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1.
Adv Healthc Mater ; 13(11): e2303667, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38178648

RESUMO

Currently, cisplatin resistance has been recognized as a multistep cascade process for its clinical chemotherapy failure. Hitherto, it remains challenging to develop a feasible and promising strategy to overcome the cascade drug resistance (CDR) issue for achieving fundamentally improved chemotherapeutic efficacy. Herein, a novel self-assembled nanoagent is proposed, which is constructed by Pt(IV) prodrug, cyanine dye (cypate), and gadolinium ion (Gd3+), for systematically conquering the cisplatin resistance by employing near-infrared (NIR) light activated mild-temperature hyperthermia in tumor targets. The proposed nanoagents exhibit high photostability, GSH/H+-responsive dissociation, preferable photothermal conversion, and enhanced cellular uptake performance. In particular, upon 785-nm NIR light irradiation, the generated mild temperature of ≈ 43 °C overtly improves the cell membrane permeability and drug uptake, accelerates the disruption of intracellular redox balance, and apparently enhances the formation of Pt-DNA adducts, thereby effectively overcoming the CDR issue and achieves highly improved therapeutic efficacy for cisplatin-resistant tumor ablation.


Assuntos
Cisplatino , Resistencia a Medicamentos Antineoplásicos , Hipertermia Induzida , Indóis , Propionatos , Cisplatino/farmacologia , Cisplatino/química , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Animais , Hipertermia Induzida/métodos , Camundongos , Linhagem Celular Tumoral , Raios Infravermelhos , Gadolínio/química , Gadolínio/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Camundongos Endogâmicos BALB C , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Camundongos Nus , Carbocianinas/química , Carbocianinas/farmacologia
2.
Acta Biomater ; 174: 177-190, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38070843

RESUMO

Wound infections hinder the healing process and potentially result in life-threatening complications, which urgently require rapid and timely detection and treatment pathogens during the early stages of infection. Here, an intelligent wound dressing was developed to enable in situ detection and elimination of pathogenic bacteria through a combination of point-of-care testing and antibacterial photodynamic therapy technology. The dressing is an injectable hydrogel composed of carboxymethyl chitosan and oxidized sodium alginate, with addition of 4-methylumphulone beta-D-glucoside (MUG) and up-converted nanoparticles coated with titanium dioxide (UCNPs@TiO2). The presence of bacteria can be visually detected by monitoring the blue fluorescence of 4-methylumbellione, generated through the reaction between MUG and the pathogen-associated enzyme. The UCNPs@TiO2 photosensitizers were synthesized and demonstrated high antibacterial activity through the generation of reactive oxygen species when exposed to near-infrared irradiation. Meanwhile, a smartphone-based portable detection system equipped with a self-developed Android app was constructed for in situ detection of pathogens in mere seconds, detecting as few as 103 colony-forming unit. Additionally, the dressing was tested in a rat infected wound model and showed good antibacterial activity and pro-healing ability. These results suggest that the proposed intelligent wound dressing has potential for use in the diagnosis and management of wound infections. STATEMENT OF SIGNIFICANCE: An intelligent wound dressing has been prepared for simultaneous in situ detection and elimination of pathogenic bacteria. The presence of bacteria can be visually detected by tracking the blue fluorescence of the dressing. Moreover, a smartphone-based detection system was constructed to detect and diagnose pathogenic bacteria before reaching the infection limit. Meanwhile, the dressing was able to effectively eliminate key pathogenic bacteria on demand through antibacterial photodynamic therapy under NIR irradiation. The proposed intelligent wound dressing enables timely detection and treatment of infectious pathogens at an early stage, which is beneficial for wound management.


