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An efficient and operationally simple method for the synthesis of ß-keto sulfones through the BF3·OEt2-promoted reaction of alkynes and sodium sulfinates is developed. With its facile and selective access to the targets, it features good functional group compatibility, mild conditions, easily available starting materials, and good yields. Notably, the reaction does not require metal catalysts or chemical reagents with pungent odors.
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How to effectively improve the poor interfacial adhesion between polylactic acid/poly(butylene adipate-co-terephthalate) (PLA/PBAT) matrix and thermoplastic starch (TPS) is still a challenge. Therefore, this work aims to introduce a convenient method to enhance the performance of PLA/PBAT/TPS blend by melt reactive extrusion. Here, using 4,4'-methylene-bis(N,N-diglycidyl-aniline) (MBDG) containing four epoxy groups as a reactive compatibilizer, and respectively using 1-methylimidazole (MI) or triethylenediamine (TD) as a catalyzer, serial PLA/PBAT/TPS ternary bio-composites are successfully prepared via melt reactive extrusion. The results showed that, under the catalysis of organic base, especially MI, the epoxy groups of MBDG can effectively react with hydroxyl and carboxyl groups of PLA/PBAT and hydroxyl groups in TPS to form chain-expanded and cross-linked structures. The tensile strength of the composites is increased by 20.0 % from 21.1 MPa, and the elongation at break is increased by 182.4 % from 17.6 % owing to the chain extension and the forming of cross-linked structures. The molecular weight, thermal stability, crystallinity, and surface hydrophobicity of the materials are gradually improved with the increase of MBDG content. The melt fluidity of the composites is also improved due to the enhancement of compatibility. The obtained PLA/PBAT/TPS materials have the potential to be green plastic products with good properties.
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Alcenos , Resinas Epóxi , Ácidos Ftálicos , Poliésteres , Adipatos , AmidoRESUMO
Gastrointestinal dysfunction is manifested as digestive symptoms. Clinically, Zusanli (ST36) is crucial in the acupoint prescriptions of acupuncture no matter which type of the disease is differentiated in traditional Chinese medicine, but the underlying mechanism remains to be explored. Aiming to summarize the current status of the researches in terms of ameliorating gastrointestinal mucosal damage and regulating gastrointestinal motility disorders, we systematically reviewed the basic researches on the intervention with electroacupuncture (EA) at "ST36" in treatment of the diseases related to gastrointestinal dysfunction in the past 5 years, after searching the articles from Chinese and English databases. The results suggest that EA at ST36 may regulate the local gastrointestinal inflammation, oxidative stress and immune microenvironment to relieve gastrointestinal mucosal damage and adjust gastrointestinal motility disorders by means of modulating the central and peripheral nerve signaling as well as the function of mast cells and Cajal interstitial cells.
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Terapia por Acupuntura , Eletroacupuntura , Gastroenteropatias , Ratos , Animais , Humanos , Eletroacupuntura/métodos , Ratos Sprague-Dawley , Pontos de Acupuntura , Gastroenteropatias/genética , Gastroenteropatias/terapiaRESUMO
Strong relationships have been found between appendicular lean mass (ALM) and bone mineral density (BMD). It may be due to a shared genetic basis, termed pleiotropy. By leveraging the pleiotropy with BMD, the aim of this study was to detect more potential genetic variants for ALM. Using the conditional false discovery rate (cFDR) methodology, a combined analysis of the summary statistics of two large independent genome wide association studies (GWAS) of ALM (n = 73,420) and BMD (n = 10,414) was conducted. Strong pleiotropic enrichment and 26 novel potential pleiotropic SNPs were found for ALM and BMD. We identified 156 SNPs for ALM (cFDR <0.05), of which 74 were replicates of previous GWASs and 82 were novel SNPs potentially-associated with ALM. Eleven genes annotated by 31 novel SNPs (13 pleiotropic and 18 ALM specific) were partially validated in a gene expression assay. Functional enrichment analysis indicated that genes corresponding to the novel potential SNPs were enriched in GO terms and/or KEGG pathways that played important roles in muscle development and/or BMD metabolism (adjP <0.05). In protein-protein interaction analysis, rich interactions were demonstrated among the proteins produced by the corresponding genes. In conclusion, the present study, as in other recent studies we have conducted, demonstrated superior efficiency and reliability of the cFDR methodology for enhanced detection of trait-associated genetic variants. Our findings shed novel insight into the genetic variability of ALM in addition to the shared genetic basis underlying ALM and BMD.
