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51.
J. Börgermann S. Flohé R. J. Scheubel O. Kuss A. Simm F. U. Schade I. Friedrich 《Inflammation research》2007,56(3):126-132
Objective and design: Cardiopulmonary bypass (CPB) impairs monocyte and neutrophil proliferation, cytokine synthesis, and antigen presentation.
This study compares in vivo data with results from an extracorporeal circulation (ECC) model, distinguishing direct effects on cytokine synthesis from
regulatory mechanisms.
Patients and methods: Whole blood from 18 patients prior to, during and after CPB was stimulated with lipopolysaccharide (LPS). Tumor necrosis factor
(TNF)-α, interleukin (IL)-6, and IL-8 levels were measured. Additionally, blood from 4 volunteers was circulated in an ECC
model. Cytokine levels were measured before and during mock ECC.
Results: LPS-induced cytokine synthesis was reduced after CPB (TNF-α: 11 %; IL-6: 29 %; IL-8: 48 % of preoperative values, all p <
0.001). In mock ECC, cytokine production (except IL-8) was suppressed: TNF-α production was lowest 60 min after starting ECC,
IL-6 synthesis was lowest at 90 min (33 % and 15 % vs. pre-ECC levels; both p < 0.001). Patient sera contained cytokine-inhibitory
activity after CPB, an activity not found in mock ECC.
Conclusions: (1) In patients, CPB induces early transient LPS hyporesponsiveness; (2) blood contact with foreign surfaces induces LPS hyporesponsiveness;
(3) serum cytokineinhibitory activities are released after CPB, but not in mock ECC. Impaired leukocyte function may explain
increased susceptibility to infections after CPB.
Received 16 September 2006; accepted without revision by K. Visvanathan 18 October 2006 相似文献
52.
53.
Rudolf Ernst Lang Karl-Heinz Voigt Horst Lorenz Fehm Ernst Friedrich Pfeiffer 《Neuroscience letters》1976,2(1):19-22
Hypothalamic nuclei were removed from frozen sections of rat brain and examined for their corticotropin-releasing activity. The highest concentration was measured in the median eminence. In addition there was significantly more activity detected in the nuclei paraventricularis, supraopticus, suprachiasmaticus and arcuatus than in the other nuclei. 相似文献
54.
Molecular study of frequency of mosaicism in neurofibromatosis 2 patients with bilateral vestibular schwannomas 总被引:5,自引:1,他引:5 下载免费PDF全文
Kluwe L Mautner V Heinrich B Dezube R Jacoby LB Friedrich RE MacCollin M 《Journal of medical genetics》2003,40(2):109-114
Neurofibromatosis 2 (NF2) is a severe autosomal dominant disorder that predisposes to multiple tumours of the nervous system. About half of all patients are founders with clinically unaffected parents. The purpose of the present study was to examine the extent to which mosaicism is present in NF2 founders. A total of 233 NF2 founders with bilateral vestibular schwannomas (BVS) were screened by exon scanning. NF2 mutations were detected in the blood samples of 122 patients (52%). In 10 of the 122 cases, the ratio of mutant to normal alleles was obviously less than 1, suggesting mosaicism. Tumour specimens were available from 35 of the 111 subjects in whom no mutation could be detected in blood specimens. Mutational analysis by exon scanning detected typical NF2 mutations in 21 of the 35 tumours. In nine subjects, the alterations found in tumours could be confirmed to be the constitutional mutation based on finding of identical mutations in pathologically and/or anatomically distinct second tumours. In six other subjects with only a single tumour available, allelic loss of the NF2 gene was found in addition to the mutation in each tumour, suggesting that either the mutation or the deletion of the NF2 gene is probably the constitutional genetic alteration. Our results suggest that failure to find constitutional mutations in blood specimen from these 15 patients was not because of the limitation of the applied screening technique, but the lack of the mutations in their leucocytes, best explained by mosaicism. Extrapolating the rate (15/35 = 43%) of mosaicism in these 35 cases to the 111 NF2 founders with no constitutional NF2 mutations found in their blood, we inferred 48 mosaic subjects (111 x 0.429). Adding the 10 mosaic cases detected directly in blood specimens, we estimate the rate of mosaicism to be 24.8% (58/233) in our cohort of 233 NF2 founders with bilateral vestibular schwannomas. 相似文献
55.
