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2.
Development ; 145(3)2018 02 08.
Article in English | MEDLINE | ID: mdl-29386244

ABSTRACT

The three-dimensional architecture of the pancreatic islet is integral to beta cell function, but the process of islet formation remains poorly understood due to the difficulties of imaging internal organs with cellular resolution. Within transparent zebrafish larvae, the developing pancreas is relatively superficial and thus amenable to live imaging approaches. We performed in vivo time-lapse and longitudinal imaging studies to follow islet development, visualizing both naturally occurring islet cells and cells arising with an accelerated timecourse following an induction approach. These studies revealed previously unappreciated fine dynamic protrusions projecting between neighboring and distant endocrine cells. Using pharmacological compound and toxin interference approaches, and single-cell analysis of morphology and cell dynamics, we determined that endocrine cell motility is regulated by phosphoinositide 3-kinase (PI3K) and G-protein-coupled receptor (GPCR) signaling. Linking cell dynamics to islet formation, perturbation of protrusion formation disrupted endocrine cell coalescence, and correlated with decreased islet cell differentiation. These studies identified novel cell behaviors contributing to islet morphogenesis, and suggest a model in which dynamic exploratory filopodia establish cell-cell contacts that subsequently promote cell clustering.


Subject(s)
Islets of Langerhans/growth & development , Islets of Langerhans/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Zebrafish Proteins/metabolism , Zebrafish/growth & development , Zebrafish/metabolism , Actin Cytoskeleton/metabolism , Animals , Animals, Genetically Modified , Cell Aggregation , Cell Movement , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/metabolism , Islets of Langerhans/cytology , Keratin-18/genetics , Keratin-18/metabolism , Organogenesis , Phosphoinositide-3 Kinase Inhibitors , Pseudopodia/metabolism , Pseudopodia/ultrastructure , Receptors, G-Protein-Coupled/antagonists & inhibitors , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Signal Transduction , Single-Cell Analysis , Zebrafish/genetics , Zebrafish Proteins/antagonists & inhibitors , Zebrafish Proteins/genetics , rac1 GTP-Binding Protein/antagonists & inhibitors , rac1 GTP-Binding Protein/metabolism
3.
Found Comut Math ; 18(4): 891-927, 2018.
Article in English | MEDLINE | ID: mdl-30956649

ABSTRACT

A shape sensitive, variational approach for the matching of surfaces considered as thin elastic shells is investigated. The elasticity functional to be minimized takes into account two different types of nonlinear energies: a membrane energy measuring the rate of tangential distortion when deforming the reference shell into the template shell, and a bending energy measuring the bending under the deformation in terms of the change of the shape operators from the undeformed into the deformed configuration. The variational method applies to surfaces described as level sets. It is mathematically well-posed, and an existence proof of an optimal matching deformation is given. The variational model is implemented using a finite element discretization combined with a narrow band approach on an efficient hierarchical grid structure. For the optimization, a regularized nonlinear conjugate gradient scheme and a cascadic multilevel strategy are used. The features of the proposed approach are studied for synthetic test cases and a collection of geometry processing examples.

4.
Span J Psychol ; 14(2): 926-35, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22059336

ABSTRACT

The Affective Neuroscience Personality Scales have been designed to provide a personality assessment tool based on six distinct affective systems. The six neural systems involved were labeled PLAY, SEEK, CARE, FEAR, ANGER and SADNESS. Spirituality has been integrated into the questionnaire as a seventh dimension because, in opinion of Panksepp and his colleagues is one of the most interesting human emotion. The aim of the present paper was introduce the validation of the Spanish version of Affective Neuroscience Personality Scales and their first psychometric results in a sample of 411 college students. Participants completed the Spanish version of ANPS, just as a personality scale of five factors (NEO-FFI-R), and the Scales of Positive and Negative Affect (PANAS). The factor structure obtained and psychometric properties of the scales indicate that the Spanish version of the scales provides an effective tool to measure the seven dimensions of personality proposal in the original questionnaire.