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Peso Corporal/genética , Densidade Óssea/genética , Polimorfismo de Nucleotídeo Único , Feminino , Estudo de Associação Genômica Ampla , Humanos , MasculinoRESUMO
Remote sensing has been used as an important means of estimating crop production, especially for the estimation of crop yield in the middle and late growth period. In order to further improve the accuracy of estimating winter wheat yield through remote sensing, this study analyzed the quantitative relationship between satellite remote sensing variables obtained from HJ-CCD images and the winter wheat yield, and used the partial least square (PLS) algorithm to construct and validate the multivariate remote sensing models of estimating the yield. The research showed a close relationship between yield and most remote sensing variables. Significant multiple correlations were also recorded between most remote sensing variables. The optimal principal components numbers of PLS models used to estimate yield were 4. Green normalized difference vegetation index (GNDVI), optimized soil-adjusted vegetation index (OSAVI), normalized difference vegetation index (NDVI) and plant senescence reflectance index (PSRI) were sensitive variables for yield remote sensing estimation. Through model development and model validation evaluation, the yield estimation model's coefficients of determination (R2) were 0.81 and 0.74 respectively. The root mean square error (RMSE) were 693.9 kg ha-1 and 786.5 kg ha-1. It showed that the PLS algorithm model estimates the yield better than the linear regression (LR) and principal components analysis (PCA) algorithms. The estimation accuracy was improved by more than 20% than the LR algorithm, and was 13% higher than the PCA algorithm. The results could provide an effective way to improve the estimation accuracy of winter wheat yield by remote sensing, and was conducive to large-area application and promotion.
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Normalized difference vegetation index (NDVI) is one of the most important vegetation indices in crop remote sensing. It features a simple, fast, and non-destructive method and has been widely used in remote monitoring of crop growing status. Beer-Lambert law is widely used in calculating crop leaf area index (LAI), however, it is time-consuming detection and low in output. Our objective was to improve the accuracy of monitoring LAI through remote sensing by integrating NDVI and Beer-Lambert law. In this study, the Beer-Lambert law was firstly modified to construct a monitoring model with NDVI as the independent variable. Secondly, experimental data of wheat from different years and various plant types (erectophile, planophile and middle types) was used to validate the modified model. The results showed that at 130 DAS (days after sowing), the differences in NDVI, leaf area index (LAI) and extinction coefficient (k) of the three plant types with significantly different leaf orientation values (LOVs) reached the maximum. The NDVI of the planophile-type wheat reached saturation earlier than that of the middle and erectophile types. The undetermined parameters of the model (LAI = -ln (a1 × NDVI + b1)/(a2 × NDVI + b2)) were related to the plant type of wheat. For the erectophile-type cultivars (LOV ≥ 60°), the parameters for the modified model were, a1 = 0.306, a2 = -0.534, b1 = -0.065, and b2 = 0.541. For the middle-type cultivars (30° < LOV < 60°), the parameters were, a1 = 0.392, a2 = -0.881, b1 = 0.028, and b2 = 0.845. And for the planophile-type cultivars (LOV ≤ 30°), those parameters were, a1 = 0.596, a2 = -1.306, b1 = 0.014, and b2 = 1.130. Verification proved that the modified model based on integrating NDVI and Beer-Lambert law was better than Beer-Lambert law model only or NDVI-LAI direct model only. It was feasible to quantitatively monitor the LAI of different plant-type wheat by integrating NDVI and Beer-Lambert law, especially for erectophile-type wheat (R2 = 0.905, RMSE = 0.36, RE = 0.10). The monitoring model proposed in this study can accurately reflect the dynamic changes of plant canopy structure parameters, and provides a novel method for determining plant LAI.
