Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sci Total Environ ; 790: 148220, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34380245

RESUMO

With changing numbers, compositions, emission standards and fuel quality of on-road vehicles, it is imperative to accordingly characterize and update vehicular emissions of carbonaceous aerosols for better understanding their health and climatic effects. In this study, a 7-day field campaign was conducted in 2019 in a busy urban tunnel (>30,000 vehicles day-1) in south China with filter-based aerosol samples collected every 2 h at both the inlet and the outlet for measuring carbonaceous aerosols and their light absorbing properties. Observed fleet average emission factor (EF) of total carbon (TC) was 13.4 ± 8.3 mg veh-1 km-1, and 17.4 ± 11.3 mg veh-1 km-1 if electric and LPG-driven vehicles were excluded; and fleet average EF of organic carbon (OC) and elemental carbon (EC) was 8.5 ± 6.6 and 4.9 ± 2.6 mg veh-1 km-1 (11.0 ± 8.8 and 6.3 ± 3.6 mg veh-1 km-1 if excluding electric and LPG vehicles), respectively. Regression analysis revealed an average TC-EF of 319.8 mg veh-1 km-1 for diesel vehicles and 2.1 mg veh-1 km-1 for gasoline vehicles, and although diesel vehicles only shared ~4% in the fleet compositions, they still dominate on-road vehicular carbonaceous aerosol emissions due to their over 150 times higher average TC-EF than gasoline vehicles. Filter-based light absorption measurement demonstrated that on average brown carbon (BrC) could account for 19.1% of the total carbonaceous light absorption at 405 nm, and the average mass absorption efficiency of EC at 635 nm and that of OC at 405 nm were 5.2 m2 g-1 C and 1.0 m2 g-1 C, respectively.


Assuntos
Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , China , Monitoramento Ambiental , Material Particulado/análise , Emissões de Veículos/análise
2.
Dent Mater J ; 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34408118

RESUMO

This study aimed to evaluate the effect of aging on the color stability and bond strengths of dual-cured resin cements containing amine or amine-free self-initiators. Three dual-cured and one light-cured resin cements were used. The covered (by lithium disilicate ceramic disks) and uncovered groups (n=10) were included. Color measurements were tested after 24 h, 10,000 and 20,000 thermal cycles (TCs). Micro-shear bond strengths (µSBS) were tested after 24 h, 10,000 and 20,000 TCs, and failure modes were analyzed (n=14). Two-way ANOVA and Tukey's test were implemented for color difference (ΔE*ab) and µSBS (α=0.05). The mean ΔE*ab difference was significant among groups (p<0.001). The lowest ΔE*ab values were obtained for dual-cured resin cement with amine-free self-initiators dual-cured cement after aging in all dual-cured resin cements, and the µSBS of the dual-cured resin cements on ceramic was significantly higher than that of the light-cured ones after aging (p<0.001).

3.
Comput Intell Neurosci ; 2021: 2837584, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34413884

RESUMO

In recent years, most of the communication places are using business English manual simultaneous interpretation or electronic equipment translation. In the context of diverse cultures, the way English is used and its grammar vary from country to country. In the face of this situation, how to optimize business English translation technology and improve the accuracy of business communication content is one of the research contents of scholars all over the world. This paper first introduces the purpose of business English translation and the gap between business English translation and general English translation. Secondly, a genetic algorithm is used to optimize the structure of the BP neural network, and the combination of the two improves the ability of translation search. This paper compares the influence of the traditional BP algorithm and the BP algorithm optimized by genetic algorithm on the construction of a business English translation model. The results show that BP neural network optimized by the genetic algorithm can improve the speed of business English text translation, reduce the impact of semantic errors on the accuracy of the translation model, and improve the efficiency of translation.


