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Nikoubashman O, Wischer D, Hennemann HM, Büsen M, Brockmann C, Wiesmann M. Under Pressure: Comparison of Aspiration Techniques for Endovascular Mechanical Thrombectomy. AJNR Am J Neuroradiol 2018; 39:905-909. [PMID: 29650784 DOI: 10.3174/ajnr.a5605] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 01/31/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Blood flow should be interrupted during mechanical thrombectomy to prevent embolization of clot fragments. The purpose of our study was to provide a handy overview of the most common aspiration devices and to quantify their flow characteristics. MATERIALS AND METHODS We assessed volumetric flow rates generated by a 60-mL VacLok vacuum pressure syringe, a Pump MAX aspiration pump, and a Dominant Flex suction pump connected to the following: 1) an 8F long sheath, 2) an 8F balloon-guide catheter, 3) an ACE 64 distal aspiration catheter, and 4) an AXS Catalyst 6 Distal Access Catheter. We used a water/glycerol solution, which was kept at a constant temperature of 20°C (viscosity, 3.7 mPa · s). RESULTS Aspiration with the syringe and the Dominant Flex suction pump achieved the highest flows, whereas aspiration with the Pump MAX was significantly lower (P < .001). Resistors in the aspiration system (tubing, connectors, and so forth) restricted flows, especially when the resistance of the catheter was small (due to its large diameter) and the connected resistors became the predominant resistance (P < .001). The syringe achieved an average vacuum pressure of -90 kPa, and the resulting flow was constant during almost the entire procedure of filling the syringe. CONCLUSIONS Sixty-milliliter VacLok vacuum pressure syringes and the Dominant Flex suction pump achieved high and constant flows likely sufficient to reverse blood flow during thrombectomy with an 8F sheath or balloon-guide catheter in the ICA and modern distal aspiration catheters in the MCA. The Pump MAX aspiration pump is dedicated for use with distal aspiration catheters and is unlikely to reverse blood flow in the ICA and MCA without balloon protection.
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Affiliation(s)
- O Nikoubashman
- From the Department of Diagnostic and Interventional Neuroradiology (O.N., D.W., H.M.H., M.W.), RWTH Aachen University Hospital, Aachen, Germany
| | - D Wischer
- From the Department of Diagnostic and Interventional Neuroradiology (O.N., D.W., H.M.H., M.W.), RWTH Aachen University Hospital, Aachen, Germany
| | - H M Hennemann
- From the Department of Diagnostic and Interventional Neuroradiology (O.N., D.W., H.M.H., M.W.), RWTH Aachen University Hospital, Aachen, Germany
| | - M Büsen
- Institute of Applied Medical Engineering (M.B.), RWTH Aachen University, Aachen, Germany
| | - C Brockmann
- Department of Neuroradiology (C.B.), University Medical Centre, Johannes Gutenberg University, Mainz, Germany
| | - M Wiesmann
- From the Department of Diagnostic and Interventional Neuroradiology (O.N., D.W., H.M.H., M.W.), RWTH Aachen University Hospital, Aachen, Germany
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Kaymaz ZO, Nikoubashman O, Brockmann MA, Wiesmann M, Brockmann C. Influence of carotid tortuosity on internal carotid artery access time in the treatment of acute ischemic stroke. Interv Neuroradiol 2017; 23:583-588. [PMID: 28944705 DOI: 10.1177/1591019917729364] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Purpose Carotid artery anatomy is thought to influence internal carotid artery access time (ICA-AT) in patients requiring mechanical thrombectomy for acute ischemic stroke. This study investigates the association between ICA-AT and carotid anatomy. Material and methods Computed tomography angiography (CTA) data of 76 consecutive patients presenting with acute ischemic stroke requiring mechanical thrombectomy for middle cerebral artery or carotid T occlusion were evaluated. The supraaortic extracranial vasculature was analyzed regarding take-off angles and curvature of the affected side. Digital subtraction angiography data were primarily analyzed regarding ICA-AT and secondarily regarding recanalization time and radiographic result. Results ICA-AT was significantly influenced by vessel tortuosity. Take-off angle of the left common carotid artery ( p = 0.001) and the brachiocephalic trunk ( p = 0.002) as well as the tortuosity of the common carotid artery ( p = 0.002) had highest impact on ICA-AT. For recanalization time, however, we found only the take-off angle of the left common carotid artery to be of significance ( p = 0.020). There was a tendency for ICA-AT to correlate with successful (mTICI ≥ 2 b) revascularization (average time of successful results was 24.3 minutes, of unsuccessful was 35.6 minutes; p = 0.065). Every evaluated segment with less carotid tortuosity showed a carotid AT below 25 minutes. Conclusion Supraaortic vessel tortuosity significantly influences ICA-AT in mechanical thrombectomy for an acute large vessel. There furthermore was a trend for lower successful recanalization rates with increasing ICA-AT.
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Affiliation(s)
- Z O Kaymaz
- 1 Department of Diagnostic and Interventional Neuroradiology, 39058 University Hospital of the RWTH Aachen , Aachen, Germany.,2 Department of Neuroradiology, 9182 University Medical Center Mainz, Mainz , Germany
| | - O Nikoubashman
- 1 Department of Diagnostic and Interventional Neuroradiology, 39058 University Hospital of the RWTH Aachen , Aachen, Germany
| | - M A Brockmann
- 2 Department of Neuroradiology, 9182 University Medical Center Mainz, Mainz , Germany
| | - M Wiesmann
- 1 Department of Diagnostic and Interventional Neuroradiology, 39058 University Hospital of the RWTH Aachen , Aachen, Germany
| | - C Brockmann
- 2 Department of Neuroradiology, 9182 University Medical Center Mainz, Mainz , Germany
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Müller M, Brockmann C, Afat S, Nikoubashman O, Schubert GA, Reich A, Othman AE, Wiesmann M. Temporary Stent-Assisted Coil Embolization as a Treatment Option for Wide-Neck Aneurysms. AJNR Am J Neuroradiol 2017; 38:1372-1376. [PMID: 28473345 DOI: 10.3174/ajnr.a5204] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 02/22/2017] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND PURPOSE Simple coil embolization is often not a feasible treatment option in wide-neck aneurysms. Stent-assisted coil embolization helps stabilize the coils within the aneurysm. Permanent placement of a stent in an intracranial vessel, however, requires long-term platelet inhibition. Temporary stent-assisted coiling is an alternative technique for the treatment of wide-neck aneurysms. To date, only case reports and small case series have been published. Our purpose was to retrospectively analyze the effectiveness and safety of temporary stent-assisted coiling in a larger cohort. MATERIALS AND METHODS Research was performed for all patients who had undergone endovascular aneurysm treatment in our institution (University Hospital Aachen) between January 2010 and December 2015. During this period, 355 consecutive patients had undergone endovascular aneurysm treatment. We intended to treat 33 (9.2%) of them with temporary stent-assisted coiling, and they were included in this study. Incidental and acutely ruptured aneurysms were included. RESULTS Sufficient occlusion was achieved in 97.1% of the cases. In 94%, the stent could be fully recovered. Complications occurred in 5 patients (14.7%), whereas in only 1 case was the complication seen as specific to stent-assisted coiling. CONCLUSIONS Temporary stent-assisted coiling is an effective technique for the treatment of wide-neck aneurysms. Safety is comparable with that of stent-assisted coiling and coiling with balloon remodeling.
