78 resultados para Estimulação sensorial
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O AVC é uma grande causa de mortalidade e uma das principais causas de incapacidade entre adultos. O presente estudo visa analisar o estado do sono e da utilização de cartilhas educativas em pacientes com AVC. No primeiro estudo foram abordados os fatores associados com os horários de dormir/acordar e no segundo estudo foi analisado o conhecimento e prática quanto às orientações sobre os hábitos de sono e estimulação cognitiva. No estudo 1 foram avaliados 50 pacientes sendo 28 homens, de faixa etária entre 25 e 90 anos que durante uma semana completaram um diário do sono e o registro de atividades através do Social Rhythm Metric (SRM) e do Indice de Nível de Atividades (ALI) e aplicação do questionário de cronotipo (MEQ). Utilizado o teste de correlação de Spearman verificou-se correlação significativa entre os horários de dormir/acordar com cronotipo e entre os horários de dormir/acordar com SRM e o ALI. No segundo estudo foram abordados 40 pacientes com idade média 56,1 ± 11,9 anos, sendo 15 homens e 25 mulheres; como instrumentos foram utilizados National Institute Health Stroke Scale (NIHSS) e em seguida os pacientes observaram cartilhas educativas sobre hábitos de sono e estimulação cognitiva respondendo se conheciam e se praticavam as orientações apresentadas. A análise estatística realizada através do teste de Fisher obteve como resultado, que das 10 orientações apresentadas sobre os hábitos de sono, 6 foram citadas como conhecidas e apenas 4 foram praticadas. Das 6 orientações cognitivas, não houve diferença significativa entre os que conheciam e não conheciam, mas em 5 delas a maior frequência foi dos pacientes que não praticaram. Os resultados dos estudos indicam a importância de avaliar o cronotipo antes do planejamento de reabilitação, e a necessidade de se estimular o ritmo social a fim de contribuir para a melhoria dos padrões de sono de pacientes. Verificou-se também que em relação ao conhecimento e prática de orientações apresentadas muitos pacientes não conheceram ou não praticaram orientações importantes a respeito de hábitos de sono e de estimulação cognitiva, mesmo na fase crônica da patologia, sugerindo que mais políticas de educação em saúde devem ser implementadas com intuito de causar mudança nos hábitos de vida dos pacientes com AVC
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Cytogenetics analyses in fish are important because they compose a private group among the vertebrates, occupying a central position in the animal evolution. The Perciforms Order, dominant in the marine and freshwater environment, it constitutes a model potentially useful in the genetic evaluation of populations, as well as in the understanding of its evolutionary processes. In spite of this, cytogenetics studies in this great group is scarce, above all for the inhabitants of sandy bottom and pelagics habits. The present work proposed to contribute for the cytogenetic characterization of nine species of fish marine of sandy bottom of the coast of Rio Grande do Norte (Brazil), identifying the evolutionary patterns related to the karyotype in these species and the existence of filogenetics affinities between them and other Perciformes. The animals were collected in the beaches of the Redinha, Ponta Negra and Búzios (Coast of Rio Grande do Norte) and in Saint Peter and Saint Paul Archipelago. Later on they were submitted to the cytogenetics technical that consist of mitotic estimulation, obtaining of mitotics chromosomes, proceeded by techniques of conventional coloration (Giemsa) and chromosomic bands (Ag-RONs and C band). Diploid number and fundamental number equal to 48 were observed in most of the species: Menticirrhus americanus, Ophioscion punctatissimus, Pareques acuminatus (Sciaenidae); Chloroscombrus chrysurus (Carangidae); Echeneis sp. 2 (Echeneidae); Archosargus probatocephalus (Sparidae) and Orthopristis ruber (Haemulidae). Trachinotus goodei (NF=52) (Carangidae) and Echeneis sp. 1 (Echeneidae) (NF=54) presented variation in NF, staying constant a diploid number equal to 48. RONs was situated in pericentromeric position in whole the scianids, and in the species Echeneis sp. 2 (22° pair), O. ruber and A. probatocephalus (1° pair), coinciding with great heterocromatics blocks in M. americanus (1° pair), P. acuminatus (2° pairl) and O. ruber (1° pair). RONs was also located in the telomeric area of the short arm of the 5° and 11° acrocentrics pairs in T. goodei, 4° and 19° pairs of C. chrysurus, 1° pair (sm) of Echeneis sp. 1. The C band detected centromeric blocks in most of the chromosomes of the species of Sciaenidae, Carangidae and Echeneidae, with great blocks in A. probatocephalus (4° pair). Heterocromatic