Addition Of MT Research Articles

Transmembrane and transcriptome analysis reveals the mechanism of dietary supplements in reducing cadmium absorption and toxicity

Dietary strategies have proven to be effective in preventing cadmium (Cd) poisoning, but the regulation of the bioavailability (BAV) and transport of Cd in the body, as well as their molecular mechanisms remain unclear. In this study, the Caco-2 cell models were applied to investigate the effects of 15 dietary supplements on Cd bioavailability (Cd-BAV) in Cd-contaminated water through a transmembrane transport assay and the mechanisms of three selected supplements in inhibiting Cd toxicity and uptake. The results demonstrated that the Cd-BAV in water varied from 7.89 % to 18.4 % using simulated gastrointestinal digestion and cell model. The addition of MT, Zn, and OPCs significantly reduced Cd-BAV by 82.5 %, 73 % and 60.5 % and also strengthened transmembrane electrical resistance (TEER), indicating the protective effects of these compounds against Cd-induced barrier dysfunction. Moreover, the results of transcriptomics revealed that these components can modulate the expression of specific pathway genes associated with the toxicity and absorption of dietary Cd, such as the apoptosis pathway (Jun, Ddit3), antioxidant-related pathways (Cat, Hmox1), and mineral absorption pathway (Mt, Slc39a4). This study highlights the importance of potential dietary interventions in public health and suggests that developing more effective measures to promote safer food consumption would be beneficial.

CHITOSAN AND META-TOPOLIN SUPPLEMENTATION OF THE MULTIPLICATION MEDIA OF VITIS VINIFERA L.

We investigated the efficiency of chitosan (CH) and meta-topolin (mT) on in vitro growth and adaptation to greenhouse conditions of Vitis vinifera cv. Johanniter and cv. Hibernal. After the initiation stage, we transferred explants to Woody Plant Media (WPM) with chitosan (molecular weight 3.33 kDa) at a concentration of 10, 20, and 40 ppm or to WPM with mT at a concentration of 0.5, 1.0, and 2.0 mg l–1. WPM without CH or mT served as a control. Among the tested combinations, WPM with 10 ppm of CH led to the maximum mean root length (12.18 cm and 12.65 cm for the Hibernal and Johanniter cultivars, respectively) and the number of new leaves (5.9 and 8.15 for the Hibernal and Johanniter cultivars, respectively). As the CH concentration in the medium increased, the length of shoots and roots decreased. We found the highest percentage of acclimatised plants on WPM (cv. Hibernal) and WPM with 40 ppm of CH (cv. Johanniter). The addition of mT had a negative effect on the morphological traits we measured, regardless of the concentration. Leaves of explants from WPM with mT were yellower and redder compared with the control. None of the explants obtained on this medium produced roots.

Investigation of Growth Factors and Mathematical Modeling of Nutrient Media for the Shoots Multiplication In Vitro of Rare Plants of the Rostov Region

Micropropagation is an effective way to preserve the gene pool of threatened plants. This study is devoted to the mathematical modeling of nutrient media and the study of the effect of mT (meta-topoline) on the multiplication of shoots of Hedysarum grandiflorum, Hyssopus cretaceus, and Matthiola fragrans in vitro in comparison with benzylaminopurine (BAP) and kinetin (KT). Initiation was performed on an MS medium with 0.5 mg/L BAP. For shoots multiplication, MS, B5, and WPM media were used with the addition of mT, BAP, KT. For H. grandiflorum, the multiplication coefficient of shoots was highest on medium B5 with the addition of mT at a concentration of 1 mg/L—2.90 shoots per plant, for H. cretaceus—B5 + 0.5 mg/L mT, and for M. fragrans—B5 + 1 mg/L KT. A positive effect of mT on H. grandiflorum and M. fragrans in vitro was found. The efficiency of using KT for H. cretaceus shoot multiplication is shown. The effectiveness of the B5 nutrient medium for H. grandiflorum and M. fragrans was determined. The positive effect of WPM for H. cretaceus micropropagation has been demonstrated. It is not recommended to use the MS media for micropropagation of these plant species.

Chromium Transport and Fate in Vadose Zone: Effects of Simulated Acid Rain and Colloidal Types.

