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1.
Medicine (Baltimore) ; 99(10): e19458, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32150103

RESUMO

BACKGROUND: Everolimus-eluting bioresorbable vascular scaffolds (BVS), which have the characteristics of scaffold absorption and vascular function recovery, are the latest innovation in the treatment of coronary artery disease. This new concept has become a hot topic in the field of interventional cardiology. Data regarding mid-term clinical outcomes of BVS in acute coronary syndromes are currently scarce. The aim of this systematic review and meta-analysis is to compare mid-term outcome data for BVS and second-generation drug-eluting stents (DES) in the treatment of acute coronary syndromes. METHODS: We searched PubMed, Embase, the Cochrane Library, Web of Science, and relevant web sites for studies with a follow-up of ≥ 1 years that studied percutaneous coronary interventions with BVS vs second-generation DES in acute coronary syndromes. A meta-analysis was performed with the software RevMan following the standards of the Cochrane Handbook for Systematic Reviews of Interventions 5.1.0. RESULTS: Five studies, 2 randomized controlled trials, and 3 observational studies, with a total of 1758 patients (BVS n = 917; DES n = 841) and a median follow-up duration of 24 months, were included. BVS, when compared with DES, resulted in higher rates of target lesion revascularization (TLR) (OR, 2.20; 95% CI, 1.12-3.64; P = .02) and stent/scaffold thrombosis (ST/ScT) (OR = 2.35, 95% CI: 1.13-4.89, P = .02). When TLR due to device thrombosis were excluded, the difference in risk estimates between the 2 groups was no longer significant (OR: 1.67, 95% CI: 0.73-3.82, P = .22). The risk for all-cause death (OR = 1.32 95% CI: 0.61-2.88, P = .48), cardiac death (OR = 1.29, 95% CI: 0.58-2.86 P = .52), target vessel myocardial infarction (OR = 1.50, 95% CI: 0.86-2.61, P = .15), and target lesion failure (OR = 1.34, 95% CI: 0.76-2.35, P = .31) did not differ between BVS and DES groups. CONCLUSION: At mid-term follow-up, BVS had a higher risk of TLR and ST/ScT than the second-generation DES in patients with acute coronary syndromes. ST/ScT was the key factor indicating the decreased safety and effectiveness of BVS relative to DES.


Assuntos
Implantes Absorvíveis , Síndrome Coronariana Aguda/cirurgia , Stents Farmacológicos , Tecidos Suporte , Everolimo , Humanos , Intervenção Coronária Percutânea , Desenho de Prótese , Fatores de Risco , Resultado do Tratamento
2.
Int J Oral Sci ; 12(1): 6, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32024822

RESUMO

Natural bone is a mineralized biological material, which serves a supportive and protective framework for the body, stores minerals for metabolism, and produces blood cells nourishing the body. Normally, bone has an innate capacity to heal from damage. However, massive bone defects due to traumatic injury, tumor resection, or congenital diseases pose a great challenge to reconstructive surgery. Scaffold-based tissue engineering (TE) is a promising strategy for bone regenerative medicine, because biomaterial scaffolds show advanced mechanical properties and a good degradation profile, as well as the feasibility of controlled release of growth and differentiation factors or immobilizing them on the material surface. Additionally, the defined structure of biomaterial scaffolds, as a kind of mechanical cue, can influence cell behaviors, modulate local microenvironment and control key features at the molecular and cellular levels. Recently, nano/micro-assisted regenerative medicine becomes a promising application of TE for the reconstruction of bone defects. For this reason, it is necessary for us to have in-depth knowledge of the development of novel nano/micro-based biomaterial scaffolds. Thus, we herein review the hierarchical structure of bone, and the potential application of nano/micro technologies to guide the design of novel biomaterial structures for bone repair and regeneration.


Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Engenharia Tecidual , Tecidos Suporte , Osso e Ossos , Humanos
3.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(2): 226-233, 2020 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-32030956

