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1.
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
2.
Bone Joint J ; 102-B(2): 191-197, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32009430

RESUMO

AIMS: Although good clinical outcomes have been reported for monolithic tapered, fluted, titanium stems (TFTS), early results showed high rates of subsidence. Advances in stem design may mitigate these concerns. This study reports on the use of a current monolithic TFTS for a variety of indications. METHODS: A multi-institutional retrospective study of all consecutive total hip arthroplasty (THA) and revision total hip arthroplasty (rTHA) patients who received the monolithic TFTS was conducted. Surgery was performed by eight fellowship-trained arthroplasty surgeons at four institutions. A total of 157 hips in 153 patients at a mean follow-up of 11.6 months (SD7.8) were included. Mean patient age at the time of surgery was 67.4 years (SD 13.3) and mean body mass index (BMI) was 28.9 kg/m2 (SD 6.5). Outcomes included intraoperative complications, one-year all-cause re-revisions, and subsidence at postoperative time intervals (two weeks, six weeks, six months, nine months, and one year). RESULTS: There were eight intraoperative complications (4.9%), six of which were intraoperative fractures; none occurred during stem insertion. Six hips (3.7%) underwent re-revision within one year; only one procedure involved removal of the prosthesis due to infection. Mean total subsidence at latest follow-up was 1.64 mm (SD 2.47). Overall, 17 of 144 stems (11.8%) on which measurements could be performed had >5 mm of subsidence, and 3/144 (2.1%) had >10 mm of subsidence within one year. A univariate regression analysis found that additional subsidence after three months was minimal. A multivariate regression analysis found that subsidence was not significantly associated with periprosthetic fracture as an indication for surgery, the presence of an extended trochanteric osteotomy (ETO), Paprosky classification of femoral bone loss, stem length, or type of procedure performed (i.e. full revision vs conversion/primary). CONCLUSION: Advances in implant design, improved trials, a range of stem lengths and diameters, and high offset options mitigate concerns of early subsidence and dislocation with monolithic TFTS, making them a valuable option for femoral revision. Cite this article: Bone Joint J 2020;102-B(2):191-197.


Assuntos
Artroplastia de Quadril/instrumentação , Articulação do Quadril/cirurgia , Prótese de Quadril , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Materiais Biocompatíveis , Fêmur/fisiopatologia , Fêmur/cirurgia , Articulação do Quadril/fisiopatologia , Prótese de Quadril/efeitos adversos , Humanos , Pessoa de Meia-Idade , Osseointegração , Desenho de Prótese , Reoperação/instrumentação , Estudos Retrospectivos , Titânio , Resultado do Tratamento
3.
Bone Joint J ; 102-B(2): 170-176, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32009432

RESUMO

AIMS: We aimed to examine the long-term mechanical survivorship, describe the modes of all-cause failure, and identify risk factors for mechanical failure of all-polyethylene tibial components in endoprosthetic reconstruction. METHODS: This is a retrospective database review of consecutive endoprosthetic reconstructions performed for oncological indications between 1980 and 2019. Patients with all-polyethylene tibial components were isolated and analyzed for revision for mechanical failure. Outcomes included survival of the all-polyethylene tibial component, revision surgery categorized according to the Henderson Failure Mode Classification, and complications and functional outcome, as assessed by the Musculoskeletal Tumor Society (MSTS) score at the final follow-up. RESULTS: A total of 278 patients were identified with 289 all-polyethylene tibial components. Mechanical survival was 98.4%, 91.1%, and 85.2% at five, ten and 15 years, respectively. A total of 15 mechanical failures were identified at the final follow-up. Of the 13 all-polyethylene tibial components used for revision of a previous tibial component, five (38.5%) failed mechanically. Younger patients (< 18 years vs > 18 years; p = 0.005) and those used as revision components (p < 0.001) had significantly increased rates of failure. Multivariate logistic regression modelling showed revision status to be a positive risk factor for failure (odds ratio (OR) 19.498, 95% confidence interval (CI) 4.598 to 82.676) and increasing age was a negative risk factor for failure (OR 0.927, 95% CI 0.872 to 0.987). Age-stratified risk analysis showed that age > 24 years was no longer a statistically significant risk factor for failure. The final mean MSTS score for all patients was 89% (8.5% to 100.0%). CONCLUSION: The long-term mechanical survivorship of all-polyethylene tibial components when used for tumour endoprostheses was excellent. Tumour surgeons should consider using these components for their durability and the secondary benefits of reduced cost and ease of removal and revision. However, caution should be taken when using all-polyethylene tibial components in the revision setting as a significantly higher rate of mechanical failure was seen in this group of patients. Cite this article: Bone Joint J. 2020;102-B(2):170-176.


