@article{KnoxBrownRindfleischGuentheretal.2020, author = {Knox-Brown, Patrick and Rindfleisch, Tobias and G{\"u}nther, Anne and Balow, Kim and Bremer, Anne and Walther, Dirk and Miettinen, Markus S. and Hincha, Dirk K. and Thalhammer, Anja}, title = {Similar Yet Different}, series = {International Journal of Molecular Sciences}, volume = {21}, journal = {International Journal of Molecular Sciences}, number = {8}, publisher = {Molecular Diversity Preservation International}, address = {Basel}, issn = {1422-0067}, doi = {10.3390/ijms21082794}, pages = {25}, year = {2020}, abstract = {The importance of intrinsically disordered late embryogenesis abundant (LEA) proteins in the tolerance to abiotic stresses involving cellular dehydration is undisputed. While structural transitions of LEA proteins in response to changes in water availability are commonly observed and several molecular functions have been suggested, a systematic, comprehensive and comparative study of possible underlying sequence-structure-function relationships is still lacking. We performed molecular dynamics (MD) simulations as well as spectroscopic and light scattering experiments to characterize six members of two distinct, lowly homologous clades of LEA_4 family proteins from Arabidopsis thaliana. We compared structural and functional characteristics to elucidate to what degree structure and function are encoded in LEA protein sequences and complemented these findings with physicochemical properties identified in a systematic bioinformatics study of the entire Arabidopsis thaliana LEA_4 family. Our results demonstrate that although the six experimentally characterized LEA_4 proteins have similar structural and functional characteristics, differences concerning their folding propensity and membrane stabilization capacity during a freeze/thaw cycle are obvious. These differences cannot be easily attributed to sequence conservation, simple physicochemical characteristics or the abundance of sequence motifs. Moreover, the folding propensity does not appear to be correlated with membrane stabilization capacity. Therefore, the refinement of LEA_4 structural and functional properties is likely encoded in specific patterns of their physicochemical characteristics.}, language = {en} } @article{MaaresKeilKozaetal.2018, author = {Maares, Maria and Keil, Claudia and Koza, Jenny and Straubing, Sophia and Schwerdtle, Tanja and Haase, Hajo}, title = {In Vitro Studies on Zinc Binding and Buffering by Intestinal Mucins}, series = {International Journal of Molecular Sciences}, volume = {19}, journal = {International Journal of Molecular Sciences}, number = {9}, issn = {1422-0067}, doi = {10.3390/ijms19092662}, pages = {20}, year = {2018}, abstract = {The investigation of luminal factors influencing zinc availability and accessibility in the intestine is of great interest when analyzing parameters regulating intestinal zinc resorption. Of note, intestinal mucins were suggested to play a beneficial role in the luminal availability of zinc. Their exact zinc binding properties, however, remain unknown and the impact of these glycoproteins on human intestinal zinc resorption has not been investigated in detail. Thus, the aim of this study is to elucidate the impact of intestinal mucins on luminal uptake of zinc into enterocytes and its transfer into the blood. In the present study, in vitro zinc binding properties of mucins were analyzed using commercially available porcine mucins and secreted mucins of the goblet cell line HT-29-MTX. The molecular zinc binding capacity and average zinc binding affinity of these glycoproteins demonstrates that mucins contain multiple zinc-binding sites with biologically relevant affinity within one mucin molecule. Zinc uptake into the enterocyte cell line Caco-2 was impaired by zinc-depleted mucins. Yet this does not represent their form in the intestinal lumen in vivo under zinc adequate conditions. In fact, zinc-uptake studies into enterocytes in the presence of mucins with differing degree of zinc saturation revealed zinc buffering by these glycoproteins, indicating that mucin-bound zinc is still available for the cells. Finally, the impact of mucins on zinc resorption using three-dimensional cultures was studied comparing the zinc transfer of a Caco-2/HT-29-MTX co-culture and conventional Caco-2 monoculture. Here, the mucin secreting co-cultures yielded higher fractional zinc resorption and elevated zinc transport rates, suggesting that intestinal mucins facilitate the zinc uptake into enterocytes and act as a zinc delivery system for the intestinal epithelium.