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ABSTRACT: This study presents an innovative surgery that successfully improved the facial profile and occlusal function of a patient with a skeletal Class III malocclusion and posterior hypodontia. The patient had chief complaints of missing teeth and a protrudedjaw. A novel 1-stage surgery referred to as posterior mandibular segmental split osteotomy combined with Le Fort i osteotomy and BSSRO was used because the patient wanted to save time and was worried about periodontal complications associated with other treatment methods. As a result, a satisfying facial profile and a Class I occlusion with a normal position of the posterior dentoalveolar segment of the mandible were achieved with no adverse effects. Thus, posterior mandibular segmental split osteotomy can be considered an effective treatment for skeletal Class III malocclusion with posterior hypodontia.
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Anodoncia , Maloclusión de Angle Clase III , Cefalometría/métodos , Humanos , Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Osteotomía Mandibular/métodos , Maxilar/cirugía , Osteotomía Le Fort/métodosRESUMEN
Dental pulp engineering possesses a promising perspective to replacing lost pulp in the root canal and restoring its functions. Stable adhesion of dental pulp stem cells (DPSCs) on the root canal dentin wall is a key element required for reconstruction of a functional odontoblast layer in dental pulp regeneration. To address this challenge, dopamine-modified hyaluronic acid (DA-HA) is coated on dentin to obtain a stable adhesion of DPSCs. The dopamine segment provides adhesion ability to the coating, and the hyaluronic acid increases the biocompatibility. The results show that DPSCs can adhere on the DA-HA coated dentin slice better than those without coating. Simultaneously, DPSCs proliferation can be further promoted on the prepared coating. Therefore, the DA-HA coating may provide a possible way to immobilize odontoblast cell onto dentin surface for pulp regeneration.
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Pulpa Dental , Células Madre , RegeneraciónRESUMEN
A sustained-release system was established by synthesis of dexamethasone-loaded hollow hydroxyapatite microspheres (DHHAM). The in vitro effect of DHHAM on odontogenic differentiation of human dental pulp cells (hDPCs) was evaluated. Hollow hydroxyapatite microspheres (HHAM) are successfully manufactured using simple biomimetic one-step strategy in the presence of glycine and sodium dodecyl sulfonate. Dexamethasone (DEX) was loaded to the system after the formation of HHAM. The drug encapsulation capacity of DEX in HHAM is 40.3% and its loading efficiency is 16.7%. The cumulative release of DEX in vitro is 55% up to 35 days. Results of Real-time Polymerase Chain Reaction (Real-time PCR), alkaline phosphatase (ALP) activity and Alizarin Red S staining revealed that DHHAM can obviously promote bio-mineralization of hDPCs in the absence of osteogenic medium and enhance the gene expression of ALP, Runt-related transcription factor 2 (RUNX2), osteocalcin, dentin sialophosphoprotein (DSPP) and dentin matrix protein 1 (DMP1). The data suggest that sustained release of DEX from DHHAM could efficiently enhance odontogenic differentiation of hDPCs.
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Pulpa Dental , Durapatita , Fosfatasa Alcalina , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Dexametasona , Proteínas de la Matriz Extracelular , Humanos , Microesferas , FosfoproteínasRESUMEN
BACKGROUND: Improving the posterior airway space is one of the most important functions of genioplasty. Studies have shown that the posterior airway space (PAS) can play an important role in the evaluation of obstructive sleep apnea syndrome (OSAS). The purpose of this study is to evaluate the airway safety of our modified technology by observing the impact on PAS in skeletal Class II patients without OSAS. METHODS: We have modified a cosmetic genioplasty, which can guarantee the continuity of the lower edge of the bilateral mandible by rotating the chin segment clockwise. Fourteen patients submitted to our modified cosmetic genioplasty alone were included in the study. The facial convexity angle and the ratio of the face were measured by analyzing photographs. The position of the hyoid bone and the width of the PAS were measured by analyzing lateral cephalograms. The volume and the cross-sectional area (CSA) of the PAS were measured using 3D reconstruction. The Wilcoxon signed-rank test and paired samples t test were used to assess the significance of differences of the data (p < 0.05). RESULTS: Soft tissue measurements were statistically different (p = 0.001) and achieved satisfactory results. The position of the hyoid bone moved up (LX: p = 0.004; LML: p = 0.056) and forward (LY: p = 0.001; LCV3: p = 0.016). The increase in the CSA had statistical significance (p < 0.005). There were significant statistical differences in the total airway volume and hypopharynx (p = 0.001), except in the oropharynx (p = 0.096). CONCLUSIONS: Our modified genioplasty not only achieved better cosmetic results by ensuring the continuity of the lower edge of the bilateral mandible but also exerted a significant positive impact on the posterior airway space for patients with skeletal class II, thus helping reduce the prevalence of OSAS. We hence suggest performing this modified cosmetic genioplasty on the skeletal class II patients with/without OSAS if necessary. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Mentoplastia , Hueso Hioides , Cefalometría , Mentón/cirugía , Humanos , Hueso Hioides/diagnóstico por imagen , Hueso Hioides/cirugía , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , RadiografíaRESUMEN
