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1.
Scand J Gastroenterol ; 59(9): 1112-1119, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39054602

RESUMO

AIM: To evaluate the effect of sodium picosulfate/magnesium citrate (SPMC) and 3 L split-dose polyethylene glycol (PEG) with or without dimethicone on bowel preparation before colonoscopy. METHODS: In this multicenter, prospective, randomized, controlled study conducted from April 2021 to December 2021, consecutive adult patients scheduled for colonoscopy were prospectively randomized into four groups: SPMC, SPMC plus dimethicone, 3 L PEG, and 3 L PEG plus dimethicone. Primary endpoint was colon cleansing based on Boston Bowel Preparation Scale (BBPS). Secondary endpoints were bubble score, time to cecal intubation, adenoma detection rate (ADR), patient safety and compliance, and adverse events. RESULTS: We enrolled 223 and 291 patients in SPMC and 3 L PEG group, respectively. The proportion with acceptable bowel cleansing, total BBPS score and cecal intubation time were similar in all four subgroups (p > 0.05). Patient-reported acceptability and tolerability was significantly greater in SPMC than 3 L PEG group (p < 0.001); adverse events were significantly lower in SPMC than latter group (p < 0.001). ADR in both groups was greater than 30%. CONCLUSION: SPMC had significantly higher acceptability and tolerability than 3 L PEG, however, was similar in terms of bowel-cleansing effect and cecal intubation time and hence can be used before colonoscopy preparation.


Assuntos
Catárticos , Citratos , Colonoscopia , Compostos Organometálicos , Picolinas , Polietilenoglicóis , Humanos , Colonoscopia/métodos , Feminino , Masculino , Catárticos/administração & dosagem , Catárticos/efeitos adversos , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , China , Estudos Prospectivos , Adulto , Citratos/administração & dosagem , Citratos/efeitos adversos , Picolinas/administração & dosagem , Picolinas/efeitos adversos , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/efeitos adversos , Idoso , Ácido Cítrico/administração & dosagem , Ácido Cítrico/efeitos adversos , Adenoma/diagnóstico , Cooperação do Paciente/estatística & dados numéricos
2.
J Assist Reprod Genet ; 41(5): 1245-1259, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38470552

RESUMO

BACKGROUND: Preimplantation genetic testing for monogenic disorders (PGT-M) is now widely used as an effective strategy to prevent various monogenic or chromosomal diseases. MATERIAL AND METHODS: In this retrospective study, couples with a family history of hereditary neurological diseases or metabolic diseases dominated by nervous system phenotypes and/or carrying the pathogenic genes underwent PGT-M to prevent children from inheriting disease-causing gene mutations from their parents and developing known genetic diseases. After PGT-M, unaffected (i.e., normal) embryos after genetic detection were transferred into the uterus of their corresponding mothers. RESULTS: A total of 43 carrier couples with the following hereditary neurological diseases or metabolic diseases dominated by nervous system phenotypes underwent PGT-M: Duchenne muscular dystrophy (13 families); methylmalonic acidemia (7 families); spinal muscular atrophy (5 families); infantile neuroaxonal dystrophy and intellectual developmental disorder (3 families each); Cockayne syndrome (2 families); Menkes disease, spinocerebellar ataxia, glycine encephalopathy with epilepsy, Charcot-Marie-Tooth disease, mucopolysaccharidosis, Aicardi-Goutieres syndrome, adrenoleukodystrophy, phenylketonuria, amyotrophic lateral sclerosis, and Dravet syndrome (1 family each). After 53 PGT-M cycles, the final transferable embryo rate was 12.45%, the clinical pregnancy rate was 74.19%, and the live birth rate was 89.47%; a total of 18 unaffected (i.e., healthy) children were born to these families. CONCLUSIONS: This study highlights the importance of PGT-M in preventing children born with hereditary neurological diseases or metabolic diseases dominated by nervous system phenotypes.


Assuntos
Testes Genéticos , Doenças Metabólicas , Diagnóstico Pré-Implantação , Humanos , Diagnóstico Pré-Implantação/métodos , Feminino , Gravidez , Testes Genéticos/métodos , Doenças Metabólicas/genética , Doenças Metabólicas/patologia , Estudos Retrospectivos , Masculino , Doenças do Sistema Nervoso/genética , Fenótipo , Adulto , Criança , Transferência Embrionária , Mutação/genética
3.
Pharm Res ; 37(12): 242, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188481

