Geometric morphometric analyses provide evidence for the adaptive character of the Tanganyikan cichlid fish radiations.

The cichlids of East Africa are renowned as one of the most spectacular examples of adaptive radiation. They provide a unique opportunity to investigate the relationships between ecology, morphological diversity, and phylogeny in producing such remarkable diversity. Nevertheless, the parameters of the adaptive radiations of these fish have not been satisfactorily quantified yet. Lake Tanganyika possesses all of the major lineages of East African cichlid fish, so by using geometric morphometrics and comparative analyses of ecology and morphology, in an explicitly phylogenetic context, we quantify the role of ecology in driving adaptive speciation. We used geometric morphometric methods to describe the body shape of over 1000 specimens of East African cichlid fish, with a focus on the Lake Tanganyika species assemblage, which is composed of more than 200 endemic species. The main differences in shape concern the length of the whole body and the relative sizes of the head and caudal peduncle. We investigated the influence of phylogeny on similarity of shape using both distance-based and variance partitioning methods, finding that phylogenetic inertia exerts little influence on overall body shape. Therefore, we quantified the relative effect of major ecological traits on shape using phylogenetic generalized least squares and disparity analyses. These analyses conclude that body shape is most strongly predicted by feeding preferences (i.e., trophic niches) and the water depths at which species occur. Furthermore, the morphological disparity within tribes indicates that even though the morphological diversification associated with explosive speciation has happened in only a few tribes of the Tanganyikan assemblage, the potential to evolve diverse morphologies exists in all tribes. Quantitative data support the existence of extensive parallelism in several independent adaptive radiations in Lake Tanganyika. Notably, Tanganyikan mouthbrooders belonging to the C-lineage and the substrate spawning Lamprologini have evolved a multitude of different shapes from elongated and Lamprologus-like hypothetical ancestors. Together, these data demonstrate strong support for the adaptive character of East African cichlid radiations.

Disordered eating behaviors: what about boys?

PURPOSE: To determine the characteristics specific to boys with disordered eating behaviors (DEB) and the general context in which these DEB occur. METHOD: Data were drawn from the SMASH02 database, a survey carried out among post-mandatory school students in Switzerland aged 16-20 years in 2002. Only males (N=3890) were included, and were classified into into one of four groups based on their level of concern about weight/food and on their eating behaviors, as follows: group 1: one concern without behavior (N=862); group 2: more than one concern without behavior (N=361); group 3: at least one behavior (N=798); and a control group (N=1869), according to previously validated items. Groups were compared for personal, family, school, experience of violence, and health-compromising behaviors variables on the bivariate level. All significant variables were included in a multinomial logistic regression using Stata 9 software. RESULTS: About one-half of the boys reported either a concern or unhealthy eating behavior. Compared with the control group, boys from the three groups were more likely to be students and to report a history of sexual abuse, delinquency, depression, and feeling fat. In addition, boys from group 3 were more likely to report a history of dieting, early puberty, peer teasing, having experienced violence, frequent inebriation, and being overweight. CONCLUSION: DEB concern adolescent males more frequently than thought and seem to be integrated in a general dysfunctional context, in which violence is predominant. Adolescent males also need to be screened for DEB. Moreover, prevention programs should target the increasing social and media pressure regarding boys ideal body shape and raise public consciousness about this phenomenon.

Influencia de los medios de comunicación y de los grupos sociales en la percepción de la imagen corporal en pacientes con anorexia neviosa