Sepsis, which is the most severe clinical manifestation of acute infection and has a mortality rate higher than that of cancer, represents a significant global public health burden. Persistent methicillin-resistant Staphylococcus aureus (MRSA) infection and further host immune paralysis are the leading causes of sepsis-associated death, but limited clinical interventions that target sepsis have failed to effectively restore immune homeostasis to enable complete eradication of MRSA. To restimulate anti-MRSA innate immunity, we developed CRV peptide-modified lipid nanoparticles (CRV/LNP-RNAs) for transient in situ programming of macrophages (MΦs). The CRV/LNP-RNAs enabled the delivery of MRSA-targeted chimeric antigen receptor (CAR) mRNA (SasA-CAR mRNA) and CASP11 (a key MRSA intracellular evasion target) siRNA to MΦs in situ, yielding CAR-MΦs with boosted bactericidal potency. Specifically, our results demonstrated that the engineered MΦs could efficiently phagocytose and digest MRSA intracellularly, preventing immune evasion by the "superbug" MRSA. Our findings highlight the potential of nanoparticle-enabled in vivo generation of CAR-MΦs as a therapeutic platform for multidrug-resistant (MDR) bacterial infections and should be confirmed in clinical trials.
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Liposomas , Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Receptores Quiméricos de Antígenos , Sepsis , Infecciones Estafilocócicas , Animales , Ratones , Receptores Quiméricos de Antígenos/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , ARN Mensajero , Antibacterianos/farmacología , Macrófagos , Sepsis/tratamiento farmacológico , Lípidos/farmacologíaRESUMEN
The most challenging problem in oral and maxillofacial surgery is the reconstruction of defects for the oral and maxillofacial complex. Transfer of different autografts is known as the "gold standard" for the reconstruction of bone defects in the oral and maxillofacial region. Graft harvesting, however, can lead to many complications, such as donor-site morbidity, surgical time-consuming, etc. Three-dimensional (3D) printing technology is an innovative technique that allows the fabrication of personalized plates and scaffolds to fit the precise anatomy of an individual's defect. In this study, a selective laser melting 3D-printed Ti-6Al-4 V plate with a honeycomb was designed, and its physical and biological features were characterized. The personalized 3D-printed scaffold and commercialized titanium reconstruction plate were applied to reconstruct a 4 cm mandibular defect in a beagle dog. Effects of the treatment were analyzed radiologically and histologically. Our results showed that the application of a 3D-printed plate with a honeycomb achieved good biocompatibility and osseointegration and has potential clinical application.
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Mandíbula , Titanio , Perros , Animales , Titanio/química , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Impresión Tridimensional , Rayos LáserRESUMEN
Human dental pulp stem cells (hDPSCs) have been a focus of pulp regeneration research because of their excellent odontogenic potential and availability. Applying the odontoblastic differentiation of hDPSCs to tooth regeneration has been challenging. Metformin-based carbon nanodots (MCDs) were synthesized and characterized to investigate their effects in vitro on odontoblastic hDPSC differentiation and the underlying mechanism. MCDs were synthesized by a hydrothermal treatment method and characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The biocompatibility and fluorescence properties of the MCDs in Dulbecco's modified Eagle's medium high-glucose culture medium and the in vitro odontogenic potential and related mechanism of the bioactive nanomaterial was explored. TEM images showed that MCDs were spherical in shape with a size of approximately 5.9 nm. MCDs showed biological safety in cell viability, apoptosis, and fluorescence labelling ability at a concentration up to 200 µg/ml in vitro. The presence of MCDs facilitated high-efficiency odontogenic differentiation of hDPSCs by promoting odontogenic gene and protein expression. Moreover, MCDs promoted odontoblastic hDPSC differentiation via autophagy. MCDs are capable of activating autophagy and enhancing the odontogenic differentiation of hDPSCs by upregulating odontoblast gene marker (DMP1, DSPP, RUNX2, and SP7) and protein (DSPP and DMP1) expression.
