69 research outputs found
Nomenclature and Comparative Morphology of the Teneurin/TCAP/ADGRL Protein Families
The teneurins are a family of glycosylated type II transmembrane proteins synthesized in several tissue from both vertebrate and invertebrate species. These proteins interact with the latrophilins, a group of adhesion G protein-coupled receptors. Both teneurins and latrophilins may have been acquired by choanoflagellates through horizontal gene transfer from a toxin-target system present in prokaryotes. Teneurins are highly conserved in eukaryotes, with four paralogs (TEN1, TEN2, TEN3, and TEN4) in most vertebrates playing a role in the normal neural development, axonal guiding, synapse formation and synaptic maintenance. In this review, we summarize the main findings concerning the distribution and morphology of the teneurins and latrophilins, both during development and in adult animals. We also briefly discuss the current knowledge in the distribution of the teneurin C-terminal associated protein (TCAP), a peptidergic sequence at the terminal portion of teneurins that may be independently processed and secreted. Through the analysis of anatomical data, we draw parallels to the evolution of those proteins and the increasing complexity of this system, which mirrors the increase in metazoan sensory complexity. This review underscores the need for further studies investigating the distribution of teneurins and latrophilins and the use of different animal models
Versalhes Redimido?
Os devastadores conflitos que acompanharam
a desagregação dos estados multinacionais
comunistas na década de 90 estiveram na base
das muitas análises que traçaram um paralelo
entre duas transições de ordens internacionais:
a de 1919 e a de 1989-91. Em ambos os casos,
a cultura política das elites envolvidas na criação
de novos estados independentes haveria de
revelar-se altamente nociva para a constituição
de uma ordem política mais liberal no espaço
dos antigos impérios. A grande diferença é que,
pelo menos, a ordem de Versalhes possuía uma
doutrina consistente para lidar com o desafio do
nacionalismo étnico, a qual assumiu a forma de
um regime internacional de protecção das minorias,
garantido pela SDN. Daí, talvez, a tendência
recente para a reabilitação do Acordo de
Versalhes, depois de durante décadas este ter
sido alvo de uma persistente difamação por
parte da historiografia internacional
Behavioral alterations and Fos protein immunoreactivity in brain regions of bile duct-ligated cirrhotic rats
Hepatic encephalopathy (HE) encompasses a variety of neuropsychiatric symptoms, including anxiety and psychomotor dysfunction. Although HE is a frequent complication of liver cirrhosis, the neurobiological substrates responsible for its clinical manifestations are largely unclear. In the present study, male Wistar rats were bile duct-ligated (BDL), a procedure which induces liver cirrhosis, and on the 21st day after surgery tested in the elevated plus-maze (EPM) and in an open field for anxiety and locomotor activity measurements. Analysis of Fos protein immunoreactivity (Fos-ir) was used to better understand the neurobiological alterations present in BDL animals. Plasma levels of ammonia were quantified and histopathological analysis of the livers was performed. BDL rats showed a significant decrease in the percentage of entries and time spent in the open arms of the EPM, an anxiogenic effect. These animals also presented significant decreases in Fos-ir in the lateral septal nucleus and medial amygdalar nucleus. Their ammonia plasma levels were significantly higher when compared to the sham group and the diagnosis of cirrhosis was confirmed by histopathological analysis. These results indicate that the BDL model induces anxiogenic results, possibly related to changes in the activation of anxiety-mediating circuitries and to increases in ammonia plasma levels.A Encefalopatia hepática (HE) engloba uma variedade de sintomas neuropsiquiátricos, incluindo ansiedade e disfunção psicomotora. Embora seja uma complicação frequente da cirrose hepática, os substratos neurobiológicos responsáveis por suas manifestações clínicas são em grande parte desconhecidos. No presente estudo, ratos Wistar machos foram submetidos ao procedimento cirúrgico de ligação e secção do ducto biliar (BDL; bile-duct ligation), para indução da cirrose hepática e, no 21º dia após a cirurgia, submetidos aos testes comportamentais no labirinto em cruz elevado (LCE) e campo aberto para avaliação da ansiedade e atividade locomotora. A análise da imunorreatividade à proteína Fos (Fos-ir) foi utilizada para melhor compreender as alterações neurobiológicas presentes nos animais do grupo BDL. Foi realizada a quantificação da concentração de amônia plasmática e análise histopatológica dos fígados. Os ratos do grupo BDL mostraram diminuição significativa na porcentagem de entradas e tempo gasto nos braços abertos do LCE, caracterizando efeito ansiogênico. Estes animais também apresentaram redução significativa na Fos-ir no núcleo septal lateral e núcleo medial da amígdala. A concentração plasmática de amônia foi significativamente mais elevada que a do grupo sham e o diagnóstico de cirrose foi confirmado por análise histopatológica. Estes resultados indicam que o modelo de HE induzido por BDL induz efeito ansiogênico possivelmente relacionado à ativação de circuitos mediadores da ansiedade e à hiperamonemia.Universidade Federal de São Paulo (UNIFESP) Departamento de BiociênciasUniversidade de São Paulo Instituto de Ciências Biomédicas Departamento de AnatomiaUNIFESP, Depto. de BiociênciasSciEL
Anatomical Organization of Urocortin 3-Synthesizing Neurons and Immunoreactive Terminals in the Central Nervous System of Non-Human Primates [Sapajus spp.]
