History of Diabetes Insipidus

Under physiological conditions, fluid and electrolyte homoeostasis is maintained by the kidney adjusting urine volume and composition according to body needs. Diabetes Insipidus is a complex and heterogeneous clinical syndrome affecting water balance and characterized by constant diuresis, resulting in large volumes of dilute urine. With respect to the similarly named Diabetes Mellitus, a disease already known in ancient Egypt, Greece and Asia, Diabetes Insipidus has been described several thousand years later. In 1670s Thomas Willis, noted the difference in taste of urine from polyuric subjects compared with healthy individuals and started the differentiation of Diabetes Mellitus from the more rare entity of Diabetes Insipidus. In 1794, Johann Peter Frank described polyuric patients excreting nonsaccharine urine and introduced the term of Diabetes Insipidus. An hystorical milestone was the in 1913, when Farini successfully used posterior pituitary extracts to treat Diabetes Insipidus. Until 1920s the available evidence indicated Diabetes Insipidus as a disorder of the pituitary gland. In the early 1928, De Lange first observed that some patients with Diabetes Insipidus did not respond to posterior pituitary extracts and subsequently Forssman and Waring in 1945 established that the kidney had a critical role for these forms of Diabetes Insipidus resistant to this treatment. In 1947 Williams and Henry introduced the term Nephrogenic Diabetes Insipidus for the congenital syndrome characterized by polyuria and renal concentrating defect resistant to vasopressin. In 1955, du Vigneaud received the 1955 Nobel Prize in chemistry for the first synthesis of the hormone vasopressin representing a milestone for the treatment of Central Diabetes Insipidus

Curved domain walls dynamics driven by magnetic field and electric current in hard ferromagnets

Abstract The propagation of curved domain walls in hard ferromagnetic materials is studied by applying a reductive perturbation method to the generalized Landau–Lifshitz–Gilbert equation. The extended model herein considered explicitly takes into account the effects of a spin-polarized current as well as those arising from a nonlinear dissipation. Under the assumption of steady regime of propagation, the domain wall velocity is derived as a function of the domain wall curvature, the nonlinear damping coefficient, the magnetic field and the electric current. Threshold and Walker-like breakdown conditions for the external sources are also determined. The analytical results are evaluated numerically for different domain wall surfaces (planes, cylinders and spheres) and their physical implications are discussed

Oscillatory periodic pattern dynamics in hyperbolic reaction-advection-diffusion models

In this work we consider a quite general class of two-species hyperbolic reaction-advection-diffusion system with the main aim of elucidating the role played by inertial effects in the dynamics of oscillatory periodic patterns. To this aim, first, we use linear stability analysis techniques to deduce the conditions under which wave (or oscillatory Turing) instability takes place. Then, we apply multiple-scale weakly nonlinear analysis to determine the equation which rules the spatiotemporal evolution of pattern amplitude close to criticality. This investigation leads to a cubic complex Ginzburg-Landau (CCGL) equation which, owing to the functional dependence of the coefficients here involved on the inertial times, reveals some intriguing consequences. To show in detail the richness of such a scenario, we present, as an illustrative example, the pattern dynamics occurring in the hyperbolic generalization of the extended Klausmeier model. This is a simple two-species model used to describe the migration of vegetation stripes along the hillslope of semiarid environments. By means of a thorough comparison between analytical predictions and numerical simulations, we show that inertia, apart from enlarging the region of the parameter plane where wave instability occurs, may also modulate the key features of the coherent structures, solution of the CCGL equation. In particular, it is proven that inertial effects play a role, not only during transient regime from the spatially-homogeneous steady state toward the patterned state, but also in altering the amplitude, the wavelength, the angular frequency, and even the stability of the phase-winding solutions

Aciertos y desafíos de una escuela eficaz. Un estudio de caso microsociológico e interaccional

Este artículo indaga cómo la gestión institucional, el involucramiento docente y familiar se amalgaman para el logro escolar sostenido. Se desarrolló en una escuela primaria ubicada en una comunidad marginada en Las Choapas, Veracruz. Los estudiantes obtuvieron puntajes superiores a la media nacional en las pruebas ENLACE 2012, PLANEA 2015 y 2016. Mediante un estudio de caso cualitativo se recabó información con docentes, directivos y familias. Luego del análisis de las interacciones entre los actores educativos, encontramos que la gestión institucional está basada en un liderazgo distribuido, consolidado, con eficiencia técnico-pedagógica; los docentes son experimentados, autónomos, creativos, con arraigo en la comunidad. Las familias se involucran activamente en la escuela, la que perciben como un espacio de interés público y de responsabilidad común. Concluimos que es un centro educativo eficaz y resiliente, los actores asumen con compromiso la tarea de ofrecer una educación de calidad, pese a sus condiciones adversas

EGF stimulates IClswell by a redistribution of proteins involved in cell volume regulation.

Background: ICln is a multifunctional protein involved in the generation of chloride currents activated during regulatory volume decrease (RVD) after cell swelling (IClswell). Growth factor receptors play a key role in different cellular processes and epidermal growth factor (EGF) regulates swelling-activated chloride permeability. Aim: We set out to investigate if the EGF-induced upregulation of IClswell could be explained by a rearrangement of ICln subcellular distribution and interaction with its molecular partners. Methods: NIH-3T3 fibroblasts were serum-deprived for 24 hours and stimulated with EGF (40 ng/ml) for 30 minutes. IClswell activation, ICln distribution and interaction with its molecular partner HSPC038 were assessed by whole cell patch clamp and fluorescence resonance energy transfer (FRET). Results: EGF treatment significantly enhanced the direct molecular interaction between ICln and HSPC038 and also resulted in an increase of ICln and HSPC038 association with the plasma membrane. Importantly, these events are associated with a significant increase of IClswell. Conclusions: The present data indicate that EGF might exert its role in the modulation of volume-sensitive chloride currents in part through activation and translocation of ICln and HSPC038 to the plasma membrane

Differential modulation of intracellular Ca2+ responses associated with calcium-sensing receptor activation in renal collecting duct cells.

In this work, we studied G protein-coupled Extracellular Calcium Sensing Receptor (CaR) signaling in mouse cortical collecting duct cells (MCD4) expressing endogenous CaR. Intracellular [Ca2+] measurements performed with real time video imaging revealed that CaR stimulation with 5mM Ca2+, 300µM Gd3+ and with 10µM of specific allosteric modulator NPS-R 568, all resulted in an increase in [Ca2+]i although displaying different features. Specifically, Ca2+ as well as stimulation with NPS-R 568 induced a rapid peak of [Ca2+]i while stimulation with Gd3+ induced transient intracellular Ca2+ oscillations. PLC inhibition completely abolished any [Ca2+]i increase after stimulation with CaR agonists. Inhibition of Rho or Rho kinase (ROK) abolished [Ca2+]i oscillations induced by Gd3+, while the peak induced by high Ca2+ was similar to control. Conversely, emptying the intracellular calcium stores abolished the response to Gd3+. On the other hand, the inhibition of calcium influx did not alter calcium changes. We conclude that in our cell model, CaR stimulation with distinct agonists activates two distinct transduction pathways, both PLC-dependent. The transient cytosolic Ca2+ oscillations produced by Gd3+ are modulated by Rho-Rho kinase signaling, whereas the rapid peak of intracellular Ca2+ in response to 5mM [Ca2+]o is mainly due to PLC/IP3 pathway activation

Integrin signaling modulates AQP2 trafficking via Arg-Gly-Asp (RGD) motif.

Aquaporin-2 (AQP2) increases the water permeability of renal collecting ducts in response to vasopressin. Vasopressin stimulation is accompanied by a profound remodeling of actin cytoskeleton whose dynamics are regulated by crosstalk between intracellular and extracellular signals. Here, we report that AQP2 contains a conserved RGD domain in its external C-loop. Co-immunoprecipitation experiments demonstrated that AQP2 binds integrin β1 in renal tissue and in MCD4 cells. To investigate the role of this interaction on AQP2 trafficking, cells were exposed to synthetic RGD-containing peptides, GRGDNP or GRGDSP, able to bind certain integrins. Incubation with these peptides increased the membrane expression of AQP2 in the absence of hormonal stimulation as assessed by confocal analysis and cell surface biotinylation. To identify the signals underlying the effects of peptides on AQP2 trafficking, some possible intracellular messengers were evaluated. Exposure of MCD4 cells to GRGDNP increased intracellular cAMP as assessed by FRET studies while GRGDSP increased intracellular calcium concentration. Taken together, these data propose integrins as new players controlling the cellular localization of AQP2, via two distinct signal transduction pathways dependent on cAMP and calcium respectively

Exclusión social en Ecuador. Buen Vivir y modernización capitalista

Este artículo examina la adopción del enfoque de inclusión social que se desarrolla en la Constitución, el Plan de Desarrollo Nacional, y en la operación ministerial de la política social en Ecuador bajo la presidencia de Rafael Correa. A nivel normativo se constata un enfoque de inclusión social enmarcado en el paradigma del Buen Vivir, que implica una transformación del modelo de desarrollo seguido y, con éste, del sentido y alcance de las políticas sociales. Esto último supone el tránsito de un enfoque de corte asistencialista, centrado en la pobreza, a otro de alcance universal. Se analizan los planteamientos normativos de esta propuesta, los avances logrados y las dificultades en su implementación, en el contexto de un modelo de desarrollo capitalista oligopólico extractivista.This paper considers the adoption of the perspective of social inclusion developed in the Constitution, in the National Development Plan, and in the implementation of social policy at institutional level in Ecuador under President Correa’s administration. At normative level we can observe that a social inclusion approach has been developed, framed under the Buen Vivir paradigm which entails transforming the followed development model together with the meaning and the scope of social policies. This implies shifting from a social policy focused on poverty to a universal approach. The normative assumptions are analyzed, as well as the achievements and the obstacles at the implementation level, considering the extractive capitalist model.Este artigo analisa a adoção da abordagem de inclusão social que se desenvolve na Constituição, o Plano Nacional de Desenvolvimento e na operação ministerial da política social no Equador sob a presidência de Rafael Correa. No nível normativo constata-se um enfoque de inclusão social enquadrado no paradigma do Bem Viver, o que implica uma transformação do modelo de desenvolvimento seguido e, junto com este, do significado e alcance das políticas sociais. Isto último envolve a passagem de uma abordagem tipo assistencialistas, com foco na pobreza, para outra de âmbito universal. Finalmente, analisam-se as abordagens regulatórias desta proposta, os avanços obtidos e as dificuldades na sua implementação, no contexto de um modelo de desenvolvimento capitalista oligopolista e extrativista