From stem and progenitor cells to neurons in the developing neocortex: Key differences among hominids

Comparing the biology of humans to that of other primates, and notably other hominids, is a useful path to learn more about what makes us human. Some of the most interesting differences among hominids are closely related to brain development and function, for example behaviour and cognition. This makes it particularly interesting to compare the hominid neural cells of the neocortex, a part of the brain that plays central roles in those processes. However, well-preserved tissue from great apes is usually extremely difficult to obtain. A variety of new alternative tools, for example brain organoids, are now beginning to make it possible to search for such differences and analyse their potential biological and biomedical meaning. Here, we present an overview of recent findings from comparisons of the neural stem and progenitor cells (NSPCs) and neurons of hominids. In addition to differences in proliferation and differentiation of NSPCs, and maturation of neurons, we highlight that the regulation of the timing of these processes is emerging as a general foundational difference in the development of the neocortex of hominids

Quantitative Analysis of the Structural Dynamics of Mitotic Chromosomes in Live Mammalian Cells

Chromatin, organized into individual chromosomes, is the physiological carrier of the genetic and epigenetic information in eukaryotes. In the nucleus of an intact cell, the structure of chromatin is dynamic and essential for genomic activities. The most dramatic changes in chromatin structure occur in mitosis, when compact metaphase chromosomes are formed, organized and partitioned equally to two daughter cells. How this vital reorganization of chromatin is accomplished remains poorly understood in vivo. To address this, in the first part of my thesis I developed quantitative assays to determine the kinetics of mitotic chromosome compaction, using multidimensional confocal microscopy of live cells stably expressing fluorescent histone 2b. Condensation was measured at three different scales: Large-scale (~800 nm), where the chromatin volume was measured by high resolution 4D imaging; medium scale (~200 nm) by statistical analysis of pixel intensities; and molecular scale (~10 nm) by a FRET reporter of histone tail environment. These measurements show that (i) mitotic compaction may start at least 20 min before prometaphase; (ii) it correlates with changes in histone tail conformation; (iii) chromatin density is not highest in metaphase but in late anaphase chromosomes. In the second part, I focused on the novel finding of highest compaction in anaphase. Single chromosome measurements revealed that chromatids compact in anaphase by a mechanism of lengthwise shortening that starts only after segregation of the sister chromatids is complete. This axial shortening was not affected in condensin-depleted cells, and was independent of the poleward pulling motion on kinetochores, but it nevertheless depended on dynamic microtubules. Perturbation of this shortening caused a severe phenotype of multi-lobulated daughter nuclei, strongly suggesting a function in post-mitotic nuclear assembly and architecture. In addition, if anaphase compaction was perturbed in condensin-depleted cells, segregation defects increased 3-fold, suggesting a second role for anaphase compaction as a rescue mechanism for segregation defects. In the third part, the quantitative compaction assays were used to probe the role of PNUTS, a major protein phosphatase 1 nuclear-targeting subunit, in the regulation of chromatin structure. In live cells depleted of PNUTS by RNAi, compaction was slowed at least 3-fold. Our collaborators in the group of Philippe Collas at the University of Oslo had shown that PNUTS accelerates chromatin decompaction in vitro. PNUTS is thus involved in mitotic chromatin structure in vivo and in vitro, and my findings make it an interesting target for future research to understand the molecular mechanism of chromosome compaction

A study on EEG power and connectivity in a virtual reality bimanual rehabilitation training system

