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1.
J Psychiatr Res ; 171: 271-276, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38330626

RESUMEN

BACKGROUND: Patients with insomnia are often accompanied by cognitive dysfunction, which seriously affects the quality of life of patients. Repetitive transcranial magnetic stimulation (rTMS) can induce brain neuroplasticity, regulate brain cognitive function and inhibitory control ability. OBJECTIVE: To explore the intervention effect of rTMS on conflict control and sleep quality in patients with insomnia. METHODS: In this single-blind, randomized controlled trial, 39 people with insomnia disorder were randomly divided into real stimulation group and sham stimulation group. The stimulation parameters were stimulation frequency 1 Hz, stimulation intensity 80 % resting motor threshold (RMT), total pulse number 1500 times, time 25 min, and the whole course of treatment lasted 7 days. The Insomnia Severity Index(ISI)、Pittsburgh Sleep Quality Index(PSQI)、Multidimensional Fatigue Inventory(MFI) and Beck Anxiety Inventory(BAI) were assessed at pretest (baseline) and posttest (day 7 after intervention), and the color-word stroop task was used to measure the conflict control ability of the subjects. RESULTS: The sleep quality, correct rate and reaction time of the posttest in the real stimulus group were higher than those in the pretest. However, there was no significant difference between the pretest and posttest in the sham stimulation group. CONCLUSIONS: rTMS stimulation of the left dorsolateral prefrontal cortex (LDLPFC) in patients with insomnia can significantly improve the conflict control ability and sleep quality of patients with insomnia.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Corteza Prefontal Dorsolateral , Calidad de Vida , Método Simple Ciego , Estimulación Magnética Transcraneal/métodos , Corteza Prefrontal , Resultado del Tratamiento
2.
J Bioenerg Biomembr ; 55(5): 325-339, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37584737

RESUMEN

Diabetes can exacerbate myocardial ischemia/reperfusion (IR) injury. However, the sensitivity to IR injury and the underlying mechanisms in diabetic hearts remain unclear. Inhibition of PH domain leucine-rich repeating protein phosphatase (PHLPP1) could reduce myocardial IR injury, our previous study demonstrated that the expression of PHLPP1 was upregulated in diabetic myocardial IR model. Thus, this study aimed to investigate the mechanism of PHLPP1 in diabetic myocardial IR injury. Nondiabetic and diabetic C57BL/6 mice underwent 45 min of coronary artery occlusion followed by 2 h of reperfusion. Male C57BL/6 mice were injected with streptozotocin for five consecutive days to establish a diabetes model. H9c2 cells were exposed to normal or high glucose and subjected to 4 h of hypoxia followed by 4 h of reoxygenation. Diabetes or hyperglycemia increased postischemic infarct size, cellular injury, release of creatine kinase-MB, apoptosis, and oxidative stress, while exacerbating mitochondrial dysfunction. This was accompanied by enhanced expression of PHLPP1 and decreased levels of p-STAT3 and p-Akt. These effects were counteracted by PHLPP1 knockdown. Moreover, PHLPP1 knockdown resulted in an increase in mitochondrial translocation of p-STAT3 Ser727 and nuclear translocation of p-STAT3 Tyr705 and p-STAT3 Ser727. However, the effect of PHLPP1 knockdown in reducing posthypoxic cellular damage was nullified by either Stattic or LY294002. Additionally, a co-immunoprecipitation assay indicated a direct interaction between PHLPP1 and p-STAT3 Ser727, but not p-STAT3 Tyr705. The abnormal expression of PHLPP1 plays a significant role in exacerbating myocardial IR injury in diabetic mice. Knockdown of PHLPP1 to activate the STAT3 signaling pathway may represent a novel strategy for alleviating myocardial IR injury in diabetes.