Assuntos
Algoritmos , Redes Neurais de Computação , Humanos , Traduções
4.
Environ Sci Technol ; 55(9): 5721-5730, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33797897

RESUMO

Despite the large reduction in anthropogenic activities due to the outbreak of COVID-19, air quality in China has witnessed little improvement and featured great regional disparities. Here, by combining observational data and simulations, this work aims to understand the diverse air quality response in two city clusters, Yangtze River Delta region (YRD) and Pearl River Delta region (PRD), China. Though there was a noticeable drop in primary pollutants in both the regions, differently, the maximum daily 8 h average ozone (O3) soared by 20.6-76.8% in YRD but decreased by 15.5-28.1% in PRD. In YRD, nitrogen oxide (NOx) reductions enhanced O3 accumulation and hence increased secondary aerosol formation. Such an increment in secondary organic and inorganic aerosols under stationary weather reached up to 36.4 and 10.2%, respectively, which was further intensified by regional transport. PRD was quite the opposite. The emission reductions benefited PRD air quality, while regional transport corresponded to an increase of 17.3 and 9.3% in secondary organic and inorganic aerosols, respectively. Apart from meteorology, the discrepancy in O3-VOCs-NOx relationships determined the different O3 responses, indicating that future emission control shall be regionally specific, instead of one-size-fits-all cut. Overall, the importance of regionally coordinated and balanced control strategy for multiple pollutants is highly emphasized.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Ozônio , Poluentes Atmosféricos/análise , China , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Ozônio/análise , SARS-CoV-2 , Estações do Ano
5.
Materials (Basel) ; 14(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804142

RESUMO

It is well known that the vertical tunnel field effect transistor (TFET) is easier to fabricate than the conventional lateral TFETs in technology. Meanwhile, a lightly doped pocket under the source region can improve the subthreshold performance of the vertical TFETs. This paper demonstrates a dual material gate heterogeneous dielectric vertical TFET (DMG-HD-VTFET) with a lightly doped source-pocket. The proposed structure adopts a GaSb/GaAs0.5Sb0.5 heterojunction at the source and pocket to improve the band-to-band tunneling (BTBT) rate; at the same time, the gate electrode is divided into two parts, namely a tunnel gate (M1) and control gate (M2) with work functions ΦM1 and ΦM2, where ΦM1 > ΦM2. In addition, further performance enhancement in the proposed device is realized by a heterogeneous dielectric corresponding to a dual material gate. Simulation results indicate that DMG-HD-VTFET and HD-VTFET possess superior metrics in terms of DC (Direct Current) and RF (Radio Frequency) performance as compared with conventional VTFET. As a result, the ON-state current of 2.92 × 10-4 A/µm, transconductance of 6.46 × 10-4 S/µm, and average subthreshold swing (SSave) of 18.1 mV/Dec at low drain voltage can be obtained. At the same time, DMG-HD-VTFET could achieve a maximum fT of 459 GHz at 0.72 V gate-to-source voltage (Vgs) and a maximum gain bandwidth (GBW) of 35 GHz at Vgs = 0.6 V, respectively. So, the proposed structure will have a great potential to boost the device performance of traditional vertical TFETs.

6.
Nanotechnology ; 32(30)2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33780919

RESUMO

The charge trapping effect plays a key role in multi-bit memory devices and brain-like neuron devices. Herein, MoS2field effect transistors are fabricated, incorporating Al into host La2O3as the gate dielectric, which exhibit excellent electrical properties with an on-off ratio in the memory window of ∼106and a memory window ratio of ∼40%. Furthermore, the charge trapping and de-trapping processes were systematically studied, and the time constants are obtained from time-domain characteristics. Making use of the charge trapping effect, the threshold voltage of the device can be continuously adjusted. The oxide layer trap density and the interface state trap density are extracted using the charge separation method. These theoretical studies provide a deeper understanding of ways to control the charge trapping process, benefitting the commercialization of two-dimensional electronic devices and the development of new charge trapping devices.

