53 research outputs found

    Pensadero de maestros: a reflective practice teacher dynamic

    Get PDF
    La práctica reflexiva se torna esencial cuando de fortalecimiento docente y mejora educativa se trata. Por ello, parece relevante investigar y proponer acciones que fomenten esta práctica en el quehacer profesional docente. Este artículo presenta la evaluación y validación del proyecto piloto “Pensadero de maestros”, una iniciativa de la Fundación Promaestro para fomentar y apoyar la práctica reflexiva en maestros y profesores. Este proyecto se implementó en seis centros educativos en la Comunidad de Madrid, participando un total de 67 profesores. La investigación siguió una metodología cualitativa basada en el análisis del discurso, utilizando dos técnicas: la entrevista semiestructurada y el grupo de discusión (se realizaron cuatro entrevistas y un grupo de discusión). También se pasó un cuestionario de satisfacción a todos los participantes para triangular la información. Los principales resultados obtenidos confirman que, a través de la observación en el aula y el feedback entre compañeros, los docentes que han pasado por esta dinámica se sienten más reconocidos, acompañados y valorados en su quehacer profesional. La capacidad reflexiva y la validación de prácticas educativas han sido dos procesos conseguidos que han aumentado la autopercepción profesional de los participantes, fomentando el desarrollo y fortalecimiento de la profesión docente. Finalmente, en las discusiones finales se plantean nuevas líneas de investigación en torno al concepto de práctica reflexiva en la profesión docente.Currently, reflective practice is critical to teacher empowerment and educational improvement. Thus, researching and proposing actions focused on this kind of practice in teacher tasks are pertinent activities. This paper evaluates and validates a pilot project, which is named“ Pensadero de Maestros”. It is a Promaestro Foundation initiative, which promotes reflective practice in teachers. This project was launched in six centers from Madrid and 67 teachers participated in it. This research was developed by qualitative methodology, which is based on discourse analysis. Research techniques were semi-structured interview and focus group (four interviews and one focus group were done). Also, a satisfaction questionnaire was given all participants to complete research information. Foundation project has a methodology based on peer observation and professional feedback. Teachers who have took part in this dynamic feel more recognized, more coupled and more valued. Reflective capacity and educational practices validation have been key process to theses teachers. This kind of proposal empowers teacher professional own-perception. Finally, in final discussions new research areas are advanced, which are targeted teacher profession and reflective practice

    Self-cleaning in an estuarine area formerly affected by 226Ra anthropogenic enhancements: numerical simulations

    Get PDF
    A numerical model of the Odiel–Tinto estuary (Spain) has been developed to study the self-cleaning process that was evidenced from 226Ra measurements in water and sediments collected in the period 1999–2002, after direct releases from a fertilizer complex ceased (in 1998). The hydrodynamic model is first calibrated, and standard tidal analysis is carried out to calculate tidal constants required by the dispersion code to determine instantaneous water currents and elevations over the estuary. In this way, long-term simulations may be carried out. The dispersion code includes advective/diffusive transport of radionuclides plus exchanges with bottom sediments described through a kinetic approach. The dispersion model is first tested by comparing computed and measured 226Ra concentrations over the estuary resulting after releases in the Odiel and Tinto rivers. Next, it is applied to simulate the self-cleaning process of the estuary. The time evolution of radium concentrations in bed sediments is in generally good agreement with observations. The computed sediment halving time of the estuary is 510 days, which also is in good agreement with that estimated from measurement

    Self-cleaning in an estuarine area formerly affected by 226Ra anthropogenic enhancements

    Get PDF
    The estuary of the Odiel River has been affected by both direct discharges of phosphogypsum (radium enriched industrial waste) and dissolution and weathering of the exposed piles where this radium enriched waste was stored. In 1998 the waste management policy for industries changed. The direct discharges stopped and the new phosphogypsum piles were well protected against dissolution processes, avoiding any transference of radium into the environment. This work presents a study of the evolution with time (1999–2002) of the levels of 226Ra in river water and sediment samples with the new waste management policy. A liquid scintillation technique was used to measure the 226Ra activity concentration in sediment samples. A gas-proportional counter was also used to measure the 226Ra activity concentration in river water samples. The main conclusion is that a systematic and continuous decrease of the activity concentration of 226Ra with time in the Odiel River estuary is occurring. Thus, a possible self-cleaning in the estuary, once the direct waste discharges were avoided, can be inferred

    Luminal Rank loss decreases cell fitness leading to basal cell bipotency in parous mammary glands

