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1.
Zhongguo Zhong Yao Za Zhi ; 47(16): 4462-4468, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36046876

RESUMO

An ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method was established for the determination of active components of Sarcandrae Herba, and applied to the pharmacokinetics study of multiple dosage forms. After SD rats were administered by gavage with three dosage forms [Sarcandrae Herba extract, commercial Sarcandrae Herba Guttate Pills, and polydopamine guttate pills loaded with active components of Sarcandrae Herba(PDA-Sg Guttate Pills)], blood samples were collected from the inner canthus at different time points. After protein precipitation, plasma samples were separated on ACQUITY UPLC C_(18) column(2.1 mm×100 mm, 1.7 µm). The mobile phase consisted of water containing 0.2% formic acid and acetonitrile in gradient elution. The negative ions were measured simultaneously in the multi-reaction monitoring(MRM) mode. The pharmacokinetic parameters were calculated and fitted by DAS 2.0. All four components could be detected in the plasma of rats in each group at each time point except the neochlorogenic acid and cryptochlorogenic acid in the Sarcandrae Herba extract group. The guttate pills group showed a significant increase in drug content at each time point. The exposure of the main components of Sarcandrae Herba in blood was effectively increased by PDA-drug loading effect in PDA-Sg Guttate Pills(The AUC_(0-24 h) of neochlorogenic acid, cryptochlorogenic acid, isaziridin and rosmarinic acid reached 2.45, 32.90, 1.54, 4.81 times that of the commercial guttate pills). This study proves the measurability of the above-mentioned multi-component in vitro-in vivo delivery process. The pharmacokinetic study has shown that PDA-Sg Guttate Pills can effectively delay the elimination time and improve the bioavailability of the four components, which can provide theoretical data for the production of the drug.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Indóis , Polímeros , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
2.
Pharm Dev Technol ; 25(7): 865-873, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32266855

RESUMO

Fenretinide (4-HPR), as a semi-synthetic retinoid, has apoptosis-promoting effects as a single agent and chemotherapy synergist in vitro. When a human ovarian cancer cells line (A2780s) was treated with both PTX and 4-HPR, there was a synergistic anti-cancer effect demonstrated with a average combination index of 0.44. In this research, a new TPGS-Soluplus® mixed micelles were developed which encapsulation efficiencies of paclitaxel (PTX) and fenretinide (4-HPR) were as high as 98%, and the average diameter of the micelles was 66.26 nm. Cytotoxicity of the mixed micelles co-delivered with PTX and 4-HPR reduced significantly 7.3 and 25.1 times compared with free drug respectively in A2780s cells. More importantly, in vivo pharmacokinetic study, the loaded drugs in mixed micelles exhibited higher AUC and t1/2 values than free drugs. Furthermore, in vivo antitumor efficacy experiments demonstrated that PF-TS exhibited superior in vivo antitumor activity on the inhibition rate of tumor growth than other treatment groups (77.8% corresponding tumor growth inhibition in PF-TS treated group vs 19.9, 12.5, and 26.0% of tumor growth inhibition rate in Taxol®, 4-HPR, and Taxol®+4-HPR, respectively). Therefore, the mixed micelles of co-deliver PTX and 4-HPR successfully constructed may hopefully be applied to the cancer combination treatment with less toxic effect and more antitumor activity.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Fenretinida/administração & dosagem , Micelas , Paclitaxel/administração & dosagem , Polietilenoglicóis/administração & dosagem , Polivinil/administração & dosagem , Vitamina E/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Feminino , Fenretinida/farmacocinética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Paclitaxel/farmacocinética , Polietilenoglicóis/farmacocinética , Polivinil/farmacocinética , Ratos , Ratos Wistar , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/fisiologia , Vitamina E/farmacocinética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
3.
Pharm Dev Technol ; 25(8): 962-970, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32366203

