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1.
Life Sci ; 264: 118502, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33031825

RESUMO

Bone tissue engineering compasses the use of mesenchymal stem cells (MSCs) along with engineered biomaterial construct to augment bone regeneration. Till now, MSCs were isolated from various sources and used in cellular constructs. For the first time, in this study, MSCs were isolated from human Ovarian Follicular Fluid (OFF) and characterized by CD 44+ and CD 105+ markers via confocal microscopy and flow cytometry. Additionally, MSCs stemness, proliferation and colony-forming unit ability, multi-lineage differentiation potential were also studied. To test its suitability for bone tissue engineering applications, we grew the MSCs with the conditioned medium obtained from biocomposite scaffold by fusing a natural polymer, Chitosan (CS) and a synthetic polymer, Polycaprolactone (PCL) and the scaffold were coated with Zinc divalent ions to impart osteogenic properties. The physico-chemical characterization of scaffold, such as FTIR, XRD, and SEM studies was carried out. The biological characterization showed that the scaffolds were compatible with MSCs and promoted osteoblast differentiation which was confirmed at both cellular and molecular levels. The cellular construct increased calcium deposition, analyzed by alizarin red staining and ALP activity at cellular level. At the molecular level, the osteoblast markers expression such as Runx2 and type 1 collagen mRNAs, and osteonectin (ON) and osteocalcin (OC) secretory proteins were increased in the presence of scaffold. Overall, the current study recommends that MSCs can be easily obtained from human waste OFF, and grown in standard in vitro conditions. Successful growth of such MSCs with CS/PCL/Zn scaffold opens new avenues in utilizing the cell source for bone tissue engineering.


Assuntos
Materiais Biocompatíveis , Regeneração Óssea/fisiologia , Líquido Folicular/fisiologia , Folículo Ovariano/fisiologia , Engenharia Tecidual/métodos , Tecidos Suporte , Adulto , Materiais Biocompatíveis/administração & dosagem , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Células Cultivadas , Quitosana/administração & dosagem , Feminino , Líquido Folicular/citologia , Líquido Folicular/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais , Recuperação de Oócitos/métodos , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Folículo Ovariano/efeitos dos fármacos , Poliésteres/administração & dosagem , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos , Zinco/administração & dosagem
2.
J Prosthet Dent ; 125(1): 1-7, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32111394

RESUMO

In February 2019, the American Prosthodontics Society asked me to "ponder" the future of dental biomaterials. This talk was titled, "Gazing Into Bob's Crystal Ball". My basic approach was guided by the words of Confucius, "Study the past if you would define the future." As I have often studied and lectured on how many of our important materials got into dentistry, it was a natural assignment. In this article, I review how key materials came to be used in dental practice and organize these "sources" into an extended classification, assuming future materials will likely derive from one of these. Then, I identify important examples in each category and then expound on likely future developments, some already in progress. These include increasing the use of and benefiting from automated systems; better engineering with existing materials by means of failure analysis (from clinically retrieved specimens); iterative improvements in materials and practices, again based on observations from clinical behavior; the use of scaffolds for both hard- and soft-tissue repair; and the development of "smart" materials. I hope this contribution survives the test of time. Please note that, importantly, this list includes not just materials but often-overlooked steps in processing that will affect their properties and clinical durability.


Assuntos
Materiais Biocompatíveis , Prostodontia , Odontólogos , Previsões , Humanos
3.
Facial Plast Surg ; 36(5): 517-527, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33368076

RESUMO

In Asian countries, augmentation rhinoplasty is especially common, where alloplastic implants are used much more commonly than autologous tissues. In rhinoplasty, such artificial materials include silicone, expanded polytetrafluoroethylene (ePTFE), porous high-density polyethylene (pHDPE), and acellular human dermis. As the use of implants has become increasingly common in rhinoplasty, more adverse effects such as infection, extrusion, movement, irregularities, absorption, prolonged swelling, seroma, and contracture have been recognized and reported in the literature. Surgeons should be able to recognize these probable complications and manage them successfully. Early detection and prompt management of the complication are essential for minimizing the severity of the deformity. Proper management of complications is key for the success of dorsal augmentation using alloplastic implants.