The study of neural processes that describe bimanual activity in areas such as neurology and rehabilitation are of high interest, in particular for rehabilitation after brain injury. However, brain processes during bimanual motor rehabilitation are not fully understood during stroke rehabilitation. Hence, it is not clear how to exploit them and their possible advantages in an EEG driven Virtual Reality (VR) training. In this work, VR and EEG were combined to study the neural processes in motor areas during bimanual activity in a serious game, involving two kind of movements: Left to Right (L2R) movement (Right handle forward and Left handle backward movements) and Right to Left (R2L) movement (Right handle backward and Left handle forward movements). 10 right handed healthy people (7 Males, 3 Females, 29.9 ± 6.21 years old) participated in this study. As it was expected, differences between rest and bimanual activity conditions (L2R and R2L) were found, surprisingly, on lowest frequency bands, Delta and Theta. More relevant results were found on Delta band at the right Hemisphere and inter-hemispherical relations, specifically for intra-hemispherical connectivity for CPSD relations with p=0.005 (L2R) and p=0.02 (R2L), and power quantified with PSD with p=0.023 (L2R) and p=0.03 (R2L), while inter-hemispherical connectivity got lower values on resting compared to L2R movement with a p=0.015. Besides, comparisons between resting and movement in Theta band showed significant results for inter-hemispherical connectivity (p=0.03, L2R vs Rest, and R2L vs Rest) and differences in power for Left Hemisphere (p=0.05). Finally, non-significant differences were found in motor cortex between the two kind of bimanual activities tested on this work. These results create an opening scenario to test for mirror effect of bimanual activities from one hemisphere to another on populations with hemi paretic conditions, aiming to apply it in a near future as therapy for Stroke Survivors.info:eu-repo/semantics/publishedVersio

Changes in EMG activity during clenching in chronic pain patients with unilateral temporomandibular disorders

[Abstract] The study assessed the differences in electromyographic (EMG) activity recorded during clenching in women with chronic unilateral temporomandibular disorders (TMDs) as compared to control subjects. Seventy-five full dentate, normo-occlusion, right-handed, similarly aged female subjects were recruited. Twenty five subjects presented with right side TMD, 25 presented with left side TMD and 25 pain-free control subjects participated. Using integrated surface EMG over a 1 s contraction, the anterior temporalis and masseter muscles were evaluated bilaterally while subjects performed maximum voluntary clenching. Lower EMG activation was observed in patients with TMD as compared to control subjects (temporalis: 195.74 ± 18.57 vs. 275.74 ± 22.11, P = 0.011; masseters: 151.09 ± 17.37 vs. 283.29 ± 31.87, P < 0.001). An asymmetry index (SAI) was calculated to determine ratios of right to left sided activation. Patients with right-sided TMD demonstrated preferential use of their left-sided muscles (SAI −5.35 ± 4.02) whereas patients with left-sided TMD demonstrated preferential use of their right-sided muscles (SAI 6.95 ± 2.82), (P = 0.016). This unilateral reduction in temporalis and masseter activity could be considered as a specific protective functional adaptation of the neuromuscular system due to nociceptive input. The asymmetry index (SAI) may be a useful measure in discriminating patients with right vs. left-sided TMD.Galicia. Consellería de Cultura, Educación e Ordenación Universitaria; Grant 9/7/1996/DOG/22/7/199

Caso Garittea, del campo al campus: creación del diseño de la identidad visual de una organización a través del trabajo colaborativo entre comunidades campesinas y la academia

