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2.
Nicotine Tob Res ; 26(4): 474-483, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-37535700

RESUMO

INTRODUCTION: Electronic cigarettes (E-cigs) are in a controversial state. Although E-cig aerosol generally contains fewer harmful substances than smoke from burned traditional cigarettes, aerosol along with other compounds of the E-cigs may also affect lung functions and promote the development of lung-related diseases. We investigated the effects of E-cig on the pulmonary functions of male C57BL/6 mice and reveal the potential underlying mechanisms. METHODS: A total of 60 male C57BL/6 mice were randomly divided into four groups. They were exposed to fresh-air, traditional cigarette smoke, E-cig vapor with 12 mg/mL of nicotine, and E-cig with no nicotine for 8 weeks. Lung functions were evaluated by using quantitative analysis of the whole body plethysmograph, FlexiVent system, lung tissue histological and morphometric analysis, and RT-PCR analysis of mRNA expression of inflammation-related genes. In addition, the effects of nicotine and acrolein on the survival rate and DNA damage were investigated using cultured human alveolar basal epithelial cells. RESULTS: Exposure to E-cig vapor led to significant changes in lung functions and structures including the rupture of the alveolar cavity and enlarged alveolar space. The pathological changes were also accompanied by increased expression of interleukin-6 and tumor necrosis factor-α. CONCLUSIONS: The findings of the present study indicate that the safety of E-cig should be further evaluated. IMPLICATIONS: Some people currently believe that using nicotine-free E-cigs is a safe way to smoke. However, our research shows that E-cigs can cause lung damage regardless of whether they contain nicotine.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Camundongos , Animais , Masculino , Humanos , Nicotina/efeitos adversos , Nicotina/metabolismo , Camundongos Endogâmicos C57BL , Pulmão , Aerossóis/farmacologia
3.
Polymers (Basel) ; 11(6)2019 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-31159509

RESUMO

Flexible conductive materials have greatly promoted the rapid development of intelligent and wearable textiles. This article reports the design of flexible polypyrrole/bacterial cellulose (PPy/BC) conductive nanocomposites by in situ chemical polymerization. Box-Behnken response surface methodology has been applied to optimize the process. The effects of the pyrrole amount, the molar ratio of HCl to pyrrole and polymerization time on conductivity were investigated. A flexible PPy/BC nanocomposite was obtained with an outstanding electrical conductivity as high as 7.34 S cm-1. Morphological, thermal stability and electrochemical properties of the nanocomposite were also studied. The flexible PPy/BC composite with a core-sheath structure exhibited higher thermal stability than pure cellulose, possessed a high areal capacitance of 1001.26 mF cm-2 at the discharge current density of 1 mA cm-2, but its cycling stability could be further improved. The findings of this research demonstrate that the response surface methodology is one of the most effective approaches for optimizing the conditions of synthesis. It also indicates that the PPy/BC composite is a promising material for applications in intelligent and wearable textiles.

4.
Nanoscale ; 11(4): 2008-2016, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30644929

RESUMO

Bone morphogenetic protein (BMP)-9 has been associated with insulin resistance and type 2 diabetes mellitus. However, methods for delivering exogenous BMP-9 genes in vivo are lacking. In this study, we developed a gene delivery system using polyethyleneimine (PEI)-based core-shell nanoparticles (PCNs) as gene delivery carriers, and investigated the effectiveness and safety for delivery of the shBMP-9 gene. PCNs possessed a well-defined core-shell nanostructure with hydrophobic polymer cores and dense PEI shells of uniform particle size and highly positively charged surfaces. In vitro evaluation suggested that PCNs had high loading capacity for exogenous genes and low cytotoxicity toward hepatocytes. The transfection efficiency of PCNs/pENTR-shBMP9 complexes was higher than that of commercial lipofectamine 2000/shBMP9. In vivo studies showed that PCNs/pENTR-shBMP9 transfection led to a significant decrease in hepatic BMP9 expression compared with pENTR-shBMP9 transfection. Under high fat diet (HFD) feeding, PCNs/pENTR-shBMP9 mice exhibited aggravated glucose and insulin tolerance. At a molecular level, PCNs/pENTR-shBMP9 mice displayed elevated PEPCK protein levels and lower levels of InsR and Akt phosphorylation than pENTR-shBMP9 mice. These results suggest that the biological effects of PCNs/pENTR-shBMP9 in vivo are much more effective than those of pENTR-shBMP9. Therefore, the polyethyleneimine (PEI)-based core-shell nanoparticle can be applied as promising nanocarriers for effective and safe gene delivery.