}, language = {en} } @article{LonsdorfKlingelhoeferJensAndreattaetal.2019, author = {Lonsdorf, Tina B. and Klingelh{\"o}fer-Jens, Maren and Andreatta, Marta and Beckers, Tom and Chalkia, Anastasia and Gerlicher, Anna and Jentsch, Valerie L. and Drexler, Shira Meir and Mertens, Gaetan and Richter, Jan and Sjouwerman, Rachel and Wendt, Julia and Merz, Christian J.}, title = {Navigating the garden of forking paths for data exclusions in fear conditioning research}, series = {eLife}, volume = {8}, journal = {eLife}, publisher = {eLife Sciences Publications}, address = {Cambridge}, issn = {2050-084X}, doi = {10.7554/eLife.52465}, pages = {36}, year = {2019}, abstract = {In this report, we illustrate the considerable impact of researcher degrees of freedom with respect to exclusion of participants in paradigms with a learning element. We illustrate this empirically through case examples from human fear conditioning research, in which the exclusion of 'non-learners' and 'non-responders' is common - despite a lack of consensus on how to define these groups. We illustrate the substantial heterogeneity in exclusion criteria identified in a systematic literature search and highlight the potential problems and pitfalls of different definitions through case examples based on re-analyses of existing data sets. On the basis of these studies, we propose a consensus on evidence-based rather than idiosyncratic criteria, including clear guidelines on reporting details. Taken together, we illustrate how flexibility in data collection and analysis can be avoided, which will benefit the robustness and replicability of research findings and can be expected to be applicable to other fields of research that involve a learning element.}, language = {en} } @article{LonsdorfKlingelhoeferJensAndreattaetal.2019, author = {Lonsdorf, Tina B. and Klingelh{\"o}fer-Jens, Maren and Andreatta, Marta and Beckers, Tom and Chalkia, Anastasia and Gerlicher, Anna Maria Veronika and Jentsch, Valerie L. and Drexler, Shira Meir and Mertens, Gaetan and Richter, Jan and Sjouwerman, Rachel and Wendt, Julia and Merz, Christian J.}, title = {Navigating the garden of forking paths for data exclusions in fear conditioning research}, series = {eLife}, volume = {8}, journal = {eLife}, publisher = {eLife Sciences Publications}, address = {Cambridge}, issn = {2050-084X}, doi = {10.7554/eLife.52465}, pages = {36}, year = {2019}, language = {en} } @article{GuentherKlaussToroNahuelpanetal.2019, author = {G{\"u}nther, Erika and Klauß, Andr{\´e} and Toro-Nahuelpan, Mauricio and Sch{\"u}ler, Dirk and Hille, Carsten and Faivre, Damien}, title = {The in vivo mechanics of the magnetotactic backbone as revealed by correlative FLIM-FRET and STED microscopy}, series = {Scientific reports}, volume = {9}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-019-55804-5}, pages = {9}, year = {2019}, abstract = {Protein interaction and protein imaging strongly benefit from the advancements in time-resolved and superresolution fluorescence microscopic techniques. However, the techniques were typically applied separately and ex vivo because of technical challenges and the absence of suitable fluorescent protein pairs. Here, we show correlative in vivo fluorescence lifetime imaging microscopy Forster resonance energy transfer (FLIM-FRET) and stimulated emission depletion (STED) microscopy to unravel protein mechanics and structure in living cells. We use magnetotactic bacteria as a model system where two proteins, MamJ and MamK, are used to assemble magnetic particles called magnetosomes. The filament polymerizes out of MamK and the magnetosomes are connected via the linker MamJ. Our system reveals that bacterial filamentous structures are more fragile than the connection of biomineralized particles to this filament. More importantly, we anticipate the technique to find wide applicability for the study and quantification of biological processes in living cells and at high resolution.