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Affiliation(s)
- M Müller
- From the Departments of Neuroradiology (M.M., C.B., S.A., O.N., M.W.)
| | - C Brockmann
- From the Departments of Neuroradiology (M.M., C.B., S.A., O.N., M.W.)
| | - S Afat
- From the Departments of Neuroradiology (M.M., C.B., S.A., O.N., M.W.)
| | - O Nikoubashman
- From the Departments of Neuroradiology (M.M., C.B., S.A., O.N., M.W.).,Institute of Neuroscience and Medicine 4 (O.N.), Forschungszentrum Jülich GmbH, Jülich, Germany
| | | | - A Reich
- Neurology (A.R.), University Hospital Aachen, Aachen, Germany
| | - A E Othman
- Department for Diagnostic and Interventional Radiology (A.E.O.), Eberhard Karls University Tuebingen, University Hospital Tuebingen, Tübingen, Germany
| | - M Wiesmann
- From the Departments of Neuroradiology (M.M., C.B., S.A., O.N., M.W.)
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Afat S, Brockmann C, Nikoubashman O, Müller M, Haberland U, Brockmann M, Nikolaou K, Wiesmann M, Othman A. Diagnostische Genauigkeit verschiedener Perfusionsalgorithmen zur Detektion zerebraler Vasospasmen. ROFO-FORTSCHR RONTG 2017. [DOI: 10.1055/s-0037-1600378] [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] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- S Afat
- Universitätsklinikum Aachen, Klinik für Diagnostische und Interventionelle Neuroradiologie, Aachen
| | - C Brockmann
- Universitätsklinikum Aachen, Klinik für Diagnostische und Interventionelle Neuroradiologie, Aachen
| | - O Nikoubashman
- Universitätsklinikum Aachen, Klinik für Diagnostische und Interventionelle Neuroradiologie, Aachen
| | - M Müller
- Universitätsklinikum Aachen, Klinik für Diagnostische und Interventionelle Neuroradiologie, Aachen
| | | | - M Brockmann
- Universitätsklinikum Mainz, Klinik und Poliklinik für Neuroradiologie, Mainz
| | - K Nikolaou
- Universitätsklinikum Tübingen, Diagnostische und Interventionelle Radiologie, Tübingen
| | - M Wiesmann
- Universitätsklinikum Aachen, Klinik für Diagnostische und Interventionelle Neuroradiologie, Aachen
| | - A Othman
- Universitätsklinikum Tübingen, Diagnostische und Interventionelle Radiologie, Tübingen
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Fokstuen S, Makrythanasis P, Hammar E, Guipponi M, Ranza E, Varvagiannis K, Santoni FA, Albarca-Aguilera M, Poleggi ME, Couchepin F, Brockmann C, Mauron A, Hurst SA, Moret C, Gehrig C, Vannier A, Bevillard J, Araud T, Gimelli S, Stathaki E, Paoloni-Giacobino A, Bottani A, Sloan-Béna F, Sizonenko LD, Mostafavi M, Hamamy H, Nouspikel T, Blouin JL, Antonarakis SE. Experience of a multidisciplinary task force with exome sequencing for Mendelian disorders. Hum Genomics 2016; 10:24. [PMID: 27353043 PMCID: PMC4924303 DOI: 10.1186/s40246-016-0080-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 06/17/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND In order to optimally integrate the use of high-throughput sequencing (HTS) as a tool in clinical diagnostics of likely monogenic disorders, we have created a multidisciplinary "Genome Clinic Task Force" at the University Hospitals of Geneva, which is composed of clinical and molecular geneticists, bioinformaticians, technicians, bioethicists, and a coordinator. METHODS AND RESULTS We have implemented whole exome sequencing (WES) with subsequent targeted bioinformatics analysis of gene lists for specific disorders. Clinical cases of heterogeneous Mendelian disorders that could potentially benefit from HTS are presented and discussed during the sessions of the task force. Debate concerning the interpretation of identified variants and the content of the final report constitutes a major part of the task force's work. Furthermore, issues related to bioethics, genetic counseling, quality control, and reimbursement are also addressed. CONCLUSIONS This multidisciplinary task force has enabled us to create a platform for regular exchanges between all involved experts in order to deal with the multiple complex issues related to HTS in clinical practice and to continuously improve the diagnostic use of HTS. In addition, this task force was instrumental to formally approve the reimbursement of HTS for molecular diagnosis of Mendelian disorders in Switzerland.
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Affiliation(s)
- S Fokstuen
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - P Makrythanasis
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva, 1 rue Michel-Servet, 1211, Geneva, Switzerland
| | - E Hammar
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - M Guipponi
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva, 1 rue Michel-Servet, 1211, Geneva, Switzerland
| | - E Ranza
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - K Varvagiannis
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva, 1 rue Michel-Servet, 1211, Geneva, Switzerland
| | - F A Santoni
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland.,Department of Genetic Medicine and Development, University of Geneva, 1 rue Michel-Servet, 1211, Geneva, Switzerland
| | - M Albarca-Aguilera
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - M E Poleggi
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - F Couchepin
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - C Brockmann
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - A Mauron
- Institute for Ethics, History, and the Humanities, Geneva University Medical School, Geneva, Switzerland
| | - S A Hurst
- Institute for Ethics, History, and the Humanities, Geneva University Medical School, Geneva, Switzerland
| | - C Moret
- Institute for Ethics, History, and the Humanities, Geneva University Medical School, Geneva, Switzerland
| | - C Gehrig
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - A Vannier
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - J Bevillard
- Department of Genetic Medicine and Development, University of Geneva, 1 rue Michel-Servet, 1211, Geneva, Switzerland
| | - T Araud
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - S Gimelli
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - E Stathaki
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - A Paoloni-Giacobino
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - A Bottani
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - F Sloan-Béna
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - L D'Amato Sizonenko
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - M Mostafavi
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - H Hamamy
- Department of Genetic Medicine and Development, University of Geneva, 1 rue Michel-Servet, 1211, Geneva, Switzerland
| | - T Nouspikel
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - J L Blouin
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - S E Antonarakis
- Service of Genetic Medicine, University Hospitals of Geneva, Geneva, Switzerland. .,Department of Genetic Medicine and Development, University of Geneva, 1 rue Michel-Servet, 1211, Geneva, Switzerland. .,iGE3, Institute of Genetics and Genomics of Geneva, Geneva, Switzerland.