Assuntos
Bactérias , Infecção dos Ferimentos , Ratos , Animais , Antibacterianos/farmacologia , Bandagens , Hidrogéis/farmacologia , Infecção dos Ferimentos/diagnóstico , Infecção dos Ferimentos/terapia
3.
Artigo em Inglês | MEDLINE | ID: mdl-35839332

RESUMO

The surface structure and topography of biomaterials play a crucial role in directing cell behaviors and fates. Meanwhile, asymmetric dressings that mimic the natural skin structure have been identified as an effective strategy for enhancing wound healing. Inspired by the skin structure and the superhydrophobic structure of the lotus leaf, an asymmetric composite dressing was obtained by constructing an asymmetric structure and wettability surface modification on both sides of the sponge based on electrospinning. Among them, the collagen and quaternized chitosan sponge was fabricated by freeze-drying, followed by an aligned poly(ε-caprolactone) (PCL)/gelatin nanofiber hydrophilic inner layer and hierarchical micronanostructure PCL/polystyrene microsphere highly hydrophobic outer layer constructed on each side of the sponge. The proposed asymmetric composite dressing combines topological morphology with the material's properties to effectively prevent bacterial colonization/infection and promote wound healing by directing cellular behavior. In vitro experimental results confirmed that the aligned nanofiber inner layer effectively promotes cell adhesion, proliferation, directed cell growth, and migration. Meanwhile, the sponge has good water absorption and antibacterial properties, while the biomimetic hydrophobic outer layer exhibits strong mechanical properties and resistance to bacterial adhesion. In vivo results showed that the composite dressing can reduce inflammatory response, prevent infection, accelerate angiogenesis and epithelial regeneration, and significantly accelerate the healing of severe burns. Thus, the proposed bionic asymmetric dressing is expected to be a promising candidate for severe burn wound healing.

4.
Biomater Sci ; 10(12): 3268-3281, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35583113

RESUMO

Multidrug-resistant bacteria infections frequently occur in wound care due to the excessive use of antibiotics. It can cause scar formation, wound closure delay, multiple organ failure, and high mortality. Here, a double network hydrogel with injectability, hemostasis, and antibacterial activity was developed to prompt multidrug-resistant bacteria infected wound healing. The double network hydrogel is composed of gelatin methacryloyl (GelMA), oxidized dextran (ODex), ε-polylysine (EPL), and bacitracin, and formed through the Schiff-base and UV-initiated crosslinking reaction. The injectable hydrogel with an adhesion effect could adapt to the irregular shape of the wound and possesses good hemostatic ability. The hydrogel presents good flexibility and rapid resilience due to its double network structure, and it can prompt cell proliferation and migration. In particular, the hydrogel has broad-spectrum in vitro antimicrobial activities against S. aureus, E. coli, and methicillin-resistant S. aureus (MRSA), and disrupts E. coli and MRSA biofilms. In vivo results demonstrated that the hydrogel can completely heal MRSA-infected wound in rats within 15 days, through inhibiting the growth of bacteria, accelerating skin tissue reepithelialization, collagen deposition, and angiogenesis, as well as adjusting the expression of CD31, α-SMA, and TNF-α. The findings of this study suggest that the presented hydrogel could enhance multidrug-resistant bacteria infected wound healing and mitigate antimicrobial resistance.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecção dos Ferimentos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Escherichia coli , Gelatina , Hemostasia , Hidrogéis/química , Metacrilatos , Ratos , Staphylococcus aureus , Cicatrização
5.
Angew Chem Int Ed Engl ; 61(14): e202116983, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35084798

RESUMO

Stimuli-responsive nanoagents, which simultaneously satisfy normal tissue clearance and tumor-specific responsive treatment, are highly attractive for precise cancer theranostics. Herein, we develop a unique template-induced self-assembly strategy for the exquisitely controlled synthesis of self-assembled lanthanide (Ln3+ ) nucleotide nanoparticles (LNNPs) with amorphous structure and tunable size from sub-5 nm to 105 nm. By virtue of the low-temperature (10 K) and high-resolution spectroscopy, the local site symmetry of Ln3+ in LNNPs is unraveled for the first time. The proposed LNNPs are further demonstrated to possess the ability for highly efficient loading and tumor-microenvironment-responsive release of doxorubicin. Particularly, sub-5 nm LNNPs not only exhibit excellent biocompatibility and predominant renal-clearance performance, but also enable efficient tumor retention. These findings reveal the great potential of LNNPs as a new generation of therapeutic platform to overcome the dilemma between efficient therapy and long-term toxicity of nanoagents for future clinical applications.


