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1.
J Environ Manage ; 356: 120664, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508006

RESUMO

Continuous discharge of wastewater, emissions, and solid wastes from steelworks poses environmental risks to ecosystems. However, the role of keystone taxa in maintaining multifunctional stability during environmental disturbances remains poorly understood. To address this, we investigated the community diversity, assembly mechanisms, and soil multifunctionality of soils collected from within the steelworks (I), within 2.5 km radius from the steelworks (E), and from an undisturbed area (CK) in Jiangsu Province, China, via 16 S rRNA sequencing. Significant differences were found in the Chao1 and the richness indexes of the total taxa (p < 0.05), while the diversity of keystone taxa was not significant at each site (p > 0.05). The deterministic processes for total taxa were 42.9%, 61.9% and 47.7% in CK, E, and I, respectively. Steelworks stress increased the deterministicity of keystone taxa from 52.3% in CK to 61.9% in E and I soils. The average multifunctionality indices were 0.518, 0.506 and 0.513 for CK, E and I, respectively. Although the soil multifunctionality was positive correlated with α diversity of both the total and keystone taxa, the average degree of keystone taxa in functional network increased significantly (79.96 and 65.58, respectively), while the average degree of total taxa decreased (44.59 and 51.25, respectively) in the E and I. This suggests keystone taxa contribute to promoting the stability of ecosystems. With increasing disturbance, keystone taxa shift their function from basic metabolism (ribosome biogenesis) to detoxification (xenobiotics biodegradation, metabolism, and benzoate degradation). Here we show that keystone taxa are the most important factor in maintaining stable microbial communities and functions, providing new insights for mitigating pollution stress and soil health protection.


Assuntos
Microbiota , Solo , Microbiologia do Solo , Bactérias/genética , Poluição Ambiental
2.
Int Immunopharmacol ; 130: 111708, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38394889

RESUMO

Immunoevasion has been a severe obstacle for the clinical treatment of breast cancer (BC). CD47, known as an anti-phagocytic molecule, plays a key role in governing the evasion of tumor cells from immune surveillance by interacting with signal-regulated protein α (SIRPα) on macrophages. Here, we report for the first time that miR-299-3p is a direct regulator of CD47 with tumor suppressive effects both in vitro and in vivo. miRNA expression profiles and overall survival of BC cohorts from the Cancer Genome Atlas, METABRIC, or GSE19783 datasets showed that miR-299-3p is downregulated in BC tissues and that BC patients with low levels of miR-299-3p have poorer prognoses. Using dual-luciferase reporter, qRT-PCR, Western blot, and phagocytosis assays, we proved that restoration of miR-299-3p can suppress CD47 expression by directly targeting the predicted seed sequence "CCCACAU" in its 3'-UTR, leading to phagocytosis of BC cells by macrophages, whereas miR-299-3p inhibition or deletion reversed this effect. Additionally, Gene Ontology (GO) analysis and a variety of confirmatory experiments revealed that miR-299-3p was inversely correlated with cell proliferation, migration, and the cell cycle process. Mechanistically, miR-299-3p can also directly target ABCE1, an essential ribosome recycling factor, alleviating these malignant phenotypes of BC cells. In vivo BC xenografts based on nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice further proved that restoration of miR-299-3p resulted in a significant suppression of tumorigenesis and a promotion of macrophage activation and infiltration. Overall, our study suggested that miR-299-3p is a potent inhibitor of CD47 and ABCE1 to exhibit bifunctional BC-suppressing effects through immune activation conjugated with malignant behavior inhibition in breast carcinogenesis and thus can potentially serve as a novel therapeutic target for BC.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Neoplasias da Mama , Antígeno CD47 , MicroRNAs , Evasão Tumoral , Animais , Feminino , Humanos , Camundongos , Transportadores de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinogênese , Antígeno CD47/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Macrófagos/metabolismo , Camundongos Endogâmicos NOD , Camundongos SCID , MicroRNAs/metabolismo , Fagocitose/genética , Fenótipo
3.
Adv Mater ; 36(4): e2308193, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37847882

RESUMO

Rechargeable batteries are widely used as power sources for portable electronics, electric vehicles and smart grids. Their practical performances are, however, largely undermined under extreme conditions, such as in high-altitude drones, ocean exploration and polar expedition. These extreme environmental conditions not only bring new challenges for batteries but also incur unique battery failure mechanisms. To fill in the gap, it is of great importance to understand the battery failure mechanisms under different extreme conditions and figure out the key parameters that limit battery performances. In this review, the authors start by investigating the key challenges from the viewpoints of ionic/charge transfer, material/interface evolution and electrolyte degradation under different extreme conditions. This is followed by different engineering approaches through electrode materials design, electrolyte modification and battery component optimization to enhance practical battery performances. Finally, a short perspective is provided about the future development of rechargeable batteries under extreme conditions.