RESUMO

Fenretinide (4-HPR), a synthetic retinoid, has shown its antitumor activity in many tumor types with low cytotoxicity to normal cells and high clinical safety. However, the low water solubility limits its further biological applications. To increase solubility, 4-HPR was conjugated with methoxy polyethylene glycol carboxylic acid (mPEG2K-COOH) by an ester linkage between the phenol hydroxyl of 4-HPR and the carboxyl of mPEG2K-COOH. The 4-HPR-PEG2K conjugate micelles had mean size of 76.70 ± 1.248 nm with a narrow distribution and a low critical micelle concentration. In vitro cytotoxicity studies showed the micelles have higher cytotoxicity to A2780s and MCF-7 cells. Its IC50 was 4.7 and 4.1-fold lower than the free 4-HPR, respectively. Importantly, in vivo pharmacokinetic studies, the AUC of 4-HPR was found to be 2.3-fold higher in 4-HPR-PEG2K micelles compared to free 4-HPR. And the 4-HPR-PEG2K micelles had higher antitumor activity. Meanwhile, the histopathology analysis exhibited that the micellar treatment decreased the viability of A2780s cells and increased the level of induced apoptosis. Therefore, the enhanced activity of 4-HPR by the method of conjugation with mPEG2K-COOH could hopefully provide new insights into the matter of ovarian cancer and breast cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Fenretinida/farmacologia , Polietilenoglicóis/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Ratos Sprague-Dawley , Solubilidade/efeitos dos fármacos
4.
Pharm Dev Technol ; 25(1): 107-115, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31603017

RESUMO

In this study, mixed micelles of Soluplus® and TPGS were developed for co-administering docetaxel (DTX) and piperine (PIP) for exerting the synergistic effect, which increased the cytotoxicity and improved the anti-cancer activity in HepG2 cell lines compared to free DTX. These in vitro (MTT assay, intracellular uptake of micelles) and in vivo (pharmacokinetic study, immunostaining, TUNEL analysis) studies exhibited the advantages of co-delivery of anticancer drugs with Soluplus®/TPGS by mixed micelles and furthermore established that co-delivery of DTX and PIP via the mixed micelles of Soluplus®/TPGS could be a promising strategy for the treatment of liver cancer.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Benzodioxóis/química , Benzodioxóis/farmacologia , Docetaxel/química , Docetaxel/farmacologia , Neoplasias/tratamento farmacológico , Piperidinas/química , Piperidinas/farmacologia , Polietilenoglicóis/química , Alcamidas Poli-Insaturadas/química , Alcamidas Poli-Insaturadas/farmacologia , Polivinil/química , Vitamina E/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Células Hep G2 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Ratos , Ratos Sprague-Dawley
5.
Pharm Dev Technol ; 24(9): 1125-1132, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31305197

RESUMO

Clinically, co-delivery of chemotherapeutics has been limited by poor water-solubility and severe systemic toxicity. This study was aimed at integrating the merits of combination chemotherapy and mixed micellar technology and demonstrating the anticancer potential of doxorubicin (DOX) and dihydroartemisinin (DHA) co-loaded Soluplus®-TPGS mixed micellar system. In this study, physiochemically stable multidrug loaded mixed micelles were successfully prepared, encapsulation efficiencies of DOX and DHA were as high as 90%, and the average diameter of the micelles was 64.27 nm. The cellular uptake of DOX from the mixed micelles increased by 1.3 and 1.2 times for MCF-7 and MCF-7/ADR cell lines, respectively. The micelles were more cytotoxic than free DHA-DOX. Surprisingly, the co-loaded mixed micelles exhibited higher antitumor activity, while the systemic toxicity was reduced during the treatment. Therefore, the DOX and DHA mixed micelle might be a potential, effective, and less toxic drug-delivery system for cancer therapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Doxorrubicina/administração & dosagem , Polietilenoglicóis/química , Polivinil/química , Vitamina E/química , Antibióticos Antineoplásicos/farmacologia , Antimaláricos/farmacologia , Artemisininas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Combinação de Medicamentos , Feminino , Humanos , Células MCF-7 , Micelas
6.
Drug Dev Ind Pharm ; 44(9): 1409-1416, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29718714

