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The minimally invasive deployment of scaffolds is a key safety factor for the regeneration of cartilage and bone defects. Osteogenesis relies primarily on cell-matrix interactions, whereas chondrogenesis relies on cell-cell aggregation. Bone matrix expansion requires osteoconductive scaffold degradation. However, chondrogenic cell aggregation is promoted on the repellent scaffold surface, and minimal scaffold degradation supports the avascular nature of cartilage regeneration. Here, a material satisfying these requirements for osteochondral regeneration is developed by integrating osteoconductive hydroxyapatite (HAp) with a chondroconductive shape memory polymer (SMP). The shape memory function-derived fixity and recovery of the scaffold enabled minimally invasive deployment and expansion to fill irregular defects. The crystalline phases on the SMP surface inhibited cell aggregation by suppressing water penetration and subsequent protein adsorption. However, HAp conjugation SMP (H-SMP) enhanced surface roughness and consequent cell-matrix interactions by limiting cell aggregation using crystal peaks. After mouse subcutaneous implantation, hydrolytic H-SMP accelerated scaffold degradation compared to that by the minimal degradation observed for SMP alone for two months. H-SMP and SMP are found to promote osteogenesis and chondrogenesis, respectively, in vitro and in vivo, including the regeneration of rat osteochondral defects using the binary scaffold form, suggesting that this material is promising for osteochondral regeneration.
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Tissue regeneration technology has been rapidly developed and widely applied in tissue engineering and repair. Compared with traditional approaches like surgical treatment, the rising gene therapy is able to have a durable effect on tissue regeneration, such as impaired bone regeneration, articular cartilage repair and cancer-resected tissue repair. Gene therapy can also facilitate the production of in situ therapeutic factors, thus minimizing the diffusion or loss of gene complexes and enabling spatiotemporally controlled release of gene products for tissue regeneration. Among different gene delivery vectors and supportive gene-activated matrices, advanced gene/drug nanocarriers attract exceptional attraction due to their tunable physiochemical properties, as well as excellent adaptive performance in gene therapy for tissue regeneration, such as bone, cartilage, blood vessel, nerve and cancer-resected tissue repair. This paper reviews the recent advances on nonviral-mediated gene delivery systems with an emphasis on the important role of advanced nanocarriers in gene therapy and tissue regeneration.
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Técnicas de Transferência de Genes , Terapia Genética , Regeneração , Engenharia Tecidual , Alicerces Teciduais , Humanos , Animais , Terapia Genética/métodos , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Nanopartículas/química , Portadores de Fármacos/química , Vetores GenéticosRESUMO
Continuous progress has been made in elucidating the relationship between material property, device design, and body function to develop surgical meshes. However, an unmet need still exists wherein the surgical mesh can handle the body motion and thereby promote the repair process. Here, the hernia mesh design and the advanced polymer properties are tailored to synchronize with the anisotropic abdominal motion through shape configuration. The thermomechanical property of shape configurable polymer enables molding of mesh shape to fit onto the abdominal structure upon temperature shift, followed by shape fixing with the release of the heat energy. The microstructural design of mesh is produced through finite element modeling to handle the abdominal motion efficiently through the anisotropic longitudinal and transverse directions. The design effects are validated through in vitro, ex vivo, and in vivo mechanical analyses using a self-configurable, body motion responsive (BMR) mesh. The regenerative function of BMR mesh leads to effective repair in a rat hernioplasty model by effectively handling the anisotropic abdomen motion. Subsequently, the device-tissue integration is promoted by promoting healthy collagen synthesis with fibroblast-to-myofibroblast differentiation. This study suggests a potential solution to promote hernia repair by fine-tuning the relationship between material property and mesh design.