La anorexia nerviosa es un trastorno de la conducta alimentaria que se caracteriza por unapérdida de peso superior al saludablemente recomendado, conductas para perder peso y evitarel aumento de peso, miedo a la obesidad y distorsión de la imagen corporal. Tanto la incidenciacomo la prevalencia de este tipo de trastornos ha aumentado considerablemente en las últimasdécadas, son varios los estudios que afirman que hay una estrecha relación entre la influencia delos factores socioculturales y el grado de distorsión de la imagen corporal en este tipo depacientes.El objetivo de este estudio es analizar la influencia que ejercen los medios de comunicación ylos grupos sociales en la distorsión de la imagen corporal de pacientes con anorexia nerviosa.Para lograr este objetivo se realizará un estudio fenomenológico con pacientes de 16 a 21 añosque se visiten en un hospital de día de trastornos de la conducta alimentaria. Los datos serecogerán mediante de una entrevista semiestructurada basada en los ítems del cuestionario deinfluencia de los modelos estéticos corporales (CIMEC). El análisis de los datos obtenidos serápor edición, transcribiendo la entrevista, identificando los segmentos significativos paraposteriormente poderlos analizar.En relación con las consideraciones finales, es un estudio que dentro de la subjetividad podríaser realmente útil para conocer desde el punto de vista del paciente cómo influyen los medios decomunicación y las relaciones sociales en la anorexia nerviosa, permitiendo la propuesta deacciones futuras que ayuden a estos adolescentes y adultos jóvenes a hacer frente a la presiónque ejerce la sociedad.

Evidence for morphological and adaptive genetic divergence between lake and stream habitats in European minnows (Phoxinus phoxinus, Cyprinidae).

Natural selection drives local adaptation, potentially even at small temporal and spatial scales. As a result, adaptive genetic and phenotypic divergence can occur among populations living in different habitats. We investigated patterns of differentiation between contrasting lake and stream habitats in the cyprinid fish European minnow (Phoxinus phoxinus) at both the morphological and genomic levels using geometric morphometrics and AFLP markers, respectively. We also used a spatial correlative approach to identify AFLP loci associated with environmental variables representing potential selective forces responsible for adaptation to divergent habitats. Our results identified different morphologies between lakes and streams, with lake fish presenting a deeper body and caudal peduncle compared to stream fish. Body shape variation conformed to a priori predictions concerning biomechanics and swimming performance in lakes vs. streams. Moreover, morphological differentiation was found to be associated with several environmental variables, which could impose selection on body and caudal peduncle shape. We found adaptive genetic divergence between these contrasting habitats in the form of 'outlier' loci (2.9%) whose genetic divergence exceeded neutral expectations. We also detected additional loci (6.6%) not associated with habitat type (lake vs. stream), but contributing to genetic divergence between populations. Specific environmental variables related to trophic dynamics, landscape topography and geography were associated with several neutral and outlier loci. These results provide new insights into the morphological divergence and genetic basis of adaptation to differentiated habitats.

Nuclear Matrix in Apoptotic Cell Death and Cell Proliferation. The role of Nuclear Mitotic Apparatus (NuMA) Protein

The nucleus is a membrane enclosed organelle containing most of the genetic information of the cell in the form of chromatin. The nucleus, which can be divided into many sub-organelles such as the nucleoli, the Cajal bodies and the nuclear lamina, is the site for several essential cellular functions such as the DNA replication and its regulation and most of the RNA synthesis and processing. The nucleus is often affected in disease: the size and the shape of the nucleus, the chromatin distribution and the size of the nucleoli have remained the basis for the grading of several cancers. The maintenance of the vertebrate body shape depends on the skeleton. Similarly, in a smaller context, the shape of the cell and the nucleus are mainly regulated by the cytoskeletal and nucleoskeletal elements. The nuclear matrix, which by definition is a detergent, DNase and salt resistant proteinaceous nuclear structure, has been suggested to form the nucleoskeleton responsible for the nuclear integrity. Nuclear mitotic apparatus protein, NuMA, a component of the nuclear matrix, is better known for its mitotic spindle organizing function. NuMA is one of the nuclear matrix proteins suggested to participate in the maintenance of the nuclear integrity during interphase but its interphase function has not been solved to date. This thesis study concentrated on the role of NuMA and the nuclear matrix as structural and functional components of the interphase nucleus. The first two studies clarified the essential role of caspase-3 in the disintegration of the nuclear structures during apoptosis. The second study also showed NuMA and chromatin to co-elute from cells in significant amounts and the apoptotic cleavage of NuMA was clarified to have an important role in the dissociation of NuMA from the chromatin. The third study concentrated on the interphase function of NuMA showing NuMA depletion to result in cell cycle arrest and the cytoplasmic relocalization of NuMA interaction partner GAS41. We suggest that the relocalization of the transcription factor GAS41 may mediate the cell cycle arrest. Thus, this study has given new aspects in the interactions of NuMA, chromatin and the nuclear matrix.

