Inhibitory control of up states and their propagation in the cortical network

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Slow and Fast Neocortical Oscillations in the Senescence-Accelerated Mouse Model SAMP8

The senescence-accelerated mouse prone 8 (SAMP8) model is characterized by accelerated, progressive cognitive decline as well as Alzheimer's disease (AD)-like neurodegenerative changes, and resembles the etiology of multicausal, sporadic late-onset/age-related AD in humans. Our aim was to find whether these AD-like pathological features, together with the cognitive deficits present in the SAMP8 strain, are accompanied by disturbances in cortical network activity with respect to control mice (SAM resistance 1, SAMR1) and, if so, how the alterations in cortical activity progress with age. For this purpose, we characterized the extracellular spontaneous oscillatory activity in different regions of the cerebral cortex of SAMP8 and SAMR1 mice under ketamine anesthesia at 5 and 7 months of age. Under these conditions, slow oscillations and fast rhythms generated in the cortical network were recorded and different parameters of these oscillations were quantified and compared between SAMP8 and their control, SAMR1 mice. The average frequency of slow oscillations in SAMP8 mice was decreased with respect to the control mice at both studied ages. An elongation of the silent periods or Down states was behind the decreased slow oscillatory frequency while the duration of active or Up states remained stable. SAMP8 mice also presented increased cycle variability and reduced high frequency components during Down states. During Up states, the power peak in the gamma range was displaced towards lower frequencies in all the cortical areas of SAMP8 with respect to control mice suggesting that the spectral profile of SAMP8 animals is shifted towards lower frequencies. This shift is reminiscent to one of the principal hallmarks of electroencephalography (EEG) abnormalities in patients with Alzheimer's disease, and adds evidence in support of the suitability of the SAMP8 mouse as a model of this disease. Although some of the differences between SAMP8 and control mice were emphasized with age, the evolution of the studied parameters as SAMR1 mice got older indicates that the SAMR1 phenotype tends to converge with that of SAMP8 animals. To our knowledge, this is the first systematic characterization of the cortical slow and fast rhythms in the SAMP8 strain and it provides useful insights about the cellular and synaptic mechanisms underlying the reported alterations

Sodium tungstate and vanadyl sulfate effects on blood pressure and vascular prostanoids production in fructose-overloaded rats

This study analyzes the effects of sodium tungstate and vanadyl sulphate in the fructose-overloaded rat, a model of metabolic syndrome. Fructose (9 weeks) increased blood pressure, triglycerydemia, glycemia, and reduced release of vasodilator prostaglandins (prostacyclin and prostaglandin E2) in the mesenteric vascular bed. Sodium tungstate prevented those alterations; meanwhile vanadyl sulfate only prevented the increase in glycemia. In conclusion, the present experiments showed that sodium tungstate is more effective than vanadyl sulfate for the treatment of experimental metabolic syndrome in rats.Fil: Peredo, Horacio Angel. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Zabalza, Maria. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Histología y Biología Celular; ArgentinaFil: Mayer, Marcos Alejandro. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Fisiopatología y Bioquímica Clínica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Carranza, Andrea. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Puyó, Ana María. Universidad de Buenos Aires. Facultad de Medicina; Argentin

CLOCK, PER2 and BMAL1 DNA methylation: association with obesity and metabolic syndrome characteristics and monounsaturated fat intake

