Motivos filo-esópicos en el Midrás. Fábulas y anécdotas de rabinos en Levítico Rabbá 22,4

The text of LvR 22:4 collects some fables and the Rabbis’ vital experiences, bringing them together harmoniously. These stories share the same context and theme, because they both are related to the observation of the nature and especially to the world of the animals. Although it is not possible to ascertain whether the origin of the fables lies in the Aesopian tradition, clear parallels are observed between the images of the Midrash and those of the Roman-Hellenistic collections that have come down to us. Therefore, the aim of this study is twofold: on the one hand, to analyse the fables and their links with the Aesopian motifs and, on the other, to offer a valuable example of how these tales are perfectly combined with the Sages’ anecdotes by means of the Rabbinic literary devices.El pasaje de LvR 22,4 combina armoniosamente una serie de fábulas con algunos episodios de la vida de ciertos rabinos. Estos relatos comparten un mismo contexto y una misma temática, ya que están relacionados con la observación de la naturaleza y sobre todo del mundo animal. Aunque no es posible afirmar con seguridad si el origen de las fábulas se halla en las tradiciones esópicas, se observan claros paralelos entre las imágenes del Midrás y las de las colecciones de época helenística-romana que han llegado hasta nuestros días. Por tanto, el presente estudio tiene una doble finalidad: por un lado, el análisis de las fábulas y su vinculación con los motivos esópicos y, por otro, ofrecer un valioso ejemplo de cómo se conjugan estos relatos con las anécdotas de los sabios a través de los recursos propios de la literatura rabínica

Negative feedback of extracellular ADP on ATP release in goldfish hepatocytes: A theoretical study

A mathematical model was built to account for the kinetic of extracellular ATP (ATPe) and extracellular ADP (ADPe) concentrations from goldfish hepatocytes exposed to hypotonicity. The model was based on previous experimental results on the time course of ATPe accumulation, ectoATPase activity, and cell viability [Pafundo et al., 2008]. The kinetic of ATPe is controlled by a lytic ATP flux, a non-lytic ATP flux, and ecto-ATPase activity, whereas ADPe kinetic is governed by a lytic ADP flux and both ecto-ATPase and ecto-ADPase activities. Non-lytic ATPe efflux was included as a diffusion equation modulated by ATPe activation (positive feedback) and ADPe inhibition (negative feedback). The model yielded physically meaningful and stable steady-state solutions, was able to fit the experimental time evolution of ATPe and simulated the concomitant kinetic of ADPe. According to the model during the first minute of hypotonicity the concentration of ATPe is mainly governed by both lytic and non-lytic ATP efflux, with almost no contribution from ecto-ATPase activity. Later on, ecto- ATPase activity becomes important in defining the time dependent decay of ATPe levels. ADPe inhibition of the non-lytic ATP efflux was strong, whereas ATPe activation was minimal. Finally, the model was able to predict the consequences of partial inhibition of ecto-ATPase activity on the ATPe kinetic, thus emulating the exposure of goldfish cells to hypotonic medium in the presence of the ATP analog AMP-PCP. The model predicts this analog to both inhibit ectoATPase activity and increase nonlytic ATP release.Fil: Chara, Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física de Líquidos y Sistemas Biológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física de Líquidos y Sistemas Biológicos; ArgentinaFil: Pafundo, Diego Esteban. Univeristy of Pittsburgh. School of Medicine; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Schwarzbaum, Pablo Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentin

And We cast upon his throne a mere body: A Historiographical Reading of Q. 38:34

This paper focuses on Q. 38:34 from the perspective of early and medieval works of Islamic historiography and collections of tales of the prophets: the early tenth century works of 'Umara b. Wathima and Tabari, the eleventh century Tales of the Prophets by Tha'labi, the twelfth century folkloric collection of Kisa'i, along with Ibn 'Asakir's History of Damascus, the thirteenth century world history by Ibn al-Athir, and the fourteenth century historiographical work by Ibn Kathir. These various works are viewed not as any particular stage in the development of a genre, but as variations on a (Qur'anic) theme, and the avenue of medieval historiographers and storytellers is utilised as a bridge to explore various possible interpretations of the Qur'anic passage. Historiographers and storytellers provide us with an illustration of how lessons of admonition implied in the Qur'anic text were perceived in medieval Islamic society. They also, as will become clear, provide a picture of Solomon that is consistent with the Qur'anic figure as a whole

