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21.
The Na+–Ca2+ exchange (NCX) system plays a pivotal role in regulating intracellular Ca2+ concentration in cardiomyocytes, neuronal cells, kidney and a variety of other cells. It performs a particularly important function in regulating cardiac contractility and electrical activity. One of the leading NCX inhibitors is KB‐R9743 (KBR) that appears to exhibit selectivity for Ca2+‐influx‐mode NCX activity (reverse mode of NCX). In this article we reviewed pharmacology of KBR and provide a brief summary of studies with other NCX inhibitors, such as SEA0400 (SEA) and SN‐6 (SN). Potential clinical usefulness of KBR and other NCX inhibitors is still controversial but the reviewed findings may be helpful in designing more selective and clinically useful NCX inhibitors for the treatment of cardiac, neuronal and kidney diseases. 相似文献
22.
Development of new immunoradiometric assay for CA 125 antigen using two monoclonal antibodies produced by immunizing lung cancer cells 总被引:4,自引:0,他引:4
Mihoko Kunimatsu Keigo Endo Tetsuo Nakashima Toshikazu Awaji Tsuneo Saga Yuji Watanabe Yasutaka Kawamura Hitoya Ohta Mitsuru Koizumi Harumi Sakahara Junji Konishi Shingo Fujii Takahide Mori Kanji Torizuka Yoichiro Matsuoka Tsuyoshi Nakagawa Nobuo Yamaguchi 《Annals of nuclear medicine》1988,2(2):73-79
CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen. 相似文献
23.
24.
Tomimori Y Muto T Fukami H Saito K Horikawa C Tsuruoka N Saito M Sugiura N Yamashiro K Sumida M Kakutani S Fukuda Y 《Laboratory investigation; a journal of technical methods and pathology》2002,82(6):789-794
An epicutaneous application of 2,4-dinitrofluorobenzene (DNFB) to a mouse ear caused a transient skin swelling, and the repetition of the challenge enlarged the contact dermatitis. The repeated challenge with DNFB also induced eosinophil infiltration on the application site. Administration of a chymase inhibitor significantly inhibited the ear swelling as well as eosinophil accumulation. An intradermal injection of human chymase to the mouse ear also elicited transient skin swelling and eosinophil infiltration, both of which were augmented in proportion to the number of injections. Human serum albumin and heat-inactivated chymase failed to induce such skin reactions, suggesting the participation of proteolytic activity of the enzyme. In addition, chymase stimulated eosinophil migration in vitro in a concentration-dependent manner. Taken together, these observations suggest that mast cell chymase may contribute to development of the DNFB-induced dermatitis, probably by promoting eosinophil infiltration. It is therefore possible that chymase plays a role in pathogenesis of chronic dermatitis such as atopic dermatitis. 相似文献
25.
Biological activities of Bacteroides forsythus lipoproteins and their possible pathological roles in periodontal disease 总被引:2,自引:0,他引:2
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![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hasebe A Yoshimura A Into T Kataoka H Tanaka S Arakawa S Ishikura H Golenbock DT Sugaya T Tsuchida N Kawanami M Hara Y Shibata K 《Infection and immunity》2004,72(3):1318-1325
Bacteroides forsythus is a gram-negative, anaerobic, fusiform bacterium and is considered to be an etiological agent in periodontal disease. A lipoprotein fraction prepared from B. forsythus cells by Triton X-114 phase separation (BfLP) activated human gingival fibroblasts and a human monocytic cell line, THP-1, to induce interleukin-6 production and tumor necrosis factor alpha production. BfLP was found to be capable of inducing nuclear factor-kappaB translocation in human gingival fibroblasts and THP-1 cells. By using Chinese hamster ovary K1 cells transfected with Toll-like receptor genes together with a nuclear factor-kappaB-dependent CD25 reporter plasmid, it was found that signaling by BfLP was mediated by Toll-like receptor 2 but not by CD14 or Toll-like receptor 4. BfLP induced apoptotic cell death in human gingival fibroblasts, KB cells (an oral epithelial cell line), HL-60 cells (a human myeloid leukemia cell line), and THP-1 cells but not in MOLT4 cells (a T-cell leukemia cell line). Caspase-8, an initiator caspase in apoptosis, was found to be activated in these cells in response to BfLP stimulation. Thus, this study suggested that BfLP plays some etiological roles in oral infections, especially periodontal disease, by induction of cell activation or apoptosis. 相似文献
26.
Ryuei Maeda Nobuo Ihara Reiko Takada Tadashi Kondo Emyo Nakano Toshiko Yamato 《Pathology international》1971,21(1):151-155
A new vital staining method with neutral red has been established where by cerebral ganglion cells can be stained in vivo . 相似文献
27.
