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1.
BMC Musculoskelet Disord ; 24(1): 908, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996830

RESUMO

BACKGROUND: The ramifications of osteoporotic fractures and their subsequent complications are becoming progressively detrimental for the elderly population. This study evaluates the clinical ramifications of postoperative bone cement distribution in patients with osteoporotic vertebral compression fractures (OVCF) who underwent both bilateral and unilateral Percutaneous Vertebroplasty (PVP). OBJECTIVE: The research aims to discern the influence of bone cement distribution on the clinical outcomes of both bilateral and unilateral Percutaneous Vertebroplasty. The overarching intention is to foster efficacious preventive and therapeutic strategies to mitigate postoperative vertebral fractures and thereby enhance surgical outcomes. METHODS: A comprehensive evaluation was undertaken on 139 patients who received either bilateral or unilateral PVP in our institution between January 2018 and March 2022. These patients were systematically classified into three distinct groups: unilateral PVP (n = 87), bilateral PVP with a connected modality (n = 29), and bilateral PVP with a disconnected modality (n = 23). Several operational metrics were juxtaposed across these cohorts, encapsulating operative duration, aggregate hospital expenses, bone cement administration metrics, VAS (Visual Analogue Scale) scores, ODI (Oswestry Disability Index) scores relative to lumbar discomfort, postoperative vertebral height restitution rates, and the status of the traumatized and adjacent vertebral bodies. Preliminary findings indicated that the VAS scores for the January and December cohorts were considerably reduced compared to the unilateral PVP group (P = 0.015, 0.032). Furthermore, the recurrence of fractures in the affected and adjacent vertebral structures was more pronounced in the unilateral PVP cohort compared to the bilateral PVP cohorts. The duration of the procedure (P = 0.000) and the overall hospitalization expenses for the unilateral PVP group were markedly lesser than for both the connected and disconnected bilateral PVP groups, a difference that was statistically significant (P = 0.015, P = 0.024, respectively). Nevertheless, other parameters, such as the volume of cement infused, incidence of cement spillage, ODI scores for lumbar discomfort, post-surgical vertebral height restitution rate, localized vertebral kyphosis, and the alignment of cement and endplate, did not exhibit significant statistical deviations (P > 0.05). CONCLUSION: In juxtaposition with unilateral PVP, the employment of bilateral PVP exhibits enhanced long-term prognostic outcomes for patients afflicted with vertebral compression fractures. Notably, bilateral PVP significantly curtails the prevalence of subsequent vertebral injuries. Conversely, the unilateral PVP cohort is distinguished by its abbreviated operational duration, minimal invasiveness, and reduced overall hospitalization expenditures, conferring it with substantial clinical applicability and merit.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Idoso , Vertebroplastia/efeitos adversos , Vertebroplastia/métodos , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/cirurgia , Fraturas por Compressão/complicações , Cimentos Ósseos/uso terapêutico , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/etiologia , Resultado do Tratamento , Cifoplastia/métodos , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Fraturas por Osteoporose/complicações , Estudos Retrospectivos
2.
Int J Mol Sci ; 22(23)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34884641

RESUMO

Fibroblasts in the synovial membrane secrete molecules essential to forming the extracellular matrix (ECM) and supporting joint homeostasis. While evidence suggests that fibroblasts contribute to the response to joint injury, the outcomes appear to be patient-specific and dependent on interactions between resident immune cells, particularly macrophages (Mφs). On the other hand, the response of Mφs to injury depends on their functional phenotype. The goal of these studies was to further explore these issues in an in vitro 3D microtissue model that simulates a pathophysiological disease-specific microenvironment. Two sources of fibroblasts were used to assess patient-specific influences: mesenchymal stem cell (MSC)- and induced pluripotent stem cell (iPSC)-derived fibroblasts. These were co-cultured with either M1 or M2 Mφs, and the cultures were challenged with polyethylene particles coated with lipopolysaccharide (cPE) to model wear debris generated from total joint arthroplasties. Our results indicated that the fibroblast response to cPE was dependent on the source of the fibroblasts and the presence of M1 or M2 Mφs: the fibroblast response as measured by gene expression changes was amplified by the presence of M2 Mφs. These results demonstrate that the immune system modulates the function of fibroblasts; furthermore, different sources of differentiated fibroblasts may lead to divergent results. Overall, our research suggests that M2 Mφs may be a critical target for the clinical treatment of cPE induced fibrosis.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Polietileno/farmacologia , Artroplastia/métodos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Matriz Extracelular , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Fibroblastos/metabolismo , Fibrose/tratamento farmacológico , Fibrose/imunologia , Fibrose/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Células-Tronco Mesenquimais/imunologia
3.
Scand J Gastroenterol ; 48(2): 213-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23234601

