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1.
Phys Chem Chem Phys ; 26(18): 13850-13861, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38656824

RESUMEN

Isocyanates play an essential role in modern manufacturing processes, especially in polyurethane production. There are numerous synthesis strategies for isocyanates both under industrial and laboratory conditions, which do not prevent searching for alternative highly efficient synthetic protocols. Here, we report a detailed theoretical investigation of the mechanism of sulfur dioxide-catalyzed rearrangement of phenylnitrile oxide into phenyl isocyanate, which was first reported in 1977. The DLPNO-CCSD(T) method and up-to-date DFT protocols were used to perform a highly accurate quantum-chemical study of the rearrangement mechanism. An overview of various organic and inorganic catalysts has revealed other potential catalysts, such as sulfur trioxide and selenium dioxide. Furthermore, the present study elucidated how substituents in phenylnitrile oxide influence reaction kinetics. This study was performed by a self-organized collaboration of scientists initiated by a humorous post on the VK social network.

2.
Cell Tissue Res ; 390(3): 453-464, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36129531

RESUMEN

In situ 3D bioprinting is a new emerging therapeutic modality for treating human skin diseases. The tissue spheroids have been previously suggested as a powerful tool in rapidly expanding bioprinting technology. It has been demonstrated that the regenerative potential of human dermal fibroblasts could be quantitatively evaluated in 2D cell culture and confirmed after implantation in vivo. However, the development of unbiassed quantitative criteria of the regenerative potential of 3D tissue spheroids in vitro before their in situ bioprinting remains to be investigated. Here it has been demonstrated for the first time that specific correlations exist between the regenerative potential of human dermal fibroblasts cultured in vitro as 2D cell monolayer with biological properties of 3D tissue spheroids fabricated from these fibroblasts. In vitro assessment of biological properties included diameter, spreading and fusion kinetics, and biomechanical properties of 3D tissue spheroids. This comprehensive characterization could be used to predict tissue spheroids' regenerative potential in vivo.


Asunto(s)
Bioimpresión , Esferoides Celulares , Humanos , Fibroblastos , Técnicas de Cultivo de Célula , Piel , Ingeniería de Tejidos
3.
Int J Mol Sci ; 23(3)2022 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35163759

RESUMEN

Changes in bacterial physiology caused by the combined action of the magnetic force and microgravity were studied in Escherichia coli grown using a specially developed device aboard the International Space Station. The morphology and metabolism of E. coli grown under spaceflight (SF) or combined spaceflight and magnetic force (SF + MF) conditions were compared with ground cultivated bacteria grown under standard (control) or magnetic force (MF) conditions. SF, SF + MF, and MF conditions provided the up-regulation of Ag43 auto-transporter and cell auto-aggregation. The magnetic force caused visible clustering of non-sedimenting bacteria that formed matrix-containing aggregates under SF + MF and MF conditions. Cell auto-aggregation was accompanied by up-regulation of glyoxylate shunt enzymes and Vitamin B12 transporter BtuB. Under SF and SF + MF but not MF conditions nutrition and oxygen limitations were manifested by the down-regulation of glycolysis and TCA enzymes and the up-regulation of methylglyoxal bypass. Bacteria grown under combined SF + MF conditions demonstrated superior up-regulation of enzymes of the methylglyoxal bypass and down-regulation of glycolysis and TCA enzymes compared to SF conditions, suggesting that the magnetic force strengthened the effects of microgravity on the bacterial metabolism. This strengthening appeared to be due to magnetic force-dependent bacterial clustering within a small volume that reinforced the effects of the microgravity-driven absence of convectional flows.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/genética , Técnicas Bacteriológicas/instrumentación , Proteínas de Escherichia coli/genética , Escherichia coli/fisiología , Proteínas de Transporte de Membrana/genética , Técnicas Bacteriológicas/métodos , Escherichia coli/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica , Glucólisis , Glioxilatos/metabolismo , Fenómenos Magnéticos , Oxígeno/metabolismo , Piruvaldehído/metabolismo , Vuelo Espacial , Ingravidez
4.
J Mater Sci Mater Med ; 30(3): 31, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30830351