Chromium (Cr) can enter groundwater through rainfall infiltration and significantly affects human health. However, the mechanisms by which soil colloids affect chromium transport are not well investigated. In this study, column experiments were conducted to simulate the chromium (Cr) transport mechanism in two typical soils (humic acid + cinnamon soil and montmorillonite + silt) in the vadose zone of a contaminated site and the effects of acid rain infiltration conditions. The results showed that Mt colloids have less influence on Cr. The fixation of Cr by colloid mainly occurs in the cinnamon soil layer containing HA colloid. The adsorption efficiency of Cr was increased by 12.8% with the addition of HA. In the HA-Cr system, the introduction of SO42- inhibited the adsorption of Cr, reducing the adsorption efficiency from 31.4% to 24.4%. The addition of Mt reduced the adsorption efficiency of Cr by 15%. In the Mt-Cr system, the introduction of SO42- had a promoting effect on Cr adsorption, with the adsorption efficiency increasing from 4.4% to 5.1%. Cr release was inhibited by 63.88% when HA colloid was present, but the inhibition owing to changes in acidity was only 14.47%. Mt colloid promotes Cr transport and increases the leaching rate by 2.64% compared to the absence of Mt. However, the effect of acidity change was not significant. Intermittent acid rain will pose a higher risk of pollutant release. Among the influencing factors, the type of colloid had the most significant influence on the efficiency of Cr leaching. This study guides the quantitative assessment of groundwater pollution risk caused by Cr in the vadose zone.

Effects of montmorillonite on the adsorption of Fe(II) by ferrihydrite and its phase transformation at different pH.

Recently, there has been a clear understanding of the mechanism and influencing factors of ferrihydrite (Fh) phase transformation catalyzed by Fe(II); however, these factors mainly belong to environmental conditions and exogenous substances. And there is a lack of research on the effect of soil composition and structure on the phase transformation of Fh. Therefore, this study investigated the effects of montmorillonite (Mt) on the adsorption of Fe(II) and phase transformation of Fh under near-neutral pH. The initial rates ([Formula: see text]) of Elovich equation demonstrated the addition of Mt inhibited the adsorption of Fh but simultaneously accelerated the initial adsorption, thus increasing the adsorption of the system (e.g., 22.09-25.03mg/g as increased Mt under pH 6.5) due to its high surface charge density. Increased pH enhances the surface charge density by promoting the deprotonation of the surface group (Fe-OH, Al-OH, and Si-OH) and consequently increases adsorption of Fe(II) (e.g., 17.97-22.09mg/g as increased pH of pure Fh). Based on the previous method of extracting labile Fe(III), we found that pH promotes the initial formation of labile Fe(III) by increasing electron transfer and promoting recrystallization caused by bridging condensation, via increased -OH. Although Mt inhibits the adsorption of Fh, it promotes the formation of labile Fe(III) by increasing the system adsorption and bond with Fh. The results of the analysis of variance showed both pH and solid ratio influence significantly on the maximum adsorption (p = 6.81 × 10-9 and 2.54 × 10-3) and the conversion ratios of labile Fe(III) (p = 3.43 × 10-24 and 9.16 × 10-43).

Catalytic capacity evolution of montmorillonite in in-situ combustion of heavy oil

Clay minerals such as montmorillonite are significant in petroleum storage and recovery. Montmorillonite (Mt) is a natural solid acid catalyst containing Brønsted and Lewis acid sites and can catalyze heavy oil oxidation (HOO) during in-situ combustion (ISC). However, its catalytic activity largely depends on the heating process of heavy oil. In the study, the catalytic capacity evolution of Mt in ISC of heavy oil was explored with the isoconversional method and thermal analysis. In low-temperature oxidation (LTO) and high-temperature oxidation (HTO) stages, the addition of Mt largely reduced the peak temperatures (Tpeak) of DTA and DTG and the Tpeak of H2O (LTO and HTO stages) and CO2 (HTO stage) in HOO. Notably, Mt did not always show the positive catalytic effect. In LTO stage, the thermal transformation process had a small effect on DTA Tpeak, Tpeak of H2O and CO2, and the reaction activation energy (Eα) of HOO. In HTO stage, the catalytic effect of Mt on HOO was related to its thermal transformation process, especially interlayer water (IW) dehydration and dehydroxylation. In HTO stage, the IW dehydration process of Mt showed the strongest catalytic effect on HOO, significantly reduced DTA Tpeak and Eα, and resulted in the lowest Tpeak of H2O and CO2. The dehydroxylation process of Mt also showed a certain effect, whereas the overlapping process between the dehydration (IW) reaction and partial dehydroxylation reaction of Mt had no positive catalytic effect on HOO. DTA, TG-FTIR, and non-isothermal kinetic analysis further confirmed that the catalytic capacity of Mt in HTO stage was improved by IW dehydration process of Mt and weakened by the dehydroxylation process of Mt.

