Symbolic information approach applied to human intracranial data to characterize and distinguish different congnitive processes.

How the human brain processes information during different cognitive tasks is one of the greatest questions in contemporary neuroscience. Understanding the statistical properties of brain signals during specific activities is one promising way to address this question. Here we analyze freely available data from implanted electrocorticography (ECoG) in five human subjects during two different cognitive tasks in the light of information theory quantifiers ideas. We employ a symbolic information approach to determine the probability distribution function associated with the time series from different cortical areas. Then we utilize these probabilities to calculate the associated Shannon entropy and a statistical complexity measure based on the disequilibrium between the actual time series and one with a uniform probability distribution function. We show that an Euclidian distance in the complexity-entropy plane and an asymmetry index for complexity are useful for comparing the two conditions. We show that our method can distinguish visual search epochs from blank screen intervals in different electrodes and patients. By using a multiscale approach and embedding time delays to downsample the data, we find important timescales in which the relevant information is being processed. We also determine cortical regions and time intervals along the 2-s-long trials that present more pronounced differences between the two cognitive tasks. Finally, we show that the method is useful to distinguish cognitive processes using brain activity on a trial-by-trial basis.

State-dependent complexity of the local field potential in the primary visual cortex.

The local field potential (LFP) is as a measure of the combined activity of neurons within a region of brain tissue. While biophysical modeling schemes for LFP in cortical circuits are well established, there is a paramount lack of understanding regarding the LFP properties along the states assumed in cortical circuits over long periods. Here we use a symbolic information approach to determine the statistical complexity based on Jensen disequilibrium measure and Shannon entropy of LFP data recorded from the primary visual cortex (V1) of urethane-anesthetized rats and freely moving mice. Using these information quantifiers, we find consistent relations between LFP recordings and measures of cortical states at the neuronal level. More specifically, we show that LFP's statistical complexity is sensitive to cortical state (characterized by spiking variability), as well as to cortical layer. In addition, we apply these quantifiers to characterize behavioral states of freely moving mice, where we find indirect relations between such states and spiking variability.

Neuronal heterogeneity modulates phase synchronization between unidirectionally coupled populations with excitation-inhibition balance.

Several experiments and models have highlighted the importance of neuronal heterogeneity in brain dynamics and function. However, how such a cell-to-cell diversity can affect cortical computation, synchronization, and neuronal communication is still under debate. Previous studies have focused on the effect of neuronal heterogeneity in one neuronal population. Here we are specifically interested in the effect of neuronal variability on the phase relations between two populations, which can be related to different cortical communication hypotheses. It has been recently shown that two spiking neuron populations unidirectionally connected in a sender-receiver configuration can exhibit anticipated synchronization (AS), which is characterized by a negative phase lag. This phenomenon has been reported in electrophysiological data of nonhuman primates and human EEG during a visual discrimination cognitive task. In experiments, the unidirectional coupling could be accessed by Granger causality and can be accompanied by either positive or negative phase difference between cortical areas. Here we propose a model of two coupled populations in which the neuronal heterogeneity can determine the dynamical relation between the sender and the receiver and can reproduce phase relations reported in experiments. Depending on the distribution of parameters characterizing the neuronal firing patterns, the system can exhibit both AS and the usual delayed synchronization regime (DS, with positive phase) as well as a zero-lag synchronization regime and phase bistability between AS and DS. Furthermore, we show that our network can present diversity in their phase relations maintaining the excitation-inhibition balance.

Statistical complexity is maximized close to criticality in cortical dynamics.

Complex systems are typically characterized as an intermediate situation between a complete regular structure and a random system. Brain signals can be studied as a striking example of such systems: cortical states can range from highly synchronous and ordered neuronal activity (with higher spiking variability) to desynchronized and disordered regimes (with lower spiking variability). It has been recently shown, by testing independent signatures of criticality, that a phase transition occurs in a cortical state of intermediate spiking variability. Here we use a symbolic information approach to show that, despite the monotonical increase of the Shannon entropy between ordered and disordered regimes, we can determine an intermediate state of maximum complexity based on the Jensen disequilibrium measure. More specifically, we show that statistical complexity is maximized close to criticality for cortical spiking data of urethane-anesthetized rats, as well as for a network model of excitable elements that presents a critical point of a nonequilibrium phase transition.

