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1.
Nano Lett ; 24(11): 3331-3338, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38457459

RESUMO

1T-MoS2 has become an ideal anode for sodium-ion batteries (SIBs). However, the metastable feature of 1T-MoS2 makes it difficult to directly synthesize under normal conditions. In addition, it easily transforms into 2H phase via restacking, resulting in inferior electrochemical performance. Herein, the electron configuration of Mo 4d orbitals is modulated and the stable 1T-MoS2 is constructed by nickel (Ni) introduction (1T-Ni-MoS2). The original electron configuration of Mo 4d orbitals is changed via the electron injection by Ni, which triggers the phase transition from 2H to 1T phase, thus improving the electrical conductivity and accelerating the redox kinetics of the material. Consequently, 1T-Ni-MoS2 exhibits superior rate capability (266.8 mAh g-1 at 10 A g-1) and excellent cycle life (358.7 mAh g-1 at 1 A g-1 after 350 cycles). In addition, the assembled Na3V2(PO4)3/C||1T-Ni-MoS2 full cells deliver excellent electrochemical properties and show great prospects in energy storage devices.

2.
Small ; : e2312168, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38377284

RESUMO

Hydroxides are the archetype of layered crystals with metal-oxygen (M-O) octahedron units, which have been widely investigated as oxygen evolution reaction (OER) catalysts. However, the better crystallinity of hydroxide materials, the more perfect octahedral symmetry and atomic ordering, resulting in the less exposed metal sites and limited electrocatalytic activity. Herein, a glassy state hydroxide material featuring with short-range order and long-range disorder structure is developed to achieve high intrinsic activity for OER. Specifically, a rapid freezing point precipitation method is utilized to fabricate amorphous multi-component hydroxide. Owing to the freezing-point crystallization environment and chaotic M-O (M = Ni/Fe/Co/Mn/Cr etc.) structures, the as-fabricated NiFeCoMnCr hydroxide exhibit a highly-disordered glassy structure, as-confirmed by X-ray/electron diffraction, enthalpic response, and pair distribution function analysis. The as-achieved glassy-state hydroxide materials display a low OER overpotential of 269 mV at 20 mA cm-2 with a small Tafel slope of 33.3 mV dec-1 , outperform the benchmark noble-metal RuO2 catalyst (341 mV, 84.9 mV dec-1 ) . Operando Raman and density functional theory studies reveal that the glassy state hydroxide converted into disordered active oxyhydroxide phase with optimized oxygen intermediates adsorption under low OER overpotentials, thus boosting the intrinsic electrocatalytic activity.

3.
Inorg Chem ; 63(13): 5773-5778, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38498977

RESUMO

Seawater electrolysis presents a promising avenue for green hydrogen production toward a carbon-free society. However, the electrode materials face significant challenges including severe chlorine-induced corrosion and high reaction overpotential, resulting in low energy conversion efficiency and low current density operation. Herein, we put forward a nanoporous nickel (npNi) cathode with high chlorine corrosion resistance for energy-efficient seawater electrolysis at industrial current densities (0.4-1 A cm-2). With the merits of an electrostatic chlorine-resistant surface, modulated Ni active sites, and a robust three-dimensional open structure, the npNi electrode showed a low hydrogen evolution reaction overpotential of 310 mV and a high electricity-hydrogen conversion efficiency of 59.7% at 400 mA cm-2 in real seawater and outperformed most Ni-based seawater electrolysis cathodes in recent publications and the commercial Ni foam electrode (459 mV, 46.4%) under the same test condition. In situ electrochemical impedance spectroscopy, high-frame-rate optical microscopy, and first-principles calculation revealed that the improved corrosion resistance, enhanced intrinsic activity, and mass transfer were responsible for the lowered electrocatalytic overpotential and enhanced energy efficiency.

