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1.
Biomacromolecules ; 19(8): 3377-3389, 2018 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-30024744

RESUMEN

Novel polymer amphiphiles with chemical structures designed as zwitterionic analogs of Pluronic block copolymers were prepared by controlled free radical polymerization of phosphorylcholine (PC) or choline phosphate (CP) methacrylate monomers from a difunctional poly(propylene oxide) (PPO) macroinitiator. Well-defined, water-dispersible zwitterionic triblock copolymers, or "zwitteronics", were prepared with PC content ranging from 5 to 47 mol percent and composition-independent surfactant characteristics in water, which deviate from the properties of conventional Pluronic amphiphiles. These PC-zwitteronics assembled into nanoparticles in water, with tunable sizes and critical aggregation concentrations (CACs) based on their hydrophilic-lipophilic balance (HLB). Owing to the lower critical solution temperature (LCST) miscibility of the hydrophobic PPO block in water, PC-zwitteronics exhibited thermoreversible aqueous solubility tuned by block copolymer composition. The chemical versatility of this approach was demonstrated by embedding functionality, in the form of alkyne groups, directly into the zwitterion moieties. These alkynes proved ideal for cross-linking the zwitteronic nanoparticles and for generating nanoparticle-cross-linked hydrogels using UV-initiated thiol-yne "click" chemistry.


Asunto(s)
Poloxámero/análogos & derivados , Tensoactivos/síntesis química , Colina/análogos & derivados , Metacrilatos/química , Nanopartículas/química , Polipropilenos/química
2.
ACS Sens ; 9(1): 502-513, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38193423

RESUMEN

Electric-induced surface-enhanced Raman scattering (E-SERS) has been widely studied for its flexible regulation of SERS after the substrate is prepared. However, the enhancement effect is not sufficiently high in the E-SERS technology reported thus far, and no suitable field of application exists. In this study, a highly sensitive thermoelectrically induced SERS substrate, Ag/graphene/ZnO (AGZ), was fabricated using ZnO nanoarrays (NRs), graphene, and Ag nanoparticles (NPs). Applying a temperature gradient to the ZnO NRs enhanced the SERS signals of the probe molecules by a factor of approximately 20. Theoretical and experimental results showed that the thermoelectric potential enables the simultaneous modulation of the Fermi energy level of graphene and the plasma resonance peak of Ag NPs, resulting in a double enhancement in terms of physical and chemical mechanisms. The AGZ substrate was then combined with a mask to create a wearable thermoelectrically enhanced SERS mask for collecting SARS-CoV-2 viruses and microplastics. Its SERS signal can be enhanced by the temperature gradient created between a body heat source (∼37 °C) and a cold environment. The suitability of this method for virus detection was also examined using a reverse transcription-polymerase chain reaction and SARS-CoV-2 virus antigen detection. This work offers new horizons for research of E-SERS, and its application potential for rapid detection of the SARS-CoV-2 virus and microplastics was also studied.


Asunto(s)
COVID-19 , Grafito , Nanopartículas del Metal , Óxido de Zinc , Humanos , SARS-CoV-2 , Nanopartículas del Metal/química , Microplásticos , Plásticos , Óxido de Zinc/química , Plata/química , COVID-19/diagnóstico
3.
J Hazard Mater ; 457: 131820, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37320903