3.
Langmuir ; 39(11): 4082-4090, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36880180

RESUMEN

Hydrate adhesion is a challenging issue in some practical applications. However, most current anti-hydrate coatings fail to maintain their properties when subject to crude oil and corrosive contaminants. In addition, the effect of surface properties on the nucleation of hydrates is still unexplored from a microscopic perspective. In this study, a multifunctional amphiphobic PF/ZSM-5 coating consisting of 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane modified ZSM-5 zeolite (F/ZSM-5) and adhesive polyethersulfone was fabricated by the spraying method. The interfacial nucleation and adhesion of hydrates on substrates were studied from a microscopic perspective. The coating exhibited excellent repellencies to various liquids, including water, edible oil, liquid paraffin, vacuum pump oil, n-hexadecane, and crude oil. The tetrabutylammonium bromide (TBAB) hydrate is readily nucleated on the bare Cu surface. In contrast, the coated substrate effectively inhibited the hydrate nucleation on the surface and even reduced the adhesion force to 0 mN/m. Furthermore, this coating was fouling- and corrosion-resistant and can maintain an ultralow hydrate adhesion force even after immersion in crude oil or TBAB solution for 20 and 300 d, respectively. The durable anti-hydrate performance of the coating was attributed mainly to the unique architecture and excellent amphiphobic properties enabling stable air cushions between the solid-liquid interface.

4.
Cardiovasc Drugs Ther ; 37(6): 1087-1101, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35715527

RESUMEN

PURPOSE: Ischemic postconditioning (IPostC) alleviates myocardial ischemia/reperfusion (IR) injury, but the protective effect is lost during diabetes. PH domain leucine-rich repeat protein phosphatase 1 (PHLPP1) is able to inactivate Akt. Our previous study found that PHLPP1 expression was upregulated in diabetic hearts. We presumed that the attenuation of myocardial injury by IPostC might be hindered by PHLPP1 overexpression in diabetic animals. METHODS AND RESULTS: Nondiabetic and diabetic mice were subjected to 45 min of ischemia followed by 2 h of reperfusion with or without IPostC. H9c2 cells were exposed to normal or high glucose and were subjected to 4 h of hypoxia followed by 4 h of reoxygenation with or without hypoxic postconditioning (HPostC). IPostC attenuated postischemic infarction, apoptosis, creatine kinase-MB, and oxidative stress, which were accompanied by increased p-Akt and decreased PHLPP1 expression and p-Mst1 in nondiabetic but not in diabetic mice. PHLPP1 knockdown or an Mst1 inhibitor reduced hypoxia/reoxygenation (HR)-induced cardiomyocyte damage in H9c2 cells exposed to normal glucose, but the effect was abolished by a PI3K/Akt inhibitor. HPostC attenuated HR-induced cardiomyocyte injury and oxidative stress accompanied by increased p-Akt as well as decreased PHLPP1 expression and p-Mst1 in H9c2 cells exposed to normal glucose but not high glucose. In addition, HPostC in combination with PHLPP1 knockdown or PHLPP1 knockdown alone reduced cell death and oxidative stress in H9c2 cells exposed to high glucose, which was hindered by PI3K/Akt inhibitor. CONCLUSION: IPostC prevented myocardial IR injury partly through PHLPP1/Akt/Mst1 signaling, and abnormalities in this pathway may be responsible for the loss of IPostC cardioprotection in diabetes.


Asunto(s)
Diabetes Mellitus Experimental , Hiperglucemia , Poscondicionamiento Isquémico , Infarto del Miocardio , Daño por Reperfusión Miocárdica , Ratones , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Repetidas Ricas en Leucina , Infarto del Miocardio/metabolismo , Diabetes Mellitus Experimental/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Poscondicionamiento Isquémico/métodos , Dominios Homólogos a Pleckstrina , Daño por Reperfusión Miocárdica/metabolismo , Miocitos Cardíacos/metabolismo , Hipoxia/complicaciones , Glucosa
5.
Membranes (Basel) ; 12(12)2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36557082

RESUMEN

As an alternative route for aromatics and hydrogen production, methane dehydroaromatization (MDA) is of significant academic and industrial interest due to the abundance of natural gas resources and the intensive demand for aromatics and COx-free hydrogen. In the present work, a simulation study on MDA in membrane reactors (MRs) was performed with the aim of co-producing aromatics and COx-free hydrogen with a highly improved efficiency. The effects of various parameters, including catalytic activity, membrane flux and selectivity, as well as the operating conditions on the MR performance were discussed with respect to methane conversion, hydrogen yield, and hydrogen purity. The results show that catalytic activity and membrane flux and selectivity have significant impacts on CH4 conversion and H2 yield, whereas H2 purity is mainly dominated by membrane selectivity. A highly improved MDA is confirmed to be feasible at a relatively low temperature and a high feed pressure because of the hydrogen extraction effect. To further improve MDA in MRs by intensifying H2 extraction, a simple configuration combining a fixed-bed reactor (FBR) and an MR together is proposed for MDA, which demonstrates good potential for the high-efficiency co-production of aromatics and COx-free hydrogen.