RESUMO

BACKGROUND: Currently, there is no consensus on the recommendation of peginterferon alfa (pegIFNα) to chronic hepatitis B (CHB) patients with poor viral response (EVR). This study aimed to assess the sustained curative efficacy of adefovir (ADV) add-on therapy in optimizing pegIFNα monotherapy. METHODS: A total of 85 hepatitis B e antigen (HBeAg)-positive CHB patients with poor virological response at month 6 after starting pegIFNα-2a were enrolled, and received either pegIFNα-2a continuing monotherapy (group A, n = 51) or add-on therapy with ADV (group B, n = 34). The treatment duration for all patients was 6 months, and the sustained responses after the end of treatment were evaluated between two groups. RESULTS: The baseline characteristics were comparable between two groups. At months 6 after treatment completion, the sustained virological response (SVR) rates were 31.4% and 73.5%, the sustained biochemical response (SBR) rates were 39.2% and 85.3% in group A and group B respectively, and the difference in either SVR or SBR was statistically significant (both p < 0.001). As compared to patients in group A, significantly more patients in group B obtained HBeAg loss (19.6% vs. 55.9%, p = 0.001) and seroconversion (13.7% vs. 41.2%, p = 0.004). CONCLUSION: ADV add-on therapy could significantly improve and sustain the curative efficacy of CHB patient with poor virological response to pegIFNα-2a monotherapy, but further large well-designed randomized controlled trials are needed to confirm our findings.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Organofosfonatos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adenina/uso terapêutico , Adulto , Biomarcadores/sangue , Esquema de Medicação , Quimioterapia Combinada , Feminino , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento , Carga Viral
4.
Nanotechnology ; 24(10): 105102, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23425941

RESUMO

Graphene oxide (GO) has attracted intensive interest in the biomedical field in recent years. We investigate whether the use of functional graphene oxide as an efficient delivery system for delivering specific molecular antitumor therapeutics in vivo could achieve a more excellent antitumor effect. Constitutive activation of signal transducer and activator of transcription 3 (Stat3) promotes survival in a wide spectrum of human cancers. In this paper, we study the in vivo behavior of graphene oxide chemically functionalized with polyethylenimine and polyethylene glycol (GO-PEI-PEG) as a plasmid-based Stat3-specific small interfering RNA (siRNA) carrier in mouse malignant melanoma. The in vivo results indicate significant regression in tumor growth and tumor weight after plasmid-based Stat3 siRNA delivered by GO-PEI-PEG treatment. Moreover, there was no significant side effect from GO-PEI-PEG treatment according to histological examination and blood chemistry analysis in mice. Thus, our work is the first success of using GO-PEI-PEG as a promising carrier for plasmid Stat3 siRNA delivery and down-regulation of Stat3 by a polymer-mediated vehicle and suggests the great promise of graphene in biomedical applications such as cancer treatment.


