1
|
Renikunta HV, Lazarow K, Gong Y, Shukla PC, Giral H, Kratzer A, Nageswaran V, Opitz L, Engel FB, Haghikia A, Paneni F, Von Kries JP, Streckfuss-Boemeke K, Landmesser U, Jakob P. A large-scale functional high-throughput screening identifies miR-515 and miR-519e as potent inducers of human iPSC-cardiomyocyte proliferation. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.2881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Ischemic heart failure persists as a global health problem despite optimized medical and adjunctive device therapies. Loss of cardiomyocytes in the absence of a proliferative response comprise a major contributor to pathological remodeling and death in this patient population. Experimental studies have shown that microRNAs (miRNAs) may be used as a therapeutic option to reinduce adult cardiomyocyte proliferation.
Purpose
This study thought to evaluate proliferative potential in human cardiomyocytes after overexpression and inhibition of 2019 miRNAs.
Methods
To identify miRNAs that regulate cardiomyocyte proliferation, we performed functional high-throughput screenings in human iPSC-derived cardiomyocytes (hiPSC-CM) after transient hypoxia. Herein, 2019 miRNA-mimics for overexpression and 2019 anti-miRs for inhibition were individually transfected to examine EdU-incorporation in hiPSC-CM. MiR-mimic-515 and miR-mimic-519e that induced the highest EdU-uptake, were further assessed by immunostaining and molecular methods for markers indicative of early and late mitosis. In addition, RNA-Sequencing in hiPSC-CM after overexpression of miR-515 and miR-519e was performed to examine differential gene expression and miRNA-modulated pathways involved in cardiomyocyte proliferation.
Results
Using a functional high-throughput screening, we assessed differential proliferative potential of 2019 miRNAs after transient hypoxia by transfecting both miR-inhibitor and miR-mimic libraries in human iPSC-derived cardiomyocytes (hiPSC-CM). Overexpression of 28 miRNAs substantially induced proliferative activity in hiPSC-CM, with an overrepresentation of miRNAs belonging to the C19MC-cluster and adjacent miR-371–373 family. Two of these miRNAs, miR-515 and miR-519e increased markers of early and late mitosis, with an additive cardiomyocyte turnover after transient hypoxia and substantially increased Aurora B-kinase activity in midbodies, indicative of cell division. These findings were supported by molecular studies using qRT-PCR, Western blot, and RNA-Sequencing after overexpression of miR-515 and miR-519e showing substantial alterations of signaling pathways relevant for cardiomyocytes proliferation in human iPSC-CM.
Conclusion
Collectively, these results support a critical role of miR-515 and miR-519e for induction of proliferation in human cardiomyocytes under hypoxic conditions, such as present in patients with ischemia-driven cardiomyopathy.
Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): This work was supported by the German Centre for Cardiovascular Research (DZHK), Deutsche Stiftung für Herzforschung (DSHF) and OPO Foundation.
Collapse
Affiliation(s)
- H V Renikunta
- Charite - Campus Benjamin Franklin, Department of Cardiology , Berlin , Germany
| | - K Lazarow
- Max Delbruck Center for Molecular Medicine, Leibniz-Institute for Molecular Pharmacology , Berlin , Germany
| | - Y Gong
- University of Zurich, Center for Molecular Cardiology , Schlieren , Switzerland
| | - P C Shukla
- Charite - Campus Benjamin Franklin, Department of Cardiology , Berlin , Germany
| | - H Giral
- Charite - Campus Benjamin Franklin, Department of Cardiology , Berlin , Germany
| | - A Kratzer
- Charite - Campus Benjamin Franklin, Department of Cardiology , Berlin , Germany
| | - V Nageswaran
- Charite - Campus Benjamin Franklin, Department of Cardiology , Berlin , Germany
| | - L Opitz
- University of Zurich, Functional Genomics Center Zurich UZH/ETH , Zurich , Switzerland
| | - F B Engel
- Friedrich Alexander University, Experimental Renal and Cardiovascular Research, Department of Nephropathology , Erlangen , Germany
| | - A Haghikia
- Charite - Campus Benjamin Franklin, Department of Cardiology , Berlin , Germany
| | - F Paneni
- University of Zurich, Center for Molecular Cardiology , Schlieren , Switzerland
| | - J P Von Kries
- Max Delbruck Center for Molecular Medicine, Leibniz-Institute for Molecular Pharmacology , Berlin , Germany
| | - K Streckfuss-Boemeke
- University Medical Center of Gottingen (UMG), Clinic for Cardiology and Pneumology , Goettingen , Germany
| | - U Landmesser
- Charite - Campus Benjamin Franklin, Department of Cardiology , Berlin , Germany
| | - P Jakob
- University Heart Center, Cardiology, University Hospital Zurich , Zurich , Switzerland
| |
Collapse
|
2
|
Jakob P, Thussing S. Vibrational Frequency Used as Internal Clock Reference to Access Molecule-Metal Charge-Transfer Times. Phys Rev Lett 2021; 126:116801. [PMID: 33798353 DOI: 10.1103/physrevlett.126.116801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
Dynamical charge transfer processes at molecule-metal interfaces proceed in the few fs timescale that renders them highly relevant to electronic excitations in optoelectronic devices. Yet, knowledge thereof is limited when electronic ground state situations are considered that implicate charge transfer directly at the fermi energy. Here we show that such processes can be accessed by means of vibrational excitations, with nonadiabatic electron-vibron coupling leading to distinct asymmetric line shapes. Thereby the characteristic timescale of this interfacial dynamical charge transfer can be derived by using the vibrational oscillation period as an internal clock reference.
Collapse
Affiliation(s)
- P Jakob
- Fachbereich Physik und Wissenschaftliches Zentrum für Materialwissenschaften der Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany
| | - S Thussing
- Fachbereich Physik und Wissenschaftliches Zentrum für Materialwissenschaften der Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany
| |
Collapse
|
3
|
Gram M, Gensler D, Winter P, Seethaler M, Jakob P, Nordbeck P. Rapid T1rho dispersion imaging for improved characterization of myocardial tissue using synthetic dispersion reconstruction. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
Over the past decade, CMRI has become the method of choice for characterizing fibrotic scars. Native T1ρ mapping offers an alternative to conventional T1 and T2 quantification techniques due to its high sensitivity to low-frequency processes. In addition, there is the possibility of T1ρ dispersion imaging, which could be used as a sensitive biomarker for assessing myocardial fibrosis [1]. However, due to a very long measurement time, T1ρ dispersion quantification in myocardium can hardly be done in the limited time of a small animal study. In this work we present a concept for rapid T1ρ dispersion quantification based on the new approach of synthetic dispersion reconstruction (SynDR).
