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In recent years, with the rise of global diabetes, a growing number of subjects are suffering from pain and infections caused by the invasive nature of mainstream commercial glucose meters. Non-invasive blood glucose monitoring technology has become an international research topic and a new method which could bring relief to a vast number of patients. This paper reviews the research progress and major challenges of non-invasive blood glucose detection technology in recent years, and divides it into three categories: optics, microwave and electrochemistry, based on the detection principle. The technology covers medical, materials, optics, electromagnetic wave, chemistry, biology, computational science and other related fields. The advantages and limitations of non-invasive and invasive technologies as well as electrochemistry and optics in non-invasives are compared horizontally in this paper. In addition, the current research achievements and limitations of non-invasive electrochemical glucose sensing systems in continuous monitoring, point-of-care and clinical settings are highlighted, so as to discuss the development tendency in future research. With the rapid development of wearable technology and transdermal biosensors, non-invasive blood glucose monitoring will become more efficient, affordable, robust, and more competitive on the market.
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Técnicas Biossensoriais , Automonitorização da Glicemia , Dispositivos Eletrônicos Vestíveis , Glicemia , Humanos , Monitorização FisiológicaRESUMO
Suspension cells can provide a source of cells for cellular reprogramming, but they are difficult to transfect by nonviral vectors. An efficient and safe nonviral vector (GO-Fe3 O4 -PEI complexes) based on iron oxide nanoparticle (Fe3 O4 )-decorated graphene oxide (GO) complexed with polyethylenimine (PEI) for the first time is developed for delivering three individual episomal plasmids (pCXLE-hOCT3/4-shp53, pCXLE-hSK, and pCXLE-hUL) encoding pluripotent-related factors of Oct3/4, shRNA against p53, Sox2, Klf4, L-Myc, and Lin28 into human peripheral blood mononuclear cells (PBMCs) simultaneously. The combined treatment of magnetic stirring and near-infrared (NIR)-laser irradiation, which can promote contact between the complexes and floating cells and increase the cell membrane permeability, respectively, is used to conduct multiple physical stimulations for suspension PBMCs transfection. The PCR analysis shows that the combinatorial effect of magnetic targeting and photothermal stimulation obviously promoted the transfection efficiency of suspension cells. The transfected cells show positive expression of the pluripotency markers, including Nanog, Oct4, and Sox2, and have potential to differentiate into mesoderm and ectoderm cells. The results demonstrate that the GO-Fe3 O4 -PEI complex provides a safe, convenient, and efficient tool for reprogramming PBMCs into partially induced pluripotent stem cells, which are able to rapidly transdifferentiate into mesodermal lineages without full reprogramming.
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Linhagem da Célula , Reprogramação Celular , Grafite/farmacologia , Magnetismo , Mesoderma/citologia , Óxido Ferroso-Férrico/química , Humanos , Fator 4 Semelhante a Kruppel , Polietilenoimina/químicaRESUMO
To investigate the anti-cancer activity of curcumin-loaded hydrogel nanoparticle derived aggregates on A549 lung adenocarcinoma cells. Curcumin was incorporated with biopolymeric chitosan, gelatin, and hyaluronan nanoparticles using an electrostatic field system. Characteristics of curcumin-loaded aggregates were examined including size and morphology, incorporation efficiency, stability and in vitro release. Treatment effect on A549 cells were assessed with cell viability assay, apoptosis assay, cell cycle analysis, reactive oxygen species detection, and Western blot. Observation from transmission electron microscopy show that the prepared biopolymeric nanoparticles were approximately 3-4 nm in diameter and that the size of the aggregates increased to approximately 26-55 nm after the incorporation of curcumin with the nanoparticles. The incorporation efficiency of curcumin into the chitosan, gelatin, and hyaluronan nanoparticles was 81, 67, and 78 % respectively. The formation of hyaluronan/curcumin and gelatin/curcumin aggregates seems to improve the stability of curcumin drug. The chitosan/curcumin aggregate has a faster release of curcumin than gelatin/curcumin and hyaluronan/curcumin aggregates. Treatment with chitosan/curcumin, gelatin/curcumin and hyaluronan/curcumin aggregates resulted in higher apoptosis rates of 45, 40 and 32 %, respectively, as compared to pure curcumin (less than 20 %) via Annexin V-FITC/PI analysis. Chitosan/curcumin aggregates induce the highest apoptosis effect (indicated by sub-G1 phase). In summary, chitosan/curcumin, gelatin/curcumin, and hyaluronan/curcumin aggregates represent higher anticancer proliferation properties in A549 cells than curcumin alone that exhibit great potential enhancement by either using fewer drugs or a decreased duration.
