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1.
Kidney Blood Press Res ; 43(4): 1273-1284, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30078011

RESUMEN

BACKGROUND/AIMS: Myocardial ischemia/reperfusion (I/R) injury (MI/RI) is a critical cause of death in patients with heart disease. However, the pharmaco-therapeutical outcome for MI/RI remains unsatisfactory. Innovative approaches for enhancing drug sensitivity and recovering myocardial function in MI/RI treatment are urgently needed. The purpose of this study was to evaluate the protective effects of exenatide-loaded poly(L-lysine)-poly(ethylene glycol)-poly(L-lysine) (PLL-PEG-PLL) nanoparticles (NPs) against MI/RI. METHODS: The size of PLL-PEG-PLL NPs and the loading and release rates of exenatide were determined. The in vitro NP cytotoxicity was evaluated using newborn rat cardiomyocytes. Rats pretreated with free exenatide or exenatide/PLL-PEG-PLL polyplexes were subjected to 0.5-h ischemia and 2-h reperfusion in the left anterior descending coronary artery. The histopathologic lesions were assessed using hematoxylin-eosin staining. The general physiological indices, including blood pressure (BP), heart rate (HR), the left ventricular ejection fraction (LVEF) and end-diastolic pressure (LEVDP), and the left ventricular pressure maximal rate of rising (dp/dtmax), were monitored using a non-invasive blood pressure analyzer and color Doppler echocardiography. The antioxidative activity in the myocardial tissue was measured. The myocardial enzymatic activity was further estimated by determining the serum levels of creatine kinase (CK), lactate dehydrogenase (LDH), cardiac troponin T (cTnT), and glucagon-like peptide-1 (GLP-1), as well as the expression of GLP-1R in the myocardial tissue. RESULTS: Exenatide preconditioning attenuated the oxidative stress injury and promoted the myocardial function in I/R-induced myocardial injury, while the application of block copolymer PLL-PEG-PLL as a potential exenatide nanocarrier with sustained release significantly enhanced the bioavailability of exenatide. CONCLUSION: The block copolymer PLL-PEG-PLL may function as a potent exenatide nanocarrier for augmenting pharmacotherapy against MI/RI with unprecedented clinical benefits. Further study is needed to better clarify the underlying mechanisms.


Asunto(s)
Precondicionamiento Isquémico Miocárdico/métodos , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Nanopartículas/química , Péptidos/farmacología , Ponzoñas/farmacología , Animales , Animales Recién Nacidos , Portadores de Fármacos/química , Exenatida , Hipoglucemiantes , Incretinas , Masculino , Estrés Oxidativo/efectos de los fármacos , Péptidos/farmacocinética , Péptidos/uso terapéutico , Polietilenglicoles/uso terapéutico , Polilisina/análogos & derivados , Polilisina/uso terapéutico , Ratas , Ratas Sprague-Dawley , Ponzoñas/farmacocinética , Ponzoñas/uso terapéutico
2.
Biomacromolecules ; 18(12): 3869-3880, 2017 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-29032674

RESUMEN

Current research is mainly trending toward addressing the development of multifunctional nanocarriers that could precisely reach disease sites, release drugs in a controlled-manner, and act as an imaging agent for both diagnosis and targeted therapy. In this study, a pH-sensitive theranostic nanoplatform as a promising dual-functional nanovector for tumor therapy and computed tomography (CT) imaging was developed. The 21-arm star-like triblock polymer of ß-cyclodextrin-{poly(ε-caprolactone)-poly(2-aminoethyl methacrylate)-poly[poly(ethylene glycol) methyl ether methacrylate]}21 [ß-CD-(PCL-PAEMA-PPEGMA)21] with stable unimolecular micelles formed in aqueous solution was first synthesized by combined ROP with ARGET ATRP techniques and then was used as a template for fabricating gold nanoparticles (AuNPs) with uniform sizes and excellent colloidal stability in situ followed by the encapsulation of doxorubicin (DOX) with maximum entrapment efficiency up to 60% to generate the final product ß-CD-(PCL-PAEMA-PPEGMA)21/AuNPs/DOX. Furthermore, dissipative particle dynamics (DPD) simulations revealed further details of the formation process of unimolecular micelles and the morphologies and distributions of AuNPs and DOX. Almost 80% of DOX was released in 120 h in an acidic tumoral environment in an in vitro drug release experiment, and the experiments both in vitro and in vivo demonstrated the fact that ß-CD-(PCL-PAEMA-PPEGMA)21/AuNPs/DOX exhibited similar antitumor efficacy to free DOX and effective CT imaging performance. Therefore, we believe this structurally stable unimolecular micelle-based nanoplatform synergistically integrated with anticancer drug delivery and CT imaging capabilities hold great promise for future cancer theranostics.


