ISMAR NEWTON CESTARI
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/65, Hospital das Clínicas, Faculdade de Medicina
LIM/65, Hospital das Clínicas, Faculdade de Medicina
6 resultados
Resultados de Busca
Agora exibindo 1 - 6 de 6
- Assessment of the biocompatibility of the PLLA-PLCL scaffold obtained by electrospinning(2015) OYAMA, Helena T. T.; CORTELLA, Lucas R. X.; ROSA, Isabela N. S.; FILHO, Leonardo E. R.; HUI, Wang S.; CESTARI, Ismar N.; CESTARI, Idagene A.Electrospun membranes of poly (L-Lactide) / poly (L-lactide-co-caprolactone) blend were produced and evaluated by physical and mechanical tests to use as a scaffold for cell growth. The membranes were seeded with endothelial cells (HUVEC) and after culturing time it was visualized by confocal laser scanning microscopy and scanning electron microscopy. The results indicate that the process parameters were capable of producing PLLA-PLCL membranes presenting fibers with diameters in the nanometer range. The scaffolds supported cell attachment and growth, indicating the feasibility of producing scaffolds by electrospinning technique, which could be used in tissue engineering applications. (C) 2015 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of IDMEC-IST.
- Surface Topography Obtained with High Throughput Technology for hiPSC-Derived Cardiomyocyte Conditioning(2022) CORTELLA, Lucas R. X.; CESTARI, I. A.; S, M.; MAZZETTO, M.; LASAGNI, A. F.; CESTARI, Ismar N.The use of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) to replace myocardial tissue after an infarct holds great promises. However, hiPSC-CM are phenotypically immature when compared to cells in the adult heart, hampering their clinical application. We aimed to develop and test a surface structuring technique that would improve hiPSC-CM structural maturation. Laser ablation was used to fabricate a micron-pattern on polyurethane surface and evaluated cell morphology, orientation and F-actin assemblage to detect phenotypic changes in response to the microtopography. This topography positively influenced cell morphology regarding to spreading area and elongation, and hiPSC-CM orientation, improving their structural maturation. The methodology thus presented has relatively low cost and is easily scalable, making it relevant for high-throughput applications such as drug screening for the pharma industry.
- Design and Hydrodynamic Performance of a Pediatric Pulsatile Pump(2019) CESTARI, I. A.; MAZZETTO, M.; OYAMA, H. T. T.; BACHT, S.; JATENE, M. B.; CESTARI, I. N.; JATENE, F. B.We report the design and hydrodynamic performance of a pulsatile blood pump and a pneumatic driver system to treat pediatric patients in need of circulatory support while waiting for a heart transplant. The blood pump consists of a pumping chamber with 15 ml stroke volume separated by a flexible diaphragm from a pneumatic chamber. The blood chamber has two orifices fitted with rings in which tri-leaflet tissue valves are placed to control the inflow and outflow of blood. Blood contacting surfaces are heparin coated. The driving unit allows operation of two pumps to assist the left and right side of the heart, independently or simultaneously in three different modes of operation: full-to-empty, ECG synchronized and asynchronous. The flow generated by the pump increases with preload and application of auxiliary negative pressure during the filling phase reaching approximately 1,6 L/min when the pump is operating in full-to-empty mode. The results suggest the performance of the pediatric VAD designed is compatible with the needs of pediatric patients up to 15 kg body weight.
conferenceObject Computational tool for morphological analysis of cultured neonatal rat cardiomyocytes(2015) LEITE, Maria Ruth C. R.; CESTARI, Idagene A.; CESTARI, Ismar N.This study describes the development and evaluation of a semiautomatic myocyte edge-detector using digital image processing. The algorithm was developed in Matlab 6.0 using the SDC Morphology Toolbox. Its conceptual basis is the mathematical morphology theory together with the watershed and Euclidean distance transformations. The algorithm enables the user to select cells within an image for automatic detection of their borders and calculation of their surface areas; these areas are determined by adding the pixels within each myocyte's boundaries. The algorithm was applied to images of cultured ventricular myocytes from neonatal rats. The edge-detector allowed the identification and quantification of morphometric alterations in cultured isolated myocytes induced by 72 hours of exposure to a hypertrophic agent (50 mu M phenylephrine). There was a significant increase in the mean surface area of the phenylephrine-treated cells compared with the control cells (p<0.05), corresponding to cellular hypertrophy of approximately 50%. In conclusion, this edge-detector provides a rapid, repeatable and accurate measurement of cell surface areas in a standardized manner. Other possible applications include morphologic measurement of other types of cultured cells and analysis of time-related morphometric changes in adult cardiac myocytes.- Experimental Apparatus for Evaluation of Calcium Fluctuations in Cardiomyocytes Derived from Human-Induced Pluripotent Stem Cells(2022) ARANA, M. C.; LAHUERTA, R. D.; CORTELLA, L. R. X.; MAZZETTO, M.; SOLDERA, M.; LASAGNI, A. F.; CESTARI, I. N.; CESTARI, I. A.In this work, we developed and tested an experimental apparatus to evaluate calcium fluctuations in cardiomyocytes derived from human-induced pluripotent stem cells (hiPSC-CM). The set-up is composed of a signal module for registration and analysis of the signals and a perfusion chamber. This chamber allows the maintenance of the cells, control of perfusion and temperature, and electric stimulation. The signal module consists of a CCD camera attached to a fluorescence microscope with the appropriate software and hardware for eliciting and recording fluorescent signals originating from hiPSC-CM intracellular Ca+2 concentration changes, under electrical stimulation. We employed this system for analysis of calcium fluctuation from hiPSC-CM cultivated on micro textured polyethylene terephthalate surfaces.
- Experimental Method for Recording Epicardium Potentials and Cardiac Myocyte Shortening(2017) MARCHINI, Gustavo S.; TAMASHIRO, Daniel S. U.; OYAMA, Helena T.; CORTELLA, Lucas; CESTARI, Ismar N.; CESTARI, Idagene A.The hemodynamic changes observed in advanced stages of heart diseases are often accompanied by changes in the electrical and mechanical properties of cardiac myocytes. The objective of this work is to develop an experimental method for recording ventricle epicardium potentials in isolated rat hearts and isolated cardiac myocyte shortening. Briefly, rat heart was removed, aorta was cannulated and coronary arteries were retrogradely perfused with heated and oxygenated buffer solutions. Ag-AgCl electrodes fixed in a silicone pouch placed around the heart were used to measure epicardium potentials. The perfusion was switched to an enzyme-containing solution for digestion of the heart and obtaining isolated cardiac myocytes. Measurements of shortening were made in cells electrically stimulated. The results suggest the possibility of relating the electrical behavior of the whole heart with mechanical properties of cardiac myocytes and may represent an useful tool in basic cardiac research.