Assuntos
Elementos da Série dos Lantanídeos , Nanopartículas , Neoplasias , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Nucleotídeos , Microambiente Tumoral
6.
Talanta ; 231: 122243, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33965056

RESUMO

Rapid and accurate detection of phosphate (Pi) in complex biological fluid is of critical importance for timely warning of Pi accumulation and monitoring Pi related pathological process. Up to date, various luminescent probes have been developed for Pi determination in aqueous media. However, the huge obstacles of the current probes suffer from the inherent issues such as time-consuming, tedious preparation and unavoidable background interference during Pi detection. To circumvent this limitation, we proposed a universal and facile strategy to fabricate a novel sensitizer-Ln3+@surfactant micelle probe with time-resolved luminescent (TRL) superiority through the self-assembly of sensitizer, Ln3+ and surfactant. Through this design, the sensitizer-Ln3+ chelate can be encapsulated into the surfactant constructed micelle and Ln3+ luminescence can be substantially lighted up through the effective energy transfer from the coordinated sensitizer and the assistance of Triton X-100. Such high TRL signal can be sensitively and specifically quenched by Pi, which was attributed to the specific coordination competition between sensitizer and Pi towards Ln3+. Benefitting from the background-free interference and highly sensitive TRL response of the sensitizer-Ln3+@surfactant probe, we achieved the rapid, selective and sensitive detection of Pi in the range of 0.5-120 µM with a limit of detection (LOD) of 0.19 µM. Furthermore, the accuracy of the proposed method based on the Ln3+ involved micelle probes was further verified through the quantitation of Pi in real biological samples.


Assuntos
Elementos da Série dos Lantanídeos , Transferência de Energia , Limite de Detecção , Luminescência , Fosfatos
7.
Biomater Sci ; 9(3): 700-711, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33241806

RESUMO

Currently, the in situ on/off switch of PTT/PDT reagents for tumor treatment has evoked considerable interest in the field of cancer therapy. However, the actual PTT/PDT therapy efficacy in tumor treatment is largely restricted by the PTT/PDT reagents' aggregation issues during their release from the hydrophobic carrier to the hydrophilic tumor microenvironment. Thus, it remains a challenge to break through the therapy barrier caused by the PTT/PDT agent aggregation and achieve substantial improvement of anticancer efficacy. In this work, we developed a novel near-infrared (NIR) light-responsive and gas bubble-generated liposomal nanobomb (Cy/Ce6/CO2-Lip-FA) through the co-encapsulation of PTT/PDT reagents with gas precursor into the hydrophobic and hydrophilic regions of liposomes, respectively, in order to overcome the aggregation issues and substantially improve the synergistic PTT/PDT efficacy. Upon arrival at the tumor region, the PS phototoxicity of Cy/Ce6/CO2-Lip-FA could be effectively switched on through CO2 generation induced by the PTT effect of Cypate upon NIR irradiation. The gas bubble burst can remarkably suppress the aggregation of Cypate/Ce6 and extremely enhance the synergistic PTT/PDT efficacy. These results indicate that the proposed NIR-responsive and gas bubble-functionalized liposomal nanobomb is a highly promising platform for tumor treatment with better therapeutic efficacy.


Assuntos
Hipertermia Induzida , Neoplasias , Fotoquimioterapia , Humanos , Raios Infravermelhos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral
8.
Nanoscale ; 11(9): 3814-3826, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30600823

RESUMO

In cancer therapy, chemotherapeutic drugs frequently encounter multidrug resistance (MDR) induced by the overexpression of drug transporters such as P-glycoprotein (P-gp). Herein, in order to overcome MDR and improve the effectiveness of chemotherapy, we developed a novel pH-sensitive charge-reversal and NO generation liposomal system by modifying a pH-sensitive polymer (PEG-PLL-DMA) on the surface of cationic liposomes for delivering a NO donor (DETA NONOate) and a chemotherapy drug (paclitaxel, PTX) into MDR cells. The proposed liposomal system (PTX/NO/DMA-L) exhibited a distinctive charge-reversal capacity, which was negatively charged under physiological conditions (pH 7.4) but could reverse to positive charge in a tumor microenvironment (pH 6.5) due to the cleavable amide linkages formed between PEG-PLL and DMA, leading to the improvement of cell uptake. Once arrived in the endosomes and lysosomes (pH 5.0), DETA NONOate was triggered to decompose and release NO, which further promoted the quick release of PTX and inhibited the P-gp mediated efflux. The charge-reversal, NO generation and NO-triggered rapid release of drugs could significantly increase the accumulation of PTX in tumors and eventually improve the antitumor efficacy. These results indicate that this dual pH-sensitive liposomal system is a highly promising approach for chemotherapy and may pave a new avenue for overcoming MDR in cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Lipossomos/química , Óxido Nítrico/metabolismo , Paclitaxel/química , Células A549 , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Nus , Microscopia Confocal , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Paclitaxel/metabolismo , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Polímeros/química , Distribuição Tecidual , Transplante Heterólogo
9.
Colloids Surf B Biointerfaces ; 167: 104-114, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29631221

