Excitotoxicity, a major hallmark of neurodegeneration associated with cerebral ischemia, is a result of accumulation of extracellular glutamate. This excess glutamate leads to hyperactivation of glutamate receptors such as the N-methyl-D-asparate (NMDA) receptors (NMDARs) following the activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor (AMPARs). Excessive activation of NMDARs causes an influx of calcium, which can eventually activate apoptotic pathways and lead to death of neurons. Regulation of NMDAR subunit composition, localization, surface expression, and activity can balance cell survival via activation of either pro-death or pro-survival pathways after a course of an ischemic insult. Specifically, phosphorylation of different NMDAR subunits defines their activity and downstream signaling pathways. NMDARs are phosphorylated by multiple kinases and dephosphorylated by different phosphatases. Besides phosphatases and kinases, per se, phosphorylation of synaptic proteins that regulate kinase or phosphatase targeting and activity also mediate NMDAR phosphorylation. Spinophilin, a major synaptic scaffolding and protein phosphatase 1 (PP1) targeting protein, mediates substrate phosphorylation via its ability to bind PP1. Our studies focus on delineating the role of spinophilin in the regulation of phosphorylation and function of the GluN2B subunit of the NMDA receptor as well as the role of spinophilin in modulating glutamate-induced neurotoxicity. Interestingly, our data demonstrate that spinophilin sequesters PP1 away from GluN2B thereby enhancing phosphorylation of GluN2B at Ser-1284. These changes impact GluN2B protein interactions, subcellular localization, and surface expression, leading to alterations in the amount of calcium entering the neuron via GluN2B-containing NMDARs. Our data show that spinophilin biphasically regulates GluN2B function. Specifically, Ser-1284 phosphorylation enhances calcium influx through GluN2B containing NMDA receptors, but spinophilin leads to dramatic decreases in the surface expression of the receptor independent of Ser-1284 phosphorylation. Moreover, in spinophilin knockout mice, we observe less PP1 binding to GluN2B and less phosphorylation of Ser-1284, but more surface expression of GluN2B and greater levels of caspase activity. Together, these observations suggest a potential neuroprotective role for spinophilin by decreasing GluN2B-containing NMDA receptor-dependent surface expression and thereby decreasing intracellular calcium and neuronal cell death.

Adenylate cyclase (CyaA, ACT) toxin is one of the major virulence factors of Bordetella pertussis. Although CyaA binds to many types of membranes, it is assumed that the integrin CD11b/CD18 is its receptor which is expressed on the surface of myeloid cells. CyaA belongs to the family of RTX toxin-hemolysins. CyaA acts on the host cells by two independent activities. One of them is the conversion of ATP to cyclic AMP, which is catalyzed by adenylate cyclase (AC) domain after its translocation into the cytosol of the host cell, which leads to the entry of calcium cations into the host cell. Translocation is probably initiated by interaction of CyaA monomer with the target membrane. The second activity is the formation of CyaA channel selective for cations, which probably causes colloid osmotic lysis of target cells. The channel forming activity is provided by RTX hemolysin domain which most probably forms oligomers, although it was found that CyaA as a monomer causes leakage of potassium cations from the host cell. It is also not clear whether the oligomerization of CyaA would occur in solution, or after interaction with the host membrane. The aim of this study was to examine the flow of sodium ions on the membrane of murine macrophages J774A.1, which express integrin CD11b/CD18 on their surface....

Vascular resistance is mainly determined by the contraction of vascular smooth muscle (VSM), which is regulated by the phosphorylation of myosin light chain (MLC). VSM contraction is initiated by calcium influx into the VSM cells, which is mediated by transient receptor potential (TRP) channels and L-type voltage- dependent calcium channels (L-VDCC). On the other hand, calcium sensitization is a mechanism enhancing vascular contractile response at a given level of intracellular calcium by RhoA/Rho kinase pathway-mediated inhibition of myosin light chain phosphatase. In this thesis I present the data about i) the role of TRP channels in the mechanisms of vascular smooth muscle contraction, ii) enhanced contractility of arteries from spontaneously hypertensive rats (SHR), and iii) the differences in contraction of arteries from normotensive and hypertensive rats related to the role of RhoA/Rho kinase pathway in three types of experimental hypertension (SHR, Ren-2 transgenic rats and salt-sensitive Dahl rats). In the study concerning TRP channels, I compared the effects of three commonly used non-selective TRP channels inhibitors (2-APB, SKF-96365, FFA) on isolated arteries. Among them 2-APB was the most interesting because the observed inhibitory effects of 2-APB were dependent on the type of...