Theory
A T1ρ map is calculated by measuring Nt T1ρ weighted images using different spin lock (SL) times. T1ρ dispersion quantification requires Nf T1ρ maps with different SL amplitudes. Hence the measurement time is very time consuming, because it requires the acquisition of Nt*Nf images (full mapping). With our new approach (SynDR), only a single T1ρ reference map and a series of dispersion weighted images need to be acquired. The T1ρ dispersion can be reconstructed by synthetically generated maps, whereby each map is calculated from the reference map and the dispersion weighted images, only requiring Nt+Nf images.
Methods
All measurements were performed on a 7T small animal scanner. The method was based on an optional cartesian/radial gradient echo sequence using large flip angles (45°) and an optimized readout sorting. The quantification accuracy of SynDR was compared with full mapping measurements in a phantom experiment and validated in vivo on mice. The synthetic T1ρ maps were used to perform a dispersion analysis in myocardium.
Results
The comparison between SynDR and the full mapping reference in phantoms showed a very high quantification accuracy with a mean/maximum deviation of 1.1% and 1.7%. Fig. 1 shows synthetic T1ρ maps (a) in healthy mice and the obtained dispersion map (b) using SynDR. In the dispersion analysis (c) a T1ρ slope of 5.6±1.5ms/kHz was obtained for myocardium. Here an acceleration factor of 4 could be realized in comparison to full mapping. In further measurements, an acceleration of 7.4 could be reached using a radial readout with KWIC filter view sharing.
Discussion
In this work, a novel T1ρ dispersion imaging method was presented that far exceeds the speed of conventional full mapping methods. The acceleration is based on avoiding unnecessary measurements of T1ρ weighted images through more efficient mathematical modeling. Further acceleration could be achieved using an optimized radial data acquisition. The method shows good image quality and high quantification accuracy both in phantom and in vivo. Based on the promising results, further studies in mice are planned to investigate the dispersion character of healthy and diseased tissues.
Reference
[1] Yin Q et al. Magn Reson Imaging. 2017 Oct; 42:69–73.
SynDR method and T1ρ dispersion analysis
Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): BRD, Bundesministerium für Bildung und Forschung
Collapse
Affiliation(s)
- M Gram
- University Hospital Wuerzburg, Department of Internal Medicine I, Wuerzburg, Germany
| | - D Gensler
- University Hospital Wuerzburg, Comprehensive Heart Failure Center (CHFC), Wuerzburg, Germany
| | - P Winter
- University Hospital Wuerzburg, Comprehensive Heart Failure Center (CHFC), Wuerzburg, Germany
| | - M Seethaler
- University of Wuerzburg, Experimental Physics 5, Wuerzburg, Germany
| | - P.M Jakob
- University of Wuerzburg, Experimental Physics 5, Wuerzburg, Germany
| | - P Nordbeck
- University Hospital Wuerzburg, Department of Internal Medicine I, Wuerzburg, Germany
| |
Collapse
|
4
|
Thussing S, Fernández L, Jakob P. Thermal stability and interlayer exchange processes in heterolayers of TiOPc and PTCDA on Ag(1 1 1). J Phys Condens Matter 2019; 31:134002. [PMID: 30625431 DOI: 10.1088/1361-648x/aafcf8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Organic-organic interfaces, in particular donor-acceptor type heterointerfaces, represent central elements of organic electronic devices. Understanding and controlling their physical properties is key to improve and modify their performance. For this purpose we have investigated the structural properties and thermal evolution of molecular heterointerface model systems. Specifically, various stacked titanyl-phthalocyanine (TiOPc)-3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) heterolayers grown on Ag(1 1 1) have been examined using Fourier transform infrared absorption spectroscopy and spot-profile analysis low-energy electron diffraction. An accurate description of the thermal evolution and prevalence of the various phases of TiOPc and PTCDA is derived from the spectral signatures of the two molecular species explored in previous studies. Exceptionally high thermal stability is found for stacked heterolayers comprising TiOPc double layers with characteristic up-down arrangement of its axial Ti-O unit and single layers of PTCDA. Thereby, interlayer exchange is negligible in a wide temperature range ([Formula: see text] K). This is ascribed to attractive intermolecular interaction (dipole-dipole interaction, hydrogen bonding) among the TiOPc molecules oriented face-to-face within the TiOPc bilayer sheet. Stacked layers of comprising single layers of TiOPc and of PTCDA turn out to be thermally much less stable and more heterogeneous. In the course of their thermal evolution, a number of processes such as interlayer exchange, TiOPc double-layer formation and dewetting are encountered.
Collapse
Affiliation(s)
- S Thussing
- Fachbereich Physik und Wissenschaftliches Zentrum für Materialwissenschaften der Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany
| | | | | |
Collapse
|
5
|
Zaitsev NL, Jakob P, Tonner R. Structure and vibrational properties of the PTCDA/Ag(1 1 1) interface: bilayer versus monolayer. J Phys Condens Matter 2018; 30:354001. [PMID: 30039803 DOI: 10.1088/1361-648x/aad576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The structural and vibrational properties of metal-organic interfaces have been examined by means of infrared (IR) absorption spectroscopy and density functional theory (DFT) with an approach accounting for long-range dispersive interactions. We focus on a comparative study of the PTCDA monolayer and bilayer on Ag(1 1 1). The equilibrium geometry at the molecule-metal interface and the IR spectrum of the chemisorbed monolayer of PTCDA on Ag(1 1 1) are well described by the computations. In the bilayer structure, the presence of a physisorbed adlayer on top of PTCDA/Ag(1 1 1) presents a challenge for DFT. As previously described for other systems, the polarization of the substrate is not captured correctly and results in too low energies of frontier molecular orbitals. This results in an apparent contribution from the vibrations of second-layer PTCDA to the IR spectrum due to interfacial dynamical charge transfer processes. After removing these peaks with artificially strong intensity, calculated and experimental data show good agreement and the IR spectrum can be described as the sum of the spectra of the PTCDA/Ag(1 1 1) contact layer and a physisorbed PTCDA monolayer on top.