Assuntos
Neoplasias Ósseas/cirurgia , Fêmur/cirurgia , Próteses e Implantes/efeitos adversos , Implantação de Prótese/efeitos adversos , Tíbia/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis , Criança , Análise de Falha de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Polietileno , Desenho de Prótese , Falha de Prótese/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Adulto Jovem
4.
Bone Joint J ; 102-B(2): 220-226, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32009425

RESUMO

AIMS: Arthroplasty for end-stage hallux rigidus (HR) is controversial. Arthrodesis remains the gold standard for surgical treatment, although is not without its complications, with rates of up to 10% for nonunion, 14% for reoperation and 10% for metatarsalgia. The aim of this study was to analyze the outcome of a double-stemmed silastic implant (Wright-Medical, Memphis, Tennessee, USA) for patients with end-stage HR. METHODS: We conducted a retrospective review of 108 consecutive implants in 76 patients, between January 2005 and December 2016, with a minimum follow-up of two years. The mean age of the patients at the time of surgery was 61.6 years (42 to 84). There were 104 females and four males. Clinical, radiological, patient reported outcome measures (PROMS) data, a visual analogue score (VAS) for pain, and satisfaction scores were collected. RESULTS: The survivorship at a mean follow-up of 5.3 years (2.1 to 14.1) was 97.2%. The mean Manchester Oxford Foot and Ankle Questionnaire (MOXFQ) scores improved from 78.1 to 11.0, and VAS scores for pain from 7/10 to 1.3/10. The rate of satisfaction was 90.6%. Three implants (2.8%) required revision; one for infection, one-month postoperatively, and two for stem breakage at 10.4 and 13.3 years postoperatively. There was a 1.9% reoperation rate other than revision, 23.1% of patients developed a minor complication, and 21.1% of patients had non-progressive and asymptomatic cysts on radiological review. CONCLUSION: We report a 97.2% survivorship at a mean follow-up of 5.3 years with this implant. We did not find progressive osteolysis, as has been previously reported. These results suggest that this double-stemmed silastic implant provides a predictable and reliable alternative with comparable outcomes to arthrodesis for the treatment of end-stage HR. Cite this article: Bone Joint J 2020;102-B(2):220-226.


Assuntos
Artroplastia de Substituição/métodos , Hallux Rigidus/cirurgia , Prótese Articular , Articulação Metatarsofalângica/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis , Dimetilpolisiloxanos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
J Biomed Nanotechnol ; 16(1): 101-110, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31996289

RESUMO

Large (> 6 mm) artificial blood vessels have been successfully employed in clinic practice. However, small-diameter (< 6 mm) synthetic grafts have not been applied due to their hydrophobicity. In this study, poly-vinylpyrrolidone (PVP) was introduced into poly-L-lactic acid (PLLA) to prepare biodegradable small-diameter electrospun blood vessels which were further modified via electrostatic self-assembly (ESA). The characteristics of PLLA/PVP films were investigated by scanning electron microscopy (SEM), contact angle measurement and mechanical property testing. The cytocompatiblility and blood compatibility of the fiber films were further studied through vascular smooth muscle cells (VSMCs) proliferation and platelet adhesion, and the morphology of cells on films was viewed by laser scanning confocal microscopy (LSCM) and SEM. Next, the surface of ESA-modified electrospun fiber films was analyzed through SEM and photoelectron spectroscopy (XPS). The degradation characteristics of these films were investigated through SEM observation, weight loss, viscosity average molecular weight reduction, and pH change in the testing solutions as well. The films were also subcutaneously implanted in rabbits to analyze the biocompatibility. The results of these experiments showed that electrospun films with PVP possessed a good structure and improved hydrophilicity. The films assembled with chitosan/heparin by ESA were beneficial to VSMCs survival and had excellent blood compatibilities. The data indicated these films were biodegradable with good tissue compatibility. In conclusion, we successfully obtained biodegradable small-diameter blood vessels through electrospinning PLLA/PVP and modifying this blend's surface using ESA. The study provided a feasible method for making small-diameter synthetic blood vessels with improved hydrophilic and anticoagulant properties.


