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1.
J Chem Inf Model ; 64(12): 4863-4876, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38836743

RESUMEN

With recent large-scale applications and validations, the relative binding free energy (RBFE) calculated using alchemical free energy methods has been proven to be an accurate measure to probe the binding of small-molecule drug candidates. On the other hand, given the flexibility of peptides, it is of great interest to find out whether sufficient sampling could be achieved within the typical time scale of such calculation, and a similar level of accuracy could be reached for peptide drugs. However, the systematic evaluation of such calculations on protein-peptide systems has been less reported. Most reported studies of peptides were restricted to a limited number of data points or lacking experimental support. To demonstrate the applicability of the alchemical free energy method for protein-peptide systems in a typical real-world drug discovery project, we report an application of the thermodynamic integration (TI) method to the RBFE calculation of ghrelin receptor and its peptide agonists. Along with the calculation, the synthesis and in vitro EC50 activity of relamorelin and 17 new peptide derivatives were also reported. A cost-effective criterion to determine the data collection time was proposed for peptides in the TI simulation. The average of three TI repeats yielded a mean absolute error of 0.98 kcal/mol and Pearson's correlation coefficient (R) of 0.77 against the experimental free energy derived from the in vitro EC50 activity, showing good repeatability of the proposed method and a slightly better agreement than the results obtained from the arbitrary time frames up to 20 ns. Although it is limited by having one target and a deduced binding pose, we hope that this study can add some insights into alchemical free energy calculation of protein-peptide systems, providing theoretical assistance to the development of peptide drugs.


Asunto(s)
Diseño de Fármacos , Péptidos , Receptores de Ghrelina , Termodinámica , Receptores de Ghrelina/agonistas , Receptores de Ghrelina/metabolismo , Péptidos/química , Péptidos/farmacología , Humanos , Unión Proteica , Simulación de Dinámica Molecular , Conformación Proteica
2.
Poult Sci ; 103(4): 103514, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38367471

RESUMEN

The type VI secretion system (T6SS) of avian pathogenic Escherichia coli (APEC) can affect the functions of eukaryotic cells by secreting or injecting effectors. Hemolysin co-regulatory protein (Hcp), one of the markers of the T6SS, is both a structural protein and an effector protein of the T6SS. According to previous studies, mitochondria in eukaryotic cells are targeted by pathogenic bacteria. However, little is known about the regulation of mitochondria in eukaryotic host cells by the T6SS effector protein Hcp of APEC. In our study, DF-1 cells co-incubated with Hcp2a protein for 6 h showed decreased mitochondrial membrane potential, increased Ca2+ concentration, and increased cellular reactive oxygen species (ROS) levels. We therefore conclude that Hcp2a protein causes dysfunction to mitochondria in DF-1 cells. To explain the mechanism that causes mitochondrial dysfunction, we reanalyzed the Hcp2a interaction protein dataset in DF-1 cells, and the Leucine zipper EF-hand-containing transmembrane protein 1 (LETM1), which is associated with mitochondria, was screened. The protein and molecular docking results showed that Hcp2a protein and LETM1 protein have better binding. Finally, subcellular localization results showed that Hcp2a was localized to mitochondria. In summary, Hcp2a effector proteins caused dysfunction to DF-1 cellular mitochondria, and we hypothesize that the interaction of Hcp2a protein with LETM1 protein induces mitochondrial dysfunction and promotes mitochondrial localization of Hcp2a in DF-1 cells.


Asunto(s)
Proteínas Aviares , Enfermedades Mitocondriales , Animales , Escherichia coli , Simulación del Acoplamiento Molecular , Pollos/microbiología , Enfermedades Mitocondriales/veterinaria
3.
Plant Dis ; 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37787685