Spatial and temporal variation in fish populations and assemblages in coastal waters of the northern Baltic Proper

The distribution and traits of fish are of interest both ecologically and socio-economically. In this thesis, phenotypic and structural variation in fish populations and assemblages was studied on multiple spatial and temporal scales in shallow coastal areas in the archipelago of the northern Baltic Proper. In Lumparn basin in Åland Islands, the fish assemblage displayed significant seasonal variation in depth zone distribution. The results indicate that investigating both spatial and temporal variation in small scale is crucial for understanding patterns in fish distribution and community structure in large scale. The local population of Eurasian perch Perca fluviatilis L displayed habitat-specific morphological and dietary variation. Perch in the pelagic zone were on average deeper in their body shape than the littoral ones and fed on fish and benthic invertebrates. The results differ from previous studies conducted in freshwater habitats, where the pelagic perch typically are streamlined in body shape and zooplanktivorous. Stable isotopes of carbon and nitrogen differed between perch with different stomach contents, suggesting differentiation of individual diet preferences. In the study areas Lumparn and Ivarskärsfjärden in Åland Islands and Galtfjärden in Swedish east coast, the development in fish assemblages during the 2000’s indicated a general shift towards higher abundances of small-bodied lower-order consumers, especially cyprinids. For European pikeperch Sander lucioperca L., recent declines in adult fish abundances and high mortalities (Z = 1.06–1.16) were observed, which suggests unsustainably high fishing pressure on pikeperch. Based on the results it can be hypothesized that fishing has reduced the abundances of large predatory fish, which together with bottom-up forcing by eutrophication has allowed the lower-order consumer species to increase in abundances. This thesis contributes to the scientific understanding of aquatic ecosystems with new descriptions on morphological and dietary adaptations in perch in brackish water, and on the seasonal variation in small-scale spatial fish distribution. The results also demonstrate anthropogenic effects on coastal fish communities and underline the urgency of further reducing nutrient inputs and regulating fisheries in the Baltic Sea region.

Le rôle d’une insatisfaction corporelle dans l’adoption de pratiques de maintien et de changement du poids chez des adolescents québécois

L’objectif de recherche principal poursuivi dans cette thèse de doctorat est de mieux comprendre le rôle d’une insatisfaction corporelle dans l’adoption de pratiques de maintien et de changement du poids chez des adolescent(e)s québécois(es). Pour atteindre cet objectif de recherche principal, trois articles scientifiques liés les uns aux autres ont été rédigés. Chaque article poursuit des objectifs spécifiques (1er article: estimer les proportions d’adolescent(e)s québécois(e)s poursuivant un objectif de poids apparié et non-apparié à leur poids actuel et identifier les déterminants des objectifs de poids non-apparié au poids actuel, 2e article: identifier des associations entre un objectif de poids apparié vs. non-apparié au poids actuel et la fréquence d’utilisation de différents comportements liés au poids et à l’alimentation, 3e article: observer des associations entre différents degrés d’insatisfaction corporelle et l’utilisation de divers comportements liés au poids et à l’alimentation et examiner le rôle modérateur d’un objectif de poids apparié vs. non-apparié au poids actuel dans ces associations) permettant de répondre à l’objectif de recherche principal. Ces articles ont tous été élaborés à partir de l’analyse secondaire d’une banque de données quantitatives constituée par l’Institut de la statistique du Québec (ISQ) et nommée: Enquête sociale et de santé auprès des enfants et des adolescents québécois (ESSEA). L’ESSEA a été constitué auprès d’un échantillon populationnel et représentatif d’enfants et d’adolescent(e)s québécois(es) âgé(e)s de neuf, 13 et 16 ans. Les résultats de cette thèse indiquent qu’une insatisfaction corporelle est associée à la poursuite d’un objectif de poids non-apparié au poids actuel, ainsi qu’à l’utilisation de comportements liés au poids et à l’alimentation sains, malsains et déviants. Des associations ont également été observées entre l’objectif de poids poursuivi par un adolescent(e) et divers comportements utilisés pour l’atteindre. En effet, la poursuite d’un objectif de poids non-apparié au poids actuel est associée à l’utilisation de comportements malsains. Cette association n’est cependant pas présente en ce qui à trait à l’utilisation de comportements sains et déviants, ceux-ci étant strictement prédits par une insatisfaction corporelle. Des effets de médiation et de modération ont aussi été identifiés. Une insatisfaction corporelle est une variable de médiation entre une détresse psychologique chez les adolescentes et la poursuite d’un objectif de poids non-apparié au poids actuel. Finalement, un objectif de poids non-apparié au poids actuel est une variable modifiant l’association entre une insatisfaction corporelle et l’utilisation de comportements malsains chez les adolescent(e)s québécois(es). En conclusion, il existe diverses associations entre une insatisfaction corporelle et l’adoption de pratiques de maintien et de changement du poids chez des adolescent(e)s québécois(es). Une insatisfaction corporelle est donc une cible d’intervention pertinente pour la santé publique puisqu’elle peut servir de base à l’élaboration d’interventions visant la promotion d’un poids santé ainsi que de saines stratégies de contrôle du poids.

