305 resultados para Terminais ferroviarios


Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this study, two circadian related centres, the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) were evaluated in respect to their cytoarchitecture, retinal afferents and chemical content of major cells and axon terminals with a tract tracer and immunohistochemical techniques in the rock cavy (Kerodon rupestris), a Brazilian caviidae rodent species. The rock cavy SCN is innervated in its ventral portion by terminals from the predominantly contralateral retina. It also contains neurophisin and vasoactive intestinal polypeptide immunoreactive cell bodies and neuropeptide Y and enkephalin immunopositive fibres and terminals and is marked by intense GFAP immunoreactivity. The IGL receives a predominantly contralateral retinal projection, contains neuropeptide Y and nitric oxide synthase producing neurons and enkephalin immunopositive terminals and is characterized by dense GFAP immunoreactivity. This is the first report examining the neural circadian system in a crepuscular rodent species for which circadian properties have been described. The results are discussed comparing with what has been described for other species and in the context of the functional significance of these centres

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The primary and accessory optic systems comprise two set of retinorecipient neural clusters. In this study, these visual related centers in the rock cavy were evaluated by using the retinal innervations pattern and Nissl staining cytoarchigtecture. After unilateral intraocular injection of cholera toxin B subunit and immunohistochemical reaction of coronal and sagittal sections from the diencephalon and midbrain region of rock cavy. Three subcortical centres of primary visual system were identified, superior colliculus, lateral geniculate complex and pretectal complex. The lateral geniculate complex is formed by a series of nuclei receiving direct visual information from the retina, dorsal lateral geniculate nucleus, intergeniculate leaflet and ventral lateral geniculate nucleus. The pretectal complex is formed by series of pretectal nuclei, medial pretectal nucleus, olivary pretectal nucleus, posterior pretectal nucleus, nucleus of the optic tract and anterior pretectal nucleus. In the accessory optic system, retinal terminals were observed in the dorsal terminal, lateral terminal and medial terminal nuclei as well as in the interstitial nucleus of the superior fasciculus, posterior fibres. All retinorecipient nuclei received bilateral input, with a contralateral predominance. This is the first study of this nature in the rock cavy and the results are compared with the data obtained for other species. The investigation represents a contribution to the knowledge regarding the organization of visual optic systems in relation to the biology of species.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The pregeniculate nucleus (PGN) of the primate s thalamus is an agglomerate neuronal having a cap shaped located dorsomedially to the main relay visual information to the cerebral cortex, the dorsal lateral geniculate nucleus (GLD). Several cytoarchitectonic, neurochemical and retinal projections studies have pointed PGN as a structure homologous to intergeniculate leaflet (IGL) of rodents. The IGL receives retinal terminals and appears to be involved in the integration of photic and non-photic information relaying them, through geniculo-hypothalamic tract (TGH), to the main circadian oscillator in mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus. Thus, the IGL participates in the control of the biological rhythm by modulating the activity of the SCN. Pharmacological and IGL injury studies conclude that it is critical in the processing of non-photic information which is transmitted to the SCN. Other studies have found that especially neurons immunoreactive to neuropeptide Y (NPY) respond to this type of stimulation, determined by its colocation with the FOS protein. Has not been determined if the PGN responds, expressing the FOS protein, to the non-photic stimulus nor the neurochemical nature of these cells. Thus, we apply a dark pulse in the specifics circadian phases and analyze the pattern of expression of FOS protein in PGN of the marmoset (Callithrix jacchus). We found that in all animals analyzed the FOS expression was higher in the experimental than in the control group. There was a higher expression of FOS when the dark pulse was applied during the subjective day between the groups. Still, a subregion of the PGN, known by immunoreactive to NPY, had a greater number of FOS-positive cells in relation to his other just close dorsal region. Our data corroborate the theory that the PGN and IGL are homologous structures that were anatomically modified during the evolutionary process, but kept its main neurochemical and functional characteristics. However, injury and hodological studies are still needed for a more accurate conclusion