Assuntos
Terapia Genética/métodos , Grafite/química , Melanoma/patologia , Nanotecnologia/métodos , Óxidos/química , Plasmídeos/metabolismo , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Citometria de Fluxo , Melanoma/terapia , Melanoma Experimental , Camundongos , Nanoestruturas/química , Transplante de Neoplasias , Neoplasias/terapia , Polietilenoglicóis/química , Polietilenoimina/química , Transfecção
5.
Biomed Mater ; 16(1): 012002, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-32906098

RESUMO

Mesenchymal stem cell-derived extracellular matrix (mECM) has received increased attention in the fields of tissue engineering and scaffold-assisted regeneration. mECM exhibits many unique characteristics, such as robust bioactivity, biocompatibility, ease of use, and the potential for autologous tissue engineering. As the use of mECM has increased in musculoskeletal tissue engineering, it should be noted that mECM generated from current methods has inherited insufficiencies, such as low mechanical properties and lack of internal architecture. In this review, we first summarize the development and use of mECM as a scaffold for musculoskeletal tissue regeneration and highlight our current progress on moving this technology toward clinical application. Then we review recent methods to improve the properties of mECM that will overcome current weaknesses. Lastly, we propose future studies that will pave the road for mECM application in regenerating tissues in humans.


Assuntos
Matriz Extracelular/fisiologia , Células-Tronco Mesenquimais/fisiologia , Sistema Musculoesquelético/lesões , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Regeneração Óssea , Cartilagem/lesões , Cartilagem/fisiologia , Células Cultivadas , Matriz Extracelular/química , Humanos , Teste de Materiais , Transplante de Células-Tronco Mesenquimais , Fenômenos Fisiológicos Musculoesqueléticos , Regeneração/fisiologia
6.
Acta Biomater ; 105: 44-55, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32035282

RESUMO

Damaged articular cartilage has limited self-healing capabilities, leading to degeneration that affects millions of people. Although cartilage tissue engineering is considered a promising approach for treatment, robust and long-term chondrogenesis within a 3-dimensional (3D) scaffold remains a major challenge for complete regeneration. Most current approaches involve incorporation of transforming growth factor-ß (TGF-ß) into the scaffold, but have limited utility owing to the short functional half-life and/or rapid clearance of TGF-ß. In this study, we have tested the incorporation of graphene oxide nanosheets (GO) within a photopolymerizable poly-D, l-lactic acid/polyethylene glycol (PDLLA) hydrogel, for its applicability in sustained release of the chondroinductive growth factor TGF-ß3. We found that with GO incorporation, the hydrogel scaffold (GO/PDLLA) exhibited enhanced initial mechanical strength, i.e., increased compressive modulus, and supported long-term, sustained release of TGF-ß3 for up to 4 weeks. In addition, human bone marrow-derived mesenchymal stem cells (hBMSCs) seeded within TGF-ß3 loaded GO/PDLLA hydrogels displayed high cell viability and improved chondrogenesis in a TGF-ß3 concentration-dependent manner. hBMSCs cultured in GO/PDLLA also demonstrated significantly higher chondrogenic gene expression, including aggrecan, collagen type II and SOX9, and cartilage matrix production when compared to cultures maintained in GO-free scaffolds containing equivalent amounts of TGF-ß3. Upon subcutaneous implantation in vivo, hBMSC-seeded TGF-ß3-GO/PDLLA hydrogel constructs displayed considerably greater cartilage matrix than their TGF-ß3/PDLLA counterparts without GO. Taken together, these findings support the potential application of GO in optimizing TGF-ß3 induced hBMSC chondrogenesis for cartilage tissue engineering. STATEMENT OF SIGNIFICANCE: In this work, we have developed a graphene oxide (GO) incorporated, photocrosslinked PDLLA hybrid hydrogel for localized delivery and sustained release of loaded TGF-ß3 to seeded cells. The incorporation of GO in PDLLA hydrogel suppressed the burst release of TGF-ß3, and significantly prolonged the retention time of the TGF-ß3 initially loaded in the hydrogel. Additionally, the GO improved the initial compressive strength of the hydrogel. Both in vitro analyses and in vivo implantation results showed that the GO/PDLLA constructs seeded with human mesenchymal stem cells (hMSCs) showed significantly higher cartilage formation, compared to GO-free scaffolds containing equivalent amount of TGF-ß3. Findings from this work suggest the potential application of the GO-TGF/PDLLA hydrogel as a functional scaffold for hMSC-based cartilage tissue engineering.