RESUMEN

Chinese cherry industry has developed rapidly over the past few years, with the planting acreage continuously expanding, from Shandong province to Liaoning, Shaanxi, Hebei, Sichuan etc. Monilia spp. are the most important causal agents of brown rot of cherry, to date, M. fructicola, M. mumecola, and M. fructigena were reported to cause brown rot of cherry in China (Chen et al. 2013; Yin et al. 2014; Liu et al. 2012). In May 2023, fruit of sweet cherry cultivar 'Hongdeng' (Prunus avium L.) with symptoms resembling brown rot were collected from Tongchuan City, Shaanxi Province. Conidia on diseased tissues were spread on a water agar (WA, 1.5% agar and distilled water) medium and isolated with a glass needle under a professional single spore separation microscope (Wuhan Heipu Science and Technology Ltd., Wuhan, China). If no conidia were present, fruit pieces (5 × 5 mm) at the intersection of healthy and diseased tissues were surface sterilized with a sodium hypochlorite solution (1%) for 30 s and washed three times in sterilized water, followed by 75% ethanol for 30 s, then washed three times in sterilized water. After the tissue pieces were dried, they were placed on potato dextrose agar (PDA; 200 g of potato, 20 g of dextrose, and agar at 20 g/L) and incubated at 22 °C for about twenty days to produce spores and then single spore isolation was carried out. Thirty single-spore isolates were obtained and all were morphologically similar. The isolates produced white-gray colonies with even margins and concentric rings of sporogenous mycelium after 3 days incubation, and abundant black-colored stromata on the PDA medium after 15 days of incubation at 22°C. Conidia were one-celled, hyaline, ellipsoid to lemon shape (14.12 × 10.37 µm), with 1-2 germs which is similar to M. yunnanensis on peach. The genomic DNA of the isolates was extracted as described previously (Chi et al. 2009). The pathogen identity was confirmed by multiplex PCR which resulted in a 237bp amplicon, which is diagnostic of M. yunnanensis (Hu et al. 2011). Further sequencing of the internal transcribed spacer (ITS) region 1 and 2 and 5.8S gene (accession number: OR192774) indicated 100% identity with that of M. yunnanensis isolates (accession numbers: MW355895, ON024742). The average daily growth of mycelium on PDA at 22°C was 11.44 mm. Koch's postulates were fulfilled by inoculating 20 mature sweet cherry fruits of cv. 'Van' with mycelial plugs in a drilled hole. After 3 days of incubation at 22℃ in an airtight plastic tray with wet paper, the inoculated fruit developed typical brown rot symptoms. The developing spores on inoculated fruit were confirmed to be M. yunnanensis based on ITS sequence. All control fruit inoculated with a PDA plug remained healthy. M. yunnanensis was first reported as the causal agent of brown rot of peach in China (Hu et al. 2011). Later studies demonstrated that it is also pathogen on other fruits, e.g. hawthorn (Zhao et al. 2013), plum (Yin et al. 2015), apricot (Yin et al. 2017), apple, and pear in China (Zhu et al. 2016). To our knowledge, this is the first report of cherry brown fruit rot caused by M. yunnanensis, indicating the high risk of this species to cherry production, and effective strategies must be taken to prevent the possible control failure in practice.

4.
J Exp Bot ; 74(18): 5635-5652, 2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37368909

RESUMEN

Extensins are hydroxyproline-rich glycoproteins and generally play a structural role in cell wall integrity. In this study, we determined a novel role of tomato (Solanum lycopersicum) SENESCENCE-ASSOCIATED EXTENSIN1 (SAE1) in leaf senescence. Both gain- and loss-of-function analyses suggest that SAE1 plays a positive role in leaf senescence in tomato. Transgenic plants overexpressing SAE1 (SAE1-OX) exhibited premature leaf senescence and enhanced dark-induced senescence, whereas SAE1 knockout (SAE1-KO) plants displayed delayed development-dependent and dark-induced leaf senescence. Heterologous overexpression of SlSAE1 in Arabidopsis also led to premature leaf senescence and enhanced dark-induced senescence. In addition, the SAE1 protein was found to interact with the tomato ubiquitin ligase SlSINA4, and SlSINA4 promoted SAE1 degradation in a ligase-dependent manner when co-expressed in Nicotiana benthamiana leaves, suggesting that SlSINA4 controls SAE1 protein levels via the ubiquitin-proteasome pathway. Introduction of an SlSINA4-overexpression construct into the SAE1-OX tomato plants consistently completely eliminated accumulation of the SAE1 protein and suppressed the phenotypes conferred by overexpression of SAE1. Taken together, our results suggest that the tomato extensin SAE1 plays a positive role in leaf senescence and is regulated by the ubiquitin ligase SINA4.


