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51.
Shuichi Kaminogawa Shun-ichi Dosako Kunio Yamauchi Kazuhiko Kinoshita 《Bioscience, biotechnology, and biochemistry》2013,77(2):533-539
Conjugates of αs1-,κ-caseins and αs1-,κ-casein complex were prepared with dimethylaminonaphthalenesulfonate and pyrenebutyrate. Their fluorescence lifetimes and the rotational relaxation times were measured by single photon counting technique and fluorescence depolarization technique, respectively. Both dimethylaminonaphthalenesulfonate and pyrenebutyrate conjugates had more than two lifetimes and the longer lifetime of pyrenebutyrate conjugates was near 140 nsec.The rotational relaxation time of pyrenebutyrate αs1-,κ-casein complex was smaller than that of pyrenebutyrate κ-casein polymer, which suggested that the complex formation of αs1- and κ-casein polymers led to dissociation of the κ-casein polymer.Changes of the rotational relaxation time as a function of weight ratio of αs1- and κ-casein polymers (αs1/κ) showed the specific variation and it was suggested that 4 moles of αs1-κ-casein complex were formed from one mole of κ-casein polymer. 相似文献
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53.
Kou Kayamori Ken-ichi Katsube Kei Sakamoto Yoshio Ohyama Hideaki Hirai Akane Yukimori Yae Ohata Takumi Akashi Masao Saitoh Kiyoshi Harada Hiroyuki Harada Akira Yamaguchi 《PloS one》2016,11(4)
Recent studies have shown that Notch signaling is involved in many types of cancers, including oral squamous cell carcinomas (OSCCs). However, the role of Notch signaling in the tumor microenvironment is not yet fully understood. In this study, we investigated the roles of NOTCH3 signaling in cancer associated fibroblasts (CAFs) in OSCCs. Immunohistochemical study of 93 human tongue OSCC cases indicated that about one third of OSCCs showed NOTCH3 expression in CAFs, and that this expression significantly correlated with tumor-size. In vitro study showed that OSCC cell lines, especially HO1-N-1 cells stimulated NOTCH3 expression in normal human dermal fibroblasts (NHDFs) through direct cell-to-cell contact. Immunohistochemical and morphometric analysis using human OSCC samples demonstrated that NOTCH3 expression in CAFs significantly correlated with micro-vessel density in cancer stroma. In vitro angiogenesis assays involving co-culture of NHDFs with HO1-N-1 and human umbilical endothelial cells (HUVECs), and NOTCH3 knockdown in NHDFs using siRNA, demonstrated that HO1-N-1 cells significantly promoted tube formation dependent on NOTCH3-expression in NHDFs. Moreover, NOTCH3 expression in CAFs was related to poor prognosis of the OSCC patients. This work provides a new insight into the role of Notch signaling in CAFs associated with tumor angiogenesis and the possibility of NOTCH3-targeted molecular therapy in OSCCs. 相似文献
54.
55.
Caroline C. O’Brien Kumaran Kolandaivelu Jonathan Brown Augusto C. Lopes Mie Kunio Vijaya B. Kolachalama Elazer R. Edelman 《PloS one》2016,11(2)
Background
Stacking cross-sectional intravascular images permits three-dimensional rendering of endovascular implants, yet introduces between-frame uncertainties that limit characterization of device placement and the hemodynamic microenvironment. In a porcine coronary stent model, we demonstrate enhanced OCT reconstruction with preservation of between-frame features through fusion with angiography and a priori knowledge of stent design.Methods and Results
Strut positions were extracted from sequential OCT frames. Reconstruction with standard interpolation generated discontinuous stent structures. By computationally constraining interpolation to known stent skeletons fitted to 3D ‘clouds’ of OCT-Angio-derived struts, implant anatomy was resolved, accurately rendering features from implant diameter and curvature (n = 1 vessels, r2 = 0.91, 0.90, respectively) to individual strut-wall configurations (average displacement error ~15 μm). This framework facilitated hemodynamic simulation (n = 1 vessel), showing the critical importance of accurate anatomic rendering in characterizing both quantitative and basic qualitative flow patterns. Discontinuities with standard approaches systematically introduced noise and bias, poorly capturing regional flow effects. In contrast, the enhanced method preserved multi-scale (local strut to regional stent) flow interactions, demonstrating the impact of regional contexts in defining the hemodynamic consequence of local deployment errors.Conclusion
Fusion of planar angiography and knowledge of device design permits enhanced OCT image analysis of in situ tissue-device interactions. Given emerging interests in simulation-derived hemodynamic assessment as surrogate measures of biological risk, such fused modalities offer a new window into patient-specific implant environments. 相似文献56.