4.
J Nanobiotechnology ; 20(1): 183, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35399073

RESUMO

BACKGROUND: Pine wilt disease as a devastating forest disaster result from Bursaphelenchus xylophilus that spread by stem-borers Monochamus alternatus feeding on pine leaves, which has brought inestimable economic losses to the world's forestry due to lack of effective prevention and control measures. In this paper, we put forward a proposal for utilizing nanoHKUST-1 to encapusulate the Pyrethrins II that a nerve agent extracted from plant to control M. alternatus, including toxicity mechanism research, traceable biopesticide monitoring, and environment assessment for the first time. The highly biocompatible nanoHKUST-1 can solve the problems of poor water solubility, easy degradation and low control efficiency of Pyrethrins II. RESULTS: The results illustrated the biopesticide loading efficiency of PthII@HKUST-1 reached 85% and the cumulative release of pH-dependent PthII@HKUST-1 was up to 15 days (90%), and also effectively avoid photodegradation (pH 7.0, retention 60.9%). 50 nm PthII@HKUST-1 made it easily penetrate the body wall of MA larvae and transmit to tissue cells through contact and diffusion. Moreover, PthII@HKUST-1 can effectively enhance the cytotoxicity and utilization of Pyrethrins II, which will provide valuable research value for the application of typical plant-derived nerve agents in the prevention and control of forestry pests. PthII@HKUST-1 as an environmentally friendly nano-pesticide can efficiently deliver Pyrethrins II to the larval intestines and absorbed by the larvae. PthII@HKUST-1 could also be transmitted to the epidemic wood and dead wood at a low concentration (10 mg/L). CONCLUSION: Here we speculate that nanoHKUST-1 will bring new opportunity to research biopesticide inhibition mechanism of different agricultural and forestry pests, which will break through the existing research limitations on development, utilization and traceable monitoring of biopesticide, especially for the study of targeting specific proteins.


Assuntos
Besouros , Praguicidas , Pinus , Piretrinas , Animais , Agentes de Controle Biológico/farmacologia , Larva , Praguicidas/farmacologia , Piretrinas/farmacologia
5.
Zhonghua Nan Ke Xue ; 28(9): 831-836, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-37839010

RESUMO

OBJECTIVE: To re-evaluate the clinical efficacy of Longjintonglin Capsules (LJTL) in the treatment of chronic prostatitis with damp-heat stasis syndrome. METHODS: This multicenter real-world study included 1 352 cases of chronic prostatitis with damp-heat and stagnation syndrome treated with LJTL (3 capsules once, tid, 30 minutes after meals, for 2 four-week courses) in addition to routine treatment. Before and after treatment, we analyzed the NIH-CPSI scores, the scores of Chinese medicine symptom quantitative classification and changes in individual symptom scores, and observed adverse reactions to medication. RESULTS: The total effectiveness rate of LJTL was 93.64%. Compared with the baseline, the NIH-CPSI scores were significantly decreased after treatment (ï¼»24.27 ± 6.04ï¼½ vs ï¼»8.17 ± 4.21ï¼½, P < 0.05), and so were the scores on the pain symptoms (ï¼»9.63 ± 3.65ï¼½ vs ï¼»3.02 ± 2.23ï¼½, P < 0.05), voiding symptoms (ï¼»5.65 ± 2.15ï¼½ vs ï¼»1.62 ± 1.36) and quality of life (ï¼»8.96 ± 2.32ï¼½ vs ï¼»3.16 ± 1.89ï¼½, P < 0.05). The effectiveness rate of LJTL was 95.9% on the Chinese medicine symptom frequent urination, 90.4% on painful urination, and 91.4% scanty dark urine, with a total effectiveness rate of 82.4% - 95.9%, all with statistically significant difference in comparison with the baseline (P < 0.05). CONCLUSION: Longjintonglin Capsules combined with routine treatment can significantly improve the clinical symptoms of chronic prostatitis with damp-heat stasis syndrome, especially effective on the symptoms of frequent urination, painful urination and scanty dark urine. Besides, it recommendable for its antidepressant and antianxiety effects, and the effect of improving the quality of life of the chronic prostatitis patients with damp-heat stasis.


