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161.
Effects of scratching behavior on dermatitis, transepidermal water loss (TEWL) and serum IgE concentrations were examined in NC/Nga (NC) mice with toenails (WIT) and without toenails (WOT). The first study was a preventive treatment done to cut off hind toenails before dermatitis induction and the second study was a therapeutic treatment by cutting off hind toenails of NC mice with severe dermatitis. In the preventive study, scratching behavior significantly increased in both WIT and WOT after dermatitis induction. Skin severity score, TEWL, number of mast cells and serum IgE concentration statistically increased in WIT but not in WOT after dermatitis induction. Histological changes coincided with the skin severity score in WIT, while no changes were observed in WOT. In the therapeutic study, skin severity score in WOT but not in WIT statistically decreased after cutting off the hind toenails. TEWL and numbers of mast cells in WOT were statistically lower compared with findings in WIT. Thus scratching up the skin with toenails seemed to be the most important factor leading to dermatitis in NC mice. 相似文献
162.
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164.
We isolated multiple HSPs from rainbow trout Oncorhynchus mykiss RTG-2 cells and quantitatively compared their mRNA levels between unstressed and heat-shocked cells using real-time RT-PCR analysis. Consequently, we isolated nine cDNAs encoding HSPs from heat-shocked RTG-2 cells, namely, Hsp90betaa, Hsp90betab, Grp78, Hsp70a, Hsc70a, Hsc70b, Cct8, Hsp47, and DnaJ homolog. Quantitative RT-PCR analyses, in which Hsp70b isolated previously was included, showed that the mRNA accumulation levels of Hsp70a, Hsp70b, Hsc70a, Hsc70b, and Hsp47 were significantly increased after heat shock, and the increased levels of two Hsp70s, Hsp70a, and Hsp70b, were most conspicuous. In the case of Hsc70s, the increased level of Hsc70b was more remarkable than that of Hsc70a. These results demonstrate the importance of a comprehensive expression analysis of HSPs for better understanding of the cellular stress response in fish, especially in tetraploid species such as rainbow trout. 相似文献
165.
Akazara scallop troponin-I of Mr 52,000 (52K) was cleaved into two fragments of 17K and 35K with cyanogen bromide. The 17K fragment, along with tropomyosin, inhibited weakly the rabbit actomyosin Mg-ATPase activity, however, the 35K fragment did not affect it at all. In the presence of Akazara scallop TnT (40K component), the 17K fragment, in turn, strongly inhibited the activity, while the 35K fragment did not. The amino acid composition and partial amino acid sequence suggested that the 17K and 35K fragments were derived from C- and N-terminal regions of the TnI, respectively, and that structural similarity to TnIs from other animals is present in the 17K region. 相似文献
166.
Takao Ojima Tomokatsu Ohta Kiyoyoshi Nishita 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2001,129(4)
The complete amino acid sequence of squid Todarodes pacificus troponin C (TnC), which was shown to bind only 1 mol Ca2+/mol, was determined by both the Edman and cDNA methods. The squid TnC is composed of 147 amino acids including an unblocked Pro at the N-terminus and the calculated molecular weight is 17 003.9. Among the four potential Ca2+-binding sites, namely sites I–IV from the N-terminus, only site IV completely satisfied the consensus amino acid sequence for the active Ca2+-binding loop. This indicates that squid TnC possesses a single Ca2+-binding site at the site IV as scallop TnCs [Nishita et al., J. Biol. Chem. 269 (1994) 3464–3468; Ojima et al., Arch. Biochem. Biophys. 311 (1994) 272–276). The sequence homology of squid TnC to TnCs of scallop, arthropods, and rabbit was 61%, 31–38%, and 31%, respectively. In the sequence of the central D/E-helix region of squid and scallop TnCs, a deletion of three amino acids was required to maximize the homology with the other TnCs. 相似文献
167.