RESUMO

PURPOSE: In order to improve the therapeutic efficiency of the chemotherapeutic drug paclitaxel in tumors, a folate-based Paclitaxel nanoemulsion (FNEs) was developed for tumor targeted treatment. METHODS: In this study, we designed a folate-targeted nanoemulsion (folate/PEG-DSPE/nanoemulsion, FNEs) based on the traditional nanoemulsion using the principle of long-circulation targeting receptor mediated. The nanoemulsion (folate/PEG-DSPE/nanoemulsion, FNEs) was fabricated using high-pressure homogenization with a microfluidizer. RESULTS: The nanoemulsion (folate/PEG-DSPE/nanoemulsion, FNEs) can improve the delivery efficiency of nanocarriers at the tumor site by virtue of the high expression of folate receptors on the tumor surface. Malvern Nanoseries device and transmission electron microscopy (TEM) analyses showed that the nanoemulsions were spherical with an average diameter of 140 nm. The nanoemulsions can effectively carry paclitaxel (PTX) with an encapsulation rate of about 95%. And in vitro experiments have shown that it can efficiently increase the uptake of PTX in 4 T1 breast cancer cells and FNEs had a targeting capability hundredfold higher than that of PTX-loaded nanoemulsions (PTX-NEs) without folate. In vivo experiments have shown that the pharmacokinetic parameters of FNEs were better than those of other PTX groups and FNEs can significantly enhance circulation time in the body of the subcutaneously implanted 4 T1 breast cancer in mice, increase the accumulation of chemotherapy drugs at tumor sites and effectively inhibit tumor growth with lower system toxicity. CONCLUSIONS: This study can effectively improve the therapeutic efficiency of chemotherapy drugs for tumors, and provide an useful reference for solving the problem of low efficacy of chemotherapy drugs in clinical treatment of tumors. Graphical Abstract Schematic representation of Folic acid/PEG-DSPE/nano-emulsion (FNEs) specifically target tumor cells and enhanced anti-tumor effects.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos , Ácido Fólico/metabolismo , Nanopartículas , Paclitaxel/administração & dosagem , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Composição de Medicamentos , Emulsões , Feminino , Ácido Fólico/química , Transportadores de Ácido Fólico/metabolismo , Injeções Intravenosas , Camundongos , Camundongos Endogâmicos BALB C , Nanotecnologia , Paclitaxel/química , Paclitaxel/farmacocinética , Ratos Sprague-Dawley , Carga Tumoral/efeitos dos fármacos
4.
Mol Pharm ; 16(6): 2648-2660, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31046290

RESUMO

The complement system plays an important role in host innate immunity, and its activation can be exploited as a potential strategy for vaccine adjuvants. Herein, a pH-responsive micellar vaccine platform (COOH-NPs) was developed using a carboxyl-modified diblock copolymer of poly(2-ethyl-2-oxazoline)-poly(d,l-lactide) (COOH-PEOz-PLA). The copolymer self-assembled into micelles with hydroxyl groups shielding on the surface, which activated the complement system for the enhanced immune responses. Compared with the control nanoparticles (OCH3-NPs), COOH-NPs significantly enhanced lymph node-resident dendritic cell maturation, antigen-specific IgG production, antigen-specific CD4+ and CD8+ T-cell activation, and the amount of memory T-cell generation in vivo. Furthermore, immunization with COOH-NPs/OVA in E.G7-OVA tumor-bearing mice not only remarkably inhibited tumor growth but also prolonged the survival of tumor-bearing mice. These results indicated that COOH-NPs with the capability of complement activation efficiently boosted the immune responses for the antitumor effect. The study demonstrated the significance of taking advantage of a complement-activating vaccine platform for cancer immunotherapy.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Polímeros/química , Animais , Células da Medula Óssea/metabolismo , Vacinas Anticâncer/imunologia , Ativação do Complemento/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Micelas , Nanopartículas/química
5.
Biomacromolecules ; 19(7): 2595-2609, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29618203