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Nanomaterial-based drug sustainable release systems have been tentatively applied to bone regeneration. They, however, still face disadvantages of high toxicity, low biocompatibility, and low drug-load capacity. In view of the low toxicity and high biocompatibility of polymer nanomaterials and the excellent load capacity of hollow nanomaterials with high specific surface area, we evaluated the hollow polydopamine nanoparticles (HPDA NPs), in order to find an optimal system to effectively deliver the osteogenic drugs to improve treatment of bone defect. Data demonstrated that the HPDA NPs synthesized herein could efficiently load four types of osteogenic drugs and the drugs can effectively release from the HPDA NPs for a relatively longer time in vitro and in vivo with low toxicity and high biocompatibility. Results of qRT-PCR, ALP, and alizarin red S staining showed that drugs released from the HPDA NPs could promote osteogenic differentiation and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs) in vitro. Image data from micro-CT and H&E staining showed that all four osteogenic drugs released from the HPDA NPs effectively promoted bone regeneration in the defect of tooth extraction fossa in vivo, especially tacrolimus. These results suggest that the HPDA NPs, the biodegradable hollow polymer nanoparticles with high drug load rate and sustainable release ability, have good prospect to treat the bone defect in future clinical practice.
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Nanopartículas , Preparaciones Farmacéuticas , Animales , Regeneración Ósea , Indoles , Osteogénesis , Polímeros , RatasRESUMEN
To develop effective implants for delivery of 3,4-dihydro-3-methyl-4-oxoimidazo[5,1-d]-as-tetrazine-8-carboxamide (temozolomide; TM) with low initial burst and less neurotoxicity, TM-loaded poly-propylene carbonate (PPC) fiber was fabricated by electrospinning. Some of the fiber sheets were then covered with alginate (ALG). Influences of several preparation parameters on drug delivery behavior were investigated. The micro-morphology of these fibers was studied using scanning electron microscopy and differential scanning calorimetry. In vitro release properties of two forms of samples were observed and their cytotoxicity against C6 glioma cells was assessed. Using strict preparation parameters, smooth and uniform fiber could only be obtained when the PPC concentration was 8 % by weight, at 20cm and a voltage of 15 kV between the nozzle and the collection instrument. Fiber diameter was about 3 microm. The initial burst of drug-fiber sheets was reduced after the fiber sheets were covered with ALG. Cytotoxicity test results suggested that both forms of drug fibers inhibit the C6 glioma cells continuously; the pure drug-fiber sheets were strongly cytotoxic. We conclude that (a) electrospinning is a reliable fabrication method for M-loaded PPC fibers; and (b) an ALG coating reduces the initial burst of the fiber sheets.
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Antineoplásicos Alquilantes/administración & dosificación , Antineoplásicos Alquilantes/farmacocinética , Dacarbazina/análogos & derivados , Glioma/metabolismo , Antineoplásicos Alquilantes/uso terapéutico , Rastreo Diferencial de Calorimetría , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dacarbazina/administración & dosificación , Dacarbazina/farmacocinética , Dacarbazina/uso terapéutico , Sistemas de Liberación de Medicamentos , Excipientes , Humanos , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Polipropilenos , Temozolomida , Sales de Tetrazolio , TiazolesRESUMEN
AIMS: Cancer stem cells (CSCs) are the source of tumors and play a key role in the resistance of cancer to therapies. To improve the current therapies against CSCs, in this work we developed a novel system of electrospun polycaprolactone (PCL) nanofibers containing hydroxylated multi-walled carbon nanotubes (MWCNTs-OH) and all-trans retinoic acid (ATRA). MATERIALS AND METHODS: The nanofiber membranes were forged by electrospinning, and the physical and chemical properties of the nanofiber membranes were evaluated by scanning electron microscopy, XRD and Raman etc. The photothermal properties of nanofiber membranes and their effects on CSCs differentiation and cytotoxicity were investigated. Finally, the anti-tumor effect of nanofiber membranes in vivo was evaluated. KEY FINDINGS: The nanofibers formed under optimal conditions were smooth without beads. The nanofibrous membranes with MWCNTs-OH could increase temperature of the medium under near-infrared (NIR) illumination to suppress the viability of glioma stem cells (GSCs). Meanwhile, the added ATRA could further induce the differentiation of GSCs to destroy their stemness and reduce their resistance to heat treatment. Compared with no NIR irradiation, after 2min NIR irradiation, the membranes reduced the in-vitro viability of GSCs by 13.41%, 14.83%, and 26.71% after 1, 2, and 3 days, respectively. After 3 min daily illumination for 3 days, the viability of GSCs was only 22.75%, and similar results were observed in vivo. SIGNIFICANCE: These results showed efficiently cytotoxicity to CSCs by combining heat therapy and differentiation therapy. The nanofiber membranes if inserted at the site after surgical tumor removal, may hinder tumor recurrence.
