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31.
Role of P-Selectin in the Migration of Neutrophils to Chemoattractant-Induced Cutaneous Inflammation in Mice 总被引:1,自引:0,他引:1
The role of P-selectin in the accumulation of neutrophils at acute dermal inflammatory sites induced by chemoattractants, LTB4 and IL-8 was investigated in the mouse. A mouse P-selectin-human IgG chimera bound to mouse neutrophils in vitro in a calcium-dependent manner, as detected by flow cytometry. A rat monoclonal antibody (mAb) against mouse P-selectin, RB40.34 abolished P-selectin-IgG chimera binding to mouse neutrophils, but a control antibody did not. Intradermal injection of LTB4 at a dose of 100 ng/site caused neutrophil accumulation to increase by 3-4 fold, as detected by measuring myeloperoxidase activity. Neutrophil extravasation to perivascular tissue was detected by histochemical observation. The intravenous injection of RB40.34 or the specific LTB4 antagonist, SM-15178, at doses at 5 mg/kg attenuated the accumulation of neutrophils by 55.6% and 70.3%, respectively, but a control antibody showed no effect. Similarly, intradermal administration of IL-8 at a dose of 5 g/site induced significant neutrophil migration into the interstitial tissue of the skin, as followed by measuring myeloperoxidase activity and histopathologic analysis. The intravenous injection of RB40.34 at a dose of 5 mg/kg reduced the neutrophil accumulation by 59.2%; in contrast, a control antibody showed no effect. To our knowledge, this is the first direct demonstration that P-selectin plays a substantial role in LTB4and IL-8-induced neutrophil accumulation in mouse skin. 相似文献
32.
Tamiya G Shinya M Imanishi T Ikuta T Makino S Okamoto K Furugaki K Matsumoto T Mano S Ando S Nozaki Y Yukawa W Nakashige R Yamaguchi D Ishibashi H Yonekura M Nakami Y Takayama S Endo T Saruwatari T Yagura M Yoshikawa Y Fujimoto K Oka A Chiku S Linsen SE Giphart MJ Kulski JK Fukazawa T Hashimoto H Kimura M Hoshina Y Suzuki Y Hotta T Mochida J Minezaki T Komai K Shiozawa S Taniguchi A Yamanaka H Kamatani N Gojobori T Bahram S Inoko H 《Human molecular genetics》2005,14(16):2305-2321
A major goal of current human genome-wide studies is to identify the genetic basis of complex disorders. However, the availability of an unbiased, reliable, cost efficient and comprehensive methodology to analyze the entire genome for complex disease association is still largely lacking or problematic. Therefore, we have developed a practical and efficient strategy for whole genome association studies of complex diseases by charting the human genome at 100 kb intervals using a collection of 27,039 microsatellites and the DNA pooling method in three successive genomic screens of independent case-control populations. The final step in our methodology consists of fine mapping of the candidate susceptible DNA regions by single nucleotide polymorphisms (SNPs) analysis. This approach was validated upon application to rheumatoid arthritis, a destructive joint disease affecting up to 1% of the population. A total of 47 candidate regions were identified. The top seven loci, withstanding the most stringent statistical tests, were dissected down to individual genes and/or SNPs on four chromosomes, including the previously known 6p21.3-encoded Major Histocompatibility Complex gene, HLA-DRB1. Hence, microsatellite-based genome-wide association analysis complemented by end stage SNP typing provides a new tool for genetic dissection of multifactorial pathologies including common diseases. 相似文献
33.
Hashii Koji; Fujiwara Hiroshi; Yoshioka Shinya; Kataoka Nobuhiko; Yamada Shigetoshi; Hirano Takeshi; Mori Takahide; Fujii Shingo; Maeda Michiyuki 《Human reproduction (Oxford, England)》1998,13(10):2738-2744
Human luteal cells have been reported to express human leukocyteantigen-DR and lymphocyte functional antigen-3 on the cell surface,suggesting physiological interaction between luteal cells andT-lymphocytes through the menstrual cycle into early pregnancy.To elucidate the role of peripheral lymphocytes on corpus luteumdifferentiation, the effect of peripheral blood mononuclearcells (PBMC) on steroidogenesis by luteal cells was investigated.The production of Th-2 cytokines such as interleukin (IL)-4and IL-10 by the co-cultured cells was also examined, and theeffects of these cytokines on progesterone production by lutealcells were investigated. Corpora lutea were obtained from eightnon-pregnant women in the luteal phase and five women in earlypregnancy for luteal cell culture. PBMC were isolated from unrelatedwomen in the follicular phase, secretory phase, and early pregnancy.After co-culture with allogenic PBMC for 48 h, progesteroneproduction was significantly enhanced by PBMC from the secretoryphase and early pregnancy in the non-pregnant luteal cell culture.In the pregnant luteal cell culture, a significant increasein progesterone production was also observed by the co-culturewith PBMC from women in early pregnancy, showing that PBMC havea luteotrophic effect. The stimulatory effects of PBMC werealso observed in co-culture conditions which prevented directcell-to-cell interaction with luteal cells, showing the minorinfluence of mixed lymphocyte reaction. By co-culture with PBMC,the production of IL-10, but not IL-4, was significantly augmentedin luteal cell culture derived from non-pregnant women, whereasthe production of both IL-4 and IL-10 was significantly enhancedin the luteal cell culture derived from pregnant women. Moreover,IL-4 and IL-10 promoted progesterone production by culturedluteal cells, especially in the luteal cell culture derivedfrom corpora lutea of early pregnancy. These findings indicatethat PBMC stimulate progesterone production by luteal cellsand suggest the involvement of PBMC in corpus luteum functionand differentiation probably via the Th-2-type lymphocytes. 相似文献
34.