RESUMO

Objective: To explore the possibility of constructing tissue engineered adipose by adipose tissue derived extracellular vesicles (hAT-EV) combined with decellularized adipose tissue (DAT) scaffolds, and to provide a new therapy for soft tissue defects. Methods: The adipose tissue voluntarily donated by the liposuction patient was divided into two parts, one of them was decellularized and observed by HE and Masson staining and scanning electron microscope (SEM). Immunohistochemical staining and Western blot detection for collagen type Ⅰ and Ⅳ and laminin were also employed. Another one was incubated with exosome-removed complete medium for 48 hours, then centrifuged to collect the medium and to obtain hAT-EV via ultracentrifugation. The morphology of hAT-EV was observed by transmission electron microscopy; the nanoparticle tracking analyzer (NanoSight) was used to analyze the size distribution; Western blot was used to analyse membrane surface protein of hAT-EV. Adipose derived stem cells (ADSCs) were co-cultured with PKH26 fluorescently labeled hAT-EV, confocal fluorescence microscopy was used to observe the uptake of hAT-EV by ADSCs. Oil red O staining was used to evaluate adipogenic differentiation after hAT-EV and ADSCs co-cultured for 15 days. The DAT was scissored and then injected into the bilateral backs of 8 C57 mice (6-week-old). In experimental group, 0.2 mL hAT-EV was injected weekly, and 0.2 mL PBS was injected weekly in control group. After 12 weeks, the mice were sacrificed, and the new fat organisms on both sides were weighed. The amount of new fat was evaluated by HE and peri-lipoprotein immunofluorescence staining to evaluate the ability of hAT-EV to induce adipogenesis in vivo. Results: After acellularization of adipose tissue, HE and Masson staining showed that DAT was mainly composed of loosely arranged collagen with no nucleus; SEM showed that no cells and cell fragments were found in DAT, and thick fibrous collagen bundles could be seen; immunohistochemical staining and Western blot detection showed that collagen type Ⅰ and Ⅳ and laminin were retained in DAT. It was found that hAT-EV exhibited a spherical shape of double-layer envelope, with high expressions of CD63, apoptosis-inducible factor 6 interacting protein antibody, tumor susceptibility gene 101, and the particle size of 97.9% hAT-EV ranged from 32.67 nmto 220.20 nm with a peak at 91.28 nm. Confocal fluorescence microscopy and oil red O staining showed that hAT-EV was absorbed by ADSCs and induced adipogenic differentiation. In vivo experiments showed that the wet weight of fat new organisms in the experimental group was significantly higher than that in the control group ( t=2.278, P=0.048). HE staining showed that the structure of lipid droplets in the experimental group was more than that in the control group, and the collagen content in the control group was higher than that in the experimental group. The proportion of new fat in the experimental group was significantly higher than that in the control group ( t=4.648, P=0.017). Conclusion: DAT carrying hAT-EV can be used as a new method to induce adipose tissue regeneration and has a potential application prospect in the repair of soft tissue defects.


Assuntos
Tecido Adiposo , Adipócitos , Animais , Diferenciação Celular , Células Cultivadas , Espaço Extracelular , Humanos , Camundongos , Células-Tronco , Engenharia Tecidual , Tecidos Suporte
4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(1): 112-118, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32096384

RESUMO

Tricalcium phosphate (TCP) is one of the most widely used bioceramics for constructing bone tissue engineering scaffold. The three-dimensional (3D) printed TCP scaffold has precise and controllable pore structure, while with the limitation of insufficient mechanical properties. In this study, we investigated the effect of sintering temperature on the mechanical properties of 3D-printed TCP scaffolds in detail, due to the important role of the sintering process on the mechanical properties of bioceramic scaffolds. The morphology, mass and volume shrinkage, porosity, mechanical properties and degradation property of the scaffold was studied. The results showed that the scaffold sintered at 1 150℃ had the maximum volume shrinkage, the minimum porosity and optimal mechanical strength, with the compressive strength of (6.52 ± 0.84) MPa and the compressive modulus of (100.08 ± 18.6) MPa, which could meet the requirements of human cancellous bone. In addition, the 1 150℃ sintered scaffold degraded most slowly in the acidic environment compared to the scaffolds sintered at the other temperatures, demonstrating its optimal mechanical stability over long-term implantation. The scaffold can support bone mesenchymal stem cells (BMSCs) adherence and rapid proliferation and has good biocompatibility. In summary, this paper optimizes the sintering process of 3D printed TCP scaffold and improves its mechanical properties, which lays a foundation for its application as a load-bearing bone.


Assuntos
Fosfatos de Cálcio/química , Impressão Tridimensional , Engenharia Tecidual , Tecidos Suporte , Humanos , Teste de Materiais , Porosidade
5.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(1): 179-184, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32096393

RESUMO

Decellularized extracellular matrix (dECM) has been widely used as a scaffold for regenerative medicine due to its high biomimetic and excellent biocompatibility. As a functional polymer material with high water content and controlled fluidity, hydrogel is very promising for some minimally invasive surgery in clinical practice. In recent years, with the rapid development of hydrogel theory and technology, dECM hydrogel has gradually become a research hotspot in the field of regenerative medicine. In this paper, the related researches in recent years are reviewed regarding the preparation of dECM hydrogel and its preclinical application. The future clinical use is also prospected.


