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1.
Tohoku J Exp Med ; 261(4): 257-265, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-37344419

RESUMO

Improving hepatic glucose and lipid metabolisms is an important strategy to treat type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease (T2DM-NAFLD). Silybin (SLB) has the potential hepatoprotection, while its oral bioavailability is poor. This study aims to investigate the functional role and mechanism of liposomal SLB in modulating glucose/lipid metabolism in T2DM-NAFLD. SLB was prepared by thin film dispersion method and characterized using dynamic light scattering, scanning electron microscope, high performance liquid chromatography and zeta potential analyzer. A rat model of T2DM-NAFLD was used to determine the role of liposomal SLB in regulating glycolipid metabolism and hepatic damage. Rat primary hepatocytes were used to demonstrate the hepatoprotection mechanism of liposomal SLB. The encapsulation efficiency was more than 80%, which showed the average particle size of 119.76 nm. Also, the average Zeta potential was -4.76 mV. These liposomes were spherical. In rats with T2DM-NAFLD, liposomal SLB alleviated insulin resistance and lipid metabolism, thereby improving hepatic lipid accumulation, inflammation and fibrosis. Besides, liposomal SLB elevated AMPK phosphorylation, and decreased collagen I/III, α-smooth muscle actin (α-SMA), transforming growth factor-ß1 (TGF-ß1) and the phosphorylation of Smad2/3. In hepatocyte model, compound C partially reversed the effects of liposomal SLB on cell viability, glycolipid metabolism and AMPK/TGF-ß1/Smad pathway activation. Liposomal SLB ameliorates hepatic glucose and lipid metabolisms in T2DM-NAFLD via activating AMPK/TGF-ß1/Smad pathway, providing an efficient strategy for treating T2DM-NAFLD.


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Fator de Crescimento Transformador beta1/metabolismo , Metabolismo dos Lipídeos , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/farmacologia , Silibina/farmacologia , Silibina/uso terapêutico , Silibina/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucose/metabolismo , Lipossomos/metabolismo , Lipossomos/farmacologia , Modelos Animais de Doenças , Fígado/metabolismo , Lipídeos/farmacologia , Glicolipídeos/metabolismo , Glicolipídeos/farmacologia
2.
J Am Chem Soc ; 143(51): 21648-21656, 2021 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-34913337

RESUMO

Exploring the three-dimensional (3D) drug distribution within a single cell at nanoscale resolution with mass spectrometry imaging (MSI) techniques is crucial in cellular biology, yet it remains a great challenge due to limited lateral resolution, detection sensitivities, and reconstruction problems. Herein, a microlensed fiber laser desorption post-ionization time-of-flight mass spectrometer (MLF-LDPI-TOFMS) was developed for the 3D imaging of two anticancer drugs within single cells at a 500 × 500 × 500 nm3 voxel resolution. Nanoscale desorption was obtained with a microlensed fiber (MLF), and a 157 nm post-ionization laser was introduced to enhance the ionization yield. Furthermore, a new type of alignment method for 3D reconstruction was developed on the basis of our embedded uniform circular polystyrene microspheres (PMs). Our findings demonstrate that this 3D imaging technique has the potential to provide information about the 3D distributions of specific molecules at the nanoscale level.


Assuntos
Imageamento Tridimensional/métodos , Nanotecnologia , Análise de Célula Única/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Antineoplásicos/química , Células HeLa , Humanos , Azul de Metileno/química , Microesferas , Poliestirenos , Proflavina/química
3.
Ecotoxicol Environ Saf ; 190: 110151, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923754