[EN] This paper presents the joint work experience between academics, ONGs, and farmer´s associations, about the development of capabilities for the marketing of coffee products, in the framework of colaborative and participative design, that allows the progress in the construction of solidary economic chanels and fair trade. Garittea is a social entrepreneurship that lowers commercial intermediation, defends the income of small coffee producers, and creates empowerment processes in the rural comunities; Garittea is a brand created for strengthtening rural-urban relations, sustainable development, the promotion of interdisciplinary and colaborative work, esential elements in the creation of business identity and the design of an organization visual comunication. Villafañe (2008) states that corporative identity is the “being” of a company, its essence, a concept that is taken as a reference and highlights the importance of collective work in the creation of identity of organizations. This study reveals the several ways of participation and involvement of different actors and areas of knowledge in the processes of design and management of an organization, that creates positioning and visibility of the character of a productive community. The identity of Garittea departs from an integrated vision, articulated with triple helix perspective (Etzkowitz et al. 2000) where companies, universities, and other organizations are willing to work jointly with a colaborative commitment. The actors in the process are defined by a triad, the firm (Garittea shareholders): the Association of Small Coffee Growers of La Marina, the Association of Colombian Organic Coffee Growers and the Instituto Mayor Campesino, who have contributed with their knowhow and experience in the processes of creating new products; a team of I+D + i (teachers and administrators), who have incorporated their methodologies and tools through interdisciplinary knowledge in areas such as marketing, engineering, economics, psychology, and design, using among other resources, systemic models of formulation by objectives to support the creative process and the design management; and, finally, the designers (the students), who have worked on creating Garittea´s identity through an integrated team, resulting in the creation of corporate identity and visual identity of Garittea.[ES] Se presenta la experiencia de articulación entre academia, ONG y asociaciones campesinas, alrededor del desarrollo de capacidades para la comercialización de productos de café, en el marco del diseño colaborativo, que permite avanzar en la construcción de canales de economía solidaria y comercio justo. Garittea es una empresa social que disminuye la intermediación comercial, defiende los ingresos de los pequeños caficultores y genera procesos de empoderamiento en las comunidades campesinas; es una marca creada para el fortalecimiento de las relaciones campo-ciudad, el desarrollo sostenible, el impulso del trabajo interdisciplinario y colaborativo, elementos esenciales en la creación de la identidad y el diseño de comunicación visual de una organización. Villafañe (2008) afirma que la identidad corporativa es el “ser” de la empresa, su esencia, concepto que se toma como referencia y pone de manifiesto la importancia del trabajo colectivo en la creación de la identidad en las organizaciones. Este estudio deja ver los modos de participación e intervención de los distintos actores y áreas del conocimiento en los procesos de diseño y gestión de una organización, generando el posicionamiento y la visibilización del carácter de una comunidad productiva. La identidad de Garittea parte de una visión integradora articulada con perspectiva de la triple hélice (Etzkowitz et al. 2000) donde empresas, universidades y otras organizaciones se encuentran para trabajar con un compromiso colaborativo.Los actores del proceso se definen a través de una triada, compuesta por la empresa, (socios de Garittea): la Asociación de Pequeños Caficultores de La Marina, la Asociación de Caficultores Orgánicos de Colombia y el Instituto Mayor Campesino, quienes han aportado su know–how y la experiencia de sus procesos de creación de nuevos productos; un equipo de I+D+i (profesores y gestores), quienes han incorporado sus metodologías y herramientas a través de la interdisciplinariedad en saberes como el mercadeo, la ingeniería, la economía, la psicología y el diseño, aplicando entre otros recursos, modelos sistémicos de formulación por objetivos para apoyar los procesos creativos y la gestión del diseño; los diseñadores (estudiantes), quienes han trabajado en la creación de la identidad de Garittea a través de un equipo integral, dando como resultado la creación de la identidad corporativa e identidad visual de Garittea.Rosales, E.; Mora, C.; Mora, F.; Morales, R.; Bermúdez, D. (2016). Caso Garittea, del campo al campus: creación del diseño de la identidad visual de una organización a través del trabajo colaborativo entre comunidades campesinas y la academia. En Systems&design:beyond processes and thinking. Editorial Universitat Politècnica de València. 347-360. https://doi.org/10.4995/IFDP.2015.3264OCS34736

Expectativas de futuro de adolescentes procedentes de distintos contextos sociales

