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991.
Mathias Robert S.; Mikoshiba Katsuhiko; Michikawa Takayuki; Miyawaki Atsushi; Ives Harlan E. 《American journal of physiology. Cell physiology》1998,274(6):C1456
The effect ofinositol 1,4,5-trisphosphate(IP3) receptor blockade onplatelet-derived growth factor (PDGF), fibroblast growth factor (FGF),endothelin-1 (ET-1), or -thrombin receptor-mediated intracellularCa2+(Ca2+i) release was examined using fura 2 microspectrofluorometry in single Chinese hamster ovary cells andmyoblasts. Blockade of the IP3receptor was achieved by microinjection of heparin or monoclonalantibody (MAb) 18A10 into the IP3type 1 receptor. Heparin completely inhibitedCa2+i release after flash photolysis withcaged IP3 and after exposure toPDGF and FGF. In contrast, heparin failed to blockCa2+i release after -thrombin andET-1. After application of ligand, IP3 levels were five- to sevenfoldhigher for -thrombin than for ET-1 or PDGF.IP3 levels after PDGF and ET-1were comparable. Similar to heparin, MAb 18A10 blockedCa2+i release after PDGF but failed toblock Ca2+i release after ET-1 or-thrombin. These data suggest that the mechanisms of Ca2+i release by tyrosine kinase andcertain 7-transmembrane receptors may differ. Although both receptortypes use the IP3-signaling system, the ET-1 and -thrombin receptors may have a second,alternative mechanism for activatingCa2+i release. 相似文献
992.
A. Sekizawa Atsushi Taguchi Akira Watanabe Takehiko Kimura Hiroshi Saito Takumi Yanaihara Takeshi Sato 《Human genetics》1998,102(4):393-396
We have extended a previously developed method that allows prenatal DNA diagnosis of female fetuses through the isolation
of single nucleated erythrocytes from maternal blood by developing a method that can distinguish between maternal and fetal
nucleated erythrocytes. Nucleated erythrocytes were separated by a density-gradient method and then collected by micromanipulation.
Sex was determined after primer extension preamplification (PEP) of the entire genome of a single cell, and human leukocyte
antigen (HLA)-DQ α type was determined after further amplification of this gene. The HLA-DQ α genotype of fetal erythrocytes
in maternal blood samples and their corresponding paternal and maternal lymphocytes were successfully determined in all cases.
The accuracy of the method was determined by using single nucleated erythrocytes from umbilical cord blood from five normal
deliveries. This is the first demonstration that the fetal HLA-DQ α gene sequences can be identified in a small aliquot of
a single nucleated erythrocyte in maternal blood. We believe that this method ushers in a new era in which the reliability
and accuracy of noninvasive prenatal DNA diagnosis from maternal blood is markedly improved.
Received: 18 April 1997 / Accepted: 1 October 1997 相似文献
993.
Pharbitis seedlings grown in total darkness or continuous far-redirradiation were exposed to 30 min of red irradiation followedby a dark period, and in vivo phytochrome in their cotyledonswas photometrically assayed at various times. Loss of photo-reversibilityof Pfr after the exposure to red light occurred without darkreversion to Pr in cotyledons of both seedlings. Pfr decay inthe former cotyledons was mostly prevented in the first 30 minunder red light illumination, while that in the latter occurredwithout such a lag phase. Pfr was no longer photometricallydetectable by the eighth hr after irradiation at both 18?C and25?C. No evidence has yet been obtained to show a correlation betweenphotometrically detectable phytochrome in vivo and the red far-redreversible responses of flowering. (Received August 6, 1974; ) 相似文献
994.
Fucose sulfate was isolated from the egg jelly glycoproteins of two kinds of sea urchins, Hemicentrotus pulcherrimus and Pseudocentrotus depressus, by mild acid hydrolysis and paper chromatography followed by charcoal and Sephadex G-25 column chromatography. The yields of fucose sulfate were 24 and 20% of the total fucan sulfate from H. pulcherrimus and P. depressus, respectively.On the basis of chemical analysis, periodate oxidation and infrared spectroscopy, the structure of the fucose sulfate of the jelly coat glycoproteins derived from two kinds of sea urchins was proposed to be L-fucose-4-sulfate. 相似文献
995.
