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Purpose To present a model to reproduce the clinical condition, in order to better understand the pathophysiology of neurological impairment related to intoxication. Methods Twenty-five Wistar rats were used and divided into five groups: Shaw group (WHI), water gavage group (WGV), star fruit gavage group (SGV), nephropathic group with water gavage (NPW), nephropathic group with star fruit gavage (NPS).Nephropathic groups were submitted to surgery, developing nephropathy. After surgery, they received preestablished gavage with star fruit juice or water. The electroencephalographic records were evaluated in the experimental nephropathic group that received gavage of star fruit juice. Results To assess the induction of neurotoxicity using electroencephalographic data, the NPS group demonstrated the presence of epileptic seizures associated with star fruit intoxication. Conclusions The experimental model herein presented was adequate to reproduce the clinical condition experienced by nephropathic patients who ingest star fruit juice, establishing, thus, an experimental model utterly important for the study of the neurological toxicity process.

Periodontal disease (PD) is an infectious-inflammatory oral disease that is highly prevalent among adolescence and adulthood and can lead to chronic orofacial pain and be associated with anxiety, stress and depression. This study aimed to identify anxiety-like behaviors in the ligature-induced murine preclinical model of PD in different phases of the disease (i.e., acute vs. chronic). Also, we investigated orofacial mechanical allodynia thresholds and superficial cortical plasticity along the orofacial motor cortex in both disease phases. To this aim, 25 male Wistar rats were randomly allocated in acute (14 days) or chronic (28 days) ligature-induced-PD groups and further divided into active-PD or sham-PD. Anxiety-like behavior was evaluated using the elevated plus maze, mechanical allodynia assessed using the von Frey filaments test and superficial motor cortex mapping was performed with electrical transdural stimulation. We observed increased anxiety-like behavior in active-PD animals in the acute phase, characterized by decreased number of entries into the open arm extremities [t(1,7) = 2.42, p = 0.04], and reduced time spent in the open arms [t(1,7) = 3.56, p = 0.01] and in the open arm extremities [t(1,7) = 2.75, p = 0.03]. There was also a reduction in the mechanical allodynia threshold in all active-PD animals [Acute: t(1,7) = 8.81, p < 0.001; Chronic: t(1,6) = 60.0, p < 0.001], that was positively correlated with anxiety-like behaviors in the acute group. No differences were observed in motor cortex mapping. Thus, our findings show the presence of anxiety-like behaviors in the acute phase of PD making this a suitable model to study the impact of anxiety in treatment response and treatment efficacy.

Purpose Studies have demonstrated that star fruit consumption by nephropathic patients triggers severe neurotoxic effects that can lead to convulsions or even death. Brain areas likely susceptible to star fruit poisoning have not been investigated. The objective of the present study was to map possible epileptogenic areas susceptible to star fruit intoxication in nephropathic rats. Methods The study analyzed 25 rats (5 groups). Rats in the experimental group underwent bilateral ureteral obstruction surgery and orogastric gavages with star fruit juice. An electroencephalogram was used to confirm convulsive seizures. Urea and creatinine levels were used to confirm the uremia model. Immunohistochemical analysis was used to map cells with c-Fos protein (c-Fos+ cells) to identify brain areas with increased neuronal activity. Control groups included non-nephropathic and nephropathic rats that did not receive star fruit. Results A statistically significant increase (p

