Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Mol Immunol ; 160: 95-102, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37413911

RESUMO

Despite the wide usage of ß2-adrenoceptor agonists in asthma treatment, they do have side effects such as aggravating inflammation. We previously reported that isoprenaline induced Cl- secretion and IL-6 release via cAMP-dependent pathways in human bronchial epithelia, but the mechanisms underlying the inflammation-aggravation effects of ß2-adrenoceptor agonists remain pooly understood. In this study, we investigated formoterol, a more specific ß2-adrenoceptor agonist, -mediated signaling pathways involved in the production of IL-6 and IL-8 in 16HBE14o- human bronchial epithelia. The effects of formoterol were detected in the presence of PKA, exchange protein directly activated by cAMP (EPAC), cystic fibrosis transmembrane conductance regulator (CFTR), extracellular signal-regulated protein kinase (ERK)1/2 and Src inhibitors. The involvement of ß-arrestin2 was determined using siRNA knockdown. Our results indicate that formoterol can induce IL-6 and IL-8 secretion in concentration-dependent manner. The PKA-specific inhibitor, H89, partially inhibited IL-6 release, but not IL-8. Another intracellular cAMP receptor, EPAC, was not involved in either IL-6 or IL-8 release. PD98059 and U0126, two ERK1/2 inhibitors, blocked IL-8 while attenuated IL-6 secretion induced by formoterol. Furthermore, formoterol-induced IL-6 and IL-8 release was attenuated by Src inhibitors, namely dasatinib and PP1, and CFTRinh172, a CFTR inhibitor. In addition, knockdown of ß-arrestin2 by siRNA only suppressed IL-8 release when a high concentration of formoterol (1 µM) was used. Taken together, our results suggest that formoterol stimulates IL-6 and IL-8 release which involves PKA/Src/ERK1/2 and/or ß-arrestin2 signaling pathways.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Interleucina-8 , Humanos , Fumarato de Formoterol/farmacologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Interleucina-8/metabolismo , Interleucina-6/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Inflamação , RNA Interferente Pequeno , Receptores Adrenérgicos/metabolismo
2.
PLoS One ; 16(3): e0247578, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33711032

RESUMO

To select the optimum fertilizer application under specific irrigation levels and to provide a reliable fertigation system for tomato plants, an experiment was conducted by using a microporous membrane for water-fertilizer integration under non-pressure gravity. A compound fertilizer (N:P2O5:K2O, 18:7:20) was adopted for topdressing at four levels, 1290 kg/ha, 1140 kg/ha, 990 kg/ha, and 840 kg/ha, and the locally recommended level of 1875 kg/ha was used as the control to explore the effects of different fertilizer application rates on growth, nutrient distribution, quality, yield, and partial factor of productivity (PFP) in tomato. The new regime of microporous membrane water-fertilizer integration under non-pressure gravity irrigation reduced the fertilizer application rate while promoting plant growth in the early and intermediate stages. Except for the 990 kg/ha fertilizer treatment, yields per plant and per plot for each fertilizer application rate were higher than or equal to those of the control. The new regime could effectively improve PFP and reduce soil nutrient enrichment. Fertilizer at 840 kg/ha showed the optimum results by increasing PFP by 75.72% as compared to control. In conclusion, the fertilizer rate at 840 kg/ha has not only maintained the productivity of soil but also tomato growth and quality of fruit which makes the non-pressure gravity irrigation a potential and cost-effective way for fertilizer application.


Assuntos
Irrigação Agrícola/métodos , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes , Frutas/química , Frutas/crescimento & desenvolvimento , Valor Nutritivo , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Gravitação , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Solo/química , Solubilidade , Água/química
3.
Ying Yong Sheng Tai Xue Bao ; 31(8): 2630-2636, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34494785

RESUMO

We explored the effects of sub-low temperature and drought on water transport in tomato seedlings under normal temperature (25 ℃ day/18 ℃ night) and sub-low temperature (15 ℃ day/8 ℃ night) within the artificial climate chamber, and under normal irrigation (75%-85% field water holding capacity) and drought treatment (55%-65% field water holding capacity). We analyzed the effects of temperature and soil moisture on water transport, stomata and xylem vessel morpholo-gical and anatomical structure of tomato plants. The results showed that compared with condition of normal temperature + normal irrigation, drought treatment significantly reduced leaf water potential, transpiration rate, stomatal conductance, hydraulic conductance, sap flow rate, stomatal length, and diameter of leaf, stem and root conduit, and thus thickened the cell wall and enhanced the anti-embolism ability of conduit in leaf, stem and root. Leaf water potential, transpiration rate, stomatal conductance, hydraulic conductance, and conduit diameter in leaf, stem and root were significantly reduced by sub-low temperature treatment, but the stomata became larger, cell wall was thickened and the anti-embolism ability was enhanced in leaf, stem and root conduit. Under sub-low temperature condition, soil moisture did not affect leaf water potential, transpiration rate, stomatal conductance, hydraulic conductance, stomatal morphology, conduit structure of leaf and root. In conclusion, under drought treatment, the homeostasis in water relationship was obtained by the coordination of leaf, stem and root structure. Under sub-low temperature treatment, the regulation of water relationship was mainly dependent on the changes of conduit structure in leaf and root, which was less affected by soil moisture.


