Dynamical properties of model communication networks

We study the dynamical properties of a collection of models for communication processes, characterized by a single parameter $\xi$ representing the relation between information load of the nodes and its ability to deliver this information. The critical transition to congestion reported so far occurs only for $\xi=1$. This case is well analyzed for different network topologies. We focus of the properties of the order parameter, the susceptibility and the time correlations when approaching the critical point. For $\xi<1$ no transition to congestion is observed but it remains a cross-over from a low-density to a high-density state. For $\xi>1$ the transition to congestion is discontinuous and congestion nuclei arise.Comment: 8 pages, 8 figure

Imbalance of p75(NTR)/TrkB protein expression in Huntington's disease: Implication for neuroprotective therapies

Neuroprotective therapies based on brain-derived neurotrophic factor (BDNF) administration have been proposed for Huntington's disease (HD) treatment. However, our group has recently reported reduced levels of TrkB in HD mouse models and HD human brain suggesting that besides a decrease on BDNF levels a reduction of TrkB expression could also contribute to diminished neurotrophic support in HD. BDNF can also bind to p75 neurotrophin receptor (p75(NTR)) modulating TrkB signaling. Therefore, in this study we have analyzed the levels of p75(NTR) in several HD models, as well as in HD human brain. Our data demonstrates a p75(NTR)/TrkB imbalance in the striatum of two different HD mouse models, Hdh(Q111/111) homozygous knockin mice and R6/1 mice that was also manifested in the putamen of HD patients. The imbalance between TrkB and p75(NTR) levels in a HD cellular model did not affect BDNF-mediated TrkB activation of prosurvival pathways but induced activation of apoptotic cascades as demonstrated by increased JNK phosphorylation. Moreover, BDNF failed to protect mutant huntingtin striatal cells transfected with p75(NTR) against NMDA-mediated excitotoxicity, which was associated with decreased Akt phosphorylation. Interestingly, lack of Akt activation following BDNF and NMDA treatment correlated with increased PP1 levels. Accordingly, pharmacological inhibition of PP1 by okadaic acid (OA) prevented mutant huntingtin striatal cell death induced by NMDA and BDNF. Altogether, our findings demonstrate that the p75(NTR)/TrkB imbalance induced by mutant huntingtin in striatal cells associated with the aberrant activity of PP1 disturbs BDNF neuroprotection likely contributing to increasing striatal vulnerability in HD. On the basis of this data we hypothesize that normalization of p75(NTR) and/or TrkB expression or their signaling will improve BDNF neuroprotective therapies in HD. Cell Death and Disease (2013) 4, e595; doi:10.1038/cddis.2013.116; published online 18 April 201

«Les branques entrellaçades»: un motiu del folklore verbal i els gèneres mixtos

L’article aborda comparativament un motiu de l’art verbal i alhora la seva interacció amb un problema general de l’estudi del folklore: el dels gèneres mixtos i llur significació. El motiu en qüestió és designat «Twining branches» (E631.0.1) en l’índex de Thompson. S’assenyala l’eventual precedent clàssic ovidià i se’n considera la presència en romanços de la tradició romànica peninsular i en balades angloamericanes, gèneres versificats. Si comparteixen el motiu de les branques entrellaçades, difereixen en aspectes funcionals i argumentals. S’aporta una narració oral beduïna del desert Líbic que conté l’argument i el motiu. Aquest text oral és un gènere mixt: hi coexisteixen prosa i vers (prosimetrum). S’analitzen diferències funcionals respecte als textos anteriors i se’n vincula l’especificitat a la naturalesa de l’ordre social en la societat beduïna, a la ideologia que hi és hegemònica, a la identitat ètnica i a la cultura verbal beduïna arabitzada. S’interpreta el gènere mixt en funció de conceptes desenvolupats a partir de la poètica jakobsoniana i, sobretot, en funció del context en què es produeix, això és, de l’especificitat històrica i d’una interpretació èmica, la qual ens permet accedir a la significació que vehicula la juxtaposició de prosa i vers en un context d’actuació específic

E2F1, a Novel Regulator of Metabolism.