56.
F. Friedrich H. Weiss M. Paulmichl E. Wöll S. Waldegger F. Lang 《Pflügers Archiv : European journal of physiology》1991,418(6):551-555
ATP activates K+ channels by increasing intracellular calcium activity in Madin Darby canine kidney (MDCK) cells. The present study has been performed to test for the involvement of G-proteins and of protein kinase C in the intracellular transmission of these effects. To this end, the effect of ATP on intracellular calcium and K+ channel activity has been studied in cells pretreated with the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) and/or pertussis toxin. The ATP-induced increase of intracellular calcium is not significantly affected by pretreatment with pertussis toxin, is significantly blunted by pretreatment with TPA and is abolished by pretreatment with both pertussis toxin and the phorbol ester. The ATP activation of K+ channels is similarly blunted by pretreatment with TPA, but is not abolished by pretreatment with both the phorbol ester and pertussis toxin. Furthermore, the ATP-induced hyperpolarization is not abolished in cells pretreated with both pertussis toxin and TPA. In those cells, ATP may activate K+ channels by calcium-independent mechanisms or lead to localized increases of intracellular calcium sufficient to activate the K+ channels but escaping detection with fura-2 fluorescence. 相似文献
57.
Friedrich Leibenguth 《Parasitology research》1970,33(3):235-245
Zusammenfassung Nach Infektion mit der Schizogregarine Mattesia dispora zeigt die Haemolymphe ausgewachsener Ephestia-Raupen charakteristische Veränderungen. Während der beiden Schizogonien wird das Muster der ninhydrinpositiven Substanzen um einen Fleck, während Gamogonie und Sporogonie um einen weiteren Fleck unbekannter Natur vermehrt. Beide Substanzen konnten in keinen Zusammenhang mit einer Immunantwort des befallenen Organismus gebracht werden. Die Haemolymphe infizierter und nichtinfizierter Ephestia-Raupen weist den gleichen Lysozymspiegel auf. Der Aminosäurespiegel der Haemolymphe ändert sich nicht durch die Infektion. Mit zunehmender Schwere des Infektionszustandes findet eine sukzessive Hemmung der Haemolymphprotein-Synthese statt. Dies spricht für den Fettkörper als Ort der Synthese.
Mit Unterstützung üer Deutschen Forschungsgemeinschaft. Herrn Ralph Jacob danke ich für seine Mithilfe bei den Versuchen. 相似文献
Alteration of hemolymph of mature larvae of Ephestia infected with Mattesia dispora
Summary The hemolymph of mature larvae of Ephestia kühniella infected with the schizogregarine Mattesia dispora is characteristically altered. During the two schizogonies the pattern of ninhydrinepositive substances is augmented by one spot while during gamogony and sporogony it is further augmented by another spot. It is not clear whether these substances are related immunologically to the infected state. The level of lysozyme activity and of amino acids in the hemolymph remains constant. With increasing injury the synthesis of hemolymph proteins is gradually inhibitied. This evidently indicates that the fat body is the site of synthesis.
Mit Unterstützung üer Deutschen Forschungsgemeinschaft. Herrn Ralph Jacob danke ich für seine Mithilfe bei den Versuchen. 相似文献
58.
