510 research outputs found

    PIGMENTATION OF THE HEART IN THE BICHIR, POLYPTERUS SENEGALUS

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    El resumen aparece en el Program & Abstracts of the 10th International Congress of Vertebrate Morphology, Barcelona 2013. Anatomical Record, Volume 296, Special Feature — 1: P-078.The presence of melanin-containing cells in the heart has been documented in tetrapods, but not in fish. It has been even suggested that dark pigmented cells are exclusively associated with hearts having two atria and two ventricles. The aim here is to report the occurrence of pigment cells in the heart of the bichir, an extant representative of the polypteriformes, an ancient ray-finned fish lineage that split from the stem of the actinopterygians soon after their divergence from the sarcopterygians. The bichir heart is composed of sinus venosus, atrium, ventricle, conus arteriosus and bulbus arteriosus arranged sequentially within the pericardial cavity. Dendritic-shaped cells containing melanosomes were found in the five cardiac components of the 12 bichirs included in this study. Numerous melanophores were distributed regularly over the surface of all segments having myocardium in their walls, thus resulting in a marked pigmentation of the whole heart. The bulbus arteriosus, which in the bichir is reduced in size, showed an even more intense pigmentation. In all instances, the melanophores were localized in the subepicardial space. Pigment cells also occurred in the pericardium and ventral aorta. The functional role of melanocytes in the tetrapod heart remains obscure. Antiinflamatory activity, cytoprotection and effects on the viscoelastic properties of the cardiac tissue have been adduced as possible actions of such cells. The role of pigment cells in the bichir heart constitutes a new open question. Interestingly, however, the only cells that have been shown to form melanin-containing cells in the heart derive from the neural crest. If the melanophores of the bichir heart are indeed of neural crest origin, it would suggest a much more extensive contribution and persistence of elements from the neural crest in the primitive heart of jawed vertebrates as assumed so far in most papers devoted to vertebrate heart embryology.Proyecto CGL2010-16417/BOS; Fondos FEDER; Beca FPI ref. BES-2011-046901

    Oral health and depressive symptoms: findings from the English Longitudinal Study of Ageing

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    Aim We assessed the cross-sectional association between depressive symptoms and oral health using a nationally representative sample of older adults aged 50 years and older living in England.Methods Data came from wave 7 (2014-2015) of the English Longitudinal Study of Ageing. Multiple logistic regression analyses were conducted to assess the association between depressive symptoms, measured through the eight-item Centre for Epidemiologic Studies Depression Scale and three oral health outcomes, namely self-rated oral health, edentulousness and oral impacts.Results The analytical sample comprised 3,617 individuals. The proportion of participants that reported poor self-rated oral health, being edentate and having at least one oral health impact in the last six months was 19.8%, 7.7% and 8.9%, respectively. Around a tenth of the participants reported having depressive symptoms (10%). All unadjusted associations between depressive symptoms and the oral health measures were statistically significant. However, after accounting for potential confounders, only the relationship between depressive symptoms and self-rated oral health remained significant (OR = 1.38; 95% CI 1.01-1.89). Socioeconomic and general health-related variables appeared to influence the associations between depressive symptoms and oral health, particularly edentulousness and oral impacts.Conclusion Depressive symptoms were associated with poor self-rated oral health in older English adults

    Multimorbidity patterns of oral clinical conditions, social position, and oral health-related quality of life in a population-based survey of 12-yr-old children.

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    The aim of this study was to describe the patterns of multimorbidities of oral clinical conditions in children. The association between social position and number of oral clinical conditions, and the relationship of social position and number of oral clinical conditions with oral health-related quality of life [OHRQoL, measured using the Brazilian Child-Oral Impacts on Daily Performance (Child-OIDP)] were also investigated. The study analysed data on 7,208 children, 12 yr of age, from the Brazilian Oral Health Survey (SBBrasil Project). Cluster analysis based on the observed/expected (O/E) ratios identified six significant clusters of oral clinical conditions: (i) dental caries and missing teeth; (ii) dental caries and dental trauma; (iii) dental trauma and gingivitis; (iv) dental caries, missing teeth, and dental trauma; (v) dental caries, dental trauma, and gingivitis; and (vi) all oral clinical conditions. Ordinal regression showed that poor social position was associated with a large number of oral clinical conditions. Poisson regression demonstrated that low social position and greater number of oral clinical conditions increased the likelihood of poor OHRQoL (Child-OIDP extent). The four oral clinical conditions clustered into six distinct clusters among Brazilian children. Multimorbidity of oral clinical conditions predicted poor OHRQoL. Social position was of high relevance to multimorbidity of oral clinical conditions and children's OHRQoL