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Othman AE, Afat S, Brockmann C, Nikoubashman O, Bier G, Brockmann MA, Nikolaou K, Tai JH, Yang ZP, Kim JH, Wiesmann M. Low-Dose Volume-Perfusion CT of the Brain: Effects of Radiation Dose Reduction on Performance of Perfusion CT Algorithms. Clin Neuroradiol 2015; 27:311-318. [PMID: 26669592 DOI: 10.1007/s00062-015-0489-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [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: 09/28/2015] [Accepted: 11/30/2015] [Indexed: 10/22/2022]
Abstract
PURPOSE We aimed to compare different computed tomography (CT) perfusion post-processing algorithms regarding image quality of perfusion maps from low-dose volume perfusion CT (VPCT) and their diagnostic performance regarding the detection of ischemic brain lesions. METHODS AND MATERIALS We included VPCT data of 21 patients with acute stroke (onset < 6h), which were acquired at 80 kV and 180 mAs. Low-dose VPCT datasets with 72 mAs (40 % of original dose) were generated using realistic low-dose simulation. Perfusion maps (cerebral blood volume (CBV); cerebral blood flow (CBF) from original and low-dose datasets were generated using two different commercially available post-processing methods: deconvolution-based method (DC) and maximum slope algorithm (MS). The resulting DC and MS perfusion maps were compared regarding perfusion values, signal-to-noise ratio (SNR) as well as image quality and diagnostic accuracy as rated by two blinded neuroradiologists. RESULTS Quantitative perfusion parameters highly correlated for both algorithms and both dose levels (r ≥ 0.613, p < 0.001). Regarding SNR levels and image quality of the CBV maps, no significant differences between DC and MS were found (p ≥ 0.683). Low-dose MS CBF maps yielded significantly higher SNR levels (p < 0.001) and quality scores (p = 0.014) than those of DC. Low-dose CBF and CBV maps from both DC and MS yielded high sensitivity and specificity for the detection of ischemic lesions (sensitivity ≥ 0.82, specificity ≥ 0.90). CONCLUSION Our results indicate that both methods produce diagnostically sufficient perfusion maps from simulated low-dose VPCT. However, MS produced CBF maps with significantly higher image quality and SNR than DC, indicating that MS might be more suitable for low-dose VPCT imaging.
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Affiliation(s)
- A E Othman
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany.,Department for Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076, Tübingen, Germany
| | - S Afat
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany
| | - C Brockmann
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany
| | - O Nikoubashman
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany
| | - G Bier
- Department for Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076, Tübingen, Germany
| | - M A Brockmann
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany
| | - K Nikolaou
- Department for Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076, Tübingen, Germany
| | - J H Tai
- Center for Medical-IT Convergence Technology Research, Advanced Institute of Convergence Technology, 433-270, Suwon, South Korea
| | - Z P Yang
- Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, 433-270, Suwon, South Korea
| | - J H Kim
- Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, 433-270, Suwon, South Korea. .,Department of Radiology, Seoul National University College of Medicine, 101 Daehak-Ro, Chongno-gu, 110-744, Seoul, South Korea. .,Center for Medical-IT Convergence Technology Research, Advanced Institute of Convergence Technology, 433-270, Suwon, South Korea.
| | - M Wiesmann
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074, Aachen, Germany
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Brockmann C, Dege S, Brockmann T, Kociok N, Strauß O, Joussen AM. Komplementsystem und Frühgeborenenretinopathie. Klin Monbl Augenheilkd 2015. [DOI: 10.1055/s-0035-1569212] [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]
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Brockmann T, Brockmann C, Maier AKB, Gundlach E, Schroeter J, Bertelmann E, Joussen AM, Torun N. Klinische Ergebnisse und histomorphologische Korrelate sekundärer Descemet's membrane endothelial keratoplasty (DMEK) bei Transplantatversagen nach Descemet's stripping endothelial keratoplasty (DSEK). Klin Monbl Augenheilkd 2014. [DOI: 10.1055/s-0034-1396484] [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: 10/24/2022]
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Brockmann C, Hager A, Rehak M, Seibel I, Riechardt AI, Joussen AM. Brachytherapie mittels Rutheniumapplikator bei vasoproliferativen retinalen Tumoren. Klin Monbl Augenheilkd 2014. [DOI: 10.1055/s-0034-1396477] [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: 10/24/2022]
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Brockmann C, Brockmann T, Vater A, Klussmann S, Dege S, Maier AK, Kociok N, Joussen AM. Inhibierung des Komplementfaktors C5a mittels Spiegelmeren im Mausmodell der Laser-induzierten choroidalen Neovaskularisation. Klin Monbl Augenheilkd 2013. [DOI: 10.1055/s-0033-1363413] [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]
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Brockmann T, Brockmann C, Maier AK, Schroeter J, Pleyer U, Bertelmann E, Joussen AM, Torun N. Pathomechanismen der Transplantatablösung nach Descemet's membrane endothelial keratoplasty (DMEK). Klin Monbl Augenheilkd 2013. [DOI: 10.1055/s-0033-1363399] [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]
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Waschkowski F, Brockmann C, Laube T, Mokwa W, Roessler G, Walter P. Development of a very large array for retinal stimulation. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2013:2748-51. [PMID: 24110296 DOI: 10.1109/embc.2013.6610109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Retina degeneration is one of the leading causes of blindness nowadays and cannot be cured in most cases. It has been shown that electrical stimulation of retinal ganglion cells can generate visual perceptions and therefore implantable electrode arrays can be possible treatment for these patients. Most implants developed for that purpose use electrode arrays with a size of a few millimeters squared and therefore could restore only a very small field of vision and hardly improve orientation in an unknown environment. In this paper we present results of the development of an implantable electrode array covering about 100 mm(2) of retinal tissue.
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Schulte B, John I, Simon B, Brockmann C, Oelmeier SA, Jahraus B, Kirchgessner H, Riplinger S, Carlomagno T, Wabnitz GH, Samstag Y. A reducing milieu renders cofilin insensitive to phosphatidylinositol 4,5-bisphosphate (PIP2) inhibition. J Biol Chem 2013; 288:29430-9. [PMID: 24003227 PMCID: PMC3795243 DOI: 10.1074/jbc.m113.479766] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Oxidative stress can lead to T cell hyporesponsiveness. A reducing micromilieu (e.g. provided by dendritic cells) can rescue T cells from such oxidant-induced dysfunction. However, the reducing effects on proteins leading to restored T cell activation remained unknown. One key molecule of T cell activation is the actin-remodeling protein cofilin, which is dephosphorylated on serine 3 upon T cell costimulation and has an essential role in formation of mature immune synapses between T cells and antigen-presenting cells. Cofilin is spatiotemporally regulated; at the plasma membrane, it can be inhibited by phosphatidylinositol 4,5-bisphosphate (PIP2). Here, we show by NMR spectroscopy that a reducing milieu led to structural changes in the cofilin molecule predominantly located on the protein surface. They overlapped with the PIP2- but not actin-binding sites. Accordingly, reduction of cofilin had no effect on F-actin binding and depolymerization and did not influence the cofilin phosphorylation state. However, it did prevent inhibition of cofilin activity through PIP2. Therefore, a reducing milieu may generate an additional pool of active cofilin at the plasma membrane. Consistently, in-flow microscopy revealed increased actin dynamics in the immune synapse of untransformed human T cells under reducing conditions. Altogether, we introduce a novel mechanism of redox regulation: reduction of the actin-remodeling protein cofilin renders it insensitive to PIP2 inhibition, resulting in enhanced actin dynamics.
