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131.
Guillermo A. Cecchi Lejian Huang Javeria Ali Hashmi Marwan Baliki María V. Centeno Irina Rish A. Vania Apkarian 《PLoS computational biology》2012,8(10)
While the static magnitude of thermal pain perception has been shown to follow a power-law function of the temperature, its dynamical features have been largely overlooked. Due to the slow temporal experience of pain, multiple studies now show that the time evolution of its magnitude can be captured with continuous online ratings. Here we use such ratings to model quantitatively the temporal dynamics of thermal pain perception. We show that a differential equation captures the details of the temporal evolution in pain ratings in individual subjects for different stimulus pattern complexities, and also demonstrates strong predictive power to infer pain ratings, including readouts based only on brain functional images. 相似文献
132.
Loidl A Claus R Ingolic E Deigner HP Hermetter A 《Biochimica et biophysica acta》2004,1690(2):150-158
Interaction of oxidized low-density lipoprotein (LDL) with arterial smooth muscle cells (SMC) is believed to play a key role in the development of atherosclerosis. Depending on the extent of oxidation, apolipoproteins and/or lipids in the particle may be modified and thus lead to different cellular responses (e.g. proliferation or cell death). Here we report on the signaling effects of LDL, in which only the lipids were oxidized. This so-called minimally modified LDL (mmLDL) mainly activated components involved in stress response and apoptotic cell death including p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase/stress-activated protein kinase (JNK) as well as neutral and acid sphingomyelinase. In contrast, proliferative signaling elements such as extracellular regulated kinase, AKT-kinase and phospho-BAD seem to play a minor role as they were only slightly stimulated by mmLDL. Ceramide, the hydrolysis product of sphingomyelin, seems to be a key mediator as it mimics mmLDL by inducing activation of the same signaling components. Moreover, mmLDL- and ceramide-associated effects on apoptotic protein kinases were abolished by NB6, a specific inhibitor of acid sphingomyelinase. Thus, acid sphingomyelinase is very likely to be primarily responsible for triggering intracellular signal transduction in SMC after exposure to mmLDL via formation of ceramide by an autocatalytic mechanism. 相似文献
133.
Sánchez-Soriano N Bottenberg W Fiala A Haessler U Kerassoviti A Knust E Löhr R Prokop A 《Developmental biology》2005,288(1):126-138
Dendrites represent arborising neurites in both vertebrates and invertebrates. However, in vertebrates, dendrites develop on neuronal cell bodies, whereas in higher invertebrates, they arise from very different neuronal structures, the primary neurites, which also form the axons. Is this anatomical difference paralleled by principal developmental and/or physiological differences? We address this question by focussing on one cellular model, motorneurons of Drosophila and characterise the compartmentalisation of these cells. We find that motorneuronal dendrites of Drosophila share with typical vertebrate dendrites that they lack presynaptic but harbour postsynaptic proteins, display calcium elevation upon excitation, have distinct cytoskeletal features, develop later than axons and are preceded by restricted localisation of Par6-complex proteins. Furthermore, we demonstrate in situ and culture that Drosophila dendrites can be shifted from the primary neurite to their soma, i.e. into vertebrate-like positions. Integrating these different lines of argumentation, we propose that dendrites in vertebrates and higher invertebrates have a common origin, and differences in dendrite location can be explained through translocation of neuronal cell bodies introduced during the evolutionary process by which arthropods and vertebrates diverged from a common urbilaterian ancestor. Implications of these findings for studies of dendrite development, neuronal polarity, transport and evolution are discussed. 相似文献
134.
Gailus-Durner V Fuchs H Becker L Bolle I Brielmeier M Calzada-Wack J Elvert R Ehrhardt N Dalke C Franz TJ Grundner-Culemann E Hammelbacher S Hölter SM Hölzlwimmer G Horsch M Javaheri A Kalaydjiev SV Klempt M Kling E Kunder S Lengger C Lisse T Mijalski T Naton B Pedersen V Prehn C Przemeck G Racz I Reinhard C Reitmeir P Schneider I Schrewe A Steinkamp R Zybill C Adamski J Beckers J Behrendt H Favor J Graw J Heldmaier G Höfler H Ivandic B Katus H Kirchhof P Klingenspor M Klopstock T Lengeling A 《Nature methods》2005,2(6):403-404
135.