}, language = {en} } @article{ScholkmannSiemonBoometal.2017, author = {Scholkmann, Antonia and Siemon, Jens and Boom, Kay-Dennis and Knigge, Michel}, title = {Lernzeitnutzung im Planspielunterricht}, series = {Zeitschrift f{\"u}r Erziehungswissenschaft}, volume = {20}, journal = {Zeitschrift f{\"u}r Erziehungswissenschaft}, publisher = {Springer}, address = {Wiesbaden}, issn = {1434-663X}, doi = {10.1007/s11618-017-0736-4}, pages = {651 -- 669}, year = {2017}, abstract = {The effective use of learning time is considered one of the most important predictors of successful and good teaching. In the present study we investigated how cognitive skills and goal orientation influenced the effective use of learning time during the open phases of game-based learning We used a newly developed method for video- and audio analysis (German: MuVA), which allowed for reliable documentation of students' interactions during those phases. The two-step multiple regression model demonstrated that both the learner's and the learning partner's goal orientation explain significant parts of the variance: A high performance goal orientation impairs a student's effective use of learning time, while a high performance avoidance orientation has a positive impact on his or her effective use of learning time. Working with a partner who has a high learning goal orientation or a high work avoidance orientation increases a student's effective use of his or her learning time, while a high work avoidance orientation on the partner's side has the opposite effect. Cognitive skills did not influence the effective use of learning time.}, language = {de} } @article{ThomasCarvalhoHaileetal.2019, author = {Thomas, Jessica E. and Carvalho, Gary R. and Haile, James and Rawlence, Nicolas J. and Martin, Michael D. and Ho, Simon Y. W. and Sigfusson, Arnor P. and Josefsson, Vigfus A. and Frederiksen, Morten and Linnebjerg, Jannie F. and Castruita, Jose A. Samaniego and Niemann, Jonas and Sinding, Mikkel-Holger S. and Sandoval-Velasco, Marcela and Soares, Andre E. R. and Lacy, Robert and Barilaro, Christina and Best, Juila and Brandis, Dirk and Cavallo, Chiara and Elorza, Mikelo and Garrett, Kimball L. and Groot, Maaike and Johansson, Friederike and Lifjeld, Jan T. and Nilson, Goran and Serjeanston, Dale and Sweet, Paul and Fuller, Errol and Hufthammer, Anne Karin and Meldgaard, Morten and Fjeldsa, Jon and Shapiro, Beth and Hofreiter, Michael and Stewart, John R. and Gilbert, M. Thomas P. and Knapp, Michael}, title = {Demographic reconstruction from ancient DNA supports rapid extinction of the great auk}, series = {eLife}, volume = {8}, journal = {eLife}, publisher = {eLife Sciences Publications}, address = {Cambridge}, issn = {2050-084X}, doi = {10.7554/eLife.47509}, pages = {35}, year = {2019}, abstract = {The great auk was once abundant and distributed across the North Atlantic. It is now extinct, having been heavily exploited for its eggs, meat, and feathers. We investigated the impact of human hunting on its demise by integrating genetic data, GPS-based ocean current data, and analyses of population viability. We sequenced complete mitochondrial genomes of 41 individuals from across the species' geographic range and reconstructed population structure and population dynamics throughout the Holocene. Taken together, our data do not provide any evidence that great auks were at risk of extinction prior to the onset of intensive human hunting in the early 16th century. In addition, our population viability analyses reveal that even if the great auk had not been under threat by environmental change, human hunting alone could have been sufficient to cause its extinction. Our results emphasise the vulnerability of even abundant and widespread species to intense and localised exploitation.