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Johan Billen Eline Bauweleers Rosli Hashim Fuminori Ito 《Arthropod Structure & Development》2013,42(3):173-183
We studied the exocrine system of both workers and ergatoid queens of Protanilla wallacei using light, scanning and transmission electron microscopy. Our survey revealed the presence of 26 glands, of which 6 had never been found before in ants. Five of these represent novel discoveries for social insects in general. The overall novel discoveries comprise an epithelial stipes gland, a pharyngeal wall gland, a central petiole gland, a lateral postpetiole gland and a foot-sole gland in the hindleg pretarsi. The intramandibular epithelial gland was already reported in some bees previously, but is now for the first time also reported in ants. The exocrine system of workers and ergatoid queens is very similar, with only the spermathecal gland showing an obvious difference. This is in line with the limited anatomical as well as behavioural difference between both castes in Protanilla compared to the situation in Leptanilla. 相似文献
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The regulation of AVP-induced AQP2 expression was investigated in the present study. AVP administration induced AQP2 expression in a dose-dependent manner in association with an increase in intracellular cAMP concentration. PKA activity was stimulated by AVP but PKA inhibitors did not block the upregulation of AQP2 expression. However, AVP also activated both ERK and CREB pathways, and ERK inhibitor attenuated the upregulation of AQP2 expression. These results therefore indicate that the effect of AVP stimulation to upregulate AQP2 expression involves a PKA-independent pathway. 相似文献
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Hironobu Shirataki Yoshihiro Matsumoto Fuminori Konoike Shuichi Yamamoto 《Biotechnology and bioengineering》2023,120(10):2977-2988
There are few reports of the adoption of continuous processes in bioproduction, particularly the implementation of end-to-end continuous or integrated processes, due to difficulties such as feed adjustment and incorporating virus filtration. Here, we propose an end-to-end integrated continuous process for a monoclonal antibody (mAb) with three integrated process segments: upstream production processes with pool-less direct connection, pooled low pH virus inactivation with pH control and a total flow-through integrated polishing process in which two columns were directly connected with a virus filter. The pooled virus inactivation step defines the batch, and high impurities reduction and mAb recovery were achieved for batches conducted in succession. Viral clearance tests also confirmed robust virus reduction for the flow-through two-column chromatography and the virus filtration steps. Additionally, viral clearance tests with two different hollow fiber virus filters operated at flux ranging from 1.5 to 40 LMH (liters per effective surface area of filter in square meters per hour) confirmed robust virus reduction over these ranges. Complete clearance with virus logarithmic reduction value ≥4 was achieved even with a process pause at the lowest flux. The end-to-end integrated continuous process proposed in this study is amenable to production processes, and the investigated virus filters have excellent applicability to continuous processes conducted at constant flux. 相似文献
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Isamu Akiba Hitoshi Endou Tsutomu Suzuki Saizo Yanaura Fuminori Sakai 《Life sciences》1981,29(10):1057-1063
Chronic administration of morphine caused a marked decrease in the urinary excretion of low molecular weight proteins (LMWP) including α2u-globulin (E.L. Stanley and O.W. Neuhaus, Biochim. Biophys. Acta, , 461–470, 1972), which exist only in male rats. Levels of urinary high molecular weight proteins, such as albumin and γ-globulin, however, were not significantly changed by morphine treatment. The amount of excreted LMWP was observed to decrease 3 days after giving morphine, 0.5 mg/g food, and to recover to the control level within 6 days after withdrawal of morphine. These findings suggest that the decrease of excreted LMWP may be related to the development of morphine dependence in male rats. 相似文献
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Ayako Fukushima Eri Takahashi Junji Saruwatari Hidenobu Tanihara Toshihiro Inoue 《Biochemistry and Biophysics Reports》2020
Exosomes are informative microvesicles associated with intercellular communication via the transfer of many molecular constituents such as proteins, lipids, and nucleic acids; environmental changes and the cellular status around cells greatly affect exosome components. Cells of the retinal pigment epithelium (RPE) are key players in retinal homeostasis. Transforming growth factor (TGF)-β and tumour necrosis factor (TNF)-α are increased in the vitreous and retina in several retinal diseases and activate and undergo epithelial-mesenchymal transition (EMT) in RPE cells. EMT is closely associated with mechanisms of wound healing, including fibrosis and related angiogenesis; however, whether exosome components depend on the cell status, epithelium or mesenchyme and whether these exosomes have pro- or anti-angiogenic roles in the retina are unknown. We performed this study to investigate whether these EMT inducers affect the kinds of components in exosomes secreted from RPE cells and to assess their angiogenic effects. Exosomes were collected from culture media supernatants of a human RPE cell line (ARPE-19) stimulated with or without 10 ng/ml TNF-α and/or 5 ng/ml TGF-β2. NanoSight tracking analysis and immunoblot analysis using exosome markers were used to qualify harvested vesicles. Angiogenic factor microarray analysis revealed that exosomes derived from ARPE-19 cells cultured with TNF-α alone (Exo-TNF) and co-stimulated with TNF-α and TGF-β2 (Exo-CO) contained more angiogenic factors than exosomes derived from control cells (Exo-CTL) or ARPE-19 cells cultured with TGF-β2 alone (Exo-TGF). To assess the effect on angiogenesis, we performed chemotaxis, tube formation, and proliferation assays of human umbilical vein endothelial cells (HUVECs) stimulated with or without exosomes. HUVECs migrated to RPE-derived exosomes, and exosomes derived from ARPE-19 cells accelerated HUVEC tube formation. In contrast, Exo-TNF and Exo-CO reduced HUVEC proliferation. Our findings provide insight into the mechanisms underlying the relation between angiogenesis and exosomes derived from RPE cells. 相似文献