4.
Adv Mater ; 35(52): e2307736, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37909806

RESUMO

There has been increasing interests in π-d conjugated coordination polymers (CCPs) for energy storage because of their rapid charge transfer through long-range planar π-d conjugation between ligands and metal centers. Nevertheless, currently reported CCPs for energy storage are mostly based on 1D or 2D structures. There are few 3D CCPs reported to date because of the great challenge in constructing nonplanar coordination geometries, let alone their applications in multivalent ions storage. Herein, a triphenylene-catecholate-based 3D CCP (Mn-HHTP) is successfully synthesized assembled from the multidentate chelating groups of hexahydroxytriphenylene (HHTP) ligands and their isotropic coordination with Mn2+ ions. The 3D conjugated structure of Mn-HHTP enables an exceptional cycle life of >4000 cycles at 0.5 A g-1 for multivalent Mg2+ ion storage, which is far superior to most organic and inorganic electrode materials. Experimental characterizations combined with theoretical calculations indicate that the semiquinone radicals at the HHTP ligands are the electroactive centers for Mg2+ ions storage. The excellent performance of Mn-HHTP opens a new avenue towards the design of 3D CCPs for long-life rechargeable magnesium-ion batteries.

5.
Environ Int ; 179: 108175, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37683504

RESUMO

Organic fertilizer microbiomes play substantial roles in soil ecological functions, including improving soil structure, crop yield, and pollutant dissipation. However, limited information is available about the ecological functions of phages and phage-encoded auxiliary metabolic genes (AMGs) in orga9nic fertilizers. Here we used a combination of metagenomics and phage transplantation trials to investigate the phage profiles and their potential roles in pesticide degradation in four organic fertilizers from different sources. Phage annotation results indicate that the two vermicomposts made from swine (PV) and cattle (CV) dung had more similar phage community structures than the swine (P) and cattle (C) manures. After vermicomposting, the organic fertilizers (PV and CV) exhibited enriched phage-host pairings and phage AMG diversity in relative to the two organic fertilizers (P and C) without composting. In addition, the number of broad-host-range phages in the vermicomposts (182) was higher than that in swine (153) and cattle (103) manures. Notably, phage AMGs associated with metabolism and pesticide biodegradation were detected across the four organic fertilizers. The phage transplantation demonstrated that vermicompost phages were most effective at facilitating the degradation of pesticide precursor p-nitrochlorobenzene (p-NCB) in soil, as compared to swine and cattle manures (P < 0.05). Taken together, our findings highlight the significance of phages in vermicompost for biogeochemical cycling and biodegradation of pesticide-associated chemicals in contaminated soils.


Assuntos
Bacteriófagos , Praguicidas , Animais , Bovinos , Suínos , Praguicidas/toxicidade , Fertilizantes , Bacteriófagos/genética , Biodegradação Ambiental , Esterco , Solo
6.
Healthcare (Basel) ; 11(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37510491

RESUMO

This study examines the impact of living arrangements and social capital on the subjective well-being of the elderly, as well as the mutual effects and relationships between the well-being and self-rated health status of the elderly. A total of 369 questionnaires were administered, and the effective recovery rate was 98.10%. The results indicate three key findings: (1) the current location for aging in place, social support, social activities, house ownership, and self-rated health status are indispensable factors affecting the well-being of the elderly. The best location for aging in place was the community, where the elderly's sense of well-being was highest-the next best options were aging at home and institutional care. (2) Elderly people with sole ownership of their homes were more likely to have higher levels of well-being than those owning jointly or who were tenants. (3) There was significant interaction between subjective well-being and self-rated health status.

7.
Natl Sci Rev ; 10(1): nwac171, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684521

RESUMO

Two-dimensional covalent organic frameworks are promising for photocatalysis by virtue of their structural and functional diversity, but generally suffer from low activities relative to their inorganic competitors. To fulfill their full potential requires a rational tailoring of their structures at different scales as well as their surface properties. Herein, we demonstrate benzobisthiazole-based covalent organic frameworks as a superior photocatalyst for hydrogen production. The product features high crystallinity with ordered 2.5-nm-wide cylindrical mesopores and great water wettability. These structural advantages afford our polymeric photocatalyst with fast charge carrier dynamics as evidenced by a range of spectroscopic characterizations and excellent catalytic performances when suspended in solution or supported on melamine foams. Under visible-light irradiation, it enables efficient and stable hydrogen evolution with a production rate of 487 µmol h-1 (or a mass-specific rate of 48.7 mmol g-1 h-1)-far superior to the previous state of the art. We also demonstrate that hydrogen production can be stoichiometrically coupled with the oxidation conversion of biomass as exemplified by the conversion of furfuryl alcohol to 2-furaldehyde.