Educação ambiental e ginástica na Base Nacional Comum Curricular: uma análise sobre a frequência da ocorrência de palavras-chave / Environmental education and gymnastics at the National Common Curricular Base: an analysis of the frequency of occurrence of keywords / Educación ambiental y gimnasia en la Base Curricular Común Nacional: un análisis de la frecuencia de aparición de palabras clave

Objetivo: O estudo busca identificar relações entre ginástica e educação ambiental na Base Nacional Comum Curricular na etapa do Ensino Fundamental. Metodologia: A metodologia de estudo é mista, com base na estratégia de triangulação concomitante, através da busca das seguintes palavras-chave: ambiental, ambiente, educação ambiental, ginástica, meio ambiente, natureza e socioambiental. Resultados: As análises de frequência de ocorrência das palavras-chave, indicando pouca referência das palavras-chave relacionados ao campo da educação ambiental no componente curricular da Educação Física. A frequência das palavras-chave ambiental tem baixa ocorrência, seguida das palavras-chave natureza, ambiente e ginástica. As palavras educação ambiental, meio ambiente e socioambiental não aparecem nenhuma vez. Conclusão: Portanto, foi possível verificar que a educação ambiental aparece como um tema contemporâneo que deve estar presente no currículo e nas propostas pedagógicas, mas não há aprofundamento didático ou metodológico e apenas a citação da lei não garante o tema nas aulas e nos currículos. É necessária uma revisão crítica do documento na formação inicial de professores para fundamentar o planejamento e organização do trabalho pedagógico na sua atuação docente. Ao se tratar do conteúdo ginástica, a Base Nacional Comum Curricular fornece subsídios para auxiliar o professor a desenvolver este conteúdo na escola.

Objective: The study aimedto identify relationships between gymnastics and environmental education in the Common Base National Curriculum in the elementary school stage. Methodology: The study methodology is mixed, based on the concomitant triangulation strategy, through the search for the following keywords: environmental, environment, environmental education, gymnastics, environment, nature and socio-environmental. Results: Analysis of the frequency of occurrence of the keywords, indicating little reference to the key terms related to the field of environmental education in the curriculum component of Physical Education. The frequency of the keywords environmental has a low occurrence, followed by the keywords nature, environment and gymnastics. The words environmental education, environment and socio-environmental do not appear once. Conclusion:Therefore, it was possible to verify that environmental education appears as a contemporary theme that must be present in the curriculum and in the pedagogical proposals, but there is no didactic or methodological deepening and only the mention of the law does not guarantee the theme in classes and curricula. A critical revision of the document in the initial training of teachers is necessary to support the planning and organization of pedagogical work in its teaching performance. When dealing with gymnastic content, the National Common Curricular Base provides subsidies to assist the teacher to develop this content at school.

Objetivo: El estudio está en el área de Educación Física buscando identificar relaciones entre gimnasia y educación ambiental en el Currículo Nacional de Base Común en la etapa de la escuela primaria.Metodología:La metodología de estudio es mixta, basada en la estrategia de triangulación concomitante, a través de la búsqueda de las siguientes palabras clave: medioambiental, medioambiental, educación medioambiental, gimnasia, medioambiente, naturaleza y socioambiental. Resultados: Análisis de la frecuencia de aparición de las palabras clave, indicando poca referencia a los términos clave relacionados con el campo de la educación ambiental en el componente curricular de la Educación Física. La frecuencia de las palabras clave medioambientales es poco frecuente, seguida de las palabras clave naturaleza, medio ambiente y gimnasia. Las palabras educación ambiental, medio ambiente y socioambiental no aparecen una vez. Conclusión: Por lo tanto, fue posible verificar que la educación ambiental aparece como un tema contemporáneo que debe estar presente en el plan de estudios y en las propuestas pedagógicas, pero no existe una profundización didáctica o metodológica y solo la mención de la ley no garantiza el tema en las clases y los planes de estudio. Es necesaria una revisión crítica del documento en la formación inicial de los docentes para apoyar la planificación y organización del trabajo pedagógico en su desempeño docente. Cuando se trata de contenido gimnástico, la BaseCurricular Común Nacional proporciona subsidios para ayudar al maestro a desarrollar este contenido en la escuela.