Assuntos
Medicamentos de Ervas Chinesas , Prostatite , Masculino , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Prostatite/diagnóstico , Prostatite/tratamento farmacológico , Temperatura Alta , Qualidade de Vida , Doença Crônica , Resultado do Tratamento , Cápsulas/uso terapêutico
6.
Nanotechnology ; 32(43)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34284357

RESUMO

Design and develop of cost-effective non-enzymatic electrode materials is of great importance for next generation of glucose sensors. In this work, we report a high-performance self-supporting electrode fabricated via direct epitaxial growth of nickel phosphide on Ni foam (Ni2P/NF) for nonenzymatic glucose sensors in alkaline solution. Under the optimal conditions, the uniform Ni2P nanosheets could be obtained with an average thickness of 80 nm, which provides sufficient active sites for glucose molecules. As a consequence, the Ni2P/NF electrode displays superior electrochemistry performances with a high sensitivity of 6375.1µA mM-1cm-2, a quick response about 1 s, a low detection limit of 0.14µM (S/N = 3), and good selectivity and specificity. Benefit from the strong interaction between Ni2P and NF, the Ni2P/NF electrode is also highly stable for long-term applications. Furthermore, the Ni2P/NF electrode is capable of analyzing glucose in human blood serum with satisfactory results, indicating that the Ni2P/NF is a potential candidate for glucose sensing in real life.


Assuntos
Eletrodos , Glucose/análise , Nanoestruturas/química , Níquel/química , Glicemia/análise , Eletroquímica , Humanos
7.
Bull Entomol Res ; 111(5): 579-584, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33998423

RESUMO

Temperature is one of the main factors affecting insect growth, development and reproduction. The effects of temperatures (10, 15, 20, 25 and 30°C) on the development and reproduction of Cinara cedri Mimeur (Hemiptera: Aphidoidea: Lachnidae) fed on Cedrus deodara (Roxb.) G. Don were evaluated in this study. With the increase of temperature from 10 to 30°C, the development duration at different development stages gradually shortened. There was a significant positive correlation between the developmental rates and temperature, following a quadratic regression model. The lower developmental threshold temperature (C) and effective accumulated temperatures (K) for completing a generation were 4.13°C and 263.4 degree-days, respectively. The highest fecundity was observed at 20°C with 25.74 first-instar nymphs/female. Both the highest intrinsic rate of increase (r, 0.11 ± 0.03) and net reproduction rate (R0, 19.06 ± 2.05) were observed at 20°C, whereas the lowest values of r (0.05 ± 0.01) at 10°C and R0 (5.78 ± 0.88) at 30°C were observed. The results suggest that temperature significantly affects the biology of C. cedri and the optimal temperature for its development is 20°C.


Assuntos
Hemípteros/crescimento & desenvolvimento , Temperatura , Animais , Cedrus , Fertilidade/fisiologia , Hemípteros/fisiologia , Estágios do Ciclo de Vida
8.
J Nanobiotechnology ; 18(1): 165, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33168011

RESUMO

BACKGROUND: Trunk-boring pests (TBPs) are an important type of forest pest, TBPs not only feed on the branches and trunks of trees, but also spread quarantine diseases in forests. However, because the larvae of TBPs live inside the trunk and are well concealed, prevention and control are difficult. The lack of effective control methods leads to the death of many trees in forests. In this study, a novel nanopesticide featuring high bioactivity and slow-release properties was developed to control TBPs. Thiacloprid (THI), which is commonly used to control Coleoptera species, was used as a model pesticide. RESULTS: The oleophobic properties of bovine serum albumin (BSA) were exploited to encapsulate the hydrophobic pesticide THI by self-assembly, and the size of the obtained nanoparticles, THI@BSA·NPs, was approximately 23 nm. The loading efficiency reached 70.4%, and THI@BSA·NPs could be released continuously for over 15 days, with the cumulative release reaching 93.5%. The fluorescein isothiocyanate (FITC)-labeled nanoparticles were evenly distributed in the digestive tract and body surface of a typical TBPs, M. alternatus, and the stomach and contact toxicities increased by 33.7% and 25.9%, respectively, compared with those of free THI. Furthermore, the results showed that the transport efficiency of THI@BSA·NPs was highest at a concentration of 50 µg/mL, and the THI@BSA·NPs content in the trunk, from to lower to higher layers, was 8.8, 8.2, 7.6, and 5.8 µg/g. At the same time, THI@BSA·NPs also exhibited high transport efficiency in dead trees. CONCLUSION: The transport efficiency and toxicity of the active ingredients are the key factors for the control of TBPs. This work provided idea for the application of biological delivery system encapsulated hydrophobic pesticides. The novel self-assembled THI@BSA·NPs have promising potential for sustainable control of TBPs.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Praguicidas/química , Soroalbumina Bovina/química , Animais , Linhagem Celular Tumoral , Larva/efeitos dos fármacos , Nanopartículas/toxicidade , Neonicotinoides/química , Tamanho da Partícula , Praguicidas/toxicidade , Estômago/efeitos dos fármacos , Tiazinas/química , Árvores
9.
Pestic Biochem Physiol ; 143: 147-153, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29183585

