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排序方式: 共有474条查询结果,搜索用时 15 毫秒
1.
The cytotoxicity of extracts from rice cultures of five Fusarium avenaceum strains against the porcine epithelial kidney cell-line PK-15 was investigated using the Alamar Blue™ assay. After the identification of known fungal metabolites, cytotoxic extracts were fractionated using semi-preparative reversed-phase HPLC and normal phase LC, and the fractions were tested for cytotoxicity. In this way, two different groups of metabolites were identified as the major cytotoxic principles of the extracts. High concentrations of enniatins, especially enniatins B and B1, inhibited the metabolic activity of PK-15 cells. Furthermore, an unidentified metabolite, produced in high amounts by a strain that produced relatively small amounts of enniatins, was also found to be cytotoxic to PK-15 cells. This study shows that enniatins, a group of cyclic depsipeptides, which have been ignored as significant contributors to the toxicity of fungal extracts, may account for most of the observed effect for F. avenaceum. 相似文献
2.
S. Uhlig Roland Lewis Featherstone 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(3):392-397
To gain more insight into the complex pulmonary interactions of endothelins (ET), we studied airway and vascular responses
to endothelins in isolated perfused rat lungs in the presence of the novel ETB-receptor antagonist BQ788. In particular we focused on airway responses and on prostacyclin release. The effectiveness of
BQ788 in our system was shown by its ability to concentration-dependently prevent vasoconstriction (IC50 0.1μM), bronchoconstriction (IC50 0.1μM) and prostacyclin production (IC50<0.1μM) induced by the ETB-receptor agonist IRL1620 (1nmol). Airway responses to ET-1: ET-1-induced bronchoconstriction was aggravated by BQ123 (1 or
8μM), while BQ788 pretreatment (1 or 8μM) showed no significant effect. Simultaneous treatment with 8μM BQ123 and BQ788 attenuated
the ET-1-induced bronchoconstriction. Vascular responses to ET-1: ET-1 (1nmol)-induced vasoconstriction was potentiated by
BQ788 (1 or 8μM), but attenuated by the ETA-receptor antagonist BQ123 (1μM). In the presence of BQ788 diminished amounts of the stable prostacyclin metabolite 6-keto-PGF1α were detected in the perfusate. Simultaneous treatment with 8μM BQ123 and BQ788 completely prevented the ET-1-induced vasoconstriction.
Conclusions: Both ETA- and ETB-receptors contribute to ET-1-induced vasoconstriction and bronchoconstriction. The ET-1-induced vasoconstriction is attenuated
by stimulation of ETB-receptors, a response that is partly mediated by prostacyclin. Due to the mutual interactions between ETA- and ETB-receptors, simultaneous inhibition of both receptors is required to prevent the deleterious effects of ET-1 on lung functions.
Received: 17 October 1996 / Accepted: 16 May 1997 相似文献
3.
IgG class antibodies to the early antigen complex (EA; D + R components) of the Epstein-Barr virus (EBV) were found by indirect immunofluorescence in titres greater than or equal to 1:10 in 196 (49.4%) out of 397 blood donors and titres greater than or equal to 1:20 in 84 (21.2%) of these subjects. Anti-EA titres of greater than or equal to 1:2560 were detected in 6 sera, anti-EA(D) only in 17 donors (4.3%). Additional EBV-specific antibody tests were performed in sera with anti-EA-IgG titres of greater than or equal to 1:20 (n = 84), including IgM class antibodies to virus capsid antigen (anti-VCA-IgM). Specific IgM revealed active EBV infection in 12 blood donors. There was no correlation between the presence of anti-VCA-IgM and the magnitude of anti-EA-IgG titres. Therefore, it seems to be impossible to define the threshold titre for EA antibodies indicating active EBV infection. For this purpose probably a titre increase should be demonstrated in paired sera. 相似文献
4.
Wenzel Mike Yu Hang Uhlig Annemarie Würnschimmel Christoph Wallbach Manuel Becker Andreas Fisch Margit Chun Felix K. H. Meyer Christian P. Leitsmann Marianne 《International urology and nephrology》2021,53(10):2041-2049
International Urology and Nephrology - To test the value of preoperative and postoperative cystatin C (CysC) as a predictor on kidney function after partial (PN) or radical nephrectomy (RN) in... 相似文献
5.
Elisa Guazzelli Elena Masotti Manfred Kriechbaum Frank Uhlig Giancarlo Galli Elisa Martinelli 《Macromolecular chemistry and physics.》2023,224(3):2200360
Amphiphilic fluorinated copolymers PEGMAx-co-FAy and TEGMAx-co-FAy are prepared by activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP). All polymers present a reversible thermoresponsive lower critical solution temperature-type behavior, and a cloud point temperature (Tc) in the range of 30–60 °C strictly dependent on the length of the oxyethylene side chain, the content of the hydrophobic counits, and the concentration of the solution. Combined small angle X-ray scattering (SAXS) and dynamic light scattering measurements are used to study the self-assembly behavior in water, organic solvents (tetrahydrofuran [THF] and dimethylformamide [DMF]), and a fluorinated solvent (hexafluorobenzene [HFB]). SAXS confirms the formation of compact-globular single-chain self-folded unimer micelles in water below Tc, which generally presents small hydrodynamic diameters (Dh ≤ 8 nm) as a result of the folding of the hydrophobic perfluorohexylethyl acrylate counits. The copolymers are also able to form reverse unimer micelle in HFB. The copolymers are not able to self-assemble in unimer micelles in THF or DMF solutions, in which they adopt conventional random coil conformations. 相似文献
6.
cand. med. Margarete Uhlig 《Virchows Archiv : an international journal of pathology》1921,230(1):76-98
Ohne Zusammenfassung 相似文献
7.