RESUMO

A multifunctional nanoparticulate system composed of methoxy poly(ethylene glycol)-poly(l-histidine)-d-α-vitamin E succinate (MPEG-PLH-VES) copolymers for encapsulation of doxorubicin (DOX) was elaborated with the aim of circumventing the multidrug resistance (MDR) in breast cancer treatment. The MPEG-PLH-VES nanoparticles (NPs) were subsequently functionalized with biotin motif for targeted drug delivery. The MPEG-PLH-VES copolymer exerts no obvious effect on the P-gp expression level of MCF-7/ADR but exhibited a significant influence on the loss of mitochondrial membrane potential, the reduction of intracellular ATP level, and the inhibition of P-gp ATPase activity of MCF-7/ADR cells. The constructed MPEG-PLH-VES NPs exhibited an acidic pH-induced increase on particle size in aqueous solution. The DOX-encapsulated MPEG-PLH-VES/biotin-PEG-VES (MPEG-PLH-VES/B) NPs were characterized to possess high drug encapsulation efficiency of approximate 90%, an average particle size of approximately 130 nm, and a pH-responsive drug release profile in acidic milieu. Confocal laser scanning microscopy (CLSM) investigations revealed that the DOX-loaded NPs resulted in an effective delivery of DOX into MCF-/ADR cells and a notable carrier-facilitated escape from endolysosomal entrapment. Pertaining to the in vitro cytotoxicity evaluation, the DOX-loaded MPEG-PLH-VES/B NPs resulted in more pronounced cytotoxicity to MCF-/ADR cells compared with DOX-loaded MPEG-PLH-VES NPs and free DOX solution. In vivo imaging study in MCF-7/ADR tumor-engrafted mice exhibited that the MPEG-PLH-VES/B NPs accumulated at the tumor site more effectively than MPEG-PLH-VES NPs due to the biotin-mediated active targeting effect. In accordance with the in vitro results, DOX-loaded MPEG-PLH-VES/B NPs showed the strongest inhibitory effect against the MCF-7/ADR xenografted tumors with negligible systemic toxicity, as evidenced by the histological analysis and change of body weight. The multifunctional MPEG-PLH-VES/B nanoparticulate system has been demonstrated to provide a promising strategy for efficient delivery of DOX into MCF-7/ADR cancerous cells and reversing MDR.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Nanopartículas/química , Animais , Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Endossomos/metabolismo , Feminino , Histidina/química , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/metabolismo , Polietilenoglicóis/química , alfa-Tocoferol/química
6.
Nanomedicine ; 13(7): 2189-2198, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28579434

RESUMO

Partly PEGylated polyamidoamine (PAMAM) dendrimer was used as the nanocarrier for the cytoplasmic delivery of kartogenin (KGN) to induce chondrogenic differentiation of mesenchymal stem cells (MSCs). Here, KGN was conjugated to the surface of PAMAM and the end group of polyethylene glycol (PEG) to obtain PEG-PAMAM-KGN (PPK) and KGN-PEG-PAMAM (KPP) conjugate, respectively. The effects of PPK and KPP on the in vitro chondrogenic differentiation of MSCs were evaluated. KPP induced higher expression of chondrogenic markers than PPK and free KGN. In particular, after treatment of KPP, CBF ß nuclear localization intensity was significantly increased, indicating enhanced efficacy of chondrogenesis. The fluorescein labeled PEG-PAMAM was capable to persist in the joint cavity for a prolonged time of both healthy and osteoarthritis (OA) rats. Thus, PEG-PAMAM could be a useful nanocarrier for intra-articular (IA) delivery of drug to treat OA.


Assuntos
Anilidas/administração & dosagem , Condrogênese/efeitos dos fármacos , Dendrímeros/química , Portadores de Fármacos/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Ácidos Ftálicos/administração & dosagem , Polietilenoglicóis/química , Anilidas/farmacocinética , Anilidas/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células-Tronco Mesenquimais/citologia , Osteoartrite/tratamento farmacológico , Ácidos Ftálicos/farmacocinética , Ácidos Ftálicos/farmacologia , Ratos
7.
Yao Xue Xue Bao ; 51(3): 356-61, 2016 03.
Artigo em Zh | MEDLINE | ID: mdl-29858892

RESUMO

Liposomes as a drug carrier is easy to form aggregation and cause drug leakage in vitro. In addition, the degradation and elimination in vivo happens frequently to reduce its delivery activity. Development and application of liposomes are restricted by the instability. The appropriate techniques and methods are great important in the study of pharmaceutical stability of liposomes. In this paper, the techniques and methods are reviewed on pharmaceutical stability evaluation of liposomes, which was done from physical, chemical and biological stability for the difference in stability of liposomes. The research strategies for establishing the stability evaluation system and improving the value of liposomes have been discussed to make full therapeutic advantage of it.


Assuntos
Portadores de Fármacos/farmacologia , Estabilidade de Medicamentos , Lipossomos/farmacologia
8.
Yao Xue Xue Bao ; 50(4): 434-9, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26223124

RESUMO

Poly(ß-amino esters) (PBAE) are used for drug carrier and have many advantages, such as pH-sensitivity, low toxicity, structural diversity and the synthetic method of PBAE is easy. Therefore they are possessed broad application prospect in tumor-targeted drugs delivery systems. In this paper, the structural features and target drugs delivery property of PBAE are reviewed. The application forms of PBAE and different anti-cancer drugs loaded in the copolymer for tumor-targeted drugs delivery systems are introduced particularly.