Specific Inhibitory Action of Anisodamine against a Staphylococcal Superantigenic Toxin, Toxic Shock Syndrome Toxin 1 (TSST-1), Leading to Down-Regulation of Cytokine Production and Blocking of TSST-1 Toxicity in Mice 下载免费PDF全文
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Y Ito Y Iguchi T Kashiwagi Y Imanishi 《Journal of biomedical materials research》1991,25(11):1347-1361
Synthesis of nonthrombogenic materials without using biologically active substances was explored. Poly(sodium vinyl sulfonate) is a water-soluble synthetic polymer and activates antithrombin III to exert nonthrombogenicity that was dependent on the molecular weight. Polyetherurethaneurea film was plasma-treated and graft-polymerized with sodium vinyl sulfonate. The graft film showed excellent in vitro and ex vivo nonthrombogenicity by suppressing interactions with plasma proteins and platelets as well as by inactivating blood-clotting factors. 相似文献
38.
Immunoreactive transforming growth factor alpha is commonly present in colorectal neoplasia. 总被引:2,自引:0,他引:2 下载免费PDF全文
S. Tanaka K. Imanishi M. Yoshihara K. Haruma K. Sumii G. Kajiyama S. Akamatsu 《The American journal of pathology》1991,139(1):123-129
Surgical specimens from 19 patients with invasive colorectal cancers and 12 specimens of normal mucosa from the same patients were examined immunohistochemically for the production of the immunoreactive (IR-) transforming growth factor (TGF)-alpha and IR-epidermal growth factor (EGF) with an anti-TGF-alpha monoclonal antibody (MAb) OAL-MTG01 and anti-EGF MAb KEM-10. Immunoreactive TGF-alpha was detected in 16 (84.2%) of 19 colorectal cancers. In contrast, there was no IR-TGF-alpha in the gland cells of normal mucosa. Immunoreactive EGF was detected in 7 (36.8%) of 19 colorectal cancers and 1 (8.3%) of 12 cases of normal mucosa. The production of both IR-TGF-alpha and IR-EGF in colorectal cancer did not differ by histologic type and Dukes' stage. Immunoreactive TGF-alpha was detected at significantly higher incidence than IR-EGF in colorectal cancer. These results indicate that IR-TGF-alpha should prove valuable as a possible tumor marker in colorectal cancers, and it may be very useful in understanding the biology of colorectal cancer. 相似文献
39.
40.
Shigehito Yamada Chigako Uwabe Tomoko Nakatsu-Komatsu Yutaka Minekura Masaji Iwakura Tamaki Motoki Kazuhiko Nishimiya Masaaki Iiyama Koh Kakusho Michihiko Minoh Shinobu Mizuta Tetsuya Matsuda Yoshimasa Matsuda Tomoyuki Haishi Katsumi Kose Shingo Fujii Kohei Shiota 《Developmental dynamics》2006,235(2):468-477
Morphogenesis in the developing embryo takes place in three dimensions, and in addition, the dimension of time is another important factor in development. Therefore, the presentation of sequential morphological changes occurring in the embryo (4D visualization) is essential for understanding the complex morphogenetic events and the underlying mechanisms. Until recently, 3D visualization of embryonic structures was possible only by reconstruction from serial histological sections, which was tedious and time-consuming. During the past two decades, 3D imaging techniques have made significant advances thanks to the progress in imaging and computer technologies, computer graphics, and other related techniques. Such novel tools have enabled precise visualization of the 3D topology of embryonic structures and to demonstrate spatiotemporal 4D sequences of organogenesis. Here, we describe a project in which staged human embryos are imaged by the magnetic resonance (MR) microscope, and 3D images of embryos and their organs at each developmental stage were reconstructed based on the MR data, with the aid of computer graphics techniques. On the basis of the 3D models of staged human embryos, we constructed a data set of 3D images of human embryos and made movies to illustrate the sequential process of human morphogenesis. Furthermore, a computer-based self-learning program of human embryology is being developed for educational purposes, using the photographs, histological sections, MR images, and 3D models of staged human embryos. 相似文献