Asunto(s)
Arabidopsis , Solanum lycopersicum , Ubiquitina/genética , Solanum lycopersicum/genética , Ligasas/genética , Senescencia de la Planta , Arabidopsis/genética , Hojas de la Planta , Regulación de la Expresión Génica de las Plantas
5.
Front Plant Sci ; 14: 1111680, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37223818

RESUMEN

The digestibility of soybean meal can be severely impacted by trypsin inhibitor (TI), one of the most abundant anti-nutritional factors present in soybean seeds. TI can restrain the function of trypsin, a critical enzyme that breaks down proteins in the digestive tract. Soybean accessions with low TI content have been identified. However, it is challenging to breed the low TI trait into elite cultivars due to a lack of molecular markers associated with low TI traits. We identified Kunitz trypsin inhibitor 1 (KTI1, Gm01g095000) and KTI3 (Gm08g341500) as two seed-specific TI genes. Mutant kti1 and kti3 alleles carrying small deletions or insertions within the gene open reading frames were created in the soybean cultivar Glycine max cv. Williams 82 (WM82) using the CRISPR/Cas9-mediated genome editing approach. The KTI content and TI activity both remarkably reduced in kti1/3 mutants compared to the WM82 seeds. There was no significant difference in terms of plant growth or maturity days of kti1/3 transgenic and WM82 plants in greenhouse condition. We further identified a T1 line, #5-26, that carried double homozygous kti1/3 mutant alleles, but not the Cas9 transgene. Based on the sequences of kti1/3 mutant alleles in #5-26, we developed markers to co-select for these mutant alleles by using a gel-electrophoresis-free method. The kti1/3 mutant soybean line and associated selection markers will assist in accelerating the introduction of low TI trait into elite soybean cultivars in the future.

6.
Front Plant Sci ; 14: 1152399, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008499

RESUMEN

The plastic elongation of mesocotyl (MES) and coleoptile (COL), which can be repressed by light exposure, plays a vital role in maize seedling emergence and establishment under adverse environmental conditions. Understanding the molecular mechanisms of light-mediated repression of MES and COL elongation in maize will allow us to develop new strategies for genetic improvement of these two crucial traits in maize. A maize variety, Zheng58, was used to monitor the transcriptome and physiological changes in MES and COL in response to darkness, as well as red, blue, and white light. The elongation of MES and COL was significantly inhibited by light spectral quality in this order: blue light > red light > white light. Physiological analyses revealed that light-mediated inhibition of maize MES and COL elongation was closely related to the dynamics of phytohormones accumulation and lignin deposition in these tissues. In response to light exposure, the levels of indole-3-acetic acid, trans-zeatin, gibberellin 3, and abscisic acid levels significantly decreased in MES and COL; by contrast, the levels of jasmonic acid, salicylic acid, lignin, phenylalanine ammonia-lyase, and peroxidase enzyme activity significantly increased. Transcriptome analysis revealed multiple differentially expressed genes (DEGs) involved in circadian rhythm, phytohormone biosynthesis and signal transduction, cytoskeleton and cell wall organization, lignin biosynthesis, and starch and sucrose metabolism. These DEGs exhibited synergistic and antagonistic interactions, forming a complex network that regulated the light-mediated inhibition of MES and COL elongation. Additionally, gene co-expression network analysis revealed that 49 hub genes in one and 19 hub genes in two modules were significantly associated with the elongation plasticity of COL and MES, respectively. These findings enhance our knowledge of the light-regulated elongation mechanisms of MES and COL, and provide a theoretical foundation for developing elite maize varieties with improved abiotic stress resistance.

7.
Comput Urban Sci ; 3(1): 9, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36874407

RESUMEN

The bath industry has multiple attributes, such as economic, health, and cultural communication. Therefore, exploring this industry's spatial pattern evolution is crucial to forming a healthy and balanced development model. Based on POI (Points of Interest) and population migration data, this paper uses spatial statistics and radial basis function neural network to explore the spatial pattern evolution and influencing factors of the bath industry in mainland China. The results show that: (1) The bath industry presents a strong development pattern in the north, south-northeast, and east-northwest regions and weak development in the rest of the country. As a result, the spatial development of new bath space is more malleable. (2) The input of bathing culture has a guiding role in developing the bath industry. The growth of market demand and related industries has a specific influence on the development of the bath industry. (3) Improving the bath industry's adaptability, integration, and service level are feasible to ensure healthy and balanced development. (4) Bathhouses should improve their service system and risk management control during the pandemic.