}, language = {en} } @article{LoepfeDussZafeiropoulouetal.2019, author = {L{\"o}pfe, Moira and Duss, Anja and Zafeiropoulou, Katerina-Alexandra and Bjoergvinsdottir, Oddny and Eglin, David and Fortunato, Giuseppino and Klasen, J{\"u}rgen and Ferguson, Stephen J. and W{\"u}rtz-Kozak, Karin and Krupkova, Olga}, title = {Electrospray-Based Microencapsulation of Epigallocatechin 3-Gallate for Local Delivery into the Intervertebral Disc}, series = {Pharmaceutics}, volume = {11}, journal = {Pharmaceutics}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {1999-4923}, doi = {10.3390/pharmaceutics11090435}, pages = {15}, year = {2019}, abstract = {Locally delivered anti-inflammatory compounds can restore the homeostasis of the degenerated intervertebral disc (IVD). With beneficial effects on IVD cells, epigallocatechin 3-gallate (EGCG) is a promising therapeutic candidate. However, EGCG is prone to rapid degradation and/or depletion. Therefore, the purpose of this study was to develop a method for controlled EGCG delivery in the degenerated IVD. Primary IVD cells were isolated from human donors undergoing IVD surgeries. EGCG was encapsulated into microparticles by electrospraying of glutaraldehyde-crosslinked gelatin. The resulting particles were characterized in terms of cytocompatibility and anti-inflammatory activity, and combined with a thermoresponsive carrier to produce an injectable EGCG delivery system. Subsequently, electrospraying was scaled up using the industrial NANOSPIDER (TM) technology. The produced EGCG microparticles reduced the expression of inflammatory (IL-6, IL-8, COX-2) and catabolic (MMP1, MMP3, MMP13) mediators in pro-inflammatory 3D cell cultures. Combining the EGCG microparticles with the carrier showed a trend towards modulating EGCG activity/release. Electrospray upscaling was achieved, leading to particles with homogenous spherical morphologies. In conclusion, electrospray-based encapsulation of EGCG resulted in cytocompatible microparticles that preserved the activity of EGCG and showed the potential to control EGCG release, thus favoring IVD health by downregulating local inflammation. Future studies will focus on further exploring the biological activity of the developed delivery system for potential clinical use.}, language = {en} } @article{RinaldiFormisanoKappeletal.2019, author = {Rinaldi, G. and Formisano, M. and Kappel, David and Capaccioni, F. and Bockelee-Morvan, D. and Cheng, Y-C and Vincent, J-B and Deshapriya, P. and Arnold, G. and Capria, M. T. and Ciarniello, M. and De Sanctis, M. C. and Doose, L. and Erard, S. and Federico, C. and Filacchione, G. and Fink, U. and Leyrat, C. and Longobardo, A. and Magni, G. and Mighorini, A. and Mottola, S. and Naletto, G. and Raponi, A. and Taylor, F. and Tosi, F. and Tozzi, G. P. and Salatti, M.}, title = {Analysis of night-side dust activity on comet 67P observed by VIRTIS-M}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {630}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201834907}, pages = {16}, year = {2019}, abstract = {On 2015 July 18, near perihelion at a heliocentric distance of 1.28 au, the Visible InfraRed Thermal Imaging Spectrometer (VIRTIS-M) on board the Rosetta spacecraft had the opportunity of observing dust activity in the inner coma with a view of the night side (shadowed side) of comet 67P/Churyumov-Gerasimenko. At the time of the measurements we present here, we observe a dust plume that originates on the far side of the nucleus. We are able to identify the approximate location of its source at the boundary between the Hapi and Anuket regions, and we find that it has been in darkness for some hours before the observation. Assuming that this time span is equal to the conductive time scale, we obtain a thermal inertia in the range 25-36 W K-1 m(-2) s(-1/2). These thermal inertia values can be used to verify with a 3D finite-element method (REM) numerical code whether the surface and subsurface temperatures agree with the values found in the literature. We explored three different configurations: (1) a layer of water ice mixed with dust beneath a dust mantle of 5 mm with thermal inertia of 36 J m(-2) K-1 S-0.5 ; (2) the same structure, but with thermal inertia of 100 J m(-2) K-1 S-0.5; (3) an ice-dust mixture that is directly exposed. Of these three configurations, the first seems to be the most reasonable, both for the low thermal inertia and for the agreement with the surface and subsurface temperatures that have been found for the comet 67P/Churyumov-Gerasimenko. The spectral properties of the plume show that the visible dust color ranged from 16 +/- 4.8\%/100 nm to 13 +/- 2.6\%/100 nm, indicating that this plume has no detectable color gradient. The morphology of the plume can be classified as a narrow jet that has an estimated total ejected mass of between 6 and 19 tons when we assume size distribution indices between -2.5 and -3.