Subject(s)
Affect/physiology , Cross-Cultural Comparison , Emotions/physiology , Neurosciences , Personality Assessment/statistics & numerical data , Adolescent , Adult , Brain/physiology , Female , Humans , Male , Personality Inventory/statistics & numerical data , Psychometrics/statistics & numerical data , Reference Values , Reproducibility of Results , Sex Factors , Spain , Spirituality , Translating , Young Adult
5.
Span. j. psychol ; 14(2): 926-935, nov. 2011. tab
Article in English | IBECS | ID: ibc-91232

ABSTRACT

The Affective Neuroscience Personality Scales have been designed to provide a personality assessment tool based on six distinct affective systems. The six neural systems involved were labeled PLAY, SEEK, CARE, FEAR, ANGER and SADNESS. Spirituality has been integrated into the questionnaire as a seventh dimension because, in opinion of Panksepp and his colleagues is one of the most interesting human emotion. The aim of the present paper was introduce the validation of the Spanish version of Affective Neuroscience Personality Scales and their first psychometric results in a sample of 411 college students. Participants completed the Spanish version of ANPS, just as a personality scale of five factors (NEO-FFI-R), and the Scales of Positive and Negative Affect (PANAS). The factor structure obtained and psychometric properties of the scales indicate that the Spanish version of the scales provides an effective tool to measure the seven dimensions of personality proposal in the original questionnaire (AU)


Las Escalas de Personalidad Neuroafectivas han sido diseñadas con la intención de proporcionar una herramienta de evaluación de la personalidad a partir de seis sistemas afectivos bien diferenciados. Los seis sistemas neuronales implicados se han denominado JUEGO, BÚSQUEDA, CUIDADOS, MIEDO, IRA y TRISTEZA. Espiritualidad se ha integrado en el cuestionario como una séptima dimensión debido a que según consideran Panksepp y sus colaboradores es una de las emociones humanas de mayor interés. En este trabajo se presenta la validación española de las Escalas de Personalidad Neuroafectiva y sus primeros resultados psicométricos en una muestra de 412 estudiantes universitarios. Los participantes completaron la versión española de las ANPS, así como una escala de personalidad de cinco factores (NEO-FFI-R) y las Escalas de Afecto Positivo y Negativo (PANAS). La estructura factorial obtenida y las propiedades psicométricas de las escalas indican que la versión española de las escalas se presenta como una herramienta psicométrica eficaz para evaluar las siete dimensiones de la personalidad desde un punto de vista afectivo (AU)


Subject(s)
Humans , Male , Female , Adult , Personality/physiology , Psychological Tests/statistics & numerical data , Psychological Tests/standards , Affect/physiology , Fear/psychology , Anger/physiology , Psychometrics/methods , Psychometrics/trends , Spirituality , Surveys and Questionnaires , Psychiatric Status Rating Scales/statistics & numerical data , Psychiatric Status Rating Scales/standards , Spain/epidemiology
6.
Rev. venez. cir. ortop. traumatol ; 38(1): 7-12, jun. 2006. tab, graf
Article in Spanish | LILACS | ID: lil-513411

ABSTRACT

Se realizó un estudio prospectivo, retrospectivo y comparativo en 47 pacientes con fracturas intertrocantéricas de fémur tratadas con P.F.N. y D.H.S. en el Hospital Central de Maracay durante los años 2001 al 2004 para establecer cual de los dos métodos ha reportado: menos complicaciones intraoperatorias, una una deambulación temprana y consiguió consolidación de la fractura en menos tiempo. Hubo incidencia del 70,2 por ciento en mujeres, el promedio de edad fue 72 años, el 93,6 por ciento fueron debidas a las caídas a sus pies. El tipo de fractura más frecuente fue la 3,1-A2. Los pacientes tratados con P.F.N. presentaron menos tiempo quirúrgico, alcanzaron la marcha asistida e independiente más rápida y un tiempo de consolidación menos que el grupo tratado con D.H.S. Concluimos que el P.F.N. presenta mayores ventajas que el D.H.S. en el tratamiento de estas fracturas con mejores resultados.


Subject(s)
Humans , Male , Adult , Female , Middle Aged , Bone Nails , Hip Fractures/diagnosis , Hip Fractures/therapy , Femoral Fractures/diagnosis , Femoral Fractures/therapy , Orthopedics , Radiography , Traumatology
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