blocks in telomeric areas in submetacentrics of Echeneis sp. 1, and pericentromerics in M. americanus (1° and 8° pairs), O. punctatissimus (1° pair) and P. acuminatus (2° pair) were also observed. It is noticed a marked conservatism cromossomic in the species of the family Scianidae and Haemulidae in what says respect to the number of acrocentrics chromosomes and the location of RONs. Even so it is outstanding the presence of heterocromatinization events during the karyotypic evolution of this family. Already in the families Sparidae and Carangidae, the obtained results reaffirm examples of small variations structural resultants of inversion and translocation Robertsonian, as important mechanisms of diversification karyotipical, as well as a pattern numerical evolutionary conserved, also observed in representatives of Echeneidae of Atlantic in relation to Pacific. The presence of RONs multiple, observed in the species T. goodei and C. chrysurus seems to represent a character derived in the family Carangidae. The results for the species O. ruber and A. probatocephalus suggest the presence of possible geographical or climatic barriers among populations of NE of Brazil in relationship the one of the SE
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The Anguiliformes is constituted by 15 families, 141 sorts and 737 species. In this group eight families possess at least one karyotyped species, where a prevalence of karyotypes with 2n=38 is evidenced chromosomes and high NF, apparently basal for the Anguiliformes. The only family who shows a different karyotypic pattern from the others is the Muraenidae family. In this, of the eight species already described, all of them present 2n=42 chromosomes. Despite the dimension of this Order, few species present karyotypics descriptions. In the present work, a species of Ophichthidae, Myrichthys ocellatus (2n=38, 8m+14sm+10st+6a, NF=70) and three species of Muraenidae, Enchelycore nigricans (2n=42, 6m+8sm+12st+16a, NF=68), Gymnothorax miliaris (2n=42, 14m+18sm+10st, NF=84), Gymnothorax vicinus (2n=42, 8m+6sm+28a, NF=56) and Muraena pavonina (2n=42, 6m+4sm+32a, NF=52), collected in the coast of the Rio Grande do Norte state, Saint Peter and Paul Rocks and in the coast of Bahia state were analyzed. Mitotics chromosomes had been gotten through mitotic stimulation with yeasts. Among the analyzed species, it is observed the presence of characteristic large metacentric chromosomic pairs (≅10µm). As for the structural standard, heterochromatics regions in these species in centromeric position of the majority of the chromosomic pairs and simple ribosomal sites had been evidenced. For the Ophichthidae family, the gotten data corroborate the hypothesis of karyotypic diversification mediated by the occurrence of pericentrics inversions and robertsonians rearrangements, while in the Muraenidae, the identification of larger chromosomic values (2n=42), suggests derived karyotypes, possibly caused by possible chromosomic fissions
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
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Autism comprises a heterogeneous group of neurodevelopmental disorders that affects the brain maturation and produces sensorial, motor, language and social interaction deficits in early childhood. Several studies have shown a major involvement of genetic factors leading to a predisposition to autism, which are possibly affected by environmental modulators during embryonic and post-natal life. Recent studies in animal models indicate that alterations in epigenetic control during development can generate neuronal maturation disturbances and produce a hyper-excitable circuit, resulting in typical symptoms of autism. In the animal model of autism induced by valproic acid (VPA) during rat pregnancy, behavioral, electrophysiological and cellular alterations have been reported which can also be observed in patients with autism. However, only a few studies have correlated behavioral alterations with the supposed neuronal hyper-excitability in this model. The aim of this project was to generate an animal model of autism by pre-natal exposure to VPA and evaluate the early post-natal development and pre-puberal (PND30) behavior in the offspring. Furthermore, we quantified the parvalbumin-positive neuronal distribution in the medial prefrontal cortex and Purkinje cells in the cerebellum of VPA animals. Our results show that VPA treatment induced developmental alterations, which were observed in behavioral changes as compared to vehicle-treated controls. VPA animals showed clear behavioral abnormalities such as hyperlocomotion, prolonged stereotipies and reduced social interaction with an unfamiliar mate. Cellular quantification revealed a decrease in the number of