Asunto(s)
Doxorrubicina/química , Doxorrubicina/farmacología , Oro/química , Nanopartículas del Metal/química , Neoplasias/tratamiento farmacológico , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Células Hep G2 , Humanos , Concentración de Iones de Hidrógeno , Metacrilatos/química , Ratones , Ratones Endogámicos NOD , Ratones SCID , Micelas , Tamaño de la Partícula , Poliésteres/química , Polietilenglicoles/química , Polímeros/química , Ácidos Polimetacrílicos , Nanomedicina Teranóstica/métodos , Tomografía Computarizada por Rayos X/métodos
3.
Biomacromolecules ; 15(2): 618-27, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24405043

RESUMEN

Uniaxially aligned cellulose nanofibers with well oriented cellulose nanocrystals (CNCs) embedded were fabricated via electrospinning using a rotating drum as the collector. Scanning electron microscope (SEM) images indicated that most cellulose nanofibers were uniaxially aligned. The incorporation of CNCs into the spinning dope resulted in more uniform morphology of the electrospun cellulose/CNCs nanocomposite nanofibers (ECCNN). Polarized light microscope (PLM) and transmission electron microscope (TEM) showed that CNCs dispersed well in ECCNN nonwovens and achieved considerable orientation along the long axis direction. This unique hierarchical microstructure of ECCNN nonwovens gave rise to remarkable enhancement of their physical properties. By incorporating 20% loading (in weight) of CNCs, the tensile strength and elastic modulus of ECCNN along the fiber alignment direction were increased by 101.7 and 171.6%, respectively. Their thermal stability was significantly improved as well. In addition, the ECCNN nonwovens were assessed as potential scaffold materials for tissue engineering. It was elucidated from MTT tests that the ECCNN were essentially nontoxic to human cells. Cell culture experiments demonstrated that cells could proliferate rapidly not only on the surface but also deep inside the ECCNN. More importantly, the aligned nanofibers of ECCNN exhibited a strong effect on directing cellular organization. This feature made the scaffold particularly useful for various artificial tissues or organs, such as blood vessel, tendon, nerve, and so on, in which cell orientation was crucial for their performance.


Asunto(s)
Celulosa/química , Nanofibras/química , Nanopartículas/química , Ingeniería de Tejidos , Andamios del Tejido , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Saco Dental/química , Saco Dental/citología , Humanos
4.
BMC Med Genomics ; 16(1): 292, 2023 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-37974187

RESUMEN

PURPOSE: This study reported the first case of Kohlschütter-Tönz syndrome (KTS) in China and reviewed the literature of the reported cases. METHODS: This patient was registered at the Children's Hospital of Chongqing Medical University. The patient's symptoms and treatments were recorded in detail, and the patient was monitored for six years. We employed a combination of the following search terms and Boolean operators in our search strategy: Kohlschütter-Tönz syndrome, KTS, and ROGDI. These terms were carefully selected to capture a broad range of relevant publications in PubMed, Web of Science, WHO Global Health Library, and China National Knowledge Infrastructure, including synonyms, variations, and specific terms related to KTS. The pathogenicity of the variants was predicted using SpliceAI and MutationTaster, and the structures of the ROGDI mutations were constructed using I-TASSER. RESULTS: This is the first case report of KTS in China. Our patient presented with epilepsy, global developmental delay, and amelogenesis imperfecta. A trio-WES revealed homozygous mutations in ROGDI (c.46-37_46-30del). The brain magnetic resonance imaging (MRI) and video electroencephalogram (VEEG) were normal. The efficacy of perampanel (PMP) in treating seizures and intellectual disability was apparent. Furthermore, 43 cases of ROGDI-related KTS were retrieved. 100% exhibited epilepsy, global developmental delay, and amelogenesis imperfecta. 17.2% received a diagnosis of attention deficit hyperactivity disorder (ADHD), and 3.4% were under suspicion of autism spectrum disorder (ASD). Language disorders were observed in all patients. Emotional disorders, notably self-harm behaviors (9.1%), were also reported. CONCLUSION: ROGDI-related KTS is a rare neurodegenerative disorder, characterized by three classic clinical manifestations: epilepsy, global developmental delay, and amelogenesis imperfecta. Moreover, patients could present comorbidities, including ADHD, ASD, emotional disorders, and language disorders. PMP may be a potential drug with relatively good efficacy, but long-term clinical trials are still needed.