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The auditory system is composed by a set of relays from the outer ear to the cerebral cortex. In mammals, the central auditory system is composed by cochlear nuclei, superior olivary complex, inferior colliculus and medial geniculate body. In this study, the auditory rombencephalic centers, the cochlear nuclear complex and the superior olivary complex were evaluated from the cytoarchitecture and neurochemical aspects, thorough Nissl staining and immunohistochemical techniques to reveal specific neuron nuclear protein (NeuN), glutamate (Glu), glutamic acid decarboxilase (GAD), enkephalin (ENK), serotonin (5-HT), choline acetyltransferase (ChAT) and calcium-binding proteins calbindin (CB), calretinin (CR), and parvalbumin (PV). The common marmoset (Callithrix jacchus), a little native primate of the Brazilian atlantic forest was used as an experimental animal. As results, it was noted that the cochlear nuclear complex is composed by anteroventral, posteroventral and dorsal nuclei, and the superior olivary complex is constituted by the lateral and medial superior olivary nuclei and the trapezoid body nucleus. Glu, GAD, ENK, ChAT, CB, CR, PV-immunoreactive cells, fibers and terminals besides besides only 5-HT terminals were found unhomogeneously in all nuclei, of both complex. The emerging data are discussed in a comparative and functional context, and represent an important contribution to knowledge of the central auditory pathways in the common marmoset, and then in primates

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The retinal projections in mammals usually reach, classically, three major functional systems: the primary visual system, the accessory optic system, and the circadian timing system. But the retinal projections also reach areas classically considered non-visual, one of which groups the neurons of the zona incerta (ZI), target this study. The primary visual system includes thalamic lateral geniculate complex is formed by the dorsal lateral geniculate nucleus, intergeniculate leaflet and the ventral lateral geniculate nucleus and other Components. The accessory optic system is composed of the small nuclei: nuclei terminal dorsal, lateral, medial and the interstitial nucleus of the superior posterior fasciculus. These nuclei are involved in visuo-motor activities. The circadian timing system is comprised of the suprachiasmatic nucleus of the hypothalamus, that act as master circadian pacemaker, entraining pathways and efferents pathways to the efectors, and the intergeniculate leaflet, that seems to act as a modulator of the pacemaker. The retinal projections too reach classically considered non-visual areas, including the zona incerta. This region is localized in the ventral thalamus and has been implicated in various functional properties including nociceptive and somatosensory processing, motor response, sociosexual behaviour, feeding and drinking, in symptoms of neurodegenerative diseases, arousal and attention. It also displays connection with several areas of central nervous system. The aim of this study was characterize the retinal projection in the zona incerta of Callithrix jacchus (sagüi), a primate of the New World through the anterograde axonal transport of the cholera toxin subunit b and analyze the citoarchicteture using Nissl and NeuN, and neurochemical substances such as serotonin, GABA, VIP, VP, GFAP and binding-calcium proteins. The zona incerta showed a different division of the literature in citoarquitetura, both by means of Nissl as neurochemical by NeuN, with a subdivision ventrolateral and dorsomedial. The neurochemical to the other substances corroborate with this subdivision. The GFAP was almost completely negative for the zona incerta, result non evidenced in previous studies yet. The 16 retinal projection in sagüi, unlike other primates and rodents, reached the caudal portion only. This work helps to make further studies are conducted based on this subdivision and the localization of the neurochemical substances associated with possible behaviors that the zona incerta is involved