Assuntos
Antineoplásicos/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ésteres/química , Neoplasias/tratamento farmacológico , Concentração de Íons de Hidrogênio , Polímeros
9.
Biomacromolecules ; 15(11): 4032-45, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25308242

RESUMO

Various poly(l-histidine) based amphiphilic copolymers have been developed for intracellular drug delivery due to the pH responsive properties and the escape from endolysosomal pathway. However, the pH induced reassembly of copolymer micelles and the assumed endolysosome membrane rupture during the copolymer facilitated endolysosomal escape have never been elucidated. To address these issues, a series of poly(ethylene glycol)-poly(d,l-lactide)-poly(l-histidine) (mPEG-PLA-PHis) with different degrees of polymerization of PLA and PHis block were synthesized. The self-assembly and reassembly behaviors of the copolymers were characterized using transmission electron microscopy (TEM), (1)H NMR, fluorescence probe technique, and dynamic light scattering (DLS). The copolymers self-assembled into micelles with PLA and unprotonated PHis blocks as hydrophobic core and PEG as hydrophilic shell at neutral pH. The changes in TEM images, (1)H NMR spectrum of PHis peak, pyrene fluorescene spectrum, and particle size as well as size distribution over the pH range from pH 8.5 to 4.5 suggest that the copolymer micelles reassembled into micelles with PLA as hydrophobic core and protonated PHis and PEG as hydrophilic shell under acidic environment. The pH induced reassembly triggered the incoporated doxorubicin (DOX) release, as indicated by the in vitro accelerated drug release and enhanced cytotoxicity. The integrity of endolysosome membrane during the copolymer facilitated DOX endolysosomal escape was observed by confocal laser scan microscopy (CLSM) and further evaluated by hemolysis test and calculation of the critical size of endolysosomal membrane. The results indicate that the endolysosomal membrane remained intact during the copolymer facilitated endolysosomal escape of DOX. It is more reasonable to ascribe the PHis based copolymer facilitation endolysosomal escape to the "proton sponge" hypothesis without rupturing the endolysosomal membrane.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Histidina/química , Líquido Intracelular/efeitos dos fármacos , Micelas , Polímeros/química , Animais , Histidina/administração & dosagem , Histidina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Líquido Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Células MCF-7 , Masculino , Polímeros/administração & dosagem , Polímeros/metabolismo , Ratos , Ratos Sprague-Dawley
10.
Pharm Res ; 31(12): 3289-303, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24858397

RESUMO

PURPOSE: Using different chain lengths of PEG as linkers to develop a novel folate (FA) and TAT peptide co-modified doxorubicin (DOX)-loaded liposome (FA/TAT-LP-DOX) and evaluate its potential for tumor targeted intracellular drug delivery. METHODS: FA/TAT-LP-DOX was prepared by pH gradient method and post-insertion method and the optimal ligand density was screened by MTT assay. In vitro evaluation was systematically performed through cytotoxicity assay, cellular uptake studies, subcellular localization and cellular uptake mechanism in folate receptor (FR) over-expressing KB tumor cells. In vivo tumor targeted delivery of FA/TAT-LP-DOX was also studied by in vivo fluorescence imaging in a murine KB xenograft model. RESULTS: The particle size and zeta potential determination indicated that FA and TAT were successfully inserted into the liposome and cationic TAT peptide was completely shielded. With the optimal ligand density (5% of FA and 2.5% TAT), the FA/TAT-LP-DOX exhibited improved cytotoxity and cellular uptake efficiency compared with its single-ligand counterparts (FA-LP-DOX and PEG/TAT-LP-DOX). Competitive inhibition and uptake mechanism experiments revealed that FA and TAT peptide played a synergistic effect in facilitating intracellular transport of the liposome, and association between FA and FA receptors activated this transport process. In vivo imaging further demonstrated the superiority of FA/TAT-LP in tumor targeting and accumulation. CONCLUSIONS: Folate and TAT peptide co-modified liposome using different chain lengths of PEG as linkers may provide a useful strategy for specific and efficient intracellular drug delivery.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Ácido Fólico/química , Produtos do Gene tat/química , Lipossomos/química , Lipossomos/farmacocinética , Peptídeos/química , Peptídeos/farmacocinética , Animais , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Células KB , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Polietilenoglicóis , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Adv Healthc Mater ; 13(20): e2400219, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38657266