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Hérnia Abdominal , Ratos , Animais , Hérnia Abdominal/cirurgia , Herniorrafia , Teste de Materiais , Telas Cirúrgicas , PolímerosRESUMO
This study investigated the antibacterial properties of Coptis rhizome, a plant traditionally used for respiratory infections, against Streptoccus pneumonia (S. pneumoniae), for which there has been minimal empirical evidence of effectiveness. The study particularly examined autolysis, indirectly associated with antibacterial resistance, when using Coptis rhizome for bacterial infections. In our methodology, Coptis rhizome was processed with ethanol and distilled water to produce four different extracts: CRET30, CRET50, CRET70, and CRDW. The antibacterial activity of these extracts were tested through Minimum Inhibitory Concentration (MIC) assays, disk diffusion tests, and time-kill assays, targeting both standard (ATCC 49619) and resistant (ATCC 70067) strains. The study also evaluated the extracts' biofilm inhibition properties and monitored the expression of the lyt gene, integral to autolysis. The results prominently showed that the CRET70 extract demonstrated remarkable antibacterial strength. It achieved an MIC of 0.125 µg/mL against both tested S. pneumoniae strains. The disk diffusion assay recorded inhibition zones of 22.17 mm for ATCC 49619 and 17.20 mm for ATCC 70067. Impressively, CRET70 resulted in a 2-log decrease in bacterial numbers for both strains, showcasing its potent bactericidal capacity. The extract was also effective in inhibiting 77.40% of biofilm formation. Additionally, the significant overexpression of the lytA gene in the presence of CRET70 pointed to a potential mechanism of action for its antibacterial effects. The outcomes provided new perspectives on the use of Coptis rhizome in combating S. pneumoniae, especially significant in an era of escalating antibiotic resistance.
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Introduction: The study into the interplay between foodborne pathogens and human health, particularly their effects on intestinal cells, is crucial. The importance of lactic acid bacteria (LAB) in promoting a healthy balance of gut microbiota, inhibiting harmful bacteria, and supporting overall gastrointestinal health is becoming more apparent. Methods: Our study delved into the impact of fermenting Woodfordia fruticosa (WF), a plant known for its antimicrobial properties against gastrointestinal pathogens, with LAB. We focused on the influence of this fermentation process on the binding of foodborne pathogens to the gut lining and cytokine production, aiming to enhance gut health and control foodborne infections in HT-29 cells. Results and discussion: Post-fermentation, the WF exhibited improved antimicrobial effects when combined with different LAB strains. Remarkably, the LAB-fermented WF (WFLC) substantially decreased the attachment of pathogens such as L. monocytogenes (6.87% ± 0.33%) and V. parahaemolyticus (6.07% ± 0.50%) in comparison to the unfermented control. Furthermore, WFLC was found to upregulate IL-6 production in the presence of pathogens like E. coli O157:H7 (10.6%) and L. monocytogenes (19%), suggesting it may activate immune responses. Thus, LAB-fermented WF emerges as a potential novel strategy for fighting foodborne pathogens, although additional studies are warranted to thoroughly elucidate WF's phytochemical profile and its contribution to these beneficial outcomes.
