510 resultados para substância


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To the vertebrates, maintain body balance against the gravitational field and be able to orient themselves in the environment are fundamental aspects for survival, in which the participation of vestibular system is essential. As part of this system, the vestibular nuclear complex is the first central station that, by integrating many information (visual, proprioceptive), and the vestibular, assumes the lead role in maintaining balance. In this study, the vestibular nuclear complex was evaluated in relation to its cytoarchitecture and neurochemical content of cells and axon terminals, through the techniques of Nissl staining and immunohistochemistry for neuronal specific nuclear protein (NeuN), glutamate (Glu), substance P (SP), choline acetyltransferase (ChAT) (enzyme that synthesizes acetylcholine-Ach) and glutamic acid decarboxylase (GAD) (enzyme that synthesizes gamma-amino butyric acid-GABA). The common marmoset (Callithrix jacchus) was used as experimental animal, which is a small primate native from the Atlantic Forest in the Brazilian Northeast. As results, the Nissl technique, complemented by immunohistochemistry for NeuN allowed to delineate the vestibular nucleus superior, lateral, medial and inferior (or descending) in the brain of the common marmoset. Neurons and terminals immunoreactive to Glu and ChAT and only immunoreactive terminals to SP and GAD were seen in all nuclei, although in varying density. This study confirms the presence in the vestibular nuclei of the common marmoset, of Glu and SP in terminals, probably from the first order neurons of vestibular ganglion, and of GABA in terminals, presumably from Purkinge cells of the cerebellum. Second-order neurons of the vestibular nuclei seem to use Glu and Ach as neurotransmitters, judging by their expressive presence in the cell bodies of these nuclei in common marmosets, as reported in other species

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Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy in the oral cavity and reach a large number of individuals, has become an important public health problem. Studies have demonstrated changes in pathway components BMP in various types of cancers as prostate, colon, breast, gastric and OSCCs. Is the current knowledge that these proteins may exert pro-tumor effect in more advanced stages of neoplastic development coming to favor progression and invasion tumor. The inhibition of the signaling pathway BMP-2 through its antagonists, have shown positive results of antitumor activity and use of Noggin may be a novel therapeutic target for cancer. Given this evidence and the few studies with BMP-2, Noggin and OSCC, the objective of this research was to evaluate the effect of BMP-2 and its antagonist Noggin on proliferation and migration cell in line of cell cultures of human tongue squamous cell carcinoma (SCC25). The study was divided in three groups, a control group, where SCC25 cells suffered no treatment, a BMP-2 group, in which cells were treated with 100ng/ml of BMP-2 and a group of cells that were treated with 100ng/ml of Noggin. For the proliferation assay and cell cycle were established three time intervals (24, 48 and 72 hours). Proliferative activity was investigated by trypan blue and cell cycle analysis by staining with propidium iodide flow cytometry. The potential for migration / invasion of SCC25 cells was performing by a cell invasion assay using Matrigel in a 48-hour interval. The proliferation curve showed a higher proliferation in cells treated with BMP-2 in 72 hours (p < 0.05), and lower overgrowth and cell viability in Noggin group. Recombinant proteins favored a greater percentage of cells in cell cycle phase Go/G1 with a statistically significant difference in the interval of 24 hours (p < 0.05). BMP- 2 produced a greater invasion of cells studied as well as its antagonist Noggin inhibits invasion of cells (p < 0.05). Thus, these results indicate that BMP-2 promotes malignant phenotype, dues stimulates proliferation and invasion of SCC25 cells and, its antagonist Noggin may be an alternative treatment, due to inhibit the tumor progression

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Caffeine is considered the most consumed psychostimulant in the world, presenting several central and peripheral effects. In the Central Nervous System the major effect occur by its antagonistic activity at the A1 and A2a subtypes of the adenosine receptors. These receptors are responsible for the slow-wave sleep induction, and their binding, caused by the consumption of foods and beverages that contain caffeine, cause behaviors like increase of alertness, mood and locomotion. The effects of caffeine on memory are still discussed because of the diversity of experimental protocols. Also, it does not have the same effects on all stages of the processing of memory - acquisition, consolidation and recall. Thus, using the marmoset (Callitrhix jacchus) as subject, we aim to evaluate the effects of caffeine on the memory of this primate through the conditioned place preference paradigm, where the animal selects a context by presence of food. This cognitive task consists of five phases. The first phase was two sessions of pre-exposure, in which they were evaluated for preference for any compartment of the apparatus. Then, we proceeded the training, conditioning the animals to the food-present context for 8 days. Then, there was administration of caffeine or placebo (10mg/kg) for 8 consecutive days, during the pre-sleep phase, where the 20 animals were distributed in two groups: placebo and repeated. The forth phase was one day of retraining, a re-exposure of the apparatus to the marmosets followed by the administration of caffeine (for the repeated group and a new group called abstinence) or placebo (for placebo and abstinence groups). Finally, was the test where we evaluated if the subjects learned where the food was present. Moreover, in this work we evaluate the existence of differences between females and males on the task, and the locomotor activity for the experimental groups. The results showed that in the pre-exposure phase the animals were habituated on the apparatus and did not present differences for any contexts. In training, they were able to learn the conditioning task, independent of gender. For the retraining, the two groups exhibited more interactions in rewarded context than that in non-rewarded context. Nevertheless, in the locomotor activity, the repeated group moved similarly in contact with the apparatus and outside of it. In the other hand, the animals of the placebo group moved more when in contact with the apparatus. In the test phase, the marmosets under influence of caffeine presented an increase in the locomotor activity when compared with the placebo group, corroborating works that show this increase in locomotion. In the learning evaluation, the continuous and abstinence groups had a bad performance in the task in relation to the placebo and acute groups. This suggests that the prolonged administration of caffeine disrupts the memories because it affected sleep, which is largely responsible offline processing of memories