Determination of 17α-methyltestosterone in aquatic products using high-performance liquid chromatography-tandem mass spectrometry

17α-methyltestosterone (MT) is widely used in aquaculture in order to increase harvest yield. However, illegal addition of MT is potentially toxic to human. A simple and rapid method for the determination of MT in aquatic products was established on HPLC-MS/MS. Sample preparation was optimized using simple liquid–liquid extraction techniques with ethyl acetate and n-hexane. The analyte was separated on Capcell PAK C18 MG II (100 mm × 2.0 mm, 5 µm), with a solution of 0.1 % formic acid in water and acetonitrile, and analyzed with multiple-reaction monitoring (MRM) mode on HPLC-MS/MS. Good linearity with high correlation coefficient (R2 ≥ 0.9997) was obtained between 2 and 200 µg/L. The limits of detection (LODs) and quantitation (LOQs) were 0.4 and 1 µg/kg respectively. Good recoveries were demonstrated between 86.4 and 104.6 %. The precisions of inter-day and intra-day were validated and the results indicated acceptable stability and reproducibility. The analyte showed stable up to 30 days storage at −20 °C. Samples purchased from Shanghai market for each matrix (shrimp, Chinese mitten crab, tilapia, eel, bullfrog and mussel) were tested for method application. In summary, the proposed method was validated for MT determination in aquatic products.

Rapid Quantitative Detection of Melatonin By Electrochemical Sensor Based on Carbon Nanofibers with Embedding FeCo Alloy Nanoparticles

IntroductionMelatonin (MT), as an efferent hormonal signal of the circadian clock, is an indoleamine neuroendocrine hormone synthesized and secreted principally by the pineal gland at night under normal environmental conditions [1]. Melatonin exerts various physiological functions by binding to melatonin receptors, including regulating day and night rhythms, inhibiting tumor development, and regulating immunity [2]. In present work, we prepared an electrochemical sensor that can quickly detect melatonin and further studied the its electrooxidation behavior and reaction mechanism. This sensor is based on carbon nanofibers with FeCo bimetallic alloy dispersed and embedded in (FeCo@CNFs) by electrospinning and a thermal treatment process. Through the analysis and comparison of various characterization methods, it can be proved that the combination of bimetal and CNF can improve the electrochemical properties of the composites. We also analyzed the electrochemical behavior of melatonin at the FeCo@CNFs electrode. Compared with previous reports on melatonin detection, this sensor has a lower detection limit and a wider detection range.Characterization of FeCo@CNFsIn Fig. 1A, the SEM image FeCo@CNFs have a homogeneous fiber structure with a diameter of approximately 100~200 nm. And it can be seen from its HRTEM images that the FeCo@CNFs are porous structure and decorated with nanoparticles (Fig. 1B). Moreover, it can be seen from Fig. 1C that the obvious lattice fringes are 0.19 nm and 0.33 nm, corresponding to (110) crystalline facet of FeCo alloy and (002) crystalline facet of graphitized carbon layer respectively, indicating that FeCo is wrapped by graphitized carbon fibers. It is well known that transition metals such as Fe and Co can not only promote the transformation of adjacent amorphous carbon to graphitized carbon, but also change the electron interaction between host and guest, reduce the local work function of carbon layer and promote the electrocatalytic reaction[3].Results and ConclusionsFig. 1D shows the I-T curve of detection of MT in the stirring PB solution (pH 5.0) at FeCo@CNFs/GCE with the concentration ranging from 0.08μM to 400μM. It can be seen that the current response increases linearly with the increase of MT. The current response increased linearly with successive addition of MT and the linear relationship is Ip (μA) = 0.537 + 0.038C (μM) (R = 0.997) (Fig. 1E). The detection limit is estimated to be 2.7×10-9 mol L-1 (S/N=3).

