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La pandemia del coronavirus SARS-COV-2, y su enfermedad asociada la Covid-19, ha generado un alto costo de vidas humanas, y crisis en el sistema de salud mexicano. Entre las vidas humanas afectadas se encuentran algunos elementos del personal médico y sanitario quienes realizaron su labor en un sistema de salud ya desde antes deteriorado y en condiciones de trabajo no aptas.Los trabajadores de la salud tienen derecho a la seguridad en el trabajo y el Estado mexicano y las autoridades sanitarias tienen la obligación de velar por las necesidades del personal médico y sanitario además de garantizar la seguridad de estos trabajadores. Por tanto, tienen responsabilidad así sea por falta de inversión, preparación e infraestructura inadecuada en el diseño del sistema de salud, o por cualquier otra acción irregular del Estado en la toma de decisiones para afrontar la pandemia. En lo individual, las personas afectadas por la acción administrativa irregular del Estado tienen derecho a una indemnización legal.

Thyroid hormones are messengers that bind to specific nuclear receptors and regulate a wide range of physiological processes in the early stages of vertebrate embryonic development, including neurodevelopment and myelogenesis. We here tested the effects of reduced T3 availability upon the myelination process by treating zebrafish embryos with low concentrations of iopanoic acid (IOP) to block T4 to T3 conversion. Black Gold II staining showed that T3 deficiency reduced the myelin density in the forebrain, midbrain, hindbrain and the spinal cord at 3 and 7 dpf. These observations were confirmed in 3 dpf mbp:egfp transgenic zebrafish, showing that the administration of IOP reduced the fluorescent signal in the brain. T3 rescue treatment restored brain myelination and reversed the changes in myelin-related gene expression induced by IOP exposure. NG2 immunostaining revealed that T3 deficiency reduced the amount of oligodendrocyte precursor cells in 3 dpf IOP-treated larvae. Altogether, the present results show that inhibition of T4 to T3 conversion results in hypomyelination, suggesting that THs are part of the key signaling molecules that control the timing of oligodendrocyte differentiation and myelin synthesis from very early stages of brain development. ispartof: PLOS ONE vol:16 issue:8 ispartof: location:United States status: published

Ecotoxicological studies are necessary in order to evaluate the effects of environmental exposure of chemicals on wild animals and their ecological consequences. Particularly, neurobehavioral effects of heavy metal elements on wild rodents have been scarcely investigated. In the present study, we analyzed the effect of metal bioaccumulation (Pb, As, Mg, Ni, and Zn) in the brain and in the liver on exploratory activity, learning, memory, and on some dopaminergic markers in the wild rodent Liomys irroratus living inside mine tailings, at Huautla, Morelos, Mexico. We found higher Pb concentration but lower Zn in striatum, nucleus accumbens, midbrain, and hippocampus in exposed animals in comparison to rodents from the reference site. Exposed rodents exhibited anxious behavior evaluated in the open field, while no alterations in learning were found. However, they displayed slight changes in the memory test in comparison to reference group. The neurochemical evaluation showed higher levels of dopamine and 5-hydroxyindolacetic acid in midbrain, while lower levels of metabolites dihydroxyphenyl acetic acid and homovanillic acid in striatum of exposed rodents. In addition, mRNA expression levels of dopaminergic D2 receptors in nucleus accumbens were lower in animals from the mining zone than in animals from the reference zone. This is the first study that shows that chronic environmental exposure to metals results in behavioral and neurochemical alterations in the wild rodent L. irroratus, a fact that may comprise the survival of the individuals resulting in long-term effects at the population level. Finally, we suggest the use of L. irroratus as a sentinel species for environmental biomonitoring of mining sites.

In contrast to mammalian adults, myelination in teleosts occurs throughout their lifespan and most of the progenitor cells are originated in the cerebellum. To understand the role that thyroid hormones (THs) play in juvenile cerebellar myelination in teleosts, we identified and localised the expression of genes involved in TH signalling (mct8, oatp1c1, dio2, dio3, thraa and l-thrb1) and analysed the effects of the two bioactive THs, T2 and T3, upon their regulation, as well as upon some structural components of the myelination process. Ex vivo approaches using organotypic cerebellar cultures followed by FISH and qPCR showed gene-specific localisation and regulation of TH signalling genes in the cerebellar nuclei. In vivo approaches using methimazole (MMI)-treated juvenile tilapias replaced with low doses of T3 and T2 showed by immunofluorescence that myelin fibres in the cerebellum are more abundant in the granular layer and that their visible size is reduced after MMI treatment but partially restored with TH replacement, suggesting that low doses of TH promote the re-myelination process in an altered condition. Together, our data support the idea that T2 and T3 promote myelination via different pathways and prompt T2 as a target for further analysis as a promising therapy for hypomyelination.