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Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/terapia , Glioma/terapia , Nanofibras/uso terapéutico , Células Madre Neoplásicas/efectos de los fármacos , Tretinoina/uso terapéutico , Animales , Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Glioma/patología , Humanos , Hipertermia Inducida/métodos , Masculino , Ratones Endogámicos BALB C , Nanofibras/química , Nanotubos de Carbono/química , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Células Madre Neoplásicas/patología , Poliésteres/química , Poliésteres/uso terapéutico , Tretinoina/administración & dosificaciónRESUMEN
Tubular dentin is of great significance in the process of tooth tissue and tooth regeneration, because it is not only the structural feature of primary dentin, but also can affect the tooth sensory function, affect the differentiation of dental pulp cells and provide strong mechanical support for teeth. Scaffold is one of the three elements of tissue engineering dentin regeneration. Most experiments on dentin regeneration involve the study of the microstructure and mechanical properties of the scaffold. The microstructure and mechanical characteristics of scaffold materials have important effects on the differentiation and adhesion of odontoblast, it can directly affect the tissue structure of regenerated dentin.
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Pulpa Dental , Andamios del Tejido , Diferenciación Celular , Dentina , Odontoblastos , Regeneración , Ingeniería de TejidosRESUMEN
PURPOSE: To evaluate the effects of simvastatin in a new injectable microsphere hydrogel system on bone healing process of tooth sockets. MATERIALS AND METHODS: Simvastatin was loaded in poly (lactic-co-glycolic acid) (PLGA) microspheres using an emulsion process, and the drug-loaded PLGA microspheres were further entrapped in a gelatin hydrogel to form an injectable microsphere-hydrogel system. Simvastatin-free hydrogel and blank microspheres hydrogel were used as controls. A rat tooth extraction socket model was generated, and the simvastatin-loaded microsphere-hydrogel composite was injected in the defect area of a tooth socket. At 1, 2, 5, and 8 weeks after the surgery, all the animals were sacrificed and the mandibles were harvested. The samples were examined using X-ray, hematoxylin and eosin staining, and histological evaluations. RESULTS: Five weeks after the surgery, significantly more bone tissue was formed in the simvastatin-loaded hydrogel group than in the simvastatin-free hydrogel group and the blank microspheres hydrogel group as control (p < 0.05). CONCLUSION: The injectable simvastatin-loaded microsphere hydrogel promoted new bone formation in the tooth extraction socket after 5 weeks, and has a promising potential for bone repair and regeneration.
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Osteogénesis , Animales , Hidrogeles , Ácido Láctico , Microesferas , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Simvastatina , Alveolo DentalRESUMEN
Formation of tertiary dentin to maintain pulp vitality is a major odontoblastic response to dental pulp injury. Human bone morphogenetic protein 2 (hBMP2) can promote proliferation and differentiation of odontoblasts. Current study is interested in evaluating if the hBMP2 can promote the regeneration of tertiary dentin and cure dental pulp injury using the adenoviral vector to deliver hBMP2 cDNA into the pulp. Primary culture of dental pulp cells of exfoliated deciduous teeth (hDPCs) was established. Human serotype 5 adenoviral vector, AdCMV-hBMP2, was created. AdCMV-hBMP2 was used to transduce hDPCs in vitro and dental pulp cells in animal model in vivo. Data clearly demonstrated that hBMP2 increased ALP and mineralization. Reverse transcription-real time quantitative PCR (RT-QPCR) data showed that hBMP2 dramatically increased gene expressions of Runx2 (Runt-related transcription factor 2), ALP, Col Iα (Collagen 1a1), SP7 (Osterix), DMP1 (dentin matrix acidic phosphoprotein 1), DSPP (dentin sialophosphoprotein), and BSP (bonesialoprotein), which are normally involved in osteogenesis/odontogenesis. Data from in vivo assays demonstrated that hBMP2 promoted pulp cell proliferation and increased formation of tertiary dentin in dental pulp. Our in vitro and in vivo data suggest that hBMP2 gene can efficiently be delivered into the dental pulp cells by adenovirus, and show potential clinical application for the treatment of dental pulp damage.