Urocortin 3 (UCN3) is a neuropeptide member of the corticotropin-releasing factor (CRF) peptide family that acts as a selective endogenous ligand for the CRF, subtype 2 (CRF2) receptor. Immunohistochemistry and in situ hybridization data from rodents revealed UCN3-containing neurons in discrete regions of the central nervous system (CNS), such as the medial preoptic nucleus, the rostral perifornical area (PFA), the medial nucleus of the amygdala and the superior paraolivary nucleus. UCN3-immunoreactive (UCN3-ir) terminals are distributed throughout regions that mostly overlap with regions of CRF2 messenger RNA (mRNA) expression. Currently, no similar mapping exists for non-human primates. To better understand the role of this neuropeptide, we aimed to study the UCN3 distribution in the brains of New World monkeys of the Sapajus genus. To this end, we analyzed the gene and peptide sequences in these animals and performed immunohistochemistry and in situ hybridization to identify UCN3 synthesis sites and to determine the distribution of UCN3-ir terminals. The sequencing of the Sapajus spp. UCN3-coding gene revealed 88% and 65% identity to the human and rat counterparts, respectively. Additionally, using a probe generated from monkey cDNA and an antiserum raised against human UCN3, we found that labeled cells are mainly located in the hypothalamic and limbic regions. UCN3-ir axons and terminals are primarily distributed in the ventromedial hypothalamic nucleus (VMH) and the lateral septal nucleus (LS). Our results demonstrate that UCN3-producing neurons in the CNS of monkeys are phylogenetically conserved compared to those of the rodent brain, that the distribution of fibers agrees with the distribution of CRF2 in other primates and that there is anatomical evidence for the participation of UCN3 in neuroendocrine control in primates
Análises visual e volumétrica por ressonância magnética das formações hipocampais em um grupo de pacientes com diagnóstico clínico de epilepsia do lobo temporal
Genetic diversity of Leishmania amazonensis strains isolated in northeastern Brazil as revealed by DNA sequencing, PCR-based analyses and molecular karyotyping
Abstract\ud
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Background\ud
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Leishmania (Leishmania) amazonensis infection in man results in a clinical spectrum of disease manifestations ranging from cutaneous to mucosal or visceral involvement. In the present study, we have investigated the genetic variability of 18 L. amazonensis strains isolated in northeastern Brazil from patients with different clinical manifestations of leishmaniasis. Parasite DNA was analyzed by sequencing of the ITS flanking the 5.8 S subunit of the ribosomal RNA genes, by RAPD and SSR-PCR and by PFGE followed by hybridization with gene-specific probes.\ud
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Results\ud
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ITS sequencing and PCR-based methods revealed genetic heterogeneity among the L. amazonensis isolates examined and molecular karyotyping also showed variation in the chromosome size of different isolates. Unrooted genetic trees separated strains into different groups.\ud
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Conclusion\ud
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These results indicate that L. amazonensis strains isolated from leishmaniasis patients from northeastern Brazil are genetically diverse, however, no correlation between genetic polymorphism and phenotype were found.We thank Lucile FloeterWinter for critical reading of the manuscript and Artur T.L. de Queiroz for initial help with phylogenetic analysis. This work is supported by grants from CNPq, FAPESB and PAPES/FIOCRUZ. J.P.C. de Oliveira was supported by a CNPq fellowship; C.I.O. and F.M.C.F were supported by a FAPESB fellowship. AAC, AB, and CIO are senior investigators from CNPq. AB is a senior investigator for Instituto de Investigação em Imunologia (iii).We thank Lucile Floeter-Winter for critical reading of the manuscript and Artur T.L. de Queiroz for initial help with phylogenetic analysis. This work is supported by grants from CNPq, FAPESB and PAPES/FIOCRUZ. J.P.C. de Oliveira was supported by a CNPq fellowship; C.I.O. and F.M.C.F were supported by a FAPESB fellowship. AAC, AB, and CIO are senior investigators from CNPq. AB is a senior investigator for Instituto de Investigação em Imunologia (iii)
Histopatologia da leishmaniose tegumentar por Leishmania braziliensis braziliensis: 1. Padrões histopatológicos e estudo evolutivo das lesões
Frequency of the different mutations causing spinocerebellar ataxia (SCA1, SCA2, MJD/SCA3 and DRPLA) in a large group of Brazilian patients
The Melanin-Concentrating Hormone as an Integrative Peptide Driving Motivated Behaviors
The melanin-concentrating hormone (MCH) is an important peptide implicated in the control of motivated behaviors. History, however, made this peptide first known for its participation in the control of skin pigmentation, from which its name derives. In addition to this peripheral role, MCH is strongly implicated in motivated behaviors, such as feeding, drinking, mating and, more recently, maternal behavior. It is suggested that MCH acts as an integrative peptide, converging sensory information and contributing to a general arousal of the organism. In this review, we will discuss the various aspects of energy homeostasis to which MCH has been associated to, focusing on the different inputs that feed the MCH peptidergic system with information regarding the homeostatic status of the organism and the exogenous sensory information that drives this system, as well as the outputs that allow MCH to act over a wide range of homeostatic and behavioral controls, highlighting the available morphological and hodological aspects that underlie these integrative actions. Besides the well-described role of MCH in feeding behavior, a prime example of hypothalamic-mediated integration, we will also examine those functions in which the participation of MCH has not yet been extensively characterized, including sexual, maternal, and defensive behaviors. We also evaluated the available data on the distribution of MCH and its function in the context of animals in their natural environment. Finally, we briefly comment on the evidence for MCH acting as a coordinator between different modalities of motivated behaviors, highlighting the most pressing open questions that are open for investigations and that could provide us with important insights about hypothalamic-dependent homeostatic integration
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