RESUMO

Bursaphelenchus xylophilus causes pine wilt disease (PWD), which severely damages pine species. The plant volatile trans­2-hexenal has strong activity against nematodes, although the precise mechanism of this inhibitory action remains unclear. In this paper, the fumigant effects of the LC10 and LC30 of trans­2-hexenal on B. xylophilus were demonstrated. The trans­2-hexenal treatments significantly inhibited the dispersal ability of nematodes. The results also indicated that trans­2-hexenal affects the metabolism of nutrients and the activity of digestive enzymes. Among detoxifying enzymes, after treatment with trans­2-hexenal, glutathione S-transferase activity increased significantly and general esterase activity decreased significantly. Based on these results, trans­2-hexenal disturbs the normal physiological and biochemical activities of this nematode. These results provide valuable insight into the nematicidal mechanisms of trans­2-hexenal.


Assuntos
Aldeídos/toxicidade , Antinematódeos/toxicidade , Tylenchida/efeitos dos fármacos , Animais , Esterases/metabolismo , Glutationa Transferase/metabolismo , Lipase/metabolismo , Peptídeo Hidrolases/metabolismo , Pinus/parasitologia , Caules de Planta/parasitologia , Trealase/metabolismo , Tylenchida/metabolismo , Tylenchida/fisiologia
10.
ChemSusChem ; : e202400713, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785104

RESUMO

Exploring cathode materials with excellent electrochemical performance is crucial for developing rechargeable aqueous zinc ion batteries (RAZIBs). Zinc hexacyanoferrate (ZnHCF), a promising candidate of cathode materials for RAZIBs, suffers from severe electrochemical instability issues. This work reports using low contents of alkaline metal cations as electrolyte additives to improve the cycle performance of ZnHCF. The cations with large sizes, particularly Cs+, changes the intercalation chemistry of ZnHCF in RAZIBs. During cycling, Cs+ cations co-inserted into ZnHCF stabilize the host structure. Meanwhile, a stable phase of CsZn[Fe(CN)6] forms on the ZnHCF cathode, suppressing the loss of active materials through dissolution. ZnHCF gradually converts to an electrochemically inert Zn-rich phase during long-term cycling in aqueous electrolyte, leading to irreversible capacity loss. Introducing Cs+ in the electrolyte inhibits this conversion reaction, resulting in the extended lifespan. Owing to these advantages, the capacity retention rate of ZnHCF/Zn full batteries increases from the original 7.0 % to a high value of 54.6 % in the electrolyte containing 0.03 M of Cs2SO4 after 300 cycles at 0.25 A ⋅ g-1. This research provides an in-depth understanding of the electrochemical behavior of ZnHCF in aqueous zinc electrolyte, beneficial for further optimizing ZnHCF and other metal hexacyanoferrates.

