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1.
Gut Liver ; 17(4): 558-565, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-36510773

RESUMEN

Background/Aims: Among several methods used to prevent endoscopic submucosal dissection (ESD) bleeding, the recently developed hemostatic powder (HP) has few technical limitations and is relatively easy-to-use. This study aimed to analyze the hemostatic effects and mechanisms of two HPs using a porcine upper gastrointestinal hemorrhage model. Methods: We evaluated HPs (Endospray and epidermal growth factor [EGF]-endospray) for adhesion, waterproofing ability, permeability, and absorption in vitro. ESD was performed to induce bleeding ulcers in the porcine stomachs. In a total of three pigs, three bleeding ulcers per animal were generated. Hemostasis and rebleeding were evaluated endoscopically. After 72 hours, the animals were sacrificed, and histologically analyzed. Results: The water absorption of HPs was over 20 times the initial value within 30 minutes. The gelated HPs completely blocked water penetration into the applied site within 5 minutes and strongly adhered to the Petri-dish surface for up to 6 hours. The initial hemostasis rates within 5 minutes were 33.3%, 100.0%, and 66.7%, and the rebleeding rates at 6 to 72 hours after HP application were 33.3%, 16.7%, and 33.3% (control, Endospray, and EGF-endospray groups, respectively). Histological analysis revealed the thickness of the regenerated mucosa (522.1, 514.5, and 680.3 µm) and the submucosal layer (1,510.3, 2,848.2, and 3,062.3 µm) and the number of newly formed blood vessels (15.3, 17.9, and 20.5) in the control, Endospray, and EGF-endospray groups, respectively. Conclusions: The endoscopic HPs demonstrated the ability to elicit effective initial hemostasis and the histological ulcer-healing effect of EGF in an animal model of hemorrhagic gastric ulcers.


Asunto(s)
Resección Endoscópica de la Mucosa , Hemostáticos , Porcinos , Animales , Hemostáticos/farmacología , Factor de Crecimiento Epidérmico , Polvos , Úlcera , Mucosa Gástrica/cirugía , Hemostasis
2.
Mater Sci Eng C Mater Biol Appl ; 97: 55-66, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30678941

RESUMEN

The chronic kidney disease (CKD) patients are undergoing continuous ambulatory peritoneal dialysis (CAPD). However, there are some constraints, the frequent exchange of the dialysate and limitation of outside activity, associated with CAPD remain to be solved. In this study, we designed the wearable artificial kidney (WAK) system for peritoneal dialysis (PD) using urease-immobilized silk fibroin (SF) membrane and polymer-based spherical carbonaceous adsorbent (PSCA). We evaluated this kit's removal abilities of uremic toxins such as urea, creatinine, uric acid, phosphorus, and ß2-microglobulin from the dialysate of end-stage renal disease (ESRD) patients in vitro. The uremic toxins including urea, creatinine, uric acid, and phosphorus were removed about 99% by immobilized SF membrane and PSCA filter after 24 h treatment. However, only 50% of ß2-microglobulin was removed by this filtering system after 24 h treatment. In vivo study result shows that our filtering system has more uremic toxins removal efficiency than exchanged dialysate at every 6 h. We suggest that recirculating PD system using urease-immobilized SF membrane with PSCA could be more efficient than traditional dialysate exchange system for a WAK for PD.


Asunto(s)
Membranas Artificiales , Diálisis Peritoneal Ambulatoria Continua/instrumentación , Ureasa/química , Lesión Renal Aguda/terapia , Animales , Enzimas Inmovilizadas/química , Diseño de Equipo , Fibroínas/química , Filtración/instrumentación , Fallo Renal Crónico/terapia , Masculino , Microscopía Electrónica de Rastreo , Diálisis Peritoneal Ambulatoria Continua/métodos , Fósforo/aislamiento & purificación , Ratas Sprague-Dawley , Espectroscopía Infrarroja por Transformada de Fourier , Toxinas Biológicas/química , Microglobulina beta-2/aislamiento & purificación
3.
Sensors (Basel) ; 18(8)2018 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-30096902

RESUMEN

In this study, a portable urea sensor that monitors the urea concentration in flow conditions was fabricated. We propose an electrochemical sensor that continually measures the urea concentration of samples flowing through it at a constant flow rate in real time. For the electrochemical sensing, a porous silk fibroin membrane with immobilized urease was mounted in a polydimethylsiloxane (PDMS) sensor housing. The fabricated urea sensor elicited linear current⁻concentration characteristics in the clinically significant concentration range (0.1⁻20 mM) based on peritoneal dialysis. The sensor maintained the linear current⁻concentration characteristics during operation in flow conditions.


