111 research outputs found

    TREM2 deficiency attenuates neuroinflammation and protects against neurodegeneration in a mouse model of tauopathy

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    Significance Alzheimer’s disease (AD) is the most common cause of dementia and is a major public health problem for which there is currently no disease-modifying treatment. There is an urgent need for greater understanding of the molecular mechanisms underlying neurodegeneration in patients to create better therapeutic options. Recently, genetic studies uncovered novel AD risk variants in the microglial receptor, triggering receptor expressed on myeloid cells 2 (TREM2). Previous studies suggested that loss of TREM2 function worsens amyloid-β (Aβ) plaque-related toxicity. In contrast, we observe TREM2 deficiency mitigates neuroinflammation and protects against brain atrophy in the context of tau pathology. These findings indicate dual roles for TREM2 and microglia in the context of amyloid versus tau pathology, which are important to consider for potential treatments targeting TREM2.</jats:p

    Satellite Tracking of Manta Rays Highlights Challenges to Their Conservation

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    We describe the real-time movements of the last of the marine mega-vertebrate taxa to be satellite tracked – the giant manta ray (or devil fish, Manta birostris), the world's largest ray at over 6 m disc width. Almost nothing is known about manta ray movements and their environmental preferences, making them one of the least understood of the marine mega-vertebrates. Red listed by the International Union for the Conservation of Nature as ‘Vulnerable’ to extinction, manta rays are known to be subject to direct and incidental capture and some populations are declining. Satellite-tracked manta rays associated with seasonal upwelling events and thermal fronts off the Yucatan peninsula, Mexico, and made short-range shuttling movements, foraging along and between them. The majority of locations were received from waters shallower than 50 m deep, representing thermally dynamic and productive waters. Manta rays remained in the Mexican Exclusive Economic Zone for the duration of tracking but only 12% of tracking locations were received from within Marine Protected Areas (MPAs). Our results on the spatio-temporal distribution of these enigmatic rays highlight opportunities and challenges to management efforts

    Complete Momentum Balance in Ionization of Hâ‚‚ by 75-keV-Proton Impact for Varying Projectile Coherence

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    We report on a kinematically complete experiment on ionization of H2 by proton impact. While a significant impact of the projectile coherence properties on the scattering-angle dependence of double-differential cross sections (DDCSs), reported earlier, is confirmed by the present data, only weak coherence effects are found in the electron and recoil-ion momentum dependence of the DDCSs. This suggests that the phase angle in the interference term is determined primarily by the projectile momentum transfer rather than by the recoil-ion momentum. We therefore cannot rule out the possibility that the interference observed in our data is not primarily due to a two-center effect

    Fully Differential Study of Interference Effects in the Ionization of Hâ‚‚ by Proton Impact

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    We have measured fully differential cross sections for ionization of H2 by 75-keV proton impact. The coherence length of the projectile beam was varied by changing the distance between a collimating slit and the target. By comparing the cross sections measured for large and small coherence lengths pronounced interference effects could be identified in the data. A surprising result is that the phase angle in the interference term is primarily determined by the momentum transfer and only to a lesser extent by the recoil-ion momentum

    Strong Lens Models for 37 Clusters of Galaxies from the SDSS Giant Arcs Survey

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    We present strong gravitational lensing models for 37 galaxy clusters from the SDSS Giant Arcs Survey. We combine data from multi-band Hubble Space Telescope WFC3imaging, with ground-based imaging and spectroscopy from Magellan, Gemini, APO, and MMT, in order to detect and spectroscopically confirm new multiply-lensed background sources behind the clusters. We report spectroscopic or photometric redshifts of sources in these fields, including cluster galaxies and background sources. Based on all available lensing evidence, we construct and present strong lensing mass models for these galaxy clusters.Comment: 53 pages; submitted to ApJ

    Evaluación del segundo curso de capacitación en desarrollo rural :documento preliminar