7.
Environ Pollut ; 280: 116972, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33774547

RESUMO

Vehicle emission is an important source of ammonia (NH3) in urban areas. To better address the role of vehicle emission in urban NH3 sources, the emission factor of NH3 (NH3-EF) from vehicles running on roads under real-world conditions (on-road vehicles) needs to update accordingly with the increasingly tightened vehicle emission standards. In this study, laser-absorption based measurements of NH3 were conducted during a six-day campaign in 2019 at a busy urban tunnel with a daily traffic flow of nearly 40,000 vehicles in south China's Pearl River Delta (PRD) region. The NH3-EF was measured to be 16.6 ± 6.3 mg km-1 for the on-road vehicle fleets and 19.0 ± 7.2 mg km-1 for non-electric vehicles, with an NH3 to CO2 ratio of 0.27 ± 0.09 ppbv ppmv-1. Multiple linear regression revealed that the average NH3-EFs for gasoline vehicles (GVs), liquefied petroleum gas vehicles, and heavy-duty diesel vehicles (HDVs) were 18.8, 15.6, and 44.2 mg km-1, respectively. While NH3 emissions from GVs were greatly reduced with enhanced performance of engines and catalytic devices to meet stricter emission standards, the application of urea selective catalytic reduction (SCR) in HDVs makes their NH3 emission an emerging concern. Based on results from this study, HDVs may contribute over 11% of the vehicular NH3 emissions, although they only share ∼4% by vehicle numbers in China. With the updated NH3-EFs, NH3 emission from on-road vehicles was estimated to be 9 Gg yr-1 in the PRD region in 2019, contributing only 5% of total NH3 emissions in the region, but still might be a dominant NH3 source in the urban centers with little agricultural activity.


Assuntos
Poluentes Atmosféricos , Amônia , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Lasers , Veículos Automotores , Emissões de Veículos/análise
8.
Micromachines (Basel) ; 11(12)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339124

RESUMO

The general preparation method of large-area, continuous, uniform, and controllable vdW heterostructure materials is provided in this paper. To obtain the preparation of MoS2/h-BN and WS2/h-BN heterostructures, MoS2 and WS2 material are directly grown on the insulating h-BN substrate by atmospheric pressure chemical vapor deposition (APCVD) method, which does not require any intermediate transfer steps. The test characterization of MoS2/h-BN and WS2/h-BN vdW heterostructure materials can be accomplished by optical microscope, AFM, Raman and PL spectroscopy. The Raman peak signal of h-BN material is stronger when the h-BN film is thicker. Compared to the spectrum of MoS2 or WS2 material on SiO2/Si substrate, the Raman and PL spectrum peak positions of MoS2/h-BN heterostructure are blue-shifted, which is due to the presence of local strain, charged impurities and the vdW heterostructure interaction. Additionally, the PL spectrum of WS2 material shows the strong emission peak at 1.96 eV, while the full width half maximum (FWHM) is only 56 meV. The sharp emission peak indicates that WS2/h-BN heterostructure material has the high crystallinity and clean interface. In addition, the peak position and shape of IPM mode characteristic peak are not obvious, which can be explained by the Van der Waals interaction of WS2/h-BN heterostructure. From the above experimental results, the preparation method of heterostructure material is efficient and scalable, which can provide the important support for the subsequent application of TMDs/h-BN heterostructure in nanoelectronics and optoelectronics.

9.
J Prosthet Dent ; 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33008629

RESUMO

STATEMENT OF PROBLEM: Lithium disilicate (LD) is a popular dental ceramic and has been a focus of dental research. Nevertheless, a quantified literature analysis focusing on the research of lithium disilicate is lacking. PURPOSE: The purpose of this bibliometric analysis was to review the progress of research into lithium disilicate in dentistry, including the identification of contributing researchers, organizations, countries or regions, journals, and the analysis of high-impact keywords and research trending. MATERIAL AND METHODS: The search was carried out within the topic field of the Web of Science (WoS) database, collecting publications related to LD from between 1996 and 2019. Metadata including the titles, abstracts, keywords, authors, affiliations, countries or regions, and references were extracted. Bibliometric indicators in terms of documents, authors, journals, and keywords were analyzed. RESULTS: Between 1996 and 2019, the dental research on LD trended upward. Scholars in the United States, Germany, Switzerland, and Brazil actively participated in the research on LD, and publications from the United States had the most citations. The Journal of Prosthetic Dentistry and Dental Materials were the major contributing journals. High-impact terms could be categorized into types of restorative material, types of prostheses, and properties or techniques of materials. Co-occurrence and relative normalized citation analysis of keywords highlighted several research interests, such as comparison studies between LD and zirconia, computer-aided design and computer-aided manufacturing (CAD-CAM) techniques, and the performance of complete coverage LD restorations. CONCLUSIONS: With the global upsurge in research on lithium disilicate, extensive collaborations and citations have been noted among authors, institutions, and countries or regions. Research hotspots include types of restorative material, types of prostheses, and properties or techniques of materials.

