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High-fidelity multimode fibre-based endoscopy for deep brain in vivo imaging

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Light(Science & Applications) 2018年第1期7卷 193-200页

作者： Sergey Turtaev Ivo T.Leite Tristan Altwegg-Boussac janelle M.P.Pakan Nathalie L.rochefort Tomáš Čižmár Leibniz Institute of Photonic Technology Albert-Einstein-Straße 9Jena 07745Germany School of Life Sciences University of DundeeNethergateDundee DD14HNUK School of Science and Engineering University of DundeeNethergateDundee DD14HNUK Centre for Discovery Brain Sciences University of EdinburghHugh Robson Building 15George SquareEdinburgh EH89XDUK Center for Behavioral Brain Sciences Institute of Cognitive Neurology and Dementia ResearchGerman Center for Neurodegenerative DiseasesLeipziger Straße 44Haus 64Magdeburg 39120Germany Simons Initiative for the Developing Brain University of EdinburghEdinburgh EH89XDUK Institute of Scientific Instruments of CAS Kralovopolska 147Brno 61264Czech Republic

Progress in neuroscience relies on new techniques for investigating the complex dynamics of neuronal *** ongoing challenge is to achieve minimally invasive and high-resolution observations of neuronal activity in vivo inside deep brain *** introduced methods for holographic control of light propagation in complex media enable the use of a hair-thin multimode optical fibre as an ultranarrow imaging *** to endoscopes based on graded-index lenses or fibre bundles,this new approach offers a footprint reduction exceeding an order of magnitude,combined with a significant enhancement in *** designed a compact and high-speed system for fluorescent imaging at the tip of a fibre,achieving a resolution of 1.18±0.04μm across a 50-μm field of view,yielding 7-kilopixel images at a rate of 3.5 frames/***,we demonstrate in vivo observations of cell bodies and processes of inhibitory neurons within deep layers of the visual cortex and hippocampus of anaesthetised *** study paves the way for modern microscopy to be applied deep inside tissues of living animal models while exerting a minimal impact on their structural and functional properties.

关键词： multimode fibre vivo

Climate Change Effect on Winter Temperature and Precipitation of Yellowknife, Northwest Territories, Canada from 1943 to 2011

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American Journal of Climate Change 2013年第4期2卷 275-283页

作者： janelle Laing Jacqueline Binyamin Department of Geography University of Winnipeg Winnipeg Canada

The correlation of the Southern Oscillation Index (SOI), Pacific Decadal Oscillation (PDO), Pacific North American Oscillation (PNA), Arctic Oscillation (AO), and Scandinavia (SCAND) indices with winter (DJF) temperature and precipitation for the period of 1943 to 2011 was analyzed to study climate change and variability of Yellowknife, NWT. SOI correlated negatively with both temperature (r = -0.14) and precipitation (r = -0.06) causing colder, drier conditions during La Nina and warmer, wetter conditions during El Nino. PDO was shown to have a strong positive correlation with both temperature (r = 0.60) and precipitation (r = 0.33) causing warmer, wetter weather in the positive phase and colder, drier weather in the negative phase. PNA showed the strongest positive correlation for both temperature (r = 0.69) and precipitation (r = 0.37) causing very warm and wet conditions in the positive phase and very cold and dry conditions during the negative phase. AO correlated negatively with temperature (r = -0.04) and positively with precipitation (r = 0.24) causing colder, wetter conditions in the positive phase and warmer, drier conditions in the negative phase. Finally SCAND was shown to have a weak negative correlation with both temperature (r = -0.10) and precipitation (r = -0.18). Sunspot area showed a strong negative correlation (r = -0.30) with temperature and a very weak positive correlation (r = 0.07) with total annual precipitation. Yellowknife’s average annual temperature and precipitation has increased by 2.5°C and 120 mm, respectively throughout the past 69 years.

