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1.
Arch Virol ; 163(12): 3317-3325, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30220033

ABSTRACT

Porcine reproductive and respiratory syndrome virus (PRRSV) is a pathogen that severely disrupts swine production. Despite sustained efforts, the disease is still endemic, with high mortality and morbidity. New antiviral strategies to control PRRSV are needed. Griffithsin, a red algal lectin, has potent antiviral effect on several human enveloped viruses, but this effect has not been demonstrated on PRRSV. Here, we first tested the in vitro antiviral activity of Griffithsin against PRRSV. Griffithsin exerted strong saccharide-dependent antiviral activity against PRRSV, probably through interactions with glycans on the surface of PRRSV that interfered with virus entry. Furthermore we revealed that Griffithsin's action on PRRSV involved blocking viral adsorption, and it had no effect on viral penetration. Besides Our findings also suggested that Griffithsin may interfere with cell-to-cell spread to prevent virus transmission. The remarkable potency profile of Griffithsin supports its potential value as an antiviral agent against PRRSV.


Subject(s)
Antiviral Agents/pharmacology , Plant Lectins/pharmacology , Porcine Reproductive and Respiratory Syndrome/virology , Porcine respiratory and reproductive syndrome virus/drug effects , Porcine respiratory and reproductive syndrome virus/physiology , Animals , Porcine Reproductive and Respiratory Syndrome/drug therapy , Porcine respiratory and reproductive syndrome virus/genetics , Swine , Virus Internalization/drug effects , Virus Replication/drug effects
2.
Small Methods ; : e2400565, 2024 Jun 23.
Article in English | MEDLINE | ID: mdl-38923872

ABSTRACT

This work utilizes defect engineering, heterostructure, pyridine N-doping, and carbon supporting to enhance cobalt-nickel selenide microspheres' performance in the oxygen electrode reaction. Specifically, microspheres mainly composed of CoNiSe2 and Co9Se8 heterojunction rich in selenium vacancies (VSe·) wrapped with nitrogen-doped carbon nanotubes (p-CoNiSe/NCNT@CC) are prepared by Ar/NH3 radio frequency plasma etching technique. The synthesized p-CoNiSe/NCNT@CC shows high oxygen reduction reaction (ORR) performance (half-wave potential (E1/2) = 0.878 V and limiting current density (JL) = 21.88 mA cm-2). The JL exceeds the 20 wt% Pt/C (19.34 mA cm-2) and the E1/2 is close to the 20 wt% Pt/C (0.881 V). It also possesses excellent oxygen evolution reaction (OER) performance (overpotential of 324 mV@10 mA cm-2), which even exceeds that of the commercial RuO2 (427 mV@10 mA cm-2). The density functional theory calculation indicates that the enhancement of ORR performance is attributed to the synergistic effect of plasma-induced VSe· and the CoNiSe2-Co9Se8 heterojunction. The p-CoNiSe/NCNT@CC electrode assembled Zinc-air batteries (ZABs) show a peak power density of 138.29 mW cm-2, outperforming the 20 wt% Pt/C+RuO2 (73.9 mW cm-2) and other recently reported catalysts. Furthermore, all-solid-state ZAB delivers a high peak power density of 64.83 mW cm-2 and ultra-robust cycling stability even under bending.

3.
Nanomicro Lett ; 16(1): 250, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023812

ABSTRACT

This work reports the use of defect engineering and carbon supporting to achieve metal-doped phosphides with high activities and stabilities for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in alkaline media. Specifically, the nitrogen-doped carbon nanofiber-supported Ni-doped CoP3 with rich P defects (Pv·) on the carbon cloth (p-NiCoP/NCFs@CC) is synthesized through a plasma-assisted phosphorization method. The p-NiCoP/NCFs@CC is an efficient and stable catalyst for the HER and the OER. It only needs overpotentials of 107 and 306 mV to drive 100 mA cm-2 for the HER and the OER, respectively. Its catalytic activities are higher than those of other catalysts reported recently. The high activities of the p-NiCoP/NCFs@CC mainly arise from its peculiar structural features. The density functional theory calculation indicates that the Pv· richness, the Ni doping, and the carbon supporting can optimize the adsorption of the H atoms at the catalyst surface and promote the strong electronic couplings between the carbon nanofiber-supported p-NiCoP with the surface oxide layer formed during the OER process. This gives the p-NiCoP/NCFs@CC with the high activities for the HER and the OER. When used in alkaline water electrolyzers, the p-NiCoP/NCFs@CC shows the superior activity and excellent stability for overall water splitting.