Assuntos
Portadores de Fármacos/química , Fator 2 de Diferenciação de Crescimento/metabolismo , Nanopartículas/química , Polietilenoimina/química , RNA Interferente Pequeno/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/terapia , Dieta Hiperlipídica , Modelos Animais de Doenças , Fator 2 de Diferenciação de Crescimento/antagonistas & inibidores , Fator 2 de Diferenciação de Crescimento/genética , Células Hep G2 , Humanos , Insulina/metabolismo , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/toxicidade , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/uso terapêutico , Transfecção
5.
Polymers (Basel) ; 10(12)2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30961251

RESUMO

At present, the pollution of microplastic directly threatens ecology, food safety and even human health. Polyethylene terephthalate (PET) is one of the most common of microplastics. In this study, the micro-size PET particles were employed as analog of microplastic. The engineered strain, which can growth with PET as sole carbon source, was used as biocatalyst for biodegradation of PET particles. A combinatorial processing based on whole-cell biocatalysts was constructed for biodegradation of PET. Compared with enzymes, the products can be used by strain growth and do not accumulated in culture solution. Thus, feedback inhibition of products can be avoided. When PET was treated with the alkaline strain under high pH conditions, the product concentration was higher and the size of PET particles decreased dramatically than that of the biocatalyst under neutral conditions. This shows that the method of combined processing of alkali and organisms is more efficient for biodegradation of PET. The novel approach of combinatorial processing of PET based on whole-cell biocatalysis provides an attractive avenue for the biodegradation of micplastics.

6.
ACS Appl Mater Interfaces ; 8(11): 6859-68, 2016 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-26915062

RESUMO

Premature drug release is a common drawback in stimuli-responsive drug delivery systems (DDS), especially if it depends on internal triggers, which are hard to control, or a single external stimulus, which can only have one function. Thus, many DDS systems have been reported that combined different triggers; however, limited success has been established in fine-tuning the release process, mainly due to the poor bioavailability and complexity of the reported designs. This paper reports the design of a hybrid microcapsule (h-MC) by a simple layer-by-layer technique comprising polysaccharides (sodium alginate, chitosan, and hyaluronic acid), iron oxide, and graphene oxide (GO). Electrostatic assembly of the oppositely charged polysaccharides and graphene sheets provided a robust structure in which to load drugs through pH control. The polysaccharide component ensured high biocompatibility, bioavailability, and tumor cells targeting. The alternative magnetic field and near-infrared laser triggerable Fe3O4@GO component provided for dual high-energy and high-penetration hyperthermia therapy. On-demand drug release from h-MC can be achieved by synchronizing these external triggers, making the release highly controllable. The synergistic effect of hyperthermia and chemotherapy was successfully confirmed in vitro and in vivo.


Assuntos
Compostos Férricos , Grafite , Hipertermia Induzida/métodos , Neoplasias Experimentais/terapia , Animais , Cápsulas , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacocinética , Compostos Férricos/farmacologia , Grafite/química , Grafite/farmacocinética , Grafite/farmacologia , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Chemistry ; 21(48): 17274-81, 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-26275063

RESUMO

Graphene oxide-wrapped gold nanorods (GO@AuNRs) offer efficient drug delivery as well as NIR laser photothermal therapy (PTT) in vitro and in vivo. However, no real-time observation of drug release has been reported to better understand the synergy of chemotherapy and PTT. Herein, surface-enhance Raman spectroscopy (SERS) is employed to guide chemo-photothermal cancer therapy by a two-step mechanism. In the presence of GO as an internal standard, SERS signals of DOX (doxorubicin) loaded onto GO@AuNRs are found to be pH-responsive. Both DOX and GO show strong SERS signals before the DOX@GO@AuNRs are endocytic. However, when the DOX@GO@AuNRs enter acidic microenvironments such as endosomes and/or lysosomes, the DOX signals start decreasing while the GO signals remain the same. This plasmonic antenna could be used to identify the appropriate time to apply the PTT laser during chemo-photothermal therapy.


Assuntos
Sistemas de Liberação de Medicamentos , Ouro/química , Grafite/química , Nanotubos/química , Neoplasias/tratamento farmacológico , Antibióticos Antineoplásicos/química , Doxorrubicina/farmacologia , Humanos , Análise Espectral Raman
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