131 research outputs found

    THE IMPACT OF GOVERNMENT POLICIES ON AGRICULTURAL PRODUCTIVITY AND STRUCTURE: PRELIMINARY RESULTS

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    Our paper begins with a consideration of the causal relationships among productivity, farm structure, government farm payments and public investments in research and extension. We then empirically test key relationships for a relatively recent period (1960-96) in the history of agricultural structural adjustment using a simultaneous equations econometric model. Future work will expand and refine the measurement of variables thought to explain the relationship between productivity and structure.Agricultural and Food Policy, Productivity Analysis,

    Redundant Gs-coupled serotonin receptors regulate amyloid-β metabolism in vivo

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    BACKGROUND: The aggregation of amyloid-β (Aβ) into insoluble plaques is a hallmark pathology of Alzheimer’s disease (AD). Previous work has shown increasing serotonin levels with selective serotonin re-uptake inhibitor (SSRI) compounds reduces Aβ in the brain interstitial fluid (ISF) in a mouse model of AD and in the cerebrospinal fluid of humans. We investigated which serotonin receptor (5-HTR) subtypes and downstream effectors were responsible for this reduction. RESULTS: Agonists of 5-HT(4)R, 5-HT(6)R, and 5-HT(7)R significantly reduced ISF Aβ, but agonists of other receptor subtypes did not. Additionally, inhibition of Protein Kinase A (PKA) blocked the effects of citalopram, an SSRI, on ISF Aβ levels. Serotonin signaling does not appear to change gene expression to reduce Aβ levels in acute timeframes, but likely acts within the cytoplasm to increase α-secretase enzymatic activity. Broad pharmacological inhibition of putative α-secretases increased ISF Aβ and blocked the effects of citalopram. CONCLUSIONS: In total, these studies map the major signaling components linking serotonin receptors to suppression of brain ISF Aβ. These results suggest the reduction in ISF Aβ is mediated by a select group of 5-HTRs and open future avenues for targeted therapy of AD. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13024-016-0112-5) contains supplementary material, which is available to authorized users

    Assessing Dietary Outcomes in Intervention Studies: Pitfalls, Strategies, and Research Needs.

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    To inform strategies to improve the dietary intakes of populations, robust evaluations of interventions are required. This paper is drawn from a workshop held at the International Society of Behavioral Nutrition and Physical Activity 2017 Annual Meeting, and highlights considerations and research priorities relevant to measuring dietary outcomes within intervention studies. Self-reported dietary data are typically relied upon in such studies, and it is recognized that these data are affected by random and systematic error. Additionally, differential error between intervention and comparison groups or pre- and post-intervention can be elicited by the intervention itself, for example, by creating greater awareness of eating or drinking occasions or the desire to appear compliant. Differential reporting can render the results of trials incorrect or inconclusive by leading to biased estimates and reduced statistical power. The development of strategies to address intervention-related biases requires developing a better understanding of the situations and population groups in which interventions are likely to elicit differential reporting and the extent of the bias. Also needed are efforts to expand the feasibility and applications of biomarkers to address intervention-related biases. In the meantime, researchers are encouraged to consider the potential for differential biases in dietary reporting in a given study, to choose tools carefully and take steps to minimize and/or measure factors such as social desirability biases that might contribute to differential reporting, and to consider the implications of differential reporting for study results

    Combination anti-Aβ treatment maximizes cognitive recovery and rebalances mTOR signaling in APP mice

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    Drug development for Alzheimer\u27s disease has endeavored to lower amyloid β (Aβ) by either blocking production or promoting clearance. The benefit of combining these approaches has been examined in mouse models and shown to improve pathological measures of disease over single treatment; however, the impact on cellular and cognitive functions affected by Aβ has not been tested. We used a controllable APP transgenic mouse model to test whether combining genetic suppression of Aβ production with passive anti-Aβ immunization improved functional outcomes over either treatment alone. Compared with behavior before treatment, arresting further Aβ production (but not passive immunization) was sufficient to stop further decline in spatial learning, working memory, and associative memory, whereas combination treatment reversed each of these impairments. Cognitive improvement coincided with resolution of neuritic dystrophy, restoration of synaptic density surrounding deposits, and reduction of hyperactive mammalian target of rapamycin signaling. Computational modeling corroborated by in vivo microdialysis pointed to the reduction of soluble/exchangeable Aβ as the primary driver of cognitive recovery