RESUMO

Potentially toxic metals (PTMs), associated with different size particles in soil, may play an important role in adverse health effect and risk for human. The objective is to evaluate the lung and gastrointestinal bioaccessibility and risk of PTMs in Pb-contaminated alkaline urban soil depending on the particle size fractions. The size fractions of 50-250 µm, 5-50 µm, 1-5 µm, <1 µm in Pb-contaminated alkaline urban soil from Baoji Heavy Industrial Base City, NW China, were screened by Sequential Wet Sieving Separation Procedure (SWSSP) based on Stokes' Law. The concentrations of 9 potentially toxic metals (As, Ba, Co, Cr, Cu, Mn, Ni, Pb and Zn) in each particle size fractions were characterized by ICP-OES and ICP-MS, and the in vitro bioaccessibility dependent of size fractions were evaluated by the simulation fluids of Artificial Lysosomal Fluid (ALF) and Gamble for lung, PBET, SBET, IVG, SBRC, UBM for gastric and intestinal, respectively. Health risks were assessed considering simulated external exposure using intestinal and lung bioaccessibility. The lung and gastrointestinal bioaccessibility and exposure risks of PTMs in fine particle size (i.e. <1 µm) was higher than larger particle size fractions (i.e. 50-250 µm, 5-50 µm, 1-5 µm), however, some different variations of bioaccessibility observed the simulation fluids and time dependent. In case of single PTMs, the lung bioaccessibilities of PTMs in ALF were higher than those in Gamble fluids, most prominent in Co, Cu, Mn and Zn, while the gastrointestinal [G + I] bioaccessibility of PTMs was less than those in gastric [G], like Cu, Mn, Pb and Zn mostly. The non-carcinogenic risks of these PTMs to children via inhalation were acceptable and higher than those of adults, but reverse for carcinogenic risk. Comparatively, the non-carcinogenic and carcinogenic risks of PTMs via ingestion pathway were both higher than those for adults. Although the risks from ingestion were in acceptable range, the total carcinogenic risks for children were more than 10-4, which would bring carcinogenic risks and should be paid attention to. It was noted that the toxic metal, Co in all size fractions was the most important contributor for noncarcinogenic risks and Cr mostly for carcinogenic risks via inhalation pathway for adults and children in local areas. However, Pb was the most important contributor for noncarcinogenic risk both for adults and children via ingestion pathway relative to Co and Cr for carcinogenic risks through hand-to-mouth ingestion. Those observations demonstrated the important role that the smaller particle fractionations in Pb-contaminated alkaline soil played in both bioaccessibility and the refinement of human health-risk assessments for the inhalation and ingestion pathway.


Assuntos
Arsênio/metabolismo , Trato Gastrointestinal/metabolismo , Pulmão/metabolismo , Metais Pesados/metabolismo , Tamanho da Partícula , Poluentes do Solo/metabolismo , Adulto , Arsênio/química , Disponibilidade Biológica , Criança , China , Cidades , Humanos , Metais Pesados/química , Modelos Biológicos , Medição de Risco/métodos , Poluentes do Solo/química
4.
J Nanobiotechnology ; 17(1): 54, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992018

RESUMO

BACKGROUND: Nanomaterials that exhibit intrinsic enzyme-like characteristics have shown great promise as potential antibacterial agents. However, many of them exhibit inefficient antibacterial activity and biosafety problems that limit their usefulness. The development of new nanomaterials with good biocompatibility and rapid bactericidal effects is therefore highly desirable. Here, we show a new type of terbium oxide nanoparticles (Tb4O7 NPs) with intrinsic oxidase-like activity for in vitro and in vivo antibacterial application. RESULTS: We find that Tb4O7 NPs can quickly oxidize a series of organic substrates in the absence of hydrogen peroxide. The oxidase-like capacity of Tb4O7 NPs allows these NPs to consume antioxidant biomolecules and generate reactive oxygen species to disable bacteria in vitro. Moreover, the in vivo experiments showed that Tb4O7 NPs are efficacious in wound-healing and are protective of normal tissues. CONCLUSIONS: Our results reveal that Tb4O7 NPs have intrinsic oxidase-like activity and show effective antibacterial ability both in vitro and in vivo. These findings demonstrate that Tb4O7 NPs are effective antibacterial agents and may have a potential application in wound healing.


Assuntos
Antibacterianos/química , Escherichia coli , Nanopartículas Metálicas/química , Óxidos/química , Oxirredutases/química , Staphylococcus aureus , Térbio/química , Cicatrização , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Sobrevivência Celular , Escherichia coli/efeitos dos fármacos , Hemólise , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos Endogâmicos BALB C , Óxidos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Térbio/farmacologia
5.
J Sep Sci ; 39(4): 762-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26632107

RESUMO

A novel triethylenetetramine-functionalized magnetic graphene oxide composite was prepared and used as a magnetic solid-phase extraction adsorbent for the fast detection of ten trace-level phenolic environmental estrogens in environmental water. The synthesized material was carefully characterized by scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and X-ray photoelectron spectroscopy to confirm the structure and components. The adsorption and desorption conditions of the adsorbent toward phenolic environmental estrogens were optimized in detailed to obtain the best extraction recovery and elution efficiency. Under the optimum conditions, the limits of detection of the method for ten phenolic environmental estrogens were in range of 0.15-1.5 ng/L, which was lower than the reported methods for phenolic environmental estrogens detection in literatures. This could be contributed to the unique structure and property of the as-prepared material. The developed method was successfully applied for the determination of environmental water samples with recoveries ranging from 88.5 to 105.6%.