8.
Front Plant Sci ; 14: 1111683, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36890894

RESUMEN

CRISPR/Cas9-based genome editing system is a powerful tool for plant genetic improvement. However, the variable efficiency of guide RNA(s) (gRNA) represents a key limiting factor that hampers the broad application of the CRISPR/Cas9 system in crop improvement. Here, we employed the Agrobacterium-mediated transient assays to evaluate the effectiveness of gRNAs for editing genes in Nicotiana benthamiana and soybean. We designed a facile screening system based on indels that can be introduced by CRISPR/Cas9-mediated gene editing. A gRNA binding sequence (23 nucleotides) was inserted into the open reading frame of yellow fluorescent protein (YFP) gene (gRNA-YFP), which disrupted the YFP reading frame and results in no fluorescent signal when it was expressed in plant cells. Transiently co-expression of Cas9 and a gRNA targeting the gRNA-YFP gene in plant cells could restore the YFP reading frame and recover the YFP signals. We evaluated five gRNAs targeting Nicotiana benthamiana and soybean genes and confirmed the reliability of the gRNA screening system. The effective gRNAs targeting NbEDS1, NbWRKY70, GmKTI1, and GmKTI3 had been used to generate transgenic plants and resulted in expected mutations on each gene. While a gRNA targeting NbNDR1 was confirmed to be ineffective in transient assays. This gRNA indeed failed to trigger target gene mutations in stable transgenic plants. Thus, this new transient assay system can be used to validate the effectiveness of gRNAs before generating stable transgenic plants.

9.
Plant Sci ; 331: 111672, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36921631

RESUMEN

Glucose signaling plays an essential role in plant growth, development and stress response. Previous studies have shown that STOREKEEPER (STK) is a new class of DNA binding protein that regulates patatin expression in potato tubers and confers elevated sensitivity to glucose response in Arabidopsis thaliana. However, the biological functions of STK gene in tomato (Solanum lycopersicum) have not been studied. Here, we characterized the tomato SlSTK and determined its role in glucose signaling. The SlSTK protein was localized in the nucleus and the expression of the SlSTK gene was induced by the glucose treatment. Overexpression of SlSTK in tomato enhanced glucose sensitivity, as manifested by reduced seed germination rate and arrested growth at the early seedling stage. In contrast, the SlSTK-knockout plants generated via the clustered regularly interspaced short palindromic repeats (CRISPR) - CRISPR-associated protein 9 (CRISPR-Cas9) technique attenuated the sensitivity to glucose. In addition, SlSTK was ubiquitinated in plant cells and interacted with the tomato ubiquitin ligase SEVEN IN ABSENTIA4 (SlSINA4) that degrades SlSTK in a ligase-dependent manner. Taken together, these results suggest that SlSTK is involved in glucose signaling and its stability is regulated by the ubiquitin ligase SlSINA4.


Asunto(s)
Arabidopsis , Solanum lycopersicum , Solanum lycopersicum/genética , Ubiquitina/metabolismo , Proteínas de Plantas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Plantones , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas
10.
Sci Total Environ ; 865: 161246, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36587686

RESUMEN

The response of vegetation growth to soil moisture varies greatly from space and time under climate change and anthropogenic activities. As an important grain producer in China, the vegetation growth and grain production of North China are constrained by the region's water resources. With the significant increase in vegetation greenness in North China over the last 40 years, it is essential to explore the changes in soil moisture constraints on vegetation growth to water management. However, to what degree vegetation growth responds to soil moisture and how the response varies spatiotemporally in North China remain unclear. In this study, the response patterns of vegetation growth to soil moisture at different depths and the spatiotemporal trend patterns of their relationships were explored thoroughly based on long time series remote sensing data in North China over the past 40 years. The results showed that compared to forests, the growth of grasslands and crops with one maturity per year and two maturity per year in North China was more constrained by soil moisture. Due to the combined effects of climatic conditions and human activities, vegetation growth in North China has been significantly less constrained by soil moisture over the last 40 years. This was especially seen in one maturity per year crop and natural vegetation in Shanxi and central Shandong. However, with the significant increase in temperature, potential evapotranspiration and water demand of the crop, the moisture constraints on vegetation growth in North China have begun to show an increasing trend since the early 2000s, especially for irrigated crop in central and southern North China. These findings highlight a comprehensive understanding of the vegetation response to soil moisture from the time-varying perspective and provide a theoretical basis for water management and appropriate planning of agricultural water use in North China.