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Antineoplásicos/química , Curcumina/química , Hidrogéis/química , Nanopartículas/química , Apoptose , Materiais Biocompatíveis/química , Ciclo Celular , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Quitosana/química , Ensaios de Seleção de Medicamentos Antitumorais , Citometria de Fluxo , Gelatina/química , Humanos , Ácido Hialurônico/química , Potencial da Membrana Mitocondrial , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Polímeros/química , Espécies Reativas de Oxigênio/químicaRESUMO
BACKGROUND: Low-intensity pulsed ultrasound (LIPUS) regiment has been used to treat fractures with non-union and to promote bone union in general. The effect of LIPUS on articular cartilage metabolism has been characterized. Yet, the effect of LIPUS to repair articular cartilage injury remains unclear in vivo. METHODS: We designed a study to investigate the effect of LIPUS on articular cartilage repairing in a rabbit severe cartilage injury model. Eighteen rabbits were divided into three groups: Sham-operated group, operated group without-LIPUS-treatment, operated group with-LIPUS-treatment (a daily 20-minute treatment for 3 months). Full-thickness cartilage defects were surgically created on the right side distal femoral condyle without intending to penetrate into the subchondral bone, which mimicked severe chondral injury. MR images for experimental joints, morphology grading scale, and histopathological Mankin score were evaluated. RESULTS: The preliminary results showed that the operated groups with-LIPUS-treatment and without-LIPUS-treatment had significantly higher Mankin score and morphological grading scale compared with the sham-operated group. However, there was no significant difference between the with-LIPUS-treatment and without-LIPUS-treatment groups. Cartilage defects filled with proliferative tissue were observed in the with-LIPUS-treatment group grossly and under MR images, however which presented less up-take under Alcian blue stain. Furthermore, no new deposition of type II collagen or proliferation of chondrocyte was observed over the cartilage defect after LIPUS treatment. CONCLUSION: LIPUS has no significant therapeutic potential in treating severe articular cartilage injury in our animal study.
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Doenças das Cartilagens/terapia , Cartilagem Articular , Condrogênese , Regeneração , Terapia por Ultrassom , Animais , Doenças das Cartilagens/patologia , Doenças das Cartilagens/fisiopatologia , Cartilagem Articular/patologia , Cartilagem Articular/fisiopatologia , Modelos Animais de Doenças , Feminino , Imageamento por Ressonância Magnética , Coelhos , Índice de Gravidade de Doença , Fatores de TempoRESUMO
Cartilage tissue engineering involves the invention of novel implantable cartilage replacement materials to help heal cartilage injuries that do not heal themselves, aiming to overcome the shortcomings of current clinical cartilage treatments. Chitosan has been widely used in cartilage tissue engineering because of its similar structure to glycine aminoglycan, which is widely distributed in connective tissues. The molecular weight, as an important structural parameter of chitosan, affects not only the method of chitosan composite scaffold preparation but also the effect on cartilage tissue healing. Thus, this review identifies methods for the preparation of chitosan composite scaffolds with low, medium and high molecular weights, as well as a range of chitosan molecular weights appropriate for cartilage tissue repair, by summarizing the application of different molecular weights of chitosan in cartilage repair in recent years.