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Rapamycin, a mammalian target of rapamycin inhibitor and anti-proliferative agent, is used to treat glioma and other malignancies, but its effectiveness is limited by the fact that it cannot be delivered in a targeted manner to the site of the tumor. To address this issue, we fabricated a mesh via electrospinning using two biodegradable materials, poly(lactic acid) (PLA) and polyethylene oxide (PEO) as a carrier for rapamycin delivery to the tumor. Nanofiber diameter decreased with increasing PLA concentration in the mixed solution. Scanning electron microscopy analysis revealed the smooth and uniform surface morphology of hybrid fibers. Fourier transform infrared spectroscopy analysis demonstrated that rapamycin was encapsulated in the polymer solution; encapsulation efficiency was high and stable over the range of drug concentrations from 0.5-2wt%. A correlation was observed between sustained release of the drug in vitro and cytotoxicity in cultured glioma cells. These results indicate that the PEO/poly(d,l-lactic acid) nanofiber mesh can be used as a targeted delivery system for rapamycin that can limit side effects and prevent locoregional recurrence following surgical resection of glioma.
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Sistemas de Liberación de Medicamentos/métodos , Glioblastoma , Lactatos/química , Nanofibras/química , Polietilenglicoles/química , Sirolimus/química , Línea Celular Tumoral , Liberación de Fármacos , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Humanos , Lactatos/administración & dosificación , Lactatos/metabolismo , Nanofibras/administración & dosificación , Polietilenglicoles/administración & dosificación , Polietilenglicoles/metabolismo , Sirolimus/administración & dosificación , Sirolimus/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Resultado del Tratamiento , Difracción de Rayos XRESUMEN
It is a challenge for dentists to save dental pulp in patients with pulp disease without resorting to root canal therapy. Formation of tertiary dentin to maintain pulp vitality is a key odontoblast response to dental pulp injury. Vascular endothelial growth factor (VEGF) is the most potent angiogenic and vasculogenic factor involved in tertiary dentin formation. It was hypothesized that VEGF may be used to treat pulp diseases such as pulpitis. To explore this hypothesis, the first step was to assess whether VEGF affects dental pulp cells to promote reparative dentin formation. In the current study, an AdCMVhVEGF vector was constructed to deliver hVEGF into dental pulp cells of exfoliated deciduous teeth (hDPCs) in vitro and dental pulp cells in a rat model in vivo. The collected data clearly demonstrated that hVEGF increased alkaline phosphatase and mineralization by enzymatic activity. RTqPCR data demonstrated that hVEGF significantly increased the expression levels of genes commonly involved in osteogenesis/odontogenesis. Data from the in vivo assays indicated that hVEGF enhanced pulp cell proliferation and neovascularization, and markedly increased formation of reparative dentin in dental pulp. The in vitro and in vivo data suggest that hVEGF may have potential clinical applications, thus may aid in the development of novel treatment strategies for dental pulpitis.
