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131.
In addition to being critical for apoptosis, components of the apoptotic pathway, such as caspases, are involved in other physiological processes in many types of cells, including neurons. However, very little is known about their role in dynamic, nonphysically destructive processes, such as axonal arborization and synaptogenesis. We show that caspases were locally active in vivo at the branch points of young, dynamic retinal ganglion cell axonal arbors but not in the cell body or in stable mature arbors. Caspase activation, dependent on Caspase-3, Caspase-9, and p38 mitogen-activated protein kinase (MAPK), rapidly increased at branch points corresponding with branch tip addition. Time-lapse imaging revealed that knockdown of Caspase-3 and Caspase-9 led to more stable arbors and presynaptic sites. Genetic analysis showed that Caspase-3, Caspase-9, and p38 MAPK interacted with Slit1a-Robo2 signaling, suggesting that localized activation of caspases lie downstream of a ligand receptor system, acting as key promoters of axonal branch tip and synaptic dynamics to restrict arbor growth in vivo in the central nervous system. 相似文献
132.
For the cat soleus nerve-muscle system, motor nerve section 48 hr prior to in situ experiment causes certain characteristic transmission losses. Responses to repetitive stimulation are sharply altered: The capacity to transmit iterative stimulation is severely reduced; post-tetanic potentiation and the post-tetanic repetition of soleus nerve terminals responsible for it are also greatly impaired; a phenomenon of post-tetanic depression was frequently observed. However, function of the extramuscular axons appears normal and single impulse transmission is usually not seriously affected. The loss of reactivity to repetitive stimulation has been traced to soleus motor nerve terminals. In view of these data and the known absence of denervation hypersensitivity at this time, the earliest functional failure may be said to occur in the unmyelinated terminals. This subacutely denervated preparation therefore offers a simple means of evaluating motor nerve terminal responsiveness. 相似文献
133.
Tsuchiya Kenji Tomioka Noriko Sano Tomoharu Kohzu Ayato Komatsu Kazuhiro Imai Akio Hayakawa Kazuhide Nagata Takamaru Okamoto Takahiro Hirose Yoshinori 《Limnology》2020,21(1):87-96
Limnology - In Lake Biwa, the largest lake in Japan, external pollutant loads have decreased since the 1980s, leading to improved water quality, such as reduction in biochemical oxygen demand (BOD)... 相似文献
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135.
Kinoshita Kodzue Indo Yoriko Tajima Tomoyuki Kuze Noko Miyakawa Etsuko Kobayashi Toshio Nakamura Tomoyuki Ogata Mitsuaki Okumura Fumihiko Hayakawa Takashi Morimura Naruki Mori Yusuke Okamoto Munehiro Ozaki Yasuhiko Hirata Satoshi 《Primates; journal of primatology》2021,62(3):475-475
Primates - In the original publication of the article, the coauthor “Takashi Hayakawa” was wrongly assigned as co-corresponding author. 相似文献
136.
Nakano Ryohei Morita Taiki Okamoto Yuta Fujiwara Ayaka Yamanaka Takehiko Adachi-Hagimori Tetsuya 《BioControl》2021,66(3):407-418
BioControl - Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is a zoophytophagous predator that feeds on plants as well as prey. Several non-crop host plant species have been used to maintain... 相似文献
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138.
The sixth International Symposium on Autophagy took place in October 2012 in Okinawa, Japan. It brought together scientists from all over the world to cultivate a better understanding of cutting‐edge autophagy research from molecular mechanisms to disease states. 相似文献
139.
Kazushige Yamana Akira Yoshikawa Rie Noda Hidehiko Nakano 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):233-242
Abstract Incorporation of an azobenzene-4,4′-diamide group via a linker arm into the 3′-hydroxyl function of one oligonucleotide segment and the 5′-OH of other oligonucleotide has been described. The binding of the oligonucleotides containing the azobenzene linker was investigated by UV melting behaviors. The azobenzene linker has been shown to be useful as an effective bridge for stabilizing hairpin duplex and triplex. 相似文献
140.
Ken Okamoto Bryan T. Eger Tomoko Nishino Emil F. Pai Takeshi Nishino 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):888-893
Inhibitors of xanthine oxidoreductase block conversion of xanthine to uric acid and are therefore potentially useful for treatment of hyperuricemia or gout. We determined the crystal structure of reduced bovine milk xanthine oxidoreductase complexed with oxipurinol at 2.0 Å resolution. Clear electron density was observed between the N2 nitrogen of oxipurinol and the molybdenum atom of the molybdopterin cofactor, indicating that oxipurinol coordinated directly to molybdenum. Oxipurinol forms hydrogen bonds with glutamate802, arginine880, and glutamate1261, which have previously been shown to be essential for the enzyme reaction. We discuss possible differences in the hypouricemic effect of inhibitors, including allopurinol and newly developed inhibitors, based on their mode of binding in the crystal structures. 相似文献