Kouichi Yuh Masanori Shimizu Shigeyasu Aoyama Iwao Ichihara Hiroshi Watanabe Makoto Okumura Masahiro Kikuchi 《Cancer immunology, immunotherapy : CII》1989,28(1):1-8
Summary The distribution and number of CD2 (Coulter T11)+ cells, CD16 (Leu 11b)+ cells, Leu 7+ cells, CD8 (OKT 8)+ cells, CD11 (Leu 15)+ cells, CD4 (Leu 3a+3b)+ cells and Leu 10+ or Leu 14+ cells in the liver of patients with hepatocellular carcinoma (HCC) and metastatic liver cancer (MLC) were investigated using monoclonal antibodies and immunohistological methods. In the majority of those with HCC and MLC, CD8 (OKT 8)+, Leu 7+ and CD16 (Leu 11b)+ cells were present both in the tumor and non-tumor tissues. The CD8 (OKT 8)+ cells were more numerous than Leu 7+ and CD16 (Leu 11b)+ cells. No significant difference was observed in the distribution and number of Leu 7+ and CD16 (Leu 11b)+ cells, in any area, in both groups. The number of CD8 (OKT 8)+ cells predominated in the non-tumor area, in both groups. CD11 (Leu 15)+ cells and CD8 (OKT 8)+ cells were present in the ratio of 1:3 or 1:4. The number of CD4 (Leu 3a+3b)+ cells was less than that of CD8 (OKT 8)+ cells in both groups, especially in the tumor area. A few Leu 10+ or Leu 14+ cells were present in all areas, in both groups. In most cases of MLC, the CD8 (OKT 8)+ cells were absent in the tumor area. There was no correlation between the distribution and number of these cells and anti-tumor chemotherapy or non-specific immunotherapy. 相似文献
168.
The present study was performed to examine the effect of angiotensin II on hepatic angiotensinogen production in adrenalectomized rats. The hepatic angiotensinogen mRNA levels in rats without adrenal glands increased 2.8-fold 4 h after the start of angiotensin II infusion. In intact rats with adrenal glands, the hepatic angiotensinogen mRNA levels increased 2.7-fold 4 h after the start. The angiotensin II infusions did not only increase angiotensinogen mRNA levels in intact rats but also increased those in adrenalectomized rats. The results suggest that the angiotensinogen response to ANG II was not dependent on adrenal glucocorticoid. 相似文献
169.
Haruaki Kurasaki Iwao Okamoto Nobuyoshi Morita Osamu Tamura 《Bioorganic & medicinal chemistry letters》2010,20(5):1601-1603
Both enantiomers of elaeocarpenine (1) and its analogs, 21, 22, 25, and 27, were synthesized from bicyclic aldehydes 8–10 via a flexible route previously established for total synthesis of grandisines, and their binding affinities for μ-, κ- and δ-opioid receptor subtypes were evaluated. We found that (9R)-1 exhibited higher affinity than (9S)-1 for all the subtypes, but the enantiomers showed little subtype selectivity. Analogs 21 having a pyrrolizidine skeleton and 27 having a stemona-type skeleton in place of the indolizidine unit of (9S)-1 showed μ-selective and μ-, κ-selective binding, respectively. 相似文献
170.
Liang Sun Jean M. Veith Paula Pera Ralph J. Bernacki Iwao Ojima 《Bioorganic & medicinal chemistry》2010,18(19):7101-7112
Novel paclitaxel-mimicking alkaloids were designed and synthesized based on a bioactive conformation of paclitaxel, that is, REDOR-Taxol. The alkaloid 2 bearing a 5-7-6 tricyclic scaffold mimics REDOR-Taxol best among the compounds designed and was found to be the most potent compound against several drug-sensitive and drug-resistant human cancer cell lines. MD simulation study on the paclitaxel mimics 1 and 2 as well as REDOR-Taxol bound to the 1JFF tubulin structure was quite informative to evaluate the level of mimicking. The MD simulation study clearly distinguishes the 5-6-6 and 5-7-6 tricyclic scaffolds, and also shows substantial difference in the conformational stability of the tubulin-bound structures between 2 and REDOR-Taxol. The latter may account for the large difference in potency, and provides critical information for possible improvement in the future design of paclitaxel mimics. 相似文献