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  1. Article ; Online: Toward on-the-fly trajectory optimization for C-arm CBCT under strong kinematic constraints.

    Hatamikia, Sepideh / Biguri, Ander / Kronreif, Gernot / Figl, Michael / Russ, Tom / Kettenbach, Joachim / Buschmann, Martin / Birkfellner, Wolfgang

    PloS one

    2021  Volume 16, Issue 2, Page(s) e0245508

    Abstract: ... trajectories could achieve a comparable image quality in the VOI compared to the standard C-arm circular CBCT ... from the optimized trajectories and the standard C-arm CBCT for all three targets. The whole trajectory optimization ...

    Abstract Cone beam computed tomography (CBCT) has become a vital tool in interventional radiology. Usually, a circular source-detector trajectory is used to acquire a three-dimensional (3D) image. Kinematic constraints due to the patient size or additional medical equipment often cause collisions with the imager while performing a full circular rotation. In a previous study, we developed a framework to design collision-free, patient-specific trajectories for the cases in which circular CBCT is not feasible. Our proposed trajectories included enough information to appropriately reconstruct a particular volume of interest (VOI), but the constraints had to be defined before the intervention. As most collisions are unpredictable, performing an on-the-fly trajectory optimization is desirable. In this study, we propose a search strategy that explores a set of trajectories that cover the whole collision-free area and subsequently performs a search locally in the areas with the highest image quality. Selecting the best trajectories is performed using simulations on a prior diagnostic CT volume which serves as a digital phantom for simulations. In our simulations, the Feature SIMilarity Index (FSIM) is used as the objective function to evaluate the imaging quality provided by different trajectories. We investigated the performance of our methods using three different anatomical targets inside the Alderson-Rando phantom. We used FSIM and Universal Quality Image (UQI) to evaluate the final reconstruction results. Our experiments showed that our proposed trajectories could achieve a comparable image quality in the VOI compared to the standard C-arm circular CBCT. We achieved a relative deviation less than 10% for both FSIM and UQI metrics between the reconstructed images from the optimized trajectories and the standard C-arm CBCT for all three targets. The whole trajectory optimization took approximately three to four minutes.
    MeSH term(s) Algorithms ; Cone-Beam Computed Tomography/instrumentation ; Cone-Beam Computed Tomography/methods ; Humans ; Image Processing, Computer-Assisted/methods ; Phantoms, Imaging
    Language English
    Publishing date 2021-02-09
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0245508
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Thesis: K ATP -Kanäle-Bindung von Nukletoiden an den C-Terminus der K IR -Untereinheit, Einfluss des pH-Wertes und Prädiktion der sekundären Proteinstruktur

    Buschmann, Alexandra S.

    2006  

    Author's details von Alexandra S. Buschmann
    Language German
    Size X, 125 Bl. : graph. Darst.
    Edition [Mikrofiche-Ausg.]
    Publishing country Germany
    Document type Book ; Thesis
    Thesis / German Habilitation thesis Berlin, Freie Univ., Diss., 2006
    HBZ-ID HT014830149
    Database Catalogue ZB MED Medicine, Health

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  3. Article ; Online: Toward on-the-fly trajectory optimization for C-arm CBCT under strong kinematic constraints.

    Sepideh Hatamikia / Ander Biguri / Gernot Kronreif / Michael Figl / Tom Russ / Joachim Kettenbach / Martin Buschmann / Wolfgang Birkfellner

    PLoS ONE, Vol 16, Iss 2, p e

    2021  Volume 0245508

    Abstract: ... trajectories could achieve a comparable image quality in the VOI compared to the standard C-arm circular CBCT ... from the optimized trajectories and the standard C-arm CBCT for all three targets. The whole trajectory optimization ...

