Discopatia cervical no cão: tratamento cirúrgico através de fenestração ventral. Estudo retrospectivo (1986-1997)

Aproximadamente, 15% das discopatias em cães acometem a região cervical, sendo a dor o principal sinal clínico. Descreve-se a ocorrência de protrusão de disco cervical em 17 cães, agrupados segundo a raça, sexo, peso, idade, assim como a distribuição quanto à duração dos sintomas, acometimento dos discos intervertebrais (DIV), tempo de recuperação e porcentagem de sucesso, em relação à condição neurológica presente antes da cirurgia. A raça Dachshund representou 29,5% (n=5), cães sem raça definida, Poodle e Cocker Spaniel Inglês, 17,6% cada (n=9), Pinscher, 11,8% (n=2) e Dálmata, 5,9% (n=1). Destes, 58,8% eram machos (n=10) e 41,2%, fêmeas (n=7), com peso entre 2 e 29kg, e idade média igual a 5,8 anos. O quadro neurológico desses animais correspondia à dor e ataxia, com exceção de um cão Dálmata, 11 anos de idade, que apresentava tetraparesia. A duração dos sinais variou de 2 a 90 dias. Os DIV mais acometidos foram C2/3 (40%), C3/4 (25%), C4/5 (15%), C5/6 (10%) e C6/7 (10%), sendo que alguns animais apresentavam lesões múltiplas. O procedimento foi padrão para todos os animais, através da fenestração e curetagem de todos os DIV abordados pelo acesso ventral, ou seja, de C2/3 até C6/7, empregando-se para isso instrumental usado para remoção de tártaro dentário (curetas Gracey, curetas McCall, extratores de tártaro S.S.White e McCall). O tempo médio de recuperação foi de 9 a 38 dias, sendo que 100% deles recuperaram totalmente as funções neurológicas. Conclui-se que a fenestração ventral apresenta excelentes resultados no tratamento das discopatias cervicais, desde que bem selecionados os pacientes, inclusive, com respeito aos diagnósticos diferenciais.

Parâmetros espaço temporais da marcha e inter-relação com equilíbrio e força muscular isométrica de tornozelos em diabéticos com neuropatia periférica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Percepção da distância egocêntrica em idosos ativos e sedentários

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Alterações sensoriais e motoras associadas ao envelhecimento e controle postural de idosos

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

Análise comparativa de variáveis biomecânicas entre as mulheres idosas caidoras e não caidoras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo comparativo entre o bloqueio interescalênico do plexo branquial e o bloqueio seletivo dos nervos supraescapular e axilar nas cirurgias artroscópicas de ombro

Pós-graduação em Anestesiologia - FMB

Efeitos da atividade física no controle postural e capacidade funcional de idosos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Incapacidade física em pessoas afetadas pela hanseníase: estudo após alta medicamentosa