Cortical electrical stimulation (CES) has shown to be an effective therapeutic alternative for neuropathic pain refractory to pharmacological treatment. The primary motor cortex(M1) was the main cortical target used in the vast majority of both invasive and non-invasive studies. Despite positive results M1-based approaches still fail to relieve pain in a significant proportion of individuals. It has been advocated that the direct stimulation of cortical areas directly implicated in the central integration of pain could increase the efficacy of analgesic brain stimulation. Here, we evaluated the behavioral effects of electrical stimulation of the insular cortex (ESI) on pain sensitivity in an experimental rat model of peripheral neuropathy, and have described the pathways involved. Animals underwent chronic constriction of the sciatic nerve in the right hind limb and had concentric electrodes implanted in the posterior dysranular insular cortex. Mechanical nociception responses were evaluated before and at the end of a 15-min session of ESI (60Hz, 210μs, 1V). ESI reversed mechanical hypersensitivity in the paw contralateral to the brain hemisphere stimulated, without inducing motor impairment in the open-field test. Pharmacological blockade of μ-opioid (MOR) or type 1-cannabinoid receptors (CB1R) abolished ESI-induced antinociceptive effects. Evaluation of CB1R and MOR spatial expression demonstrated differential modulation of CB1R and MOR in the periaqueductal gray matter (PAG) of ESI-treated rats in sub-areas involved in pain processing/modulation. These results indicate that ESI induces antinociception by functionally modulating opioid and cannabinoid systems in the PAG pain circuitry in rats with experimentally induced neuropathic pain.

OBJETIVO: Pacientes com lesão medular cervical alta em geral são dependentes de ventilação mecânica, que, embora salve vidas, está associada a complicações e redução da expectativa de vida devido a infecções respiratórias. A estimulação do diafragma por marca-passo, às vezes chamada de ventilação elétrica, induz a inspiração por estimulação dos músculos inspiratórios. Nosso objetivo foi destacar as indicações e alguns aspectos da técnica cirúrgica empregada no implante laparoscópico dos eletrodos, assim como descrever cinco casos de pacientes tetraplégicos submetidos à técnica. MÉTODOS: A seleção dos pacientes envolveu estudos de condução do nervo frênico por via transcutânea para determinar se os nervos estavam preservados. A abordagem cirúrgica foi laparoscopia clássica, com quatro trocartes. A técnica foi iniciada com o mapeamento elétrico para encontrar os "pontos motores" (pontos de contração máxima do diafragma). Se o mapeamento era bem-sucedido, dois eletrodos eram implantados na face abdominal de cada lado do diafragma para estimular ramos do nervo frênico. RESULTADOS: Dos cinco pacientes, três e um, respectivamente, eram capazes de respirar somente com o uso do marca-passo por períodos superiores a 24 e 6 h, enquanto um não era capaz. CONCLUSÕES: Embora seja necessário um acompanhamento mais longo para chegar a conclusões definitivas, os resultados iniciais são promissores, pois, no momento, a maioria dos nossos pacientes pode permanecer sem ventilação mecânica por longos períodos de tempo. OBJECTIVE: Patients with high cervical spinal cord injury are usually dependent on mechanical ventilation support, which, albeit life saving, is associated with complications and decreased life expectancy because of respiratory infections. Diaphragm pacing stimulation (DPS), sometimes referred to as electric ventilation, induces inhalation by stimulating the inspiratory muscles. Our objective was to highlight the indications for and some aspects of the surgical technique employed in the laparoscopic insertion of the DPS electrodes, as well as to describe five cases of tetraplegic patients submitted to the technique. METHODS: Patient selection involved transcutaneous phrenic nerve studies in order to determine whether the phrenic nerves were preserved. The surgical approach was traditional laparoscopy, with four ports. The initial step was electrical mapping in order to locate the "motor points" (the points at which stimulation would cause maximal contraction of the diaphragm). If the diaphragm mapping was successful, four electrodes were implanted into the abdominal surface of the diaphragm, two on each side, to stimulate the branches of the phrenic nerve. RESULTS: Of the five patients, three could breathe using DPS alone for more than 24 h, one could do so for more than 6 h, and one could not do so at all. CONCLUSIONS: Although a longer follow-up period is needed in order to reach definitive conclusions, the initial results have been promising. At this writing, most of our patients have been able to remain ventilator-free for long periods of time.

