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1.
Proc Natl Acad Sci U S A ; 119(25): e2201761119, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35709319

RESUMEN

The BABY BOOM (BBM) AINTEGUMENTA-LIKE (AIL) AP2/ERF domain transcription factor is a major regulator of plant cell totipotency, as it induces asexual embryo formation when ectopically expressed. Surprisingly, only limited information is available on the role of BBM during zygotic embryogenesis. Here we reexamined BBM expression and function in the model plant Arabidopsis thaliana (Arabidopsis) using reporter analysis and newly developed CRISPR mutants. BBM was expressed in the embryo from the zygote stage and also in the maternal (nucellus) and filial (endosperm) seed tissues. Analysis of CRISPR mutant alleles for BBM (bbm-cr) and the redundantly acting AIL gene PLETHORA2 (PLT2) (plt2-cr) uncovered individual roles for these genes in the timing of embryo progression. We also identified redundant roles for BBM and PLT2 in endosperm proliferation and cellularization and the maintenance of zygotic embryo development. Finally, we show that ectopic BBM expression in the egg cell of Arabidopsis and the dicot crops Brassica napus and Solanum lycopersicon is sufficient to bypass the fertilization requirement for embryo development. Together these results highlight roles for BBM and PLT2 in seed development and demonstrate the utility of BBM genes for engineering asexual embryo development in dicot species.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Endospermo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica napus/genética , Brassica napus/crecimiento & desarrollo , Endospermo/genética , Endospermo/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Semillas/genética , Semillas/crecimiento & desarrollo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
2.
Anal Bioanal Chem ; 416(16): 3737-3750, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38503987

RESUMEN

The D-dimer is a sensitive indicator of coagulation and fibrinolysis activation, especially valuable as a biomarker of intravascular thrombosis. Measurement of plasma D-dimer levels plays a crucial role in the diagnosis and monitoring of conditions such as deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation. A variety of immunoassays, including enzyme-linked immunosorbent assays, latex-enhanced immunoturbidimetric assays, whole-blood aggregation analysis, and immunochromatography assays, are widely used in clinical settings to determine D-dimer levels. However, the results obtained from different D-dimer assays vary significantly. These assays exhibit intra-method coefficients of variation ranging from 6.4% to 17.7%, and the measurement discrepancies among different assays can be as high as 20-fold. The accuracy and reliability of D-dimer testing cannot be guaranteed due to the lack of an internationally endorsed reference measurement system (including reference materials and reference measurement procedures), which may lead to misdiagnosis and underdiagnosis, limiting its full clinical application. In this review, we present an in-depth analysis of clinical D-dimer testing, summarizing the existing challenges, the current state of metrology, and progress towards harmonization. We also review the latest advancements in D-dimer detection techniques, which include mass spectrometry and electrochemical and optical immunoassays. By comparing the basic principles, the definition of the measurand, and analytical performance of these methods, we provide an outlook on the potential improvements in D-dimer clinical testing.


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Humanos , Inmunoensayo/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Biomarcadores/sangre
3.
Acta Pharmacol Sin ; 45(6): 1130-1141, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38195693

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most common malignancy, presenting a formidable challenge to the medical community owing to its intricate pathogenic mechanisms. Although current prevention, surveillance, early detection, diagnosis, and treatment have achieved some success in preventing HCC and controlling overall disease mortality, the imperative to explore novel treatment modalities for HCC remains increasingly urgent. Epigenetic modification has emerged as pivotal factors in the etiology of cancer. Among these, RNA N6-methyladenosine (m6A) modification stands out as one of the most prevalent, abundant, and evolutionarily conserved post-transcriptional alterations in eukaryotes. The literature underscores that the dynamic and reversible nature of m6A modifications orchestrates the intricate regulation of gene expression, thereby exerting a profound influence on cell destinies. Increasing evidence has substantiated conspicuous fluctuations in m6A modification levels throughout the progression of HCC. The deliberate modulation of m6A modification levels through molecular biology and pharmacological interventions has been demonstrated to exert a discernible impact on the pathogenesis of HCC. In this review, we elucidate the multifaceted biological functions of m6A modifications in HCC, and concurrently advancing novel therapeutic strategies for the management of this malignancy.