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The thalamus plays an important role in the sensorial processing information, in this particular case, the visual information. Several neuronal groups have been characterized as conductors and processors of important sensorial information to the cerebral cortex. The lateral geniculate complex is one to them, and appears as a group very studied once it is responsible, in almost all totality, for the processing of visual information. Among the nuclei that constitute the lateral geniculate complex we highlight the dorsal lateral geniculate nucleus of the thalamus (DLG), the main thalamic relay for the visual information. This nucleus is located rostral and lateral to medial geniculate nucleus and ventral to thalamic pulvinar nucleus in most of the mammals. In the primates humans and non-humans, it presents as a laminate structure, arranged in layers, when observed in coronal sections. The objective of this work was to do a mapping of the retinal projections and a citoarchictetonic and neurochemical characterization of DLG in the marmoset (Callithrix jacchus), a New World primate. The retinal projections were traced by anterograde transport of subunit b of cholera toxin (CTb), the citoarchicteture was described by Nissl method, and to neurochemical characterization immunohistochemicals technical were used to examine the main neurotransmitters and neuroatives substances present in this neural center. In DGL of marmoset thalamus, in coronal sections labeled by Nissl method, was possible to visualize the division of this nucleus in four layers divided in two portions: magnocellular and parvocellular. The retinal projections were present being visualized fibers and terminals immunorreactives to CTb (IR-CTb) in the DLG ipsilateral and contralateral. And through the immunohistochemicals techniques was observed that DLG contain cells, fibers and/or terminals immunoreactives against neuronal nuclear protein, subunits of AMPA 15 glutamate receptors (GluR1, GluR2/3, GluR4), choline acetyltransferase, serotonin, glutamic acid decarboxylase, binding calcium proteins (calbindin, parvalbumin and calretinin), vasopressin, vasoactive intestinal polypeptide, and an astrocyte protein, glial fibrillary acidic protein.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The parabrachial complex (PB) is an area of the brainstem responsible for the processing and transmission of essential physiologic information for the survival of the organisms. This region is subdivided in approximately nine subregions, considering morphology, cytoarchitectural and functional characteristic. Its neurons have an extensive network of connections with other regions of the nervous system. The objective in this work was to map the retinal projection to the PB and make a citoarchitectonic and neurochemical characterization of this region in the common marmoset (Callithrix jacchus), a primate of the New World. The retinal projections were mapped by anterograde transport of the choleric toxin subunit b (CTb). The citoarchitecture was described through the Nissl method, and the neurochemical characterization was made through immunohistochemical technique to the some neurotransmitters and neuroactives substances present in this neural center. In marmoset PB, in the coronal sections labeled by Nissl method, we found a similar pattern to that evidenced in other animal species. The immunoreactivity against CTb was verified in the PBMv in fibers/terminal, characterizing such as retinal innervations in this area. The immunohistochemical technique reveled that the PB contain cells, fibers and/or terminals immunoreactives to the neuronal nuclear protein, Choline acetyl transferase, nitric oxide synthase, serotonin, enkephalin, substance P, Calcium-binding proteins (calbindin, calretinin e parvalbumin), and glial fibrillary acidic protein. The histochemical technique reveled cells and fibers NADPH-diaphorase reactive. Each one of those substances presented a characteristic pattern of demarcation in PB, and some serve as specific markers of subregions