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Agricultura/métodos , Produtos Agrícolas/fisiologia , Folhas de Planta/fisiologia , Triticum/classificação , Triticum/fisiologia , Produtos Agrícolas/metabolismo , Folhas de Planta/metabolismo , Triticum/metabolismoRESUMO
BACKGROUND We aimed to identify pivotal genes and pathways involved in pancreatic ductal adenocarcinoma (PDAC), and explore possible molecular markers for the early diagnosis of the disease. MATERIAL AND METHODS The array data of GSE74629, including 34 PDAC samples and 16 healthy samples, was downloaded from GEO (Gene Expression Omnibus) database. Then, the DEGs (differentially expressed genes) in PDAC samples were compared with healthy samples using limma (linear models for microarray). Gene functional interaction networks were analyzed with Cytoscape and ReactomeFIViz. PPI networks were constructed with Cytoscape software. In addition, PPI (protein-protein interaction) network clustering modules were analyzed with ClusterONE, and the KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analyses for modules were performed. RESULTS A total of 630 upregulated and 1,002 downregulated DEGs were identified in PDAC samples compared with healthy samples. Some ribosomal protein genes with higher average correlation in module 0 were enriched in the ribosome pathway. NUP107 (nucleoporin 107 kDa) and NUP160 (nucleoporin 160 kDa) were enriched in module 3. HNRNPU (heterogeneous nuclear ribonucleoprotein U) with higher average correlation in module 8 was enriched in the spliceosome pathway. The ribosome pathway and the spliceosome pathway were significantly enriched in cluster 1 and cluster 2, respectively. CONCLUSIONS Ribosomal protein genes Nup170, Nup160, and HNRNPU, and the ribosome pathway as well as the spliceosome pathway may play important roles in PDAC progression. In addition, ribosomal protein genes Nup170, Nup160, and HNRNPU may be used as possible molecular markers for the early diagnosis of the disease.
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Biomarcadores Tumorais/análise , Carcinoma Ductal Pancreático/diagnóstico , Perfilação da Expressão Gênica/métodos , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/genética , Biologia Computacional/métodos , Redes de Comunicação de Computadores , Bases de Dados Genéticas , Regulação para Baixo , Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Mapas de Interação de Proteínas , Transdução de Sinais/genética , Software , Regulação para CimaRESUMO
A simple, accurate and highly sensitive analytical method was developed in this study for determining the residues and dissipation dynamics of mepiquat chloride in soil and cotton crops (including plant and seed). The samples in this method were directly extracted with methanol-ammonium acetate solution and followed by analysis of high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The intra-day and inter-day recoveries of mepiquat chloride were in the range of 76.58-98.87 percent and 73.48-104.7 percent with relative standard deviations (RSDs) of 0.89-5.04 percent and 3.84-10.7 percent, respectively. The limit of quantification (LOQ) was 0.05mgkg(-1) for soil and 0.1mgkg(-1) for cotton plant and seed. The half-life of mepiquat chloride in cotton plants and in soil was 2.51-3.85 days and 7.56-10.50 days, respectively. The final residues of mepiquat chloride in all cotton seeds were below the MRLs of EU (5mgkg(-1)), Japan and America (2mgkg(-1)) over 14 days after the last spraying, and were below 1mgkg(-1) (the MRLs set by Argentina and Australia) over 21 days after the last spraying at recommended dosage. The final residues in soil were below the LOD (0.01mgkg(-1)) over 21 days after the last spraying.
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Gossypium/metabolismo , Piperidinas/química , Reguladores de Crescimento de Plantas/química , Poluentes do Solo/química , Solo/análise , Cromatografia Líquida de Alta Pressão/métodos , Meia-Vida , Limite de Detecção , Espectrometria de Massas em Tandem/métodosRESUMO
Polyacrylate (PAANa) and polyethylenimine (PEI) were used as complexing agents to combine with nickel ions. This complexation solution was transferred to the ultrafiltration cell and the separation by polyethersulfone (PES) ultrafiltration membranes was carried out under the pressure of 0.1 MPa. Effects of solution pH and polymer/Ni2+ mass ratio on nickel removal were investigated. The complex reaction equilibrium constants were calculated according to Langmuir isotherm model. Effects of concentration time on nickel removal and membrane flux were also studied. With PAANa as a polymer, the removal rate of nickel went the highest to 99.5% at pH 8 with PAANa/Ni2+ ratio of 5. When PEI was used, the removal rate of nickel ions went highest to 93.0% at pH 7 with PEI/Ni2+ ratio of 5. Best-fit complexation equilibrium constants at different pH values showed that pH 7 was most beneficial to the complex reaction. In addition, the number of nickel ions bound to a single monomer complexing agent increased with increase of pH value. During 12 h ultrafiltration process, the decline of membrane flux was less than 10% with PAANa as the complexing agent, while the membrane flux remains the same when PEI was used. The removal rates of Ni2+ kept constant with both complexing agents. Results showed that complexation-ultrafiltration can effectively remove nickel from aqueous solution at appropriate conditions.
