10 research outputs found
Bystanders in Bosnia and Herzegovina during the Conflict in the 1990s
Research on the Holocaust introduced the concept of bystander in order to describe
the civilian population passively tolerating atrocities committed against
the Jewish population, which was actively encouraged by the German national
socialist propaganda. Subsequently, a more general approach to this
concept has been employed to integrate it in a wider range of armed conflicts.
This article discusses the applicability of the bystander concept in the context
of the conflict in Bosnia and Herzegovina during the 1990s. In our case
study, the media, in particular in the United States, ascribed the role of the bystander
to the U.S. government, thus calling for its military action. Based on
witness accounts, as well as reports from legal records from the International
Crime Tribunal for Yugoslavia and other sources, the author emphasizes
key differences in the constellation of the conflict between the Holocaust and
the conflict in Bosnia and Herzegovina. Propaganda by the local media first
cast individuals in ethnic terms, and then actively mobilized the population to
take active roles in the conflict. Moreover, systematic traumatization was a
commonly used means to further polarize the civilian population along ethnic
lines, eliminating any space for passive observers. Thus, the applicability of
the concept of bystander on the local population in Bosnia and Herzegovina
is called into question
Controlling the interaction between CaMKII and Calmodulin with a photocrosslinking unnatural amino acid
Using unnatural amino acid mutagenesis, we made a mutant of CaMKII that forms a covalent linkage to Calmodulin upon illumination by UV light. Like wildātype CaMKII, the L308BzF mutant stoichiometrically binds to Calmodulin, in a calciumādependent manner. Using this construct, we demonstrate that Calmodulin binding to CaMKII, even under these stochiometric conditions, does not perturb the CaMKII oligomeric state. Furthermore, we were able to achieve activation of CaMKII L308BzF by UVāinduced binding of Calmodulin, which, once established, is further insensitive to calcium depletion. In addition to the canonical autoāinhibitory role of the regulatory segment, interāsubunit crosslinking in the absence of CaM indicates that kinase domains and regulatory segments are substantially mobile in basal conditions. Characterization of CaMKIIL308BzF in vitro, and its expression in mammalian cells, suggests it could be a promising candidate for control of CaMKII activity in mammalian cells with light.Peer Reviewe
Structural studies of the shortest extended synaptotagmin with only two C2 domains from Trypanosoma brucei
Alliance franƧaise contre les maladies parasitaire
Antioxidant and Antiproliferative Activities of Kale (<i>Brassica oleracea</i> L. Var. <i>acephala</i> DC.) and Wild Cabbage (<i>Brassica incana</i> Ten.) Polyphenolic Extracts
Brassicaceae are rich in healthy phytochemicals that have a positive impact on human health. The aim of this study was to analyze the phenolic compounds and antioxidant and anticancer potential of traditional Croatian kale (Brassica oleracea L. var. acephala DC.) and wild cabbage (Brassica incana Ten.) extracts. The phenolic groups and antioxidant activity were determined by spectrophotometry, selected phenolic compounds (ferulic acid, sinapic acid, salicylic acid, kaempferol, and quercetin) were analyzed by LC-MS/MS, and anticancer potential was evaluated in vitro using HeLa cells. The extracts of both plant species are rich in phenolic compounds and showed significant antioxidant activity at similar levels. LC-MS/MS detected sinapic acid as the most abundant phenolic acid, followed by ferulic acid, while salicylic acid was present at lower concentrations. A comparative analysis showed that wild cabbage contained significantly more sinapic acid, while kale contained more kaempferol and quercetin. Both Brassica extracts at a concentration of 50 Āµg mLā1 showed an antiproliferative effect on HeLa cells, while they did not affect the proliferation of normal human skin fibroblasts. Wild cabbage extract also showed an antiproliferative effect on HeLa cells at a lower applied concentration of 10 Āµg mLā1 of extracts. The clonogenic analysis also revealed the inhibitory effect of the extracts on HeLa colony growth
CaMKII autophosphorylation can occur between holoenzymes without subunit exchange
The article processing charge was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) ā 491192747 and the Open Access Publication Fund of Humboldt-UniversitƤt zu Berlin.The dodecameric protein kinase CaMKII is expressed throughout the body. The alpha isoform is responsible for synaptic plasticity and participates in memory through its phosphorylation of synaptic proteins. Its elaborate subunit organization and propensity for autophosphorylation allow it to preserve neuronal plasticity across space and time. The prevailing hypothesis for the spread of CaMKII activity, involving shuffling of subunits between activated and naive holoenzymes, is broadly termed subunit exchange. In contrast to the expectations of previous work, we found little evidence for subunit exchange upon activation, and no effect of restraining subunits to their parent holoenzymes. Rather, mass photometry, crosslinking mass spectrometry, single molecule TIRF microscopy and biochemical assays identify inter-holoenzyme phosphorylation (IHP) as the mechanism for spreading phosphorylation. The transient, activity-dependent formation of groups of holoenzymes is well suited to the speed of neuronal activity. Our results place fundamental limits on the activation mechanism of this kinase.Peer Reviewe