T3 and cortisol activate or repress gene expression in virtually every vertebrate cell mainly by interacting with their nuclear hormone receptors. In contrast to the mechanisms for hormone gene activation, the mechanisms involved in gene repression remain elusive. In teleosts, the thyroid hormone receptor beta gene or thrb produces two isoforms of TRβ1 that differ by nine amino acids in the ligand-binding domain of the long-TRβ1, whereas the short-TRβ1 lacks the insert. Previous reports have shown that the genomic effects exerted by 3,5-T2, a product of T3 outer-ring deiodination, are mediated by the long-TRβ1. Furthermore, 3,5-T2 and T3 down-regulate the expression of long-TRβ1 and short-TRβ1, respectively. In contrast, cortisol has been shown to up-regulate the expression of thrb. To understand the molecular mechanisms for thrb modulation by thyroid hormones and cortisol, we used an in silico approach to identify thyroid- and cortisol-response elements within the proximal promoter of thrb from tilapia. We then characterized the identified response elements by EMSA and correlated our observations with the effects of THs and cortisol upon expression of thrb in tilapia. Our data show that 3,5-T2 represses thrb expression and impairs its up-regulation by cortisol possibly through a transrepression mechanism. We propose that for thrb down-regulation, ligands other than T3 are required to orchestrate the pleiotropic effects of thyroid hormones in vertebrates.

El disfrute de la seguridad social no solo permite que los ciudadanos se desarrollen en una sociedad habitable, sino que fomenta la inclusion social y posibilita que todos puedan participar en los acontecimientos sociales y politicos de un pais. Algunos de esos acontecimientos, que —en principio no tienen relacion directa con el otorgamiento de prestaciones de los derechos sociales— inciden indirectamente en el desarrollo o involucion de la seguridad social. Dentro de ellos se pueden mencionar como los mas importantes para el 2016 los siguientes: la reforma sobre igualdad de derechos para todos los ciudadanos mexicanos, el avance legislativo anticorrupcion y la visita del papa Francisco, los cuales se describen brevemente como parte del contexto social que vivio Mexico en 2016. El objetivo de este informe es brindar de forma sintetica una semblanza de los principales cambios registrados en Mexico en materia de seguridad social durante un periodo especifico: el 2016, con la intencion de mantener un registro analitico sobre el proceso de desarrollo que se va presentando en el pais, para hacer con el un balance entre los cambios efectuados y los desafios pendientes ano con ano.

RESUMENEl presente artículo analiza el fenómeno de la migración laboral controlada, como es el caso del Programa de Trabajadores Agrícolas Temporales, celebrado entre México y Canadá. El tema es abordado desde los puntos de vista jurídico y sociológico; a través de consultas de acceso a la información se permitió analizar documentos y situaciones reales y concretas. Asimismo, a más de 40 años de la celebración del memorándum de entendimiento entre nuestro país y Canadá, se considera relevante realizar un estudio que muestre los cambios que ha tenido el marco normativo en materia de trabajo, así como los cambios en los contratos empleados; igualmente llegar a la comprensión que la globalización y la migración han ido en aumento, y que las condiciones de vida de los jornaleros también se han transformado a pesar de los esfuerzos de las autoridades y de la sociedad civil para la protección de los derechos humanos de los migrantes mexicanos.ABSTRACTThis article analyzes the phenomenon of controlled labor migration, such as the Seasonal Agricultural Workers Program, executed between Mexico and Canada. The issue is addressed from a legal and sociological point of view, through consultations of access to information it was possible to analyze documents and real and specific situations. Besides, more than 40 years of the celebration of the Memorandum of Understanding between our country and Canada, it is considered relevant to conduct a study showing the modifications that the labor regulatory framework and the applying contracts have undergone; moreover, it is important to fully comprehend that both globalization and migration have increased, and that the living conditions of laborers have also changed despite the efforts of authorities and civil society to protect the human rights of Mexican migrants.