Assuntos
Matriz Extracelular , Hidrogéis , Medicina Regenerativa , Engenharia Tecidual , Humanos , Tecidos Suporte
6.
J Photochem Photobiol B ; 203: 111741, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31901721

RESUMO

Spinal cord injury (SCI) is a distressing injury and an irretrievable dramatic event that can debilitate victims for lifespan. Recovery and treatment of SCI is critical challenges for medicine, to overcome the hurdles stem cells and hydrogel scaffolds implantation is a boon for SCI recovery. In this regard, we reported the synthesis of Gold nanoparticles (Au NPs) loaded Agarose/Poly (N-isopropylacrylamide) (PNIPAM) as promising materials for SCI treatment. Herein, Au NPs was synthesized by well-established citrate reduction method and the prepared materials were characterised by UV-visible spectroscopy (UV-vis), Transmission electron microscopy (TEM), Fourier- transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), and EDAX analysis. The microscopic images showed an elliptical or ovoid porous structure nature of hydrogel, and successful and homogenous loading of photo plasmonic nanoparticles into the hydrogel structure. The in vitro cell viability and inflammation analyses data exhibited that prepared hydrogels have no toxic to the cells and displayed high anti-regenerative ability with bone marrow Mesenchymal stem cells (MSCs) and macrophages cells. The in vivo analysis study demonstrated that the treated materials with encapsulated MSCs have greater nerve tissue regeneration efficacy which was confirmed by the results of BBB scores. The hind limb locomotion of treated model animals was totally vanished after post-operational surgery. It's established that implanted nano-hydrogel materials combined with MSCs have quicker recovery of motor function after post-operative surgery, when compared to the other implanted animal groups.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Transplante de Células-Tronco Mesenquimais , Nanopartículas Metálicas/química , Traumatismos da Medula Espinal/terapia , Bexiga Urinária/fisiopatologia , Resinas Acrílicas/química , Animais , Células da Medula Óssea/citologia , Ouro/química , Membro Posterior/fisiologia , Locomoção , Células-Tronco Mesenquimais/química , Células-Tronco Mesenquimais/citologia , Tecido Nervoso/fisiologia , Regeneração , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/patologia , Tecidos Suporte/química
7.
Plast Reconstr Surg ; 145(2): 337e-347e, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31985634

RESUMO

BACKGROUND: Three-dimensionally-printed bioceramic scaffolds composed of ß-tricalcium phosphate delivering the osteogenic agent dipyridamole can heal critically sized calvarial defects in skeletally mature translational models. However, this construct has yet to be applied to growing craniofacial models. In this study, the authors implanted three-dimensionally-printed bioceramic/dipyridamole scaffolds in a growing calvaria animal model and evaluated bone growth as a function of geometric scaffold design and dipyridamole concentration. Potential adverse effects on the growing suture were also evaluated. METHODS: Bilateral calvarial defects (10 mm) were created in 5-week-old (approximately 1.1 kg) New Zealand White rabbits (n = 16 analyzed). Three-dimensionally-printed bioceramic scaffolds were constructed in quadrant form composed of varying pore dimensions (220, 330, and 500 µm). Each scaffold was coated with collagen and soaked in varying concentrations of dipyridamole (100, 1000, and 10,000 µM). Controls consisted of empty defects. Animals were killed 8 weeks postoperatively. Calvariae were analyzed using micro-computed tomography, three-dimensional reconstruction, and nondecalcified histologic sectioning. RESULTS: Scaffold-induced bone growth was statistically greater than bone growth in empty defects (p = 0.02). Large scaffold pores, 500 µm, coated in 1000 µM dipyridamole yielded the most bone growth and lowest degree of scaffold presence within the defect. Histology showed vascularized woven and lamellar bone along with initial formation of vascular canals within the scaffold lattice. Micro-computed tomographic and histologic analysis revealed patent calvarial sutures without evidence of ectopic bone formation across all dipyridamole concentrations. CONCLUSION: The authors present an effective pediatric bone tissue-engineering scaffold design and dipyridamole concentration that is effective in augmentation of calvarial bone generation while preserving cranial suture patency.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/uso terapêutico , Dipiridamol/uso terapêutico , Fraturas Cranianas/cirurgia , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Dipiridamol/administração & dosagem , Modelos Animais de Doenças , Coelhos , Crânio/efeitos dos fármacos , Crânio/lesões , Fraturas Cranianas/tratamento farmacológico
8.
DNA Cell Biol ; 39(3): 451-458, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31910350

