In this issue of Neuron, Chakrabarty et al. (2015) and Guillot-Sestier et al. (2015) reveal that the anti-inflammatory cytokine IL-10 inhibits Aβ clearance by microglia, worsening cognitive decline ...in mouse models of Alzheimer’s disease (AD). These studies provide further support that pro-inflammatory signaling is an innate immune defense mechanism in AD.
In this issue of Neuron, Chakrabarty et al. (2015) and Guillot-Sestier et al. (2015) reveal that the anti-inflammatory cytokine IL-10 inhibits Aβ clearance by microglia, worsening cognitive decline in mouse models of Alzheimer’s disease (AD). These studies provide further support that pro-inflammatory signaling is an innate immune defense mechanism in AD.
Frontier Livelihoods Turner, Sarah; Bonnin, Christine; Michaud, Jean
06/2015
eBook
Do ethnic minorities have the power to alter the course of their fortune when living within a socialist state? InFrontier Livelihoods, the authors focus their study on the Hmong - known in China as ...the Miao - in the Sino-Vietnamese borderlands, contending that individuals and households create livelihoods about which governments often know little.
The product of wide-ranging research over many years,Frontier Livelihoodsbridges the traditional divide between studies of China and peninsular Southeast Asia by examining the agency, dynamics, and resilience of livelihoods adopted by Hmong communities in Vietnam and in China's Yunnan Province. It covers the reactions to state modernization projects among this ethnic group in two separate national jurisdictions and contributes to a growing body of literature on cross-border relationships between ethnic minorities in the borderlands of China and its neighbors and in Southeast Asia more broadly.
Chemically functionalized or coated sensors are by far the most employed solution in gas sensing. However, their poor long term stability represents a concern in applications dealing with hazardous ...gases. Uncoated sensors are durable but their selectivity is poor or non-existent. In this study, multi-parametric discrimination is used as an alternative to selectivity for uncoated capacitive micromachined ultrasonic transducers (CMUTs). This paper shows how measuring simultaneously the attenuation coefficient and the time of flight under different nitrogen mixtures allows to identify hydrogen, carbon dioxide and methane from each other and determine their concentration along with identification of temperature and humidity drifts. Theoretical comparison and specific signal processing to deal with the issue of multiple reflections are also presented. Some potential applications are monitoring of refueling stations, vehicles and nuclear waste storage facilities.
Alzheimer’s disease (AD) is characterized by the accumulation of amyloid beta (Aβ) that is assumed to result from impaired elimination of this neurotoxic peptide. Most patients with AD also exhibit ...cerebral amyloid angiopathy, which consists of Aβ deposition within the cerebral vasculature. The contribution of monocytes in AD has so far been limited to macrophage precursors. In this study, we aimed to investigate whether circulating monocytes could play a role in the elimination of Aβ. With live intravital two-photon microscopy, we demonstrate that patrolling monocytes are attracted to and crawl onto the luminal walls of Aβ-positive veins, but not on Aβ-positive arteries or Aβ-free blood vessels. Additionally, we report the presence of crawling monocytes carrying Aβ in veins and their ability to circulate back into the bloodstream. Selective removal of Ly6Clo monocytes in APP/PS1 mice induced a significant increase of Aβ load in the cortex and hippocampus. These data uncover the ability of Ly6Clo monocytes to naturally target and eliminate Aβ within the lumen of veins and constitute a potential therapeutic target in AD.
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•Ly6Clo monocytes are attracted to and crawl selectively onto Aβ-positive veins•Monocytes take up Aβ and circulate back to the bloodstream•Aβ deposition and elimination by monocytes is dynamic in veins of young APP/PS1 mice•Ablation of Ly6Clo monocytes in APP/PS1 mice increases Aβ load
Alzheimer’s disease (AD) is characterized by the accumulation of neurotoxic amyloid beta (Aβ) within the brain parenchyma and cerebral vasculature. In this study, Rivest and colleagues demonstrate in mice that Ly6Clo patrolling monocytes migrate and crawl selectively onto Aβ-positive veins. These monocytes then take up vascular Aβ from the lumen and circulate back to the bloodstream. Importantly, their ablation increased Aβ levels in the brain. Together, these findings suggest a possible mechanism for the elimination of Aβ from the CNS.
The facilitation model of ecological succession was advanced by plant ecologists in the late 1970s and was then introduced to carrion ecology in the late 1980s, without empirical evidence of its ...applicability. Ecologists in both disciplines proposed removing early colonists, in this case fly eggs and larvae, from the substrate to determine whether other species could still colonize, which to our knowledge has never been attempted. Here, we tested the facilitation model in a carrion system by removing fly eggs and larvae from carcasses that were exposed in agricultural fields and assigned to one of the following treatment levels of removal intensity: 0, < 5, 50, and 100%. Subsequent patterns of colonisation did not provide support for the applicability of the facilitation model in carrion systems. Although results showed, in part, that the removal of fly eggs and larvae decreased the decomposition rate of carcasses, the removal did not prevent colonization by secondary colonizers. Finally, we discuss future studies and make recommendations as to how the facilitation model could be improved, firstly by being more specific about the scale where facilitation is believed to be occurring, secondly by clearly stating what environmental modification is believed to be involved, and thirdly by disentangling facilitation from priority effects.
Gas sensors are devices that can detect and/or discriminate gases in their surroundings. Some of these devices are based on vibrating structure covered with a coating sensitive to the species to ...detect. But such a layer can cause device failures issues like ageing, low reliability and high response time. Nonetheless, gas sensors are of importance for industrial environments in many applications. In addition, in some cases, the sensors must operate in harsh environments, that can lead to a severe degradation of the devices.
In this paper, we propose to review different MEMS devices, without any sensitive layer, for gas detection applications. The objective is to measure a physical property of the gas in order to determine its concentration. With the microsystem devices, limits of detection as low as 0.2 % has been obtained, illustrating the capabilities of the structures elaborated. And in our case, due to the absence of sensitive film that must be adapted according to the species to detect, it leads to generic sensors, compatible with many different gases. Moreover, by combining the measures of 2 physical parameters, the discrimination of the gases, with their respective concentrations, is accessible.
Alzheimer’s disease (AD) is the most common cause of dementia worldwide. The pathogenesis of this neurodegenerative disease, currently without curative treatment, is associated with the accumulation ...of amyloid β (Aβ) in brain parenchyma and cerebral vasculature. AD patients are unable to clear this toxic peptide, leading to Aβ accumulation in their brains and, presumably, the pathology associated with this devastating disease. Compounds that stimulate the immune system to clear Aβ may therefore have great therapeutic potential in AD patients. Monophosphoryl lipid A (MPL) is an LPS-derived Toll-like receptor 4 agonist that exhibits unique immunomodulatory properties at doses that are nonpyrogenic. We show here that repeated systemic injections of MPL, but not LPS, significantly improved AD-related pathology in APP ₛwₑ/PS1 mice. MPL treatment led to a significant reduction in Aβ load in the brain of these mice, as well as enhanced cognitive function. MPL induced a potent phagocytic response by microglia while triggering a moderate inflammatory reaction. Our data suggest that the Toll-like receptor 4 agonist MPL may be a treatment for AD.
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