Learning medicine is a difficult process to undertake, partially due to the complexity of the subject and limitations of traditional methods of teaching (lectures, textbooks, laboratory and anatomical dissections). These resources have been effective for decades, even though presenting intrinsic drawbacks. Textbooks are non-interactive education tools and do not provide any three dimensional experience. Cadaver dissection is an invaluable aid to learn anatomy. It provides an immersive, interactive experience allied with an inimitable tactile feedback. However, it has several limitations, including availability of specimens, costs and a substantial time commitment. Computer based virtual reality methods may overcome these drawbacks and provide interesting alternatives for medical training. Technological advances have generated great expectations for the use of computer-based virtual reality technologies in medical education, mainly anatomy and surgery. However, these Virtual Reality tools for general medical education are expensive due to the equipment necessary to create highly detailed, immersive three-dimensional image environments with real time friendly user interactivity. The concepts of Virtual Reality methods that generate immersive environments, as well as those that create simulated objects with interactive viewing features may be contemplated by the QuickTimeTM which is one of the technologies that can be successfully used for interactive, photorealistic displaying of medical images (radiological, anatomical and histological) and interaction on current generation of personal computers at a low and accessible cost. In this paper, the authors provide an overview of the Quick Time Virtual Reality methods aiming to introduce them to medical educators and illustrate their application on medical training.

Objective: Delayed ischemic preconditioning has demonstrated neuroprotective effects in spinal cord ischemia. We investigated the effects of immediate ischemic preconditioning based on somatosensory evoked potentials monitoring in a model of spinal cord injury due descending thoracic aorta occlusion in dogs. Methods: Twenty-one dogs were submitted to spinal cord ischemia induced by descending thoracic aorta crossclamping for 45 min. Control group underwent only the aortic cross-clamping (nZ7), group A underwent one cycle of ischemic preconditioning (nZ7) and group B underwent three equal cycles of ischemic preconditioning (nZ7), immediately before the aortic cross-clamping. Ischemic preconditioning cycles were determined by somatosensory evoked potentials monitoring. Neurologic evaluation was performed according to the Tarlov score at 72 h of follow-up. The animals were then sacrificed and the spinal cord harvested for histopathology. Results: Aortic pressures before and after the occluded segment were similar in the three groups. Ischemic preconditioning periods corresponded to a mean ischemic time of 3G1 min and a mean recovery time of 7G2 min. Severe paraplegia was observed in three animals in Control group, in four in group A and in none in group B. Tarlov scores of group B were significantly better in comparison to the Control group (PZ0.036). Histopathologic examination showed severe neuronal necrosis in the thoracic and lumbar gray matter in animals who presented paraplegia. Conclusions: Immediate repetitive ischemic preconditioning based on somatosensory evoked potentials monitoring seems to protect spinal cord during descending aorta cross-clamping, reducing paraplegia incidence. Q 2005 Elsevier B.V. All rights reserved.

This paper describes the detection of preictal bursting using wavelet transform application and cross-correlation analysis. The wavelet transform is applied to data reduction and signal pre-processing. The extracted features provide simplified signals to process by means of the cross-correlation technique. The algorithm has been tested with a set of preictal data, interictal data and spontaneous crises, to determinate its sensitivity and its specificity (False Prediction Rate). The seizure occurrence period and the seizure prediction horizon are also calculated. The algorithm's merits are: 1) high sensitivity and 2) easy implementation.

Aims: To investigate whether anterior thalamic nucleus (AN) lesions are protective against spontaneous recurrent seizures in the chronic phase of the pilocarpine model of epilepsy. Methods: Two groups of rats were treated with bilateral AN radiofrequency thalamotomies or sham surgery 2 weeks after pilocarpine-induced status epilepticus. After the lesions, animals were videotaped from the 2nd to the 8th week after status epilepticus (total 180 h). Results: During the 6 weeks of observation, no differences in the frequency of spontaneous seizures were found between animals that had bilateral AN lesions (n = 26; 3.1 ± 0.6 seizures per animal) and controls (n = 25; 3.0 ± 0.6 seizures per animal; p = 0.8). Conclusions: We conclude that AN thalamotomies were not effective in reducing the frequency of seizures during the chronic phase of the pilocarpine model of epilepsy.