This paper analyzes adolescents’ future expectations (FE) and their relationship with personal variables (age, sex, self-esteem, and life satisfaction) and contextual variables (perceived social support and level of risk). The sample includes 748 adolescents, aged 9-16 (M = 11.93, SD = 1.42), coming from contexts with different levels of social risk. The results show that FE decrease as age increases, with few differences found based on sex. More positive self-perceptions and perceived social support are associated with better FE. Concerning the level of risk, more vulnerable contexts have a higher negative effect on FE. The regression analysis reveals the predictive capacity of the studied variables. The structural equation model confirms the positive causal effect of psychological adjustment and perceived social support, as well as the negative influence of contexts with greater social disadvantages on adolescent FE. The results suggest the need to establish preventive programs aimed at promoting personal resources of children, especially those who come from vulnerable contexts.Este trabajo analiza las expectativas futuras durante la adolescencia y su relación con variables personales (edad, sexo, autoestima y satisfacción vital) y contextuales (apoyo social percibido y nivel de riesgo). La muestra está formada por 748 adolescentes, con edades comprendidas entre los 9 y 16 años (M = 11.93, SD = 1.42) procedentes de contextos con distinto nivel de riesgo social. Los resultados muestran que las expectativas futuras disminuyen a medida que aumenta la edad, con pocas diferencias encontradas en función del sexo. Autopercepciones y sentimientos de apoyo social más positivos se asocian a mejores expectativas futuras. En relación al nivel de riesgo, contextos más vulnerables tienen un efecto negativo en las expectativas futuras. Los análisis de regresión muestran la capacidad predictiva de las variables estudiadas. Finalmente, el modelo de ecuaciones estructurales confirma el efecto causal positivo del ajuste psicológico y del apoyo social percibido, así como la influencia negativa de los contextos con mayores desventajas sociales, sobre las expectativas de futuro. Los resultados encontrados proponen la necesidad de instaurar programas preventivos orientados a fomentar los recursos personales de los niños, especialmente en aquellos que pertenecen a contextos vulnerables

Rediseño del Sistema de Gestión de la Calidad a través de metodologías de mejora de procesos para incrementar la productividad en una empresa metalmecánica de Bogotá.

En el presente trabajo de grado se muestra el proceso de rediseño de un sistema de gestión de calidad para una empresa del sector metal mecánico, definiendo el estado de la empresa tanto en sus procesos internos como su posicionamiento en el mercado respecto a sus principales competidores, pasando por el análisis estratégico basado en herramientas de gestión (Matrices MEFE, MEFI, MIME, PESTEL, PORTER, Perfil Competitivo), así como el referente a cumplimiento de normativa legal vigenteEspecialista en Gerencia Integral de la CalidadEspecializació

Temporomandibular disorders: the habitual chewing side syndrome

Background:Temporomandibular disorders are the most common cause of chronic orofacial pain, but, except where theyoccur subsequent to trauma, their cause remains unknown. This cross-sectional study assessed chewing function (habitualchewing side) and the differences of the chewing side and condylar path and lateral anterior guidance angles in participantswith chronic unilateral temporomandibular disorder. This is the preliminary report of a randomized trial that aimed to testthe effect of a new occlusal adjustment therapy.Methods:The masticatory function of 21 randomly selected completely dentate participants with chronic temporoman-dibular disorders (all but one with unilateral symptoms) was assessed by observing them eat almonds, inspecting the lateralhorizontal movement of the jaw, with kinesiography, and by means of interview. The condylar path in the sagittal plane andthe lateral anterior guidance angles with respect to the Frankfort horizontal plane in the frontal plane were measured onboth sides in each individual.Results:Sixteen of 20 participants with unilateral symptoms chewed on the affected side; the concordance (Fisher’s exacttest, P = .003) and the concordance-symmetry level (Kappa coefficientk= 0.689; 95% confidence interval [CI], 0.38 to 0.99;P = .002) were significant. The mean condylar path angle was steeper (53.47(10.88) degrees versus 46.16(7.25) degrees;P = .001), and the mean lateral anterior guidance angle was flatter (41.63(13.35) degrees versus 48.32(9.53) degrees P = .036)on the symptomatic side.Discussion:The results of this study support the use of a new term based on etiology, ‘‘habitual chewing side syndrome’’,instead of the nonspecific symptom-based ‘‘temporomandibular joint disorders’’; this denomination is characterized inadults by a steeper condylar path, flatter lateral anterior guidance, and habitual chewing on the symptomatic sideThis study was financed with a grant PI11/02507 from the Institute of Health Carlos III of the Ministry of Science and Innovation of the Government of Spain. It was completed with the equipment granted by the General Directorate of Universities and Research; Department of Education and University. Xunta de Galicia. Official Journal No. 143 Galicia, July 22, 1996. And the Department of Innovation, Industry and Commerce. Xunta de Galicia, April 30, 2004S