In the past years, several lines of evidence have shown that cell cycle regulatory proteins also can modulate metabolic processes. The transcription factor E2F1 is a central player involved in cell cycle progression, DNA-damage response, and apoptosis. Its crucial role in the control of cell fate has been extensively studied and reviewed before; however, here, we focus on the participation of E2F1 in the regulation of metabolism. We summarize recent findings about the cell cycle-independent roles of E2F1 in various tissues that contribute to global metabolic homeostasis and highlight that E2F1 activity is increased during obesity. Finally, coming back to the pivotal role of E2F1 in cancer development, we discuss how E2F1 links cell cycle progression with different metabolic adaptations required for cell growth and survival

Factors controlling the geochemical composition of Limnopolar Lake sediments (Byers Peninsula, Livingston Island, South Shetland Island, Antarctica) during the last ca. 1600 years

We sampled a short (57 cm) sediment core in Limnopolar Lake (Byers Peninsula, Livingston Island, South Shetland Islands), which spans the last ca. 1600 years. The core was sectioned at high resolution and analyzed for elemental and mineralogical composition, and scanning electron microscope and energy dispersive X-ray spectrometer (SEM-EDS) analysis of glass mineral particles in selected samples. The chemical record was characterized by a contrasted pattern of layers with high Ca, Ti, Zr, and Sr concentrations and layers with higher concentrations of K and Rb. The former were also enriched in plagioclase and, occasionally, in zeolites, while the latter were relatively enriched in 2 : 1 phyllosilicates and quartz. This was interpreted as reflecting the abundance of volcaniclastic material (Ca rich) versus Jurassic–Lower Cretaceous marine sediments (K rich) – the dominant geological material in the lake catchment. SEM-EDS analysis revealed the presence of abundant volcanic shards in the Ca-rich layers, pointing to tephras most probably related to the activity of Deception Island volcano (located 30 km to the SE). The ages of four main peaks of volcanic-rich material (AD ca. 1840–1860 for L1, AD ca. 1570–1650 for L2, AD ca. 1450–1470 for L3, and AD ca. 1300 for L4) matched reasonably well the age of tephra layers (AP1 to AP3) previously identified in lakes of Byers Peninsula. Some of the analyzed metals (Fe, Mn, Cu, and Cr) showed enrichments in the most recent tephra layer (L1), suggesting relative changes in the composition of the tephras as found in previous investigations. No evidence of significant human impact on the cycles of most trace metals (Cu, Zn, Pb) was found, probably due to the remote location of Livingston Island and the modest research infrastructures; local contamination was found by other researchers in soils, waters and marine sediments on areas with large, permanent research stations. Chromium is the only metal showing a steady enrichment in the last 200 years, but this cannot be directly attributed to anthropogenic pollution since recent research supports the interpretation that climatic variability (reduced moisture content and increased wind intensity) may have resulted in enhanced fluxes of mineral dust and trace elements (Cr among them) to Antarctica. At the same time, some features of the chemical record suggest that climate may have also played a role in the cycling of the elements, but further research is needed to identify the underlying mechanisms.This work was partially supported by projects CGL2010-20672 and REN2000-0345-ANT (Spanish Ministerio de Ciencia e Innovación), POL2006-06635/CGL (Spanish Ministerio de Educación y Cultura), and 10PXIB200182PR (Dirección Xeral de I+D, Xunta de Galicia).Peer reviewe

Índice de Liam: prueba física funcional

Made very important test (Liam) in the medical students in Medical Faculty in Artemisa city, because with this examination proof the functional and physical conditions before and after training. All students after training received best results than before. It is very important to because the students obtained some abilities in this subject when will be doctorsSe realizó un análisis de la prueba funcional de Liam en un grupo de estudiantes de 2do año de Medicina de Artemisa con el objetivo de valorar el grado de aptitud cardiovascular y el nivel de entrenamiento de este grupo, donde se obtuvo que la mayoría de los estudiantes el 77,8% estaba apto físicamente y solo dos para un 22,2% se encontraba en la categoría de pobre en la prueba que se realizó al inicio del curso .Esta prueba es de gran utilidad en nuestra formación como futuro Medico Generales Integrales y sobre todo que es muy fácil su proceder y lo podemos aplicar en área de salud con nuestros pacientes ,una vez graduados como médicos .En el mes de Abril después de seis meses de práctica sistemática de ejercicios físicos todos los estudiantes mejoraron de forma considerable su aptitud cardiovascular y el nivel de entrenamiento a las categorías de muy bien y bie

Sequence Context Influences the Structure and Aggregation Behavior of a PolyQ Tract