parvalbumin-positive interneurons in the anterior cingulate cortex and in the prelimbic cortex of the mPFC, suggesting an excitatory/inhibitory unbalance in this animal model of autism. Moreover, we also observed that the neuronal reduction occurred mainly in the cortical layers II/III and V/VI. We did not detect any change in the density of Purkinje neurons in the Crus I region of the cerebellar cortex. Together, our results strengthens the face validity of the VPA model in rats and shed light on specific changes in the inhibitory circuitry of the prefrontal cortex in this autism model. Further studies should address the challenges to clarify particular electrophysiological correlates of the cellular alterations in order to better understand the behavioral dysfunctions
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Desde os descobrimentos pioneiros de Hubel e Wiesel acumulou-se uma vasta literatura descrevendo as respostas neuronais do córtex visual primário (V1) a diferentes estímulos visuais. Estes estímulos consistem principalmente em barras em movimento, pontos ou grades, que são úteis para explorar as respostas dentro do campo receptivo clássico (CRF do inglês classical receptive field) a características básicas dos estímulos visuais como a orientação, direção de movimento, contraste, entre outras. Entretanto, nas últimas duas décadas, tornou-se cada vez mais evidente que a atividade de neurônios em V1 pode ser modulada por estímulos fora do CRF. Desta forma, áreas visuais primárias poderiam estar envolvidas em funções visuais mais complexas como, por exemplo, a separação de um objeto ou figura do seu fundo (segregação figura-fundo) e assume-se que as conexões intrínsecas de longo alcance em V1, assim como as conexões de áreas visuais superiores, estão ativamente envolvidas neste processo. Sua possível função foi inferida a partir da análise das variações das respostas induzidas por um estímulo localizado fora do CRF de neurônios individuais. Mesmo sendo muito provável que estas conexões tenham também um impacto tanto na atividade conjunta de neurônios envolvidos no processamento da figura quanto no potencial de campo, estas questões permanecem pouco estudadas. Visando examinar a modulação do contexto visual nessas atividades, coletamos potenciais de ação e potenciais de campo em paralelo de até 48 eletrodos implantados na área visual primária de gatos anestesiados. Estimulamos com grades compostas e cenas naturais, focando-nos na atividade de neurônios cujo CRF estava situado na figura. Da mesma forma, visando examinar a influência das conexões laterais, o sinal proveniente da área visual isotópica e contralateral foi removido através da desativação reversível por resfriamento. Fizemos isso devido a: i) as conexões laterais intrínsecas não podem ser facilmente manipuladas sem afetar diretamente os sinais que estão sendo medidos, ii) as conexões inter-hemisféricas compartilham as principais características anatômicas com a rede lateral intrínseca e podem ser vistas como uma continuação funcional das mesmas entre os dois hemisférios e iii) o resfriamento desativa as conexões de forma causal e reversível, silenciando temporariamente seu sinal, permitindo conclusões diretas a respeito da sua contribuição. Nossos resultados demonstram que o mecanismo de segmentação figurafundo se reflete nas taxas de disparo de neurônios individuais, assim como na potência do potencial de campo e na relação entre sua fase e os padrões de disparo produzidos pela população. Além disso, as conexões laterais inter-hemisféricas modulam estas variáveis dependendo da estimulação feita fora do CRF. Observamos também uma influência deste circuito lateral na coerência entre potenciais de campo entre eletrodos distantes. Em conclusão, nossos resultados dão suporte à ideia de um mecanismo complexo de segmentação figura-fundo atuando desde as áreas visuais primárias em diferentes escalas de frequência. Esse mecanismo parece envolver grupos de neurônios ativos sincronicamente e dependentes da fase do potencial de campo. Nossos resultados também são compatíveis com a hipótese que conexões laterais de longo alcance também fazem parte deste mecanismo