Asunto(s)
Técnicas Biosensibles , Reología , Urea/análisis , Técnicas Electroquímicas , Enzimas Inmovilizadas/metabolismo , Fibroínas , Porosidad , Seda , Factores de Tiempo , Ureasa/metabolismo
4.
Tissue Eng Regen Med ; 14(3): 233-241, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30603480

RESUMEN

We investigated the utility of the duck-feet collagen extraction patching procedure in the traumatic tympanic membrane (TM) perforation via a comparison with spontaneous healing or paper patch. Fifty-six ears of adult male Sprague-Dawley rats, each weighing in the range of 250 to 300 g, were used for the animal studies. Sixteen rats had one-side ear in the control group and the opposite-side ear in the treated groups. The remaining twelve rats had a one-side ear with the duck-feet collagen patch and the opposite-side ear with a paper patch. The proliferating cell nuclear antigen (PCNA) expression cells were calculated among the 200 basal cells, and the expression percentage was identified as the labeling index. The healing of the perforation in the duck-feet collagen patch group was confirmed to be more rapid compared to the healing of the other groups. PCNA staining was observed in the migrating portion of PCNA enhanced cell to collagen scaffold in Post operative day (POD) 7 of collagen patch group. Thus, the adhesive effect of the duck-feet collagen patch to perforated margin was better than that of the paper patch. After completing the healing process, the collagen patch shrank and detached from the tympanic membrane (POD 14). In this study, we confirmed that the use of a duck-feet collagen patch had the advantage of early healing, inducing natural TM contour, and disappearing ability after the patch effect is complete.

5.
J Biomed Mater Res B Appl Biomater ; 105(7): 2136-2144, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-27417290

RESUMEN

During the last decade, there has been a great advance in the kidney dialysis system by wearable artificial kidney (WAK) system for end-stage renal disease patients. Uremic solute removal and water regeneration system are the most prerequisite for WAK to work properly. In this study, we designed a filtering membrane system by using immobilized urease silk fibroin filter and evaluated its comparative effectiveness with a PVDF filtering system in peritoneal dialysate regeneration system by urea removal efficacy. We evaluated this membrane's characteristic and performances by conducting SEM-EDX analyze, water-binding abilities and porosity test, removal abilities of urea, cytotoxicity assay and enzyme activity assay. Under the condition for optimization of urease, the percentage removal of urea was about 40% and 60% in 50 mg/dL urea solution by urease immobilized PVDF and silk fibroin scaffolds, respectively. The batch experimental result showed that immobilized filter removed more than 50% of urea in 50 mg/dL urea solution. In addition silk fibroin with urease filter removed 90 percent of urea in the peritoneal dialysate after 24 h filtration. We suggest that silk fibroin with urease fixation filter can be used more effectively for peritoneal dialysate regeneration system, which have hydrophilic property and prolonged enzyme activity. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2136-2144, 2017.


Asunto(s)
Enzimas Inmovilizadas/química , Fibroínas/química , Ensayo de Materiales , Diálisis Peritoneal/instrumentación , Ureasa/química , Animales , Ratones , Células 3T3 NIH
6.
Mater Sci Eng C Mater Biol Appl ; 68: 758-767, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27524077

