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SUMMARY: Adipose tissue morphology of different fat tissue depots can be described using the number of adipocytes and cell surface of adipocytes. This study deals with characteristics and morphometric analysis of white and brown adipose tissue depots in healthy adult laboratory mice, hamsters and rats of both sexes. The number of unilocular adipocytes in white adipose tissue differs from one adipose tissue depot to another, with the largest number of adipocytes in mice and a similar number in hamsters and rats. The smallest surface area and the largest percentage of small unilocular adipocytes were found in mice. White adipose tissue in hamsters and rats was predominantly made out of a larger percentage of medium-sized adipocytes and a smaller percentage of small and medium-sized adipocytes. Uncoupling protein 1 positive multilocular adipocytes were found in classic brown adipose tissue depots with larger percentages in mice (93.20 %) and hamsters (91.30 %), while rats had a smaller percentage (78.10 %). In white and brown adipose tissue, significant differences between species and both sexes within the same species were found, indicating the influence of sexual dimorphism. The presented morphometric results could serve as a basis for further studies concerning experimental animal models of metabolic disorders and obesity.

RESUMEN: La morfología del tejido adiposo de diferentes depósitos de tejido graso se puede describir utilizando el número de adipocitos y la superficie celular de los adipocitos. Este estudio analiza las características y el análisis morfométrico de los depósitos de tejido adiposo blanco y marrón en ratones, hamsters y ratas de laboratorio, adultos sanos de ambos sexos. El número de adipocitos uniloculares en el tejido adiposo blanco difiere de un depósito de tejido adiposo a otro, con el mayor número de adipocitos en ratones y un número similar en hámsteres y ratas. La superficie más pequeña y el mayor porcentaje de adipocitos uniloculares pequeños se encontraron en ratones. El tejido adiposo blanco en hámsteres y ratas estaba compuesto predominantemente por un mayor porcentaje de adipocitos de tamaño mediano y un porcentaje menor de adipocitos de tamaño pequeño y mediano. Los adipocitos multiloculares positivos para la proteína desacopladora 1 se encontraron en depósitos de tejido adiposo marrón clásico con mayores porcentajes en ratones (93,20 %) y hámsters (91,30 %), mientras que las ratas tenían un porcentaje menor (78,10 %). En el tejido adiposo blanco y pardo se encontraron diferencias significativas entre especies y entre ambos sexos dentro de una misma especie, lo que indica la influencia del dimorfismo sexual. Los resultados morfométricos presentados podrían servir como base para futuros estudios sobre modelos animales experimentales de trastornos metabólicos y obesidad.

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In view of the scarcity of data about the topography and syntopy of abdominopelvic viscera of the giant anteater (Myrmecophage tridactyla - Linnaeus, 1758), the present study aimed to elucidate these characteristics and to compare them with the other animal species, especially the domestic ones. Three specimens, two males and one female, were donated by the Environmental Military Police of Franca to the Anatomy Veterinary Laboratory of the University of Franca, after death by road killings. The animals were fixed and maintained in aqueous 10% formaldehyde solution, followed by conventional dissection of the abdominopelvic cavities for subsequent direct inspection and topographic description of the viscera, aiming at comparative analyzes with other species, whose positioning and particularities are already established in the literature. It was observed that most of the viscera of these cavities have similar location and syntopy to domestic animals, except for the kidneys and testicles. In view of the established methodology and the results obtained, it is accepted that more specimens of anteater, both genera, should be evaluated and registered scientifically to confirm the data of the current research and anatomical preconization of the abdominopelvic cavity, inasmuch anatomical individual variation are possible between animals of the same species.(AU)