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The hypothalamus is a diencephalic portion located around the third ventricle below the hypothalamic sulcus, limited by the optic chiasm, and by the mammillary bodies, acting as a center that integrates behavioral and homeostatic functions. Serotonin is a neurotransmitter produced in limited sites in the midbrain and brain stem, but is distributed throughout the central nervous system and has many functions, acting through specific receptors that are also distributed throughout the nervous system. Using immunohistochemical techniques, the aim of this study was to delineate the hypothalamic nuclei of the marmoset (Callithrix jacchus) and study the distribution of serotonin transporter and serotonin receptors in the hypothalamus of this species. We used the Nissl method to determine the cytoarchitecture of the hypothalamic nuclei, and immunohistochemistry to reveal the presence of NeuN as a method to determine the contours of the hypothalamic nuclei. As a result, we found serotonin containing fibers and terminals throughout the rostrocaudal extent of the hypothalamus, more concentrated in some nuclei, and even absent in some. Like serotonin, serotonin transporter was observed between pre-optic area and tuberal region of the hypothalamus, in densities and distribution similar to serotonin. The 5-HT1A and 5-HT1B receptors were found with minor differences among itselves regarding the disposition and intensity of staining.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The suprachiasmatic nucleus (SCN) of the anterior hypothalamus, together with the intergeniculate leaflet (IGL) of the thalamus are considered the central components of the circadian timing system (CTS) of mammals. This system is responsible for the generation and regulation of circadian rhythms by establishing a temporal organization of physiological processes and behaviors. The neuronal specific nuclear protein (NeuN) has been widely used as a neuronal marker in several studies. Since glial fibrillary acidic protein (GFAP) is a component of intermediate filaments found in the cytoplasm of astrocytes and is commonly used as a specific marker for these cells. This study aims to identify, in the marmoset, the NeuN immunoreactive neurons and glial cells immunoreactive to GFAP, as well as map the major route of photic synchronization of the STC, retinohypothalamic tract (RHT), and identify the indirect pathway to the SCN and pregeniculate nucleus (PGN) - structure homologous to IGL rodents, using immunohistochemical and cytoarchitectonic techniques. Observed in SCN the presence of neurons immunoreactive to NeuN and terminals immunoreactive subunit b of cholera toxin (CTb), neuropeptide Y (NPY) and serotonin (5- HT). In the PGN noted the presence of the NeuN and NPY immunoreactive neurons and the immunoreactive terminals CTb and 5-HT. Astrocytes are present throughout the extent of the SCN and the PGN this New World primate

Relevância:

10.00% 10.00%

Publicador:

Resumo:

It is undeniable that all the extraordinary technological advances in contemporary society have increased the severe patients expectation and quality of life, especially cancer patients. On the other hand, it is easily verifiable by many researches that it was not possible to advance in the same proportion in caring for the human experience of death. Much is said about the anguish of a man facing death, of cancer patients in terminal stage, about their families, and very little about the feelings, anxieties and ways of coping with the medical professional who deals with this situation, specifically the clinical oncologist. Little is known about the experience of the doctor who has learned to take death as an enemy to be defeated, and increasingly is compelled to live at length with his advertisement. However, we started to watch in recent years a growing interest of researchers in this issue. This study seeks to add to this interest in order to understand the experience of clinical oncologists that accompany dying patients, the meanings they attach to death, ways of coping and the implications for providing care. This is a qualitative study in which was used as a tool for data collection an in-depth interview with the projective using script and scenes. Gadameriana Hermeneutics was used for analysis and interpretation of narratives. The subjects were 10 clinical oncologists who work at two institutions from cancer treatments in the state of Rio Grande do Norte, chosen from a variation in the time working in the specialty (minimum of one year, even old ones). However, you can bring some initial results for the dialogue. It was found that the death is still a topic that causes many difficulties in the daily lives of these professionals, the choice for oncology involves dealing with death without preparation in medical education; being close to the patient in the final moment, supporting the family, coping with own pain of loss and the inability to heal. These are central elements of the narratives. We also have investment in medical training and continuing education in setting up a demand that permeates the discourse of participants. Being able to listen to the subjective world of clinical oncologists will support the work not only for them as other professionals who deal with patients with advanced cancer, providing evidence to understand to what extent the meanings attributed to its know-how before patients on the verge of death interfere with the production of care and allow identify coping strategies in everyday life of these professionals that hinder or facilitate coping with death, promote or preclude the care with others and with themselves. It is hoped that research can contribute to the field of knowledge about the know-how in clinical oncology and their terminal-care-death oncologist-patient relationships, bringing runways capable of promoting a better quality of care in the production of all involved in this process: professionals, patients and families