6.
Langmuir ; 38(50): 15526-15533, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36475693

RESUMEN

Hydrate inhibitors are traditionally utilized to prevent hydrate plugging. In this study, the adhesion forces of cyclopentane (CP) hydrates with thermodynamic inhibitors (ethanol, urea, and NaCl) and anti-agglomerant inhibitors [sorbitan monooleate (Span 80) and lecithin] were measured to understand the effects of hydrate inhibitors on the adhesion forces of hydrates. It was found that the thermodynamic inhibitors increased the early hydrate interparticle adhesion force due to the enhanced liquid bridge force. However, the liquid bridge acted as a lubricant layer to prevent the irreversible agglomeration of hydrate after long-term contact. The hydrate adhesion forces decreased by 90.5-93.0% and 76.6-92.7% with an increase in the concentration of Span 80 and lecithin, respectively, from 0.1 to 1 wt %. Both rough morphology and low interfacial tension contributed to the adhesion force decrease of hydrate after the addition of anti-agglomerant inhibitors. The results may be helpful for understanding the mechanism of influence and quantifying the impact of hydrate inhibitors on hydrate interparticle adhesion force.

7.
J Biol Eng ; 16(1): 22, 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35996115

RESUMEN

Polylactic acid (PLA) is a versatile and biodegradable scaffold widely used in biomedical fields to repair tissue defects. Exosomes derived from mesenchymal stem cells (MSCs) are nano-sized extracellular vesicles, which play an important role in tissue engineering in recent years. The primary focus of this study was to develop a bioactive 3D PLA scaffold using exosome-based strategy to improve its osteogenic and immunoregulatory potential. We firstly successfully isolated MSC-derived exosomes (MSC-Exo). Morphological analysis revealed that MSC-Exo exhibits a typical cup-shaped morphology with high expression of exosomal marker CD63. MSC-Exo internalization into recipient cells were also investigated using flow cytometry and confocal laser scanning microscopy. Porous 3D PLA scaffold coated MSC-Exo were used for immunoregulatory and osteogenic testing. Exosomes released from 3D PLA scaffold were validated in RAW264.7 and hBMSCs. The cell proliferation and live/dead assay indicated high biocompatibility for PLA-Exo scaffold. Additionally, PLA-Exo scaffold could reduce the pro-inflammatory marker expression and reactive oxygen species (ROS) production, indicating potential immunoregulatory potential. It is also confirmed that PLA-Exo scaffold could potentiate osteogenic differentiation in the osteogenesis assay. In conclusion, our results demonstrate this bioactive 3D-printed PLA scaffolds with MSC-Exo modification holds immunoregulatory potential and favor osteogenic differentiation, thus having potential applications in bone tissue regeneration.

8.
Sci Rep ; 10(1): 8748, 2020 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-32457370

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

9.
Bioresour Technol ; 294: 122094, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31521980

RESUMEN

Pretreatment is a vital process for efficient saccharification and utilization of lignocellulose. In this study, crude glycerol derived from biodiesel production was used for pretreatment to facilitate selective saccharification via fast pyrolysis. Due to the efficient removal of alkali and alkaline earth metals (>95.0%) and lignin (79.4%) by crude glycerol pretreatment, the yield of levoglucosan was evaluated to 25.2% as compared to those from pure glycerol pretreated (14.4%) and untreated sugarcane bagasse (8.4%). Meanwhile, the production of inhibitors (e.g. acetic acid, phenol) to biocatalysts was also obviously inhibited from crude glycerol pretreated biomass. Consequently, this work provided a cost-effective and eco-friendly pretreatment mode, which could not only make full utilization of crude glycerol, but also improve the fermentability of lignocellulosic pyrolysate.