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Hepatocellular carcinoma frequently recurs after surgery, necessitating personalized clinical approaches based on tumor avatar models. However, location-dependent oxygen concentrations resulting from the dual hepatic vascular supply drive the inherent heterogeneity of the tumor microenvironment, which presents challenges in developing an avatar model. In this study, tissue samples from 12 patients with hepatocellular carcinoma are cultured directly on a chip and separated based on preference of oxygen concentration. Establishing a dual gradient system with drug perfusion perpendicular to the oxygen gradient enables the simultaneous separation of cells and evaluation of drug responsiveness. The results are further cross-validated by implanting the chips into mice at various oxygen levels using a patient-derived xenograft model. Hepatocellular carcinoma cells exposed to hypoxia exhibit invasive and recurrent characteristics that mirror clinical outcomes. This chip provides valuable insights into treatment prognosis by identifying the dominant hepatocellular carcinoma type in each patient, potentially guiding personalized therapeutic interventions.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Oxigênio , Microambiente Tumoral , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Animais , Camundongos , Oxigênio/metabolismo , Linhagem Celular Tumoral , Masculino , Feminino , Ensaios Antitumorais Modelo de Xenoenxerto , Pessoa de Meia-Idade , Dispositivos Lab-On-A-ChipRESUMO
This research focuses on combating the increasing problem of antimicrobial resistance, especially in Escherichia coli (E. coli), by assessing the efficacy of aminoglycosides. The study specifically addresses the challenge of developing new therapeutic approaches by integrating experimental data with mathematical modeling to better understand the action of aminoglycosides. It involves testing various antibiotics like streptomycin (SMN), kanamycin (KMN), gentamicin (GMN), tobramycin (TMN), and amikacin (AKN) against the O157:H7 strain of E. coli. The study employs a pharmacodynamics (PD) model to analyze how different antibiotic concentrations affect bacterial growth, utilizing minimum inhibitory concentration (MIC) to gauge the effective bactericidal levels of the antibiotics. The study's approach involved transforming bacterial growth rates, as obtained from time-kill curve data, into logarithmic values. A model was then developed to correlate these log-transformed values with their respective responses. To generate additional data points, each value was systematically increased by an increment of 0.1. To simulate real-world variability and randomness in the data, a Gaussian scatter model, characterized by parameters like κ and EC50, was employed. The mathematical modeling was pivotal in uncovering the bactericidal properties of these antibiotics, indicating different PD MIC (zMIC) values for each (SMN: 1.22; KMN: 0.89; GMN: 0.21; TMN: 0.32; AKN: 0.13), which aligned with MIC values obtained through microdilution methods. This innovative blend of experimental and mathematical approaches in the study marks a significant advancement in formulating strategies to combat the growing threat of antimicrobial-resistant E. coli, offering a novel pathway to understand and tackle antimicrobial resistance more effectively.
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Cell chirality is extremely important for the evolution of cell morphogenesis to manipulate cell performance due to left-right asymmetry. Although chiral micro- and nanoscale biomaterials have been developed to regulate cell functions, how cell chirality affects cell nanomechanics to command nuclear mechanotransduction was ambiguous. In this study, chiral engineered microcircle arrays were prepared by photosensitive cross-linking synthesis on cell culture plates to control the clockwise/counterclockwise geometric topology of stem cells. Asymmetric focal adhesion and cytoskeleton structures could induce chiral cell nanomechanics measured by atomic force microscopy (AFM) nanoindentation in left-/right-handed stem cells. Cell nanomechanics could be enhanced when the construction of mature focal adhesion and the assembly of actin and myosin cytoskeletons were well organized in chiral engineered stem cells. Curvature angles had a negative effect on cell nanomechanics, while cell chirality did not change cytoskeletal mechanics. The biased cytoskeleton tension would engender different nuclear mechanotransductions by yes-associated protein (YAP) evaluation. The chiral stimuli were delivered into the nuclei to oversee nuclear behaviors. A strong cell modulus could activate high nuclear DNA synthesis activity by mechanotransduction. The results will bring the possibility of understanding the interplay of chiral cell nanomechanics and mechanotransduction in nanomedicines and biomaterials.
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Mecanotransdução Celular , Células-Tronco Mesenquimais , Mecanotransdução Celular/fisiologia , Citoesqueleto/metabolismo , Células-Tronco , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/metabolismoRESUMO
The structural stability of medical devices is established by managing stress distribution in response to organ movement. Veins abruptly dilate upon arterial grafting due to the mismatched tissue property, resulting in flow disturbances and consequently stenosis. Vascular cast is designed to wrap the vein-artery grafts, thereby adjusting the diameter and property mismatches by relying on the elastic fixity. Here, a small bridge connection in the cast structure serves as an essential element to prevent stress concentrations due to the improved elastic fixity. Consequently, the vein dilation is efficiently suppressed, healthy (laminar and helical) flow is induced effectively, and the heathy functions of vein grafting are promoted, as indicated by the flow directional alignment of endothelial cells with arterialization, muscle expansion, and improved contractility. Finally, collaborative effects of the bridge drastically suppress stenosis with patency improvement. As a key technical point, the advantages of the bridge addition are validated via the computational modeling of fluid-structure interaction, followed by a customized ex vivo set-up and analyses. The calculated effects are verified using a series of cell, rat, and canine models towards translation. The bridge acted like "Little Dutch boy" who saved the big mass using one finger by supporting the cast function.