Assuntos
Diferenciação Celular , Condrogênese , Grafite/química , Hidrogéis/química , Células-Tronco Mesenquimais/citologia , Fator de Crescimento Transformador beta3/farmacologia , Animais , Cartilagem/metabolismo , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Preparações de Ação Retardada/farmacologia , Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos SCID , Poliésteres/química , Tela Subcutânea/efeitos dos fármacos
7.
Biomaterials ; 29(9): 1189-97, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18083224

RESUMO

Demineralized bone matrix (DBM) is a collagen-based scaffold, but its low mechanical strength and limited BMP-2 binding ability restrict its application in bone repair. It is known that heparin could be immobilized onto scaffolds to enhance their binding of growth factors with the heparin-binding domain. Here, we crosslinked heparin to DBM to increase its BMP-2 binding ability. To our surprise, the mechanical strength of DBM was also dramatically increased. The compression modulus of heparin crosslinked DBM (HC-DBM) have improved (seven-fold increased) under wet condition, which would allow the scaffolds to keep specific shapes in vivo. As expected, HC-DBM showed specific binding ability to BMP-2. Additional studies showed the bound BMP-2 exerted its function to induce cell differentiation on the scaffold. Subcutaneous implantation of HC-DBM carrying BMP-2 showed higher alkaline phosphatase (ALP) activity (2 weeks), more calcium deposition (4 and 8 weeks) and more bone formation than that of control groups. It is concluded that HC-DBM has increased mechanical intensity as well as specific BMP-2 binding ability; HC-DBM/BMP-2 enhances the osteogenesis and therefore could be an effective medical device for bone repair.


Assuntos
Matriz Óssea/química , Matriz Óssea/fisiologia , Proteínas Morfogenéticas Ósseas/metabolismo , Substitutos Ósseos/química , Heparina/química , Fator de Crescimento Transformador beta/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Matriz Óssea/efeitos dos fármacos , Matriz Óssea/ultraestrutura , Proteína Morfogenética Óssea 2 , Cálcio/metabolismo , Bovinos , Reagentes de Ligações Cruzadas , Heparina/farmacologia , Humanos , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteogênese , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual
8.
Biomaterials ; 28(21): 3198-207, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17434580

RESUMO

The physiological role of cumulus cell surrounding oocytes is particularly important for normal cytoplasmic maturation of oocytes. Collagen-based demineralized bone matrix (DBM) is a valuable biomaterial for the three-dimensional (3-D) cell culture. The present study was designed to determine whether in vitro maturation (IVM) of cumulus-free oocytes in mice could be improved by using the 3-D DBM co-culture system. The results indicated that the denuded oocytes cultured in 3-D DBM co-culture system with cumulus cells showed close similarity of cortical granules (CGs) distribution pattern, had more normal maturation-promoting factor (MPF) level and zona pellucida (ZP) hardening level to the in vivo matured oocytes, and the best preimplantation development after being activated by in vitro fertilization (IVF) or parthenogenetic activation. Thus, 3-D DBM collagen scaffold could serve as a tool for fundamental in vitro studies of cells or tissues under the environment that closely assembles the in vivo conditions.


Assuntos
Matriz Óssea/química , Técnicas de Cocultura/métodos , Colágeno/química , Oócitos/fisiologia , Animais , Materiais Biocompatíveis/química , Técnica de Desmineralização Óssea/métodos , Matriz Óssea/ultraestrutura , Bovinos , Células Cultivadas , Cromossomos de Mamíferos/metabolismo , Colágeno/metabolismo , Grânulos Citoplasmáticos/metabolismo , Feminino , Fertilização in vitro , Fibroblastos/citologia , Fibroblastos/metabolismo , Formazans/análise , Fator Promotor de Maturação/análise , Meiose/fisiologia , Mesotelina , Camundongos , Oócitos/citologia , Ovário/citologia , Partenogênese/efeitos dos fármacos , Partenogênese/fisiologia , Porosidade , Estrôncio/farmacologia , Sais de Tetrazólio/análise , Zona Pelúcida/fisiologia
9.
Biomaterials ; 28(6): 1027-35, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17095085