10.
J Colloid Interface Sci ; 565: 436-448, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31982710

RESUMO

A novel sandwich-like structure material was exploited for the fabrication of an effective corrosion resistance system. An environmentally friendly composite material was synthesized by installing 8-hydroxyquinoline (8-HQ) on the surface of graphene oxide (GO). In order to prevent leakage of corrosion inhibitor 8-HQ, GO/8-HQ was modified by polydopamine (PDA), denoted as GO/8-HQ/PDA. A sandwich-like structure (GO/8-HQ/PDA) enables long-term stable storage of corrosion inhibitor in the protective matrix. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were utilized to verify the sandwich-like structure of GO/8-HQ/PDA. The electrochemical tests in a 3.5 wt% NaCl solution showed that the addition of well-dispersed GO/8-HQ/PDA into epoxy system (GO/8-HQ/PDA-EP) remarkably improved corrosion protection of AZ31b magnesium alloy compared with pure epoxy (EP) coating. The sandwich structure protects the activity and structural integrity of the corrosion inhibitor (8-HQ). The corrosion inhibitor (8-HQ) of the GO/8-HQ/PDA sandwich structure cuts off the ion exchange between the metal alloy and the electrolyte solution, which hinders the electrochemical corrosion of the metal. A possible corrosion resistance mechanism of GO/8-HQ/PDA is fully discussed. This study provides feasibilities for the immobilization of corrosion inhibitors on the metal surface.

11.
Curr Med Sci ; 39(1): 37-43, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30868489

RESUMO

This study aimed to verify the effects of berberine (BBR) on the fat metabolism proteins involved in the sirtuin 3 (SIRT3)/adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) pathway in the liver tissues of rats with high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD). Forty-eight rats were randomly divided into the normal control (NC) group, HFD group or BBR group, with 16 rats in each group. After 8 and 16 weeks of treatment, serum and liver samples were collected. Subsequently, body parameters, biochemical parameters and liver pathology were examined. The expression levels of proteins involved in the SIRT3/AMPK/ACC pathway in the liver were detected by Western blotting. After 8 and 16 weeks of a HFD, the successful establishment of rat models with different degrees of NAFLD was confirmed by hematoxylin and eosin (H&E) and Oil Red O staining. NAFLD rat models exhibited obesity and hyperlipidemia, and the protein expression levels of SIRT3, p-AMPK, p-ACC, and CPT-1A in the liver were significantly decreased compared to those in the NC group. The concurrent administration of BBR with the HFD effectively improved serum and liver lipid profiles and ameliorated liver injury. Furthermore, the protein expression levels of SIRT3, p-AMPK, p-ACC, and CPT-1A in the liver were significantly increased in the BBR group as compared with those in the HFD group. In conclusion, our data suggest that the mechanism by which BBR ameliorates HFD-induced hepatic steatosis may be related to the activation of the SIRT3/AMPK/ACC pathway in the liver.