4.
Materials (Basel) ; 16(15)2023 Jul 27.
Article in English | MEDLINE | ID: mdl-37569969

ABSTRACT

Secondary aluminum ash is a kind of common solid waste which will pollute the environment without any treatment. In this study, the influence of secondary aluminum ash on the rheological properties and the initial setting time of fresh reactive powder concrete (RPC) are researched. Meanwhile, the mechanical properties and the drying shrinkage rates of RPC with the secondary aluminum ash are determined. The electrical parameters of RPC with the secondary aluminum ash are measured. Scanning electron microscopy is obtained to reflect the internal structure of RPC. Results show that the addition of secondary aluminum ash can lead to decreasing the fluidity and increase the yield shear stress of fresh RPC paste by varying rates of 16.1% and 58.3%, respectively. The addition of secondary aluminum ash can decrease the flexural and compressive strengths of RPC cured for 1 day by the decreasing rates of 0~18.7% and 0~19.3%. When the curing age is 28 days, the flexural and compressive strengths of RPC are increased by 0~9.1% and 0~19.1% with adding the secondary aluminum ash. The secondary aluminum ash can promote the condensation of RPC. The addition of the secondary aluminum ash can decrease the electrical resistance of RPC by an order of magnitude. The relationship between the electrical resistance and the electrical reactance fits the quadratic function equation. The electrical resistance of the pore solution increases in the form of a quadratic function with the mass ratio of the secondary aluminum ash. The dry shrinkage rates of RPC cured for 1 day and 28 days are decreased by 0~36.4% and 0~41.3% with the increasing dosages of secondary aluminum ash. As obtained from the microscopic testing results, the secondary aluminum ash can improve the compactness of hydration products.

5.
J Colloid Interface Sci ; 649: 36-48, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37331108

ABSTRACT

Developing high-efficient, good-durability, and low-cost bifunctional non-precious metal catalysts for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is urgent and significant for promoting the practical rechargeable zinc-air batteries (RZABs). Herein, N-doped carbon coated Co/FeCo@Fe(Co)3O4 heterojunction rich in oxygen vacancies derived from metal-organic frameworks (MOFs) is successfully constructed by O2 plasma treatment. The phase transition of Co/FeCo to FeCo oxide (Fe3O4/Co3O4) mainly occurs on the surface of nanoparticles (NPs) during the O2 plasma treatment, which can form rich oxygen vacancies simultaneously. The fabricated catalyst P-Co3Fe1/NC-700-10 with optimal O2 plasma treatment time of 10 min can reduce the potential gap between the OER and ORR to 760 mV, which is much lower than commercial 20% Pt/C + RuO2 (910 mV). Density functional theory (DFT) calculation indicates that the synergistic coupling between Co/FeCo alloy NPs and FeCo oxide layer can promote the ORR/OER performance. Both liquid electrolyte RZAB and flexible all-solid-state RZAB using P-Co3Fe1/NC-700-10 as the air-cathode catalyst display high power density, specific capacity and excellent stability. This work provides an effective idea for the development of high performance bifunctional electrocatalyst and the application of RZABs.

