The transport of organic contaminants in groundwater might be greatly affected by coexistence of dissolved organic matter (DOM) from different sources. In this study, the effects of endogenous and ...exogenous DOMs (referred to as DOMen and DOMex, respectively) on sorption behavior of bisphenol A (BPA) onto two reference soils were investigated by batch experiments and microscopic characterization. The results showed that BPA sorption onto soils was dominated by soil organic matter content and affected by DOM properties. The effect of DOMen on BPA sorption was also related to the inorganic components of the two soils. The decrease of organic matter content reduced the sorption capacity of fluvo-aquic soil. However, because the content of available inorganic components in black soil was high, after removing DOMen, more inorganic sites were exposed to increase the sorption capacity. In addition, DOMen could form complexes with BPA in solution, thus the removal of DOMen promoted BPA sorption onto black soil. Under the experimental conditions, contribution of DOMex to the total sorption of BPA onto both soils was not more than 30%. Results of dialysis experiments and soil sorption experiments indicated that effects of coexisting DOMex on BPA sorption was related to the affinity of DOMex to soils and complexation of BPA and DOMex. Since the affinity of DOMex to fluvo-aquic soil was relatively low, the complex of BPA and DOMex in solution was the main inhibition mechanism for BPA sorption. For black soil, higher complexation proportion of BPA with DOMex adsorbed onto soil which promoted BPA sorption onto soil. The findings are of significance for understanding the co-migration of DOM with BPA through soils.
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•Removal of endogenous DOM could expose available inorganic sorption sites on soil.•Distribution of exogenous DOM-BPA complexes determined BPA sorption to soils.•Affinity between exogenous DOM and soil was the main factor affecting BPA sorption.•Complexation of BPA to DOMex in solution inhibited sorption onto fluvo-aquic soil.•DOMex sorbed onto black soil, and promoted co-sorption of BPA.
Natural colloids can influence the binding mechanisms between nano-hydroxyapatite (nHAP) and Cd(II). In this study, the effects of organic and inorganic natural colloids on Cd(II) sorption onto nHAP ...were compared. Different experimental approaches combined with the additivity model and the Extended-Derjaguin-Landau-Verwey–Overbeek model were used to quantify the distribution of Cd(II) in the systems of nHAP and natural colloid, and the interaction energy between particles. The results showed that both fulvic acid (FA) and montmorillonite colloid (MONT) had the promotion and inhibition effects on Cd(II) sorption onto nHAP. Coexistence of FA or MONT could stabilize nHAP particles. FA could adsorb onto nHAP particle surface via carboxylic and phenolic groups, which increased nHAP electronegativity and formed steric resistance effect. Coexistence of MONT mainly increased nHAP electronegativity. These effects prevented the reduction of the specific surface area of nHAP particles and increased the Cd(II) sorption onto nHAP. However, the inhibition effect on Cd(II) sorption was enhanced with increasing concentration of FA or MONT because more soluble FA-Cd or suspended MONT-Cd complexes formed in the system. In nHAP-FA-Cd systems, the Cd(II) sorption onto FA was well predicted but that onto solid phase was underestimated by the additivity model. In nHAP-MONT-Cd systems, Cd(II) sorbed onto mixtures of nHAP and MONT was well described by the additive model. The findings of this study can help to understand the fate of Cd(II) in natural water and soil.
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•Binding of FA to nHAP prevents its aggregation and increases its electronegativity.•Montmorillonite increases Cd sorption onto nHAP mainly due to electrostatic forces.•Soluble FA-Cd complex and suspended montmorillonite-Cd inhibit Cd sorption onto nHAP.•The additive model applied in nHAP-FA mixtures underestimates Cd sorption onto nHAP.•Cd adsorbed onto nHAP-montmorillonite mixtures is well described in additive model.
Production of vanillin from natural green vanilla pods was carried out by enzyme-assisted extraction combined with pre-freezing and thawing. In the first step the green vanilla pods were pre-frozen ...and then thawed to destroy cellular compartmentation. In the second step pectinase from Aspergillus niger was used to hydrolyze the pectin between the glucovanillin substrate and β-glucosidase. Four main variables, including enzyme amount, reaction temperature, time and pH, which were of significance for the vanillin content were studied and a central composite design (CCD) based on the results of a single-factor tests was used. Response surface methodology based on CCD was employed to optimize the combination of enzyme amount, reaction temperature, time, and pH for maximum vanillin production. This resulted in the optimal condition in regards of the enzyme amount, reaction temperature, time, and pH at 84.2 mg, 49.5 °C, 7.1 h, and 4.2, respectively. Under the optimal condition, the experimental yield of vanillin was 4.63% ± 0.11% (dwb), which was in good agreement with the value predicted by the model. Compared to the traditional curing process (1.98%) and viscozyme extract (2.36%), the optimized method for the vanillin production significantly increased the yield by 133.85% and 96%, respectively.