Assuntos
Substitutos Sanguíneos/química , Animais , Materiais Biocompatíveis , Quitosana , Poliésteres , Polímeros , Coelhos , Propriedades de Superfície
6.
J Appl Oral Sci ; 28: e20190215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939521

RESUMO

OBJECTIVE: This study evaluated the angiogenesis-enhancing potential of a tricalcium silicate-based mineral trioxide aggregate (ProRoot MTA), Biodentine, and a novel bioceramic root canal sealer (Well-Root ST) in human dental pulp stem cells (hDPSCs), human periodontal ligament stem cells (hPLSCs), and human tooth germ stem cells (hTGSCs). METHODOLOGY: Dulbecco's modified Eagle's medium was conditioned for 24 h by exposure to ProRoot MTA, Biodentine, or Well-Root ST specimens (prepared according to the manufacturers' instructions). The cells were cultured in these conditioned media and their viability was assessed with 3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfo-phenyl)-2H tetrazolium (MTS) on days 1, 3, 7, 10, and 14. Angiogenic growth factors [platelet-derived growth factor (PDGF), basic fibroblast growth factor (FGF-2), and vascular endothelial growth factor (VEGF)] were assayed by sandwich enzyme-linked immunosorbent assay (ELISA) on days 1, 7, and 14. Human umbilical vein endothelial cell (HUVEC) migration assays were used to evaluate the vascular effects of the tested materials at 6-8 h. Statistical analyses included Kruskal-Wallis, Mann-Whitney U, and Friedman and Wilcoxon signed rank tests. RESULTS: None of tricalcium silicate-based materials were cytotoxic and all induced a similar release of angiogenic growth factors (PDGF, FGF-2, and VEGF) (p>0.05). The best cell viability was observed for hDPSCs (p<0.05) with all tricalcium silicate-based materials at day 14. Tube formation by HUVECs showed a significant increase with all tested materials (p<0.05). CONCLUSION: The tricalcium silicate-based materials showed potential for angiogenic stimulation of all stem cell types and significantly enhanced tube formation by HUVECs.


Assuntos
Indutores da Angiogênese/farmacologia , Compostos de Cálcio/farmacologia , Cerâmica/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/farmacologia , Células-Tronco/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Fator 2 de Crescimento de Fibroblastos/análise , Fator 2 de Crescimento de Fibroblastos/efeitos dos fármacos , Citometria de Fluxo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Teste de Materiais , Neovascularização Fisiológica/efeitos dos fármacos , Ligamento Periodontal/citologia , Ligamento Periodontal/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/análise , Fator de Crescimento Derivado de Plaquetas/efeitos dos fármacos , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Germe de Dente/citologia , Germe de Dente/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos
7.
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
8.
Chem Commun (Camb) ; 56(3): 399-402, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31820751

RESUMO

A combinatorial approach using a one-bead-one-compound method and a screening based on a SOD-activity assay was set up for the discovery of an efficient peptidyl copper complex. The complex exhibited good stability constants, suitable redox potentials and excellent intrinsic activity. This complex was further assayed in cells for its antioxidant properties and showed beneficial effects when cells were subjected to oxidative stress.