Asunto(s)
Adenosina , Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Animales , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , ARN/metabolismo , ARN/genética
4.
Anal Chem ; 95(27): 10231-10240, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37322584

RESUMEN

Due to the highly heterogeneous nature of hepatocellular carcinoma (HCC), the accurate diagnosis of HCC during the early phase of development is still a challenging task. Therefore, the further development of novel diagnostic methods by discovering new biomarkers is required to improve the rate of HCC diagnosis in the early phase. In this work, an oxygen-modified three-dimensional interconnected porous carbon probe is designed and fabricated to profile the differences of N-glycans in human serum from health controls (H) and patients with hepatic dysfunction (HD) and HCC for the discovery of new biomarkers with HCC development. Excitingly, we discovered that the expression levels of 12 serum N-glycans were gradually increased from H to patients with HD and eventually to patients with HCC. Moreover, two machine learning models established based on these 12 serum N-glycans reached a satisfactory accuracy for predicting HCC development where the receiver operating characteristic curve arrived above 0.95 for distinguishing healthy controls and patients with liver diseases (HD or HCC) and the ROC curve arrived at 0.85 for distinguishing HD and HCC. Our work not only developed a new method for the large-scale characterization of serum N-glycans but also provided valuable guidance for accurate and highly sensitive diagnosis of early liver cancer development in a non-invasive manner.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico , Porosidad , Biomarcadores de Tumor , Biomarcadores , Curva ROC , Polisacáridos
5.
Anal Chem ; 95(20): 8011-8019, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37154434

RESUMEN

Traditional lateral flow assay (LFA) is restricted to providing qualitative or semi-quantitative results and often requires special equipment for obtaining quantitative results. Herein, we proposed a naked-eye readout distance quantitative lateral flow assay based on the permeability changes in enzyme-catalyzed hydrogelation, which not only has the advantages of being simple, immediate, of high efficiency and low cost, and accurate in quantification but also avoids the use of special equipment. The developed LFA method includes three principal components of a nitrocellulose (NC) membrane containing a control line (C line) loading goat anti-rabbit (GAR) antibodies and a test line (T line) loading specific antibodies, alginate-tyramine conjugates forming a hydrogel in the presence of hydrogen peroxide (H2O2) and horseradish peroxidase (HRP), and the HRP-AuNPs-Ab probe only labeling targets captured on the T line. Hemoglobin A1c (HbA1c) was chosen as a representative example to demonstrate the feasibility of our method. Under the optimal conditions, the developed LFA method shows excellent performance in standard samples and real human blood samples where the results of real human blood samples show a high linear correlation with the clinical data obtained by ion exchange chromatography (R2 = 0.9929) and the margin of recovery is only 3.8%. All results demonstrated that our developed LFA method not only has enormous potential in the quantitative detection of HbA1c in clinical complex samples but also can serve as a versatile method for highly efficient detection of other target biomolecules due to the fungibility of antibodies.


Asunto(s)
Peróxido de Hidrógeno , Nanopartículas del Metal , Animales , Humanos , Conejos , Hemoglobina Glucada , Peróxido de Hidrógeno/química , Oro/química , Nanopartículas del Metal/química , Anticuerpos , Permeabilidad , Catálisis
6.
Chemistry ; 29(14): e202203977, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36576084