Collapse
Affiliation(s)
- N L Zaitsev
- Laboratory of Theoretical Physics, Institute of Molecule and Crystal Physics-Subdivision of the Ufa Federal Research Center of the Russian Academy of Sciences, 450075, Ufa, Russia. Laboratory of Nanostructured Surfaces and Coating, Tomsk State University, 634050, Tomsk, Russia
| | | | | |
Collapse
|
6
|
Jakob P, Kacprowski T, Abdelwahed YS, Riedel M, Staehli BE, Kraenkel N, Renikunta H, Meteva D, Seppelt C, Lauten A, Skurk C, Voelker U, Ameling S, Landmesser U, Leistner DM. P767Identification of circulating miRNA-abundances in ruptured versus eroded lesions: A combined optical coherence tomography and miRNA-profiling approach in patients with acute coronary syndrome. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy564.p767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- P Jakob
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - T Kacprowski
- University Medicine of Greifswald, Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, Greifswald, Germany
| | - Y S Abdelwahed
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - M Riedel
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - B E Staehli
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - N Kraenkel
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - H Renikunta
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - D Meteva
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - C Seppelt
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - A Lauten
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - C Skurk
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - U Voelker
- University Medicine of Greifswald, Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, Greifswald, Germany
| | - S Ameling
- University Medicine of Greifswald, Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, Greifswald, Germany
| | - U Landmesser
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | - D M Leistner
- Charite - Campus Benjamin Franklin, Department of Cardiology, Berlin, Germany
| | | |
Collapse
|
7
|
Kratzer A, Giral H, Franke V, Kraenkel N, Mueller M, Moobed M, Kuschnerus K, Jakob P, Luescher T, Akalin A, Landmesser U. P6269Next-generation-sequencing reveals diverse inflammasome components within monocyte subpopulations: differential activation in healthy subjects and patients with acute coronary syndrome. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx493.p6269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
8
|
Malepu S, Renikunta H, Kraenkel N, Kratzer A, Giral H, Hasenfuss G, Stachelscheid H, Streckfuss-Boemeke K, Landmesser U, Jakob P. 5918Ischemia-driven exosome release of human iPSC-CM-derived cardiomyocytes increase viability of endothelial cells via pro-survival factors. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx493.5918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
9
|
Jakob P. Fenestrierte Aortenprothesen. ROFO-FORTSCHR RONTG 2016. [DOI: 10.1055/s-0036-1581533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
10
|
Triphan S, Wielpütz M, Heussel CP, Biederer J, Kauczor HU, Jakob P, Jobst B. Echo-time dependence of observed lung T1 in COPD patients: preliminary results. Pneumologie 2015. [DOI: 10.1055/s-0035-1556615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
11
|
Herz S, Vogel P, Brede C, Kampf T, Rückert M, Veldhoen S, Jakob P, Behr V, Beilhack A, Bley T. Magnetic Particle Imaging/MRT-Fusionsbildgebung: Machbarkeitsstudie an einem murinen Graft-versus-Host Disease Modell. ROFO-FORTSCHR RONTG 2015. [DOI: 10.1055/s-0035-1550867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
12
|
Jakob P. Aortenaneurysma – ein endoluminaler Komplexeingriff. ROFO-FORTSCHR RONTG 2015. [DOI: 10.1055/s-0035-1551082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
13
|
Renne J, Lauermann P, Hinrichs J, Schönfeld C, Sorrentino S, Gutberlet M, Jakob P, Haverich A, Warnecke G, Wacker F, Welte T, Gottlieb J, Vogel-Claussen J. T1-mapping magnetic resonance imaging for the detection of chronic lung allograft dysfunction – initial results. Pneumologie 2014. [DOI: 10.1055/s-0034-1376832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
14
|
Schuler B, Rieger G, Gubser M, Arras M, Gianella M, Vogel O, Jirkof P, Cesarovic N, Klohs J, Jakob P, Brock M, Gorr TA, Baum O, Hoppeler H, Samillan-Soto V, Gassmann M, Fischer JA, Born W, Vogel J. Endogenous α-calcitonin-gene-related peptide promotes exercise-induced, physiological heart hypertrophy in mice. Acta Physiol (Oxf) 2014; 211:107-21. [PMID: 24479375 DOI: 10.1111/apha.12244] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 10/10/2013] [Accepted: 01/24/2014] [Indexed: 11/29/2022]
Abstract
AIM It is unknown how the heart distinguishes various overloads, such as exercise or hypertension, causing either physiological or pathological hypertrophy. We hypothesize that alpha-calcitonin-gene-related peptide (αCGRP), known to be released from contracting skeletal muscles, is key at this remodelling. METHODS The hypertrophic effect of αCGRP was measured in vitro (cultured cardiac myocytes) and in vivo (magnetic resonance imaging) in mice. Exercise performance was assessed by determination of maximum oxygen consumption and time to exhaustion. Cardiac phenotype was defined by transcriptional analysis, cardiac histology and morphometry. Finally, we measured spontaneous activity, body fat content, blood volume, haemoglobin mass and skeletal muscle capillarization and fibre composition. RESULTS While αCGRP exposure yielded larger cultured cardiac myocytes, exercise-induced heart hypertrophy was completely abrogated by treatment with the peptide antagonist CGRP(8-37). Exercise performance was attenuated in αCGRP(-/-) mice or CGRP(8-37) treated wild-type mice but improved in animals with higher density of cardiac CGRP receptors (CLR-tg). Spontaneous activity, body fat content, blood volume, haemoglobin mass, muscle capillarization and fibre composition were unaffected, whereas heart index and ventricular myocyte volume were reduced in αCGRP(-/-) mice and elevated in CLR-tg. Transcriptional changes seen in αCGRP(-/-) (but not CLR-tg) hearts resembled maladaptive cardiac phenotype. CONCLUSIONS Alpha-calcitonin-gene-related peptide released by skeletal muscles during exercise is a hitherto unrecognized effector directing the strained heart into physiological instead of pathological adaptation. Thus, αCGRP agonists might be beneficial in heart failure patients.