Assuntos
Materiais Biocompatíveis/metabolismo , Cobre/química , Peptídeos/química , Sequência de Aminoácidos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Colo/citologia , Colo/efeitos dos fármacos , Colo/metabolismo , Cobre/metabolismo , Células HT29 , Humanos , Interleucina-8/metabolismo , Lipopolissacarídeos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/metabolismo , Superóxido Dismutase/metabolismo
9.
J Photochem Photobiol B ; 202: 111715, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790882

RESUMO

Biomimetic gold nanoparticles of biological origin have created a significant impact on the field of biomedicine due to the great expectations of its applications. Because of this, the influences of biomimetic gold nanoparticles have been immensely studied, targeting various cancer cells. However, the impact of biomimetic gold nanoparticles against normal non-cancerous cells is scanty, which impose several limitations in their utility. Taking this as a challenge, we in this study report the biomimetic gold nanoparticles from marine seaweed Gelidium pusillum (G. pusillum) to evaluate its cytotoxic and biocompatible ability evidenced by fluorescence-based assays in cultured cells. The gold nanoparticles obtained in the study were spherical shaped with a mean diameter of 12 ± 4.2 nm. The seaweed extract plays a crucial role in stabilizing the gold nanoparticles to avoid aggregation and coalescence. At an IC50 concentration of 43.09 ± 1.6 µgmL-1, the biomimetic gold nanoparticles were found to be toxic to cancerous cells (MDA-MB-231). Whereas, biomimetic gold nanoparticles exhibit significant biocompatibility with human embryonic kidney cells even at a higher concentration of 150 µgmL-1. The morphological based fluorescence assays confirmed the ability of biomimetic gold nanoparticles in inducing apoptosis and thereby kills cancer cells. Altogether, the gold nanoparticles were safe to normal cells and did not show a significant impact. Hence, the novel biomimetic gold nanoparticles hold potential as multifaceted agent and can further be taken up to various biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Ouro/química , Nanopartículas Metálicas/química , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Química Verde , Células HEK293 , Humanos , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Alga Marinha/química , Alga Marinha/metabolismo
10.
J Appl Oral Sci ; 28: e20190023, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31800871

RESUMO

When exposure of the pulp to external environment occurs, reparative dentinogenesis can be induced by direct pulp capping to maintain pulp tissue vitality and function. These clinical situations require the use of materials that induce dentin repair and, subsequently, formation of a mineralized tissue. OBJECTIVE: This work aims to assess the effect of tricalcium silicate cements and mineral trioxide aggregate cements, including repairing dentin formation and inflammatory reactions over time after pulp exposure in Wistar rats. METHODOLOGY: These two biomaterials were compared with positive control groups (open cavity with pulp tissue exposure) and negative control groups (no intervention). The evaluations were performed in three stages; three, seven and twenty-one days, and consisted of an imaging (nuclear medicine) and histological evaluation (H&E staining, immunohistochemistry and Alizarin Red S). RESULTS: The therapeutic effect of these biomaterials was confirmed. Nuclear medicine evaluation demonstrated that the uptake of 99mTc-Hydroxymethylene diphosphonate (HMDP) showed no significant differences between the different experimental groups and the control, revealing the non-occurrence of differences in the phosphocalcium metabolism. The histological study demonstrated that in mineral trioxide aggregate therapies, the presence of moderate inflammatory infiltration was found after three days, decreasing during follow-ups. The formation of mineralized tissue was only verified at 21 days of follow-up. The tricalcium silicate therapies demonstrated the presence of a slight inflammatory infiltration on the third day, increasing throughout the follow-up. The formation of mineralized tissue was observed in the seventh follow-up day, increasing over time. CONCLUSIONS: The mineral trioxide aggregate (WhiteProRoot®MTA) and tricalcium silicate (Biodentine™) present slight and reversible inflammatory signs in the pulp tissue, with the formation of mineralized tissue. However, the exacerbated induction of mineralized tissue formation with the tricalcium silicate biomaterial may lead to the formation of pulp calcifications.


