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101.
Haruka Momose Takuo Mizukami Madoka Kuramitsu Kazuya Takizawa Atsuko Masumi Kumiko Araki Keiko Furuhata Kazunari Yamaguchi Isao Hamaguchi 《PloS one》2015,10(4)
We have previously identified 17 biomarker genes which were upregulated by whole virion influenza vaccines, and reported that gene expression profiles of these biomarker genes had a good correlation with conventional animal safety tests checking body weight and leukocyte counts. In this study, we have shown that conventional animal tests showed varied and no dose-dependent results in serially diluted bulk materials of influenza HA vaccines. In contrast, dose dependency was clearly shown in the expression profiles of biomarker genes, demonstrating higher sensitivity of gene expression analysis than the current animal safety tests of influenza vaccines. The introduction of branched DNA based-concurrent expression analysis could simplify the complexity of multiple gene expression approach, and could shorten the test period from 7 days to 3 days. Furthermore, upregulation of 10 genes, Zbp1, Mx2, Irf7, Lgals9, Ifi47, Tapbp, Timp1, Trafd1, Psmb9, and Tap2, was seen upon virosomal-adjuvanted vaccine treatment, indicating that these biomarkers could be useful for the safety control of virosomal-adjuvanted vaccines. In summary, profiling biomarker gene expression could be a useful, rapid, and highly sensitive method of animal safety testing compared with conventional methods, and could be used to evaluate the safety of various types of influenza vaccines, including adjuvanted vaccine. 相似文献
102.
Sayaka W Satoshi K Van Thuan N Hiroshi O Takafusa H Eiji M Thuy BH Masashi M Teruhiko W 《Zygote (Cambridge, England)》2008,16(3):211-222
Animal cloning methods are now well described and are becoming routine. Yet, the frequency at which live cloned offspring are produced remains below 5%, irrespective of the nuclear donor species or cell type. One possible explanation is that the reprogramming factor(s) of each oocyte is insufficient or not properly adapted for the receipt of a somatic cell nucleus, because it is naturally prepared only for the receipt of a gamete. Here, we have increased the oocyte volume by oocyte fusion and examined its subsequent development. We constructed oocytes with volumes two to nine times greater than the normal volume by the electrofusion or mechanical fusion of intact and enucleated oocytes. We examined their in vitro and in vivo developmental potential after parthenogenetic activation, intracytoplasmic sperm injection (ICSI) and somatic cell nuclear transfer (SCNT). When the fused oocytes were activated parthenogenetically, most developed to morulae or blastocysts, regardless of their original size. Diploid fused oocytes were fertilized by ICSI and developed normally and after embryo transfer, we obtained 12 (4-15%) healthy and fertile offspring. However, enucleated fused oocytes could not support the development of mice cloned by SCNT. These results suggest that double fused oocytes have normal potential for development after fertilization, but oocytes with extra cytoplasm do not have enhanced reprogramming potential. 相似文献
103.
Sugiyama S Di Nardo AA Aizawa S Matsuo I Volovitch M Prochiantz A Hensch TK 《Cell》2008,134(3):508-520
Neural circuits are shaped by experience in early postnatal life. Distinct GABAergic connections within visual cortex determine the timing of the critical period for rewiring ocular dominance to establish visual acuity. We find that maturation of the parvalbumin (PV)-cell network that controls plasticity onset is regulated by a selective re-expression of the embryonic Otx2 homeoprotein. Visual experience promoted the accumulation of non-cell-autonomous Otx2 in PV-cells, and cortical infusion of exogenous Otx2 accelerated both PV-cell development and critical period timing. Conversely, conditional removal of Otx2 from non-PV cells or from the visual pathway abolished plasticity. Thus, the experience-dependent transfer of a homeoprotein may establish the physiological milieu for postnatal plasticity of a neural circuit. 相似文献
104.