RESUMEN

The adsorption of toxic substances on polystyrene microplastics (PSMPs) can modify their biological toxicity and exacerbate the threat to human health. The effects of benzo [a] pyrene (B (a) P)-loaded aged PSMPs on colonic barrier integrity remains unclear. Here, we showed that binding environmentally relevant concentrations of B (a) P alteredl̥ the physicochemical features and markedly enhanced the toxicity of PSMPs. Compared to pristine PSMP, PSMP@B (a) P promoted colonic barrier degradation, body weight loss, colon length shortening, oxidative stress (OS), autophagy, inflammation, and bacterial translocation. Microplastic (MP) exposure induced injury to the colon barrier, including tight junction (TJ) and mucosal barriers, via overactivation of the Notch signalling pathway under increased OS in mice and intestinal organoids. Notably, PSMP@B (a) P exposure exacerbated damage to TJ and the mucosal barrier via the overproduction of reactive oxygen species (ROS), which could be related to the release of B (a) P from PSMP@B (a) P induced by the acidic environment of autophagosomes, which in turn exert synergistic toxic effects with PSMPs. Our study elucidates some of the potential molecular mechanisms by which B (a) P enhances PSMP-related intestinal toxicity, which provides a potential therapeutic approach for diseases caused by PSMP@B (a)P and PSMP pollution.


Asunto(s)
Microplásticos , Poliestirenos , Humanos , Animales , Ratones , Anciano , Microplásticos/química , Poliestirenos/química , Plásticos/metabolismo , Benzo(a)pireno/toxicidad , Benzo(a)pireno/metabolismo , Colon , Estrés Oxidativo
4.
BMJ Open ; 12(6): e058075, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35676012

RESUMEN

OBJECTIVE: To compare the safety and effectiveness between biodegradable polymer drug-eluting stents (BP-DES) and durable polymer drug-eluting stents (DP-DES) in patients with acute coronary syndrome (ACS). DESIGN: Meta-analysis of randomised controlled trials (RCTs). PRIMARY AND SECONDARY OUTCOME MEASURES: Major adverse cardiovascular events (MACEs) were considered the primary endpoint. Efficacy endpoints included target vessel revascularisation (TVR) and target lesion revascularisation (TLR). Safety endpoints included all-cause death, cardiac death, target vessel myocardial infarction and stent thrombosis (ST). METHODS: We searched PubMed, Medline, Embase and the Cochrane Controlled Register of Trials for comparative studies of BP-DES and DP-DES in patients with ACS from January 2000 to July 2021. Statistical pooling was performed to estimate incidence using a random-effects model with generic inverse-variance weighting. Risk estimates were computed with 95% CIs. RESULTS: Eight articles with seven RCTs that compared BP-DES and DP-DES in patients with ACS were identified and included in the qualitative and quantitative analyses. There was no difference in the baseline characteristics, except for the number of smoking patients (OR: 1.13, 95% CI 1.03 to 1.24; p=0.008, I2=29%), which was significantly lower in the BP-DES group. The meta-analysis demonstrated that MACEs, efficacy endpoints and safety endpoints were similar between the groups at 1 year. However, the incidence of total ST was significantly different between the BP-DES and DP-DES groups in the follow-up period (p=0.0001). Further analysis showed a statistically significant difference in MACEs (OR: 0.71, 95% CI 0.57 to 0.88; p=0.002, I2=0 %), TLR (OR: 0.71, 95% CI 0.51 to 1.01; p=0.05, I2=0%), TVR (OR: 0.70, 95% CI 0.52 to 0.94; p=0.002, I2=15%), total ST incidence (OR: 0.59, 95% CI 0.46 to 0.77; p=0.0001, I2=48%) and ST incidence (OR: 0.63, 95% CI 0.47 to 0.85; p=0.002, I2=0%) over 2 years. CONCLUSION: This meta-analysis revealed that both stent types demonstrated excellent safety and efficacy profiles at 12 months. However, a slight increase in MACEs, TLR, TVR and ST incidence was observed in the DP-DES group over the 2-year follow-up period, suggesting that BP-DES may be more favourable when treating patients with ACS. TRIAL REGISTRATION NUMBER: NCT00389220.