The broad range di- and trinucleotide exchanger SLC35B1 displays asymmetrical affinities for ATP transport across the ER membrane

In eukaryotic cells, uptake of cytosolic ATP into the endoplasmic reticulum (ER) lumen is critical for the proper functioning of chaperone proteins. The human transport protein SLC35B1 was recently postulated to mediate ATP/ADP exchange in the ER; however, the underlying molecular mechanisms mediating ATP uptake are not completely understood. Here, we extensively characterized the transport kinetics of human SLC35B1 expressed in yeast that was purified and reconstituted into liposomes. Using [α32P]ATP uptake assays, we tested the nucleotide concentration dependence of ATP/ADP exchange activity on both sides of the membrane. We found that the apparent affinities of SLC35B1 for ATP/ADP on the internal face were approximately 13 times higher than those on the external side. Because SLC35B1-containing liposomes were preferentially inside-out oriented, these results suggest a low-affinity external site and a high-affinity internal site in the ER. Three different experimental approaches indicated that ATP/ADP exchange by SLC35B1 was not strict, and that other di- and tri-nucleotides could act as suitable counter-substrates for ATP, although mononucleotides and nucleotide sugars were not transported. Finally, bioinformatic analysis and site-directed mutagenesis identified that conserved residues K117 and K120 from transmembrane helix 4 and K277 from transmembrane helix 9 play critical roles in transport. The fact that SLC35B1 can promote ATP transport in exchange for ADP or UDP suggest a more direct coupling between ATP import requirements and the need for eliminating ADP and UDP, which are generated as side products of reactions taking place in the ER-lumen.Fil: Schwarzbaum, Pablo Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Schachter, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Bredeston, Luis María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentin

Through the Lens of the ASD Self-Advocate

Participants will learn about developments in the area of self-advocacy, including the latest information on factors that promote self-advocacy, valuable, practical strategies and resources to assist individuals in becoming self-advocates, and identifying ways to develop advocacy skills. Using real life scenarios, this workshop will demonstrate the how to(s) when it comes to finding success and hope. This is an opportunity to listen to FBH residents talk about their journeys to becoming effective self-advocates

A biomimetic device combining microfluidics with nanotechnology allows studying the adhesion of erythrocytes to blood vessels

Erythrocytes under pathological conditions undergo eryptosis, a process characterized by biochemical and morphological changes such as phosphatidylserine (PS) exposure to the plasma membrane external layer. Eryptotic erythrocytes adhere to the endothelial cells (ECs), which may be important in the pathology of bacterial infections and congenital diseases like sickle cell disease. Externalized PS can bind to receptors expressed on ECs under pathological conditions. To understand the adhesion mechanism, we designed a device combining microfluidics with nanostructured surfaces to mimic the capillary architecture and the expression of adhesive molecules by the activated ECs. Microfluidic chips were prepared in PDMS using molds fabricated by photolithography. Nanostructured surfaces were synthesized by block copolymer lithography and consisted of a glass surface covered with 7 nm diameter gold nanoparticles (AuNPs), arranged in a quasi-hexagonal array. The microfluidic chip was adhered to the nanostructured surface by an O2 plasma treatment. The AuNPs were functionalized with a polyethylene glycol chain (PEG) that binds to the AuNPs by a thiol at one end and has a nitriloacetic group (NTA) at the other end. The NTA binds proteins expressing a His-Tag. The surface not occupied by AuNPs was covered with PLL-g-PEG. We corroborated the specific AuNPs functionalization by quartz microbalance and fluorescence microscopy using a GFP-His Tag. Then, we studied the erythrocytes adhesion to a device functionalized with Annexin V-His Tag at different flows. Two conditions that promote eryptosis, incubation at 50° C or treatment with ionomycin, significantly increased the adhesion of erythrocytes at flows up to 1.5 dyn/cm2, in comparison with untreated erythrocytes. However, eryptotic erythrocytes also showed adherence to a device functionalized with a PEG lacking NTA groups. This indicates that erythrocytes adhesion may not be mediated only by PS receptors. Future experiments will test the erythrocytes adhesion elicited by proteins usually expressed by the activated ECs.Fil: Saffioti, Nicolas Andres. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Leal Denis, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Herlax, Vanesa Silvana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Schwarzbaum, Pablo Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Pallarola, Diego Andres. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina20th Internaitional Congress of the INternational Union for Pure Applied Biophysics; 50th Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology; 45th Congress of Brazilian Biophysics Society anda 13th Brazilian Society on Nuclear Biosciences CongressBrasilSociedade Brasileira de Bioquímica e Biología Molecula

