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Lücke J, Böttcher M, Nawrocki M, Meins N, Schnell J, Heinrich F, Bertram F, Sabihi M, Seeger P, Pfaff M, Notz S, Blankenburg T, Zhang T, Kempski J, Reeh M, Wolter S, Mann O, Lütgehetmann M, Hackert T, Izbicki JR, Duprée A, Huber S, Ondruschka B, Giannou AD. Obesity and diabetes mellitus are associated with SARS-CoV-2 outcomes without influencing signature genes of extrapulmonary immune compartments at the RNA level. Heliyon 2024; 10:e24508. [PMID: 38298642 PMCID: PMC10828091 DOI: 10.1016/j.heliyon.2024.e24508] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 01/04/2024] [Accepted: 01/10/2024] [Indexed: 02/02/2024] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which is responsible for eliciting Coronavirus disease 2019 (COVID-19) still challenges healthcare services worldwide. While many patients only suffer from mild symptoms, patients with some pre-existing medical conditions are at a higher risk for a detrimental course of disease. However, the underlying mechanisms determining disease course are only partially understood. One key factor influencing disease severity is described to be immune-mediated. In this report, we describe a post-mortem analysis of 45 individuals who died from SARS-CoV-2 infection. We could show that although sociodemographic factors and premedical conditions such as obesity and diabetes mellitus reduced survival time in our cohort, they were not associated with changes in the expression of immune-related signature genes at the RNA level in the blood, the gut, or the liver between these different groups. Our data indicate that obesity and diabetes mellitus influence SARS-CoV-2-related mortality, without influencing the extrapulmonary gene expression of immunity-related signature genes at the RNA level.
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Affiliation(s)
- Jöran Lücke
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Marius Böttcher
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Mikolaj Nawrocki
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Nicholas Meins
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Josa Schnell
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Fabian Heinrich
- Institute of Legal Medicine, University Medical Center Hamburg-Eppendorf, Butenfeld 34, 22529, Hamburg, Germany
- Institute of Medical Microbiology, Virology, and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Franziska Bertram
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Institute of Medical Microbiology, Virology, and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Morsal Sabihi
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Philipp Seeger
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Marie Pfaff
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Sara Notz
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Tom Blankenburg
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Tao Zhang
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Jan Kempski
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- The Calcium Signaling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Matthias Reeh
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Stefan Wolter
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Oliver Mann
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Marc Lütgehetmann
- Institute of Medical Microbiology, Virology, and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thilo Hackert
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Jakob R. Izbicki
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Anna Duprée
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Samuel Huber
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Benjamin Ondruschka
- Institute of Legal Medicine, University Medical Center Hamburg-Eppendorf, Butenfeld 34, 22529, Hamburg, Germany
| | - Anastasios D. Giannou
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
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Lücke J, Nawrocki M, Schnell J, Meins N, Heinrich F, Zhang T, Bertram F, Sabihi M, Böttcher M, Blankenburg T, Pfaff M, Notz S, Kempski J, Reeh M, Wolter S, Mann O, Izbicki JR, Lütgehetmann M, Duprée A, Giannou AD, Ondruschka B, Huber S. TNFα aggravates detrimental effects of SARS-CoV-2 infection in the liver. Front Immunol 2023; 14:1151937. [PMID: 37063909 PMCID: PMC10102423 DOI: 10.3389/fimmu.2023.1151937] [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] [Received: 01/27/2023] [Accepted: 03/14/2023] [Indexed: 04/03/2023] Open
Abstract
Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus does not only lead to pulmonary infection but can also infect other organs such as the gut, the kidney, or the liver. Recent studies confirmed that severe cases of COVID-19 are often associated with liver damage and liver failure, as well as the systemic upregulation of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNFα). However, the impact these immune mediators in the liver have on patient survival during SARS-CoV-2 infection is currently unknown. Here, by performing a post-mortem analysis of 45 patients that died from a SARS-CoV-2 infection, we find that an increased expression of TNFA in the liver is associated with elevated mortality. Using publicly available single-cell sequencing datasets, we determined that Kupffer cells and monocytes are the main sources of this TNFα production. Further analysis revealed that TNFα signaling led to the upregulation of pro-inflammatory genes that are associated with an unfavorable outcome. Moreover, high levels of TNFA in the liver were associated with lower levels of interferon alpha and interferon beta. Thus, TNFα signaling in the infected SARS-CoV-2 liver correlates with reduced interferon levels and overall survival time.