En la actualidad, los entornos virtuales son una tecnología en constante evolución. Dicha evolución se relacionada en diferentes áreas de estudio, explayándose desde el área medica hasta el área de la arquitectura, siendo esta última, conformada por usualmente sistemas de simulación respecto a evacuaciones, flujos o mediciones de entornos.  No obstante, los sistemas existentes presentan cierto grado de complejidad en la interacción con el usuario, puesto que, la mayoría de estos cuenta con una interfaz de programación, en donde el usuario es el encargado de programar tanto los entornos, como el comportamiento del flujo de agentes simulados. Generando un nivel de complejidad en estos, pues desvía el conocimiento nato de los estudiantes de arquitectura, al nivel de aprender diferentes lenguajes de programación con el fin de poder simular sus entornos y el comportamiento de personas en estos.     Por otro lado, estos sistemas, a su vez, se centran en movimientos ya establecidos, en donde el usuario no aprecia o no tiene idea de cómo el recorrido realizado por el agente es el óptimo respecto otros existentes. Siendo este definido por el sistema y no por el usuario.   En consecuencia, como resultado de investigación, se propone un software de simulación, edición y análisis de afluencia de personas en edificaciones de alto tránsito para mejorar la calidad de aprendizaje de los estudiantes de arquitectura. Desarrollando el presente trabajo, en etapas. En donde, la primera etapa, consiste en definir el alcance del proyecto, necesidades y objetivos, así como oportunidades de negocio. En la segunda etapa, se listarán los framework necesarios, de la cuales se explicarán sus ventajas y desventajas correspondientes a las demandas de nuestra simulación. Y, en tercer lugar, tras haber seleccionado alguno, se procederá con la propuesta de investigación, así como su comparativo técnico con otras soluciones.  Finalmente, se tratará como problemática: “La necesidad de una herramienta de simulación de fácil uso, bajo costo, mantenimiento y libre de lenguajes de programación; respecto la afluencia de personas.” / Today the simulation of real environments is a process of constant evolution. This extends from research fields in medicine to architecture being in the latter a simulation system regarding evacuations flows or measurements of environments. However, the existing systems have given much to talk about in this context since most of them have a programming interface where the user oversees programming both the environments and the flow behavior of simulated agents. Generating a level of complexity in these as it diverts the natural knowledge of architecture students at the level of learning different programming languages ​​to be able to simulate their environments and the behavior of people in them. On the other hand, these systems in turn focus on already established movements where the user does not appreciate or has no idea of ​​how the route made by the agent is optimal compared to other existing ones. Being this defined by the system and not by the user. Consequently, because of research a software for the simulation editing and analysis of the influx of people in high-traffic buildings is proposed to improve the quality of learning of architecture students. Developing this work in stages. Where the first stage consists of defining the scope of the project needs and objectives as well as business opportunities. In the second stage the necessary frameworks will be listed of which their advantages and disadvantages corresponding to the demands of our simulation will be explained and thirdly after having selected one we will proceed with the research proposal as well as its technical comparison with other solutions. Finally, the following will be treated as problematic: “The need for a simulation tool that is easy to use low in cost, maintenance and free of programming languages regarding the influx of people. / Tesis

