for Cd
2+
and Pb
2+
species, respectively. This work provides a new electrochemical sensing platform for fast and sensitive in-situ detection of water contaminants.
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Drug resistance is a major problem in the treatment of non-small-cell lung cancer (NSCLC). In this study, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was performed to identify the ...differentially expressed genes in Adriamycin (ADR)-resistant NSCLC A549/ADR cells compared with parental A549 cells. Among the tested phytochemicals, nobiletin (NBT) is able to overcome the ADR resistance of A549/ADR cells. NBT treatment decreased the expression of a neuroblastoma-derived MYC (MYCN) and multidrug resistance-associated protein 1 (MRP1) as well as downregulating Akt, GSK3β, and β-catenin. Consistent with these results, NBT treatment resulted in the accumulation of intracellular ADR. A combination index (CI) assay confirmed the synergistic effect of combined treatment with NBT and ADR in reducing the viability of A549/ADR cells (CI = 0.152). Combined treatment with NBT and ADR enhanced apoptosis in A549/ADR cells, as evidenced by increased caspase-3 activation, poly (ADP-ribose) polymerase (PARP) cleavage, and sub-G1 population compared to treatment with ADR alone. In vivo experiments using a mouse xenograft model revealed that combination therapy with NBT and ADR significantly reduced tumor volume by 84.15%. These data suggest that NBT can sensitize ADR-induced cytotoxicity against A549/ADR cells by inhibiting MRP1 expression, indicating that NBT could serve as an effective adjuvant agent for ADR-based chemotherapy in lung cancer.
Acquired drug resistance constitutes an enormous hurdle in cancer treatment, and the search for effective compounds against resistant cancer is still advancing. Marine organisms are a promising ...natural resource for the discovery and development of anticancer agents. In this study, we examined whether gliotoxin (GTX), a secondary metabolite isolated from marine-derived
, inhibits the growth of adriamycin (ADR)-resistant non-small-cell lung cancer (NSCLC) cell lines A549/ADR. We investigated the effects of GTX on A549/ADR cell viability with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the induction of apoptosis in A549/ADR cells treated with GTX via fluorescence-activated cell sorting analysis, Hoechst staining, annexin V/propidium iodide staining, tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining, and western blotting. We found that GTX induced apoptosis in A549/ADR cells through the mitochondria-dependent pathway by disrupting mitochondrial membrane potential and activating p53, thereby increasing the expression levels of p21, p53 upregulated modulator of apoptosis (PUMA), Bax, cleaved poly (ADP-ribose) polymerase (PARP), and cleaved caspase-9. More importantly, we discovered that GTX works in conjunction with ADR to exert combinational effects on A549/ADR cells. In conclusion, our results suggest that GTX may have promising effects on ADR-resistant NSCLC cells by inducing mitochondria-dependent apoptosis and through the combined effects of sequential treatment with ADR.
Hepatitis C virus (HCV) genotype 6 is the commonest cause of chronic hepatitis C infection in much of southeast Asia, but data on the effectiveness of direct-acting antiviral agents (DAAs) against ...this genotype are limited. We conducted a retrospective cohort study of patients attending the Hospital for Tropical Diseases (HTD), Ho Chi Minh City, Vietnam, to define the effectiveness of DAAs in the treatment of chronic HCV genotype 6 in actual practice.
We included all patients with genotype 6 infections attending our hospital between March 2016 and October 2017 who received treatment with sofosbuvir-based DAA treatment regimens, and compared their responses with those with genotype 1 infections.
1758 patients (1148 genotype 6, 65.4%; 610 genotype 1, 34.6%) were analyzed. The majority of patients (1480, 84.2%) received sofosbuvir/ledipasvir (SOF/LDV) ± ribavirin (RBV); 278 (15.8%) received sofosbuvir/Daclatasvir (SOF/DCV) ± RBV. The median age of the patients was 57 years, (interquartile range (IQR) 46-64 years) The baseline HCV viral load (log IU/ml) was significantly higher in patients infected with genotype 6 compared with those infected with genotype 1 (6.8, 5.3-6.6 versus 6.3, 5.3-6.5 log10 IU/ml, p = <0.001, Mann Whitney U test). A sustained virological response (SVR), defined as an undetectable viral load measured between 12 and 24 weeks after completing treatment, and indicating cure, was seen in 97.3% (1711/1758) of patients. Treatment failure, defined as HCV viral load ≥15 IU/ml ≥12 weeks after completing treatment appeared to be more frequent in patients infected with genotype 6 virus (3.2%, 37/1148) than in those infected with genotype 1 (1.7%, 10/610), p = 0.050 chi-squared test). We found no evidence that patient's age, gender, liver cirrhosis, diabetes, HBV or HIV coinfection, prior treatment failure with pegylated interferon therapy, body mass index (BMI), aspartate aminotransferase to platelet ratio index (APRI), or fibrosis 4 (FIB-4) index were associated with treatment failure.
Our study suggests that patients with HCV genotype 6 infection in Vietnam may respond less well to treatment with sofosbuvir based DAAs than patients with genotype 1 infections. Further studies are needed to confirm this observation and to define whether it is driven by genotype-specific mutations.