Asunto(s)
Amelogénesis Imperfecta , Trastorno del Espectro Autista , Epilepsia , Trastornos del Lenguaje , Niño , Humanos , Amelogénesis Imperfecta/genética , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Proteínas de la Membrana/genética , Proteínas Nucleares/genética
5.
Nat Commun ; 13(1): 5804, 2022 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-36192544

RESUMEN

Naturally derived biopolymers have attracted great interest to construct photonic materials with multi-scale ordering, adaptive birefringence, chiral organization, actuation and robustness. Nevertheless, traditional processing commonly results in non-uniform organization across large-scale areas. Here, we report magnetically steerable uniform biophotonic organization of cellulose nanocrystals decorated with superparamagnetic nanoparticles with strong magnetic susceptibility, enabling transformation from helicoidal cholesteric (chiral nematic) to uniaxial nematic phase with near-perfect orientation order parameter of 0.98 across large areas. We demonstrate that magnetically triggered high shearing rate of circular flow exceeds those for conventional evaporation-based assembly by two orders of magnitude. This high rate shearing facilitates unconventional unidirectional orientation of nanocrystals along gradient magnetic field and untwisting helical organization. These translucent magnetic films are flexible, robust, and possess anisotropic birefringence and light scattering combined with relatively high optical transparency reaching 75%. Enhanced mechanical robustness and uniform organization facilitate fast, multimodal, and repeatable actuation in response to magnetic field, humidity variation, and light illumination.


Asunto(s)
Materiales Inteligentes , Biopolímeros , Celulosa/química , Fenómenos Magnéticos , Magnetismo
6.
Phys Chem Chem Phys ; 13(32): 14606-10, 2011 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-21769332

RESUMEN

Oil contaminated water is a common problem in the world, thus to effectively separate water and oil is an urgent task for us to resolve. By control of surface wettability of a solid substrate, both superhydrophobicity and superoleophilicity on a film can be realized, which is necessary for water and oil separation. Here we report a stable superhydrophobic and superoleophilic ZnO-coated stainless steel mesh film with special hierarchical micro/nanostructures that can be used to separate a water and oil mixture effectively. Namely, the film is superhydrophobic and water cannot penetrate the mesh film because of the large negative capillary effect, while the film is superoleophilic and liquid paraffin oil can spread out quickly and permeate the mesh film spontaneously due to the capillary effect. A detailed investigation indicates that microscale and nanoscale hierarchical structures and the appropriate size of the microscale mesh pores on the mesh films play an important role in obtaining the excellent water and oil separation property. This work provides an alternative to current separation meshes and is promising in various important applications such as separation and filtration, lab-on-a-chip devices and micro/nanofluidic devices.


Asunto(s)
Membranas Artificiales , Nanoestructuras/química , Aceites/química , Acero Inoxidable/química , Agua/química , Óxido de Zinc/química , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Propiedades de Superficie , Humectabilidad
7.
ACS Nano ; 14(11): 14675-14685, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-32910639

RESUMEN

Attaining high mechanical strength and flexibility for chiral nematic biopolymer composites without compromising their vivid optical iridescence is an intriguing but challenging task. Traditional cellulose nanocrystal (CNC) blend nanocomposite films typically lose their coloration and display weak mechanical performance due to poor load transfer between needle-like nanocrystals and the collapse of a twisted organization. Herein, we report a design of robust laminated biocomposites with an alternatively stacked chiral nematic CNC phase and a random cellulose nanofiber (CNF) phase via a hydrogen-bonding-assisted layer-by-layer method. In contrast to the traditional biopolymer blends, the alternating CNC-CNF stacked films possess many-fold enhancement in both mechanical strength and toughness with their vivid structural colors highly preserved. We suggest that the enriched hydrogen bonding and partial limited entanglements at the interfaces between the helicoidal and random phases are responsible for enhancing the mechanical performance of robust biocomposites with brilliant iridescent colors. Such organized cellulose-cellulose biocomposites with alternating helicoidal-random phases fabricated by a facile sequential strategy may facilitate the development of sustainably sourced, damage-tolerant, and photonic films for bioenabled display technologies, security indicators, soft robotics, camouflages, and pressure sensors.