Epidural motor cortex stimulation (MCS) has been used for treating patients with neuropathic pain resistant to other therapeutic approaches. Experimental evidence suggests that the motor cortex is also involved in the modulation of normal nociceptive response, but the underlying mechanisms of pain control have not been clarified yet. The aim of this study was to investigate the effects of epidural electrical MCS on the nociceptive threshold of naive rats. Electrodes were placed on epidural motor cortex, over the hind paw area, according to the functional mapping accomplished in this study. Nociceptive threshold and general activity were evaluated under 15-min electrical stimulating sessions. When rats were evaluated by the paw pressure test, MCS induced selective antinociception in the paw contralateral to the stimulated cortex, but no changes were noticed in the ipsilateral paw. When the nociceptive test was repeated 15 min after cessation of electrical stimulation, the nociceptive threshold returned to basal levels. On the other hand, no changes in the nociceptive threshold were observed in rats evaluated by the tail-flick test. Additionally, no behavioral or motor impairment were noticed in the course of stimulation session at the open-field test. Stimulation of posterior parietal or somatosensory cortices did not elicit any changes in the general activity or nociceptive response. Opioid receptors blockade by naloxone abolished the increase in nociceptive threshold induced by MCS. Data shown herein demonstrate that epidural electrical MCS elicits a substantial and selective antinociceptive effect, which is mediated by opioids.

An 18-year-old boy with refractory epilepsy and aggressiveness associated to a hypothalamic hamartoma was submitted to a stereotactically guided lesion by thermocoagulation. The target was based on magnetic resonance (MR) images merged with computed tomography scan images taken on the day of surgery while patient was on a stereotactic frame. In order to reveal structures not discernible in MR images, the Schaltenbrand digital brain atlas was merged onto the patient's images. Target and trajectory of the depth electrode were chosen based on three-dimensional imaging reconstructions. A surgical plan was devised to disconnect the hypothalamic hamartoma from the hypothalamus, medial forebrain bundle, fasciculus princeps, and dorsal longitudinal fasciculus. Our target was placed at the inferior portion of the posterolateral component of the hamartoma, bordering the normal hypothalamus. The patient evolved with marked lessening of aggressiveness. Seizure frequency was reduced from several seizures per day to less than one tonic-clonic seizure during sleep per month and only two episodes suggestive of partial complex seizures during daytime. These results have remained consistent over a 24-month postoperative follow-up. Functional neuroanatomy of hypothalamic connections involved in seizure propagation and aggressive behavior was reviewed.