RESUMEN

Collagen is one of the most promising materials for 3D bioprinting because of its distinguished biocompatibility. Cell-laden constructs made of pure collagen with or without incorporated growth supplements support engineered constructs persistence in culture and are perfectly suitable for grafting. The limiting factor for direct 3D collagen printing was poor printability of collagen solutions, especially admixed with cells or tissue spheroids. In our study, we showed that concentrated solutions of native collagen branded Viscoll were effective as bioinks with high fidelity performance. Viscoll containing 20, 30, or 40 mg/ml collagen were used for direct extrusion 3D bioprinting to form scaffolds appropriate to support spatial arrangement of tissue spheroids into rigid patterns with resolution of 0.5 mm in details. Incorporated cells demonstrated sufficient viability. Associated rheological study showed that good printability of the collagen solutions correlates with their increased storage modulus value, notably exceeding the loss modulus value. The proper combination of these physical parameters could become technological criteria for manufacturing various collagen bioinks for 3D bioprinting.


Asunto(s)
Materiales Biocompatibles/química , Bioimpresión/métodos , Colágeno/química , Impresión Tridimensional , Animales , Supervivencia Celular , Descubrimiento de Drogas , Humanos , Hidrogeles/química , Ensayo de Materiales , Ratones , Células 3T3 NIH , Presión , Medicina Regenerativa , Reología , Esferoides Celulares , Estrés Mecánico , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
5.
Proteins ; 83(11): 2091-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26370130

RESUMEN

Interpretation of the experiments showing that the Ras-GAP protein complex maintains activity in guanosine triphosphate (GTP) hydrolysis upon replacement of Glu61 in Ras with its unnatural nitro analog, NGln, is an important issue for understanding details of chemical transformations at the enzyme active site. By using molecular modeling we demonstrate that both glutamine and its nitro analog in the aci-nitro form participate in the reaction of GTP hydrolysis at the stages of proton transfer and formation of inorganic phosphate. The computed structures and the energy profiles for the complete pathway from the enzyme-substrate to enzyme-product complexes for the wild-type and mutated Ras suggest that the reaction mechanism is not affected by this mutation.


Asunto(s)
Ácido Glutámico/química , Glutamina/química , Proteínas ras/química , Proteínas ras/genética , Guanosina Trifosfato/química , Guanosina Trifosfato/metabolismo , Hidrólisis , Mutación
6.
Proteins ; 83(6): 1046-53, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25820867

RESUMEN

The free energy profiles for the chemical reaction of the guanosine triphosphate hydrolysis GTP + H2O → GDP + Pi by Ras-GAP for the wild-type and G13V mutated Ras were computed by using molecular dynamics protocols with the QM(ab initio)/MM potentials. The results are consistent with the recent measurements of reaction kinetics in Ras-GAP showing about two-order reduction of the rate constant upon G13V mutation in Ras: the computed activation barrier on the free energy profile is increased by 3 kcal/mol upon the G13V replacement. The major reason for a higher energy barrier is a shift of the "arginine finger" (R789 from GAP) from the favorable position in the active site. The results of simulations provide support for the mechanism of the reference reaction according to which the Q61 side chain directly participates in chemical transformations at the proton transfer stage.


Asunto(s)
Guanosina Trifosfato/metabolismo , Proteínas Activadoras de ras GTPasa/metabolismo , Proteínas ras/metabolismo , Biología Computacional , Guanosina Trifosfato/química , Hidrólisis , Modelos Moleculares , Mutación/genética , Mutación/fisiología , Conformación Proteica , Termodinámica , Proteínas Activadoras de ras GTPasa/química , Proteínas Activadoras de ras GTPasa/genética , Proteínas ras/química
7.
Biochemistry ; 53(45): 7093-9, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25339142