Assuntos
Estrogênios/química , Grafite/química , Magnetismo , Óxidos/química , Fenol/química , Trientina/química , Água/química , Adsorção , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/métodos , Poluentes Ambientais , Limite de Detecção , Impressão Molecular , Polímeros/química , Reprodutibilidade dos Testes , Solventes/química , Poluentes Químicos da Água/química
6.
J Plant Physiol ; 258-259: 153389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33652172

RESUMO

Starch is a natural storage carbohydrate in plants and algae. It consists of two relatively simple homo-biopolymers, amylopectin and amylose, with only α-1,4 and α-1,6 linked glucosyl units. Starch is an essential source of nutrition and animal food, as well as an important raw material for industry. However, despite increasing knowledge, detailed information about its structure and turnover are largely lacking. In the last decades, most data were generated using bulk experiments, a method which obviously presents limitations regarding a deeper understanding of the starch metabolism. Here, we discuss some unavoidable questions arising from the existing data. We focus on a few examples related to starch biosynthesis, degradation, and structure - where these limitations strongly emerge. Closing these knowledge gaps will also be extremely important for taking the necessary steps in order to set up starch-providing crops for the challenges of the ongoing climate changes, as well as for increasing the usability of starches for industrial applications by biotechnology.


Assuntos
Amilopectina/metabolismo , Amilose/metabolismo , Produtos Agrícolas/metabolismo , Amilopectina/biossíntese , Amilose/biossíntese , Biopolímeros/metabolismo , Biotecnologia
7.
Vaccines (Basel) ; 9(6)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200441

RESUMO

At present, there are no vaccines available for hand, foot, and mouth disease, which is caused by Coxsackie virus A16 (CVA16) infection. In the present study, we isolated epidemic strains of CVA16 and optimized the production of the virus in Vero cells. The system comprised growing the infected cells on polymer fiber paper carriers in a serum-free medium containing 0.5% (w/v) lactalbumin hydrolysate a mini bioreactor. Disposable Bioflo310 and AmProtein Current perfusion bioreactors were used to monitor virus infection and Vero cell culture. The total number of cells increased from 1.5 × 109 to 3.0 × 1010. In our optimized culture process, the virus titer reached 7.8 × 107 TCID50/mL at three days after infection. The inactivated CVA16 prepared from our optimized culture procedure elicited a slightly higher neutralizing antibody titer compared with that derived from routine culture procedures. These results will promote the large-scale production of inactivated CVA16 vaccines using nonwoven polymer fiber paper cell cultures.

8.
Int J Biol Macromol ; 141: 876-884, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31476399

RESUMO

The physical mechanics and structural properties of composite films based on chitosan and syringic acid (SA) were studied in this study. The results indicated that the addition of SA made the chitosan-SA films exhibited higher density, water solubility and opacity, but the water vapor permeability and water content were decreased. In addition, Chitosan-SA films had a significant antibacterial effect on test bacteria. The surface and cross-section of chitosan-SA films were more uniform and smoother when combined with 0.25% and 0.5% 0f SA. The FT-IR and XRD spectra of the chitosan-SA film indicated that the interaction between chitosan and SA may be non-covalent, and DSC indicated that the thermal stability of the composite film was reduced. In summary, the modified color, increased bacteriostatic and water-blocking properties, as well as the slight changes in mechanical properties indicated that the addition of SA may contribute to extend the shelf life of the food. Thus, chitosan-SA films incorporating 0.25% and 0.5% of SA can be further explored as active packing materials for food preservation. The composite film was used for the preservation of quail egg coatings, and it was found that 0.25% and 0.5% of the coating film had a good preservation effect.


Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Quitosana/química , Ácido Gálico/análogos & derivados , Animais , Antibacterianos/farmacologia , Fenômenos Químicos , Embalagem de Alimentos , Conservação de Alimentos , Ácido Gálico/química , Fenômenos Mecânicos , Codorniz , Análise Espectral
9.
Asia Pac J Clin Nutr ; 24(2): 199-205, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26078235

RESUMO

Mantou, a traditional Chinese food, is widely consumed in the North China due to its nutritional value and good mouth-feel. However, its current family-style production is impeded due to short shelf-life caused by mold and starch retrogradation. The current packaging and storage methods are not efficient enough for mantou preservation. Recently, a novel, hot online package technology has attracted attention due to its high processing efficiency and low cost. Most importantly, by using this methodology, secondary contamination by microbes can be avoided and starch retrogradation can be markedly delayed, with mantou shelf-life under room temperature extended from a few to at least 90 days without any additives. In this review, the mechanisms of mantou quality deterioration are explained and the advantages of hot package technology addressed and compared with other packaging methods, such as frozen chain storage. In this way, not only wheat, but also other grains (including whole-grains) and ingredients may be mantou constituents, to enhance nutrition of traditional mantou. There is now a technological opportunity for mantou to become a more nutritious, sustainable and affordable foodstuff in local communities.