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Affiliation(s)
- Bianca Schulte
- From the Institute for Immunology, Ruprecht Karls University, D-69120 Heidelberg, Germany
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Brockmann C, Brockmann T, Dawczynski J. Influence of seasonal sunlight intensity and iris color on the anti-VEGF therapy for neovascular age-related macular degeneration. Eye (Lond) 2013; 27:1169-73. [PMID: 23907626 DOI: 10.1038/eye.2013.159] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 06/27/2013] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To investigate the influence of seasonal light intensity and patients' iris color on the visual recovery after anti-vascular endothelial growth factor (VEGF) therapy with ranibizumab or bevacizumab for neovascular age-related macular degeneration (AMD). METHODS The visual acuity of 555 eyes (529 patients) with neovascular AMD was evaluated after intravitreal injections of either ranibizumab or bevacizumab in respect to global radiation intensity and iris color. RESULTS The functional results during anti-VEGF therapy revealed a seasonal oscillation with a negative correlation between visual recovery and global radiation intensity (R(2)=-0.756, P=0.004). Although the influence of the sunlight intensity on the visual recovery was significant after the first injection, this effect vanished within the continuous course of treatment. Regarding the improvement of functional recovery depending on iris color, dark-colored eyes (16.0%) gained 8.5 ± 10.0 letters after the first injection and 9.9 ± 12.8 letters after the second injection, compared with 3.4 ± 8.6 letters and 4.4 ± 11.0 letters in light-colored eyes (84.0%), respectively (P=0.005 and P=0.019). CONCLUSIONS Our results indicate that seasonal sunlight intensity and iris color might influence the visual recovery of neovascular AMD patients undergoing anti-VEGF therapy. Our findings may be used as suggestions to refine individual anti-VEGF therapy regimens, especially in patients with light-colored eyes.
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Affiliation(s)
- C Brockmann
- Department of Ophthalmology, Charité - University Medicine Berlin, Berlin, Germany
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Förster A, Nölte I, Wenz H, Al-Zghloul M, Kerl HU, Brockmann C, Brockmann MA, Groden C. Value of diffusion-weighted imaging in central pontine and extrapontine myelinolysis. Neuroradiology 2012; 55:49-56. [DOI: 10.1007/s00234-012-1083-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Accepted: 08/01/2012] [Indexed: 10/27/2022]
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16
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Brockmann C, Soucek S, Kuhlmann SI, Mills-Lujan K, Kelly SM, Yang JC, Iglesias N, Stutz F, Corbett AH, Neuhaus D, Stewart M. Structural basis for polyadenosine-RNA binding by Nab2 Zn fingers and its function in mRNA nuclear export. Structure 2012; 20:1007-18. [PMID: 22560733 PMCID: PMC3384006 DOI: 10.1016/j.str.2012.03.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 03/19/2012] [Accepted: 03/26/2012] [Indexed: 01/19/2023]
Abstract
Polyadenylation regulation and efficient nuclear export of mature mRNPs both require the polyadenosine-RNA-binding protein, Nab2, which contains seven CCCH Zn fingers. We describe here the solution structure of fingers 5-7, which are necessary and sufficient for high-affinity polyadenosine-RNA binding, and identify key residues involved. These Zn fingers form a single structural unit. Structural coherence is lost in the RNA-binding compromised Nab2-C437S mutant, which also suppresses the rat8-2 allele of RNA helicase Dbp5. Structure-guided Nab2 variants indicate that dbp5(rat8-2) suppression is more closely linked to hyperadenylation and suppression of mutant alleles of the nuclear RNA export adaptor, Yra1, than to affinity for polyadenosine-RNA. These results indicate that, in addition to modulating polyA tail length, Nab2 has an unanticipated function associated with generating export-competent mRNPs, and that changes within fingers 5-7 lead to suboptimal assembly of mRNP export complexes that are more easily disassembled by Dbp5 upon reaching the cytoplasm.
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Affiliation(s)
- Christoph Brockmann
- Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
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Menzel-Severing J, Laube T, Brockmann C, Bornfeld N, Mokwa W, Mazinani B, Walter P, Roessler G. Implantation and explantation of an active epiretinal visual prosthesis: 2-year follow-up data from the EPIRET3 prospective clinical trial. Eye (Lond) 2012; 26:501-9. [PMID: 22422033 DOI: 10.1038/eye.2012.35] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
PURPOSE The EPIRET3 retinal prosthesis was implanted in six volunteers legally blind from retinitis pigmentosa (RP) and removed after 4 weeks. Two years later, these subjects were re-examined to investigate ocular side effects and potential changes to quality of life. METHODS Vision-related quality of life was recorded using the NEI-VFQ-25 questionnaire. Clinical data including interval history, visual acuity, and intraocular pressure were obtained. Anterior and posterior segments of the study eyes were examined and photographed; this included fluorescein angiography and optical coherence tomography (OCT). RESULTS Data from five patients could be analysed. Life-quality score was consistent with results obtained at baseline. No unexpected structural alteration could be found in the study eyes. A moderate epiretinal gliosis was present in areas where the epiretinal stimulator had been fixated using retinal tacks. Angiography revealed no leakage or neovascularisation; OCT showed no generalised increase of central retinal thickness. CONCLUSIONS Vision-related quality of life is low in patients suffering from end-stage RP. No further deterioration of life quality could however be detected within our monitoring period. Surgery was well tolerated by both patients and their eyes, without adverse events occurring during the follow-up period. Epiretinal gliosis is known to occur with retinal tacks, but seems of no major concern to the integrity of the study eyes. However, it may potentially interfere with functional aspects of active implants. Hence, alternative, possibly biochemical, fixation methods merit further research.