Assuntos
Berberina/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/induzido quimicamente , Transdução de Sinais/efeitos dos fármacos , Acetil-CoA Carboxilase/metabolismo , Adenilato Quinase/metabolismo , Animais , Berberina/farmacologia , Carnitina O-Palmitoiltransferase/metabolismo , Modelos Animais de Doenças , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Fosforilação/efeitos dos fármacos , Distribuição Aleatória , Ratos , Sirtuínas/metabolismo
12.
J Prosthet Dent ; 121(3): 549.e1-549.e7, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30782454

RESUMO

STATEMENT OF PROBLEM: Although newly developed photoinitiators can make up for the limitations of camphorquinone, their absorption spectra are different. However, little attention has been paid to the compatibility of available wavelength spectra of light-polymerization units (LPUs) and photoinitiators within resin cements. PURPOSE: The purpose of this in vitro study was to evaluate the effect of monowave and polywave light-emitting diode (LED) units on the adhesion of dual-polymerizing self-adhesive resin cements to monolithic zirconia. MATERIAL AND METHODS: Monowave LPUs and polywave LPUs were chosen to polymerize 2 dual-polymerizing self-adhesive resin cements. Ninety-six zirconia disks were randomly divided into 4 groups as different combinations of LPUs and resin cements, namely ES-U200, BS-U200, ES-SC, and BS-SC. Resin cements were adhered to zirconia disks, and the microshear bond strength (µSBS) test was conducted after 24 hours of H2O storage (24 h) and 10 000 thermocycles (10k/TC). Failure modes were examined by stereomicroscopy and scanning electron microscopy (SEM). The degree of conversion (DC) was tested both immediately and 24 hours later. In statistical analyses, 2-way ANOVA and the Tukey honestly significant difference post hoc test were performed for µSBS and DC results, and chi-square test was performed for failure mode analysis (α=.05 for all tests). RESULTS: The 2-way ANOVA demonstrated that different combinations of LPUs and resin cements, as well as different artificial aging levels, significantly influenced microshear bond strength values (P<.001). The interactions between 2 factors were also significant (P<.001). The BS-SC group possessed relatively high bond strength in both 24-hour and 10k/TC aging levels. For the same resin cement, no significant difference was found in the immediate DC (P=.405 for U200 and P=.708 for SC). At 24 hours, DC and BS-U200 values were significantly higher than ES-U200 values (P=.002), whereas BS-SC values were not significantly different from ES-SC values (P=.284). CONCLUSIONS: Within the limitation of this in vitro study, the emission spectra of LED units significantly influenced the bond strengths, DC, and failure mode of dual-polymerizing self-adhesive resin cements to zirconia at both immediate and artificial aging levels. The LPU should provide light energy to match the absorption wavelengths of photoinitiators in the resin cements.


Assuntos
Colagem Dentária , Cimentos de Resina , Teste de Materiais , Polimerização , Propriedades de Superfície , Zircônio
13.
Probiotics Antimicrob Proteins ; 11(1): 175-185, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29353414

RESUMO

The aim of this study was to investigate how the effects of compound probiotics modulate the gut microbiota, short-chain fatty acid (SCFA), body composition, serum and liver lipids, and inflammatory markers in non-alcoholic fatty liver disease (NAFLD) rats. Twenty-four male SD rats were randomly divided into 3 groups: normal control group (standard feed), high-fat diet (HFD) feeding group (83% standard feed + 10% lard oil + 1.5% cholesterol + 0.5% cholate + 5% sucrose), and compound probiotics intervention group (HFD + 0.6 g × kg-1 × d-1 compound probiotics). The microbial population was assessed by 16S rDNA amplification and sequence analysis. Body composition, serum and liver lipids, serum inflammatory markers, colonic SCFAs, and relative proteins were assessed. The results showed that compound probiotics significantly reduced body weight, visceral and total fat mass, and the levels of hepatic TC and TG and serum TG, FFA, ALT, LPS, IL-1ß, and IL-18 (P < 0.05). The proportions of TM7 phylum (0.06 vs 1.57%, P < 0.05) clearly increased, while that of Verrucomicrobia phylum (5.69 vs 2.61%, P < 0.05) clearly decreased. Compound probiotics also increased the representation of Ruminococcus genus (0.95 vs 1.83%, P < 0.05), while the proportion of Veillonella genus decreased (0.10 vs 0.03%, P < 0.05). The levels of colonic SCFAs and GPR43, NLRP3, ASC, and CASPASE-1 proteins also changed significantly (P < 0.05). Compound probiotics modulated gut microbiota, SCFAs, and their receptor GPR43 in NAFLD rats. These changes might inhibit lipid deposition and chronic metabolic inflammation in response to the insult of HFD.