Dynamic regulation of cell volume and extracellular ATP of human erythrocytes

Introduction: The peptide mastoparan 7 (MST7) triggered in human erythrocytes (rbcs) the release of ATP and swelling. Since swelling is a well-known inducer of ATP release, and extracellular (ATPe), interacting with P (purinergic) receptors, can affect cell volume (Vr), we explored the dynamic regulation between Vr and ATPe. Methods and Treatments: We made a quantitative assessment of MST7-dependent kinetics of Vr and of [ATPe], both in the absence and presence of blockers of ATP efflux, swelling and P receptors. Results: In rbcs 10 μM MST7 promoted acute, strongly correlated changes in [ATPe] and Vr. Whereas MST7 induced increases of 10% in Vr and 190 nM in [ATPe], blocking swelling in a hyperosmotic medium + MST7 reduced [ATPe] by 40%. Pre-incubation of rbcs with 10 μM of either carbenoxolone or probenecid, two inhibitors of the ATP conduit pannexin 1, reduced [ATPe] by 40-50% and swelling by 40-60%, while in the presence of 80 U/mL apyrase, an ATPe scavenger, cell swelling was prevented. While exposure to 10 μM NF110, a blocker of ATP-P2X receptors mediating sodium influx, reduced [ATPe] by 48%, and swelling by 80%, incubation of cells in sodium free medium reduced swelling by 92%. Analysis and Discussion: Results were analyzed by means of a mathematical model where ATPe kinetics and Vr kinetics were mutually regulated. Model dependent fit to experimental data showed that, upon MST7 exposure, ATP efflux required a fast 1960-fold increase of ATP permeability, mediated by two kinetically different conduits, both of which were activated by swelling and inactivated by time. Both experimental and theoretical results suggest that, following MST7 exposure, ATP is released via two conduits, one of which is mediated by pannexin 1. The accumulated ATPe activates P2X receptors, followed by sodium influx, resulting in cell swelling, which in turn further activates ATP release. Thus swelling and P2X receptors constitute essential components of a positive feedback loop underlying ATP-induced ATP release of rbcs.Instituto de Física de Líquidos y Sistemas Biológico

Kinetics of Extracellular ATP from Goldfish Hepatocytes: A Lesson from Mathematical Modeling

In goldfish hepatocytes, hypotonic exposure leads to cell swelling, followed by a compensatory shrinkage termed RVD. It has been previously shown that ATP is accumulated in the extracellular medium of swollen cells in a non-linear fashion, and that extracellular ATP (ATPe) is an essential intermediate to trigger RVD. Thus, to understand how RVD proceeds in goldfish hepatocytes, we developed two mathematical models accounting for the experimental ATPe kinetics reported recently by Pafundo et al. in Am. J. Physiol. 294, R220–R233, 2008. Four different equations for ATPe fluxes were built to account for the release of ATP by lytic (JL) and nonlytic mechanisms (JNL), ATPe diffusion (JD), and ATPe consumption by ectonucleotidases (JV). Particular focus was given to JNL, defined as the product of a time function (JR) and a positive feedback mechanism whereby ATPe amplifies JNL. Several JR functions (Constant, Step, Impulse, Gaussian, and Lognormal) were studied. Models were tested without (model 1) or with (model 2) diffusion of ATPe. Mathematical analysis allowed us to get a general expression for each of the models. Subsequently, by using model dependent fit (simulations) as well as model analysis at infinite time, we observed that: – use of JD does not lead to improvements of the models. – Constant and Step time functions are only applicable when JR = 0 (and thus, JNL = 0), so that the only source of ATPe would be JL, a result incompatible with experimental data. – use of impulse, Gaussian, and lognormal JRs in the models led to reasonable good fits to experimental data, with the lognormal function in model 1 providing the best option. Finally, the predictive nature of model 1 loaded with a lognormal JR was tested by simulating different putative in vivo scenarios where JV; and JNL; were varied over ample ranges.Facultad de Ciencias ExactasInstituto de Física de Líquidos y Sistemas Biológico

Señas de identidad judías y cristianas en la cuentística medieval: algunos ejemplos hispánicos

In this article the authors analyze the role of the tale as a literary factor for the assertion of Jewish and Christian cultural identity in late Medieval Iberia. They offer, as an example, a corpus of short stories taken from a range of Jewish and Christian written sources containing elements relevant to the analysis.En este artículo los autores analizan la función del cuento como elemento literario de afirmación de la identidad cultural, judía o cristiana, en el mundo hispánico medieval. A modo de ilustración, se presenta un corpus de relatos tomados de obras medievales judías y en fuentes cristianas y que contienen elementos relevantes para el análisis

Kinetics of extracellular ATP in mastoparan 7-activated human erythrocytes

Background: The peptide mastoparan 7 (MST7) stimulated ATP release in human erythrocytes. We explored intraand extracellular processes governing the time-dependent accumulation of extracellular ATP (i.e., ATPe kinetics). Methods: Human erythrocytes were treated with MST7 in the presence or absence of two blockers of pannexin 1. ATPe concentration was monitored by luciferin–luciferase based real-time luminometry. Results: Exposure of human erythrocytes to MST7 led to an acute increase in [ATPe], followed by a slower increase phase. ATPe kinetics reflected a strong activation of ATP efflux and a low rate of ATPe hydrolysis by ectoATPase activity. Enhancement of [ATPe] by MST7 required adhesion of erythrocytes to poly-D-lysin-coated coverslips, and correlated with a 31% increase of cAMP and 10% cell swelling. However, when MST7 was dissolved in a hyperosmotic medium to block cell swelling, ATPe accumulation was inhibited by 49%. Erythrocytes pre-exposure to 10 μM of either carbenoxolone or probenecid, two blockers of pannexin 1, exhibited a partial reduction of ATP efflux. Erythrocytes from pannexin 1 knockout mice exhibited similar ATPe kinetics as those of wild type mice erythrocytes exposed to pannexin 1 blockers. Conclusions: MST7 induced release of ATP required either cell adhesion or strong activation of cAMP synthesis. Part of this release required cell swelling. Kinetic analysis and a data driven model suggested that ATP efflux is mediated by two ATP conduits displaying different kinetics, with one conduit being fully blocked by pannexin 1 blockers. General significance: Kinetic analysis of extracellular ATP accumulation from human erythrocytes and potential effects on microcirculation.Fil: Leal Denis, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Fisicoquímica Biológicas; ArgentinaFil: Incicco, Juan Jeremías. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Fisicoquímica Biológicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Biológica; ArgentinaFil: Espelt, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Fisicoquímica Biológicas; ArgentinaFil: Verstraeten, Sandra Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Fisicoquímica Biológicas; ArgentinaFil: Pignataro, Omar Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Lazarowski, Eduardo R.. University of North Carolina at Chapel Hill. Cystic Fibrosis/Pulmonary Research and Treatment Center; Estados UnidosFil: Schwarzbaum, Pablo Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Fisicoquímica Biológicas; Argentin