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Affiliation(s)
- J Menzel-Severing
- Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
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18
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Jochum S, Brockmann C, Diehl S, Baake D, Obertacke U, Schoenberg S, Dinter D. Diagnostik relevanter kraniozervikaler Gefäßverletzungen in der Schockraum-CT. Unfallchirurg 2011. [DOI: 10.1007/s00113-010-1780-1] [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: 11/29/2022]
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19
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Brockmann C, Seker F, Weiss C, Groden C, Scharf J. Acetylsalicylic Acid Does Not Prevent Digital Subtraction Angiography-Related High Signal Intensity Lesions in Diffusion-Weighted Imaging in Cerebrovascular Patients. Clin Neuroradiol 2011; 22:15-20. [DOI: 10.1007/s00062-011-0076-3] [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] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 04/27/2011] [Indexed: 10/18/2022]
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20
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Jochum S, Brockmann C, Lederle K, Schönberg SO, Diehl SJ, Scharf J. Detektion von intrakraniellen Aneurysmen: Dual Energy CT versus DSA. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279477] [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: 10/18/2022]
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21
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Zaminer J, Brockmann C, Huy P, Opitz R, Reuter C, Beyermann M, Freund C, Müller M, Oschkinat H, Kühne R, Schmalz HG. Addressing protein-protein interactions with small molecules: a Pro-Pro dipeptide mimic with a PPII helix conformation as a module for the synthesis of PRD-binding ligands. Angew Chem Int Ed Engl 2011; 49:7111-5. [PMID: 20803590 DOI: 10.1002/anie.201001739] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jan Zaminer
- Universität zu Köln, Department für Chemie, Greinstrasse 4, 50939 Köln, Germany
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Schulze TJ, Weiß C, Luhm J, Brockmann C, Görg S, Hennig H. Preanalytical stability of HIV-1 and HCV RNA: impact of storage and plasma separation from cells on blood donation testing by NAT. Transfus Med 2010; 21:99-106. [DOI: 10.1111/j.1365-3148.2010.01051.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Brockmann C, Scharf J, Nölte IS, Seiz M, Groden C, Brockmann MA. Dual-energy CT after peri-interventional subarachnoid haemorrhage: a feasibility study. Clin Neuroradiol 2010; 20:231-5. [PMID: 21052614 DOI: 10.1007/s00062-010-0036-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [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: 01/27/2010] [Accepted: 09/13/2010] [Indexed: 11/26/2022]
Abstract
PURPOSE The aim was to assess the feasibility of dual-energy computed tomography (DE-CT) for detection of peri-interventional re-bleeding in patients with aneurysmal subarachnoid hemorrhage (re-SAH). METHODS For in vitro-analyses DE-CT of partially clotted blood intermixed with fresh blood containing contrast agent was performed. In a clinical setting, 4 patients routinely underwent DE-CT after suspected peri-interventional re-SAH. DE-CT source data images, iodine maps and virtual non-contrast images (VNC) were analyzed and regions-of-interest (ROI) measurements of density values were performed. RESULTS In vitro experiments demonstrated the feasibility of DE-CT to discriminate between blood with and without contrast agent. In all patients peri-interventional re-SAH was confirmed by detection of extravasated iodine within the subarachnoid spaces in post-interventional DE-CT. Dual-energy CT allowed the discrimination of old blood clots of the initial SAH and blood originating from peri-interventional re-SAH. After subtraction of the iodine-related high density signal, VNC images optimized the estimation of the true amount of subarachnoid blood. CONCLUSION Dual-energy CT allows the discrimination and subtraction of blood and iodine mixed within the subarachnoid spaces in patients with peri-interventional re-SAH. It helps to avoid overestimation of SAH after peri-interventional re-bleeding and therefore is a potentially valuable tool in the assessment of peri-interventional re-SAH.
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Affiliation(s)
- C Brockmann
- Department of Neuroradiology, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
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Brockmann C, Jochum S, Schoenberg SO, Diehl SJ. Dual energy CT Angiografie der Becken Bein Region bei peripherer Verschlusskrankheit. ROFO-FORTSCHR RONTG 2010. [DOI: 10.1055/s-0030-1268326] [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: 10/18/2022]
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Zaminer J, Brockmann C, Huy P, Opitz R, Reuter C, Beyermann M, Freund C, Müller M, Oschkinat H, Kühne R, Schmalz HG. Adressierung von Protein-Protein-Wechselwirkungen durch niedermolekulare Verbindungen: ein Pro-Pro-Dipeptidmimetikum mit PPII-Helixkonformation als Modul für die Synthese PRD-bindender Liganden. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201001739] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Zheng C, Fasken MB, Marshall NJ, Brockmann C, Rubinson ME, Wente SR, Corbett AH, Stewart M. Structural basis for the function of the Saccharomyces cerevisiae Gfd1 protein in mRNA nuclear export. J Biol Chem 2010; 285:20704-15. [PMID: 20463024 PMCID: PMC2898303 DOI: 10.1074/jbc.m110.107276] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 04/30/2010] [Indexed: 01/08/2023] Open
Abstract
Following transcription, mRNA is processed, packaged into messenger ribonucleoprotein (mRNP) particles, and transported through nuclear pores (NPCs) to the cytoplasm. At the NPC cytoplasmic face, Dbp5 mediates mRNP remodeling and mRNA export factor dissociation, releasing transcripts for translation. In Saccharomyces cerevisiae, the conserved poly(A) RNA-binding protein, Nab2, facilitates NPC targeting of transcripts and also modulates poly(A) tail length. Dbp5 removes Nab2 from mRNPs at the cytoplasmic face of the pore and, importantly, a Nab2 RNA-binding mutant suppresses the thermosensitive rat8-2 (dbp5) mutant. GFD1 is a multicopy suppressor of rat8-2 (dbp5), and Gfd1 interacts physically with both Dbp5 and the Nab2 N-terminal domain (Nab2-N). Here, we present a structural and functional analysis of the Gfd1/Nab2-N interaction. Crystallography, supported by solution NMR, shows that Gfd1 residues 126-150 form an alpha-helix when bound to Nab2-N. Engineered Nab2-N and Gfd1 mutants that inhibit this interaction in vitro were used to probe its function in vivo using the genetic interaction between GFD1 and NAB2. Although GFD1 is not essential for viability, its deletion severely impairs growth of rat8-2 (dbp5) cells. Moreover, although Gfd1 overexpression suppresses rat8-2 (dbp5), Gfd1 mutants that do not bind Nab2 only partially suppress rat8-2 (dbp5). Furthermore, rat8-2 (dbp5) cells that express nab2-Y34A, in which binding to Gfd1 is impaired, show a synthetic growth phenotype and nuclear accumulation of poly(A) RNA. These data support the importance of the Gfd1/Nab2 interaction for Dbp5 activity and provide further molecular details of the interactions that facilitate Dbp5-mediated mRNP remodeling in the terminal step of mRNA export.
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Affiliation(s)
- Chao Zheng
- From the MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, United Kingdom
| | - Milo B. Fasken
- the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Neil J. Marshall
- From the MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, United Kingdom
| | - Christoph Brockmann
- From the MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, United Kingdom
| | - Max E. Rubinson
- the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Susan R. Wente
- the Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Anita H. Corbett
- the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Murray Stewart
- From the MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, United Kingdom
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Eustermann S, Brockmann C, Mehrotra PV, Yang JC, Loakes D, West SC, Ahel I, Neuhaus D. Solution structures of the two PBZ domains from human APLF and their interaction with poly(ADP-ribose). Nat Struct Mol Biol 2010; 17:241-3. [PMID: 20098424 PMCID: PMC2912505 DOI: 10.1038/nsmb.1747] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Accepted: 11/17/2009] [Indexed: 12/24/2022]
Abstract
Addition of poly(ADP-ribose) (PAR) is an important post-translational modification in higher eukaryotes. Several DNA repair and checkpoint proteins possess specific PAR-binding zinc-finger (PBZ) modules critical for function. Here, we present solution structures of the two PBZ modules of aprataxin and PNK-like factor (APLF), revealing a novel type of zinc finger. By combining in vivo PAR-binding data with NMR interaction data using PAR fragments, we propose a structural basis for PBZ-PAR recognition.