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Células Endoteliais , Veias , Animais , Cães , Ratos , Constrição Patológica , Hemodinâmica/fisiologiaRESUMO
Tissue regeneration requires structural holding and movement support using tissue-type-specific aids such as bone casts, skin bandages, and joint protectors. Currently, an unmet need exists in aiding breast fat regeneration as the breast moves following continuous body motion by exposing the breast fat to dynamic stresses. Here, the concept of elastic structural holding is applied to develop a shape-fitting moldable membrane for breast fat regeneration ("adipoconductive") after surgical defects are made. The membrane has the following key characteristics: (a) It contains a panel of honeycomb structures, thereby efficiently handling motion stress through the entire membrane; (b) a strut is added into each honeycomb in a direction perpendicular to gravity, thereby suppressing the deformation and stress concentration upon lying and standing; and (c) thermo-responsive moldable elastomers are used to support structural holding by suppressing large deviations of movement that occur sporadically. The elastomer became moldable upon a temperature shift above Tm. The structure can then be fixed as the temperature decreases. As a result, the membrane promotes adipogenesis by activating mechanotransduction in a fat miniature model with pre-adipocyte spheroids under continuous shaking in vitro and in a subcutaneous implant placed on the motion-prone back areas of rodents in vivo.
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Interconnected pore structures of scaffolds are important to control the cell functions for cartilage tissue engineering. In this study, collagen scaffolds with interconnected pore structures were prepared using poly(D,L-lactide-co-glycolide) (PLGA) sponges as sacrificial templates. Six types of PLGA sponges of different pore sizes and porosities were prepared by the solvent casting/particulate leaching method and used to regulate the interconnectivity of the collagen scaffolds. The integral and continuous templating structure of PLGA sponges generated well-interconnected pore structures in the collagen scaffolds. Bovine articular chondrocytes cultured in collagen scaffolds showed homogenous distribution, fast proliferation, high expression of cartilaginous genes and high secretion of cartilaginous extracellular matrix. In particular, the collagen scaffold templated by the PLGA sacrificial sponge that was prepared with a high weight ratio of PLGA and large salt particulates showed the most promotive effect on cartilage tissue formation. The interconnected pore structure facilitated cell distribution, cell-cell interaction and cartilage tissue regeneration.
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Cartilagem/fisiologia , Colágeno/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Materiais Biocompatíveis , Bovinos , Adesão Celular , Sobrevivência Celular , Condrócitos/fisiologiaRESUMO
Extracellular matrices (ECMs) are dynamically altered and remodeled during tissue development. How the dynamic remodeling of ECM affects stem cell functions remains poorly understood due to the difficulty of obtaining biomimetic ECMs. In this study, stepwise osteogenesis-mimicking ECM-deposited hybrid meshes were prepared by culturing human mesenchymal stem cells (hMSCs) in poly (lactic-co-glycolic acid) (PLGA)-collagen hybrid meshes and controlling the stages of the osteogenesis of hMSCs. Three types of hybrid mesh mimicking the ECMs that were secreted from stem cell stage of hMSCs (SC-ECM), early stage (EO-ECM) and late stage (LO-ECM) osteogenesis of hMSCs were prepared. The stepwise osteogenesis-mimicking ECM deposited PLGA-collagen hybrid meshes showed different ECM compositions associated with the stage of osteogenesis. Their effects on the osteogenic differentiation of hMSCs differed. EO-ECM scaffold increased and LO-ECM scaffold moderately promoted the osteogenic differentiation of hMSCs. However, SC-ECM scaffold inhibited the osteogenic differentiation of hMSCs. The novel PLGA-collagen-ECM hybrid meshes will provide useful tools for stem cell culture and tissue engineering.