Rates for the reaction of nitric oxide with several ferric heme proteins and model compounds have been measured. The NO combination rates are markedly affected by the presence or absence of distal histidine. Elephant myoglobin in which the E7 distal histidine has been replaced by glutamine reacts with NO 500-1000 times faster than do the native hemoglobins or myoglobins. By contrast, there is no difference in the CO combination rate constants of sperm whale and elephant myoglobins. Studies on ferric model compounds for the R and T states of hemoglobin indicate that their NO combination rate constants are similar to those observed for the combination of CO with the corresponding ferro derivatives. The last observation suggests that the presence of an axial water molecule at the ligand binding site of ferric hemoglobin A prevents it from exhibiting significant cooperativity in its reactions with NO. 相似文献
105.
Human mononuclear phagocyte activation antigens 总被引:2,自引:0,他引:2
R F Todd I F Mizukami S D Vinjamuri R D Trochelman W W Hancock D Y Liu 《Blood cells》1990,16(1):167-79; discussion 180-2
Activation of mononuclear phagocytes causes changes in plasma membrane composition that include the expression of surface antigens and receptors. Monoclonal antibody technology has made it possible to identify and characterize newly expressed surface antigens. Among these "activation antigens" is a glycoprotein, Mo3, which (among hematopoietic cells) is selectively expressed by human mononuclear phagocytes that have been exposed to inflammatory factors in vitro and in vivo. Progress toward a functional and structural analysis of Mo3 is described. 相似文献
106.
Function of the lectin domain of Mac-1/complement receptor type 3 (CD11b/CD18) in regulating neutrophil adhesion 总被引:3,自引:0,他引:3
Xia Y Borland G Huang J Mizukami IF Petty HR Todd RF Ross GD 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(11):6417-6426
A lectin function within CD11b mediates both cytotoxic priming of Mac-1/complement receptor type 3 (CR3) by beta-glucan and the formation of transmembrane signaling complexes with GPI-anchored glycoproteins such as CD16b (FcgammaRIIIb). A requirement for GPI-anchored urokinase plasminogen activator receptor (uPAR; CD87) in neutrophil adhesion and diapedesis has been demonstrated with uPAR-knockout mice. In this study, neutrophil activation conditions generating high-affinity (H-AFN) or low-affinity (L-AFN) beta(2) integrin adhesion were explored. A role for the Mac-1/CR3 lectin domain and uPAR in mediating H-AFN or L-AFN adhesion was suggested by the inhibition of Mac-1/CR3-dependent adhesion to ICAM-1 or fibrinogen by beta-glucan or anti-uPAR. The formation of uPAR complexes with Mac-1/CR3 activated for L-AFN adhesion was demonstrated by fluorescence resonance energy transfer. Conversely, Jurkat cell LFA-1 H-AFN-adhesion to ICAM-1 was not associated with uPAR/LFA-1 complexes, any requirement for GPI-anchored glycoproteins, or inhibition by beta-glucan. A single CD11b lectin site for beta-glucan and uPAR was suggested because the binding of either beta-glucan or uPAR to Mac-1/CR3 selectively masked two CD11b epitopes adjacent to the transmembrane domain. Moreover, treatment with phosphatidylinositol-specific phospholipase C that removed GPI-anchored proteins increased CD11b-specific binding of (125)I-labeled beta-glucan by 3-fold and this was reversed with soluble recombinant uPAR. Conversely, neutrophil activation for generation of Mac-1/CR3/uPAR complexes inhibited CD11b-dependent binding of (125)I-labeled beta-glucan by 75%. These data indicate that the same lectin domain within CD11b regulates both the cytotoxic and adhesion functions of Mac-1/CR3. 相似文献
107.