11.
J Colloid Interface Sci ; 662: 986-994, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38387367

RESUMO

Carbon-based supercapacitors have shown great promise for miniaturized electronics and electric vehicles, but are usually limited by their low volumetric performance, which is largely due to the inefficient utilization of carbon pores in charge storage. Herein, we develop a reliable and scalable boric acid templating technique to prepare boron and oxygen co-modified highly-dense yet ultramicroporous carbons (BUMCs). The carbons are featured with high density (up to 1.62 g cm-3), large specific surface area (up to 1050 m2 g-1), narrow pore distribution (0.4-0.6 nm) and exquisite pore surface functionalities (mainly -BC2O, -BCO2, and -COH groups). Consequently, the carbons show exceptionally compact capacitive energy storage. The optimal BUMC-0.5 delivers an outstanding volumetric capacitance of 431 F cm-3 and a high-rate capability in 1 M H2SO4. In particular, an ever-reported high volumetric energy density of 32.6 Wh L-1 can be harvested in an aqueous symmetric supercapacitor. Our results demonstrate that the -BC2O and -BCO2 groups on the ultramicropore walls can facilitate the internal SO42- ion transport, thus leading to an unprecedented high utilization efficiency of ultramicropores for charge storage. This work provides a new paradigm for construction and utilization of dense and ultramicroporous carbons for compact energy storage.

12.
ACS Biomater Sci Eng ; 10(3): 1507-1516, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38372256

RESUMO

Monochamus alternatus is an important stem-boring pest in forestry. However, the complex living environment of Monochamus alternatus creates a natural barrier to chemical control, resulting in a very limited control effect by traditional insecticidal pesticides. In this study, a stable pesticide dendritic mesoporous silica-loaded matrine nanopesticide (MAT@DMSNs) was designed by encapsulating the plant-derived pesticide matrine (MAT) in dendritic mesoporous silica nanoparticles (DMSNs). The results showed that MAT@DMSNs, sustainable nanobiopesticides with high drug loading capacity (80%) were successfully constructed. The release efficiency of DMSNs at alkaline pH was slightly higher than that at acidic pH, and the cumulative release rate of MAT was about 60% within 25 days. In addition, the study on the toxicity mechanism of MAT@DMSNs showed MAT@DMSNs were more effective than MAT and MAT (0.3% aqueous solutions) in touch and stomach toxicity, which might be closely related to their good dispersibility and permeability. Furthermore, MAT@DMSNs are also involved in water transport in trees, which can further transport the plant-derived insecticides to the target site and improve its insecticidal effect. Meanwhile, in addition, the use of essential oil bark penetrants in combination with MAT@DMSNs effectively avoids the physical damage to pines caused by traditional trunk injections and the development of new pests and diseases induced by the traditional trunk injection method, which provides a new idea for the application of biopesticides in the control of stem-boring pests in forestry.


Assuntos
Nanopartículas , Praguicidas , Animais , Matrinas , Dióxido de Silício/farmacologia , Praguicidas/farmacologia , Insetos
13.
Nanoscale ; 15(7): 3345-3350, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722741

RESUMO

Polyanion-type phosphate materials with Na-super-ionic conductor structures are promising for next-generation sodium-ion battery cathodes, although the intrinsically low electroconductivity and limited energy density have restricted their practical applications. In this study, we put forward substituting an inert phosphate with a redox-active silicate to improve the energy density and intrinsic electroconductivity of polyanion-type phosphate materials, thus enabling an advance in sodium-ion battery cathodes. As a proof of concept, some of the phosphate of Na3V2(PO4)3 was replaced by silicate to fabricate Na3V2(PO4)2.9(SiO4)0.1, which exhibited a higher average discharge voltage of 3.36 V and a higher capacity of 115.8 mA h g-1 than pristine Na3V2(PO4)3 (3.31 V, 109.6 mA h g-1) at 0.5 C, therefore improving the energy density. Moreover, the introduced silicate enhanced the intrinsic electroconductivity of Na3V2(PO4)3 materials, as confirmed by both theoretical simulation and electrochemical measurements. After pairing with a commercial hard carbon anode, the optimized Na3V2(PO4)2.9(SiO4)0.1 cathode enabled a stable-cycling full cell with 90.1% capacity retention after 300 cycles at 5 C and a remarkable average coulombic efficiency of 99.88%.

