Changes in the cholinergic system of rat sciatic nerve and skeletal muscle following suspension induced disuse

Muscle disused induced changes in the cholinergic system of sciatic nerve, slow twitch soleus (SOL) and fast twitch extensor digitorum longus (EDL) muscle were studied in rats. Rats with hindlimbs suspended for 2 to 3 weeks showed marked elevation in the activity of choline acetyltransferase (ChAT) in sciatic nerve (38%), in SOL (108%) and in EDL (67%). Acetylcholinesterase (AChE) activity in SOL increased by 163% without changing the molecular forms pattern of 4S, 10S, 12S, and 16S. No significant changes in activity and molecular forms pattern of AChE were seen in EDL or in AChE activity of sciatic nerve. Nicotinic receptor binding of 3H-acetylcholine was increased in both muscles. When measured after 3 weeks of hindlimb suspension the normal distribution of type 1 fibers in SOL was reduced and a corresponding increase in type IIa and IIb fibers is seen. In EDL no significant change in fiber proportion is observed. Muscle activity, such as loadbearing, appears to have a greater controlling influence on the characteristics of the slow twitch SOL muscle than upon the fast twitch EDL muscle

Use and disuse and the control of acetylcholinesterase activity in fast and slow twitch muscle of rat

The role of acetylcholinesterase (AChE) in neuromuscular transmission is relatively well established, little is known, however, of the mechanisms that regulate its synthesis and control its specific distribution in fast and slow muscle. Innervation plays an important role in the regulation of AChE and elimination of the influence of the nerve by surgical denervation results in a loss of AChE. The influences of the nerve and how they are mediated was investigated. It is suggested that muscle usage and other factors such as materials carried by axonal transport may participate in the regulation of this enzyme. The mechanisms that regulate AChE and its molecular forms in two functionally different forms are studied

Can a microscopic stochastic model explain the emergence of pain cycles in patients?

A stochastic model is here introduced to investigate the molecular mechanisms which trigger the perception of pain. The action of analgesic drug compounds is discussed in a dynamical context, where the competition with inactive species is explicitly accounted for. Finite size effects inevitably perturb the mean-field dynamics: Oscillations in the amount of bound receptors spontaneously manifest, driven by the noise which is intrinsic to the system under scrutiny. These effects are investigated both numerically, via stochastic simulations and analytically, through a large-size expansion. The claim that our findings could provide a consistent interpretative framework to explain the emergence of cyclic behaviors in response to analgesic treatments, is substantiated.Comment: J. Stat. Mech. (Proceedings UPON2008

Spherical harmonic decomposition applied to spatial-temporal analysis of human high-density EEG

We demonstrate an application of spherical harmonic decomposition to analysis of the human electroencephalogram (EEG). We implement two methods and discuss issues specific to analysis of hemispherical, irregularly sampled data. Performance of the methods and spatial sampling requirements are quantified using simulated data. The analysis is applied to experimental EEG data, confirming earlier reports of an approximate frequency-wavenumber relationship in some bands.Comment: 12 pages, 8 figures, submitted to Phys. Rev. E, uses APS RevTeX style

Event-related potential studies of post-traumatic stress disorder: a critical review and synthesis

Despite the sparseness of the currently available data, there is accumulating evidence of information processing impairment in post-traumatic stress disorder (PTSD). Studies of event-related potentials (ERPs) are the main tool in real time examination of information processing. In this paper, we sought to critically review the ERP evidence of information processing abnormalities in patients with PTSD. We also examined the evidence supporting the existence of a relationship between ERP abnormalities and symptom profiles or severity in PTSD patients. An extensive Medline search was performed. Keywords included PTSD or post-traumatic stress disorder, electrophysiology or EEG, electrophysiology, P50, P100, N100, P2, P200, P3, P300, sensory gating, CNV (contingent negative variation) and MMN (mismatch negativity). We limited the review to ERP adult human studies with control groups which were reported in the English language. After applying our inclusion-exclusion review criteria, 36 studies were included. Subjects exposed to wide ranges of military and civilian traumas were studied in these reports. Presented stimuli were both auditory and visual. The most widely studied components included P300, P50 gating, N100 and P200. Most of the studies reported increased P300 response to trauma-related stimuli in PTSD patients. A smaller group of studies reported dampening of responses or no change in responses to trauma-related and/or unrelated stimuli. P50 studies were strongly suggestive of impaired gating in patients with PTSD. In conclusion, the majority of reports support evidence of information processing abnormalities in patients with PTSD diagnosis. The predominance of evidence suggests presence of mid-latency and late ERP components differences in PTSD patients in comparison to healthy controls. Heterogeneity of assessment methods used contributes to difficulties in reaching firm conclusions regarding the nature of these differences. We suggest that future ERP-PTSD studies utilize standardized assessment scales that provide detailed information regarding the symptom clusters and the degree of symptom severity. This would allow assessment of electrophysiological indices-clinical symptoms relationships. Based on the available data, we suggest that ERP abnormalities in PTSD are possibly affected by the level of illness severity. If supported by future research, ERP studies may be used for both initial assessment and treatment follow-up

Jogo educacional sobre avaliação em fisioterapia: uma nova abordagem acadêmica

Este artigo relata a criação de um jogo educacional sobre avaliação em fisioterapia. Uma nova abordagem acadêmica foi proposta para complementar a metodologia atual, basicamente expositiva, especialmente em cursos com conteúdo prático, como a fisioterapia. Uma estratégia pedagógica com casos clínicos e recursos tecnológicos inovadores pode atrair a atenção do estudante, permitindo um aprendizado mais intenso e ativo. O aplicativo foi criado no Adobe Flash CS3 com a linguagem Extensible Markup Language (XML) para a organização das perguntas múltipla escolha. O jogo é composto por quatro salas de atendimento sobre avaliação neurológica, respiratória, musculoesquelética e em terapia intensiva. Há, em cada sala, um caso clínico, seguido de questões múltipla escolha e, por fim, uma questão especial, contendo vídeos ou imagens. Ao responder as questões de forma equivocada, o participante é direcionado a uma sala de estudos com a literatura relacionada ao tema e alguns artigos sugeridos. Para avaliar o impacto desse jogo no processo de aprendizado, serão necessários mais estudos, porém o desenvolvimento de novas estratégias para aprimorar o método de ensino atual é de extrema importância.This article reports the creation of an education game about physiotherapy's evaluation. It proposes the use of new academic approach to improve the existing teaching method of expositive classes and especially for practical courses like physiotherapy. A pedagogical approach with clinical cases and technological resources is capable of attracting the student attention and may stimulate active learning processes. The game was created with Adobe Flash CS3 combined with an Extensible Markup Language (XML) for the questions. Four treatment rooms were created in four different areas: Neurology, Respiratory, Orthopedic and Intensive Care Unit (ICU). In every room there is a case, followed by multiple choice questions and special questions with pictures and videos. There is also a classroom for each case, where some literature and articles for further studies are suggested. To measure the influence of this educational game in the learning process, more studies are needed, however the development of new strategies to improve the existing teaching method is very important

Samples and Case Discussions

Abstract Hundreds of images have already been shown in this text, all with clinical correlation. This section presents a series of cases with EEG samples with interpretation as appropriate. These are typical of EEGs seen in routine clinical practice. At the end of this chapter are a series of surgical case scenarios.</jats:p