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le Roux Aliza Mathibane Nthabiseng Nowak Katarzyna 《International journal of primatology》2019,40(6):661-670
International Journal of Primatology - Research suggests that wild animals in urban areas exhibit heightened behavioral flexibility when they encounter novel human-made objects, but most such... 相似文献
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Lorraine Pawson Norma B. Slepecky Stanley J. Bolanowski 《Somatosensory & motor research》2013,30(2):159-170
Light- and electron-microscopic immunocytochemistry (ICC) was performed on Pacinian corpuscles (PCs) obtained from cat mesentery to determine the presence and location of various proteins within the accessory capsule and the neurite. Antibodies to tubulin, neurofilament 200, actin, collagen II and V, glial fibrillary acidic protein (GFAP) and S-100 were used. Type II collagen was localized only in the outer core of the accessory capsule, which is composed of an inner core, an intermediate layer or growth zone, an outer core and an external capsule. Type V collagen was found only in the intermediate growth zone. Intermediate filaments labeled with anti-GFAP were only found in the inner core. The calcium-binding protein that was labeled by anti-S-100 was found only in the inner core. Diffuse and variable staining for actin is present throughout the accessory capsule. The differences in distribution of these various proteins within the capsule suggest different structural/functional properties of the various capsule regions. The neurite was found to contain microtubules (i.e., tubulin) and neurofilaments throughout, but these cellular inclusions were not found within the cytoplasmic extensions (filopodia) that project from the neurite into the hemilamellar clefts formed by the inner-core hemilamellae. The extensions, however, were found to contain actin in a much greater density than that seen in the neurite proper. The presence of actin, but apparent lack of other cytostructural elements within the extensions, is highly reminiscent of the composition of stereocilia found on vestibular and auditory hair cells. Since stereocilia have been shown to play a role in hair-cell mechanotransduction, it is possible that the cytoplasmic extensions are significantly involved with mechanotransduction within the PC. 相似文献
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Victoria A. Acosta-Rodríguez Sebastián Márquez Gabriela A. Salvador Susana J. Pasquaré Lucas D. Gorné Eduardo Garbarino-Pico Norma M. Giusto Mario Eduardo Guido 《Journal of lipid research》2013,54(7):1798-1811
Circadian clocks regulate the temporal organization of several biochemical processes, including lipid metabolism, and their disruption leads to severe metabolic disorders. Immortalized cell lines acting as circadian clocks display daily variations in [32P]phospholipid labeling; however, the regulation of glycerophospholipid (GPL) synthesis by internal clocks remains unknown. Here we found that arrested NIH 3T3 cells synchronized with a 2 h-serum shock exhibited temporal oscillations in a) the labeling of total [3H] GPLs, with lowest levels around 28 and 56 h, and b) the activity of GPL-synthesizing and GPL-remodeling enzymes, such as phosphatidate phosphohydrolase 1 (PAP-1) and lysophospholipid acyltransferases (LPLAT), respectively, with antiphase profiles. In addition, we investigated the temporal regulation of phosphatidylcholine (PC) biosynthesis. PC is mainly synthesized through the Kennedy pathway with choline kinase (ChoK) and CTP:phosphocholine cytidylyltranferase (CCT) as key regulatory enzymes. We observed that the PC labeling exhibited daily changes, with the lowest levels every ∼28 h, that were accompanied by brief increases in CCT activity and the oscillation in ChoK mRNA expression and activity. Results demonstrate that the metabolisms of GPLs and particularly of PC in synchronized fibroblasts are subject to a complex temporal control involving concerted changes in the expression and/or activities of specific synthesizing enzymes. 相似文献
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