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71.
Vasoactive intestinal peptide (VIP) and peptide histidine isoleucine (PHI) are homologous neuropeptides which share vasodilatory properties. This paper addresses the question of whether PHI exerts its vascular action via a receptor distinct from that for VIP. Radioligand binding experiments were done using [Tyr(125I)10]VIP, [Tyr(125I)22]porcine PHI, [Tyr(125I)10]rat PHI and arterial preparations from rat, bovine and porcine species. The radioiodination of rat PHI by the lactoperoxidase-glucose oxidase method and analysis of the structure of the major radiolabeled derivatives were described. All the receptor binding experiments identified a VIP-preferring receptor irrespective of which radioligand or arterial preparation was utilized. VIP and PHI peptides demonstrated cross-desensitization in studies of relaxation of porcine coronary arterial strips in vitro. The present results favor the conclusion that the vascular actions of the PHI peptides are best explained by binding to a VIP-preferring receptor. 相似文献
72.
Toshio Itoh T. Tanaka Ryozo Nagai Tetsuro Kamiya Toshitami Sawayama Toshio Nakayama Hitonobu Tomoike Harumizu Sakurada Yoshio Yazaki Yusuke Nakamura 《Human genetics》1998,102(4):435-439
Familial long QT syndrome (LQTS) is characterized by prolonged ventricular repolarization. Clinical symptoms include recurrent
syncopal attacks, and sudden death may occur as a result of ventricular tachyarrhythmias. Three genes responsible for this
syndrome (KVLQT1, HERG, and SCN5A) have been identified so far, and mutations have been reported on the basis of partially characterized genomic organization.
To optimize the search for HERG mutations, we have determined the genomic structure of HERG and investigated mutations in LQTS families. Human genomic clones containing the HERG gene were isolated from a human genomic library by using reverse-transcribed polymerase chain reaction (RT-PCR) products
from this gene as probes. We determined exon/intron boundaries and flanking intronic sequences by using primers synthesized
on the basis of the HERG cDNA sequence available in the DNA database. HERG was shown to consist of 15 exons spanning approximately 19 kb on chromosome 7q35. Subsequently, we synthesized oligonucleotide
primers to cover the entire coding region and searched for mutations in 36 Japanese LQTS families. When genomic DNA from each
proband was examined by the PCR/single-strand conformation polymorphism technique followed by direct DNA sequencing, five
novel mutations were detected. Each mutation was present in affected relatives of the respective proband. This work should
increase the efficiency of screening mutations associated with HERG.
Received: 4 November 1997 / Accepted: 5 January 1998 相似文献
73.
Tuija Lauteala Pertti Sistonen Marja-Liisa Savontaus Juha Mykkänen Jaakko Simell Mari Lukkarinen Olli Simell Pertti Aula 《American journal of human genetics》1997,60(6):1479-1486
Lysinuric protein intolerance (LPI) is an autosomal recessive disease characterized by defective transport of cationic amino acids and by hyperammonemia. Linkage analysis in 20 Finnish LPI families assigned the LPI gene locus to the proximal long arm of chromosome 14. Recombinations placed the locus between framework markers D14S72 and MYH7, a 10-cM interval in which the markers D14S742, D14S50, D14S283, and TCRA showed no recombinations with the phenotype. The phenotype was in highly significant linkage disequilibrium with markers D14S50, D14S283, and TCRA. The strongest allelic association obtained with marker TCRA, resulting in a P(excess) value of .98, suggests that the LPI gene locus lies in close proximity to this marker, probably within a distance of < 100 kb. 相似文献
74.