OBJETIVOS: Avaliar a eficácia do pré-condicionamento isquêmico (PI) agudo, guiado por potenciais evocados somatossensoriais (PESS), como método de proteção medular em cães e analisar o valor dos PESS na monitorização da função medular. MÉTODOS: Foram utilizados 28 cães submetidos à isquemia medular obtida pelo pinçamento da aorta torácica descendente. No grupo C45, o tempo de oclusão aórtica foi de 45 min (n = 7); no grupo PI45, os cães foram submetidos ao PI antes do pinçamento aórtico por 45 min (n = 7). No grupo C60, os cães foram submetidos a 60 min de oclusão aórtica (n = 7) e no grupo PI60, os cães foram submetidos ao PI, seguido pelo pinçamento aórtico por 60 min. Os ciclos de PI foram determinados pelas alterações dos PESS. RESULTADOS: Os índices de Tarlov dos grupos pré-condicionados foram significativamente melhores que os dos grupos de controle (p = 0,005). Observou-se paraplegia em três cães do C45 e em seis do C60, enquanto todos os cães do PI45 permaneceram neurologicamente normais, assim como quatro do grupo PI60. Houve correlação entre o tempo de recuperação dos PESS após a reperfusão aórtica e o estado neurológico pós-operatório (p = 0,011), com sensibilidade e especificidade de 0,75 e 0,83, respectivamente. CONCLUSÃO: O PI agudo repetitivo, baseado na monitorização do PESS, induziu proteção à isquemia medular causada pelo pinçamento aórtico prolongado. A monitorização do PESS parece ser um bom método de detecção precoce do comprometimento isquêmico medular. OBJECTIVES: To evaluate the effectiveness of acute ischemic preconditioning (IP), based on somatosensory evoked potentials (SSEP) monitoring, as a method of spinal cord protection and to asses SSEP importance in spinal cord neuromonitoring. METHODS: Twenty-eight dogs were submitted to spinal cord ischemic injury attained by descending thoracic aorta cross-clamping. In the C45 group, the aortic cross-clamping time was 45 min (n=7); in the IP45 group, the dogs were submitted to IP before the aortic cross-clamping for 45 min (n=7). In the C60 group, the dogs were submitted to 60 min of aortic cross-clamping (n=7), as in the IP60 group that was previously submitted to IP. The IP cycles were determined based on SSEP changes. RESULTS: Tarlov scores of the IP groups were significantly better than those of the controls (p = 0.005). Paraplegia was observed in 3 dogs from C45 and in 6 from C60 group, although all dogs from IP45 group were neurologically normal, as 4 dogs from IP60. There was a significant correlation between SSEP recovery time until one hour of aortic reperfusion and the neurological status (p = 0.011), showing sensitivity of 75% and specificity of 83%. CONCLUSION: Repetitive acute IP based on SSEP is a protection factor during spinal cord ischemia, decreasing paraplegia incidence. SSEP monitoring seems to be a good neurological injury assessment method during surgical procedures that involve spinal cord ischemia.

We have recently obtained evidence for complex multifocal, individually variable generators of slow cortical potentials, elicited during performance of visual tasks involving expecting attention, comparison and memory [Basile, L.F.H., Ballester, G., Castro, C.C., and Gattaz, W.F., 2002. Multifocal slow potential generators revealed by high-resolution EEG and current density reconstruction. Int. J. Psychophysiol., 45 (3), 227–240; Basile, L.F.H, Baldo, M.V., Castro, C.C., and Gattaz, W.F. 2003. The generators of slow potentials obtained during verbal, pictorial and spatial tasks. Int. J. Psychophysiol., 48, 55–65]. The cue–target aspect of traditional paradigms for attention studies is equivalent to ‘warning S1’–‘imperative S2’ in slow potential designs. We simplified Posner's spatial cueing task [Posner, M.I. 1980. Orienting of attention.Q. J. Exp. Psychol. Feb;32 (1), 3–25; Posner, M.I., Snyder, C.R., Davidson, B.J. 1980. Attention and the detection of signals. J Exp Psychol. Jun; 109 (2), 160–174] to temporal cuing only, by using visual cues to indicate the mere presence, on a known central position, of the eventual target (17 ms duration, ± 0.3° grey circle). We recorded slow potentials on 12 healthy subjects, by 124-channel EEG system (Neuroscan Inc.), and modeled their generators using current density reconstruction (CDR) by Lp 1.2 norm minimization (“Curry V4.6”, Neurosoft Inc.) applied to the target onset time. MRIs were obtained for each subject for constraining source models to individual brain anatomy. Average slow potentials were computed from above 60 artifact-free EEG-epochs (ISI = 1.6 s, average ITI = 2.5 s). We tabulated individual cortical current distributions by cytoarchitectonic area of Brodmann, after scaling into negligible, low, moderate and strong local density, based on percentile bands with respect to absolute maximum current. Despite the task's simplicity, the main result was individual variability and complexity in both scalp voltage and cortical current distributions. As observed in our previous studies, there was strong intersubject variability in the exact distribution of task-related cortical activity. Only parietal area 7 bilaterally was non-negligibly active in all subjects (currents above 10% maximum). As opposed to drawing conclusions based on group averaged data, we propose that activity by cytoarchitectonic area be ranked and statistically analysed only after being scaled on each individual. Based on the present results, the concept of a universal attention-related set of cortical areas if restricted to common areas across subjects is challenged, since even area 7 may no longer be common when the sample size becomes larger. We discuss the fact that group averaging may de-emphasize weakly but consistently active areas, and emphasize strongly but inconsistently active ones.