Phase bistability between anticipated and delayed synchronization in neuronal populations.

Two dynamical systems unidirectionally coupled in a sender-receiver configuration can synchronize with a nonzero phase lag. In particular, the system can exhibit anticipated synchronization (AS), which is characterized by a negative phase lag, if the receiver also receives a delayed negative self-feedback. Recently, AS was shown to occur between cortical-like neuronal populations in which the self-feedback is mediated by inhibitory synapses. In this biologically plausible scenario, a transition from the usual delayed synchronization (with positive phase lag) to AS can be mediated by the inhibitory conductances in the receiver population. Here we show that depending on the relation between excitatory and inhibitory synaptic conductances the system can also exhibit phase bistability between anticipated and delayed synchronization. Furthermore, we show that the amount of noise at the receiver and the synaptic conductances can mediate the transition from stable phase locking to a bistable regime and eventually to a phase drift. We suggest that our spiking neuronal populations model could be potentially useful to study phase bistability in cortical regions related to bistable perception.

Inhibitory autapse mediates anticipated synchronization between coupled neurons.

Two identical autonomous dynamical systems unidirectionally coupled in a sender-receiver configuration can exhibit anticipated synchronization (AS) if the receiver neuron also receives a delayed negative self-feedback. Recently, AS was shown to occur in a three-neuron motif with standard chemical synapses where the delayed inhibition was provided by an interneuron. Here, we show that a two-neuron model in the presence of an inhibitory autapse, which is a massive self-innervation present in the cortical architecture, may present AS. The GABAergic autapse regulates the internal dynamics of the receiver neuron and acts as the negative delayed self-feedback required by dynamical systems in order to exhibit AS. In this biologically plausible scenario, a smooth transition from the usual delayed synchronization (DS) to AS typically occurs when the inhibitory conductance is increased. The phenomenon is shown to be robust when model parameters are varied within a physiological range. For extremely large values of the inhibitory autapse the system undergoes to a phase-drift regime in which the receiver is faster than the sender. Furthermore, we show that the inhibitory autapse promotes a faster internal dynamics of the free-running Receiver when the two neurons are uncoupled, which could be the mechanism underlying anticipated synchronization and the DS-AS transition.

Anticipated synchronization in neuronal circuits unveiled by a phase-response-curve analysis.

Anticipated synchronization (AS) is a counterintuitive behavior that has been observed in several systems. When AS occurs in a sender-receiver configuration, the latter can predict the future dynamics of the former for certain parameter values. In particular, in neuroscience AS was proposed to explain the apparent discrepancy between information flow and time lag in the cortical activity recorded in monkeys. Despite its success, a clear understanding of the mechanisms yielding AS in neuronal circuits is still missing. Here we use the well-known phase-response-curve (PRC) approach to study the prototypical sender-receiver-interneuron neuronal motif. Our aim is to better understand how the transitions between delayed to anticipated synchronization and anticipated synchronization to phase-drift regimes occur. We construct a map based on the PRC method to predict the phase-locking regimes and their stability. We find that a PRC function of two variables, accounting simultaneously for the inputs from sender and interneuron into the receiver, is essential to reproduce the numerical results obtained using a Hodgkin-Huxley model for the neurons. On the contrary, the typical approximation that considers a sum of two independent single-variable PRCs fails for intermediate to high values of the inhibitory coupling strength of the interneuron. In particular, it loses the delayed-synchronization to anticipated-synchronization transition.

Inhibitory loop robustly induces anticipated synchronization in neuronal microcircuits.

We investigate the synchronization properties between two excitatory coupled neurons in the presence of an inhibitory loop mediated by an interneuron. Dynamic inhibition together with noise independently applied to each neuron provide phase diversity in the dynamics of the neuronal motif. We show that the interplay between the coupling strengths and the external noise controls the phase relations between the neurons in a counterintuitive way. For a master-slave configuration (unidirectional coupling) we find that the slave can anticipate the master, on average, if the slave is subject to the inhibitory feedback. In this nonusual regime, called anticipated synchronization (AS), the phase of the postsynaptic neuron is advanced with respect to that of the presynaptic neuron. We also show that the AS regime survives even in the presence of unbalanced bidirectional excitatory coupling. Moreover, for the symmetric mutually coupled situation, the neuron that is subject to the inhibitory loop leads in phase.

