Alves, Frauke

[["dc.bibliographiccitation.firstpage","70"],["dc.bibliographiccitation.journal","NeuroImage"],["dc.bibliographiccitation.lastpage","80"],["dc.bibliographiccitation.volume","199"],["dc.contributor.author","Töpperwien, Mareike"],["dc.contributor.author","Markus, Andrea"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2020-03-04T13:32:26Z"],["dc.date.available","2020-03-04T13:32:26Z"],["dc.date.issued","2019"],["dc.description.abstract","Knowledge of the three-dimensional (3d) neuronal cytoarchitecture is an important factor in order to understand the connection between tissue structure and function or to visualize pathological changes in neurodegenerative diseases or tumor development. The gold standard in neuropathology is histology, a technique which provides insights into the cellular organization based on sectioning of the sample. Conventional histology, however, misses the complete 3d information as only individual two-dimensional slices through the object are available. In this work, we use propagation-based phase-contrast x-ray tomography to perform 3d virtual histology on cerebellar tissue from mice. This technique enables us to non-invasively visualize the entire 3d density distribution of the examined samples at isotropic (sub-)cellular resolution. One central challenge, however, of the technique is the fact that contrast for important structural features can be easily lost due to small electron density differences, notably between the cells and surrounding tissue. Here, we evaluate the influence of different embedding media, which are intermediate steps in sample preparation for classical histology, on contrast formation and examine the applicability of the different sample preparations both at a synchrotron-based holotomography setup as well as a laboratory source."],["dc.identifier.doi","10.1016/j.neuroimage.2019.05.043"],["dc.identifier.pmid","31129306"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16568"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63105"],["dc.identifier.url","https://mbexc.uni-goettingen.de/literature/publications/201"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation","EXC 2067: Multiscale Bioimaging"],["dc.relation.eissn","1095-9572"],["dc.relation.issn","1053-8119"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.relation.workinggroup","RG Alves (Translationale Molekulare Bildgebung)"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Contrast enhancement for visualizing neuronal cytoarchitecture by propagation-based x-ray phase-contrast tomography"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Scientific Reports"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Nicolas, Jan-David"],["dc.contributor.author","Khan, Amara"],["dc.contributor.author","Markus, Andrea"],["dc.contributor.author","Mohamed, Belal A."],["dc.contributor.author","Toischer, Karl"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2021-04-14T08:31:46Z"],["dc.date.available","2021-04-14T08:31:46Z"],["dc.date.issued","2020"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.1038/s41598-020-76163-6"],["dc.identifier.pmid","33168890"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/17813"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/83706"],["dc.identifier.url","https://mbexc.uni-goettingen.de/literature/publications/102"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.notes.intern","Merged from goescholar"],["dc.relation","EXC 2067: Multiscale Bioimaging"],["dc.relation.eissn","2045-2322"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.relation.workinggroup","RG Alves (Translationale Molekulare Bildgebung)"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","biomedical tomography"],["dc.title","X-ray diffraction and second harmonic imaging reveal new insights into structural alterations caused by pressure-overload in murine hearts"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","143"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","155"],["dc.bibliographiccitation.volume","22"],["dc.contributor.author","Dullin, Christian"],["dc.contributor.author","dal Monego, Simeone"],["dc.contributor.author","Larsson, Emanuel"],["dc.contributor.author","Mohammadi, Sara"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Garrovo, Chiara"],["dc.contributor.author","Biffi, Stefania"],["dc.contributor.author","Lorenzon, Andrea"],["dc.contributor.author","Markus, Andrea"],["dc.contributor.author","Napp, Joanna"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","Accardo, Agostino"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Tromba, Giuliana"],["dc.date.accessioned","2017-09-07T11:44:46Z"],["dc.date.available","2017-09-07T11:44:46Z"],["dc.date.issued","2015"],["dc.description.abstract","Functionalized computed tomography (CT) in combination with labelled cells is virtually non-existent due to the limited sensitivity of X-ray-absorption-based imaging, but would be highly desirable to realise cell tracking studies in entire organisms. In this study we applied in-line free propagation X-ray phase-contrast CT (XPCT) in an allergic asthma mouse model to assess structural changes as well as the biodistribution of barium-labelled macrophages in lung tissue. Alveolar macrophages that were barium-sulfate-loaded and fluorescent-labelled were instilled intratracheally into asthmatic and control mice. Mice were sacrificed after 24 h, lungs were kept in situ, inflated with air and scanned utilizing XPCT at the SYRMEP beamline (Elettra Synchrotron Light Source, Italy). Single-distance phase retrieval was used to generate data sets with ten times greater contrast-to-noise ratio than absorption-based CT (in our setup), thus allowing to depict and quantify structural hallmarks of asthmatic lungs such as reduced air volume, obstruction of airways and increased soft-tissue content. Furthermore, we found a higher concentration as well as a specific accumulation of the barium-labelled macrophages in asthmatic lung tissue. It is believe that XPCT will be beneficial in preclinical asthma research for both the assessment of therapeutic response as well as the analysis of the role of the recruitment of macrophages to inflammatory