Influence of adhesive systems on microtensile bond strength of resin-based endodontic sealers to the root dentin

Objective: The aim of this study was to determine the microtensile bond strength to root dentin of AH PlusTM and EndoREZ® with Clearfil Liner Bond 2V and Optibond SoloTM Plus adhesive systems. Study Design: The coronal and middle thirds of six single rooted bovine teeth was split longitudinally in a mesio- distal direction. The two halves were joined with AH Plus or EndoREZ, with and without the use of Clearfil Li - ner Bond 2V and Optibond SoloTM Plus adhesive systems. Build-ups were vertically sectioned into quadrangular (?1mmx1mm) compound bars and subjected to tensile tests at a constant crosshead speed (1 mm/min) until debon - ding. Results: Optibond ® Solo PlusTM in combination with AH PlusTM and EndoREZ ® showed the highest mean micro - tensile bond strength values, in both coronal and middle thirds. The lowest results were seen in the groups where no dentine adhesive was applied, and in those where the self-etching adhesive Clearfil Liner Bond 2V was used. Conclusion: The microtensile bond strength to root dentin of AH PlusTM and EndoREZ may be increased with the use of a total-etch adhesive

Educación inclusiva, obligaciones del Estado Mexicano

Las Niñas, Niños y Adolescentes (NNyA), como parte estructural sensible de una sociedad, se encuentra identificada bajo la premisa de máxima protección por parte del estado, obedeciendo la circunstancia de la minoría de edad, en esa tesitura el desarrollo físico y psicológico es determinante en las políticas públicas establecidas o visualizadas como áreas de oportunidad para su atención. Dentro de los diversos núcleos que integran una sociedad, en el cual se identifican sub grupos, se acuña una realidad identificable, es decir, la minoría de edad la visualizamos como un macro dentro de la colectividad y un micro se considera a quienes tienen la minoría de edad con una limitante física, es a lo que se le denomina como diversidad funcional. En una sociedad, entender y valorar la diversidad funcional en menores de edad significa reconocer y respetar la individualidad de cada niño y niña, y proporcionarles oportunidades y recursos adecuados para su desarrollo y bienestar. Esto puede incluir la inclusión en la educación regular, la adaptación de materiales y metodologías de enseñanza, y la disponibilidad de servicios y apoyos especializados, identificando conductas sociales que los colocan en grados de vulnerabilidad e invisibilidad, la disyuntiva que se observa corresponde en determinar que son considerados como vulnerables por la edad sufriendo diversas discriminaciones en el acceso a la educación, ya que la misma no se adecua a ellos, lo cual ha provocado que se violente el derecho humano a la educación. Lo anterior genera la necesidad de exigir al estado mexicano una educación inclusiva en donde se garantice el acceso al sistema de educación general para les NNyA, por ello el presente artículo expone la necesidad de encontrar acomodo en él mediante una pedagogía centrada en los NNyA, a través de ajustes razonables y los cuales deberían ser acordes al principio de igualdad, sin generar un efecto estigmatizante y evitar así que se violente el derecho a la educación inclusiva

Dynamic changes of the extracellular matrix during corneal wound healing

Producción CientíficaThe extracellular matrix (ECM) confers transparency to the cornea because of the precise organization of collagen fibrils and a wide variety of proteoglycans. We monitored the corneal wound healing process after alkali burns in rabbits. We analyzed the location and expression of collagens and proteoglycans, the clinical impact, and the recovery of optical transparency. After the animals received both general and ocular topical anesthesia, the central cornea of the left eye was burned by placing an 8-mm diameter filter paper soaked in 0.5 N NaOH for 60 s. The eyes were evaluated under a surgical microscope at 1, 3, and 6 months after burning. At each time point, the clinical conditions of the burned and control corneas were observed. The arrangement of collagen fibers in the corneal stroma was visualized by Picrosirius-red staining, Gomori's silver impregnation and transmission electronic microscopy. Corneal light transmittance was also measured. Myofibroblasts presence was analyzed by immunohistochemistry. mRNA expression levels of collagen types I and III, lumican, decorin, keratocan and alpha-smooth muscle actin were determined by quantitative real-time polymerase chain reaction. One month after alkali burn, the ECM was disorganized and filled with lacunae containing different types of cells and collagen type III fibers in the wound area. Corneal opacities were present with attendant loss of light transmittance. Collagen and proteoglycan mRNA expression levels were up-regulated. After three months, wound healing progress was indicated by reduced corneal opacity, increased light transmittance, reorganization of collagen fibers and only collagen type I expression levels were at control levels. After six months, the wound area ECM morphology was similar to controls, but transmittance values remained low, denoting incomplete restoration of the stromal architecture. This multidisciplinary study of the stromal wound healing process revealed changes in corneal transmittance, collagen organization, myofibroblasts presence and ECM composition at 1, 3, and 6 months after alkali burning. Documenting wound resolution during the six-month period provided reliable information that can be used to test new therapies.Instituto de Salud Carlos III (Health Research Fund PI15/01906 )Ministerio de Economía, Industria y Competitividad ( project BFU2016-75360-R)Junta de Castilla y León (Project VA114P17

Measurement of correlation between transmission and scattering during wound healing in hen corneas