6.
Adv Sci (Weinh) ; 8(10): 2004572, 2021 May.
Article in English | MEDLINE | ID: mdl-34026452

ABSTRACT

This work reports a novel approach for the synthesis of FeCo alloy nanoparticles (NPs) embedded in the N,P-codoped carbon coated nitrogen-doped carbon nanotubes (NPC/FeCo@NCNTs). Specifically, the synthesis of NCNT is achieved by the calcination of graphene oxide-coated polystyrene spheres with Fe3+, Co2+ and melamine adsorbed, during which graphene oxide is transformed into carbon nanotubes and simultaneously nitrogen is doped into the graphitic structure. The NPC/FeCo@NCNT is demonstrated to be an efficient and durable bifunctional catalyst for oxygen evolution (OER) and oxygen reduction reaction (ORR). It only needs an overpotential of 339.5 mV to deliver 10 mA cm-2 for OER and an onset potential of 0.92 V to drive ORR. Its bifunctional catalytic activities outperform those of the composite catalyst Pt/C + RuO2 and most bifunctional catalysts reported. The experimental results and density functional theory calculations have demonstrated that the interplay between FeCo NPs and NCNT and the presence of N,P-codoped carbon structure play important roles in increasing the catalytic activities of the NPC/FeCo@NCNT. More impressively, the NPC/FeCo@NCNT can be used as the air-electrode catalyst, improving the performance of rechargeable liquid and flexible all-solid-state zinc-air batteries.

7.
Chem Biol Interact ; 309: 108706, 2019 Aug 25.
Article in English | MEDLINE | ID: mdl-31194955

ABSTRACT

Oxidative-stress-induced osteoblast dysfunction plays an important role in the development and progression of osteoporosis. BTB and CNC homology 1 (Bach1) has been suggested as a critical regulator of oxidative stress; however, whether Bach1 plays a role in regulating oxidative-stress-induced osteoblast dysfunction remains unknown. Thus, we investigated the potential role and mechanism of Bach1 in regulating oxidative-stress-induced osteoblast dysfunction. Osteoblasts were treated with hydrogen peroxide (H2O2) to mimic a pathological environment for osteoporosis in vitro. H2O2 exposure induced Bach1 expression in osteoblasts. Functional experiments demonstrated that Bach1 silencing improved cell viability and reduced cell apoptosis and reactive oxygen species (ROS) production in H2O2-treated cells, while Bach1 overexpression produced the opposite effects. Notably, Bach1 inhibition upregulated alkaline phosphatase activity and osteoblast mineralization. Mechanism research revealed that Bach1 inhibition increased the activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling and upregulated heme oxygenase 1 and NAD(P)H:quinone oxidoreductase 1 mRNA expression. The Bach1 inhibition-mediated protective effect was partially reversed by silencing Nrf2 in H2O2-exposed osteoblasts. Taken together, these results demonstrate that Bach1 inhibition alleviates oxidative-stress-induced osteoblast apoptosis and dysfunction by enhancing Nrf2/ARE signaling activation, findings that suggest a critical role for the Bach1/Nrf2/ARE regulation axis in osteoporosis progression. Our study suggests that Bach1 may serve as a potential therapeutic target for treating osteoporosis.


Subject(s)
Antioxidant Response Elements/genetics , Basic-Leucine Zipper Transcription Factors/metabolism , Hydrogen Peroxide/pharmacology , NF-E2-Related Factor 2/metabolism , Oxidative Stress/drug effects , Signal Transduction/drug effects , Animals , Apoptosis/drug effects , Basic-Leucine Zipper Transcription Factors/antagonists & inhibitors , Basic-Leucine Zipper Transcription Factors/genetics , Cell Differentiation/drug effects , Cell Line , Cell Survival/drug effects , Down-Regulation , Mice , NF-E2-Related Factor 2/antagonists & inhibitors , NF-E2-Related Factor 2/genetics , Osteoblasts/cytology , Osteoblasts/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Reactive Oxygen Species/metabolism
8.
RSC Adv ; 8(26): 14462-14472, 2018 Apr 17.
Article in English | MEDLINE | ID: mdl-35540762