Fedor Kryuchkov Alison Robertson Elizabeth M. Mudge Christopher O. Miles Soetkien Van Gothem Silvio Uhlig 《Toxins》2022,14(6)
Ciguatera poisoning is a global health concern caused by the consumption of seafood containing ciguatoxins (CTXs). Detection of CTXs poses significant analytical challenges due to their low abundance even in highly toxic fish, the diverse and in-part unclarified structures of many CTX congeners, and the lack of reference standards. Selective detection of CTXs requires methods such as liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) or high-resolution MS (LC–HRMS). While HRMS data can provide greatly improved resolution, it is typically less sensitive than targeted LC–MS/MS and does not reliably comply with the FDA guidance level of 0.1 µg/kg CTXs in fish tissue that was established for Caribbean CTX-1 (C-CTX-1). In this study, we provide a new chemical derivatization approach employing a fast and simple one-pot derivatization with Girard’s reagent T (GRT) that tags the C-56-ketone intermediate of the two equilibrating C-56 epimers of C-CTX-1 with a quaternary ammonium moiety. This derivatization improved the LC–MS/MS and LC–HRMS responses to C-CTX-1 by approximately 40- and 17-fold on average, respectively. These improvements in sensitivity to the GRT-derivative of C-CTX-1 are attributable to: the improved ionization efficiency caused by insertion of a quaternary ammonium ion; the absence of adduct-ions and water-loss peaks for the GRT derivative in the mass spectrometer, and; the prevention of on-column epimerization (at C-56 of C-CTX-1) by GRT derivatization, leading to much better chromatographic peak shapes. This C-CTX-1–GRT derivatization strategy mitigates many of the shortcomings of current LC–MS analyses for C-CTX-1 by improving instrument sensitivity, while at the same time adding selectivity due to the reactivity of GRT with ketones and aldehydes. 相似文献
8.
Nötzold A Hüppe M Schmidtke C Blömer P Uhlig T Sievers HH 《Journal of the American College of Cardiology》2001,37(7):1963-1966
OBJECTIVES: We sought to determine whether the quality of life (QoL) is different in patients after aortic valve replacement with mechanical prostheses or pulmonary autografts. BACKGROUND: Quality of life after mechanical valve replacement may be affected by the risk of thromboembolism and anticoagulation, and after autograft implantation, by the risk of degeneration and re-operation especially of the homograft. METHODS: Two groups of 40 patients each--one after the autograft procedure (group I) and one after mechanical valve implantation (group II)--were matched for age, gender and length of follow-up. At latest follow-up, all patients underwent routine echocardiography, the short-form health survey (SF-36) QoL survey and an extensive psychological investigation. RESULTS: Patients with an autograft showed better QoL scales, as compared with mechanical valve recipients. The difference was significant for both the physical (72.72+/-20.00 vs. 60.27+/-26.07, p = 0.021) and psychological health sum scores (74.71+/-21.03 vs. 64.71+/-23.49, p = 0.046) and for the subtests of physical functioning (73.72+/-22.44 vs. 62.77+/-25.42, p = 0.049), physical pain (88.39+/-19.13 vs. 73.36+/-27.08, p < or = 0.006), general health perception (64.37+/-17.88 vs. 51.86+/-22.86, p < or = 0.008) and health change (61.89+/-18.94 vs. 50.11+/-24.37, p = 0.02). The QoL variables did not correlate to pressure gradients, ejection fraction and New York Heart Association functional class. Psychometric tests revealed no meaningful differences between the groups. CONCLUSIONS: This study provides some evidence that patients with pulmonary autografts have greater benefit in terms of QoL, as compared with recipients of mechanical valve substitutes. 相似文献
9.
E Roilides K Uhlig D Venzon P A Pizzo T J Walsh 《The Journal of infectious diseases》1992,166(3):668-673
The effects of granulocyte colony-stimulating factor (G-CSF) and interferon-gamma (IFN-gamma) on the oxidative burst of neutrophils (PMNL) in response to blastoconidia and pseudohyphae of Candida albicans were assessed and compared with those in response to N-FMLP. G-CSF enhanced oxidative burst, as measured by superoxide production, in response to both FMLP and opsonized blastoconidia. The enhancement of oxidative burst in response to FMLP was significantly greater (P = .004) than that in response to blastoconidia (65% and 39%, respectively). G-CSF also enhanced oxidative burst in response to pseudohyphae. IFN-gamma enhanced oxidative burst in response to FMLP and opsonized blastoconidia by 53% and 50%, respectively. Moreover, IFN-gamma significantly enhanced oxidative burst in response to opsonized and nonopsonized hyphae by 86% and 65%, respectively. These results demonstrate that G-CSF and IFN-gamma enhance the oxidative burst of PMNL in response to both blastoconidia and pseudohyphae of C. albicans and suggest an immunomodulatory role of the two cytokines in the host defenses against this fungus. 相似文献
10.
Hammer Hilde Berner Michelsen Brigitte Sexton Joe Uhlig Till Provan Sella A. 《Clinical rheumatology》2021,40(5):1739-1749
Clinical Rheumatology - The associations between fatigue and disease activity in patients with rheumatoid arthritis (RA) have not been defined. The present objectives were to explore in RA patients... 相似文献