Assuntos
Implantes Dentários , Rinoplastia , Materiais Biocompatíveis/efeitos adversos , Humanos , Politetrafluoretileno/efeitos adversos , Próteses e Implantes/efeitos adversos , Rinoplastia/efeitos adversos , Silicones/efeitos adversos
4.
Int J Nanomedicine ; 15: 10183-10197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363374

RESUMO

Purpose: Nanoparticle (NP)-based chemo-photothermal therapy (CPT) has been shown to be a promising non-invasive approach for antitumor treatment. However, NPs must overcome the limitations of opsonization, clearance of the reticuloendothelial system, and ineffective targeting of tumor tissue sites. To solve these problems, stem cell membrane (SCM)-camouflaged polydopamine nanoparticles (PDA@SCM NPs) carrying the hydrophobic anticancer drug 7-ethyl-10-hydroxycamptothecin (SN38) were constructed for CPT of malignant bone tumors. Methods: We developed umbilical-cord mesenchymal stem cell membrane-coated polydopamine nanoparticles encapsulating SN38 (PDA-SN38@SCM NPs) as an efficient tumor-targeting drug-delivery platform for CPT of malignant bone tumors. We characterized PDA@SCM NPs and evaluated the biocompatibility and anti-phagocytosis properties of PDA@SCM NPs. The antitumor activity of PDA-SN38@SCM NPs was evaluated in MG63 lines and an MG63 xenograft model in mice. Results: Synthesized PDA-SN38@SCM NPs retained an excellent photothermal effect after SN38 loading. The drug release of PDA-SN38@SCM NPs could be triggered by near-infrared irradiation and an acidic stimulus. PDA@SCM NPs exhibited lower nonspecific macrophage uptake, longer retention in blood, and more effective accumulation at tumor sites than that shown by PDA NPs. Confocal laser scanning microscopy (CLSM) and flow cytometry showed that MG63 cells took up more PDA-SN38@SCM NPs than PDA-SN38 NPs. In vitro and in vivo antitumor studies demonstrated the outstanding performance of PDA-SN38@SCM NPs in synergistic CPT for bone tumors. Conclusion: PDA-SN38@SCM NPs demonstrated an extraordinary synergistic CPT effect and could be a promising strategy for the treatment of malignant bone tumors.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/terapia , Membrana Celular/metabolismo , Indóis/química , Nanopartículas/química , Polímeros/química , Células-Tronco/metabolismo , Animais , Antineoplásicos/farmacologia , Materiais Biocompatíveis/química , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Feminino , Humanos , Evasão da Resposta Imune/efeitos dos fármacos , Irinotecano/farmacocinética , Irinotecano/farmacologia , Irinotecano/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/ultraestrutura , Células RAW 264.7 , Distribuição Tecidual/efeitos dos fármacos
5.
Khirurgiia (Mosk) ; (12): 46-51, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33301253

RESUMO

Blakemore probe-obturator was previously preferable for primary hemostasis in patients with bleeding from esophageal varices. Currently, Danis self-expanding nitinol stent became an effective alternative. According to some manufacturers, Danis stent has some advantages over balloon tamponade. We report implantation of nitinol stent for hemostasis in a patient with multiple recurrent bleeding and ineffective endoscopic manipulations. A method of stent fixation for prevention of distal migration as the most common complication is described.


Assuntos
Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal , Hipertensão Portal , Ligas , Materiais Biocompatíveis , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/cirurgia , Esofagoscopia , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Hemostasia Cirúrgica/instrumentação , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/diagnóstico , Falha de Prótese , Implantação de Prótese/métodos , Stents
6.
Nat Commun ; 11(1): 6203, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33277474

RESUMO

Biomaterials hold promise for therapeutic applications in the central nervous system (CNS). Little is known about molecular factors that determine CNS foreign body responses (FBRs) in vivo, or about how such responses influence biomaterial function. Here, we probed these factors in mice using a platform of injectable hydrogels readily modified to present interfaces with different physiochemical properties to host cells. We found that biomaterial FBRs mimic specialized multicellular CNS wound responses not present in peripheral tissues, which serve to isolate damaged neural tissue and restore barrier functions. We show that the nature and intensity of CNS FBRs are determined by definable properties that significantly influence hydrogel functions, including resorption and molecular delivery when injected into healthy brain or stroke injuries. Cationic interfaces elicit stromal cell infiltration, peripherally derived inflammation, neural damage and amyloid production. Nonionic and anionic formulations show minimal levels of these responses, which contributes to superior bioactive molecular delivery. Our results identify specific molecular mechanisms that drive FBRs in the CNS and have important implications for developing effective biomaterials for CNS applications.