    Abstract Cone beam computed tomography (CBCT) has become a vital tool in interventional radiology. Usually, a circular source-detector trajectory is used to acquire a three-dimensional (3D) image. Kinematic constraints due to the patient size or additional medical equipment often cause collisions with the imager while performing a full circular rotation. In a previous study, we developed a framework to design collision-free, patient-specific trajectories for the cases in which circular CBCT is not feasible. Our proposed trajectories included enough information to appropriately reconstruct a particular volume of interest (VOI), but the constraints had to be defined before the intervention. As most collisions are unpredictable, performing an on-the-fly trajectory optimization is desirable. In this study, we propose a search strategy that explores a set of trajectories that cover the whole collision-free area and subsequently performs a search locally in the areas with the highest image quality. Selecting the best trajectories is performed using simulations on a prior diagnostic CT volume which serves as a digital phantom for simulations. In our simulations, the Feature SIMilarity Index (FSIM) is used as the objective function to evaluate the imaging quality provided by different trajectories. We investigated the performance of our methods using three different anatomical targets inside the Alderson-Rando phantom. We used FSIM and Universal Quality Image (UQI) to evaluate the final reconstruction results. Our experiments showed that our proposed trajectories could achieve a comparable image quality in the VOI compared to the standard C-arm circular CBCT. We achieved a relative deviation less than 10% for both FSIM and UQI metrics between the reconstructed images from the optimized trajectories and the standard C-arm CBCT for all three targets. The whole trajectory optimization took approximately three to four minutes.
    Keywords Medicine ; R ; Science ; Q
    Subject code 629
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Suicidal wrist bites.

    Buschmann, Claas

    Forensic science, medicine, and pathology

    2024  

    Abstract: Wrist injuries are not uncommon in forensic routine and are usually found in the context of suicides or as a result of psychiatric illnesses, e.g., borderline disorders. Sharp objects (knives, broken glass, etc.) are usually used. In the case reported ... ...

    Abstract Wrist injuries are not uncommon in forensic routine and are usually found in the context of suicides or as a result of psychiatric illnesses, e.g., borderline disorders. Sharp objects (knives, broken glass, etc.) are usually used. In the case reported here, a paranoid-schizophrenic man not only injured himself with razor blades on both wrists, but he also inflicted extensive wrist bite injuries using his dental prosthesis. In addition to the severance of flexor tendons, venous vessels and the left radial artery were torn with subsequent blood loss. At the time of death, there was also acute exposure to methadone and opiates. Patients suffering from psychotic illnesses have an increased risk of committing spectacular or bizarre suicides.
    Language English
    Publishing date 2024-02-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2195904-3
    ISSN 1556-2891 ; 1547-769X
    ISSN (online) 1556-2891
    ISSN 1547-769X
    DOI 10.1007/s12024-023-00769-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: A decade of crystallization drops: crystallization of the cbb3 cytochrome c oxidase from Pseudomonas stutzeri.

    Buschmann, Sabine / Richers, Sebastian / Ermler, Ulrich / Michel, Hartmut

    Protein science : a publication of the Protein Society

    2014  Volume 23, Issue 4, Page(s) 411–422

    Abstract: The cbb3 cytochrome c oxidases are distant members of the superfamily of heme copper oxidases ...

    Abstract The cbb3 cytochrome c oxidases are distant members of the superfamily of heme copper oxidases. These terminal oxidases couple O2 reduction with proton transport across the plasma membrane and, as a part of the respiratory chain, contribute to the generation of an electrochemical proton gradient. Compared with other structurally characterized members of the heme copper oxidases, the recently determined cbb3 oxidase structure at 3.2 Å resolution revealed significant differences in the electron supply system, the proton conducting pathways and the coupling of O2 reduction to proton translocation. In this paper, we present a detailed report on the key steps for structure determination. Improvement of the protein quality was achieved by optimization of the number of lipids attached to the protein as well as the separation of two cbb3 oxidase isoenzymes. The exchange of n-dodecyl-β-D-maltoside for a precisely defined mixture of two α-maltosides and decanoylsucrose as well as the choice of the crystallization method had a most profound impact on crystal quality. This report highlights problems frequently encountered in membrane protein crystallization and offers meaningful approaches to improve crystal quality.
    MeSH term(s) Crystallization ; Crystallography, X-Ray ; Electron Transport Complex IV/chemistry ; Electron Transport Complex IV/isolation & purification ; Electron Transport Complex IV/metabolism ; Models, Molecular ; Pseudomonas stutzeri/enzymology
    Chemical Substances cbb3 oxidase (EC 1.9.3.-) ; Electron Transport Complex IV (EC 1.9.3.1)
    Language English
    Publishing date 2014-02-04
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1106283-6
    ISSN 1469-896X ; 0961-8368
    ISSN (online) 1469-896X
    ISSN 0961-8368
    DOI 10.1002/pro.2423
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Evaluation der Effizienz des Zero-Dose-C-Arm-Navigations-Ansatzes.

