281 research outputs found
A gut-to-brain signal of fluid osmolarity controls thirst satiation.
Satiation is the process by which eating and drinking reduce appetite. For thirst, oropharyngeal cues have a critical role in driving satiation by reporting to the brain the volume of fluid that has been ingested1-12. By contrast, the mechanisms that relay the osmolarity of ingested fluids remain poorly understood. Here we show that the water and salt content of the gastrointestinal tract are precisely measured and then rapidly communicated to the brain to control drinking behaviour in mice. We demonstrate that this osmosensory signal is necessary and sufficient for satiation during normal drinking, involves the vagus nerve and is transmitted to key forebrain neurons that control thirst and vasopressin secretion. Using microendoscopic imaging, we show that individual neurons compute homeostatic need by integrating this gastrointestinal osmosensory information with oropharyngeal and blood-borne signals. These findings reveal how the fluid homeostasis system monitors the osmolarity of ingested fluids to dynamically control drinking behaviour
Human tribbles-1 controls proliferation and chemotaxis of smooth muscle cells via MAPK signaling pathways
Migration and proliferation of smooth muscle cells are key to a number of physiological and pathological processes, including wound healing and the narrowing of the vessel wall.Previous work has shown links between inflammatory stimuli and vascular smooth muscle cell proliferation and migration through mitogen activated protein kinase (MAPK) activation, though the molecular mechanisms of this process are poorly understood.
Here we report that tribbles-1, a recently described modulator of MAPK activation controls vascular smooth muscle cell proliferation and chemotaxis via the Jun Kinase pathway. Our findings demonstrate that this regulation takes place via direct interactions between tribbles-1 and MKK4/SEK1, a Jun activator kinase. The
activity of this kinase is dependent on tribbles-1 levels, whilst the activation and the expression of MKK4/SEK1 is not. In addition, tribbles-1 expression is elevated in
human atherosclerotic arteries compared to non-atherosclerotic controls, suggesting that this protein may pay a role in disease in vivo. In summary, the data presented here suggest an important regulatory role for trb-1 in vascular smooth muscle cell biology
Polymyalgia Rheumatica (PMR) Special Interest Group at OMERACT 11: outcomes of importance for patients with PMR
We worked toward developing a core outcome set for clinical research studies in polymyalgia rheumatica (PMR) by conducting (1) patient consultations using modified nominal group technique; (2) a systematic literature review of outcome measures in PMR; (3) a pilot observational study of patients presenting with untreated PMR, and further discussion with patient research partners; and (4) a qualitative focus group study of patients with PMR on the meaning of stiffness, using thematic analysis. (1) Consultations included 104 patients at 4 centers. Symptoms of PMR included pain, stiffness, fatigue, and sleep disturbance. Function, anxiety, and depression were also often mentioned. Participants expressed concerns about diagnostic delay, adverse effects of glucocorticoids, and fear of relapse. (2) In the systematic review, outcome measures previously used for PMR include pain visual analog scores (VAS), morning stiffness, blood markers, function, and quality of life; standardized effect sizes posttreatment were large. (3) Findings from the observational study indicated that asking about symptom severity at 7 AM, or "on waking," appeared more relevant to disease activity than asking about symptom severity "now" (which depended on the time of assessment). (4) Preliminary results were presented from the focus group qualitative study, encompassing broad themes of stiffness, pain, and the effect of PMR on patients' lives. It was concluded that further validation work is required before a core outcome set in PMR can be recommended. Nevertheless, the large standardized effect sizes suggest that pain VAS is likely to be satisfactory as a primary outcome measure for assessing response to initial therapy of PMR. Dissection of between-patient heterogeneity in the subsequent treatment course may require attention to comorbidity as a potential confounding factor
Effect of a Common Genetic Variant (p.V444A) in the Bile Salt Export Pump on the Inhibition of Bile Acid Transport by Cholestatic Medications
The bile salt export pump (BSEP) is the primary canalicular transporter responsible for the secretion of bile acids from hepatocytes into bile canaliculi, and inhibition of this transporter has been associated with drug-induced liver injury (DILI). A common variant (rs2287622; p.V444A) in the gene encoding BSEP has been associated with an increased risk of cholestatic DILI. Although p.444V BSEP (reference) and p.444A BSEP (variant) do not differ in their transport kinetics of taurocholic acid (TCA), transport of the more abundant glycocholic acid (GCA) has not been investigated. Importantly, differences in the susceptibility of p.444V and p.444A BSEP to inhibition by drugs causing cholestatic DILI have not been investigated. To address these issues, the transport kinetics of GCA were evaluated by incubating membrane vesicles expressing either p.444V or p.444A BSEP with GCA over a range of concentrations (1, 10, 25, 50, and 100 μM). The abilities of commonly used cholestatic medications to inhibit the transport of TCA and GCA by the reference and variant proteins were compared. Resulting data indicated that GCA transport kinetics for reference and variant BSEP followed Michaelis-Menten kinetics and were not statistically different [ Vmax values of 1132 ± 246 and 959 ± 256 pmol min-1 (mg of protein)-1, respectively, and Km values of 32.7 ± 18.2 and 45.7 ± 25.5 μM, respectively]. There were no statistically significant differences between the reference and variant BSEP in the inhibition of TCA or GCA transport by the cholestatic drugs tested. In conclusion, differential inhibition of TCA or GCA transport cannot account for an association between the variant BSEP and the risk for cholestatic DILI due to the drugs tested
Increased Serum and Musculotendinous Fibrogenic Proteins following Persistent Low-Grade Inflammation in a Rat Model of Long-Term Upper Extremity Overuse.