RESUMEN

The electrochemical reduction of carbon dioxide (CO2 ) to value-added chemicals is a promising strategy to mitigate climate change. Metalloporphyrins have been used as a promising class of stable and tunable catalysts for the electrochemical reduction reaction of CO2 (CO2 RR) but have been primarily restricted to single-carbon reduction products. Here, we utilize functionalized earth-abundant manganese tetraphenylporphyrin-based (Mn-TPP) molecular electrocatalysts that have been immobilized via electrografting onto a glassy carbon electrode (GCE) to convert CO2 with overall 94 % Faradaic efficiencies, with 62 % being converted to acetate. Tuning of Mn-TPP with electron-withdrawing sulfonate groups (Mn-TPPS) introduced mechanistic changes arising from the electrostatic interaction between the sulfonate groups and water molecules, resulting in better surface coverage, which facilitated higher conversion rates than the non-functionalized Mn-TPP. For Mn-TPP only carbon monoxide and formate were detected as CO2 reduction products. Density-functional theory (DFT) calculations confirm that the additional sulfonate groups could alter the C-C coupling pathway from *CO→*COH→*COH-CO to *CO→*CO-CO→*COH-CO, reducing the free energy barrier of C-C coupling in the case of Mn-TPPS. This opens a new approach to designing metalloporphyrin catalysts for two carbon products in CO2 RR.

7.
Int J Mol Sci ; 24(6)2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36982520

RESUMEN

Candida albicans is the main causal pathogen of fungal infections in human beings. Although diverse anti-C. albicans drugs have been explored, the drug resistance and side effects of these drugs are intensifying. Thus, it is urgent to explore new anti-C. albicans compounds from natural products. In this study, we identified trichoderma acid (TA), a compound from Trichoderma spirale with a strong inhibitory effect on C. albicans. Transcriptomic and iTRAQ-based proteomic analyses of TA-treated C. albicans in combination with scanning electronic microscopy and reactive oxygen species (ROS) detection were performed to investigate the potential targets of TA. The most significant differentially expressed genes and proteins after TA treatment were verified through Western blot analysis. Our results revealed that mitochondrial membrane potential, endoplasmic reticulum, ribosomes in the mitochondria, and cell walls were disrupted in TA-treated C. albicans, leading to the accumulation of ROS. The impaired enzymatic activities of superoxide dismutase further contributed to the increase in ROS concentration. The high concentration of ROS led to DNA damage and cell skeleton destruction. The expression levels of Rho-related GTP-binding protein RhoE (RND3), asparagine synthetase (ASNS), glutathione S-transferase, and heat shock protein 70 were significantly up-regulated in response to apoptosis and toxin stimulation. These findings suggest that RND3, ASNS, and supereoxide dismutase 5 are the potential targets of TA, as further demonstrated through Western blot analysis. The combination of transcriptomic, proteomic, and cellular analyses would provide clues for the anti-C. albicans mechanism of TA and the defensive response mechanism of C. albicans. TA is thus recognized as a promising new anti-C. albicans leading compound that alleviates the hazard of C. albicans infection in human beings.


Asunto(s)
Candida albicans , Trichoderma , Humanos , Antifúngicos/farmacología , Antifúngicos/metabolismo , Trichoderma/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteómica , Pruebas de Sensibilidad Microbiana
8.
Anal Chem ; 94(43): 15076-15084, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36265544

RESUMEN

Efficient isolation and downstream bioinformation analysis of circulating tumor cells (CTCs) in whole blood contribute to the early diagnosis of cancer and investigation of cancer metastasis. However, the separation and release of CTCs remain a great challenge due to the extreme rarity of CTCs and severe interference from other cells in complex clinical samples. Herein, we developed a low-cost and easy-to-fabricate aptamer-functionalized wafer with a three-dimensional (3D) interconnected porous structure by grafting polydopamine (PDA), poly(ethylene glycol) (PEG), and aptamer in sequence (Ni@PDA-PEG-Apt) for the capture and release of CTCs. The Ni@PDA-PEG-Apt wafer integrated the features of Ni foam with a 3D interconnected porous structure offering enough tunnels for cells to flow through and enhancing aptamer-cell contact frequency, the spacer PEG with flexible and high hydrophilic property increasing anti-interference ability and providing the wafer with more binding sites for aptamer, which result in an enhanced capture specificity and efficiency for CTCs. Because of these advantages, the Ni@PDA-PEG-Apt wafer achieved a high capture efficiency of 78.25%. The captured cancer cells were mildly released by endonuclease with up to 61.85% efficiency and good proliferation. Furthermore, tumor cells were injected into mice and experienced circulation in vivo. In blood samples after circulation, 65% of target tumor cells can be efficiently captured by the wafer, followed by released and recultured cells with high viability. Further downstream metabolomics analysis showed that target cancer cells remained with high biological activity and can be well separated from MCF-10A cells based on metabolic profiles by the PCA analysis, indicating the great potential of our strategy for further research on the progression of cancer metastasis. Notably, not only is the wafer cheap with a cost of only 3.58 U.S. dollars and easily prepared by environmental-friendly reagents but also the process of capturing and releasing tumor cells can be completed within an hour, which is beneficial for large-scale clinical use in the future.