Using gamma distribution and spatial autocorrelation, it was demonstrated that plant biomass per unit area of a pasture grazed by cattle exhibited two kinds of spatial heterogeneity: small-scale heterogeneity caused by grazing and large-scale heterogeneity caused by topography, land aspect, etc. For each of the 10 measurement times from May to August, 100 quadrats 50cm × 50cm were arranged along a straight line 50m long in a pasture, and the plants within the quadrats were harvested at the height of 3cm above the ground surface to measure the dry weight. The data were aggregated into frequency distributions, and gamma distribution and the parameter values were estimated. This analysis showed that with the progression of grazing the amount of biomass decreased and the degree of spatial heterogeneity in biomass, measured per 0.25m2, increased, and due to plant regrowth the trends were reversed. By rearranging the 100 biomass data in order of weight, it was suggested that plots with an extremely large biomass were not grazed by cattle and remained in the pasture. For the same data, variations of biomass along the straight line were divided into two parts based on the moving average: the spatial trend and the residuals which cannot be explained by the trend. In this analysis, 48–75% of the total spatial variation was explained by the trend along the straight line. Analysis using spatial autocorrelation for the actual biomass changes showed that the biomass changes within a range of about 10m on the straight line gave a positive correlation, which indicates a topographical trend in biomass. Spatial autocorrelation for residuals suggested that the spatial changes in biomass along the straight line followed a wave-like or checker-board pattern. Small-scale spatial heterogeneity in plant biomass may be caused by the uneven deposition of excreta by grazing animals, uneven use of the grassland by grazing animals, and uneven dispersal of plant seeds through faeces over the grassland. The possibility that such unevenness might accelerate energy flow in the grassland ecosystem and contribute to grassland sustainability is discussed. 相似文献
75.
Kazutaka Miyamoto Mizuha Akiyama Fumiya Tamura Mari Isomi Hiroyuki Yamakawa Taketaro Sadahiro Naoto Muraoka Hidenori Kojima Sho Haginiwa Shota Kurotsu Hidenori Tani Li Wang Li Qian Makoto Inoue Yoshinori Ide Junko Kurokawa Tsunehisa Yamamoto Tomohisa Seki Masaki Ieda 《Cell Stem Cell》2018,22(1):91-103.e5
76.
Simple determination of mycophenolic acid in human serum by column-switching high-performance liquid chromatography 总被引:4,自引:0,他引:4
Teshima D Kitagawa N Otsubo K Makino K Itoh Y Oishi R 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,780(1):21-26
A column-switching high-performance liquid chromatographic analysis was established to monitor the serum concentration of mycophenolic acid, the active metabolite from mycophenolate mofetil administered for the prophylaxis of acute organ rejection in renal transplantation. The system consisted of two pumps for solvent delivery, a column-switching valve, a precolumn, and a reversed-phase analytical column. The present method enabled us to determine MPA by injecting serum samples directly into HPLC without any pretreatment. The mobile phases with different amounts of organic solvent were delivered to the precolumn and analytical column by separate lines, and samples were applied to the precolumn. The column switching valves were switched automatically following the processes for the elimination of protein and the drug analysis. The peak heights of MPA were linearly related to the concentrations (r=0.999) in the range of 0.1-20 micro g/ml, and the limit of quantification was 0.1 micro g/ml (S/N ratio=3). This method was accurate and reproducible on the basis of the results of recovery (94.0-98.0%) and small coefficient of variations of intra and inter-assay (less than 8.3%). 相似文献
77.
Local and global cerebral blood flow and glucose utilization in the α-galactosidase A knockout mouse model of Fabry disease 总被引:2,自引:0,他引:2
Yoshiaki Itoh Takanori Esaki Michelle Cook Pankaj Qasba † Kazuaki Shimoji § Joseph Alroy ‡ Roscoe O. Brady † Louis Sokoloff David F. Moore† 《Journal of neurochemistry》2001,79(6):1217-1224
Fabry disease is an X-linked lysosomal disorder characterized by deficient alpha-galactosidase A activity and intracellular accumulations of glycosphingolipids, mainly globotriaosylceramide (Gb3). Clinically, patients occasionally present CNS dysfunction. To examine the pathophysiology underlying brain dysfunction, we examined glucose utilization (CMR(glc)) and cerebral blood flow (CBF) globally and locally in 18 brain structures in the alpha-galactosidase A gene knockout mouse. Global CMR(glc) was statistically significantly reduced by 22% in Fabry mice (p < 0.01). All 18 structures showed decreases in local CMR(glc) ranging from 14% to 33%. The decreases in all structures of the diencephalon, caudate-putamen, brain stem, and cerebellar cortex were statistically significant (p < 0.05). Global cerebral blood flow (CBF) and local CBF measured in the same 18 structures were lower in Fabry mice than in control mice, but none statistically significantly. Histological examination of brain revealed no cerebral infarcts but abundant Gb3 deposits in the walls of the cerebral vessels with neuronal deposits localized to the medulla oblongata. These results indicate an impairment in cerebral energy metabolism in the Fabry mice, but one not necessarily due to circulatory insufficiency. 相似文献
78.