A incapacidade física é o principal problema da hanseníase. Apesar do sucesso da poliquimioterapia (PQT) no tratamento da doença, sabe-se que cerca de 25% a 50% dos pacientes podem ter algum dano do nervo e desenvolver incapacidades físicas, classificada pela Organização Mundial de Saúde (OMS) como grau de incapacidade física (GIF) 0 para sensibilidade normal, sem deformidades visíveis, 1 para a sensibilidade diminuída, sem alterações visíveis, ou 2 para deficiências visíveis / deformidade. De 2004 a 2010 o Brasil registrou 21,7% dos casos como sendo GIF 1 e 7% como GIF 2, enquanto que no Estado do Pará, 15,3% dos pacientes foram diagnosticados com GIF 1, e 5,1% com GIF 2 no momento do diagnóstico de hanseníase. A fim de investigar as incapacidades físicas em pacientes curados, examinamos as funções sensitivo-motoras de 517 pessoas afetadas pela hanseníase, notificados 2004 a 2010 em oito municípios hiperendêmicos da Amazônia brasileira, correlacionando os achados com aspectos epidemiológicos e sócio-econômico, e comparando com os dados encontrados no Sistema Nacional de Informação de Agravos de Notificação (SINAN). Adicionalmente, 2164 contatos intradomiciliares dos pacientes visitados foram avaliados clinicamente em busca de sinais e sintomas da doença. As visitas domiciliares dos pacientes constaram de avaliação clínica, avaliação neurológica simplificada e determinação do GIF, realização de entrevista sobre suas características demográficas e sócio-econômicas. O GIF 1 foi encontrado em 16,2% e DG 2 em 12,4% dos pacientes avaliados. Foi encontrada uma correlação estatisticamente significativa entre as formas multibacilares (MB) e o GIF 1 ou 2 (p <0,001), incapacidade física e o sexo masculino (p <0,001); incapacidade ocorreu em casos acima de 40 anos de idade (p <0,001). Mais da metade (50,5%) dos casos não tinha cicatriz de BCG, correlacionada com idades mais elevadas (p <0,001), casos MB (p <0,001), e com incapacidade (p <0,005). Por fim, embora SINAN informe apenas 5,6% de casos com GIF 2, encontramos 12,4% durante nossas visitas. Entre os contatos, foram diagnosticados 181 casos novos, 127 (70,2%) foram diagnosticados como multibacilares e 17,1% apresentaram incapacidade física, sendo 5,5% GIF 2. A ocorrência de deficiência física foi predominante em pacientes MB, homens,> 40 anos de idade e sem cicatriz de BCG, todos os fatores de risco importantes para o desenvolvimento de deficiência. As diferenças de GIF encontradas no SINAN e no nosso estudo sugerem piora das funções sensório-motor após a alta da PQT, indicando a importância do acompanhamento destes pacientes por anos depois de terminar o tratamento MDT. A alta taxa de detecção de casos novos diagnosticados neste estudo reflete o baixo índice de avaliação de contatos no estado do Pará (58,8%), perpetuando o diagnóstico tardio. Os achados clínicos sugerem a existência de prevalência oculta e alto índice de infecção subclínica na amostra estudada, indicando necessidade de avaliação clínica periódica.

O Caráter a priori das Estruturas Necessárias ao Conhecimento, Construídas segundo a Epistemologia Genética

In this paper we discuss the question of the a priori character of the necessary structures of knowledge according to Genetic Epistemology, focusing on the notion of space in particular. We establish some relations between Jean Piaget’s Genetic Epistemology and Immanuel Kant’s Critical Philosophy, discuss the notion of the a priori according to Kant in relation to the notion of space, and discuss the construction of the notion of space by the epistemic subject according to Genetic Epistemology, focusing on the Sensory-Motor Period. We conclude that, in Genetic Epistemology, space is still thought of as an a priori form of phenomena in the sense that the notion of space is what spatially organizes the data of perception, being the condition of perception. Furthermore, it is not directly abstracted from experience, but is constructed by the epistemic subject in its interaction with the environment, occurring with the structuring of the system of schemes of action. This analysis leads to the notion of the constructed a priori that, after its construction, has the characteristics of the a priori as conceived by Kant.

Avaliação do efeito do citral na dor neuropática e na inflamação

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

Efeitos da exposição gestacional a cádmio e dimetoato sobre o comportamento de ansiedade na prole de ratos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Multiple endocrine neoplasia type 1 presenting as refractory epilepsy and polyneuropathy - A case report

Hypoglycemia is a well recognized cause of acute symptomatic seizures. The fact that hypoglycemia can cause peripheral neuropathy is less appreciated. We describe a case of insulinoma associated peripheral neuropathy. A 17 year-old previously healthy man was referred for investigation of refractory epilepsy. A history of recurrent seizures, slowly progressive weakness of his feet and hands, and weight gain was obtained. Physical examination showed signs of a chronic sensory-motor polyneuropathy. He was diagnosed with insulinoma and primary hyperparathyroidism, characterizing multiple endocrine neoplasia, type 1 syndrome. Cases of insulinoma associated peripheral neuropathy are very rare. The more characteristic clinical picture appears to be distal weakness, worse in the intrinsic hand and feet muscles, and no or mild sensory signs. Peripheral nervous system symptoms may not completely resolve, despite removal of the cause of hyperinsulinism/hypoglycemia and full reversion of central nervous system symptoms. Mechanisms underlying hypoglycemic neuropathy are still poorly understood. (C) 2011 Elsevier B.V. All rights reserved.