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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

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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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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Central Nervous System are the most common pediatric solid tumors. 60% of these tumors arise in posterior fossa, mainly in cerebellum. The first therapeutic approach is surgical resection. Malignant tumors require additional strategies - chemotherapy and radiotherapy. The increasing survival evidences that childhood brain tumors result in academic and social difficulties that compromise the quality of life of the patients. This study investigated the intellectual functioning of children between 7 to 15 years diagnosed with posterior fossa tumors and treated at CEHOPE - Recife / PE. 21 children were eligible - including 13 children with pilocytic astrocytoma (G1) who underwent only surgery resection, and eight children with medulloblastoma (G2) - submitted to surgical resection, chemotherapy and craniospinal radiotherapy. Participants were evaluated by the Wechsler Intelligence Scale for Children - WISC-III. Children of G1 scored better than children of G2. Inferential tools (Mann-Whitney Ü Test) identified significant diferences (p ≤ 0.05) between the Performance IQ (PIQ) and Processing Speed Index (PSI) as a function of treatment modality; Full Scale IQ (FSIQ), PIQ and PSI as a function of parental educational level; PIQ, FSIQ, IVP and Freedom from Distractibility (FDI) as a function of time between diagnosis and evaluation. These results showed the late and progressive impact of radiotherapy on white matter and information processing speed. Furthermore, children whose parents have higher educational level showed better intellectual performance, indicating the influence of xxii socio-cultural variables on cognitive development. The impact of cancer and its treatment on cognitive development and learning should not be underestimated. These results support the need to increase the understanding of such effects in order to propose therapeutic strategies which ensure that, in addition to the cure, the full development of children with this pathology

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Millon describes the normal personality by means of adaptation styles that are effective in normal environments and personality disorders such as unadapted operating styles. To operacionalize his theoretical model, Millon has built several instruments, including the Millon Clinical Multiaxial Inventory III (MCMI-III), wich consists of a self report inventory composed by 175 true or false response items, containing four verification scales, and others scales wich evaluates 14 personality patterns and 10 clinical syndromes. The Substance Dependence scale (T) is placed along with Clinical Syndromes scales. This research is justified by the lack of a Brazilian instrument to assess personality psychopathological aspects, and aims to translate and semantically adapt the MCMI-III to the Brazilian context, checking validity elements of the Substance Dependence scale, and developing a computer application for assisting the evaluation of assessment results. To this intent, 2.588 individuals data was collected, male and female, aged between 18 and 85 years, characterized as belonging to a clinical or non-clinical group, who took part in the survey via the internet or in person. Respondents completed the MCMI-III, a socio-demographic questionnaire and a subgroup also answered to the Goldberg General Health Questionnaire (GHQ). Besides descriptive statistics, we performed the analysis using the Student t test, principal components analysis and internal consistency. Despite difficulties related to translating very specific English terms, the assessment by judges, experts on Millon´s theory, and the back translation, attested the adequacy of the Brazilian version. Factorial analysis indicated the grouping of translated T scale items into three factors (social activities prejudice, lack of impulse control, and oppositional behavior), by presenting a single item on a fourth factor (apparently related to seeking pleasurable stimuli). The Cronbach alpha for this set of items was 0,82, indicating an acceptable scale reliability. The data analysis resulted in distinction of scores between clinical and non-clinical groups and between men and women; the relationship between high scores on the scale T and the other scales; scores of drug users according to the declared used substance; and the relationship between high scores on T and the verification of disorder or risk on GHQ mental health factor, indicating the instrument´s adequate sensistivity in identifying psychopathologies and the relationship between the different disorders or psychopathological personality patterns. Although further studies are necessary to develop the scores transformation factors, the computerized correction tool was adequate.

