Functional morphology of the tongue of snake Bothrops jararaca (Reptilia: Squamata)

The tongue has a series of functions that can be related to feeding, such as transporting food to the back of the mouth, sensory function and capturing prey. The tongue of the reptiles has great morphological and functional variations between orders. This study aimed to described the morphological characteristics of the tongue of the snake Bothrops jararaca, relating them to the habitat and eating habits of this species. This work used five adult animals which were collected in the municipality of Viçosa, in the Zona da Mata Mineira region. The animals were euthanized, with anesthetic overdose, for the removal of the tongue, which was used for histological processing and scanning electron microscopy. The tongue had stratified epithelium with an extensive degree of keratinization and pigmentation. It was shown to be strongly muscular, innervated and vascularized. Keratinization and pigmentation is an important protection mechanism, due to the protrability of this organ, which is exposed to the environment to capture odors and locate prey. Mucous secretion was present as an important tool for lubrication and protection of the lingual lining. The tongue of the B. jararaca has no papillae and taste buds, being its function strictly olfactory, in association with the vomeronasal organ.Asociación Herpetológica Argentin

Functional morphology of the tongue of lizard Salvator merianae (Reptilia: Squamata)

The reptilian tongue has morphological and functional variations according to the feeding mechanisms and habitat of the species. This study aimed to understand the morphofunctional characteristics of the tongue of the lizard Salvator merianae, through anatomical, histological and scanning electron microscopy analyses. This study involves five adult animals, which were collected in the municipality of Viçosa, Minas Gerais, from Brasil. The tongue of S. merianae was protractile and bifid, important to drive molecules from the environment to the vomeronasal organ and thus identify odors and locate prey, besides being strongly muscular and with keratinized and pigmented stratified epithelium for protection. Mucous secretion was present as an important tool for lubrication and protection in view of the protrability of the tongue and the great presence of bacteria. Morphological specialization of the S. merianae tongue reflect its direct participation in food assimilation, with squamiform papillae for the mechanical function of maintaining prey in the oral cavity and contributing to swallowing. Taste buds were not found, which excludes the tongue participation in the taste, although it has olfactory sensory function in association with the vomeronasal organ.Asociación Herpetológica Argentin

Therapeutic and Prophylactic Potential of Vitamin D for Multiple Sclerosis

A plethora of investigations demonstrated that vitamin D (VitD) has a broad immunomodulatory potential. It induces tolerogenic dendritic cells in vitro leading to the development of regulatory T cells that have a key role in immunomodulation of autoimmune diseases including multiple sclerosis (MS). Studies showed that many MS patients present lower serum levels of VitD than healthy subjects. In addition, VitD supplementation has been associated with a reduced relative risk of developing MS. Considering the alterations in VitD levels in patients and also the immunomodulatory properties of VitD, it would be interesting to evaluate VitD potential as a tolerogenic adjuvant in experimental models of MS. In this context, our research team has been investigating strategies employing VitD to establish an in vivo tolerance state toward central nervous system antigens in experimental autoimmune encephalomyelitis (EAE). We observed that the association between a myelin peptide and VitD determined both therapeutic and prophylactic effects on EAE development

Prática pedagógica educomunicativa (PPE) e escrita colaborativa

No presente artigo teve-se por objetivo refletir sobre as possibilidades de incorporação dos benefícios da conectividade para a produção coletiva do conhecimento a partir da Educomunicação, ou seja, da inter-relação entre Educação e Comunicação. O estudo chama a atenção para o fato de que ensinar e aprender na sociedade contemporânea, repleta por elementos midiáticos, indica a necessidade da mediação e do diálogo entre as referências midiáticas dos alunos e as experiências proporcionadas no ambiente escolar. Diante da mobilidade permitida pelos meios digitais, concluiu-se que é possível, por exemplo, trabalhar a escrita colaborativa de maneira crítica e ativa com os alunos e professores nos espaços escolares e para além dos muros da escola, por meio de uma Prática Pedagógica Educomunicativa (PPE) aliada a uma alfabetização midiática ou “digital” e ao multiletramento.Palavras-chave: Educomunicação. Prática Pedagógica Educomunicativa (PPE). Escrita colaborativa

