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1.
J Nanosci Nanotechnol ; 19(4): 2329-2333, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486993

RESUMO

In this work, we prepared basalt based nanostructured zeolite 13X by alkali fusion and hydrothermal synthesis process. The sample prepared was characterized using XRD, SEM, and low-temperature nitrogen analysis. The adsorption equilibrium and kinetic characteristics of ammonia nitrogen (NH+4-N) and phosphate phosphorus (PO3-4-P) were investigated. It was found that the basalt based nanostructured zeolite 13X showed high adsorption capacities for NH+4-N (75 mg/g) and PO3-4-P (25 mg/g) under the experimental conditions used. Our results demonstrate that basalt based zeolite 13X can be a good alternative adsorbent for the simultaneously removal of NH+4-N and PO3-4-P from aqueous solution.

2.
J Mater Sci Mater Med ; 27(4): 66, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26886814

RESUMO

The aim of this study was to evaluate antiproliferative sirolimus- and antioxidative alpha-lipoic acid (ALA)-eluting stents using biodegradable polymer [poly-L-lactic acid (PLA)] in a porcine coronary overstretch restenosis model. Forty coronary arteries of 20 pigs were randomized into four groups in which the coronary arteries had a bare metal stent (BMS, n = 10), ALA-eluting stent with PLA (AES, n = 10), sirolimus-eluting stent with PLA (SES, n = 10), or sirolimus- and ALA-eluting stent with PLA (SAS, n = 10). A histopathological analysis was performed 28 days after the stenting. The ALA and sirolimus released slowly over 30 days. There were no significant differences between groups in the injury or inflammation score; however, there were significant differences in the percent area of stenosis (56.2 ± 11.78% in BMS vs. 51.5 ± 12.20% in AES vs. 34.7 ± 7.23% in SES vs. 28.7 ± 7.30% in SAS, P < 0.0001) and fibrin score [1.0 (range 1.0-1.0) in BMS vs. 1.0 (range 1.0-1.0) in AES vs. 2.0 (range 2.0-2.0) in SES vs. 2.0 (range 2.0-2.0) in SAS, P < 0.0001] between the four groups. The percent area of stenosis based on micro-computed tomography corresponded with the restenosis rates based on histopathological stenosis in different proportions in the four groups (54.8 ± 7.88% in BMS vs. 50.4 ± 14.87% in AES vs. 34.5 ± 7.22% in SES vs. 28.9 ± 7.22% in SAS, P < 0.05). SAS showed a better neointimal inhibitory effect than BMS, AES, and SES at 1 month after stenting in a porcine coronary restenosis model. Therefore, SAS with PLA can be a useful drug combination for coronary stent coating to suppress neointimal hyperplasia.


Assuntos
Reestenose Coronária/terapia , Stents Farmacológicos , Sirolimo/farmacologia , Ácido Tióctico/farmacologia , Animais , Fibroblastos , Ratos , Sirolimo/química , Suínos , Ácido Tióctico/química , Resultado do Tratamento
3.
Mol Pharm ; 12(7): 2352-64, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-26029979

RESUMO

To increase cellular uptake and endosomal escape efficiency, various methods have been studied to efficiently deliver plasmid DNA (pDNA) into the cell. Here, we designed a histidylated arginine-grafted bioreducible polymer (HABP) as a nonviral gene carrier using different ratios of histidine and arginine-grafted bioreducible poly(cystaminebis(acrylamide)-diaminohexane) (poly(CBA-DAH)), known as ABP, to increase cellular uptake and endosomal escape efficiency. HABPs consist of arginine (cell penetrating functionality), histidine (endosome buffering functionality), and a disulfide bond backbone (bioreducible functionality in cytoplasm). These components result in the following: (1) polyplexes are easily taken up by cells, (2) polyplexes can easily escape from the endosome into the cytosol, and (3) pDNA can dissociate from polyplexes in reducing environments such as the cytoplasm. HABPs showed increased buffering capacity over histidine-ungrafted ABP, and HABPs formed nanosized polyplexes with pDNA. These polyplexes were about 90 nm in size and had positive charges of about of 30-40 mV. HABPs/pDNA polyplexes showed enhanced transfection efficiency and no significant cytotoxicity in comparison with polyethylenimine 25 kDa (PEI 25k), histidine-ungrafted ABP, and Lipofectamine (commercial reagent) in human cervical carcinoma (HeLa), rat cardiomyocytes (H9C2), and colon carcinoma (CT26) cells.