Diante da escassez de dados sobre a topografia e a sintopia das vísceras abdominopélvicas do tamanduá-bandeira (Myrmecophage tridactyla - Linnaeus, 1758), o presente estudo teve como objetivo elucidar essas características e compará-las com as demais espécies animais, mormente as domésticas. Utilizaram-se três espécimes, dois machos e uma fêmea, provenientes de doação da Polícia Militar Ambiental de Franca ao Laboratório de Anatomia Veterinária da Universidade de Franca, após óbitos por atropelamentos. Os animais foram fixados e mantidos em solução aquosa de formaldeído a 10%, seguidos de dissecação convencional das cavidades abdominopélvicas para posterior inspeção direta e descrição topográfica das vísceras, visando a análises comparativas com outras espécies, cujo posicionamento e cujas particularidades já são bem estabelecidos na literatura. Observou-se que a maioria das vísceras dessas cavidades possuem localização e sintopia similares aos animais domésticos, exceto os rins e os testículos. Diante da metodologia estabelecida e dos resultados obtidos, admite-se que mais espécimes de tamanduás-bandeiras, de ambos os gêneros, devam ser avaliados e registrados cientificamente, visando à confirmação dos dados da atual pesquisa e à preconização anatômica da cavidade abdominopélvica, visto que variações anatômicas individuais são passíveis entre animais da mesma espécie.(AU)

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In view of the scarcity of data about the topography and syntopy of abdominopelvic viscera of the giant anteater (Myrmecophage tridactyla - Linnaeus, 1758), the present study aimed to elucidate these characteristics and to compare them with the other animal species, especially the domestic ones. Three specimens, two males and one female, were donated by the Environmental Military Police of Franca to the Anatomy Veterinary Laboratory of the University of Franca, after death by road killings. The animals were fixed and maintained in aqueous 10% formaldehyde solution, followed by conventional dissection of the abdominopelvic cavities for subsequent direct inspection and topographic description of the viscera, aiming at comparative analyzes with other species, whose positioning and particularities are already established in the literature. It was observed that most of the viscera of these cavities have similar location and syntopy to domestic animals, except for the kidneys and testicles. In view of the established methodology and the results obtained, it is accepted that more specimens of anteater, both genera, should be evaluated and registered scientifically to confirm the data of the current research and anatomical preconization of the abdominopelvic cavity, inasmuch anatomical individual variation are possible between animals of the same species.(AU)

Diante da escassez de dados sobre a topografia e a sintopia das vísceras abdominopélvicas do tamanduá-bandeira (Myrmecophage tridactyla - Linnaeus, 1758), o presente estudo teve como objetivo elucidar essas características e compará-las com as demais espécies animais, mormente as domésticas. Utilizaram-se três espécimes, dois machos e uma fêmea, provenientes de doação da Polícia Militar Ambiental de Franca ao Laboratório de Anatomia Veterinária da Universidade de Franca, após óbitos por atropelamentos. Os animais foram fixados e mantidos em solução aquosa de formaldeído a 10%, seguidos de dissecação convencional das cavidades abdominopélvicas para posterior inspeção direta e descrição topográfica das vísceras, visando a análises comparativas com outras espécies, cujo posicionamento e cujas particularidades já são bem estabelecidos na literatura. Observou-se que a maioria das vísceras dessas cavidades possuem localização e sintopia similares aos animais domésticos, exceto os rins e os testículos. Diante da metodologia estabelecida e dos resultados obtidos, admite-se que mais espécimes de tamanduás-bandeiras, de ambos os gêneros, devam ser avaliados e registrados cientificamente, visando à confirmação dos dados da atual pesquisa e à preconização anatômica da cavidade abdominopélvica, visto que variações anatômicas individuais são passíveis entre animais da mesma espécie.(AU)

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OBJETIVO: Apresentar um método prático de ensino e avaliar o grau de eficácia do aprendizado, comparando alunos que passaram pelo curso durante a graduação básica (sétimo semestre) e após 18 meses (décimo semestre), já no internato hospitalar. MÉTODOS: As vísceras conservadas por refrigeração, com coração, estruturas vasculares do mediastino, traqueia e pulmões, foram fixadas em suporte metálico apropriado. Os vasos supra- -aórticos foram ligados, e uma sonda de Foley foi introduzida retrogradamente para a infusão de água, permitindo a apresentação de procedimentos operatórios. Foram aplicados questionários a 40 alunos do sétimo e décimo semestre. As respostas foram submetidas à análise estatística. RESULTADOS: Foram demonstradas técnicas necessárias para o estabelecimento de circulação extracorpórea, confecção de enxerto aorta-coronária com segmento da artéria carótida obtido no mesmo bloco de vísceras, substituição da valva aórtica por prótese valvar sintética, correção de defeito previamente realizado no septo atrial, posicionamento dos vários tipos de eletrodos utilizados para a estimulação elétrica do coração, demonstração de técnicas empregadas para transplante cardíaco, simulação e correção de ferimentos do coração e da aorta. O grau de adequação da ferramenta avaliada foi positivo, com valores entre 55 e 95%, e houve retenção dos ensinamentos após 18 meses. Conclusão: Este método de ensino foi de fácil preparação e baixo custo, permitindo a realização de operações complexas e despertando interesse durante a graduação em Medicina.(AU)