RESUMO

BACKGROUND: Although piperine can inhibit cells of tumors, the poor water solubility restricted its clinical application. This paper aimed to develop mixed micelles based on Soluplus® and D-α-tocopherol polyethylene glycol succinate (TPGS) to improve the aqueous solubility and anti-cancer effect. METHODS: Piperine-loaded mixed micelles were prepared using a thin-film hydration method, and their physicochemical properties were characterized. The cellular uptake of the micelles was confirmed by confocal laser scanning microscopy in A549 lung cancer cells and HepG2 liver cancer cells. In addition, cytotoxicity of the piperine mixed micelles was studied in A549 lung cancer cells and HepG2 liver cancer cells. Free piperine or piperine-loaded Soluplus®/TPGS mixed micelles were administered at an equivalent dose of piperine at 3.2 mg/kg via a single intravenous injection in the tail vain for the pharmacokinetic study in vivo. RESULTS: The diameter of piperine-loaded Soluplus®/TPGS (4:1) mixed micelles was about 61.9 nm and the zeta potential -1.16 ± 1.06 mV with 90.9% of drug encapsulation efficiency and 4.67% of drug-loading efficiency. Differential scanning calorimetry (DSC) studies confirmed that piperine is encapsulated by the Soluplus®/TPGS. The release results in vitro showed that the piperine-loaded Soluplus®/TPGS mixed micelles presented sustained release behavior compared to the free piperine. The mixed micelles exhibited better antitumor efficacy compared to free piperine and physical mixture against in A549 and HepG2 cells by MTT assay. The pharmacokinetic study revealed that the AUC of piperine-loaded mixed micelles was 2.56 times higher than that of piperine and the MRT for piperine-loaded mixed micelles was 1.2-fold higher than piperine (p < .05). CONCLUSION: The results of the study suggested that the piperine-loaded mixed micelles developed might be a potential nano-drug delivery system for cancer chemotherapy. These results demonstrated that piperine-loaded Soluplus®/TPGS mixed micelles are an effective strategy to deliver piperine for cancer therapy.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Benzodioxóis/química , Benzodioxóis/farmacologia , Neoplasias/tratamento farmacológico , Piperidinas/química , Piperidinas/farmacologia , Polietilenoglicóis/química , Alcamidas Poli-Insaturadas/química , Alcamidas Poli-Insaturadas/farmacologia , Polivinil/química , Vitamina E/química , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Células Hep G2 , Humanos , Masculino , Micelas , Ratos Sprague-Dawley , Solubilidade/efeitos dos fármacos
7.
Sci Total Environ ; 944: 173799, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38852863

RESUMO

Micro-nanoplastics (MNPs) pollution as a global environmental issue has received increasing interest in recent years. MNPs can enter and accumulate in the organisms including human beings mainly via ingestion and inhalation, and large amounts of foodborne MNPs have been frequently detected in human intestinal tracts and fecal samples. MNPs regulate the structure composition and metabolic functions of gut microbiota, which may cause the imbalance of intestinal ecosystems of the hosts and further mediate the occurrence and development of various diseases. In addition, a growing number of MNPs-degrading strains have been isolated from organismal feces. MNPs-degraders colonize the plastic surfaces and form the biofilms, and the long-chain polymers of MNPs can be biologically depolymerized into short chains. In general, MNPs are gradually degraded into small molecule substances (e.g., N2, CH4, H2O, and CO2) via a series of enzymatic catalyses, mainly including biodeterioration, fragmentation, assimilation, and mineralization. In this review, we outline the current progress of MNPs effects on gut microbiota and MNPs degradation by gut microbiota, which provide a certain theoretical basis for fully understanding the knowledge gaps on MNPs-related biological effect and biodegradation.