Asunto(s)
Nanocompuestos , Nanofibras , Nanopartículas , Celulosa , Fenómenos Físicos
8.
Adv Colloid Interface Sci ; 278: 102141, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32213350

RESUMEN

In recent years, zwitterionic polymers have been frequently reported to modify various surfaces to enhance hydrophilicity, antifouling and antibacterial properties, which show significant potentials particularly in biological systems. This review focuses on the fabrication, properties and various applications of zwitterionic polymer grafted surfaces. The "graft-from" and "graft-to" strategies, surface grafting copolymerization and post zwitterionization methods were adopted to graft lots type of the zwitterionic polymers on different inorganic/organic surfaces. The inherent hydrophilicity and salt affinity of the zwitterionic polymers endow the modified surfaces with antifouling, antibacterial and lubricating properties, thus the obtained zwitterionic surfaces show potential applications in biosystems. The zwitterionic polymer grafted membranes or stationary phases can effectively separate plasma, water/oil, ions, biomolecules and polar substrates. The nanomedicines with zwitterionic polymer shells have "stealth" effect in the delivery of encapsulated drugs, siRNA or therapeutic proteins. Moreover, the zwitterionic surfaces can be utilized as wound dressing, self-healing or oil extraction materials. The zwitterionic surfaces are expected as excellent support materials for biosensors, they are facing the severe challenges in the surface protection of marine facilities, and the dense ion pair layers may take unexpected role in shielding the grafted surfaces from strong electromagnetic field.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Polímeros/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Incrustaciones Biológicas/prevención & control , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Nanomedicina , Polimerizacion , Polímeros/síntesis química , Polímeros/química , Sales (Química)/química , Propiedades de Superficie
9.
ACS Appl Mater Interfaces ; 12(1): 1378-1386, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31818093

RESUMEN

Graphene aerogel (GA) as a rising multifunctional material has demonstrated great potential for energy storage and conversion, environmental remediation, and high-performance sensors or actuators. However, the commercial use of GA is obstructed by its fragility and high cost. Herein, by a simple stirring-induced foaming of the mixed aqueous solutions of natural rubber latex (NRL) and graphene oxide liquid crystal (GOLC), we obtained tough, ultralight (4.6 mg cm-3), high compressibility (>90%), and water-adhesive graphene/NRL hybrid aerogel (GA/NRL). Of particular note, the NRL particles are conformally wrapped by graphene layers to form a sandwichlike cell wall with a biomimetic rose-petal-like surface. These distinct hierarchical structures endow GA/NRL not only with high toughness to bear impact, torsion (>90°), and even ultrasonication but also with strong adhesion to water. As proof of concept, the utilization of the as-prepared GA/NRL for collecting water droplets suspended in moist air and its improved solar-thermal harvest capacity have been demonstrated. This facile, green, and cost-effective strategy opens a new route for tailoring the microstructure and functionality of GA, which will facilitate its large-scale production and commercial application.


Asunto(s)
Adhesivos/química , Biomimética , Geles/química , Grafito/química , Pared Celular/efectos de los fármacos , Geles/farmacología , Látex/química , Conformación Molecular/efectos de los fármacos , Goma/química , Propiedades de Superficie , Agua/química
10.
Int J Biol Macromol ; 140: 851-857, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31470051

RESUMEN

Alternaria tenuissima infects stored potatoes, and causes tuber rot, resulting in significant economic losses. As a naturally-occurring polysaccharide (poly-ß-(1 → 4) N-acetyl-D-glucosamine), chitosan has been reported to be an eco-friendly alternative to synthetic fungicides for the control of postharvest diseases on agricultural commodities. In this study, application of 0.25-1.25 g/L chitosan significantly inhibited spore germination and mycelial growth of A. tenuissima in vitro, with the greatest inhibitory effect observed at the highest concentration. Cytological and biochemical analysis of A. tenuissima spores indicated that exposure to 1.25 g/L chitosan significantly damaged the plasma membrane and increased the level of lipid oxidation. Gene expression analysis in potato tuber revealed that an application of 1.25 g/L chitosan induced the expression of defense-related genes, including catalase, peroxidase, polyphenol oxidase, chitinase and ß-1,3-glucanase, and the level of flavonoids and lignin. Chitosan effectively controlled tuber rot caused by A. tenuissima. Collectively, results of the current study indicate that the ability of chitosan to reduce Alternaria rot in stored potato tubers is due to its direct antifungal activity and its ability to induce defense responses in potato tuber tissues. Chitosan may have the potential as a substitute for synthetic fungicides to reduce postharvest losses in potato.