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The radicular cysts (RCs) and dentigerous (DCs), despite having different etiologies, form a pathological cavity lined by epithelium, which grows due to the buildup of fluid inside, as the surrounding bone is reabsorbed and the epithelium will being induced to proliferate. The epithelial proliferation, which has been identified as one of the key processes in the growth of odontogenic cystic lesions, is influenced by growth factors such as EGFR (epidermal growth receptor factor) and podoplanin (PDPN), many of which may have its production stimulated mainly during inflammatory processes. The objective of this research was to evaluate and compare the immunohistochemical expression of EGFR and PDPN in 30 cases of RCs and 30 cases of DCs, semiquantitatively, in light microscopy, associating it with the degree of inflammation, cellular localization of immunostaining and with the immunostained epithelial layers. Data were statistically analyzed by Chi-square test and Fisher exact test, considering a significance level of 5 %. The results showed high immunoreactivity of both proteins in the lesions studied, only statistically significant difference was observed in immunostaining of PDPN (p=0.033), which proved higher in RCs. The other analyzed parameters showed no relevant significant differences. We conclude that, as EGFR and PDPN showed high immunoreactivity in cystic lesions analyzed, these proteins participate the pathogenesis of these lesions through the epithelial stimulation process, despite having different etiologies. Furthermore, it can infer that the higher immunostaining of PDNP in RCs that DCs showed no distinction indicator between the two lesions, regarding their etiologies, once this protein also showed a considerable expression in DCs, independent of the intensity of the inflammatory infiltrate
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Periodontal disease is an infection initiated by oral periodontal pathogens that trigger an immune response culminating in tissue destruction. This destruction is mediated by the host by inducing the production and activation of lytic enzymes, cytokines and the stimulation of osteoclastogenesis. The aim of this study was to compare the immunohistochemical expression of factors involved in bone resorption, RANKL (Ligand Receptor Activator of Nuclear Factor kappa B), OPG (Osteoprotegerin) and TNF-α (tumor necrosis factor alpha) between the gingival healthy, gingivitis and chronic periodontitis and correlate them with clinical parameters. The sample consisted of 83 cases and 12 clinically healthy gums, 42 gingivitis and 29 periodontitis, from 74 adolescent and adult patients with a mean age of 35 years, without systemic changes and non-smokers, predominantly female and race brown. There was no statistically significant difference for the expression of anti-RANKL (p = 0.581) and RANKL / OPG ratio (p = 0.334) when comparing the three conditions, but the anti-OPG and anti-TNF-α showed statistically significant between the types of injury (p = 0.001 and p <0.001, respectively), showing greatest expression in periodontitis. In cases of periodontitis, the variable clinical attachment loss (PIC) was statistically significant and positive correlation, respectively, with immunostaining of anti-RANKL (p = 0.002, p = 0.001 and r = 0.642), anti-OPG (p = 0.018, p = 0.014 and r = 0.451), anti-TNF-α (p = 0.032, p = 0.014 and r = 0.453) and the percentage ratio of RANKL / OPG (p = 0.018, p = 0.002 and r = 0.544). The tooth mobility (MB) showed a statistically significant difference only with immunohistochemical anti-RANKL (p = 0.026), and probing depth (PD) was positively correlated with anti-RANKL (p = 0.028 and r = 0.409), both in cases of periodontitis. Only in cases of gingivitis TNF-α was positively correlated with RANKL (p = 0.012 and r = 0.384) and the RANKL / OPG ratio (p = 0.027 and r = 0.341). Given these results, we conclude that the greatest expression of TNF-α in periodontitis demonstrates a relationship with the progression and severity of periodontal disease and the correlation between all antibodies and clinical attachment loss demonstrates their involvement in periodontal bone resorption
Levantamento exploratório da composição e frações proteicas do leite bovino em propriedades leiteras
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The direct relationship with the processing, industrial yield and price of milk, the importance of the centesimal composition of milk and their protein fractions has increased for both the dairy industry and for the producers, so it is important to identify the possible causes on variation of these components. The aim of this study was to evaluate the effect of the seasons, order of calving and lactation phase on milk composition and protein fractions in dairy farms in the Agreste and Leste meso-regions, of Rio Grande do Norte State (RN). Milk samples were taken in seven milk farms directly from the bulk tanks except for one farm where samples were taken from higher milking cows producers and heifers. The experiment was done in seven properties with milk samples taken directly from the bulk tanks and in one property were collected from higher production cows and heifers. Composition analyses were carried out for both experiments and sensorial trial was performed