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Affiliation(s)
- Jöran Lücke
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- *Correspondence: Samuel Huber, ; Jöran Lücke,
| | - Mikolaj Nawrocki
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Josa Schnell
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nicholas Meins
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fabian Heinrich
- Institute of Legal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Medical Microbiology, Virology, and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tao Zhang
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Franziska Bertram
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Medical Microbiology, Virology, and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Morsal Sabihi
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marius Böttcher
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tom Blankenburg
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marie Pfaff
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sara Notz
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jan Kempski
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- The Calcium Signaling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Matthias Reeh
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan Wolter
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Oliver Mann
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jakob R. Izbicki
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marc Lütgehetmann
- Institute of Medical Microbiology, Virology, and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anna Duprée
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anastasios D. Giannou
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Benjamin Ondruschka
- Institute of Legal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Samuel Huber
- Section of Molecular Immunology and Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Hamburg Center for Translational Immunology (HCTI), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- *Correspondence: Samuel Huber, ; Jöran Lücke,
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Weber A, Schmidt V, Leuders P, Pfaff M, Hesse J, Schrader J, Lichtenberg A, Akhyari P. Dysregulation of ATPases Promotes the Degeneration of Aortic Valves. Thorac Cardiovasc Surg 2020. [DOI: 10.1055/s-0040-1705464] [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: 10/24/2022]
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Weller K, Woetzel D, Guthke R, Schroeder K, Stein G, Pohlmeier R, Vienken J, Pfaff M. Prediction of Cardiovascular Risk in Hemodialysis Patients by Data Mining. Methods Inf Med 2018. [DOI: 10.1055/s-0038-1633845] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Summary
Objectives:
The objective of this work was to contribute to the development, validation and application of data mining methods for prediction in decision support systems in medicine. The particular focus was on the prediction of cardiovascular risk factors in hemodialysis patients, specifically the interventricular septum (IVS) thickness of the heart of individual patients as an important quantitative indicator to diagnose left ventricular hypertrophy. The work was based on data from 63 long-term hemodialysis patients of the KfH Dialysis Centre in Jena, Germany.
Methods:
The approach applied is based on data mining methods and involves four major steps: data based clustering, cluster based rule extraction, rulebase construction and cluster and rule based prediction. The methods employed include crisp and fuzzy algorithms. At each step, logical and medical validation of results was carried out. Different sets of randomly selected patient data were used to train, test and optimize the clusterbases and rulebases for prediction.
Results:
Using the best clusterbase/rulebase combination designed, the IVS thickness cluster (‘small’ or ‘large’) was predicted correctly for 30 of the 35 patients with known IVS values in the training data set; no patient was predicted incorrectly and 5 were parity predicted. For the test data set, 4 of the 6 patients with known IVS values were predicted correctly, no patient incorrectly and 2 parity. These results did not substantially differ from those obtained using the second best clusterbase/rulebase combination which was finally recommended for use based on further performance criteria. The prediction of the IVS thickness clusters of the 22 patients with unknown IVS values also yielded good results that were (and could only be) validated by a medical individual risk assessment of these patients.
Conclusions:
The approach applied proved successful for the cluster and rule based prediction of a quantitative variable, such as IVS thickness, for individual patients from other variables relevant to the problem. The results obtained demonstrate the high potential of the approach and the methods developed and validated to support decision-making in hemodialysis and other fields of medicine by individual risk prediction.