ABSTRACT

A composite with a hierarchical structure consisting of nitrogen doped carbon nanosheets with the deposition of nitrogen doped carbon coated Co-CoO nanoparticles (Co-CoO@NC/NC) has been synthesized by a simple procedure involving the drying of the reaction mixture containing Co(NO3)2, glucose, and urea and its subsequent calcination. The drying step is found to be necessary to obtain a sample with small and uniformly sized Co-CoO nanoparticles. The calcination temperature has a great effect on the catalytic activity of the final product. Specifically, the sample prepared at the calcination temperature of 800 °C shows better catalytic activity of the oxygen reduction reaction (ORR). Urea in the reaction mixture is crucial to obtain the sample with the uniformly sized Co-CoO nanoparticles and also plays an important role in improving the catalytic activity of the Co-CoO@NC/NC. Additionally, there exists a strong electronic interaction between the Co-CoO nanoparticles and the NC. Most interestingly, the Co-CoO@NC/NC is highly efficient for the ORR and can deliver an ORR onset potential of 0.961 V vs. RHE and a half-wave potential of 0.868 V vs. RHE. Both the onset and half-wave potentials are higher than those of most catalysts reported previously and even close to those of the commercial Pt/C (the ORR onset and half-wave potential of the Pt/C are 0.962 and 0.861 V vs. RHE, respectively). This, together with its high stability, strongly suggests that the Co-CoO@NC/NC could be used as an efficient catalyst for the ORR.

9.
J Colloid Interface Sci ; 511: 119-127, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29017097

ABSTRACT

A facile template-free Ostwald ripening method is developed for the preparation of the reduced graphene oxide supported splode-like NiCo2O4 hollow microsphere (SNHM/rGO). The graphene oxide used in the reaction mixture is found to play a crucial role in the formation of the SNHM/rGO. It promotes the formation of the NiCo-glycerol microspheres suitable for the Ostwald ripening to form the reduced graphene oxide supported hollow NiCo-glycerol microspheres, which is important for the subsequent calcination to form the SNHM/rGO. The obtained SNHM/rGO shows a great promise as the anode for lithium-ion batteries and can deliver a stable reversible capacity of 1048.1 mA h g-1 at the current density of 100 mA g-1. The performance of the SNHM/rGO is much higher than that of most NiCo2O4-based materials reported previously, strongly suggesting that the SNHM/rGO could be used as the anode for practical applications. This is well supported by the higher performance of the LiCoO2//SNHM-rGO full cell. The excellent electrochemical performance can be attributed to the specific structure of the SNHM/rGO, which comprises the splode-like hollow NiCo2O4 microspheres with the reduced graphene oxide integrated.

10.
PLoS One ; 12(5): e0176965, 2017.
Article in English | MEDLINE | ID: mdl-28475649

ABSTRACT

The activity of Schwann cells (SWCs) is very important in trauma-induced nerve repair, and tumour necrosis factor-α (TNF-α) produced during tissue injury inhibits the viability of SWCs, which delays the repair of peripheral nerves. Loganin is an iridoid glycoside that has been shown to alleviate a variety of cytotoxic effects. In the current study, we evaluated the potential efficacy and the mechanism of action of loganin in TNF-α-induced cytotoxicity in SW10 cells. The experimental results indicated that loganin blocked TNF-α-mediated Smad2 activation, downregulated the expression of the G1 phase cell cycle inhibitor p15IN4KB, and upregulated the expression of the G1 phase cell cycle activator cyclin D1-CDK4/6, which upregulated E2F-1-dependent survivin expression and relieved TNF-α-induced apoptosis in SW10 cells. The protective effect of loganin on SWCs has potential medicinal value in the promotion of peripheral nerve repair and is significant for studies in the field of tissue regeneration.