Expansions of polyglutamine (polyQ) tracts in nine different proteins cause a family of neurodegenerative disorders called polyQ diseases. Because polyQ tracts are potential therapeutic targets for these pathologies there is great interest in characterizing the conformations that they adopt and in understanding how their aggregation behavior is influenced by the sequences flanking them. We used solution NMR to study at single-residue resolution a 156-residue proteolytic fragment of the androgen receptor that contains a polyQ tract associated with the disease spinobulbar muscular atrophy, also known as Kennedy disease. Our findings indicate that a Leu-rich region preceding the polyQ tract causes it to become α-helical and appears to protect the protein against aggregation, which represents a new, to our knowledge, mechanism by which sequence context can minimize the deleterious properties of these repetitive regions. Our results have implications for drug discovery for polyQ diseases because they suggest that the residues flanking these repetitive sequences may represent viable therapeutic targets

Consensus guidelines for the management of radiation dermatitis and coexisting acne-like rash in patients receiving radiotherapy plus EGFR inhibitors for the treatment of squamous cell carcinoma of the head and neck

Background: Radiation dermatitis occurs to some degree in most patients receiving radiotherapy, with or without chemotherapy. Patients with squamous cell carcinoma of the head and neck (SCCHN) who receive radiotherapy in combination with epidermal growth factor receptor (EGFR) inhibitors, such as cetuximab, may develop a characteristic acne-like rash in addition to dermatitis. Design: An advisory board of 11 experienced radiation oncologists, medical oncologists and dermatologists discussed the management options for skin reactions in patients receiving EGFR inhibitors and radiotherapy for SCCHN. Skin toxicity was categorised according to the National Cancer Institute—Common Terminology Criteria for Adverse Events (version 3) grading. Results: Both general and grade-specific approaches for the management of dermatitis in this patient group are presented. It was concluded that where EGFR inhibitor-related acne-like rash and dermatitis coexist within irradiated fields, management should be based on the grade of dermatitis: for grade 1 (or no dermatitis), treatment recommendations for EGFR-related acne-like rash outside irradiated fields should be followed; for grades 2 and above, treatment recommendations for dermatitis were proposed. Conclusions: This paper presents comprehensive consensus guidelines for the treatment of dermatitis in patients with SCCHN receiving EGFR inhibitors in combination with radiotherap

Infiltration of a biocompatible gel for the treatment of interdigital exostoses: A cadaveric study

Antecedentes. La exóstosis interdigital es una patología común que se presenta con frecuencia en las consultas de podología. A pesar del alto grado de incidencia es una entidad clínica muy poco estudiada. En la actualidad, los tratamientos propuestos para resolver esta patología son el tratamiento conservador mediante ortesis de silicona y el tratamiento quirúrgico consistente en la resección de la exostosis. Consideramos necesario otra alternativa de tratamiento que mejore la actividad diaria de los pacientes que presenten esta patología. Material y Métodos. Se procedió a la infiltración de un gel biocompatible en cadáver para simular de la forma más idónea posible la posterior aplicación clínica en pacientes. Se seleccionaron 10 pies de cadáver fresco, no formolado, con presencia de exostois a los que se realizó la infiltración del gel biocompatible siguiendo las instrucciones del fabricante. Resultados. Se observaron los siguientes aspectos: relación cantidad de producto/dimensiones obtenidas, edad de los especímenes, sexo, localización exostosis, cantidad de producto infiltrado, tipo de aguja, forma de infiltración, facilidad de la infiltración y distribución del producto. Conclusiones. La valoración de la técnica es positiva en el 100% de los casos, demostrando que el producto permanece in situ en la localización prevista, lo que nos hace concluir que puede ser un tratamiento válido para la exostosis interdigital.Precedents. Interdigital exostosis is a common pathology in podiatric surgery. Despite the rates of incidence, little has been researched on this clinical entity. Currently proposed treatments are: conservative treatment with silicone orthosis, and surgical treatment based on resection of exostosis. An alternative treatment to improve daily activity of patients with this pathology has been considered necessary. Material and Methods. Bio compatible gel was injected in a dead body in order to experiment and simulate the subsequent clinical application in patients. We selected 10 feet of fresh dead body, non-preserved in formaldehyde, with presence of exostosis, to which the bio compatible gel was injected following the established protocol and instructions provided by the manufacturer. Results. Aspects observed: relationship quantity of product / dimensions obtained, age of specimen, gender, location of exostosis, quantity of product injected, type of needle, injection procedure, ease of injection and allocation of product. Conclusion. The method is assessed as positive in 100% of studied cases, as the product remains in the predicted area, therefore we conclude that it is a suitable treatment for the interdigital exostosis