RESUMO

A charge-conversional and NIR responsive rapid release liposomal system (PSD/DOX/Cypate-BTSL) was developed to enhance therapeutic efficacy of cancer therapy. The cationic liposomes containing Cypate, doxorubicin (DOX) and NH4HCO3 were shielded by pH-sensitive poly(methacryloyl sulfadimethoxine) (PSD) through electrostatic interaction at pH 7.4. At the tumor site (pH 6.5), PSD was deshielded and the liposomes displayed pH-sensitive charge reversal capability. The DOX released from PSD/DOX/Cypate-BTSL with irradiation was markedly higher than the other groups, indicating NIR irradiation and NH4HCO3 had a significant effect on the drug release. After irradiation, the hyperthermia induced by Cypate could produce CO2 bubbles quickly on account of the decomposition of NH4HCO3, achieving the rapid drug release. In 4T1 cells, PSD/DOX/Cypate-BTSL improved cellular uptake and cytotoxicity with irradiation at pH 6.5. In vivo results implied that the liposomes with irradiation could efficiently enhance the tumor accumulation and antitumor efficacy, and reduce systemic side effects of DOX. In conclusion, PSD/DOX/Cypate-BTSL is a promising candidate as a carrier for synergistic effects of PTT and chemotherapy.


Assuntos
Tratamento Farmacológico/métodos , Raios Infravermelhos , Lipossomos/química , Fototerapia/métodos , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Bicarbonatos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Hipertermia Induzida , Camundongos Nus , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
10.
ACS Appl Bio Mater ; 1(6): 2030-2040, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34996265

RESUMO

Articular cartilage defects cannot adequately self-repair because of avascular and complex tissues. Although various scaffold materials have been reported to promote cartilage repair, challenges remain in this field. In the present study, an orientated microtubules scaffold that consisted of collagen, chitosan, silk fibroin, and polylysine-heparin sodium nanoparticles containing transforming growth factor ß1 (TGF-ß1), was constructed using a unidirectional freeze-drying method. The collagen/chitosan/0.5silk fibroin scaffolds showed optimal properties via the evaluation of physicochemical characterization, mechanical properties and biocompatibility. The collagen/chitosan/0.5silk fibroin scaffolds containing polylysine-heparin sodium nanoparticles loaded with TGF-ß1 (COL/CS/0.5SF-TPHNs) could control the slow release of TGF-ß1. Simultaneously, the in vitro COL/CS/0.5SF-TPHNs scaffolds exhibited not only an excellent biocompatibility to support mouse mesenchymal stem cells (mBMSCs) adhesion and proliferation, but also exhibited excellent repair effect in cartilage defects of rabbit models in vivo. Our results showed that the COL/CS/0.5SF-TPHNs scaffolds have the potential to induce articular cartilage formation, mainly because TGF-ß1 could induce the mBMSCs to differentiate into chondrocytes and osteoblasts. Consequently, the current study can achieve cartilage repair, and COL/CS/0.5SF-TPHNs scaffolds are expected to be potential composites for cartilage tissue engineering.