Asunto(s)
Alternaria , Quitosano/química , Resistencia a la Enfermedad , Enfermedades de las Plantas/microbiología , Tubérculos de la Planta/química , Tubérculos de la Planta/microbiología , Solanum tuberosum/química , Solanum tuberosum/microbiología , Biomasa , Quitosano/farmacología , Resistencia a la Enfermedad/efectos de los fármacos , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación , Lignina , Peroxidación de Lípido , Esporas Fúngicas
11.
Colloids Surf B Biointerfaces ; 163: 29-40, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29278801

RESUMEN

An amphiphilic copolymer poly(ε-caprolactone)-ss-poly(2-(dimethylamino) ethyl methacrylate), PCL-SS-PDMAEMA, was designed and synthesized using ROP and ARGET ATRP methods. Dual stimulus responsive micelles were prepared by the self-assembly of PCL-SS-PDMAEMA. PDMAEMA could respond to acid conditions with protonation, followed by enhanced hydrophilicity and swelling of the micellar shell. In addition, the cleavable joint disulfide bond between the core and shell was disrupted when exposed to an abundance of the reductant reductive glutathione GSH, leading to the disassembly of the micellar structure. The smart response behavior can be used for intracellular controlled drug release in tumor cells. In terms of "theranostics" with higher therapy effect, the tool for tumor imaging and diagnose through computed tomography (CT) was considered with the loading of gold nanoparticles (GNPs). GNPs with good distribution were prepared by means of in situ reduction by PDMAEMA block and stabilized by the micelles. Polymeric micelles were used to load the anticancer drug doxorubicin (DOX) in the hydrophobic core and GNPs in the hydrophilic PDMAEMA shell. Subsequently, the micellar theranostics platform combining chemotherapy and CT diagnose was obtained. The pH- or redox-triggered drug release profiles suggesting that the DOX/GNPs-loaded micelles facilitated controlled release in response to different simulated microenvironments. Cellular uptake study was carried out, indicating that the micelles could be fast internalized within several hours. MTT assay showing significant inhibition against HepG2 and MCF-7 cells for the DOX/GNPs-loaded micelles. Finally, the in vitro CT imaging assay indicated the good CT diagnosis potential of DOX/GNPs-loaded micelles. The micelle simultaneously loaded with DOX and GNPs represent a promising theranostics platform for efficient cancer chemotherapy and diagnosis.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Preparaciones de Acción Retardada/síntesis química , Doxorrubicina/farmacología , Portadores de Fármacos/síntesis química , Nanopartículas del Metal/química , Tomografía Computarizada por Rayos X/métodos , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/metabolismo , Doxorrubicina/química , Doxorrubicina/metabolismo , Composición de Medicamentos/métodos , Liberación de Fármacos , Glutatión/química , Glutatión/metabolismo , Oro/química , Células Hep G2 , Humanos , Concentración de Iones de Hidrógeno , Concentración 50 Inhibidora , Cinética , Células MCF-7 , Nanopartículas del Metal/ultraestructura , Metacrilatos/química , Micelas , Nylons/química , Poliésteres/química , Nanomedicina Teranóstica/métodos
12.
Acta Biomater ; 48: 378-389, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27989922

RESUMEN

Co-delivery of antigen-encoding plasmid DNA (pDNA) and immune-modulatory molecules has importance in advancing gene-based immunotherapy and vaccines. Here novel star polymer nanocarriers were synthesized for co-delivery of pDNA and imiquimod (IMQ), a poorly soluble small-molecule adjuvant, to dendritic cells. Computational modeling and experimental results revealed that the polymers formed either multimolecular or unimolecular core-shell-type micelles in water, depending on the nature of the outer hydrophilic shell. Micelles loaded with both IMQ and pDNA were able to release IMQ in response to intracellular pH of the endo-lysosome and transfect mouse dendritic cells (DC2.4 line) in vitro. Importantly, IMQ-loaded micelle/pDNA complexes displayed much enhanced transfection efficiency than IMQ-free complexes. These results demonstrate the feasibility of co-delivery of pDNA and IMQ to antigen-presenting cells by multifunctional polymer nanocarriers with potential use in gene-based vaccine approaches.


Asunto(s)
Aminoquinolinas/administración & dosificación , ADN/administración & dosificación , Células Dendríticas/metabolismo , Sistemas de Liberación de Medicamentos , Técnicas de Transferencia de Gen , Plásmidos/administración & dosificación , Polímeros/química , Aminoquinolinas/farmacología , Animales , Muerte Celular , Línea Celular , Cromatografía en Gel , Células Dendríticas/efectos de los fármacos , Portadores de Fármacos/química , Liberación de Fármacos , Imiquimod , Cinética , Ratones , Micelas , Nanopartículas/química , Tamaño de la Partícula , Polímeros/síntesis química , Espectroscopía de Protones por Resonancia Magnética , Soluciones , Espectrofotometría Ultravioleta , Transfección , Agua/química
13.
Shanghai Kou Qiang Yi Xue ; 25(1): 38-41, 2016 Feb.
Artículo en Zh | MEDLINE | ID: mdl-27063306