Assuntos
Materiais Biocompatíveis/farmacologia , Sistema Nervoso Central/efeitos dos fármacos , Reação a Corpo Estranho/prevenção & controle , Hidrogéis/farmacologia , Animais , Materiais Biocompatíveis/química , Biomimética , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/fisiopatologia , Feminino , Humanos , Hidrogéis/química , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
7.
Int J Nanomedicine ; 15: 9337-9353, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262591

RESUMO

Purpose: Autologous bone grafts are the gold standard for treating bone defects. However, limited bone supply and morbidity at the donor site restrict its extensive use. Therefore, developing bone graft materials as an alternative to autologous grafts has gained considerable attention. Injectable hydrogels endowed with osteogenic potential have the ability to fill irregular bone defects using minimally invasive procedures and have thus been attracting researchers' attention. However, from a clinical perspective, most fabrication methods employed for the current injectable osteogenic hydrogels are difficult and inconvenient. In the current study, we fabricated an injectable osteogenic hydrogel using a simple and convenient strategy. Materials and Methods: Gelatin-methacryloyl (GelMA) pre-polymer was synthetized. Nano silicate (SN) and stromal cell-derived factor-1 alpha (SDF-1α) were introduced into the pre-polymer to achieve injectability, controlled release property, excellent osteogenic ability, and efficient stem cell homing. Results: The GelMA-SN-SDF-1α demonstrated excellent injectability via a 17-G needle at room temperature. The loaded SDF-1α exhibited a long-term controlled release pattern and efficiently stimulated MSC migration and homing. The GelMA-SN-SDF-1α hydrogel amplified cell spreading, migration, osteogenic-related biomarker expression, and matrix mineralization. The GelMA-SN-SDF-1α hydrogel filled critical-sized calvaria defects in rats and demonstrated excellent bone regeneration ability, as assessed using micro-CT scanning and histomorphometric staining. Conclusion: The GelMA-SN-SDF-1α hydrogel provides a simple and convenient strategy for the fabrication of injectable osteogenic graft materials.


Assuntos
Osso e Ossos/citologia , Quimiocina CXCL12/química , Gelatina/química , Hidrogéis/química , Nanoestruturas/química , Silicatos/química , Engenharia Tecidual , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Movimento Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ratos
8.
Int J Nanomedicine ; 15: 9389-9405, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262594

RESUMO

Introduction: Polyimide (PI) exhibits good biocompatibility and high mechanical strength, but biological inertness that does not stimulate bone regeneration, while laponite possesses excellent bioactivity. Methods: In this study, to improve the bioactivity of PI, nano-laponite ceramic (LC)-PI composites (LPCs) were fabricated by melt processing as implantable materials for bone repair. Results: The compressive strength, hydrophilicity, and surface roughness of LPCs with 40 w% LC content (LPC40s) were higher than LPC20s, and LPC20s higher than pure PI. In addition, no apatite mineralization occurred on PI, while apatite mineralized on LPCs in simulated body fluid. Compared with LPC20, more apatite deposited on LPC40, indicating good bioactivity. Moreover, the adhesion, proliferation, and alkaline phosphatase activity of rat bone mesenchymal stem cells on LPCs significantly increased with LC content increasing in vitro. Furthermore, the evaluations of animal experiments (micro-CT, histology, and pushout load) revealed that compared with LPC20 and PI, LPC40 significantly enhanced osteogenesis and osseointegration in vivo. Discussion: Incorporation of LC into PI obviously improved not only surface physicochemical properties but also biological properties of LPCs. LPC40 with high LC content displayed good biocompatibility and bioactivity, which markedly promoted osteogenesis and osseointegration. Therefore, with its superior biocompatibility and bioactivity, LPC40 could be an alternative candidate as an implant for orthopedic applications.


