MTT assay has been applied widely in stimulation and inhibition tests for adherent cells. However, reading step in regular MTT assays requires medium removal to dissolve formazan by absolute solvents ...results are usually affected by incomplete formazan dissolution and protein precipitation in diluted solvents. Therefore, most of current MTT assay procedures have difficulties in application on suspension cell lines. In this study, we demonstrated a modified MTT assay in which formazan dissolution method was improved by using the combination of DMSO and SDS-lysis solution. Importantly, the modified MTT assay did not require medium removal, thus it can be applicable for both suspension and adherent cell lines. We also verified that the modified MTT procedure could be effectively applied in bioactivity assays such as cancer cell inhibition and fibroblast stimulation assays. Besides the ease of use, our data regarding nonlinear regression model fitting, data variation, and separation clearly demonstrated that the sensitivity, stability and precision of modified assay were higher than those of common MTT procedures using isopropanol or DMSO as solvents. This study indicated that the modification described here can broaden the MTT assay application on suspension cell lines and also simplify the MTT protocol on adherent cell lines.
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•This study demonstrated a modified MTT assay can be be applied in bioassays on both adherent cells and suspension cells.•Modified MTT assay coulde be applied on cell cullture without medium removal by which could reduce variety of data.•Modified MTT procedure improved sensitivity and stability of bioassay results.
The 18 plant species investigated in this study have been used as herbal antidiabetic remedies in Vietnamese traditional medicines. This study aimed to evaluate their ability to inhibit α-glucosidase ...and α-amylase, two key enzymes involved in serum glucose regulation.
Chloroform, ethanol and water extracts of 18 plants were screened for α-glucosidase and α-amylase inhibitory activity. Analytical-scale HPLC was subsequently used to investigate the most active extracts, where samples with low level of tannins were identified and fractionated into 96-well microplates, followed by α-glucosidase and α-amylase assessment of each well. High-resolution α-glucosidase and α-amylase inhibition profiles constructed from these assays allowed identification of HPLC peaks correlated with α-glucosidase and α-amylase inhibitory activity. The active constituents were subsequently isolated using preparative-scale HPLC and their structure was elucidated by HR-ESIMS and NMR.
Ethanol extracts of Nepenthes mirabilis, Phyllanthus urinaria, and Kandelia candel significantly inhibited α-glucosidase with IC50 values of 32.7±6.3, 39.7±9.7, and 35.4±13.9μg/mL, respectively. Water extracts of N. mirabilis, Phyllanthus amarus, P. urinaria, Lagerstroemia speciosa, Syzygium cumini, Rhizophora mucronata, and K. candel showed IC50 values of 3.3±0.8, 34.9±1.5, 14.6±4.6, 5.4±0.5, 20.9±1.8, 3.3±0.6, and 4.0±0.8μg/mL, respectively. In the α-amylase inhibition assay, ethanol extracts of K. candel and Ficus racemosa showed IC50 of 7.6±0.9 and 46.7±23.6μg/mL, respectively. Showing low tannin constituents as seen from HPLC profiles, P. amarus and P. urinaria water extracts and F. racemosa ethanol extract were subjected to microfractionation. Only high-resolution α-glucosidase inhibition profiles of P. amarus and P. urinaria water extracts showed several active compounds, which were isolated and identified as corilagin (1), repandusinic acid A (2), and mallotinin (3). IC50 of these compounds were 1.70±0.03, 6.10±0.10, and 3.76±0.15μM, respectively. Kinetics analysis revealed that 1 displayed a mixed type mode of inhibition with Ki and Ki′ values of 2.37±0.90 and 2.61±0.61μM, respectively, whereas 2 and 3 competitively inhibited α-glucosidase with Ki values of 4.01±0.47 and 0.65±0.11μM, respectively.
Corilagin (1), repandusinic acid A (2), and mallotinin (3) were potent α-glucosidase inhibitors contributing significantly to the inhibitory effect observed for the water extracts of P. amarus and P. urinaria.
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Two new rocaglamides, 8b-O-5-oxohexylrocaglaol (1) and elaeagnin (2), together with twelve known compounds, were isolated from the bark of Aglaia elaeagnoidea and the whole tree of A. odorata. Their ...structures were determined using spectroscopic methods, mainly 1D and 2D NMR. Cytotoxic activity against HepG2 human liver cancer cells of the isolated compounds was evaluated in vitro using the SRB assay. Three rocaglamide derivatives, dehydroaglaiastatin (13), 8b-O-5-oxohexylrocaglaol (1) and rocaglaol (5), exhibited significant effects with IC
50
values of 0.69, 4.77 and 7.37 µM, respectively.
Nine compounds including a new one, garcichaudiic acid (1), were isolated from the bark of G. gaudichaudii and their structures were characterized mainly by 1 D and 2 D NMR experiments. The ...antioxidant capacity of the isolated compounds was determined using DPPH radical scavenging assay and the anti-hyperglycemic activity was assessed by measuring the inhibitory effect against α-glucosidase. Among them, compound 4 showed higher antioxidant activity than the positive control, ascorbic acid, while both compounds 1 and 7 exhibited more significant α-glucosidase inhibitory activity than the reference drug acarbose. Molecular docking analysis of the bioactive compounds was also performed to examine the binding modes and key interactions with the catalytic site.