Akihiro Ohyama Junko Toyomura Toshiaki Tachibana Seiji Isonishi Haruka Takahashi Hiroshi Ishikawa 《Human cell》2016,29(4):188-196
A cell line, designated NOCC, was established from the ascites of a patient with clear cell adenocarcinoma of the ovary. The cell line has been grown without interruption and continuously propagated by serial passaging (more than 76 times) over 7 years. The cells are spherical to polygonal-shaped, display neoplastic, and pleomorphic features, and grow in a jigsaw puzzle-like pattern while forming monolayers without contact inhibition. The cells proliferate rapidly, but are easily floated as a cell sheet. The population doubling time is about 29 h. The number of chromosomes ranges from 60 to 83. The modal number of chromosomes is 70–74 at the 30th passage. NOCC cells secreted 750.5 ng/ml of VEGF over 3 days of culture. Hypoxia inducible factor-1α (HIF-1α) is a primary regulator of VEGF under hypoxic conditions. NOCC cells were not sensitive to the anticancer drugs BEV, DOX, GEM, ETP, CDDP, or TXT. The graft of NOCC cells to a scid mouse displayed similar histological aspects to the original tumor. Both the NOCC cells and the graft of the NOCC cells gave a positive PAS reaction. 相似文献
57.
We investigated the participation of HDACs in VPA induced apoptosis in Saccharomyces cerevisiae. VPA (20 mM) induced apoptosis in several HDAC mutants, including PRD3 and HDA1-disrupted cells and SIR2 over expressing cells, as well as in wild-type cells but not SIR2-disrupted cells. Intracellular reactive oxygen species and neutral lipid content increased markedly in all kinds of HDAC mutant cells tested except for SIR2-disrupted cells. Thus, these results suggest that 20 mM VPA induces neutral lipid accumulation and apoptosis-like features in S. cerevisiae, and that VPA-induced apoptosis was evaded by deletion of SIR2. 相似文献
58.
K Fukuda Y Koshihara H Oda M Ohyama T Ooyama 《Biochemical and biophysical research communications》1988,151(3):1060-1068
Type V collagen from human placenta remarkably inhibited human umbilical vein endothelial cell (HUVEC) proliferation in a dose-dependent manner when coated on the culture dishes. Other types of collagen (I, III, IV) and fibronectin enhanced HUVEC proliferation under the same conditions. The inhibitory activity of type V collagen was seen not only when it was coated on the dishes, but also when it was directly added into cell culture. The attachment effect of type V collagen did not differ from that of type I collagen. The inhibitory activity is a phenomenon selective for endothelial cells, since type V collagen did not affect the proliferation of human umbilical vein smooth muscle cells, aortic smooth muscle cells, or nasal mucosa fibroblasts. 相似文献
59.
S Hayashi K Ohyama K Yanagi T Yamakawa H Watanabe S Hirakawa S Ohkuma 《The International journal of biochemistry》1990,22(11):1315-1324
1. Three perchloric acid-soluble fractions from ascites of three primary ovarian cancer patients were subjected to Sephacryl S-300 gel filtration, respectively, and three Fr. 1 which were eluted in the vicinity of void volume as minor fractions, were then separated by a systematic affinity chromatography using Vicia unijuga lectin-Sepharose CL-4B column and Arachis hypogaea lectin-Sepharose CL-4B column into three glycoproteins, blood group N antigen precursor glycoprotein with Thomsen-Friedenreich (T) activity, T-active glycoprotein and N antigen precursor glycoprotein, respectively. 2. These nine glycoproteins separated in yields of 0.1-1.3 mg per 100 ml of ascites, were demonstrated to be mucin-type glycoproteins with Mw of 1,791,000-4,921,000 and contained 33.8-56.1% carbohydrates. 相似文献
60.
Cutting edge: profile of chemokine receptor expression on human plasma cells accounts for their efficient recruitment to target tissues 总被引:19,自引:0,他引:19
Nakayama T Hieshima K Izawa D Tatsumi Y Kanamaru A Yoshie O 《Journal of immunology (Baltimore, Md. : 1950)》2003,170(3):1136-1140
We systematically examined the repertoire of chemokine receptors expressed by human plasma cells. Fresh bone marrow plasma cells and myeloma cells consistently expressed CXCR4, CXCR6, CCR10, and CCR3. Accordingly, plasma cells responded to their respective ligands in chemotaxis and very late Ag-4-dependent cell adhesion to fibronectin. Immobilized CXC chemokine ligand (CXCL)16, a novel transmembrane-type chemokine and CXCR6 ligand, also directly induced adhesion of plasma cells without requiring G(alpha i) signaling or divalent cations. Furthermore, we revealed consistent expression of CXCL12 (CXCR4 ligand), CXCL16 (CXCR6 ligand), and CC chemokine ligand 28 (CCR10 and CCR3 ligand) in tissues enriched with plasma cells including bone marrow, and constitutive expression of CXCL12, CXCL16, and CC chemokine ligand 28 by cultured human bone marrow stromal cells. Collectively, plasma cells are likely to be recruited to bone marrow and other target tissues via CXCR4, CXCR6, CCR10, and CCR3. CXCR6 may also contribute to tissue localization of plasma cells through its direct binding to membrane-anchored CXCL16. 相似文献