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861.
Michele Siqueira Daniel Francis Diego Gisbert Flávia Carvalho Alcantara Gomes Joice Stipursky 《Molecular neurobiology》2018,55(5):3660-3675
Neuroangiogenesis in the developing central nervous system is controlled by interactions between endothelial cells (ECs) and radial glia (RG) neural stem cells, although RG-derived molecules implicated in these events are not fully known. Here, we investigated the role of RG-secreted TGF-β1, in angiogenesis in the developing cerebral cortex. By isolation of murine microcapillary brain endothelial cells (MBECs), we demonstrate that conditioned medium from RG cultures (RG-CM) promoted MBEC migration and formation of vessel-like structures in vitro, in a TGF-β1-dependent manner. These events were followed by endothelial regulation of GPR124 and BAI-1 gene expression by RG-CM. Proteome profile of RG-CM identified angiogenesis-related molecules IGFBP2/3, osteopontin, endostatin, SDF1, fractalkine, TIMP1/4, Ang-1, pentraxin3, and Cyr61, some of them modulated by TGF-β1 induction. In vivo gain and loss of function assays targeting RG cells demonstrates a specific TGF-β1-dependent control of blood vessels branching in the cerebral cortex. Together, our results point to TGF-β1 signaling pathway as a potential mediator of the RG-EC interactions and shed light to the key role of RG in paving the brain vascular network. 相似文献
862.
Chaves Ana Luisa Arantes Carvalho Pedro Henrique Mendes Ferreira Marco Tulio Mendes Benites Flávio Rodrigo Gandolfi Techio Vânia Helena 《Protoplasma》2022,259(4):999-1011
Protoplasma - Polyploidy is the main mechanism for chromosome number variation in Cynodon. Taxonomic boundaries are difficult to define and, although phylogenetic studies indicate that some species... 相似文献
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Mysella charcoti is an Antarctic lasaeid bivalve and the most frequently encountered mollusc in Admiralty Bay, King George Island, South Shetlands. The behaviour of the species in aquaria, combined with analyses of the gross and microscopic morphologies and functioning of the organs in the mantle cavity of living and preserved specimens have allowed an understanding of important aspects of its biology. The role of the foot and its ciliature during the processes of dislodgement and burrowing within the sediment are described. The species is a free-living, shallow-burrower, with a predominantly deposit-feeding habit and derives part of its food from the labile settled organic deposits carried into the mantle cavity by the anterior–posterior current of water. Pedal sweep-feeding was not detected. M. charcoti is the first known lasaeid with ctenidia formed of the descending lamellae of the inner demibranchs only, a feature probably related to its highly specialised brooding habit. 相似文献
865.
Sara Santos Bernardes Flávia Alessandra Guarnier Poliana Camila Marinello André Armani Andréa Name Colado Simão Rubens Cecchini Alessandra Lourenço Cecchini 《Cell and tissue research》2014,357(3):803-814
The role of reactive oxygen species (ROS) in muscle protein hydrolysis and protein oxidation in thyrotoxicosis has not been explored. This study indicates that ROS play a role in skeletal muscle wasting pathways in thyrotoxicosis. Two experimental groups (rats) were treated for 5 days with either 3,3′,5-triiodothyronine (HT) or HT with α-tocopherol (HT?+?αT). Two controls were used, vehicle (Control) and control treated with αT (Control?+?αT). Serum T3, peritoneal fat, serum glycerol, muscle and body weight, temperature, mitochondrial metabolism (cytochrome c oxidase activity), oxidative stress parameters and proteolytic activities were examined. High body temperature induced by HT returned to normal when animals were treated with αT, although total body and muscle weight did not. An increase in lipolysis was observed in the HT?+?αT group, as peritoneal fat decreased significantly together with an increase in serum glycerol. GSH, GSSG and total radical-trapping antioxidant parameter (TRAP) decreased and catalase activity increased in the HT group. The glutathione redox ratio was higher in HT?+?αT than in both HT and Control?+?αT groups. Carbonyl proteins, AOPP, mitochondrial and chymotrypsin-like proteolytic activities were higher in the HT group than in the Control. HT treatment with αT restored mitochondrial metabolism, TRAP, carbonyl protein, chymotrypsin-like activity and AOPP to the level as that of the Control?+?αT. Calpain activity was lower in the HT?+?αT group than in HT and Control?+?αT and superoxide dismutase (SOD) activity was higher in the HT?+?αT group than in the Control?+?αT. Although αT did not reverse muscle loss, ROS was involved in proteolysis to some degree. 相似文献
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868.
A two-stage experimental procedure for bioequivalence studies is proposed. The procedure is based on the idea that information from a first-stage experiment can be used to form a predictive distribution for the outcome of a second-stage experiment, thus permitting an assessment of the probability of a successful overall outcome. A systematic numerical study of a variety of possible strategies results in the identification of procedures that lead to substantial increases in efficiency compared with single-stage studies. 相似文献
869.
de Oliveira Marcos Roberto de Souza Izabel Cristina Custódio Brasil Flávia Bittencourt 《Neurochemical research》2021,46(3):482-493
Neurochemical Research - Emodin (EM; 1,3,8-trihydroxy-6-methylanthracene-9,10-dione; C15H10O5) is an anthraquinone and exerts cytoprotective effects, as observed in both in vitro and in vivo... 相似文献
870.