Inage-Miyake Y Shimanuki S Itoh T Murakami Y Kimura M Suzuki H Miyake M Toki D Uenishi H Awata T Hamasima N 《Biochemical genetics》2005,43(1-2):79-85
We have obtained a partial cDNA and three BAC clones for the porcine insulin-like growth factor binding protein 1 gene (IGFBP-1). Results of fluorescence in situ and radiation hybrid (RH) mapping assigned this gene to porcine chromosome (SSC) 18q24-qter. We found two types of polymerase chain reaction–restriction-fragment-length polymorphisms (PCR–RFLP) in intron 2 by using FokI and AluI. 相似文献
79.
Kawano T Chen L Watanabe SY Yamauchi J Kaziro Y Nakajima Y Nakajima S Itoh H 《FEBS letters》1999,452(3):355-359
Arachidonic acid (AA) is generated via Rac-mediated phospholipase A2 (PLA2) activation in response to growth factors and cytokines and is implicated in cell growth and gene expression. In this study, we show that AA activates the stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) in a time- and dose-dependent manner. Indomethacin and nordihydroguaiaretic acid, potent inhibitors of cyclooxygenase and lipoxygenase, respectively, did not exert inhibitory effects on AA-induced SAPK/JNK activation, thereby indicating that AA itself could activate SAPK/JNK. As Rac mediates SAPK/JNK activation in response to a variety of stressful stimuli, we examined whether the activation of SAPK/JNK by AA is mediated by Rac1. We observed that AA-induced SAPK/JNK activation was significantly inhibited in Rat2-Rac1N17 dominant-negative mutant cells. Furthermore, treatment of AA induced membrane ruffling and production of hydrogen peroxide, which could be prevented by Rac1N17. These results suggest that AA acts as an upstream signal molecule of Rac, whose activation leads to SAPK/JNK activation, membrane ruffling and hydrogen peroxide production. 相似文献
80.
Kun Liang Dong‐Jin Lee Robert J. Elias Helje Pärnaste Mari‐Ann Mõtus 《Palaeontology》2013,56(4):867-891
Protoheliolites is an early heliolitine coral characterized by closely spaced corallites separated in places by sparse coenenchyme. Growth characteristics in the type species, P. norvegicus, are revealed by detailed analysis based on serial peels and thin sections of coralla from the uppermost Katian of north‐western Estonia. Colonies of this species had a strong ability to recover from damage and partial mortality, resulting in various forms of rejuvenation, regeneration, fusion and reorganization of corallites; in some cases, this involved relatively large areas of undifferentiated soft parts. The shells of commensal cornulitids became enclosed in host coralla during colony growth. Coralla of P. norvegicus exhibit distinctive growth cycles due to responses to seasonal changes. The production of new corallites by coenenchymal increase usually occurred in low‐density bands, in which corallites generally display round to subrounded transverse outlines. In high‐density bands, the corallites became crenulated, their wall thickness increased, septal development was more pronounced, and the amount of coenenchyme increased. In addition to these cyclomorphic changes, there were significant astogenetic changes during growth. Compared with the early stage of colony development, distinctive characteristics in the late astogenetic stage include a decrease in the growth rate of the colony, better coordination among corallites, maximum development of corallite crenulations and septa in high‐density bands, more numerous coenenchymal tubules and a greater proportion of corallum area occupied by coenenchyme. In general, the role of polyps in determining morphological characteristics of individual corallites, such as tabularium area, corallite crenulations and wall thickness, was subordinate to the astogeny of the colony. Growth characteristics including colony‐wide coordination of polyp behaviour and subjugation of individuals to restore the colony following damage suggest a strong astogenetic control and high level of colony integration. Protoheliolites probably arose from a heliolitine genus rather than from a nonheliolitine group as some authors have proposed. 相似文献