11.
ACS Biomater Sci Eng ; 4(3): 1055-1063, 2018 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33418789

RESUMO

Biocompatible, near-infrared luminescent gold nanoclusters were synthesized in situ using as-prepared chitosan grafted with N-acetyl-l-cysteine (NAC-CS). The fluorescent gold nanoclusters coated with chitosan-N-acetyl-l-cysteine (AuNCs@NAC-CS) were aggregated by multiple ultrasmall gold nanoclusters closing with each other, with strong fluorescence emission at 680 nm upon excitation at 360 nm. AuNCs@NAC-CS did not display any appreciable cytotoxicity on cells even at a concentration of 1.0 mg mL-1. AuNCs@NAC-CS were more insensitive to H2O2 and trypsin compared with fluorescent gold nanoclusters coated with Albumin Bovine V (AuNCs@BSA), which make them have long time imaging in HeLa cells. Furthermore, the obvious fluorescence signal of AuNCs@NAC-CS appeared in the liver and kidney of the normal mice after 6 h injection. And the fluorescence intensity decreased after that because of the highly efficient clearance characteristics of ultrasmall nanoparticles. These findings demonstrated that AuNCs@NAC-CS possessed good fluorescence, low cytotoxicity, and low sensitivity to some content of cells, allowing imaging of the living cells.

12.
Int J Nanomedicine ; 12: 4225-4239, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28652729

RESUMO

To design a rapid release liposomal system for cancer therapy, a NIR responsive bubble-generating thermosensitive liposome (BTSL) system combined with photothermal agent (Cypate), doxorubicin (DOX), and NH4HCO3 was developed. Cypate/DOX-BTSL exhibited a good aqueous stability, photostability, and photothermal effect. In vitro release suggested that the amounts of DOX released from BTSL were obviously higher than that of (NH4)2SO4 liposomes at 42°C. After NIR irradiation, the hyperthermic temperature induced by Cypate led to the decomposition of NH4HCO3 and the generation of a large number of CO2 bubbles, triggering a rapid release of drugs. Confocal laser scanning microscope and acridine orange staining indicated that Cypate/DOX-BTSL upon irradiation could facilitate to disrupt the lysosomal membranes and realize endolysosomal escape into cytosol, improving the intracellular uptake of DOX clearly. MTT and trypan blue staining implied that the cell damage of Cypate/DOX-BTSL with NIR irradiation was more severe than that in the groups without irradiation. In vivo results indicated that Cypate/DOX-BTSL with irradiation could dramatically increase the accumulation of DOX in tumor, inhibit tumor growth, and reduce systemic side effects of DOX. These data demonstrated that Cypate/DOX-BTSL has the potential to be used as a NIR responsive liposomal system for a rapid release of drugs in thermochemotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Lipossomos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Bicarbonatos/química , Bicarbonatos/farmacocinética , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Feminino , Humanos , Indóis/química , Células MCF-7 , Camundongos Endogâmicos BALB C , Propionatos/química , Temperatura , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Colloids Surf B Biointerfaces ; 151: 189-195, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28012407

RESUMO

Wound treatment should meet the challenge both of preventing infection and promoting wound healing. To design a sequential delivery system for wound healing, PLGA-glycol chitosan (GC) core-shell microspheres containing chlorhexidine acetate (CHA) at the GC shell and bFGF in the core of PLGA microspheres were fabricated using emulsion-solvent evaporation method. SEM showed that the microspheres were all spherical in shape with a smooth surface. The average size of PLGA-GC microspheres increased due to the GC coating on the surface. The results of release profiles and fluorescence images indicated that PLGA-GC microspheres had an ability to deliver drugs in sequence. The CHA was rapidly released, whereas the proteins presented a sustained release. The release behavior could be modulated by changing the GC amount. Antibacterial assay and cell proliferation tests suggested that the released CHA and bFGF retained their antimicrobial activity and bioactivity during preparation. The microspheres exhibited non-cytotoxicity against 3T3 cells and had a good biocompatibility. These results demonstrated that PLGA-GC core-shell microspheres could be a promising controlled release system of delivering drugs and proteins in sequence for wound healing.


Assuntos
Quitosana/química , Clorexidina/administração & dosagem , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Glicóis/química , Ácido Láctico/química , Ácido Poliglicólico/química , Células 3T3 , Animais , Antibacterianos/química , Materiais Biocompatíveis/química , Proliferação de Células , Clorexidina/química , Sistemas de Liberação de Medicamentos , Fator 2 de Crescimento de Fibroblastos/química , Camundongos , Microscopia Eletrônica de Varredura , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Cicatrização
15.
Colloids Surf B Biointerfaces ; 136: 1098-106, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26618451

