996 resultados para 1995_09011531 MOC-37
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Serotonin or 5-hydroxytryptamine (5-HT) is a substance found in many tissues of the body, including as a neurotransmitter in the nervous system, in which may exert varied post-synaptic actions. Inside the neuro-axis, the location of 5-HT neurons is almost restricted to the raphe nuclei of the brainstem, such that 5-HT-immunoreactivity can be considered a marker of the raphe nuclei. The raphe nuclei are located in the brainstem, at or near the midline. The serotonergic groups were originally alphanumerically classified as B1 to B9 towards caudorrostral in rats and can be divided into upper and lower groups. In this study the distribution of serotonergic neurons was studied using immunohistochemistry in the brain of the rock cavy (Kerodon rupestris), a species of rodent endemic to Northeastern Brazil. The cytoarchitectonic location of serotonergic neurons was established in series of adjacent coronal and sagittal sections stained by the Nissl method and immunohistochemistry for 5-HT. Thus, we defined the raphe rostral linear, caudal linear, dorsal, median, and paramedian pontine raphe nuclei, and B9 cluster, constituting the rostral group, and the interpositus, magnus, obscure and palidus, constituting the caudal part of the group, comparable to which has been described for other mammalian species
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The 3-hydroxytyramine/dopamine (DA) is a monoamine of catecholamineric group and consists in the progenitor substantia of synthesis of noradrenaline and adrenaline, having the enzyme tyrosine hydroxylase as a regulator of this process. Nuclei of midbrain expressing DA are the retrorubral field (RRF, A8 group), the substantia nigra pars compacta (SNc, A9 group) and the ventral tegmental area (VTA, A10 group). These nuclei are involved in three complex circuitry called mesostriatal, mesocortical and mesolimbic, which are related directly with various behavioral manifestations such as motor control, reward signaling in behavioural learning, motivation and pathological manifestations of Parkinson s disease and schizophrenia. The aim of this study was describe the morphology of midbrain dopaminergic neurons (A8, A9 and A10) of the rock cavy (Kerodon rupestris), a rodent belonging to the family Caviidae typical of the Brazilian Northeast, which is being adopted as a model for neuroanatomical studies in laboratory of neuroanatomy of the Federal University of Rio Grande do Norte. Coronal sections of brains of the rock cavies were submitted to staining by Nissl s method and immunohistochemistry against tyrosine hydroxylase. The nuclear organization of the midbrain dopaminergic nuclei of the rock cavy is very similar to that found in other animals of the order Rodentia, except by the presence of the tail of substantia nigra, which was found only in the studied species. We concluded that the midbrain dopaminergic nuclei are phylogenetically stable among species, but we think to be it necessary to expand the studies about the particularity found the rock cavy, investigating its occurrence in other species of rodents or investigating its functional relevance
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The midline/intralaminar nuclei form a remarkable group of nuclei of the medial and dorsal thalamus. The midline nuclei, in rats, comprises the paratenial nuclei (PT), paraventricular (PV), intermediodorsal (IMD), reuniens (Re) and rhomboid (Rh). The intralaminar nuclei comprises the central medial (CM), paracentral (PC), central lateral (CL) and parafascicular (PF). Such nuclei have dense serotonergic innervation originating from the brainstem, especially from the so-called ascending activation system. These nuclei, in turn, send projections to various cortical and subcortical areas, specifically to limbic areas, which suggests the important role of this neurotransmitter in the limbic circuitry. The aim of this study was to characterize the distribution pattern and morphology of serotonin fibers in the nuclei of the midline and intralaminar thalamic of rocky cavy (Kerodon rupestris), a tipical rodent from brazilizan northeast. To reach this aim we used four rock cavies adults. Following the transcardially perfusion with paraformaldehyde and brain microtomy steps was performed immunohistochemistry for serotonin (5-HT), Nissl technique and subsequent achievement and image analysis to characterize the cytoarchitecture of these nuclei and the serotonergic fibers visualized. An analysis was made of Relative Optical Density (ROD) to semi-quantify the concentration of serotonin fibers in the areas of interest. Thus, we observed a cytoarchitectonic arrangement of these nuclei similar to that found in rats. In case of fibers distribution, those immunoreactive to 5-HT were presented in a higher concentration according as ROD in the midline nuclei relative to intralaminar; Re being the core which has a higher pixel value followed by the PV , Rh, IMD and PT. In intralaminar CL showed higher pixels, followed by nuclei CM, PC and PF. The serotonergic fibers were classified as number of varicosities and axon diameter, therefore find three types of fibers distributed through this nuclear complex: fibers rugous, granular and semi-granular. In PV fibers predominated rugous; in PT fibers predominated granular; IMD, CL and PF fibers were represented by semi-granular and Re, Rh, PC and CM fibers showed granular and semi-granular. Morphological characterization of serotonergic fibers and differences in density between the nuclei may suggest different patterns of synaptic organization of this neurotransmitter beyond confirming his large repertoire functional
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The secondary phosphate mineral sigloite Fe3+Al2(PO4)2(OH)3·7H2O is the exception to the rule that phosphate mineral paragenesis is related to the final phase of hydrothermal mineralization at low temperatures. Sigloite was formed as an oxidation pseudomorph after paravauxite, during the last supergene paragenetic stage. We have studied the secondary phosphate mineral sigloite Fe3+Al2(PO4)2(OH)3·7H2O using vibrational spectroscopic techniques. Because the mineral is a phosphate mineral, it is readily studied by spectroscopic techniques as the phosphate and hydrogen phosphate units are readily measured. Indeed, sigloite shows the presence of both phosphate and hydrogen phosphate units in its structure. Raman bands at 1009 cm−1 with shoulders at 993 and 1039 cm−1 are assigned to stretching vibrations of and units. The Raman band at 993 cm−1 is assigned to the ν1 symmetric stretching mode of the POH units, whereas the Raman band at 1009 cm−1 is assigned to the ν1 symmetric stretching mode. Raman bands observed at 506, 528, 571, 596, 619 and 659 cm−1 are attributed to the ν4 out of plane bending modes of the PO4 and H2PO4 units. The Raman bands at 2988, 3118 and 3357 cm−1 are assigned to water stretching vibration. The series of bands at 3422, 3449, 3493, 3552 and 3615 cm−1 are assigned to the OH stretching vibrations of the hydroxyl units. The observation of multiple bands gives credence to the non-equivalence of the OH units in the sigloite structure.