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Hobeika M, Brockmann C, Gruessing F, Neuhaus D, Divita G, Stewart M, Dargemont C. Structural requirements for the ubiquitin-associated domain of the mRNA export factor Mex67 to bind its specific targets, the transcription elongation THO complex component Hpr1 and nucleoporin FXFG repeats. J Biol Chem 2009; 284:17575-83. [PMID: 19401465 DOI: 10.1074/jbc.m109.004374] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The ubiquitin-associated (UBA) domain of the principal Saccharomyces cerevisiae mRNA nuclear export factor, Mex67, can bind both nuclear pore protein (nucleoporin) FG repeats and Hpr1, a component of the TREX.THO complex that functions to link transcription and export. Using fluorescence resonance energy transfer-based assays, we show here that Hpr1 and the FG repeats interact with overlapping binding sites on the Mex67 UBA domain. We present the solution structure of the Mex67 UBA domain (UBA-Mex67) complexed with a FXFG nucleoporin peptide and define residues engaged in the interaction and those involved in the FXFG-induced conformational change. We show by NMR titration that the binding of Hpr1 produces analogous changes in chemical shifts in similar regions of the UBA domain. Together the data presented here indicate that both Hpr1 and FXFG nucleoporins may bind in a similar way to the UBA-Mex67 domain. However, whereas binding of Hpr1 allows UBA-Mex67 to interact with tetra-ubiquitin, the complex between UBA-Mex67 and FXFG is unable to bind mono- or tetra-ubiquitin, suggesting that both substrate binding and also the nature of the substrate may influence the affinity of the UBA-Mex67 domain for ubiquitin.
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Affiliation(s)
- Maria Hobeika
- Institut Jacques Monod, Université Paris VII, CNRS, 2 Place Jussieu, Tour 43, 75251 Paris Cedex 05, France
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29
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Jochum S, Brockmann C, Neff KW, Kilian AK, Schoenberg SO, Diehl S. Dual Energy CT in der Diagnostik der hirnversorgenden Gefäße: Vergleich von verschiedenen Postprocessing-Methoden zur Knochenentfernung. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1221386] [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]
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Brockmann C, Jochum S, Huck K, Ziegler P, Sadick M, Fink C, Schoenberg SO, Diehl S. Dual energy CT Angiographie der Becken Bein Region bei peripherer Verschlusskrankheit. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1221442] [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]
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31
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Doering T, Brockmann C, Wadle A, Hollenberg D, Förster T. Super mild oxidation coloring: preventing hair damage at the molecular level. Int J Cosmet Sci 2008. [DOI: 10.1111/j.1468-2494.2008.00430_4.x] [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: 11/26/2022]
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32
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Finke D, Hoerster R, Brockmann C, Kropf K, Hennig H, Zawatzky R, Goerg S. Interferon-α mRNA in Splenic CD11b+ Marginal Zone Macrophages of C4-Deficient Mice. Scand J Immunol 2008. [PMCID: PMC7169591 DOI: 10.1111/j.0300-9475.2004.01423am.x] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The absence of early complement components (C1, C4 and C2 but not C3) is a predisposing factor for systemic lupus erythematosus (SLE). Recently, we demonstrated that, in C4‐deficient (C4 def.) mice, IgM‐containing immune complexes (IgM‐IC) are filtered by the splenic barrier of marginal zone macrophages (MZM), resulting in an increased immune response against antigens within these IgM‐IC, but this could not be observed in wildtype or C3 def. mice. We hypothesized that splenic CD11b+ MZM play an important role in the induction of autoimmunity, and we therefore analysed their cytokine profile after isolation with the help of magnetic antibody cell sorting. mRNA was isolated, and real‐time PCR was performed with specific primers for murine IFN‐γ (IFN‐γ), interleukin‐12 (IL‐12) and IFN‐α (IFN‐α). We observe a moderate increase of IL‐12 and IFN‐γ mRNA in CD11b+ cells of C4 def. mice compared to wildtype cells. Surprisingly, the concentration of IFN‐α mRNA is six times higher in C4 def. mice. Preliminary results suggest that mRNA in CD11b+ cells of C3 def. mice is even lower than that in wt. Six hours following i.v. application of 20 µg of a murine monoclonal IgM anti‐dsDNA antibody, production of IL‐12, IFN‐γ and IFN‐α mRNA is increased in CD11b+ cells of both C4 def. and wt mice. Several references described increased levels of INF‐α in patients with SLE. Dendritic cells are discussed as a major source of IFN‐α. Our observation that C4‐deficient, SLE‐susceptible mice demonstrate an increased spontaneous IFN‐α production by splenic CD11b+ marginal zone macrophages could be an early sign and a trigger for the development of SLE. This is supported by the fact that the absence of C3 is not a predisposing factor for SLE and our observation that C3 def. animals display low levels of IFN‐α mRNA.
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Affiliation(s)
- D. Finke
- Institute for Immunology and Transfusion Medicine, University of Luebeck, Luebeck, and
| | - R. Hoerster
- Institute for Immunology and Transfusion Medicine, University of Luebeck, Luebeck, and
| | - C. Brockmann
- Institute for Immunology and Transfusion Medicine, University of Luebeck, Luebeck, and
| | - K. Kropf
- Institute for Immunology and Transfusion Medicine, University of Luebeck, Luebeck, and
| | - H. Hennig
- Institute for Immunology and Transfusion Medicine, University of Luebeck, Luebeck, and
| | - R. Zawatzky
- Department of Tumorvirus‐Immunology, German Cancer Research Centre, Heidelberg, Germany. E‐mail:
| | - S. Goerg
- Institute for Immunology and Transfusion Medicine, University of Luebeck, Luebeck, and
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Dowler EF, Diehl A, Schmieder P, Brockmann C, Elkins J, Soundararajan M, Oschkinat H, Ball LJ. Backbone and sidechain 1H, 13C and 15N resonance assignments of the RGS domain from human RGS14. Biomol NMR Assign 2007; 1:95-97. [PMID: 19636837 DOI: 10.1007/s12104-007-9029-9] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2007] [Accepted: 06/09/2007] [Indexed: 05/28/2023]
Abstract
We have assigned 1H, 13C and 15N resonances of the RGS domain from the human RGS14 protein, a multi-domain member of the RGS (Regulators of G-protein signalling) family of proteins, important in the down-regulation of specific G-protein signalling pathways.
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Affiliation(s)
- Elizabeth F Dowler
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Robert-Rössle-Str. 10, 13125 Berlin, Germany.