Assuntos
Arginina/química , Histidina/química , Poliaminas/química , DNA/genética , Endossomos/metabolismo , Técnicas de Transferência de Genes , Células HeLa , Humanos , Tamanho da Partícula , Plasmídeos/genética , Transfecção/métodos
4.
J Mater Sci Mater Med ; 26(4): 172, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25804307

RESUMO

Chronic total occlusions (CTOs) are common in patients with peripheral arterial disease (PAD). This study aimed to examine the feasibility and reliability of a CTO induced by a thin biodegradable polymer (polyglycolic acid) coated copper stent in a porcine femoral artery. Novel thin biodegradable polymer coated copper stents (9 mm long) were crimped on an angioplasty balloon (4.5 mm diameter × 12 mm length) and inserted into the femoral artery. Histopathologic analysis was performed 35 days after stenting. In five of six stented femoral arteries, severe in-stent restenosis and total occlusion with collateral circulation were observed without adverse effects such as acute stent thrombosis, leg necrosis, or death at 5 weeks. Fibrous tissue deposition, small vascular channels, calcification, and inflammatory cells were observed in hematoxylin-eosin, Carstair's, and von Kossa tissue stains; these characteristics were similar to pathological findings associated with CTOs in humans. The neointima volume measured by micro-computed tomography was 93.9 ± 4.04 % in the stented femoral arteries. CTOs were reliably induced by novel thin biodegradable polymer coated copper stents in porcine femoral arteries. Successful induction of CTOs may provide a practical understanding of their formation and application of an interventional device for CTO treatment.


Assuntos
Implantes Absorvíveis , Cobre/química , Modelos Animais de Doenças , Oclusão de Enxerto Vascular/patologia , Ácido Poliglicólico/química , Stents , Animais , Prótese Vascular , Materiais Revestidos Biocompatíveis/química , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Oclusão de Enxerto Vascular/fisiopatologia , Suínos
5.
Int J Mol Sci ; 16(4): 7995-8007, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25867474

RESUMO

Recently, the number of patients infected by drug-resistant pathogenic microbes has increased remarkably worldwide, and a number of studies have reported new antibiotics from natural sources. Among them, chitosan, with a high molecular weight and α-conformation, exhibits potent antimicrobial activity, but useful applications as an antibiotic are limited by its cytotoxicity and insolubility at physiological pH. In the present study, the antibacterial activity of low molecular weight water-soluble (LMWS) α-chitosan (α1k, α5k, and α10k with molecular masses of 1, 5, and 10 kDa, respectively) and ß-chitosan (ß1k, ß5k, and ß10k) was compared using a range of pathogenic bacteria containing drug-resistant bacteria isolated from patients at different pH. Interestingly, ß5k and ß10k exhibited potent antibacterial activity, even at pH 7.4, whereas only α10k was effective at pH 7.4. The active target of ß-chitosan is the bacterial membrane, where the leakage of calcein is induced in artificial PE/PG vesicles, bacterial mimetic membrane. Moreover, scanning electron microscopy showed that they caused significant morphological changes on the bacterial surfaces. An in vivo study utilizing a bacteria-infected mouse model found that LMWS ß-chitosan could be used as a candidate in anti-infective or wound healing therapeutic applications.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Água/química , Animais , Camundongos , Camundongos Endogâmicos ICR , Peso Molecular
6.
Environ Technol ; 36(1-4): 208-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25413115