Support vector machine(SVM) is an effective tool in deal with small sample, nonlinear and high dimension classification problems. In this paper, an improved pre-treatment binary-tree SVM is proposed ...to solve fault diagnosis. Furthermore an ensemble method is presented to establish ensemble SVM. Here the improved SVM is used as weak learning machine. The new ensemble SVM can improve the performance of single binary-tree SVM.At the end, the new algorithm is applied to fault diagnosis of blast furnace faults and the Tennessee Eastman process(TEP). The experiments results show that the improved binary-tree SVM algorithm has an excellent performance on diagnosis speed and accuracy.
CYP450 plays an essential role in the development and growth of the fruits of Siraitia grosvenorii. However, little is known about the SgCYP450-4 gene in S. grosvenorii. Here, based on transcriptome ...data, a full-length c DNA sequence of SgCYP450-4 was cloned by reverse transcriptasepolymerase chain reaction(RT-PCR) and rapid-amplification of c DNA ends(RACE) strategies. SgCYP450-4 is 1677 bp in length(Gen Bank accession No. AEM42985.1) and contains a complete open reading frame(ORF) of 1422 bp. The deduced protein was composed of 473 amino acids, the molecular weight is 54.01 kDa, the theoretical isoelectric point(PI) is 8.8, and the protein was predicted to possess cytochrome P450 domains. SgCYP450-4 gene was highly expressed in root, diploid fruit and fruit treated with hormone and pollination. At 10 days after treatment with pollination and hormones, the expression of SgCYP450-4had the highest level and then decreased over time, which was consistent with the development of fruits of S.Grosvenorii. Hormonal treatment could significantly induce the expression of SgCYP450-4. These results provide a reference for regulation of fruit development and the use of parthenocarpy to generate seedless fruit, and provide a scientific basis for the production of growth regulator application agents.
Soil-bound heavy metals are of great concern for human health due to the potential exposure via food chain transfer. In the present study, the occurrence, the bioavailability and the soil-to-crop ...transfer of heavy metals in farmland soils were investigated based on data from two agricultural areas, i.e. Sihui and Shunde in South China. Six heavy metals (As, Cu, Hg, Mn, Ni and Pb) were quantified in the farmland soils. The mean single pollution level indices (PI) were all lower than 1 except for Hg in soils from Shunde (PI = 1.51 ± 0.46), suggesting the farmland soils were within clean and slightly polluted by heavy metals. As, Cu, Ni and Pb were found to be mostly present in the non-bioavailable form. The majority of Hg was considered potentially bioavailable, and Mn was found to be largely bioavailable. Soil pH was an important factor influencing bioavailability of soil-bound heavy metals. The concentrations of heavy metals in vegetables from Sihui and Shunde were within the food hygiene standards, while the rice grain from Sihui was polluted by Pb (PI = 10.3 ± 23.4). Total soil concentrations of heavy metals were not correlated to their corresponding crop concentrations, instead, significant correlations were observed for bioavailable concentrations in soil. The results supported the notion that the bioavailability of the investigated heavy metals in the soil was largely responsible for their crop uptake. The soil-to-crop transfer factors based on bioavailable concentrations suggested that Cu, As and Hg in soils of the study area had greater tendency to be accumulated in the vegetables than other heavy metals, calling for further human health assessment by consuming the contaminated crops.
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•The farmland soil was slightly polluted by Hg in the studied area in South China.•Soil pH was a key factor influencing bioavailability of soil-bound metals.•Rice grain from Sihui was heavily polluted by Pb.•Bioavailable fraction of heavy metals better predicted their crop concentrations.•Cu, As and Hg were accumulated more in vegetables than other metals.
Bioavailability-based soil-to-crop transfer factors suggested that Cu, As and Hg in farmland soils from South China had higher tendency to be accumulated in the vegetables than other heavy metals.
In the past decade, the most prevalent norovirus genotype causing viral gastroenteritis outbreaks worldwide, including China, has been GII.4. In winter 2014-15, norovirus outbreaks in Guangdong, ...China, increased. Sequence analysis indicated that 82% of the outbreaks were caused by a norovirus GII.17 variant.