The Vietnamese Mekong Delta (VMD) is located in Vietnam
The Vietnamese Mekong Delta (VMD) region has one of the leading productions of rice in the world and it stands at the intersection of extreme ...anthropogenic activity and climate change. To this end, the major focus of this study is to explore the changes in land use, climate, water resources, and their inter-relationship, which are intended to showcase the ability of publicly available earth observations and models in improving understanding of the past changes and future scenarios and contribute to improved decision making. We analyzed the change of agricultural crops (single, double, and triple) and climatic parameters (precipitation, and land surface temperature, and evapotranspiration). Consequently, we used Soil and Water Assessment Tool Model (SWAT) and selected six GCMs for extreme climate to investigate the change of streamflow.
Our results indicated that double rice crop and aquaculture are the top two land use categories in the VMD, the areas of triple rice crop have increased significantly, especially for the An Giang and Dong Thap provinces. However, by examining the climate, water, and land data analytics, we see challenges in the expansion of triple rice crop over VMD. The spatio-temporal changes in climate variables and future streamflow projections provide strong evidence to water resources managers and decision-makers in the VMD.
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•The areas of triple rice crop have increased significantly (2000–2018).•Trend of climatic variables (precipitation, temperature, and ET) are analyzed.•We selected extreme climatic scenarios for future projection on the VMD.•We simulated the projected streamflow due to extreme climatic conditions.
Middle East.
Droughts are a major natural disaster in almost every region of the world, causing negative impacts on natural resources and water basin management. However, it is challenging to study ...drought mechanisms in transboundary rivers where hydrometeorological observations are often not available or limited due to administrative issues. This study aims to assess drought conditions at three Iraqi transboundary river basins – (a) Mosul River Basin (between Iraq and Turkey), (b) Qadisiyah River Basin (between Iraq, Syria and Turkey), and (c) Dukan River Basin (between Iraq and Iran). The Famine Early Warning Systems Network Land Data Assimilation System (FLDAS) and satellite datasets have been used to calculate various drought indices and reservoir areas for the study period between 1987 and 2019.
We exhibited the usefulness of FLDAS and satellite datasets in analyzing the variations and trends in hydro-meteorological variables and reservoirs surface areas over three transboundary river basins. Results exposed a significant drought exacerbation over the study regions during the periods of 1989–1991, 2000–2003, 2007–2012, and 2015–2018. Based on our analysis on drought duration and severity for inside- and outside- Iraq, we suggest the long-term meteorological drought indices (12-,24-month timescales) in monitoring drought conditions. Our results could be beneficial for water and natural resources managers in understanding spatial variability and impact of droughts.
•Evaluation of ten different drought indices•Understanding of drought conditions based on administrative boundary•Study on three transboundary river basins across different climactic conditions
Considering increasing reports on human infections by Plasmodium knowlesi in Southeast Asian countries, blood samples collected during two large cross-sectional malariometric surveys carried out in a ...forested area of central Vietnam in 2004 and 2005 were screened for this parasite.
Blood samples collected at the 2004 survey and positive for Plasmodium malariae were randomly selected for PCR analysis detecting P. knowlesi. Blood samples collected in 2005 from the same individuals were screened again for P. knowlesi. Positive samples were confirmed by sequencing. Family members of positive cases who participated in both surveys were also screened.
Ninety-five samples with P. malariae mono- or mixed infections identified by species-specific PCR were screened for P. knowlesi. Among the five (5.2%) positive samples by PCR, three were confirmed to be P. knowlesi infections by sequencing, two young children (<5 years old) and a young man, all asymptomatic at the time of the survey and for the next six months after the survey. One of the two children was still positive one year later. No infection was found among the family members.
Plasmodium knowlesi infections in humans can be found in central Vietnam. A small child was positive for P. knowlesi in both surveys at one year interval, though it is unclear whether it was the same or a new infection.
The idea of utilizing the human immune system to eradicate tumors has been successfully practiced for the past decades, as reported in multiple published studies. Among cancer types, non-small cell ...lung cancer (NSCLC) is considered the most lethal type, leading to the necessity of finding an effective treatment for this category of cancer. Building on the success of basic and preclinical studies, numerous clinical trials of cytokine-induced killer (CIK) cells or chimera antigen receptor (CAR) T cells for NSCLC therapy have been reported. In this review paper, we will summarize those findings in the context of clinical outcomes and adverse effects. In NSCLC, compared to CAR-T cells, CIK cells show relatively stronger antitumor efficacy and lower adverse effects. More clinical studies are needed to further confirm the clinical efficiency of both types of cellular immunotherapy.
In this study, MCM-41 mesoporous silica nanoparticles were successfully synthesized by the condensation of a tetraorthosilicate precursor on a template self-assembled by cetyltrimethylammonium ...bromide in alkaline. The small-angle x-ray diffraction patterns of MCM-41 indicate that silica nanoparticles possess hexagonal structures with a high degree of structural ordering. Transmission electron microscopy images show that the size of the MCM-41 particles is around 100-120 nm, and the pore sizes range from 2 nm to 4 nm. In addition, the specific surface area of MCM-41 obtained by Brunauer–Emmett–Teller analysis is as high as 987 m
2
.g
−1
and the pore size extracted from nitrogen physical adsorption isotherms is in accordance with the TEM result. Thermogravimetric analysis, Fourier-transform infrared spectroscopy, Zeta potential measurements and photoluminescence measurements show that 3-aminopropyltriethoxysilane (APTES) and doxorubicin were grafted and loaded successfully onto MCM-41 nanoparticles. An assay on fibroblasts, A549 and doxorubicin-resistant A549/DOX cells indicates that the prepared MCM41 grafting APTES nanoparticles are safe to normal cells and toxic to cancer cells
in vitro
.
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