}, language = {en} } @article{TubianaRinaldiGuettleretal.2019, author = {Tubiana, C. and Rinaldi, G. and Guettler, C. and Snodgrass, C. and Shi, X. and Hu, X. and Marschall, R. and Fulle, M. and Bockeele-Morvan, D. and Naletto, G. and Capaccioni, F. and Sierks, H. and Arnold, G. and Barucci, M. A. and Bertaux, J-L and Bertini, I and Bodewits, D. and Capria, M. T. and Ciarniello, M. and Cremonese, G. and Crovisier, J. and Da Deppo, V and Debei, S. and De Cecco, M. and Deller, J. and De Sanctis, M. C. and Davidsson, B. and Doose, L. and Erard, S. and Filacchione, G. and Fink, U. and Formisano, M. and Fornasier, S. and Gutierrez, P. J. and Ip, W-H and Ivanovski, S. and Kappel, David and Keller, H. U. and Kolokolova, L. and Koschny, D. and Krueger, H. and La Forgia, F. and Lamy, P. L. and Lara, L. M. and Lazzarin, M. and Levasseur-Regourd, A. C. and Lin, Z-Y and Longobardo, A. and Lopez-Moreno, J. J. and Marzari, F. and Migliorini, A. and Mottola, S. and Rodrigo, R. and Taylor, F. and Toth, I and Zakharov, V}, title = {Diurnal variation of dust and gas production in comet 67P/Churyumov-Gerasimenko at the inbound equinox as seen by OSIRIS and VIRTIS-M on board Rosetta}, series = {Astronomy and astrophysics : an international weekly journal}, volume = {630}, journal = {Astronomy and astrophysics : an international weekly journal}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201834869}, pages = {14}, year = {2019}, abstract = {Context. On 27 April 2015, when comet 67P/Churyumov-Gerasimenko was at 1.76 au from the Sun and moving toward perihelion, the OSIRIS and VIRTIS-M instruments on board the Rosetta spacecraft simultaneously observed the evolving dust and gas coma during a complete rotation of the comet. Aims. We aim to characterize the spatial distribution of dust, H2O, and CO2 gas in the inner coma. To do this, we performed a quantitative analysis of the release of dust and gas and compared the observed H2O production rate with the rate we calculated using a thermophysical model. Methods. For this study we selected OSIRIS WAC images at 612 nm (dust) and VIRTIS-M image cubes at 612 nm, 2700 nm (H2O emission band), and 4200 nm (CO2 emission band). We measured the average signal in a circular annulus to study the spatial variation around the comet, and in a sector of the annulus to study temporal variation in the sunward direction with comet rotation, both at a fixed distance of 3.1 km from the comet center. Results. The spatial correlation between dust and water, both coming from the sunlit side of the comet, shows that water is the main driver of dust activity in this time period. The spatial distribution of CO2 is not correlated with water and dust. There is no strong temporal correlation between the dust brightness and water production rate as the comet rotates. The dust brightness shows a peak at 0 degrees subsolar longitude, which is not pronounced in the water production. At the same epoch, there is also a maximum in CO2 production. An excess of measured water production with respect to the value calculated using a simple thermophysical model is observed when the head lobe and regions of the southern hemisphere with strong seasonal variations are illuminated (subsolar longitude 270 degrees-50 degrees). A drastic decrease in dust production when the water production (both measured and from the model) displays a maximum occurs when typical northern consolidated regions are illuminated and the southern hemisphere regions with strong seasonal variations are instead in shadow (subsolar longitude 50 degrees-90 degrees). Possible explanations of these observations are presented and discussed.}, language = {en} }