La educación y la cultura urbana: aprender a participar en procesos de mejora urbana. Proyecto educativo: Canillejas imagina un parque.

Presentamos una reflexión sobre el papel de la Educación a partir de las lecciones de la experiencia ' Canillejas imagina un Parque' , un proyecto educativo dirigido por Otro Hábitat en colaboración con el Colegio La Alameda , que busca animar a los alumnos a participar en un proceso de diseño e intervención colectiva para transformar un solar enfrente del colegio. Fa vorecer la participación de los niños en la mejora de su entorno urbano puede ser una estrategia clave para hacer frente a las desigualdades urbanas y generar un entendimiento común sobre la responsabilidad de todos en el desarrollo sostenible de nuestras ciudade

Differential Gene Susceptibility to Sperm DNA Damage: Analysis of Developmental Key Genes in Trout

Palabras clave extraídas de la publicación[EN] Sperm chromatin in mammals is packaged in different blocks associated to protamines (PDNA), histones (HDNA), or nuclear matrix proteins. Differential packaging has been related to early or late transcription and also to differential susceptibility to genotoxic damage. Genes located in the more accessible HDNA could be more susceptible to injuries than those located in PDNA, being potential biomarkers of paternal DNA damage. Fish sperm chromatin organization is much diversified, some species lacking protamines and some others totally depleted of histones. Analyzing genotoxic damage in a species homogeneously compacted with some sperm nuclear basic protein type, could help in deciphering the clues of differential susceptibility to damage. In the present study we analyzed in rainbow trout the differential susceptibility of nine genes to UV irradiation and H2O2 treatment. The absence of histones in the sperm nuclei was confirmed by Western blot. The chromatin fractionation in sensitive and resistant regions to PvuII (presumably HDNA-like and PDNA-like, respectively) revealed that the nine genes locate in the same resistant region. The number of lesions promoted was quantified using a qPCR approach. Location of 8-hydroxyguanosine (8-OHdG) was analyzed by immunocytochemistry and confocal microscopy. UV irradiation promoted similar number of lesions in all the analyzed genes and a homogenous distribution of 8- OHdG within the nuclei. 8-OHdG was located in the peripheral area of the nucleus after H2O2 treatment, which promoted a significantly higher number of lesions in developmental-related genes (8.76-10.95 lesions/10 kb) than in rDNA genes (1.05-1.67 lesions/10 kb). We showed for the first time, that differential susceptibility to damage is dependent on the genotoxic mechanism and relies on positional differences between genes. Sensitive genes were also analyzed in cryopreserved sperm showing a lower number of lesions than the previous treatments and a predominant peripheral distribution of oxidative damage (8-OHdG)SIThis work was supported by the Junta de Castilla y León (Spain) (project LE365A11-2 and EDU/828/2014), the Spanish Ministry of Economy and Competitiveness (project AGL2011-27787) and Fondo Social Europeo. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip

Fracturas de astrágalo

Estudio retrospectivo de 63 fracturas de astrágalo recogidas durante un periodo de 13 años. De las 31 fracturas del cuello astragalino se obtuvo un seguimiento de 2 años en 23 de ellas, pudiéndose valorar la aparición en la radiología del signo de Hawkins entre la 6ª y 8ª semana después del traumatismo y el desarrollo o no de necrosis avascular. Se concluye con el estudio que la observación del signo de Hawkins garantiza la correcta perfusión del astrágalo (sensibilidad del 100%). Sin embargo, la no detección de dicho signo no es predictiva del desarrollo de necrosis.Estudi retrospectiu de 63 fractures d'astràgal recollides durant un període de 13 anys. De les 31 fractures del coll astragalí es va obtenir un seguiment de 2 anys en 23 de elles, valorant-ne l'aparició del signe de Hawkins entre la 6ª i la 8ª setmana després del traumatisme i el desenvolupament o no de necrosis avascular. La conclusió de l'estudi és que l'observació del signe de Hawkins garanteix la correcta perfusió de l'astràgal (sensibilitat del 100%). Però la no detecció d'aquest signe no és predictiu del desenvolupament de necrosi

Quality of frozen-thawed semen in brown bear is not affected by timing of glycerol addition

P. 1561-1565We have tested several freezing protocols for brown bear semen, modifying the time when glycerol was added (before and after cooling to 5 °C). No differences were found among protocols, indicating a good tolerance of brown bear semen to glycerol. This finding indicates that freezing protocols for brown bear semen could be modified to fit practical solutions which would facilitate preparation of the seminal samples in the field with the addition of glycerol at ambient temperature.S