Assuntos
Disbiose , Microbioma Gastrointestinal , Inflamação/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Probióticos/administração & dosagem , Receptores Acoplados a Proteínas G/fisiologia , Administração Oral , Animais , Composição Corporal , Doença Crônica , Citocinas/sangue , Dieta Hiperlipídica , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos Voláteis/biossíntese , Lipídeos/sangue , Masculino , Hepatopatia Gordurosa não Alcoólica/imunologia , Ratos , Ratos Sprague-Dawley
14.
ACS Appl Mater Interfaces ; 10(43): 37529-37534, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30229646

RESUMO

Development of metal-organic framework (MOF) films for selectively positioning inhibitors in metallic anticorrosion applications remains a substantial challenge due to the difficulty of controlling the arrangement of inhibitor molecules in MOF pores. Cetyltrimethyl ammonium bromide (CTAB), which contains hydrophobic and hydrophilic tails, was chosen as a prototypical inhibitor and was selectively located in the pores of the classic HKUST-1 thin film on a metallic surface. Experimental results reveal that the prepared CTAB@HKUST-1 film displays good metallic anticorrosion performances, especially for bronze conservation. A possible anticorrosion mechanism of CTAB@HKUST-1 is proposed and fully discussed. The study provides an avenue for developing MOF-based thin films for metallic anticorrosion applications to address the environmental development issues related to corrosion.

15.
Artigo em Inglês | MEDLINE | ID: mdl-30105078

RESUMO

We evaluate the effects of the Chaihu-Shugan-San decoction on intestinal microbe dysbiosis and chronic metabolic inflammation via the NLRP3 pathway in NAFLD rats that were fed a high-fat diet. Twenty-four SD rats (male, six weeks old, 200 ± 20 g) were randomly divided into three groups: normal control group (NC group), high-fat diet-fed group (HFD group), and Chaihu-Shugan-San decoction intervention group (CH group). The NC group rats were given standard feed, the HFD group rats were all fed a high-fat diet (83% standard feed + 10% lard oil + 5% sucrose + 1.5% cholesterol + 0.5% cholate), and the CH group rats were given a HFD plus Chaihu-Shugan-San at 9.6 g•kg-1•d-1. Body composition, serum and liver lipids, inflammatory markers, intestinal microbial population, and the NLRP3 pathway-associated protein were assessed. The results showed that Chaihu-Shugan-San decoction significantly reduced body weight and total fat mass and the levels of serum LPS, TG, TNF-α, IL-1ß, and IL-18, as well as liver TC, TG, TNF-α, IL-1ß, and IL-18 (P < 0.05). The abundance of Enterobacteriaceae (0.375% versus 0.064%, P < 0.05), Staphylococcaceae families (0.049% versus 0.016%, P < 0.05) and Veillonella genus (0.096% versus 0.009%, P < 0.01) significantly decreased, whereas the abundance of Anaeroplasma genus (0.0005% versus 0.0178%, P < 0.01) significantly increased. The expression levels of NLRP3, ASC, and Caspase-1 were changed significantly (P < 0.05). In summary, the Chaihu-Shugan-San decoction modulated intestinal microbe dysbiosis, reduced fat accumulation, and alleviated inflammatory factor expression, which are all processes related to the NLRP3 inflammasome pathway in NAFLD rats.