Assuntos
Compostos de Alumínio/farmacologia , Materiais Biocompatíveis/farmacologia , Compostos de Cálcio/farmacologia , Polpa Dentária/efeitos dos fármacos , Dentina/efeitos dos fármacos , Dentinogênese/efeitos dos fármacos , Óxidos/farmacologia , Silicatos/farmacologia , Animais , Polpa Dentária/patologia , Capeamento da Polpa Dentária/métodos , Exposição da Polpa Dentária/tratamento farmacológico , Exposição da Polpa Dentária/patologia , Combinação de Medicamentos , Proteínas da Matriz Extracelular/análise , Imuno-Histoquímica , Masculino , Imagem Molecular/métodos , Odontoblastos/efeitos dos fármacos , Fosfoproteínas/análise , Agentes de Capeamento da Polpa Dentária e Pulpectomia/farmacologia , Pulpite/tratamento farmacológico , Pulpite/patologia , Distribuição Aleatória , Ratos Wistar , Reprodutibilidade dos Testes , Sialoglicoproteínas/análise , Fatores de Tempo
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 Photochem Photobiol B ; 202: 111669, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31739258

RESUMO

Herein we report the synthesis and characterization of the antifouling Gadolinium oxide (Gd2O3) nanoparticles (NPs) modified with PEG with improved biocompatibility for MR imaging purposes. In this report, using the solvothermal decomposition of Gadolinium (III) in the presence of Na3cit, monitored by surface modification with PEG and L-Cys. The synthesized nanoparticles were confirmed by the TEM, DLS and UV-Visible spectroscopy. The morphological results show normal distance across of the flawless Gd2O3-PEG-Cys-NPs show 7.9 ±â€¯0.4 nm, discretely, with a thin size exchange. This infers the surface adjustment does not obviously alteration the center size of the Gd2O3-NPs when contrasted with the perfect sodium citrate-balanced out Gd2O3-NPs. The Gd2O3-PEG-L-Cys-NPs are highly stable at room temperature, water dispersible and importantly less cytotoxic at high concentration of the NPs. The T1-weighted MR phantasm readings evidentially displayed that the formed PEG coated Gd2O3-PEG and Gd2O3-PEG-Cys-NPs with and without Cys may be performed as the promising T1-weighted MR imaging. The NPs displays no signs of toxicity against the human blood, which represents the biocompatibility for the human medicine applications. The Gd2O3-PEG-Cys-NPs shows relatively, high r1 acceptable cytocompatibility, target specific cancer cells and activate the dual mode MR imaging of lung metastasis cancer model in vitro. The development of versatile zwitterion functionalized Gd2O3 may be promising as an active nanoparticle probe for improved multi-model of MR imaging agents for various cancer diseases.


Assuntos
Meios de Contraste/química , Gadolínio/química , Neoplasias Pulmonares/diagnóstico por imagem , Imagem por Ressonância Magnética , Nanopartículas/química , Polietilenoglicóis/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisteína/química , Hemólise/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/secundário , Melanoma Experimental/patologia , Camundongos , Nanopartículas/toxicidade , Células RAW 264.7 , Transplante Homólogo
14.
Phys Chem Chem Phys ; 22(3): 985-996, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31829369

RESUMO

Owing to their high saturation magnetisation, cobalt nanoparticles hold significant potential for the hyperthermia treatment of tumours. Covalent binding of carboxylic acids to the nanoparticles can induce biocompatibility, whilst also preventing the formation of surface oxides which reduce the magnetic properties of cobalt. Understanding the origin of the acid-metal interaction is key, yet probably the most experimentally challenging step, for the rational design of such entities. In this density functional theory study, we use static calculations to establish that a 57-atom Co cluster is the smallest model able to reproduce the adsorption behaviour of carboxylic acids, and ab initio metadynamics to obtain the structure and the free energy landscape for its interaction with valeric acid. Our simulations show that a bridging bidentate binding mode has a stronger affinity compared to monodentate binding, with energetically high transition barriers between the two. A chelate interaction mode of two carboxyl oxygen atoms can be formed as an intermediate. These results clarify the organic-inorganic interactions in the cobalt-acid system, providing a basis for the rational design of biocompatible metallic nanoparticles.