RESUMO

Considerable research has been focused on the development of bone morphogenetic protein-2 (BMP-2) delivery system for homologous and efficient bone regeneration. The aim of the present study was to develop a collagen-based targeting bone repair system. A collagen-binding domain (CBD) was added to the N-terminal of native BMP-2 to allow it bind to collagen specifically. We showed that the collagen-binding bone morphogenetic protein-2 (named bone morphogenetic protein2-h, BMP2-h) had maintained the full biological activity as compared to rhBMP2 lacking the CBD. In vitro functional study also demonstrated that collagen matrix could maintain higher bioactivity of BMP2-h than native BMP-2. When demineralized bone matrix (DBM) impregnated with BMP2-h was implanted subcutaneously in rats, homogeneous bone formation was observed. Moreover, in a rabbit mandible defect model, surgical implantation of collagen matrix loaded with BMP2-h exhibited remarkable osteoinductive properties and excellent homogeneous bone formation. Our studies suggested that this novel collagen-based BMP-2 targeting bone repair system induced better bone formation not only in quantity but also in quality. Similar approaches may also be used for the repair of other tissue injuries.


Assuntos
Matriz Óssea/química , Proteínas Morfogenéticas Ósseas/administração & dosagem , Proteínas Morfogenéticas Ósseas/química , Regeneração Óssea/efeitos dos fármacos , Colágeno/metabolismo , Fraturas Mandibulares/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Fator de Crescimento Transformador beta/administração & dosagem , Fator de Crescimento Transformador beta/química , Animais , Técnica de Desmineralização Óssea , Proteína Morfogenética Óssea 7 , Proteínas Morfogenéticas Ósseas/farmacocinética , Portadores de Fármacos/química , Consolidação da Fratura/efeitos dos fármacos , Masculino , Fraturas Mandibulares/patologia , Coelhos , Ratos , Ratos Wistar , Fator de Crescimento Transformador beta/farmacocinética , Resultado do Tratamento
10.
Acta Biomater ; 58: 302-311, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28611002

RESUMO

Three-dimensional hydrogel constructs incorporated with live stem cells that support chondrogenic differentiation and maintenance offer a promising regenerative route towards addressing the limited self-repair capabilities of articular cartilage. In particular, hydrogel scaffolds that augment chondrogenesis and recapitulate the native physical properties of cartilage, such as compressive strength, can potentially be applied in point-of-care procedures. We report here the synthesis of two new materials, [poly-l-lactic acid/polyethylene glycol/poly-l-lactic acid] (PLLA-PEG 1000) and [poly-d,l-lactic acid/polyethylene glycol/poly-d,l-lactic acid] (PDLLA-PEG 1000), that are biodegradable, biocompatible (>80% viability post fabrication), and possess high, physiologically relevant mechanical strength (∼1500 to 1800kPa). This study examined the effects of physiologically relevant cell densities (4, 8, 20, and 50×106/mL) and hydrogel stiffnesses (∼150kPa to∼1500kPa Young's moduli) on chondrogenesis of human bone marrow stem cells incorporated in hydrogel constructs fabricated with these materials and a previously characterized PDLLA-PEG 4000. Results showed that 20×106cells/mL, under a static culture condition, was the most efficient cell seeding density for extracellular matrix (ECM) production on the basis of hydroxyproline and glycosaminoglycan content. Interestingly, material stiffness did not significantly affect chondrogenesis, but rather material concentration was correlated to chondrogenesis with increasing levels at lower concentrations based on ECM production, chondrogenic gene expression, and histological analysis. These findings establish optimal cell densities for chondrogenesis within three-dimensional cell-incorporated hydrogels, inform hydrogel material development for cartilage tissue engineering, and demonstrate the efficacy and potential utility of PDLLA-PEG 1000 for point-of-care treatment of cartilage defects. STATEMENT OF SIGNIFICANCE: Engineering cartilage with physiologically relevant mechanical properties for point-of-care applications represents a major challenge in orthopedics, given the generally low mechanical strengths of traditional hydrogels used in cartilage tissue engineering. In this study, we characterized a new material that possesses high mechanical strength similar to native cartilage, and determined the optimal cell density and scaffold stiffness to achieve the most efficient chondrogenic response from seeded human bone marrow stem cells. Results show robust chondrogenesis and strongly suggest the potential of this material to be applied clinically for point-of-care repair of cartilage defects.


