570 research outputs found

    Automated optimal design of wells for electromagnetic cell stimulation

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    In the paper, a device for in vitro electromagnetic stimulation of cells at low frequency (75 Hz) is considered. In particular, shape and position of a well-plate are identified in order to obtain a homogeneous stimulation and to maximize the space allotted to cell culture. To this end, the BiMO and micro-BiMO optimization algorithms, which have shown good performances in multi-objective optimization of electromagnetic devices, are applied

    In Vitro Production of Calcified Bone Matrix onto Wool Keratin Scaffolds via Osteogenic Factors and Electromagnetic Stimulus

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    Pulsed electromagnetic field (PEMF) has drawn attention as a potential tool to improve the ability of bone biomaterials to integrate into the surrounding tissue. We investigated the effects of PEMF (frequency, 75 Hz; magnetic induction amplitude, 2 mT; pulse duration, 1.3 ms) on human osteoblast-like cells (SAOS-2) seeded onto wool keratin scaffolds in terms of proliferation, differentiation, and production of the calcified bone extracellular matrix. The wool keratin scaffold offered a 3D porous architecture for cell guesting and nutrient diffusion, suggesting its possible use as a filler to repair bone defects. Here, the combined approach of applying a daily PEMF exposure with additional osteogenic factors stimulated the cells to increase both the deposition of bone-related proteins and calcified matrix onto the wool keratin scaffolds. Also, the presence of SAOS-2 cells, or PEMF, or osteogenic factors did not influence the compression behavior or the resilience of keratin scaffolds in wet conditions. Besides, ageing tests revealed that wool keratin scaffolds were very stable and showed a lower degradation rate compared to commercial collagen sponges. It is for these reasons that this tissue engineering strategy, which improves the osteointegration properties of the wool keratin scaffold, may have a promising application for long term support of bone formation in vivo

    Chronic cypermethrin exposure alters mouse embryonic stem cell growth kinetics, induces Phase II detoxification response and affects pluripotency and differentiation gene expression

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    Worldwide uncontrolled use of synthetic pyrethroids contaminates water and soil leading to health hazards. Cypermethrin (CYP), the most used pyrethroid, induces detrimental effects on adults and embryos at different stages of development of several vertebrate species. In Mammals, CYP-induced alterations have been previously described in adult somatic cells and in post-implantation embryos. It remains unknown whether CYP has effects during pre-implantation development. Studies to access pre-implantation embryo toxicity are complicated by the restricted number of blastocysts that may be obtained, either in vivo or in vitro. Embryonic stem cells (ESCs) are an in vitro model study that overcomes these limitations, as millions of pluripotent cells are available to the analysis. Also, ESCs maintain the same pluripotency characteristics and differentiation capacity of the inner cell mass (ICM) present in the blastocyst, from which they derive. In this work, using mouse R1 ESCs, we studied CYP-induced cell death, ROS production, the activation of oxidative stress-related and detoxification responses and the population growth kinetics following 72 h exposure at the 0.3 mM LD50 dose. Also, the expression levels of pluripotency genes in exposed ESCs and of markers of the three germ layers after their differentiation into embryoid bodies (EBs) were determined. Two apoptotic waves were observed at 12-24 h and at 72 h. The increase of ROS production, at 24 h until the end of the culture period, was accompanied by the induction, at 48 h, of redox-related Cat, Sod1, Sod2, Gpx1 and Gpx4 genes. Up-regulation of Cyp1b1, but not of Cyp1a1, phase I gene was detected at 72 h and induction of Nqo1, Gsta1 and Ugt1a6 phase II genes began at 24 h exposure. The results show that exposed R1 ESCs activate oxidative stress-related and detoxification responses, although not sufficient, during the culture period tested, to warrant recovery of the growth rate observed in untreated cells. Also, CYP exposure altered the expression of Oct-4 and Nanog pluripotency genes in ESCs and, when differentiated into EBs, the expression of Fgf5, Brachyury and Foxa2, early markers of the ectoderm, mesoderm and endoderm germ layers, respectively. NIH/3T3 cells, a differentiated cell line of embryonic origin, were used for comparison

    Cell Shortening and Calcium Homeostasis Analysis in Adult Cardiomyocytes via a New Software Tool

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    Intracellular calcium (Ca2+) is the central regulator of heart contractility. Indeed, it couples the electrical signal, which pervades the myocardium, with cardiomyocytes contraction. Moreover, alterations in calcium management are the main factors contributing to the mechanical and electrical dysfunction observed in failing hearts. So, simultaneous analysis of the contractile function and intracellular Ca2+ is indispensable to evaluate cardiomyocytes activity. Intracellular Ca2+ variations and fraction shortening are commonly studied with fluorescent Ca2+ indicator dyes associated with microscopy techniques. However, tracking and dealing with multiple files manually is time-consuming and error-prone and often requires expensive apparatus and software. Here, we announce a new, user-friendly image processing and analysis tool, based on ImageJ-Fiji/MATLAB® software, to evaluate the major cardiomyocyte functional parameters. We succeeded in analyzing fractional cell shortening, Ca2+ transient amplitude, and the kinematics/dynamics parameters of mouse isolated adult cardiomyocytes. The proposed method can be applied to evaluate changes in the Ca2+ cycle and contractile behavior in genetically or pharmacologically induced disease models, in drug screening and other common applications to assess mammalian cardiomyocyte functions

