Sistema de neurónios espelho no síndrome de down: estudo das variações dos ritmos Mu No Eeg

A capacidade de compreensão das acções dos outros e de imitação tem sido descrita como fundamental para a cognição social do ser humano. Recentemente tem sido atribuída a responsabilidade desta capacidade a um sistema neuronal denominado de Sistema de Neurónios Espelho, que se tem demonstrado estar afectado em perturbações mentais que se caracterizam por alterações severas da teoria da mente e da empatia, como é o caso do autismo. No caso do Síndrome de Down, verifica-se a coexistência de boas competências sociais e de capacidades práxicas e de imitação intactas, com dificuldades de interpretação de situações sociais e de reconhecimento de emoções, que nos levam a questionar acerca da actividade do seu Sistema de Neurónios Espelho. As oscilações do ritmo de frequências um (8-13 Hz) no córtex sensório-motor perante a observação de acções são consideradas um reflexo da actividade dos neurónios espelho, estando estabelecido que em pessoas saudáveis ocorre uma supressão mu na realização de movimentos com o membro superior e na sua observação quando realizados por outras pessoas. Neste estudo registou-se electroencefalograficamente a supressão dos ritmos mu em 11 pessoas com SD e em 20 pessoas sem SD nas seguintes condições: observação de um vídeo com duas bolas em movimento, observação de um vídeo com um movimento repetido de uma mão e realização movimentos com a mão. A baseline foi registada através da observação de um ponto estático. Constatamos que existe supressão dos ritmos mu na observação das acções dos outros em pessoas com Síndrome Down da mesma forma que ocorre na realização do próprio movimento, sugerindo uma relativa preservação do funcionamento dos neurónios espelho e dos mecanismos básicos de cognição social. Estes resultados vão de encontro aos estudos que apontam para a integridade das capacidades de imitação no Síndrome Down. Verificamos também que não se encontram diferenças significativas na supressão dos ritmos mu entre os grupos de pessoas com Síndrome Down e de Controlo em relação às condições usadas na investigação.

Fungidal and bacterial activity of N,N-dimethyl-4-(2,2,2-trichloro-1-(phenylamino)ethyl)aniline

N,N-dimethyl-4-((phenylamino)methyl)aniline (1) was prepared by condensation of aniline and 4-(dimethylamino)benzaldehyde [1] N,N-dimethyl-4-(2,2,2-trichloro-1-(phenylamino)ethyl)aniline (2) was synthesized by trichloromethylation of the imine (N,N-dimethyl-4-((phenylimino)methyl)aniline (1)) with trichloroacetic anhydride under microwave irradiation [2] (Sheme 1). The present work reports the study of bacterial and yeast activity for the compound 2. The bacteria used in this study are Staphylococcus aureus, Escherichia coli and the yeast are Saccharomyces Cerevisiae Candida albican.The results that we will present are the determination of minimal inhibitory concentration (MIC), by means of microdilution by plate method and the specific growth constants for this microorganism. Further studies are being performed to determine viability and cellular injury with this drug.

Development and biological evaluation of API-ILs based on anti-bacterial and anti-fungal drugs

In recent years Ionic Liquids (ILs) are being applied in life sciences. ILs are being produce with active pharmaceutical drugs (API) as they can reduce polymorphism and drug solubility problems [1] Also ILs are being applied as a drug delivery device in innovative therapies What is appealing in ILs is the ILs building up platform, the counter-ion can be carefully chosen in order to avoid undesirable side effects or to give innovative therapies in which two active ions are paired. This work shows ILs based on ampicillin (an anti-bacterial agent) and ILs based on Amphotericin B. Also we show studies that indicate that ILs based on Ampicillin could reverse resistance in some bacteria. The ILs produced in this work were synthetized by the neutralization method described in Ferraz et. al. [2] Ampicillin anion was combined with the following organic cations 1-ethyl-3-methylimidazolium, [EMIM]; 1-hydroxy-ethyl-3-methylimidazolium, [C2OHMIM]; choline, [cholin]; tetraethylammonium, [TEA]; cetylpyridinium, [C16pyr] and trihexyltetradecylphosphonium, [P6,6,6,14]. Amphotericin B was combined with [C16pyr], [cholin] and 1-metohyethyl-3-methylimidazolium, [C3OMIM]. The ILs-APIs based on ampicillin[2] were tested against sensitive Gram-negative bacteria Escherichia coli ATCC 25922 and Klebsiella pneumonia (clinical isolated), as well as on Gram positive Staphylococcus Aureus ATCC 25923, Staphylococcus epidermidis and Enterococcus faecalis. The arising resistance developed by bacteria to antibiotics is a serious public health threat and needs new and urgent measures. We study the bacterial activity of these compounds against a panel of resistant bacteria (clinical isolated strains): E. coli CTX M9, E. coli TEM CTX M9, E. coli TEM1, E. coli CTX M2, E. coli AmpC Mox2. In this work we demonstrate that is possible to produce ILs from anti-bacterial and anti-fungal compounds. We show here that the new ILs can reverse the bacteria resistance. With the careful choice of the organic cation, it is possible to create important biological and physic-chemical properties. This work also shows that the ion-pair is fundamental in ampicillin mechanism of action.