Assuntos
Células da Medula Óssea/metabolismo , Condrogênese , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , Poliésteres/química , Polietilenoglicóis/química , Células da Medula Óssea/citologia , Cartilagem/citologia , Cartilagem/metabolismo , Técnicas de Cultura de Células , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia
11.
J Biomed Mater Res A ; 79(3): 591-8, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16817216

RESUMO

Spinal cord injury (SCI) creates an adverse environment for axon regeneration. As a result, the axons at the injury sites begin to be atrophy, retract and lose their functions. Several strategies to promote axon regeneration at the injury site have been tested, but the progress is very limited. One of the major reasons is that the regenerated axons often extend randomly and do not reach the proper place. Fabricating linearly ordered materials as nerve guidance would be important to solve such problems. In this study, a novel type of nerve guidance material was prepared from the bovine aponeurosis, which mainly consisted of ordered collagen fibers. The processed material showed good cell compatibility and low immunogenisity. Moreover, the processed material guided the neurites outgrowth of in vitro cultured cortical neurons along its fibers. The results suggested that the processed aponeurosis would be a proper nerve guidance biomaterial for SCI repair.


Assuntos
Regeneração Nervosa , Traumatismos da Medula Espinal/patologia , Animais , Materiais Biocompatíveis/uso terapêutico , Bovinos , Adesão Celular , Colágeno/metabolismo , Colágeno/uso terapêutico , Colágeno/ultraestrutura , Microscopia Eletrônica de Varredura , Regeneração Nervosa/efeitos dos fármacos , Neuritos , Traumatismos da Medula Espinal/dietoterapia
12.
Acta Biomater ; 35: 68-76, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26945631

RESUMO

Regeneration of injured tendon and ligament (T&L) remains a clinical challenge due to their poor intrinsic healing capacity. Tissue engineering provides a promising alternative treatment approach to facilitate T&L healing and regeneration. Successful tendon tissue engineering requires the use of three-dimensional (3D) biomimetic scaffolds that possess the physical and biochemical features of native tendon tissue. We report here the development and characterization of a novel composite scaffold fabricated by co-electrospinning of poly-ε-caprolactone (PCL) and methacrylated gelatin (mGLT). We found that photocrosslinking retained mGLT, resulted in a uniform distribution of mGLT throughout the depth of scaffold and also preserved scaffold mechanical strength. Moreover, photocrosslinking was able to integrate stacked scaffold sheets to form multilayered constructs that mimic the structure of native tendon tissues. Importantly, cells impregnated into the constructs remained responsive to topographical cues and exogenous tenogenic factors, such as TGF-ß3. The excellent biocompatibility and highly integrated structure of the scaffold developed in this study will allow the creation of a more advanced tendon graft that possesses the architecture and cell phenotype of native tendon tissues. STATEMENT OF SIGNIFICANCE: The clinical challenges in tendon repair have spurred the development of tendon tissue engineering approaches to create functional tissue replacements. In this study, we have developed a novel composite scaffold as a tendon graft consisting of aligned poly-ε-caprolactone (PCL) microfibers and methacrylated gelatin (mGLT). Cell seeding and photocrosslinking between scaffold layers can be performed simultaneously to create cell impregnated multilayered constructs. This cell-scaffold construct combines the advantages of PCL nanofibrous scaffolds and photocrosslinked gelatin hydrogels to mimic the structure, mechanical anisotropy, and cell phenotype of native tendon tissue. The scaffold engineered here as a building block for multilayer constructs should have applications beyond tendon tissue engineering in the fabrication of tissue grafts that consist of both fibrous and hydrogel components.