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Weber A, Pfaff M, Barth M, Lichtenberg A, Akhyari P. Role of VEGF Receptors in the Degeneration Process of Aortic Valves. Thorac Cardiovasc Surg 2018. [DOI: 10.1055/s-0038-1627846] [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: 10/28/2022]
Affiliation(s)
- A. Weber
- Department of Cardiovascular Surgery, Experimental Surgery, Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
| | - M. Pfaff
- Department of Cardiovascular Surgery, Experimental Surgery, Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
| | - M. Barth
- Department of Cardiovascular Surgery, Experimental Surgery, Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
| | - A. Lichtenberg
- Department of Cardiovascular Surgery, Experimental Surgery, Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
| | - P. Akhyari
- Department of Cardiovascular Surgery, Experimental Surgery, Heinrich Heine University, Medical Faculty, Düsseldorf, Germany
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Bachmaier A, Aboulfadl H, Pfaff M, Mücklich F, Motz C. Structural evolution and strain induced mixing in Cu-Co composites studied by transmission electron microscopy and atom probe tomography. Mater Charact 2015; 100:178-191. [PMID: 26523113 PMCID: PMC4600609 DOI: 10.1016/j.matchar.2014.12.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 12/19/2014] [Accepted: 12/23/2014] [Indexed: 06/05/2023]
Abstract
A Cu-Co composite material is chosen as a model system to study structural evolution and phase formations during severe plastic deformation. The evolving microstructures as a function of the applied strain were characterized at the micro-, nano-, and atomic scale-levels by combining scanning electron microscopy and transmission electron microscopy including energy-filtered transmission electron microscopy and electron energy-loss spectroscopy. The amount of intermixing between the two phases at different strains was examined at the atomic scale using atom probe tomography as complimentary method. It is shown that Co particles are dissolved in the Cu matrix during severe plastic deformation to a remarkable extent and their size, number, and volume fraction were quantitatively determined during the deformation process. From the results, it can be concluded that supersaturated solid solutions up to 26 at.% Co in a fcc Cu-26 at.% Co alloy are obtained during deformation. However, the distribution of Co was found to be inhomogeneous even at the highest degree of investigated strain.
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Affiliation(s)
- A. Bachmaier
- Chair of Materials Science and Methods, Saarland University, Saarbrücken, Germany
| | - H. Aboulfadl
- Chair of Functional Materials, Saarland University, Saarbrücken, Germany
| | - M. Pfaff
- INM-Leibniz Institute for New Materials, Saarbrücken, Germany
| | - F. Mücklich
- Chair of Functional Materials, Saarland University, Saarbrücken, Germany
| | - C. Motz
- Chair of Materials Science and Methods, Saarland University, Saarbrücken, Germany
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Fedtke A, Pfaff M, Volquardsen J, Venner M, Vervuert I. Effects of feeding different roughage-based diets on gastric mucosa after weaning in warmblood foals. PFERDEHEILKUNDE 2015. [DOI: 10.21836/pem20150607] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Shah A, Pfaff M, Wu W, Steinbacher D. Abstract 13. Plast Reconstr Surg 2013. [DOI: 10.1097/01.prs.0000429958.10423.49] [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: 11/25/2022]
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9
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Pfaff M, Müller E, Klein MFG, Colsmann A, Lemmer U, Krzyzanek V, Reichelt R, Gerthsen D. Low-energy electron scattering in carbon-based materials analyzed by scanning transmission electron microscopy and its application to sample thickness determination. J Microsc 2010; 243:31-9. [PMID: 21155995 DOI: 10.1111/j.1365-2818.2010.03475.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
High-angle annular dark-field scanning transmission electron microscopy (HAADF STEM) at low energies (≤30 keV) was used to study quantitatively electron scattering in amorphous carbon and carbon-based materials. Experimental HAADF STEM intensities from samples with well-known composition and thickness are compared with results of Monte Carlo simulations and semiempirical equations describing multiple electron scattering. A well-defined relationship is found between the maximum HAADF STEM intensity and sample thickness which is exploited (a) to derive a quantitative description for the mean quadratic scattering angle and (b) to calculate the transmitted HAADF STEM intensity as a function of the relevant materials parameters and electron energy. The formalism can be also applied to determine TEM sample thicknesses by minimizing the contrast of the sample as a function of the electron energy.
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Affiliation(s)
- M Pfaff
- Laboratorium für Elektronenmikroskopie and Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), Germany.
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Hochberg N, Sosa M, Trivedi J, Pfaff M, Macleod W, Benoit C, Chen L, Kogelman L, Ooi W, Karchmer A, Wilson M, Hamer D, Barnett E. High-risk travelers in the Boston Area Travel Medicine Network: Demographics, trip plans and vaccinations. Int J Infect Dis 2010. [DOI: 10.1016/j.ijid.2010.02.1550] [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: 11/27/2022] Open
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Guthke R, Zeilinger K, Sickinger S, Schmidt-Heck W, Buentemeyer H, Iding K, Lehmann J, Pfaff M, Pless G, Gerlach JC. Dynamics of amino acid metabolism of primary human liver cells in 3D bioreactors. Bioprocess Biosyst Eng 2006; 28:331-40. [PMID: 16550345 PMCID: PMC1705492 DOI: 10.1007/s00449-005-0040-1] [Citation(s) in RCA: 7] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Accepted: 12/12/2005] [Indexed: 11/29/2022]
Abstract
The kinetics of 18 amino acids, ammonia (NH3) and urea (UREA) in 18 liver cell bioreactor runs were analyzed and simulated by a two-compartment model consisting of a system of 42 differential equations. The model parameters, most of them representing enzymatic activities, were identified and their values discussed with respect to the different liver cell bioreactor performance levels. The nitrogen balance based model was used as a tool to quantify the variability of runs and to describe different kinetic patterns of the amino acid metabolism, in particular with respect to glutamate (GLU) and aspartate (ASP).