Assuntos
Transpiração Vegetal , Solanum lycopersicum , Secas , Folhas de Planta , Estômatos de Plantas , Solo , Temperatura , Água
4.
Ying Yong Sheng Tai Xue Bao ; 31(7): 2422-2430, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32715709

RESUMO

A field experiment with five treatments, control (CK, no fertilizer), conventional fertilization (U), double-effect inhibitor synergistic urea (DU), coated urea (CU) and slow/controlled release urea mixture (CDU), was conducted to investigate the effects of conventional fertilization (240 kg N·hm-2) and one-off application of different slow/controlled release fertilizers (180 kg N·hm-2) on the yield and quality of fresh maize, soil inorganic nitrogen (N), and ammonia (NH3) emissions. The results showed that the total amount of ammonia volatilization was the highest in treatment of conventional fertilization (U), with N topdressing being an important source of NH3 emission. Compared with U treatment, the NH3 volatilization in the DU, CU, and CDU treatments was reduced by 78%-81%. At harvest stage, the soil layer of 80-100 cm in the U treatment had the highest nitrate concentration (51.6 mg·kg-1), resulting in a high risk of N leaching. In contrast, the nitrate concentrations in the same soil layer in the slow/controlled release fertilizer treatments were much lower, reducing the risk of leaching. In comparison with U, three slow/controlled release fertilizer treatments with 25% lower N application did not decrease yield but increased seed Vc, soluble sugar and protein contents. The agronomic efficiency and economic benefit of DU treatment were the highest among three slow/controlled release fertilizers treatments. In conclusion, the application of new type of slow/controlled release fertilizer could improve the yield and quality of fresh maize, and significantly reduce the risk of ammonia loss and N leaching. Considering the higher cost of the polymer coated urea, the double-effect inhibitor urea has lower cost and is more convenient to make. It is therefore a better choice to fresh maize planting.


Assuntos
Amônia/análise , Fertilizantes/análise , Agricultura , Preparações de Ação Retardada , Nitrogênio , Solo , Zea mays
5.
J Phys Condens Matter ; 31(20): 205501, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-30708355

RESUMO

The ferromagnetism of the two dimensional (2D) Cr2Ge2Te6 atomic layers with the perpendicular magnetic anisotropy and the Curie temperature 30-50 K has recently been experimentally confirmed. By performing the density-functional theory calculations, we demonstrate that the magnetic properties of bilayer Cr2Ge2Te6 can be flexibly tailored, due to the effective band structure tuning by the external electric field. The electric field induces the semiconductor-metal transition and redistributes charge and spin between the two layers. Furthermore, the magnetic anisotropy energy of the bilayer Cr2Ge2Te6 can be obviously enhanced by the electric field, which is helpful to stabilize the long-range ferromagnetic order. Our study about the electric manipulation of magnetism based on the band structure engineering generally exists in 2D magnetic systems and will be of great significance in low-dimensional all-electric spintronics.

6.
ACS Appl Mater Interfaces ; 10(14): 11663-11670, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29546985

RESUMO

Layered LiNi1/3Co1/3Mn1/3O2 (NCM333) is successfully coated by fast ionic conductor LiTi2(PO4)3 (LTP) via a wet chemical method. The effects of LTP on the physicochemical properties and electrochemical performance are studied. The results reveal that a highly layered structure of NCM333 can be well maintained with less cation mixing after LTP coating. LTP of about 5 nm thickness is coated on the surface of NCM333. Such an LTP coating layer can effectively suppress the side reactions between NCM333 and electrolyte but will not hinder the lithium ion transmission. As a result, LTP-coated NCM333 owns an improved capability and cyclic performance, for example, NCM333/LTP delivers an initial capacity as high as 121.0 mA h g-1 with a capacity retention ratio of 82.3% after 200 cycles at 10 C, whereas NCM333 only has an initial capacity of 120.4 mA h g-1 with a very low capacity retention ratio of 66.4%. This method of using a fast ionic conductor like LTP as a coating material may provide a simple and effective strategy to modify those electrode materials with poor cyclic performance.

