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101.
GABA, Glutamic Acid Decarboxylase, and GABA Transaminase Levels in the Myenteric Plexus in the Intestine of Humans and Other Mammals 总被引:8,自引:2,他引:6
Yukiko Miki Kohtaro Taniyama Chikako Tanaka Takayoshi Tobe 《Journal of neurochemistry》1983,40(3):861-865
Abstract: Regional distribution of endogenous γ- aminobutyric acid (GABA), its synthesizing enzyme, glutamic acid decarboxylase (GAD), and metabolic enzyme, GABA transaminase (GABA-T), were determined in the intestinal tract of guinea pigs and cats and the findings compared with the number of ganglion cells in Auerbach's plexus. There were positive correlations among the GABA contents and the numbers of neural cells of the plexus. The precise localization of GABA and GAD in individual layers (mucosa, circular and longitudinal muscles, and Auerbach's plexus) in the human and cat colon was also determined. The endogenous GABA contents and GAD activity were the highest in Auerbach's plexus in tissues of both species. These results indicate that GABA is synthesized and localized in Auerbach's plexus and probably plays a significant role in the enteric nervous system. 相似文献
102.
A rapid and sensitive method termed “time difference analysis” for the determination of reduced ascorbic acid even in the presence of excess triose reductone has been developed by using a stopped-flow apparatus in excess 2,6-dichlorophenolindophenol. The lowest limit of the concentration of ascorbic acid was about 2 × 10?7m. A single stopped-flow trace can be used for both qualitative and quantitative analysis of ascorbic acid. The contamination of triose reductone, which disturbs the analysis in the ordinary static measurement, can be safely distinguished because of the sluggishness of the reaction. 相似文献
103.
104.
Comparison of R- and S-form lipopolysaccharides fractionated from Escherichia coli UKT-B lipopolysaccharide in pyrogen and Limulus tests 总被引:1,自引:0,他引:1
Tetsuo Komuro Chikako Yomota Toshio Kimura Chris Galanos 《FEMS microbiology letters》1989,60(1):79-84
Different LPS was shown to have a relatively different proportion of O-specific chain-less (R-form) LPS by polyacrylamide gel electrophoresis (PAGE) with sodium deoxycholate (DOC). By using DOC-PAGE, S-form LPS having O-chain with approximately 11 repeating units on average (S-Fr) and O-chain-less LPS (R-Fr) were separated from Escherichia coli UKT-B S-form LPS. Significantly stronger pyrogenicity was observed in R-Fr than in S-Fr when measured on the weight basis. Similar result was observed in Limulus test. Comparing biological activities of different S-form LPS, attention should be given to the amounts of co-existing R-form LPS. 相似文献
105.
Protoplasma - Mitochondrial morphology varies according to development and the physiological conditions of the cell. Here, we performed electron tomography using serial sections to analyze the... 相似文献
106.
Tsutomu Ohashi Kazuhiko Namekata Xiaoli Guo Atsuko Kimura Chikako Harada Takayuki Harada 《Biochemistry and Biophysics Reports》2022
Lighting conditions may affect the development of retinal degenerative diseases such as macular degeneration. In this study, to determine whether the lighting environment affects the progression of degeneration of retinal ganglion cells (RGCs), we examined glutamate/aspartate transporter (GLAST) heterozygous (GLAST+/-) mice, a mouse model of normal tension glaucoma. GLAST+/- mice were reared under a 12-h light-dark cycle (Light/Dark) or complete darkness (Dark/Dark) condition after birth. The total RGC number in the Dark/Dark group was significantly decreased compared with the Light/Dark group at 3 weeks old, while the number of osteopontin-positive αRGCs were similar in both groups. At 6 and 12 weeks old, the total RGC number were not significantly different in both conditions. In addition, the retinal function examined by multifocal electroretinogram were similar at 12 weeks old. These results suggest that lighting conditions may regulate the progression of RGC degeneration in some types of glaucoma. 相似文献
107.
Kurita Kazuki Sakamoto Yuki Naruse Sota Matsunaga Tomoko M. Arata Hideyuki Higashiyama Tetsuya Habu Yoshiki Utsumi Yoshinori Utsumi Chikako Tanaka Maho Takahashi Satoshi Kim Jong-Myong Seki Motoaki Sakamoto Takuya Matsunaga Sachihiro 《Journal of plant research》2019,132(5):629-640
Journal of Plant Research - Histone modification is an important epigenetic mechanism in eukaryotes. Histone acetyltransferase and deacetylase regulate histone acetylation levels antagonistically,... 相似文献
108.
109.
Zhao K Aranzana MJ Kim S Lister C Shindo C Tang C Toomajian C Zheng H Dean C Marjoram P Nordborg M 《PLoS genetics》2007,3(1):e4
A potentially serious disadvantage of association mapping is the fact that marker-trait associations may arise from confounding population structure as well as from linkage to causative polymorphisms. Using genome-wide marker data, we have previously demonstrated that the problem can be severe in a global sample of 95 Arabidopsis thaliana accessions, and that established methods for controlling for population structure are generally insufficient. Here, we use the same sample together with a number of flowering-related phenotypes and data-perturbation simulations to evaluate a wider range of methods for controlling for population structure. We find that, in terms of reducing the false-positive rate while maintaining statistical power, a recently introduced mixed-model approach that takes genome-wide differences in relatedness into account via estimated pairwise kinship coefficients generally performs best. By combining the association results with results from linkage mapping in F2 crosses, we identify one previously known true positive and several promising new associations, but also demonstrate the existence of both false positives and false negatives. Our results illustrate the potential of genome-wide association scans as a tool for dissecting the genetics of natural variation, while at the same time highlighting the pitfalls. The importance of study design is clear; our study is severely under-powered both in terms of sample size and marker density. Our results also provide a striking demonstration of confounding by population structure. While statistical methods can be used to ameliorate this problem, they cannot always be effective and are certainly not a substitute for independent evidence, such as that obtained via crosses or transgenic experiments. Ultimately, association mapping is a powerful tool for identifying a list of candidates that is short enough to permit further genetic study. 相似文献
110.
Sekine Y Yamamoto C Kakisaka M Muromoto R Kon S Ashitomi D Fujita N Yoshimura A Oritani K Matsuda T 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(12):6194-6204
We found that an adaptor protein, signal-transducing adaptor protein (STAP)-2, is a new member of the Fas-death-inducing signaling complex and participates in activation-induced cell death in T cells. STAP-2 enhanced Fas-mediated apoptosis and caspase-8 aggregation and activation in Jurkat T cells. Importantly, STAP-2 directly interacted with caspase-8 and Fas, resulting in enhanced interactions between caspase-8 and FADD in the Fas-death-inducing signaling complex. Moreover, STAP-2 protein has a consensus caspase-8 cleavage sequence, VEAD, in its C-terminal domain, and processing of STAP-2 by caspase-8 was crucial for Fas-induced apoptosis. Physiologic roles of STAP-2 were confirmed by observations that STAP-2-deficient mice displayed impaired activation-induced cell death and superantigen-induced T cell depletion. Therefore, STAP-2 is a novel participant in the regulation of T cell apoptosis after stimulation. 相似文献