RESUMO

Complete oxidation of volatile organic compound (toluene) was carried out to assess the property and activity of the palladium-spent iron based catalyst. The properties of the prepared catalysts were characterized by using the Brunauer-Emmett-Teller method and by conducting temperature-programmed reduction, X-ray diffraction, X-ray photoelectron spectroscopy and field emission transmission electron microscopy. The addition of palladium to the spent iron based catalyst pretreated with oxalic acid shifted the conversion curve for the total oxidation of toluene to lower temperature. An increase in the toluene conversion due to palladium was highly related to the easier lattice oxygen mobility of the catalysts. Instrumental analysis suggested the presence of a strong interaction between palladium and iron oxide species. Moreover, in the case of reducing the Pd/Fe catalyst with hydrogen, palladium accelerated the reducing iron oxides, subsequently decreasing the toluene conversion. As a result, the oxidation states of palladium and iron had an important effect on the catalytic activity.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Resíduos Industriais/prevenção & controle , Ferro/química , Paládio/química , Reciclagem/métodos , Tolueno/isolamento & purificação , Poluentes Atmosféricos/química , Catálise , Recuperação e Remediação Ambiental/métodos , Oxirredução , Tolueno/química
7.
Carbohydr Res ; 500: 108218, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33358143

RESUMO

Reactive oxygen species (ROS), induced by medical and life irradiation, have led to diverse diseases. Natural antioxidants (NAs) have been widely used to protect the body from the harmful effects of ROS. NAs have biocompatible properties but their bioavailability in the body is very low. This article discusses possible solutions to improve the bioavailability using several preparation and encapsulation techniques for microspheres using chitosan as a carrier. The first is the emulsion technique that controls particle size (0.5-1000 µm) according to the speed (RPM) of the agitator. The second technique discussed is spray drying-a very simple method that can control particle size (5-5000 µm) according to the nozzle size and discharge pressure. The third is the extrusion technique, which can control particle size (250-2500 µm) according to the syringe pore size. These techniques have enormous potential for use as drug delivery systems (DDS) in the functional food and biomedical field industries.


Assuntos
Antioxidantes/farmacocinética , Produtos Biológicos/farmacocinética , Quitosana/síntese química , Microesferas , Antioxidantes/química , Disponibilidade Biológica , Produtos Biológicos/química , Células CACO-2 , Configuração de Carboidratos , Quitosana/química , Humanos , Absorção Intestinal/efeitos dos fármacos
8.
Biotechnol Lett ; 32(1): 125-30, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19760117

RESUMO

A novel antifungal protein, M(r) = ca. 40 kDa, was isolated from pumpkin rind and designated Pr-1. When purified by anion exchange chromatography and HPLC, it inhibited growth of several fungi including Botrytis cinerea, Fusarium oxysporum, Fusarium solani and Rhizoctonia solani, as well as the yeast, Candida albicans, at 10-20 microM. It did not inhibit growth of Escherichia coli or Staphylococcus aureus even at 200 microM. Laser scanning microscopy of fungal cells exposed to rhodamine-labeled Pr-1 revealed that the protein accumulated and was localized on the cell surface. Uptake of the vital stain, SYTOX Green, was enhanced when fungal conidia were treated with Pr-1 suggesting that the protein has membrane permeabilization activity. Pr-1 was thermostable at 70 degrees C and did not lyse human red blood cells at 128 microM suggesting that the protein may be useful as an antifungal agent with little, if any human cytotoxicity.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Cucurbita/química , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Botrytis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Eritrócitos/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Temperatura Alta , Humanos , Testes de Sensibilidade Microbiana , Microscopia Confocal , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Estabilidade Proteica , Rhizoctonia/efeitos dos fármacos
9.
Pharm Res ; 26(9): 2152-63, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19557504

