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1.
Membranes (Basel) ; 14(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38535280

RESUMO

Proton ceramic fuel cells offer numerous advantages compared with conventional fuel cells. However, the practical implementation of these cells is hindered by the poor sintering activity of the electrolyte. Despite extensive research efforts to improve the sintering activity of BCZY, the systematic exploration of the utilization of NiO as a sintering additive remains insufficient. In this study, we developed a novel BaCe0.55Zr0.35Y0.1O3-δ (BCZY) electrolyte and systematically investigated the impact of adding different amounts of NiO on the sintering activity and electrochemical performance of BCZY. XRD results demonstrate that pure-phase BCZY can be obtained by sintering the material synthesized via solid-state reaction at 1400 °C for 10 h. SEM analysis revealed that the addition of NiO has positive effects on the densification and grain growth of BCZY, while significantly reducing the sintering temperature required for densification. Nearly fully densified BCZY ceramics can be obtained by adding 0.5 wt.% NiO and annealing at 1350 °C for 5 h. The addition of NiO exhibits positive effects on the densification and grain growth of BCZY, significantly reducing the sintering temperature required for densification. An anode-supported full cell using BCZY with 0.5 wt.% NiO as the electrolyte reveals a maximum power density of 690 mW cm-2 and an ohmic resistance of 0.189 Ω cm2 at 650 °C. Within 100 h of long-term testing, the recorded current density remained relatively stable, demonstrating excellent electrochemical performance.

2.
Microbiol Spectr ; 11(6): e0200123, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37861315

RESUMO

IMPORTANCE: Bacterial surface glycans are an attractive therapeutic target in response to antibiotics; however, current knowledge of the corresponding mechanisms is rather limited. Antimicrobial susceptibility testing, genome sequencing, and MALDI-TOF MS, commonly used in recent years to analyze bacterial resistance, are unable to rapidly and efficiently establish associations between glycans and resistance. The discovery of new antimicrobial strategies still requires the introduction of promising analytical methods. In this study, we applied lectin microarray technology and a machine-learning model to screen for important glycan structures associated with carbapenem-resistant P. aeruginosa. This work highlights that specific glycopatterns can be important biomarkers associated with bacterial antibiotic resistance, which promises to provide a rapid entry point for exploring new resistance mechanisms in pathogens.


Assuntos
Anti-Infecciosos , Infecções por Pseudomonas , Humanos , Pseudomonas aeruginosa/genética , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecções por Pseudomonas/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Biomarcadores , Testes de Sensibilidade Microbiana , Polissacarídeos
3.
J Biomed Biotechnol ; 2011: 854872, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21331356

RESUMO

The purpose of this study was to prepare a novel paclitaxel (PTX) microemulsion containing a reduced amount of Cremophor EL (CrEL) which had similar pharmacokinetics and antitumor efficacy as the commercially available PTX injection, but a significantly reduced allergic effect due to the CrEL. The pharmacokinetics, biodistribution, in vivo antitumor activity and safety of PTX microemulsion was evaluated. The results of pharmacokinetic and distribution properties of PTX in the microemulsion were similar to those of the PTX injection. The antitumor efficacy of the PTX microemulsion in OVCRA-3 and A 549 tumor-bearing animals was similar to that of PTX injection. The PTX microemulsion did not cause haemolysis, erythrocyte agglutination or simulative reaction. The incidence and degree of allergic reactions exhibited by the PTX microemulsion group, with or without premedication, were significantly lower than those in the PTX injection group (P < .01). In conclusion, the PTX microemulsion had similar pharmacokinetics and anti-tumor efficacy to the PTX injection, but a significantly reduced allergic effect due to CrEL, indicating that the PTX microemulsion overcomes the disadvantages of the conventional PTX injection and is one way of avoiding the limitations of current injection product while providing suitable therapeutic efficacy.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Glicerol/análogos & derivados , Paclitaxel/química , Paclitaxel/farmacologia , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/química , Cães , Emulsões/efeitos adversos , Emulsões/química , Feminino , Glicerol/efeitos adversos , Glicerol/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Paclitaxel/efeitos adversos , Paclitaxel/farmacocinética , Tamanho da Partícula , Veículos Farmacêuticos/efeitos adversos , Veículos Farmacêuticos/química , Coelhos , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
4.
AAPS PharmSciTech ; 11(2): 752-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20443090