Understanding the dynamics of muscle transcriptome during development and between breeds differing in muscle growth is necessary to uncover the complex mechanism underlying muscle development. ...Herein, we present the first transcriptome-wide longissimus dorsi muscle development research concerning Lantang (LT, obese) and Landrace (LR, lean) pig breeds during 10 time-points from 35 days-post-coitus (dpc) to 180 days-post-natum (dpn) using Solexa/Illumina's Genome Analyzer. The data demonstrated that myogenesis was almost completed before 77 dpc, but the muscle phenotypes were still changed from 77 dpc to 28 dpn. Comparative analysis of the two breeds suggested that myogenesis started earlier but progressed more slowly in LT than in LR, the stages ranging from 49 dpc to 77 dpc are critical for formation of different muscle phenotypes. 595 differentially expressed myogenesis genes were identified, and their roles in myogenesis were discussed. Furthermore, GSK3B, IKBKB, ACVR1, ITGA and STMN1 might contribute to later myogenesis and more muscle fibers in LR than LT. Some myogenesis inhibitors (ID1, ID2, CABIN1, MSTN, SMAD4, CTNNA1, NOTCH2, GPC3 and HMOX1) were higher expressed in LT than in LR, which might contribute to more slow muscle differentiation in LT than in LR. We also identified several genes which might contribute to intramuscular adipose differentiation. Most important, we further proposed a novel model in which MyoD and MEF2A controls the balance between intramuscular adipogenesis and myogenesis by regulating CEBP family; Myf5 and MEF2C are essential during the whole myogenesis process while MEF2D affects muscle growth and maturation. The MRFs and MEF2 families are also critical for the phenotypic differences between the two pig breeds. Overall, this study contributes to elucidating the mechanism underlying muscle development, which could provide valuable information for pig meat quality improvement. The raw data have been submitted to Gene Expression Omnibus (GEO) under series GSE25406.
MicroRNAs (miRNAs) are a large class of tiny non-coding RNAs (approximately 22-24 nt) that regulate diverse biological processes at the posttranscriptional level by controlling mRNA stability or ...translation. As a molecular switch, the canonical Wnt/beta-catenin signaling pathway should be suppressed during the adipogenesis; However, activation of this pathway leads to the inhibition of lipid depots formation. The aim of our studies was to identify miRNAs that might be involved in adipogenesis by modulating WNT signaling pathway. Here we established two types of cell model, activation and repression of WNT signaling, and investigated the expression profile of microRNAs using microarray assay.
The high throughput microarray data revealed 18 miRNAs that might promote adipogenesis by repressing WNT signaling: miR-210, miR-148a, miR-194, miR-322 etc. Meanwhile, we also identified 29 miRNAs that might have negative effect on adipogenesis by activating WNT signaling: miR-344, miR-27 and miR-181 etc. The targets of these miRNAs were also analysed by bioinformatics. To validate the predicted targets and the potential functions of these identified miRNAs, the mimics of miR-210 were transfected into 3T3-L1 cells and enlarged cells with distinct lipid droplets were observed; Meanwhile, transfection with the inhibitor of miR-210 could markedly decrease differentiation-specific factors at the transcription level, which suggested the specific role of miR-210 in promoting adipogenesis. Tcf7l2, the predicted target of miR-210, is a transcription factor triggering the downstream responsive genes of WNT signaling, was blocked at transcription level. Furthermore, the activity of luciferase reporter bearing Tcf7l2 mRNA 3' UTR was decreased after co-transfection with miR-210 in HEK-293FT cells. Last but not least, the protein expression level of beta-catenin was increased in the lithium (LiCl) treated 3T3-L1 cells after transfection with miR-210. These findings suggested that miR-210 could promote adipogenesis by repressing WNT signaling through targeting Tcf7l2.
The results suggest the presence of miRNAs in two cell models, providing insights into WNT pathway-specific miRNAs that can be further characterized for their potential roles in adipogenesis. To our knowledge, present study represents the first attempt to unveil the profile of miRNAs involved in adipogenesis by modulating WNT signaling pathway, which contributed to deeper investigation of the mechanism of adipogenesis.
The alkaloids of Narcissus tazetta L. var. Chinensis Roem (Amaryllidaceae) have antitumor and antiviral activities. However, the immunopharmacological effects of one of its constituents, ...pseudolycorine chloride (PLY), have not been reported yet.
We evaluated the effect of PLY on myeloid-derived suppressor cells (MDSCs) expansion and differentiation into monocyte-like MDSCs (M-MDSCs) and examined whether PLY alleviates Th17 cell-mediated experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS).
In vitro, MDSCs were treated with PLY (0.67, 2 and 6 μM) or solcitinib (10 μM, positive control) for 48 or 96 h, and their proliferation, expansion, and differentiation into M-MDSCs were examined by flow cytometry. Myelin oligodendrocyte glycoprotein (MOG
35-55
) was used to induce EAE in female C57BL/6 mice, and the mice were treated with 40 mg/kg/d PLY or 1 mg/kg/d FK-506 (tacrolimus, positive control) for 21 days. Inflammatory infiltration, spinal cord demyelination, and MDSCs and Th17 cells infiltration into the spinal cord were examined using haematoxylin and eosin staining, Luxol fast blue staining, and immunofluorescence, respectively.
In vitro, PLY (IC50/24 h = 6.18 μM) significantly inhibited IL-6 and GM-CSF-induced MDSCs proliferation, expansion and differentiation into M-MDSCs at all concentrations used. However, these concentrations did not show cytotoxicity. In mice, PLY (40 mg/kg) treatment alleviated EAE and inhibited inflammatory infiltration, demyelination, and MDSCs and Th17 cells infiltration into the spinal cord.
PLY may be an excellent candidate for the treatment of MS and other autoimmune diseases.
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