Atypical Motor Neuron Disease variants: Still a diagnostic challenge in Neurology.

Motor neuron disease (MND) represents a wide and heterogeneous expanding group of disorders involving the upper or lower motor neurons, mainly represented by amyotrophic lateral sclerosis (ALS), primary lateral sclerosis, progressive muscular atrophy and progressive bulbar palsy. Primary motor neuronopathies are characterized by progressive degenerative loss of anterior horn cell motoneurons (lower motor neurons) or loss of giant pyramidal Betz cells (upper motor neurons). Despite its well-known natural history, pathophysiological and clinical characteristics for the most common MND, atypical clinical presentation and neurodegenerative mechanisms are commonly observed in rare clinical entities, so-called atypical variants of MND-ALS, including flail-leg syndrome, flail-arm syndrome, facial-onset sensory and motor neuronopathy (FOSMN), finger extension weakness and downbeat nystagmus (FEWDON-MND) and long-lasting and juvenile MND-ALS. Herein, we provide a review article presenting clinical, genetic, pathophysiological and neuroimaging findings of atypical variants of MND-ALS in clinical practice.

Retention systems for extraoral maxillofacial prosthetic implants: a critical review.

We describe the techniques available for retention of implant-supported prostheses: bar-clips, O-rings, and magnets. We present reported preferences and, although this is limited by the heterogeneity of methods used and patients studied, we hope we have identified the best retention systems for maxillofacial prosthetic implants. If practitioners know the advantages and disadvantages of each system, they can choose the most natural and comfortable prosthesis. We searched the PubMed and Scopus databases, and restricted our search to papers published 2001-13. MeSH terms used were Maxillofacial prosthesis and Craniofacial prosthesis OR Craniofacial prostheses. We found a total of 2630 papers, and after duplicates had been removed we analysed the rest and found 25 papers for review. Of these, 12 were excluded because they were case reports or non-systematic reviews. Of the remaining 13, 10 described group analyses and seemed appropriate to find practitioner's choices, as cited in the abstract (n=1611 prostheses). Three papers did not mention the type of prosthetic connection used, so were excluded. The most popular choices for different conditions were analysed, though the sites and retention systems were not specified in all 10 papers. The bar-clip system was the most used in auricular (6/10 papers) and nasal prostheses (4/10). For the orbital region, 6/10 favoured magnets. Non-osseointegrated mechanical or adhesive retention techniques are the least expensive and have no contraindications. When osseointegrated implants are possible, each facial region has a favoured system. The choice of system is influenced by two factors: standard practice and the abilities of the maxillofacial surgeon and maxillofacial prosthetist.

Homeostatic plasticity induced by brief activity deprivation enhances long-term potentiation in the mature rat hippocampus.

Different forms of plasticity occur concomitantly in the nervous system. Whereas homeostatic plasticity monitors and maintains neuronal activity within a functional range, Hebbian changes such as long-term potentiation (LTP) modify the relative strength of specific synapses after discrete changes in activity and are thought to provide the cellular basis for learning and memory. Here, we assessed whether homeostatic plasticity could influence subsequent LTP in acute hippocampal slices that had been briefly deprived of activity by blocking action potential generation and N-methyl-D-aspartate (NMDA) receptor activation for 3 h. Activity deprivation enhanced the frequency and the amplitude of spontaneous miniature excitatory postsynaptic currents and enhanced basal synaptic transmission in the absence of significant changes in intrinsic excitability. Changes in the threshold for Hebbian plasticity were evaluated by inducing LTP with stimulation protocols of increasing strength. We found that activity-deprived slices consistently showed higher LTP magnitude compared with control conditions even when using subthreshold theta-burst stimulation. Enhanced LTP in activity-deprived slices was also observed when picrotoxin was used to prevent the modulation of GABAergic transmission. Finally, we observed that consecutive LTP inductions attained a higher magnitude of facilitation in activity-deprived slices, suggesting that the homeostatic plasticity mechanisms triggered by a brief period of neuronal silencing can both lower the threshold and raise the ceiling for Hebbian modifications. We conclude that even brief periods of altered activity are able to shape subsequent synaptic transmission and Hebbian plasticity in fully developed hippocampal circuits.

["Me? I'm just here, part of the world". A field experience on endemic disease control in Cansanção, Minas Gerais, Brazil]. / "Eu? Eu esou aí, compondo o mundo". Uma experiência de controle de endemia, pesquisa e participação popular vivida em Cansanção, Minas Gerais, Brasil.

This free-style article reports an experience with Chagas' disease control involving community participation in the Jequitinhonha Valley (Minas Gerais, Brazil) implemented during the 1980s and recently reevaluated. As an action-based participant research project, it was supported by the Socioeconomic TDR Committee (WHO/WB/UNDP) in the area of Popular Education. The main objective was to investigate the meaning of Chagas' disease from the community's perspective, seeking alternative control measures with their participation. Despite the extremely high prevalence of the disease, it was no perceived as a priority by the population, who were living in destitution and simply fighting for their very survival. Given this situation, Chagas' disease control was performed in an integrated manner, taking other community needs into account. The article suggests some forms of participation in the control of endemic diseases, taking into account the people's knowledge, focused on the "here and now" in an integrated vision of both their problems and their ability to mobilize behind concrete interests. Changes are also needed in the relationship between outside agents and the community, reciprocity in the involvement with community, a permanent attitude of listening and solidarity, a "self-diagnosis", and organization of population.

Every day life in new settlement areas and malaria control strategies.

PIP: There is a constant increase of new malaria cases in Brazil; 98% from the Amazon region, mainly in prospecting areas and new settlements. Available disease control strategies are inadequate in the face of this complex problem. The multiple and interrelated causality factors instead demand a transdisciplinary approach. The author used interviews, open agenda investigative meetings, field observations, photography, tape recordings, a field diary, and other methods to document and understand the challenges malaria poses in recently opened human settlement areas in rural Brazil. She lived with the people, visited their workplaces, talked to groups about life, interviewed men who work in the area, and spent time with pastoral agents of the Roman Catholic Church. Study findings are presented with direct citations from her subjects. The ethical dimensions of research practice are also considered.^ieng