The circadian clock system instructs 24-h rhythmicity on gene expression in essentially all cells, including adipocytes, and epigenetic mechanisms may participate in this regulation. The aim of this research was to investigate the influence of obesity and metabolic syndrome (MetS) features in clock gene methylation and the involvement of these epigenetic modifications in the outcomes. Sixty normal-weight, overweight and obese women followed a 16-weeks weight reduction program. DNA methylation levels at different CpG sites of CLOCK, BMAL1 and PER2 genes were analyzed by Sequenom's MassARRAY in white blood cells obtained before the treatment. Statistical differences between normal-weight and overweight + obese subjects were found in the methylation status of different CpG sites of CLOCK (CpGs 1, 5-6, 8 and 11-14) and, with lower statistical significance, in BMAL1 (CpGs 6-7, 8, 15 and 16-17). The methylation pattern of different CpG sites of the three genes showed significant associations with anthropometric parameters such as body mass index and adiposity, and with a MetS score. Moreover, the baseline methylation levels of CLOCK CpG 1 and PER2 CpGs 2-3 and 25 correlated with the magnitude of weight loss. Interestingly, the percentage of methylation of CLOCK CpGs 1 and 8 showed associations with the intake of monounsaturated and polyunsaturated fatty acids. This study demonstrates for the first time an association between methylation status of CpG sites located in clock genes (CLOCK, BMAL1 and PER2) with obesity, MetS and weight loss. Moreover, the methylation status of different CpG sites in CLOCK and PER2 could be used as biomarkers of weight-loss success, particularly CLOCK CPGs 5-6

Psychoeducational preventive treatment for women at risk of postpartum depression: study protocol for a randomized controlled trial, PROGEA

Background: Postpartum depression is a disease with a prevalence of 20% that has deleterious consequences not only for the mother but also for the baby and can cause delays in physical, social and cognitive development. In this context, the European Union Committee on Public Health has declared it essential that preventative measures are taken by centres providing care for women with a multidisciplinary approach. PROGEA is a multicentre, single-blind randomized, 3-year, longitudinal clinical trial aiming to evaluate the efficacy of a psychoeducational programme in preventing postpartum depression in at-risk women, based on a range of clinical variables, and explore prognostic factors. This paper describes the methods and rationale behind the study. Methods: We will study women receiving treatment as usual plus a psychoeducation cognitive behavioural therapy (CBT)-based intervention and a control group receiving only treatment as usual. The sample will be recruited from an incidental sampling of pregnant women in two health regions. We will recruit 600 women in the third trimester of pregnancy who consent to take part in the study. Almost half of the women, about 280, would be expected to have some risk factors for postpartum depression. All those found to have risk factors will be evaluated, and we estimate that a quarter will be classified as at-risk of developing postpartum depression as measured with the Edinburgh Postnatal Depression Scale. This subset will be randomly allocated to receive treatment as usual with or without the CBT intervention. Six sessions of CBT (1 individual and 5 group) will be offered by a psychologist. Discussion: Findings from this study will be used to design a definitive study that will examine the clinical and cost-effectiveness of the CBT-based intervention in improving the mood of women in the postpartum period.This work was supported by local grants from the Department of Education, Linguistic Policy and Culture of the Basque Country Government (2011111110)

On the origin of correlated X-ray/VHE emission from LS I +61 303

The MAGIC collaboration has recently reported correlated X-ray and very high-energy gamma-ray emission from the gamma-ray binary LS I +61 303 during ~60% of one orbit. These observations suggest that the emission in these two bands has its origin in a single particle population. We aim at improving our understanding of the source behaviour by explaining the simultaneous X-ray and VHE data through a radiation model. We use a model based on a one zone population of relativistic leptonic particles assuming dominant adiabatic losses located at the position of the compact object. The adiabatic cooling timescale is inferred from the X-ray fluxes. The model can reproduce the spectra and lightcurves in the X-ray and VHE bands. Adiabatic losses could be the key ingredient to explain the X-ray and partially the VHE lightcurves. From the best fit result, we obtain a magnetic field of B=0.2 G, a minimum luminosity budget of ~2x10^35 erg/s and a relatively high acceleration efficiency. In addition, our results seem to confirm that the GeV emission detected by Fermi does not come from the same parent particle population as the X-ray and VHE emission and the Fermi spectrum poses a constraint on the hardness of the particle spectrum at lower energies. In the context of our scenario, more sensitive observations would allow to constrain the inclination angle, which could determine the nature of the compact object