Asunto(s)
Síndrome Coronario Agudo , Stents Liberadores de Fármacos , Polímeros , Implantes Absorbibles , Síndrome Coronario Agudo/cirugía , Stents Liberadores de Fármacos/efectos adversos , Humanos , Polímeros/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
5.
Cancer Invest ; 29(10): 701-8, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22085274

RESUMEN

In the present study, we have used plasmid-based RNA interference (RNAi) strategy to downregulate the expression of epidermal growth factor receptor (EGFR) in EGFR wild-type (H292) and mutant (H1975) lung tumor models. The targeted knockdown of EGFR by small hairpin RNA not only inhibited growth of H292 xenograft but also inhibited H1975 lung cancer cell and xenograft, which bore L858R/T790M EGFR and was resistant to EGFR tyrosine kinase inhibitors. These data demonstrated that small hairpin RNA was an effective therapy against mutant EGFR-expressing cancer cells and thus considered to be a promising strategy in the treatment of lung cancers.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/terapia , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Neoplasias Pulmonares/terapia , Mutación , ARN Interferente Pequeño/genética , Animales , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular , Ácidos Grasos Monoinsaturados/administración & dosificación , Femenino , Humanos , Liposomas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Ratones , Invasividad Neoplásica , Compuestos de Amonio Cuaternario/administración & dosificación
6.
Environ Pollut ; 240: 764-774, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29778812

RESUMEN

Aluminum (Al) phytotoxicity is a major limitation in the production of crops in the soils with pH ≤ 5. Boron (B) is indispensable nutrient for the development of higher plants and B role has been reported in the alleviation Al toxicity. Trifoliate orange rootstock was grown in two B and two Al concentrations. The results of the present study showed that Al toxicity adversely inhibited root elongation and exhibited higher oxidative stress in terms of H2O2 and O2- under B-deficiency. Additionally, the X-ray diffraction (XRD) analysis confirmed the increase of the cellulose crystallinity in the cell wall (CW). Al-induced remarkable variations in the CW components were prominent in terms of alkali-soluble pectin, 2-keto-3-deoxyoctonic acid (KDO) and the degree of methyl-esterification (DME) of pectin. Interesting, B supply reduced the pectin (alkali-soluble) under Al toxicity. Moreover, the results of FTIR (Fourier transform infrared spectroscopy) and 13C-NMR (13C nuclear magnetic resonance) spectra revealed the decrease of carboxyl groups and cellulose by B application during Al exposure. Furthermore, B supply tended to decrease the Al uptake, CW thickness and callose formation. The study concluded that B could mitigate Al phytotoxicity by shielding potential Al binding sites and by reducing Al induced alterations in the CW cellulose and pectin components.


Asunto(s)
Aluminio/toxicidad , Boro/metabolismo , Estrés Oxidativo/efectos de los fármacos , Pectinas/metabolismo , Poncirus/fisiología , Sustancias Protectoras/metabolismo , Contaminantes del Suelo/toxicidad , Pared Celular/metabolismo , Celulosa , Citrus , Esterificación , Glucanos , Peróxido de Hidrógeno/metabolismo , Suelo
7.
J Control Release ; 145(1): 17-25, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20307599

