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排序方式: 共有2436条查询结果,搜索用时 15 毫秒
1.
Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 相似文献
2.
Sawao Honda Shinobu Hashimoto Benoît Nait-Ali David S. Smith Yusuke Daiko Yuji Iwamoto 《Journal of the American Ceramic Society》2022,105(10):6335-6344
Porous alumina with a highly textured microstructure was fabricated by pulse electric current sintering (PECS) using alumina platelets. Highly oriented porous alumina with a porosity of 3%–50% was obtained by a pressure-controlled method of PECS. The properties of the highly textured porous alumina were measured in two directions. The nitrogen gas permeance and thermal conductivity at room temperature were higher in the direction along the platelet length due to the higher continuity of pores and the connectivity of alumina platelets, respectively. The anisotropy of the thermal conductivity at room temperature was investigated and explained by the effect of grain size of platelets as well as morphology and orientation of pores. The bending strength was higher with the loading direction along the platelet thickness. The thermal shock strength was clearly different in the two directions. The difference in the thermal shock strength was investigated by the measurement of properties and thermal stress analysis. 相似文献
3.
Mie Kurosawa Yosuke Shikama Masae Furukawa Rieko Arakaki Naozumi Ishimaru Kenji Matsushita 《International journal of molecular sciences》2021,22(5)
Immunosenescence is characterized by age-associated changes in immunological functions. Although age- and autoimmune-related sialadenitis cause dry mouth (xerostomia), the roles of immunosenescence and cellular senescence in the pathogenesis of sialadenitis remain unknown. We demonstrated that acquired immune cells rather than innate immune cells infiltrated the salivary glands (SG) of aged mice. An analysis of isolated epithelial cells from SG revealed that the expression levels of the chemokine CXCL13 were elevated in aged mice. Senescence-associated T cells (SA-Ts), which secrete large amounts of atypical pro-inflammatory cytokines, are involved in the pathogenesis of metabolic disorders and autoimmune diseases. The present results showed that SA-Ts and B cells, which express the CXCL13 receptor CXCR5, accumulated in the SG of aged mice, particularly females. CD4+ T cells derived from aged mice exhibited stronger in vitro migratory activity toward CXCL13 than those from young mice. In a mouse model of Sjögren’s syndrome (SS), SA-Ts also accumulated in SG, presumably via CXCL12-CXCR4 signaling. Collectively, the present results indicate that SA-Ts accumulate in SG, contribute to the pathogenesis of age- and SS-related sialadenitis by up-regulating chemokines in epithelial cells, and have potential as therapeutic targets for the treatment of xerostomia caused by these types of sialadenitis. 相似文献
4.
Shohei Minagawa Shoji Fujiwara Takeshi Hashimoto Takashi Hayashita 《International journal of molecular sciences》2021,22(9)
Cyclodextrins (CyDs) are water-soluble host molecules possessing a nanosized hydrophobic cavity. In the realm of molecular recognition, this cavity is used not only as a recognition site but also as a reaction medium, where a hydrophobic sensor recognizes a guest molecule. Based on the latter concept, we have designed a novel supramolecular sensing system composed of Zn(II)-dipicolylamine metal complex-based azobenzene (1-Zn) and 3A-amino-3A-deoxy-(2AS,3AS)-γ-cyclodextrin (3-NH2-γ-CyD) for sensing adenosine-5′-triphosphate (ATP). 1-Zn showed redshifts in the UV-Vis spectra and induced circular dichroism (ICD) only when both ATP and 3-NH2-γ-CyD were present. Calculations of equilibrium constants indicated that the amino group of 3-NH2-γ-CyD was involved in the formation of supramolecular 1-Zn/3-NH2-γ-CyD/ATP. The Job plot of the ICD spectral response revealed that the stoichiometry of 1-Zn/3-NH2-γ-CyD/ATP was 2:1:1. The pH effect was examined and 1-Zn/3-NH2-γ-CyD/ATP was most stable in the neutral condition. The NOESY spectrum suggested the localization of 1-Zn in the 3-NH2-γ-CyD cavity. Based on the obtained results, the metal coordination interaction of 1-Zn and the electrostatic interaction of 3-NH2-γ-CyD were found to take place for ATP recognition. The “reaction medium approach” enabled us to develop a supramolecular sensing system that undergoes multi-point interactions in water. This study is the first step in the design of a selective sensing system based on a good understanding of supramolecular structures. 相似文献
5.
6.