Sox2 promotes tamoxifen resistance in breast cancer cells

Development of resistance to therapy continues to be a serious clinical problem in breast cancer management. Cancer stem/progenitor cells have been shown to play roles in resistance to chemo- and radiotherapy. Here, we examined their role in the development of resistance to the oestrogen receptor antagonist tamoxifen. Tamoxifen-resistant cells were enriched for stem/progenitors and expressed high levels of the stem cell marker Sox2. Silencing of the SOX2 gene reduced the size of the stem/progenitor cell population and restored sensitivity to tamoxifen. Conversely, ectopic expression of Sox2 reduced tamoxifen sensitivity in vitro and in vivo. Gene expression profiling revealed activation of the Wnt signalling pathway in Sox2-expressing cells, and inhibition of Wnt signalling sensitized resistant cells to tamoxifen. Examination of patient tumours indicated that Sox2 levels are higher in patients after endocrine therapy failure, and also in the primary tumours of these patients, compared to those of responders. Together, these results suggest that development of tamoxifen resistance is driven by Sox2-dependent activation of Wnt signalling in cancer stem/progenitor cells

A escola que teño, a escola que quero. Un achegamento ás prácticas educativas e ás necesidades nos CRA de Ourense

O estudo presentado forma parte dun proxecto financiado nunha convocatoria competitiva froito dunha colaboración entre a Deputación de Ourense e a Universidade de Vigo. O seu obxectivo é coñecer as necesidades educativas dos centros rurais agrupados (CRA) ourensáns orixinadas a partir da súa particular organización, así como estudar as barreiras e as fortalezas do ensino no rural desde a perspectiva dos axentes educativos (alumnado, familias e profesorado). Para darlles voz, a metodoloxía empregada foi de corte cualitativo, co uso de instrumentos e de ferramentas combinadas como as asembleas temáticas, fotovoz, ou debuxo-conversación e as frases incompletas. O tratamento dos datos apoiouse no software ATLAS.ti 22 empregando categorías emerxentes para analizar o contido. Os resultados amosan o mantemento da matrícula e a itinerancia do profesorado como unha das maiores barreiras ás que se enfrontan estas institucións. Pola contra, o medio rural e as relacións de proximidade entre toda a comunidade, que se producen grazas en gran medida ás contornas nas que se sitúan as escolas, preséntanse como as grandes fortalezas. Deste estudo despréndese unha forte necesidade de crer na prosperidade da escola rural como un espazo no que é posible combinar innovación e tradición a prol dunha aprendizaxe válida e de calidade

Early survival and growth plasticity of 33 species planted in 38 arboreta across the European Atlantic area

To anticipate European climate scenarios for the end of the century, we explored the climate gradient within the REINFFORCE (RÉseau INFrastructure de recherche pour le suivi et l’adaptation des FORêts au Changement climatiquE) arboreta network, established in 38 sites between latitudes 37 and 57 , where 33 tree species are represented. We aim to determine which climatic variables best explain their survival and growth, and identify those species that are more tolerant of climate variation and those of which the growth and survival future climate might constrain. We used empirical models to determine the best climatic predictor variables that explain tree survival and growth. Precipitation-transfer distance was most important for the survival of broadleaved species, whereas growing-season-degree days best explained conifer-tree survival. Growth (annual height increment) was mainly explained by a derived annual dryness index (ADI) for both conifers and broadleaved trees. Species that showed the greatest variation in survival and growth in response to climatic variation included Betula pendula Roth, Pinus elliottii Engelm., and Thuja plicata Donn ex D.Don, and those that were least affected included Quercus shumardii Buckland and Pinus nigra J.F.Arnold. We also demonstrated that provenance differences were significant for Pinus pinea L., Quercus robur L., and Ceratonia siliqua L. Here, we demonstrate the usefulness of infrastructures along a climatic gradient like REINFFORCE to determine major tendencies of tree species responding to climate changesinfo:eu-repo/semantics/publishedVersio