Assuntos
Ácidos Carboxílicos/química , Ácidos Carboxílicos/metabolismo , Cobalto/química , Nanopartículas Metálicas/química , Adsorção , Materiais Biocompatíveis/química , Simulação por Computador
15.
J Photochem Photobiol B ; 202: 111676, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31837583

RESUMO

Wounds origins serious complications of lives of human beings which may leads to death. The important issue for the problem is infection during wound care management which delays wound healing process. These kinds of infections may be caused by the overuse or misuse of antibiotics, antidotes, usage of new drugs, not properly sterilized surgical instruments, not appropriate for pH level and imperfect wound dressing etc. during or after surgery. Hence in this report, antimicrobial action of pH responsive TA/KA composited hydrogel crosslinked with GO-QDs (TA/KA-GOQDs) using citric acid as cross-linker has been reported by demonstrating in-vitro and in-vivo studies for wound care management. The prepared samples of GOQDs, TA/KA hydrogel and TA/KA-GOQDs were characterized using FT-IR, XRD, SEM and TEM techniques. pH responsive hydrogel property of TA/KA was evaluated by swelling studies. In-vitro antibacterial studies was carried out by direct contact test method. Further, the prepared samples were tested in a wound healing model of rate with the wound of size 1.5 cm2 for in-vivo studies. After 16 days of treatment, the prepared samples for wound healing causes 100% wound areas closure. Histological observations were made by MT and HE staining process which proves keratinocytes proliferation by biocompatible and biocomposited TA/KA-GOQDs. The pH responsive TA/KA-GOQDs proved as efficient wound healing agent by faster keratinocytes proliferation within a compact period.


Assuntos
Materiais Biocompatíveis/farmacologia , Grafite/química , Hidrogéis/química , Queratinas/química , Pontos Quânticos/química , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Queratinócitos/citologia , Queratinócitos/metabolismo , Ratos , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos
16.
Carbohydr Polym ; 227: 115338, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590863

RESUMO

New sources of AIE materials with good water solubility, biocompatibility, degradability, and mass production are urgently needed. Here, we found that chitosan, a very abundant polysaccharide in nature, has fluorescence emission in both solid and solution states with AIE effect, and explored its multifunctional applications. Chitosan can emit a variety of colors from blue to red at different excitation wavelengths with excellent multicolor imaging capabilities at the cellular level. Utilizing the cationic and antibacterial properties of chitosan, the quantification of bacteria can be achieved through the AIE effect. Concurrently, it can be used as fluorescent probes for multi-channel bacterial imaging via lighting-up bacteria. Furthermore, the chitosan solution exhibits a sensitive quenching response to Fe3+, which can be used as a biosensor for detecting the concentration of Fe3+. These interesting results indicate that chitosan will have broad application prospects as a new class of AIE material.


Assuntos
Materiais Biocompatíveis , Quitosana , Fluorescência , Escherichia coli , Humanos , Ferro , Células MCF-7 , Microscopia Confocal , Espectrometria de Fluorescência
17.
Chemistry ; 26(8): 1880-1886, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868256

RESUMO

N-(4-Nitrobenzoyl)-Phe self-assembled into a transparent supramolecular hydrogel, which displayed high fibroblast and keratinocyte cell viability. The compound showed a mild antimicrobial activity against E. coli both as a hydrogel and in solution. Single-crystal XRD data revealed packing details, including protonation of the C-terminus due to an apparent pKa shift, as confirmed by pH titrations. MicroRaman analysis revealed almost identical features between the gel and crystal states, although more disorder in the former. The hydrogel is thermoreversible and disassembles within a range of temperatures that can be fine-tuned by experimental conditions, such as gelator concentration. At the minimum gelling concentration of 0.63 wt %, the hydrogel disassembles in a physiological temperature range of 39-42 °C, thus opening the way to its potential use as a biomaterial.