Cannabidiol reduces host immune response and prevents cognitive impairments in Wistar rats submitted to pneumococcal meningitis

Pneumococcal meningitis is a life-threatening disease characterized by an acute infection affecting the pia matter, arachnoid and subarachnoid space. The intense inflammatory response is associated with a significant mortality rate and neurologic sequelae, such as, seizures, sensory-motor deficits and impairment of learning and memory. The aim of this study was to evaluate the effects of acute and extended administration of cannabidiol on pro-inflammatory cytokines and behavioral parameters in adult Wistar rats submitted to pneumococcal meningitis. Male Wistar rats underwent a cisterna magna tap and received either 10 mu l of sterile saline as a placebo or an equivalent volume of S. pneumoniae suspension. Rats subjected to meningitis were treated by intraperitoneal injection with cannabidiol (2.5, 5, or 10 mg/kg once or daily for 9 days after meningitis induction) or a placebo. Six hours after meningitis induction, the rats that received one dose were killed and the hippocampus and frontal cortex were obtained to assess cytokines/chemokine and brain-derived neurotrophic factor levels. On the 10th day, the rats were submitted to the inhibitory avoidance task. After the task, the animals were killed and samples from the hippocampus and frontal cortex were obtained. The extended administration of cannabidiol at different doses reduced the TNF-alpha level in frontal cortex. Prolonged treatment with canabidiol, 10 mg/kg, prevented memory impairment in rats with pneumococcal meningitis. Although descriptive, our results demonstrate that cannabidiol has anti-inflammatory effects in pneumococcal meningitis and prevents cognitive sequel. (C) 2012 Elsevier B.V. All rights reserved.

Functional coupling of sensorimotor and associative areas during a catching ball task: a qEEG coherence study

Abstract Background Catching an object is a complex movement that involves not only programming but also effective motor coordination. Such behavior is related to the activation and recruitment of cortical regions that participates in the sensorimotor integration process. This study aimed to elucidate the cortical mechanisms involved in anticipatory actions when performing a task of catching an object in free fall. Methods Quantitative electroencephalography (qEEG) was recorded using a 20-channel EEG system in 20 healthy right-handed participants performed the catching ball task. We used the EEG coherence analysis to investigate subdivisions of alpha (8-12 Hz) and beta (12-30 Hz) bands, which are related to cognitive processing and sensory-motor integration. Results Notwithstanding, we found the main effects for the factor block; for alpha-1, coherence decreased from the first to sixth block, and the opposite effect occurred for alpha-2 and beta-2, with coherence increasing along the blocks. Conclusion It was concluded that to perform successfully our task, which involved anticipatory processes (i.e. feedback mechanisms), subjects exhibited a great involvement of sensory-motor and associative areas, possibly due to organization of information to process visuospatial parameters and further catch the falling object.

