Desarrollo cognitivo, del lenguaje oral y el juego en la infancia

En este trabajo analizamos investigaciones acerca del desarrollo cognitivo y del lenguaje de niños mexicanos. Nos interesa en particular dar cuenta de la investigación con enfoque sociocultural del desarrollo cognitivo y del lenguaje que enfatiza el origen social de los procesos psicológicos y que incluye el desarrollo emocional como parte del campo del desarrollo cognoscitivo.ITESO A.C

A crop wild relative conservation strategy for Mexico

There is an extensive diversity of crops and their wild relatives in Mexico, which are distributed throughout the country. Crop wild relatives (CWR) play a special role for present and future food security strategies: they represent a potential source of variation for the domesticated species, contributing to the genetic improvement of these crops. However, the effects of climate change, among other threats, are reducing significantly this biodiversity. The purpose of this study was to analyse the diversity of wild relatives of the most important crops in Mexico as a basis for the development and implementation of a national conservation strategy for these genetic resources. The methods involved the identification of priorities and creation of a national CWR inventory, in situ and ex situ gap analyses at taxon and ecogeographic levels, the evaluation of the impacts of climate change, threat assessment and predictive characterisation. Applying these methods, 310 CWR taxa were identified as priorities and recommendations for immediate in situ and ex situ conservation actions were made to ensure their representativeness under current and future climatic conditions. All these components contribute to the systematic active long-term conservation of priority CWR diversity in the country and enhance their sustainable utilisation thus helping mitigate the threats to Mexican agrobiodiversity and global food security

Influence of environmental variables on fear of crime: Comparing self-report data with physiological measures in an experimental design

Objectives Self-reports and questionnaires have been the preferred research methods in the criminological field of Bfear of crime^ (FOC) since its rise in the 1960s. Our study had two main goals: (1) to measure the physiological indicators of fear in real time and (2) to compare these data with those obtained through self-reports, designed also to measure the emotion of fear. Methods An experimental study was conducted over the course of a week during late February 2016 in Aarhus (Denmark), in which the focus was on traditional environmental variables in the field of FOC (i.e., poor lighting conditions). Results Our results support the ideas that: (1) the absence of good luminosity in an open public space in an urban setting elicits physiological reactions of arousal that can be taken as indicators of experiences of fear and (2) heart rate appears to capture aspects of the emotion of fear that are not reflected in data obtained through self-report questionnaires Conclusions This study, introducing a pioneering approach to the study of FOC, presents great potentials in complementing traditional methods in the crime sciences. The many challenges we faced are significant and reported with the hope that subsequent literature will build upon. We propose that traditional methods and new measurements could be combined to advance research in the field by allowing researchers to more unambiguously constrain the interpretation of their data. This becomes particularly relevant in a field like FOC, which has long suffered from irreconcilable results stemming from different investigation

Why should we keep the cerebellum in mind when thinking about addiction?

Increasing evidence has involved the cerebellum in functions beyond the sphere of motor control. In the present article, we review evidence that involves the cerebellum in addictive behaviour. We aimed on molecular and cellular targets in the cerebellum where addictive drugs can act and induce mechanisms of neuroplasticity that may contribute to the development of an addictive pattern of behaviour. Also, we analyzed the behavioural consequences of repetitive drug administration that result from activitydependent changes in the efficacy of cerebellar synapses. Revised research involves the cerebellum in drug-induced long-term memory, druginduced sensitization and the perseverative behavioural phenotype. Results agree to relevant participation of the cerebellum in the functional systems underlying drug addiction. The molecular and cellular actions of addictive drugs in the cerebellum involve long-term adaptative changes in receptors, neurotransmitters and intracellular signalling transduction pathways that may lead to the re-organization of cerebellar microzones and in turn to functional networks where the cerebellum is an important nodal structure. We propose that drug induced activity-dependent synaptic changes in the cerebellum are crucial to the transition from a pattern of recreational drug taking to the compulsive behavioural phenotype. Functional and structural modifications produced by drugs in the cerebellum may enhance the susceptibility of fronto-cerebellar circuitry to be changed by repeated drug exposure. As a part of this functional reorganization, drug-induced cerebellar hyper-responsiveness appears to be central to reducing the influence of executive control of the prefrontal cortex on behaviour and aiding the transition to an automatic mode of contro