Identification of enteroendocrine cells of Tropidurus torquatus and Salvator merianae (Squamata: Lacertilia)

The Squamata lizards Tropiduros torquatus and Salvator merianae are omnivores with different diets and foraging strategies, which requires adequate physiological responses of enteroendocrine cells, since they control digestive events, gastrointestinal epithelium renewal, metabolism and food intake. Thus, we aim to describe the distribution and frequency of enteroendocrine cells in the digestive tract of these two lizard’s species. Five individuals of each species were collected, euthanized and the digestive organs removed. Histological sections were submitted to the techniques of Grimelius for argyrophilic cells and Masson-Fontana for argentaffin cells. Both endocrine cells were found in the lining and glandular epithelium, with a pyramidal, oval, rounded, or elongated shape. Argyrophilic cells were observed in both species, predominantly in the stomach, but absent in the cranial esophagus. Argentaffin cells were distributed in almost the entire digestive tract but absent in the cranial portion of the esophagus and small intestine in both species, and with high frequency in the T. torquatus pyloric region. The absence of argentaffin cells in the cranial portion of the small intestine is intriguing and may reveal greater neural control over certain secretomotor functions involving this segment. We concluded that the inter-specific and inter-regional variations in the distribution and frequency of these cells may reflect the regulatory functions and mechanisms of each organ, taking also into account the oscillations of the food and nutritional status of animals in the wild.Os lagartos Squamata Tropiduros torquatus e Salvator merianae são onívoros com diferentes dietas e estratégias de forrageamento, o que requer respostas fisiológicas adequadas de células enteroendócrinas, uma vez que estas controlam os eventos digestivos, a renovação do epitélio gastrointestinal, o metabolismo e a ingestão alimentar. Portanto, pretendemos descrever a distribuição e frequência de células enteroendócrinas no trato digestivo destas duas espécies de lagartos. Foram coletados cinco indivíduos de cada espécie, eutanasiados e os órgãos digestivos removidos. Seções histológicas foram submetidas às técnicas de Grimelius para células argirófilas e Masson-Fontana para células argentafins. Ambas as células endócrinas foram encontradas no epitélio de revestimento e glandular, com formatos piramidal, oval, arredondado ou alongado. Células argirófilas foram observadas em ambas as espécies, predominantemente no estômago, mas ausentes no esôfago craniano. As células argentafins estiveram distribuídas em quase todo o trato digestivo, mas ausentes na porção cranial do esôfago e intestino delgado em ambas as espécies, e com alta frequência na região pilórica de T. torquatus. A predominância das células endócrinas no estômago pode estar relacionada, por exemplo, à maior permanência do alimento neste órgão, ao contrário do esôfago. A ausência de células argentafins na porção cranial do intestino delgado é intrigante e pode revelar maior controle neural sobre certas funções secretomotoras envolvendo este segmento. Nós concluímos que as variações inter-específicas e interregionais na distribuição e frequência destas células podem refletir as funções e mecanismos regulatórios de cada órgão, levando-se também em conta as oscilações do estado alimentar e nutricional dos animais na natureza.Asociación Herpetológica Argentin

Formas de fósforo em folhas e suas relações com a composição do mosto e a produção em videiras