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Dentina/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Calcificación Fisiológica/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Niño , Pulpa Dental/citología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratas Wistar , Diente Primario/citologíaRESUMEN
Electrospun poly(ε-caprolactone) (PCL)/gelatin (GT) scaffolds were developed to provide controlled release of 7-ethyl-10-hydroxy camptothecin (SN-38). Acetic acid was introduced to improve the miscibility of PCL and GT to produce a homogeneous nanofiber membrane mixture. The effect of SN-38 content in binary mixtures on processability, fiber morphology, water sorption, swelling, and drug release was investigated. Electrospun PCL/GT blend nonwoven fibers showed fiber surface roughness, decreased PCL crystallinity, and increased swelling with increasing drug content of 1, 2, and 4 wt %. Additionally, increasing the SN-38 concentration reduced the degradation rate of the GT. Furthermore, we hypothesize the existence of a drug content saturation point in the monoaxial fiber to explain the different drug release patterns of PG2 compared with those of PG1 and PG4. The matrix also showed good biodegradation and anti-tumor function. Our results demonstrate that SN-38-loaded PCL/GT fibers can be obtained by electrospinning. The SN-38-loaded fibers merit further evaluation as a means to potentially prevent locoregional recurrence following surgical tumor resection.
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Antineoplásicos/farmacología , Materiales Biocompatibles/química , Camptotecina/análogos & derivados , Gelatina/química , Glioblastoma/tratamiento farmacológico , Nanofibras/química , Poliésteres/química , Antineoplásicos/química , Camptotecina/química , Camptotecina/farmacología , Línea Celular Tumoral , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacología , Liberación de Fármacos , Humanos , Irinotecán , Membranas/metabolismo , Ingeniería de Tejidos/métodos , Andamios del TejidoRESUMEN
Regeneration of large bone defects is a common clinical problem. Recently, stem cell sheet has been an emerging strategy in bone tissue engineering. To enhance the osteogenic potential of stem cell sheet, we fabricated bone morphogenetic protein 2 (BMP-2) gene-engineered cell sheet using a complex of polyethylenimine-alginate (PEI-al) nanocomposites plus human BMP-2 complementary(c)DNA plasmid, and studied its osteogenesis in vitro and in vivo. PEI-al nanocomposites carrying BMP-2 gene could efficiently transfect bone marrow mesenchymal stem cells. The cell sheet was made by culturing the cells in medium containing vitamin C for 10 days. Assays on the cell culture showed that the genetically engineered cells released the BMP-2 for at least 14 days. The expression of osteogenesis-related gene was increased, which demonstrated that released BMP-2 could effectively induce the cell sheet osteogenic differentiation in vitro. To further test the osteogenic potential of the cell sheet in vivo, enhanced green fluorescent protein or BMP-2-producing cell sheets were treated on the cranial bone defects. The results indicated that the BMP-2-producing cell sheet group was more efficient than other groups in promoting bone formation in the defect area. Our results suggested that PEI-al nanocomposites efficiently deliver the BMP-2 gene to bone marrow mesenchymal stem cells and that BMP-2 gene-engineered cell sheet is an effective way for promoting bone regeneration.
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Alginatos/química , Proteína Morfogenética Ósea 2/genética , Trasplante de Células Madre Mesenquimatosas/instrumentación , Células Madre Mesenquimatosas/fisiología , Polietileneimina/química , Fracturas Craneales/terapia , Andamios del Tejido , Animales , Proteína Morfogenética Ósea 2/metabolismo , Sustitutos de Huesos/síntesis química , Diseño de Equipo , Análisis de Falla de Equipo , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Masculino , Nanocompuestos/química , Nanocompuestos/ultraestructura , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Ratas , Ratas Wistar , Fracturas Craneales/diagnóstico , Ingeniería de Tejidos/instrumentación , Resultado del TratamientoRESUMEN
This study describes the use of poly(propylene carbonate) (PPC) electrospun fibers as vehicle for the sustained delivery of dibutyryl cyclic adenosine monophosphate (dbcAMP) to the hemisected spinal cord. The dbcAMP and PPC were uniformly mixed with acetonitrile; then, electrospinning was used to generate micron fibers. The release of dbcAMP was assessed by ELISA in vitro. Our results showed that the encapsulation of dbcAMP in the fibers led to stable and prolonged release in vitro. The PPC micron fibers containing dbcAMP and the PPC micron fibers without dbcAMP were then implanted into the hemisected thoracic spinal cord, followed by testing of the functional recovery and immunohistochemistry. Compared with the control group, sustained delivery of dbcAMP promoted axonal regenerative sprouting and functional recovery and reduced glial scar formation, and the PPC micron fibers without dbcAMP did not have these effects. Our findings demonstrated the feasibility of using PPC electrospun fibers containing dbcAMP for spinal cord injury. The approach described here also will provide a platform for the potential delivery of other axon-growth-promoting or scar-inhibiting agents.