    Barbe, A G / de la Fuente, M / Belei, P / Buschmann, C / Radermacher, K / Mueller, M / Mumme, T

    Zeitschrift fur Orthopadie und Unfallchirurgie

    2010  Volume 148, Issue 5, Page(s) 554–558

    Abstract: ... These systems may be optimised by using a system called zero-dose c-arm navigation (ZDCAN). We investigate ... whether the available computer-assisted systems may be used to navigate the c-arm before image acquisition to obtain ... of the c-arm in order to evaluate efficiency and accuracy. Eight users acquired two perpendicular X-ray ...

    Title translation Evaluation of the efficiency of the zero-dose-C-arm navigation approach.
    Abstract Background: The efficiency and success of computer-assisted fluoroscopic navigation systems mainly depend on the quality of the process of image acquisition: obtaining the correct view of anatomic structures, relative orientation of multiplanar X-ray images and the necessary amount of radiation dose. These systems may be optimised by using a system called zero-dose c-arm navigation (ZDCAN). We investigate whether the available computer-assisted systems may be used to navigate the c-arm before image acquisition to obtain X-ray images with maximised accuracy and minimal radiation exposure.
    Methods: Based on position data of an optical tracking system combined with statistical deformable bone models, ZDCAN is able to generate a real-time preview of expected X-ray images of the lower extremities without using radiation. We performed a cadaver study on six full-body specimens comparing the zero-dose approach to conventional positioning of the c-arm in order to evaluate efficiency and accuracy. Eight users acquired two perpendicular X-ray images of the hip, the knee and the femoral diaphysis.
    Results: The number of X-ray images required to get a satisfying picture could be reduced to seven using the zero-dose approach; the conventional approach needed 11 images. The mean time did not differ significantly. Regarding the image quality, using ZDCAN quasi-orthogonality could be reached while the conventional approach showed a large variation of the relative orientation.
    Conclusion: Using ZDCAN, the amount of radiation can be reduced by requiring less X-ray images as well as reaching better accuracy.
    MeSH term(s) Body Burden ; Cadaver ; Humans ; Radiation Dosage ; Radiation Protection/methods ; Tomography, X-Ray Computed/methods ; Whole Body Imaging
    Language German
    Publishing date 2010-09
    Publishing country Germany
    Document type English Abstract ; Evaluation Studies ; Journal Article
    ZDB-ID 2280747-0
    ISSN 1864-6743 ; 1438-941X ; 1864-6697 ; 0044-3220
    ISSN (online) 1864-6743 ; 1438-941X
    ISSN 1864-6697 ; 0044-3220
    DOI 10.1055/s-0029-1240861
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: RAGE controls activation and anti-inflammatory signalling of protein C.

    Braach, Natascha / Frommhold, David / Buschmann, Kirsten / Pflaum, Johanna / Koch, Lutz / Hudalla, Hannes / Staudacher, Kathrin / Wang, Hongjie / Isermann, Berend / Nawroth, Peter / Poeschl, Johannes

    PloS one

    2014  Volume 9, Issue 2, Page(s) e89422

    Abstract: ... in mediation of anti-inflammatory properties of protein C.: Methods and results: We analyzed the effect ... of protein C on leukocyte adhesion and transmigration in WT- and RAGE-deficient mice using intravital ... microscopy of cremaster muscle venules during trauma- and TNFα-induced inflammation. Both, protein C (PC ...

