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951.
We investigated the effects of TH-142177 (N-n-butyl-N-[2'-(1-H-tetrazole-5-yl) biphenyl-4-yl]-methyl-(N-carboxy methyl-benzylamino)-acetamide), a novel selective antagonist of angiotensin II type 1-receptor (AT1-R) on angiotensin II (AII)-induced proliferation and migration of vascular smooth muscle cells (VSMC), and on neointimal formation in the rat carotid artery after balloon injury, and on the intracellular signaling by the stimulation of AT1-R. High affinity AII receptor sites were detected in rat VSMC by the use of [125I]Sar1,Ile8-AII. TH-142177 and losartan competed with [125I]Sar1,Ile8-AII for the binding sites in VSMC in a monophasic manner, although PD123177, a selective antagonist of angiotensin II type 2-receptor (AT2-R), had little inhibitory effect, demonstrating the predominant existence of AT1-R in rat VSMC. TH-142177 prevented AII-induced DNA synthesis and migration, with a significant inhibition of 74 and 55%, respectively, at the concentration of 100 nM. AII-induced activation of p21ras, mitogen-activated protein kinase (p42MAPK and p44MAPK), and protein kinase C was significantly (50-78%) inhibited by TH-142177 (100 nM), suggesting that the activation of these enzymes is mediated through the stimulation of AT1-R. Balloon-injured left carotid arteries in rats showed extensive neointimal thickening, and TH-142177 (3 mg/kg) brought out a marked decrease in the neointimal thickening after balloon injury. In conclusion, TH-142177 inhibited AII-induced proliferation and migration of rat VSMC and neointimal formation in the carotid artery after balloon injury, and these effects may be related, in part, to the suppression of ras, p42MAPK and p44MAPK, and protein kinase C activities through the blockade of AT1-R. Thus, TH-142177 may have therapeutic potential for the treatment of vascular diseases such as atherosclerosis and restenosis. 相似文献
952.
Chikashi Nakamura Miki Hasegawa Kazumi Shimada Makoto Shirai Jun Miyake 《Biotechnology and Bioprocess Engineering》2000,5(6):413-417
In this study, a direct detection system for triazine derivative herbicides was developed using the photosynthetic reaction
center (RC) from the purple bacterium,Rhodobacter sphaeroides, and surface plasmon resonance (SPR) apparatus. The histidine-tagged RCs were immobilized on an SPR gold chip using nickel-nitrilotriacetic
acid groups as a binder for one of the triazine herbicide, atrazine. The SPR responses were proportional to the sample concentrations
of atrazine in the range 0.1–1 μg/mL. The sensitivity of the direct detection of atrazine using the RC-assembled sensor chip
was higher than that using the antibody-immobilized chip. The other types of herbicides, DCMU or MCPP, were not detected with
such high sensitivity. The results indicated the high binding selectivity of the RC complex. 相似文献
953.
954.
955.
In Pseudomonas aeriginosa, a gene, ppx, that encodes exopolyphosphatase [exopoly(P)ase; EC 3.6.1.11] of 506 amino acids (56,419 Da) was found downstream of the gene for polyphosphate kinase, ppk. Since ppx is located in the opposite direction of the ppk gene, they do not constitute an operon. The predicted amino acid sequence of PPX is 41% identical with Escherichia coli PPX. The gene product of ppx (paPPX) was overproduced in E. coli, and its activity was evaluated. Orthophosphate (Pi) is released from polyphosphate [poly(P)], the average chain lengths of which are 79 and 750, respectively. The amount of Pi released matched the amount of poly(P) lost. Thus ppx encodes an enzyme that has exopoly(P)ase activity. 相似文献
956.
Norio Onikura Jun Nakajima Takuya Miyake Kouichi Kawamura Shinji Fukuda 《Ichthyological Research》2012,59(2):124-133
The distributions of seven bitterling species and subspecies—Tanakia lanceolata, T. limbata, Acheilognathus tabira nakamurae, A. rhombeus, Rhodeus ocellatus kurumeus, R. ocellatus ocellatus, and R. atremius atremius—in northern Kyushu were predicted using generalized linear models (GLMs) in order to provide information helpful for conserving
native bitterlings and preventing the expansion of alien bitterling species. Predictions were made according to the following
procedure: (1) a set of GLMs for each species was formulated using environmental data from 710 sites that were derived using
digital maps and GIS software, from which the best fit model for each species was selected using the Akaike information criterion
for predicting the fish occurrence, (2) model performance was evaluated based on the receiver-operating characteristics (ROC)
analysis using occurrence and environmental data from 362 sites, and (3) potential distributions of the bitterling were analyzed
using the best fit models and environmental data for 1,272 sites, of which 200 data points without occurrence data were prepared.
The best fit models revealed that 4–6 environmental factors were important in predicting seven bitterling distributions, which
was supported by the area under the ROC curve (AUC) values of these fishes ranging from 0.753 to 0.927. The AUC values in
model evaluation were significantly greater than 0.5 for six fishes, suggesting the moderate accuracies of these best fit
models for predicting the fish distributions. These predictive models can be used for evaluating potential native bitterling
richness and the potential distribution expansion of an alien subspecies. 相似文献
957.
A Miyake T Nishizaki S Ohtsuka Y Yoshimoto T Aono O Tanizawa 《Endocrinologia japonica》1987,34(5):789-792
The plasma concentrations of immunoreactive norepinephrine (NE), dopamine (DA), beta-endorphin (beta-E), luteinizing hormone (LH) and follicle stimulating hormone (FSH) were determined by RIA and HPLC every 6 h until 72 h after iv administration of conjugated estrogens during the midfollicular phase. The LH level showed a biphasic pattern after the injection of conjugated estrogens, i.e. significant suppression (-50%) for 6-42 h after the injection, followed by a rebound increase with a peak (+85%) at 72 h. The plasma levels of immunoreactive beta-E, NE and DA did not change significantly for 72 h after the injection. 相似文献
958.
Neurodevelopmental disorders (NDs) are currently thought to be caused by either genetic
defects or various environmental factors. Recent studies have demonstrated that congenital NDs can
result not only from changes in DNA sequence in neuronal genes but also from changes to the secondary
epigenomic modifications of DNA and histone proteins. Thus, epigenomic assays, as well as genomic
assays, are currently performed for diagnosis of the congenital NDs. It is recently known that
the epigenomic modifications can be altered by various environmental factors, which potentially cause
acquired NDs. Furthermore these alterations can potentially be restored taking advantage of use of reversibility in epigenomics.
Therefore, epigenome-based early diagnosis and subsequent intervention, by using drugs that restore epigenomic
alterations, will open up a new era of preemptive medicine for congenital and acquired NDs. 相似文献
959.
960.
The leaves, steins and ears of tetraploidal wheat, Triticumdurum (genomes AABB) harvested two weeks after heading wereanalyzed for purothionins. There were considerable amounts oftwo iso-purothionins (Pu-1 and Pu-2) in the young kernels ofthe ears, but not in the leaves and stems. The amino acid compositionsof Pu-1 and Pu-2 were in good agreement with those of Pu I andPu II from hexaploidal wheat. As diploidal wheat, T. monococcum(genome AA) is known to produce only Pu I [Fernandez de Caleyaet al. (1976) Genetics 83: 687], we conclude that the threeiso-purothionins, Pu I, Pu II and Pu III in hexaploidal wheat,T. aestivum (genomes AABBDD), are encoded by the genes of genomesA, B and D, respectively. (Received June 28, 1982; Accepted September 24, 1982) 相似文献