38 research outputs found

    Pathogenesis of cerebral malformations in human fetuses with meningomyelocele

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    <p>Abstract</p> <p>Background</p> <p>Fetal spina bifida aperta (SBA) is characterized by a spinal meningomyelocele (MMC) and associated with cerebral pathology, such as hydrocephalus and Chiari II malformation. In various animal models, it has been suggested that a loss of ventricular lining (neuroepithelial/ependymal denudation) may trigger cerebral pathology. In fetuses with MMC, little is known about neuroepithelial/ependymal denudation and the initiating pathological events.</p> <p>The objective of this study was to investigate whether neuroepithelial/ependymal denudation occurs in human fetuses and neonates with MMC, and if so, whether it is associated with the onset of hydrocephalus.</p> <p>Methods</p> <p>Seven fetuses and 1 neonate (16–40 week gestational age, GA) with MMC and 6 fetuses with normal cerebral development (22–41 week GA) were included in the study. Identification of fetal MMC and clinical surveillance of fetal head circumference and ventricular width was performed by ultrasound (US). After birth, MMC was confirmed by histology. We characterized hydrocephalus by increased head circumference in association with ventriculomegaly. The median time interval between fetal cerebral ultrasound and fixing tissue for histology was four days.</p> <p>Results</p> <p>At 16 weeks GA, we observed neuroepithelial/ependymal denudation in the aqueduct and telencephalon together with sub-cortical heterotopias in absence of hydrocephalus and/or Chiari II malformation. At 21–34 weeks GA, we observed concurrence of aqueductal neuroepithelial/ependymal denudation and progenitor cell loss with the Chiari II malformation, whereas hydrocephalus was absent. At 37–40 weeks GA, neuroepithelial/ependymal denudation coincided with Chiari II malformation and hydrocephalus. Sub-arachnoidal fibrosis at the convexity was absent in all fetuses but present in the neonate.</p> <p>Conclusion</p> <p>In fetal SBA, neuroepithelial/ependymal denudation in the telencephalon and the aqueduct can occur before Chiari II malformation and/or hydrocephalus. Since denuded areas cannot re-establish cell function, neuro-developmental consequences could induce permanent cerebral pathology.</p

    Genetic manipulation of LKB1 elicits lethal metastatic prostate cancer

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    Gene dosage is a key defining factor to understand cancer pathogenesis and progression, which requires the development of experimental models that aid better deconstruction of the disease. Here, we model an aggressive form of prostate cancer and show the unconventional association of LKB1 dosage to prostate tumorigenesis. Whereas loss of Lkbl alone in the murine prostate epithelium was inconsequential for tumorigenesis, its combination with an oncogenic insult, illustrated by Pten heterozygosity, elicited lethal metastatic prostate cancer. Despite the low frequency of LKB1 deletion in patients, this event was significantly enriched in lung metastasis. Modeling the role of LKB1 in cellular systems revealed that the residual activity retained in a reported kinase-dead form, LKB1(K781), was sufficient to hamper tumor aggressiveness and metastatic dissemination. Our data suggest that prostate cells can function normally with low activity of LKB1, whereas its complete absence influences prostate cancer pathogenesis and dissemination

    Ciencias de la BiologĂ­a y AgronomĂ­a

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    Este volumen I contiene 17 capĂ­tulos arbitrados que se ocupan de estos asuntos en TĂłpicos Selectos de Ciencias de la BiologĂ­a y AgronomĂ­a, elegidos de entre las contribuciones, reunimos algunos investigadores y estudiantes. Se presenta un Estudio Comparativo de los Recursos HidrolĂłgico-Forestales de la Microcuenca de la Laguna de Epatlan, Pue. (1993 a 2014); la SituaciĂłn Actual de la Mancha de Asfalto en MaĂ­z (Zea mays L.) en los Municipios de Jiquipilas y Ocozocoautla, Chiapas, MĂ©xico; las poblaciones sobresalientes de maĂ­z de la raza Zapalote Chico, en la RegiĂłn Istmeña de Oaxaca; Se indica el Ă­ndice de ĂĄrea foliar de cultivo de Chile Poblano mediante dos mĂ©todos en condiciones protegidas; Esquivel, UrzĂșa y RamĂ­rez exploran el efecto de la biofertilizaciĂłn con Azospirillum en el crecimiento y producciĂłn de Jitomate; esbozan su artĂ­culo sobre la determinaciĂłn del nivel de Heterosis en hĂ­bridos de MaĂ­z para la Comarca Lagunera; una investigaciĂłn sobre la estabilizaciĂłn de semilla de Solanum lycopersicum durante el almacenamiento y estimulaciĂłn de la germinaciĂłn; acotan sobre el CTAB como una nueva opciĂłn para la detecciĂłn de Huanglongbing en cĂ­tricos, plantean su evaluaciĂłn sobre el aluminio y cĂłmo afecta la vida de florero de Heliconia psittacorum; indican sobre el impacto del H-564C, como un hĂ­brido de maĂ­z con alta calidad de proteina para el trĂłpico hĂșmedo de MĂ©xico; presetan su investigaciĂłn sobre la producciĂłn de Piña Cayena Lisa y MD2 (Ananas comosus L.) en condiciones de Loma Bonita, en Oaxaca; acotan sobre el efecto de coberteras como control biolĂłgico por conservaciĂłn contra ĂĄfidos en Nogal Pecanero; esbozan sobre la caracterizaciĂłn de cuatro genotipos de Frijol Negro en MartĂ­nez de la Torre, Veracruz, MĂ©xico; presentan una caracterizaciĂłn hidroecolĂłgica de la microcuenca de Arroyo Prieto, YurirĂ­a, Gto., y alternativas para su restauraciĂłn ambiental; presentan su investigaciĂłn sobre el efecto del hongo Beauveria bassiana sobre solubilizaciĂłn de fosfatos y la disponibilidad de fĂłsforo en el suelo; plantean su investigaciĂłn sobre la GerminaciĂłn y regeneraciĂłn in vitro de Epidendrum falcatum LINDL; esbozan su artĂ­culo sobre genotipos de frijol negro y su tolerancia a sequĂ­a terminal en Veracruz, MĂ©xico