Activité physique et insatisfaction de l'image corporelle chez un groupe d'adolescentes

Essai doctoral présenté à la Faculté des études supérieures en vue de l’obtention du grade de Docteur en psychologie (D.Psy.), option clinique

Attitudes et comportements alimentaires des athlètes québécoises pratiquant un sport esthétique à un haut niveau : caractéristiques personnelles et comparaison à un groupe de contrôle

La pratique d’un sport de type esthétique est aujourd’hui considérée par plusieurs (Sundgot-Borgen & Torstveit, 2004; Thompson & Sherman, 2010) comme un facteur de risque à l’adoption d’attitudes et de comportements alimentaires inappropriés à l’égard de l’alimentation et de l’image corporelle (ACIAI) et ultimement au développement d’un trouble des conduites alimentaires (TCA). Les études actuelles portant sur cette problématique rapportent toutefois des résultats contradictoires. De plus, certains aspects méthodologiques associés notamment à l’hétérogénéité des échantillons limitent la portée interprétative de ces résultats. Afin de pallier les limites actuelles des écrits empiriques, cette thèse a pour but de tracer le portrait de la problématique des désordres alimentaires chez les jeunes athlètes québécoises de haut niveau en sport esthétique. Pour ce faire, un échantillon homogène de 145 adolescentes âgées de 12 à 19 ans a été constitué soit 52 athlètes de haut niveau et 93 non-athlètes. Les sports représentés sont le patinage artistique, la nage synchronisée et le ballet. À partir de cet échantillon, deux études sont réalisées. L’objectif de la première étude est de comparer l’intensité des ACIAI et la prévalence des TCA dans les deux groupes à l’aide de deux questionnaires soit le Eating Disorder Examination Questionnaire (EDE-Q) et le Eating Disorder Inventory-3 (EDI-3). Les résultats obtenus suggèrent qu’il n’y a pas de différence significative entre les athlètes et les non-athlètes de l’échantillon en ce qui a trait à l’intensité des ACIAI et à la prévalence des TCA. La deuxième étude est constituée de deux objectifs. Tout d’abord, comparer les deux groupes relativement aux caractéristiques personnelles suivantes : l’insatisfaction de l’image corporelle (IIC), le sentiment d’efficacité personnelle envers l’alimentation normative (SEP-AN) et l’image corporelle (SEP-IC), le perfectionnisme (P), l’ascétisme (As), la dysrégulation émotionnelle (DÉ) et le déficit intéroceptif (DI). De nature plus exploratoire, le second objectif de cette étude est de décrire et de comparer les caractéristiques personnelles qui sont associées aux ACIAI dans chacun des groupes. Afin de réaliser ces objectifs, deux autres questionnaires ont été utilisés soit le Eating Disorder Recovery Self-efficacy Questionnaire-f (EDRSQ-f) et le Body Shape Questionnaire (BSQ). En somme, les analyses indiquent que les athlètes de l’échantillon présentent des niveaux plus faibles de SEP-AN et de DÉ. Ce faisant, elles auraient moins confiance en leur capacité à maintenir une alimentation normative, mais réguleraient plus efficacement leurs émotions que les adolescentes non-athlètes. Une fois l’âge et l’indice de masse corporelle contrôlés, les résultats démontrent également que le SEP-AN et l’IIC contribuent à prédire dans chaque groupe les ACIAI tels que mesurés par la recherche de minceur. Le SEP-AN a aussi été associé dans les deux groupes à l’intensité des symptômes boulimiques. Les modèles obtenus diffèrent cependant quant aux variables prédictives principales. Chez les athlètes de l’échantillon, l’intensité des conduites boulimiques est associée à la DÉ alors qu’elle est davantage liée au DI chez les adolescentes non sportives. Enfin, en plus de discuter et de comparer l’ensemble de ces résultats aux autres travaux disponibles, les apports distinctifs de la thèse et les principales limites des études sont abordés. Des pistes sont également suggérées afin d’orienter les recherches futures et des implications cliniques sont proposées.