Collapse
Affiliation(s)
- B. Schuler
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zürich; Zürich Switzerland
- Department of Physiology, Anatomy and Genetics; University of Oxford; Oxford UK
| | - G. Rieger
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - M. Gubser
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - M. Arras
- Division of Surgical Research; University Hospital Zürich; Zürich Switzerland
| | - M. Gianella
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zürich; Zürich Switzerland
| | - O. Vogel
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zürich; Zürich Switzerland
| | - P. Jirkof
- Division of Surgical Research; University Hospital Zürich; Zürich Switzerland
| | - N. Cesarovic
- Division of Surgical Research; University Hospital Zürich; Zürich Switzerland
| | - J. Klohs
- Institute for Biomedical Engineering; University of Zurich and Swiss Federal Institute of Technology; Zürich (ETHZ); Zürich Switzerland
| | - P. Jakob
- Institute of Physiology and Cardiovascular Research; University of Zürich; Zürich Switzerland
| | - M. Brock
- Division of Pulmonology; University Hospital Zürich; Zürich Switzerland
- Zürich Center for Integrative Human Physiology (ZIHP); Zürich Switzerland
| | - T. A. Gorr
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zürich; Zürich Switzerland
- Clinic IV; Division of Pediatric Hematology and Oncology; University Medical Center; Freiburg Germany
| | - O. Baum
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - H. Hoppeler
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - V. Samillan-Soto
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zürich; Zürich Switzerland
- Physiology Department; Medical School; Universidad Alas Peruanas; Lima Peru
| | - M. Gassmann
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zürich; Zürich Switzerland
- Zürich Center for Integrative Human Physiology (ZIHP); Zürich Switzerland
- Universidad Peruana Cayetano Heredia (UPCH); Lima Peru
| | - J. A. Fischer
- Former Research Laboratory for Calcium Metabolism; Orthopedic University Hospital Zürich; Zürich Switzerland
| | - W. Born
- Former Research Laboratory for Calcium Metabolism; Orthopedic University Hospital Zürich; Zürich Switzerland
| | - J. Vogel
- Institute of Veterinary Physiology; Vetsuisse Faculty University of Zürich; Zürich Switzerland
| |
Collapse
|
15
|
Jakob P, Briand S, Mocharla P, Kraenkel N, Mueller M, Manes C, Noll G, Ruschitzka F, Luescher TF, Landmesser U. Reduced microRNA-130a expression in early outgrowth cells from patients with coronary disease: a novel mechanism limiting capacity of early outgrowth cells for vascular repair. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht308.p1463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
16
|
Holy EW, Jakob P, Akhmedov A, Camici GG, Beer JH, Luescher TF, Tanner FC. PI3K/p110alpha inhibition selectively interferes with arterial thrombosis and neointima formation, but not re-endothelialization: a new concept in drug-eluting stent design. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.4369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
17
|
Akhmedov A, Braunersreuther V, Montecucco F, Jakob P, Camici GG, Mach F, Luescher TF. Genetic deletion of p66Shc adaptor protein leads to increased myocardial infarction by inhibiting RISK and SAFE prosurvival pathways. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht308.p1858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
18
|
Renne J, Hinrichs J, Schönfeld C, Gutberlet M, Jakob P, Wacker F, Vogel-Claussen J. Lungenanalyse mittels Sauerstoff-gestützter T1-mapping MRT: Reproduzierbarkeit und Einfluss unterschiedlicher Sauerstoff-Applikation. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
19
|
Renne J, Hohlfeld JM, Hinrichs J, Schönfeld C, Gutberlet M, Winkler C, Faulenbach C, Jakob P, Krug N, Wacker F, Vogel-Claussen J. Funktionelle Analyse pulmonaler Inflammation nach endobronchialer Allergenprovokation mittels T1-mapping MRT. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
20
|
Renne J, Hohlfeld JM, Schaumann F, Hinrichs J, Schönfeld C, Gutberlet M, Faulenbach C, Jakob P, Krug N, Wacker F, Vogel-Claussen J. T1-mapping MRT zur Quantifizierung der pulmonalen Inflammation nach endobronchialer Allergenprovokation bei Patienten mit Asthma bronchiale. ROFO-FORTSCHR RONTG 2012. [DOI: 10.1055/s-0032-1311257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
21
|
|
22
|
Davidson SM, Duchen MM, Yellon DM, Fields L, Zaccolo M, Laeremans H, Daskalopoulos EP, Janssen BJA, Blankesteijn WM, Tillmanns J, Hoffmann D, Habbaba Y, Fraccarollo D, Galuppo P, Bauersachs J, Novella S, Segarra G, Dantas AP, Bueno-Beti C, Novensa L, Lazaro-Franco M, Martinez-Gil N, Medina P, Hermenegildo C, Ohanian J, Liao A, Trafford AW, Ohanian V, Perez-Moreno A, Garcia-Canadilla P, Dominguez JM, Crispi F, Gratacos E, Amat-Roldan I, Gotschy A, Herold V, Bauer E, Schrodt C, Lykowsky G, Rommel E, Jakob P, Bauer W, Shah M, Sikkel MB, Desplantez T, Collins TP, O'Gara P, Harding SE, Lyon AR, Macleod KT, Ferrantini C, Sacconi L, Lotti I, Coppini R, Tesi C, Yan P, Loew LM, Cerbai E, Poggesi C, Pavone FS, Franco D, Daimi H, Dominguez JN, Hove-Madsen L, Cinca J, Vazquez E, Aranega AE, Poon KL, Kirchmaier BC, Schwerte T, Huisken J, Winkler C, Jungblut BC, Stainier DY, Brand T, Stuckey DJ, Tremoleda JL, Mcsweeney S, Fiedler L, Harada M, Carr CA, Tyler DJ, Gsell W, Clarke K, Schneider MD, Sequeira V, Regan JA, Michels M, Ten Cate FJ, Van Slegtenhorst MA, Stienen GJM, Dos Remedios C, Van Der Velden J. Oral abstract presentations. Cardiovasc Res 2012. [DOI: 10.1093/cvr/cvr335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
23
|
Armbrust N, Güdde J, Jakob P, Höfer U. Time-resolved two-photon photoemission of unoccupied electronic states of periodically rippled graphene on Ru(0001). Phys Rev Lett 2012; 108:056801. [PMID: 22400950 DOI: 10.1103/physrevlett.108.056801] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Indexed: 05/31/2023]
Abstract
The unoccupied electronic states of epitaxially grown graphene on Ru(0001) have been explored by time- and angle-resolved two-photon photoemission. We identify a Ru derived resonance and a Ru/graphene interface state at 0.91 and 2.58 eV above the Fermi level, as well as three image-potential derived states close to the vacuum level. The most strongly bound, short-lived, and least dispersing image-potential state is suggested to have some quantum-well character with a large amplitude below the graphene hills. The two other image-potential states are attributed to a series of slightly decoupled states. Their lifetimes and dispersions are indicative of electrons moving almost freely above the valley areas of the moiré superstructure of graphene.