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Quitosana , Quitosana/química , Engenharia Tecidual , Peso Molecular , Alicerces Teciduais/química , CartilagemRESUMO
Using a recently established method to prepare hyaluronan/collagen II (HA/Col II) microspheres for a novel biomaterial to couple with living cells/tissues, this animal model study evaluated the effects on a 4-week healing process of chondral defects by the implantation of allogenous chondrocyte-seeded HA/Col II microspheres that had been cultured in vitro for 7 days prior to implantation compared with unseeded HA/Col II microspheres or an untreated wound. Four weeks postsurgery, the untreated group's defect was filled with translucent soft tissue. At the same time, the edges and demarcation lines of the healing defects that were implanted with either HA/Col II microspheres or chondrocyte-seeded HA/Col II microspheres were infused yet recognizable. Furthermore, the new tissues were well integrated into the surrounding articular cartilage. Less glycosaminoglycan (GAG) staining was observed in the defects implanted with HA/Col II microspheres, which indicated that most of the repair tissues were derived from fibrocartilage formation. Conversely, more GAG staining appeared in the defect implanted with chondrocyte-seeded HA/Col II microspheres, which demonstrated a higher level of hyaline cartilage regeneration. Due to the short healing period assigned to this study, the repaired cartilage showed limited incorporation into the surrounding host cartilage and some loose connection to the subchondral bone.
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Materiais Biocompatíveis/uso terapêutico , Cartilagem/cirurgia , Condrócitos/transplante , Colágeno Tipo II/uso terapêutico , Ácido Hialurônico/uso terapêutico , Animais , Cartilagem/lesões , Cartilagem/patologia , Células Cultivadas , Microesferas , Coelhos , Engenharia TecidualRESUMO
Keloid scarring is an abnormal scar disease characterised by excessive proliferation of fibroblasts and over-deposition of collagen during wound healing. Although various treatments for keloid scars have been developed, preventive medicine is believed to be a promising strategy. The skin barrier limits the gentle topical administration of medicaments such as creams and hydrogel dressings, resulting in reduced therapeutic efficacy. In recent years, microneedles (MNs) have been regarded as an appreciable device for topical administration without inducing side effects, and they are painless and do not cause bleeding. In this study, an MN patch with controlled transdermal dual-drug release was developed to achieve combinatory treatment of keloid scars using a heterogeneous gelatin-structured composite MN. Gelatin hydrogel was used as a substrate to load gallic acid (GA) and quercetin-loaded amphiphilic gelatin nanoparticles to fabricate dual-drug heterogeneous composite MNs. The results of the insertion test and mechanical properties of the MNs showed that the heterogeneous composite MN patches could be self-pressed into the stratum corneum and control dual-drug release at different time periods. GA was released at an earlier stage to retard the proliferation of fibroblasts, and quercetin was released at a later stage as a strong antioxidant to erase the generation of reactive oxygen species. Furthermore, real-time quantitative polymerase chain reaction data indicated that the gene expression of fibroblasts (such as Col I and III) was downregulated in the dual-drug system. The above results demonstrate that using heterogeneous composite MNs with the combination of dual-drug pharmacology is beneficial for preventing keloid scar formation.
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Osteoarthritis (OA) is a globally occurring articular cartilage degeneration disease that adversely affects both the physical and mental well-being of the patient, including limited mobility. One major pathological characteristic of OA is primarily related to articular cartilage defects resulting from abrasion and catabolic and proinflammatory mediators in OA joints. Although cell therapy has hitherto been regarded as a promising treatment for OA, the therapeutic effects did not meet expectations due to the outflow of implanted cells. Here, we aimed to explore the repair effect of magnetized chondrocytes using magnetic amphiphilic-gelatin nanocarrier (MAGNC) to enhance cellular anchored efficiency and cellular magnetic guidance (MG) toward the superficial zone of damaged cartilage. The results of in vitro experiments showed that magnetized chondrocytes could be rapidly guided along the magnetic force line to form cellular amassment. Furthermore, the Arg-Gly-Asp (RGD) motif of gelatin in MAGNC could integrate the interaction among cells to form cellular stacking. In addition, MAGNCs upregulated the gene expression of collagen II (Col II), aggrecan, and downregulated that of collagen I (Col I) to reduce cell dedifferentiation. In animal models, the magnetized chondrocytes can be guided into the superficial zone with the interaction between the internal magnetic field and MAGNC to form cellular stacking. In vivo results showed that the intensity of N-sulfated-glycosaminoglycans (sGAG) and Col II in the group of magnetized cells with magnetic guiding was higher than that in the other groups. Furthermore, smooth closure of OA cartilage defects was observed in the superficial zone after 8 weeks of implantation. The study revealed the significant potential of MAGNC in promoting the high-density stacking of chondrocytes into the cartilage surface and retaining the biological functions of implanted chondrocytes for OA cartilage repair.