Assuntos
Biodegradação Ambiental , Microbioma Gastrointestinal , Microbioma Gastrointestinal/fisiologia , Humanos , Microplásticos , Nanopartículas , Poluentes Ambientais/metabolismo
8.
Int J Biol Macromol ; 265(Pt 2): 131118, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38522685

RESUMO

Conductive hydrogels are widely used as sensors in wearable devices. However, hydrogels cannot endure harsh low-temperature environments. Herein, a new regulatory system based on natural ice-structuring proteins (ISPs) and cellulose nanofibers (CNFs) is introduced into hydrogel network consisting of chemically crosslinked network of copolymerized acrylamide and 2-acrylamide-2-methylpropanesulfonic acid, and physically crosslinked polyvinyl alcohol chains, affording an anti-freezing hydrogel with high conductivity (2.63 S/m). These hydrogels show excellent adhesion behavior to various matrices (including aluminum, glass, pigskin, and plastic). Their mechanical properties are significantly improved with the increase in CNF content (tensile strength of 106.4 kPa, elastic modulus of 133.8 kPa). In addition, ISPs inhibit the growth of ice. This endows the hydrogels with anti-freezing property and allows them to maintain satisfactory mechanical properties, conductivity and sensing properties below zero degrees. Moreover, this hydrogel shows high sensitivity to tensile and compressive deformation (GF = 5.07 at 600-800 % strain). Therefore, it can be utilized to develop strain-type pressure sensors that can be attached directly to human skin for detecting various body motions accurately, reliably, and stably. This study proposes a simple strategy to improve the anti-freezing property of hydrogels, which provides new insights for developing flexible hydrogel electronic devices for application in winter sports.


Assuntos
Nanofibras , Humanos , Acrilamida , Caspase 1 , Celulose , Condutividade Elétrica , Hidrogéis
9.
Environ Pollut ; 341: 122897, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37949158

RESUMO

Residual plastic films in soils are posing a potential threat to agricultural ecosystem. However, little is known about the impacts of microplastics (MPs) derived from biodegradable and non-biodegradable plastic films on plant-soil systems. Here, we carried out a pot experiment using soil-cultivated lettuce treated by two types of MPs, degradable poly(butylene adipate-co-terephthalate) (PBAT-MPs) and non-biodegradable polyethylene (PE-MPs). MPs resulted in different degrees of reduction in shoot biomass, chlorophyll content, photosynthetic parameters, and leaf contents of nitrogen (N), phosphorus (P), and potassium (K), accelerated accumulation of hydrogen peroxide and superoxide, and increased malondialdehyde content in lettuce leaves. Moreover, MPs obviously decreased contents of total N, nitrate, ammonium, and available K in soils, and increased available P, thus altering soil nutrient availability. MPs also significantly decreased proportions of macroaggregates, and decreased soil electrical conductivity and microbial activity. PBAT-MPs had significantly greater impacts on oxidative damage, photosynthetic rate, soil aggregation, microbial activity, and soil ammonium than those of PE-MPs. Our results suggested that MPs caused oxidative damages, nutrient uptake inhibition, soil properties alteration, ultimately leading to growth reduction, and PBAT-MPs exhibited stronger impacts. Therefore, it is urgent to further study the ecological effects of MPs, especially biodegradable MPs, on soil-plant systems.


Assuntos
Compostos de Amônio , Lactuca , Solo , Ecossistema , Microplásticos , Plásticos
10.
J Colloid Interface Sci ; 630(Pt B): 776-785, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36356445

RESUMO

Exposure to ammonia (NH3) is known harmful to health, environment and industrial facilities, hence it is important for the trace detection of NH3. Herein, for the first time, ultrasensitive room temperature NH3 sensors are realized by assembling carbon quantum dots (CQDs) on free-standing ultrathin coordination polymers (CPs) nanosheets (Co[Ni(CN)4]) with an average thickness of ∼2.5 nm, which demonstrate excellent sensitivity (Ra/Rg = 87.7 to 30 ppm), fast gas response speed (∼10 s to 30 ppm), remarkable repeatability, high selectivity, good long-term stability and low limit of theoretical detection (∼8 ppb) toward NH3 gas. The NH3 gas sensor enhancement through incorporation of CQDs provides a simple and environment-friendly strategy for further improving sensor property of CPs nanosheets. This work provides an effective way to construct new electrode materials for high-performance gas sensor devices via the rational design.