Asunto(s)
Agricultura , Suelo , Humanos , Productos Agrícolas , China , Cambio Climático , Agua , Ecosistema
11.
Foods ; 11(14)2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35885356

RESUMEN

Ethanol has great effects on the adsorption of phthalate acid esters (PAEs) on activated carbon (AC), which are usually overlooked and hardly studied. This study investigated the overlooked effects of ethanol on the adsorption of PAEs in alcoholic solutions. The adsorption capacities of dibutyl phthalate (DBP) on AC in solutions with ethanol contents of 30, 50, 70, and 100 v% were only 59%, 43%, 19%, and 10% of that (16.39 mg/g) in water, respectively. The ethanol content increase from 50 v% to 100 v% worsened the adsorption performances significantly with the formation of water-ethanol-DBP clusters (decreasing from 13.99 mg/g to 2.34 mg/g). The molecular dynamics simulation showed that the DBP tended to be distributed farther away from the AC when the ethanol content increased from 0 v% to 100 v% (the average distribution distance increased from 5.25 Å to 15.3 Å). The PAEs with shorter chains were more affected by the presence of ethanol than those with longer chains. Taking DBP as an example, the adsorption capacity of AC in ethanol (0.41 mg/g) is only 2.2% of that in water (18.21 mg/g). The application results in actual Baijiu samples showed that the adsorption of PAEs on AC had important effects on the Baijiu flavors.

12.
Sci Total Environ ; 826: 154104, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35219684

RESUMEN

Irrigation substantially alters land surface temperature (LST) in different regions of the world. Studies have recently focused on quantifying irrigation-induced LST change based on remote sensing technology due to its high spatiotemporal resolution. However, the biophysical mechanisms of irrigation on LST remains poorly understood. Here we first investigated the impact of irrigation on LST during 2003-2012 over the North China Plain (NCP), which is one of the most intensively irrigated areas around the word. We then attributed the mechanisms underlying LST change between adjacent irrigated and non-irrigated croplands based on two surface energy balance-based methods: the Decomposed Temperature Metric (DTM) method and the intrinsic biophysical mechanism (IBM) method. The results indicate that at annual scale, irrigation produce an overall cooling effect over the NCP, with the mean observed LST change of -0.098 K, calculated LST change of -0.096 K for DTM method and -0.165 K for IBM method, respectively. Furthermore, the agreement between the annual observed and calculated LST difference indicate that DTM is a more robust method than IBM in quantifying irrigation-induced LST change over the NCP. The attribution method DTM reveals that components of albedo and emissivity has an average cooling effect of -0.012 K and -0.005 K, respectively, while incoming radiation lead to a weak warming effect of +0.01 K. The enhanced turbulent fluxes of latent heat flux dominate the cooling effect (-0.174 K on average), further offsets the sensible heat flux warming effect (+0.085 K). Another attribution method IBM demonstrates that the annual cooling effect of irrigation is mostly induced by changes in aerodynamic resistance (-0.175 K), whereas the biophysical contributions of albedo (-0.0005 K) and Bowen ratio (+0.001 K) have a negligible impact on LST. This study provides a useful reference for assessing local climate impact of irrigation when implementing environmental protection projects.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , China , Clima , Temperatura
13.
New Phytol ; 234(4): 1507-1520, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35211979

RESUMEN

An essential step in the analysis of single-cell RNA sequencing data is to classify cells into specific cell types using marker genes. In this study, we have developed a machine learning pipeline called single-cell predictive marker (SPmarker) to identify novel cell-type marker genes in the Arabidopsis root. Unlike traditional approaches, our method uses interpretable machine learning models to select marker genes. We have demonstrated that our method can: assign cell types based on cells that were labelled using published methods; project cell types identified by trajectory analysis from one data set to other data sets; and assign cell types based on internal GFP markers. Using SPmarker, we have identified hundreds of new marker genes that were not identified before. As compared to known marker genes, the new marker genes have more orthologous genes identifiable in the corresponding rice single-cell clusters. The new root hair marker genes also include 172 genes with orthologs expressed in root hair cells in five non-Arabidopsis species, which expands the number of marker genes for this cell type by 35-154%. Our results represent a new approach to identifying cell-type marker genes from scRNA-seq data and pave the way for cross-species mapping of scRNA-seq data in plants.