RESUMEN

Ideal dermal substitutes should have comparable physicochemical and biological properties to the natural skin tissue. In this study, we report a novel strategy to "engineer" controlled 3D nanocomposite fibrous matrix of poly(ε-caprolactone) (PCL) and silk fibroin (SF) for an artificial dermis application. Using a custom-designed cold-plate electrospinning and automatic magnet agitation system, up to 6mm of the thickness was achieved resulting from the accumulation of ice crystal layers on the PCL nanofibers surface-modified with the SF particles. The sacrificed ice crystals induced interconnected macro-pores ranging from tens to hundreds µm. The agitation system introduced uniform distribution of the SF protein within/on the nanofibers, preventing the particles from precipitation and agglomeration. NIH 3T3 fibroblasts proliferated in vitro on the PCL and PCL/SF scaffolds for 7days, but there was no statistical difference between the groups. Conversely, In vivo rat model studies revealed that the wound healing rate and collagen deposition increased with the SF content within the nanocomposites. The unique 3D construct with the PCL/SF nanocomposite fibers provided desirable spatial cues, surface topography, and surface chemistry for the native cells to infiltrate into the scaffolds. The wound healing potential of the nanocomposites was comparable to the commercial Matriderm® artificial dermis.


Asunto(s)
Fibroínas , Ensayo de Materiales , Nanocompuestos/química , Nanofibras/química , Poliésteres , Piel Artificial , Cicatrización de Heridas , Heridas y Lesiones/terapia , Animales , Fibroínas/química , Fibroínas/farmacología , Masculino , Ratones , Células 3T3 NIH , Poliésteres/química , Poliésteres/farmacología , Ratas , Ratas Sprague-Dawley , Heridas y Lesiones/metabolismo , Heridas y Lesiones/patología
7.
Int J Biol Macromol ; 93(Pt B): 1567-1574, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27431792

RESUMEN

Tissue-engineered skin substitutes may offer an effective therapeutic option for the treatment of patients with skin damages. In this study, a novel three-dimensional (3D) scaffold composed of electrospun silk fibroin (SF) nanofiber was fabricated using electrospinning with the addition of NaCl crystals. It has well known that the electrospun SF nanofibers were excellent scaffold for tissue. However, it is generally difficult for cells to infiltrate the electrospun silk fibroin due to its small pore size. To resolve this problem, we dropped the NaCl crystals above the rotating collector, which become incorporated into the nanofibers. Three methods (freeze-drying, salt-leaching, and electrospinning with NaCl) for fabrication of SF scaffolds were compared to the difference of their characteristics using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), mechanical strength, porosity, swelling abilities, and cell proliferation. Additionally, using air-liquid culture system, keratinocytes were co-cultured with fibroblasts in each type of SF scaffolds to construct an artificial bilayer skin in vitro. In our experimental results, histologic findings in only electrospun SF scaffolds showed more proliferation of fibroblasts in deep layer and more differentiation of keratinocytes in superficial layer. The present study suggests that 3D electrospun SF scaffolds might be a suitable for skin tissue engineering.


Asunto(s)
Bombyx/química , Nanofibras/química , Andamios del Tejido/química , Animales , Adhesión Celular , Proliferación Celular , Supervivencia Celular , Técnicas Electroquímicas , Fibroblastos , Fibroínas , Humanos , Ratones , Células 3T3 NIH , Nanofibras/ultraestructura , Porosidad , Piel Artificial , Propiedades de Superficie , Ingeniería de Tejidos
8.
Laryngoscope ; 126(12): 2798-2803, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27297322

RESUMEN

OBJECTIVES/HYPOTHESIS: Silk fibroin patching has been used to repair acute tympanic membrane perforations. Here, we describe the advantages and outcomes of this technique for chronic tympanic membrane perforations. STUDY DESIGN: Individual cohort study. METHODS: Forty patients were enrolled; half underwent perichondrium myringoplasty, and the silk fibroin patch technique was applied in the remaining patients. We compared the closure, otorrhea, and complication rates; closure time; postoperative hearing gain; and patient satisfaction between the two groups. RESULTS: Demographic data (gender, site, age, duration, preoperative air-bone gap, and perforation size and location) were not significantly different between the two groups. The closure rates and times, complication rates, and postoperative hearing gains were also similar in both groups. The mean operative time, otorrhea rate, and complication rate were also significantly better in the silk fibroin patch group. The intraoperative dizziness scores were higher in the conventional perichondrium myringoplasty group. CONCLUSIONS: Success rates were similar for the silk fibroin patch technique and conventional perichondrium myringoplasty; however, patching was an easier, faster procedure. Our results suggest that the silk fibroin patch technique is a suitable treatment for chronic tympanic membrane perforation. LEVEL OF EVIDENCE: 2b Laryngoscope, 126:2798-2803, 2016.