La médecine indigène comme instrument normatif social: l’exemple du corps malade navajo

La médecine traditionnelle indigène peut parfois se poser comme un instrument normatif désignant le malade comme celui qui transgresse l‘ordre établi par les ancêtres sacrés et permet à la maladie d‘advenir. Un tiers malveillant ou un sorcier peuvent également être les causes du désordre physiologique et moral du corps social communautaire. L‘étiologie navajo repose sur deux phénomènes : l‘existence de sociosomas (troubles liés à une mauvaise relation à l‘entourage) et de mouvements d‘exclusion ou d‘inclusion du corps étranger, de la conduite déviante. L‘étude de la figure du malade dans les mythes soulignera l‘aspect normatif des thérapeutiques navajo. Enfin, une réflexion sur la justification idéologique de l‘intégration des pratiques ancestrales au protocole de soin montrera dans quelle mesure la collaboration entre praticiens traditionnels et personnels de santé contribue à stigmatiser le malade comme l‘épitome de toutes les déviances : par rapport à la tradition mais aussi au modèle social dominant.

Sensors for the detection and quantification of bacterial contamination in water for human use

The deterioration of water quality by Cyanobacteria cause outbreaks and epidemics associated with harmful diseases in Humans and animals because of the toxins that they release. Microcystin-LR is one of the hepatotoxins most widely studied and the World Health Organization, recommend a maximum value of 1mgL 1 in drinking water. Highly specific recognition molecules, such as molecular imprinted polymers are developed to quantify microcystins in waters for human use and shown to be of great potential in the analysis of these kinds of samples. The obtained results were auspicious, the detection limit found, 1.5mgL 1, being of the same order of magnitude as the guideline limit recommended by the WHO. This technology is very promising because the sensors are stable and specific, and the technology is inexpensive and allows for rapid on-site monitoring.

Fractional dynamics and MDS visualization of earthquake phenomena

This paper analyses earthquake data in the perspective of dynamical systems and fractional calculus (FC). This new standpoint uses Multidimensional Scaling (MDS) as a powerful clustering and visualization tool. FC extends the concepts of integrals and derivatives to non-integer and complex orders. MDS is a technique that produces spatial or geometric representations of complex objects, such that those objects that are perceived to be similar in some sense are placed on the MDS maps forming clusters. In this study, over three million seismic occurrences, covering the period from January 1, 1904 up to March 14, 2012 are analysed. The events are characterized by their magnitude and spatiotemporal distributions and are divided into fifty groups, according to the Flinn–Engdahl (F–E) seismic regions of Earth. Several correlation indices are proposed to quantify the similarities among regions. MDS maps are proven as an intuitive and useful visual representation of the complex relationships that are present among seismic events, which may not be perceived on traditional geographic maps. Therefore, MDS constitutes a valid alternative to classic visualization tools for understanding the global behaviour of earthquakes.

Power law and entropy analysis of catastrophic phenomena

Catastrophic events, such as wars and terrorist attacks, tornadoes and hurricanes, earthquakes, tsunamis, floods and landslides, are always accompanied by a large number of casualties. The size distribution of these casualties has separately been shown to follow approximate power law (PL) distributions. In this paper, we analyze the statistical distributions of the number of victims of catastrophic phenomena, in particular, terrorism, and find double PL behavior. This means that the data sets are better approximated by two PLs instead of a single one. We plot the PL parameters, corresponding to several events, and observe an interesting pattern in the charts, where the lines that connect each pair of points defining the double PLs are almost parallel to each other. A complementary data analysis is performed by means of the computation of the entropy. The results reveal relationships hidden in the data that may trigger a future comprehensive explanation of this type of phenomena.

Does Pro12Ala polymorphism enhance the physiological role of PPARy2?

