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1.
M. v. Schelhorn 《Archives of microbiology》1959,34(1):36-57
Zusammenfassung An dem Modell — Benzoesäure als Beispiel eines Zellgiftes und Bierhefe als Vertreter der Mikroorganismen — wurden die Gesetzmäßigkeiten der gegenseitigen Beeinflussung beider Faktoren in ihrer Wirkung auf die Mikroorganismenzelle untersucht. Es wurde dabei der Einfluß verschieden hoher Benzoesäurekonzentrationen bei Temperaturen von 0°C bis zu Temperaturen im Bereich thermischer Abtötung der Hefe (55°C) auf die Vermehrungs- bzw. Absterbegeschwindigkeiten der Hefezellen und auf die Temperaturquotienten dieser Geschwindigkeiten studiert.Benzoesäurezusätze, die im optimalen Temperaturbereich nicht letal sind, verzögern die Vermehrung der Hefezellen und können bei verhältnisaäßig tiefen und hohen Temperaturen die sonst bei diesen Temperaturen noch mögliche Vermehrung hemmen.Im letalen Temperaturbereich bewirken auch niedrige Benzoesäurezusätze starke Beschleunigung des temperaturbedingten Absterbens. Das Absterben der Hefezellen unter der Wirkung letaler Benzoesäurekonzentrationen erfolgt allgemein um so schneller, je höher die Temperatur und die Konzentration an Zellgift ist. Die Temperaturquotienten der Absterbegeschwindigkeit unter der Wirkung verschieden hoher Benzoesäurekonzentrationen zeigen in verschiedenen Temperaturbereichen charakteristische Werte, die gewisse schlüsse auf die Natur des temperaturbedingten und benzoesäurebedington Absterbens zulassen. 相似文献
2.
Loos Jacqueline Krauss Jochen Lyons Ashley Föst Stephanie Ohlendorf Constanze Racky Severin Röder Marina Hudel Lennart Herfert Volker Tscharntke Teja 《Biodiversity and Conservation》2021,30(8-9):2415-2432
Biodiversity and Conservation - Across Europe, calcareous grasslands become increasingly fragmented and their quality deteriorates through abandonment and land use intensification, both affecting... 相似文献
3.
Wolfgang Lorenz Constanze Buhrmann Ali Mobasheri Cora Lueders Mehdi Shakibaei 《Arthritis research & therapy》2013,15(5):R111
Introduction
We have previously reported that bacterial toxins, especially endotoxins such as lipopolysaccharides (LPS), might be important causative agents in the pathogenesis of rheumatoid arthritis (RA) in an in vitro model that simulates the potential effects of residing in damp buildings. Since numerous inflammatory processes are linked with the nuclear factor-κB (NF-κB), we investigated in detail the effects of LPS on the NF-κB pathway and the postulated formation of procollagen-endotoxin complexes.Methods
An in vitro model of human chondrocytes was used to investigate LPS-mediated inflammatory signaling.Results
Immunoelectron microscopy revealed that LPS physically interact with collagen type II in the extracellular matrix (ECM) and anti-collagen type II significantly reduced this interaction. BMS-345541 (a specific inhibitor of IκB kinase (IKK)) or wortmannin (a specific inhibitor of phosphatidylinositol 3-kinase (PI-3K)) inhibited the LPS-induced degradation of the ECM and apoptosis in chondrocytes. This effect was completely inhibited by combining BMS-345541 and wortmannin. Furthermore, BMS-345541 and/or wortmannin suppressed the LPS-induced upregulation of catabolic enzymes that mediate ECM degradation (matrix metalloproteinases-9, -13), cyclooxygenase-2 and apoptosis (activated caspase-3). These proteins are regulated by NF-κB, suggesting that the NF-κB and PI-3K pathways are involved in LPS-induced cartilage degradation. The induction of NF-κB correlated with activation of IκBα kinase, IκBα phosphorylation, IκBα degradation, p65 phosphorylation and p65 nuclear translocation. Further upstream, LPS induced the expression of Toll-like receptor 4 (TLR4) and bound with TLR4, indicating that LPS acts through TLR4.Conclusion
These results suggest that molecular associations between LPS/TLR4/collagen type II in chondrocytes upregulate the NF-κB and PI-3K signaling pathways and activate proinflammatory activity. 相似文献4.
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6.
Gabrielle S. Prendergast Constanze M. Zurn A. Valeria Bers Ritchie M. Head Lars J. Hansson Jeremy C. Thomason 《Biofouling》2013,29(6):449-459
Many marine invertebrate larvae respond behaviourally to environmental settlement cues, yet behaviours are often only inferred from settlement patterns or are limited to laboratory studies. The behaviour of wild cypris larvae of Semibalanus balanoides L. was filmed on settlement tiles in the field. Tiles were of five different textures with a nested treatment of crude conspecific adult extract (AE). The effects of texture and AE on eleven defined behaviours were analysed. Texture affected the gross and net exploratory distances, velocity, acceleration and time spent exploring. AE attracted more cyprids during the first minute of immersion and increased the time spent on surfaces. Relatively few arrivals that either travel far and fast, or exit the surface rapidly, may indicate a lower chance of settlement. An increase in time spent on a surface may increase the probability of being in contact with the surface when the sign stimulus to settle occurs. 相似文献
7.
