RESUMO
Paracoccidioidomycosis is a systemic fungal disease associated with agricultural activities. Its incidence and prevalence are underestimated because of the lack of reporting in several Brazilian states. If paracoccidiodomycosis is not diagnosed and treated early and adequately, endemic fungal infection may result in serious sequelae. In addition to the Paracoccidioides brasiliensis (P. brasiliensis) complex, the appearance of a new species, Paracoccidioides lutzii (P. lutzii), in Rondônia state, where the disease has reached epidemic levels, and in the country's Midwest region and Pará state, are challenges to diagnosis and to the urgent availability of antigens that are reactive with patients' sera. These guidelines aim to update the first Brazilian consensus on paracoccidioidomycosis by providing evidence-based recommendations for bedside patient management. The guidelines provide data on etiology, epidemiology, immunopathogenesis, diagnosis, treatment and sequelae, with emphasis on diagnosis and treatment, as well as current recommendations and challenges in this field of knowledge.
A paracoccidioidomicose (PCM) é uma micose sistêmica, relacionada às atividades agrícolas, com incidência e prevalência subestimadas, pela ausência de notificação em várias Unidades da Federação (UFs). A evolução insidiosa do quadro clínico pode ter como consequência sequelas graves se o diagnóstico e o tratamento não forem instituídos precoce e adequadamente. Ao lado do complexo Paracoccidioides brasiliensis (P. brasiliensis), a descrição de nova espécie, Paracoccidioides lutzii (P. lutzii), em Rondônia, onde a doença alcançou níveis epidêmicos, bem como na região Centro-Oeste e no Pará, constituem-se em desafios para a instituição do diagnóstico e a urgente disponibilização de antígenos que tenham reatividade com os soros dos pacientes. Este consenso visa atualizar o primeiro consenso brasileiro em PCM, estabelecendo recomendações para o manejo clínico do paciente, com base nas evidências conhecidas. São apresentados dados de etiologia, epidemiologia, imunopatogenia, diagnóstico, terapêutica e sequelas, enfatizando-se o diagnóstico e a terapêutica, bem como recomendações e desafios atuais nessa área do conhecimento.
La paracoccidioidomicosis es una micosis sistémica, relacionada con las actividades agrícolas, con incidencia y prevalencia subestimadas por la ausencia de notificación en varios estados. La evolución insidiosa del cuadro clínico puede tener como consecuencia secuelas graves si el diagnóstico y el tratamiento no se establecen precoz y adecuadamente. Al lado del complejo Paracoccidioides brasiliensis (P. brasiliensis), la descripción de nueva especie, Paracoccidioides lutzii (P. lutzii) en Rondonia, donde la enfermedad alcanzó niveles epidémicos, y en la región Centro Oeste y en Pará, se constituyen en desafíos para la institución del diagnóstico y la urgente puesta a disposición de antígenos que tengan reactividad con los sueros de los pacientes. El presente consenso tiene por objeto actualizar el primer consenso brasileño en paracoccidioidomicosis, estableciendo recomendaciones para el manejo del paciente al borde del lecho, con base en las evidencias conocidas. Se presentan datos de etiología, epidemiología, inmunopatogenia, diagnóstico, terapéutica y secuelas, enfatizando el diagnóstico y terapéutica, así como recomendaciones desafíos y actuales en esta área del conocimiento.
Assuntos
Antígenos de Fungos/imunologia , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/terapia , Brasil/epidemiologia , Humanos , Incidência , Paracoccidioidomicose/diagnóstico , Paracoccidioidomicose/epidemiologia , PrevalênciaRESUMO
Paracoccidioidomycosis is a systemic fungal disease occurring in Latin America that is associated with rural environments and agricultural activities. However, the incidence and prevalence of paracoccidiodomycosis is underestimated because of the lack of compulsory notification. If paracoccidiodomycosis is not diagnosed and treated early and adequately, the endemic fungal infection could result in serious sequelae. While the Paracoccidioides brasiliensis ( P. brasiliensis ) complex has been known to be the causal agent of paracoccidiodomycosis, a new species, Paracoccidioides lutzii ( P. lutzii ), has been reported in Rondônia, where the disease has reached epidemic levels, and in the Central West and Pará. Accurate diagnoses and availability of antigens that are reactive with the patients' sera remain significant challenges. Therefore, the present guidelines aims to update the first Brazilian consensus on paracoccidioidomycosis by providing evidence-based recommendations for bedside patient management. This consensus summarizes etiological, ecoepidemiological, molecular epidemiological, and immunopathological data, with emphasis on clinical, microbiological, and serological diagnosis and management of clinical forms and sequelae, as well as in patients with comorbidities and immunosuppression. The consensus also includes discussion of outpatient treatments, severe disease forms, disease prevalence among special populations and resource-poor settings, a brief review of prevention and control measures, current challenges and recommendations.