Assuntos
Apatitas/metabolismo , Materiais Biocompatíveis/farmacologia , Cerâmica/química , Imidas/química , Osseointegração/efeitos dos fármacos , Silicatos/química , Silicatos/farmacologia , Animais , Materiais Biocompatíveis/química , Regeneração Óssea/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanoestruturas/química , Osteogênese/efeitos dos fármacos , Ratos , Propriedades de Superfície
9.
Chem Biol Interact ; 332: 109305, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33130048

RESUMO

Erythrocytes (RBCs) represent the main cell component in circulation and recently have become a topic of intensive scientific interest. The relevance of erythrocytes as a model for cytotoxicity screening of xenobiotics is under the spotlight of this review. Erythrocytes constitute a fundamental cellular model to study potential interactions with blood components of manifold novel polymer or biomaterials. Morphological changes, subsequent disruption of RBC membrane integrity, and hemolysis could be used to determine the cytotoxicity of various compounds. Erythrocytes undergo a programmed death (eryptosis) which could serve as a good model for evaluating certain mechanisms which correspond to apoptosis taking place in nucleated cells. Importantly, erythrocytes can be successfully used as a valuable cellular model in examination of oxidative stress generated by certain diseases or multiple xenobiotics since red cells are subjected to permanent oxidative stress. Additionally, the antioxidant capacity of erythrocytes, and the activity of anti-oxidative enzymes could reflect reactive oxygen species (ROS) generating properties of various substances and allow to determine their effects on tissues. The last part of this review presents the latest findings on the possible application of RBCs as drug delivery systems (DDS). In conclusion, all these findings make erythrocytes highly valuable cells for in vitro biocompatibility assessment, cytotoxicity screening of a wide variety of substances as well as drug delivery.


Assuntos
Materiais Biocompatíveis/farmacologia , Sistemas de Liberação de Medicamentos , Eritrócitos/metabolismo , Xenobióticos/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Eriptose/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Humanos
10.
PLoS One ; 15(11): e0242274, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33216792

RESUMO

Various incurable eye diseases in companion animals often result in phthisis bulbi and eye removal surgery. Currently, the evisceration method using silicone balls is useful in animals; however, it is not available to those with impaired cornea or severe ocular atrophy. Moreover, ocular implant and prostheses are not widely used because of the diversity in animal size and eye shape, and high manufacturing cost. Here, we produced low-cost and customized artificial eyes, including implant and prosthesis, using computer-aided design and three-dimensional (3D) printing technique. For 3D modeling, the size of the artificial eyes was optimized using B-mode ultrasonography. The design was exported to STL files, and then printed using polycaprolactone (PCL) for prosthesis and mixture of PCL and hydroxyapatite (HA) for ocular implant. The 3D printed artificial eyes could be produced in less than one and half hour. The prosthesis was painted using oil colors and biocompatible resin. Two types of eye removal surgery, including evisceration and enucleation, were performed using two beagle dogs, as a preliminary study. After the surgery, the dogs were clinically evaluated for 6 months and then histopathological evaluation of the implant was done. Ocular implant was biocompatible and host tissue ingrowth was induced after in vivo application. The custom-made prosthesis was cosmetically excellent. Although long-term clinical follow-up might be required, the use of 3D printed-customized artificial eyes may be beneficial for animals that need personalized artificial eye surgery.


Assuntos
Olho Artificial , Impressão Tridimensional , Animais , Materiais Biocompatíveis/química , Desenho Assistido por Computador , Cães , Durapatita/química , Enucleação Ocular/veterinária , Feminino , Masculino , Poliésteres/química , Desenho de Prótese/veterinária , Implantação de Prótese/veterinária , Ultrassonografia
11.
Chirurgia (Bucur) ; 115(5): 650-655, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33138902