Asunto(s)
Saccharum , Celulosa , Glicerol , Hidrólisis , Pirólisis
10.
Bioresour Technol ; 261: 403-411, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29684870

RESUMEN

The study concerned the thermal oxidative degradation kinetics of agricultural residues, peanut shell (PS) and sunflower shell (SS). The thermal behaviors were evaluated via thermogravimetric analysis and the kinetic parameters were determined by using distributed activation energy model (DAEM) and global kinetic model (GKM). Results showed that thermal oxidative decomposition of two samples processed in three zones; the ignition, burnout, and comprehensive combustibility between two agricultural residues were of great difference; and the combustion performance could be improved by boosting heating rate. The activation energy ranges calculated by the DAEM for the thermal oxidative degradation of PS and SS were 88.94-145.30 kJ mol-1 and 94.86-169.18 kJ mol-1, respectively. The activation energy obtained by the GKM for the oxidative decomposition of hemicellulose and cellulose was obviously lower than that for the lignin oxidation at identical heating rate. To some degree, the determined kinetic parameters could acceptably simulate experimental data.


Asunto(s)
Agricultura , Eliminación de Residuos , Celulosa , Cinética , Lignina , Oxidación-Reducción , Termogravimetría
11.
RSC Adv ; 8(22): 11946-11956, 2018 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-35539396

RESUMEN

Hydrate plugs are one of the highest risks for gas and oil transportation in pipelines, especially in deep sea environments. In a newly built-up loop, pilot-scale experiments were carried out to study typical hydrate plug phenomena and to explore the specific reasons behind these. A tetrahydrofuran (THF) hydrate slurry was formed and investigated in this loop fluid at two liquid loadings (50 vol% and 100 vol%) with/without a typical anti-agglomerant, KL-1. Morphology and temperature variations revealed that THF hydrate slurry evolution had four stages: (a) flowable fluid; (b) particle formation; (c) agglomeration; and (d) plug. The effect of liquid loading (LL) and an anti-agglomerant (AA) on morphology and temperature in three cases were studied. The morphologies in each stage were compared for the three cases. Hydrate conversion was calculated according to the liquid and solid volume proportion in these morphologies. From these morphologies, heterogeneous hydrate deposition was found to be more likely to happen in 50 vol% than in the 100 vol% LL system. The hydrate plug was also found to be induced by hydrate deposition rather than the bed at the bottom of the pipeline. By dispersing hydrate particle agglomeration, AA compressed hydrate deposition and the plug.

12.
Bioresour Technol ; 243: 37-46, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28651137

RESUMEN

Thermal oxidative decomposition characteristics, kinetics, and thermodynamics of rape straw (RS), rapeseed meal (RM), camellia seed shell (CS), and camellia seed meal (CM) were evaluated via thermogravimetric analysis (TGA). TG-DTG-DSC curves demonstrated that the combustion of oil-plant residues proceeded in three stages, including dehydration, release and combustion of organic volatiles, and chars oxidation. As revealed by combustion characteristic parameters, the ignition, burnout, and comprehensive combustion performance of residues were quite distinct from each other, and were improved by increasing heating rate. The kinetic parameters were determined by Coats-Redfern approach. The results showed that the most possible combustion mechanisms were order reaction models. The existence of kinetic compensation effect was clearly observed. The thermodynamic parameters (ΔH, ΔG, ΔS) at peak temperatures were calculated through the activated complex theory. With the combustion proceeding, the variation trends of ΔH, ΔG, and ΔS for RS (RM) similar to those for CS (CM).


Asunto(s)
Extractos Vegetales , Termodinámica , Calefacción , Cinética , Temperatura
13.
Bioresour Technol ; 241: 340-348, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28577483

RESUMEN

The thermal conversion characteristics, kinetics, and thermodynamics of agricultural residues, rape straw (RS) and wheat bran (WB), were investigated under non-isothermal conditions. TGA experiments showed that the pyrolysis characteristics of RS were quite different from those of WB. As reflected by the comprehensive devolatilization index, when the heating rate increased from 10 to 30Kmin-1, the pyrolysis performance of RS and WB were improved 5.27 and 5.96 times, respectively. The kinetic triplets of the main pyrolysis process of agricultural residues were calculated by the Starink method and the integral master-plots method. Kinetic analysis results indicated that the most potential kinetic models for the pyrolysis of RS and WB were D2 and F2.7, respectively. The thermodynamic parameters (ΔH, ΔG, and ΔS) were determined by the activated complex theory. The positive ΔH, positive ΔG, and negative ΔS at characteristic temperatures validated that the pyrolysis of agricultural residues was endothermic and non-spontaneous.