    Get PDF
    Rank signaling pathway regulates mammary gland homeostasis and epithelial cell differentiation. Although Rank receptor is expressed by basal cells and luminal progenitors, its role in each individual cell lineage remains unclear. By combining temporal/lineage specific Rank genetic deletion with lineage tracing techniques, we found that loss of luminal Rank reduces the luminal progenitor pool and leads to aberrant alveolar-like differentiation with high protein translation capacity in virgin mammary glands. These Rank-deleted luminal cells are unable to expand during the first pregnancy, leading to lactation failure and impairment of protein synthesis potential in the parous stage. The unfit parous Rank-deleted luminal cells in the alveoli are progressively replaced by Rank-proficient cells early during the second pregnancy, thereby restoring lactation. Transcriptomic analysis and functional assays point to the awakening of basal bipotency after pregnancy by the induction of Rank/NF-kappa B signaling in basal parous cell to restore lactation and tissue homeostasis. Rocha and co-authors show that loss of luminal Rank signaling causes abnormal alveolar differentiation and lactation failure. Subsequent pregnancies activate bipotency in basal cells, replacing unfit luminal cells, and restoring lactation

    Adult Sox2+ stem cell exhaustion in mice results in cellular senescence and premature aging

    Get PDF
    Aging is characterized by a gradual functional decline of tissues with age. Adult stem and progenitor cells are responsible for tissue maintenance, repair, and regeneration, but during aging, this population of cells is decreased or its activity is reduced, compromising tissue integrity and causing pathologies that increase vulnerability, and ultimately lead to death. The causes of stem cell exhaustion during aging are not clear, and whether a reduction in stem cell function is a cause or a consequence of aging remains unresolved. Here, we took advantage of a mouse model of induced adult Sox2+ stem cell depletion to address whether accelerated stem cell depletion can promote premature aging. After a short period of partial repetitive depletion of this adult stem cell population in mice, we observed increased kyphosis and hair graying, and reduced fat mass, all of them signs of premature aging. It is interesting that cellular senescence was identified in kidney after this partial repetitive Sox2+ cell depletion. To confirm these observations, we performed a prolonged protocol of partial repetitive depletion of Sox2+ cells, forcing regeneration from the remaining Sox2+ cells, thereby causing their exhaustion. Senescence specific staining and the analysis of the expression of genetic markers clearly corroborated that adult stem cell exhaustion can lead to cellular senescence induction and premature agingWork in the laboratory of M.C. is funded by an ISCIII and EU‐FEDER grant (PI14/00554)S

    Context-dependent impact of RAS oncogene expression on cellular reprogramming to pluripotency

    Get PDF
    Induction of pluripotency in somatic cells with defined genetic factors has been successfully used to investigate the mechanisms of disease initiation and progression. Cellular reprogramming and oncogenic transformation share common features; both involve undergoing a dramatic change in cell identity, and immortalization is a key step for cancer progression that enhances reprogramming. However, there are very few examples of complete successful reprogramming of tumor cells. Here we address the effect of expressing an active oncogene, RAS, on the process of reprogramming and found that, while combined expression with reprogramming factors enhanced dedifferentiation, expression within the context of neoplastic transformation impaired reprogramming. RAS induces expression changes that promote loss of cell identity and acquisition of stemness in a paracrine manner and these changes result in reprogramming when combined with reprogramming factors. When cells carry cooperating oncogenic defects, RAS drives cells into an incompatible cellular fate of malignancy.A.F. is an FPU predoctoral fellow from MECD; P.P. and J.M.V. are predoctoral fellows from Xunta de Galicia; F.T.-M. is a postdoctoral fellow from CONACYT (cvu 268632). M.C. is a ‘‘Miguel Servet II’’ investigator (CPII16/00015). Work in the laboratory of M.C. is funded by an ISCIII and EU-FEDER grant (PI14/00554). Work in the laboratory of A.V. is funded by Xunta de Galicia (ED431B 2016) and MINECO (MAT2017-89678-R; cofinanced with FEDER Funds)S

    RANK links senescence to stemness in the mammary epithelia, delaying tumor onset but increasing tumor aggressiveness

    Get PDF
    Rank signaling enhances stemness in mouse and human mammary epithelial cells (MECs) and mediates mammary tumor initiation. Mammary tumors initiated by oncogenes or carcinogen exposure display high levels of Rank and Rank pathway inhibitors have emerged as a new strategy for breast cancer prevention and treatment. Here, we show that ectopic Rank expression in the mammary epithelia unexpectedly delays tumor onset and reduces tumor incidence in the oncogene-driven Neu and PyMT models. Mechanistically, we have found that ectopic expression of Rank or exposure to Rankl induces senescence, even in the absence of other oncogenic mutations. Rank leads to DNA damage and senescence through p16/p19. Moreover, RANK-induced senescence is essential for Rank-driven stemness, and although initially translates into delayed tumor growth, eventually promotes tumor progression and metastasis. We uncover a dual role for Rank in the mammary epithelia: Rank induces senescence and stemness, delaying tumor initiation but increasing tumor aggressiveness