The subcellular mechanism and site of action of linopirdine or DuP 996 (3,3‐bis(4‐pyridinylmethyl)‐1‐phenylindolin‐2‐one) was investigated at the frog neuromuscular junction, using miniature endplate potential (m.e.p.p.) counts and a new method for obtaining unbiased estimates of n (number of functional release sites), p (probability of release), and varsp (spatial variance in p). DuP 996 produced an increase in m (no. of quanta released), which was due to an increase in n and p. The increase in m was concentration‐dependent over a range of 0.1–100 μm and completely reversible with 15 min of wash. There was a saturation in the increase in p, but not in the increase in m and n, for [DuP 996] >10 μm. By contrast, there was no major change in varsp. Block of presynaptic Na+‐ and Ca2+‐channels with 3 μm tetrodotoxin and 1.8 mm Co2+prevented the m.e.p.p. frequency increase to DuP 996, and this effect was completely reversed by washing. Application of the neuronal Ca2+‐channel blocker, ω‐conotoxin GVIA (1 μm) brought about a rapid and profound decrease in the m.e.p.p. frequency increase produced by DuP 996. The effect of the toxin was not reversed by prolonged washing. Block of voltage‐gated K+‐channels with 100 μm 4‐aminopyridine (4‐AP) resulted in only a small (28%) increase in m. The combination of 4‐AP (100 μm) and DuP 996 (10 μm) produced an increase in m (189%) which was much greater than the sum of the responses to each agent alone. This increase in m was due solely to an increase in n, as p and varsp were unchanged. For [DuP 996] up to 100 μm, there was no apparent change in the mean size, amplitude distribution, or time course of m.e.p.ps, signifying that it had no anticholinesterase activity. It is concluded that DuP 996 increases the release of quantal transmitter but not the postsynaptic response to the quanta. This appears to involve an effect at the nerve terminal membrane, most likely an increase in Ca2+‐conductance, and not an action to block K+‐conductance or to release Ca2+from intraterminal organelles. 1994 British Pharmacological Society

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With the increasing demand for renewable energy, solar cells have become a crucial technology in meeting this need. Optimizing the placement of solar cells is essential and can be achieved by tracking their performance data. This project's goal was to develop an interface for collecting primarily solar cell-related data, although it is versatile enough to handle any type of data. The report details the sensors and components used in the standard interface. The final product is not strictly a transmitter or receiver, but includes a piece of breadboard allowing for the implementation of various circuits. Additionally, the practical aspects of data collection using a Raspberry Pi and database services are discussed. The completed system features transmitter and receiver circuits, which can be expanded into a larger mesh network as needed.

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TRPM4, un canal cationique non-sélective activé par le Ca2+ intracellulaire, est un acteur moléculaire important impliqué de la régulation du signal calcique et l’activation des lymphocytes T conventionnels mais son rôle dans la fonction des lymphocytes T régulateurs (Tregs Foxp3+) reste inconnu. Dans un modèle de souris transgéniques dans lequel le gène Trpm4 a été sélectivement invalidé dans la population des Tregs Foxp3+ (souris Foxp3(YFP)Cre+Trpm4flox/flox), nous avons démontré dans différents modèles in vivo d’inflammation aiguë et chronique que TRPM4 contrôle la fonction suppressive et la mort de ces cellules. Dans le modèle de fibrosarcome induit par le méthylcholanthrène (3-MCA) ou implanté (modèle MCA205), dans lequel le rôle des Tregs est documenté, l’absence de fonction de TRPM4 induit une diminution significative de l’incidence et de la croissance tumorale. Dans l’environnent inflammatoire chronique et hypoxique de ces tumeurs, l’expression de TRPM4 protège les Tregs infiltrant la tumeur de la mort cellulaire induit par l’ATP extracellulaire et stimule ainsi le développent et la progression tumorale. L’absence d’expression de TRPM4 dans les Tregs stimule la réponse anti-tumorale médiée par l’IFNg et induit la régression des tumeurs. En conclusion, en inhibant l’entrée de Ca2+ extracellulaire, TRPM4 régule négativement les fonctions suppressives des Tregs et protège ces cellules de la mort cellulaire induite par l’activation. / TRPM4, a Ca2+-activated non-selective cation ion channel is an important regulator of Ca2+ signaling and cell activation in conventional T cells, but its role in Foxp3+ Tregs function remains unknown. Using a model in which Trpm4 gene was selectively invalidated in Foxp3+ Tregs population (Foxp3(YFP)Cre+Trpm4flox/flox mice) we have shown in different in vivo models of acute and chronic inflammation that TRPM4 is an important regulator of Tregs functions and survival. In a model of primary carcinogenesis induced by methylcholantrene (3-MCA) or implanted fibrosarcoma (MCA205 model), in which Tregs role has been documented, lack of TRPM4 expression and function induced significantly decreased incidence and tumor growth. We found that within chronic inflammatory and hypoxic tumor microenvironment, TRPM4 protected Tregs from ATP-induced cell death and therefore promoted tumor initiation and progression. In contrast, TRPM4 deficiency in Tregs favored IFN-g-mediated spontaneous anti-tumor immune response. Thus, through inhibiting Ca2+ influx, TRPM4 acts as a negative modulator of Tregs suppressive functions and protects Tregs from activation-induced cell death.