14.
Org Biomol Chem ; 10(1): 36-9, 2012 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21968606

RESUMO

An example of diastereoselective and enantioselective synthesis of thiochroman derivatives through a sulfa-Michael-Michael cascade sequence is disclosed. This is a significant complement of the quinine-thiourea catalyzed sulfa-Michael-Michael cascade reaction. The densely functionalized target thiochromans were obtained in high diastereoselectivities, and with high to excellent enantioselectivities.


Assuntos
Cromanos/química , Alcaloides de Cinchona/química , Catálise , Modelos Moleculares , Estereoisomerismo
15.
Micromachines (Basel) ; 13(7)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35888814

RESUMO

With the development of virtual reality/augmented reality (VR/AR) display devices, the conventional fine metal mask is limited by the wet etch process, which no longer meets the demand for high pixels per inch (PPI) displays. We deposited a layer of magnetic metal on the silicon substrate by physical vapor deposition (PVD), and then developed a 2-inch, 3175 PPI magnetic metal hard mask on silicon substrate (MMS) through deep silicon etching and other micro-nano processing for patterning Organic Light-Emitting Diodes (OLED) displays, which can achieve smaller pixel size and higher PPI. MMS can not only solve the bottleneck problem of the traditional invar alloy shadow mask with low PPI, but also reduce the bending caused by the deformation of the silicon-based mask due to gravity, so that it achieves high PPI and higher uniformity in OLED displays.

16.
Nanomaterials (Basel) ; 12(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35683719

RESUMO

Pine wilt disease is a devastating forest disaster caused by Bursaphelenchus xylophilus, which has brought inestimable economic losses to the world's forestry due to lack of effective prevention and control measures. In this paper, a porous structure CuBTC was designed to deliver avermectin (AM) and a control vector insect Japanese pine sawyer (JPS) of B. xylophilus, which can improve the biocompatibility, anti-photolysis and delivery efficacy of AM. The results illustrated the cumulative release of pH-dependent AM@CuBTC was up to 12 days (91.9%), and also effectively avoided photodegradation (pH 9.0, 120 h, retention 69.4%). From the traceable monitoring experiment, the AM@CuBTC easily penetrated the body wall of the JPS larvae and was transmitted to tissue cells though contact and diffusion. Furthermore, AM@CuBTC can effectively enhance the cytotoxicity and utilization of AM, which provides valuable research value for the application of typical plant-derived nerve agents in the prevention and control of forestry pests. AM@CuBTC as an environmentally friendly nanopesticide can efficiently deliver AM to the larval intestines where it is absorbed by the larvae. AM@CuBTC can be transmitted to the epidemic wood and dead wood at a low concentration (10 mg/L).

17.
J Comput Chem ; 32(8): 1711-20, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21370241

RESUMO

Atomic force fields for simulating copper, silver, and gold clusters and nanoparticles are developed. Potential energy functions are obtained for both monatomic and binary metallic systems using an embedded atom method. Many cluster configurations of varying size and shape are used to constrain the parametrization for each system. Binding energies for these training clusters were computed using density functional theory (DFT) with the Perdew-Wang exchange-correlation functional in the generalized gradients approximation. Extensive testing shows that the many-body potentials are able to reproduce the DFT energies for most of the structures that were included in the training set. The force fields were used to calculate surface energies, bulk structures, and thermodynamic properties. The results are in good agreement with the DFT values and consistent with the available experimental data.