Interleukin-25 induces resistance against intestinal trematodes

Echinostoma caproni is an intestinal trematode that has been extensively used as an experimental model to investigate the factors determining the resistance to intestinal helminths or the development of chronic infections. ICR mice are permissive hosts for E. caproni in which chronic infections are developed, concomitantly with local Th1 responses, elevated levels of local IFN-γ, inflammation and antibody responses. However, mice develop partial resistance to homologous challenge infections after cure of a primary infection, which converts this subject into an adequate model for the study of the mechanisms generating resistance against intestinal helminths. The purpose of the present study was to compare the immune response induced in primary and secondary infections to elucidate the factors determining the different outcome of the infection in each type of infection. The results obtained indicate that susceptibility is determined by the lack of IL-25 expression in response to primary infection. In contrast, infection in an environment with elevated levels of IL-25, as occurs in challenge infection, results in a Th2 phenotype impairing parasite survival. This was confirmed by treatment of naïve mice with exogenous IL-25 and subsequent infection. Changes induced in goblet cell populations and mucin glycosylation could be implicated in resistance to infection

El cerebelo en el Autismo

Autism is considered as a neurodevelopmental disorder which affects boys more than girls, in a proportion 4:1 respectively. Autism presents neuroanatomical abnormalities located in the frontal cortex, the amygdala and the cerebellum. Autistic cerebellar postmortem studies have revealed a reduced number of Purkinje cells as well as a reduced Purkinje cell size when compared with non-autistic subjects. These anatomical alterations compromise the role of the cerebellum in cognitive, motor, emotional, learning and memory neural processes resulting in a different interpretation of the world, and therefore a different way to respond and behave. There are both biological and environmental insults causing the behavioral and neuroanatomical autistic phenotype. Valproic acid, an antiepileptic drug, has been related to some autistic cases after mothers were under medication with this drug during the first trimester of gestation and given birth autistic children. Therefore, in this brief review we analyzed the most recent advances of autism research in humans, with a primary focus on the use of valproic acid as a teratogen that mimics in rats some of the neuroanatomical alterations seen in autistic humans. In addition to the peculiar cerebellar pathology, all of this to shed light on a better understating of this disorder.El autismo es un trastorno generalizado del desarrollo que afecta más a varones que mujeres, con una proporción de 4 a 1, respectivamente. Dentro de sus características neuropatológicas más sobresalientes se encuentran la alteración anatómica de diversas estructuras del sistema nervioso central como la corteza frontal, la amígdala y el cerebelo. Estudios post mórtem en cerebelos de sujetos autistas han mostrado una notable disminución en el número de neuronas de Purkinje así como en su tamaño, comparado con las de sujetos sanos. Estas alteraciones anatómicas comprometen la participación del cerebelo en los procesos neurales como la cognición, actividad motora, la emoción, el aprendizaje y la memoria, dando como resultado una interpretación diferente del mundo que impacta sobre la respuesta y el comportamiento de los sujetos autistas. Actualmente se desconoce la causa de estas alteraciones anatómicas y aunque se avanza rápido en la ciencia se tiene la limitante de los sujetos experimentales, que en este caso son humanos. Por lo tanto, en esta revisión analizamos los hallazgos más relevantes de la patología cerebelar en el autismo, así como el uso del ácido valproico en ratas como teratógeno para simular alteraciones cerebelares como las observadas en autistas, contribuyendo a un mejor entendimiento de su neuropatología

Prenatal exposure to sodium valproate alters androgen receptor expression in the developing cerebellum in a region and age specific manner in male and female rats

Valproic acid (VPA) is an anti-epileptic drug with teratogenicity activity that has been related to autism. In rodents, exposure to VPA in utero leads to brain abnormalities similar than those reported in the autistic brain. Particularly, VPA reduces the number of Purkinje neurons in the rat cerebellum parallel to cerebellar abnormalities found in autism. Thus, we injected pregnant females on embryonic day 12 either with VPA (600 mg/kg, i.p.) or 0.9% saline solution and obtained the cerebellum from their offspring at different postnatal time points. Testosterone has been linked to autism and plays an important role during brain development. Therefore, we identified and analyzed the androgen receptor (AR) by immunohistochemistry and densitometry, respectively. We found VPA decreases AR density in the superficial Purkinje layer only in cerebellar lobule 8 at PN7, but increased it at PN14 compared to control in males. In females, VPA decreased AR density in the superficial Purkinje layer in cerebellar lobule 6 at PN14, but increased it in lobule 9 at the same time point. No differences were found in the deep Purkinje layer of any cerebellar lobule in terms of AR density neither in males nor females. We additionally found a particular AR density decreasing in both superficial and deep regions across development in the majority of cerebellar lobules in males, but in all cerebellar lobules in females. Thus, our results indicate that VPA disrupts the AR ontogeny in the developing cerebellum in an age and region specific manner in male and female rats. Future epigenetic studies including the evaluation of histone deacetylases (HDAC’s) might shed light these results as HDAC’s are expressed by Purkinje neurons, interact with the AR and are VPA targets. This work contributes to the understanding of the cerebellar development and it might help to understand the role of the cerebellum in neurodevelopmental disorders such as autism.This research was supported by CONACYT (Consejo Nacional de Ciencia y Tecnologia of Mexico Grant 106531 to Maria Elena Hernandez (MEH) and CONACYT Doctorate scholarship 205779 to Miguel Perez Pouchoulen (MPP). Authors thank M.S. Dulce Mariely Alvarez-Croda for her valuable comments to the manuscript