Assuntos
Antifúngicos/uso terapêutico , Gerenciamento Clínico , Paracoccidioidomicose/tratamento farmacológico , Paracoccidioidomicose/patologia , Brasil , Consenso , Diagnóstico Diferencial , Humanos , Itraconazol/uso terapêutico , América Latina , ParacoccidioidesRESUMO
An information-theoretic framework known as integrated information theory (IIT) has been introduced recently for the study of the emergence of consciousness in the brain [D. Balduzzi and G. Tononi, PLoS Comput. Biol. 4, e1000091 (2008)]. IIT purports that this phenomenon is to be equated with the generation of information by the brain surpassing the information that the brain's constituents already generate independently of one another. IIT is not fully plausible in its modeling assumptions nor is it testable due to severe combinatorial growth embedded in its key definitions. Here we introduce an alternative to IIT which, while inspired in similar information-theoretic principles, seeks to address some of IIT's shortcomings to some extent. Our alternative framework uses the same network-algorithmic cortical model we introduced earlier [A. Nathan and V. C. Barbosa, Phys. Rev. E 81, 021916 (2010)] and, to allow for somewhat improved testability relative to IIT, adopts the well-known notions of information gain and total correlation applied to a set of variables representing the reachability of neurons by messages in the model's dynamics. We argue that these two quantities relate to each other in such a way that can be used to quantify the system's efficiency in generating information beyond that which does not depend on integration. We give computational results on our cortical model and on variants thereof that are either structurally random in the sense of an Erdos-Rényi random directed graph or structurally deterministic. We have found that our cortical model stands out with respect to the others in the sense that many of its instances are capable of integrating information more efficiently than most of those others' instances.
Assuntos
Encéfalo/patologia , Biologia Computacional/métodos , Estado de Consciência/fisiologia , Algoritmos , Animais , Biofísica/métodos , Córtex Cerebral/patologia , Simulação por Computador , Humanos , Modelos Neurológicos , Modelos Teóricos , Rede Nervosa/fisiologia , Probabilidade , SoftwareRESUMO
When a neuron fires and the resulting action potential travels down its axon toward other neurons' dendrites, the effect on each of those neurons is mediated by the strength of the synapse that separates it from the firing neuron. This strength, in turn, is affected by the postsynaptic neuron's response through a mechanism that is thought to underlie important processes such as learning and memory. Although of difficult quantification, cortical synaptic strengths have been found to obey a long-tailed unimodal distribution peaking near the lowest values (approximately lognormal), thus confirming some of the predictive models built previously. Most of these models are causally local, in the sense that they refer to the situation in which a number of neurons all fire directly at the same postsynaptic neuron. Consequently, they necessarily embody assumptions regarding the generation of action potentials by the presynaptic neurons that have little biological interpretability. We introduce a network model of large groups of interconnected neurons and demonstrate, making none of the assumptions that characterize the causally local models, that its long-term behavior gives rise to a distribution of synaptic weights (the mathematical surrogates of synaptic strengths) with the same properties that were experimentally observed. In our model, the action potentials that create a neuron's input are, ultimately, the product of network-wide causal chains relating what happens at a neuron to the firings of others. Our model is then of a causally global nature and predicates the emergence of the synaptic-weight distribution on network structure and function. As such, it has the potential to become instrumental also in the study of other emergent cortical phenomena.
Assuntos
Algoritmos , Modelos Biológicos , Rede Nervosa , Sinapses/fisiologia , Simulação por Computador , ProbabilidadeRESUMO
We consider flocks of artificial birds and study the emergence of V-like formations during flight. We introduce a small set of fully distributed positioning rules to guide the birds' movements and demonstrate, by means of simulations, that they tend to lead to stabilization into several of the well-known V-like formations that have been observed in nature. We also provide quantitative indicators that we believe are closely related to achieving V-like formations, and study their behavior over a large set of independent simulations.