Collapse
Affiliation(s)
- N Armbrust
- Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität, 35032 Marburg, Germany
| | | | | | | |
Collapse
|
24
|
Nordbeck P, Beer M, Geistert W, Kaufmann R, Köstler H, Pabst T, Warmuth M, Gensler D, Reiter T, Hoffmeister S, Jakob P, Ladd M, Quick H, Bauer W, Ritter O. Katheterablation bei Herzrhythmusstörungen unter MR-Echtzeitbildgebung. ROFO-FORTSCHR RONTG 2012. [DOI: 10.1055/s-0031-1300860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
|
25
|
Abstract
Current diagnostic tools for the assessment of lung function are limited by global measurements or the need for radioactive tracers. Ideally, these tools should allow quantitative, regional distinct analyses without exposure to radiation. The current paper presents oxygen-enhanced functional MRI for assessment of lung ventilation. First applied in humans in 1996, a considerable amount of experience is now available on 1.5T scanners. The generation of quantitative T1-maps shows a high clinical potential. Low-field MR scanners, which are mostly open-designed, are especially interesting for functional lung imaging. The open design has advantages in respect to patient comfort by lower noise production and easy access to the patients and the costs are lower (no need for helium cooling). Lower signal-to-noise ratios can be overcome by changing the relaxation times. New navigator techniques allow further compensations. This article focuses on the presentation of low-field scanners and the application of T1 and T2(*) maps is described for healthy volunteers and first patients.
Collapse
Affiliation(s)
- M Beer
- Institut für Röntgendiagnostik, Universitätsklinikum Würzburg, Josef-Schneider-Str. 2, 97080 Würzburg.
| | | | | | | | | | | | | |
Collapse
|
26
|
Westhoff M, Zimmermann D, Schneider H, Wegner LH, Gessner P, Jakob P, Bamberg E, Shirley S, Bentrup FW, Zimmermann U. Evidence for discontinuous water columns in the xylem conduit of tall birch trees. Plant Biol (Stuttg) 2009; 11:307-327. [PMID: 19470103 DOI: 10.1111/j.1438-8677.2008.00124.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The continuity of the xylem water columns was studied on 17- to 23-m tall birch trees (trunk diameter about 23 cm; first branching above 10 m) all year round. Fifty-one trees were felled, and 5-cm thick slices or 2-m long boles were taken at regular, relatively short intervals over the entire height of the trees. The filling status of the vessels was determined by (i) xylem sap extraction from trunk and branch pieces (using the gas bubble-based jet-discharge method and centrifugation) and from trunk boles (using gravity discharge); (ii) (1)H nuclear magnetic resonance imaging of slice pieces; (iii) infusion experiments (dye, (86)Rb(+), D(2)O) on intact trees and cut branches; and (iv) xylem pressure measurements. This broad array of techniques disclosed no evidence for continuous water-filled columns, as postulated by the Cohesion-Tension theory, for root to apex directed mass transport. Except in early spring (during the xylem refilling phase) and after extremely heavy rainfall during the vegetation period, cohesive/mobile water was found predominantly at intermediate heights of the trunks but not at the base or towards the top of the tree. Similar results were obtained for branches. Furthermore, upper branches generally contained more cohesive/mobile water than lower branches. The results suggest that water lifting occurs by short-distance (capillary, osmotic and/or transpiration-bound) tension gradients as well as by mobilisation of water in the parenchymatic tissues and the heartwood, and by moisture uptake through lenticels.
Collapse
Affiliation(s)
- M Westhoff
- Lehrstuhl für Biotechnologie, Biozentrum, Universität Würzburg, Würzburg, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Raya JG, Melkus G, Dietrich O, Reiser MF, Jakob P, Glaser C. Multiparametrische Charakterisierung des gesunden und kranken Knorpels unter Druck bei 17.6 T. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1221579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
28
|
Glaser C, Filidoro L, Raya JG, Weber D, Horng A, Arnoldi A, Kellerer A, Weber J, Jakob P, Putz R, Muetzel E, Reiser MF. Hochaufgelöste Diffusions-Tensor-MRT der Kollagenfaserarchitektur im Gelenkknorpel: Korrelation mit der Rasterelektronenmikroskopie. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1221578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
29
|
Westhoff M, Schneider H, Zimmermann D, Mimietz S, Stinzing A, Wegner LH, Kaiser W, Krohne G, Shirley S, Jakob P, Bamberg E, Bentrup FW, Zimmermann U. The mechanisms of refilling of xylem conduits and bleeding of tall birch during spring. Plant Biol (Stuttg) 2008; 10:604-623. [PMID: 18761499 DOI: 10.1111/j.1438-8677.2008.00062.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Seasonal variations in osmolality and components of xylem sap in tall birch trees were determined using several techniques. Xylem sap was extracted from branch and trunk sections of 58 trees using the very rapid gas bubble-based jet-discharge method. The 5-cm long wood pieces were taken at short intervals over the entire tree height. The data show that large biphasic osmolality gradients temporarily exist within the conducting xylem conduits during leaf emergence (up to 272 mosmol x kg(-1) at the apex). These gradients (arising mainly from glucose and fructose) were clearly held within the xylem conduit as demonstrated by (1)H NMR imaging of intact twigs. Refilling experiments with benzene, sucrose infusion, electron and light microscopy, as well as (1)H NMR chemical shift microimaging provided evidence that the xylem of birch represents a compartment confined by solute-reflecting barriers (radial: lipid linings/lipid bodies; axial: presumably air-filled spaces). These features allow transformation of osmolality gradients into osmotic pressure gradients. Refilling of the xylem occurs by a dual mechanism: from the base (by root pressure) and from the top (by hydrostatic pressure generated by xylem-bound osmotic pressure). The generation of osmotic pressure gradients was accompanied by bleeding. Bleeding could be observed at a height of up to 21 m. Bleeding rates measured at a given height decreased exponentially with time. Evidence is presented that the driving force for bleeding is the weight of the static water columns above the bleeding point. The pressure exerted by the water columns and the bleeding volume depend on the water-filling status of (communicating) vessels.
Collapse
Affiliation(s)
- M Westhoff
- Lehrstuhl für Biotechnologie, Biozentrum, Universität Würzburg, Würzburg, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Kaufmann I, Seiberlich N, Haase A, Jakob P. Diffusion generated T1 and T2 contrast. J Magn Reson 2008; 192:139-150. [PMID: 18316216 DOI: 10.1016/j.jmr.2008.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Revised: 02/07/2008] [Accepted: 02/08/2008] [Indexed: 05/26/2023]
Abstract
In MR images of porous organic samples (such as roots or wood) in water media, the sample is often surrounded by a bright ring, with a corresponding decreased T1 value in T1 maps. When the medium is removed, or contrast agents are added, the ring disappears, indicating that the signal does not originate in the outer layers of the sample, but from the medium itself. It can be shown that this "bright ring effect" is only observed when the medium experiences a reduction in T1 when permeating the sample. In order to investigate this effect, a computer model was used to simulate the diffusion of magnetisation between regions that exhibit different relaxation constants. Using this model, the origin of the signal increase was found to be an inflow effect, as diffusion transports relaxed magnetisation from the boundary regions of the sample into the surrounding medium. In the case of the "bright ring" around the plants described above, a mixing of short T1 values from within the sample and long T1 values within the medium occurs, yielding a "transition region" between the two values. There, a signal increase can be observed at T1 weighted images, compared to the signal from the medium beyond this transition region. The width of the transition region is on the order of magnitude of the diffusion displacement that is calculated from the T1 value as diffusion time. In addition to causing the bright ring around the plant samples, this diffusion effect also limits the resolution of the relaxation time maps. This effect is not limited to T1 relaxation but also applies to T2 relaxation. However, at high B0 field strengths such as those used in this study (11.7 T), a T2 effect is not usually observed due to the considerably shorter T2 times in plants (about 50 ms, compared to T1 times of higher than 1 s). Because the diffusion length during this T2 relaxation is short with respect to the resolution of the imaging experiments, no T2 ring effect is seen.
