73 research outputs found
Staining of Neuroendocrine Merkel Cells of Human Epidermis Using the Uranaffin Reaction
The uranaffin reaction (UR) stains neurosecretory (NS) granules of the neuroendocrine system under certain experimental conditions of staining and rinsing solutions. Human normal neuroendocrine (NE) Merkel cells stained using the UR exhibit a positive reaction in their NS granules, ribosomes, and nuclear chromatin. The average values of maximum granular diameter (GD = 69.1nm) and area (GA = 3637.8nm2) of NS granules measured in the adult NE Merkel cells stained with UR are significantly greater than those (GD = 61.4nm; GA = 2699.8nm2) seen in the fetal NE Merkel cells also stained with UR. No differences in form factor are found between fetal and adult NS granules. On different samples of human adult and fetal epidermis it is demonstrated that UR is a useful cytochemical marker for the NS granules of normal NE Merkel cells
Diseño, aplicación y evaluación de un tutorial para elaborar páginas web educativas
Con este proyecto hemos pretendido introducir a los alumnos de las asignaturas de Nuevas
Tecnologías aplicadas a la educación y Tecnología Educativa en el mundo de la elaboración de páginas
web, siempre desde el punto de vista educativo. Para ello, hemos elaborado una web tutorial
en la que se indica paso a paso cada una de las etapas en la creación de las mismas. Además, la
aplicación de este proyecto se ha llevado a cabo en tres grupos de alumnos diferentes, encontrando
buenos resultados tras la evaluación del mismoWith this project we have sought to introduce the students of the subjects of New Technologies
applied to the education and Educational Technology in the world of the elaboration of pages web,
always from the educational point of view. For it, we have elaborated a web tutorial in which step
is indicated to step each one of the stages in the creation of the same ones. Also, the application
of this project has been carried out in three groups of different students, finding good results after
the evaluation of the same on
Spark plasma sintering of TixTa1-xC0.5N0.5-based cermets: Effects of processing conditions on chemistry, microstructure and mechanical properties
Nanometric powdered TixTa1-xC0.5N0.5-based cermets were fabricated using a mechanically induced self-sustaining reaction and consolidated by spark plasma sintering. Highly dense cermets were obtained, and their chemistry, microstructure and mechanical properties were characterised by X-ray diffraction, scanning electron microscopy, image analysis, microindentation and nanoindentation. The microhardness was found to depend directly on the contiguity and size of the ceramic hard particles. The samples synthesised at the lowest temperature (1150°C) exhibited more homogeneous microstructures and smaller ceramic particles and the best combination of microhardness and fracture toughness.Gobierno de España MAT2011-2298
Histological and histomorphometric study of human palatal mucosa: implications for connective tissue graft harvesting
Aims
To analyse the histological structure and histomorphometric characteristics of human hard palatal mucosa in order to determine the donor site of choice for connective tissue grafts from a histological point of view.
Materials and Methods
Palatal mucosa samples from six cadaver heads were harvested at four sites: incisal, premolar, molar and tuberosity. Histological and immunohistochemical techniques were performed, as was histomorphometric analysis.
Results
In the current study, we found that the density and size of cells were higher in the superficial papillary layer, whereas the thickness of the collagen bundles increased in the reticular layer. Excluding the epithelium, the mean percentage of lamina propria (LP) and submucosa (SM) was 37% and 63%, respectively (p < .001). LP thickness showed similar values in the incisal, premolar and molar regions, and a significantly greater thickness in tuberosity (p < .001). The thickness of SM increased from incisal to premolar and molar, disappearing in the tuberosity (p < .001).