18.
Oncol Lett ; 22(1): 563, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34113391

RESUMO

Circular mitochondrial translation optimization 1 homologue (circMTO1) has been reported to regulate the tumorigenesis of different types of cancer; however, the role of circMTO1 in gallbladder cancer (GBC) remains unknown. The present study aimed to identify the potential miRNAs and target genes of circMTO1 during GBC progression, and clarify the regulatory mechanism between circMTO1 and miRNAs or target genes. The present study performed MTT and Transwell assays, and Annexin V staining to assess cell viability, migration and apoptosis, respectively. In addition, a lymphatic vessel formation assay was performed to assess tube formation of human dermal lymphatic endothelial cells (HDLECs), and GBC-SD and NOZ cells. The results demonstrated that circMTO1 knockdown significantly attenuated the viability and migration of GBC cells and tube formation of HDLECs, and promoted apoptosis, indicating a tumor-promoting role of circMTO1. In addition, transfection with microRNA (miRNA/miR)-219a-5p inhibitor rescued short hairpin RNA-circMTO1-inhibited tumorigenesis of GBC cells, suggesting that miR-219a-5p acts as a downstream effector for circMTO1. Mechanistically, transfection with miR-219a-5p mimic suppressed the expression levels of Smad2/4 and epidermal growth factor receptor. Analysis of The Cancer Genome Atlas datasets revealed that circMTO1 expression was associated with overall survival and the stage of patients with GBC. Taken together, the results of the present study provide novel insight for the role of circMTO1-induced GBC tumorigenesis via regulation of miR-219a-5p expression.

19.
Phys Chem Chem Phys ; 12(33): 9845-51, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20571621

RESUMO

Water dissociation on copper is one of the rate-limiting steps in the water-gas-shift (WGS) reaction. Copper atoms dispersed evenly from freshly made catalyst segregate to form clusters under the WGS operating conditions. Using density functional theory, we have examined water adsorption and dissociation on the smallest stable 3-dimensional copper cluster, Cu(7). Water molecules are adsorbed on the cluster sequentially until full saturation at which no direct water-copper contact is sterically possible. The adsorption is driven mainly by the overlap between the p-orbital of O atom occupied by the lone pair and the 3d-orbitals of copper, from which a fractional charge is promoted to the 4s-orbital to accommodate the charge transfer from water. Water dissociation on the Cu(7) cluster was investigated at both low and high water coverage. It was found that water dissociation into OH and H is exothermic but is inherently a high temperature process at low coverage. At high coverage, the reaction becomes more exothermic with fast kinetics. In both cases, water can catalyze the reaction. It was found that direct dissociation of the OH species is endothermic with a significantly higher barrier at both low and high coverage. However, the OH species can readily react with another adjacent hydroxyl group to form an O adatom and water molecule. Our studies indicate that the basic chemical properties of water dissociative chemisorption may not change significantly with the size of small copper clusters. Similarities between water dissociation on copper clusters and on copper crystalline surfaces are discussed.

20.
Medicine (Baltimore) ; 99(23): e20321, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32501978

RESUMO

BACKGROUND: In recent years, there has been considerable uncertainty about the optimal treatment option for very early hepatocellular carcinoma (HCC) with tumor size less than 2 cm. Therefore, we performed a systematic review and meta-analysis to evaluate the outcomes of the different treatments. METHODS: This study was designed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA). PubMed, EMBASE, and Cochrane library were searched for calculating the survival rates, and the "time to event" method was used to compare the outcomes of liver resection (LR) and radiofrequency ablation (RFA). All studies focusing on the treatment of solitary HCC up to 2 cm by different techniques were included in our analysis. The Hazard ratios (HR) and 95% confidence intervals (CI) derived from multivariate and univariate analysis were utilized to assess the treatment risks. RESULTS: We included 32 studies in our systematic review. The median 5-year overall survival (OS) and recurrence-free survival rate (RFS) for LR were 73% and 47%, respectively, and those for RFA were 73% and 43%, respectively. RFA was found to be associated with increased risk of mortality and recurrence compared to LR (HR = 1.61, 95% CI: 1.35-1.92, P < .0001 for OS and HR = 1.75, 95% CI: 1.56-1.96, P < .0001 for RFS). CONCLUSION: Our meta-analysis demonstrated that LR is superior to RFA in the treatment of solitary HCC up to 2 cm, with reduction in mortality and recurrence risk and improved long-term outcome.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Hepatectomia/métodos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Carcinoma Hepatocelular/mortalidade , Ablação por Cateter/efeitos adversos , Hepatectomia/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Recidiva Local de Neoplasia , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Carga Tumoral
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