Morfofunctional characterization of mother cells of dental fabrics in culture. Bioestimulation with laser. “In vitro” test.

Los objetivos de este trabajo fueron: Caracterizar morfológica y funcionalmente células madre mesenquimales (CMM) de pulpa, evaluar distintos métodos de cultivo y establecer un método de irradiación con laser de las células cultivadas. Se utilizaron terceros molares obtenidos en el Hospital Universitario con consentimiento del paciente y aprobación de Comité de Bioética de la FOLP-UNLP. Extraídas las piezas, se trasladaron al Laboratorio de Biología Molecular y Biotecnología de la FOLPUNLP. Se ensayaron distintos métodos de obtención y aislamiento de células: 1. digestión enzimática 2. obtención de explantos. Las células fueron caracterizadas mediante el estudio de marcadores de superficie específicos de CM, como CD73, CD90, CD105 y CD146 por citometría de flujo (Citometer BD FAC SCalibur), se estudiaron morfológicamente las células mediante MET y microscopio invertido con contraste de fases (Leica mod.DM IL LED). Posteriormente se cultivaron 5x 10 4 células en cada placa de Petri de 35 mm de diámetro (día 0). Luego de 24 horas (día 1) las placas fueron divididas en 3 grupos: G1.8: se aplicó densidad energética de 1.79 J/cm2,G3.6: se aplicó densidad energética de 3.57 J/cm 2,GC: Sin irradiación. Se utilizó laser diodo de 940 nm, con potencia regulada a 1W a t:48 y 72 hs. Morfológicamente se evidenciaron mitocondrias, vesículas y gránulos de secreción. En cultivo se observaron colonias de células fusiformes y estrelladas, formando agregados. La caracterización fenotípica por citometría de flujo para marcadores CD73, CD90, CD105 y CD146 resulto positiva. El método de irradiación con laser pudo adaptarse a los procesos de cultivo utilizados en el laboratorio. Se ha puesto a punto un eficiente método de obtención de CMM dentales, y podemos concluir que el mejor método para obtención, aislamiento y expansión es el del explanto. La morfología celular es un buen indicador de la calidad y desarrollo del cultivo.The objectives of this work were: Morphologically and functionally characterize pulp mesenchymal stem cells (CMM), evaluate different culture methods and establish a low frecuency laser irradiation methods for cultures. Third molars obtained at the University Hospital with the patient's consent and approval of the Bioethics Committee of the FOLP-UNLP was used. Once the pieces were removed, they were transferred to the Molecular Biology and Biotechnology Laboratory of the FOLP-UNLP. Different methods of obtaining and isolating cells were tested: 1. enzymatic digestion obtaining explants. The cells were characterized by studying specific surface markers of CM, such as CD73, CD90, CD105 and CD146 by flow cytometry (Citometer BD FAC SCalibur), the cells were morphologically studied by MET and inverted microscope with phase contrast (Leica mod.DM IL LED). Subsequently, 5 x 10 4 cells were cultured in each 35 mm diameter Petri dish (day 0). After 24 hours (day 1) the plates were divided into 3 groups: G1.8: 1.79 J / cm2 energy density was applied, G3.6: 3.57 J / cm 2 energy density was applied, GC: No irradiation. 940 nm diode laser was used, with regulated power at 1W at t: 48 and 72 hours. Morphologically, mitochondria, vesicles and secretion granules were evidenced. In culture, colonies of fusiform and star cells were observed, forming aggregates. The phenotypic characterization by flow cytometry for markers CD73, CD90, CD105 and CD146 was positive. The laser irradiation method was suitable to be used in the laboratory culture procedures. An efficient method of obtaining dental CMM has been developed, and we can conclude that the best method for obtaining, isolating and expanding is that of the explant. Cellular morphology is a good indicator of crop quality and development.Facultad de Odontologí

Sulfonation of Polyether-Ether Ketone dental implants (PEEK)