RESUMEN

PURPOSE: To evaluate the effect of different acid etching modes on bond strength between composite resin and non-carious sclerotic dentin, and to provide references for clinical application. MOTHODS: Thirty premolars with naturally-occurring non-carious cervical lesions were divided into 2 groups based on self-etch adhesive system AdperTM Easy one (AEO) and total-etch adhesive system AdperTM Single Bond2 (ASB2). Each group was further divided into 3 subgroups (ASB21, ASB22, ASB23, AEO1, AEO2, AEO3) and subjected to the following processing: ASB21 subgroup was etched for 15 s with 35% phosphoric acid and coated with binder for 15 s; ASB22 subgroup was etched for 30 s with 35% phosphoric acid and coated with binder for 15 s; ASB23 subgroup was etched for 15 s with 35% phosphoric acid and coated with binder for 30 s; AEO1 subgroup was only etched with binder for 20 s; AEO2 subgroup was etched with binder for 40 s; AEO3 subgroup was etched for 15 s with 35% phosphoric acid and coated with binder for 20 s. The samples were restored with composite resin; 24 h after saved in distilled water at room temperature, the teeth were cut into dumbbell-shaped specimens with surface areas of approximately 1.0 mm2. The microtensile bond strength (µTBS) was detected and evaluated by one-way ANOVA and SNK-q test using SPSS 17.0 software package. RESULTS: µTBS was given in MPa: AEO3>ASB22>ASB23>ASB21>AEO2>AEO1, AEO3 resulted in statistically highest bond strength and AEO1 had the lowest bond strength (P<0.05), ASB22 acquired bond strength just lower than AEO3 (P<0.05). CONCLUSIONS: Use of total-etch adhesive system increasing the etching time of phosphoric time can enhance bond strength. For self-etch adhesive system,both duplicated the time of adhesive treatment and use of phosphoric acid can improve the bond strength. Use of phosphoric acid to etch for 15 s and coated with self-etch adhesive system for 20 s achieved the highest bond strength. In either self-etch or total-etch adhesive system, use of phosphoric acid to etch for 15 s and coated with self-etch adhesive system for 20 s achieved optimal bond strength, there was the lowest bond strength when the self-etch adhesive system used as recommended time.


Asunto(s)
Grabado Ácido Dental/métodos , Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Adhesivos , Resinas Compuestas , Dentina , Ensayo de Materiales , Ácidos Fosfóricos , Propiedades de Superficie , Resistencia a la Tracción
14.
Shanghai Kou Qiang Yi Xue ; 25(1): 32-7, 2016 Feb.
Artículo en Zh | MEDLINE | ID: mdl-27063305

RESUMEN

PURPOSE: To compare the effect of calcium hydroxide in different position on pH and inflammation factor expression of periapical osteoblasts. METHODS: 140 sterilized single-rooted human teeth models were randomly divided into 6 experiment groups and one control group: Group 1-3:calcium hydroxide paste was placed in the apical half of root canal, the upper half of root canal and the pulp champer; Group 4-6:Apexcal was placed in the apical half of root canal, the upper half of root canal and the pulp champer; Group 7: the control group without medication. 10 teeth of each group were placed in P.e suspension, the IL-6 and TNF-α expression of MC3T3-E1 was tested at 3 d and 7 d. The other teeth of each group were placed in distilled water, and the pH in periapical region was tested at 3, 7, 14 and 21 d. SPSS 13.0 software package was used for statistical analysis. RESULTS: Calcium hydroxide placed in different position of the root canal increased periapical pH value and reached its peak at 14 d. The group in which calcium hydroxide paste was placed in pulp chamber gained lower pH level than other experimental groups. IL-6, TNF-α expression of MC3T3-E1 pretreated by P.e suspension of experimental groups was significantly reduced compared with control group, and there was no significant difference between the experimental groups. CONCLUSIONS: Calcium hydroxide placed in different position of the root canal could increase periapical pH value and reduce IL- 6, TNF-α expression of periapical osteoblasts.


Asunto(s)
Hidróxido de Calcio/farmacología , Interleucina-6/metabolismo , Osteoblastos/metabolismo , Tejido Periapical/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Pulpa Dental , Cavidad Pulpar , Humanos , Materiales de Obturación del Conducto Radicular , Tratamiento del Conducto Radicular , Raíz del Diente
15.
J Biomater Appl ; 29(9): 1203-17, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25391445