Background The BRAF.sup.V600E gene encodes for the mutant BRAF.sup.V600E protein, which triggers downstream oncogenic signaling in thyroid cancer. Since most currently available methods have focused ...on detecting BRAF.sup.V600E mutations in tumor DNA, there is limited information about the level of BRAF.sup.V600E mRNA in primary tumors of thyroid cancer, and the diagnostic relevance of these RNA mutations is not known. Methods Sixty-two patients with thyroid cancer and non-malignant thyroid disease were included in the study. Armed with an ultrasensitive technique for mRNA-based mutation analysis based on a two step RT-qPCR method, we analysed the expression levels of the mutated BRAF.sup.V600E mRNA in formalin-fixed paraffin-embedded samples of thyroid tissues. Sanger sequencing for detection of BRAF.sup.V600E DNA was performed in parallel for comparison and normalization of BRAF.sup.V600E mRNA expression levels. Results The mRNA-based mutation detection assay enables detection of the BRAF.sup.V600E mRNA transcripts in a 10,000-fold excess of wildtype BRAF counterparts. While BRAF.sup.V600E mutations could be detected by Sanger sequencing in 13 out of 32 malignant thyroid cancer FFPE tissue samples, the mRNA-based assay detected mutations in additionally 5 cases, improving the detection rate from 40.6 to 56.3%. Furthermore, we observed a surprisingly large, 3-log variability, in the expression level of the BRAF.sup.V600E mRNA in FFPE samples of thyroid cancer tissue. Conclusions The expression levels of BRAF.sup.V600E mRNA was characterized in the primary tumors of thyroid cancer using an ultrasensitive mRNA-based mutation assay. Our data inspires further studies on the prognostic and diagnostic relevance of the BRAF.sup.V600E mRNA levels as a molecular biomarker for the diagnosis and monitoring of various genetic and malignant diseases. Keywords: Thyroid cancer, BRAF mutation, mRNA mutation assay, Diagnosis
Abstract
Changes in the natural environment and the socio-economic environment have had both direct and indirect impacts on agricultural production and farmer’s life in three coastal districts of Ben ...Tre Province of Viet Nam, including Binh Dai, Ba Tri, and Thanh Phu. Natural environment changes are drought, saline intrusion, and landslides while the socio-economic environment changes consist of agricultural market fluctuation, rising labor and agricultural input price, decreasing output price, diseases, etc. One of the solutions that households take to cope with these changes is migration. In this article, the authors examine factors that affected households’ migrating decisions and behaviors using cost-benefit approach. Two research methods used in this study are social surveys and in-depth interviews. The survey was conducted with 79 households that have migrants in 3 coastal districts. The research suggests that migrants themselves made the migration decision in most cases (85%). Three main reasons for migration among farmers in the area have been identified as (1) solving the immediate difficulties of the household, (2) being part of the family’s long-term plan, and (3) being the family’s livelihood strategy in the short term (solving difficulties) and long-term (transforming livelihoods). The costs that migrants and their families can face are direct costs (packing, travel costs, rental housing, etc.) and indirect costs (change in living environment and social relations, anxiety of family members, and social evils at the destination, etc.). The benefits of migration can be immediate benefits (economic and non-economic) as well as long-term effects that have a great impact on household life and the migrants themselves. The research finds that migration provided more benefits related to the living conditions of households. It also points out that migration has become a feasible long-term adaptation strategy for farmers, those who stayed behind, in the context of environmental change.
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An ethyl acetate extract the bark of Garcinia xanthochymus exhibited strong inhibition towards α-glucosidase and PTP1B with IC50 values of 0.3±0.1μg/mL and 2.3±0.4μg/mL, respectively. ...Chemical constituents of the extract were therefore examined, and two new compounds, xanthochymusxanthones A (1) and B (2), along with ten known xanthones (3–12), were isolated. Their structures were determined using spectroscopic methods, mainly 1D and 2D NMR. Inhibitory activity of the isolated compounds was then tested, and subelliptenone F (12) showed significant effect towards α-glucosidase with IC50 value of 4.1±0.3μM (compared with acarbose, IC50=900.0±3.0μM) whilst xanthochymusxanthone B (2) exhibited remarkable activity towards PTP1B with IC50 value of 8.0±0.6μM (compared with RK682, IC50=4.4±0.3μM).
The green synthesized silver nanoparticles get much attention because of less toxicity, friendly environmental method, and their potential properties in various applications. Herein, the silver ...nanoparticles named as P.Gua-AgNPs or T.Ind-AgNPs are respectively fabricated by the oxidation–reduction reactions between silver ion and
Psidium guajava
or
Tamarindus indica
leaf extract. The Ultraviolet–visible spectrum of P.Gua-AgNPs appears the 429-nm peak while the peak of T.Ind-AgNPs is at 491 nm. The transmission electron microscopy and scanning electron microscope images show the P.Gua-AgNPs are spherical, triangular and plate-like polyshaped morphology in 5–53 nm, the T.Ind-AgNPs have spherical shape in 12–91 nm. The Fourier transform infrared spectra reveal that the particle surface contains the organic functional groups that is consisted with the elemental analysis from the energy dispersive X-ray analysis indicating the presence of C, O and Ag. So the
Psidium guajava
leaf extract containing abundant polyphenols, polyols, aldehyde content, and sulfur compounds creates the P.Gua-AgNPs with smaller size, narrower distribution, more diversified morphology than T.Ind-AgNPs fabricated from
Tamarindus indica
leaf extract being rich of organic acid and vitamin C. In addition, T.Ind-AgNPs and P.Gua-AgNPs show the highly antifungal ability against
Fusarium oxysporum, Aspergillus niger,
and
Aspergillus flavus
.
Several species of the sheat nematodes,
spp., have been known to cause significant damage to agricultural crops, including
,
,
,
,
, and
. Remarkably, our study reported on the presence of
for the ...first time in Vietnam. This species was found on 83.33% of the total samples with an average density of 270 individuals/100ml of soil (positive samples). In this study, the Vietnamese population of
was characterized based on both morphology and molecular characterization of D2-D3 expansion segment of 28S rRNA sequence. Besides, a molecular phylogenetic tree of the genus
was also provided.
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