RESUMO

The purpose of this present study was to evaluate the antiangiogenic activity of sterically stabilized liposomes containing paclitaxel (SSL-PTX). The SSL-PTX was prepared by the thin-film method. The release of paclitaxel from SSL-PTX was analyzed using a dialysis method. The effect of SSL-PTX on endothelial cell proliferation and migration was investigated in vitro. The antitumor and antiangiogenic activity of SSL-PTX was evaluated in MDA-MB-231 tumor xenograft growth in BALB/c nude mice. The release of paclitaxel from SSL-PTX was 22% within 24 h. Our in vitro results indicated that SSL-PTX could effectively inhibit the endothelial cell proliferation and migration at a concentration-dependent manner. We also observed that metronomic SSL-PTX induced marked tumor growth inhibition in MDA-MB-231 xenograft model via the antiangiogenic mechanism, unlike that in paclitaxel injection (Taxol) formulated in Cremophor EL (CrEL). Overall, our results suggested that metronomic chemotherapy with low-dose, CrEL-free SSL-PTX should be feasible and effective.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Preparações de Ação Retardada/síntese química , Lipossomos/química , Paclitaxel/administração & dosagem , Paclitaxel/química , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/química , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Difusão , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Resultado do Tratamento
5.
Int J Pharm ; 535(1-2): 164-171, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29107614

RESUMO

Hydroxysafflor yellow A (HSYA) is the main bioactive flavonoid extracted from the flower of Carthamus tinctorius L., which is widely used in traditional Chinese medicine for the treatment of myocardial ischemia and cerebral ischemia. HSYA has high water solubility but poor intestinal membrane permeability, resulting in low oral bioavailability. Currently, only HSYA sodium chloride injection has been approved for clinical use and oral formulations are urgently needed. In this study, HSYA solid lipid nanoparticles (SLNs) with the structure of w/o/w were prepared by a warm microemulsion process using approved drug excipients for oral delivery to increase the oral absorption of HSYA. The optimized HSYA SLNs are spherical with an average size of 214nm and the encapsulation efficiency is 55%. HSYA SLNs exhibited little cytotoxicity in Caco-2 and Hela cells, but increased the oral absorption of HSYA about 3.97-fold in rats, compared to HSYA water solution. In addition, cycloheximide pretreatment significantly decreased the oral absorption of HSYA delivered by SLNs. Importantly, the pharmacodynamics evaluation demonstrated that SLNs further decreased the infarct areas in rats. In conclude, SLNs could be a promising delivery system to enhance the oral absorption and pharmacological activities of HSYA.


Assuntos
Chalcona/análogos & derivados , Portadores de Fármacos/química , Flavonoides/administração & dosagem , Lipídeos/química , Nanopartículas/química , Quinonas/administração & dosagem , Administração Oral , Animais , Isquemia Encefálica/tratamento farmacológico , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Chalcona/administração & dosagem , Chalcona/farmacologia , Chalcona/uso terapêutico , Liberação Controlada de Fármacos , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Células HeLa , Humanos , Masculino , Medicina Tradicional Chinesa , Absorção pela Mucosa Oral , Quinonas/farmacologia , Quinonas/uso terapêutico , Ratos Sprague-Dawley
6.
J Control Release ; 234: 90-7, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-27212103

RESUMO

Successful transfection of plasmid DNA (pDNA) requires intranuclear internalization of pDNA effectively and the nuclear envelope appears to be one of the critical intracellular barriers for polymer mediated pDNA delivery. Polyethylenimine (PEI), as the classic cationic polymer, compact the negatively charged pDNA tightly and make up stable polyplexes. The polyplexes are too large to enter the nuclear through nuclear pores and it is believed that the nuclear envelope breakdown in mitosis could facilitate the nuclear entry of polyplexes. To jump the nuclear envelope barrier, we used a selective and reversible CDK1 inhibitor RO-3306 to control the G2/M transition of the cell cycle and increased the proportion of mitotic cells which have disappeared nuclear envelope during transfection. Herein, we show that RO-3306 remarkably increases the transfection efficiency of PEI polyplexes through enhanced nuclear localization of PEI and pDNA. However, RO-3306 is less effective to the charge-reversal polymer poly[(2-acryloyl)ethyl(p-boronic acid benzyl)diethylammonium bromide] (B-PDEAEA) which responses to cellular stimuli and releases free pDNA in cytoplasm. Our findings not only offer new opportunities for improving non-viral based gene delivery but also provide theoretical support for the rational design of novel functional polymers for gene delivery. We also report current data showing that RO-3306 synergizes TRAIL gene induced apoptosis in cancer cells.