RESUMEN

Fibroblast growth factor receptors (FGFRs), overexpressed on the surface of a variety of tumor cells and on tumor neovasculature in situ, are potential targets for tumor- and vascular-targeting therapy. This study aimed to develop a FGFR-mediated drug delivery system to target chemotherapeutic agents to FGFR-overexpressed tumor cells and tumor neovasculature endothelial cells in vitro and in vivo. Here we designed a truncated human basic fibroblast growth factor peptide (tbFGF), which was attached to the surface of cationic liposomal doxorubicin (LPs-DOX) and paclitaxel (LPs-PTX) via electrostatic force. Then we characterized the tbFGF-modified liposome (tbFGF-LPs) and examined internalization of doxorubicin in tumor cells (TRAMP-C1, B16) and HUVEC cells in vitro. In vivo, we evaluated the biodistribution and antitumor efficacy of tbFGF-LPs-DOX and tbFGF-LPs-PTX in C57BL/6J mice bearing TRAMP-C1 prostate carcinoma and B16 melanoma, respectively. The tbFGF-LPs-DOX significantly improved the uptake of doxorubicin in TRAMP-C1, B16 and HUVEC cells, respectively. Biodistribution study in B16 tumor-bearing mice showed that tbFGF-LPs-PTX achieved 7.1-fold (72.827+/-7.321mgh/L vs 10.292+/-0.775mgh/L, mean+/-SD, P<0.01) accumulation of paclitaxel in tumor tissue than those of free paclitaxel. More importantly, treatment of tumor-bearing mice with tbFGF-LPs-DOX and tbFGF-LPs-PTX showed the significant inhibition in tumor growth and improvement in survival rate as compared with mice treated with free and liposomal drugs in TRAMP-C1 and B16 tumor models, respectively. Furthermore, repeated intravenous administration of tbFGF-LPs-DOX/PTX did not induce anti-bFGF antibodies. These results suggested that this FGFR-mediated drug delivery system may provide a new treatment strategy for tumors which overexpress FGFRs.


Asunto(s)
Antineoplásicos/administración & dosificación , Portadores de Fármacos/química , Factor 2 de Crecimiento de Fibroblastos/química , Melanoma Experimental/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Cationes , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapéutico , Femenino , Citometría de Flujo , Etiquetado Corte-Fin in Situ , Inyecciones Intravenosas , Liposomas , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Microscopía de Fuerza Atómica , Trasplante de Neoplasias , Paclitaxel/administración & dosificación , Paclitaxel/farmacocinética , Paclitaxel/uso terapéutico , Tamaño de la Partícula , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Unión Proteica , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Propiedades de Superficie
8.
Cancer Biol Ther ; 10(3): 276-81, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20543584

RESUMEN

Basic fibroblast growth factor (bFGF) is a mitogen for endothelial cells, which participates in tumor angiogenesis. Active immunity against bFGF could be a promising approach for the biotherapy of cancer. Because bFGF is abundant in normal and malignant tissues, it is presumably difficult for normal bFGF to induce immunity due to self-tolerance. In addition, previous studies have shown that a complex consisting of a cationic liposome and a non-coding plasmid DNA can be used to stimulate innate immunity. This stimulation initiates a potent cytokine response, which can inhibit tumor growth. To investigate the effects of immunity against bFGF on murine colon carcinomas, we employed an N-, C-terminally truncated basic fibroblast growth factor (tbFGF, of human origin) as an antigen and a liposome-DNA complex as an adjuvant. After six immunizations, a robust bFGF-specific immune response was elicited. Subsequently, inhibition of tumor growth and a significant reduction in tumor vasculature were observed. The antitumor effect was confirmed by adoptive therapy of activated spleen cells from the immunized mice. In vitro, a CTL assay revealed that bFGF-specific cytotoxic T lymphocytes (CTL) resulted in the lysis of mouse microvascular endothelial cells (MS1) rather than that of the CT26 colorectal cancer cells. These results suggest that anti-angiogenesis treatment induced by a bFGF-specific CTLs against microvascular endothelial cells may be a useful method for cancer therapy.


Asunto(s)
Vacunas contra el Cáncer/administración & dosificación , Neoplasias del Colon/inmunología , Neoplasias del Colon/terapia , Factor 2 de Crecimiento de Fibroblastos/inmunología , Secuencia de Aminoácidos , Animales , Vacunas contra el Cáncer/genética , Vacunas contra el Cáncer/inmunología , Neoplasias del Colon/patología , Neoplasias del Colon/prevención & control , ADN/administración & dosificación , Femenino , Factor 2 de Crecimiento de Fibroblastos/administración & dosificación , Factor 2 de Crecimiento de Fibroblastos/genética , Vectores Genéticos/genética , Humanos , Inmunidad Innata/inmunología , Liposomas/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Plásmidos/genética
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