RESUMEN

Cancer-associated point mutations in Ras, in particular, at glycine 12 and glycine 13, affect the normal cycle between inactive GDP-bound and active GTP-bound states. In this work, the role of G12V and G13V replacements in the GAP-stimulated intrinsic GTP hydrolysis reaction in Ras is studied using molecular dynamics (MD) simulations with quantum mechanics/molecular mechanics (QM/MM) potentials. A model molecular system was constructed by motifs of the relevant crystal structure (Protein Data Bank entry 1WQ1 ). QM/MM optimization of geometry parameters in the Ras-GAP-GTP complex and QM/MM-MD simulations were performed with a quantum subsystem comprising a large fraction of the enzyme active site. For the system with wild-type Ras, the conformations fluctuated near the structure ready to be involved in the efficient chemical reaction leading to the cleavage of the phosphorus-oxygen bond in GTP upon approach of the properly aligned catalytic water molecule. Dynamics of the system with the G13V mutant is characterized by an enhanced flexibility in the area occupied by the γ-phosphate group of GTP, catalytic water, and the side chains of Arg789 and Gln61, which should somewhat hinder fast chemical steps. Conformational dynamics of the system with the G12V mutant shows considerable displacement of the Gln61 side chain and catalytic water from their favorable arrangement in the active site that may lead to a marked reduction in the reaction rate. The obtained computational results correlate well with the recent kinetic measurements of the Ras-GAP-catalyzed hydrolysis of GTP.


Asunto(s)
Subunidades alfa de la Proteína de Unión al GTP G12-G13/fisiología , Guanosina Trifosfato/metabolismo , Modelos Moleculares , Mutación/fisiología , Proteínas Activadoras de ras GTPasa/metabolismo , Secuencia de Aminoácidos , Catálisis , Subunidades alfa de la Proteína de Unión al GTP G12-G13/química , Guanosina Trifosfato/química , Guanosina Trifosfato/genética , Hidrólisis , Datos de Secuencia Molecular , Proteínas Activadoras de ras GTPasa/química , Proteínas Activadoras de ras GTPasa/genética
8.
Cells ; 12(4)2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36831277

RESUMEN

Organoids are microtissues that recapitulate the complex structural organization and functions of tissues and organs. Nanoparticles have several specific properties that must be considered when replacing animal models with in vitro studies, such as the formation of a protein corona, accumulation, ability to overcome tissue barriers, and different severities of toxic effects in different cell types. An increase in the number of articles on toxicology research using organoid models is related to an increase in publications on organoids in general but is not related to toxicology-based publications. We demonstrate how the quantitative assessment of toxic changes in the structure of organoids and the state of their cell collections provide more valuable results for toxicological research and provide examples of research methods. The impact of the tested materials on organoids and their differences are also discussed. In conclusion, we highlight the main challenges, the solution of which will allow researchers to approach the replacement of in vivo research with in vitro research: biobanking and standardization of the structural characterization of organoids, and the development of effective screening imaging techniques for 3D organoid cell organization.


Asunto(s)
Bancos de Muestras Biológicas , Nanopartículas , Animales , Organoides , Modelos Animales
9.
Int J Bioprint ; 9(2): 675, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37065657

RESUMEN

In situ bioprinting is one of the most clinically relevant techniques in the emerging bioprinting technology because it could be performed directly on the human body in the operating room and it does not require bioreactors for post-printing tissue maturation. However, commercial in situ bioprinters are still not available on the market. In this study, we demonstrated the benefit of the originally developed first commercial articulated collaborative in situ bioprinter for the treatment of full-thickness wounds in rat and porcine models. We used an articulated and collaborative robotic arm from company KUKA and developed original printhead and correspondence software enabling in situ bioprinting on curve and moving surfaces. The results of in vitro and in vivo experiments show that in situ bioprinting of bioink induces a strong hydrogel adhesion and enables printing on curved surfaces of wet tissues with a high level of fidelity. The in situ bioprinter was convenient to use in the operating room. Additional in vitro experiments (in vitro collagen contraction assay and in vitro 3D angiogenesis assay) and histological analyses demonstrated that in situ bioprinting improves the quality of wound healing in rat and porcine skin wounds. The absence of interference with the normal process of wound healing and even certain improvement in the dynamics of this process strongly suggests that in situ bioprinting could be used as a novel therapeutic modality in wound healing.

