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Mohand Mesbah Ilka Nemere Petros Papagerakis Jean-Raphael Nefussi Silvana Orestes-Cardoso Catherine Nessmann Ariane Berdal 《Journal of bone and mineral research》2002,17(9):1588-1596
The calciotropic hormone 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] has been established to control skeletal tissue formation and biomineralization via the regulation of gene expression. This action involves the well-characterized nuclear 1,25(OH)2D3 receptor. However, it has been recognized that several cellular responses to 1,25(OH)2D3 may not to be related to the exclusive nuclear receptor. Indeed, this secosteroid is able to generate rapid responses that have been proposed to be mediated by interactions of the ligand, which is a putative cell membrane-associated rapid-response steroid (MARRS) binding protein for 1,25(OH)2D3 [1,25D3-MARRS]. The nongenomic pathway of 1,25(OH)2D3 was studied here in detail by immunolocalization of the 1,25D3-MARRS during the specific context of human prenatal development. Western blotting with proteins extracted from 4 week- to 27-week-old embryos was performed, evidencing a 65-kDa molecular species recognized by antibody Ab 099 generated against synthetic peptides corresponding to the N terminus of the 1,25D3-MARRS from chick intestinal basolateral membranes. Based on this biochemical conservation of protein in the human species, the temporospatial expression patterns were established in the craniofacial skeleton at the same ages. Comparative analysis was performed in teeth and bones from early morphogenesis to terminal cell differentiation and extracellular biomineralization. The data show the potential implication of 1,25D3-MARRS in the heterogeneous cell population including ameloblasts, odontoblasts, osteoblasts, and osteoclasts. The epithelial-mesenchymal cascade related to odontogenesis was coincident with a sequence of up- and down-regulation of immunoreactive 1,25D3-MARRS. Biomineralization was associated with a striking up-regulation in the adjoining secretory cells in all tissues. Finally, osteoclasts appeared also to express the 1,25D3-MARRS during these early phases of bone modeling. Previously obtained data of the nuclear vitamin D receptor (VDR) expression and this study on 1,25D3-MARRS suggest the existence of cross-talk between the genomic and nongenomic pathways during human development. 相似文献
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Little is known about how the brain binds together signals from multiple sensory modalities to produce unified percepts of objects and events in the external world. Using event-related functional magnetic resonance imaging (fMRI) in humans, we measured transient brain responses to auditory/visual binding, as evidenced by a sound-induced change in visual motion perception. Identical auditory and visual stimuli were presented in all trials, but in some trials they were perceived to be bound together and in others they were perceived as unbound unimodal events. Cross-modal binding was associated with higher activity in multimodal areas, but lower activity in predominantly unimodal areas. This activation pattern suggests that a reciprocal and 'competitive' interaction between multimodal and unimodal areas underlies the perceptual interpretation of simultaneous signals from multiple sensory modalities. 相似文献
5.
Depolarization-induced retrograde synaptic inhibition in the mouse cerebellar cortex is mediated by 2-arachidonoylglycerol 总被引:3,自引:0,他引:3
Bela Szabo Michal J. Urbanski Tiziana Bisogno Vincenzo Di Marzo Aitziber Mendiguren Wolfram U. Baer Ilka Freiman 《The Journal of physiology》2006,577(1):263-280
Endocannabinoids acting on CB1 cannabinoid receptors are involved in short- and long-term depression of synaptic transmission. The aim of the present study was to determine which endocannabinoid, anandamide or 2-arachidonoylglycerol (2-AG), is involved in depolarization-induced suppression of inhibition (DSI) in the cerebellar cortex, which is the most widely studied form of short-term depression. Depolarization of Purkinje cells in the mouse cerebellum led to an increase in intracellular calcium concentration and to suppression of the inhibitory input to these neurons (i.e. DSI occurred). Orlistat and RHC80267, two blockers of sn -1-diacylglycerol lipase, the enzyme catalysing 2-AG formation, abolished DSI by acting downstream of calcium influx. In contrast, DSI occurred also in the presence of a phospholipase C inhibitor. Intact operation of the calcium-dependent messengers calmodulin and Ca2+ –calmodulin-dependent protein kinase II were necessary for DSI. DSI was potentiated by an inhibitor of the main 2-AG-degrading enzyme, monoacylglycerol lipase. Interference with the anandamide metabolizing enzyme, fatty acid amide hydrolase, did not modify DSI. Thus, three kinds of observations identified 2-AG as the endocannabinoid involved in DSI in the mouse cerebellum: DSI was abolished by diacylglycerol lipase inhibitors; DSI was potentiated by a monoglyceride lipase inhibitor; and DSI was not changed by an inhibitor of fatty acid amide hydrolase. Further experiments indicated that 2-AG is the endocannabinoid mediating short-term retrograde signalling also at other synapses: orlistat abolished DSI in the rat cerebellum, DSI in the mouse substantia nigra pars reticulata and depolarization-induced suppression of excitation in the mouse cerebellum. 相似文献
6.