Asunto(s)
Agricultura , Eliminación de Residuos , Cinética , Temperatura , Termodinámica , Termogravimetría
14.
Environ Sci Technol ; 50(23): 13024-13031, 2016 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-27934283

RESUMEN

In this study, mechanical force applied to squeeze poly(sodium acrylate-co-2-hydroxyethyl methacrylate) hydrogels that contained seawater in order to obtain fresh water. By incorporating ionic monomer sodium acrylate (SA) into hydrogels, the salt rejection was significantly enhanced from 27.62% to 64.57% (feed concentration 35.00g/L NaCl solution). As SA's concentration continuously increased, salt rejection declined due to the change in hydrogel's matrix structure. Therefore, water recovery raised as the current swelling degree increased. We also measured pore size distribution by applying mercury intrusion porosimetry on each hydrogel sample in the interest of finding out whether the sample SA5/HEMA15 owned multi pore structure, since the result could be good for the desalination performance. After 4 times reused, the hydrogel remained good desalination performance. Although compared to reverse osmosis (RO) and multistage flash distillation (MSF) & multiple effect distillation (MED) the salt rejection of this hydrogel (roughly 64%) seemed low, the hydrogels can be used for forward osmosis and reverse osmosis, as pretreatment of seawater to reduce the energy consumption for the downstream.


Asunto(s)
Hidrogeles , Purificación del Agua , Membranas Artificiales , Ósmosis , Agua de Mar/química , Cloruro de Sodio/química
15.
Sci Rep ; 6: 23220, 2016 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-26996773

RESUMEN

Pectin as a novel natural kinetic hydrate inhibitor, expected to be eco-friendly and sufficiently biodegradable, was studied in this paper. The novel crystal growth inhibition (CGI) and standard induction time methods were used to evaluate its effect as hydrate inhibitor. It could successfully inhibit methane hydrate formation at subcooling temperature up to 12.5 °C and dramatically slowed the hydrate crystal growth. The dosage of pectin decreased by 66% and effective time extended 10 times than typical kinetic inhibitor. Besides, its maximum growth rate was no more than 2.0%/h, which was far less than 5.5%/h of growth rate for PVCap at the same dosage. The most prominent feature was that it totally inhibited methane hydrate crystal rapid growth when hydrate crystalline occurred. Moreover, in terms of typical natural inhibitors, the inhibition activity of pectin increased 10.0-fold in induction time and 2.5-fold in subcooling temperature. The extraordinary inhibition activity is closely related to its hydrogen bonding interaction with water molecules and the hydrophilic structure. Finally, the biodegradability and economical efficiency of pectin were also taken into consideration. The results showed the biodegradability improved 75.0% and the cost reduced by more than 73.3% compared to typical commercial kinetic inhibitors.


Asunto(s)
Metano/química , Pectinas/química , Enlace de Hidrógeno , Cinética , Soluciones , Termodinámica , Agua/química
16.
Biosens Bioelectron ; 25(6): 1516-20, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19889528

RESUMEN

This study reports a new approach of improving performance of microbial fuel cells (MFCs) by using a polypyrrole/anthraquinone-2,6-disulphonic disodium salt (PPy/AQDS)-modified anode. The immobilization of AQDS on a carbon felt anode was accomplished by electropolymerization of pyrrole while using AQDS as the dopant. The dual-chamber MFC operated with this modified anode in the presence of Shewanella decolorationis S12 showed the maximum power density of 1303 mW m(-2), which was 13 times larger than that obtained from the MFC equipped with an unmodified anode. Evidence from cyclic voltammerty (CV) and scanning electron microscopy (SEM) results indicated that the increase in power generation was assigned to the increased surface area of anode, the enhanced electron-transfer efficiency from the bacteria to the anode via immobilized AQDS, and an increase in the number of bacteria attached to anode.


Asunto(s)
Antraquinonas/química , Fuentes de Energía Bioeléctrica/microbiología , Electrodos , Polímeros/química , Pirroles/química , Shewanella/fisiología , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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