Iwasaki Y Shibata N Ninomiya M Kurita K Nakabayash N Ishihara K 《Journal of biomaterials science. Polymer edition》2002,13(3):323-335
Heparinization is believed to be one of the methods to suppress thrombus formation on blood-contacting surfaces. However, this study hypothesizes that heparinization alone might not be sufficient to provide a blood-compatible surface; that is, a surface property that resists biofouling is necessary to obtain an effective heparin-modified surface. 2-Methacryloyloxyethyl phosphorylcholine (MPC) polymers with 2-aminoethyl methacrylate (AEMA) were synthesized to immobilize heparin through ionic bonding. The primary amino groups of AEMA were considered to be the polymer surface because the zeta-potential of the surface was positive when the mole fraction of the AEMA units was above 0.2. The antithrombogenic character of the polymer surface modified with heparin was evaluated by both Lee-White and microsphere column methods. The coagulation period of human whole blood in the absence of anticoagulant in glass tubing coated with the MPC polymer was longer than that in the original glass tube. Cell adhesion was completely inhibited on the MPC polymer surface after contact with human whole blood without anticoagulant. However, many adherent blood cells were observed on poly(2-ethylhexyl methacrylate-co-AEMA) (no MPC unit) even after heparinization. These results strongly indicate that the MPC polymer is a useful substrate where the heparin works well and that the heparin-immobilized MPC polymer has superior blood compatibility to the simple MPC polymer. 相似文献
28.
Evaluation of a Membrane Filter Assay System, Ortho HCV Ab Quik Pack, for Detection of Anti-Hepatitis C Virus Antibody
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Takanari Kodama Satoshi Ichiyama Kumiko Sato Toshi Nada Nobuo Nakashima 《Journal of clinical microbiology》1998,36(5):1439-1440
A simple membrane immunoassay assay system, Quik Pack, for the detection of hepatitis C virus antibody was compared with two enzyme-linked immunosorbent assays (ELISAs) in a study of 600 serum samples. Quik Pack exhibited excellent sensitivity and specificity: 96.0 and 99.7%, respectively, versus the ELISA-2 and 99.7 and 99.4%, respectively, versus the ELISA-3. 相似文献
29.
An invasion-independent pathway of blood-borne metastasis: a new murine mammary tumor model
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![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sugino T Kusakabe T Hoshi N Yamaguchi T Kawaguchi T Goodison S Sekimata M Homma Y Suzuki T 《The American journal of pathology》2002,160(6):1973-1980
It is generally believed that active invasion by cancer cells is essential to the metastatic process. In this report, we describe a murine mammary tumor (MCH66) model of metastasis that does not require invasion into the vascular wall of both the primary tumor and the target organ, in this case, the lung. The process involves intravasation of tumor nests surrounded by sinusoidal blood vessels, followed by intravascular tumor growth in the lung, without penetration of the vascular wall during the process. Comparative studies using a nonmetastatic MCH66 clone (MCH66C8) and another highly invasive metastatic cell line (MCH416) suggested that high angiogenic activity and sinusoidal remodeling of tumor blood vessels were prerequisites for MCH66 metastasis. Differential cDNA analysis identified several genes that were overexpressed by MCH66, including genes for the angiogenesis factor pleiotrophin, and extracellular matrix-associated molecules that may modulate the microenvironment toward neovascularization. Our analyses suggest that tumor angiogenesis plays a role in the induction of invasion-independent metastasis. This model should prove useful in screening and development of new therapeutic agents for cancer metastasis. 相似文献
30.
Identification of a novel adhesion molecule involved in the virulence of Legionella pneumophila
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![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Legionella pneumophila is an intracellular bacterium, and its successful parasitism in host cells involves two reciprocal phases: transmission and intracellular replication. In this study, we sought genes that are involved in virulence by screening a genomic DNA library of an L. pneumophila strain, 80-045, with convalescent-phase sera of Legionnaires' disease patients. Three antigens that reacted exclusively with the convalescent-phase sera were isolated. One of them, which shared homology with an integrin analogue of Saccharomyces cerevisiae, was named L. pneumophila adhesion molecule homologous with integrin analogue of S. cerevisiae (LaiA). The laiA gene product was involved in L. pneumophila adhesion to and invasion of the human lung alveolar epithelial cell line A549 during in vitro coculture. However, its presence did not affect multiplication of L. pneumophila within a U937 human macrophage cell line. Furthermore, after intranasal infection of A/J mice, the laiA mutant was eliminated from lungs and caused reduced mortality compared to the wild isolate. Thus, we conclude that the laiA gene encodes a virulence factor that is involved in transmission of L. pneumophila 80-045 and may play a role in Legionnaires' disease in humans. 相似文献