Criscione JC Lorenzen-Schmidt I Humphrey JD Hunter WC 《Annals of biomedical engineering》1999,27(2):123-130
Finite extension and torsion tests on cardiac papillary muscles are presently the best way to directly measure the response to shear along myocardial fibers. Quantifying this response is necessary for determining the complete three-dimensional constitutive behavior of myocardium as a transversely isotropic material. Analysis of such tests is complicated, however, since papillary muscles are materially inhomogeneous, consisting of a myocardial core surrounded by an endocardial sheath that is rich in collagen. In this article, we show that the papillary muscle response to extension and torsion additively decouples into the response of the bare myocardial core plus the response of an endocardial sheath filled with fluid (assuming the muscle is a radially inhomogeneous and incompressible continuum with cylindrical symmetry). This result allows the endocardial response to be subtracted from the intact papillary muscle response to obtain the response of the bare myocardial core. An initial estimate suggests that the endocardial sheath affects the axial moment significantly (50% of torque for all twists at low stretch) but affects the axial force only slightly (<10% at moderate twists). © 1999 Biomedical Engineering Society.
PAC99: 8719Hh, 8719Rr, 8719Ff 相似文献
7.
Zheng B Cao KY Chan CP Choi JW Leung W Leung M Duan ZH Gao Y Wang M Di B Hollidt JM Bergmann A Lehmann M Renneberg I Tam JS Chan PK Cautherley GW Fuchs D Renneberg R 《Clinical immunology (Orlando, Fla.)》2005,116(1):18-26
Neopterin and C-reactive protein (CRP) concentrations were determined in serum samples from 129 severe acute respiratory syndrome (SARS) patients and 156 healthy blood donors. In the patients with confirmed SARS, an early neopterin elevation was detected already at the day of onset of symptoms and rose to a maximum level of 45.0 nmol/L 3 days after the onset. All SARS patients had elevated neopterin concentrations (>10 nmol/L) within 9 days after the onset. The mean neopterin concentrations were 34.2 nmol/L in acute sera of SARS patients, 5.1 nmol/L in convalescent sera, and 6.7 nmol/L in healthy controls. In contrast, the mean CRP concentrations in both acute and convalescent sera of SARS patients were in the normal range (<10 mg/L). Serum neopterin level in SARS patients was associated with fever period and thus the clinical progression of the disease, while there was no significant correlation between the CRP level and the fever period. Serum neopterin may allow early assessment of the severity of SARS. The decrease of neopterin level was found after steroid treatment, which indicates that blood samples should be collected before steroid treatment for the neopterin measurement. 相似文献
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Dominik N?rz Susanne Pfefferle Thomas Brehm Gefion Franke Ilka Grewe Birte Knobling Martin Aepfelbacher Samuel Huber Eva M. Klupp Sabine Jordan Marylyn M. Addo Julian Schulze zur Wiesch Stefan Schmiedel Marc Lütgehetmann Johannes K. Knobloch 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(26)
10.
Maria Alenita Oliveira Ana Luisa Godoy Fernandes Lucia Ande Santos Maria Amélia dos Santos Carvalho Sonia Maria Faresin Ilka Lopes Santoro 《The Journal of asthma》2013,50(5):407-410
Aim. To study any discriminative properties of SF-36 and QQL-EPM in stable and non-controlled moderate asthmatic patients. Methods. A total of 63 asthmatic patients were assessed regarding asthma symptoms, FEV1 % predicted value, PEF, ED visits and hospitalizations, QQL-EPM and SF-36 questionnaires. Results. QQL-EPM highlighted significance in all domains to distinguish stable from non-controlled patients (p = 0.0001) while SF-36 was only significant in 3 of its 7 domains (p = 0.009). Conclusion. The study showed that the specific quality of life questionnaire for asthma (QQL-EPM) demonstrates better discriminative properties that characterize asthma control when compared with the more generic SF-36 questionnaire. 相似文献