RESUMO

Gene delivery from tissue engineering scaffold is a novel strategy in regulating long-term growth and function of cells in vitro culture. In this study, a hepatocyte growth factor plasmid/polyetherimide (pHGF/PEI) polyplex delivering alginate (AL)/galactosylated chitosan (GC) (pHGF/PEI-AL/GC) sponge scaffold was prepared for the in vitro coculture of hepatocytes/3T3 cells. The pHGF/PEI polyplex released for 6 days in the sponge scaffold with weight ratio of AL/GC being 3:1 and fixed amount of pHGF being 40 µg (24-well scaffold). In addition, the 3T3 cells culturing in the pHGF/PEI-AL/GC sponge scaffold could be continually transfected and expressed the exogenous HGF for 6 days. Furthermore, the albumin secretion and urea synthesis of hepatocytes were significantly enhanced when cocultured with 3T3 cells in the pHGF/PEI-AL/GC sponge scaffold compared with that in the AL/GC sponge without pHGF. In summary, the preparation of AL/GC sponge scaffold delivering pHGF/PEI polyplex is a critical significance for maintaining the long-term survival and function of primary hepatocytes in vitro.


Assuntos
Quitosana/análogos & derivados , Técnicas de Transferência de Genes , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos/metabolismo , Tecidos Suporte/química , Células 3T3 , Alginatos/química , Animais , Células Cultivadas , Técnicas de Cocultura/métodos , Galactose/análogos & derivados , Fator de Crescimento de Hepatócito/genética , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Masculino , Camundongos , Polímeros/química , Ratos , Ratos Wistar , Tecidos Suporte/efeitos adversos
9.
Life Sci ; 240: 117066, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31738881

RESUMO

Tissue engineering and the use of scaffolds have shown high therapeutic potentialities about male and female infertility. Nowadays, many couples are suffering from infertility problems. There are different causes for infertility including chemotherapy (for male and female), uterine injuries, and intrauterine adhesions. Extra-cellular matrix in tissue engineering provides a supportive medium for blood or lymphatic vessels making it a suitable substrate for cell implantation and growth. Dominant successes in this branch have been in use of patient-derived primary cells, these cells loaded in scaffolds and used to generate tissue for re-implantation. However, this method has limitations, because of the invasive nature of cell collection, also the cells patient-derived may be not healthy and become the source of disease. Therefore, use of stem cells, including embryonic stem (ES) cells, bone marrow mesenchymal stem cells (BM-MSCs) and umbilical cord-derived mesenchymal stem cells (UC-MSCs) have been considered. Cell/scaffold systems have a substantial role in fertility organs or agents repair or regeneration. This review summarizes the novel scaffold-based tissue engineering approaches to treat infertility.


Assuntos
Infertilidade Feminina/terapia , Infertilidade Masculina/terapia , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Feminino , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais , Gravidez , Transplante de Células-Tronco
10.
J Surg Res ; 246: 62-72, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31561179

RESUMO

Recurrence rates in the laparoscopic repair of the hiatal hernia range from 12% to 59%. Limitation of reinforcement has been principally the risk of adverse events caused by synthetic materials. Biologic and resorbable synthetic materials are valid alternatives. This study compares the host response to all these materials after hiatal hernia repair. A total of 20 Landrace pigs, underwent laparoscopic primary hiatal hernia repair and reinforced with a polypropylene mesh (PROLENE: polypropylene [PP]), an absorbable synthetic scaffold (GOREBIO-A: polyglycolic acid [PGA]), a urinary bladder matrix scaffold, (Gentrix: urinary bladder matrix [UBM]), or without reinforcement, control group (C). Animals were survived for 3 months. Endpoints included gross morphology, biomechanical testing, and histology. Pigs in PP and PGA groups showed fibrosis at the repair site, with robust adhesions. In UBM and C groups, only mild adhesions were found. Load at failure (gr) and stiffness (gr/mm) of PP were higher than C group (PP:2103 ± 548.3 versus C:951.1 ± 372.7, P = 0.02; PP:643.3 ± 301 versus C:152.6 ± 142.7, P = 0.01). PGA and UBM values for both parameters were in between PP and C samples. However, stiffness in UBM was tended to be lower than PP group, and approached a significant difference (643.3 ± 301 versus 243 ± 122.1, P = 0.0536). In UBM group, the histology resembled native tissue. By contrast, PP and PGA groups showed mononuclear infiltrates, fibroencapsulation, necrosis, remnants of mesh, and disorganized tissue that was validated with a histologic score. In this setting, UBM scaffolds showed the most appropriate features for hiatal hernia repair, recovering the tissue properties that can help reduce the possibility of early failure and prevent complications associated with the implanted material.