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Técnicas de Cultura de Células/métodos , Diferenciação Celular , Colágeno/química , Matriz Extracelular/química , Osteogênese , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Engenharia TecidualRESUMO
Endochondral ossification (ECO) is an important process of bone tissue development. During ECO, extracellular matrices (ECMs) are essential factors to control cell functions and induce bone regeneration. However, the exact role of ECO ECMs on stem cell differentiation remains elusive. In this study, ECM scaffolds were prepared to mimic the ECO-related ECM microenvironments and their effects on stem cell differentiation were compared. Four types of ECM scaffolds mimicking the ECMs of stem cells (SC), chondrogenic (CH), hypertrophic (HY) and osteogenic (OS) stages were prepared by controlling differentiation of human bone marrow-derived mesenchymal stem cells (MSCs) at different stages. Composition of the ECM scaffolds was dependent on the differentiation stage of MSCs. They showed different influence on osteogenic differentiation of MSCs. HY ECM scaffold had the most promotive effect on osteogenic differentiation of MSCs. CH ECM and OS ECM scaffolds showed moderate effect, while SC ECM scaffold had the lowest effect on osteogenic differentiation of MSCs. Their effects on chondrogenic or adipogenic differentiation were not significantly different. The results suggested that the engineered HY ECM scaffold had superior effect for osteogenic differentiation of MSCs. Statement of significance ECM scaffolds mimicking endochondral ossification-related ECM microenvironments are pivotal for elucidation of their roles in regulation of stem cell functions and bone tissue regeneration. This study offers a method to prepare ECM scaffolds that mimic the ECMs from cells at hypertrophic, osteogenic, chondrogenic and stem cell stages. Their composition and impacts on osteogenic differentiation of MSCs were compared. The hypertrophic ECM scaffold had the highest promotive effect on osteogenic differentiation of MSCs. The results advance our understanding about the role of ECO ECMs in regulation of stem cell functions and provide perspective for bone defect repair strategies.
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Células-Tronco Mesenquimais , Osteogênese , Diferenciação Celular , Condrogênese , Matriz Extracelular , Humanos , Alicerces TeciduaisRESUMO
Accumulating evidence indicates that stem cell fate can be regulated by mechanical properties of the extracellular matrix. Most studies have focused onthe influence of matrix elasticity and viscoelasticity on stem cell differentiation. However, how matrix viscosity affects stem cell differentiation has been overlooked. In this study, a biphasic gelatin solution/hydrogel system is used for 3D culture of human bone marrow-derived mesenchymal stem cells (MSCs) to investigate the influence of gelatin solution viscosity on simultaneous osteogenic and adipogenic differentiation at the same culture condition. Gelatin solution promotes cell proliferation, while its promotive effect decreases with the increase of viscosity. The influence of viscosity on osteogenic and adipogenic differentiation of MSCs shows opposite trends. A high-viscosity gelatin solution results in an increase of alkaline phosphatase (ALP) activity, calcium deposition, and expression of osteogenesis-related genes. On the other hand, in a low-viscosity gelatin solution, a lot of lipid vacuoles are formed and adipogenesis-related genes are highly expressed. The results indicate high viscosity is beneficial for osteogenic differentiation, while low viscosity is beneficial for adipogenic differentiation. These findings suggest the importance of matrix viscosity on stem cell differentiation in 3D microenvironments.