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Glycated hemoglobin (HbA1c) has been widely explored as an important marker for monitoring and diagnosing diabetes. Due to the advantages of high selectivity, easy preparation, and convenient preservation of aptamers, research on glycated hemoglobin detection utilizing aptasensors has received much attention in recent years. However, factors such as the pH and the salt concentration of the solution and the structure of the aptamer could influence the interactions between HbA1c and the aptamer. In this study, the factors were evaluated using surface plasmon resonance (SPR). The results show that the pH and the salt concentration can greatly affect the formation of a complex between the aptamer and HbA1c. In the stereostructure of the aptamer, loop L1 may be an important motif for recognizing glycated hemoglobin. In addition, the best condition for detecting HbA1c was at pH 6, with a high sensitivity and a low limit of detection(LOD) (1.06 × 10-3RUnM /2.55 nM). The results also demonstrated that the use of an SPR aptamer biosensor can be a sensitive technique to improve the accuracy and correctness of HbA1c measurement.
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Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Hemoglobinas Glicadas/análise , Humanos , Ressonância de Plasmônio de SuperfícieRESUMO
Cell alignment and elongation, which are critical factors correlated with differentiation and maturation in cell biology and tissue engineering, have been widely studied in organisms. Several strategies such as external mechanical strain, geometric topography, micropatterning approaches, and microfabricated substrates have been developed to guide cell alignment, but these methodologies cannot be used for easily denatured natural proteins to modulate the cell behaviour. Herein, for the first time, a novel biocompatible light-controlled protein-based bilayer soft actuator composed of elastin-like polypeptides (ELPs), silk fibroin (SF), graphene oxide (GO), and reduced graphene oxide (rGO), named ESGRG, is developed for efficiently driving cellular orientation and elongation with anisotropic features on soft actuator via remote NIR laser exposure. The actuation of ESGRG could be manipulated by modulating the intensity of NIR and the relative ratio of GO to rGO for promoting myoblasts alignment and nucleus elongation to generate different motions. The results indicate that the YAP and MHC protein expression of C2C12 skeletal muscle cells on ESGRG can be rapidly induced and enhanced by controlling the relative ratio of rGO/GO = 1/4 at a multiple-cycle stimulation with a very low power intensity of 1.2 W cm-2 in friendly liquid environments. This study demonstrates that the ESGRG hydrogel actuator system can modulate the cell-level behaviors via light-driven cyclic bending-motions and can be utilized in applications of soft robotic and tissue engineering such as artificial muscle and maturation of cardiomyocytes.
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Materiais Biocompatíveis/farmacologia , Fibroínas/farmacologia , Grafite/farmacologia , Hidrogéis/farmacologia , Peptídeos/farmacologia , Anisotropia , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Fibroínas/química , Grafite/química , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Raios Infravermelhos , Teste de Materiais , Tamanho da Partícula , Peptídeos/química , Engenharia TecidualRESUMO
Injectable cell-based hydrogels allow surgical operation in a minimally invasive way for articular cartilage lesions but the chondrocytes in the injectable hydrogels are difficultly arrayed and fixed at the site of interest to repair the cartilage tissue. In this study, an injectable hyaluronic acid-polyacrylic acid (HA-pAA) hydrogel was first synthesized using hyaluronic acid-cyclodextrin (HA-CD) and polyacrylic acid-ferrocene (pAA-Fc) to provide cell-delivery and self-healing. To promote the cell fixation and alignment, porous poly(lactic-co-glycolic acid) (PLGA) magnetic microcapsules (PPMMs) with glutathione (GSH) loaded and iron oxide nanoparticles (IO) located in the shell were designed. The GSH-loaded PPMMs with layer-by-layer (LbL) assembly of hyaluronic acid (HA) and GSH (LbL-PPMMs) can provide a two-stage rapid and slow release of GSH to modulate the self-healing of the HA-pAA hydrogel at the injured site. Furthermore, the chondrocytes embedded in the HA-pAA hydrogel could be delivered through CD44 receptors on the HA polymer chains of LbL-PPMMs toward the surface of the damaged site by an internal magnetic force. The composite hydrogel system of chondrocytes/LbL-PPMMs/HA-pAA can provide the damaged cartilage with a more even and smooth surface than other groups in a rabbit model after 8 weeks of implantation. In addition, the chondrocytes in the deep zone tissue exhibit a columnar array, similar to the cell arrangement in normal cartilage tissue. Together with the cell navigation behavior and GSH release from the LbL-PPMM/HA-pAA hydrogel, a full closure of lesions on the cartilage tissue can be achieved. Our results demonstrate the highly promising potential of the injectable LbL-PPMM/HA-pAA system in cartilage tissue repair.