RESUMEN

Non-classical ionomer glasses like those based on zinc-boron-germanium glasses are of special interest in a variety of medical applications owning to their unique combination of properties and potential therapeutic efficacy. These features may be of particular benefit with respect to the utilization of glass ionomer cements for minimally invasive dental applications such as the atruamatic restorative treatment, but also for expanded clinical applications in orthopedics and oral-maxillofacial surgery. A unique system of zinc-boron-germanium-based glasses (10 compositions in total) has been designed using a Design of Mixtures methodology. In the first instance, ionomer glasses were examined via differential thermal analysis, X-ray diffraction, and (11)B MAS NMR spectroscopy to establish fundamental composition - structure-property relationships for the unique system. Secondly, cements were synthesized based on each glass and handling characteristics (working time, Wt, and setting time, St) and compression strength were quantified to facilitate the development of both experimental and mathematical composition-structure-property relationships for the new ionomer cements. The novel glass ionomer cements were found to provide Wt, St, and compression strength in the range of 48-132 s, 206-602 s, and 16-36 MPa, respectively, depending on the ZnO/GeO2 mol fraction of the glass phase. A lower ZnO mol fraction in the glass phase provides higher glass transition temperature, higher N4 rate, and in combination with careful modulation of GeO2 mol fraction in the glass phase provides a unique approach to extending the Wt and St of glass ionomer cement without compromising (in fact enhancing) compression strength. The data presented in this work provide valuable information for the formulation of alternative glass ionomer cements for applications within and beyond the dental clinic, especially where conventional approaches to modulating working time and strength exhibit co-dependencies (i.e. the enhancement of one property comes at the expense of the other) and therefore limit development strategies.


Asunto(s)
Cementos de Ionómero Vítreo/química , Fenómenos Biomecánicos , Boro/química , Fuerza Compresiva , Germanio/química , Humanos , Espectroscopía de Resonancia Magnética , Ensayo de Materiales , Análisis de Regresión , Termodinámica , Difracción de Rayos X , Zinc/química
16.
Int J Biol Macromol ; 72: 855-61, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25301699

RESUMEN

A mechanochemical approach to improve the dispersion and the degree of crosslinking between cellulose fiber and polymer matrix is presented herein to create high performance poly(vinyl alcohol) (PVA)/cellulose biocomposites in a solvent-free and catalyst-free system. During a pan-milling process, the hydrogen bonds in both cellulose and PVA were effectively broken up, and the released hydroxyl groups could react with succinic anhydride (SA) to form covalent bonds between the two components. This stress-induced chemical reaction was verified by fourier transform infrared spectroscopy. The reaction kinetics was discussed according to the conversion rate of SA during the pan-milling process. Soxhlet extraction with hot water showed that the crosslinked PVA/cellulose retained more PVA in the composites due to the homogeneous and heterogeneous crosslinking. Scanning electron microscope images indicated the dispersion and interfacial interactions between PVA and cellulose were largely improved. The resulting composites exhibited remarkably enhanced mechanical properties. The tensile strength increased from 8.8 MPa (without mechanochemical treatment) to 18.2 MPa, and elongation at break increased from 76.8 to 361.7% after the treatment. Their thermal stability was also significantly improved.


Asunto(s)
Celulosa/química , Alcohol Polivinílico/química , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Termodinámica , Termogravimetría
17.
Carbohydr Polym ; 133: 493-6, 2015 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-26344306

RESUMEN

Water striders can walk on water. To mimic this function, a porous membrane consisted of bamboo cellulose fiber was hybridized with Ag/Ag2O nanoparticles through a facile in situ method to produce water repellent and well-ventilated materials. Herein, we report the sole surface roughness created by Ag/Ag2O nanoparticles could render the membrane a water contact angle (CA) of 140±3.0°. When floating on water, the hybrid membrane was able to support a heavy load more than 10 times the weight of the membrane itself. Additionally, this membrane demonstrated capabilities for oil sampling under water or oil/water separation and strong antibacterial activity against Escherichia coli. Thus we foresee that this novel hybrid membrane can be potentially utilized as drag-reducing, gas permeable and antibiotic substrates for constructing miniature aquatic devices.


Asunto(s)
Materiales Biomiméticos/química , Celulosa/química , Interacciones Hidrofóbicas e Hidrofílicas , Óxidos/química , Navíos , Compuestos de Plata/química , Plata/química , Agua/química , Antibacterianos/química , Antibacterianos/farmacología , Materiales Biomiméticos/farmacología , Escherichia coli/efectos de los fármacos , Membranas Artificiales , Poaceae/química
18.
ACS Appl Mater Interfaces ; 7(4): 2607-15, 2015 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-25562313