RESUMO

PURPOSE: A novel core-shell gene delivery system was fabricated in order to improve its gene transfection efficiency, particularly in the presence of serum. MATERIALS AND METHODS: alpha, beta-poly (L-aspartate-graft-PEI) (PAE) was simply synthesized by ring-opening reaction of poly (L-succinimide) with low molecular weight (LMW) linear polyethylenimine (PEI, Mn = 423). PAE/DNA nanoparticles were characterized. Condensation and protection ability of plasmid by PAE were confirmed by agarose gel electrophoresis assay. Cytotoxicity of the polymer and polymer/DNA nanoparticles were measured by MTS assay. Gene transfection efficiencies were evaluated both in vitro and in vivo. RESULTS: Core-shell nanoparticles assembled between DNA and PAE showed positive zeta potential, narrow size distribution, and spherical compact shapes with size below 250 nm when N/P ratio is above 10. Cytotoxicity of PAE was rather lower than that of PEI 25K, while the most efficient gene transfection and serum resistant ability of PAE/DNA complexes were higher than that of PEI 25K. Bafilomycin A1 treatment suggested "proton sponge" mechanism of PAE-mediated gene transfection. PAE/pEGFP-N2 nanoparticles also showed good gene expression in vivo and were dominantly distributed in kidney, liver, spleen and lung after intravenous administration. CONCLUSIONS: The results demonstrated the potential use of PAE as an effective gene carrier.


Assuntos
Ácido Aspártico/química , Técnicas de Transferência de Genes , Polietilenoimina/química , Cátions , Linhagem Celular , Eletroforese em Gel de Ágar , Humanos , Peso Molecular , Nanopartículas
10.
J Pept Sci ; 15(9): 589-94, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19642077

RESUMO

In this study, a HPA3NT3-analog (FKKLKKLFKKILKLK-NH2) peptide was designed. In this analog, two Trp residues (positions 12, 14) were replaced with Leu, and Arg and Asn (positions 3, 13) were replaced with Lys to investigate the role of amino acid substitution and increased cationicity on antimicrobial and hemolytic activities. In fungal and Gram-negative bacterial cells, HPA3NT3-analog activity was unchanged or slightly enhanced when compared to the HPA3NT3 peptide. In addition, a twofold decrease in activity against Gram-positive bacteria was observed. The HPA3NT3-analog also induced less hemolysis (4.2%) than the HPA3NT3 peptide (71%) at 200 microM. Circular dichroism (CD) spectra revealed that the HPA3NT3-analog peptide had an unordered structure in buffer and egg yolk L-2-phosphatidyl choline (EYPC), but adapted an alpha-helical conformation in 50% 2,2,2-trifluoroethanol (TFE) and negatively charged egg yolk L-2-phosphatidyl glycerol (EYPG), while the parent peptide showed an ordered structure in the EYPC. Additionally, the HPA3NT3-analog peptide induced the leakage of calcein from egg yolk L-2-phosphatidyl ethanolamine (EYPE)/EYPG (7:3 w/w) large unilamellar vesicles (LUVs); however, the activity was slightly weaker than that of the HPA3NT3 peptide. The molecular dynamics (MD) structures revealed that the amino acid substitutions induced a significant variation in peptide structure. These results suggest that the substitutions of Arg and Asn with Lys and two Trp with Leu resulted in small changes in HPA3NT3-analog activity and significant decreases in hemolytic activity.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Leucina/química , Lisina/química , Trichosporon/efeitos dos fármacos , Substituição de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/química , Dicroísmo Circular , Simulação por Computador , Fluoresceínas/química , Hemólise/efeitos dos fármacos , Humanos , Lipossomos/química , Testes de Sensibilidade Microbiana , Modelos Moleculares , Relação Estrutura-Atividade
11.
Int J Pharm ; 365(1-2): 150-6, 2009 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-18786625