    Abstract Aims: The receptor for advanced glycation endproducts, RAGE, is a multiligand receptor and NF-κB activator leading to perpetuation of inflammation. We investigated whether and how RAGE is involved in mediation of anti-inflammatory properties of protein C.
    Methods and results: We analyzed the effect of protein C on leukocyte adhesion and transmigration in WT- and RAGE-deficient mice using intravital microscopy of cremaster muscle venules during trauma- and TNFα-induced inflammation. Both, protein C (PC, Ceprotin, 100 U/kg) and activated protein C (aPC, 24 µg/kg/h) treatment significantly inhibited leukocyte adhesion in WT mice in these inflammation models. The impaired leukocyte adhesion after trauma-induced inflammation in RAGE knockout mice could not be further reduced by PC and aPC. After TNFα-stimulation, however, aPC but not PC treatment effectively blocked leukocyte adhesion in these mice. Consequently, we asked whether RAGE is involved in PC activation. Since RAGE-deficient mice and endothelial cells showed insufficient PC activation, and since thrombomodulin (TM) and endothelial protein C receptor (EPCR) are reduced on the mRNA and protein level in RAGE deficient endothelial cells, an involvement of RAGE in TM-EPCR-dependent PC activation is likely. Moreover, TNFα-induced activation of MAPK and upregulation of ICAM-1 and VCAM-1 are reduced both in response to aPC treatment and in the absence of RAGE. Thus, there seems to be interplay of the RAGE and the PC pathway in inflammation.
    Conclusion: RAGE controls anti-inflammatory properties and activation of PC, which might involve EPCR and TM.
    MeSH term(s) Animals ; Anti-Inflammatory Agents/metabolism ; Cell Adhesion/genetics ; Endothelial Cells/metabolism ; Endothelial Protein C Receptor ; Humans ; Inflammation/genetics ; Inflammation/metabolism ; Intercellular Adhesion Molecule-1/genetics ; Intercellular Adhesion Molecule-1/metabolism ; Leukocytes/metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Protein C/genetics ; Protein C/metabolism ; Receptor for Advanced Glycation End Products ; Receptors, Cell Surface/genetics ; Receptors, Cell Surface/metabolism ; Receptors, Immunologic/genetics ; Receptors, Immunologic/metabolism ; Signal Transduction/genetics ; Thrombomodulin/genetics ; Thrombomodulin/metabolism ; Tumor Necrosis Factor-alpha/genetics ; Tumor Necrosis Factor-alpha/metabolism ; Up-Regulation/genetics ; Vascular Cell Adhesion Molecule-1/genetics ; Vascular Cell Adhesion Molecule-1/metabolism
    Chemical Substances Anti-Inflammatory Agents ; Endothelial Protein C Receptor ; Procr protein, mouse ; Protein C ; Receptor for Advanced Glycation End Products ; Receptors, Cell Surface ; Receptors, Immunologic ; Thrombomodulin ; Tumor Necrosis Factor-alpha ; Vascular Cell Adhesion Molecule-1 ; Intercellular Adhesion Molecule-1 (126547-89-5)
    Language English
    Publishing date 2014-02-24
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0089422
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Identification and Characterization of the Novel Subunit CcoM in the cbb3₃Cytochrome c Oxidase from Pseudomonas stutzeri ZoBell.

    Kohlstaedt, Martin / Buschmann, Sabine / Xie, Hao / Resemann, Anja / Warkentin, Eberhard / Langer, Julian D / Michel, Hartmut

    mBio

    2016  Volume 7, Issue 1, Page(s) e01921–15

    Abstract: Unlabelled: Cytochrome c oxidases (CcOs), members of the heme-copper containing oxidase (HCO ... superfamily, are the terminal enzymes of aerobic respiratory chains. The cbb3-type cytochrome c oxidases (cbb3 ... CcO) form the C-family and have only the central catalytic subunit in common with the A- and B-family ...