Mathematical models of cognitive processes

The research activity carried out during the PhD course was focused on the development of mathematical models of some cognitive processes and their validation by means of data present in literature, with a double aim: i) to achieve a better interpretation and explanation of the great amount of data obtained on these processes from different methodologies (electrophysiological recordings on animals, neuropsychological, psychophysical and neuroimaging studies in humans), ii) to exploit model predictions and results to guide future research and experiments. In particular, the research activity has been focused on two different projects: 1) the first one concerns the development of neural oscillators networks, in order to investigate the mechanisms of synchronization of the neural oscillatory activity during cognitive processes, such as object recognition, memory, language, attention; 2) the second one concerns the mathematical modelling of multisensory integration processes (e.g. visual-acoustic), which occur in several cortical and subcortical regions (in particular in a subcortical structure named Superior Colliculus (SC)), and which are fundamental for orienting motor and attentive responses to external world stimuli. This activity has been realized in collaboration with the Center for Studies and Researches in Cognitive Neuroscience of the University of Bologna (in Cesena) and the Department of Neurobiology and Anatomy of the Wake Forest University School of Medicine (NC, USA). PART 1. Objects representation in a number of cognitive functions, like perception and recognition, foresees distribute processes in different cortical areas. One of the main neurophysiological question concerns how the correlation between these disparate areas is realized, in order to succeed in grouping together the characteristics of the same object (binding problem) and in maintaining segregated the properties belonging to different objects simultaneously present (segmentation problem). Different theories have been proposed to address these questions (Barlow, 1972). One of the most influential theory is the so called “assembly coding”, postulated by Singer (2003), according to which 1) an object is well described by a few fundamental properties, processing in different and distributed cortical areas; 2) the recognition of the object would be realized by means of the simultaneously activation of the cortical areas representing its different features; 3) groups of properties belonging to different objects would be kept separated in the time domain. In Chapter 1.1 and in Chapter 1.2 we present two neural network models for object recognition, based on the “assembly coding” hypothesis. These models are networks of Wilson-Cowan oscillators which exploit: i) two high-level “Gestalt Rules” (the similarity and previous knowledge rules), to realize the functional link between elements of different cortical areas representing properties of the same object (binding problem); 2) the synchronization of the neural oscillatory activity in the γ-band (30-100Hz), to segregate in time the representations of different objects simultaneously present (segmentation problem). These models are able to recognize and reconstruct multiple simultaneous external objects, even in difficult case (some wrong or lacking features, shared features, superimposed noise). In Chapter 1.3 the previous models are extended to realize a semantic memory, in which sensory-motor representations of objects are linked with words. To this aim, the network, previously developed, devoted to the representation of objects as a collection of sensory-motor features, is reciprocally linked with a second network devoted to the representation of words (lexical network) Synapses linking the two networks are trained via a time-dependent Hebbian rule, during a training period in which individual objects are presented together with the corresponding words. Simulation results demonstrate that, during the retrieval phase, the network can deal with the simultaneous presence of objects (from sensory-motor inputs) and words (from linguistic inputs), can correctly associate objects with words and segment objects even in the presence of incomplete information. Moreover, the network can realize some semantic links among words representing objects with some shared features. These results support the idea that semantic memory can be described as an integrated process, whose content is retrieved by the co-activation of different multimodal regions. In perspective, extended versions of this model may be used to test conceptual theories, and to provide a quantitative assessment of existing data (for instance concerning patients with neural deficits). PART 2. The ability of the brain to integrate information from different sensory channels is fundamental to perception of the external world (Stein et al, 1993). It is well documented that a number of extraprimary areas have neurons capable of such a task; one of the best known of these is the superior colliculus (SC). This midbrain structure receives auditory, visual and somatosensory inputs from different subcortical and cortical areas, and is involved in the control of orientation to external events (Wallace et al, 1993). SC neurons respond to each of these sensory inputs separately, but is also capable of integrating them (Stein et al, 1993) so that the response to the combined multisensory stimuli is greater than that to the individual component stimuli (enhancement). This enhancement is proportionately greater if the modality-specific paired stimuli are weaker (the principle of inverse effectiveness). Several studies have shown that the capability of SC neurons to engage in multisensory integration requires inputs from cortex; primarily the anterior ectosylvian sulcus (AES), but also the rostral lateral suprasylvian sulcus (rLS). If these cortical inputs are deactivated the response of SC neurons to cross-modal stimulation is no different from that evoked by the most effective of its individual component stimuli (Jiang et al 2001). This phenomenon can be better understood through mathematical models. The use of mathematical models and neural networks can place the mass of data that has been accumulated about this phenomenon and its underlying circuitry into a coherent theoretical structure. In Chapter 2.1 a simple neural network model of this structure is presented; this model is able to reproduce a large number of SC behaviours like multisensory enhancement, multisensory and unisensory depression, inverse effectiveness. In Chapter 2.2 this model was improved by incorporating more neurophysiological knowledge about the neural circuitry underlying SC multisensory integration, in order to suggest possible physiological mechanisms through which it is effected. This endeavour was realized in collaboration with Professor B.E. Stein and Doctor B. Rowland during the 6 months-period spent at the Department of Neurobiology and Anatomy of the Wake Forest University School of Medicine (NC, USA), within the Marco Polo Project. The model includes four distinct unisensory areas that are devoted to a topological representation of external stimuli. Two of them represent subregions of the AES (i.e., FAES, an auditory area, and AEV, a visual area) and send descending inputs to the ipsilateral SC; the other two represent subcortical areas (one auditory and one visual) projecting ascending inputs to the same SC. Different competitive mechanisms, realized by means of population of interneurons, are used in the model to reproduce the different behaviour of SC neurons in conditions of cortical activation and deactivation. The model, with a single set of parameters, is able to mimic the behaviour of SC multisensory neurons in response to very different stimulus conditions (multisensory enhancement, inverse effectiveness, within- and cross-modal suppression of spatially disparate stimuli), with cortex functional and cortex deactivated, and with a particular type of membrane receptors (NMDA receptors) active or inhibited. All these results agree with the data reported in Jiang et al. (2001) and in Binns and Salt (1996). The model suggests that non-linearities in neural responses and synaptic (excitatory and inhibitory) connections can explain the fundamental aspects of multisensory integration, and provides a biologically plausible hypothesis about the underlying circuitry.