Objective The thalamus is thought to play an important role in secondary generalization of seizures. The aim of the present study was to investigate the influence of anterior thalamic nucleus lesions and high-frequency stimulation in the pilocarpine model of secondarily generalized seizures in rats. Methods Adult Wistar rats underwent unilateral (n = 7) or bilateral anterior nucleus thalamotomies (n = 10), or unilateral (n = 4) or bilateral (n = 9) anterior thalamic nucleus stimulation through implanted electrodes. Control animals (n = 9) received bilateral implants but no stimulation. Seven days after these procedures, animals were provided pilocarpine (320 mg/kg intraperitoneally) to induce seizures and status epilepticus (SE). Electrographic recordings from hippocampal and cortical electrodes were evaluated, and ictal behavior was assessed. Results In the control group, 67% of the animals developed SE 15.3 +/- 8.8 minutes after pilocarpine administration. Neither unilateral anterior nucleus lesions nor stimulation significantly reduced the propensity or latency for developing seizures and SE. Bilateral thalamic stimulation did not prevent SE (observed in 56% of the animals), but it significantly prolonged the latency to its development (48.4 +/- 17.7 min, P = 0.02). Strikingly, no animal with bilateral anterior nucleus thalamotomies developed seizures or SE with pilocarpine. Conclusion Bilateral anterior thalamic nuclear complex stimulation and thalamotomies were protective against SE induced by pilocarpine.

We analyzed the electrical generators of CNV-type potentials obtained during a visual paired-associates memory task, using Lp norm minimization constrained by individual cortical anatomy. The task that we designed maximized the chances of verifying prefrontal cortex activity, by combining the anticipation of interesting, relatively arousing stimuli with the uncertain expectation based on memory recall. We tested a set of topographical hypotheses on the relation between activity in particular prefrontal domains and task conditions. The task consisted in two types of blocks: 1) memorization, when pairs of words, or abstract figures or positions on the screen were separated in time by 2,5 seconds @l-S2 stimuli); 2) execution with feedback for each trial, when subjects had to decide whether the upcoming pair (S2) of a given stimulus (Sl), just seen in the previous memorization block, formed or not a category match. Sl remained on the screen until a button press indicated the subject’s decision. Two and a half seconds after button press, S2 was presented, and 2,5 seconds after S2 onset, the feedback stimulus (S3) was presented. An interesting, relatively arousing visual stimulus indicated correct and an unpleasant sound indicated incorrect performance. We recorded the EEG using a 123-channel montage in 19 healthy subjects We used a realistic, three compartments model of the head, based on segmentation of individual TZweighed MRI sets and approximation by few milimeter side triangles. Approximately 20.000 points distributed over the cortical surface supported possible model equivalent current dipoles. The average slow potentials were then transformed into signal-to-noise ratios, and the intracranial electrical generators modeled as distributed current sources. For solving the inverse problem (finding the best fitting current distributions that explain the surface data), we applied a minimization algorithm to the Lp (p= 1.2) norms of data and model terms. The generators of the feedback anticipation CNVs consisted in a set of cortical association areas, including prefrontal Brodmann areas 9 and 10 in all subjects. We also obtained preliminary evidence, by analyzing potentials averaged across subjects, for task-specific (verbal, spatial and pictorial) topography of the memorization CNVs. The generators of such group average potentials were also a collection of cortical areas, with some areas appearing to be specifically active during the spatial subtask (left areas 9,10, lateral 6,5,39 and right 19), as opposed to some areas active during the verbal subtask (right 9,22 and 7). The pictorial subtask seemed to combine activity from the other two subtasks. We propose the use of current density reconstruction of the generators of slow potentials as a method for evaluating the functional integrity of cortical association areas in neuropsychiatric clinical conditions. We have started to use such method in a group of schizophrenic patients, and found preliminary evidence, using group averaged potentials, for important abnormalities in signalto-noise ratios and in the topography of all CNVs in the schizophrenic group. The global field power of the memorization CNVs was enhanced in the three subtasks. Finally, preliminary source reconstruction, by the projection of group potentials onto representative head models, indicated a larger degree of generator dispersion in the group of patients.

