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21.
The extracellular matrix (ECM) acts as a critical factor during morphogenesis. Because the organization of the ECM directly
influences the structure of tissues and organs, a determination of the way that ECM organization is regulated should help
to clarify morphogenesis. We have analyzed the assembly of Del1, an ECM protein produced by endothelial cells in embryos,
in the ECM. Del1 consists of three epidermal growth factor repeats (E1–E3) at its N-terminus and two discoidin domains (C1,
C2) at its C-terminus. Experiments with various deletion mutants of Del1 have revealed that fragments containing the C-terminus
of C1, which has a lectin-like structure, direct deposition in the ECM. The efficiency of deposition varies according to the
presence of other domains in Del1. A fragment containing E3 and C1 has the strongest deposition activity, whereas fragments
containing C2, which is highly homologous to C1, have low deposition activity. Digestion of ECM with hyaluronidase from bovine
testis releases Del1 from the ECM, suggesting that glycosaminoglycans are involved in the deposition of Del1. In vivo gene
transfer experiments have shown that fusion with the deposition domain of Del1 dramatically alters the distribution of exogenous
proteins in mice. Thus, the extent of Del1 deposition may modify the organization of the ECM. 相似文献
22.
A histone lysine methyltransferase activated by non-canonical Wnt signalling suppresses PPAR-gamma transactivation 总被引:4,自引:0,他引:4
23.
24.
Hirao S Wada H Nakagaki K Saraya T Kurai D Mikura S Yasutake T Higaki M Yokoyama T Ishii H Nakata K Aakashi T Kamiya S Goto H 《FEMS immunology and medical microbiology》2011,62(2):182-189
Recently, combination treatment with a macrolide and a steroid for Mycoplasma pneumoniae (Mp) pneumonia has been reported to be effective. Thus, the effect of this combination on a mouse model of lung inflammation associated with Mp extract (the LIMEX mouse) was studied. Interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were induced in Mp extract-treated RAW264.7 cells, and this induction was inhibited by dexamethasone, parthenolide, SB203580 or LY294002. This suggested that Mp extract activates nuclear factor κB-, p38- and PI-3K-linked pro-inflammatory signals. The LIMEX mice were then either treated with or without clarithromycin and/or dexamethasone. Clarithromycin administration enhanced the production of IL-6, TNF-α, macrophage inflammatory protein-1α, monocyte chemotactic protein-1 and RANTES, while their production was perfectly suppressed by the combination of clarithromycin and dexamethasone. IL-17, IL-23, keratinocyte-derived chemokine (KC) and interferon-γ levels were not affected by clarithromycin treatment, but they were significantly suppressed by the combination of dexamethasone and clarithromycin. Collectively, some components of Mp extract provoked an inflammatory reaction in the RAW 264.7 cell line and LIMEX mice. Whereas the lung reaction in LIMEX mice was further exacerbated by clarithromycin treatment, it was resolved by the combinational treatment with clarithromycin and dexamethasone. 相似文献
25.
Satou T Matsuura M Takahashi M Murakami S Hayashi S Sadamoto K Koike K 《化学与生物多样性》2011,8(6):1132-1138
The essential oils extracted from the leaves and the shoots of five Abies species (Pinaceae) growing in Japan, i.e., A. firma, A. homolepis, A. veitchii, A. mariesii, and A. sachalinensis, were characterized by GC-FID and GC/MS analyses. The yields of the essential oils extracted from A. sachalinensis were the highest among them. A significant amount of α-pinene was contained in the essential oils of all the Abies species examined. In A. homolepis and A. veitchii, significant differences in the content of the essential oils were found depending on whether these were extracted from the leaves or from the shoots. Regarding the enantiomeric ratio of α-pinene, the (+)-enantiomer was predominant in the oil extracted from the leaves of A. firma, while (-)-α-pinene was present in higher amounts in the oils of A. veitchii (leaves and shoots), A. mariesii (leaves and shoots), and A. sachalinensis (shoots). The fact that there may be a quantitative and qualitative difference in the components of the essential oils extracted from the different parts of a plant was investigated by cluster analysis. 相似文献
26.