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Affiliation(s)
- R Guthke
- Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Beutenbergstr. 11a, 07745, Jena, Germany.
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12
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Lips KS, Volk C, Akinci S, Pfaff M, Schmitt BM, Pfeil U, Arndt P, Miska D, Ermert L, Haberberger RV, Koepsell H, Kummer W. Organische Kationen Transporter setzen Azetylcholin aus dem Atemwegsepithel frei und vermitteln die Epithel-abhängige Bronchokonstriktion. Pneumologie 2005. [DOI: 10.1055/s-2005-862715] [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]
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13
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Pfaff M, Akinci S, Wiegand S, Schütz W, Powaga N, Banno Y, Wess J, Kummer W, Haberberger RV. Die Sphingosinkinase 1 ist in die Signaltransduktionswege muskarinischer M2-Rezeptoren integriert und an der Kontrolle peripherer Atemwege beteiligt. Pneumologie 2005. [DOI: 10.1055/s-2005-862714] [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]
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Pfaff M, Weller K, Woetzel D, Guthke R, Schroeder K, Stein G, Pohlmeier R, Vienken J. Prediction of cardiovascular risk in hemodialysis patients by data mining. Methods Inf Med 2004; 43:106-13. [PMID: 15026849] [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: 04/29/2023]
Abstract
OBJECTIVES The objective of this work was to contribute to the development, validation and application of data mining methods for prediction in decision support systems in medicine. The particular focus was on the prediction of cardiovascular risk factors in hemodialysis patients, specifically the interventricular septum (IVS) thickness of the heart of individual patients as an important quantitative indicator to diagnose left ventricular hypertrophy. The work was based on data from 63 long-term hemodialysis patients of the KfH Dialysis Centre in Jena, Germany. METHODS The approach applied is based on data mining methods and involves four major steps: data based clustering, cluster based rule extraction, rulebase construction and cluster and rule based prediction. The methods employed include crisp and fuzzy algorithms. At each step, logical and medical validation of results was carried out. Different sets of randomly selected patient data were used to train, test and optimize the clusterbases and rulebases for prediction. RESULTS Using the best clusterbase/rulebase combination designed, the IVS thickness cluster ('small' or 'large') was predicted correctly for 30 of the 35 patients with known IVS values in the training data set; no patient was predicted incorrectly and 5 were parity predicted. For the test data set, 4 of the 6 patients with known IVS values were predicted correctly, no patient incorrectly and 2 parity. These results did not substantially differ from those obtained using the second best clusterbase/rulebase combination which was finally recommended for use based on further performance criteria. The prediction of the IVS thickness clusters of the 22 patients with unknown IVS values also yielded good results that were (and could only be) validated by a medical individual risk assessment of these patients. CONCLUSIONS The approach applied proved successful for the cluster and rule based prediction of a quantitative variable, such as IVS thickness, for individual patients from other variables relevant to the problem. The results obtained demonstrate the high potential of the approach and the methods developed and validated to support decision-making in hemodialysis and other fields of medicine by individual risk prediction.
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Affiliation(s)
- M Pfaff
- BioControl Jena GmbH, Wildenbruchstr. 15, 07745 Jena, Germany.
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15
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Abstract
The article examines on the basic of empirical data the discrepancy between the theoretical demand and the practical role of advance directives. Often advance directives have no influence on medical decision-making in clinical care of critically ill patients. The vague language of the widely used standard living wills and the lack of physician-patient communication in the process of delivering an advance directives are contributing factors. However, many physicians even disregard patients' preferences in concrete and meaningful living wills at the end of life. Besides the lack of information many even seriously ill patients do not deliver an advance because they misjudge their medical prognosis and life expectancy. Often the communication between patients and doctors are blocked because they expect from the each other the first step to talk about end of life decisions and advance directives. In this context physicians claim lack of time, training in communication skills and their discomfort in talking about death and dying with their patients.