Assuntos
Proteína Quinase CDC2/antagonistas & inibidores , Portadores de Fármacos/química , Membrana Nuclear/efeitos dos fármacos , Polietilenoimina/química , Inibidores de Proteínas Quinases/farmacologia , Quinolinas/farmacologia , Tiazóis/farmacologia , Transfecção/métodos , Células A549 , Ciclo Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , DNA/administração & dosagem , DNA/genética , Proteínas de Fluorescência Verde/administração & dosagem , Proteínas de Fluorescência Verde/genética , Células HeLa , Humanos , Membrana Nuclear/metabolismo
7.
Biomaterials ; 34(4): 1102-14, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23127332

RESUMO

In the present study, we prepared NGR-modified sterically stabilized liposomes containing paclitaxel (NGR-SSL-PTX) in order to evaluate their potential targeting to aminopeptidase N receptors expressed on tumor endothelial cells and the tumor cell surface and its anti-angiogenic activity following metronomic administration. NGR-SSL-PTX was prepared by a thin-film hydration method. The in vitro targeting characteristics of NGR-modified liposomes on HUVEC (human umbilical vein endothelial cells), HT1080 (human fibrosarcoma cells) and MCF-7 (human breast adenocarcinoma cells) were then investigated. The effect of NGR-SSL-PTX on HUVEC proliferation and migration was also tested. The pharmacokinetics of NGR-SSL-PTX was studied in rats. The in vivo targeting activity of NGR-modified liposomes was investigated in HT1080 tumor-bearing mice. The anti-tumor activity of NGR-SSL-PTX following metronomic administration was evaluated in HT1080 tumor-bearing mice in vivo. The targeting activity of the NGR-modified liposomes was demonstrated by in vitro flow cytometry and confocal microscopy as well as in vivo confocal immunofluorescence microscopy and bio-distribution experiments. The results of endothelial cell proliferation and migration and microvessel density (MVD) confirmed the anti-angiogenic activity of NGR-SSL-PTX in vitro and in vivo. The sustained circulation of NGR-SSL-PTX was shown in the pharmacokinetic study. NGR-SSL-PTX is able to improve treatment efficacy producing the most significant anti-tumor activity and anti-angiogenic following metronomic administration.


Assuntos
Fibrossarcoma/tratamento farmacológico , Fibrossarcoma/metabolismo , Lipossomos/química , Nanocápsulas/administração & dosagem , Oligopeptídeos/química , Paclitaxel/administração & dosagem , Paclitaxel/farmacocinética , Administração Metronômica , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacocinética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacocinética , Difusão , Feminino , Fibrossarcoma/patologia , Humanos , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanocápsulas/química , Especificidade de Órgãos , Paclitaxel/química , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Resultado do Tratamento
8.
Biomaterials ; 33(8): 2508-20, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22197569

RESUMO

The acidic pH in tumor tissues could be used for targeting solid tumors. In the present study, we designed a tumor-specific pH-responsive peptide H(7)K(R(2))(2), which could respond to the acidic pH in tumor tissues, and prepared H(7)K(R(2))(2)-modified polymeric micelles containing paclitaxel (PTX-PM-H(7)K(R(2))(2)) in order to evaluate their potential targeting of tumor cells and tumor endothelial cells and their anti-tumor activity in mice with tumor cells. PTX-PM-H(7)K(R(2))(2) was prepared by a thin-film hydration method. The in vitro release of PTX from PTX-PM-H(7)K(R(2))(2) was tested. The in vitro targeting characteristics of H(7)K(R(2))(2)-modified polymeric micelles on HUVEC (human umbilical vein endothelial cells) and MCF-7 (human breast adenocarcinoma cells) were evaluated. The in vivo targeting activity of H(7)K(R(2))(2)-modified polymeric micelles and the in vivo anti-tumor activity of PTX-PM-H(7)K(R(2))(2) were also investigated in MCF-7 tumor-bearing mice. The released PTX from the PTX-PM-H(7)K(R(2))(2) was not affected by the pH. The targeting activity of the H(7)K(R(2))(2)-modified polymeric micelles was demonstrated by in vitro flow cytometry and confocal microscopy as well as in vivo biodistribution. PTX-PM-H(7)K(R(2))(2) produced very marked anti-tumor and anti-angiogenic activity in MCF-7 tumor-bearing mice in vivo.


Assuntos
Micelas , Neoplasias/patologia , Paclitaxel/farmacologia , Peptídeos/química , Polímeros/química , Animais , Carbocianinas/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Feminino , Citometria de Fluxo , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Microvasos/efeitos dos fármacos , Microvasos/patologia , Neoplasias/irrigação sanguínea , Neovascularização Patológica/patologia , Paclitaxel/química , Tamanho da Partícula , Distribuição Tecidual/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Drug Deliv ; 2011: 841054, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21490756