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Hobeika M, Brockmann C, Iglesias N, Gwizdek C, Neuhaus D, Stutz F, Stewart M, Divita G, Dargemont C. Coordination of Hpr1 and ubiquitin binding by the UBA domain of the mRNA export factor Mex67. Mol Biol Cell 2007; 18:2561-8. [PMID: 17475778 PMCID: PMC1924821 DOI: 10.1091/mbc.e07-02-0153] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The ubiquitin-associated (UBA) domain of the mRNA nuclear export receptor Mex67 helps in coordinating transcription elongation and nuclear export by interacting both with ubiquitin conjugates and specific targets, such as Hpr1, a component of the THO complex. Here, we analyzed substrate specificity and ubiquitin selectivity of the Mex67 UBA domain. UBA-Mex67 is formed by three helices arranged in a classical UBA fold plus a fourth helix, H4. Deletion or mutation of helix H4 strengthens the interaction between UBA-Mex67 and ubiquitin, but it decreases its affinity for Hpr1. Interaction with Hpr1 is required for Mex67 UBA domain to bind polyubiquitin, possibly by inducing an H4-dependent conformational change. In vivo, deletion of helix H4 reduces cotranscriptional recruitment of Mex67 on activated genes, and it also shows an mRNA export defect. Based on these results, we propose that H4 functions as a molecular switch that coordinates the interaction of Mex67 with ubiquitin bound to specific substrates, defines the selectivity of the Mex67 UBA domain for polyubiquitin, and prevents its binding to nonspecific substrates.
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Affiliation(s)
- Maria Hobeika
- Institut Jacques Monod, Universités Paris VI and VII, Centre National de la Recherche Scientifique, 75251 Paris Cedex 05, France
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Brockmann C, Diehl A, Rehbein K, Strauss H, Schmieder P, Korn B, Kühne R, Oschkinat H. The oxidized subunit B8 from human complex I adopts a thioredoxin fold. Structure 2005; 12:1645-54. [PMID: 15341729 DOI: 10.1016/j.str.2004.06.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [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: 04/08/2004] [Revised: 05/28/2004] [Accepted: 06/22/2004] [Indexed: 11/27/2022]
Abstract
Subunit B8 from ubiquinone oxidoreductase (complex I) (CI-B8) is one of several nuclear-encoded supernumerary subunits that are not present in bacterial complex I. Its solution structure shows a thioredoxin fold with highest similarities to the human thioredoxin mutant C73S and thioredoxin 2 from Anabeana sp. Interestingly, these proteins contain active sites in the same area, where the disulfide bond of oxidized CI-B8 is located. The redox potential of this disulfide bond is -251.6 mV, comparing well to that of disulfides in other thioredoxin-like proteins. Analysis of the structure reveals a surface area that is exclusively composed of highly conserved residues and thus most likely a subunit interaction site within complex I.
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Waldmann H, Karaguni IM, Carpintero M, Gourzoulidou E, Herrmann C, Brockmann C, Oschkinat H, Müller O. Sulindac-derived Ras pathway inhibitors target the Ras-Raf interaction and downstream effectors in the Ras pathway. Angew Chem Int Ed Engl 2004; 43:454-8. [PMID: 14735533 DOI: 10.1002/anie.200353089] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Herbert Waldmann
- Max-Planck-Institut für molekulare Physiologie, Abteilung Chemische Biologie, Dortmund, Germany
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Waldmann H, Karaguni IM, Carpintero M, Gourzoulidou E, Herrmann C, Brockmann C, Oschkinat H, Müller O. Sulindac-Derived Ras Pathway Inhibitors Target the Ras–Raf Interaction and Downstream Effectors in the Ras Pathway. Angew Chem Int Ed Engl 2004. [DOI: 10.1002/ange.200353089] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Brockmann C, Leitner D, Labudde D, Diehl A, Sievert V, Büssow K, Kühne R, Oschkinat H. The solution structure of the SODD BAG domain reveals additional electrostatic interactions in the HSP70 complexes of SODD subfamily BAG domains. FEBS Lett 2004; 558:101-6. [PMID: 14759524 DOI: 10.1016/s0014-5793(03)01490-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [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: 11/12/2003] [Revised: 12/08/2003] [Accepted: 12/10/2003] [Indexed: 10/26/2022]
Abstract
The solution structure of an N-terminally extended construct of the SODD BAG domain was determined by nuclear magnetic resonance spectroscopy. A homology model of the SODD-BAG/HSP70 complex reveals additional possible interactions that are specific for the SODD subfamily of BAG domains while the overall geometry of the complex remains the same. Relaxation rate measurements show that amino acids N358-S375 of SODD which were previously assigned to its BAG domain are not structured in our construct. The SODD BAG domain is thus indeed smaller than the homologous domain in Bag1 defining a new subfamily of BAG domains.
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Affiliation(s)
- Christoph Brockmann
- Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, D-13125 Berlin, Germany
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Pires JR, Hong X, Brockmann C, Volkmer-Engert R, Schneider-Mergener J, Oschkinat H, Erdmann R. The ScPex13p SH3 domain exposes two distinct binding sites for Pex5p and Pex14p. J Mol Biol 2003; 326:1427-35. [PMID: 12595255 DOI: 10.1016/s0022-2836(03)00039-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [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: 11/20/2022]
Abstract
Pex13p is an essential component of the peroxisomal protein import machinery and interacts via its C-terminal SH3 domain with the type II SH3-ligand Pex14p and the non-PXXP protein Pex5p. We report the solution structure of the SH3 domain of Pex13p from Saccharomyces cerevisiae and the identification of a novel-binding pocket, which binds a non-PXXP-peptide representing the binding site of Pex5p. Chemical shift assays revealed the binding sites for Pex5p and Pex14p ligand peptides to be distinct and spatially separated. Competition assays demonstrated that the two ligand peptides can bind simultaneously to the SH3 domain.
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Affiliation(s)
- José R Pires
- Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125, Berlin, Germany
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Sauma A, Quiroga R, Brockmann C, Montaño M, Flores G, Barrenechea JP. Successful replantation following an accidental forearm amputation. Case report and review of the literature. Acta Chir Belg 2002; 102:126-30. [PMID: 12051086 DOI: 10.1080/00015458.2002.11679279] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We report a patient who suffered an accidental complete amputation of the right forearm followed by a successful replantation and comment on the indications and management of macro-replantations of the upper limbs. This is the first time that a successful surgical procedure of this nature has been performed in Bolivia, with no post-operative complications and excellent long-term functional recovery.