RESUMO

The multiblock copolymer composed of poly(gamma-benzyl L-glutamate) (PBLG) and poly(ethylene oxide) (PEO) was synthesized to prepare polymeric micelles as an anticancer drug carrier. Adriamycin (ADR) used as an anticancer drug was incorporated into the polymeric micelles prepared by the multiblock copolymer. The higher the drug feeding ratio, the higher the drug loading contents and the lower the drug loading efficiency. The increased drug feeding ratio resulted in increased particle sizes. At all of the formulations, particle sizes were less than 150 nm. The particles were observed as spherical shapes. ADR release from ADR-loaded polymeric micelles in vitro was decreased with an increased drug loading contents. In in vitro antitumor activity test using CT 26 tumor cells, polymeric micelles showed almost similar cytotoxicity when compared to ADR itself while polymeric micelles themselves did not affect cytotoxicity. In in vivo antitumor activity test using mice tumor xenograft model, the polymeric micelles showed improved survivability of mice with minimized weight changes and excellent tumor growth suppression efficacy. Polymeric micelles of the multiblock copolymer suggested to be a good candidate for anticancer drug delivery carrier.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Polietilenoglicóis/química , Ácido Poliglutâmico/análogos & derivados , Animais , Antibióticos Antineoplásicos/administração & dosagem , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Doxorrubicina/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Micelas , Tamanho da Partícula , Ácido Poliglutâmico/química , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Mater Sci Mater Med ; 20(12): 2501-10, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19597971

RESUMO

The aim of the research is to study the effect of polyethylenimine (PEI) molecular weight on the gene transfection efficiency of degradable poly(amino ester) based on poly(ethylene glycol) dimethacrylate (PEGDMA) and polyethylenimine (PEG-cr-PEI) as a gene carrier. Various low molecular weight (LMW) branched PEI based PEG-cr-PEI was synthesized via Michael addition. The degradation half-life of PEG-cr-PEI was longer at pH 5.6 than that at pH 7.4. The plasmid condensation and protection ability of the PEG-cr-PEI were confirmed by agarose gel electrophoresis assay. PEG-cr-PEI/DNA nanoparticles showed high positive zeta potential (>+20 mV), narrow size distribution, and spherical shapes with size below 250 nm when N/P ratios of PEG-cr-PEI to DNA were above 10, suggesting that they have endocytosis potential. The cytotoxicity of PEG-cr-PEI/DNA complexes was lower than that of PEI 25K/DNA complexes, and the transfections mediated by PEG-cr-PEI were checked in 293T, HeLa and HepG2 cell lines. The report gene expression was increased with increasing the molecular weight of LMW PEI. The "proton sponge effect" was proposed as the mechanism of PEG-cr-PEI mediated gene transfection.


Assuntos
Vetores Genéticos , Metacrilatos/química , Poliaminas/química , Polietilenoglicóis/química , Polietilenoimina/química , Transfecção , Linhagem Celular , Eletroforese em Gel de Ágar , Ésteres , Humanos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Espectrofotometria Ultravioleta
13.
Int J Mol Sci ; 10(6): 2860-2872, 2009 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-19582234

RESUMO

Antimicrobial proteins (peptides) are known to play important roles in the innate host defense mechanisms of most living organisms, including plants, insects, amphibians and mammals. They are also known to possess potent antibiotic activity against bacteria, fungi, and even certain viruses. Recently, the rapid emergence of microbial pathogens that are resistant to currently available antibiotics has triggered considerable interest in the isolation and investigation of the mode of action of antimicrobial proteins (peptides). Plants produce a variety of proteins (peptides) that are involved in the defense against pathogens and invading organisms, including ribosome-inactivating proteins, lectins, protease inhibitors and antifungal peptides (proteins). Specially, the protease inhibitors can inhibit aspartic, serine and cysteine proteinases. Increased levels of trypsin and chymotrypsin inhibitors correlated with the plants resistance to the pathogen. Usually, the purification of antimicrobial proteins (peptides) with protease inhibitor activity was accomplished by salt-extraction, ultrafiltration and C(18) reverse phase chromatography, successfully. We discuss the relation between antimicrobial and anti-protease activity in this review. Protease inhibitors from plants potently inhibited the growth of a variety of pathogenic bacterial and fungal strains and are therefore excellent candidates for use as the lead compounds for the development of novel antimicrobial agents.