RESUMO

Introduction: Advanced pelvic organ prolapse is a public health problem, and its treatment can be difficult, requiring a multidisciplinary approach. Aim: The main objective of this article is to describe particular aspects of the use of Parietex ProGrip trade; Self-Fixating Mesh for abdominal sacrocolpopexy or sacrocervicopexy. The secondary objective is to present the initial results of the use of these self-fixating meshes. Results: Ten successive patients with a POP of grade 2 or higher have benefited from this procedure. No complications or recurrences of prolapse were detected at 1, 3 and 6 months postoperatively. The mean operative time was 102Â+-25.84 minutes. The mean length of hospital stay was 6.7Â+-0.67 days. Conclusions: The results of this surgical procedure demonstrate that Parietex ProGrip trade; Self- Fixating Mesh can be used without complications and with good postoperative results. The main advantage of using this mesh is that it does not require other fastening means. The lack of rejection reaction or foreign body pathology encourages the implementation of this surgical procedure. Further study is needed to consolidate these results.


Assuntos
Prolapso de Órgão Pélvico , Telas Cirúrgicas , Materiais Biocompatíveis , Colágeno , Feminino , Humanos , Prolapso de Órgão Pélvico/cirurgia , Poliésteres , Resultado do Tratamento
12.
An Acad Bras Cienc ; 92(4): e20191584, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206788

RESUMO

In this work, the natural latex extracted from Harconia speciosa was incorporated with silver nanoparticles (AgNP) to compose a functional biomaterial associating the intrinsic angiogenic activity of the latex and the antimicrobial activity of AgNP. Tissue reaction after subcutaneous implantation in dorsum of rats of membranes without AgNP and with 0.05%, 0.4% AgNP was compared at 3, 7 and 25 days. No statistically significant difference in the tissue response of the different biomaterials was observed, indicating that AgNP did not interfere with the inflammatory reaction (p > 0.05) or with the angiogenic activity of latex. Biomembranes were also tested against bacterial biofilm formation by Staphylococcus aureus and the antimicrobial activity of the new biomaterial can be found with bacteria crenation (0.05% AgNP) and no biofilm deposition (0.4% AgNP). Therefore, this biomaterial has interesting properties for the tissue repair process and may be feasible for future applications as dressing.


Assuntos
Látex , Nanopartículas Metálicas , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Biofilmes , Ratos , Prata/farmacologia
13.
Bone Joint J ; 102-B(12): 1646-1653, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33249906

RESUMO

AIMS: Vitamin E-infused highly crosslinked polyethylene (VEPE) has been introduced into total hip arthroplasty (THA) with the aim of further improving the wear characteristics of moderately and highly crosslinked polyethylenes (ModXLPE and HXLPE). There are few studies analyzing the outcomes of vitamin E-infused components in cemented arthroplasty, though early acetabular component migration has been reported. The aim of this study was to measure five-year polyethylene wear and acetabular component stability of a cemented VEPE acetabular component compared with a ModXLPE cemented acetabular component. METHODS: In a prospective randomized controlled trial (RCT), we assessed polyethylene wear and acetabular component stability (primary outcome) with radiostereometric analysis (RSA) in 68 patients with reverse hybrid THA at five years follow-up. Patients were randomized to either a VEPE or a ModXLPE cemented acetabular component. RESULTS: Mean polyethylene wear in the proximal direction was 0.17 mm (SD 0.15) for the VEPE group and 0.20 mm (SD 0.09) for the ModXLPE group (p = 0.005) at five years. Annual proximal wear rates were 0.03 mm/year (VEPE) and 0.04 mm/year (ModXLPE). Total 3D wear was 0.21 mm (SD 0.26) and 0.23 mm (SD 0.10) for the VEPE and ModXLPE groups, respectively (p = 0.009). Total 3D cup translation was 0.72 mm (SD 0.70) (VEPE) and 0.50 mm (SD 0.44) (ModXLPE) (p = 0.409). CONCLUSION: At five years, there was less polyethylene wear in the VEPE group than in the ModXLPE group. Both VEPE and ModXLPE cemented components showed low annual wear rates. Component stability was similar in the two groups and remained constant up to five years. Whether these results will equate to a lower long-term revision rate is still unknown. Cite this article: Bone Joint J 2020;102-B(12):1646-1653.