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Cartilagem/lesões , Condrócitos/efeitos dos fármacos , Glutationa/química , Glutationa/farmacocinética , Hidrogéis/química , Fenômenos Magnéticos , Animais , Sobrevivência Celular , Preparações de Ação Retardada , Glutationa/administração & dosagem , Ácido Hialurônico , Nanopartículas Magnéticas de Óxido de Ferro , Masculino , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , CoelhosRESUMO
Although traditional 3D scaffolds or biomimetic hydrogels have been used for tissue engineering and regenerative medicine, soft tissue microenvironment usually has a highly anisotropic structure and a dynamically controllable deformation with various biomolecule distribution. In this study, we developed a hierarchical hybrid gelatin methacrylate-microcapsule hydrogel (HGMH) with Neurotrophin-3(NT-3)-loaded PLGA microcapsules to fabricate anisotropic structure with patterned NT-3 distribution (demonstrated as striped and triangular patterns) by dielectrophoresis (DEP). The HGMH provides a dynamic biomimetic sinuate-microwrinkles change with NT-3 spatial gradient and 2-stage time-dependent distribution, which was further simulated using a 3D finite element model. As demonstrated, in comparison with striped-patterned hydrogel, the triangular-patterned HGMH with highly anisotropic array of microcapsules exhibits remarkably spatial NT-3 gradient distributions that can not only guide neural stem cells (NSCs) migration but also facilitate spinal cord injury regeneration. This approach to construct hierarchical 4D hydrogel system via an electromicrofluidic platform demonstrates the potential for building various biomimetic soft scaffolds in vitro tailed to real soft tissues.
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Hidrogéis , Regeneração da Medula Espinal , Cápsulas , Engenharia Tecidual , Alicerces TeciduaisRESUMO
Current methods for diagnosing early stage osteoarthritis (OA) based on the magnetic resonance imaging and enzyme-linked immunosorbent assay methods are specific, but require specialized laboratory facilities and highly trained personal to obtain a definitive result. In this work, a user friendly and non-invasive quartz crystal microbalance (QCM) immunosensor method has been developed to detect Cartilage Oligomeric Matrix Protein (COMP) for early stage OA diagnosis. This QCM immunosensor was fabricated to immobilize COMP antibodies utilizing the self-assembled monolayer technique. The surface properties of the immunosensor were characterized by its FTIR and electrochemical impedance spectra (EIS). The feasibility study was based on urine samples obtained from 41 volunteers. Experiments were carried out in a flow system and the reproducibility of the electrodes was evaluated by the impedance measured by EIS. Its potential dynamically monitored the immunoreaction processes and could increase the efficiency and sensitivity of COMP detection in laboratory-cultured preparations and clinical samples. The frequency responses of the QCM immunosensor changed from 6 kHz when testing 50 ng/mL COMP concentration. The linear regression equation of frequency shift and COMP concentration was determined as: y=0.0872 x+1.2138 (R2=0.9957). The COMP in urine was also determined by both QCM and EIS for comparison. A highly sensitive, user friendly and cost effective analytical method for the early stage OA diagnosis has thus been successfully developed.
Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Proteínas da Matriz Extracelular/análise , Glicoproteínas/análise , Técnicas de Microbalança de Cristal de Quartzo , Animais , Anticorpos Imobilizados , Anticorpos Monoclonais , Proteína de Matriz Oligomérica de Cartilagem , Estudos de Casos e Controles , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Proteínas da Matriz Extracelular/imunologia , Proteínas da Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/urina , Feminino , Glicoproteínas/imunologia , Glicoproteínas/metabolismo , Glicoproteínas/urina , Humanos , Masculino , Proteínas Matrilinas , Camundongos , Modelos Biológicos , Osteoartrite/diagnóstico , Osteoartrite/metabolismo , Osteoartrite/urina , Técnicas de Microbalança de Cristal de Quartzo/instrumentação , Técnicas de Microbalança de Cristal de Quartzo/métodos , Urinálise/instrumentação , Urinálise/métodosRESUMO
Articular cartilage defect is a common disorder caused by sustained mechanical stress. Owing to its nature of avascular, cartilage had less reconstruction ability so there is always a need for other repair strategies. In this study, we proposed tissue-mimetic pellets composed of chondrocytes and hyaluronic acid-graft-amphiphilic gelatin microcapsules (HA-AGMCs) to serve as biomimetic chondrocyte extracellular matrix (ECM) environments. The multifunctional HA-AGMC with specific targeting on CD44 receptors provides excellent structural stability and demonstrates high cell viability even in the center of pellets after 14 days culture. Furthermore, with superparamagnetic iron oxide nanoparticles (SPIOs) in the microcapsule shell of HA-AGMCs, it not only showed sound cell guiding ability but also induced two physical stimulations of static magnetic field(S) and magnet-derived shear stress (MF) on chondrogenic regeneration. Cartilage tissue-specific gene expressions of Col II and SOX9 were upregulated in the present of HA-AGMC in the early stage, and HA-AGMC+MF+S held the highest chondrogenic commitments throughout the study. Additionally, cartilage tissue-mimetic pellets with magnetic stimulation can stimulate chondrogenesis and sGAG synthesis.
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This study focuses on preparation and valuation of the biodegradable, native, and modified gelatin film as screen-printing substrates. Modified gelatin film was prepared by crosslinking with various crosslinking agents and the electrode array was designed by screen-printing. It was observed that the swelling ratio of C-2, crosslinked with glutaraldehyde and EDC/NHS (1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide) was found to be lower (3.98%) than that of C-1 (crosslinked with only glutaraldehyde) (8.77%) and C-0 (without crosslinking) (28.15%). The obtained results indicate that the swelling ratios of both C-1 and C-2 were found to be lower than that of C-0 (control one without crosslinking). The Young's modulus for C-1 and C-2 was found to be 8.55 ± 0.57 and 23.72 ± 2.04 kPa, respectively. Hence, it was conveyed that the mechanical strength of C-2 was found to be two times higher than that of C-l, suggesting that the mechanical strength was enhanced upon dual crosslinking in this study also. The adhesion study indicates that silver ink adhesion on the gelation surface is better than that of carbon ink. In addition, the electrical response of C-2 with a screen-printed electrode (SPE) was found to be the same as the commercial polycarbonate (PC) substrate. The result of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay suggested that the silver SPE on C-2 was non-cytotoxic toward L929 fibroblast cells proliferation. The results indicated that C-2 gelatin is a promising material to act as a screen-printing substrate with excellent biodegradable and biocompatible properties.
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Platelet gels (PG), activated by bovine thrombin (BT), have increasingly been used in orthopedic surgery. However, BT may induce immunological reactions and carry potential viral and prion risks. To avoid these side effects, thrombin derived from human plasma (human thrombin, HT) is becoming the preferred platelet activator to prepare PG. However, limited experience and data on the clinical benefits of HT-generated PG (HTPG) in orthopedic surgery is reported. Consequently, we designed and performed a series of studies in dogs to compare the impacts of promotion of bone growth by an artificial bone substitute (Osteoset) in combination with HTPG or without it in the spinal repair experiments. X-ray observations and histological studies were performed at predetermined periods post-operation. The preliminary results revealed the preparation of HTPG was easy and required less than 30 minutes. HTPG was capable of embedding the artificial bone substitute Osteoset to prepare a sticky and easily manipulated composite for the application into spinal defect. We found HTPG exhibited enhancement of grafting capacity in consolidation of bone mass. After 12 weeks, tissue reconstruction reached approximately 80% of the injury defects when treated by HTPG/Osteoset combination, but only 30 approximately 40% in the absence of HTPG. The physiological activity of artificial bone substitute combined with PG activated by HT may therefore open beneficial prospects for more successful and safer bone formation in spine procedures in the near future.