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A shift in osteogenesis toward adipogenesis of human bone marrow-derived mesenchymal stem cells (hMSCs) is a crucial pathological factor in the progression of osteoporosis. The development of an in vitro three-dimensional (3D) model that reflects the dynamic remodeling of extracellular matrices (ECMs) during simultaneous osteogenesis and adipogenesis of hMSCs can provide a useful tool to mimic the process and to investigate how 3D ECMs balance the osteogenic and adipogenic differentiation of hMSCs. In this study, ECMs secreted by hMSCs during their stepwise osteogenesis-co-adipogenesis were deposited on hybrid meshes of poly(lactide-co-glycolide) (PLGA) and collagen to prepare biomimetic PLGA-collagen-ECM hybrid scaffolds. Four types of stepwise differentiation ECMs were prepared: ECMs secreted by hMSCs at early stages of osteogenesis and adipogenesis (EOEA-ECMs), hMSCs at early stages of osteogenesis and late stages of adipogenesis (EOLA-ECMs), hMSCs at late stages of osteogenesis and early stages of adipogenesis (LOEA-ECMs) and hMSCs at late stages of osteogenesis and late stages of adipogenesis (LOLA-ECMs). The deposited ECMs had different compositions that were dependent on the different stages of osteogenesis and adipogenesis. They also showed different effects on balancing the adipogenic and osteogenic differentiation of hMSCs. The EOEA-ECM scaffold had a promotive effect on adipogenesis and a suppressive effect on the osteogenesis of hMSCs. The LOEA-ECM and LOLA-ECM scaffolds showed a promotive effect on osteogenesis and a moderate effect on the adipogenic differentiation of hMSCs. The EOLA-ECM scaffold exhibited a suppressive effect on both osteogenesis and adipogenesis of hMSCs. However, the EOLA-ECM scaffold promoted hMSC proliferation more strongly than the other ECM scaffolds. The results indicated that dynamically remodeling ECM scaffolds could affect the osteogenic and adipogenic differentiation of hMSCs and should provide a useful 3D cell culture model for the investigation of ECM-cell interactions.
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Materiais Biomiméticos/química , Colágeno/química , Matriz Extracelular/química , Células-Tronco Mesenquimais/química , Poliglactina 910/química , Adipogenia , Técnicas de Cultura de Células , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia , Osteogênese , Tamanho da Partícula , Propriedades de Superfície , Alicerces TeciduaisRESUMO
Cells are surrounded by an extracellular matrix (ECM), which controls cellular functions through biological or physicochemical cues. In particular, cartilage tissues have abundant ECM that is viscoelastic and provides the necessary signals for the maintenance of chondrocyte activity and metabolism. The influence of ECM stiffness on chondrocyte functions has been broadly investigated using elastic hydrogels. However, it is not clear how viscosity impacts chondrocyte functions. In this study, a biphasic gelatin solution/hydrogel system was established for the three-dimensional culture of bovine articular chondrocytes (BACs) to investigate the influence of gelatin solution viscosity on chondrocyte proliferation, ECM secretion and the maintenance of the chondrocyte phenotype. Gelatin solutions of different viscosities supported chondrocyte proliferation and ECM production. However, the cell morphology, proliferation rate, secreted ECM quantity and gene expression levels were different, and these were dependent on the viscosity of the gelatin solutions. Low-viscosity solutions were more beneficial for proliferation, while high-viscosity solutions were more beneficial for ECM production and the expression of collagen type II and aggrecan. Chondrocytes had a more spread morphology in a low-viscosity gelatin solution than in a high-viscosity gelatin solution. The results suggested that high-viscosity was more beneficial for the maintenance of the chondrocyte phenotype, while low viscosity was more beneficial for cell expansion. Viscosity was demonstrated as one of the key parameters affecting cell morphology, proliferation and phenotype.