Assuntos
Artroplastia de Quadril/métodos , Materiais Biocompatíveis , Prótese de Quadril , Osteoartrite do Quadril/cirurgia , Polietileno , Acetábulo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/instrumentação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desenho de Prótese , Falha de Prótese , Análise Radioestereométrica , Vitamina E
14.
Nat Commun ; 11(1): 5696, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173046

RESUMO

Poorly immunogenic tumors, including triple negative breast cancers (TNBCs), remain resistant to current immunotherapies, due in part to the difficulty of reprogramming the highly immunosuppressive tumor microenvironment (TME). Here we show that peritumorally injected, macroporous alginate gels loaded with granulocyte-macrophage colony-stimulating factor (GM-CSF) for concentrating dendritic cells (DCs), CpG oligonucleotides, and a doxorubicin-iRGD conjugate enhance the immunogenic death of tumor cells, increase systemic tumor-specific CD8 + T cells, repolarize tumor-associated macrophages towards an inflammatory M1-like phenotype, and significantly improve antitumor efficacy against poorly immunogenic TNBCs. This system also prevents tumor recurrence after surgical resection and results in 100% metastasis-free survival upon re-challenge. This chemo-immunotherapy that concentrates DCs to present endogenous tumor antigens generated in situ may broadly serve as a facile platform to modulate the suppressive TME, and enable in situ personalized cancer vaccination.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Imunoterapia/métodos , Neoplasias de Mama Triplo Negativas/terapia , Animais , Antígenos de Neoplasias/metabolismo , Biotecnologia/métodos , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Fatores Imunológicos/metabolismo , Fatores Imunológicos/uso terapêutico , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias de Mama Triplo Negativas/imunologia , Microambiente Tumoral/imunologia
15.
Bone Joint J ; 102-B(11): 1527-1534, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33135435

RESUMO

AIMS: Vitamin E-infused highly cross-linked polyethylene (E1) has recently been introduced in total knee arthroplasty (TKA). An in vitro wear simulator study showed that E1 reduced polyethylene wear. However there is no published information regarding in vivo wear. Previous reports suggest that newly introduced materials which reduce in vitro polyethylene wear do not necessarily reduce in vivo polyethylene wear. To assist in the evaluation of the newly introduced material before widespread use, we established an in vivo polyethylene wear particle analysis for TKA. The aim of this study was to compare in vivo polyethylene wear particle generation between E1 and conventional polyethylene (ArCom) in TKA. METHODS: A total of 34 knees undergoing TKA (17 each with ArCom or E1) were investigated. Except for the polyethylene insert material, the prostheses used for both groups were identical. Synovial fluid was obtained at a mean of 3.4 years (SD 1.3) postoperatively. The in vivo polyethylene wear particles were isolated from the synovial fluid using a previously validated method and examined by scanning electron microscopy. RESULTS: The total number of polyethylene wear particles obtained from the knees with E1 (mean 6.9, SD 4.0 × 107 counts/knee) was greater than that obtained from those with ArCom (mean 2.2, SD 2.6 × 107 counts/knee) (p = 0.001). The particle size (equivalent circle of diameter) from the knees with E1 was smaller (mean 0.5 µm, SD 0.1) than that of knees with ArCom (mean 1.5, SD 0.3 µm) (p = 0.001). The aspect ratio of particles from the knees with E1 (mean 1.3, SD 0.1) was smaller than that with ArCom (mean 1.4, SD 0.1) (p < 0.001 ). CONCLUSION: This is the first report of in vivo wear particle analysis of E1. E1 polyethylene did not reduce the number of in vivo polyethylene wear particles compared with ArCom in early clinical stage. Further careful follow-up of newly introduced E1 for TKA should be carried out. Cite this article: Bone Joint J 2020;102-B(11):1527-1534.