Assuntos
Gelatina/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Poliésteres/farmacologia , Tendões/fisiologia , Engenharia Tecidual/métodos , Tecido Adiposo/citologia , Adulto , Reagentes de Ligações Cruzadas/farmacologia , Feminino , Humanos , Luz , Masculino , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Tendões/efeitos dos fármacos , Alicerces Teciduais/química
14.
Biomaterials ; 34(2): 331-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23092861

RESUMO

One-step scaffold fabrication with live cell incorporation is a highly desirable technology for tissue engineering and regeneration. Projection stereolithography (PSL) represents a promising method owing to its fine resolution, high fabrication speed and computer-aided design (CAD) capabilities. However, the majority of current protocols utilize water-insoluble photoinitiators that are incompatible with live cell-fabrication, and ultraviolet (UV) light that is damaging to the cellular DNA. We report here the development of a visible light-based PSL system (VL-PSL), using lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) as the initiator and polyethylene glycol diacrylate (PEGDA) as the monomer, to produce hydrogel scaffolds with specific shapes and internal architectures. Furthermore, live human adipose-derived stem cells (hADSCs) were suspended in PEGDA/LAP solution during the PSL process, and were successfully incorporated within the fabricated hydrogel scaffolds. hADSCs in PEG scaffolds showed high viability (>90%) for up to 7 days after fabrication as revealed by Live/Dead staining. Scaffolds with porous internal architecture retained higher cell viability and activity than solid scaffolds, likely due to increased oxygen and nutrients exchange into the interior of the scaffolds. The VL-PSL should be applicable as an efficient and effective tissue engineering technology for point-of-care tissue repair in the clinic.


Assuntos
Hidrogel de Polietilenoglicol-Dimetacrilato/química , Ácidos Fosfínicos/química , Polietilenoglicóis/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Tecido Adiposo/citologia , Adulto , Células-Tronco Adultas/citologia , Sobrevivência Celular , Células Cultivadas , Desenho Assistido por Computador , Feminino , Humanos , Luz , Porosidade
15.
Stem Cell Res Ther ; 4 Suppl 1: S6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24564995

RESUMO

Osteoarthritis (OA), the most prevalent form of arthritis, affects up to 15% of the adult population and is principally characterized by degeneration of the articular cartilage component of the joint, often with accompanying subchondral bone lesions. Understanding the mechanisms underlying the pathogenesis of OA is important for the rational development of disease-modifying OA drugs. While most studies on OA have focused on the investigation of either the cartilage or the bone component of the articular joint, the osteochondral complex represents a more physiologically relevant target because the disease ultimately is a disorder of osteochondral integrity and function. In our current investigation, we are constructing an in vitro three-dimensional microsystem that models the structure and biology of the osteochondral complex of the articular joint. Osteogenic and chondrogenic tissue components are produced using adult human mesenchymal stem cells derived from bone marrow and adipose seeded within biomaterial scaffolds photostereolithographically fabricated with defined internal architecture. A three-dimensional-printed, perfusion-ready container platform with dimensions to fit into a 96-well culture plate format is designed to house and maintain the osteochondral microsystem that has the following features: an anatomic cartilage/bone biphasic structure with a functional interface; all tissue components derived from a single adult mesenchymal stem cell source to eliminate possible age/tissue-type incompatibility; individual compartments to constitute separate microenvironment for the synovial and osseous components; accessible individual compartments that may be controlled and regulated via the introduction of bioactive agents or candidate effector cells, and tissue/medium sampling and compositional assays; and compatibility with the application of mechanical load and perturbation. The consequences of mechanical injury, exposure to inflammatory cytokines, and compromised bone quality on degenerative changes in the cartilage component are examined in the osteochondral microsystem as a first step towards its eventual application as an improved and high-throughput in vitro model for prediction of efficacy, safety, bioavailability, and toxicology outcomes for candidate disease-modifying OA drugs.


Assuntos
Osteoartrite/patologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Técnicas de Cultura de Células , Microambiente Celular , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Modelos Biológicos , Osteoartrite/metabolismo , Engenharia Tecidual
16.
J Biomed Mater Res A ; 88(3): 725-34, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18335535

RESUMO

Bone tissue-derived biomaterials have often been applied for bone repair because of their similarity to human bone in structure and composition. When combined with growth factors, they could accelerate bone formation. Here, we explore a collagen containing mineralized bone-derived matrix (CCMBM) from bovine bone tissues, which not only maintains proper mechanical strength but also binds to the collagen-binding recombinant human collagen-binding bone morphogenetic protein-2 (CBD-BMP(2)). By analyzing its morphology and composition, we found that CCMBM was porous and mainly composed of calcium compounds. CCMBM could provide mechanical support for bone injury repair. It also showed good biocompatibility and proper degradation rate that would be helpful for bone regeneration. In addition, the intentionally preserved collagen allowed the specific binding of CBD-BMP(2) to CCMBM, and resulted in significantly increased osteogenesis in vivo. The results indicated that the combination of CCMBM with collagen-binding BMP(2) could be emerged into an effective medical device for bone repair.