RESUMEN

Aerogels from polyethylenimine-grafted cellulose nanofibrils (CNFs-PEI) were developed for the first time as a novel drug delivery system. The morphology and structure of the CNFs before and after chemical modification were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Water-soluble sodium salicylate (NaSA) was used as a model drug for the investigation of drug loading and release performance. The CNFs-PEI aerogels exhibited a high drug loading capability (287.39 mg/g), and the drug adsorption process could be well described by Langmuir isotherm and pseudo-second-order kinetics models. Drug release experiments demonstrated a sustained and controlled release behavior of the aerogels highly dependent on pH and temperature. This process followed quite well the pseudo-second-order release kinetics. Owing to the unique pH- and temperature-responsiveness together with their excellent biodegradability and biocompatibility, the CNFs-PEI aerogels were very promising as a new generation of controlled drug delivery carriers, offering simple and safe alternatives to the conventional systems from synthetic polymers.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Celulosa/análogos & derivados , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/instrumentación , Nanofibras/química , Polietileneimina/análogos & derivados , Salicilato de Sodio/química , Antiinflamatorios no Esteroideos/farmacología , Celulosa/química , Geles/química , Cinética , Polietileneimina/química , Salicilato de Sodio/farmacología
19.
ACS Appl Mater Interfaces ; 7(7): 4336-43, 2015 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-25643170

RESUMEN

Oily wastewater is always a threat to biological and human safety, and it is a worldwide challenge to solve the problem of disposing of it. The development of interface science brings hope of solving this serious problem, however. Inspired by the capacity for capturing water of natural fabrics and by the underwater superoleophobic self-cleaning property of fish scales, a strategy is proposed to design and fabricate micro/nanoscale hierarchical-structured fabric membranes with superhydrophilicity and underwater superoleophobicity, by coating scaly titanium oxide nanostructures onto fabric microstructures, which can separate oil/water mixtures efficiently. The microstructures of the fabrics are beneficial for achieving high water-holding capacity of the membranes. More importantly, the special scaly titanium oxide nanostructures are critical for achieving the desired superwetting property toward water of the membranes, which means that air bubbles cannot exist on them in water and there is ultralow underwater-oil adhesion. The cooperative effects of the microscale and nanoscale structures result in the formation of a stable oil/water/solid triphase interface with a robust underwater superoleophobic self-cleaning property. Furthermore, the fabrics are common, commercially cheap, and environmentally friendly materials with flexible but robust mechanical properties, which make the fabric membranes a good candidate for oil/water separation even under strong water flow. This work would also be helpful for developing new underwater superoleophobic self-cleaning materials and related devices.


Asunto(s)
Polímeros/clasificación , Aguas Residuales/química , Purificación del Agua/instrumentación , Interacciones Hidrofóbicas e Hidrofílicas , Aceites/química , Polímeros/síntesis química , Polímeros/química , Textiles/análisis , Titanio/química , Purificación del Agua/métodos
20.
J Biomed Nanotechnol ; 11(8): 1401-17, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26295141

RESUMEN

In this study, a dual-ligand polymer-lipid hybrid nanoparticle drug delivery vehicle comprised of an anti-HER2/neu peptide (AHNP) mimic with a modified HIV-1 Tat (mTAT) was established for the targeted treatment of Her2/neu-overexpressing cells. The resultant dual-ligand hybrid nanoparticles (NPs) consisted of a poly(lactide-co-glycolide) core, a near 90% surface coverage of the lipid monolayer, and a 5.7 nm hydrated polyethylene glycol shell. Ligand density optimization study revealed that cellular uptake efficiency of the hybrid NPs could be manipulated by controlling the surface-ligand densities. Furthermore, the cell uptake kinetics and mechanism studies showed that the dual-ligand modifications of hybrid NPs altered the cellular uptake pathway from caveolae-mediated endocytosis (CvME) to the multiple endocytic pathways, which would significantly enhance the NP internalization. Upon the systemic investigation of the cellular uptake behavior of dual-ligand hybrid NPs, docetaxel (DTX), a hydrophobic anticancer drug, was successfully encapsulated into dual-ligand hybrid NPs with high drug loading for Her2/neu-overexpressing SK-BR-3 breast cancer cell treatment. The DTX-loaded dual-ligand hybrid NPs showed a decreased burst release and a more gradual sustained drug release property. Because of the synergistic effect of dual-ligand modification, DTX-loaded dual-ligand hybrid NPs exerted substantially better therapeutic potency against SK-BR-3 cancer cells than other NP formulations and free DTX drugs. These results demonstrate that the dual-ligand hybrid NPs could be a promising vehicle for targeted drug delivery to treat breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Nanocápsulas/química , Receptor ErbB-2/metabolismo , Taxoides/administración & dosificación , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/farmacocinética , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Neoplasias de la Mama/patología , Línea Celular Tumoral , Difusión , Docetaxel , Humanos , Ligandos , Lípidos/química , Nanocápsulas/ultraestructura , Polímeros/química , Taxoides/química , Resultado del Tratamiento , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/química
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