10.
Mol Ther Nucleic Acids ; 32: 267-288, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37090419

RESUMEN

Here, we present DNA aptamers capable of specific binding to glial tumor cells in vitro, ex vivo, and in vivo for visualization diagnostics of central nervous system tumors. We selected the aptamers binding specifically to the postoperative human glial primary tumors and not to the healthy brain cells and meningioma, using a modified process of systematic evolution of ligands by exponential enrichment to cells; sequenced and analyzed ssDNA pools using bioinformatic tools and identified the best aptamers by their binding abilities; determined three-dimensional structures of lead aptamers (Gli-55 and Gli-233) with small-angle X-ray scattering and molecular modeling; isolated and identified molecular target proteins of the aptamers by mass spectrometry; the potential binding sites of Gli-233 to the target protein and the role of post-translational modifications were verified by molecular dynamics simulations. The anti-glioma aptamers Gli-233 and Gli-55 were used to detect circulating tumor cells in liquid biopsies. These aptamers were used for in situ, ex vivo tissue staining, histopathological analyses, and fluorescence-guided tumor and PET/CT tumor visualization in mice with xenotransplanted human astrocytoma. The aptamers did not show in vivo toxicity in the preclinical animal study. This study demonstrates the potential applications of aptamers for precise diagnostics and fluorescence-guided surgery of brain tumors.

11.
Polymers (Basel) ; 14(23)2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36501463

RESUMEN

The concept of "lockyballs" or interlockable mini-scaffolds fabricated by two-photon polymerization from biodegradable polymers for the encagement of tissue spheroids and their delivery into the desired location in the human body has been recently introduced. In order to improve control of delivery, positioning, and assembly of mini-scaffolds with tissue spheroids inside, they must be functionalized. This review describes the design, fabrication, and functionalization of mini-scaffolds as well as perspectives on their application in tissue engineering for precisely controlled cell and mini-tissue delivery and patterning. The development of functionalized mini-scaffolds advances the original concept of "lockyballs" and opens exciting new prospectives for mini-scaffolds' applications in tissue engineering and regenerative medicine and their eventual clinical translation.

12.
Photodiagnosis Photodyn Ther ; 40: 103202, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36400167

RESUMEN

Efficient screening of photosensitizers (PS) as well as studying their photodynamic activity, especially PS excited in the near-infrared region, require informative in vitro models to adequately reflect the architecture, thickness, and intercellular interactions in tumors. In our study, we used spheroids formed from human colon cancer HCT-116 cells and liver cancer Huh7 cells to assess the phototoxicity of a new PS based on tetracationic derivative of synthetic bacteriochlorin (BC4). We optimized conditions for the irradiation regime based on the kinetics of BC4 accumulation in spheroids and kinetics of spheroid growth. Although PS accumulated more efficiently in HCT-116 cells, characterized by more aggressive growth and high proliferative potential, they were less susceptible to the photodynamic therapy (PDT) compared to the slower growing Huh7 cells. We also showed that 3D models of spheroids were less sensitive to BC4 than conventional 2D cultures with relatively identical kinetics of drug accumulation. Our findings suggest that BC4 is a perspective agent for photodynamic therapy against cancer cells.


Asunto(s)
Neoplasias del Colon , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Neoplasias del Colon/tratamiento farmacológico , Células HCT116 , Línea Celular Tumoral , Hígado
13.
Toxicology ; 462: 152952, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34543703

RESUMEN

Nanotoxicological studies using existing models of normal cells and animals often encounter a paradox: retention of nanoparticles in intracellular compartments for a long time is not accompanied by any significant toxicological effects. Can we expect that the revealed changes will be not harmful after translation to practice, outside of a sterile laboratory and ideally healthy organisms? Age-associated and pathological processes can affect target organs, metabolism, and detoxification in the mononuclear phagocyte system organs and change biodistribution routes, thus making the use of nanomaterial not safe. The potential solution to this issue can be testing the toxic properties of nanoparticles in animal models with chronic diseases. However, current studies of nanotoxicity in animal models with a brain, cardiovascular system, liver, digestive tract, reproductive system, and skin diseases are unsystematic. Even though these studies demonstrate the emergence of new toxic effects that are not present in healthy animals. In this regard, we set the goal of this review as the formulation of the requirements for an animal model capable of assessing the potential toxicity of nanoparticles based on the nanosafety approach.