Assuntos
Pontos Quânticos , Carbono , Amônia , Polímeros
11.
J Control Release ; 349: 940-953, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35870569

RESUMO

Atherosclerotic cardiovascular diseases remain the leading causes of morbidity and mortality worldwide. Cholesterol crystals in atherosclerotic plaques play an essential role in atherosclerosis progression. However, no clinical drugs have been used for removing cholesterol crystals from plaque to counter atherosclerosis. Previous studies identified the hydrophobic domain of lipid bilayer in liposomes acted as sinks for solubilizing hydrophobic cholesterol. Moreover, adjusting the composition of the lipid bilayer in liposomes can enhance its hydrophobic molecule loading capacity. Therefore, in this study, ginsenosides Rb1 (Rb1), one of main active components of ginseng which has a similar structure to cholesterol, is anchored into soy phospholipids bilayer with its hydrophobic region to prepare nano-sponge-like liposomes (Rb1-LPs), aiming to amplify the solubilization of cholesterol in lipid bilayer. For targeting delivery to atherosclerotic plaques, Annexin V (AnxV), a protein that can specifically recognize phosphatidylserine upregulated in atherosclerotic plaques, is applied to decorate the surface of Rb1-LPs by click reaction to obtain the final preparation of AnxV-Rb1-LPs. The in vitro studies showed that incorporating Rb1 into lipid bilayer remarkably increased the affinity of the lipid bilayer to free cholesterol and the solubilization of cholesterol crystals. Additionally, nano-sponge-like liposomes could efficiently reduce the accumulation of cholesterol crystals and improve cholesterol efflux, finally inhibiting inflammation and apoptosis in cholesterol-laden cells. Furthermore, AnxV-Rb1-LPs could efficiently accumulate in atherosclerotic plaques after intravenous injection, exert nano-sponge-like functions to remove intra- and extracellular cholesterol crystals, ultimately alleviating inflammation and apoptosis in atherosclerotic plaques for antiatherosclerosis. Therefore, AnxV-Rb1-LPs provide a potential strategy for removing cholesterol crystals in atherosclerotic plaques and can be further utilized in other diseases with excessive cholesterol accumulation.


Assuntos
Aterosclerose , Ginsenosídeos , Placa Aterosclerótica , Anexina A5 , Aterosclerose/tratamento farmacológico , Colesterol/química , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Humanos , Inflamação , Bicamadas Lipídicas , Lipopolissacarídeos , Lipossomos/uso terapêutico , Fosfatidilserinas , Placa Aterosclerótica/tratamento farmacológico
12.
Int J Nanomedicine ; 16: 1575-1586, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33664572

RESUMO

BACKGROUND: Exosomes are a type of membrane vesicles secreted by living cells. Recent studies suggest exosome-like nanovesicles (ELNVs) from fruits and vegetables are involved in tissue renewal process and functional regulation against inflammatory diseases or cancers. However, there are few reports on ELNVs derived from medicinal plants. METHODS: ELNVs derived from Asparagus cochinchinensis (Lour.) Merr. (ACNVs) were isolated and characterized. Cytotoxicity, antiproliferative and apoptosis-inducing capacity of ACNVs against hepatoma carcinoma cell were assessed. The endocytosis mechanism of ACNVs was evaluated on Hep G2 cells in the presence of different endocytosis inhibitors. In vivo distribution of ACNVs was detected in healthy and tumor-bearing mice after scavenger receptors (SRs) blockade. PEG engineering of ACNVs was achieved through optimizing the pharmacokinetic profiles. In vivo antitumor activity and toxicity were evaluated in Hep G2 cell xenograft model. RESULTS: ACNVs were isolated and purified using a differential centrifugation method accompanied by sucrose gradient ultracentrifugation. The optimized ACNVs had an average size of about 119 nm and showed a typical cup-shaped nanostructure containing lipids, proteins, and RNAs. ACNVs were found to possess specific antitumor cell proliferation activity associated with an apoptosis-inducing pathway. ACNVs could be internalized into tumor cells mainly via phagocytosis, but they were quickly cleared once entering the blood. Blocking the SRs or PEGylation decoration prolonged the blood circulation time and increased the accumulation of ACNVs in tumor sites. In vivo antitumor results showed that PEGylated ACNVs could significantly inhibit tumor growth without side effects. CONCLUSION: This study provides a promising functional nano platform derived from edible Asparagus cochinchinensis that can be used in antitumor therapy with negligible side effects.