8.
Angew Chem Int Ed Engl ; 62(8): e202215408, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36515631

RESUMO

Aluminum-ion batteries (AIBs) have attracted great attentions in recent years. Organic materials such as polythiophene (PT) are promising cathode for AIBs. However, the capacity and cyclic stability of conventional organic cathode such as PT are limited by the inadequate degree of reaction and the unstable nature of organic materials. To obtain high-performance organic cathode, a new PT with the ability of self-adaptive re-organization was prepared. During cycling, its molecular chain can be re-organized, and the polymerization mode will change from Cα -Cα (α-PT) to Cß -Cß (ß-PT). This change leads to smaller steric hindrance and faster kinetics during ion insertion which can lower the reaction energy barrier and stabilize the molecular structure. Benefited by this, AIBs with this cathode can deliver a specific capacity of 180 mAh g-1 (@2 A g-1 ) and a superb stability of 100 000 cycles at 10 A g-1 . High energy density and power density can also be achieved with this cathode.

9.
J Environ Manage ; 310: 114776, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35219207

RESUMO

Earthworms are important in soil bioremediation because of their capability of pollutant degradation. However, the trade-off between pollutant dissemination and degradation arising from earthworm activities remains unclear, as well as the potential biodegradation mechanism. Herein, an earthworm avoidance experiment was established to investigate Metaphire guillelmi-mediated tetracycline (TC) diffusion and degradation. The results showed that above 1600 mg kg-1 TC pollution in soil induced avoidance behaviour of earthworms (p < 0.05), below which the random worm behaviour accelerated TC diffusion by 8.2% at most (p < 0.05), resulting in elevated levels of antibiotic-resistant bacteria and genes in the soil. Nevertheless, earthworms enhanced TC degradation regardless of whether their avoidance behaviour occurred (14.6-25.8%, p < 0.05). Compared with in soil, metabolic pathways affiliated with xenobiotic degradation and metabolism in the intestines were enriched (LDA >3). Given the abundant glutathione S-transferases in the intestines and their close relationship with Δ degradation, they may play a key role in intestinal TC biodegradation. In general, earthworms had good tolerance to soil TC contamination and their impact on promoting TC degradation outweighed that accelerating TC diffusion. This work provides a comprehensive view of earthworms as a potential remediation method for TC-contaminated soil.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Antibacterianos/metabolismo , Oligoquetos/metabolismo , Solo , Poluentes do Solo/análise , Tetraciclina/metabolismo , Tetraciclina/farmacologia
10.
mSystems ; 7(1): e0125321, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35089099

RESUMO

Exploring the ecological mechanism of microbial community assembly in soil and the earthworm gut in a vanadium polluted environment could help us understand the effects of vanadium stress on microbial diversity maintenance and function, as well as the mechanism of microbial mitigation of vanadium stress. Combining metagenomic sequencing and abundance distribution models, we explored the assembly of earthworm intestinal bacteria and native soil bacteria after 21 days of earthworm exposure to a gradient level of vanadate (0 to 300 mg kg-1) in soil. Stochastic processes dominated the assembly of both genes and taxa in earthworm gut and soil. Both the composition of taxa and functional genes in earthworm gut varied highly with the vanadium concentration, while in soil, only the taxa changed significantly, whereas the functional genes were relatively stable. The functional redundancy in soil, but not in the earthworm gut, was confirmed by a Mantel test and analysis of similarities (ANOSIM) test. In addition, vanadium detoxifying gene (VDG)-carrying taxa were more diverse but less abundant in soil than in the worm gut; and VDGs were more abundant in soil than in the worm gut. Their wider niche breadth indicated that VDG-carrying taxa were generalists in soil, in contrast to their role in the worm gut. These results suggested that earthworm intestinal and soil microbes adopted different strategies to counteract vanadium stress. The results provide new insights into the effects of soil vanadium stress on the assembly of earthworm gut and soil microbiota from both bacterial taxa and genetic function perspectives. IMPORTANCE Metagenomic sequencing revealed the variation of functional genes in the microbial community in soil and earthworm gut with increasing vanadium concentrations, which provided a new insight to explore the effect of vanadium stress on microbial community assembly from the perspective of functional genes. Our results reinforced the view that functional genes and taxa do not appear to have a simple corresponding relationship. Taxa are more sensitive compared with functional genes, suggesting the existence of bacterial functional redundancy in soil, but not in the earthworm gut. These observations indicate different assembly patterns of earthworm intestinal and soil bacteria under vanadium stress. Thus, it is important and necessary to include genetic functions to comprehensively understand microbial community assembly.