The objective of this work was to evaluate phosphorus forms in grape leaves and their relationships with must composition and yield in grapevines grown in a Typic Hapludalf with different available P contents. Two experiments were carried out with Vitis vinifera cultivars, one with 'Tannat' and the other with 'Cabernet Franc' grapes. Experiment 1 consisted of two vineyards of 'Tannat', with the following P content in the soil: V1, 11.8 mg kg-1 P; and V2, 34.6 mg kg-1 P. Experiment 2 consisted of two vineyards of 'Cabernet Franc', with the following P content in the soil: V1, 16.0 mg kg-1 P; and V2, 37.0 mg kg-1 P. Leaves were collected at flowering (FL) and veraison (V), and, after their preparation, P forms were evaluated. Yield and must composition were assessed. The highest yield was observed in V2 of experiment 1 and in V2 of experiment 2. Total P content and P forms in leaves at FL and V have no relationship with yield parameters; however, total P content in leaves has a relationship with anthocyanin content in the must of 'Tannat' grapevines. Therefore, P fractionation in leaves predicts neither grapevine yield nor must composition.O objetivo deste trabalho foi avaliar as formas de fósforo em folhas e suas relações com a composição do mosto e a produção em videiras cultivadas em um Argissolo Vermelho distrófico típico, com diferentes teores de P disponível. Dois experimentos foram realizados com cultivares de Vitis vinifera, um com uvas 'Tannat' e outro com 'Cabernet Franc'. O experimento 1 consistiu de dois vinhedos de 'Tannat', com os seguintes teores de fósforo no solo: V1, 11,8 mg kg-1 de P; e V2, 34,6 mg kg-1 de P. O experimento 2 consistiu de dois vinhedos de 'Cabernet Franc', com os seguintes teores de fósforo no solo: V1, 16,0 mg kg-1 de P; e V2, 37,0 mg kg-1 de P. Coletaram-se as folhas ao florescimento (FL) e ao início da maturação (IM), e, após a preparação delas, analisaram-se as formas de P. A produtividade e a composição do mosto foram avaliadas. A maior produtividade foi observada no V2 do experimento 1 e no V2 do experimento 2. O teor total de P e suas formas nas folhas ao FL e IM não apresentam relação com os parâmetros produtivos; no entanto, o teor de P total nas folhas apresenta relação com o teor de antocianinas no mosto de videiras 'Tannat'. Portanto, o fracionamento de P nas folhas não prediz a produtividade da videira nem a composição do mosto

Hystometric evaluation of nickel chronic exposure effects on large instestine of adult Wistar male rats

The ingestion of considerable amounts of water or food contaminated with nickel can be very toxic. The present work was conducted aiming to evaluate the effects of nickel exposures on ascending colon of adult Wistar male rats at hystometric level. We used 12 animals that were divided in a control (ingested uncontaminated water) and a nickel-contaminated (i.e., 25 mg de nickel/L of water) groups. Nickel chloride was offered in declorinated water and the experiment had a 56 days exposure period. A portion of the ascending colon was removed of the animals and subjected to hystological labelling processes using blue toluidin (for general hystometric description), Alcian Blue (AB, for acid mucins) and periodic acid-Schiff (PAS) technique (for neutral mucins). The potential differences between groups were desgined by applying the Whitney test and t test (p < 0.05). The crypts were smaller for the nickel-contaminated group, even though these organism exhibited broader and higher crypts. Nickel-contaminated animals exhibited a smaller amount of calyceform cells with AB and PAS positive reactions as well as a less mucus quantities when compared with nickel-uncontaminated animals. Such reductions on the amount of calyceform cells with AB and PAS positive reactions may be related wiht the shallower crypts, which possibly reduced the synthesis and secretion of mucins, compromissing the functional aspects (e.g., lubrification and intestinal mucosa protection) of the nickel-contaminated large intestines. Interestingly, the wider and higher crypts and higher epithelium collumn on the nickel-contaminated animals may represent a relevant trade-off for the intestinal mucosa protection

Experimental Autoimmune Encephalomyelitis Development Is Aggravated by Candida albicans

Multiple sclerosis (MS) is an inflammatory/autoimmune disease of the central nervous system (CNS) mainly mediated by myelin specific T cells. It is widely believed that environmental factors, including fungal infections, contribute to disease induction or evolution. Even though Candida infection among MS patients has been described, the participation of this fungus in this pathology is not clear. The purpose of this work was to evaluate the effect of a Candida albicans infection on experimental autoimmune encephalomyelitis (EAE) that is a widely accepted model to study MS. Female C57BL/6 mice were infected with C. albicans and 3 days later, animals were submitted to EAE induction by immunization with myelin oligodendrocyte glycoprotein. Previous infection increased the clinical score and also the body weight loss. EAE aggravation was associated with expansion of peripheral CD4+ T cells and production of high levels of TNF-α, IFN-γ IL-6, and IL-17 by spleen and CNS cells. In addition to yeast and hyphae, fungus specific T cells were found in the CNS. These findings suggest that C. albicans infection before EAE induction aggravates EAE, and possibly MS, mainly by CNS dissemination and local induction of encephalitogenic cytokines. Peripheral production of encephalitogenic cytokines could also contribute to disease aggravation