DNA fragmentation assessment by flow cytometry and Sperm–Bos–Halomax (bright‐field microscopy and fluorescence microscopy) in bull sperm

P. 88-98The aim of this study was to find the relationship between fertility (as 90‐day non‐return rates) and DNA fragmentation assessed by two techniques [sperm chromatin structure assay (SCSA) and Sperm–Bos–Halomax (SBH)]. Furthermore, other quality parameters were achieved (motility, morphological abnormalities, cytoplasmic droplets, viability, capacitation and acrosomal and mitochondrial status) and their correlations with fertility were analysed. Bulls were divided into three fertility groups: high [non‐return rate (NRR) ≥ 80], medium (80  40). The results of this study indicate that there is a good correlation between fertility and different parameters of sperm quality (SBH and SCSA parameters, % of spermatozoa with head, neck and total abnormalities, and % of spermatozoa with proximal cytoplasmic droplets) and differences between fertility groups were observed in some of them (SBH and SCSA parameters and % of spermatozoa with head, neck and total abnormalities). In this sense, SBH parameters rendered good correlations with fertility (r = −0.42 using bright light microscope and r = −0.47 with fluorescence). Also, standard deviation of DNA fragmentation index (SD‐DFI) and DFIh (cells with High DNA fragmentation index) showed good correlations with fertility (r = −0.41 and r = −0.29). No correlations were observed between SCSA and SBH parameters. A multiple regression shows that four parameters (% of proximal cytoplasmic droplets, % of intact acrosomes in total population, SD‐DFI and percentage of fragmented DNA detected by bright light microscope) present a good predictive value of the fertility of sperm samples (r2 = 0.34, p < 0.001

Effect of basic factors of extender composition on post-thawing quality of brown bear electroejaculated spermatozoa

P. 643-651The improvement of freezing extenders is critical when defining sperm cryopreservation protocols for wild species, in order to create germplasm banks. The aim of this study was to evaluate the effect of additives (Equex Paste and EDTA) supplementation, egg-yolk (10 and 20%) and glycerol (4 and 8%) concentrations and extender osmolality (300 and 320 mOsm/kg) on the post-thawing quality of brown bear semen. Semen was obtained from 20 adult males by electroejaculation, and centrifugated individually (600 × g for 6 min). The pellets were diluted 1:1 in the corresponding extender TTF (TES-Tris-Fructose with the aforementioned variants) and cooled to 5 °C. Then, it was diluted down to 100 × 106 spz/mL, loaded in 0.25 mL straws and frozen at −20°C/min. After thawing (in water at 65 °C for 6s), the semen samples were assessed for motility (CASA), viability (SYBR-14 with propidium iodide), acrosomal status (PNA-FITC with propidium iodide) and mitochondrial activity (JC-1). Extender supplementation with additives rendered significantly higher results for these sperm parameters. Comparing the two percentages of egg yolk, 20% egg yolk showed the highest motility results, percentages of viable spermatozoa and viable spermatozoa with intact acrosome. No differences were detected among samples frozen using 4 or 8% glycerol. For extender osmolality, 300 mOsm/kg showed higher values of VAP, VCL, VSL, and ALH than 320 mOsm/kg. Based on the best performance of sperm motility, viability and acrosome status, we conclude that the most suitable extender to cryopreserve brown bear spermatozoa was TTF adjusted to 300 mOsm/kg, supplemented with 20% egg yolk, 4–8% glycerol, and the additives 1% Equex paste and 2% EDTA.S

Specificity of the extender used for freezing ram sperm depends of the spermatozoa source (ejaculate, electroejaculate or epididymis)

P. 145-154The objective of this study was to identify possible specificity in the extender formulation for the cryopreservation of ram spermatozoa recovered from three origins (ejaculate, electroejaculate or epididymis), by evaluating post-thawing sperm quality and fertility. Ejaculated, electroejaculated or epididymal spermatozoa samples obtained from identical rams (8) were cryopreserved in four different extenders (TES-Tris–fructose with one of two egg yolk concentrations: 10% Y10 and 20% Y20, and with one of two glycerol rates: 4% G4 and 8% G8). Samples were analyzed before and after cryopreservation by CASA (motility) and flow cytometry (viability with SYBR-14/PI and acrosomal status with PNA/PI). Spermatozoa obtained by electroejaculation were of poorer quality after freezing/thawing, demonstrating that protocols for these samples need to be optimized. Egg yolk at 20% was more appropriate for freezing sperm from any of the sources. In general, 4% glycerol improved the quality of post-thawing samples recovered from ejaculate and electroejaculate, while 8% glycerol was more appropriate for samples recovered from the epididymis. Based on these results, an analysis of fertility was conducted. Fertility rates were similar between ewe groups inseminated with post-thawed sperm obtained from two sources: ejaculate (cryopreserved in Y20 + G4), and cauda epididymis (Y20 + G8), and this rate was less in the electroejaculated sample (Y20 + G4)S