Assuntos
Microbioma Gastrointestinal , Microbiota , Oligoquetos , Animais , Solo , Vanádio , Oligoquetos/microbiologia , Bactérias
11.
J Hazard Mater ; 429: 128286, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35086042

RESUMO

Using earthworms to remove soil organic pollutants is a common bioremediation method. However, it remains challenging to evaluate and predict their effect on removing soil organic pollutants based on earthworm toxicology and pollutant degradation rates. Peer-reviewed journal articles on ecotoxicology and bioremediation from the years 1974-2020 (cutoff date September 2020) were selected for meta-analysis to quantify the effect size of earthworms on organic pollutant degradation. The meta-analysis shows that the average effect size of earthworms on organic pollutant degradation is 128.5% (p < 0.05). Soils with high soil organic matter or clay textures are more conducive to earthworm-mediated removal of organic pollutants. Structural equation modeling reveals that earthworms' sensitivity to contaminant exposure may be a greater limiting factor on pollutant degradation than environmental factors. In addition, the quantitative relationship existed between LC50 and the pollutants' degradation that an elevated LC50 threshold resulted in at least 1.5 times increase in the pollutants' degradation size. This correlation was dually confirmed via meta-analysis and the validation trial. The results of this study contribute to a more profound understanding of the potential to use earthworms to mitigate organic pollution in soils and develop earthworm-based soil remediation techniques on a global scale.


Assuntos
Poluentes Ambientais , Oligoquetos , Poluentes do Solo , Animais , Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Oligoquetos/metabolismo , Solo/química , Poluentes do Solo/metabolismo
12.
ACS Appl Mater Interfaces ; 14(1): 826-833, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34939785

RESUMO

Organic electrode materials hold unique advantages for electrochemical alkali-ion storage but cannot yet fulfill their potential. The key lies in the design of structurally stable candidates that have negligible solution solubility and can withstand thousands of cycles under operation. To this end, we demonstrate here the preparation of dimensionally stable polyimide frameworks from the two-dimensional cross-linking of tetraaminobenzene and dianhydride. The product consists of hierarchically assembled nanosheets with thin thickness and abundant porosity. Its robust molecular frameworks and advantageous nanoscale features render our polymeric material a promising cathode candidate for both sodium-ion and potassium-ion batteries. Most strikingly, an extraordinary cycle life of up to 6000 cycles at 2 A g-1 is demonstrated, outperforming most of its competitors. Theoretical simulations support the great activity of our polymeric product for the electrochemical alkali-ion storage.

13.
Adv Mater ; 33(51): e2106079, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34632649

RESUMO

There has been growing research interest in hydrogen bonded organic frameworks (HOFs) by virtue of their great structural crystallinity, large surface areas and porosity. Their potential in electrochemical applications, unfortunately, remains elusive because weak hydrogen bonds would dissociate in solution that eventually compromises the structural integrity. Herein, it is demonstrated that this issue may be overcome by designing and introducing multisite hydrogen bonding within HOFs. 2D molecular sheets are prepared using diaminotriazole as the linkers for the first time. In spite of the molecular thickness (≈1 nm), they are chemically stable and mechanically robust, and have diminished solubility in most polar or nonpolar organic solvents. This solution-stable HOF exhibits an excellent electrochemical performance for Na+ ion storage. In particular, it enables an exceptional cycle life of >10 000 cycles at 1 A g-1 , which is far superior to most other organic electrode materials. Theoretical simulations indicate that the activation barrier for the intralayer or interlayer diffusion of Na+ ions within the organic frameworks is small.

14.
Adv Sci (Weinh) ; 7(16): 2001002, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32832356

RESUMO

There are growing interests in metal-free heteroatom-doped carbons for electrochemical CO2 reduction. Previous studies extensively focus on the effect of N-doping, and their products severely suffer from low current density (mostly <2 mA cm-2) and limited selectivity (<90%). Here, it is reported that heteroatom codoping offers a promising solution to the above challenge. As a proof of concept, N,P-codoped mesoporous carbon is prepared by annealing phytic-acid-functionalized ZIF-8 in NH3. In CO2-saturated 0.5 m NaHCO3, the catalyst enables CO2 reduction to CO with great selectivity close to 100% and large CO partial current density (≈8 mA cm-2), which are, to the best of knowledge, superior to all other relevant competitors. Theoretical simulations show that the improved activity and selectivity are stemmed from the enhanced surface adsorption of *COOH and *CO intermediates as a result of the synergy of N and P codoping.