p. 1-6 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-02-18T14:17:09Z No. of bitstreams: 1 Abrahão F Batista.pdf: 280008 bytes, checksum: e084a734cde588dbe3c33d065e883844 (MD5) Approved for entry into archive by Flávia Ferreira (flaviaccf@yahoo.com.br) on 2014-11-28T16:03:05Z (GMT) No. of bitstreams: 1 Abrahão F Batista.pdf: 280008 bytes, checksum: e084a734cde588dbe3c33d065e883844 (MD5) Made available in DSpace on 2014-11-28T16:03:05Z (GMT). No. of bitstreams: 1 Abrahão F Batista.pdf: 280008 bytes, checksum: e084a734cde588dbe3c33d065e883844 (MD5) Previous issue date: 2011 Backgroud It has been shown that different symptoms or symptom combinations of neuropathic pain (NeP) may correspond to different mechanistic backgrounds and respond differently to treatment. The Neuropathic Pain Symptom Inventory (NPSI) is able to detect distinct clusters of symptoms (i.e. dimensions) with a putative common mechanistic background. The present study described the psychometric validation of the Portuguese version (PV) of the NPSI. Methods Patients were seen in two consecutive visits, three to four weeks apart. They were asked to: (i) rate their mean pain intensity in the last 24 hours on an 11-point (0-10) numerical scale; (ii) complete the PV-NPSI; (iii) provide the list of pain medications and doses currently in use. VAS and Global Impression of Change (GIC) were filled out in the second visit. Results PV-NPSI underwent test-retest reliability, factor analysis, analysis of sensitivity to changes between both visits. The PV-NPSI was reliable in this setting, with a good intra-class correlation for all items. The factorial analysis showed that the PV-NPSI inventory assessed different components of neuropathic pain. Five different factors were found. The PV-NPSI was adequate to evaluate patients with neuropathic pain and to detect clusters of NeP symptoms. Conclusions The psychometric properties of the PV-NPSI rendered it adequate to evaluate patients with both central and peripheral neuropathic pain syndromes and to detect clusters of NeP symptoms.