Asunto(s)
Modelos Animales de Enfermedad , Nanopartículas/toxicidad , Pruebas de Toxicidad/métodos , Animales , Humanos , Modelos Animales , Distribución Tisular , Toxicología/métodos
14.
Nanotoxicology ; 15(2): 167-204, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33216662

RESUMEN

The unique properties of magnetic iron oxide nanoparticles determined their widespread use in medical applications, the food industry, textile industry, which in turn led to environmental pollution. These factors determine the long-term nature of the effect of iron oxide nanoparticles on the body. However, studies in the field of chronic nanotoxicology of magnetic iron particles are insufficient and scattered. Studies show that toxicity may be increased depending on oral and inhalation routes of administration rather than injection. The sensory nerve pathway can produce a number of specific effects not seen with other routes of administration. Organ systems showing potential toxic effects when injected with iron oxide nanoparticles include the nervous system, heart and lungs, the thyroid gland, and organs of the mononuclear phagocytic system (MPS). A special place is occupied by the reproductive system and the effect of nanoparticles on the health of the first and second generations of individuals exposed to the toxic effects of iron oxide nanoparticles. This knowledge should be taken into account for subsequent studies of the toxicity of iron oxide nanoparticles. Particular attention should be paid to tests conducted on animals with pathologies representing human chronic socially significant diseases. This part of preclinical studies is almost in its infancy but of great importance for further medical translation on nanomaterials to practice.


Asunto(s)
Compuestos Férricos/toxicidad , Fenómenos Magnéticos , Nanopartículas/toxicidad , Animales , Ingeniería Biomédica , Células Cultivadas , Compuestos Férricos/química , Humanos , Nanopartículas/química , Especificidad de Órganos , Estrés Oxidativo/efectos de los fármacos , Tamaño de la Partícula , Propiedades de Superficie , Pruebas de Toxicidad , Transcriptoma/efectos de los fármacos
15.
ACS Biomater Sci Eng ; 7(11): 5206-5214, 2021 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-34610738

RESUMEN

Magnetic tissue engineering is one of the rapidly emerging and promising directions of tissue engineering and biofabrication where the magnetic field is employed as temporal removal support or scaffold. Iron oxide nanoparticles are used to label living cells and provide the desired magnetic properties. Recently, polymer microcapsules loaded with iron oxide nanoparticles have been proposed as a novel approach to designing magnetic materials with high local concentrations. These microcapsules can be readily internalized and retained intracellularly for a long time in various types of cells. The low cytotoxicity of these microcapsules was previously shown in 2D cell culture. This paper has demonstrated that cells containing these nontoxic nanomaterials can form viable 3D tissue spheroids for the first time. The spheroids retained labeled fluorescent microcapsules with magnetic nanoparticles without a detectable cytotoxic effect. The high concentration of packed nanoparticles inside the microcapsules enables the evident magnetic properties of the labeled spheroids to be maintained. Finally, magnetic spheroids can be effectively used for magnetic patterning and biofabrication of tissue-engineering constructs.


Asunto(s)
Nanopartículas Magnéticas de Óxido de Hierro , Polímeros , Cápsulas , Campos Magnéticos , Ingeniería de Tejidos
16.
Int J Bioprint ; 6(3): 304, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33088991

RESUMEN

Scaffolding is the conceptual framework of conventional tissue engineering. Over the past decade, scaffold-free approaches as a potential alternative to classic scaffold-based methods have emerged, and scaffold-free magnetic levitational tissue engineering (magnetic force-based tissue engineering [Mag-TE]) is a type of this novel tissue engineering strategy. However, Mag-TE is often based on the use of potentially toxic magnetic nanoparticles. Scaffold-free and label-free magnetic levitational bioassembly do not employ magnetic nanoparticles and thus, the potential toxicity of magnetic nanoparticles can be avoided. In this short review, we describe the conceptual foundation of scaffold-free, label-free, and nozzle-free formative biofabrication using magnetic fields as "scaffields." The design and implementation of "Organ.Aut," the first commercial magnetic levitational bioassembler, and the potential applications of magnetic bioassembler are discussed as well.

17.
Acta Biomater ; 118: 141-152, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33045401

RESUMEN

Cytoskeleton systems, actin microfilaments, microtubules (MTs) and intermediate filaments (IFs) provide the biomechanical stability and spatial organization in cells. To understand the specific contributions of each cytoskeleton systems to intrinsic properties of spheroids, we've scrutinized the effects of the cytoskeleton perturbants, cytochalasin D (Cyto D), nocodazole (Noc) and withaferin A (WFA) on fusion, spreading on adhesive surface, morphology and biomechanics of chondrospheres (CSs). We confirmed that treatment with Cyto D but not with Noc or WFA severely affected CSs fusion and spreading dynamics and significantly reduced biomechanical properties of cell aggregates. Noc treatment affected spheroids spreading but not the fusion and surprisingly enhanced their stiffness. Vimentin intermediate filaments (VIFs) reorganization affected CSs spreading only. The analysis of all three cytoskeleton systems contribution to spheroids intrinsic properties was performed for the first time.