Assuntos
Anti-Infecciosos/química , Materiais Biocompatíveis/química , Hidrogéis/química , Aminoácidos/química , Animais , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Humanos , Camundongos , Conformação Molecular , Células NIH 3T3
18.
Water Res ; 168: 115152, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31614240

RESUMO

The co-existence of multiple pollutants in wastewater such as nitrate and heavy metal, is of high concern due to the potential environmental impact. In this study, a novel biomaterial PPy@Fe3O4/PVA was synthesized as a multifunctional bacteria immobilized carrier, to enhance simultaneous denitrification, Cd(II) and Mn(II) removal efficiency in bioreactor environments. The morphology and main components of the PPy@Fe3O4/PVA material were characterized by SEM and XRD. Using PPy@Fe3O4/PVA as a carrier, the maximum removal efficiencies for nitrate (0.207 mg L-1·h-1), Mn(II) (90.98%) and Cd(II) (98.78%) were increased by 27.05%, 30.27%, and 16.48%, respectively, compared to in the absence of PPy@Fe3O4/PVA. Regeneration experiments were performed, demonstrating the excellent stability and reusability of the PPy@Fe3O4/PVA material. Furthermore, effects of key factors were investigated on the performance of the PPy@Fe3O4/PVA bioreactor in simultaneous denitrification, Mn(II) and Cd(II) removal. Experimental results indicate that the highest nitrate, Mn(II) and Cd(II) removal efficiencies were obtained under the conditions of HRT of 10 h, initial Mn(II) concentration of 40 mg/L and initial Cd(II) concentration of 10 mg/L. Gas chromatography analysis indicated that N2 was the mainly final gaseous product. Moreover, the bioreactor community diversity was markedly influenced by the initial concentration of Cd(II) and Pseudomonas sp. H117 played a primary role in the process of simultaneous denitrification, Mn(II) and Cd(II) removal.


Assuntos
Álcool de Polivinil , Poluentes Químicos da Água , Materiais Biocompatíveis , Reatores Biológicos , Cádmio , Desnitrificação , Nitratos
19.
J Colloid Interface Sci ; 558: 47-54, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31580954

RESUMO

The unique antibacterial characteristics of Ag nanomaterials offer a wide potential range of applications, but achieving rapid and durable antibacterial efficacy is challenging. This is because the speed and durability of the antibacterial function make conflicting demands on the structural design: the former requires the direct exposure of Ag to the surrounding environment, whereas the durability requires Ag to be protected from the environment. To overcome this incompatibility, we synthesize sandwich-structured polydopamine shells decorated both internally and externally with Ag nanoparticles, which exhibit prompt and lasting bioactivity in applications. These shells are biocompatible and can be used in vivo to counter bacterial infection caused by methicillin-resistant Staphylococcus aureus superbugs and to inhibit biofilm formation. This work represents a new paradigm for the design of composite materials with enhanced antibacterial properties.


Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Indóis/química , Nanopartículas Metálicas/química , Polímeros/química , Prata/química , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Ratos , Ratos Sprague-Dawley
20.
J Colloid Interface Sci ; 558: 137-144, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586733

RESUMO

Platinum oxide (PtOx) nanoparticles (NPs) have been shown to possess anticancer activity by releasing ionic Pt species under biological conditions. However, the dissolution kinetics and the changes in the chemical state of Pt during PtOx dissolution have not yet been studied. To fill this gap, we prepared a composite (designated as PtOx@MMT-2) containing PtOx NPs on hollow mesoporous silica nanospheres and studied the dissolution of the material in different biorelevant media. We found that the release of Pt was retarded due to the adsorption of biomolecules on PtOx NPs during the degradation of host silica. The biomolecules adsorption also lowered the accessibility of PtOx NPs, resulting in the reduced catalase-like activity of the NPs. In line with the results, the cytotoxicity of PtOx@MMT-2, which was positively correlated to the amount of Pt uptake, was reduced by biomolecules adsorption. Our findings should be applicable to other metal (oxide) NPs under biological conditions and may provide implications for the design of nanomaterials for practical therapeutic applications.


Assuntos
Materiais Biocompatíveis/química , Nanopartículas/química , Óxidos/química , Platina/química , Dióxido de Silício/química , Adsorção , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Nanopartículas/uso terapêutico , Solubilidade
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