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The regeneration of bone defects with loss of substance remains as a therapeutic challenge in the medical field. There are basically four types of grafts: autologous, allogenic, xenogenic and isogenic. It is a consensus that autologous bone is the most suitable material for this purpose, but there are limitations to its use, especially the insufficient amount in the donor. Surveys show that the components of the extracellular matrix (ECM) are generally conserved between different species and are well tolerated even in xenogenic recipient. Thus, several studies have been conducted in the search for a replacement for autogenous bone scaffold using the technique of decellularization. To obtain these scaffolds, tissue must undergo a process of cell removal that causes minimal adverse effects on the composition, biological activity and mechanical integrity of the remaining extracellular matrix. There is not, however, a conformity among researchers about the best protocol for decellularization, since each of these treatments interfere differently in biochemical composition, ultrastructure and mechanical properties of the extracellular matrix, affecting the type of immune response to the material. Further down the arsenal of research involving decellularization bone tissue represents another obstacle to the arrival of a consensus protocol. The present study aimed to evaluate the influence of decellularization methods in the production of biological scaffolds from skeletal organs of mice, for their use for grafting. This was a laboratory study, sequenced in two distinct stages. In the first phase 12 mice hemi-calvariae were evaluated, divided into three groups (n = 4) and submitted to three different decellularization protocols (SDS [group I], trypsin [Group II], Triton X-100 [Group III]). We tried to identify the one that promotes most efficient cell removal, simultaneously to the best structural preservation of the bone extracellular matrix. Therefore, we performed quantitative analysis of the number of remaining cells and descriptive analysis of the scaffolds, made possible by microscopy. In the second stage, a study was conducted to evaluate the in vitro adhesion of mice bone marrow mesenchymal cells, cultured on these scaffolds, previously decellularized. Through manual counting of cells on scaffolds there was a complete cell removal in Group II, Group I showed a practically complete cell removal, and Group III displayed cell remains. The findings allowed us to observe a significant difference only between Groups II and III (p = 0.042). Better maintenance of the collagen structure was obtained with Triton X-100, whereas the decellularization with Trypsin was responsible for the major structural changes in the scaffolds. After culture, the adhesion of mesenchymal cells was only observed in specimens deccelularized with Trypsin. Due to the potential for total removal of cells and the ability to allow adherence of these, the protocol based on the use of Trypsin (Group II) was considered the most suitable for use in future experiments involving bone grafting decellularized scaffolds

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INTRODUÇÃO: A doença de Parkinson (DP) é caracterizada por uma degeneração progressiva seletiva de neurônios localizados na pars compacta da substância negra. Ela compõe-se por um conjunto de quatro sintomas motores: tremor, rigidez, bradicinesia e instabilidade postural. OBJETIVO: O estudo objetivou investigar os fatores relacionados à queda na percepção da qualidade de vida de indivíduos com DP. MATERIAIS E MÉTODOS: Participaram deste estudo 25 indivíduos com diagnóstico de doença de Parkinson, classificados entre os estágios um e cinco da escala de estadiamento de Hoen e Yahr, tendo a sua qualidade de vida avaliada segundo o Parkinson Disease Questionary-39 (PDQ-39). RESULTADOS: Os 25 indivíduos (12 homens e 13 mulheres) apresentaram idade média de 71,2 ± 8,5 anos, variando entre 53 a 85 anos, e tempo de evolução da doença de 6,54 ± 7,71, variando entre 1 e 39 anos de doença. Verificou-se que as piores percepções sobre a qualidade de vida estão relacionadas ao domínio mobilidade, com média de 55% de comprometimento, e ao domínio atividade de vida diária, com 52,78% de comprometimento. Ficou também constatada uma alta correlação entre o escore total do PDQ-39 com os domínios atividade de vida diária, bem-estar emocional e mobilidade. CONCLUSÕES: A partir dos resultados obtidos, é possível constatar que carências de origem motora associadas aos sinais e sintomas e às complicações secundárias da DP interferem negativamente sobre a percepção da qualidade de vida dos indivíduos.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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O ácido canárico 1 foi isolado das folhas de Rudgea jasminoides. A substância isolada é um derivado triterpênico do tipo seco-lupano e teve sua estrutura elucidada com base nos dados espectrais, principalmente em experimentos de RMN a 1D e 2D. O sitosterol, o estigmasterol e os ácidos ursólico e oleanólico também foram isolados.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Os opióides têm sido utilizados em Medicina Veterinária há vários anos como alternativa para o alívio da dor pós-operatória ou traumática. Atualmente, tem-se dado maior valor ao controle da dor nos animais, visando a oferecer melhores condições de recuperação ao paciente traumatizado ou recém-operado. A morfina foi o primeiro opióide usado em animais. Mais recentemente, a administração dessa substância, por via epidural, vem sendo empregada no controle da dor com resultados promissores. Assim, nesta revisão, abordam-se vários aspectos referentes aos efeitos e às indicações da administração epidural de opióides em cães.