Antimicrobial Activity of Copaiba (Copaifera officinalis) and Pracaxi (Pentaclethra macroloba) Oils against Staphylococcus Aureus: Importance in Compounding for Wound Care.

The Amazon rainforest is the largest reserve of natural products in the world. Its rich biodiversity of medicinal plants has been utilized by local populations for hundreds of years for the prevention and treatment of various diseases and ailments. Oil extracts from plant species such as Copaifera officinalis and Pentaclethra macroloba are used in compounded formulations for their antiinflammatory, antimicrobial, emollient, moisturizing, and wound-healing activities. The objective of this study was to investigate the in vitro bacteriostatic effect of two Amazonian oils, Copaiba and Pracaxi, against Staphylococcus aureus, a clinically important microorganism responsible for wound infection, to support the use of these oils as novel natural products for compounded wound-treatment modalities. The antibacterial activity of Copaiba and Pracaxi oils against a standard strain of Staphylococcus aureus was assessed using broth microdilution to determine the Minimum Inhibitory Concentration and Minimum Bactericidal Concentration of the oil extracts. Copaiba oil demonstrated antibacterial activity against Staphylococcus aureus, with a Minimum Inhibitory Concentration of 0.3125 mg/mL and a Minimum Bactericidal Concentration of 0.3125 mg/mL. Conversely, Pracaxi oil failed to inhibit Staphylococcus aureus growth. While additional studies are required to further evaluate the antimicrobial activity of Pracaxi oil, even low concentrations of Copaiba oil effectively inhibited Staphylococcus aureus growth, supporting its potential use as a promising adjuvant in compounded topical formulations for wound and scar healing.

A symbolic information approach to determine anticipated and delayed synchronization in neuronal circuit models.

The phenomenon of synchronization between two or more areas of the brain coupled asymmetrically is a relevant issue for understanding mechanisms and functions within the cerebral cortex. Anticipated synchronization (AS) refers to the situation in which the receiver system synchronizes to the future dynamics of the sender system while the intuitively expected delayed synchronization (DS) represents exactly the opposite case. AS and DS are investigated in the context of causal information formalism. More specifically, we use a multi-scale symbolic information-theory approach for discriminating the time delay displayed between two areas of the brain when they exchange information.

Self-Organized Near-Zero-Lag Synchronization Induced by Spike-Timing Dependent Plasticity in Cortical Populations.

Several cognitive tasks related to learning and memory exhibit synchronization of macroscopic cortical areas together with synaptic plasticity at neuronal level. Therefore, there is a growing effort among computational neuroscientists to understand the underlying mechanisms relating synchrony and plasticity in the brain. Here we numerically study the interplay between spike-timing dependent plasticity (STDP) and anticipated synchronization (AS). AS emerges when a dominant flux of information from one area to another is accompanied by a negative time lag (or phase). This means that the receiver region pulses before the sender does. In this paper we study the interplay between different synchronization regimes and STDP at the level of three-neuron microcircuits as well as cortical populations. We show that STDP can promote auto-organized zero-lag synchronization in unidirectionally coupled neuronal populations. We also find synchronization regimes with negative phase difference (AS) that are stable against plasticity. Finally, we show that the interplay between negative phase difference and STDP provides limited synaptic weight distribution without the need of imposing artificial boundaries.

Viral load and epidemiological profile of patients infected by pandemic influenza a (H1N1) 2009 and seasonal influenza a virus in Southern Brazil.