Immobilized glucoamylase sheet was prepared using soluble collagen prepared from cow hide powder as the support material. The immobilized glucoamylase sheet was attached to the rotary disc and the rates of hydrolysis of maltose and soluble starch in the tank were measured. Qualitative discussions are made of the effect of stirring speed of immobilized enzyme disc on the overall reaction rate. 相似文献
27.
Tohno M Kitazawa H Shimosato T Matsumoto M Katoh S Kawai Y Saito T 《FEMS immunology and medical microbiology》2005,44(3):283-288
Toll-like receptor 2 (TLR2) has been shown to mediate cell signaling in response to microbial cell wall components, such as peptidoglycan, lipoteichoic acid, microbial lipoprotein, and zymosan. In this study, we cloned the swine TLR2 and used it to transfect Chinese hamster ovary K-1 cells. We demonstrated that the swine TLR2-expressing transfectant can bind not only zymosan from yeast cell wall components but also intact lactic acid bacteria, resulting in the activation of nuclear factor-kappaB. These findings suggest that the swine TLR2-expressing transfectant can be very useful for the primary screening of immunobiotic microorganisms. 相似文献
28.
Shimosato T Kitazawa H Katoh S Tohno M Iliev ID Nagasawa C Kimura T Kawai Y Saito T 《Biochemical and biophysical research communications》2005,326(4):782-787
Toll-like receptor 9, which is expressed on the surface of antigen presenting cells and which was recently identified in the cytoplasmic follicle, recognizes bacterial CpG oligodeoxynucleotides (ODNs), resulting in the induction of a potent immune response. However, in our previous study, we found that TLR9 potentially recognizes not only CpG ODN but also non-CpG ODN such as AT ODN. Therefore, in the present study, to investigate this possibility, we elucidated the effects of AT ODN on T(H)-1, T(H)-2 type cytokine induction via TLR9 by real-time quantitative PCR analysis and ELISA of the swine TLR9 transfectant. The results demonstrated that the T(H)-1 type cytokines such as interleukin (IL)-12p70 and interferon (IFN)-gamma were strongly induced by AT ODN compared to the unexposed controls, while T(H)-2 type cytokines were not induced. These results indicate that the AT ODN can augment the T(H)-1 immune response, which plays an important role in prevention of allergic responses. Moreover, the swine TLR9 transfectant demonstrated its usefulness for evaluation of immunostimulation by bacterial DNA through the detection of T(H)-1, T(H)-2 type cytokine induction via TLR9 signaling. 相似文献
29.
Miyajima Y Nakamura H Kuwata Y Lee JD Masunaga S Ono K Maruyama K 《Bioconjugate chemistry》2006,17(5):1314-1320
The nido-carborane lipid 2 as a double-tailed boron lipid was synthesized from heptadecanol in five steps. The lipid 2 formed stable liposomes at 25% molar ratio toward DSPC with cholesterol. Transferrin was able to be introduced on the surface of boron liposomes (Tf(+)-PEG-CL liposomes) by the coupling of transferrin to the PEG-CO(2)H moieties of Tf(-)-PEG-CL liposomes. The biodistribution of Tf(+)-PEG-CL liposomes, in which (125)I-tyraminyl inulins were encapsulated, showed that Tf(+)-PEG-CL liposomes accumulated in tumor tissues and stayed there for a sufficiently long time to increase tumor/blood concentration ratio, although Tf(-)-PEG-CL liposomes were gradually released from tumor tissues with time. A boron concentration of 22 ppm in tumor tissues was achieved by the injection of Tf(+)-PEG-CL liposomes at 7.2 mg/kg body weight boron in tumor-bearing mice. After neutron irradiation, the average survival rate of mice not treated with Tf(+)-PEG-CL liposomes was 21 days, whereas that of the treated mice was 31 days. Longer survival rates were observed in the mice treated with Tf(+)-PEG-CL liposomes; one of them even survived for 52 days after BNCT. 相似文献
30.