Assuntos
Materiais Biocompatíveis , Hérnia Hiatal/cirurgia , Herniorrafia/instrumentação , Prevenção Secundária/instrumentação , Tecidos Suporte , Implantes Absorvíveis , Animais , Modelos Animais de Doenças , Feminino , Herniorrafia/métodos , Humanos , Teste de Materiais , Prevenção Secundária/métodos , Estresse Mecânico , Telas Cirúrgicas , Sus scrofa
11.
J Photochem Photobiol B ; 202: 111677, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31810037

RESUMO

In this examination, chitosan-silk fibroin/polyethylene terephthalate (CTS-SF/PET), chitosan-silk fibroin/polyethylene terephthalate/hydroxyapatite (CTS-SF/PET/HAP) and chitosan-silk fibroin/polyethylene terephthalate/Silver @hydroxyapatite (CTS-SF/PET/Ag@HAP) scaffolds were prepared by utilizing the plasma splashing procedure. Field emission scanning electron microscopy (FESEM) results demonstrated that the outside of the PET covered with HAP nanoparticles. The cell viability results demonstrated that the number of Mesenchymal stem cells (MSCs) primarily spread out on CTS-SF/PET/Ag@HAP. RT-PCR results demonstrated that there was an upregulated mRNA articulation of osseous development-related properties in the CTS-SF/PET/Ag@HAP composite. The in vivo rabbit animal assessment scores of the CTS-SF/PET/Ag@HAP composite were significantly better than those of the CTS-SF/PET at 1 to 3 months. Both in-vivo and in-vitro results exhibited in this investigation recommend that the cytocompatibility and osseointegration of CTS-SF/PET/Ag@HAP tendon were fundamentally improved by expanding the multiplication of cells and up-regulating the outflow of tendon development-related properties. In conclusion, the CTS-SF/PET/Ag@HAP tendon is a promising candidate for Anterior Cruciate Ligament (ACL) replacement in the future.


Assuntos
Ligamento Cruzado Anterior/fisiologia , Materiais Biocompatíveis/química , Durapatita/química , Nanopartículas/química , Osseointegração , Prata/química , Animais , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Artropatias/reabilitação , Artropatias/terapia , Artropatias/veterinária , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/toxicidade , Osseointegração/efeitos dos fármacos , Coelhos , Tecidos Suporte/química
12.
J Photochem Photobiol B ; 202: 111680, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31810038

RESUMO

Tissue engineering and stem cell rehabilitation are the hopeful aspects that are being investigated for the management of Myocardial Infarction (MI); cardiac patches have been used to start myocardial rejuvenation. In this study, we engineered p-phenylenediamine surface functionalized (modif-CQD) into the Silk fibroin/PLA (SF/PLA) nanofibrous bioactive scaffolds with improved physico-chemical abilities, mechanical and cytocompatibility to cardiomyocytes. The micrograph results visualized the morphological improved spherical modif-CQD have been equivalently spread throughout the SF/PLA bioactive cardiac scaffolds. The fabricated CQD@SF/PLA nanofibrous bioactive scaffolds were highly porous with fully consistent pores; effectively improved young modulus and swelling asset for the suitability and effective implantation efficacy. The scaffolds were prepared with rat cardiomyocytes and cultured for up to 7 days, without electrical incentive. After 7 days of culture, the scaffold pores all over the construct volume were overflowing with cardiomyocytes. The metabolic activity and viability of the cardiomyocytes in CQD@SF/PLA scaffolds were significantly higher than cardiomyocytes in Silk fibroin /PLA scaffolds. The integration of CQD also influenced greatly and increases the expression of cardiac-marker genes. The results of the present investigations evidently recommended that well-organized cardiac nanofibrous scaffold with greater cardiac related mechanical abilities and biocompatibilities for cardiac tissue engineering and nursing care applications.


Assuntos
Fibroínas/química , Nanofibras/química , Pontos Quânticos/química , Engenharia Tecidual , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Carbono/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Raios Infravermelhos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Nanofibras/toxicidade , Poliésteres/química , RNA Mensageiro/metabolismo , Ratos , Troponina C/genética , Troponina C/metabolismo
13.
J Surg Oncol ; 121(1): 121-128, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31209884

RESUMO

Secondary lymphedema is a worldwide affliction that exacts a significant public health burden. This review examines the etiology, presentation, and management of secondary lymphedema. In addition, emerging adjunctive strategies are explored, specifically evidence from animal and pilot human studies regarding implantation of a collagen nanofibrillar scaffold (BioBridge™; Fibralign Corporation, Union City, CA) in promoting lymphangiogenesis, preventing and treating lymphedema, and enhancing outcomes with lymphaticovenous anastomosis and vascularized lymph node transfer.