for the second experiment only. The data results were submitted to analysis of variance (ANOVA) and Tukey test performed for 5% significance level. In the first experiment was observed response of the seasons, dry and rainy season; while in the second, the effect of the order of calving and lactation phase had influence on milk composition and protein fractions. There was significant response (p < 0.05) for season effects but due to farms. The rainy season had higher averages in the protein, lactose, total solids and nonfat dry extract. Multiparous cows had higher CCS, NUL and PCAS milk contents; while, first calving heifers showed higher average for the sensory attribute, color of milk. The final third of lactation was responsible for the elevation of the levels of almost all milk components and their protein fractions
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Parkinson's disease (PD) is one of the most common neurodegenerative brain disorders and is characterized primarily by a progressive degeneration of dopaminergic neurons nigroestriatais. The main symptoms of this disease are motor alterations (bradykinesia, rigidity, tremor at rest), which can be highly disabling in advanced stages of the condition. However, there are symptomatic manifestations other than motor impairment, such as changes in cognition, mood and sensory systems. Animal models that attempt to mimic clinical features of PD have been used to understand the behavioral and neural mechanisms underlying neurophysiological disturbance of this disease. However, most models promote an intense and immediate motor impairment, consistent with advanced stages of the disease, invalidating these studies for the evaluation of its progressive nature. The administration of reserpine (a monoamine depletor) in rodents has been considered an animal model for studying PD. Recently we found that reserpine (in doses lower than those usually employed to produce the motor symptoms) promotes a memory deficit in an aversive discrimination task, without changing the motor activity. It was suggested that the administration of this drug in low doses can be useful for the study of memory deficits found in PD. Corroborating this data, in another study, acute subcutaneous administration of reserpine, while preserving motor function, led to changes in emotional context-related (but not neutral) memory tasks. The goal of this research was to study the cognitive and motor deficits in rats repeatedly treated with low doses of reserpine, as a possible model that simulates the progressive nature of the PD. For this purpose, 5-month-old male Wistar rats were submitted to a repeated treatment with vehicle or different doses of reserpine on alternate days. Cognitive and motor parameters and possible changes in neuronal function were evaluated during treatment. The main findings were: repeated administration of 0.1 mg / kg of reserpine in rats is able to induce the gradual appearance of motor signs compatible with progressive features found in patients with PD; an increase in striatal levels of oxidative stress and changes in the concentrations of glutamate in the striatum were observed five days after the end of treatment; in animals repeatedly-treated with 0. 1 mg/kg, cognitive deficits were observed only after the onset of motor symptoms, but not prior to the onset of these symptoms; 0.2 mg / kg reserpine repeated treatment has jeopardized the cognitive assessment due to the presence of severe motor deficits. Thus, we suggest that the protocol of treatment with reserpine used in this work is a viable alternative for studies of the progressive appearance of parkinsonian signs in rats, especially concerning motor symptoms. As for the cognitive symptoms, we suggest that more studies are needed, possibly using other behavioral models, and / or changing the treatment regimen
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Down syndrome (DS) is one of the most frequent causes of intellectual disability, affecting one in every 600 to 1000 live births. Studies have demonstrated that people with DS have a lower capacity for short-term memory (STM) and working memory (WM), which affects their capability to learn new words and to follow spoken instructions, specially when they involve multiple information or consecutive orders/orientations. It seems that the basis of the learning process, as it happens with language and mathematics comprehension and reasoning, relies in the STM and WM systems. Individuals with DS are increasingly included in mainstream education, and yet, very few researches have been conducted to investigate the influence of memory development and the type of enrollment (regular school and special school). This study investigated the relationship between the