Immobilized chitosan-montmorillonite composite adsorbent and its photocatalytic regeneration for the removal of methyl orange

In this study, chitosan and clay-montmorillonite (CS-MT) composite was prepared and immobilized on glass plates for the removal of methyl orange (MO) dye from aqueous solution. The immobilized CS-MT was characterized using scanning electron microscopy-energy dispersive X-ray (SEM–EDX), Fourier transform infrared (FTIR), pore structural analysis and UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS). The addition of MT into the CS matrix produced a heterogeneous surface and slightly increased the surface area of the composite film. The adsorption study revealed that the pseudo-second-order kinetic and Langmuir isotherm models could well describe the adsorption of MO dye onto the immobilized CS-MT. After saturation, the spent CS-MT was regenerated via the TiO2 photocatalytic oxidation under UV–Vis irradiation. During the regeneration, the spent CS-MT underwent two concurrent processes: desorption of MO dye and photocatalytic oxidation of desorbed dye by the TiO2 photocatalyst. The photocatalytic regeneration of the spent immobilized CS-MT was highly effective in ultra-pure water at pH 11, as it mineralized up to 86% of the desorbed MO within 20 h of regeneration time.

Electroconductive and catalytic performance of polypyrrole/montmorillonite/silver composites synthesized through in situ oxidative polymerization

ABSTRACTThe present study demonstrates a simple approach to the formation of polypyrrole/montmorillonite/silver (PPy/Mt/Ag) composites via in situ oxidative polymerization of pyrrole (Py) in the presence of AgNO3 acting as a direct oxidant. The polymerization was performed in the presence of dodecylbenzenesulfonic acid, which acts as a stabilizing and doping agent. The morphological, structural, and thermal properties of PPy/Mt/Ag composites are discussed in detail and a possible formation mechanism is proposed. The electrical conductivities of the composites pressed at different pressing pressures were investigated using four‐probe analyzer. X‐ray diffraction, transmission electron microscopy, and scanning electron microscopy results indicated the partially exfoliated structure of the composites and Fourier transforms infrared results suggested the strong interactions between SiOSi groups in Mt and NH groups in PPy chains. The addition of Mt in the PPy polymer enhanced thermal property of the polymer. The conductivity of 1.08 S cm−1 was observed in the sample with 20 wt % Mt loading and applied pressure of 5 MPa. The composites obtained in the present study catalyze the reduction of methylene blue by sodium borohydride, achieving 92% conversion of MB to colorless within a few minutes. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45986.

Enhanced temperature stability and fatigue-resistant behavior in MgTiO3-doped 0.948(K0.5Na0.5)NbO3–0.052LiSbO3 lead-free ceramics

0.948(K0.5Na0.5)NbO3–0.052LiSbO3–xMgTiO3 (x=0, 0.005 and 0.010) (abbreviated as KNLNS–xMT) lead-free piezoelectric ceramics were prepared by normal sintering. The effect of MT addition on KNLNS ceramics was investigated through dielectric, ferroelectric and electric field-induced strain characterizations. The grain size decreased slightly after the addition of MT, and more uniform grains were obtained. Impedance measurements made over a wide range of temperatures (425–525°C) showed the presence of both bulk and grain boundary effects in the materials. The activation energies Ea were 0.483 and 0.507eV for KNLNS and KNLNS–0.005MT ceramics respectively, indicating that the conduction process was due to oxygen vacancies in the higher temperature region. The Pr and unipolar strain of the MT modified ceramics exhibited lower temperature sensibility than KNLNS ceramics in the temperature range 30–120°C. Meanwhile, the MT doped samples showed less degradation in both switchable polarization and unipolar strain after 106 switching cycles than those of KNLNS. It is expected that the KNLNS–xMT ceramics is promising candidate for lead-free piezoceramics and could be used in practical applications.

Montmorillonite for starch-based barrier dispersion coating — Part 1: The influence of citric acid and poly(ethylene glycol) on viscosity and barrier properties

Starch-based coating formulations were draw-down coated on a paper substrate and the effect on the water vapor transmission rate, WVTR, upon montmorillonite, Mt addition was compared to that of the pure starch matrix and for poly(ethylene glycol), PEG, or citric acid, CA, as potential plasticizers. Both PEG and CA were added at a ratio of 3 to 10 to starch. Addition of CA to the starch substantially lowered the WVTR of the coated papers compared to coating with pure starch or PEG plasticized starch. The WVTR of the papers coated with just starch and CA was lower than that obtained for paper coated with the non-plasticized Mt–starch dispersion, and approximately the same as paper coated with Mt–starch dispersions plasticized with PEG or CA. Addition of Mt was effective in reducing the WVTR in the case of starch plasticized by PEG but not with CA. These differences in WVTR reduction were indicated to be due to differences in the viscosity and clay swelling indicating that CA and PEG affected the Mt dispersion differently. CA was also investigated as a dispersing agent by addition in small quantities to the montmorillonite at different pHs. When this Mt dispersion was added to a starch containing PEG, CA gave slightly reduced plastic viscosity and showed a potential to further reduce the WVTR.