Assuntos
Colágeno , Linfedema/cirurgia , Tecidos Suporte , Animais , Humanos , Linfonodos/cirurgia , Linfangiogênese , Modelos Animais , Nanofibras , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Engenharia Tecidual
14.
Clin Oral Investig ; 24(2): 663-674, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31119382

RESUMO

OBJECTIVES: This study aimed to develop a porous chitosan-calcium-aluminate scaffold (CH-AlCa) in combination with a bioactive dosage of 1α,25-dihydroxyvitamin D3 (1α,25VD), to be used as a bioactive substrate capable to increase the odontogenic potential of human dental pulp cells (HDPCs). MATERIALS AND METHODS: The porous CH-AlCa was developed by the incorporation of an AlCa suspension into a CH solution under vigorous agitation, followed by phase separation at low temperature. Scaffold architecture, porosity, and calcium release were evaluated. Thereafter, the synergistic potential of CH-AlCa and 1 nM 1α,25VD, selected by a dose-response assay, for HDPCs seeded onto the materials was assessed. RESULTS: The CH-AlCa featured an organized and interconnected pore network, with increased porosity in comparison with that of plain chitosan scaffolds (CH). Increased odontoblastic phenotype expression on the human dental pulp cell (HDPC)/CH and HDPC/CH-AlCa constructs in the presence of 1 nM 1α,25VD was detected, since alkaline phosphatase activity, mineralized matrix deposition, dentin sialophosphoprotein/dentin matrix acidic phosphoprotein 1 mRNA expression, and cell migration were overstimulated. This drug featured a synergistic effect with CH-AlCa, since the highest values of cell migration and odontoblastic markers expression were observed in this experimental condition. CONCLUSIONS: The experimental CH-AlCa scaffold increases the chemotaxis and regenerative potential of HDPCs, and the addition of low-dosage 1α,25VD to this scaffold enhances the potential of these cells to express an odontoblastic phenotype. CLINICAL RELEVANCE: Chitosan scaffolds enriched with calcium-aluminate in association with low dosages of 1α,25-dihydroxyvitamin D3 provide a highly bioactive microenvironment for dental pulp cells prone to dentin regeneration, thus providing potential as a cell-free tissue engineering system for direct pulp capping.


Assuntos
Polpa Dentária , Cálcio , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Quitosana , Humanos , Odontoblastos , Tecidos Suporte
15.
Adv Biochem Eng Biotechnol ; 171: 279-319, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31468094

RESUMO

Bioprinting technology is a strong tool in producing living functional tissues and organs from cells, biomaterial-based bioinks, and growth factors in computer-controlled platform. The aim of this chapter is to present recent progresses in bioprinting of nerve, skin, cardiac, bone, cartilage, skeletal muscle, and other soft tissues and highlight the challenges in these applications. Various composite bioinks with bioactive ceramic-based scaffolds having patient-specific design and controlled micro-architectures were used at clinical and preclinical applications successfully for regeneration of bone. In nerve tissue engineering, bioprinting of alginate- and gelatin-based gel bioinks by extrusion presented a controllable 3D microstructures and showed satisfactory cytocompatibility and axonal regeneration. Bioprinting of cardiac progenitors in biopolymers resulted in limited success, while the use of bioinks from extracellular matrix induced satisfactory results in cardiac regeneration. Osteochondral scaffold bioprinting is challenging due to the complex hierarchical structure and limited chondral regeneration. Therefore, current approaches focused on osteochondral scaffold with vascular network and mimicking hierarchical structures. The applications of bioprinting in other types of tissues were also studied, and results showed significant potentials in regeneration of tissues such as cornea, liver, and urinary bladder.