sites."],["dc.identifier.doi","10.1107/S1600577514021730"],["dc.identifier.fs","608140"],["dc.identifier.gro","3141991"],["dc.identifier.isi","000346850200022"],["dc.identifier.pmid","25537601"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/11558"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/3334"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.intern","Merged from goescholar"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation","info:eu-repo/grantAgreement/EC/FP7/230739/EU//P3AGI"],["dc.relation.eissn","1600-5775"],["dc.relation.issn","0909-0495"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Functionalized synchrotron in-line phase-contrast computed tomography: a novel approach for simultaneous quantification of structural alterations and localization of barium-labelled alveolar macrophages within mouse lung samples"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","151"],["dc.bibliographiccitation.journal","Progress in Biophysics and Molecular Biology"],["dc.bibliographiccitation.lastpage","165"],["dc.bibliographiccitation.volume","144"],["dc.contributor.author","Nicolas, Jan-David"],["dc.contributor.author","Bernhardt, Marten"],["dc.contributor.author","Schlick, Susanne F."],["dc.contributor.author","Tiburcy, Malte"],["dc.contributor.author","Zimmermann, Wolfram-Hubertus"],["dc.contributor.author","Khan, Amara"],["dc.contributor.author","Markus, Andrea"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Toischer, Karl"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2020-03-04T13:36:29Z"],["dc.date.available","2020-03-04T13:36:29Z"],["dc.date.issued","2019"],["dc.description.abstract","With the development of advanced focusing optics for x-rays, we can now use x-ray beams with spot sizes in the micro- or nanometer range to scan cells and large areas of tissues and continuously record the diffraction signals. From this data, x-ray scattering maps or so-called x-ray darkfield images are computed showing how different types of cells or regions of tissues differ in their diffraction intensity. At the same time a diffraction pattern is available for each scan point which encodes the local nanostructure, averaged over many contributing constituents illuminated by the beam. In this work we have exploited these new capabilities of scanning x-ray diffraction to investigate cardiac muscle cells as well as cardiac tissue. We give examples of how cardiac cells, especially living, cultured cells, can be prepared to be compatible with the instrumentation constraints of nano- or micro-diffraction instruments. Furthermore, we show how the developmental stage, ranging from neonatal to adult cells, as well as the final preparation state of the cardiomyocytes influences the recorded scattering signal and how these diffraction signals compare to the structure of a fully developed cardiac muscle."],["dc.identifier.doi","10.1016/j.pbiomolbio.2018.05.012"],["dc.identifier.pmid","29914693"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63107"],["dc.language.iso","en"],["dc.relation.eissn","1873-1732"],["dc.relation.issn","0079-6107"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY-NC-ND 4.0"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.title","X-ray diffraction imaging of cardiac cells and tissue"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","035007"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","AIP Advances"],["dc.bibliographiccitation.volume","6"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Toepperwien, Mareike"],["dc.contributor.author","Dullin, Christian"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-09-07T11:54:36Z"],["dc.date.available","2017-09-07T11:54:36Z"],["dc.date.issued","2016"],["dc.description.abstract","We have performed high-resolution phase-contrast tomography on whole mice with a laboratory setup. Enabled by a high-brilliance liquid- metal- jet source, we show the feasibility of propagation-based phase contrast in local tomography even in the presence of strongly absorbing surrounding tissue as it is the case in small animal imaging of the lung. We demonstrate the technique by reconstructions of the mouse lung for two different fields of view, covering the whole organ, and a zoom to the local finer structure of terminal airways and alveoli. With a resolution of a few micrometers and the wide availability of the technique, studies of larger biological samples at the cellular level become possible. (c) 2016 Author(s)."],["dc.identifier.doi","10.1063/1.4943898"],["dc.identifier.gro","3141718"],["dc.identifier.isi","000373684200008"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/13246"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/302"],["dc.notes.intern","WoS Import 2017-03-10 / Funder: BMBF-Verbundforschung; [SFB 755]"],["dc.notes.intern","Merged from goescholar"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","2158-3226"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Propagation-based phase-contrast tomography for high-resolution lung imaging with laboratory sources"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","4"],["dc.contributor.author","Nicolas, J. D."],["dc.contributor.author","Markus, Marietta Andrea"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Frohn, Jasper"],["dc.contributor.author","Reichardt, Marius"],["dc.contributor.author","Töpperwien, Mareike"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.editor","Wang, Geng"],["dc.contributor.editor","Müller-Myhsok, Bertram"],["dc.date.accessioned","2020-06-26T10:11:47Z"],["dc.date.available","2020-06-26T10:11:47Z"],["dc.date.issued","2017"],["dc.description.abstract","In this work we present x-ray phase-contrast tomography of heart tissue from mouse, combining computed tomography (CT) scans with laboratory and synchrotron radiation. The work serves as a proof-of-concept that the cyto-architecture and in particular the myofibril orientation can be assessed in three dimensions (3D) by phase-contrast CT. We demonstrate the synergistic use of laboratory μ -CT and of the high resolution synchrotron setup based on waveguide optics. Details on preparation, instrumentation and analysis are given, as a state of the art reference for heart tissue tomography, and as a starting point for further