Assuntos
Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/instrumentação , Prótese do Joelho/efeitos adversos , Falha de Prótese , Líquido Sinovial/química , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis/análise , Humanos , Polietileno/análise , Falha de Prótese/etiologia , Vitamina E
16.
Braz Dent J ; 31(5): 477-484, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33146330

RESUMO

This study evaluated the biocompatibility, biomineralization, and collagen fiber maturation induced by Resorbable Tissue Replacement (RTR®; ß-tricalcium phosphate [TCP]), Bioglass (BIOG; bioactive glass), and DM Bone® (DMB; hydroxyapatite and ß-TCP) in vivo. Sixty-four polyethylene tubes with or without (control group; CG) materials (n=8/group/period) were randomly implanted in the subcutaneous tissue of 16 male Wistar rats (four per rat), weighting 250 to 280 g. The rats were killed after 7 and 30 days (n=8), and the specimens were removed for analysis of inflammation using hematoxylin-eosin; biomineralization assay using von Kossa (VK) staining and polarized light (PL); and collagen fiber maturation using picrosirius red (PSR). Nonparametric data were statistically analyzed by Kruskal-Wallis and Dunn tests, and parametric data by one-way ANOVA test (p<0.05). At 7 days, all groups induced moderate inflammation (p>0.05). At 30 days, there was mild inflammation in the BIOG and CG, and moderate inflammation in the RTR and DMB groups, with a significant difference between the CG and RTR (p<0.05). The fibrous capsule was thick at 7 days and predominantly thin at 30 days in all groups. All materials exhibited structures that stained positively for VK and PL. Immature collagen fibers were predominant at 7 and 30 days in all groups (p>0.05), although DMB exhibited more mature fibers than BIOG at 30 days (p<0.05). RTR, BIOG, and DMB were biocompatible, inducing inflammation that reduced over time and biomineralization in the subcutaneous tissue of rats. DMB exhibited more mature collagen fibers than BIOG over a longer period.


Assuntos
Biomineralização , Materiais Restauradores do Canal Radicular , Compostos de Alumínio , Animais , Materiais Biocompatíveis , Compostos de Cálcio , Cerâmica , Colágeno , Masculino , Teste de Materiais , Óxidos , Ratos , Ratos Wistar , Silicatos , Tela Subcutânea
17.
Int J Nanomedicine ; 15: 8465-8478, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149587

RESUMO

Introduction: Decellularized matrix from porcine small intestinal submucosa (SIS) endows scaffolds with an ECM-like surface, which enhances stem cell self-renewal, proliferation, and differentiation. Mesoporous bioactive glass (MBG) is extensively recognized as an excellent bio-ceramic for fabricating bone grafts. Materials and Methods: In the current study, SIS was doped on an MBG scaffold (MBG/SIS) using polyurethane foam templating and polydopamine chemistry method. To mimic the bony environment of a natural bone matrix, an ECM-inspired delivery system was constructed by coupling the BMP2-related peptide P28 to a heparinized MBG/SIS scaffold (MBG/SIS-H-P28). The release of P28 from MBG/SIS-H-P28 and its effects on the proliferation, viability, and osteogenic differentiation of bone marrow stromal stem cells were investigated in vitro and in vivo. Results: Our research indicated that the novel tissue-derived ECM scaffold MBG/SIS has a hierarchical and interconnected porous architecture, and superior biomechanical properties. MBG/SIS-H-P28 released P28 in a controlled manner, with the long-term release time of 40 d. The results of in vitro experiments showed improvements in cell proliferation, cell viability, alkaline phosphatase activity, and mRNA expression levels of osteogenesis-related genes (Runx-2, OCN, OPN, and ALP) compared to those of MBG/SIS or MBG/SIS-P28 and MBG/SIS-H-P28. The in vivo results demonstrated that MBG/SIS-H-P28 scaffolds evidently increased bone formation in rat calvarial critical-sized defect compared to that in controls. Conclusion: MBG/SIS-H-P28 scaffolds show potential as ideal platforms for delivery of P28 and for providing a bony environment for bone regeneration.


