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531.
K G Lüning 《Mutation research》1969,8(3):573-580
532.
533.
Ansgar Brüning Alexander Burges 《Biochemical and biophysical research communications》2008,377(4):1309-1314
HIV protease inhibitors are currently being discussed to be useful as new and alternative anti-cancer agents, especially as second line treatments for chemo-resistant human cancer types. Among three clinically applied HIV protease inhibitors tested, we found a high efficacy of nelfinavir on ovarian cancer cells, accompanied by apoptosis (annexin binding) and necrosis (propidium iodide permeability). In vitro, at concentrations used to induce cell death in ovarian cancer cells, nelfinavir had no effect on the cellular viability of fibroblasts or peripheral blood mononuclear leukocytes. Nelfinavir sensitized ovarian cancer cells to treatment with an apoptosis-inducing TRAIL receptor antibody due to upregulation of the TRAIL receptor DR5 as shown by RT-PCR and FACScan analysis. We conclude that nelfinavir, an already approved drug, is a highly efficient agent against ovarian cancer cells and could sensitize ovarian cancer cells to TRAIL treatment, either therapeutically applied or endogenously produced by cells of the immune system. 相似文献
534.
Myat Su Yin Dominique J. Bicout Peter Haddawy Johannes Schning Yongjua Laosiritaworn Patiwat Sa-angchai 《PLoS neglected tropical diseases》2021,15(3)
Dengue is an emerging vector-borne viral disease across the world. The primary dengue mosquito vectors breed in containers with sufficient water and nutrition. Outdoor containers can be detected from geotagged images using state-of-the-art deep learning methods. In this study, we utilize such container information from street view images in developing a risk mapping model and determine the added value of including container information in predicting dengue risk. We developed seasonal-spatial models in which the target variable dengue incidence was explained using weather and container variable predictors. Linear mixed models with fixed and random effects are employed in our models to account for different characteristics of containers and weather variables. Using data from three provinces of Thailand between 2015 and 2018, the models are developed at the sub-district level resolution to facilitate the development of effective targeted intervention strategies. The performance of the models is evaluated with two baseline models: a classic linear model and a linear mixed model without container information. The performance evaluated with the correlation coefficients, R-squared, and AIC shows the proposed model with the container information outperforms both baseline models in all three provinces. Through sensitivity analysis, we investigate the containers that have a high impact on dengue risk. Our findings indicate that outdoor containers identified from street view images can be a useful data source in building effective dengue risk models and that the resulting models have potential in helping to target container elimination interventions. 相似文献
535.
César Augusto Brüning Marina Prigol Daniela A. Barancelli Cristina Wayne Nogueira Gilson Zeni 《Molecular and cellular biochemistry》2009,332(1-2):17-24
Toxicological and pharmacological studies demonstrated that the introduction of functional groups into the aromatic ring of diphenyl diselenide alter its effect. The aim of this study was to evaluate the in vitro effect of m-trifluoromethyl-diphenyl diselenide (m-CF3–C6H4Se)2, p-chloro-diphenyl diselenide (p-Cl–C6H4Se)2 and p-methoxyl-diphenyl diselenide (p-CH3O–C6H4Se)2 on δ-aminolevulinate dehydratase (δ-ALA-D) and Na+, K+-ATPase activities in rat brain homogenates. Diselenides inhibited δ-ALA-D activity (IC50 4–6 μM [concentration inhibiting 50%]), and dithiothreitol (DTT) restored the enzyme activity. ZnCl2 (100 μM) did not restore δ-ALA-D inhibition caused by (p-Cl–C6H4Se)2 and (m-CF3–C6H4Se)2. Na+, K+-ATPase activity was more sensitive to (p-Cl–C6H4Se)2 and (m-CF3–C6H4Se)2 (IC50 6 μM) than (p-CH3O–C6H4Se)2 and (PhSe)2 (IC50 45 and 31 μM, respectively). DTT restored the activity of Na+, K+-ATPase inhibited by diselenides. The effect of diselenides on Na+/K+-ATPase is dependent on their substitutions in the aromatic ring. The mechanism through which diselenides inhibit δ-ALA-D and Na+, K+-ATPase activities involves the oxidation of thiol groups. 相似文献
536.
K A Markosian G G Pogosian N A Pa?tian R M Nalbandian 《Biokhimii?a (Moscow, Russia)》1979,44(5):844-850
The effects of cyanide, thiocyanide, azide, nitrite, nitrate, ferricyanide, persulfate, sulfide and halogenides on the intensities of the EPR spectrum and the band of 825 nm of cardiac cutochrome oxidase were studied. It was shown that according to their action on the copper the anions may be classified into three groups: 1) anions inducing the reduction of the copper (CN-, CNS-, S2-) anions changing the environment of the copper (N3-, NO2-); 3) anions slightly interacting with the copper (NO3-, halogenides). The incubation of cytochrome oxidase with ferricyanide led to the formation of a free-radical component without causing any pronounced changes in the copper environment; however, treatment of the protein with persulfate was accompanied by an irreversible modification of the copper EPR spectrum. 相似文献
537.
538.
Reproductive interference in two ground-hopper species: testing hypotheses of coexistence in the field 总被引:2,自引:0,他引:2
Similar to resource competition, reproductive interference may hamper the coexistence of closely related species. Species that utilize similar signal channels during mate finding may face substantial fitness costs when they come into contact and demographic displacement of the inferior species (sexual exclusion) is a likely outcome of such interactions. The two ground‐hopper species Tetrix ceperoi and Tetrix subulata broadly overlap in their ranges and general habitat requirements, but rarely co‐occur on a local scale. Results from laboratory and field experiments suggest that this mosaic pattern of sympatry might be influenced by reproductive interference. Here, we examine the significance of sexual interactions for these species in the field and test hypotheses on mechanisms of coexistence. Our results show that heterospecific sexual interactions also occur under field conditions, but in contrast to the experiments T. ceperoi was not the inferior species. The number of male mating attempts of both species was strongly correlated with encounter frequencies. Males discriminated between the sexes but not between the species, suggesting an incomplete mate recognition system in both species. The analysis of microhabitat preferences and spatial distribution revealed that habitat partitioning is not a suitable mechanism of coexistence in this system. Instead, the costs of reproductive interference are substantially mitigated by different niche breadths leading to different degrees of aggregation. Despite a considerable niche overlap T. ceperoi displayed a stronger preference for bare ground and occurred more aggregated than T. subulata, which had a broader niche. These differences may reduce the frequencies of heterospecific encounters and interactions in the field. Our results demonstrate that coexistence in the presence of reproductive interference is comparable to resource competition, being strongly influenced by ecological traits of the involved species, such as niche breadth and dispersion pattern. 相似文献
539.
540.
Beatriz Serrano-Solano Melanie C. Fll Cristbal Gallardo-Alba Anika Erxleben Helena Rasche Saskia Hiltemann Matthias Fahrner Mark J. Dunning Marcel H. Schulz Beta Scholtz Dave Clements Anton Nekrutenko Brnice Batut Bjrn A. Grüning 《PLoS computational biology》2021,17(5)
The COVID-19 pandemic is shifting teaching to an online setting all over the world. The Galaxy framework facilitates the online learning process and makes it accessible by providing a library of high-quality community-curated training materials, enabling easy access to data and tools, and facilitates sharing achievements and progress between students and instructors. By combining Galaxy with robust communication channels, effective instruction can be designed inclusively, regardless of the students’ environments. 相似文献