    Abstract Unlabelled: Cytochrome c oxidases (CcOs), members of the heme-copper containing oxidase (HCO) superfamily, are the terminal enzymes of aerobic respiratory chains. The cbb3-type cytochrome c oxidases (cbb3-CcO) form the C-family and have only the central catalytic subunit in common with the A- and B-family HCOs. In Pseudomonas stutzeri, two cbb3 operons are organized in a tandem repeat. The atomic structure of the first cbb3 isoform (Cbb3-1) was determined at 3.2 Å resolution in 2010 (S. Buschmann, E. Warkentin, H. Xie, J. D. Langer, U. Ermler, and H. Michel, Science 329:327-330, 2010, http://dx.doi.org/10.1126/science.1187303). Unexpectedly, the electron density map of Cbb3-1 revealed the presence of an additional transmembrane helix (TMH) which could not be assigned to any known protein. We now identified this TMH as the previously uncharacterized protein PstZoBell_05036, using a customized matrix-assisted laser desorption ionization (MALDI)-tandem mass spectrometry setup. The amino acid sequence matches the electron density of the unassigned TMH. Consequently, the protein was renamed CcoM. In order to identify the function of this new subunit in the cbb3 complex, we generated and analyzed a CcoM knockout strain. The results of the biochemical and biophysical characterization indicate that CcoM may be involved in CcO complex assembly or stabilization. In addition, we found that CcoM plays a role in anaerobic respiration, as the ΔCcoM strain displayed altered growth rates under anaerobic denitrifying conditions.
    Importance: The respiratory chain has recently moved into the focus for drug development against prokaryotic human pathogens, in particular, for multiresistant strains (P. Murima, J. D. McKinney, and K. Pethe, Chem Biol 21:1423-1432, 2014, http://dx.doi.org/10.1016/j.chembiol.2014.08.020). cbb3-CcO is an essential enzyme for many different pathogenic bacterial species, e.g., Helicobacter pylori, Vibrio cholerae, and Pseudomonas aeruginosa, and represents a promising drug target. In order to develop compounds targeting these proteins, a detailed understanding of the molecular architecture and function is required. Here we identified and characterized a novel subunit, CcoM, in the cbb3-CcO complex and thereby completed the crystal structure of the Cbb3 oxidase from Pseudomonas stutzeri, a bacterium closely related to the human pathogen Pseudomonas aeruginosa.
    MeSH term(s) Electron Transport Complex IV/chemistry ; Electron Transport Complex IV/genetics ; Electron Transport Complex IV/metabolism ; Gene Knockout Techniques ; Protein Subunits/chemistry ; Protein Subunits/genetics ; Protein Subunits/metabolism ; Pseudomonas stutzeri/chemistry ; Pseudomonas stutzeri/enzymology ; Pseudomonas stutzeri/genetics ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Tandem Mass Spectrometry
    Chemical Substances Protein Subunits ; cbb3 oxidase (EC 1.9.3.-) ; Electron Transport Complex IV (EC 1.9.3.1)
    Language English
    Publishing date 2016-01-26
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2557172-2
    ISSN 2150-7511 ; 2161-2129
    ISSN (online) 2150-7511
    ISSN 2161-2129
    DOI 10.1128/mBio.01921-15
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Book ; Audio / Video ; Online: Development of serological assays for the detection of henipavirus specifi c antibodies

    Fischer, Kerstin* / Reis, Vinicius Pinho dos / Diederich, Sandra / Groschup, Martin H. / Weingartl, H. / Balkema-Buschmann, Anne

    2016  

    Keywords ddc:570
    Language English
    Publishing date 2016-10-21
    Publishing country de
    Document type Book ; Audio / Video ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Book ; Audio / Video ; Online: Development of serological assays for the detection of henipavirus specifi c antibodies

    Fischer, Kerstin* / Reis, Vinicius Pinho dos / Diederich, Sandra / Groschup, Martin H. / Weingartl, H. / Balkema-Buschmann, Anne

    2016  

    Keywords Text ; ddc:570
    Language English
    Publishing date 2016-10-21
    Publishing country de
    Document type Book ; Audio / Video ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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