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921.
922.
923.
Sohn Joon Hyuk Fukui Dai Nojiri Taro Minowa Kazuhiro Kimura Junpei Koyabu Daisuke 《Journal of Mammalian Evolution》2021,28(2):559-571
Journal of Mammalian Evolution - Anatomy of bat genital organs has been conventionally studied by gross and microscopic observations to date. Here, we employ both histological observation and... 相似文献
924.
Reactive oxygen species (ROS) may attack several types of tissues and chronic exposure to ROS may attenuate various biological functions and increase the risk of several types of serious disorders. It is known that treatments with ROS attack neurons and induce cell death. However, the mechanisms of neuronal change by ROS prior to induction of cell death are not yet understood. Here, it was found that treatment of neurons with low concentrations of hydrogen peroxide induced neurite injury, but not cell death. Unusual bands located above the original collapsin response mediator protein (CRMP)-2 protein were detected by western blotting. Treatment with tocopherol or tocotrienols significantly inhibited these changes in neuro2a cells and cerebellar granule neurons (CGCs). Furthermore, prevention by tocotrienols of hydrogen peroxide-induced neurite degeneration was stronger than that by tocopherol. These findings indicate that neurite beading is one of the early events of neuronal degeneration prior to induction of death of hydrogen peroxide-treated neurons. Treatment with tocotrienols may protect neurite function through its neuroprotective function. 相似文献
925.
The G protein Coupled Receptor (GPCR) superfamily is one of the most important pharmaceutical targets. Studies of GPCRs have long been performed under the assumption that GPCRs function as monomers. However, recent studies have revealed that many GPCRs function as homo- and/or hetero-dimers or higher-order oligomeric molecular complexes. As a result, information about GPCR oligomerization is rapidly accumulating, although the molecular mechanisms of oligomerization are not fully understood. A comprehensive collection of information about oligomerization would accelerate investigations of the molecular mechanisms of GPCRs' oligomerization and involvement in signaling. Hence, we have developed a database, G protein coupled Receptor Interaction Partners DataBase (GRIPDB), which provides information about GPCR oligomerization. The entries in the database are divided into two sections: (I) Experiment Information section and (II) Prediction Information section. The Experiment Information section contains (I-i) experimentally indentified GPCR oligomers and their annotations, and (I-ii) experimentally suggested interfaces for the oligomerization. Since the number of experimentally suggested interfaces is limited, the entries in the Prediction Information section have been introduced to provide information about the oligomerization interfaces predicted by our computational method. The experimentally suggested or computationally predicted interfaces are displayed by 3D graphics, using GPCRs with available coordinates. The information in the GRIPDB, especially that about the interfaces, is useful to investigate the molecular mechanisms of signal transduction via GPCR oligomerization. The GRIPDB is available on the web at the following URL: http://grip.cbrc.jp/GDB/index.html . 相似文献
926.
Sakurai R Li Y Torday JS Rehan VK 《American journal of physiology. Lung cellular and molecular physiology》2011,301(5):L721-L730
There is no effective intervention to prevent or treat bronchopulmonary dysplasia (BPD). Curcumin has potent antioxidant and anti-inflammatory properties, and it modulates signaling of peroxisome proliferator-activated receptor-γ (PPARγ), an important molecule in the pathobiology of BPD. However, its role in the prevention of BPD is not known. We determined 1) if curcumin enhances neonatal lung maturation, 2) if curcumin protects against hyperoxia-induced neonatal lung injury, and 3) if this protection is mediated by blocking TGF-β. Embryonic day 19 fetal rat lung fibroblasts were exposed to 21% or 95% O(2) for 24 h following 1 h of treatment with curcumin. Curcumin dose dependently accelerated e19 fibroblast differentiation [increased parathyroid hormone-related protein (PTHrP) receptor, PPARγ, and adipocyte differentiation-related protein (ADRP) levels and triolein uptake] and proliferation (increased thymidine incorporation). Pretreatment with curcumin blocked the hyperoxia-induced decrease (PPARγ and ADRP) and increase (α-smooth muscle actin and fibronectin) in markers of lung injury/repair, as well as the activation of TGF-β signaling. In a separate set of experiments, neonatal Sprague-Dawley rat pups were exposed to 21% or 95% O(2) for 7 days with or without intraperitoneal administration of curcumin. Analysis for markers of lung injury/repair [PTHrP receptor, PPARγ, ADRP, fibronectin, TGF-β receptor (activin receptor-like kinase 5), and Smad3] and lung morphology (radial alveolar count) demonstrated that curcumin effectively blocks TGF-β activation and hyperoxia-induced lung injury. Therefore, curcumin accelerates lung maturation by stimulating key alveolar epithelial-mesenchymal interactions and prevents hyperoxia-induced neonatal lung injury, possibly by blocking TGF-β activation, suggesting that it is a potential intervention against BPD. 相似文献
927.
928.
Sato M Yoshimura S Hirai R Goto A Kunii M Atik N Sato T Sato K Harada R Shimada J Hatabu T Yorifuji H Harada A 《Traffic (Copenhagen, Denmark)》2011,12(10):1383-1393
VAMP7 or tetanus neurotoxin-insensitive vesicle- associated membrane protein (TI-VAMP) has been proposed to regulate apical transport in polarized epithelial cells, axonal transport in neurons and lysosomal exocytosis. To investigate the function of VAMP7 in vivo, we generated VAMP7 knockout mice. Here, we show that VAMP7 knockout mice are indistinguishable from control mice and display a similar localization of apical proteins in the kidney and small intestine and a similar localization of axonal proteins in the nervous system. Neurite outgrowth of cultured mutant hippocampal neurons was reduced in mutant neurons. However, lysosomal exocytosis was not affected in mutant fibroblasts. Our results show that VAMP7 is required in neurons to extend axons to the full extent. However, VAMP7 does not seem to be required for epithelial cell polarity and lysosomal exocytosis. 相似文献
929.
Susumu Ishihara Osamu Kano Ken Ikeda Reiko Shimokawa Kiyokazu Kawabe Yasuo Iwasaki 《BMC neurology》2011,11(1):137
Background
Pure akinesia (PA) is a distinct form of parkinsonism characterized by freezing phenomena. Little is known about brain tumor-associated PA. We highlight the clinicoradiological changes in a patient with PA and central nervous system (CNS) metastases of natural killer/T-cell lymphoma (NKTL). 相似文献930.
Two new lanostane-type triterpenoids, inonotsutriols D (1) and E (2), were isolated from the sclerotia of Inonotus obliquus (Pers.: Fr.) Pil. (Japanese name: kabanoanatake; Russian name: chaga). Their structures were determined to be lanost-8-ene-3β,22R,24R-triol (1) and lanost-8-ene-3β,22R,24S-triol (2) on the basis of spectral data, including 2D NMR analysis. In addition, major compounds, inotodiol (3), trametenolic acid (4), 3β-hydroxylanosta-8,24-dien-21-al (5), 21-hydroxylanosterol (6), inonotsuoxide A (7) and inonotsuoxide B (8) were identified, and all compounds, except 2, were evaluated for their cancer cell growth inhibitory activity against P388, HL-60, L1210 and KB cell lines. 相似文献