Asunto(s)
Células Neoplásicas Circulantes , Ratones , Animales , Células Neoplásicas Circulantes/patología , Porosidad , Recuento de Células , Polietilenglicoles/química , Separación Celular/métodos , Línea Celular Tumoral
9.
Int J Clin Oncol ; 27(1): 154-164, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34800178

RESUMEN

BACKGROUND: In the phase III open-label KEYNOTE-426 (NCT02853331) study, first-line pembrolizumab and axitinib improved overall survival (OS) and progression-free survival (PFS) versus sunitinib for metastatic renal cell carcinoma (mRCC). KEYNOTE-426 evaluated patients enrolled from 25 sites in Japan. METHODS: Patients enrolled in Japan were included in this post hoc subgroup analysis. Adults with clear cell mRCC were randomly assigned 1:1 to receive intravenous pembrolizumab 200 mg every 3 weeks plus oral axitinib 5 mg twice daily or oral sunitinib 50 mg once daily (4 weeks on/2 weeks off). Dual primary endpoints were OS and PFS as assessed by blinded independent central review. Objective response rate (ORR) and safety were secondary endpoints. RESULTS: The Japanese subgroup comprised 94 patients (pembrolizumab-axitinib, n = 44; sunitinib, n = 50; 11% of the intent-to-treat population). Median time from randomization to data cutoff (January 6, 2020) was 29.5 months (range 24.6-37.3). Consistent with the intent-to-treat population, the OS, PFS, and ORR suggested improvement with pembrolizumab-axitinib versus sunitinib in the Japanese subgroup. Grade ≥ 3 treatment-related adverse events (TRAEs) occurred in 70% of patients receiving pembrolizumab-axitinib versus 78% receiving sunitinib; 11 (25%) patients receiving pembrolizumab-axitinib and 13 (27%) patients receiving sunitinib discontinued the study medication due to AEs. TRAEs led to the discontinuation of pembrolizumab, axitinib, pembrolizumab-axitinib, or sunitinib in 32%, 34%, 14%, and 20%, respectively. No deaths from TRAEs occurred. CONCLUSIONS: Efficacy outcomes for the Japanese subgroup were consistent with those of the global population. Safety in Japanese patients was consistent with the results from the global population.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Axitinib , Carcinoma de Células Renales , Neoplasias Renales , Sunitinib , Protocolos de Quimioterapia Combinada Antineoplásica , Axitinib/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Humanos , Japón , Neoplasias Renales/tratamiento farmacológico , Sunitinib/uso terapéutico
10.
J Integr Plant Biol ; 64(6): 1281-1294, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35249255

RESUMEN

Doubled haploid (DH) technology is used to obtain homozygous lines in a single generation, a technique that significantly accelerates the crop breeding trajectory. Traditionally, in vitro culture is used to generate DHs, but this technique is limited by species and genotype recalcitrance. In vivo haploid induction (HI) through seed is widely and efficiently used in maize and was recently extended to several other crops. Here we show that in vivo HI can be triggered by mutation of DMP maternal haploid inducer genes in allopolyploid (allotetraploid) Brassica napus and Nicotiana tabacum. We developed a pipeline for selection of DMP orthologs for clustered regularly interspaced palindromic repeats mutagenesis and demonstrated average amphihaploid induction rates of 2.4% and 1.2% in multiple B. napus and N. tabacum genotypes, respectively. These results further confirmed the HI ability of DMP gene in polyploid dicot crops. The DMP-HI system offers a novel DH technology to facilitate breeding in these crops. The success of this approach and the conservation of DMP genes in dicots suggest the broad applicability of this technique in other dicot crops.