We examined the relationship between grip strength declines and muscle-tendon responses induced by long-term performance of a high-repetition, low-force (HRLF) reaching task in rats. We hypothesized that grip strength declines would correlate with inflammation, fibrosis and degradation in flexor digitorum muscles and tendons. Grip strength declined after training, and further in weeks 18 and 24, in reach limbs of HRLF rats. Flexor digitorum tissues of reach limbs showed low-grade increases in inflammatory cytokines: IL-1β after training and in week 18, IL-1α in week 18, TNF-α and IL-6 after training and in week 24, and IL-10 in week 24, with greater increases in tendons than muscles. Similar cytokine increases were detected in serum with HRLF: IL-1α and IL-10 in week 18, and TNF-α and IL-6 in week 24. Grip strength correlated inversely with IL-6 in muscles, tendons and serum, and TNF-α in muscles and serum. Four fibrogenic proteins, TGFB1, CTGF, PDGFab and PDGFbb, and hydroxyproline, a marker of collagen synthesis, increased in serum in HRLF weeks 18 or 24, concomitant with epitendon thickening, increased muscle and tendon TGFB1 and CTGF. A collagenolytic gelatinase, MMP2, increased by week 18 in serum, tendons and muscles of HRLF rats. Grip strength correlated inversely with TGFB1 in muscles, tendons and serum; with CTGF-immunoreactive fibroblasts in tendons; and with MMP2 in tendons and serum. Thus, motor declines correlated with low-grade systemic and musculotendinous inflammation throughout task performance, and increased fibrogenic and degradative proteins with prolonged task performance. Serum TNF-α, IL-6, TGFB1, CTGF and MMP2 may serve as serum biomarkers of work-related musculoskeletal disorders, although further studies in humans are needed
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The detection of bulk explosives using nuclear-based techniques
In 1986 we presented a rationale for the detection of bulk explosives based on nuclear techniques that addressed the requirements of civil aviation security in the airport environment. Since then, efforts have intensified to implement a system based on thermal neutron activation (TNA), with new work developing in fast neutron and energetic photon reactions. In this paper we will describe these techniques and present new results from laboratory and airport testing. Based on preliminary results, we contended in our earlier paper that nuclear-based techniques did provide sufficiently penetrating probes and distinguishable detectable reaction products to achieve the FAA operational goals; new data have supported this contention. The status of nuclear-based techniques for the detection of bulk explosives presently under investigation by the US Federal Aviation Administration (FAA) is reviewed. These include thermal neutron activation (TNA), fast neutron activation (FNA), the associated particle technique, nuclear resonance absorption, and photoneutron activation. The results of comprehensive airport testing of the TNA system performed during 1987-88 are summarized. From a technical point of view, nuclear-based techniques now represent the most comprehensive and feasible approach for meeting the operational criteria of detection, false alarms, and throughput. 9 refs., 5 figs., 2 tabs
Sustainable and Equitable Land Management Legal Framework, Planning Tools, Assessment
Spatial Planning, Land Use Planning, Land Management Instruments, Urban Land Management, Urban Planning, Cadastral Development, Sustainable Mobility Transition, Public Value Capture, Geoinformatics.This new volume of European Academy of Land Use and Development (EALD) contains broad view and interdisciplinary peer reviewed articles that inform the reader of most recent scientific investigations in Land Management. The spectrum of contributions cover: regulations, governance and implementation of land management along with assessment of relevant data.Some of the key highlights include various scientific and practical approaches, applied methods and systems together with a discussion and understanding of the government’s role in various European countries.Committed to sustainability, the articles entailed give evidence to Europe as an experimental ground for land management issues as well as allows for collaboration in pursuit of best practices.We support open access (free download), what about you
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