progress."],["dc.identifier.doi","10.1117/12.2276648"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/66750"],["dc.language.iso","en"],["dc.notes.preprint","yes"],["dc.relation.eventend","2017-09-25"],["dc.relation.eventlocation","San Diego"],["dc.relation.eventstart","2017-09-25"],["dc.relation.isbn","9781510612396"],["dc.relation.isbn","9781510612402"],["dc.relation.iserratumof","yes"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray optics"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Nanoscale holographic tomography of heart tissue with x-ray waveguide optics"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","282"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Acta Crystallographica Section A Foundations and Advances"],["dc.bibliographiccitation.lastpage","292"],["dc.bibliographiccitation.volume","73"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Toepperwien, Mareike"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2022-03-01T11:47:06Z"],["dc.date.available","2022-03-01T11:47:06Z"],["dc.date.issued","2017"],["dc.description.abstract","X-ray tomography at the level of single biological cells is possible in a low-dose regime, based on full-field holographic recordings, with phase contrast originating from free-space wave propagation. Building upon recent progress in cellular imaging based on the illumination by quasi-point sources provided by X-ray waveguides, here this approach is extended in several ways. First, the phase-retrieval algorithms are extended by an optimized deterministic inversion, based on a multi-distance recording. Second, different advanced forms of iterative phase retrieval are used, operational for single-distance and multi-distance recordings. Results are compared for several different preparations of macrophage cells, for different staining and labelling. As a result, it is shown that phase retrieval is no longer a bottleneck for holographic imaging of cells, and how advanced schemes can be implemented to cope also with high noise and inconsistencies in the data."],["dc.description.abstract","X-ray tomography at the level of single biological cells is possible in a low-dose regime, based on full-field holographic recordings, with phase contrast originating from free-space wave propagation. Building upon recent progress in cellular imaging based on the illumination by quasi-point sources provided by X-ray waveguides, here this approach is extended in several ways. First, the phase-retrieval algorithms are extended by an optimized deterministic inversion, based on a multi-distance recording. Second, different advanced forms of iterative phase retrieval are used, operational for single-distance and multi-distance recordings. Results are compared for several different preparations of macrophage cells, for different staining and labelling. As a result, it is shown that phase retrieval is no longer a bottleneck for holographic imaging of cells, and how advanced schemes can be implemented to cope also with high noise and inconsistencies in the data."],["dc.identifier.doi","10.1107/S2053273317007902"],["dc.identifier.doi","10.1107/s2053273317007902"],["dc.identifier.gro","3142469"],["dc.identifier.pii","S2053273317007902"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/103911"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-531"],["dc.notes.status","final"],["dc.relation.eissn","2053-2733"],["dc.relation.issn","2053-2733"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights.uri","http://creativecommons.org/licenses/by/2.0/uk/legalcode"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Three-dimensional single-cell imaging with X-ray waveguides in the holographic regime"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","09973"],["dc.bibliographiccitation.journal","Scientific Reports"],["dc.bibliographiccitation.volume","5"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Markus, Andrea"],["dc.contributor.author","Bartels, Matthias"],["dc.contributor.author","Dullin, Christian"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-09-07T11:44:24Z"],["dc.date.available","2017-09-07T11:44:24Z"],["dc.date.issued","2015"],["dc.description.abstract","We have performed x-ray phase-contrast tomography on mouse lung tissue. Using a divergent x-ray beam generated by nanoscale focusing, we used zoom tomography to produce three-dimensional reconstructions with selectable magnification, resolution, and field of view. Thus, macroscopic tissue samples extending over several mm can be studied in sub-cellular-level structural detail. The zoom capability and, in particular, the high dose efficiency are enabled by the near-perfect exit wavefront of an optimized x-ray waveguide channel. In combination with suitable phase-retrieval algorithms, challenging radiation-sensitive and low-contrast samples can be reconstructed with minimal artefacts. The dose efficiency of the method is demonstrated by the reconstruction of living macrophages both with and without phagocytized contrast agents. We also used zoom tomography to visualize barium-labelled macrophages in the context of morphological structures in asthmatic and healthy mouse lung tissue one day after intratracheal application. The three-dimensional reconstructions showed that the macrophages predominantly localized to the alveoli, but they were also found in bronchial walls, indicating that these cells might be able to migrate from the lumen of the bronchi through the epithelium."],["dc.identifier.doi","10.1038/srep09973"],["dc.identifier.fs","615791"],["dc.identifier.gro","3141904"],["dc.identifier.isi","000354310200001"],["dc.identifier.pmid","25966338"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/13625"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/2367"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","2045-2322"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY 4.0"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.subject.mesh","Animals"],["dc.subject.mesh","Cell Line, Transformed"],["dc.subject.mesh","Cell Movement"],["dc.subject.mesh","Macrophages, Alveolar"],["dc.subject.mesh","Mice"],["dc.subject.mesh","Pulmonary Alveoli"],["dc.subject.mesh","Respiratory Mucosa"],["dc.subject.mesh","Tomography, X-Ray"],["dc.title","Phase-contrast zoom tomography reveals precise locations of macrophages in mouse lungs"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]