Asunto(s)
Brassica napus , Brassica napus/genética , Productos Agrícolas/genética , Haploidia , Fitomejoramiento , Poliploidía , Nicotiana/genética
11.
Angew Chem Int Ed Engl ; 61(4): e202112880, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-34694675

RESUMEN

The melting behaviour of metal-organic frameworks (MOFs) has aroused significant research interest in the areas of materials science, condensed matter physics and chemical engineering. This work first introduces a novel method to fabricate a bimetallic MOF glass, through melt-quenching of the cobalt-based zeolitic imidazolate framework (ZIF) [ZIF-62(Co)] with an adsorbed ferric coordination complex. The high-temperature chemically reactive ZIF-62(Co) liquid facilitates the formation of coordinative bonds between Fe and imidazolate ligands, incorporating Fe nodes into the framework after quenching. The resultant Co-Fe bimetallic MOF glass therefore shows a significantly enhanced oxygen evolution reaction performance. The novel bimetallic MOF glass, when combined with the facile and scalable mechanochemical synthesis technique for both discrete powders and surface coatings on flexible substrates, enables significant opportunities for catalytic device assembly.

12.
J Am Chem Soc ; 143(25): 9507-9514, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34143615

RESUMEN

Strontium cobaltite-based perovskites (SrCoO3-δ) have been widely studied as a promising cathode for the next-generation solid-oxide fuel cell (SOFC). Here, we found a balance between oxygen vacancy (VO) formation and its migration in designing SrCoO3-δ-based materials by using two activity descriptors, i.e., radius and electronegativity. The ORR activity of these types of perovskites is found to strongly rely on the two proposed descriptors, and Nb- or Ta-doped SrCoO3-δ locates in the promising zone as predicted with a moderate value of both VO formation energy and ion migration barrier. Then Sc-Ta co-doped SrCoO3-δ (SSTC) and Sc-Nb co-doped SrCoO3-δ (SSNC) are screened out to be the best among 91 bimetal-doped SrCoO3-δ perovskites. Further experiments have been carried out to synthesize the co-doped SSTC and prove ultralow area-specific resistance values (0.071, 0.198, and 0.701 Ω·cm2 at 550, 500, and 450 °C, respectively), which is only one-third of that of benchmark materials for the SOFC cathodes. Our results open a novel pathway in designing SOFC cathodes with an optimal performance.

13.
Small ; 17(29): e2101573, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34137160

RESUMEN

Single-phase perovskite oxides that contain nonprecious metals have long been pursued as candidates for catalyzing the oxygen evolution reaction, but their catalytic activity cannot meet the requirements for practical electrochemical energy conversion technologies. Here a cation deficiency-promoted phase separation strategy to design perovskite-based composites with significantly enhanced water oxidation kinetics compared to single-phase counterparts is reported. These composites, self-assembled from perovskite precursors, comprise strongly interacting perovskite and related phases, whose structure, composition, and concentration can be accurately controlled by tailoring the stoichiometry of the precursors. The composite catalyst with optimized phase composition and concentration outperforms known perovskite oxide systems and state-of-the-art catalysts by 1-3 orders of magnitude. It is further demonstrated that the strong interfacial interaction of the composite catalysts plays a key role in promoting oxygen ionic transport to boost the lattice-oxygen participated water oxidation. These results suggest a simple and viable approach to developing high-performance, perovskite-based composite catalysts for electrochemical energy conversion.

