Search results for "X-RAY"
showing 10 items of 4234 documents
Advanced Techniques of Micro-Analysis and Confocal Microscopy: Perspectives for Studying Chemical and Structural Changes at the Interface Between Res…
1995
Migration of trace amounts of elements and structural changes characterize the interface between immiscible substances. The contact zone among filling materials, saliva, and the cavity wall has the additional function of preventing the progress of leakage and subsequent caries. Difficulties in chemically and structurally analyzing the gradients of composition in an interface of microscopic dimensions characterize the experimental situation. The use of advanced techniques of instrumental micro-analysis and techniques of micro-visualization is our approach to the problem. With confocal laser scanning microscopy (CLSM), effects of the components of the filling material on the structure of the…
Post-tilleyite, a dense calcium silicate-carbonate phase
2019
Scientific reports 9(1), 7898 (2019). doi:10.1038/s41598-019-44326-9
Emerging switchable ultraviolet photoluminescence in dehydrated Zn/Al layered double hydroxide nanoplatelets
2019
AbstractLayered double hydroxides show intriguing physical and chemical properties arising by their intrinsic self-assembled stacking of molecular-thick 2D nanosheets, enhanced active surface area, hosting of guest species by intercalation and anion exchanging capabilities. Here, we report on the unprecedented emerging intense ultraviolet photoluminescence in Zn/Al layered double hydroxide high-aspect-ratio nanoplatelets, which we discovered to be fully activated by drying under vacuum condition and thermal desorption as well. Photoluminescence and its quenching were reproducibly switched by a dehydration–hydration process. Photoluminescence properties were comprehensively evaluated, such a…
Revisiting the pH-gated conformational switch on the activities of HisKA-family histidine kinases
2020
13 páginas, 6 figuras, 3 tablas
On the (un)coupling of the chromophore, tongue interactions, and overall conformation in a bacterial phytochrome
2018
Phytochromes are photoreceptors in plants, fungi, and various microorganisms and cycle between metastable red light-absorbing (Pr) and far-red light-absorbing (Pfr) states. Their light responses are thought to follow a conserved structural mechanism that is triggered by isomerization of the chromophore. Downstream structural changes involve refolding of the so-called tongue extension of the phytochrome-specific GAF-related (PHY) domain of the photoreceptor. The tongue is connected to the chromophore by conserved DIP and PRXSF motifs and a conserved tyrosine, but the role of these residues in signal transduction is not clear. Here, we examine the tongue interactions and their interplay with …
Incorporation of mRNA in Lamellar Lipid Matrices for Parenteral Administration
2018
Molecular pharmaceutics 15(2), 642 - 651 (2018). doi:10.1021/acs.molpharmaceut.7b01022
rbFOX1/MBNL1 competition for CCUG RNA repeats binding contributes to myotonic dystrophy type 1/type 2 differences
2018
Myotonic dystrophy type 1 and type 2 (DM1, DM2) are caused by expansions of CTG and CCTG repeats, respectively. RNAs containing expanded CUG or CCUG repeats interfere with the metabolism of other RNAs through titration of the Muscleblind-like (MBNL) RNA binding proteins. DM2 follows a more favorable clinical course than DM1, suggesting that specific modifiers may modulate DM severity. Here, we report that the rbFOX1 RNA binding protein binds to expanded CCUG RNA repeats, but not to expanded CUG RNA repeats. Interestingly, rbFOX1 competes with MBNL1 for binding to CCUG expanded repeats and overexpression of rbFOX1 partly releases MBNL1 from sequestration within CCUG RNA foci in DM2 muscle ce…
Structure of AP205 Coat Protein Reveals Circular Permutation in ssRNA Bacteriophages.
2016
We are thankful to the MAX-lab staff for their support during our visit at the synchrotron.; International audience; AP205 is a single-stranded RNA bacteriophage that has a coat protein sequence not similar to any other known single-stranded RNA phage. Here, we report an atomic-resolution model of the AP205 virus-like particle based on a crystal structure of an unassembled coat protein dimer and a cryo-electron microscopy reconstruction of the assembled particle, together with secondary structure information from site-specific solid-state NMR data. The AP205 coat protein dimer adopts the conserved Leviviridae coat protein fold except for the N-terminal region, which forms a beta-hairpin in …
Conformational dynamism for DNA interaction in the Salmonella RcsB response regulator
2017
17 páginas, 7 figuras, 1 tabla
Dental pulp calcifications in prehistoric and historical skeletal remains
2020
Abstract Background The prevalence of hard tissue formations in the dental pulp varies considerably. Beside ageing processes and irritations of the dental pulp, etiological associations with cardiovascular disease and dietary habits have been discussed, which are of particular research interest. The aim of this pilot study is to provide new insights on structural and etiological factors involved in the development of pulp calcifications by investigating skeletal remains from different (pre)historic periods. Methods The jaws of 46 skeletons excavated in central Germany, were examined for the presence of pulp stones using digital volume tomography (DVT). A total of 1122 teeth were examined wi…