Producción CientíficaThe aim of this work is to provide experimental data for corneal transparency and scattering to help create a more complete model of corneal transparency. The scattered light in 96 healing hen corneas was measured for three wavelengths by a scatterometer constructed in the Optics Laboratory (The University of Valladolid, Spain). With the help of mirrors and beamsplitters, the light from the three lasers is directed toward the cell containing the sample to be measured. The measured scattered light varies between six orders of magnitude. Corneal transmissivity, mean cosine of a scattering angle, and angular distribution of scattered light were all computed. The total transmitted light remained practically constant over a wide range of light values transmitted in a forward direction (direct transmissivity). The value of the mean cosine of the scattering direction is very close to the unit (g40:98), even in corneas with high opacities. The behavior of g indicates that even damaged corneas evidence extremely small scattering, compared to other biological tissues. The transmission reduction of each cornea is related to an increase in scattered light. In all cases, scattered light is concentrated at very small angles. This behavior is acceptable in corneas that are healthy or which evidence small lesions, but remains in corneas that are severely injured

Implementación de metodologías de evaluación continua: aplicación en la asignatura de Cálculo Numérico

La creación del nuevo Espacio Europeo de Educación Superior, con los consiguientes cambios en la estructura y contenidos de las titulaciones universitarias, ofrece una gran oportunidad para revisar las metodologías de aprendizaje, estando las metodologías de evaluación continua en una creciente expansión. El objetivo de este trabajo es investigar el efecto que tiene en el aprendizaje de los estudiantes diferentes metodologías de evaluación continua. Para ello, varios tipos de evaluación periódica (entrega de trabajos grupales y/o individuales, exámenes parciales, etc.) han sido puestos en práctica en la asignatura de Cálculo Numérico del último curso de la Licenciatura de Matemáticas y actual Grado de Matemáticas, a lo largo de un total de 14 años académicos en la Universidad de Alicante. En esta comunicación presentaremos las diferentes estrategias de desarrollo de los contenidos de la asignatura así como la forma de evaluación de los mismos. Además, se hará un análisis descriptivo de los resultados obtenidos con las distintas metodologías empleadas y se recogerán propuestas de mejora de cara al próximo curso

Evaluación de la sensibilidad en distintas viníferas blancas: mildiu, oídio y botrytis

6 páginas, 6 figuras.--Trabajo publicado en revista de divulgación científica.Peer reviewe

Una variedad blanca (Vitis vinifera L.) de alto interés comercial, y en vías de extinción. Sinonimias y homonimias

Comunicación presentada al X Congreso Nacional de Ciencias Hortícolas, celebrado en Pontevedra en mayo de 2003.Peer reviewe

Variability of the stomata among 'Albariño' (Vitis vinifera L.) clones and its relationship with susceptibility to downy mildew

In grapevines the stomata are located on the abaxial epidermis of the leaves, arranged in no specific order. As in other plants, they regulate the communication between the internal tissues and the external atmosphere, playing a critical role in both photosynthesis and transpiration processes. Moreover, stomata are the main entrance for pathogens such as Plasmopara viticola (Berk & Curt.)Berl. & de Toni, the causal agent of downy mildew, one of the most widespread fungal diseases of grapevines. Due to this and the fact that downy mildew causes large losses in yield and quality of grapes, there is a great interest to determine the causes of the different degree of susceptibility to this pathogen. Some authors have searched for anatomical features that might be related to the penetration and development of P. viticola in the mesophyll of grapevine leaves, such as the density of leaf hairs (KORTEKAMP and ZYPRIAN, 1999) or the ultrastructure of stomata (JÜRGES et al. 2009). Other authors have examined the differences concerning the number of stomata in different grapevine cultivars (DÜRING 1980, PALLIOTTI et al. 2000, BEN SALEM-FNAYOU et al. 2005), but none had evaluated the differences for this aspect between clones of the same cultivar. Recently some authors have found a strong correlation between the number and size of stomata and the susceptibility to downy mildew (LU et al. 2010). The aim of this work is to determine whether different clones of 'Albariño' differ in terms of their number and size of stomata and its possible relation with the different susceptibility to P. viticola of these same clones.Financial support from the Xunta de Galicia Research Projects (07MRU024403PR).Peer reviewe

The antioxidant effects of soybean lecithin- or low-density lipoprotein-based extenders for the cryopreservation of brown-bear (Ursus arctos) spermatozoa

P. 1185-1193Egg yolk low-density lipoproteins (LDL) and soybean lecithin were evaluated as replacements for egg yolk in extenders used for the cryopreservation of brown-bear spermatozoa. The motility, viability and acrosomal status of post-thawed spermatozoa were analysed, and an egg-yolk extender was used as a control. The total antioxidant capacity of these extenders was tested. Soybean lecithin showed an effect that was dependent on the soybean concentration (2%, 3.5% and 5%) and source (Type A: 24% l-α-phosphatidylcholine, and Type B: 14–23% l-α-phosphatidylcholine). Only semen cryopreserved with 5% Type A soybean exhibited a sperm motility similar to that of semen cryopreserved in egg-yolk-based extender after thawing, although the sperm viability and acrosome status were not as high. Semen frozen in an extender containing LDL (10–15%) exhibited improved sperm viability in comparison with the control, but sperm motility was lower. The LDL-based extender exhibited a higher anti-oxidant activity than the egg-yolk extender and soy lecithin-based extenders. The extenders with higher anti-oxidant activity showed improvements in frozen sperm viability but lower semen motility. These results indicate that soybean lecithin did not have the same protective effect as egg yolk during the freezing of brown-bear spermatozoa but suggest that LDL (10–15%) could be a useful substitute for egg yolk in these extenders