Assuntos
Plaquetas/metabolismo , Substitutos Ósseos/administração & dosagem , Osteogênese , Medula Espinal/crescimento & desenvolvimento , Trombina/administração & dosagem , Animais , Substitutos Ósseos/isolamento & purificação , Substitutos Ósseos/metabolismo , Cães , Combinação de Medicamentos , Humanos , Implantes Experimentais , Radiografia , Medula Espinal/diagnóstico por imagem , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Medula Espinal/cirurgia , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/cirurgia , Traumatismos da Medula Espinal/terapia , Trombina/isolamento & purificação , Trombina/metabolismoRESUMO
Due to limited self-healing capacity in cartilages, there is a rising demand for an innovative therapy that promotes chondrocyte proliferation while maintaining its biofunctionality for transplantation. Chondrocyte transplantation has received notable attention; however, the tendencies of cell de-differentiation and de-activation of biofunctionality have been major hurdles in its development, delaying this therapy from reaching the clinic. We believe it is due to the non-stimulative environment in the injured cartilage, which is unable to provide sustainable physical and biological supports to the newly grafted chondrocytes. Therefore, we evaluated whether providing an appropriate matrix to the transplanted chondrocytes could manipulate cell fate and recovery outcomes. Here, we proposed the development of electrosprayed nanoparticles composed of cartilage specific proteins, namely collagen type II and hyaluronic acid, for implantation with pre-seeded chondrocytes into articular cartilage defects. The fabricated nanoparticles were pre-cultured with chondrocytes before implantation into injured articular cartilage. The study revealed a significant potential for nanoparticles to support pre-seeded chondrocytes in cartilage repair, serving as a protein delivery system while improving the survival and biofunctionality of transplanted chondrocytes for prolonged period of time.
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Cartilagem Articular , Condrócitos , Nanopartículas , Alicerces Teciduais , Animais , Materiais Biocompatíveis/química , Colágeno Tipo II/química , Masculino , Nanopartículas/química , Coelhos , Alicerces Teciduais/químicaRESUMO
INTRODUCTION: Stimulating the proliferation and differentiation of chondrocytes for the regeneration of articular cartilage is a promising strategy, but it is currently ineffective. Although both physical stimulation and growth factors play important roles in cartilage repair, their interplay remains unclear and requires further investigation. In this study, we aimed to clarify their contribution using a magnetic drug carrier that not only can deliver growth factors but also provide an external stimulation to cells in the two-dimensional environment. MATERIALS AND METHODS: We developed a nanocapsule (transforming growth factor-ß1 [TGF-ß1]-loaded magnetic amphiphilic gelatin nanocapsules [MAGNCs]; TGF-ß1@MAGNCs) composed of hexanoic-anhydride-grafted gelatin and iron oxide nanoparticles to provide a combination treatment of TGF-ß1 and magnetically induced physical stimuli. With the expression of Arg-Gly-Asp peptide in the gelatin, the TGF-ß1@MAGNCs have an inherent affinity for chondrogenic ATDC5 cells. RESULTS: In the absence of TGF-ß1, ATDC5 cells treated with a magnetic field show significantly upregulated Col2a1 expression. Moreover, TGF-ß1 slowly released from biodegradable TGF-ß1@ MAGNCs further improves the differentiation with increased expression of Col2a1 and Aggrecan. CONCLUSION: Our study shows the time-dependent interplay of physical stimuli and growth factors on chondrogenic regeneration, and demonstrates the promising use of TGF-ß1@MAGNCs for articular cartilage repair.
