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1.
Complement components and terminal complement complex in oesophageal smooth muscle of patients with achalasia. 总被引:3,自引:0,他引:3
Wulf B Storch Volker F Eckardt Theo Junginger 《Cellular and molecular biology, including cyto-enzymology》2002,48(3):247-252
This study investigates whether patients with achalasia exhibit autoimmune reactions with subsequent complement activation within oesophageal smooth muscle, vessels and neurones. Oesophageal muscular biopsies from 8 patients undergoing surgery for achalasia and from 6 patients operated for oesophageal cancer were investigated by immunofluorescence for the presence of the complement components C1q, C4, C3c, C3d, C9 and the C9 neoantigen of the terminal C5b-C9 complement complex. Tissues were also investigated for the expression of immunoglobulins (G,A,M) and of the antigens of rubella and varicella zoster viruses. In addition, sera of both patient groups were tested for the presence of autoantibodies against Auerbach's plexus. The terminal complement complex C5b-C9 was found within muscle cells from all patients with achalasia but in only one specimen from a patient with cancer. Two patients with achalasia also exhibited the terminal complement complex as well as IgM within ganglion cells. Muscle cells stained positive for the complement component C9 in all five patients with achalasia in whom this test was performed but in none of the control tissues. In addition, sera from four patients with achalasia contained antibodies against Auerbach's plexus. Studies for the complement components C1q, C4, C3c and for antigens of rubella and varicella zoster viruses revealed negative results in all patients and controls. The results of this study suggest that a complement activation is involved in the autoimmune pathogenesis of achalasia. However, the triggering mechanism of this phenomenon remains to be determined. 相似文献
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Maximilian Schmid Bianca Dufner Julius Dürk Konstanze Bedal Kristina Stricker Lukas Ali Prokoph Christoph Koch Anja K. Wege Henner Zirpel Ger van Zandbergen Rupert Ecker Bogdan Boghiu Uwe Ritter 《PloS one》2015,10(10)
Characterization of host-pathogen interactions is a fundamental approach in microbiological and immunological oriented disciplines. It is commonly accepted that host cells start to change their phenotype after engulfing pathogens. Techniques such as real time PCR or ELISA were used to characterize the genes encoding proteins that are associated either with pathogen elimination or immune escape mechanisms. Most of such studies were performed in vitro using primary host cells or cell lines. Consequently, the data generated with such approaches reflect the global RNA expression or protein amount recovered from all cells in culture. This is justified when all host cells harbor an equal amount of pathogens under experimental conditions. However, the uptake of pathogens by phagocytic cells is not synchronized. Consequently, there are host cells incorporating different amounts of pathogens that might result in distinct pathogen-induced protein biosynthesis. Therefore, we established a technique able to detect and quantify the number of pathogens in the corresponding host cells using immunofluorescence-based high throughput analysis. Paired with multicolor staining of molecules of interest it is now possible to analyze the infection profile of host cell populations and the corresponding phenotype of the host cells as a result of parasite load. 相似文献
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The ultimatum bargaining game (UBG), a widely used method in experimental economics, clearly demonstrates that motives other than pure monetary reward play a role in human economic decision making. In this study, we explore the behaviour and physiological reactions of both responders and proposers in an ultimatum bargaining game using heart rate variability (HRV), a small and nonintrusive technology that allows observation of both sides of an interaction in a normal experimental economics laboratory environment. We find that low offers by a proposer cause signs of mental stress in both the proposer and the responder; that is, both exhibit high ratios of low to high frequency activity in the HRV spectrum. 相似文献
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By using micro disc electrophoresis and micro-diffusion techniques, the interaction of pure DNA-dependent RNA polymerase (EC 2.7.7.6) from Escherichia coli with the template, the substrates and the inhibitors heparin and rifampicin was investigated. The following findings were obtained: (1) heparin converts the 24S and 18S particles of the polymerase into the 13S form; (2) heparin inhibits RNA synthesis by dissociating the enzyme-template complex; (3) rifampicin does not affect the attachment of heparin to the enzyme; (4) the substrates ATP and UTP are bound by enzyme loaded with rifampicin; (5) rifampicin is bound by an enzyme-template complex to the same extent as by an RNA-synthesizing enzyme-template complex. From this it is concluded that the mechanism of the inhibition of RNA synthesis by rifampicin is radically different from that by heparin. As a working hypothesis to explain the inhibitory mechanism of rifampicin, it is assumed that it becomes very firmly attached to a position close to the synthesizing site and only blocks this when no synthesis is in progress. 相似文献
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Zusammenfassung Rezeptoren von Priapulus caudatus und Rhynchelmis limosella werden elektronenmikroskopisch untersucht. Ihre Strukturen stimmen in folgenden Merkmalen überein: Apikal steht eine Zilie, die von regelmäßig angeordneten Mikrovilli umgeben wird. Das Cytoplasma der Mikrovilli ist zentral verdichtet und im übrigen Bereich von Filamenten ausgefüllt, die im Perikaryon wurzeln. Im distalen Teil der Zelle liegt ein reich entwickeltes glattes E. R., darunter folgen Tubuli. Die Zellen werden reich innerviert.Aufgrund der strukturellen Übereinstimmung mit Mechanorezeptoren anderer Tiergruppen wird den Rezeptoren der untersuchten Formen ebenfalls eine mechanorezeptive Funktion zugeschrieben.
Electron microscopic observations on a mechanoreceptor of invertebrates (Priapulida, Oligochaeta)
Summary Epidermal receptor cells of Priapulus caudatus and Rhynchelmis limosella have been investigated with the electron microscope. The following structural peculiarities characterize these cells: an apical cilium is surrounded by regularly arranged microvilli, which contain filaments extending into the cytoplasm of the cell body. The central part of the microvilli is electron dense. The apical part of the cell contains abundant tubules of smooth E. R., below which microtubules are located. The cells are richly innervated.These elements are interpreted to represent mechanoreceptors because they have the above mentioned structures in common with mechanoreceptors of other invertebrate groups.
Für die Überlassung eines Arbeitsplatzes im Anatomischen Institut und im Institut für Pharmakognosie Kiel danken wir Herrn Prof. Dr. W. Bargmann und Herrn Prof. Dr. O. Moritz. 相似文献
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Phosphorylation of solubilized and purified high-affinity (Ca2+ + Mg2+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) of human erythrocyte membranes shows no dependence on cyclic AMP concentration in the range 0.1–1000 μM.Ca2+-dependent phosphoprotein is sensitive to hydroxylamine and molybdate treatment. The phosphate linkage shows maximum stability at low pH values, which is progressively lost as the pH rises, with a shoulder around pH 6. SDS gel electrophoresis of the phosphorylated protein yields a peak which shows relative mobility corresponding to a molecular weight of 145 000 and sensitivity to MgATP-chase and hydroxylamine treatment. This indicates that the phosphoprotein represents the phosphorylated intermediate of the high-affinity (Ca2+ + Mg2+)-ATPase of human erythrocyte membranes. 相似文献
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