Collapse
Affiliation(s)
- I Kaufmann
- Department of Physics, EP5 (Biophysics), University of Würzburg, Würzburg, Germany.
| | | | | | | |
Collapse
|
31
|
Zimmermann D, Westhoff M, Zimmermann G, Gessner P, Gessner A, Wegner LH, Rokitta M, Ache P, Schneider H, Vásquez JA, Kruck W, Shirley S, Jakob P, Hedrich R, Bentrup FW, Bamberg E, Zimmermann U. Foliar water supply of tall trees: evidence for mucilage-facilitated moisture uptake from the atmosphere and the impact on pressure bomb measurements. Protoplasma 2008; 232:11-34. [PMID: 18176835 DOI: 10.1007/s00709-007-0279-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Accepted: 06/05/2007] [Indexed: 05/25/2023]
Abstract
The water supply to leaves of 25 to 60 m tall trees (including high-salinity-tolerant ones) was studied. The filling status of the xylem vessels was determined by xylem sap extraction (using jet-discharge, gravity-discharge, and centrifugation) and by (1)H nuclear magnetic resonance imaging of wood pieces. Simultaneously, pressure bomb experiments were performed along the entire trunk of the trees up to a height of 57 m. Clear-cut evidence was found that the balancing pressure (P(b)) values of leafy twigs were dictated by the ambient relative humidity rather than by height. Refilling of xylem vessels of apical leaves (branches) obviously mainly occurred via moisture uptake from the atmosphere. These findings could be traced back to the hydration and rehydration of mucilage layers on the leaf surfaces and/or of epistomatal mucilage plugs. Xylem vessels also contained mucilage. Mucilage formation was apparently enforced by water stress. The observed mucilage-based foliar water uptake and humidity dependency of the P(b) values are at variance with the cohesion-tension theory and with the hypothesis that P(b) measurements yield information about the relationships between xylem pressure gradients and height.
Collapse
Affiliation(s)
- D Zimmermann
- Abteilung für Biophysikalische Chemie, Max-Planck-Institut für Biophysik, Frankfurt am Main, Federal Republic of Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Basse-Lusebrink T, Kampf T, Weber M, Heymer A, Ebert R, Noth U, Bauer W, Jakob P, Haddad D. Double-labeled Mesenchymal Stem Cells for 1H / 19F MR Imaging. J Stem Cells Regen Med 2007; 2:88-89. [PMID: 24692922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- Tc Basse-Lusebrink
- Department of Experimental Physics 5, University of Wurzburg , Am Hubland, 97074 Wurzburg, Germany
| | - T Kampf
- Department of Experimental Physics 5, University of Wurzburg , Am Hubland, 97074 Wurzburg, Germany
| | - M Weber
- Orthopedic Center for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstr. 11, 97074 Wurzburg, Germany
| | - A Heymer
- Orthopedic Center for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstr. 11, 97074 Wurzburg, Germany
| | - R Ebert
- Orthopedic Center for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstr. 11, 97074 Wurzburg, Germany
| | - U Noth
- Orthopedic Center for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstr. 11, 97074 Wurzburg, Germany
| | - Wr Bauer
- Medical Clinic and Polyclinic, University Hospital , Josef-Schneider-Strasse 2, 97080 Wurzburg, Germany
| | - P Jakob
- Department of Experimental Physics 5, University of Wurzburg , Am Hubland, 97074 Wurzburg, Germany ; Research Center Magnetic-Resonance-Bavaria , Am Hubland, 97074 Wurzburg, Germany
| | - D Haddad
- Research Center Magnetic-Resonance-Bavaria , Am Hubland, 97074 Wurzburg, Germany ; Department of Experimental Physics 5, University of Wurzburg , Am Hubland, 97074 Wurzburg, Germany
| |
Collapse
|
33
|
Wilms A, Weber M, Haddad D, Heymer A, Basse-Lusebrink T, Steinert A, Jakob P, Noth U, Gohlke F, Rolf O. Cell-based therapy of fatty degeneration after rotator cuff tears. J Stem Cells Regen Med 2007; 2:190-191. [PMID: 24692992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- A Wilms
- Orthopaedic Centre for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstrasse 11, 97074 Wurzburg, Germany
| | - M Weber
- Orthopaedic Centre for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstrasse 11, 97074 Wurzburg, Germany
| | - D Haddad
- Research Center Magnetic-Resonance-Bavaria, Am Hubland, 97074 Wurzburg, Germany
| | - A Heymer
- Orthopaedic Centre for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstrasse 11, 97074 Wurzburg, Germany
| | - T Basse-Lusebrink
- Department of Physics, EPV, University of Wurzburg, Am Hubland, 97074 Wurzburg, Germany
| | - A Steinert
- Orthopaedic Centre for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstrasse 11, 97074 Wurzburg, Germany
| | - P Jakob
- Research Center Magnetic-Resonance-Bavaria, Am Hubland, 97074 Wurzburg, Germany ; Department of Physics, EPV, University of Wurzburg, Am Hubland, 97074 Wurzburg, Germany
| | - U Noth
- Orthopaedic Centre for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstrasse 11, 97074 Wurzburg, Germany
| | - F Gohlke
- Orthopaedic Centre for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstrasse 11, 97074 Wurzburg, Germany
| | - O Rolf
- Orthopaedic Centre for Musculoskeletal Research, Division of Tissue Engineering, University of Wurzburg , Brettreichstrasse 11, 97074 Wurzburg, Germany
| |
Collapse
|
34
|
Heymer A, Haddad D, Weber M, Jakob P, Noth U. Iron oxide labeling of human mesenchymal stem cells in collagen type I hydrogels for cellular MR imaging. J Stem Cells Regen Med 2007; 2:192-193. [PMID: 24692993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- A Heymer
- Musculoskeletal Research Center, Orthopedic Department, University of Wuerzburg , Brettreichstrasse 11, 97074 Wuerzburg, Germany
| | - D Haddad
- Research Center Magnetic-Resonance-Bavaria , Am Hubland, 97074 Wuerzburg, Germany ; Department of Physics, EPV , University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - M Weber