Assuntos
Bioimpressão , Osso e Ossos , Matriz Extracelular , Humanos , Impressão Tridimensional , Engenharia Tecidual , Tecidos Suporte
16.
Cell Prolif ; 53(1): e12730, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746040

RESUMO

OBJECTIVES: In peripheral neuropathy, the underlying mechanisms of nerve and muscle degeneration include chronic inflammation and oxidative stress in fibrotic tissues. (-)-Epigallocatechin gallate (EGCG) is a major, active component in green tea and may scavenge free radical oxygen and attenuate inflammation. Conservative treatments such as steroid injection only deal with early, asymptomatic, peripheral neuropathy. In contrast, neurolysis and nerve conduit implantation work effectively for treating advanced stages. MATERIALS AND METHODS: An EGCG-loaded polycaprolactone (PCL) porous scaffold was fabricated using an integrated moulding method. We evaluated proliferative, oxidative and inflammatory activity of rat Schwann cells (RSCs) and rat skeletal muscle cells (RSMCs) cultured on different scaffolds in vitro. In a rat radiation injury model, we assessed the morphological, electrophysiological and functional performance of regenerated sciatic nerves and gastrocnemius muscles, as well as oxidative stress and inflammation state. RESULTS: RSCs and RSMCs exhibited higher proliferative, anti-oxidant and anti-inflammatory states in an EGCG/PCL scaffold. In vivo studies showed improved nerve and muscle recovery in the EGCG/PCL group, with increased nerve myelination and muscle fibre proliferation and reduced macrophage infiltration, lipid peroxidation, inflammation and oxidative stress indicators. CONCLUSIONS: The EGCG-modified PCL porous nerve scaffold alleviates cellular oxidative stress and repairs peripheral nerve and muscle structure in rats. It attenuates oxidative stress and inflammation in vivo and may provide further insights into peripheral nerve repair in the future.


Assuntos
Catequina/análogos & derivados , Regeneração Nervosa/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Estresse Oxidativo , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Poliésteres , Lesões Experimentais por Radiação/tratamento farmacológico , Células de Schwann/metabolismo , Nervo Isquiático/fisiologia , Tecidos Suporte/química , Animais , Catequina/química , Catequina/farmacologia , Linhagem Celular , Músculo Esquelético/inervação , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Poliésteres/química , Poliésteres/farmacologia , Porosidade , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Ratos , Células de Schwann/patologia , Nervo Isquiático/lesões , Nervo Isquiático/patologia
17.
Cell Prolif ; 53(1): e12725, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746058

RESUMO

OBJECTIVES: Activation of the sympathetic system and adrenergic ß-receptors following traumatic bone defects negatively impairs bone regeneration. Whether preventing ß-receptor activation could potentially improve bone defect repair is unknown. In this study, we investigated the effect of systematic administration and local delivery of propranolol through composite scaffolds on bone healing. MATERIALS AND METHODS: Collagen/PVA/propranolol/hydroxyapatite(CPPH)composite scaffolds were fabricated with 3D printing technique and characterized by scanning electron microscope (SEM). Micro-CT analysis and bone formation histology were performed to detect new bone formation. Osteogenic differentiation of bone marrow stromal cells (BMSCs) and osteoclastogenesis of bone marrow monocytes cultured with scaffolds extract were performed for further verification. RESULTS: Intraperitoneal injection of propranolol did not significantly improve bone repair, as indicated by micro-CT analysis and bone formation histology. However, CPPH scaffolds exhibited sustained release of propranolol in vitro and significantly enhanced bone regeneration compared with vehicle collagen/PVA/hydroxyapatite (CPH) scaffolds in vivo. Moreover, in vitro experiments indicated the scaffolds containing propranolol promoted the osteogenic differentiation and migration of rat BMSCs and inhibited osteoclastogenesis by preventing ß-receptor activation. CONCLUSIONS: This study demonstrates that local adrenergic ß-receptor blockade can effectively enhance the treatment of bone defects by stimulating osteogenic differentiation, inhibiting osteoclastogenesis and enhancing BMSCs migration.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Células da Medula Óssea/metabolismo , Regeneração Óssea/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Propranolol/farmacologia , Tecidos Suporte/química , Antagonistas Adrenérgicos beta/química , Animais , Células da Medula Óssea/patologia , Colágeno/química , Colágeno/farmacologia , Implantes de Medicamento/farmacologia , Durapatita/química , Durapatita/farmacologia , Masculino , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia , Propranolol/química , Ratos , Ratos Sprague-Dawley , Células Estromais/metabolismo , Células Estromais/patologia
18.
Dent Mater ; 36(1): 76-87, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31735424