Insatisfacci??n corporal en adolescentes latinoamericanas y espa??olas

Resumen tomado de la publicaci??n

Diseño, construcción y validación de una escala de insatisfacción corporal para adolescentes.

Diseñar una escala de Insatisfacción Corporal para Adolescentes, con los correspondientes estudios de fiabilidad y validez, con objeto de paliar en parte la escasez de técnicas de evaluación de imagen corporal en España. 569 sujetos, chicos y chicas de entre 12 a 19 años escolarizados en dos Institutos de Educación Secundaria de Navarra. Siguiendo el modelo básico de construcción de Test y de diseño de Escalas de Actitudes tipo Likert, adaptando a las características de este trabajo concreto, así como a las limitaciones prácticas que se fueron presentando, el proceso se realizó a través de seis estudios: I.-Determinación rasgo-técnica y selección inicial de ítems. II.-Depuración de ítems por jueces. III.-Asignación de valores a los ítems y análisis del poder discriminante de los ítems. IV.-Estudios de fiabilidad. V.-Estudios de validez. VI.-Valores de referencia y tipificación. I.-Body Shape Questionnarie (Cuestionario de la Forma/Figura Corporal ): es un cuestionario específico para la evaluación de insatisfacción corporal. Se ha utilizado como instrumento de evaluación de imagen corporal y para validación de otros. Está compuesta por 34 ítems y ha obtenido buenos niveles de fiabilidad y validez concurrente en diversas investigaciones. II.-Subescala IC del Eating Disorder Inventory ( Inventario de Conductas Alimentarias Alteradas ): el objetivo es la evaluación de los síntomas que acompaña a los TCA ( Anorexia y Bulimia Nerviosa ), aunque se ha extendido su uso en el ámbito de la investigación con población no patológica. En su segunda versión está compuesta por 91 ítems y 11 escalas. III.-Eating Attitudes Test-40 ( Test de Actitudes hacia la Conducta Alimentaria ): es el instrumento de medida estandarizado más utilizado en la evaluación de situación de riesgo para sufrir un TCA y de sintomatología específica en muestras clínicas. I.-Se ha diseñado una escala de evaluación de insatisfacción corporal en adolescentes- escala tipo Likert - compuesta por 35 ítems. La escala se denomina Escala de Evaluación de Insatisfacción Corporal en Adolescentes ( EEICA ). II.-Analizando los valores de consistencia interna, fiabilidad test-retest y fiabilidad dos mitades, y comparando los resultados con diversos instrumentos de evaluación de imagen corporal, se puede considerar como una escala con buena fiabilidad y por consiguiente alta consistencia interna. En España existen 3 instrumentos propios para evaluar la imagen corporal, o la insatisfacción corporal de forma específica, ( en el mundo anglosajón, existen más de 100 ). Teniendo en cuenta dicha información, disponer de una escala específica, diseñada con población adolescente española y con juicio de especialistas españoles, supone una aportación novedosa al panorama de la evaluación de la imagen corporal en España. Dicha escala obtiene referentes psicométricos similares a los que se han conseguido con otras escalas diseñadas con el mismo.

Incidencia de un programa de Educación Física en la percepción de la propia imagen corporal.