RESUMO

The intricate tumor microenvironment in triple-negative breast cancer (TNBC) hampers chemotherapy and immunotherapy efficacy due to dense extracellular matrix (ECM) by tumor-associated fibroblasts (TAFs). Nanoparticle-based therapies, especially "all-in-one" nanoparticles, have shown great potential in combined drug delivery strategies to reshape the tumor microenvironment and enhance therapeutic efficiency. However, these "all-in-one" nanoparticles suffer from limitations in targeting different target cells, uncontrollable dosing ratio, and disregarding the impact of delivery schedules. This study prepared cell membrane fusion liposomes (TAFsomes and CCMsomes) to load FDA-approved antifibrotic drug pirfenidone (PFD/TAFsomes) and antitumor drug doxorubicin (DOX/CCMsomes). These liposomes can specifically target TAFs cells and tumor cells, and combined administration can effectively inhibit TAFs activity, reshape the tumor microenvironment (TME), and significantly enhance the tumor chemotherapy efficacy. Combined drug delivery defeats "all-in-one" liposomes (DOX/PFD/Liposomes, DOX/PFD/TAFsomes, and DOX/PFD/CCMsomes) by flexibly adjusting the drug delivery ratio. Moreover, an asynchronous delivery strategy that optimizes the administration schedule not only further improves the therapeutic effect, but also amplifies the effectiveness of α-PD-L1 immunotherapy by modulating the tumor immune microenvironment. This delivery strategy provides a personalized treatment approach with clinical translation potential, providing new ideas for enhancing the therapeutic effect against solid tumors such as TNBC.


Assuntos
Doxorrubicina , Lipossomos , Microambiente Tumoral , Lipossomos/química , Microambiente Tumoral/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/química , Doxorrubicina/administração & dosagem , Humanos , Linhagem Celular Tumoral , Animais , Feminino , Camundongos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Piridonas/química , Piridonas/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus
12.
Drug Dev Ind Pharm ; 39(5): 770-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22794139

RESUMO

In this work, solid lipid nanoparticles loaded with cucurbitacin B (Cu B-SLNs) were prepared. It was found that the concentration of poloxamer 188 and soybean lecithin had effects on the mean particle size and size distribution. The zeta potentials were around -33 mV. In vitro release studies showed a sustained release after a burst release. Internalization of Cu B into HepG2 cells could be enhanced by the encapsulation of SLN matrix. The IC50 values of Cu B-SLNs were lower than that of Cu B solution. Both free Cu B and Cu B-SLNs had effectively inhibited the tumor growth and displayed a dose-dependent anti-tumor efficacy. Cu B-SLNs at a dose of 0.11 mg/kg produced the greatest anti-tumor effects (53.3%), which was significant higher than Cu B solution (31.5%, p < 0.05). Cu B-SLNs showed a longer MRT in vivo. The AUC of Cu B-SLNs for tumor increased 3.5 -fold when compared to Cu B solution. The targeting efficiency of Cu B-SLNs was 1.94 times higher in liver as compared to that of Cu B solution. These results indicated that Cu-B SLNs could passively target the tumor with EPR effect, improve the therapeutic efficacy of Cu B, and reduce the doses.


Assuntos
Antineoplásicos/química , Portadores de Fármacos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Nanopartículas/química , Triterpenos/química , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Área Sob a Curva , Portadores de Fármacos/química , Células Hep G2/efeitos dos fármacos , Humanos , Lipídeos/química , Neoplasias Hepáticas Experimentais/metabolismo , Camundongos , Tamanho da Partícula , Poloxâmero/química , Triterpenos/farmacocinética , Triterpenos/farmacologia
13.
J Microencapsul ; 30(5): 432-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23517067

RESUMO

The aim of this study was to develop poly(D,L-lactide-co-glycolide)/montmorillonite (PLGA/MMT) nanoparticles formulations for improved oral delivery of exemestane. Exemestane-loaded PLGA nanoparticles and PLGA/MMT nanoparticles were prepared by a modified solvent extraction/evaporation technology with vitamin E succinated polyethylene glycol 1000 (TPGS) as emulsifier. The content of MMT was estimated by thermal gravimetric analysis. The drug encapsulation efficiency and in vitro drug release kinetics were measured by high-performance liquid chromatography. The size, size distribution, surface charge and morphology of the exemestane-loaded nanoparticles were characterized using a Zetasizer Nano ZS and field emission scanning electron microscopy. The physical status of exemestane in the nanoparticles was characterized by differential scanning calorimetry. In vitro cellular uptake of coumarin-6-loaded nanoparticles was investigated by confocal laser scanning microscope, demonstrating that the fluorescence nanoparticles were internalized by Caco-2 cells (as an in vitro gastrointestinal model). The results of in vitro cytotoxicity experiment on MCF-7 cells (as a model of breast cancer cells) showed the exemestane-loaded nanoparticles resulted in lower cell viability versus the pure exemestane solution. The cytotoxicity against MCF-7 cells for exemestane-loaded nanoparticles and pure exemestane solution was dependent on the drug concentration and incubation time. In conclusion, this study indicates the capability of PLGA nanoparticles and PLGA/MMT nanoparticles in enhancing the oral delivery of exemestane.