BACKGROUND: Biochemical testing for pheochromocytoma by measurement of fractionated plasma metanephrines is limited by false positive rates of up to 18% in people without known genetic predisposition to the disease. The plasma normetanephrine fraction is responsible for most false positives and plasma normetanephrine increases with age. The objective of this study was to determine if we could improve the specificity of fractionated plasma measurements, by statistically adjusting for age. METHODS: An age-adjusted metanephrine score was derived using logistic regression from 343 subjects (including 33 people with pheochromocytoma) who underwent fractionated plasma metanephrine measurements as part of investigations for suspected pheochromocytoma at Mayo Clinic Rochester (derivation set). The performance of the age-adjusted score was validated in a dataset of 158 subjects (including patients 23 with pheochromocytoma) that underwent measurements of fractionated plasma metanephrines at Mayo Clinic the following year (validation dataset). None of the participants in the validation dataset had known genetic predisposition to pheochromocytoma. RESULTS: The sensitivity of the age-adjusted metanephrine score was the same as that of traditional interpretation of fractionated plasma metanephrine measurements, yielding a sensitivity of 100% (23/23, 95% confidence interval [CI] 85.7%, 100%). However, the false positive rate with traditional interpretation of fractionated plasma metanephrine measurements was 16.3% (22/135, 95% CI, 11.0%, 23.4%) and that of the age-adjusted score was significantly lower at 3.0% (4/135, 95% CI, 1.2%, 7.4%) (p < 0.001 using McNemar's test). CONCLUSION: An adjustment for age in the interpretation of results of fractionated plasma metanephrines may significantly decrease false positives when using this test to exclude sporadic pheochromocytoma. Such improvements in false positive rate may result in savings of expenditures related to confirmatory imaging. 相似文献
136.
137.
Sok‐Keng Tong Karen Mouriec Ming‐Wei Kuo Elisabeth Pellegrini Marie‐Madeleine Gueguen François Brion Olivier Kah Bon‐chu Chung 《Genesis (New York, N.Y. : 2000)》2009,47(2):67-73
Aromatase is an enzyme that catalyzes the synthesis of estrogen in gonads and brain. Teleost fish express aromatase (AroB) strongly in the brain facilitating its detailed examination. To understand the function of AroB in the brain, we generated transgenic zebrafish that expresses green fluorescent protein (GFP) driven by the brain aromatase cyp19a1b promoter. GFP was found in the radial glial cells of transgenic larvae and adult fish that overlap with AroB immunoreactivity in the correct temporal and spatial pattern. GFP was also coexpressed with radial cell marker BLBP, but was not in neurons. In addition, GFP expression in the radial glial cells was stimulated by estrogen, same as endogenous AroB expression. Thus, this transgenic line faithfully mimics the regulation of AroB expression in radial glial cells. It provides a powerful tool to further characterize progenitor radial cells in adult and developing fish and to evaluate estrogenic activities of xenoestrogens and phytoestrogens. genesis 47:67–73, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
138.
139.
Teija?AleniusEmail authorView authors OrcID profile Teemu?M?kk?nen Elisabeth?Holmqvist Antti?Ojala 《Vegetation History and Archaeobotany》2017,26(5):469-486
Two high-resolution pollen and charcoal analyses were constructed from sediments obtained from a small bay in eastern Finland in order to gain information on human activity during the Neolithic Stone Age, 5200–1800 bc. We used measurements of loss on ignition (LOI), magnetic susceptibility and geochemical analyses to describe the sedimentological characteristics. Palaeomagnetic dating and measurements of 137Cs-activity were supported by 14C-datings. The analyses revealed human activity between 4400 and 3200 bc, which is synchronous with archaeological cultures defined through different stages of Comb Ware pottery types and Middle Neolithic pottery types with asbestos as a primary temper. Direct evidence of Hordeum cultivation was dated to 4040–3930 cal bc. According to the pollen data, more significant effort was put into the production of fibres from hemp and lime than the actual cultivation of food. 相似文献
140.
QTL mapping of Fusarium head blight resistance in three related durum wheat populations 总被引:2,自引:0,他引:2
Noemie Prat Camille Guilbert Ursa Prah Elisabeth Wachter Barbara Steiner Thierry Langin Olivier Robert Hermann Buerstmayr 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(1):13-27