RESUMO

To design a scaffold controlled release system for skin tissue engineering, fish collagen/chitosan/chondroitin sulfate scaffolds were fabricated by freeze-drying and incorporated with bFGF-loaded PLGA microspheres (MPs). SEM showed that the scaffolds exhibited an interconnected porous structure, and the spherical MPs were uniformly distributed into the scaffolds. The higher swelling and degradation rate of scaffolds/MPs could lead to a higher diffusion rate of MPs from the scaffolds, causing an increase in the protein release. The release rate of proteins could be adjusted by the size of MPs and the ratio of collagen to chitosan of scaffolds. Circular dichroism spectroscopy and MTT of bFGF after release indicated that the released bFGF retained its structural integrity and bioactivity during preparation. Cell proliferation and in vivo evaluation results suggested that the scaffolds/MPs had a good biocompatibility and an ability to promote fibroblast cell proliferation and skin tissue regeneration. These results demonstrated that this scaffold/MP controlled release system has the potential for skin tissue engineering.


Assuntos
Colágeno , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Ácido Láctico/administração & dosagem , Microesferas , Ácido Poliglicólico/administração & dosagem , Pele/crescimento & desenvolvimento , Engenharia Tecidual , Alicerces Teciduais , Animais , Carpas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos
16.
J Nanosci Nanotechnol ; 15(7): 4844-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26373045

RESUMO

Single-wall carbon nanotubes (SWNTs) have attractive biochemical properties such as strong cell adhesion and protein absorption, which are very useful for a cell cultivation scaffold. In this study, collagen/SWNT-COOHs nanocomposite films composed of regenerated fish collagen and SWNT-COOHs (0, 0.5, 1.0 and 2.0 weight percent) were prepared by mixing solubilized pepsin-soluble collagen with solutions of SWNT-COOHs. Morphological observation by SEM indicated the homogenous dispersion of SWNT-COOHs in the collagen matrix. The application of FTIR confirmed that the process we applied to prepare the composites did not destroy the native structures of collagen and composites were crosslinked by D-ribose. The biocompatibility was evaluated in vitro using SD rat bone marrow stem cells (BMSCs). Compared with films without transforming growth factor beta 1 (TGF-ß1), films with TGF-ß1 had superior performance on promotion of cell growth. Compared with pure collagen film with TGF-ß1, SWNT-containing films might promote cellular functions by adsorbing more growth factors. In conclusion, the study suggested that the collagen/SWNT-COOHs nanocomposite films with TGF-ß1 were expected to be useful scaffolds in cartilage tissue engineering.


Assuntos
Células da Medula Óssea/metabolismo , Membranas Artificiais , Células-Tronco Mesenquimais/metabolismo , Nanotubos de Carbono/química , Alicerces Teciduais/química , Fator de Crescimento Transformador beta1/farmacologia , Animais , Células da Medula Óssea/citologia , Colágeno/química , Matriz Extracelular/química , Proteínas Imobilizadas/farmacologia , Células-Tronco Mesenquimais/citologia , Camundongos , Nanocompostos/química , Ratos , Ratos Sprague-Dawley
17.
Colloids Surf B Biointerfaces ; 135: 581-587, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26320569

RESUMO

Traditional tissue engineering procedures are expensive and time consuming. Facilitated endogenous tissue engineering (FETE) provides a solution that can avoid the ex vivo culture of autologous cells and initiate in situ reparative endogenous repair processes in vivo. This method involves fabricating a porous scaffold that mimics the environment present during the bone formation process, consisting of components that provide biomimetic interfacial interactions to cells. After the scaffold is implanted, progenitor cells provided by autologous bone marrow and surrounding tissues then differentiate to bone cells under the direction of the in situ scaffold. This paper reports a biomimetic method to prepare a hierarchically structured hybrid scaffold. Bone-like nano hydroxyapatite (HA) was crystallized from a collagen and chitosan (CC) matrix to form a porous scaffold. The in vivo study demonstrates that this nanohybrid scaffold supports excellent bone repair. This means that the FETE approach, in which the cell culture portion of traditional tissue engineering takes place in vivo, can promote the intrinsic regenerative potential of endogenous tissues.