Asunto(s)
Arabidopsis , Análisis de la Célula Individual , Arabidopsis/genética , Biomarcadores , Perfilación de la Expresión Génica/métodos , Aprendizaje Automático , RNA-Seq , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Secuenciación del Exoma
15.
Environ Sci Pollut Res Int ; 29(9): 12777-12796, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32648213

RESUMEN

Rational prediction of future CO2 at the regional level is essential to the carbon emission reduction targets in China. The primary aim of this study is to examine the applicability of an up-to-date forecast algorithm, namely dynamic mode decomposition (DMD), in provincial CO2 emission prediction. The testing results validate the accuracy and application value of the DMD short-run forecast, which may provide method reference for relevant policy formulation and research areas. Moreover, the 2020 provincial economic situation and CO2 emissions in China are projected via DMD. On this basis, the unqualified provinces regarding CO2 emission reduction are identified considering the relative standard and absolute standard, and the corresponding mitigation paths are proposed through decoupling analysis and shadow price calculation. The results indicate that the unqualified provinces include Heilongjiang, Gansu, Shanxi, Hebei, Liaoning, Jilin, Shaanxi, and Inner Mongolia. The open-emission-reduction mechanism should be adopted in the first five provinces; the conservative one should be applied in the other provinces. Graphical abstract.


Asunto(s)
Dióxido de Carbono , Carbono , Carbono/análisis , Dióxido de Carbono/análisis , China , Predicción
16.
Environ Sci Pollut Res Int ; 29(11): 15743-15762, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34636010

RESUMEN

To achieve China's determined contributions by 2030 and establish nationwide carbon emission trading system (ETS) which main participants are sectors, appropriated carbon emission allowance (CEA) allocation among sectors is crucial. In CEA distribution, fairness is primary; and sectoral efficiency is another significant factor. Nevertheless, considering fairness and efficiency while covering various sectors is a challengeable issue. Hence, combined with a new tow-objective data envelopment analysis (DEA) model and genetic algorithm (GA), a novel allocation framework is proposed, i.e., dual level allocation scheme incorporated with GA (DLA-GA). On the basis of evaluating the CO2 emission performance of various sectors in China, the corresponding allocation steps are put forward. Through the value convergence and value repetition tests, the stability and feasibility of DLA-GA are justified. Then, the results of the DLA-GA and grandfathering principle are compared. The research shows that: (1) under the same constraint conditions, the emission right of CO2 is allocated with DLA-GA, which leads to lower cost and higher overall sectoral performance; (2) through utilizing the En-Lorenz and En-Gini coefficients, it has found that higher allocation equity among sectors emerges via DLA-GA;(3) the key reduction sectors have been revealed through emission value estimation. This work may contribute to enrich the methodologies in CEA allocation at different dimensions, and provide some references for policymaker regarding the achievement of 2030 carbon reduction target.


Asunto(s)
Carbono , Gases de Efecto Invernadero , Carbono/análisis , Dióxido de Carbono/análisis , China , Eficiencia , Humanos
17.
Membranes (Basel) ; 11(8)2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34436381

RESUMEN

Blending and heat-treatment play significant roles in adjusting gas separation performances of membranes, especially for incorporating thermally labile polymers into carbon molecular sieve membranes (CMSMs). In this work, cellulose acetate (CA) is introduced into polyimide (PI) as a sacrificial phase to adjust the structure and gas separation performance from polymer to carbon. A novel result is observed that the gas permeability is reduced, even when the immiscible CA phase decomposes and forms pores after heat treatment at 350 °C. After carbonization at 600 °C, the miscible CA has changed without contribution, while the role of the immiscible CA phase has changed from original hindrance to facilitation, the composite-based CMSM at a CA content of 10 wt.% shows highest performances, a H2 permeability of ~5300 Barrer (56% enhancement) with a similar H2/N2 permselectivity of 42. The structural analyses reveal that the chain interactions and phase separation behaviors between CA and PI play critical roles on membrane structures and gas diffusion, and the corresponding phase structural evolutions during heat treatment and carbonization determine gas separation properties.