Obesity and type 2 diabetes mellitus (T2D) are two major public health problems that have motivated the scientific community to investigate the high contribution of genetic factors to these disorders. The peroxisome proliferator activated by gamma 2 (PPARy2) plays an important role in the lipid metabolism. Since PPARy2 is expressed mainly in adipose tissue, a moderate reduction of its activity influences the sensitivity to insulin, diabetes, and other metabolic parameters. The present study aims to contribute to the elucidation of the impact of the Pro12Ala polymorphism associated with T2D and obesity through a meta-analysis study of the literature that included approximately 11500 individuals, from which 3870 were obese and 7625 were diabetic. Statistical evidence supports protective effect in T2D of polymorphism Pro12Ala of PPARy2 (OR = 0.702 with 95% CI: 0.622; 0.791, P<0.01). Conversely the same polymorphism Pro12Ala of PPARy2 seems to favor obesity since 1.196 more chance than nonobese was found (OR = 1.196 with 95% CI: 1.009; 1.417,P<0.004). Our results suggest that Pro12Ala polymorphism enhances both adipogenic and antidiabetogenic physiological role of PPARy. Does Pro12Ala polymorphism represent an evolutionary step towards the stabilization of the molecular function of PPARy transcription factor signaling pathway?

Dynamic analysis of earthquake phenomena by means of pseudo phase plane

This paper analyses earthquake data in the perspective of dynamical systems and its Pseudo Phase Plane representation. The seismic data is collected from the Bulletin of the International Seismological Centre. The geological events are characterised by their magnitude and geographical location and described by means of time series of sequences of Dirac impulses. Fifty groups of data series are considered, according to the Flinn-Engdahl seismic regions of Earth. For each region, Pearson’s correlation coefficient is used to find the optimal time delay for reconstructing the Pseudo Phase Plane. The Pseudo Phase Plane plots are then analysed and characterised.

A review of power laws in real life phenomena

Power law distributions, also known as heavy tail distributions, model distinct real life phenomena in the areas of biology, demography, computer science, economics, information theory, language, and astronomy, amongst others. In this paper, it is presented a review of the literature having in mind applications and possible explanations for the use of power laws in real phenomena. We also unravel some controversies around power laws.

Fractional order inductive phenomena based on the skin effect

The Maxwell equations play a fundamental role in the electromagnetic theory and lead to models useful in physics and engineering. This formalism involves integer-order differential calculus, but the electromagnetic diffusion points towards the adoption of a fractional calculus approach. This study addresses the skin effect and develops a new method for implementing fractional-order inductive elements. Two genetic algorithms are adopted, one for the system numerical evaluation and another for the parameter identification, both with good results.

Electrical skin phenomena: a fractional calculus analysis

The internal impedance of a wire is the function of the frequency. In a conductor, where the conductivity is sufficiently high, the displacement current density can be neglected. In this case, the conduction current density is given by the product of the electric field and the conductance. One of the aspects of the high-frequency effects is the skin effect (SE). The fundamental problem with SE is it attenuates the higher frequency components of a signal.

Filtering method in backlash phenomena analysis

The behavior of robotic manipulators with backlash is analyzed. Based on the pseudo-phase plane two indices are proposed to evaluate the backlash effect upon the robotic system: the root mean square error and the fractal dimension. For the dynamical analysis the noisy signals captured from the system are filtered through wavelets. Several tests are developed that demonstrate the coherence of the results.

Performance of fractional PID algorithms controlling nonlinear systems with saturation and backlash phenomena

The development of fractional-order controllers is currently one of the most promising fields of research. However, most of the work in this area addresses the case of linear systems. This paper reports on the analysis of fractional-order control of nonlinear systems. The performance of discrete fractional-order PID controllers in the presence of several nonlinearities is discussed. Some results are provided that indicate the superior robustness of such algorithms.

Multidimensional scaling visualization of earthquake phenomena

Earthquakes are associated with negative events, such as large number of casualties, destruction of buildings and infrastructures, or emergence of tsunamis. In this paper, we apply the Multidimensional Scaling (MDS) analysis to earthquake data. MDS is a set of techniques that produce spatial or geometric representations of complex objects, such that, objects perceived to be similar/distinct in some sense are placed nearby/distant on the MDS maps. The interpretation of the charts is based on the resulting clusters since MDS produces a different locus for each similarity measure. In this study, over three million seismic occurrences, covering the period from January 1, 1904 up to March 14, 2012 are analyzed. The events, characterized by their magnitude and spatiotemporal distributions, are divided into groups, either according to the Flinn–Engdahl seismic regions of Earth or using a rectangular grid based in latitude and longitude coordinates. Space-time and Space-frequency correlation indices are proposed to quantify the similarities among events. MDS has the advantage of avoiding sensitivity to the non-uniform spatial distribution of seismic data, resulting from poorly instrumented areas, and is well suited for accessing dynamics of complex systems. MDS maps are proven as an intuitive and useful visual representation of the complex relationships that are present among seismic events, which may not be perceived on traditional geographic maps. Therefore, MDS constitutes a valid alternative to classic visualization tools, for understanding the global behavior of earthquakes.