15.
Nanoscale Horiz ; 5(3): 501-506, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32118217

RESUMO

Introduction of appropriate cathode electrocatalysts in lithium-sulfur or lithium-polysulfide batteries can accelerate the polysulfide interconversion and suppress the shuttle effect. However, improvements are often limited especially under high sulfur loading. Herein, we prepare molybdenum carbide nanostructures and investigate their potential as the cathode electrocatalyst for lithium-polysulfide batteries. The product is prepared by the self-polymerization of dopamine in the presence of Mo7O246- ions, followed by high-temperature carburization. It features ultrasmall α-MoC1-x nanoparticles uniformly dispersed on a hierarchical carbonaceous support. Polysulfide adsorption experiments and electrochemical measurements show that this material has a strong surface affinity toward polysulfides, and can greatly enhance their conversion rate, in particular the Li2S4↔ Li2S2/Li2S conversion. When assessed as the cathode electrocatalyst, it enables lithium-polysulfide batteries with large specific capacity (up to 1400 mA h g-1), impressive rate capability (800 mA h g-1 at 3200 mA g-1) and excellent cycling stability even at high sulfur loading.

16.
ACS Appl Mater Interfaces ; 11(23): 21010-21017, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31149794

RESUMO

Microporous metal-organic frameworks (MOFs) are promising candidate materials for chemical sensing, but the reproducible fabrication of MOF-based sensors with optimized and stable performances remains a significant challenge. Here, we report the fabrication of MOF optical sensors with steady but tunable optical properties via assembling UiO-66 crystals with controllable sizes and missing-linker defects. The well-defined but tunable microscopic and mesoscopic structural features of MOF sensing components greatly facilitate the optimization of device performance. The UiO-66 crystal-assembled sensors display fast response (2.00 s) and short recovery (3.00 s) to ethanol vapor (one of the analytes we tested). Our systematical investigation indicates that the mesoporous features of sensing components contribute greatly to the enhanced sensitivity (by ∼24.6% to the saturated ethanol vapor), response speed (by ∼42.9%), and recovery speed (by ∼59.7%) of the crystal-assembled sensors in comparison to their dense counterpart. The building crystal sizes show a slight influence on the response speed but profound effects on the sensitivity and recovery performances of sensors. The missing-linker defects have obvious beneficial effects on the desorption kinetics of analyte and can cause a faster recovery of sensors.

17.
Sci Bull (Beijing) ; 64(24): 1875-1880, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36659582

RESUMO

Lithium-sulfur batteries are promising candidates for next-generation energy storage but are confronted with several challenges. One of the possible solutions is to design proper cathode electrocatalysts to accelerate the redox interconversion of solvated polysulfide intermediates. Herein, we report cobalt atoms dispersed on hierarchical carbon nitride support as an effective cathode electrocatalyst for lithium-polysulfide batteries. The electrocatalyst material is prepared from the simple reaction between melamine and cyanuric acid in the presence of Co2+, followed by the Ar annealing. The product has a unique hierarchical structure consisting of many thin and porous C3N4 nanosheets finely dispersed with Co atoms. The atomic dispersion of Co species is confirmed by X-ray absorption experiments. Electrochemical measurements reveal that it can promote the interconversion of polysulfides. As a result, batteries using this cathode electrocatalyst achieve large capacity (∼1400 mAh/g at 1.6 mA/cm2), good rate performance (∼800 mAh/g at 12.8 mA/cm2) and impressive cycling stability under different current densities and different sulfur loadings.

18.
ACS Omega ; 3(2): 2437-2443, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31458538

RESUMO

The present study reports a facile and low-cost route to produce a superhydrophobic polymerized n-octadecylsilane surface with micronano hierarchical structure on the surface of quartz crystal microbalance (QCM). The surface is used as a novel functional sensing material to detect benzene, toluene, ethylbenzene, and xylene (BTEX) vapor on the basis of QCM platform. The composites were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and contact angle measurements. The type of solvent used to dissolve N-octadecyltrichlorosilane has a big impact on the morphology, wettability, and sensing performance of the polymer material. Further systematic studies suggest that surface wettability (contact angle) and molecular polarity of the detected analytes are effective factors in selective detection toward BTEX using resonator-type gas sensors. Gas sensing results toward toluene in different relative humidities show that the new-style sensor has stable toluene/water selective detection performance and that the disturbance of water is negligible. Besides, the limit of detection toward toluene of the sensor is lower than the odor threshold value.

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