Subject(s)
Cell Cycle Checkpoints/drug effects , Iridoids/pharmacology , Signal Transduction/drug effects , Smad2 Protein/metabolism , Tumor Necrosis Factor-alpha/physiology , Apoptosis/drug effects , Cell Cycle Checkpoints/physiology , Cell Line , E2F1 Transcription Factor/metabolism , Humans , Inhibitor of Apoptosis Proteins/metabolism , Real-Time Polymerase Chain Reaction , Survivin
11.
ACS Appl Mater Interfaces ; 9(23): 20046-20056, 2017 Jun 14.
Article in English | MEDLINE | ID: mdl-28535030

ABSTRACT

Sulfonated holey graphene oxides (SHGOs) have been synthesized by the etching of sulfonated graphene oxides with concentrated HNO3 under the assistance of ultrasonication. These SHGOs could be used as fillers for the sulfonated aromatic poly(ether ether ketone) (SPEEK) membrane. The obtained SHGO-incorporated SPEEK membrane has a uniform and dense structure, exhibiting higher performance as proton exchange membranes (PEMs), for instance, higher proton conductivity, lower activation energy for proton conduction, and comparable methanol permeability, as compared to Nafion 112. The sulfonated graphitic structure of the SHGOs is believed to be one of the crucial factors resulting in the higher performance of the SPEEK/SHGO membrane, since it could increase the local density of the -SO3H groups in the membrane and induce a strong interfacial interaction between SHGO and the SPEEK matrix, which improve the proton conductivity and lower the swelling ratio of the membrane, respectively. Additionally, the proton conductivity of the membrane could be further enhanced by the presence of the holes in the graphitic planes of the SHGOs, since it provides an additional channel for transport of the protons. When used, direct methanol fuel cell with the SPEEK/SHGO membrane is found to exhibit much higher performance than that with Nafion 112, suggesting potential use of the SPEEK/SHGO membrane as the PEMs.

12.
Gene ; 610: 1-8, 2017 Apr 30.
Article in English | MEDLINE | ID: mdl-28130056

ABSTRACT

MicroRNAs have emerged as important regulators of osteoclast differentiation in recent years. Of these, miR-34c has been reported to play an important role in bone development. However, its role and the underlying mechanism in osteoclast differentiation remains poorly understood. In this study, we aimed to investigate the precise role and molecular mechanism of miR-34c in osteoclast differentiation. We found an obvious increase in miR-34c expression during osteoclast differentiation in osteoclast precursors induced by receptor activator of nuclear factor κB (NF-κB) ligand and macrophage colony-stimulating factor in vitro. Further experiments showed that overexpression of miR-34c significantly promoted osteoclast differentiation while suppression of miR-34c showed the opposite effect. Interestingly, bioinformatics analysis and dual-luciferase reporter assays showed that miR-34c targets the 3'-untranslated region of leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4). The expression of LGR4 was regulated by miR-34c in osteoclasts. Moreover, miR-34c regulated NF-κB and glycogen synthase kinase 3-ß signaling during osteoclast differentiation. Overexpression of LGR4 partially reversed the promoting effect of miR-34c overexpression on osteoclast differentiation. Taken together, our study suggests that miR-34c contributes to osteoclast differentiation by targeting LGR4, providing novel insights into understanding the molecular mechanism underlying osteoclast differentiation.


Subject(s)
Cell Differentiation , MicroRNAs/metabolism , Osteoclasts/cytology , Receptors, G-Protein-Coupled/genetics , 3' Flanking Region , Animals , Male , Mice , Mice, Inbred C57BL , NF-kappa B/metabolism , RAW 264.7 Cells
13.
ACS Appl Mater Interfaces ; 7(34): 19398-407, 2015 Sep 02.
Article in English | MEDLINE | ID: mdl-26277927

ABSTRACT

Boron and nitrogen codoped hollow graphene microspheres (NBGHSs), synthesized from a simple template sacrificing method, have been employed as an electrocatalyst for the oxygen reduction reaction (ORR). Because of their specific hollow structure that consists of boron and nitrogen codoped graphene, the NBGHSs can exhibit even high electrocatalytic activity toward ORR than the commercial JM Pt/C 40 wt %. This, along with their higher stability, makes the NBGHSs particularly attractive as the electrocatalyst for the ORR with great potential to replace the commonly used noble-metal-based catalysts.