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Níquel/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Resinas Acrílicas/química , Simulação por Computador , Membranas Artificiais , Polietilenoimina/química , Ultrafiltração/métodosRESUMO
The sudangrass (Sorghum sudanense) and ryegrass (Lolium multi florum L.) rotation is a new type of cropping system, which has developed rapidly in recent years in the south of China. The contents of nutritional elements for forage grass in the sudangrass and ryegrass rotation system were determined by ICP-AES. The results showed that there were abundant and essential nutritional elements for animals in sudangrass and ryegrass. The contents of P, K, Ca, Mg, S, Fe, B, Cu, Zn and Mn for sudangrass were 0.20% -0.29%, 1.94%-2.57%, 0.62%-0.97%, 0.39%-0.69%, 0.12%-0.18%, 108.35-180.12, 3.04-5.96, 6.17-10.02, 20.37-31.36 and 46.80-101.29 mg x kg(-1), respectively. The contents of P, K, Ca, Mg, S, Fe, B, Cu, Zn, Mn for ryegrass were 0.39%-0.70%, 3.77%-5.07%, 0.61%-0.84%, 0.28% -0.47%, 0.32%-0.41%, 291.65- 632.20, 2.13-3.23, 13.29-15.19, 30.73-42.98 and 92.08-156.04 mg x kg(-1), respectively, and there were differences between various periods in nutritional elements in the two forage grasses. The application of ICP-AES could reflect fast and efficiently the content of nutritional elements for forage grass as animals feed.
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Lolium/química , Sorghum/química , Ração Animal , China , Valor Nutritivo , Espectrofotometria AtômicaRESUMO
Liver regeneration is a complex process that involves a multitude of cellular functions, including primarily cell proliferation, apoptosis, inflammation, and metabolism. A number of signaling pathways that control these processes have been identified, and cross communication between them by direct protein-protein interactions has been shown to be crucial in orchestrating liver regeneration. Previously, we have identified a group of transcription factors capable of regulating liver cell growth and that may be involved in liver cancer development. The expression of some of their mouse counterpart genes was altered dramatically after liver injury and regeneration induced by CCl(4) in mice. In an effort to elucidate the molecular basis for liver regeneration through protein-protein interactions (PPI), a matrix mating Y2H approach was produced to generate a PPI network between a set of 32 regulatory proteins. Sixty-four interactions were identified, including 4 that had been identified previously. Ten of the interactions were further confirmed with GST pull-down and coimmunoprecipitation assays. Information provided by this PPI network may shed further light on the molecular mechanisms that regulate liver regeneration at the protein interaction level and ultimately identify regulatory factors that may serve as candidate drug targets for the treatment of liver diseases.
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Proliferação de Células , Fatores de Transcrição/metabolismo , DNA Complementar , Escherichia coli/metabolismo , Humanos , Fígado/citologia , Fígado/metabolismo , Ligação ProteicaRESUMO
OBJECTIVE: To explore the effect of serum from partial hepatectomy (PH) rat and hepatocyte growth factor (HGF) on expression of albumin and AFP of bone marrow cells. METHODS: The bone marrow mono-nucleated cells were separated from SD rats and cultured in three groups: (1) The medium only group as control was added normal fetal bovine serum; (2) Rat hepatic injury serum group (was added 15% rat serum from 2-AAF+PH model); (3) HGF group (HGF 20 ng/ml). The role of these factors was determined by RT-PCR, immunohistochemistry (IHC) and Western blot, using AFP and albumin as special hepatocytic markers. RESULTS: By immunohistochemical staining and Western blot, the fresh bone marrow cells were AFP-negative, same as the cells cultured with medium only group. While bone marrow cells, co-cultured with rat hepatic injury serum or HGF at day 10 and 20, expressed AFP protein. AFP mRNA expression could be found in bone marrow cells after 10 and 20 days cultured with rat hepatic injury serum or HGF, but not in fresh bone marrow cells and bone marrow cells cultured with medium only. Albumin mRNA expression was weak in fresh bone marrow cell and increased in groups 2 and 3. CONCLUSION: The rat hepatic injury serum or HGF could stimulate the expression of AFP protein and it's mRNA of bone marrow cells. Also they can stimulate albumin mRNA expression. It seems that, in bone marrow, there is a kind of cells so called bone marrow derived liver stem cell which can express albumin mRNA in a weak style.