    Identification and characterization of Cardiac Glycosides as senolytic compounds

    Get PDF
    Compounds with specific cytotoxic activity in senescent cells, or senolytics, support the causal involvement of senescence in aging and offer therapeutic interventions. Here we report the identification of Cardiac Glycosides (CGs) as a family of compounds with senolytic activity. CGs, by targeting the Na+/K+ATPase pump, cause a disbalanced electrochemical gradient within the cell causing depolarization and acidification. Senescent cells present a slightly depolarized plasma membrane and higher concentrations of H+, making them more susceptible to the action of CGs. These vulnerabilities can be exploited for therapeutic purposes as evidenced by the in vivo eradication of tumors xenografted in mice after treatment with the combination of a senogenic and a senolytic drug. The senolytic effect of CGs is also effective in the elimination of senescence-induced lung fibrosis. This experimental approach allows the identification of compounds with senolytic activity that could potentially be used to develop effective treatments against age-related diseases.We thank Matthias Drosten, Alejo Efeyan and Sean Morrison for plasmids. F.T-M. is a postdoctoral fellow from CONACYT (cvu 268632); P.P. is a predoctoral fellow from Xunta de Galicia; M.C. is a "Miguel Servet II" investigator (CPII16/00015). P.P.-R. receives support from a program by the Deputacion de Coruna (BINV-CS/2019). Work in the laboratory of M.C. is funded by grant RTI2018-095818-B-100 (MCIU/AEI/FEDER, UE). P.J.F.-M. is funded by the IMDEA Food Institute, the Ramon Areces Foundation, (CIVP18A3891), and a Ramon y Cajal Award (MICINN) (RYC-2017-22335). M.P.I. is funded by Talento Modalidad-1 Program Grant, Madrid Regional Government (#2018-T1/BIO-11262). F.P. was funded by a Long Term EMBO Fellowship (ALTF-358-2017) and F.H-G. was funded by the PhD4MD Programme of the IRB, Hospital Clinic and IDIBAPS. Work in the laboratory of M.S. was funded by the IRB and by grants from the Spanish Ministry of Economy co-funded by the European Regional Development Fund (ERDF) (SAF2013-48256-R), the European Research Council (ERC-2014-AdG/669622), and "laCaixa" Foundation.S

    IgA vasculitis: influence of CD40, BLK and BANK1 gene polymorphisms

    Get PDF
    CD40, BLK and BANK1 genes involved in the development and signaling of B-cells are identified as susceptibility loci for numerous inflammatory diseases. Accordingly, we assessed the potential influence of CD40, BLK and BANK1 on the pathogenesis of immunoglobulin-A vasculitis (IgAV), predominantly a B-lymphocyte inflammatory condition. Three genetic variants within CD40 (rs1883832, rs1535045, rs4813003) and BLK (rs2254546, rs2736340, rs2618476) as well as two BANK1 polymorphisms (rs10516487, rs3733197), previously associated with inflammatory diseases, were genotyped in 382 Caucasian patients with IgAV and 955 sex- and ethnically matched healthy controls. No statistically significant differences were observed in the genotype and allele frequencies of CD40, BLK and BANK1 when IgAV patients and healthy controls were compared. Similar results were found when CD40, BLK and BANK1 genotypes or alleles frequencies were compared between patients with IgAV stratified according to the age at disease onset or to the presence/absence of gastrointestinal or renal manifestations. Moreover, no CD40, BLK and BANK1 haplotype differences were disclosed between patients with IgAV and healthy controls and between patients with IgAV stratified according to the clinical characteristics mentioned above. Our findings indicate that CD40, BLK and BANK1 do not contribute to the genetic background of IgAV.Funding: This study was supported by European Union FEDER funds and “Fondo de Investigaciones Sanitarias” (grants PI18/00042 and PI21/00042) from “Instituto de Salud Carlos III” (ISCIII, Health Ministry, Spain). D.P.-P. is a recipient of a Río Hortega program fellowship from the ISCIII, co-funded by the European Social Fund (ESF, “Investing in your future”) (grant number CM20/00006). F.G. is supported by funds of the RICORS Program from ISCIII, co-funded by the European Union (grant number RD21/0002/0025). V.P.-C. is supported by funds of PI18/00042. S.R.-M. is supported by funds of the RETICS Program (RD16/0012/0009) (ISCIII, co-funded by the European Regional Development Fund (ERDF)). O.G. is a staff member of Xunta de Galicia (Servizo Galego de Saude (SERGAS)) through a research-staff stabilization contract (ISCIII/SERGAS) and his work is funded by ISCIII and the European Union FEDER fund (grant numbers RD16/0012/0014 (RIER) and PI17/00409). He is a beneficiary of project funds from the Research Executive Agency (REA) of the European Union in the framework of MSCA-RISE Action of the H2020 Program, project 734899—Olive-Net. R.L.-M. is a recipient of a Miguel Servet type II program fellowship from the ISCIII, co-funded by ESF (“Investing in your future”) (grant number CPII21/00004). Acknowledgments: We are indebted to the patients and healthy controls for their essential collaboration on this study. We also thank the National DNA Bank Repository (Salamanca) for supplying part of the control samples
    corecore