OBJECTIVE: To evaluate what nursing home medical directors actually do, what they and other nursing home personnel believe would be desirable to do, and what problems and deficiencies are perceived. DESIGN: Mail survey with follow-up telephone interview when necessary. SETTING: Forty-five nursing facilities in upstate New York. PARTICIPANTS: The medical directors, administrators, and directors of nursing of the 45 facilities. MEASUREMENTS: Inventory of what medical directors reported as to their actual activities and time spent, and of what they, the administrators, and the directors of nursing felt should be their responsibilities and activities under ideal circumstances. RESULTS: For part-time medical directors, self-reported time spent on medical directorship activities averaged 12 hours per month; of all directors, 45% spent 8 hours or less per month. Proportion of time spent on various specific activities varied widely. There was general agreement that substantially more time should be spent, in particular, on evaluating and addressing problems of adequacy and quality of care, communicating with attending physicians about problems, and assisting with inservice training programs. CONCLUSIONS: To fill the role adequately, more time should be spent by many part-time medical directors, which will require greater financial commitment by facilities and reimbursement systems. Efforts need to made to better coordinate the expectations of medical directors and facility staff. 相似文献
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8.
Tsukada T. Hashimoto Y. Sakata K. Okada H. Ishibashi K. 《Solid-State Circuits, IEEE Journal of》2005,40(1):67-79
A decoupling circuit using an operational amplifier is proposed to suppress substrate crosstalk in mixed-signal system-on-chip (SoC) devices. It overcomes the parasitic inductance problem of on-chip capacitor decoupling. The effect of the proposed decoupling circuit is not limited by parasitic fine impedance. A 0.13-/spl mu/m CMOS test chip showed that substrate noise at frequencies from 40 MHz to 1 GHz was incrementally suppressed by sequentially activating three of the proposed circuits in parallel. The power dissipation of each circuit was 3.3 mW at a 1.0-V power supply. The test chip measurement showed that the proposed decoupling reduced crosstalk by 31% at 200 MHz, whereas it was reduced by 4.4% with capacitor decoupling. This 7:1 ratio, or 17 dB, corresponds to the gain of the opamp. Design of the opamp and its feedback loop for active decoupling is simple, making the opamp useful for SoC applications. 相似文献
9.
I Ezaki M Shingu M Hashimoto T Isayama J Tohmatsu H Kanda M Nobunaga T Watanabe 《Canadian Metallurgical Quarterly》1994,21(11):2005-2010
OBJECTIVE: To better understand the immunoglobulin variable (V) region repertoire of rheumatoid factors (RF). METHODS: We characterized the heavy (H) and light (L) chain gene segments utilized in a monospecific IgG RF secreting hybridoma (AEE111F) which were derived from a patient with rheumatoid arthritis (RA). The hybridoma was established by fusion of a mouse myeloma cell line with bone marrow derived mononuclear cells from a patient with RA. First strand complementary DNA (cDNA) was generated and used for a polymerase chain reaction amplification of the H and L chain V domains. The amplified V domains were sequenced and compared with an extensive database of germline and cDNA V gene segments. RESULTS: The VH sequence was found to be 96% homologous to a previously described fetal VH3 cDNA (60P2). The VL sequence was also highly homologous to the previously described V lambda II gene (96%) derived from a patient with systemic lupus erythematosus which correlated with an 8.12 idiotype (Id), and to an antibacterial antibody against the Haemophilus influenzae type b capsular polysaccharide (94.7%). CONCLUSION: The overlap among this RF VL gene and the 2 reported V lambda sequences of antibodies that expressed anti-DNA related Id and an environmental pathogen specificity suggests that a part of the IgG RF isolated from patients with RA may thus be derived from the physiological natural antibody repertoire during an abnormal immune response and then develop high affinity, monospecific RF by the selection of an antigen driven mechanism. 相似文献
10.
Cell death was analyzed in neurulating mouse embryos after in vivo doses of 2-methoxyethanol (2-ME) that produce anterior neural tube defects. Characterization of 2-ME-induced cell death was performed by evaluating: (1) vital fluorochrome staining in whole embryos applying confocal laser scanning microscopy; (2) characteristics of cell debris in conventional histological sections revealed by light microscopy; and (3) Apoptag in situ immunohistochemical staining for apoptosis using light microscopy. Methods for quantification of cell death identified by these three techniques were explored using computerized image analysis. Physiological cell death in control embryos primarily occurred in the neural crest region during neural fold elevation. Embryos exposed to 2-ME had expanded areas of cell death in the neural crest and also new areas of cell death in medial regions of the anterior neural tube. Both physiological and 2-ME-induced embryonic cell death had morphological, immunohistochemical, and fluorochrome staining characteristics of apoptosis. When fluorescence data from confocal microscopic analysis of vital fluorochrome-stained embryos were analyzed, a dose-dependent increase was found in embryos exposed to 2-ME. Similar results were obtained when cell death was analyzed in either conventional histological sections or sections prepared for immunohistochemical detection of apoptosis. The cell death data obtained in this study correlate with previously observed near-term malformation rates, suggesting that a quantitative relationship exists between 2-ME-induced embryonic cell death and neural tube defects. 相似文献