Assuntos
Anti-Infecciosos/metabolismo , Plantas/metabolismo , Inibidores de Proteases/metabolismo , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Fabaceae/metabolismo , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Peptídeos/farmacologia , Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/farmacologia , Solanum tuberosum/metabolismo
14.
Carbohydr Polym ; 209: 161-171, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30732795

RESUMO

To develop a carrier for targeted drug delivery and triggered drug release in a reducing-tumor environment, reduction-sensitive hyaluronic acid-g-stearic acid (HCS) micelles were synthesized using a coupling agent. The HCS 40% was shown to have a more compact particle size than HCS 20% and the particle size of doxorubicin (DOX)-loaded HCS (HCSD) was increased relative to that of HCS micelles. The behavior of DOX release from HCSD showed that DOX was rapidly released in GSH (10 mM) solution. The site-specific targeting effect of HCSD nanoparticles was investigated by cellular uptake and competition assay at HCT116 and CT26 cell lines. An in vivo study of HCSD revealed that tumor suppression and site-specific targeted delivery of HCSD nanoparticles in HCT116-xenografted tumors were more superb than in the CT26-xenografted tumor. These results suggest that HCSD nanoparticles can be expected to have high therapeutic efficacy because they enable targeted drug delivery and rapid drug release.


Assuntos
Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Ácido Hialurônico/química , Micelas , Ácidos Esteáricos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Glutationa/química , Células HCT116 , Humanos , Camundongos , Nanopartículas/química , Oxirredução
15.
Int J Biol Macromol ; 121: 301-308, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30312696

RESUMO

This study demonstrated the anti-adhesion and wound healing effect of a visible light curable anti-adhesion agent using an alginate derivative modified with a furfuryl moiety. Visible light-curable furfuryl alginate (F-Alg) was prepared in conjugation with alginate and furfurylamine by an amide coupling reaction, and the conjugated F-Alg was characterized by 1H NMR analysis. The cytotoxicity, cell adhesion, and cell permeability of the F-Alg were evaluated for use in anti-adhesion applications. Drug immobilization and protein release were assessed to verify whether the alginate derivatives and drugs were photo-immobilized. In in vivo anti-adhesion testing, the new anti-adhesion agent prepared in this study acted as a physical protective layer by forming a biofilm on the surgical site. Additionally, along with gradual decomposition of the photo-crosslinked alginate derivative, the immobilized drug was released, and additional effects such as accelerated wound healing are expected. Thus, visible light-curable F-Alg has good application potential as an anti-adhesion agent.


Assuntos
Alginatos/química , Alginatos/farmacologia , Furanos/química , Luz , Animais , Bovinos , Adesão Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Camundongos , Células NIH 3T3 , Soroalbumina Bovina/química , Cicatrização/efeitos dos fármacos
16.
J Gene Med ; 10(11): 1223-35, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18773499

RESUMO

BACKGROUND: Polyethylenimine (PEI) vectors are widely used in gene delivery because of their high transfection efficiency owing to a unique proton sponge effect. An increase in molecular weight increases transfection efficiency, but simultaneously results in increased toxicity. Therefore, the design and synthesis of new degradable gene delivery carriers having high transfection efficiencies and reduced cytotoxicity are necessary. METHODS: In the present study degradable poly(ester amines) (PEAs) based on glycerol dimethacrylate (GDM) and low molecular weight branched polyethylenimine (LMW-PEI) were synthesized in anhydrous methanol at 60 degrees C following Michael addition reaction. The transfection efficiencies of the synthesized PEA/DNA complexes were evaluated using three different cell lines (HeLa, HepG2 and 293T cells) in vitro. RESULTS: PEAs with zeta potential in the range of 30-55 mV (at physiological pH) condensed plasmid DNA into nanosized particles (<150 nm) suitable for intracellular delivery. The PEAs degraded in a controlled fashion (t(1/2) of approximately 9-10 days). Compared with PEI 25K, the PEAs showed significantly lower cytotoxicity in three different cells. The PEAs demonstrated much higher transfection efficiency compared to conventional PEI 25K and Lipofectamine. The PEA synthesized using a 1 : 4 mole ratio of GDM to PEI [GDM/PEI-1.2 (1:4)] showed the highest transfection efficiency in HepG2 cells. Significantly higher pEGFP-N(2) reporter gene expression in 293T cells was achieved using these PEAs. The hyperosmotic effect of PEAs was demonstrated by the reduction in packed cell volume (PCV). The GDM/PEI-1.2 (1:4) showed comparable reduction in PCV with respect to glycerol in 293T cells. The effect of bafilomycin A(1) on transfection efficiency of PEAs on 293T cells indicated its endosomal buffering capacity. CONCLUSIONS: We hypothesized that the higher transfection efficiency of PEAs was the synergistic effect arising from hyperosmotic glycerol and endosomal buffering capacity of PEAs resulting from the presence of a glycerol backbone and PEI amine groups, respectively.