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Técnicas de Cultura de Células/métodos , Proliferação de Células , Condrócitos/citologia , Meios de Cultura/química , Fenótipo , Animais , Bovinos , Matriz Extracelular/metabolismo , Gelatina/química , ViscosidadeRESUMO
Extracellular matrixes (ECMs) play a vital role in controlling cell functions because of their similarity to the in vivo microenvironment. The composition of ECMs is not constant but dynamically remolded during stem cell differentiation and tissue development. Development of three-dimensional (3D) biomimetic ECM scaffolds is desirable for investigation of ECM-cell interactions and tissue engineering applications. Here, 3D ECM scaffolds that mimicked the dynamic ECM remodeling during stepwise adipogenesis of human mesenchymal stem cells (hMSCs) were developed. A biodegradable hybrid mesh of poly-(dl-lactic-co-glycolic acid) and collagen was used as a template for cell culture. hMSCs were cultured in the hybrid mesh, and their adipogenic differentiation was controlled at early, late, and undifferentiated stages. Three types of stepwise 3D ECM hybrid scaffolds were prepared from the cultured cells after decellularization. They are mesenchymal stem cell ECM scaffold (SC-ECM scaffold), early-stage adipogenesis-mimicking ECM scaffold (EA-ECM scaffold), and late-stage adipogenesis-mimicking ECM scaffold (LA-ECM scaffold). The stepwise 3D ECM scaffolds had a different composition that was dependent on the differentiation stage of hMSCs. They also showed a different influence on the adipogenic differentiation of hMSCs. The EA-ECM scaffold promoted, while the SC-ECM and LA-ECM scaffolds inhibited the adipogenic differentiation of hMSCs.
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Fendas de Ciclodiálise , Traumatismos Oculares , Hipotensão Ocular , Humanos , Hipotensão Ocular/etiologia , Hipotensão Ocular/diagnóstico , Hipotensão Ocular/fisiopatologia , Traumatismos Oculares/diagnóstico , Traumatismos Oculares/complicações , Traumatismos Oculares/etiologia , Masculino , Fendas de Ciclodiálise/diagnóstico , Fendas de Ciclodiálise/etiologia , Fendas de Ciclodiálise/cirurgia , Pressão Intraocular/fisiologia , Doenças Retinianas/etiologia , Doenças Retinianas/diagnóstico , Ferimentos não Penetrantes/diagnóstico , Ferimentos não Penetrantes/complicações , Tomografia de Coerência Óptica , Cápsula do Cristalino/lesões , Cápsula do Cristalino/cirurgia , Acuidade VisualRESUMO
The orientational variation of 4-cyano-4'-pentyl biphenyl (5CB) molecules in LC microdroplets in response to IgG antigen (IgG) interactions has been utilized to develop a biosensor for rapid and label-free detection of IgG in biological fluids. In order to prepare a LC microdroplet-based biosensor, the anti-IgG (AIgG) anchored 4-cyano-4'-pentyl biphenyl LC microdroplets were prepared in the presence of sodium dodecylsulfate (SDS) as a mediator and amphiphilic poly(styrene-b-acrylic acid) (PS-b-PA) as a modifier of the LC/water interface. The AIgG-anchored LC microdroplets with a size variation from 20 to 30 µm have been used successfully for the detection of IgG within a concentration range of 20 to 1000 ng mL-1, at a detection limit of as low as 16 ng mL-1, and a response time of 30 min in PBS solution at room temperature. The LC microdroplets anchored with 5 µg mL-1 of AIgG were found to be more sensitive for the detection of IgG in the concentration range from 20 to 800 ng mL-1 in PBS. The AIgG-anchored LC microdroplets have shown a delayed response of 90 minutes for IgG in a solution containing 10% FBS or 10% blood plasma in comparison to PBS solution. The LC microdroplets anchored with 5 µg mL-1 (34 pmol) of AIgG have shown a recovery of 106% of IgG, a coefficient of variance of ±4% and a precision within a limit of 1-6% for a spiked sample of 25 ng mL-1 of IgG. The results indicated that orientational response of LC microdroplets is potentially useful to develop a biosensor for in vivo detection of proteins or pathogens in a biological fluid.