Assuntos
Androstadienos/administração & dosagem , Antineoplásicos/administração & dosagem , Bentonita/química , Portadores de Fármacos/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Androstadienos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Células CACO-2 , Linhagem Celular Tumoral , Feminino , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
14.
AAPS PharmSciTech ; 13(4): 1377-85, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23054989

RESUMO

The current study aims to develop a stable pH-sensitive drug delivery system. First, cleavable polyethylene glycol-α-tocopherol hemisuccinate (PEG-THS) was synthesized. Conventional pH-sensitive vesicles composed of the Tris salt of α-tocopherol hemisuccinate (THST) were then prepared using the detergent removal technique. The vesicles had a mean particle size of (163.8 ± 5.5) nm and a zeta potential of -74.5 ± 6.4 mV. The THST vesicles were then modified using PEG-THS or uncleavable PEG-cholesterol (PEG-CHOL) (THST/PEG-lipids, 100:6 molar ratio). The mean vesicle particle size and absolute zeta potential decreased with increasing PEG-THS proportion. When the pH was decreased, the vesicle particle size and calcein release rate increased. The THST vesicles were initially Ca(2+)-unstable but exhibited significantly improved stability after modification with PEG-THS, especially at PEG-lipid ratios above 6%. Incubation in an acid serum increased the calcein release rate of conventional THST vesicles to 45 ± 1.98% at 10 min. However, the release rate of the PEG-CHOL vesicles remained low. The calcein release rate of PEG-THS vesicles was between those of conventional and PEG-CHOL-V. Therefore, PEG-THS can protect vesicles in serum and reconstitute their pH sensitivity in acidic conditions. Cleavable PEG-THS can be used in stable pH-sensitive preparations without loss of pH sensitivity. Free calcein and conventional vesicles eliminated from the plasma soon after injection, as well as the half-life (t(1/2)) and area under the curve of PEG-THS-V encapsulating calcein, were dramatically increased. This phenomenon indicates that the use of PEG-lipid derivatives has gained a favorably long circulation effect in mice.


Assuntos
Polietilenoglicóis/química , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/química , Animais , Área Sob a Curva , Soluções Tampão , Cálcio/química , Colesterol/química , Sistemas de Liberação de Medicamentos/métodos , Estabilidade de Medicamentos , Fluoresceínas/química , Meia-Vida , Concentração de Íons de Hidrogênio , Lipídeos/química , Masculino , Camundongos , Tamanho da Partícula , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacocinética , Soro/química , Soluções/química , alfa-Tocoferol/farmacocinética
15.
ACS Appl Mater Interfaces ; 14(18): 20762-20777, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35476413

RESUMO

The tumor immunosuppressive microenvironment (TIM) greatly hindered the efficacy of cancer immunotherapy. Overexpressed indoleamine 2,3-dioxygenase-1 (IDO1) in tumor tissues plays a vital role in TIM generation, and downregulation of IDO1 expression may reverse TIM. Inspired by the Watson-Crick base-pairing rule, a versatile noncationic miRNA vector (miDAC@PDA) is developed for cancer immunotherapy. Doxorubicin (DOX), adenosine triphosphate (ATP), and copper ions (Cu2+) are coassembled into coordination polymer nanoparticles (DAC) and bind miRNA via the hydrogen bond interaction (miDAC) between adenine residues (ATP) and uracil residues (miRNA). Polydopamine (PDA) is deposited onto the surface of miDAC for photothermal therapy. miDAC@PDA can efficiently accumulate into tumor tissues for cellular uptake. Under laser irradiation and high intracellular GSH levels, the PDA shell of miDAC@PDA can dissociate from miDAC for miRNA release due to local hyperthermia. Cu2+-mediated GSH consumption and intracellular ATP release can amplify the DOX-based immunogenic cell death (ICD) cascade, together with miR-448-mediated IDO1 inhibition, and these versatile nanoplexes will not only restrain primary tumor growth but also display a remarkable abscopal effect on distant tumors. Collectively, our study provides a unique strategy for intracellular gene delivery and an inspirational approach for multimechanism cancer management.