    Envejecimiento de la poblaciĂłn

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    &bull;Actividades b&aacute;sicas de la vida diaria en personas mayores y factores asociados &bull;Asociaci&oacute;n entre depresi&oacute;n y posesi&oacute;n de mascotas en personas mayores &bull;Calidad de vida en adultos mayores de Santiago aplicando el instrumento WHOQOL-BREF &bull;Calidad de vida en usuarios con enfermedad de Parkinson, demencia y sus cuidadores, comuna de Vitacura &bull;Caracterizaci&oacute;n de egresos hospitalarios de adultos mayores en Puerto Natales (2007-2009) &bull;Comportamiento de las patolog&iacute;as incluidas como GES para el adulto mayor atendido en un Cesfam &bull;Contribuci&oacute;n de vitaminas y minerales a las ingestas recomendadas diarias en ancianos institucionalizados de Madrid &bull;Estado de salud oral del paciente inscrito en el Programa de Visita Domiciliaria &bull;Evaluaci&oacute;n del programa de discapacidad severa en Casablanca con la matriz de marco l&oacute;gico &bull;Factores asociados a satisfacci&oacute;n vital en una cohorte de adultos mayores de Santiago, Chile &bull;Pauta instrumental para la identificaci&oacute;n de riesgos para el adulto mayor autovalente, en su vivienda &bull;Perfil farmacol&oacute;gico del paciente geri&aacute;trico institucionalizado y posibles consecuencias en el deterioro cognitivo &bull;Programa de cuidados paliativos y alivio del dolor en Puerto Natales &bull;Rehabilitaci&oacute;n mandibular implantoprot&eacute;sica: efecto en calidad de vida relacionada con salud bucal en adultos mayores &bull;Salud bucodental en adultos mayores autovalentes de la Regi&oacute;n de Valpara&iacute;so &bull;Transici&oacute;n epidemiol&oacute;gica y el estudio de carga de enfermedad en Brasi

    Global maps of soil temperature

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    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world\u27s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Soy Niña

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    Este libro pretende contribuir al reencuentro de la educaciĂłn con esas finalidades que verdaderamente importan a una niña o un niño: ser feliz, jugar, vivir juntos y (no) aprender. Para ello hemos puesto el arte, nuestras experiencias y el saber acumulado al servicio del disfrute, el cuestionamiento, el anĂĄlisis crĂ­tico y la construcciĂłn comĂșn de un presente deseable. Un texto colaborativo coordinado por Ignacio CalderĂłn Almendros y realizado por alumnado de EducaciĂłn y Cambio Social en el Grado en EducaciĂłn Infantil de la Universidad de MĂĄlaga

    A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

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    The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Understanding how the subcommissural organ and other periventricular secretory structures contribute via the cerebrospinal fluid to neurogenesis

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    The dynamic and molecular composition of the cerebrospinal fluid (CSF) and, consequently, the CSF physiology is much more complex and fascinating than the simplistic view held for decades. Signal molecules either transported from blood to CSF or secreted into the CSF by circumventricular organs and CSF-contacting neurons, use the CSF to reach their targets in the brain, including the pre- and postnatal neurogenic niche. The subcommissural organ (SCO), a highly conserved brain gland present throughout the vertebrate phylum, is one of the sources for signals, as well as the choroid plexus, tanycytes and CSF-contacting neurons. The SCO secretes into the fetal and adult cerebrospinal fluid SCO-spondin, transthyretin and basic fibroblast growth factor. These proteins participate in certain aspects of neurogenesis, such as cell cycle of neural stem cells, neuronal differentiation and axon pathfinding. Through the cerebrospinal fluid, the SCO-secretory proteins may reach virtually any target in the embryonic and adult central nervous system. Since the SCO continues to secrete throughout life span, it seems likely that the neurogenetic property of the SCO compounds would be targeted to the niches where neurogenesis continues in adulthood. This review is aimed to bring into discussion early and new evidence concerning the role(s) of the SCO, and the probable mechanisms by which SCO compounds can readily reach the neurogenic niche of the subventricular zone flowing with the CSF to participate in the regulation of the neurogenic niche. As we unfold the multiples trans-fluid talks between discrete brain domains we will have more tools to influence such talks
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