type of school enrollment with the performance on STM tests and also, the relationship of this performance with early stimulation (ES). The tests used in the first research were the digit span, free recall, word recognition and subtests of the Wechsler Intelligence Scale for Children Third Edition (WISC-III). Individuals enrolled in the regular schools group had higher scores on the digit span test and the subtests of the WISC-III. In the free recall and recognition tests, no differences were found. This study indicates that the type of enrollment might influence the memory development of individuals with DS and clearly points the need for future investigations. In the second research, the tests used were the digit span, free word recall and subtests of the WISC-III. The test results showed better performance by adults that received ES before six months of age. The studies showed improvement in STM both in people who attended or were attending regular school, as well as those who benefited from ES before six months of age. However, some issues still need to be better understood. What is the relation between this stimulation with the individual s education? Since ES may reflect a greater family involvement with the individual, what is the role of emotional components derived from this involvement in the cognitive improvement? These and other questions are part of the continuity of this study
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The visual system is an important link between the animal and the environment, com profound influences on the habits and lifestyle in various habitats. Adaptive mechanismsto the temporal niche are present in the visual system of many vertebrates, involving changins in ocular dimensios and design, retinal cell distribution and organization of neurochemical circuits related to the retinal resolution or sensitivity. The sensory system of the eye is represented by the retina, whose organization is responsible by receipty, initial analysis, and transmission of the information to the brain. The knowledge of the position of the eyes in the head and the distribution of retinal cells allow to identify adaptive aspects of each species to its visual field, which is characteristic to the ecological niche it occupies. In this research, we study eye anatomical characteristics and retina neurochemical features of the rock cavy (Kerodon rupestris), a tipical Brazilian rodent from the suborder Hystricomorpha, family Caviidae. The rock cavy has lateral eyes well constitute bony orbit and well differentiated extrinsic muscle. The study of the descriptive and morphometric anatomy of the showed mean values of axial diameter 10.7±0,5mm and equatorial diameter 11.6±0.7mm. The pupil is slit shaped and the lens has mean axial diameter 5.4±0.03 mm, corresponding to ~45% of the axial diameter of the eye. The posterior nodal distance and the retinal magnification factor were estimated at 6.74 mm e 118 μm/grau, respectively. Flat mounts were processed for Nissl stain, and the topographic distribution of ganglion cells showed a moderate visual band, just below the optic disc, with higher density in the ventral retina. Retinal vertical sections and flat mounts were processed for immunohistochemistry to visualize tyrosine hydroxilase (TH) and thus two types of TH+ cells were detected. Type 1 cells had strong TH-immunoreactivity, the body cell varied from 120.047 to 269.373 μm2 stratifying in the sublamina 1 of the IPL. Type 2 cells were weakly TH-imunoreactive, had cell body located mostly in the IPL, varying from 54.848 to 177.142 μm2, constituting ~10% of the TH+ cells. Both cell types exhibited similar topographic distribution with higher density found in a horizontal band along of the naso-temporal axis in the dorsal retina. The total population of dopaminergic cells was 2,156±469,4 cells, occupying an average area of 198,164 μm2. The presence of cones and rods was detected by immunohistochemistry in vertical sections and flat mounts. S cones density is around 10 times smaller than L cones, with different degree of spatial organization. Other retinal neuronal populations of the rock cavy were also detected in vertical sections with specific markers. Comparative analysis of the anatomical characteristics of the rock cavy eye 12 suggest that it was designed to acquire higher sensitivity to light, at expense of image sharpness, compatible with a vision at mesopic conditions. Additionally, the distribution of the 2 subtypes of dopaminergic cells in a naso-temporal band in the dorsal retina seems suitable to a gain in sensitivity, coherent with an animal with predominantly crepuscular activity pattern
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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.