Observa-se nos tempos atuais um crescente interesse e demanda por novas tecnologias de sensoriamento e interação. A monitoração, com o objetivo de reconhecimento de movimentos humanos, permite oferecer serviços personalizados em diferentes áreas, dentre elas a área de cuidados médicos. Essa monitoração pode ser realizada por meio de diferentes técnicas como o uso de câmeras de vídeo, instrumentação do ambiente onde o indivíduo habita, ou pelo uso de dispositivos pessoais acoplados ao corpo. Os dispositivos acoplados ao corpo apresentam vantagens como baixo custo, uso confortável, além de muitas vezes serem despercebidos pelo usuário, diminuindo a sensação de invasão de privacidade durante a monitoração. Além disso, o dispositivo sensor pode ser facilmente acoplado ao corpo pelo próprio usuário, tornando o seu uso efetivo. Deste modo, este trabalho apresenta o desenvolvimento de um sistema que emprega técnicas de inteligência computacional e um acelerômetro facilmente acoplado ao punho do usuário para efetuar, de maneira confortável e não invasiva, o reconhecimento de movimentos básicos da rotina de uma pessoa. Aplicando máquinas de vetores de suporte para classificar os sinais e a razão discriminante de Fisher para efetuar a seleção das características mais significativas, o sistema apresentou uma taxa de sucesso em torno de 93% no reconhecimento de movimentos básicos efetuados por indivíduos monitorados. O sistema apresenta potencialidade para ser integrado a um hardware embarcado de baixo custo, responsável pelo gerenciamento da aquisição dos dados e pelo encaminhamento das informações a um sistema de monitoramento ou armazenamento. As informações providas por este sistema podem ser destinadas à promoção da saúde e bem estar do indivíduo, bem como utilizadas em diagnósticos ou monitoramento remoto de pacientes em um ambiente de vida assistida. Nowadays it is observed a growing interest and demand for new sensing technologies and interaction. Monitoring with the objective of recognizing human movements, allows us to offer personalized services in different areas, among them healthcare. This monitoring can be performed through the use of different techniques such as the use of video cameras, living environment instrumentation, or the use of personal devices attached to the body, also known as wearable devices. These wearable devices have some advantages such as low cost, comfortable to use, and are often unnoticed by the user, reducing the feeling of privacy invasion during the monitoring. In addition, the sensing device can be easily attached to the body by the user itself, making its use effective. Thus, this work presents the development of a system that uses computational intelligence techniques and an accelerometer which is easily attached to the users wrist to perform, in a comfortable and non-invasive manner, the recognition of basic movements of a persons routine. By applying support vector machines to classify the signals and Fishers discriminant ratio to select the most significant features, the system has shown a success rate of 93% in the recognition of basic movements performed by monitored individuals. The system has the potential to be integrated into a low-cost embedded hardware, which is responsible for managing the data acquisition and routing the movement data to a remote monitoring system or storage. The information provided by the system can be designed to promote the health and wellness of the individual, as well used in diagnostics or remote patient monitoring in an ambient assisted living (AAL).

Este trabalho apresenta os resultados obtidos na elaboração de dois modelos para o fenômeno da dor utilizando-se redes neurais artificiais, de forma a simular computacionalmente as prováveis respostas de um indivíduo na presença de dor. Os modelos são fundamentados na Teoria de Controle da Comporta de dor, onde são analisados os principais componentes envolvidos na percepção/inibição da dor, bem como o funcionamento dos mecanismos biológicos e cognitivos participantes do processo. A escolha do tipo de rede neural é feita a partir das observações realizadas, considerando-se também o número de fatores envolvidos e o comportamento esperado frente a cada conjunto de entrada. O método de treinamento das redes neurais baseia-se no algoritmo de retropropagação. O foco do processamento da rede é responder adequadamente, considerando-se a influência das entradas envolvidas, a eventos posteriores à ocorrência de uma lesão gerando um sinal de alerta a ser utilizado como uma resposta natural do organismo a este dano tecidual. O desempenho de cada modelo é avaliado comparando-se as saídas obtidas com aquelas esperadas para cada padrão de entrada. This work presents the results of two models that were developed to describe the phenomenon of pain using Artificial Neural Networks, with the final goal to simulate computationally possible answers of an individual in the presence of pain. The models are based on The Gate Control Theory, where the main components involved in the perception/inhibition of pain were analysed, as well as the operation of the biological and cognitive mechanisms involved in the process. The type of neural network was chosen based on accumulated knowledge, considering also the number of involved factors and the expected behaviour response to each set of patterns. The neural networks were trained based on the backpropagation algorithm. The major focus of the network processing was to answer adequately to the occurrence of an injury, considering the role of the involved inputs, and generating an alert signal to this tecidual damage, which could replace the natural reply of the organism. The performance of each model is evaluated comparing the outputs obtained with those expected for each pattern.