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Condrócitos/citologia , Condrogênese/efeitos dos fármacos , Nanocápsulas/química , Fator de Crescimento Transformador beta1/farmacocinética , Agrecanas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Condrócitos/efeitos dos fármacos , Condrogênese/fisiologia , Colágeno Tipo II/metabolismo , Gelatina/química , Humanos , Campos Magnéticos , Camundongos , Oligopeptídeos/química , Engenharia Tecidual/métodos , Fator de Crescimento Transformador beta1/genéticaRESUMO
Chitosan was first converted into micro-droplets by using a high voltage electrostatic field system. The droplets were then dropped into a series of Na(5)P(3)O(10)/NaOH solution mixtures with volume ratio of 17:3, 19:1, 1:0 (pure aqueous Na(5)P(3)O(10)) or 0:1 (pure aqueous NaOH) in order to fabricate chitosan microspheres with different membrane structures. The microspheres exhibit distinct chemical and physical properties, including release behaviors of encapsulated drugs. These chitosan microspheres prepared by this method exhibited good sphericity within the range of (286.6 +/- 15.9) to (356 +/- 9.5) microm in diameters. SEM observations have indicated that the chitosan microspheres exhibited distinct surface structures depending on the post-treatment solutions. The mechanical strength of the chitosan microspheres significantly improved upon treatment with Na(5)P(3)O(10)/NaOH solution at ratio of 17:3 (v/v), as compared with the same but at ratio of 19:1, 1:0 (pure Na(5)P(3)O(10)) and 0:1 (pure NaOH) solutions. In addition, chitosan microspheres with unique multi-walled concentric shell membrane structures were prepared by treating with Na(5)P(3)O(10)/NaOH solution at ratio of 19:1. Release studies were carried out to evaluate the kinetic profiles of two model drugs (5-fluorouracil and cytochrome C) from these prepared chitosan microspheres. When chitosan microspheres treated with Na(5)P(3)O(10)/NaOH ratio at 17:3, the release of cytochrome C was found to be the slowest as compared to those treated by the same Na(5)P(3)O(10)/NaOH solution of other mixing ratios, after a period of 35-day "endurance" test. However, in one case, 5-fluorouracil released quite quickly in a period of 30 min (about 80% completion). The wide range of drug release results might be attributed to the unique and wide range of surface characteristics, porosities, and various structures of chitosan microspheres upon treatment with Na(5)P(3)O(10)/NaOH solutions. These results indicate that, by adjusting the Na(5)P(3)O(10)/NaOH ratios, without extra manipulation on polymer material formulation, one could obtain an additional degree of freedom in drug release profile that permits the simultaneous regulation of morphologies of surface texture and internal structure, mechanical properties, and molecular permeability of the microspheres.
Assuntos
Quitosana/química , Quitosana/síntese química , Microesferas , Albuminas , Varredura Diferencial de Calorimetria , Reagentes de Ligações Cruzadas , Citocromos c , Fluoruracila , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Polifosfatos/química , Hidróxido de Sódio/química , Soluções , Espectrofotometria Infravermelho , Resistência à TraçãoRESUMO
Barrier membranes are employed clinically to deflect the growth of gingival tissues away from root surface. They provide an isolated space over the regions with the defective tissues that allow the relatively slow growing periodontal ligament fibroblasts to be repopulated onto the root surface. Several makes of bioabsorbable membranes are now commercially available. In this study, we have employed chitosan as barrier membrane material and evaluated it for a guided tissue regeneration application. Three types of chitosan membranes: Chi-NaOH, Chi-Na(5)P(3)O(10), and Chi-Na(2)SO(3)(each was gelated by NaOH, crosslinked by Na(5)P(3)O(10) and Na(2)SO(3), respectively), were prepared to be evaluated by the following categories: the mechanical strength to create an effective space, the rapid rate to reach hydrolytic equilibrium in phosphate-buffered solution, and the ease of clinical manipulative operations. Consequently, standardized, transosseous and critical sized skull defects were made in adult rats and the defective regions were covered with the specifically prepared chitosan membranes. After 4 weeks of recovering, varying degrees of bone healing were observed beneath the chitosan membranes in comparison to the control group. The chitosan covered regions showed a clear boundary space between connective tissues and bony tissues. Apparently, this process resulted in a good cell occlusion and beneficial osteogenesis effect to the bone. As for the control group, the bone defect was filled with connective tissue, and a destruction of the integrity of newly formed bone was observed. Among the chitosan membranes tested in this study, Chi-NaOH membrane provided a higher percentage of new bone formation than those from the Chi-Na(5)P(3)O(10) and Chi-Na(2)SO(3) families.