Asunto(s)
Fibroínas , Miringoplastia/métodos , Prótesis e Implantes , Perforación de la Membrana Timpánica/cirugía , Adulto , Audiometría de Tonos Puros , Enfermedad Crónica , Estudios de Cohortes , Femenino , Fibroínas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Miringoplastia/efectos adversos , Satisfacción del Paciente , Complicaciones Posoperatorias , Prótesis e Implantes/efectos adversos , Perforación de la Membrana Timpánica/terapia
9.
J Biomed Mater Res A ; 104(7): 1779-87, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26999521

RESUMEN

Bio-ceramic is a biomaterial actively studied in the field of bone tissue engineering. But, only certain ceramic materials can resolve the corrosion problem and possess the biological affinity of conventional metal biomaterials. Therefore, the recent development of composites of hybrid composites and polymers has been widely studied. In this study, we aimed to select the best scaffold of silk fibroin and ß-TCP hybrid for bone tissue engineering. We fabricated three groups of scaffold such as SF (silk fibroin scaffold), GS (silk fibroin/small granule size of ß-TCP scaffold) and GM (silk fibroin/medium granule size of ß-TCP scaffold), and we compared the characteristics of each group. During characterization of the scaffold, we used scanning electron microscopy (SEM) and a Fourier transform infrared spectroscopy (FTIR) for structural analysis. We compared the physiological properties of the scaffold regarding the swelling ratio, water uptake and porosity. To evaluate the mechanical properties, we examined the compressive strength of the scaffold. During in vitro testing, we evaluated cell attachment and cell proliferation (CCK-8). Finally, we confirmed in vivo new bone regeneration from the implanted scaffolds using histological staining and micro-CT. From these evaluations, the fabricated scaffold demonstrated high porosity with good inter-pore connectivity, showed good biocompatibility and high compressive strength and modulus. In particular, the present study indicates that the GM scaffold using ß-TCP accelerates new bone regeneration of implanted scaffolds. Accordingly, our scaffold is expected to act a useful application in the field of bone tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1779-1787, 2016.


Asunto(s)
Huesos/fisiología , Fosfatos de Calcio/farmacología , Fibroínas/farmacología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Materiales Biocompatibles/farmacología , Huesos/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Masculino , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Porosidad , Ratas Sprague-Dawley , Cráneo/diagnóstico por imagen , Cráneo/efectos de los fármacos , Cráneo/patología , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química , Microtomografía por Rayos X
10.
Int J Biol Macromol ; 85: 29-39, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26718866

RESUMEN

Silk fibroin has recently become an important biomaterial for tissue engineering application. In this study, silk fibroin nanomatrix was fabricated by electrospinning and evaluated as wound dressing material in a burn rat model. The wound size reduction, histological examination, and the quantification of transforming growth factor TGF-ß1 and interleukin IL-1α, 6, and 10 were measured to evaluate the healing effects. The silk fibroin nanomatrix treatment exhibited effective performance in decreasing the wound size and epithelialization. Histological finding also revealed that the deposition of collagen in the dermis was organized by covering the wound area in the silk fibroin nanomatrix treated group. The expression level of pro-inflammatory cytokine (IL-1α) was significantly reduced in the injured skin following the silk fibroin nanomatrix treatment compared to the medical gauze (control) at 7 days after burn. Also, the expression level of TGF-ß1 in the wound treated with silk fibroin nanomatrix peaked 21-days post-treatment whereas expression level of TGF-ß1 was highest at day 7 in the gauze treated group. In conclusion, this data demonstrates that silk fibroin nanomatrix enhances the burn wound healing, suggesting it is a good candidate for burn wound treatment.