Constanze Hartmann Fabienne Mayenzet Jean-Paul Larcinese Olivier P. Haefliger Andrea Buettner Christian Starkenmann 《Steroids》2013,78(2):156-160
A method was developed for the quantification of 5-α-androst-16-en-3-one in human breast milk based on application of a stable isotope dilution assay using 5α-androst-16-en-3-one-6, 6-d2. The procedure includes extraction of the human milk by hexane with subsequent clean-up of the obtained extract by gel permeation and silica gel column chromatography. The extracted samples were analyzed by gas chromatography–mass spectrometry. Using this method 5-α-androst-16-en-3-one could be identified and for the first time quantified in a concentration range of 26–155 ng/kg in human milk. 相似文献
8.
Constanze Nossol A. K. Diesing S. Kahlert S. Kersten J. Kluess S. Ponsuksili R. Hartig K. Wimmers S. Dänicke H. J. Rothkötter 《Mycotoxin Research》2013,29(4):245-254
The numerous pores in the basement membrane (BM) of the intestinal villi are essential for the communication of enterocytes with cells in the lamina propria, an important mechanism for the induction of intestinal immune responses. The intestinal epithelial barrier is affected by the mycotoxin deoxynivalenol (DON) from both the apical (luminal) and basolateral (serosal) side. The pig is the most susceptible species to the anorectic and immune-modulating effects of DON, which is most prevalent in crops. We analysed in pigs the effect of DON-contaminated feed on the composition and perforation of the BM and the presence of CD16+ cells or their dendrites in the epithelium. In addition to in vivo experiments, in vitro studies were carried out. Using microarray analyses, the effects of DON on IPEC-J2 cells were studied with the focus on the BM. Our in vivo results showed in the control pigs: (1) a significant increased pore number (p?≤?0.001) in the jejunum in comparison to ileum, (2) no difference in the pore size, and (3) comparable frequency of intraepithelial CD16+ cells/dendrites in the jejunum and ileum. There was a marked trend that DON feeding increases: (1) the pore number in jejunum, and (2) the number of CD16+ cells/dendrites in the epithelium (Tukey–Kramer; p?=?0.055 and p?=?0.067, respectively). The in vivo results were extended with microarray analyses of epithelial cell (IPEC-J2 cells). The down-regulation of genes like syndecan, fibulin 6 and BM-40 was observed. These proteins are important factors in the BM composition and in formation of pores. Our results provide evidence that already low basolateral concentrations of DON (50 ng/mL) influence the production of the BM protein laminin by epithelial cells. Thus, DON affects the composition of the BM. 相似文献
9.
Catherine A. Campos Joseph B. Gianino Barbara J. Bailey Mary E. Baluyut Constanze Wiek Helmut Hanenberg Harlan E. Shannon Karen E. Pollok Brandon L. Ashfeld 《Bioorganic & medicinal chemistry letters》2013,23(24):6874-6878
Using an innovative approach toward multiple carbon–carbon bond-formations that relies on the multifaceted catalytic properties of titanocene complexes we constructed a series of C1–C7 analogs of curcumin for evaluation as brain and peripheral nervous system anti-cancer agents. C2-Arylated analogs proved efficacious against neuroblastoma (SK-N-SH & SK-N-FI) and glioblastoma multiforme (U87MG) cell lines. Similar inhibitory activity was also evident in p53 knockdown U87MG GBM cells. Furthermore, lead compounds showed limited growth inhibition in vitro against normal primary human CD34+hematopoietic progenitor cells. Taken together, the present findings indicate that these curcumin analogs are viable lead compounds for the development of new central and peripheral nervous system cancer chemotherapeutics with the potential for little effects on normal hematopoietic progenitor cells. 相似文献
10.
Sylvia Richter Xenia Gorny Judith Machts Gusalija Behnisch Torsten Wüstenberg Maike C. Herbort Thomas F. Münte Constanze I. Seidenbecher Bj?rn H. Schott 《PloS one》2013,8(1)
Recent investigations addressing the role of the synaptic multiadaptor molecule AKAP5 in human emotion and behavior suggest that the AKAP5 Pro100Leu polymorphism (rs2230491) contributes to individual differences in affective control. Carriers of the less common Leu allele show a higher control of anger as indicated by behavioral measures and dACC brain response on emotional distracters when compared to Pro homozygotes. In the current fMRI study we used an emotional working memory task according to the n-back scheme with neutral and negative emotional faces as target stimuli. Pro homozygotes showed a performance advantage at the behavioral level and exhibited enhanced activation of the amygdala and fusiform face area during working memory for emotional faces. On the other hand, Leu carriers exhibited increased activation of the dACC during performance of the 2-back condition. Our results suggest that AKAP5 Pro100Leu effects on emotion processing might be task-dependent with Pro homozygotes showing lower control of emotional interference, but more efficient processing of task-relevant emotional stimuli. 相似文献