Involvement of the endocannabinoid system in periodontal healing 总被引:1,自引:0,他引:1
Sayaka Kozono Kamal Krishna Biwasa Yumiko Nakajima Yutaka Yonamine Salunya Tancharoen Kazuyuki Noguchi 《Biochemical and biophysical research communications》2010,394(4):928-933
Endocannabinoids including anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are important lipid mediators for immunosuppressive effects and for appropriate homeostasis via their G-protein-coupled cannabinoid (CB) receptors in mammalian organs and tissues, and may be involved in wound healing in some organs. The physiological roles of endocannabinoids in periodontal healing remain unknown. We observed upregulation of the expression of CB1/CB2 receptors localized on fibroblasts and macrophage-like cells in granulation tissue during wound healing in a wound-healing model in rats, as well as an increase in AEA levels in gingival crevicular fluid after periodontal surgery in human patients with periodontitis. In-vitro, the proliferation of human gingival fibroblasts (HGFs) by AEA was significantly attenuated by AM251 and AM630, which are selective antagonists of CB1 and CB2, respectively. CP55940 (CB1/CB2 agonist) induced phosphorylation of the extracellular-regulated kinases (ERK) 1/2, p38 mitogen-activated protein kinase (p38MAPK), and Akt in HGFs. Wound closure by CP55940 in an in-vitro scratch assay was significantly suppressed by inhibitors of MAP kinase kinase (MEK), p38MAPK, and phosphoinositol 3-kinase (PI3-K). These findings suggest that endocannabinoid system may have an important role in periodontal healing. 相似文献
108.
Shimoda Yoshikazu; Shinpo Sayaka; Kohara Mitsuyo; Nakamura Yasukazu; Tabata Satoshi; Sato Shusei 《DNA research》2008,15(1):13-23
Global viewing of protein–protein interactions (PPIs)is a useful way to assign biological roles to large numbersof proteins predicted by complete genome sequence. Here, wesystematically analyzed PPIs in the nitrogen-fixing soil bacteriumMesorhizobium loti using a modified high-throughput yeast two-hybridsystem. The aims of this study are primarily on the providingfunctional clues to M. loti proteins that are relevant to symbioticnitrogen fixation and conserved in other rhizobium species,especially proteins with regulatory functions and unannotatedproteins. By the screening of 1542 genes as bait, 3121 independentinteractions involving 1804 proteins (24% of the total proteincoding genes) were identified and each interaction was evaluatedusing an interaction generality (IG) measure and the generalfeatures of the interacting partners. Most PPIs detected inthis study are novel interactions revealing potential functionalrelationships between genes for symbiotic nitrogen fixationand signal transduction. Furthermore, we have predicted theputative functions of unannotated proteins through their interactionswith known proteins. The results described here represent newinsight into protein network of M. loti and provide useful experimentalclues to elucidate the biological function of rhizobial genesthat can not be assigned directly from their genomic sequence. 相似文献
109.
110.
Sayaka?Morita Syuntaro?HiradateEmail author Yoshiharu?Fujii Jiro?Harada 《Plant Growth Regulation》2005,46(2):125-131
Crude extracts of the leaves of Spiraea prunifolia Sieb. showed high plant-growth-inhibiting activity comparable to that of S. thunbergii extracts. To isolate the causal compound in S. prunifolia, we performed bioassay-directed purification by monitoring the biological activity per unit weight of the organism containing the bioactive compound (total activity). We isolated 1-O-cis-cinnamoyl-β-D-glucopyranose (cis-CG) and identified it as the most important growth-inhibiting constituent in the crude extracts. We did not detect 6-O-(4′-hydroxy-2′-methylenebutyroyl)-1-O-cis-cinnamoyl-β-D-glucopyranose (cis-BCG) in S. prunifolia, though it is a major plant growth inhibitor in S. thunbergii together with cis-CG. We estimated the cis-CG content in S. prunifolia to be 3.84 mmol kg−1 F.W. This amount is comparable to the cis-CG plus cis-BCG content in S. thunbergii (3.59 mmol kg−1 F.W.). This indicates that S. prunifolia and S. thunbergii have equally high potential to inhibit plant growth, and cis-CG acts as the most important plant-growth inhibitor in S. prunifolia extracts. 相似文献