14.
Macromol Rapid Commun ; 42(21): e2100441, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34431573

RESUMEN

Using DNA nanostructures as templates to synthesize shape-controlled polydopamine (PDA) is a promising strategy to realize the fabrication of exquisite PDA nanomaterials. However, previous studies using small DNA tiles as templates could only afford very simple structures such as lines and crosses due to the limited space on the template and the relatively low resolution of the PDA nanopatterns. Therefore, the best resolution of the PDA nanostructures that can be achieved by this technique is carefully investigated. And by connecting several DNA tiles together, larger DNA templates are built up and achieve the synthesis of complicated digital nanopatterned PDA structures.


Asunto(s)
Nanoestructuras , Polímeros , ADN , Indoles
15.
Environ Res ; 198: 110458, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33188763

RESUMEN

Wastewater treatment plants (WWTPs) play a critical role in the sustainable development of water resources due to its outstanding ability of removing pollutants from complex influent wastewater and generating clean and safe effluent. This paper innovatively adopted the meta-analysis method in view of published LCA studies to assess the energy use and environmental impacts of WWTPs during their life cycle. The search and screening process determined a useful data source with 54 LCA literatures covering 109 relevant case studies. The meta-analysis results revealed that, compared with other regions, the WWTPs in China have the higher intensity in terms of energy use, global warming potential (GWP), eutrophication potential (EP), acidification potential (AP), photochemical oxidation (PHO), freshwater ecotoxicity potential (FETP) and terrestrial ecotoxicity potential (TETP) categories, implying that the energy conservation and emission reduction strategies are necessary to wastewater treatment industry in China. Moreover, compared with A/A/O and CASS processes, the A/O process consumes less energy and results in lower GWP and AP intensity, but affects adversely the natural water-body protection due to undesirable treatment efficiency. Furthermore, the treatment capacities of medium and large scales (i.e. 5-20 × 104 m3/d) are most reasonable sizes for WWTPs since their intensity of energy use, GWP, EP and AP are under a relatively low level. Finally, a strict effluent discharge standard is highly recommended from the perspective of protecting aquatic environment, although it leads to a higher energy consumption. The findings of this study could provide valuable references for promoting healthy and sustainable wastewater treatment industry.


Asunto(s)
Purificación del Agua , Animales , China , Ambiente , Estadios del Ciclo de Vida , Eliminación de Residuos Líquidos , Aguas Residuales
16.
J Environ Manage ; 299: 113605, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34454203

RESUMEN

Multifunctional cultivated land has both sides of supply and demand, and their matches are very important to boost the high-quality development of agriculture and rural areas. The supply-demand match index and GIS spatial analysis were employed to explore the supply-demand mismatches and synergic strategies of multifunctional cultivated land. Taking the Wuhan Metropolitan Area (WMA), China as an example, we obtained the following results: (1) There were obvious supply-demand mismatches of multifunctional cultivated land in the production function, ecological function, and landscape culture function. The spatial distribution of supply-demand mismatches of the three different functions of cultivated land is different. The supply of cultivated land production function is less than the demand, while the supply of landscape culture function is greater than the demand. The supply matches the demand of cultivated land in the ecological function. (2) The supply-demand mismatches of multifunctional cultivated land have scale effects. From the 1 km × 1 km grid scale to the township, county (district), and prefecture-level city scales, the proportion of deficit regions of production function and ecological function decreases with increasing scale. In contrast, the deficit regions of landscape culture function are always concentrated in the center of the WMA. It is considered that we should improve the supply of cultivated land in the production function, protect ecological function and enhance the demand of landscape culture function. Moreover, the management of multifunctional cultivated land needs to strengthen the multiscale spatial linkage and differential strategies of the supply side and demand side.