Conclusions
As dense connective tissue of LP is the tissue of choice for connective tissue grafts, the best donor site from a histological point of view is tuberosity because it is composed only of a thick LP without the presence of a loose submucosal layerS
Escape room in the initial training of kindergarten teachers
La Competencia Digital Docente se ha instaurado como una de las habilidades básicas y está
ganando terreno en el campo educativo dentro de un nuevo enfoque en la educación virtual. En
los últimos años, se ha incrementado su presencia en las organizaciones educativas. En este
sentido, esta investigación se centra en el diseño y validación de la estructura, contenido y tareas
de un itinerario formativo para el desarrollo de la Competencia Digital de docentes no
universitarios en base al Marco DigCompEdu de la Unión Europea. Esta investigación se enmarca
en una mayor y, como paso previo a un estudio más amplio, se establece un diseño de validación
tipo Delphi mediante coeficiente experto que cuenta con la participación de 50 personas. Los
resultados demuestran la validez de la propuesta formativa, así como la uniformidad de criterio
de los expertos. En este sentido, se debate la aplicación y beneficios de esta acción formativa
para el desarrollo competencial.Digital Teaching Competence has been established as one of the basic skills and is gaining ground
in the educational field within a new approach to virtual education. In recent years, its presence
in educational organizations has increased. In this sense, this research focuses on the design and
validation of the structure, content and tasks of a training itinerary for the development of the Digital Competence of non-university teachers based on the DigCompEdu Framework of the
European Union. This research is part of a larger one and, as a preliminary step to a broader
study, a Delphi-type validation design is established using an expert coefficient with the
participation of 50 people. The results demonstrate the validity of the training proposal, as well
as the uniformity of criteria of the experts. In this sense, the application and benefits of this
training action for competence development are discussed
Obestatin as a regulator of adipocyte metabolism and adipogenesis
The role of obestatin, a 23-amino-acid peptide encoded by the ghrelin gene, on the control of the metabolism of pre-adipocyte and adipocytes as well as on adipogenesis was determined. For in vitro assays, pre-adipocyte and adipocyte 3T3-L1 cells were used to assess the obestatin effect on cell metabolism and adipogenesis based on the regulation of the key enzymatic nodes, Akt and AMPK and their downstream targets. For in vivo assays, white adipose tissue (WAT) was obtained from male rats under continuous subcutaneous infusion of obestatin. Obestatin activated Akt and its downstream targets, GSK3alpha/beta, mTOR and S6K1, in 3T3-L1 adipocyte cells. Simultaneously, obestatin inactivated AMPK in this cell model. In keeping with this, ACC phosphorylation was also decreased. This fact was confirmed in vivo in white adipose tissue (omental, subcutaneous and gonadal) obtained from male rats under continuous sc infusion of obestatin (24 and 72 hrs). The relevance of obestatin as regulator of adipocyte metabolism was supported by AS160 phosphorylation, GLUT4 translocation and augment of glucose uptake in 3T3-L1 adipocyte cells. In contrast, obestatin failed to modify translocation of fatty acid transporters, FATP1, FATP4 and FAT/CD36, to plasma membrane. Obestatin treatment in combination with IBMX and DEX showed to regulate the expression of C/EBPalpha, C/EBPbeta, C/EBPdelta and PPARgamma promoting adipogenesis. Remarkable, preproghrelin expression, and thus obestatin expression, increased during adipogenesis being sustained throughout terminal differentiation. Neutralization of endogenous obestatin secreted by 3T3-L1 cells by anti-obestatin antibody decreased adipocyte differentiation. Furthermore, knockdown experiments by preproghrelin siRNA supported that obestatin contributes to adipogenesis. In summary, obestatin promotes adipogenesis in an autocrine/paracrine manner, being a regulator of adipocyte metabolism. These data point to a putative role in the pathogenesis of metabolic syndrome
The cold-sensing ion channel TRPM8 regulates central and peripheral clockwork and the circadian oscillations of body temperature
[Abstract] Aim: Physiological functions in mammals show circadian oscillations, synchronized by daily cycles of light and temperature. Central and peripheral clocks participate in this regulation. Since the ion channel TRPM8 is a critical cold sensor, we investigated its role in circadian function.
Methods: We used TRPM8 reporter mouse lines and TRPM8-deficient mice. mRNA levels were determined by in situ hybridization or RT-qPCR and protein levels by immunofluorescence. A telemetry system was used to measure core body temperature (Tc).