Assuntos
Regeneração Óssea , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Células Cultivadas , Quitosana/química , Colágeno/química , Durapatita/química , Masculino , Porosidade , Coelhos , Células-Tronco
18.
Eur J Pharm Sci ; 77: 154-60, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26093052

RESUMO

The purpose of this study was to improve the solubility and bioavailability of glimepiride (GLMP) by utilizing hydrotropy technique. Meglumine (MU) as a hydrotrope could form the stable complex with glimepiride. The optimal glimepiride and meglumine (GLMP-MU) complex powder was obtained by using lyophilization. GLMP-MU powder was characterized by Fourier transform infrared spectroscopy (FT IR), X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC). The formation of hydrogen bond between glimepiride and meglumine was confirmed by FT IR. The XRD studies indicated the amorphous state of glimepiride was appeared in the GLMP-MU. The DSC results were further confirmed GLMP-MU complex was prepared successfully. Moreover, the in vitro drug release rate of GLMP-MU powder was dramatically faster than that of glimepiride. Meanwhile, the AUC of GLMP-MU solution at an i.g./or i.v. dose of 5mg/kg in rat was significantly higher than that of the glimepiride suspensions. Together our results showed that hydrotropy technique was a simple and effective method to increase the solubility of glimepiride.


Assuntos
Hipoglicemiantes/farmacocinética , Compostos de Sulfonilureia/farmacocinética , Animais , Disponibilidade Biológica , Feminino , Difração de Pó , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Food Chem ; 181: 170-8, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25794736

RESUMO

The dependence of the interaction between bovine serum albumin (BSA) and two cinchona alkaloids, quinine (QN) and quinidine (QD), on the absolute configuration of these stereoisomers has been comprehensively studied. The FTIR spectra showed that QN and QD interacted with both CO and C-N groups of BSA, resulting in changes to the secondary structure of the protein. Fluorescence quenching of BSA by the stereoisomers revealed lower efficiency for QD in quenching the Trp emission of BSA when compared to QN. Further analysis accurately described the different binding behaviors and recognition discrepancies of QN and QD towards BSA, which was reflected through binding affinities, driving forces, energy changes and conformational changes during the ligand-protein interactions. Synchronous fluorescence further proved that QD was farther from Trp and Tyr than that of QN. This work could provide basic data for clarifying the binding interaction, metabolism and distribution of cinchona alkaloid stereoisomers in vivo.


Assuntos
Alcaloides de Cinchona/química , Soroalbumina Bovina/química , Análise Espectral/métodos , Animais , Bovinos , Ligação Proteica , Estrutura Secundária de Proteína , Estereoisomerismo
20.
Colloids Surf B Biointerfaces ; 128: 339-346, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25784300

RESUMO

The objective of this study was to design a drug delivery system consisting of biotinylated cholesterol-modified glycol chitosan (Bio-CHGC) nanoparticles and fish collagen/chitosan (Col/Ch) film for localized chemotherapy. Bio-CHGC was synthesized, and then its self-assembled nanoparticles were prepared by probe sonication. Doxorubicin (DOX)-loaded Bio-CHGC (DBC) nanoparticles prepared by dialysis had spherical shape, and their sizes were in the range of 330-397 nm. Col/Ch/DBC nanoparticle films were fabricated by freeze-drying. SEM showed that the DBC nanoparticles were uniformly distributed into the films, and the films retained their structural integrity. A higher degradation and swelling rate of the drug films led to a higher diffusion rate of the nanoparticles from the films, resulting in an increase in the drug release from nanoparticles. The release of DOX from the films or Bio-CHGC nanoparticles was sensitive to the pH value of the release medium. In addition, the DOX release ratio of the drug films was lower than that of the nanoparticles alone, suggesting that the drug films had a double-sustained effect on the drug release. MTT assay implied that the DBC nanoparticle film showed a higher inhibitory ratio than the film containing nanoparticles without biotin, indicating that biotin moieties in the nanoparticles played an important role in exerting a cytotoxic effect. These data demonstrate that Col/Ch/DBC nanoparticle film has the potential to be used as a localized delivery system for hydrophobic antitumor drugs.


Assuntos
Quitosana/química , Colágeno/química , Portadores de Fármacos , Proteínas de Peixes/química , Nanopartículas/química , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Biotinilação , Sobrevivência Celular/efeitos dos fármacos , Diálise , Difusão , Doxorrubicina/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Peixes , Liofilização , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Nanopartículas/ultraestrutura , Tamanho da Partícula , Sonicação
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