The stereospecific removal of iodine from thyroid hormones is an essential first step for T3 action and is catalyzed by three different deiodinases: D2 and D3 remove iodine only from the outer or inner ring, respectively, whereas D1 catalyzes both pathways. We used in silico predictions from vertebrate deiodinase sequences to identify two domains: the N-terminal variable region (VR) containing the transmembrane, hinge and linker domains, and the conserved or globular region (CR). Given the high sequence and structural identity of the CR among paralogs as well as of the VR among orthologs but not paralogs, we hypothesized that both the catalytic properties and the subcellular localization rely on the VR. We used shark D2 and D3 as templates to build the chimeric enzymes D2VR/D3CR and D3VR/D2CR. Biochemical characterization revealed that D3VR/D2CR has inner-ring deiodination activity and T3 as preferred substrate, whereas D2VR/D3CR showed no deiodinating activity. Also, D2VR/D3CR and D3VR/D2CR reside in the endoplasmic reticulum and plasmatic membrane, respectively, as do their D2 and D3 wild-type counterparts. We conclude that the VR determines the subcellular localization and is critical in defining the catalytic properties and activity of thyroid hormone deiodinases.

El siguiente artículo busca discernir sobre la importancia del derecho a la protección de datos personales y el carácter instrumental que éste tiene para el efectivo ejercicio del derecho a la salud. Lo anterior, a partir de la explicación de los alcances relativos al acceso y confidencialidad del expediente clínico, en sus modalidades física y electrónica, desde la óptica de la legislación aplicable, los criterios abordados al respecto en el ámbito judicial y administrativo, así como el planteamiento de oportunidades y desafíos por afrontar para eficientar su acceso y fortalecer la protección de datos personales.

Growth hormone (GH), together with thyroid hormones (TH), regulates growth and development, and has critical effects on vertebrate metabolism. In ectotherms, these physiological processes are strongly influenced by environmental temperature. In reptiles, however, little is known about the direct influences of this factor on the somatotropic and thyroid axes. Therefore, the aim of this study was to describe the effects of both acute (48h) and chronic (2weeks) exposure to sub-optimal temperatures (25 and 18°C) upon somatotropic and thyroid axis function of the green iguana, in comparison to the control temperature (30-35°C). We found a significant increase in GH release (2.0-fold at 25°C and 1.9-fold at 18°C) and GH mRNA expression (up to 3.7-fold), mainly under chronic exposure conditions. The serum concentration of insulin-like growth factor-I (IGF-I) was significantly greater after chronic exposure (18.5±2.3 at 25°C; 15.92±3.4 at 18°C; vs. 9.3±1.21ng/ml at 35°C), while hepatic IGF-I mRNA expression increased up to 6.8-fold. Somatotropic axis may be regulated, under acute conditions, by thyrotropin-releasing hormone (TRH) that significantly increased its hypothalamic concentration (1.45 times) and mRNA expression (0.9-fold above control), respectively; and somatostatin (mRNA expression increased 1.0-1.2 times above control); and under chronic treatment, by pituitary adenylate cyclase-activating peptide (PACAP mRNA expression was increased from 0.4 to 0.6 times). Also, it was shown that, under control conditions, injection of TRH stimulated a significant increase in circulating GH. On the other hand, while there was a significant rise in the hypothalamic content of TRH and its mRNA expression, this hormone did not appear to influence the thyroid axis activity, which showed a severe diminution in all conditions of cold exposure, as indicated by the decreases in thyrotropin (TSH) mRNA expression (up to one-eight of the control), serum T4 (from 11.6±1.09 to 5.3±0.58ng/ml, after 2weeks at 18°C) and T3 (from 0.87±0.09 to 0.05±0.01ng/ml, under chronic conditions at 25°C), and Type-2 deiodinase (D2) activity (from 992.5±224 to 213.6±26.4fmolI(125)T4/mgh). The reduction in thyroid activity correlates with the down-regulation of metabolism as suggested by the decrease in the serum glucose and free fatty acid levels. These changes apparently were independent of a possible stress response, at least under acute exposure to both temperatures and in chronic treatment to 25°C, since serum corticosterone had no significant changes in these conditions, while at chronic 18°C exposure, a slight increase (0.38 times above control) was found. Thus, these data suggest that the reptilian somatotropic and thyroid axes have differential responses to cold exposure, and that GH and TRH may play important roles associated to adaptation mechanisms that support temperature acclimation in the green iguana.