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This work an algorithm for fault location is proposed. It contains the following functions: fault detection, fault classification and fault location. Mathematical Morphology is used to process currents obtained in the monitored terminals. Unlike Fourier and Wavelet transforms that are usually applied to fault location, the Mathematical Morphology is a non-linear operation that uses only basic operation (sum, subtraction, maximum and minimum). Thus, Mathematical Morphology is computationally very efficient. For detection and classification functions, the Morphological Wavelet was used. On fault location module the Multiresolution Morphological Gradient was used to detect the traveling waves and their polarities. Hence, recorded the arrival in the two first traveling waves incident at the measured terminal and knowing the velocity of propagation, pinpoint the fault location can be estimated. The algorithm was applied in a 440 kV power transmission system, simulated on ATP. Several fault conditions where studied and the following parameters were evaluated: fault location, fault type, fault resistance, fault inception angle, noise level and sampling rate. The results show that the application of Mathematical Morphology in faults location is very promising

Relevância:

10.00% 10.00%

Publicador:

Resumo:

INTRODUÇÃO: Leptospirose é uma zoonose que tem como hospedeiros primários os animais silvestres, sinantrópicos e domésticos. Os humanos comportam-se como hospedeiros terminais e acidentais. Sua prevalência depende dos animais portadores que disseminam o agente, de sua sobrevivência ambiental e do contato de pessoas susceptíveis. Cada sorovar tem um ou mais hospedeiros com diferentes níveis de adaptação. Os focos de leptospirose devem-se aos animais infectados, doentes e assintomáticos, considerados como fontes de infecção ambiental. O objetivo deste estudo foi determinar áreas de risco da infecção leptospírica em cães errantes e pacientes com diagnóstico de leptospirose nos anos de 2006 a 2008, em Maringá, Estado do Paraná, Brasil. MÉTODOS: Foram estudados 335 cães errantes e 25 pacientes. Os soros, tanto dos animais como dos pacientes, foram examinados pela prova de soroaglutinação microscópica (SAM), para pesquisa de anticorpos antileptospíricos. Para determinar áreas de risco e a distribuição espacial da doença foram elaborados mapas temáticos. RESULTADOS: Foram observados 41(12,2%) cães positivos para um ou mais sorovares de leptospiras, e os mais frequentes foram: Pyrogenes (43,9%), Canícola (21,9%) e Copennhageni (19,5%). Nos humanos, a positividade foi de 2 (8%) para os sorovares, Pyrogenes e Hardjo Prajitno e, Pyrogenes e Cynopteri. CONCLUSÕES: A análise espacial revelou que o risco de cães e humanos, no município de Maringá, se infectar com leptospiras está presente tanto em áreas centrais como periféricas, fato que reforça a relevância deste estudo e de ações contínuas de vigilância epidemiológica e ambiental para o controle da doença tanto nos animais como no homem.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

O presente trabalho caracteriza a região 3'-terminal do genoma de um isolado do Southern bean mosaic virus encontrado no Estado de São Paulo (SBMV-SP). O RNA foi extraído de partículas virais purificadas e submetido a RT-PCR usando oligonucleotídeos desenhados para amplificar 972 nt da região 3'-terminal do RNA viral. Foi obtido fragmento de tamanho esperado que inclui o gene da proteína capsidial e a região 3'-terminal não codificadora. O gene da proteína capsidial (ORF4) contém 801 nucleotídeos, incluindo-se o códon de terminação UGA, com seqüência deduzida de 266 aminoácidos e massa molecular estimada de 28.800 Da. Sessenta e um aminoácidos terminais da ORF2 estão sobrepostos na ORF4. O sinal de localização nuclear, encontrado dentro do Domínio R na região 5'-terminal da ORF4 de alguns sobemovírus, não foi identificado no SBMV-SP. Esse dado pode explicar a ausência de partículas virais do SBMV-SP no núcleo celular. A seqüência do SBMV-SP apresentou identidade de nucleotídeos e aminoácidos de, respectivamente, 91% e 93% com o isolado Arkansas (SBMV-ARK) descrito nos EUA. Os resultados obtidos indicam que o SBMV-SP e o SBMV-ARK são isolados muito proximamente relacionados.