16.
Biomed Pharmacother ; 102: 1025-1036, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29710519

RESUMO

BACKGROUND: Worldwide, non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease closely associated with obesity, diabetes and other metabolic diseases. Shenling Baizhu powder (SLBZP), a formulation of a variety of natural medicinal plants, has hepatoprotective properties and clinical efficacy in treating non-infectious intestinal disease. SLBZP has improved NAFLD symptoms; however, its mechanism of action is unknown. METHODS: We established an NAFLD model in rats given a high-fat diet (HFD), administered different interventions and measured serum biochemical indices and inflammatory factors. Liver tissues were stained with hematoxylin and eosin (HE) and oil red O, and colon tissues were analyzed by immunohistochemistry. The expression profiles of liver TLR4 pathway related protein was confirmed by western blotting. Changes in intestinal microbiota composition were analyzed using a 16S rDNA sequencing technique. RESULTS: Of note, SLBZP effectively reduced body weight in HFD-fed rats (p < 0.05). Serum biochemical analysis indicated that SLBZP decreased the serum level of total cholesterol (TC) and improved liver function. Additionally, SLBZP decreased the serum level of endotoxin, tumor necrosis factor α (TNF-α), interleukin-1ß (IL-ß) (p < 0.05), and decreased the expression of TLR4 pathway related protein. Pathological examination showed that SLBZP alleviates hepatic steatosis and repairs colon mucosa. Microbiome analysis revealed that SLBZP improved the abundance of intestinal microbiota. In taxonomy-based analysis, compared with control rats, SLBZP-treated rats showed obvious changes in intestinal microbiota composition. Moreover, SLBZP increased the relative abundance of short-chain fatty acid (SCFA)-producing bacteria, including Bifidobacterium and Anaerostipes. CONCLUSION: Taken together, these results suggest that the effects of SLBZP against NAFLD may be related to the increased abundance of beneficial gut microbiota and decreased levels of LPS in the portal vein.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/microbiologia , Animais , Biodiversidade , Peso Corporal/efeitos dos fármacos , Colo/efeitos dos fármacos , Colo/patologia , Dieta Hiperlipídica , Medicamentos de Ervas Chinesas/farmacologia , Inflamação/sangue , Inflamação/patologia , Lipídeos/sangue , Lipopolissacarídeos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/tratamento farmacológico , Obesidade/prevenção & controle , Tamanho do Órgão/efeitos dos fármacos , Filogenia , Pós , Ratos Sprague-Dawley , Transdução de Sinais
17.
Artigo em Inglês | MEDLINE | ID: mdl-29675053

RESUMO

The present study investigates the potential therapeutic mechanism underlying the effects of the Chinese herbal formula Hongqijiangzhi Fang (HJF) on nonalcoholic fatty liver disease (NAFLD) in rats. Male Sprague Dawley (SD) rats were randomly divided into 4 groups (n = 8): control group was fed a normal diet, three other groups were fed high-fat diets (HFD), and the two treatment groups were intragastrically given a compound probiotic or HJF during the molding time. After 16 w, related indices were detected. The results showed that HJF significantly reduced abdominal aorta serum cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), IL-1ß, and IL-18, portal venous serum lipopolysaccharide (LPS), and liver TC and TG levels in HFD-fed rats. HJF ameliorated hepatic steatosis in the liver and improved the intestinal barrier in HFD-fed rats. Activation of the NLRP3 inflammasome was reduced by HJF in HFD-fed rats. Additionally, the abundances of A. muciniphila (Verrucomicrobiaceae), F. rappini (Helicobacteraceae), and Enterobacteriaceae bacteria significantly decreased in HJF-treated HFD-fed rats. In conclusion, these result suggested that the Chinese herbal formula HJF reduced hepatic steatosis maybe through decreasing certain gut bacteria (such as Enterobacteriaceae bacteria and F. rappini), alleviating intestinal endotoxemia and reducing NLRP3 inflammasome activation.