Asunto(s)
Citoesqueleto , Filamentos Intermedios , Citoesqueleto de Actina , Microtúbulos , Vimentina
18.
Biotechnol J ; 15(5): e1900217, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31995658

RESUMEN

Reproducible, scalable, and cost effective fabrication and versatile characterization of tissue spheroids (TS) is highly demanded by 3D bioprinting and drug discovery. Consistent geometry, defined mechanical properties, optimal viability, appropriate extracellular matrix/cell organization are required for cell aggregates aimed for application in these fields. A straightforward procedure for fabrication and systematic multiparametric characterization of TS with defined properties and uniform predictable geometry employing non-adhesive technology is suggested. Applying immortalized and primary cells, the reproducibility of spheroid generation, the strong correlation of ultimate spheroid diameter, and growth pattern with cell type and initial seeding concentration are demonstrated. Spheroids viability and mechanical properties are governed by cell derivation. In this study, a new decision procedure to apply for any cell type one starts to work with to prepare and typify TS meeting high quality standards in biofabrication and drug discovery is suggested.


Asunto(s)
Biomarcadores/metabolismo , Esferoides Celulares/citología , Ingeniería de Tejidos/métodos , Animales , Bioimpresión , Línea Celular , Supervivencia Celular , Fibroblastos/citología , Fibroblastos/metabolismo , Células HEK293 , Humanos , Ratas , Esferoides Celulares/metabolismo
19.
Cartilage ; 11(4): 521-531, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-30221989

RESUMEN

OBJECTIVE: Chondrospheres represent a variant of tissue spheroids biofabricated from chondrocytes. They are already being used in clinical trials for cartilage repair; however, their biomechanical properties have not been systematically investigated yet. The aim of our study was to characterize chondrospheres in long-term in vitro culture conditions for morphometric changes, biomechanical integrity, and their fusion and spreading kinetics. RESULTS: It has been demonstrated that the increase in chondrospheres secant modulus of elasticity is strongly associated with the synthesis and accumulation of extracellular matrix. Additionally, significant interplay has been found between biomechanical properties of tissue spheroids and their fusion kinetics in contrast to their spreading kinetics. CONCLUSIONS: Extracellular matrix is one of the main structural determinants of chondrospheres biomechanical properties during chondrogenic maturation in vitro. The estimation of tissue spheroids' physical behavior in vitro prior to operative treatment can be used to predict and potentially control fusogenic self-assembly process after implantation in vivo.


Asunto(s)
Condrocitos/citología , Condrogénesis/fisiología , Matriz Extracelular/fisiología , Esferoides Celulares/fisiología , Ingeniería de Tejidos , Fenómenos Biomecánicos , Células Cultivadas , Humanos , Técnicas In Vitro
20.
Sci Rep ; 10(1): 4013, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-32132636

RESUMEN

The calcium phosphate particles can be used as building blocks for fabrication of 3D scaffolds intended for bone tissue engineering. This work presents for the first time a rapid creation of 3D scaffolds using magnetic levitation of calcium phosphate particles. Namely, tricalcium phosphate particles of equal size and certain porosity are used, which undergo the process of recrystallization after magnetic levitational assembly of the scaffold to ensure stitching of the scaffold. Label-free levitational assembly is achieved by using a custom-designed magnetic system in the presence of gadolinium salts, which allows the levitation of calcium phosphate particles. Chemical transformation of tricalcium- to octacalcium phosphate under the condition of magnetic levitation in non-homogeneous magnetic field is also demonstrated. This approach allows obtaining rapidly the octacalcium phosphate phase in the final 3D product, which is biocompatible.


Asunto(s)
Regeneración Ósea , Huesos/metabolismo , Fosfatos de Calcio/química , Campos Magnéticos , Impresión Tridimensional , Andamios del Tejido/química , Huesos/citología , Niño , Preescolar , Femenino , Humanos , Masculino , Porosidad
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