Resumen basado en el de la publicación

Atividade física, discriminação e preocupação com a forma corporal em obesos submetidos a cirurgia bariátrica

A obesidade acarreta consequências ao nível da diminuição de saúde mas também a nível social, sendo os obesos vítimas de elevada discriminação devido ao seu peso. O objetivo principal deste trabalho é analisar a associação entre a atividade física e a perceção de discriminação em obesos submetidos a cirurgia bariátrica. O objetivo secundário prende-se com o estudo da associação entre a atividade física e a preocupação com forma corporal. O trabalho está dividido em duas partes distintas, sendo a primeiro dedicada à revisão sistemática da literatura que abordou os temas da discriminação, insatisfação corporal e atividade física nos obesos. Desta revisão concluí-se que a discriminação e insatisfação com forma corporal contribuem para a manutenção de comportamentos sedentários, no entanto com a prática de atividade física estas tendem a diminuir. A segunda parte do trabalho consiste num estudo observacional retrospetivo, constituído por uma amostra de 98 sujeitos com obesidade mórbida que tenham realizado uma cirurgia bariátrica, com idades compreendidas entre os 26 e os 73 anos. Com recurso à aplicação de questionários avaliou-se a atividade física e a sua associação com a discriminação e preocupação com forma corporal. Os resultados obtidos indicam que a discriminação não se encontra associada à atividade física nem ao IMC. Verificou-se que a atividade física de intensidade moderada e vigorosa está associada à diminuição da preocupação com forma corporal. A preocupação com forma corporal está também associada ao IMC. A atividade física deve ser integrada no programa multidisciplinar que acompanha a cirurgia.

Intergenerational effects of birth weight on glucose tolerance and reproductive performance

Women who were themselves small-for-gestational age (SGA) are at a greater risk of adulthood diseases such as non-insulin-dependent diabetes mellitus (NIDDM), and twice at risk of having an SGA baby themselves. The aim of this study was to examine the intergenerational pig. Low (L) and normal (N) birth weight female piglets were followed throughout their first pregnancy (generation 1 (0)). After they had given birth, the growth and development of the lightest (I) and heaviest (n) female piglet from each litter were monitored until approximately 5 months of age (generation 2 (G2)). A glucose tolerance test (GTT) was conducted on G1 pig at similar to 6 months of age and again during late pregnancy; a GTT was also conducted on G2 pigs at similar to 4 months of age. G1 L offspring exhibited impaired glucose metabolism in later life compared to their G1 N sibling but in the next generation a similar scenario was only observed between I and n offspring born to G1 L mothers. Despite G1 L mothers showing greater glucose intolerance in late pregnancy and a decreased litter size, average piglet birth weight was reduced and there was also a large variation in litter weight; this suggests that they were, to some extent, prioritising their nutrient intake towards themselves rather than promoting their reproductive performance. There were numerous relationships between body shape at birth and glucose curve characteristics in later life, which can, to some extent, be used to predict neonatal outcome. In conclusion, intergenerational effects are partly seen in the pig. It is likely that some of the intergenerational influences may be masked due to the pig being a litter-bearing species.

Children's representation of family mealtime in the context of maternal eating disorders

Background Recent research provides evidence for specific disturbance in feeding and growth in children of mothers with eating disorders. Aim To investigate the impact of maternal eating disorders during the post-natal year on the internal world of children, as expressed in children's representations of self and their mother in pretend mealtime play at 5 years of age. Methods Children of mothers with eating disorders (n = 33) and a comparison group (n = 24) were videotaped enacting a family mealtime in pretend play. Specific classes of children's play representations were coded blind to group membership. Univariate analyses compared the groups on representations of mother and self. Logistic regression explored factors predicting pretend play representations. Results Positive representations of the mother expressed as feeding, eating or body shape themes were more frequent in the index group. There were no other significant group differences in representations. In a logistic regression analysis, current maternal eating psychopathology was the principal predictor of these positive maternal representations. Marital criticism was associated with negative representations of the mother. Conclusions These findings suggest that maternal eating disorders may influence the development of a child's internal world, such that they are more preoccupied with maternal eating concerns. However, more extensive research on larger samples is required to replicate these preliminary findings.