Asunto(s)
Quemaduras/patología , Quemaduras/terapia , Fibroínas/química , Nanofibras/química , Seda/química , Cicatrización de Heridas , Animales , Materiales Biocompatibles/química , Colágeno/metabolismo , Modelos Animales de Enfermedad , Masculino , Nanofibras/ultraestructura , Ratas , Piel/metabolismo , Piel/patología , Ingeniería de Tejidos
11.
Int J Biol Macromol ; 85: 442-50, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26748068

RESUMEN

Collagen constituting the extracellular matrix has been widely used as biocompatible material for human use. In this study, we have selected duck's feet for extracting collagen. A simple method not utilizing harsh chemical had been employed to extract collagen from duck's feet. We fabricated duck's feet collagen/silk hybrid scaffold for the purpose of modifying the degradation rate of duck's feet collagen. This study suggests that extracted collagen from duck's feet is biocompatible and resembles collagen extracted from porcine which is commercially used. Duck's feet collagen is also economically feasible and it could therefore be a good candidate as a tissue engineering material. Further, addition of silk to fabricate a duck's feet collagen/silk hybrid scaffold could enhance the biostability of duck's feet collagen scaffold. Duck's feet collagen/silk scaffold increased the cell viability compared to silk alone. Animal studies also showed that duck's feet collagen/silk scaffold was more biocompatible than silk alone and more biostable than duck's feet or porcine collagen alone. Additionally, the results revealed that duck's feet collagen/silk hybrid scaffold had high porosity, cell infiltration and proliferation. We suggest that duck's feet collagen/silk hybrid scaffold could be used as a dermal substitution for full thickness skin defects.


Asunto(s)
Materiales Biocompatibles/química , Colágeno/química , Seda/química , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Adhesión Celular , Línea Celular , Supervivencia Celular , Patos , Fibroínas/química , Masculino , Ratones , Porosidad , Ratas , Sincalida/química , Espectroscopía Infrarroja por Transformada de Fourier , Ingeniería de Tejidos/métodos
12.
Int J Biol Macromol ; 82: 160-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26257379

RESUMEN

The present study demonstrated the fabrication that incorporation of titanium isopropoxide (TiO2) and hydroxyapatite (HA) nanoparticles into the silk fibroin (SF) scaffolds. In this process, we prepared TiO2 nanoparticles using sol-gel synthesis and the porous structure was developed by salt-leaching process. Homogeneous distribution of TiO2 and HA nanoparticles were confirmed by images of VP-FE-SEM and those equipped with energy dispersive X-ray spectrometer. Structural characteristics of the porous SF/TiO2/HA hybrid scaffold were also determined using FTIR analysis and X-ray diffractometer. In this study, the porous SF/TiO2/HA hybrid scaffold showed similar porosity, enhanced mechanical property, but decreased water binding abilities, compared with the porous SF scaffold. For evaluation of the osteogenic differentiation of rat bone marrow mesenchymal stem cells, alkaline phosphatase activity and osteogenic gene expression were employed. Our results revealed that the porous SF/TiO2/HA hybrid scaffold had improved osteoinductivity compared with the porous SF scaffold. These results suggest that the osteogenic property as well as mechanical property of the porous SF/TiO2/HA hybrid scaffold could be better than the porous SF scaffold. Therefore, the porous SF/TiO2/HA hybrid scaffold may be a good promising biomaterial for bone tissue engineering application.


Asunto(s)
Materiales Biocompatibles/química , Durapatita/química , Fibroínas/química , Seda/química , Ingeniería de Tejidos , Andamios del Tejido/química , Titanio/química , Animales , Huesos , Adhesión Celular , Diferenciación Celular , Proliferación Celular , Ensayo de Materiales , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Nanopartículas/química , Nanopartículas/ultraestructura , Osteogénesis , Ratas , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
13.
J Tissue Eng Regen Med ; 10(3): 209-21, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25628059