OBJECTIVE: To present this practical teaching method, and assess the degree of learning effectiveness, comparing students who attended the course during basic undergraduation (seventh semester), and after eighteen months (tenth semester), when already in the Hospital internship. METHODS: Thoracic viscera, with heart, vascular structures of the mediastinum, trachea and lungs, preserved by refrigeration, were fixed in a metallic device. The supra-aortic branches were connected, and a Foley catheter was introduced backwards for water infusion, allowing the presentation of surgical procedures. Questionnaires were applied to 40 students of the seventh and tenth semesters; the answers underwent statistical analysis. RESULTS: The following techniques were demonstrated: establishment of cardiopulmonary bypass; coronary artery bypass grafting with carotid artery segment obtained in the same block of viscera; aortic valve replacement with synthetic valve; patch made with biological material in order to correct a defect previously held in the atrial septum; positioning of the various types of electrodes used for electrical stimulation of the heart; demonstration of techniques performed in cardiac transplantation and simulation and correction of both heart and aorta injuries. The degree of adequacy of such tool was positive, with values between 55 and 95%, and retention of what was taught after 18 months. CONCLUSION: This teaching method requires easy preparation and low cost, allowing the performance of complex operations, attracting medical students' interest.(AU)

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Se describe la relación de la anatomía con la aruspicina, también conocida como hieroscopia y extispicina. Se trata del método de adivinar, examinado las vísceras de un animal sacrificado e interpretando detalles de esta anatomía macroscópica con el fin de predecir el futuro, siempre ligado a una voluntad divina. Eran las antiguas civilizaciones las que practicaban este arte supersticioso de adivinar basados en la conformación anatómica que presentaban dichas vísceras. Por estas razones, es muy probable que estos individuos hayan desarrollado un notable conocimiento de la anatomía y que hayan utilizado una terminología anatómica propia que hoy desconocemos por falta de documentación.

The relation between anatomy with haruspicina (also called hieroscopia and extispicina) is described. This is the method to guess, examined the entrails of a slaughtered animal and interpreting details of this gross anatomy in order to predict the future, always linked to a divine will. Ancient civilizations were those who practiced this art to guess superstitious based on anatomical conformation presenting these viscera. For these reasons, it is likely that these individuals have developed considerable knowledge of anatomy and have their own anatomical terminology used today unknown for lack of documentation.

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Background: The study of the arterial vascularization of the abdominal cavity viscera is essential on the process of learning anatomy. For authors, various anatomical techniques can be used for the preservation of structures, allowing the exploration and visualization of the organs shape in many different ways. Among the techniques there is the angioarchitecture of viscera, with or without the utilization of formaldehyde. The aim of this paper is to describe a technique for anatomical preparation of the intestines (small and large) of dogs and cats using dried viscera and angioarchitecture, to facilitate the study and visualization of the cranial and caudal mesenteric arteries branching.Materials, Methods & Results: Twenty pieces of intestine of dogs and two of cats were used. The intestine was removed from the duodenum to the cranial portion of the rectum, the root of the mesentery was sectioned as well as the cranial and caudal mesenteric arteries. The part was washed, then the caudal and cranial mesenteric and pancreaticoduodenal arteries were ligated, latex was injected in the cranial mesenteric artery and the sample remained immersed in a 10% acetic acid aqueous solution. The cranial portion of the rectum was ligated and, through a cannula into the duodenum, air was insufflated until the viscera were distended. Following that, the part was positioned and fixed, exposed...(AU)