RESUMO

The purpose of the present study was to prepare a novel domperidone hydrogel. The domperidone dispersion was prepared by the solvent evaporation method. The characteristics of domperidone dispersion were measured by dynamic light scattering (DLS), scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffractometry, and solubility test, respectively. Domperidone hydrogel was prepared by directly incorporating the domperidone dispersion in Carbopol hydrogel to increase its mucoadhesive properties to gastrointestinal tract (GIT). The in vivo pharmacokinetic and pharmacodynamic studies were investigated to evaluate the relative oral bioavailability and the propulsion efficacy of domperidone hydrogel as compared with market domperidone tablet (Motilium tablet). The particle size of domperidone dispersion in distilled water was 454.0 nm. The results of DSC and X-ray indicated that domperidone in dispersion was in amorphous state. The solubility of domperidone in the dispersion in distilled water, pH of 1, 5, and 7 buffer solution was 45.7-, 63.9-, 13.1-, and 3.7-fold higher than that of raw domperidone, respectively. The area under the plasma concentration curve (AUC(0-24)) in domperidone hydrogel was 2.2-fold higher than that of tablet. The prolonged propulsion efficacy in the domperidone hydrogel group compared to that in tablet group was observed in the pharmacodynamic test.

10.
J Drug Target ; 19(5): 382-90, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20677914

RESUMO

Aminopeptidase N (APN), recognized by Asn-Gly-Arg (NGR) peptides, is expressed in the pericytes associated with the BBB, and the main objective of this study is to confirm the hypothesis that NGR-modified DSPE-PEG micelles containing paclitaxel (NGR-M-PTX) can bind to and kill brain tumor angiogenic blood vessels and penetrate into the brain tumor interstitial space, resulting in direct cell death. NGR-M-PTX is prepared by a thin-film hydration method. The in vitro targeting characteristics of NGR-modified micelles on BMEC (murine brain microvascular endothelial cells) were investigated. The effect of NGR-M-PTX on BMEC proliferation and the cytotoxicity of NGR-M-PTX in C6 glioma cells were also tested. The antitumor activity NGR-M-PTX was evaluated in C6 glioma tumor-bearing rats in vivo. The particle size of NGR-M-PTX was approximately 54.2 nm. The drug encapsulation efficiency of NGR-M-PTX was 82.11 ± 2.82%. The cellular coumarin-6 level of NGR-M-coumarin-6 in the BMEC was about 2.2-fold higher than that of M-coumarin-6. BMEC proliferation was significantly inhibited by NGR-M-PTX. NGR-M-PTX had a much lower IC(50) value than M-PTX and free drug. The growth of C6 glioma tumor was markedly inhibited by NGR-M-PTX compared with Taxol. In conclusion, our results show that antiangiogenic therapy using NGR-M-PTX exhibits potent in vivo antitumor activity in a C6 glioma-bearing animal model.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Portadores de Fármacos/química , Glioma/tratamento farmacológico , Oligopeptídeos/química , Paclitaxel/uso terapêutico , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Inibidores da Angiogênese/administração & dosagem , Animais , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/enzimologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Células Endoteliais/efeitos dos fármacos , Citometria de Fluxo , Glioma/irrigação sanguínea , Glioma/enzimologia , Glutamil Aminopeptidase/metabolismo , Masculino , Camundongos , Micelas , Microscopia de Fluorescência , Transplante de Neoplasias , Paclitaxel/administração & dosagem , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley
11.
Biomaterials ; 31(22): 5855-64, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20430438

RESUMO

Considering the effects of conjugated linoleic acid (CLA) on anti-tumor and anti-angiogenic in brain tumor, synergistic anti-tumor activity with taxane as well as potential activity for transporting chemotherapeutic agents across the blood-brain barrier (BBB), the purpose of this study was to synthesize CLA-paclitaxel (CLA-PTX) conjugate which could reach to the brain tissue and target brain tumor. The CLA was covalently linked to PTX. The conjugate was stable in PBS and rat plasma in vitro and had no microtubule assembly activity in solution and slight effect of arresting cell cycle progression at the G(2)-M phase. The in vitro cytotoxicity of conjugate was lower than that of PTX (p < 0.05). The conjugate showed higher cellular uptake efficiency on C6 glioma cells. The entire pharmacokinetic index revealed the significant enhancement of the conjugate pharmacokinetics compared with that in PTX (p < 0.01). The conjugate, unlike PTX, could distribute in brain tissue and retained higher concentrations throughout 360 h. The anti-tumor efficacy in brain tumor-bearing rats after administering conjugate was significantly higher than that after giving Taxol (p < 0.01). In conclusion, this CLA-PTX conjugate showed great potential to become a new prodrug of PTX and the methodology can be applied to other anticancer drugs.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Ácidos Linoleicos Conjugados/química , Ácidos Linoleicos Conjugados/uso terapêutico , Paclitaxel/química , Paclitaxel/uso terapêutico , Animais , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacocinética , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glioma/patologia , Ácidos Linoleicos Conjugados/síntese química , Ácidos Linoleicos Conjugados/farmacocinética , Masculino , Paclitaxel/síntese química , Paclitaxel/farmacocinética , Ratos , Ratos Sprague-Dawley , Tubulina (Proteína)/metabolismo
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