Desde hace tres décadas el polieter-etercetona está siendo utilizado para la elaboración de implantes biomédicos. A partir del año 2000, comenzó a aplicarse en Europa en la confección de los implantes dentales. Desde entonces, su composición química ha sido combinada con otros elementos para su mejor adaptación al tejdo óseo. El objetivo de este trabajo fue someter al tratamiento de sulfonación a los implantes dentales de PEEK para poder determinar la mejoría de porosidad que presentan estos en su superficie. Para ello, se confeccionaron probetas previamente arenadas para introdocir en ellas cuatro implantes de polieteretercetona. Los mismos, fueron tratados con un grupo sulfónico y carbono (sulfonación), con simple y doble inmersión según el caso. Posteriormente, se analizó la composición química de los mismos, mediante EDAX (Difracción de rayos X). Luego, se realizaron observaciones por Microscopía Electrónica de Barrido y de Transmisión, para medir el tamaño de las porosidades del material, y registrar los cambios producidos por la sulfonación. Los resultados, arrojaron una Media de 55 μm de porosidad. Del trabajo se infiere que el tratamiento de sulfonación sobre los implantes de PEEK, podrían aumentar la rugosidad compatible con la del hueso alveolar, más que el tratamiento de sulfonación.For three decades polyether ether ketone is being used for the elaboration of biomedical imlants. From the year 2000, it began to be applied in Europe in the manufacturing of dental implants. Since then, its chemical composition has been combined with other elements for better adaptation to bone tissue. The objective of this work was to undergo sulfonation treatment to PEEk dental implants in order to determine the improvement of porosity that these present on their surface. For this, previously sandblasted specimens were made to introduce four implants of polyetherether ketone into them. They were treated with a sulfonic and carbon group (sulfonation), with single and double immersion as appropriate. Subsequently, their chemical composition was analyzed by means of EDAX (X-ray diffraction). Then, observations were made by Scanning and Transmission Electron Microscopy, to measure the size of the porosities of the material, and record the changes produced by the sulfonation. The results yielded an average of 55 μm of porosity. From the work it is inferred that the sulfonation treatment on PEEK implants could increase the roughness compatible with that of the alveolar bone, rather than the sulfonation treatment.Facultad de Odontologí

Étude médicale du glycérophosphate de quinine

Thèse : Médecine : Université de Bordeaux : 1900N° d'ordre : 9

Recreating life? The osmosis effects [Recréer la vie?: Effets d'osmose]

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UV-Photoelectron Spectroscopy of Organosilicon Compounds

International audienceThis chapter describes key work performed in the last 15 years, in which the use of the ultraviolet-photoelectron spectroscopy (UV-PES) has made significant progress in the understanding of various phenomena, such as hyperconjugation or other interactions due to high-energy σ bonds (Si–C, Ge–C, Si–Si, etc.), neutral cyclic cross hyperconjugation, influence of substituents on the stability of Si=C bond, or structure of the low-valent group 14 element analogues of carbenes and radicals. The knowledge of the electronic structure of compounds of interest allows not only comprehension and explanation of their reactivity or physical chemistry properties but provides an essential tool for the prediction and design of new compounds designed for specific properties. UV-PES is certainly a key tool to consider in the search for information on the electronic structure of molecules. Short descriptions of the UV-photoelectron spectrometer for gas phase characterization and theoretical methods for the evaluation of ionization energies are also given

A Theoretical and Experimental Approach for Electronic Structure Characterization of BN Isosteres of Anthracene.

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Ab initio calculation of the nonlinear susceptibility χ(2) of a crystal surface.

International audienceThe polarizability and 1st hyperpolarizability of a crystal surface were calcd. from a sum over states method using cryst. orbitals of the CRYSTAL program. The linear and nonlinear optical properties of the (001) LiF surfaces are evaluated layer by layer, showing that the response of inner layers to an elec. field tends effectively to the bulk response value while the χ(2) susceptibility components responsible of 2nd harmonic generation (SHG) are no longer equal to zero at the surface of the crystal