18.
Environ Toxicol ; 36(9): 1758-1764, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34048126

RESUMEN

Use of paclitaxel as monotherapy or in combination with other therapeutic agents is a widely employed front-line chemotherapeutic strategy for cervical cancer. However, previous reports have shown that approximately 70% of the patients with cervical cancer develop resistance to paclitaxel. Epithelial-mesenchymal transition (EMT) contributes to the occurrence of chemoresistance in several types of cancer, including cervical cancer. Identification of the critical signaling pathway that regulates the EMT process may provide a novel strategy for avoiding or delaying the emergence of paclitaxel resistance during the treatment of cervical cancer. Herein, we established a paclitaxel-resistant cervical cancer cell line (HeLa-229PTR cells) by culturing parental HeLa-229 cells with increasing concentrations of paclitaxel. We observed elevated expression of Notch1 in HeLa-229PTR cells compared with their parental HeLa-229 cells, indicating its potential involvement in the EMT phenotype of the paclitaxel-resistant cells. Furthermore, silencing of the NOTCH1 gene, as well as treatment with a γ-secretase inhibitor (DAPT) partially reversed the EMT phenotype and significantly enhanced the sensitivity of HeLa-229PTR cells to paclitaxel. Moreover, we found that DAPT could significantly inhibit invasiveness, reduce colony formation activity, and promote apoptosis of HeLa-229PTR cells. Taken together, these results indicated that HeLa-229PTR cells develop the EMT phenotype partly through activation of Notch1 signaling. Thus, inhibition of Notch1 signaling can be a strategy for the reversal of the EMT phenotype and may increase the sensitivity of cervical cancer cells to treatment with paclitaxel.


Asunto(s)
Transición Epitelial-Mesenquimal , Neoplasias del Cuello Uterino , Línea Celular Tumoral , Movimiento Celular , Resistencia a Antineoplásicos , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Paclitaxel/farmacología , Transducción de Señal , Neoplasias del Cuello Uterino/genética
19.
BMC Plant Biol ; 21(1): 55, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33478393

RESUMEN

BACKGROUND: Intercropping is often used in the tea producing areas where land resources are not so abundant, and the produced green tea is tasted more delicious through a tea-Chinese chestnut intercropping system according to the experience of indigenous farmers. The length and weight of tea leaf increase under this intercropping system and their root systems are stratified vertically and coordinate symbiosis. However, the delicacy mechanism under the intercropping is not fully understood. RESULTS: Green tea from the Chinese chestnut-tea intercropping system established in the 1980s ranked highest compared with a pure tea plantation from the same region. Based on the non-targeted metabolomics, 100 differential metabolites were upregulated in the tea leaves from intercropping system relative to monoculture system. Twenty-one amino acids were upregulated and three downregulated in response to the intercropping based on the targeted metabolomics; half of the upregulated amino acids had positive effects on the tea taste. Levels of allantoic acid, sugars, sugar alcohols, and oleic acid were higher and less bitter flavonoids in the intercropping system than those in monoculture system. The upregulated metabolites could promote the quality of tea and its health-beneficial health effects. Flavone and flavonol biosynthesis and phenylalanine metabolism showed the greatest difference. Numerous pathways associated with amino acid metabolism altered, suggesting that the intercropping of Chinese chestnut-tea could greatly influence amino acid metabolism in tea plants. CONCLUSIONS: These results enhance our understanding of the metabolic mechanisms by which tea quality is improved in the Chinese chestnut-tea intercropping system and demonstrate that there is great potential to improve tea quality at the metabolomic level by adopting such an intercropping system.


Asunto(s)
Aminoácidos/metabolismo , Camellia sinensis/metabolismo , Producción de Cultivos/métodos , Metaboloma , Té/normas , Camellia sinensis/química , Cromatografía Liquida , Flavonoides/metabolismo , Espectrometría de Masas , Redes y Vías Metabólicas , Metabolómica , Hojas de la Planta/química , Hojas de la Planta/metabolismo
20.
Artículo en Inglés | MEDLINE | ID: mdl-35096099

RESUMEN

A suitable health literacy assessment instrument for patients with chronic pain (HLCP) in China with good instrument's psychometric properties is required. A theoretical framework for the HLCP was developed by adopting the hierarchical model of health literacy proposed by Nutbeam. The reliability and validity of the HLCP were tested in a cross-sectional survey of 237 chronic pain patients from three pain clinics and wards of Grade-3A hospitals in Zhejiang Province, China. The discriminant degree method, correlation analysis method, factor analysis method (exploratory factor analysis), half reliability, and other methods were utilized to screen items for inclusion in the final version of HLCP, and the fitness of the model was subsequently evaluated by confirmatory factor analysis. Cronbach's alpha value and test-retest with two-week intervals were used to test the internal consistency and retest reliability of the HLCP. In the exploratory factor analysis, three domains, functional health literacy (10 items), interactive health literacy (14 items), and critical health literacy (7 items), comprising 31 items in total, were finally loaded; the model was determined to explain 70.9% of the total variance. HLCP's effective assessment of the health literacy level of patients with chronic pain and its acceptable reliability and validity were revealed through the results.

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