Assuntos
Hipertermia Induzida , MicroRNAs , Nanopartículas , Neoplasias , Trifosfato de Adenosina , Animais , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Lasers , Camundongos , Nanopartículas/química , Neoplasias/terapia , Fototerapia , Polímeros/química , Microambiente Tumoral
16.
Chem Pharm Bull (Tokyo) ; 59(1): 63-71, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21212549

RESUMO

Recently, dendrimers have been widely used in medical applications such as drug delivery and gene transfection. In this study, a pH-sensitive diblock copolymer of poly(methacryloyl sulfadimethoxine) (PSD) and polyethylene glycol (PEG) modified by lactose (LA-PEG-b-PSD) was synthesized. The pK(a) value of the LA-PEG-b-PSD was also measured. Then, polyamidoamine (PAMAM) complexes were prepared with PAMAM (G4.0) and LA-PEG-b-PSD by electrostatic interaction. To investigate drug pH-sensitive release in vitro, doxorubicin (DOX) was loaded in PAMAM. A higher drug cumulative release from LA-PEG-b-PSD/PAMAM complexes in phosphate buffered saline (PBS) was found at pH 6.5 than at pH 7.4. The cytotoxicity and cellular uptake of PAMAM complexes were investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and confocal microscopy. LA-PEG-b-PSD/PAMAM/DOX complexes were able to enhance the cytotoxicity of DOX against HepG2 cells at pH 7.4. Confocal microscopy showed a higher cellular uptake of PEG-b-PSD/PAMAM complexes at pH 6.5. PAMAM complexes modified by lactose showed a higher affinity for hepatic cancer cells than those without lactose at pH 7.4. These results suggest that LA-PEG-b-PSD/PAMAM complexes exhibit selective targeting and cytotoxicity against HepG2 cells. In vivo antitumor studies showed that the LA-PEG-b-PSD/PAMAM/DOX complexes displayed higher antitumor efficacy compared with non-targeted PAMAM/DOX and DOX solution. These results indicate that this strategy should be applicable to the treatment of liver cancers.


Assuntos
Antineoplásicos/administração & dosagem , Dendrímeros/química , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Carcinoma Hepatocelular/tratamento farmacológico , Dendrímeros/toxicidade , Doxorrubicina/administração & dosagem , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Lactose/química , Neoplasias Hepáticas/tratamento farmacológico , Polietilenoglicóis/química , Sulfadimetoxina/química
17.
Chem Pharm Bull (Tokyo) ; 59(5): 618-23, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21532200

RESUMO

The conjugation of Ulex europaeus agglutinin I (UEAI) onto surface of liposomes has been demonstrated to effectively improve the intestinal absorption of antigen, subsequently induced strong mucosal and systemic immune responses. In this context, we prepared bovine serum albumin (BSA)-encapsulating UEAI-modified liposomes (UEAI-LIP) and unmodified ones (LIP). The specific bioadhesion on mice gastro-intestinal mucosa was studied ex vivo. An important increase of interaction between UEAI-conjugated liposomes and the intestinal segments with Peyer's Patches (PPs) was observed compared with the unconjugated one (p<0.01). However, under the presence of α-L-fucose, which is the reported specific sugar for UEAI, specifically inhibited the activity of these conjugates. The immune-stimulating activity in vivo was studied by measuring immunoglobulin G (IgG) levels in serum and immunoglobulin A (IgA) levels in intestinal mucosal secretions following oral administration of BSA solution, LIP and UEAI-LIP in mice. Results indicate that antigen encapsulated in liposomes, especially the UEAI-modified ones, was favorable for inducing immune response. At 42 d after the first immunization, the highest IgG and IgA antibody levels produced by UEAI-LIP occurred, respectively showing 4.4-fold and 5-fold higher levels compared to those of the groups receiving BSA alone. This data demonstrated high potential of UEAI-modified liposomes for their use as carrier for oral vaccines.