Asunto(s)
Agricultura , Conservación de los Recursos Naturales , China , Ciudades , Análisis Espacial
17.
Angew Chem Int Ed Engl ; 59(34): 14664-14670, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32495475

RESUMEN

The oxygen vacancies of defective iron-cobalt oxide (FeCoOx -Vo) nanosheets are modified by the homogeneously distributed sulfur (S) atoms. S atoms can not only effectively stabilize oxygen vacancies (Vo), but also form the Co-S coordination with Co active site in the Vo, which can modulate the electronic structure of the active site, enabling FeCoOx -Vo-S to exhibit much superior OER activity. FeCoOx -Vo-S exhibits a mass activity of 2440.0 A g-1 at 1.5 V vs. RHE in 1.0 m KOH, 25.4 times higher than that of RuO2 . The Tafel slope is as low as 21.0 mV dec-1 , indicative of its excellent charge transfer rate. When FeCoOx -Vo-S (anode catalyst) is paired with the defective CoP3 /Ni2 P (cathode catalyst) for overall water splitting, current densities of as high as 249.0 mA cm-2 and 406.0 mA cm-2 at a cell voltage of 2.0 V and 2.3 V, respectively, can be achieved.

18.
Angew Chem Int Ed Engl ; 58(38): 13565-13572, 2019 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-31328904

RESUMEN

Metal-organic framework (MOFs) two-dimensional (2D) nanosheets have many coordinatively unsaturated metal sites that act as active centres for catalysis. To date, limited numbers of 2D MOFs nanosheets can be obtained through top-down or bottom-up synthesis strategies. Herein, we report a 2D oxide sacrifice approach (2dOSA) to facilely synthesize ultrathin MOF-74 and BTC MOF nanosheets with a flexible combination of metal sites, which cannot be obtained through the delamination of their bulk counterparts (top-down) or the conventional solvothermal method (bottom-up). The ultrathin iron-cobalt MOF-74 nanosheets prepared are only 2.6 nm thick. The sample enriched with surface coordinatively unsaturated metal sites, exhibits a significantly higher oxygen evolution reaction reactivity than bulk FeCo MOF-74 particles and the state-of-the-art MOF catalyst. It is believed that this 2dOSA could provide a new and simple way to synthesize various ultrathin MOF nanosheets for wide applications.

20.
Mol Pain ; 11: 70, 2015 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-26576537

RESUMEN

BACKGROUND: Altered kallikrein-related peptidase activity and bradykinin are associated with skin disorders in humans and mice under chronic inflammation conditions. The bradykinin B1 receptor (B1R), also known as one of the G-protein-coupled receptor family and usually absent in intact tissues and upregulated during tissue injury, is responsible for vasodilation, capillary permeability, nociceptor sensitization, and pain; it is indispensable for physiopathological progress in chronic inflammation conditions, but its roles and effectors in the itching sensation of the allergic contact dermatitis model are poorly defined. RESULTS: We focused on incurable itching in a diphenylcyclopropenone (DCP) chronic inflammation experimental model. Preventive treatment with the B1R antagonist R892 significantly suppressed spontaneous scratching, while the B2R selective antagonist did not. B1R expression in the skin tissues of this model was detected using a quantitative, real-time polymerase chain reaction, Western blotting, and immunohistochemistry; B1R mRNA and protein levels were increased compared with a sham-treated control group. A higher B1R IHC staining signal was observed in the keratinocytes in DCP-treated mice compared with a vehicle-treated group, so we studied the B1R function when superimposed on a protease-activated receptor 2 (PAR2) background, establishing B1R as a pivotal mediator of PAR2 function in HaCaT cell lines. CONCLUSION: Our data provide evidence that B1R facilitates the chronic itching sensation related to keratinocytes in a DCP-treated chronic inflammation experimental model.


Asunto(s)
Dermatitis Alérgica por Contacto/fisiopatología , Prurito/fisiopatología , Receptor de Bradiquinina B1/metabolismo , Sensación/efectos de los fármacos , Animales , Antipruriginosos/farmacología , Conducta Animal/efectos de los fármacos , Bradiquinina/análogos & derivados , Bradiquinina/farmacología , Línea Celular , Ciclopropanos/farmacología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Queratinocitos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Prurito/inducido químicamente , Receptor de Bradiquinina B1/genética
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