    Rapid in vivo measurement of B-amyloid reveals biphasic clearance kinetics in an Alzheimer\u27s mouse model

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    Accumulation of ?-amyloid peptide is a key step in Alzheimer?s disease pathogenesis. Yuede et al. propose a novel method to track ?-amyloid levels in vivo

    Characterization of the Prokaryotic Sodium Channel NavSp Pore with a Microfluidic Bilayer Platform

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    This paper describes the use of a newly-developed micro-chip bilayer platform to examine the electrophysiological properties of the prokaryotic voltage-gated sodium channel pore (NavSp) from Silicibacter pomeroyi. The platform allows up to 6 bilayers to be analysed simultaneously. Proteoliposomes were incorporated into suspended lipid bilayers formed within the microfluidic bilayer chips. The chips provide access to bilayers from either side, enabling the fast and controlled titration of compounds. Dose-dependent modulation of the opening probability by the channel blocking drug nifedipine was measured and its IC50 determined

    Recommending video content for use in group-based reminiscence therapy

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    REMPAD is a semi-automated cloud-based system used to facilitate digital reminiscence therapy for patients with mild-to-moderate dementia, enacted in a group setting. REMPAD uses profiles for participants and groups to proactively recommend interactive video content from the Internet to match these profiles. In this chapter, we focus on the design of the system and then the system architecture, the system build, data curation, and usage scenarios. We also report a series of steps carried out as part of our user-centered design approach to system development, and a series of analyses on interaction logs which indicate various levels of effectiveness for different configurations of the recommendation algorithm we use. The results indicate high user satisfaction when using the system, and strong tendency towards repeated use in future

    IL-27 Induced by Select Candida spp. via TLR7/NOD2 Signaling and IFN-β Production Inhibits Fungal Clearance

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    Candida spp. elicit cytokine production downstream of various pathogen recognition receptors (PRRs) including C-type lectin-like receptors (CLRs), Toll-like receptors (TLRs) and nucleotide oligomerisation domain (NOD)-like receptors (NLRs). IL-12 family members, IL-12p70 and IL-23, are important for host immunity against Candida spp. Herein we show that IL-27, another IL-12 family member, is produced by myeloid cells in response to select Candida spp. We demonstrate a novel mechanism for C. parapsilosis-mediated induction of IL-27 in a TLR7-, MyD88- and NOD2-dependent manner. Our data revealed that IFN-β is induced by C. parapsilosis, which in turn signals through the interferon-α/β receptor (IFNAR) and STAT1/2 to induce IL-27. Moreover, IL 27R (WSX-1) deficient mice systemically infected with C. parapsilosis displayed enhanced pathogen clearance compared to WT mice. This was associated with increased levels of pro-inflammatory cytokines in the serum and increased IFN-γ and IL-17 responses in the spleens of IL-27R deficient mice. Thus our data define a novel link between C. parapsilosis, TLR7, NOD2, IFN-β and IL-27 and we have identified an important role for IL-27 in the immune response against C. parapsilosis. Overall these findings demonstrate an important mechanism for the suppression of protective immune responses during infection with C. parapsilosis, which has potential relevance for infections with other fungal pathogens

    Improving the reach of vaccines to low-resource regions, with a needle-free vaccine delivery device and long-term thermostabilization

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    Dry-coated microprojections can deliver vaccine to abundant antigen-presenting cells in the skin and induce efficient immune responses and the dry-coated vaccines are expected to be thermostable at elevated temperatures. In this paper, we show that we have dramatically improved our previously reported gas-jet drying coating method and greatly increased the delivery efficiency of coating from patch to skin to from 6.5% to 32.5%, by both varying the coating parameters and removing the patch edge. Combined with our previous dose sparing report of influenza vaccine delivery in a mouse model, the results show that we now achieve equivalent protective immune responses as intramuscular injection (with the needle and syringe), but with only 1/30th of the actual dose. We also show that influenza vaccine coated microprojection patches are stable for at least 6 months at 23 degrees C. inducing comparable immunogenicity with freshly coated patches. The dry-coated microprojection patches thus have key and unique attributes in ultimately meeting the medical need in certain low-resource regions with low vaccine affordability and difficulty in maintaining "cold-chain" for vaccine storage and transport. (C) 2011 Elsevier B.V. All rights reserved

    Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

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    Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy
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