Results: TRPM8 is expressed in the retina, specifically in cholinergic amacrine interneurons and in a subset of melanopsin-positive ganglion cells which project to the central pacemaker, the suprachiasmatic nucleus (SCN) of the hypothalamus. TRPM8-positive fibres were also found innervating choroid and ciliary body vasculature, with a putative function in intraocular temperature, as shown in TRPM8-deficient mice. Interestingly, Trpm8-/- animals displayed increased expression of the clock gene Per2 and vasopressin (AVP) in the SCN, suggesting a regulatory role of TRPM8 on the central oscillator. Since SCN AVP neurons control body temperature, we studied Tc in driven and free-running conditions. TRPM8-deficiency increased the amplitude of Tc oscillations and, under dim constant light, induced a greater phase delay and instability of Tc rhythmicity. Finally, TRPM8-positive fibres innervate peripheral organs, like liver and white adipose tissue. Notably, Trpm8-/- mice displayed a dysregulated expression of Per2 mRNA in these metabolic tissues.
Conclusion: Our findings support a function of TRPM8 as a temperature sensor involved in the regulation of central and peripheral clocks and the circadian control of Tc.Ministerio de Ciencia e Innovación (España); RT2018-099995-B100Ministerio de Ciencia e Innovación (España); AEI/10.13039/501100011033Generalitat Valenciana; PROMETEO/2021/031Ministerio de Asuntos Económicos y Transformación Digital (España); BES-2011-04706
A Functional Link between AMPK and Orexin Mediates the Effect of BMP8B on Energy Balance
AMP-activated protein kinase (AMPK) in the ventromedial nucleus of the hypothalamus (VMH) and orexin (OX) in the lateral hypothalamic area (LHA) modulate brown adipose tissue (BAT) thermogenesis. However, whether these two molecular mechanisms act jointly or independently is unclear. Here, we show that the thermogenic effect of bone morphogenetic protein 8B (BMP8B) is mediated by the inhibition of AMPK in the VMH and the subsequent increase in OX signaling via the OX receptor 1 (OX1R). Accordingly, the thermogenic effect of BMP8B is totally absent in ox-null mice. BMP8B also induces browning of white adipose tissue (WAT), its thermogenic effect is sexually dimorphic (only observed in females), and its impact on OX expression and thermogenesis is abolished by the knockdown of glutamate vesicular transporter 2 (VGLUT2), implicating glutamatergic signaling. Overall, our data uncover a central network controlling energy homeostasis that may be of considerable relevance for obesity and metabolic disordersThe research leading to these results received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement 281854 the ObERStress project (M.L.), Junta de Andalucía (M.T.-S., P08-CVI-03788 and P12-FQM-01943), Xunta de Galicia (M.L., 2015-CP079; and R.N., 2015-CP080 and PIE13/00024), MINECO co-funded by FEDER (C.D., BFU2014-55871-P; R.N., BFU2015-70664-R; M.T.-S., BFU2014-57581-P; and M.L., SAF2015-71026-R and BFU2015-70454-REDT/Adipoplast). I.G.-G. is a recipient of a fellowship from Ministerio de Educación, Cultura y Deporte (FPU12/01827). CIBER de Fisiopatología de la Obesidad y Nutrición is an initiative of ISCIII. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptS
Central Ceramide-Induced Hypothalamic Lipotoxicity and ER Stress Regulate Energy Balance
Hypothalamic endoplasmic reticulum (ER) stress is a key mechanism leading to obesity. Here, we demonstrate that ceramides induce lipotoxicity and hypothalamic ER stress, leading to sympathetic inhibition, reduced brown adipose tissue (BAT) thermogenesis, and weight gain. Genetic overexpression of the chaperone GRP78/BiP (glucoseregulated protein 78 kDa/binding immunoglobulin protein) in the ventromedial nucleus of the hypothalamus (VMH) abolishes ceramide action by reducing hypothalamic ER stress and increasing BAT thermogenesis, which leads to weight loss and improved glucose homeostasis. The pathophysiological relevance of this mechanism is demonstrated in obese Zucker rats, which show increased hypothalamic ceramide levels and ER stress. Overexpression of GRP78 in the VMH of these animals reduced body weight by increasing BAT thermogenesis as well as decreasing leptin and insulin resistance and hepatic steatosis. Overall, these data identify a triangulated signaling network involving central ceramides, hypothalamic lipotoxicity/ER stress, and BAT thermogenesis as a pathophysiological mechanism of obesity
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