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Background: The study of the arterial vascularization of the abdominal cavity viscera is essential on the process of learning anatomy. For authors, various anatomical techniques can be used for the preservation of structures, allowing the exploration and visualization of the organs shape in many different ways. Among the techniques there is the angioarchitecture of viscera, with or without the utilization of formaldehyde. The aim of this paper is to describe a technique for anatomical preparation of the intestines (small and large) of dogs and cats using dried viscera and angioarchitecture, to facilitate the study and visualization of the cranial and caudal mesenteric arteries branching.Materials, Methods & Results: Twenty pieces of intestine of dogs and two of cats were used. The intestine was removed from the duodenum to the cranial portion of the rectum, the root of the mesentery was sectioned as well as the cranial and caudal mesenteric arteries. The part was washed, then the caudal and cranial mesenteric and pancreaticoduodenal arteries were ligated, latex was injected in the cranial mesenteric artery and the sample remained immersed in a 10% acetic acid aqueous solution. The cranial portion of the rectum was ligated and, through a cannula into the duodenum, air was insufflated until the viscera were distended. Following that, the part was positioned and fixed, exposed...

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Introducción: la gestión de las herramientas que proveen los espacios virtuales de enseñanza y aprendizaje (EVEA) son parte del proceso de enseñanza-aprendizaje. Los casos clínicos quirúrgicos (CQ) y clínico-imagenológicos (CI) potencian la abstracción conceptual y visuoespacial obtenida durante los trabajos prácticos (TO), focalizando parámetros anatómicos más signficativos. Objetivos: evaluar la gestión de recursos y rendimiento en casos clínico-quirúrgicos y clínico-imagenológicos en la rotación de Esplacnología mediante un EVEA, en función de sus características socioeconómicas. Material y métodos: estudio observacional y transversal mediante la utilización de un EVERA como recursos complementario a los prácticos de la rotación de esplacnología en 352 alumnos del año 2011 de la asignatura Anatomía. Valoramos parámetros de uso de los contenidos y de rendimiento en distintas actividades (casos CQ y CI) con especificación de las herramientas pedagógicas y virtuales utilizadas. Aplicamos pruebas estadísticas a los resultados. Resultados: los casos CQ registraron mayor promedio de ingresos/semana con mayor tiempo de logueo. La cantidad de horas trabajadas semanales fue proporcional al promedio de ingresos por semana al EVEA (R2=0.82) e inversamente proporcional al tiempo promedio de logueo (R2=0,84). En casos rendimiento en casos CI fue proporcional al resutlado en el examen parcial (R2=0.62) y los casos CQ fueron inversos a las horas trabajadas semanales (R2=0.77). Conclusiones: Determinamos características pedagógicas inherentes en los casos clínico-quirúrgicos y clínico-imagenológicos que influyeron en el uso, gestión de contenidos y rendiiento en el espacio virtual por parte de los alumnos. (AU)

Introduction: Managing the tools that provide teaching/learning virtual spaces (EVEA, in Spanish) is part of the teaching-learning process. Clinical-surgical (CS) and clinical-imaging (CI) cases promote the abstraction of concepts and visuospatial cognition acquired during practice assignments (PA), focusing on the most relevant anatomic parameters. Objectives: Assess the resources and achievement management in clinical-surgical and clinical-imaging in the Splanchnology medical rotation by means of an EVEA (teaching/learning virtual space), according to their socioeconomic characteristics.Material and methods: Observational and cross-sectional study using an EVEA as an additional resource for the assignments of the Splanchnology medical rotation in 352 Anatomy students, in 2011. We have assessed achievement and contents use parameters in different activities (CS and CI cases), specifying virtual and teaching tools used. We have applied statistical tests to the results.Results: CS cases registered a higher average of access/week, with longer login time. The number of hours worked per week was proportional to the EVEA (R2=0.82) and inversely proportional to the average login time (R2= 0.84). As regards the CI cases, a higher percentage of PA with a passing mark was registered (76.91%). Achievement in CI cases was proportional to the result obtained in the mid-term exam (R2=0.62) and CS cases were inversely proportional to the hours worked per week (R2= 0.77).Conclusions: We have determined the teaching characteristics attached to the clinical-surgical and clinical-imaging cases which have influenced the studentsÆ use, contents and achievement management in the virtual space. (AU)