Correlation between virologic profile and clinical features of patients infected by influenza virus provides important information for epidemiological control and clinical management of future disease outbreaks. Samples from patients in Southern Brazil, from June to December 2009, were examined and the viral load was correlated with epidemiological data. All samples were analyzed by qRT-PCR for detection of the 2009-pandemic Influenza A (H1N1). Relative viral loads were assessed based on the 2(-ΔCT) method and epidemiological data were obtained for each patient, following ethical policies. A total of 933 samples were positive for pH1N1 (2009) influenza; 172 were positive for seasonal influenza A; 13 were undetermined; 1992 samples were negative for influenza A. Combined molecular and epidemiological data were available for 38 seasonal and 198 pandemic samples. The median viral load was higher in pandemic than in seasonal influenza samples; in patients infected with pH1N1 (2009), viral load associated positively with chills, myalgia and rhinorrhea, and negatively with dyspnea, but no association was observed with other symptoms, nor with clinical conditions such as pregnancy, smoking, immunodepression and co-morbidities. Regarding patients infected with seasonal influenza, viral loads did not show statistically significant association with any of the symptoms. This is the first study in Brazil that examines epidemiological and molecular data from the 2009 influenza pandemic. The results may serve as a basis for developing strategies to control human-to-human infection and viral dissemination, and for implementing effective measures and public health policies against future novel disease outbreaks.

New PHA products using unrelated carbon sources

Polyhydroxyalkanoates (PHA) are natural polyesters stored by a wide range of bacteria as carbon source reserve. Due to its chemical characteristics and biodegradability PHA can be used in chemical, medical and pharmaceutical industry for many human purposes. Over the past years, few Burkholderia species have become known for production of PHA. Aside from that, these bacteria seem to be interesting for discovering new PHA compositions which is important to different industrial applications. In this paper, we introduce two new strains which belong either to Burkholderia cepacia complex (Bcc) or genomovar-type, Burkholderia cepacia SA3J and Burkholderia contaminans I29B, both PHA producers from unrelated carbon sources. The classification was based on 16S rDNA and recA partial sequence genes and cell wall fatty acids composition. These two strains were capable to produce different types of PHA monomers or precursors. Unrelated carbon sources were used for growth and PHA accumulation. The amount of carbon source evaluated, or mixtures of them, was increased with every new experiment until it reaches eighteen carbon sources. As first bioprospection experiments staining methods were used with colony fluorescent dye Nile Red and the cell fluorescent dye Nile Blue A. Gas chromatography analysis coupled to mass spectrometry was used to evaluate the PHA composition on each strain cultivated on different carbon sources. The synthesized polymers were composed by short chain length-PHA (scl-PHA), especially polyhydroxybutyrate, and medium chain length-PHA (mcl-PHA) depending on the carbon source used.

Pyodermatitis-pyostomatitis vegetans: case report and review of medical literature.

Pyodermatitis-pyostomatitis vegetans is a rare inflammatory dermatosis of unknown etiology, with a typical mucocutaneous involvement. We report the case of a woman with pustular and vesicular lesions in the axillae, evolving with vegetating plaques and pustules with annular grouping. The disease progressed with vulvar and inguinal involvement as well as involvement of the oral, nasal and ocular mucous membranes. She started the treatment with prednisone (40 mg/day), with remission of the lesions after one month of use of such medication. Association with inflammatory bowel disease occurs in 70% of the cases. Immunofluorescence, which is typically negative, helps to characterize the disease. A rapid response to systemic steroids is expected.

Anticipated synchronization in a biologically plausible model of neuronal motifs.

Two identical autonomous dynamical systems coupled in a master-slave configuration can exhibit anticipated synchronization (AS) if the slave also receives a delayed negative self-feedback. Recently, AS was shown to occur in systems of simplified neuron models, requiring the coupling of the neuronal membrane potential with its delayed value. However, this coupling has no obvious biological correlate. Here we propose a canonical neuronal microcircuit with standard chemical synapses, where the delayed inhibition is provided by an interneuron. In this biologically plausible scenario, a smooth transition from delayed synchronization (DS) to AS typically occurs when the inhibitory synaptic conductance is increased. The phenomenon is shown to be robust when model parameters are varied within a physiological range. Since the DS-AS transition amounts to an inversion in the timing of the pre- and post-synaptic spikes, our results could have a bearing on spike-timing-dependent plasticity models.