Assuntos
Matriz Óssea/metabolismo , Proteína Morfogenética Óssea 2/metabolismo , Calcificação Fisiológica , Colágeno/metabolismo , Animais , Materiais Biocompatíveis/metabolismo , Matriz Óssea/ultraestrutura , Bovinos , Células Cultivadas , Colágeno/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Osteogênese , Ratos , Ratos Wistar
17.
Tissue Eng Part A ; 15(1): 13-21, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18652539

RESUMO

Stem cell-based therapy has been a promising method for tissue regeneration and wound repair. Adult adipose-derived stromal cells (ADSCs) are often used for adipose and bone tissue reconstruction because of their abundant sources and multipotential differentiation ability. When combined with carriers, ADSCs could be useful for constructing tissue substitutes in vitro or facilitating tissue regeneration in vivo. Demineralized bone matrix (DBM) has been used for tissue reconstruction because collagen presents good cell compatibility. However, DBM degrades rapidly when used for three-dimensional ADSC culture. Here DBM was crosslinked with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide and N-hydroxysulfosuccinimide to investigate whether crosslinked DBM (CRL-DBM) could be used as ADSC carrier. CRL-DBM showed not only improved mechanical property and enhanced stability, but also sustained ADSC proliferation and effective differentiation into adipocytes and bone lineage cells. The results indicated that CRL-DBM may be a suitable ADSC carrier for adipose and bone tissue regeneration.


Assuntos
Tecido Adiposo/citologia , Matriz Óssea/química , Diferenciação Celular , Proliferação de Células , Células Estromais/fisiologia , Fosfatase Alcalina/metabolismo , Animais , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Técnica de Desmineralização Óssea , Bovinos , Células Cultivadas , Reagentes de Ligações Cruzadas/química , Histocitoquímica , Imageamento Tridimensional , Masculino , Ratos , Ratos Sprague-Dawley , Células Estromais/citologia , Células Estromais/ultraestrutura , Alicerces Teciduais
18.
Growth Factors ; 25(5): 309-18, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18236209

RESUMO

Studies have shown that exogenous platelet-derived growth factor-BB (PDGF-BB) could accelerate the ulcer healing, but the lack of efficient growth factor delivery system limits its clinical application. Our previous work has demonstrated that the native human PDGF-BB was added a collagen-binding domain (CBD), TKKTLRT, to develop a collagen-based PDGF targeting delivery system. Here, we showed that this CBD-fused PDGF-BB (CBD-PDGF) could bind to collagen membrane efficiently. We used the rabbit dermal ischemic ulcer model to study the effects of CBD-PDGF loaded on collagen membranes. Results revealed that this system maintained a higher concentration and stronger bioactivity of PDGF-BB on the collagen membranes and promoted the re-epithelialization of dermal ulcer wounds, the collagen deposition, and the formation of capillary lumens within the newly formed tissue area. It demonstrated that collagen membranes loaded with collagen-targeting human PDGF-BB could effectively promote ulcer healing.


Assuntos
Indutores da Angiogênese/administração & dosagem , Colágeno/administração & dosagem , Fator de Crescimento Derivado de Plaquetas/administração & dosagem , Úlcera Cutânea/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Indutores da Angiogênese/metabolismo , Animais , Becaplermina , Colágeno/metabolismo , Sistemas de Liberação de Medicamentos , Epitélio/crescimento & desenvolvimento , Humanos , Membranas Artificiais , Neovascularização Fisiológica/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-sis , Coelhos , Pele/irrigação sanguínea
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