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Introducción: la gestión de las herramientas que proveen los espacios virtuales de enseñanza y aprendizaje (EVEA) son parte del proceso de enseñanza-aprendizaje. Los casos clínicos quirúrgicos (CQ) y clínico-imagenológicos (CI) potencian la abstracción conceptual y visuoespacial obtenida durante los trabajos prácticos (TO), focalizando parámetros anatómicos más signficativos. Objetivos: evaluar la gestión de recursos y rendimiento en casos clínico-quirúrgicos y clínico-imagenológicos en la rotación de Esplacnología mediante un EVEA, en función de sus características socioeconómicas. Material y métodos: estudio observacional y transversal mediante la utilización de un EVERA como recursos complementario a los prácticos de la rotación de esplacnología en 352 alumnos del año 2011 de la asignatura Anatomía. Valoramos parámetros de uso de los contenidos y de rendimiento en distintas actividades (casos CQ y CI) con especificación de las herramientas pedagógicas y virtuales utilizadas. Aplicamos pruebas estadísticas a los resultados. Resultados: los casos CQ registraron mayor promedio de ingresos/semana con mayor tiempo de logueo. La cantidad de horas trabajadas semanales fue proporcional al promedio de ingresos por semana al EVEA (R2=0.82) e inversamente proporcional al tiempo promedio de logueo (R2=0,84). En casos rendimiento en casos CI fue proporcional al resutlado en el examen parcial (R2=0.62) y los casos CQ fueron inversos a las horas trabajadas semanales (R2=0.77). Conclusiones: Determinamos características pedagógicas inherentes en los casos clínico-quirúrgicos y clínico-imagenológicos que influyeron en el uso, gestión de contenidos y rendiiento en el espacio virtual por parte de los alumnos.

Introduction: Managing the tools that provide teaching/learning virtual spaces (EVEA, in Spanish) is part of the teaching-learning process. Clinical-surgical (CS) and clinical-imaging (CI) cases promote the abstraction of concepts and visuospatial cognition acquired during practice assignments (PA), focusing on the most relevant anatomic parameters. Objectives: Assess the resources and achievement management in clinical-surgical and clinical-imaging in the Splanchnology medical rotation by means of an EVEA (teaching/learning virtual space), according to their socioeconomic characteristics.Material and methods: Observational and cross-sectional study using an EVEA as an additional resource for the assignments of the Splanchnology medical rotation in 352 Anatomy students, in 2011. We have assessed achievement and contents use parameters in different activities (CS and CI cases), specifying virtual and teaching tools used. We have applied statistical tests to the results.Results: CS cases registered a higher average of access/week, with longer login time. The number of hours worked per week was proportional to the EVEA (R2=0.82) and inversely proportional to the average login time (R2= 0.84). As regards the CI cases, a higher percentage of PA with a passing mark was registered (76.91%). Achievement in CI cases was proportional to the result obtained in the mid-term exam (R2=0.62) and CS cases were inversely proportional to the hours worked per week (R2= 0.77).Conclusions: We have determined the teaching characteristics attached to the clinical-surgical and clinical-imaging cases which have influenced the students’ use, contents and achievement management in the virtual space.

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Amphibians share with other ectothermic vertebrates an extracutaneous pigmentary system consisting of melanin-containing cells in various organs and tissues. We describe the interspecific variation in the visceral pigmentation in three anuran species (Scinax similis, S. fuscovarius, and S. fuscomarginatus). We analyzed the visceral pigmentation of 15 adult males from each species during the reproductive period. The individuals were weighed and measured, and the pigmented visceral cells were classified and documented in stereomicroscope. The shape and amount of pigment cells differed among organs and also among species. Significant differences were detected in the cardiorespiratory system, digestory system, urogenital system, and lumbosacral peritoneum. In the urogenital system, the main difference was observed in the testes, in which only S. fuscomarginatus had varying degrees of pigmentation.