18.
Int J Clin Exp Pathol ; 8(9): 11704-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617914

RESUMO

Ectopic liver (EL) tissue is a rare entity which is reported to occur in several organs such as the gallbladder, pancreas and some other places. The EL tissue is usually detected incidentally during laparoscopy or autopsy, and several potential mechanisms may explain the development of liver ectopia. Although ectopic liver tissue is usually asymptomatic, it develops the same pathologic conditions as orthotopic liver. Although incidental ectopic livers rarely existing and do not have clinical importance, they should be looked for during electron microscope scan and histopathological examination should be carried out to rule out pathological changes since development of hepatocellular carcinoma is a possible issue. In this article, we presented an EL tissue in stomach of which only two cases were reported previously and this is the first reported case of a laparoscopically treated EL which lies to the bottom submucosal of the stomach. It would seem sensible to resect the ectopic tissue under endoscopic and the patient was well when seen for follow-up three months later.


Assuntos
Coristoma/patologia , Fígado , Gastropatias/patologia , Adulto , Feminino , Humanos
19.
Ann Diagn Pathol ; 19(1): 33-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25622532

RESUMO

To investigate the significance between the expression of P27, Fragile Histidine Triad (FHIT), phosphatase and tensin homolog deleted on chromosome ten (PTEN), and P73 in esophageal squamous cell carcinoma (ESCC), paraffin-embedded tissue blocks of 200 cases were obtained from the Fourth Hospital of Hebei Medical University. The sections were used for (HE) and immunohistochemical staining streptavidin-perosidase (SP). The immunologic reagents used included antibodies against P27, FHIT, PTEN, and P73. From I- to II- and III-graded ESCC, the positive expression of P27 was decreased, but the P73 was increased, showing a ladded change (P < .05). The oncogene and tumor suppressor gene protein expression were related to the differentiation and can be one of the factors of influencing prognosis. The oncogene and tumor suppressor gene protein expression was related to the prognostic factor, and thus, it is valuable for clinical treatment and judging prognosis to detect the expression of P27, FHIT, PTEN, and P73 in ESCC.


Assuntos
Hidrolases Anidrido Ácido/biossíntese , Carcinoma de Células Escamosas/metabolismo , Proteínas de Ligação a DNA/biossíntese , Neoplasias Esofágicas/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas Nucleares/biossíntese , PTEN Fosfo-Hidrolase/biossíntese , Antígeno Nuclear de Célula em Proliferação/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Hidrolases Anidrido Ácido/genética , Adulto , Idoso , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Proteínas de Ligação a DNA/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , PTEN Fosfo-Hidrolase/genética , Inclusão em Parafina , Prognóstico , Antígeno Nuclear de Célula em Proliferação/genética , Fixação de Tecidos , Proteína Tumoral p73 , Proteínas Supressoras de Tumor/genética
20.
Artigo em Chinês | MEDLINE | ID: mdl-23662395

RESUMO

OBJECTIVE: To explore the possible mechanism of lipid deposition induced by interferon-gamma (IFN-gamma). METHODS: The mouse mesangial cells (MMC) were randomly divided into control group, stimulation group, stimulation + control vector group (sh-HMGB1) and stimulation+ specific sh-vector group (sh-SREBP-1). RT-PCR was used to detect the expression of HMGB1, SREBP-1 and fatty acid synthetase (FAS) mRNA; the protein expression was determined by Western blot. RESULTS: The Oil Red O staining revealed that the mouse mesangial cells showed significant lipid droplet in IFN-gamma group. IFN-gamma up-regulated the expression of HMGB1, SREBP-1, FAS mRNA and protein time-dependently; Transfection of MMC with HMGB1 siRNA resulted in the suppression of SREBP-1, FAS protein levels induced by IFN-gamma, following with decrease of lipid deposition. Stimulation with HMGB1 markedly induced expression of SREBP-1, FAS expression and peaked at 8 h, decreased at 12 h compared with that at 8 h. Sh-SREBP-1 decreased the lipid deposition induced by HMGB1 in MMC. CONCLUSION: IFN-gamma might induce lipid deposition in mouse mesangial cells partly by up-regulating the expression of HMGB1/SREBP-1/FAS.


Assuntos
Proteína HMGB1/metabolismo , Interferon gama/farmacologia , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Células Cultivadas , Ácido Graxo Sintases/metabolismo , Túbulos Renais/citologia , Metabolismo dos Lipídeos , Masculino , Camundongos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...