Assuntos
Imunização/métodos , Lipossomos/administração & dosagem , Lectinas de Plantas/administração & dosagem , Vacinação/métodos , Vacinas/administração & dosagem , Administração Oral , Animais , Adesão Celular/efeitos dos fármacos , Feminino , Imunidade nas Mucosas/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Lipossomos/imunologia , Lipossomos/farmacologia , Camundongos , Camundongos Endogâmicos , Lectinas de Plantas/imunologia , Lectinas de Plantas/farmacologia , Soroalbumina Bovina/administração & dosagem , Soroalbumina Bovina/imunologia , Soroalbumina Bovina/farmacologia , Vacinas/imunologia , Vacinas/farmacologia
18.
Yao Xue Xue Bao ; 46(2): 227-31, 2011 Feb.
Artigo em Zh | MEDLINE | ID: mdl-21542295

RESUMO

Rheological properties of poloxamer 407 (brand named Pluronic F127) were examined by changing shear rate, temperature and the recovery properties of apparent viscosity after heating for several times. The results indicated that poloxamer 407 aqueous solution showed a Newtonian behavior at a low concentration while it might be a pseudoplastic fluid when the concentration reached a certain point. The thixotropy and the sol-gel transition temperature decreased with increasing the concentration (it could be an in situ gel at body temperature when the concentration of poloxamer 407 up to 15.25%). The results that obtained from the theological data would be useful in the application of poloxamer 407 such as in situ gel preparation.


Assuntos
Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Excipientes/química , Poloxâmero/química , Relação Dose-Resposta a Droga , Excipientes/administração & dosagem , Poloxâmero/administração & dosagem , Reologia , Resistência ao Cisalhamento , Soluções , Temperatura , Viscosidade , Água
19.
Yao Xue Xue Bao ; 46(7): 839-44, 2011 Jul.
Artigo em Zh | MEDLINE | ID: mdl-22010355

RESUMO

The dialysis method was employed to prepare blank and doxorubicin (DOX) loaded micelles formed by temperature- and pH- sensitive polyhistidine-co-polyDL-lactide-co-glycolide-co-polyethyleneglycol-co-polyDL-lactide-co-glycolide-co-polyhistidine (PHis-b-PLGA-b-PEG-b-PLGA-b-PHis). The critical micelle concentrations (CMC) of the copolymers were measured with Pyrene Fluorescent Probe Technique. The temperature- and pH- sensitive properties of the blank micelles solution were investigated by optical transmittance measurement. The morphology and diameter of DOX micelles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The entrapment rate and drug-loading rate were determined with dialysis method. The in vitro release study was further performed to examine the temperature- and pH-responsive drug release behavior from DOX-loaded micelles. The results indicated that the CMC, entrapment efficiency and drug-loaded amount of the micelles were 7.5 x 10(-3) g x L(-1), 85.2 +/- 3.1% and 10.4 +/- 4.5%, respectively. The DOX micelle was globular-shaped with a mean diameter of 91.1 +/- 15.8 nm. The transmittance of micelle solution consistently increased with the increasing temperature or decreasing pH. In comparison to the drug release profile at physiological conditions (37 degrees C, pH 7.4), the DOX-loaded micelles showed faster drug release rate at higher temperature (41 degrees C), lower pH (pH 7.0, pH 6.5, pH 5.0) or higher temperature and lower pH (41 degrees C, pH 5.0). This indicated that the micelles showed a temperature and pH-triggered drug release pattern. Base on the above results, it can be concluded that PHis-b-PLGA-b-PEG-b-PLGA-b-PHis block copolymer micelles which respond to temperature and pH stimuli are promising smart carriers for anti-tumor drugs with the advantages of temperature- and pH- triggered drug release.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Histidina/química , Polietilenoglicóis/química , Poliglactina 910/química , Antibióticos Antineoplásicos/química , Doxorrubicina/química , Portadores de Fármacos , Composição de Medicamentos , Concentração de Íons de Hidrogênio , Micelas , Tamanho da Partícula , Polímeros/química , Temperatura
20.
J Diabetes Investig ; 12(11): 2099-2101, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33991180

RESUMO

Both diabetes mellitus and Charcot-Marie-Tooth disease (CMT) can lead to severe peripheral neuropathy. The differential diagnosis of peripheral neuropathy is difficult due to the similar clinical features. There are still some clues, such as unusual muscle atrophy, unmatched severity of peripheral neurogenic damage with nephropathy or retinopathy, which could alert clinicians to make differential diagnosis. Although diabetes mellitus is rarely concurrent with CMT, it will exacerbate clinical disorders in patients with CMT. To date, there is no specific medicine for CMT treatment. Offloading devices and desirable comprehensive management of diabetes mellitus might be beneficial to avoid plantar ulcer recurrence and anti-progression of CMT.


Assuntos
Doença de Charcot-Marie-Tooth/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/diagnóstico , Úlcera do Pé/diagnóstico , Adulto , Doença de Charcot-Marie-Tooth/complicações , Pé Diabético/etiologia , Diagnóstico Diferencial , Erros de Diagnóstico , Úlcera do Pé/etiologia , Humanos , Masculino , Ilustração Médica , Recidiva
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