Assuntos
Glicerol/química , Metacrilatos/química , Polietilenoimina/química , Transfecção , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Linhagem Celular , DNA/genética , DNA/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Técnicas de Transferência de Genes , Células HeLa , Humanos , Macrolídeos/farmacologia , Microscopia Confocal , Peso Molecular , Poliaminas/química , Poliaminas/metabolismo , Poliésteres/química , Poliésteres/metabolismo
17.
Int J Pharm ; 352(1-2): 317-23, 2008 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-18160236

RESUMO

The aim of this study was to prepare ciprofloxacin HCl (CIP)-encapsulated poly(dl-lactide-co-glycolide) (PLGA) copolymer nanoparticles and its antibacterial potential was evaluated with pathogenic bacteria, Escherichia coli (E. coli), in vitro and in vivo. CIP-encapsulated nanoparticles of PLGA were prepared by multiple emulsion solvent evaporation method. PLGA nanoparticles showed spherical shapes with particle sizes around 100-300 nm. Loading efficiency was lower than 50% (w/w) because of water-solubility properties of CIP. At drug release study, CIP showed initial burst effect for 12 h and then continuously released for 2 weeks. At in vitro antibacterial activity test, CIP-encapsulated nanoparticles showed relatively lower antibacterial activity compared to free CIP due to the sustained release characteristics of nanoparticles. However, CIP-encapsulated PLGA nanoparticles (doses: 25 mg CIP/kg of mice) effectively inhibited the growth of bacteria due to the sustained release characteristics of nanoparticles, while free CIP was less effective on the inhibition of bacterial growth. These results indicated that CIP-encapsulated PLGA nanoparticles have superior effectiveness to inhibit the growth of bacteria in vivo.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , Portadores de Fármacos , Ácido Láctico/química , Nanopartículas , Ácido Poliglicólico/química , Animais , Antibacterianos/química , Química Farmacêutica , Ciprofloxacina/química , Preparações de Ação Retardada , Composição de Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Cinética , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Solubilidade , Tecnologia Farmacêutica/métodos
18.
J Microbiol Biotechnol ; 18(10): 1729-34, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18955827

RESUMO

Chitosan, a cationic polysaccharide, has been widely used as a dietary supplement and in a variety of pharmacological and biomedical applications. The antifungal activity and mechanism of action of low molecular weight water-soluble chitosan (LMWS-chitosan) were studied in fungal cells and vesicles containing various compositions of fungal lipids. LMWS-chitosan showed strong antifungal activity against various pathogenic yeasts and hyphae-forming fungi but no hemolytic activity or cytotoxicity against mammalian cells. The degree of calcein leakage was assessed on the basis of lipid composition (PC/CH; 10:1, w/w). Our result showing that LMWS-chitosan interacts with liposomes demonstrated that chitosan induces leakage from zwitterionic lipid vesicles. Confocal microscopy revealed that LMWS-chitosan was located in the plasma membrane. Finally, scanning electron microscopy revealed that LMWS-chitosan causes significant morphological changes on fungal surfaces. Its potent antibiotic activity suggests that LMWS-chitosan is an excellent candidate as a lead compound for the development of novel anti-infective agents.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Quitosana/química , Quitosana/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Fungos/citologia , Fungos/efeitos dos fármacos , Hemolíticos/química , Hemolíticos/farmacologia , Humanos , Peso Molecular
19.
Int J Biol Macromol ; 115: 459-468, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29680502