Photosynthetic biogas upgrading to bio-methane: Boosting nutrient recovery via biomass productivity control

Producción CientíficaA pilot high rate algal pond (HRAP) interconnected to an external CO2–H2S absorption column via settled broth recirculation was used to simultaneously treat a synthetic digestate and to upgrade biogas to a bio-methane with sufficient quality to be injected into natural gas grids. An innovative HRAP operational strategy with biomass recirculation based on the control of algal-bacterial biomass productivity (2.2, 4.4 and 7.5 g m− 2 d− 1) via settled biomass wastage was evaluated in order to enhance nutrient recovery from digestate at a constant hydraulic retention time. The influence of the recycling liquid to biogas (L/G) ratio on the quality of the upgraded biogas was assessed. The bio-methane composition under a L/G ratio of 1 (0.4 ± 0.1% CO2, 0.03 ± 0.04% O2, 2.4 ± 0.2% N2 and 97.2 ± 0.2% CH4) complied with the technical specifications of most European bio-methane legislations regardless of the biomass productivity established. The HRAP operational strategy applied allowed increasing the N and P recovery from 19 and 22% to 83 and 100%, respectively, when the biomass productivity was increased from 2.2 to 7.5 g m− 2 d− 1. Finally, the dynamics of microalgae and bacteria population structure were characterized by morphological identification and Denaturing Gradient Gel Electrophoresis analysis.Ministerio de Economía, Industria y Competitividad (Proyect CTM2015-70442-R

A study of the prostate, androgens and sexual activity of male rats

BACKGROUND: The prostate is a sexual gland that produces important substances for the potency of sperm to fertilize eggs within the female reproductive tract, and is under complex endocrine control. Taking advantage of the peculiar behavioral pattern of copulating male rats, we developed experimental paradigms to determine the influence of sexual behavior on the level of serum testosterone, prostate androgen receptors, and mRNA for androgen receptors in male rats displaying up to four consecutive ejaculations. METHODS: The effect of four consecutive ejaculations was investigated by determining levels of (i) testosterone in serum by solid phase RIA, (ii) androgen receptors at the ventral prostate with Western Blots, and (iii) androgen receptors-mRNA with RT-PCR. Data were analyzed with a one-way ANOVA followed by a post hoc application of Dunnett's test if required. RESULTS: The constant execution of sexual behavior did not produce any change in the weight of the ventral prostate. Serum testosterone increased after the second ejaculation, and remained elevated even after four ejaculations. The androgen receptor at the ventral prostate was higher after the first to third ejaculations, but returned suddenly to baseline levels after the fourth ejaculation. The level of mRNA increased after the first ejaculation, continued to increase after the second, and reached the highest peak after the third ejaculation; however, it returned suddenly to baseline levels after the fourth ejaculation. CONCLUSION: Four consecutive ejaculations by sexually experienced male rats had important effects on the physiological responses of the ventral prostate. Fast responses were induced as a result of sexual behavior that involved an increase and decrease in androgen receptors after one and four ejaculations, respectively. However, a progressive response was observed in the elevation of mRNA for androgen receptors, which also showed a fast decrease after four ejaculations. All of these changes with the prostate gland occurred in the presence of a sustained elevation of testosterone in the serum that started after two ejaculations. A consideration of these fast-induced changes suggests that the nerve supply plays a key role in prostate physiology during the sexual behavior of male rats

Desarrollo psicocultural de niños mexicanos

En México habitan más de 30 millones de niños en contextos urbanos, rurales o indígenas, con niveles socieconómicos diferentes, que comparten múltiples aspectos de una historia milenaria que dio fruto a un país que es una rica mezcla de culturas, etnias y lenguas. Su situación solo se puede estudiar a partir de esta realidad multifacética. Este libro aspira a mejorar la comprensión de los diversos aspectos socioculturales que afectan el desarrollo psicológico y la vida de los niños mexicanos. Para ello, se presenta una panorámica de contextos y situaciones particulares que permiten identificar cómo en la niñez la historia individual o grupal tiene implicaciones relevantes en los aprendizajes, el comportamiento social y la evolución emocional y cognitiva. Asimismo, se brindan pistas para entender y atender mejor las necesidades de los niños en México, ya sea en el seno familiar, el ámbito escolar o a través de la implementación de políticas públicas efectivas.ITESO, A.C