Assuntos
Asparagaceae/química , Carcinoma Hepatocelular/patologia , Exossomos/metabolismo , Neoplasias Hepáticas/patologia , Nanopartículas/química , Nanotecnologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/efeitos adversos , Nanopartículas/ultraestrutura , Polietilenoglicóis/química , Distribuição Tecidual/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Carbohydr Polym ; 254: 117461, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357920

RESUMO

In the work, the non-woven cellulose acetate (CA) nanofiber mats were prepared via electrospinning, and CA nanofiber were incorporated into the core layer of the high-pressure laminates (HPLs). When the concentration of CA was 16 wt%, SEM images demonstrated that the morphology of the CA nanofiber mat was the best, with an average diameter of 654±246 nm. When CA nanofiber mats were incorporated into the core layer of HPLs, the mechanical properties of the resulted HPLs composites were significantly improved. Specifically, the tensile strength and elongation at break of the nanofiber mats reinforced HPLs composites increased remarkably to 40.8 ±1.1 MPa and 27.9 ± 0.9 %, respectively, which were nearly 6 times and 4.4 times higher than those of the pure HPLs. Furthermore, the incorporation of the CA nanofiber mats also significantly improved the flame retardancy of the HPLs, which was revealed from the thermogravimetric analysis (TGA) results.


Assuntos
Celulose/análogos & derivados , Materiais de Construção/análise , Técnicas Eletroquímicas , Nanofibras/química , Celulose/química , Celulose/ultraestrutura , Retardadores de Chama/análise , Formaldeído/química , Humanos , Nanofibras/ultraestrutura , Pressão , Resistência à Tração
14.
J Biomed Mater Res A ; 106(8): 2131-2140, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29633582

RESUMO

Expanded poly(tetrafluoroethylene) (ePTFE) has been widely used as a vascular graft material due to the fact that it is durable, porous, flexible, and inert. However, ePTFE grafts easily induce thrombosis, calcification and neointimal hyperplasia in small-diameter (<6 mm) graft bypass surgeries and thus cause surgical failure. Therefore, it is necessary to improve the in vitro and in vivo performances of ePTFE grafts. In this work, we first prepared a polyurethane/polyurethane nanoparticles (PU/PU-NPs) composite film by a simple cosedimentation method. Compared with the pure PU film, the blood compatibility and the cell compatibility of the PU/PU-NPs composite film were significantly improved. Then, we constructed a PU/PU-NPs/ePTFE vascular patch (PPVP) by coating PU and PU-NPs onto the surface of an ePTFE graft. PU-NP modification endowed the ePTFE graft with the nanopatterned surface similar to the luminal surface of a blood vessel. PU NPs and the structural likeness of the surface synergistically optimized the overall performance, and thus improved the blood and cell compatibilities, effectively inhibited platelet adhesion, enhanced cell attachment and proliferation, and facilitated the formation of endothelial tissue-endothelialization. The abdominal artery patched with PPVP was not blocked and the endothelialization was achieved 30 days after the implantation. All the results taken together indicate that PPVP may be a promising alternative for a vascular patch. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2131-2140, 2018.