RESUMO

OBJECTIVE: Recent studies suggest xenogeneic extracellular matrices as potential regenerative tools in dental pulp regeneration. This study aimed to fabricate and characterize a novel three-dimensional macroporous pulp-derived scaffold that enables the attachment, penetration, proliferation and differentiation of mesenchymal stem cells. METHOD: Bovine pulp was decellularized and characterized with histological and DNA content methods. This scaffold was prepared using finely milled lyophilized decellularized pulp extracellular matrix (ECM) digested with pepsin. Three different concentrations of ECM (1.50, 2.25 and 3.00mg/ml) were freeze-dried and were tested with/without chemical crosslinking. The specimens were subjected to physicochemical characterization, cell viability and quantitative real time polymerase chain reaction assessments with human bone marrow mesenchymal stem cells (hBMMSCs). All scaffolds were subcutaneously implanted in rats for two weeks and histological and immunostaining analyses were performed. RESULTS: Histological and DNA analysis confirmed complete decellularization. All samples demonstrated more than 97% porosity and 1.50mg/ml scaffold demonstrated highest water absorption. The highest cell viability and proliferation of hBMMSCs was observed on the 3.00mg/ml crosslinked scaffolds. The gene expression analysis showed a significant increase of dmp-1 and collagen-I on 3.00mg/ml crosslinked scaffolds compared to the other scaffolds. Histological examination of subcutaneous implanted scaffolds revealed low immunological response, and enhanced angiogenesis in cross-linked samples compared to non-crosslinked samples. SIGNIFICANCE: The three-dimensional macroporous pulp-derived injectable scaffold developed and characterized in this study displayed potential for regenerative therapy. While the scaffold biodegradability was decreased by crosslinking, the biocompatibility of post-crosslinked scaffold was significantly improved.


Assuntos
Polpa Dentária , Tecidos Suporte , Animais , Bovinos , Diferenciação Celular , Matriz Extracelular , Humanos , Ratos , Regeneração , Engenharia Tecidual
19.
Adv Exp Med Biol ; 1212: 57-70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30989589

RESUMO

Decellularized tissues are gaining popularity as scaffolds for tissue engineering; they allow cell attachment, proliferation, differentiation, and are non-immunogenic. Adipose tissue is an abundant resource that can be decellularized and converted in to a bio-scaffold. Several methods have been developed for adipose tissue decellularization, typically starting with freeze thaw cycles, followed by washes with hypotonic/hypertonic sodium chloride solution, isopropanol, detergent (SDS, SDC and Triton X-100) and trypsin digestion. After decellularization, decellularized adipose tissue (DAT) can be converted into a powder, solution, foam, or sheet to allow for convenient subcutaneous implantation or to repair external injuries. Additionally, DAT bio-ink can be used to 3D print structures that closely resemble physiological tissues and organs. Proteomic analysis of DAT reveals that it is composed of collagens (I, III, IV, VI and VII), glycosaminoglycans, laminin, elastin, and fibronectin. It has also been found to retain growth factors like VEGF and bFGF after decellularization. DAT inherently promotes adipogenesis when seeded with adipose stem cells in vitro, and when DAT is implanted subcutaneously it is capable of recruiting host stem cells and forming adipose tissue in rodents. Furthermore, DAT has promoted healing in rat models of full-thickness skin wounds and peripheral nerve injury. These findings suggest that DAT is a promising candidate for repair of soft tissue defects, and is suitable for breast reconstruction post-mastectomy, wound healing, and adipose tissue regeneration. Moreover, since DAT's form and stiffness can be altered by physicochemical manipulation, it may prove suitable for engineering of additional soft and hard tissues.


Assuntos
Tecido Adiposo/química , Proteômica , Engenharia Tecidual/métodos , Tecidos Suporte/química , Tecido Adiposo/citologia , Animais , Humanos , Mastectomia/métodos
20.
Adv Exp Med Biol ; 1212: 71-85, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30707350

RESUMO

Decellularized organs and tissues are effectively utilized in a diversity of regenerative medicine purposes, and the decellularization approaches employed differ as broadly as the tissues/organs of concern. Biological scaffold substances formed by extracellular matrix (ECM) are mostly produced with methods that include decellularization of tissues. Conservation of the multifaceted arrangement and three-dimensional (3D) construction of the ECM is very wanted but it is documented that almost every approach of decellularization cause disturbance of the organization and possible forfeiture of surface organization and conformation. The competence of cell elimination from a tissue is reliant on the basis of the tissue and the precise physical, chemical, and enzymatic approaches that are utilized. Here, the most frequently applied and newly developed decellularization techniques are designated, organ engineering with decellularized scaffolds for different organs, recent knowledge in the field are explained.


Assuntos
Medicina Regenerativa , Engenharia Tecidual/métodos , Tecidos Suporte , Matriz Extracelular , Humanos , Medicina Regenerativa/métodos
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