    A virtual assistant architecture to support the delivery of texts in languages teaching - learning processes

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    Este artículo presenta la arquitectura de un Asistente virtual que ofrece funciones de apoyo al usuario en el proceso de producción de textos para la enseñanza y el aprendizaje de idiomas. Se definen dos funciones específicas para el comportamiento del asistente: la asistencia de escritura y la asistencia gramatical. En la asistencia de escritura se le presenta al estudiante recomendaciones de acuerdo al tipo de párrafo que desea escribir, y en la asistencia gramatical se le brinda al estudiante la corrección ortográfica y sintáctica de oraciones de los párrafos o textos que produce. El asistente integra características de agentes de software, ambientes virtuales de aprendizaje y elementos de la lingüística computacional que permiten realizar el procesamiento del lenguaje y dar recomendaciones a los estudiantes sobre su proceso de escritura. El principal propósito de este asistente es ayudar a los estudiantes a mejorar sus habilidades de escritura cuando interactúen en un entorno de aprendizaje virtual. La arquitectura propuesta se ha implementado en la plataforma denominada Lingweb, prototipo de un Sistema de Gestión de Cursos para la enseñanza y aprendizaje de idiomas. Abstract This paper presents the architecture of a Virtual Assistant that supports the delivery of texts in languages teaching–learning processes. Two specific functions for the assistant are defined: writing and grammatical assistance. On one hand, writing assistance provides students recommendations about the type of paragraph that they want to write. And, on the other hand, grammatical assistance provides students a feedback about their mistakes in the texts that they produce. The assistant has features related with three technological elements: i) software agents, ii) virtual learning environments and iii) computational linguistics. These features allow to provide the functionalities for language processing and they provide students’ recommendations about their writing processes. The main purpose of this assistant is to help the students to improve their writing skills, when they interact into a virtual learning environment. The proposed architecture was implemented in a platform called Lingweb, wich is a prototype of a Course Management System for the languages teaching-learning processes

    Dermatosis autoinmunes en caninos. Estudio retrospectivo

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    A retrospective study of canine skin samples diagnosed with autoimmune disease, admitted by the Veterinary Special Pathology Laboratory, was conducted between 2004 and 2016. Purposes of the study were to identify canine cases of skin lesions and to select those with a diagnosis of autoimmune disease. Autoimmune skin diseases were related to race, age, sex, type and anatomical location of the clinical lesions and, finally, different histopathological lesions characterizing each disease. Autoimmune diseases accounted for 2.07% of the total number of cases admitted in the study period, the most frequent being pemphigus foliaceus and discoid lupus erythematosus. The purebred dogs were more affected than the mixed animals, being the anatomical location of greater presentation the dorsal region of the nose (35.3%). Among the most frequent histopathological findings were pustules (54.1%), areas of dermo-epidermal separation (45.9%) and spongiosis (44.7%). Although the percentage of canines with autoimmune dermatosis is low, it is important to include differential diagnoses of the diseases that occur with pustules, papules, vesicles and inflammatory infiltrate in the dermoepidermal junction. Histopathology is a useful and accessible tool in that allows to diagnose these diseases.Se investigaron muestras de piel de caninos con diagnóstico de enfermedad autoinmune ingresadas entre los años 2004 y 2016 al Laboratorio de Patología Especial Veterinaria (FCV, La Plata, Argentina). Los objetivos fueron identificar casos de caninos con lesiones cutáneas y seleccionar aquéllos con diagnóstico de enfermedad autoinmune. También se propuso relacionar las dermatosis autoinmunes con la raza, edad, sexo, el tipo y la ubicación anatómica de las lesiones clínicas y, por ultimo, describir las diferentes lesiones histopatológicas que caracterizaron cada afección. Las enfermedades autoinmunes representaron el 2,07% del total de casos ingresados en el período de estudio, siendo las más frecuentes el pénfigo foliáceo y el lupus eritematoso discoide. Los caninos de raza pura fueron más afectados que los mestizos, siendo la región dorsal de la nariz la ubicación anatómica de mayor presentación (35,3%). Entre los hallazgos histopatológicos más reiterados se observaron pústulas (54,1%), áreas de separación dermoepidérmica (45,9%) y espongiosis (44,7%). Si bien el porcentaje de caninos con dermatosis autoinmunes es bajo, es importante incluirlas dentro de los diagnósticos diferenciales de las enfermedades que cursan con pústulas, pápulas, vesículas e infiltrado inflamatorio en la unión dermoepidérmica. La histopatología es una herramienta útil y relativamente accesible en nuestro medio, que permite arribar al diagnóstico de tales enfermedades
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