Piodermatite-pioestomatite vegetante: relato de caso e revisão de literatura / Pyodermatitis-pyostomatitis vegetans: case report and review of medical literarture

A piodermatite-pioestomatite vegetante é uma rara dermatose inflamatória de etiologia desconhecida, com típico comprometimento mucocutâneo. Relatamos caso de paciente feminina com lesões pustulosas e vesiculosas em axilas, evoluindo com placas vegetantes e pústulas com agrupamento anular. Houve progressão com comprometimento vulvar, inguinal e mucosas oral, nasal e ocular. Proposto o diagnóstico, optou-se por iniciar prednisona 40mg ao dia, com remissão das lesões após um mês de uso da medicação. A associação com doença inflamatória intestinal ocorre em 70 por cento dos casos. A imunofluorescência é um fator que ajuda a caracterizar a doença, sendo tipicamente negativa. A rápida resposta à terapêutica com corticosteroides sistêmicos é esperada.

Pyodermatitis-pyostomatitis vegetans is a rare inflammatory dermatosis of unknown etiology, with a typical mucocutaneous involvement. We report the case of a woman with pustular and vesicular lesions in the axillae, evolving with vegetating plaques and pustules with annular grouping. The disease progressed with vulvar and inguinal involvement as well as involvement of the oral, nasal and ocular mucous membranes. She started the treatment with prednisone (40 mg/day), with remission of the lesions after one month of use of such medication. Association with inflammatory bowel disease occurs in 70 percent of the cases. Immunofluorescence, which is typically negative, helps to characterize the disease. A rapid response to systemic steroids is expected.

Acute acneiform eruption induced by interferon beta-1b during treatment for multiple sclerosis.

Multiple sclerosis is an inflammatory demyelinating disease of presumed autoimmune origin that affects the central nervous system. The main form of therapy is based on the use of immunomodulators such as interferon beta, which are usually well tolerated. Skin manifestations resulting from treatment with interferon beta-1b consist principally of reactions at the site of subcutaneous application of the drug. The present case report describes a female patient who developed an acneiform eruption resulting from treatment with interferon beta-1b.

Erupção acneiforme aguda induzida por interferon beta-1b durante tratamento para esclerose múltipla / Acute acneiform eruption induced by interferon beta-1b during treatment for multiple sclerosis

Esclerose múltipla é uma doença inflamatória desmielinizante, com presumida origem autoimune, que afeta o sistema nervoso central. A principal modalidade terapêutica é baseada no uso de imunomoduladores, como o interferon beta, que são geralmente bem tolerados. As manifestações cutâneas secundárias ao interferon beta-1b são representadas, na maioria das vezes, por reações no local de sua aplicação subcutânea. Descrevemos o caso de uma paciente do sexo feminino que desenvolveu um quadro de erupção acneiforme pelo interferon beta-1b.

Multiple sclerosis is an inflammatory demyelinating disease of presumed autoimmune origin that affects the central nervous system. The main form of therapy is based on the use of immunomodulators such as interferon beta, which are usually well tolerated. Skin manifestations resulting from treatment with interferon beta-1b consist principally of reactions at the site of subcutaneous application of the drug. The present case report describes a female patient who developed an acneiform eruption resulting from treatment with interferon beta-1b.

New PHA products using unrelated carbon sources.

Polyhydroxyalkanoates (PHA) are natural polyesters stored by a wide range of bacteria as carbon source reserve. Due to its chemical characteristics and biodegradability PHA can be used in chemical, medical and pharmaceutical industry for many human purposes. Over the past years, few Burkholderia species have become known for production of PHA. Aside from that, these bacteria seem to be interesting for discovering new PHA compositions which is important to different industrial applications. In this paper, we introduce two new strains which belong either to Burkholderia cepacia complex (Bcc) or genomovar-type, Burkholderia cepacia SA3J and Burkholderia contaminans I29B, both PHA producers from unrelated carbon sources. The classification was based on 16S rDNA and recA partial sequence genes and cell wall fatty acids composition. These two strains were capable to produce different types of PHA monomers or precursors. Unrelated carbon sources were used for growth and PHA accumulation. The amount of carbon source evaluated, or mixtures of them, was increased with every new experiment until it reaches eighteen carbon sources. As first bioprospection experiments staining methods were used with colony fluorescent dye Nile Red and the cell fluorescent dye Nile Blue A. Gas chromatography analysis coupled to mass spectrometry was used to evaluate the PHA composition on each strain cultivated on different carbon sources. The synthesized polymers were composed by short chain length-PHA (scl-PHA), especially polyhydroxybutyrate, and medium chain length-PHA (mcl-PHA) depending on the carbon source used.