- Musculoskeletal Research Center, Orthopedic Department, University of Wuerzburg , Brettreichstrasse 11, 97074 Wuerzburg, Germany
| | - P Jakob
- Research Center Magnetic-Resonance-Bavaria , Am Hubland, 97074 Wuerzburg, Germany ; Department of Physics, EPV , University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - U Noth
- Musculoskeletal Research Center, Orthopedic Department, University of Wuerzburg , Brettreichstrasse 11, 97074 Wuerzburg, Germany
| |
Collapse
|
35
|
Bernhardt J, Oechsner M, Jakob P, Koestler H, Hahn D, Darge K, Hebestreit H, Beer M. Etablierung und klinische Anwendung optimierter GRE-Sequenzen zum Nachweis Mukoviszidose-assoziierter pulmonaler Veränderungen bei Kindern und Jugendlichen an einem offenen 0,2T MR-Tomographen. ROFO-FORTSCHR RONTG 2007. [DOI: 10.1055/s-2007-976913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
36
|
Oechsner M, Stäb D, Jakob P, Arnold JF, Köstler H, Pabst T, Hahn D, Beer M. Funktionelle Lungenbildgebung mit MRT bei 0.2 Tesla unter Verwendung von Kontrastmittel und Sauerstoff. ROFO-FORTSCHR RONTG 2007. [DOI: 10.1055/s-2007-977059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
37
|
Weininger M, Beissert M, Oechsner M, Jakob P, Köstler H, Hahn D, Beer M. Quantitative Perfusionsmessung an der gesunden Lunge mittels kontrastverstärkter MRT. ROFO-FORTSCHR RONTG 2007. [DOI: 10.1055/s-2007-976823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
38
|
Ernst C, Schulenburg J, Jakob P, Dahms S, Lopez AM, Nychas G, Werber D, Klein G. Efficacy of amphoteric surfactant- and peracetic acid-based disinfectants on spores of bacillus cereus in vitro and on food premises of the German armed forces. J Food Prot 2006; 69:1605-10. [PMID: 16865893 DOI: 10.4315/0362-028x-69.7.1605] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In mass catering facilities of the German Armed Forces, foodborne outbreaks are commonly attributed to Bacillus cereus, and spores of this organism are regularly found on equipment surfaces. B. cereus is the causative agent of foodborne emetic or diarrheic disease. Hence, the use of sporicidal disinfectants may provide a starting point for successful risk mitigation of diseases associated with B. cereus. In this study, the amphoteric surfactant-based disinfectant (product A) that has been routinely used in catering facilities of the German Armed Forces and a peracetic acid-based disinfectant (product B) were compared for their efficacy against B. cereus spores in laboratory tests and under field conditions. In a carrier test for B. cereus spores, product A displayed no efficacy against spores of the test strain. In contrast, a substantial reduction in spore concentration (>5-log reduction) was achieved with product B. In a controlled trial conducted in seven Army catering facilities, the reduction in the number of B. cereus-positive samples was significantly greater (P < 0.001) for product B (from 28% initial contamination to 3% after application) than for product A (from 33 to 21%). Product B was estimated to be 6.25 times more efficacious than product A. Field trials confirmed the higher efficacy of the peracetic acid-based disinfectant to reduce B. cereus contamination on surfaces as found for the in vitro experiments. The tests used to assess the sporicidal effects of disinfectants were adequate under practice conditions and could be used for sporicidal testing of disinfectants for catering and food production establishments.
Collapse
Affiliation(s)
- C Ernst
- Bundeswehr School of Dog Handling, Koblenz, Germany
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Sieland K, Stroh A, Faber C, Neuberger T, Weir K, Mueller S, Lorenz P, Grune T, Jakob P, Taupitz M, Pilgrimm H, Zimmer C. CMR 2005: 9.05: Magnetic labeling andin vivo tracking of embryonic stem cells: efficacy, biological effects, high-field detection limits and long-term results. Contrast Media Mol Imaging 2006. [DOI: 10.1002/cmmi.57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
40
|
Weber T, Vroemen M, Behr V, Neuberger T, Jakob P, Haase A, Schuierer G, Bogdahn U, Faber C, Weidner N. In vivo high-resolution MR imaging of neuropathologic changes in the injured rat spinal cord. AJNR Am J Neuroradiol 2006; 27:598-604. [PMID: 16552001 PMCID: PMC7976991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
BACKGROUND AND PURPOSE MR imaging is the most comprehensive noninvasive means to assess structural changes in injured central nervous system (CNS) tissue in humans over time. The few published in vivo MR imaging studies of spinal cord injury in rodent models by using field strengths < or = 7T suffer from low spatial resolution, flow, and motion artifacts. The aim of this study was to assess the capacity of a 17.6T imaging system to detect pathologic changes occurring in a rat spinal cord contusion injury model ex vivo and in vivo. METHODS Seven adult female Fischer 344 rats received contusion injuries at thoracic level T10, which caused severe and reproducible lesions of the injured spinal cord parenchyma. Two to 58 days postinjury, high-resolution MR imaging was performed ex vivo (2) or in vivo in anesthetized rats (5 spinal cord injured + one intact control animal) by using 2D multisection spin- and gradient-echo imaging sequences, respectively, combined with electrocardiogram triggering and respiratory gating. RESULTS The acquired images provided excellent resolution and gray/white matter differentiation without significant artifacts. Signal intensity changes, which were detected with ex vivo and in vivo MR imaging following spinal cord injury, could be correlated with histologically defined structural changes such as edema, fibroglial scar, and hemorrhage. CONCLUSIONS These results demonstrate that MR imaging at 17.6T allows high-resolution structural analysis of spinal cord pathology after injury.