Claudia Müller Hermann Herbst Barbara Uchanska-Ziegler Andreas Ziegler Friedrich Schunter Ingeborg Steiert Claude Muller Peter Wernet 《Human immunology》1985,14(4):333-349
The production and serologic, as well as immunochemical properties of a cytotoxic murine IgG monoclonal antibody (Tü109) that precipitates HLA-class I molecules, are described. In the microcytotoxicity assay Tü109 supernatant was demonstrated on a panel of 424 HLA-ABC, -DR, -DQ, -MT typed normal Caucasian blood donors to define an epitope on HLA-B locus molecules in great association with the supertypic specificity Bw4. Reactivity of supernatant showed MHC linked inheritance of the Tü109 determinant and discriminated the HLA-Bw4/Bw6 associated HLA-B locus split antigens. Weak or lack of binding on lymphocytes from some HLA-Bw4 heterozygous individuals, particularly typing for HLA-Bw44, appeared to be due to qualitative and/or quantitative variations of HLA-B locus molecules on the cell surface. With Tü109 ascites fluid, however, extra-reactivity on all HLA-Bw6+ cells was demonstrated. Preferential binding of supernatant to HLA-Bw4, but reactivity of ascites fluid with HLA-Bw6+ molecules in addition, was furthermore confirmed by IEF analysis of antigens immunoprecipitated with Tü109 from cell lysates. Thus the antibody may help to analyze the evolutionary relationship of the diallelic specificities Bw4 and Bw6. 相似文献
59.
Krauth MT Majlesi Y Florian S Bohm A Hauswirth AW Ghannadan M Wimazal F Raderer M Wrba F Valent P 《International archives of allergy and immunology》2005,138(2):111-120
BACKGROUND: Mast cells (MC) are important effector cells of allergic and inflammatory reactions in diverse organs. These cells interact with a number of other immune cells and structural cells in the tissues as well as with proinflammatory mediators and cytokines. The various interactions are considered to be mediated through distinct cell surface membrane receptors on MC. METHODS: In the present study, we have established the cell surface membrane phenotype of human gastrointestinal MC (HGMC) using a panel of monoclonal antibodies and indirect immunofluorescence staining techniques. RESULTS: HGMC were found to react with antibodies against CD29, CD33, CD44, CD45, CD47, CD54, CD55, CD58, CD63, CD117, CD147, CD151, CD172a, and CD203c. By contrast, HGMC did not express detectable amounts of CD1, CD2, CD4, CD5, CD14, CD15, CD16, CD22, CD24, CD25, CD26, CD27, CD28, CD31, CD32, CD34, CD35, CD88, or CD116. The alpha-chain of the IL-3 receptor (CD123) was detectable neither in resting HGMC nor in HGMC exposed to stem cell factor and interleukin-4. CONCLUSIONS: HGMC express a unique profile of surface antigens including the receptor for mast cell growth factor, adhesion-related molecules, and activation-linked membrane antigens. 相似文献
60.
Stimulation of murine lymphocyte blastogenesis by mitogens in heat-killed Histoplasma capsulatum yeast cells. 下载免费PDF全文
In vitro blastogenesis by normal murine splenocytes from several mouse strains has been detected after exposure to heat-killed Histoplasma capsulatum yeast cells. Maximal lymphocyte stimulation induced by 10(4) heat-killed cells resulted in 20- to 45-fold increases in [3H]thymidine uptake by splenocytes when compared with responses by normal unstimulated lymphocytes. The kinetics for this response to heat-killed H. capsulatum cells has shown peak mitogenesis 3 days after culture. Examination of the mitogenic potential of soluble antigen preparations from H. capsulatum has revealed stimulation of lymphocyte blastogenesis with yeast cell sonicates and autolysates but not substances from autoclaved yeast cells. The levels of lymphocyte blastogenesis induced by sonicates or autolysates were comparable to mitogen responses stimulated by heat-killed cells. Preliminary biochemical characterization of the mitogenic factor(s) associated with yeast cell sonicates show two peaks of activity, at 178,000 and less than 12,000 Mr, which have a protein or glycoprotein nature. Finally, analysis of lymphocyte blastogenesis in cultures enriched for selected lymphocyte subpopulations has shown that T lymphocytes are preferentially stimulated by yeast cell mitogens. 相似文献