Assuntos
Ácido Aspártico/química , Materiais Biocompatíveis/farmacologia , Proteína Morfogenética Óssea 2/farmacologia , Osso e Ossos/efeitos dos fármacos , Cerâmica/farmacologia , Matriz Extracelular/metabolismo , Osteoblastos/efeitos dos fármacos , Peptídeos/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Cinética , Masculino , Camundongos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Porosidade , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Suínos , Tecidos Suporte/química
18.
Nat Commun ; 11(1): 5967, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33235277

RESUMO

Practically applied techniques for ultrasonic biomedical imaging employ delay-and-sum (DAS) beamforming which can resolve two objects down to 2.1λ within the acoustic Fresnel zone. Here, we demonstrate a phononic metamaterial lens (ML) for detection of laterally subwavelength object features in tissue-like phantoms beyond the phononic crystal evanescent zone and Fresnel zone of the emitter. The ML produces metamaterial collimation that spreads 8x less than the emitting transducer. Utilizing collimation, 3.6x greater lateral resolution beyond the Fresnel zone limit was achieved. Both hard objects and tissue approximating masses were examined in gelatin tissue phantoms near the Fresnel zone limit. Lateral dimensions and separation were resolved down to 0.50λ for hard objects, with tissue approximating masses slightly higher at 0.73λ. The work represents the application of a metamaterial for spatial characterization, and subwavelength resolution in a biosystem beyond the Fresnel zone limit.


Assuntos
Materiais Biocompatíveis , Cristalino , Imagens de Fantasmas , Ultrassonografia/métodos , Engenharia Biomédica/métodos , Processamento de Imagem Assistida por Computador/métodos
19.
Int J Nanomedicine ; 15: 5991-6006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192060

RESUMO

Owing to the unique physical, chemical, mechanical and electrical properties, graphene and its derivatives have been extensively researched for diverse biomedical applications including in tissue engineering since the past decade. Tunable chemical functionalities of graphene oxide (GO), a graphene derivative, allow easy surface functionalization. Functionalization of GO with poly(ethylene glycol) (PEG) (PEG-GO) has received significant attention as it offers superior solubility, stability, and biocompatibility. Besides being an attractive candidate for drug delivery, PEG-GO can aid in the attachment, proliferation, and differentiation of stem cells, thereby augmenting tissue engineering. PEG-GO has shown excellent antibacterial efficacy, which could be an added advantage to minimize implant-associated infections. This review describes the synthesis techniques, properties, and biological potential of PEG-GO towards mammalian and bacterial cells. Studies wherein these nanomaterials have been explored for engineering various tissues are reviewed along with future opportunities in this field.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Grafite/química , Engenharia Tecidual/métodos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis , Diferenciação Celular , Teoria da Densidade Funcional , Humanos , Simulação de Dinâmica Molecular , Nanoestruturas/química , Polietilenoglicóis/química , Solubilidade , Células-Tronco
20.
Sci Rep ; 10(1): 16671, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028837

RESUMO

Visually significant corneal injuries and subsequent scarring collectively represent a major global human health challenge, affecting millions of people worldwide. Unfortunately, less than 2% of patients who could benefit from a sight-restoring corneal transplant have access to cadaveric donor corneal tissue. Thus, there is a critical need for new ways to repair corneal defects that drive proper epithelialization and stromal remodeling of the wounded area without the need for cadeveric donor corneas. Emerging therapies to replace the need for donor corneas include pre-formed biosynthetic buttons and in situ-forming matrices that strive to achieve the transparency, biocompatibility, patient comfort, and biointegration that is possible with native tissue. Herein, we report on the development of an in situ-forming hydrogel of collagen type I crosslinked via multi-functional polyethylene glycol (PEG)-N-hydroxysuccinimide (NHS) and characterize its biophysical properties and regenerative capacity both in vitro and in vivo. The hydrogels form under ambient conditions within minutes upon mixing without the need for an external catalyst or trigger such as light or heat, and their transparency, degradability, and stiffness are modulated as a function of number of PEG arms and concentration of PEG. In addition, in situ-forming PEG-collagen hydrogels support the migration and proliferation of corneal epithelial and stromal cells on their surface. In vivo studies in which the hydrogels were formed in situ over stromal keratectomy wounds without sutures showed that they supported multi-layered surface epithelialization. Overall, the in situ forming PEG-collagen hydrogels exhibited physical and biological properties desirable for a corneal stromal defect wound repair matrix that could be applied without the need for sutures or an external trigger such as a catalyst or light energy.


Assuntos
Materiais Biocompatíveis/química , Colágeno Tipo I/química , Lesões da Córnea/terapia , Hidrogéis/química , Polietilenoglicóis/química , Animais , Ceratectomia , Coelhos
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