Effects of phytoestrogens on sex reversal of Nile tilapia (Oreochromis niloticus) larvae fed diets treated with 17α-Methyltestosterone

Two consecutive experiments were carried out to investigate the effects of phytoestrogens on sex reversal of Nile tilapia (Oreochromis niloticus) larvae. Experiment 1 investigated the effects of phytoestrogen contents of soybean meal (SBM) on sex ratio. Nile tilapia larvae (0.01g/fish) were fed isonitrogenous (35% crude protein) and isocaloric (19MJ/kg) diets containing fishmeal (FM) or SBM as protein sources, each with or without supplementation of 17α-methyltestosterone (MT) at 60mg/kg diet, for 28days. The control, SBM-based diet produced significantly higher percentage of females (77%) than the FM-based diet (52%). The addition of MT to SBM resulted in a significant reduction in percentage of females (31%), however, this percentage was significantly higher than that produced by FM-based diet treated with MT (only 3% females).The second experiment was carried out to verify the results of the first experiment by investigating the effects of different concentrations of pure, crystalline genistein and daidzein (the major phytoestrogens present in soybean) on sex reversal of Nile tilapia larvae fed on a FM-based diet treated with MT. The same FM-based diet used in experiment 1 was used in experiment 2, and treated with MT, and then divided into equal portions treated with genistein or daidzein at 0, 10, 20 and 30mg/kg diet. The diets were fed to Nile tilapia larvae for 28days. The control, hormone-free diet produced almost equal ratio of females and males (0.96:1). The addition of MT significantly increased the percentage of males. The percent of males was sharply reduced with increasing daidzein and genistein concentrations in the diets. These results revealed that phytoestrogen contents of SBM have estrogenic effects on Nile tilapia larvae. Therefore, soybean meal and other plant protein sources containing high levels of phytoestrogens should be avoided as protein sources for Nile tilapia larvae during sex reversal treatments.

Addition of MT, D16S10, D16S4, and D16S91 to the linkage map within 16q12.1-q22.1

A 10-point genetic linkage map of the region 16q12.1 to 16q22.1 has been constructed using the CEPH reference families. Four loci, MT, D16S10, D16S91, and D16S4, not previously localized on a multipoint linkage map, were incorporated on the map presented here. The order of loci was cen- D16S39-MT, D16S65-D16S10-FRA16B-D16S38, D16S4, D16S91, D16S46-D16S47-HP-qter. The interval between D16S10 and 4D16S38 is 3.1 cM in males and 2.3 cM in females, and contains FRA16B. The cloning strategy for FRA16B will now be based on YAC walking from D16S10 and D16S38. The location of FRA16B between D16S10 and D16S38 provides a physical reference point for the multipoint linkage map on the short arm of chromosome 16.

Effects of 17-?-methultestosterone and 17-?-oestradiol on intestinal transport and absorption ofl-(14C)-leucine in vitro in rainbow trout (Salmo gairdneri)

The effects of 17-α-methyltesterone (MT) and 17-β-oestradiol (E2) on transport and absorption ofl-(14C)-leucine, were studiedin vitro using everted gut sacs of rainbow trout (Salmo gairdneri), incubated at 14°C for 60 min. Hormone administration was carried out either by intramuscular injection (200 μg/100 g·day) on alternate days for 10 days, or by direct addition (200 μg/ml) to incubation media containing sacs from untreated fish (MT+; E2+). Addition of MT to incubation media significantly increased the serosal leucine increase (SLI) and mucosal absorption after 20 min of incubation (Table 1), but did not influence the overall ability of the intestine to accumulate radioleucine (Fig. 1). By contrast, MT injection elicited significant increases in overall intestinal accumulation of radioleucine (Fig. 2) and SLI, but was without effect on mucosal absorption (Table 2). Both MT+ and MT injection resulted in regional variations of radioleucine accumulation along the intestine, being higher in the midgut of the MT+ group (Fig. 1), and higher in the hindgut of the MT injected group (Fig. 2). Injection of E2 significantly increased midgut accumulation (Fig. 2) and SLI, but was without effect on mucosal absorption (Table 2). Addition of E2 into the incubation media however, was without effect on any of the parameters studied, nor were regional variations of radioleucine accumulation detected in any group receiving E2 treatment. These results suggest that steroid-induced growth promotion in fish may be partly a consequence of enhanced efficiency of intestinal function.