14.
Bioresour Technol ; 169: 800-803, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25106779

ABSTRACT

In this work, the role of Brønsted acid for furfural production in biomass pyrolysis on supported sulfates catalysts was investigated. The introduction of Brønsted acid was shown to improve the degradation of polysaccharides to intermediates for furfural, which did not work well when only Lewis acids were used in the process. Experimental results showed that CuSO4/HZSM-5 catalyst exhibited the best performance for furfural (28% yield), which was much higher than individual HZSM-5 (5%) and CuSO4 (6%). The optimum reaction conditions called for the mass ratio of CuSO4/HZSM-5 to be 0.4 and the catalyst/biomass mass ratio to be 0.5. The recycled catalyst exhibited low productivity (9%). Analysis of the catalysts by Py-IR revealed that the CuSO4/HZSM-5 owned a stronger Brønsted acid intensity than HZSM-5 or the recycled CuSO4/HZSM-5. Therefore, the existence of Brønsted acid is necessary to achieve a more productive degradation of biomass for furfural.


Subject(s)
Acids/pharmacology , Biomass , Biotechnology/methods , Furaldehyde/metabolism , Hot Temperature , Phosphoric Acids/pharmacology , Sulfuric Acids/pharmacology , Catalysis/drug effects , Copper Sulfate/pharmacology , Zeolites/pharmacology
15.
Zhongguo Zhen Jiu ; 34(1): 61-5, 2014 Jan.
Article in Zh | MEDLINE | ID: mdl-24673061

ABSTRACT

OBJECTIVE: To observe different effects of moxibustion on extracellular potassium ion in acupoint under physiological and pathological status and provide experimental evidence for exploring action mechanism of moxibustion on acupoint local. METHODS: Forty female SD rats were randomly divided into a blank group, a blank-moxibustion group, a model group and a model-moxibustion group, 10 cases in each one. The complete Freund's adjuvant(CFA) was adopted to establish model of adjuvant arthritis (AA) in the model group and model-moxibustion group. No treatment was given in the blank group and model group while moxibustion was applied at "Zusan-li" (ST 36) for 30 min in the blank-moxibustion group and model-moxibustion group. The tissue fluid in "Zusanli" (ST 36) was collected with microdialysis and real-time analyzed by electrolytic analyzer. The change of concentration of potassium ion in "Zusanli" (ST 36) was observed. RESULTS: (1) Under physiological status, the concentration of extracellular potassium ion in the blank group was not changed within 150 min (P > 0.05); before the moxibustion, the concentration of extracellular potassium ion in the blank-moxibustion group was (1.21 +/- 0.31) mmol/L, and after treatment it was gradually increased and reached its peak at (2.38 +/- 0.42) mmol/L after 60 min (P < 0.05), then it was reduced. 150 min after the treatment, concentration of potassium ion was slightly higher than that before moxibustion as well as that in the blank group. The concentration in the blank-moxibustion group at 60 min was statistically significant compared with that in the blank group (P < 0.05). (2) Under pathological status, the concentration of extracellular potassium ion in the model group was not changed within 150 min, differences of which at each time point was not statistically significant (all P > 0.05). Before the moxibustion, the concentration of extracellular potassium ion was (1.09 +/- 0.12) mmol/L in the model-moxibustion group, and it was immediately increased to (1.96 +/- 0.18) mmol/L after moxibustion. 60 min and 90 min after the moxibustion, it still maintained a higher level, which was (1.87 +/- 0.29) mmol/L and (1.59 +/- 0.16) mmol/L respectively (both P < 0.05). The differences of each time point after moxibustion in the model-moxibustion group were statistically significant compared with those in the model group (all P < 0.05). CONCLUSION: The moxibustion could increase the concentration of potassium ion in rat's acupoint local under physiological status but time of effect is short; with moxibustion at "Zusanli" (ST 36) under pathological status, the concentration of local potassium ion is obviously increased and maintains for a long time.


Subject(s)
Acupuncture Points , Arthritis, Experimental/therapy , Moxibustion , Potassium/metabolism , Animals , Arthritis, Experimental/metabolism , Disease Models, Animal , Female , Humans , Rats , Rats, Sprague-Dawley
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