关键词： Yellowknife Climate Change Climate Variability Climate Modes Teleconnections ENSO SOI PDO PNA AO SCAND Sunspot Area

Speckle Tracking Echocardiography Identifies Impaired Longitudinal Strain as a Common Deficit in Various Cardiac Diseases

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Cardiovascular Innovations and Applications 2018年第B7期3卷 237-250页

作者： randy r.Jeffrey robert F.Hamburger janelle Gooden-Ebanks John W.Petersen Division of Cardiovascular Medicine University of FloridaGainesvilleFLUSA

The use of speckle-tracking echocardiography(STE)is becoming an increasingly useful tool in the evaluation of myocardial *** software can track the motion of the specular pattern created by the interference of ultrasound with the myofibers of the heart and provide a quantitative means to evaluate subtle changes in ventricular function that often occur before changes in ventricular ejection fraction are *** is most often used to measure the change in shape(strain)of myocardial segments in the circumferential,radial,and longitudinal *** various diseases,including coronary artery disease,aortic stenosis,and mitral regurgitation,deficits in longitudinal strain appear to occur earlier than deficits in other measures of strain or in ejection *** of STE measures of left ventricular contraction has the potential to significantly affect clinical management and outcomes of ischemic and valvular heart disease given the ability to separate those with asymptomatic disease who may benefit from earlier interventions than current guidelines may suggest.

关键词： speckle tracking echocardiography longitudinal strain valvular heart disease,ischemic heart disease echocardiographic imaging

Nicotine-induced adrenal beta-arrestin1 upregulation mediates tobacco-related hyperaldosteronism leading to cardiac dysfunction

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World Journal of Cardiology 2020年第5期12卷 192-202页

作者： Natalie Cora Jennifer Ghandour Celina Marie Pollard Victoria Lynn Desimine Krysten Elaine Ferraino janelle Marie Pereyra rachel Valiente Anastasios Lymperopoulos Laboratory for the Study of Neurohormonal Control of the Circulation Department of Pharmaceutical Sciences(Pharmacology)College of PharmacyNova Southeastern UniversityFort LauderdaleFL 33328-2018United States

BACKGrOUND Tobacco-related products,containing the highly addictive nicotine together with numerous other harmful toxicants and carcinogens,have been clearly associated with coronary artery disease,heart failure,stroke,and other heart *** the mechanisms by which nicotine contributes to heart disease is elevation of the renin-angiotensin-aldosterone system(rAAS)***,and its major metabolite in humans cotinine,have been reported to induce rAAS activation,resulting in aldosterone elevation in *** has various direct and indirect adverse cardiac *** is produced by the adrenal cortex in response to angiotensin II(AngII)activating AngII type 1 *** activity increases in chronic smokers,causing raised aldosterone levels(nicotine exposure causes the same in rats).AngII receptors exert their cellular effects via either G proteins or the twoβarrestins(βarrestin1 and-2).AIM Since adrenal?arrestin1 is essential for adrenal aldosterone production and nicotine/cotinine elevate circulating aldosterone levels in humans,we hypothesized that nicotine activates adrenal?arrestin1,which contributes to rAAS activation and heart disease *** We studied human adrenocortical zona glomerulosa H295r cells and found that nicotine and cotinine upregulateβarrestin1 mrNA and protein levels,thereby enhancing AngII-dependent aldosterone synthesis and *** In contrast,sirNA-mediatedβarrestin1 knockdown reversed the effects of nicotine on AngII-induced aldosterone production in H295 r ***,nicotine promotes hyperaldosteronism via adrenalβarrestin1,thereby precipitating cardiac dysfunction,also in vivo,since nicotine-exposed experimental rats with adrenal-specificβarrestin1 knockdown display lower circulating aldosterone levels and better cardiac function than nicotine-exposed control animals with normal adrenalβarrestin1 *** Adrenalβarrestin1 upregulation is one of the mechanisms by whic

关键词： Adrenocortical zona glomerulosa cell Aldosterone βarrestin Nicotine Signal transduction Tobacco-related heart disease