Assuntos
Prótese Vascular , Endotélio Vascular/fisiologia , Nanopartículas/química , Politetrafluoretileno/química , Poliuretanos/química , Animais , Forma Celular , Sobrevivência Celular , Implantes Experimentais , Camundongos , Nanopartículas/ultraestrutura , Adesividade Plaquetária , Fatores de Tempo
15.
J Colloid Interface Sci ; 485: 91-98, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27657837

RESUMO

BACKGROUND: Nanosuspension is one of the most promising strategies to improve the oral bioavailability of insoluble drugs. The existing techniques applied to produce nanosuspensions are classified as "bottom-up" or "top-down" methods, or a combination of both. Curcumin (CUR), a Biopharmaceutics Classification System (BCS) class IV substance, is a promising drug candidate in view of its good bioactivity, but its use is limited due to its poor solubility and permeability. In the present study, CUR nanosuspensions were developed to enhance CUR oral bioavailability using a cost-effective method different from conventional techniques. RESULTS: The physicochemical properties of CUR nanosuspensions were characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The crystalline state of CUR in different nanosuspensions analyzed using differential scanning calorimeter (DSC) and X-ray diffraction analysis (PXRD) confirmed its amorphous state. In vitro dissolution degree of the prepared CUR nanosuspensions using TPGS or Brij78 as stabilizer was greatly increased. Pharmacokinetic studies demonstrated that the oral bioavailability of CUR was increased 3.18 and 3.7 times after administration of CUR/TPGS nanosuspensions or CUR/Brij78 nanosuspensions, when compared with the administration of CUR suspension. CONCLUSIONS: CUR nanosuspensions produced by our cost-effective method could improve its oral bioavailability. In addition, the low-cost and time-saving method reported here is highly suitable for a fast and inexpensive preparation.


Assuntos
Curcumina/farmacocinética , Nanoestruturas/química , Polietilenoglicóis/química , Vitamina E/química , Administração Oral , Animais , Disponibilidade Biológica , Dióxido de Carbono , Curcumina/química , Curcumina/economia , Estabilidade de Medicamentos , Masculino , Nanoestruturas/economia , Nanoestruturas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Suspensões
16.
Int J Nanomedicine ; 12: 7963-7977, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29133981

RESUMO

To achieve enhanced physical stability of poly(ethylene glycol)-poly(d,l-lactide) polymeric micelles (PEG-PDLLA PMs), a mixture of methoxy PEG-PDLLA-polyglutamate (mPEG-PDLLA-PLG) and mPEG-PDLLA-poly(l-lysine) (mPEG-PDLLA-PLL) copolymers was applied to self-assembled stable micelles with polyion-stabilized cores. Prior to micelle preparation, the synthetic copolymers were characterized by 1H-nuclear magnetic resonance (NMR) and infrared spectroscopy (IR), and their molecular weights were calculated by 1H-NMR and gel permeation chromatography (GPC). Dialysis was used to prepare PMs with deoxypodophyllotoxin (DPT). Transmission electron microscopy (TEM) images showed that DPT polyion complex micelles (DPT-PCMs) were spherical, with uniform distribution and particle sizes of 36.3±0.8 nm. In addition, compared with nonpeptide-modified DPT-PMs, the stability of DPT-PCMs was significantly improved under various temperatures. In the meantime, the pH sensitivity induced by charged peptides allowed them to have a stronger antitumor effect and a pH-triggered release profile. As a result, the dynamic characteristic of DPT-PCM was retained, and high biocompatibility of DPT-PCM was observed in an in vivo study. These results indicated that the interaction of anionic and cationic charged polyionic segments could be an effective strategy to control drug release and to improve the stability of polymer-based nanocarriers.


Assuntos
Portadores de Fármacos/química , Podofilotoxina/análogos & derivados , Ácido Poliglutâmico/química , Polilisina/química , Animais , Portadores de Fármacos/administração & dosagem , Liberação Controlada de Fármacos , Medicamentos de Ervas Chinesas , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Masculino , Micelas , Peso Molecular , Tamanho da Partícula , Podofilotoxina/administração & dosagem , Podofilotoxina/farmacocinética , Poliésteres/química , Polietilenoglicóis/química , Espectroscopia de Prótons por Ressonância Magnética , Coelhos , Ratos Sprague-Dawley , Eletricidade Estática , Temperatura
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