    An in vivo Comparison Study Between Strontium Nanoparticles and rhBMP2

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    The osteoinductive property of strontium was repeatedly proven in the last decades. Compelling in vitro data demonstrated that strontium hydroxyapatite nanoparticles exert a dual action, by promoting osteoblasts-driven matrix secretion and inhibiting osteoclasts-driven matrix resorption. Recombinant human bone morphogenetic protein 2 (rhBMP2) is a powerful osteoinductive biologic, used for the treatment of vertebral fractures and critically-sized bone defects. Although effective, the use of rhBMP2 has limitations due its recombinant morphogen nature. In this study, we examined the comparison between two osteoinductive agents: rhBMP2 and the innovative strontium-substituted hydroxyapatite nanoparticles. To test their effectiveness, we independently loaded Gelfoam sponges with the two osteoinductive agents and used the sponges as agent-carriers. Gelfoam are FDA-approved biodegradable medical devices used as delivery system for musculoskeletal defects. Their porous structure and spongy morphology make them attractive in orthopedic field. The abiotic characterization of the loaded sponges, involving ion release pattern and structure investigation, was followed by in vivo implantation onto the periosteum of healthy mice and comparison of the effects induced by each implant was performed. Abiotic analysis demonstrated that strontium was continuously released from the sponges over 28 days with a pattern similar to rhBMP2. Histological observations and gene expression analysis showed stronger endochondral ossification elicited by strontium compared to rhBMP2. Osteoclast activity was more inhibited by strontium than by rhBMP2. These results demonstrated the use of sponges loaded with strontium nanoparticles as potential bone grafts might provide better outcomes for complex fractures. Strontium nanoparticles are a novel and effective non-biologic treatment for bone injuries and can be used as novel powerful therapeutics for bone regeneration

    Розвиток духовності особистості в процесі фахової підготовки майбутніх учителів образотворчого мистецтва

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    (uk) У статті наголошується, що вчитель образотворчого мистецтва виступає носієм не лише спеціальних знань та умінь, але і носієм духовних цінностей. Духовне збагачення і вдосконалення кожної особистості відбувається протягом всього життя в тому числі і в процесі навчання. Гуманізація освіти та естетичне виховання спрямовано на формування гармонійної цілісної особистості, загальнокультурний її розвиток. Засобами естетичного виховання в мистецтві виступає художній образ. Художній образ є відображенням дійсності яке містить в собі не лише суб’єктивний досвід автора, його розуміння та відношення до об’єктів дійсності, але і відбитки культурно-історичного досвіду, естетичних цінностей, але і відбитки культурно-історичного досвіду, естетичних цінностей соціуму загалом. На їх базі і формується всебічно та гармонійно розвинута особистість із вищими моральними цінностями, естетичними канонами та ідеалами.(ru) В статье делается акцент на то, что учитель изобразительного искусства выступает носителем не только специальных знаний и умений, но и носителем духовных ценностей. Духовное обогащение и совершенствование каждой личности происходит на протяжении всей жизни в том числе и в процессе обучения. Гуманизация образования и эстетическое воспитание направлены на формирование гармоничной целостной личности и ее общекультурное развитие. Средством эстетического воспитания в искусстве выступает художественный образ. Художественный образ является отражением действительности, которое содержит в себе не только субъективный опыт автора, его понимание и отношение к объектам действительности, но и отпечатки культурно-исторического опыта, эстетических ценностей социума в целом. На их базе и формируется всесторонне и гармонично развитая личность с высокими моральными ценностями, эстетическими канонами и идеалами.(en) Importance of education in society is determined by the need to raise the national consciousness of the saved and nurturing genuine citizen. Spiritual enrichment and improvement of each individual occurs throughout life including during training. Spirituality determines the direction of all mental, emotional, sensual, strong-willed human qualities and its ability to self yourself as a person. Master of Fine Arts acting carrier not only specialized knowledge and skills, but also a bearer of spiritual values. Humanizing education and aesthetic education aims at forming a harmonious whole person, her general cultural development. Art is an integral part of spiritual culture, a reflection of the artistic representations of the human form of the world of reality. The means of aesthetic education in the art of acting artistic image. Artistic image is a reflection of reality, which contains not only the subjective experience of the author, and understanding related to the objects of reality, but the prints are of cultural and historical experience, the aesthetic values of society as a whole. At their base is formed fully and harmoniously developed personality with higher moral values, aesthetic canons and ideals
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