RESUMEN

Porous silk scaffolds, which are considered to be natural polymers, cannot be used alone because they have a long degradation rate, which makes it difficult for them to be replaced by the surrounding tissue. Scaffolds composed of synthetic polymers, such as PLGA, have a short degradation rate, lack hydrophilicity and their release of toxic by-products makes them difficult to use. The present investigations aimed to study hybrid scaffolds fabricated from PLGA, silk and hydroxyapatite nanoparticles (Hap NPs) for optimized bone tissue engineering. The results from variable-pressure field emission scanning electron microscopy (VP-FE-SEM), equipped with EDS, confirmed that the fabricated scaffolds had a porous architecture, and the location of each component present in the scaffolds was examined. Contact angle measurements confirmed that the introduction of silk and HAp NPs helped to change the hydrophobic nature of PLGA to hydrophilic, which is the main constraint for PLGA used as a biomaterial. Thermo-gravimetric analysis (TGA) and FT-IR spectroscopy confirmed thermal decomposition and different vibrations caused in functional groups of compounds used to fabricate the scaffolds, which reflected improvement in their mechanical properties. After culturing osteoblasts for 1, 7 and 14 days in the presence of scaffolds, their viability was checked by MTT assay. The fluorescent microscopy results revealed that the introduction of silk and HAp NPs had a favourable impact on the infiltration of osteoblasts. In vivo experiments were conducted by implanting scaffolds in rat calvariae for 4 weeks. Histological examinations and micro-CT scans from these experiments revealed beneficial attributes offered by silk fibroin and HAp NPs to PLGA-based scaffolds for bone induction.


Asunto(s)
Huesos/fisiología , Ácido Láctico/farmacología , Ácido Poliglicólico/farmacología , Seda/farmacología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Huesos/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Durapatita/química , Masculino , Microscopía Electrónica de Rastreo , Nanopartículas/química , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Presión , Ratas Sprague-Dawley , Cráneo/efectos de los fármacos , Cráneo/patología , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
14.
J Biomed Mater Res B Appl Biomater ; 104(3): 508-14, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25939800

RESUMEN

Films prepared from silk fibroin have shown potential as biomaterials in tissue engineering applications for the eye. Here, we present a novel process for fabrication of silk fibroin films for corneal application. In this work, fabrication of silk fibroin films was simply achieved by centrifugal force. In contrast to the conventional dry casting method, we carried out the new process in a centrifuge with a rotating speed of 4000 rpm, where centrifugal force was imposed on an aluminum tube containing silk fibroin solution. In the present study, we also compared the surface roughness, mechanical properties, transparency, and cell proliferation between centrifugal and dry casting method. In terms of surface morphology, films fabricated by the centrifugal casting have less surface roughness than those by the dry casting. For elasticity and transparency, silk fibroin films obtained from the centrifugal casting had favorable results compared with those prepared by dry casting. Furthermore, primary human corneal keratocytes grew better in films prepared by the centrifugal casting. Therefore, our results suggest that this new fabrication process for silk fibroin films offers important potential benefits for corneal tissue regeneration.


Asunto(s)
Córnea/metabolismo , Fibroínas/química , Queratinocitos/metabolismo , Ensayo de Materiales , Ingeniería de Tejidos , Células Cultivadas , Córnea/citología , Elasticidad , Humanos , Queratinocitos/citología
15.
Tissue Eng Regen Med ; 13(3): 218-226, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30603402

RESUMEN

Hydrocolloid dressings have been developed for many types of wound healing. In particular, dressing is a critical component in the successful recover of burn injuries, which causes a great number of people to not only suffer from physical but also psychological and economic anguish each year. Additionally, silk fibroin is the safest material for tissue engineering due to biocompatibility. In this study, we fabricated hydrocolloid dressings incorporating silk fibroin nanoparticles to enhance the efficacy of hydrocolloid dressing and then use this silk fibroin nanoparticle hydrocolloid dressing (SFNHD) in animal models to treat burn wounds. The structures and properties of SFNHD were characterized using tensile strength and Cell Counting Kit-8 assay. The results indicated the structural stability and the cellular biocompatibility of the hydrocolloid dressing suggesting that SFNHD can be applied to the treatment of wounds. To demonstrate the capacity of a silk fibroin hydrocolloid dressing to treat burn wounds, we compared SFNHD to gauze and Neoderm®, a commercially available dressing. This study clearly demonstrated accelerated wound healing with greater wound structural integrity and minimal wound size after treatment with SFNHD. These observations indicate that SFNHD may be an improvement upon current standard dressings such as Gauze and Neoderm® for burn wounds.