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Memory and anxiety are related phenomena. Several evidences suggest that anxiety is fundamental for learnining and may facilitate or impair the memory formation process depending of the context. The majority of animal studies of anxiety and fear use only males as experimental subjects, while studies with females are rare in the literature. However, the prevalence in phobic and anxiety disorders is greater in women than in men. Moreover, it is known that gender maybe influence benzodiazepine effects, the classic drugs used for anxiety disorders treatment. In this respect, to further investigate if fear/anxiety aspects related to learning in female subjects would contribute to the study of phobic and anxiety disorders and their relationship with learning/memory processes, the present work investigates (a) the effects of benzodiazepine diazepam on female rats performance in a aversive memory task that assess concomitantly anxiety/emotionality, as the interaction between both; (b) the influence of estrous cycle phases of female rats on diazepam effects at aversive memory and anxiety/emotionality, and the interaction between both and (c) the role of hormonal fluctuations during estrous cycle phases in absence of diazepam effects in proestrus, because female rats in this phase received or not mifepristone, the antagonist of progesterone receptor, previously to the diazepam treatment. For this purpose, the plus maze discriminative avoidance task, previously validated for studies of anxiety concomitantly to learning/memory, was used. The apparatus employed is an adaptation of a conventional plus maze, with two opens arms and two closed arms, one of which presenting aversive stimulation (noise and light). The parameters used were: time in non-aversive arm compared to time in aversive and percentage of time in aversive arm on several temporal divisions, in order to evaluate memory; percentage of time in open arms, risk assessment, head dipping and end exploring to evaluate anxiety ; and distance traveled for locomotion. In experiment I, we found anxiolytic effect of diazepam only for 4 mg/kg dose, however the amnestic effect appear at a dose of 2 mg/kg. In second experiment, rats were divided in groups according estrous cycle phase (metaestrus/diestrus, proestrus e estrus). In this experiment, when we considered estrous cycle phase or diazepam treatment, the results did not demonstrate any differences in anxiety/emotionality parameters. The amnestic effects of diazepam occur in female rats in metestrus/diestrus and estrus and is absent in proestrous rats. Proestrous female rats that received mifepristone exhibited the amnestic effect of diazepam and also anxiolytic effects, that it was not previously observed in this dose. The results have demonstrated dissociation of anxiolytic and amnestic diazepam effects, not previously observed in males; the absence of amnestic effect of diazepam in proestrous phase; and the possible role of progesterone in aversive memory over diazepam effect, because the mifepristone, associated with diazepam, caused amnestic effect in proestrus
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Sweeteners provide a pleasant sensation of sweetness that helps the sensory quality of the human diet, can be divided into natural sweeteners such as fructose, galactose, glucose, lactose and sucrose, and articial sweeteners such as aspartame, cyclamate and saccharin. This work aimed to study the thermal stability of natural and artificial sweeteners in atmospheres of nitrogen and syntetic air using thermogravimetry (TG), derivative thermogravimetry (DTG), Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). Among the natural sweeteners analyzed showed higher thermal stability for the lactose and sucrose, which showed initial decomposition temperatures near 220 ° C, taking advantage of the lactose has a higher melting point (213 ° C) compared to sucrose (191 ° C). The lower thermal stability was observed for fructose, it has the lowest melting point (122 °C) and the lower initial decomposition temperature (170 °C). Of the artificial sweeteners studied showed higher thermal stability for sodium saccharin, which had the highest melting point (364 ° C) as well as the largest initial decomposition temperature (466 ° C under nitrogen and 435 ° C in air). The lower thermal stability was observed for aspartame, which showed lower initial decomposition temperature (158 ° C under nitrogen and 170 ° C under air). For commercial sweeteners showed higher thermal stability for the sweeteners L and C, which showed initial temperature of thermal decomposition near 220 ° C and melting points near 215 ° C. The lower thermal stability was observed for the sweetener P, which showed initial decomposition temperature at 160 ° C and melting point of 130 °C. Sweeteners B, D, E, I, J, N and O had low thermal stability, with the initial temperature of decomposition starts near 160 °C, probably due to the presence of aspartame, even if they have as the main constituent of the lactose, wich is the most stable of natural sweeteners. According to the results we could also realize that all commercial sweeteners are in its composition by at least a natural sweeteners and are always found in large proportions, and lactose is the main constituent of 60% of the total recorded