7.
ACS Appl Mater Interfaces ; 9(49): 42788-42796, 2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29155556

RESUMO

In this study, low cost anthracite-derived dual-phase carbon-coated Li3V2(PO4)3 composites have been successfully prepared via a traditional solid-phase method. XRD results show that the as-prepared samples have high crystallinity and anthracite introduction has no influence on the LVP crystal structure. The LVP/C particles are uniformly covered with a dual-phase carbon layer composed of amorphous carbon and graphitic carbon. The effect of the amount of anthracite on the battery performance of LVP as a cathode material has also been studied. The LVP/C composite obtained with 10 wt % anthracite (LVP/C-10) delivers the highest initial charge/discharge capacities of 186.1/168.2 mAh g-1 at 1 C and still retains the highest discharge capacity of 134.0 mAh g-1 even after 100 cycles. LVP/C-10 also displays an outstanding average capacity of 140.8 mAh g-1 at 5 C. The superior rate capability and cycling stability of LVP/C-10 is ascribed to the reduced particle size, decreased charge-transfer resistance, and improved lithium ion diffusion coefficient. Our results demonstrate that using anthracite as a carbon source opens up a new strategy for larger-scale synthesis of LVP and other electrode materials with poor electronic conductivity for lithium ion batteries.

8.
Nanoscale ; 9(45): 17957-17962, 2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29125168

RESUMO

GeTe is a prototypical compound of a new class of multifunctional materials, i.e., ferroelectric Rashba semiconductors (FRS). In the present work, by combining the first-principles calculations and Rashba model analysis, we reexamine Rashba spin-orbit coupling (SOC) in a GeTe(111) crystal and clarify its linear Rashba SOC strength. We further investigate Rashba SOC at the interface of a GeTe(111)/InP(111) superlattice and demonstrate the ferroelectric manipulation of Rashba SOC in detail. A large modulation of Rashba SOC is obtained, and surprisingly, we find that Rashba SOC does not monotonically increase with the increase of ferroelectric displacement, due to the parabola opening reversal of Rashba splitting bands. In addition, a reversal of the spin texture is realized by tuning the ferroelectric polarization. Our investigation provides a deep insight into the ferroelectric control of Rashba SOC, which is of great importance in FRS spin field effect transistors.

9.
J Environ Sci (China) ; 17(4): 572-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16158581

RESUMO

Heavy metal distribution in the specialized accumulating plants was important for phytoextraction technique. Hydroponic and pot experiment were conducted to investigated Cd phytoextraction ability and Cd distribution in the plant of oilseed rape species. The results showed that oilseed rape Chuanyou II-10 was more effective in phytoexetraction Cd among 21 varieties of oilseed rape and indicator plant Indian mustard. Cd concentration in the shoot of Chuanyou 11-10 and Indian mustard gradually decreased with an increase in growth period, while the amount of Cd uptake increased with the increase of growth period. There was constantly decrease in Cd concentration from the base leaves to the top leaves of Chuanyou II-10 and Indian mustard, the percentages of Cd uptake in older leaves were higher than those of younger leaves. Older leaves of Chuanyou 11-10 and Indian mustard extracted more Cd for the Cd contamination soil, leaves should as far as possible develop before they reached the soil and the older leaves were harvested in priority.


Assuntos
Cádmio/química , Mostardeira/química , Óleos de Plantas/química , Poluentes do Solo , Ácidos Graxos Monoinsaturados , Mostardeira/crescimento & desenvolvimento , Óleo de Brassica napus
10.
J Environ Sci (China) ; 16(4): 594-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15495963

RESUMO

Two pot experiments were conducted under greenhouse conditions to investigate the characteristics of Cd uptake and accumulation by two Cd accumulator oilseed rape varieties and one Indian mustard grown on a loamy soil that had been artificially contaminated by different amounts of CdSO4 (0, 20, 40, 60, 80, 100 mg/kg soil). The relationship between shoot Cd uptake of the two oilseed rape cultivars and the soil Cd concentrations could be simulated via quadratic equations. The curve showed that maximum shoot Cd uptake of Indian mustard was 314.7 microg/pot at soil Cd concentration of 87.8 mg/kg, while maximum uptake of the variety Xikou Huazi was 543.3 microg/pot at soil Cd concentration of 69.1 mg/kg and that of the variety Zhongyou Za-1hao was 576.7 microg/pot at soil Cd concentration of 84.0 mg/kg, suggesting that shoot Cd uptake ability of the two Cd accumulator oilseed rapes was significantly higher than that of the Indian mustard. Xikou Huazi had higher phytoremediation potential for Cd contaminated soil. Shoot Cd accumulation ability of the two Cd accumulator oilseed rapes was correspond and Cd was easier translocated to the shoot than hyperaccumulator Indian mustard as comparation plant. Shoot Cd distribution pattern showed consistent and significant reduction from older leaves to younger ones of two oilseed rapes and Indian mustard. Cd uptake by oilseed rapes in growth prophase was higher than that of growth anaphase.


Assuntos
Brassicaceae/química , Cádmio/farmacocinética , Poluentes do Solo/farmacocinética , Biodegradação Ambiental , Brassicaceae/crescimento & desenvolvimento , Raízes de Plantas , Distribuição Tecidual
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa