El mundo aún guarda muchas oportunidades

El ingeniero Juan Camilo atendió a una entrevista con el doctor Edison Valencia, miembro del Comité Editorial de la Revista Ingeniería Biomédica

Voltage-dependent gating of KCNH potassium channels lacking a covalent link between voltage-sensing and pore domains

Voltage-gated channels open paths for ion permeation upon changes in membrane potential, but how voltage changes are coupled to gating is not entirely understood. Two modules can be recognized in voltage-gated potassium channels, one responsible for voltage sensing (transmembrane segments S1 to S4), the other for permeation (S5 and S6). It is generally assumed that the conversion of a conformational change in the voltage sensor into channel gating occurs through the intracellular S4–S5 linker that provides physical continuity between the two regions. Using the pathophysiologically relevant KCNH family, we show that truncated proteins interrupted at, or lacking the S4–S5 linker produce voltage-gated channels in a heterologous model that recapitulate both the voltage-sensing and permeation properties of the complete protein. These observations indicate that voltage sensing by the S4 segment is transduced to the channel gate in the absence of physical continuity between the modules

The ecology of peace : preparing Colombia for new political and planetary climates

ABSTRACT: Colombia, one of the world’s most species-rich nations, is currently undergoing a profound social transition: the end of a decadeslong conflict with the Revolutionary Armed Forces of Colombia, known as FARC. The peace agreement process will likely transform the country’s physical and socioeconomic landscapes at a time when humans are altering Earth’s atmosphere and climate in unprecedented ways. We discuss ways in which these transformative events will act in combination to shape the ecological and environmental future of Colombia. We also highlight the risks of creating perverse development incentives in these critical times, along with the potential benefits – for the country and the world – if Colombia can navigate through the peace process in a way that protects its own environment and ecosystems

Kv7 Channels Can Function without Constitutive Calmodulin Tethering

M-channels are voltage-gated potassium channels composed of Kv7.2-7.5 subunits that serve as important regulators of neuronal excitability. Calmodulin binding is required for Kv7 channel function and mutations in Kv7.2 that disrupt calmodulin binding cause Benign Familial Neonatal Convulsions (BFNC), a dominantly inherited human epilepsy. On the basis that Kv7.2 mutants deficient in calmodulin binding are not functional, calmodulin has been defined as an auxiliary subunit of Kv7 channels. However, we have identified a presumably phosphomimetic mutation S511D that permits calmodulin-independent function. Thus, our data reveal that constitutive tethering of calmodulin is not required for Kv7 channel function

Estructura económica de Risaralda

Para conocer la historia de un país, también es indispensable conocer como han estado conformadas sus ciudades y cómo ha sido su recorrido a través del tiempo para tener una perspectiva mucho más amplia de su economía durante cada coyuntura. Es por esto, que la Historia Económica de Risaralda busca poner a disposición y resaltar una visión bastante amplia de su recorrido histórico y económico, partiendo desde los primeros habitantes y estructuras económicas del territorio, datadas desde tiempo precoloniales, y atravesando por las diferentes transformaciones que fueron afectando a Risaralda durante la colonia y en los años posteriores a esta, especialmente con acontecimientos como la colonización antioqueña, que dejó arraigada la actividad agrícola como la más importante de la economía departamental, aunque la misma con el pasar de los años en el siglo XX fue perdiendo importancia a causa del auge manufacturero, y especialmente del auge de la terciarización sustentada en la actividad comercial. Este fenómeno de terciarización económica será considerado de forma tanto histórica como actual, identificando cual es la situación económica vigente de Risaralda, y a partir de ello darse una idea de lo que le puede deparar al territorio en los próximos años, donde los objetivos de sostenibilidad y calidad de vida parecen ser las claves de toda iniciativa

Amor, empatía y conductas prosociales: una reflexión interdisciplinaria

This book presents, through reflection, the relevance, timeliness and necessity of love, empathy and prosocial behaviors within the framework of the professional and disciplinary work of the authors. The reader will be able to find here what these professionals, academics and intellectuals think and feel about it. Let the reader know that it was not a simple writing project, maybe because of the invitation to think about oneself, maybe because of the presence of the concept of "love" in the academy, or maybe, because we are not so accustomed to putting in the first person the reflection turned from what we relate to day by day. May this text be the excuse to continue to reflect on the role of love, empathy and prosocial behavior in a world that sometimes shows great desolation. May these unknotted reflections allow us to understand and resignify, learn and continue.PublishedEste libro expone, por la vía de la reflexión, la pertinencia, actualidad y necesidad del amor, la empatía y las conductas prosociales en el marco del quehacer profesional y disciplinar de los autores. El lector podrá encontrar aquí lo que esos profesionales, académicos e intelectuales piensan y sienten al respecto. Sepa el lector que no fue un proyecto de escritura sencillo, quizá por la invitación a pensar sobre sí, quizá por la presencia del concepto “amor” en la academia, o quizá, simplemente, porque no estamos tan acostumbrados a poner en primera persona la reflexión devenida de aquello con lo que día a día nos relacionamos. Que sea este texto la excusa para continuar reflexionando sobre el papel del amor, la empatía y las conductas prosociales en un mundo que a veces muestra gran desolación. Que estas reflexiones des-anudadas permitan comprender y resignificar, aprender y continuar

A pore residue of the KCNQ3 potassium M-channel subunit controls surface expression

KCNQ2 (Kv7.2) and KCNQ3 (Kv7.3) are the principal subunits underlying the potassium M-current, which exerts a strong control on neuronal excitability. KCNQ3 subunits coassemble with KCNQ2 to form functional heteromeric channels that are specifically transported to the axonal initial segment and nodes of Ranvier. In contrast, there is no evidence for functional homomeric KCNQ3 channels in neurons, and it appears that these are inefficiently trafficked to the plasma membrane. Among eukaryotic potassium channels, the KCNQ3 subunit is unusual because it has an alanine in place of a threonine at the pore inner vestibule, three residues upstream of the GYG signature sequence of the selectivity filter. This residue is critical for the potentiation of the current after heteromerization, but the mechanism is unknown. We report that the presence of this uncommon residue at position 315 has a strong impact on the stability of the homotetramers and on channel trafficking. Wild-type KCNQ3 expressed alone is retained within the endoplasmic reticulum, and this mechanism is overcome by the substitution of threonine for Ala315. KCNQ3 subunits require assembly with KCNQ2 to exit this compartment, whereas KCNQ3-A315T is no longer dependent on KCNQ2 to form channels that are efficiently trafficked to the plasma membrane. The presence of this alanine, therefore, plays an important role in regulating the subunit composition of functional M-channels expressed at the surface of neurons