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Kartagener is syndrome is a rare disorder described in dogs determined by the triad situs inversus totalis, chronic sinusitis, and bronchial disease. The clinical signs of chronic respiratory and other less common presentations (such as hydrocephalus and subfertility) are due to a concomitant ciliary dysfunction. This article describes the clinical, radiographic, and computed tomography findings and treatment in a dog affected by Kartagener is syndrome since early months of life. This is the first case report of this syndrome in a domestic dog in Brazil and the only known scientific report in the English Cocker Spaniel.(AU)

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Kartagener is syndrome is a rare disorder described in dogs determined by the triad situs inversus totalis, chronic sinusitis, and bronchial disease. The clinical signs of chronic respiratory and other less common presentations (such as hydrocephalus and subfertility) are due to a concomitant ciliary dysfunction. This article describes the clinical, radiographic, and computed tomography findings and treatment in a dog affected by Kartagener is syndrome since early months of life. This is the first case report of this syndrome in a domestic dog in Brazil and the only known scientific report in the English Cocker Spaniel.

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We report the discovery of a single specimen of a small, terrestrial, lungless caecilian, the second known taxon of lungless caecilians. It differs from all other caecilians in lacking open external nares, and from the large aquatic lungless species described by Nussbaum & Wilkinson (Nussbaum, R. A. & Wilkinson, M. 1995 Proc. R. Soc. Lond. B 261, 331-335) in having no significant skull modifications. All modifications are of 'soft morphology' (covered external nares and choanae, lung and pulmonary vessel loss, etc.). A new genus and species are described to accommodate this form. Aspects of its skull and visceral morphology are described and considered in terms of the possible life history and evolution of the species, and compared with those of other lungless amphibians.

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BACKGROUND: We have not found studies that have measured the peritoneal surface area of each of the walls, organs, mesos, omenta, and peritoneal ligaments in a group of non-eviscerated human cadavers. OBJECTIVES: The objectives of this study were to obtain in fixed non-eviscerated cadavers: (1) the surface values of walls, organs, mesos, omenta, and peritoneal ligaments of each one and all the areas mentioned in the anatomy bibliography and their contribution to supra- and infra-colic portions, visceral and parietal portions of the supra- and infra-colic portions and the total peritoneal surface area, and (2) the relationship between the peritoneal surface values by direct measurement and the values obtained applying the formulas usually used in clinical practice to obtain body surface area. METHODS: The peritoneal surface area of ten female human bodies presenting no abdominal pathologies were measured. They were fixed in 5% formaldehyde solution without the use of perfusion pumps and non-eviscerated, thus maintaining all structures intact. Cellophane was placed directly in situ onto all organs, mesos, omenta, ligaments and parietal walls. Digital imaging was obtained by scanning the models. A length reference was included and the surface was determined by the Scion Image program for Windows. RESULTS: This paper provides for the first time data on each one and all the areas covered by the peritoneum. The total peritoneal surface area was (mean +/- SE) 14,323.62 +/- 824.37 cm(2). The two greater surfaces of peritoneum (39.21% of the total surface) correspond to the jejunum-ileum and its mesentery. The diaphragmatic peritoneum represented the greater area of parietal peritoneum. The supracolic surface was 4,487.46 +/- 196.21 cm(2) (31.79 +/- 1.50%) and the infracolic one of 9,836.16 +/- 732.67 cm(2) (68.21 +/- 1.50%). An interesting result of this work is that the surface of the parietal peritoneum in the supracolic abdomen (1,786.67 +/- 92.58 cm(2), 68.56%) is more than twice that of the infracolic region (756.62 +/- 55.91 cm(2), 31.44%). The visceral peritoneal surface (81.89 +/- 0.99% of the total) was much higher than that of the parietal peritoneum (18.11 +/- 0.99%). This difference is 12 times bigger in the infracolic abdomen. The peritoneal surface area measured in this study in non-eviscerated cadavers represents more than 96% of the one estimated by the above-mentioned formulas. CONCLUSION: The values shown in this paper would provide non-existing information for basic anatomy, and would contribute either to the study of pathologies involving the peritoneum or to their diagnosis and therapies.