Lemna perpusilla 6746, a short-day duckweed, flowered undercontinuous illumination on M-sucrose medium containing CuSO4,AgNO3 and HgCl2, which are SH-inhibitors. The optimum concentrationsof CuSO4, AgNO3 and HgCl2 were 5, 1 and 20 µM, respectively.Other metal ions tested were ineffective, but at least two otherSHinhibitors, potassium ferricyanide and iodoacetamide, alsoinduced long-day flowering at the concentrations of 0.1-1 µM. Adding 50 µM EDTA to the medium prevented the effect ofcupric ion, but not that of other SH-inhibitors. EDTA at 200µM induced some long-day flowering when added to a mediumwith no SH-inhibitors. It also permitted some flowering whenadded together with cupric ion, and accelerated flowering inthe presence of the other SHinhibitors listed above. EDTA andSH-inhibitor effects appeared to be additive. (Received May 25, 1973; ) 相似文献
996.
997.
Atsushi Masamune Naoki Yoshida Shin Hamada Tetsuya Takikawa Tatsuhide Nabeshima Tooru Shimosegawa 《Biochemical and biophysical research communications》2018,495(1):71-77
Pancreatic cancer cells (PCCs) interact with pancreatic stellate cells (PSCs), which play a pivotal role in pancreatic fibrogenesis, to develop the cancer-conditioned tumor microenvironment. Exosomes are membrane-enclosed nanovesicles, and have been increasingly recognized as important mediators of cell-to-cell communications. The aim of this study was to clarify the effects of PCC-derived exosomes on cell functions in PSCs. Exosomes were isolated from the conditioned medium of Panc-1 and SUIT-2 PCCs. Human primary PSCs were treated with PCC-derived exosomes. PCC-derived exosomes stimulated the proliferation, migration, activation of ERK and Akt, the mRNA expression of α-smooth muscle actin (ACTA2) and fibrosis-related genes, and procollagen type I C-peptide production in PSCs. Ingenuity pathway analysis of the microarray data identified transforming growth factor β1 and tumor necrosis factor as top upstream regulators. PCCs increased the expression of miR-1246 and miR-1290, abundantly contained in PCC-derived exosomes, in PSCs. Overexpression of miR-1290 induced the expression of ACTA2 and fibrosis-related genes in PSCs. In conclusion, PCC-derived exosomes stimulate activation and profibrogenic activities in PSCs. Exosome-mediated interactions between PSCs and PCCs might play a role in the development of the tumor microenvironment. 相似文献
998.
Daisuque Kitano Nobuyuki Fujii Sujiono Shigemasa Yamaue Tasuku Kitamura Atsushi Honma Morio Tsukada Takayoshi Nishida Hiroichi Sawada Koh-Ichi Takakura 《Applied Entomology and Zoology》2018,53(4):525-533
Bactrocera carambolae and B. dorsalis (Diptera: Tephritidae) are extremely destructive pests of fruits and vegetables in the Asia-Pacific region. Earlier reports have described that B. carambolae and B. dorsalis, respectively, use mainly star fruit and mango, suggesting a certain level of host partitioning which can be ascribed neither to differences in larval food qualities nor host-specific parasitoid mortality. This study specifically examined reproductive interference (antagonistic sexual interaction) between B. carambolae and B. dorsalis as a potential factor strongly affecting their host partitioning. We observed mating behaviors, especially interspecific courtships and mating, by cohabiting the conspecific and heterospecific pairs together. Consequently, we quantified their effects on the reproductive success of females. Males of both species frequently courted their own females, but they also courted females of other species. Courtship refusal by females was not selective in males of either species. This incomplete discrimination of both sexes led to frequent occurrences of interspecific sexual interactions in both species, but only B. carambolae females showed reduced reproductive success. These results suggest that B. dorsalis, superior in reproductive interference, can occupy high-quality mango, whereas B. carambolae, inferior in reproductive interference, must use low-quality star fruit. 相似文献
999.
Neuronal activity‐dependent local activation of dendritic unfolded protein response promotes expression of brain‐derived neurotrophic factor in cell soma
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1000.
Hirotaka Yamaguchi Jun Ohnishi Atsushi Saito Akio Ohyama Tsukasa Nunome Koji Miyatake Hiroyuki Fukuoka 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(6):1345-1362