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    Constituye tema conocido el problema que representa el Sector Agropecuario, (considerado como conjunto) para cada país latinoamericano y para el continente, en general; así mismo el hecho de que contemplado tal problema como un "denominador común" afecta con diversa intensidad, pero en casi todos los casos de manera significativa, la marcha de cada país y el ritmo de su desarrollo socio-económico integral, en función de la distinta influencia individual que ejercen los diferentes elementos que lo conforman. Es por esto por lo que el presente documento se abstiene de insistir en la real importancia y de citar minuciosamente cifras que expresen cuantitativamente la magnitud e incidencia del citado problema,. Se ha preferido dar razonada prioridad a los aspectos conceptuales y cualitativos, así como a las causales que generan la política nacional adoptada para instalar y operar al Servicio de Extensión

    AAV-mediated expression of anti-tau scFvs decreases tau accumulation in a mouse model of tauopathy

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    Tauopathies are characterized by the progressive accumulation of hyperphosphorylated, aggregated forms of tau. Our laboratory has previously demonstrated that passive immunization with an anti-tau antibody, HJ8.5, decreased accumulation of pathological tau in a human P301S tau-expressing transgenic (P301S-tg) mouse model of frontotemporal dementia/tauopathy. To investigate whether the

    Prevalencia de trastorno por déficit de atención e hiperactividad en niños y niñas con retraso mental de bucaramanaga, Colombia

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    ResumenAntecedentes: En ni&ntilde;os y ni&ntilde;as con retraso mental (RM) son frecuentes los sintomas de desatenci&oacute;n, hiperactividad e impulsibilidad. Sin embargo, no se conoce la prevalencia&nbsp; de trastorno por d&eacute;ficit de atenci&oacute;n e hiperactividad (TDAH) en ni&ntilde;os y ni&ntilde;as con RM.[Mat&iacute;nes SJ, Remolina LM, Pic&oacute;n AA, G&oacute;mez LF, Campo Arias A. Prevalencia de trastorno por d&eacute;ficit de atenci&oacute;n e hiperactividad en ni&ntilde;os y ni&ntilde;as con retraso mental de bucaramanaga, Colombia. MedUNAB 2004; 7:157-60].Palbras clave: Trastorno por d&eacute;ficit de atenci&oacute;n e hiperactividad, prevalencia, retraso mental

    Murine roseolovirus does not accelerate amyloid-β pathology and human roseoloviruses are not over-represented in Alzheimer disease brains

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    BACKGROUND: The role of viral infection in Alzheimer Disease (AD) pathogenesis is an area of great interest in recent years. Several studies have suggested an association between the human roseoloviruses, HHV-6 and HHV-7, and AD. Amyloid-β (Aβ) plaques are a hallmark neuropathological finding of AD and were recently proposed to have an antimicrobial function in response to infection. Identifying a causative and mechanistic role of human roseoloviruses in AD has been confounded by limitations in performing in vivo studies. Recent -omics based approaches have demonstrated conflicting associations between human roseoloviruses and AD. Murine roseolovirus (MRV) is a natural murine pathogen that is highly-related to the human roseoloviruses, providing an opportunity to perform well-controlled studies of the impact of roseolovirus on Aβ deposition. METHODS: We utilized the 5XFAD mouse model to test whether MRV induces Aβ deposition in vivo. We also evaluated viral load and neuropathogenesis of MRV infection. To evaluate Aβ interaction with MRV, we performed electron microscopy. RNA-sequencing of a cohort of AD brains compared to control was used to investigate the association between human roseolovirus and AD. RESULTS: We found that 5XFAD mice were susceptible to MRV infection and developed neuroinflammation. Moreover, we demonstrated that Aβ interacts with viral particles in vitro and, subsequent to this interaction, can disrupt infection. Despite this, neither peripheral nor brain infection with MRV increased or accelerated Aβ plaque formation. Moreover, -omics based approaches have demonstrated conflicting associations between human roseoloviruses and AD. Our RNA-sequencing analysis of a cohort of AD brains compared to controls did not show an association between roseolovirus infection and AD. CONCLUSION: Although MRV does infect the brain and cause transient neuroinflammation, our data do not support a role for murine or human roseoloviruses in the development of Aβ plaque formation and AD
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