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SIC and DRS are related proteins present in only four of the more than 200 Streptococcus pyogenes emm-types. These proteins inhibit complement mediated lysis and/or the activity of certain antimicrobial peptides. A gene encoding a homologue of these proteins, herein called DrsG, has been identified in the related bacterium Streptococcus dysgalactiae subsp equisimilis (SDSE). Here we show that geographically dispersed isolates representing 14 of 50 emm-types examined possess variants of drsG. However not all isolates within the drsG-positive emm-types possess the gene. Sequence comparisons also reveal a high degree of conservation in different SDSE emm-types. To examine the biological activity of DrsG, recombinant versions of two major DrsG variants, DrsGS and DrsGL, were expressed and purified. Western blot analysis using antisera raised to these proteins demonstrated both variants to be expressed and secreted into culture supernatant. Unlike SIC, but similar to DRS, DrsG does not inhibit complement mediated lysis. However, like both SIC and DRS, DrsG is a ligand of the cathelcidin LL-37 and is inhibitory to its bactericidal activity in in vitro assays. The greatest similarity between DrsG and DRS/SIC is found in the signal sequence at the amino terminus and proline rich domains in the C-terminal half of the protein. Conservation of prolines in this latter region also suggests these residues are important in the biology of this family of proteins. This is the first report demonstrating the activity of an AMP inhibitory protein in SDSE. These results also suggest that inhibition of AMP activity is the primary function of this family of proteins. The acquisition of complement inhibitory activity of SIC may reflect its continuing evolution.
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Electron diffraction studies were carried out to establish the icosahedral phase formation in rapidly quenched Ti-37 at% Mn and Ti-24 at% Mn-13 at% Fe alloys. Distortions in the diffraction spots and diffuse intensities in the diffraction patterns were investigated. The existence of a rational approximant structure and a decagonal like phase are also reported.
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As deposited amorphous and crystallized thin films of Ti 37.5% Si alloy deposited by pulsed laser ablation technique were irradiated with 100 keV Xe(+) ion beam to an ion fluence of about 10(16) ions-cm(-2). Transmission electron microscopy revealed that the implanted Xe formed amorphous nanosized clusters in both cases. The Xe ion-irradiation favors nucleation of a fcc-Ti(Si) phase in amorphous films. However, in crystalline films, irradiation leads to dissolution of the Ti(5)Si(3) intermetallic phase. In both cases, Xe irradiation leads to the evolution of similar microstructures. Our results point to the pivotal role of nucleation in the evolution of the microstructure under the condition of ion implantation.
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Resumen: Neste estudo, procuramos definir o sentido da corporeidade em Entralgo, relacionando-o com o pensamento de Lévinas. Segundo Entralgo, o corpo humano era um microcosmos integrado num cosmos. Assim, o corpo é i único objecto do Universo, do qual temos um duplo conhecimento não de fora, como também temos a sua percepção a partir de dentro. Porém, segundo Lévinas, a corporeidade é a expressão do Rosto do Outro, referindo- se como uma prefiguração do Outro, que tem o seu epílogo na parábola do Bom Samaritano. Há, na verdade, uma relação de aproximação antropológica entre o sentido do corpo como forma de manifestar o Outro. Em ti e por ti, tu eras uma pessoa, mas sendo tu uma pessoa, podendo e devendo Eu ver-te e tratar-te como tal pessoa. Os dois pensadores apresentam uma referência em relação à pessoas. Segundo Lévinas a pessoa será responsabilidade.
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Contenido: Trascendencia social de la verdad / La Dirección – Método, sentido y alcance de la investigación metafísica en Heidegger y Sto. Tomás (II) / Octavio N. Derisi – Las nociones de substancia y de causa según el realismo tradicional / R. Garrigou-Lagrange – El ocaso de la educación nueva / Jorge H. Moreno – Notas y comentarios -- Bibliografía
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Contenido: Federico García Lorca en Buenos Aires: una entrevista y un artículo olvidados / Andrew Anderson – Metáforas de la Argentina / Gloria Videla de Rivero – El resumen de textos de carácter académico / Hilda Albano de Vázquez – Hecho de Estampas, de Jacobo Fijman: poetización de un proceso / María Amelia Arancet Ruda – La ideología profética del Palmerín de Oliva / Javier Roberto González – La vanguardia teatral de los años 20 en la obra de Vicente Martínez Cuitiño /Luis Martínez Cuitiño – Coincidencias temáticas en la narrativa contemporánea hispanoamericana y croata: ejemplos de relación entre la nueva historia y la novela / Mirjana Polic Bobic – “Gantasi, Monte Aldín, Daganel y Galdenda, topónimos del Amadís de Gaula” / Aquilino Suárez Pallasá – Literatura de viajes y teatro comparado / Jorge Dubatti – Reseñas bibliográficas