16.
Int J Biol Macromol ; 78: 215-23, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25849999

RESUMEN

Silk fibroin is a biomaterial being actively studied in the field of bone tissue engineering. In this study, we aimed to select the best strategy for bone reconstruction on scaffolds by changing various conditions. We compared the characteristics of each scaffold via structural analysis using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), the swelling ratio, water uptake, porosity, compressive strength, cell infiltration and cell viability (CCK-8). The scaffolds had high porosity with good inter pore connectivity and showed high compressive strength and modulus. In addition, to confirm bone reconstruction, animal studies were conducted in which samples were implanted in rat calvaria and investigated by micro-CT scans. In conclusion, the presented study indicates that using sucrose produces scaffolds showing better pore interconnectivity and cell infiltration than scaffolds made by using a salt process. In addition, in vivo experiments showed that hydroxyapatite accelerates bone reconstruction on implanted scaffolds. Accordingly, our scaffold will be expected to have a useful application in bone reconstruction.


Asunto(s)
Huesos , Sales (Química)/química , Seda/química , Sacarosa/química , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Materiales Biocompatibles/química , Técnicas de Cultivo de Célula , Durapatita/química , Fibroínas/química , Humanos , Masculino , Ensayo de Materiales , Células Madre Mesenquimatosas , Nanopartículas/química , Nanopartículas/ultraestructura , Porosidad , Ratas , Espectroscopía Infrarroja por Transformada de Fourier
17.
Nanomedicine ; 11(3): 681-91, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25555351

RESUMEN

Tissue-engineered skin substitutes such as nanofibers from traditional electrospinning may offer an effective therapeutic option for the treatment of patients suffering from skin damages such as burns and diabetic ulcers. However, it is generally difficult for cells to infiltrate the nanofibers due to their small pore size and sheets-like appearance. In the present study, a facile and efficient strategy has successfully been introduced that can produce 3D silk fibroin nanofibers, obviating an intrinsic limitation of traditional and salt-leaching electrospinning by introducing cold-plate electrospinning. The cell attachment and infiltration studies indicated the use of 3D nanofiber scaffolds by cold-plate electrospinning as a potential candidate to overcome intrinsic barriers of electrospinning techniques. The 3D nanofiber scaffolds using this technique presented a high porosity with controlled thickness and an easy contouring of facial shape; these properties can contribute to the ideal candidate for artificial skin reconstruction. From the clinical editor: Electrospun nanofibers are considered as promising scaffolds for tissue engineering due to extracellular matrix mimicking factor resulting in a controllable 3D nanofibrous form. The cold-plate electrospinning technique can facilitate the fabrication of these biomaterials to create structures that could resemble the dermis.


Asunto(s)
Fibroínas/química , Nanofibras/química , Piel Artificial
18.
J Biomed Nanotechnol ; 10(7): 1294-303, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24804550

RESUMEN

Several auto- or alloplastic dermal substitutes have been used for full thickness skin defects. However, there is no ideal dermal substitute that is biocompatible and offers adequate mechanical properties and sufficient thickness and volume. Silk fibroin can be considered a possible alternative material for the construction of dermal substitutes. Nanofibers fabricated by electrospinning silk fibroin were considered an excellent candidate due to their desirable biocompatibility. However, it is generally difficult for cells to infiltrate the electrospun silk fibroin due to its small pore size. To overcome this challenge, a key parameter is the control of the pore size of silk fibroin electrospun such that cells can easily infiltrate into the nanofibers and proliferate internally. In this work, a novel approach is introduced by dropping two different size NaCl crystals above the rotating collector, which become incorporated into the nanofibers. The structures and properties of the, resulting electrospun silk fibroin were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and its wound healing effect for a full thickness skin defect was compared with Matriderm. Although the dermal regenerative effect of the 3D-SF (3D electrospun silk fibroin nanofiber matrix) was similar to that of Matriderm, the 3D-SF was almost completely degraded and did not induce wound contracture like Matriderm. We suggest that 3D-SF can be applied to the treatment of full thickness skin defects.