Effects on brown bear (Ursus arctos) spermatozoa freezability of different extender and dilution ratios used for pre-freezing centrifugation

P. 259–266The objective of this study was to determine how the extender and dilution ratio used during centrifugation affect bear spermatozoa quality before and after freezing–thawing. Semen was collected from 15 brown bears by electroejaculation. In experiment 1, semen was divided into five aliquots and diluted using one of the following extenders: Tris-citric-glucose (TCG), Tris-citric-glucose-3% BSA, Tris-citric-glucose-1% egg yolk or CaninePro. In experiment 2, semen was divided into five aliquots and diluted 1:1, 1:4, 1:8 or 1:16 (semen:extender) with Tris-citric-glucose. In both experiments, one aliquot was left undiluted and it was used as a control. All the aliquots were centrifuged at 600×g for 6 min and frozen. Samples were analysed by post-thawing for motility (CASA) and, by flow cytometry, for viability (YO-PRO-1), acrosomal status (PNA-FITC/PI) and mitochondrial status (JC-1). CaninePro rendered the highest motility with respect to the undiluted control (total motility, 53.1% vs. 38.5%, P < 0.001), and CaninePro and TCG significantly increased the percentage of viable and acrosome-intact spermatozoa (43.2 and 43.4, respectively, vs. 39.4, P < 0.05). In experiment 2, dilution 1:4 yielded the highest value of total motility (78.8 vs. 67.2, P < 0.05) and proportion of spermatozoa with intact membrane and acrosome (64.5 vs. 54.4, P < 0.01). In general, diluting 1:4 or 1:8 brown bear semen prior to centrifugation improved the motility and acrosome status of the thawed spermatozoa

Chiral and achiral 1D copper(ii) coordination polymers based on glycolato and chelating aromatic diamine ligands

Achiral glycolic acid and chelating aromatic diamine ligands were employed at room temperature to prepare five 1D copper(II) coordination polymers which were structurally characterized. The polymers ∞1{[Cu(HG)(dipyam)](HG)} (1) (dipyam = 2,2'-dipyridylamine) and ∞1 [Cu(HG)(ClO4)(NN)] (NN = 2,2’-bipyridine (2), NN = 1,10-phenanthroline (3)) adopt homochiral helical structures in the crystal state and undergo spontaneous chiral resolution in the solid state. On the other hand, the polymers containing bidepronated glycolato ligand G, ∞1{[Cu(G)(dipyam)]·H2O} (1a), obtained from a solution of 1 in MeOH/iPrOH and ∞1{[Cu2(μ-G)(ClO4)(H2O)(dipyam)2](ClO4)(H2O)2} (4b) are achirals. Crystals of 4b have been obtained together with crystals of the molecular complex [Cu(HG)(H2O)(dipyam)](ClO4) (4a). Analysis by Hirshfeld surface generation and two-dimensional fingerprinting was carried out to study the nature of the interactions and their contributions towards the crystal packing.Ministerio de Economía y Competitividad | Ref. CTQ2015-71211- REDTXunta de Galicia | Ref. ED431D 2017/0

Analysis of discursive patterns for curricular contextualization

[Abstract] With the application of remote education due to the pandemic, Ecuadorian teachers contextualized the curriculum to the needs of their students. The objective was to analyse emerging dialogue patterns during the COVID-19 pandemic, focusing on teachers’ experiences and stories about their interaction with their students. The research was qualitative in which the method of indirect observation of the transcription of 73 semi-structured interviews with teachers from educational institutions in Ecuador was applied through the Zoom platform. To analyze the results, they were categorized and conceptualized following the triple pattern of dialogue and discourse proposed by Mehan in its three dimensions: initiation, response and evaluation. Three phases were established: construction of the final indirect observation instrument; quality control of the information so that there is no subjectivity through the agreement of the criteria of three research authors; and the interpretation of indirect observation through contextualization by curricular contents, methodological strategies and didactic resources. It is revealed that teachers demonstrated remarkable adaptation during the COVID-19 pandemic, focusing on emotional containment and creativity