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Affiliation(s)
- A Sauma
- Department of Surgery and Unit of Physical Therapy, Centro Médico Quirúrgico Boliviano Belga, Cochabamba, Bolivia
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Blaszczyk A, Brockmann C, Grifo J, Krey L. Cell cycle checkpoint proteins Bub1 and Mad2 localize to kinetochores during meiosis in mouse oocytes. Fertil Steril 2001. [DOI: 10.1016/s0015-0282(01)02782-0] [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: 11/26/2022]
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Brockmann C, Mummert R, Ruhberg H, Storch V. The female genital system of Ooperipatellus decoratus (Onychophora, Peripatopsidae): an ultrastructural study. J Morphol 2001; 249:77-88. [PMID: 11466737 DOI: 10.1002/jmor.1041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 11/12/2022]
Abstract
The female genital system of the oviparous peripatopsid Ooperipatellus decoratus consists of an ovary, oviducts equipped with receptacula seminis and additional pouches, uteri, and a vagina. It is examined using transmission and scanning electron microscopy. The ovary is made up of paired ovarian tubes united anteriorly and posteriorly and differentiated into a sterile dorsal part and a fertile ventral part with exogenous oocytes. Fertilization presumably occurs in the oviducts once the oocytes pass the receptaculum seminis. Although the receptacula seminis have been reported to occur in juvenile O. decoratus females only, the present study reveals that they are present in adult females as well. Their wall consists of a cuboidal epithelium covered with a thin collagen-muscle layer. The additional pouches are projections of the oviducts facing the receptacula seminis. They are distally closed to the haemocoel by a flattened epithelium and lack external muscle cells. A thin collagen layer is only found proximally. The uteri are characterized by a columnar epithelium with folded cell membranes allowing extension of the uteri, thus facilitating the passage of the large uterine eggs towards the vagina. Another dominating feature of the uteri is a distally increasing secretory production, which probably contributes to chorion development. Cilia occurring along the entire length of the uteri are considered to assist in the transport of eggs towards the vagina.
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Affiliation(s)
- C Brockmann
- Zoologisches Institut und Zoologisches Museum, Universität Hamburg, Hamburg, Germany.
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Brockmann C, Raasch W, Bastian C. [Endocrine stress parameters during TIVA with remifentanil or sufentanil]. Anasthesiol Intensivmed Notfallmed Schmerzther 2000; 35:685-91. [PMID: 11130129 DOI: 10.1055/s-2000-8163] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [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: 10/17/2022]
Abstract
OBJECTIVE Increases of heart rate and blood pressure during anaesthesia are interpreted as a response to surgical stimulation, although the endocrine response and the cardiovascular reaction can differ markedly. We compared remifentanil and sufentanil as part of a TIVA for retinal surgery with respect to the endocrine stress responses and haemodynamic reactions. METHODS After ethics committee approval and informed consent, 22 patients (ASA I-III) scheduled for retinal surgery were included in this patient-blind, randomized, prospective parallel-group study and allocated to one of the two groups receiving TIVA with propofol (4 mg/kg/h) and remifentanil (R-group) 0.25 microgram/kg/min, or sufentanil (S-group) 1 microgram/kg before surgery with dosage adjustments according to haemodynamic parameters. Prolactin, growth hormone, cortisol, epinephrine and norepinephrine were measured 60 min before anaesthesia, 30 min after start of surgery and 30 min after extubation. RESULTS (Significance level: P < 0.05) Only prolactin increased significantly in both groups during the surgical procedure, the S-group showing a greater increase than the R-group. Cortisol and norepinephrine concentrations decreased during surgery in both groups significantly. Growth hormone and epinephrine concentrations only decreased in the S-group during operation while there was no significant change in the R-group. The blood pressure dropped by about 30% in both groups intraoperatively while there was a tendency towards lower heart rates in the R-group with 58/min vs. 64/min in the S-group (mean). CONCLUSION The increase of prolactin concentrations could be interpreted as a result of the stimulation of mu 1-receptors. As all other measured stress hormones did not increase in both groups, remifentanil and sufentanil both provide an effective suppression of noxious stimulation induced endocrine response.
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Affiliation(s)
- C Brockmann
- Klinik für Anästhesiologie, Medizinischen Universität zu Lübeck
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Brockmann C, Blaszczyk A, Ostrer H, Grifo J, Krey L. Immunocytochemical Localization of Synaptonemal Complex Proteins in Mouse Oocytes. Fertil Steril 2000. [DOI: 10.1016/s0015-0282(00)01086-4] [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: 10/18/2022]
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Blaszczyk A, Brockmann C, Grifo J, Krey L. Identification and Localization of Cell Cycle Proteins Implicated in Mammalian Oocyte Maturation. Fertil Steril 2000. [DOI: 10.1016/s0015-0282(00)01284-x] [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: 11/28/2022]
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Pompilio G, Brockmann C, Bruneau M, Buche M, Amrani M, Louagie Y, Eucher P, Rubay J, Jamart J, Dion R, Schoevaerdts JC. Long-term survival after aortic valve replacement for native active infective endocarditis. Cardiovasc Surg 1998; 6:126-32. [PMID: 9610824 DOI: 10.1016/s0967-2109(97)00139-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The objective of this study was to analyse the impact of acute surgery for native aortic valve endocarditis and its influence on the long-term prognosis after surgery. METHODS A total of 161 patients underwent aortic valve replacement for native active aortic valve endocarditis (NAAVE) during a 29-year period, from 1967 to 1995 (age range: 10 to 72 years; mean 48 +/- 12). The main indication for surgery was progressive congestive heart failure (76%). Other indications were untreatable sepsis (27%), peripheral or central emboli (12%) and, from 1978, echocardiographic evidence of friable, pedunculated vegetations (3%). Streptococcal and staphylococcal infections predominated. Concomitant procedures were performed in 27% of the patients, including mitral and tricuspid valve surgery and coronary bypass procedures. RESULTS Operative mortality was 8% in the majority of cases caused by heart failure or multi-organ failure. Multivariate logistic regression analysis identified NYHA class IV to be an independent predictor for postoperative death. Long-term survival for discharged patients was 75% at 10 years and 58% at 15 years, with a mortality rate of 3.6%/patient/year. Cox regression analysis identified the year of operation, trivalvular endocarditis and staphylococcal infection as independent predictors of survival. At 10 and 15 years after aortic valve replacement, 91% and 84% of the patients, respectively, were free of recurrent endocarditis. The presence of an abscess cavity at first operation was found to be predictive of recurrent endocarditis. CONCLUSIONS Valve replacement for NAAVE offers a good chance for a cure and satisfactory long-term survival. Improvements in pre- and per-operative management of the very ill patient, and the use of allograft valves are likely to further improve long-term results. Finally, the presence of staphylococcal endocarditis requires long-term postoperative antibiotic therapy.
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Affiliation(s)
- G Pompilio
- Department of Cardiovascular and Thoracic Surgery, Clinics of the Catholic University of Louvain (UCL), Brussels, Belgium
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Fahrbach E, Brockmann C, Meincke J. Horizontal mixing in the Atlantic Equatorial Undercurrent estimated from drifting buoy clusters. ACTA ACUST UNITED AC 1986. [DOI: 10.1029/jc091ic09p10557] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fahrbach E, Brockmann C, Lostaunau N, Urquizo W. The Northern Peruvian Upwelling System during the ESACAN experiment. Coastal Upwelling 1981. [DOI: 10.1029/co001p0134] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Brockmann C. An assistive device for a forearm crutch. Phys Ther 1969; 49:50. [PMID: 5803915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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