Collapse
Affiliation(s)
- T Weber
- Department of Physics, EP5, University of Würzburg, Würzburg, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Sieland C, Stroh A, Faber C, Neuberger T, Weir K, Hild K, Mueller S, Lorenz P, Grune T, Jakob P, Taupitz M, Pilgrimm H, Schnorr J, Zimmer C. Detection of magnetically labelled embryonic stem cells in the rat brain by high resolution MR-Imaging in vivo. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-864008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
42
|
Fountoulakis M, Juranville JF, Jiang L, Avila D, Röder D, Jakob P, Berndt P, Evers S, Langen H. Depletion of the high-abundance plasma proteins. Amino Acids 2004; 27:249-59. [PMID: 15592754 DOI: 10.1007/s00726-004-0141-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2004] [Accepted: 10/04/2004] [Indexed: 10/26/2022]
Abstract
Body fluids, like plasma and urine, are comparatively easy to obtain and are useful for the detection of novel diagnostic markers by applying new technologies, like proteomics. However, in plasma, several high-abundance proteins are dominant and repress the signals of the lower-abundance proteins, which then become undetectable either by two-dimensional gels or chromatography. Therefore, depletion of the abundant proteins is a prerequisite for the detection of the low-abundance components. We applied affinity chromatography on blue matrix and Protein G and removed the most abundant human plasma proteins, albumin and the immunoglobulin chains. The plasma proteins, prior to albumin and immunoglobulin depletion, as well the eluates from the two chromatography steps were analyzed by two-dimensional electrophoresis and the proteins were identified by MALDI-TOF-MS. The analysis resulted in the identification of 83 different gene products in the untreated plasma. Removal of the high-abundance proteins resulted in the visualization of new protein signals. In the eluate of the two affinity steps, mostly albumin and immunoglobulin spots were detected but also spots representing several other abundant plasma proteins. The methodology is easy to perform and is useful as a first step in the detection of diagnostic markers in body fluids by applying proteomics technologies.
Collapse
Affiliation(s)
- M Fountoulakis
- F. Hoffmann-La Roche Ltd., Center of Medical Genomics, Basel, Switzerland.
| | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
The coverage regime just beyond 0.33 ML, representative of a perfectly ordered (square root 3 x square root 3)R30 degrees-CO layer on Ru(0001), has been investigated using infrared-absorption spectroscopy. Different isotopic mixtures of CO have been employed to derive a profound understanding of structural properties of such layers. It is found that extra CO molecules incorporated into the (square root 3 x square root 3)R30 degrees-CO layer affect their nearest neighbor molecules only, and the associated density gradient extends over no more than a few angstroms. Contrary to existing belief, the model system CO on Ru(0001) does not represent a case of an unusually shallow adsorption potential corrugation. Rather, CO experiences an exceptionally strong site preference when adsorbed on Ru(0001). Annealing causes the local distortion of the overlattice to propagate laterally, most probably in a density wave-like manner. Incipient motion on the atomic scale thereby has been detected by means of isotopic labeling of inequivalent molecules within the high density areas. All major conclusions are based on observations of (isotopically labeled) minority CO species which feature negligible dynamical lateral coupling. The majority CO species, on the other hand, provide laterally averaged, unspecific information on the status of the layer.
Collapse
Affiliation(s)
- P Jakob
- Physik-Department E20, Technische Universität München, 85747 Garching, Germany.
| |
Collapse
|
44
|
Wacker C, Fidler F, Dueren C, Jakob P, Bauer W. Quantitative Perfusionsbestimmung der Myokardperfusion mit der MRT ohne Kontrastmittel: erste Ergebnisse an Patienten mit koronarer Herzerkrankung. ROFO-FORTSCHR RONTG 2003. [DOI: 10.1055/s-2003-819904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
45
|
Schlapka A, Lischka M, Gross A, Käsberger U, Jakob P. Surface strain versus substrate interaction in heteroepitaxial metal layers: Pt on Ru(0001). Phys Rev Lett 2003; 91:016101. [PMID: 12906555 DOI: 10.1103/physrevlett.91.016101] [Citation(s) in RCA: 188] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2002] [Indexed: 05/24/2023]
Abstract
By studying the adsorption of CO on up to 30 layers of Pt deposited on Ru(0001) the influence of surface strain on the adsorption energy has been disentangled from the residual chemical interaction with the substrate. While the electronic influence of the substrate has largely vanished for three Pt layers, the effect of surface strain due to the 2.5% lattice mismatch of Pt and Ru remains initially intact and is only gradually released for n>/=5 Pt layers. Electronic structure calculations confirm the experimental observations, in particular, the dramatic decrease of the CO adsorption energy on a single Pt layer which is caused by the strong Pt-Ru interlayer coupling.
Collapse
Affiliation(s)
- A Schlapka
- Physik-Department, Technische Universität München, 85747 Garching, Germany
| | | | | | | | | |
Collapse
|
46
|
Kostov KL, Jakob P, Rauscher H, Menzel D. Interaction of carbon monoxide with atomic oxygen, atomic nitrogen, and nitric oxide on ruthenium (001): evidence for bridge-adsorbed carbon monoxide, site changes, and formation of isocyanate species. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100173a044] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
47
|
|
48
|
Jakob P. Investigation of one- and two-dimensional vibrational density of states using two-phonon infrared absorption spectroscopy. J Chem Phys 2001. [DOI: 10.1063/1.1343837] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
49
|
Abstract
Hemorrhage from the pancreatic duct, i.e. hemosuccus pancreaticus (HP), is a rare cause of gastrointestinal bleeding. Pancreatic hemosuccus is usually due to the rupture of an aneurysm of a visceral artery, most likely the splenic artery, in chronic pancreatitis. Other causes of HP are rare. We present a case of HP in a female patient with no history but with positive findings of chronic calcifying pancreatitis upon ultrasonographic investigation, computed tomography scan, and endoscopic retrograde cholangiopancreatography. With detectable fresh blood in the descending duodenum, angiography of the celiac artery revealed an aneurysm of the splenic artery as the suspected cause of intermittent bleeding from the pancreatic duct. The treatment is traditionally surgical or by interventional radiological means. This is the first case described in the literature in which interventional radiological therapy involved implantation of an uncoated metal Palmaz stent in the splenic artery. In the follow-up of 18 months no relapse of HP was observed.
Collapse
Affiliation(s)
- C A Benz
- Department of Gastroenterology, Klinikum der Stadt Ludwigshafen am Rhein, Academic Teaching Hospital of the University of Mainz, Germany.
| | | | | | | |
Collapse
|
50
|
Seelig MH, Berchtold C, Jakob P, Schönleben K. Contained rupture of an infrarenal abdominal aortic aneurysm treated by endoluminal repair. Eur J Vasc Endovasc Surg 2000; 19:202-4. [PMID: 10727372 DOI: 10.1053/ejvs.1999.0981] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- M H Seelig
- Department of Surgery, General Hospital Ludwigshafen, Bremserstrasse 79, Ludwigshafen am Rhein, D-67063, Germany
| | | | | | | |
Collapse
|