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Comparison between related species is a successful approach to uncover conserved and divergent principles of development. Here, we studied the pattern of epithalamic asymmetry in zebrafish (Danio rerio) and medaka (Oryzias latipes), two related teleost species with 115-200 Myr of independent evolution. We found that these species share a strikingly conserved overall pattern of asymmetry in the parapineal-habenular-interpeduncular system. Nodal signalling exhibits comparable spatial and temporal asymmetric expressions in the presumptive epithalamus preceding the development of morphological asymmetries. Neuroanatomical asymmetries consist of left-sided asymmetric positioning and connectivity of the parapineal organ, enlargement of neuropil in the left habenula compared with the right habenula and segregation of left-right habenular efferents along the dorsoventral axis of the interpeduncular nucleus. Despite the overall conservation of asymmetry, we observed heterotopic changes in the topology of parapineal efferent connectivity, heterochronic shifts in the timing of developmental events underlying the establishment of asymmetry and divergent degrees of canalization of embryo laterality. We offer new tools for developmental time comparison among species and propose, for each of these transformations, novel hypotheses of ontogenic mechanisms that explain interspecies variations that can be tested experimentally. Together, these findings highlight the usefulness of zebrafish and medaka as comparative models to study the developmental mechanisms of epithalamic asymmetry in vertebrates.

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We studied how food abundance and consumption regulates torpor use and internal organ size in the Chilean mouse-opossum Thylamys elegans (Dielphidae), a small nocturnal marsupial, endemic in southern South America. We predicted that exposure to food rations at or above the minimum energy levels necessary for maintenance would not lead to any signs of torpor, while reducing food supply to energy levels below maintenance would lead to marked increases in frequency, duration and depth of torpor bouts. We also analyzed the relationship between food availability and internal organ mass. We predicted a positive relationship between food availability and internal organ size once the effect of body size is removed. Animals were randomly assigned to one of two groups and fed either 70, 100 or 130% of their daily energy requirement (DER). We found a positive and significant correlation between %DER and body temperature, and also between %DER and minimum body temperature. In contrast, for torpor frequency, duration and depth, we found a significant negative correlation with %DER. Finally, we found a significant positive correlation between the %DER and small intestine and ceacum dry mass. We demonstrate that when food availability is limited, T. elegans has the capacity to reduce their maintenance cost by two different mechanisms, that is, increasing the use of torpor and reducing organ mass.

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The anatomy of the rabbit is not well known and there is no consensus on the anatomical nomenclature for this species. The objective of this study was to give a complementary description of the peritoneal folds in order to improve the existing knowledge on this species. Eighteen adult rabbits were studied. Ten animals were dissected unfixed and the remaining eight after fixation in formalin. The hepatic ligaments were similar to those of the dog. The transverse mesocolon was absent. The entry to the caudal recess of the omental sac was relatively smaller than that in other domestic species. We consistently found an omental foramen. An amount of fat tissue was almost always found in the proximal mesorchium. The vaginal process was inconstant.

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O tecido adiposo é um órgão dinâmico que secreta vários fatores, denominados adipocinas. Eles estão relacionados, direta ou indiretamente, em processos que contribuem na aterosclerose, hipertensão arterial, resistência insulínica e diabetes tipo 2, dislipidemias, ou seja, representam o elo entre adiposidade, síndrome metabólica e doenças cardiovasculares. Na obesidade, os depósitos de gordura corporal estão aumentados, apresentando conseqüente elevação na expressão e secreção das adipocinas, proporcionalmente ao maior volume das células adiposas. Os diferentes depósitos de gordura, a saber: tecidos adiposos visceral, subcutâneo abdominal, subcutâneo glúteo-femural e intramuscular, possuem grau metabólico e endócrino diferenciados, podendo estar, portanto, interferindo de forma específica nos processos inerentes à adiposidade corporal em obesos e diabéticos. O presente trabalho visa discutir sobre o papel endócrino e metabólico de cada compartimento de tecido adiposo, de modo a avaliar a contribuição dos mesmos nas complicações inerentes à obesidade.

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