RESUMO

Branched polyethylenimine (bPEI) was well known as high transfection agent, which has many amine group. However, utilization of bPEI was limited due to high toxicity. To solve these problems, bPEI was introduced to low molecular weight water-soluble chitosan (LMWSC) with coupling agent. In addition, hyaluronic acid (HA), one of natural anion polymer, was introduced to binary complex of pDNA/bPEI-grafted LMWSC (LMPEI) to target the specific cancer cell and impart the serum resistant. Ternary complexes of pDNA/LMPEI/HA were prepared by electrostatic charge interaction and their binding affinity and DNase protection assay were conducted by gel retardation assay. Particle size of ternary complexes showed that had each 482 ±â€¯245.4 (pDNA/LMPEI2%/HA, 1:16:1, w/w/w) and 410 ±â€¯78.5 nm (pDNA/LMPEI4%/HA, 1:16:2, w/w/w). Moreover, to demonstrate serum-resistant effect of ternary complexes, particle size of them was measured according to incubated time (0-10 h) under serum condition. Transfection assay of ternary complexes showed that their transfection efficiency in CD44-receptor overexpressed HCT116 cell was higher than CD44-receptor negative CT26 cell. Additionally, intracellular uptake of ternary complexes with propidium iodide (PI)-labeled pDNA was observed to confirm targeting effect and cellular internalization by fluorescence microscopy. These results suggest that ternary complexes are superb gene carrier with excellent serum-resistant and high gene transfection.


Assuntos
Portadores de Fármacos/química , Técnicas de Transferência de Genes , Ácido Hialurônico/química , Soro/metabolismo , Quitosana/química , Células HCT116 , Células HEK293 , Humanos , Espaço Intracelular/metabolismo , Tamanho da Partícula , Plasmídeos/genética , Polietilenoimina/química , Solubilidade , Água/química
20.
J Pharm Sci ; 107(10): 2702-2712, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29936202

RESUMO

Redox-responsive nanoparticles having a diselenide linkage were synthesized to target pulmonary metastasis of cancer cells. Methoxy poly(ethylene glycol)-grafted chitosan (ChitoPEG) was crosslinked using selenocystine-acetyl histidine (Ac-histidine) conjugates (ChitoPEGse) for stimuli-responsive delivery of piperlongumine (PL). ChitoPEGse nanoparticles swelled in an acidic environment and became partially disintegrated in the presence of H2O2, resulting in an increase of particle size and in a size distribution having multimodal pattern. PL release increased under acidic conditions and in the presence of H2O2. Uptake of ChitoPEGse nanoparticles by CT26 cells significantly increased in acidic and redox state. PL-incorporated ChitoPEGse nanoparticles (PL NPs) showed similar anticancer activity in vitro against A549 and CT26 cells compared to PL itself. PL NP showed superior anticancer and antimetastatic activity in an in vivo CT26 cell pulmonary metastasis mouse model. Furthermore, an immunofluorescence imaging study demonstrated that PL NP conjugates were specifically delivered to the tumor mass in the lung. Conclusively, ChitoPEGse nanoparticles were able to be delivered to cancer cells with an acidic- or redox state-sensitive manner and then efficiently targeted pulmonary metastasis of cancer cells since ChitoPEGse nanoparticles have dual pH- and redox-responsiveness.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Dioxolanos/química , Dioxolanos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/administração & dosagem , Nanopartículas/química , Células A549 , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quitosana/análogos & derivados , Quitosana/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Oxirredução , Polietilenoglicóis/química
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