Asunto(s)
Órganos Artificiales , Dermis/fisiología , Fibroínas/farmacología , Nanofibras/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Vendajes , Bombyx , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dermis/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Fibroblastos/ultraestructura , Masculino , Ratones , Células 3T3 NIH , Nanofibras/ultraestructura , Porosidad , Ratas , Ratas Sprague-Dawley , Espectroscopía Infrarroja por Transformada de Fourier , Coloración y Etiquetado , Agua/química , Cicatrización de Heridas/efectos de los fármacos
19.
Int J Biol Macromol ; 68: 158-68, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24794196

RESUMEN

The present study deals with fabrication of scaffolds composing of silk fibroin and TiO2 NPs fabricated using a salt-leaching process. At first instance, the TiO2 NPs were prepared by using sol-gel synthesis, affording to have average diameter of 77±21µm. Furthermore, the aqueous solutions of silk fibroin were mixed with 0.2%, 2.0% and 4.0% of TiO2 NPs and salt-leaching process was introduced which resulted in creation of porous scaffolds modified with TiO2 NPs. The presence of TiO2 NPs in scaffolds was confirmed by VP-FE-SEM-EDS, TGA and XRD. The presence of TiO2 NPs influenced in decrease in pore size and swelling behavior of composite scaffolds. The resultant mechanical property of scaffolds was improved upon the introduction of TiO2 NPs. Moreover, cell cytotoxicity results for 1, 3 and 7 days; revealed no toxic behavior to osteoblasts. However, a mild toxicity to NIH 3T3 fibroblasts was observed with the scaffolds containing 4.0% TiO2 NPs. The cell fixation results from 1 and 7 days of incubation indicated the attachment, spreading and subsequent proliferation of fibroblasts. However, these findings were independent to the amount of TiO2 NPs in scaffolds.


Asunto(s)
Fibroínas/farmacología , Nanopartículas/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Titanio/química , Animales , Adhesión Celular/efectos de los fármacos , Ratones , Células 3T3 NIH , Nanopartículas/ultraestructura , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Transición de Fase/efectos de los fármacos , Espectrometría por Rayos X , Termogravimetría , Agua/química , Difracción de Rayos X
20.
J Biomed Mater Res A ; 102(8): 2713-24, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24026912

RESUMEN

The present study deals with the fabrication of poly(lactic-co-glycolic acid) (PLGA) scaffolds modified with silk fibroin for biomedical application. The PLGA solutions were added with salt particles and pressed with high pressures; which were further subjected to salt leaching resulting in the creation of large sized pores in the PLGA scaffolds. To fill up these pores, 2%, 4%, and 8% of silk solutions were added, however, the addition created extra small sized pores. The scaffolds were characterized by various state of techniques; the scanning electronic microscopy revealed the large sized pores in the pristine scaffold can be tailored into smaller architecture by the addition of silk fibroin. The contact angle measurements confirmed the introduction of silk helped to change the hydrophobic nature of PLGA into hydrophilic, which is the main constrain for PLGA. The mechanical properties of scaffold can be easily improved by applying the higher amounts of silk into the scaffolds. The thermal gravimetric analyses and fourier transform infrared spectroscopy confirmed the presence of silk fibroin in scaffolds. The cell viability and cell attachment was checked by culturing the scaffolds with NIH 3T3 fibroblasts and chondrocytes. Furthermore, these results revealed that the introduction of silk had significant impact on the viability of fibroblast also had a good affinity for cell attachment and infiltration of human chondrocytes in scaffolds after culturing the cells for 2 and 5 weeks of time.


Asunto(s)
Fibroínas/química , Ácido Láctico/química , Ácido Poliglicólico/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Bombyx , Adhesión Celular , Supervivencia Celular , Condrocitos/citología , Condrocitos/ultraestructura , Fibroblastos/citología , Fibroblastos/ultraestructura , Humanos , Ratones , Microscopía Electrónica de Rastreo , Células 3T3 NIH , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Porosidad , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Estrés Mecánico , Termogravimetría
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