Assuntos
Pão/microbiologia , Pão/normas , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Valor Nutritivo , Pão/análise , China , Grão Comestível , Manipulação de Alimentos/métodos , Embalagem de Alimentos/tendências , Qualidade dos Alimentos , Humanos , Amido/química , Vapor , Triticum
10.
J Chromatogr A ; 1422: 1-12, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26477521

RESUMO

Microcystins (MCs), a group of cyclic heptapeptide heaptoxins and tumor promoters, are generated by cyanobacteria occurring in surface waters, such as eutrophic lakes, rivers, and reservoirs. In this present study, a novel double-sided magnetic molecularly imprinted polymer modified graphene oxide (DS-MMIP@GO) based magnetic solid-phase extraction (MSPE) method was developed for fast, effective and selective enrichment, and recognition of trace MCs in environmental water samples combined with high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The synthesized novel DS-MMIP@GO was used as the adsorbents in this work and was carefully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and Raman spectra. The adsorption and desorption conditions of DS-MMIP@GO toward MCs were optimized in detail to obtain the highest binding capacity, selectivity, and release efficiency. Under the optimum conditions, the enrichment factors of the method for eight target MCs were found to be 2000. The limits of quantitation (LOQs) of the method for eight MCs were in range of 0.1-2.0ngL(-1). The double-sided MMIP modified structure provided DS-MMIP@GO with abundant adsorption sites and permitted it to exhibit excellent enrichment and selectivity toward trace-level MCs. The proposed method was successfully applied for the analysis of environmental water samples with recoveries ranging from 84.1 to 98.2%. Compared to conventional methods for MCs detection reported in literatures, the one developed in this work based on DS-MMIP@GO and LC-MS/MS showed much faster, more sensitive, and more convenient.


Assuntos
Cromatografia Líquida , Monitoramento Ambiental/métodos , Água Doce/química , Microcistinas/análise , Microcistinas/isolamento & purificação , Óxidos/química , Espectrometria de Massas em Tandem , Grafite/química , Magnetismo , Microscopia Eletrônica de Transmissão , Polímeros/química , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
11.
J Cent South Univ ; 19(3): 645-650, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-32288947

RESUMO

Existed evidences show that airborne transmission of human respiratory droplets may be related with the spread of some infectious disease, such as severe acute respiratory syndrome (SARS) and H1N1 pandemic. Non-pharmaceutical approaches, including ventilation system and personal protection, are believed to have certain positive effects on the reduction of co-occupant's inhalation. This work then aims to numerically study the performances of mouth covering on co-occupant's exposure under mixing ventilation (MV), under-floor air distribution (UFAD) and displacement ventilation (DV) system, using drift-flux model. Desk partition, as one generally employed arrangement in plan office, is also investigated under MV. The dispersion of 1, 5 and 10 µm droplet residuals are numerically calculated and CO2 is used to represent tracer gas. The results show that using mouth covering by the infected person can reduce the co-occupant's inhalation greatly by interrupting direct spread of the expelled droplets, and best performance can be achieved under DV since the coughed air is mainly confined in the microenvironment of the infected person. The researches under MV show that the two interventions, mouth covering and desk partition, achieve almost the same inhalation for fine droplets while the inhalation of the co-occupant is lower when using mouth covering for large droplets.

12.
Shanghai Kou Qiang Yi Xue ; 18(5): 472-4, 2009 Oct.
Artigo em Zh | MEDLINE | ID: mdl-19907850

RESUMO

PURPOSE: To evaluate the clinical effects between gold-alloy post-core-crowns and nickel-chromium-alloy post-core-crowns. METHODS: Four hundred incisors, canines and premolars from 289 patients were selected. The crown had been destroyed seriously and root canal therapy was carried out. The root canal and the surface of the root were prepared well, then silicone impression material was injected into the root canal and the prepared plastic pin was inserted. Precise impression was taken and divided into two groups randomly. Group A was restored by gold-alloy post-core-crowns, while Group B was restored by nickel-chromium-alloy post-core-crowns. The patients were followed up for 3 years, the clinical effects were evaluated and compared using SPSS10.0 software package for Chi-square test. RESULTS: There was no significant difference(P>0.05) of maintenance rate between the two groups, but there was significant difference (P<0.05) in the occurence of inflammation and staining of gingiva. CONCLUSION: Gold-alloy post-core-crown is more suitable for restoration of teeth defects than nickel-chromium-alloy post-core-crown. Supported by Research Fund of Medical Science and Technology of Guangdong Province (Grant No. WSTJJ20070101310103196603041632).


Assuntos
Coroas , Ouro , Níquel , Técnica para Retentor Intrarradicular , Ligas , Dente Pré-Molar , Cromo , Ligas de Cromo , Humanos , Incisivo , Tratamento do Canal Radicular , Coroa do Dente
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