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Affiliation(s)
- J Vollmann
- Institut für Geschichte und Ethik der Medizin, Friedrich-Alexander-Universität Erlangen-Nuremberg, Erlangen.
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16
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Pfaff M, Vicere A, Otto RM, Wygand J. THE EFFECT OF XENADRINE RFA-1 VS CAFFEINE INGESTION ON RESTING METABOLIC RATE. Med Sci Sports Exerc 2002. [DOI: 10.1097/00005768-200205001-00487] [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: 11/25/2022]
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17
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Abstract
Macrophages and osteoclasts develop unique contact sites with the extracellular matrix called podosomes. Podosomes have been associated with migratory and invasive cell characteristics, but a basic mechanism outlining their function is lacking. We have used chicken and human monocytes differentiating in vitro into osteoclast-like cells in the presence of RANKL-ODF to study these cytoskeletal structures. During the differentiation process, podosomes are redistributed from the cell body in early macrophages to the cell periphery in increasingly spread and multinucleated cells expressing high levels of integrin αVβ3. Immunofluorescence with anti-phosphotyrosine antibodies revealed increased tyrosine-phosphorylation at the basal tips of these podosomes. RANKL-ODF treatment reinforced the peripheral location of podosomes and initiated their partial fusion to larger F-actin-containing structures that displayed reduced levels of tyrosine phosphorylation. Paxillin and the FAK-related kinase Pyk2 colocalized with integrin αVβ3 in the juxtamembrane region surrounding individual podosomes. In lysates of macrophages and differentiated osteoclasts both paxillin and Pyk2 associated with synthetic and recombinant polypeptides containing the C-terminal region of the integrin β3 cytoplasmic domain. These in vitro interactions were direct and they were abolished by substitutions in the β3 integrin peptides known to disrupt integrin function in vivo. The marked adhesion-dependent tyrosine-phosphorylation of Pyk2 and paxillin however did not detectably alter their interaction with β3 tail peptides in cell lysates. Our results provide novel insight into the molecular architecture and the phosphorylation dynamics in podosomes. Moreover, they outline a novel potential mechanism for the recruitment of paxillin and Pyk2 to β3 integrin-dependent cell contacts.
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Affiliation(s)
- M Pfaff
- Ecole Normale Supérieure de Lyon, France.
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18
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19
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Pfaff M. [Drug use: a life choice or health threat]. Gesundheitswesen 2000; 62:S9-12. [PMID: 10838786] [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: 02/16/2023]
Abstract
The term "enjoyment" is used to denote a pleasurable, utility-creating activity or an act of consumption, which, however, may often be accompanied by subsequent risks, health-care costs or reduction in the quality of life. If viewed from the vantage point of health policy, we may quote several examples of consumer behaviour of this type, ranging first and foremost from the consumption of alcohol and nicotine to the use of "hard" drugs. But certain sports activities or sexual behaviour that may prove damaging to other persons must also be mentioned in this context. All these forms of consumption often lead to direct or indirect consequences to health and thereby result in increased health spending amounting to several thousand million DM. The decline in quality of life resulting from the above-mentioned forms of behaviour could be avoided through health promotion and prevention or, at the very least, through measures of rehabilitation, above all, information, counselling, and education, which represent medium- or long-term measures to that effect. Financial incentives or disincentives, for example, via an increase in co-payment in case of illness caused by risky behaviour, have not been as effective as had been expected by many proponents. Product-specific levies, risk-related payments and other financial incentives and disincentives are generally also not as effective as desired. Health policy measures aimed at influencing behaviour via financial measures are particularly ineffective in case of persons addicted to particular types of consumables, especially to drugs: Information, counselling and education represent non-financial forms of influencing and guiding behaviour with a greater scope for success.
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Affiliation(s)
- M Pfaff
- Institut für Volkswirtschaftslehre, Universität Augsburg
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20
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21
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Liu S, Thomas SM, Woodside DG, Rose DM, Kiosses WB, Pfaff M, Ginsberg MH. Binding of paxillin to alpha4 integrins modifies integrin-dependent biological responses. Nature 1999; 402:676-81. [PMID: 10604475 DOI: 10.1038/45264] [Citation(s) in RCA: 269] [Impact Index Per Article: 10.8] [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: 12/17/2022]
Abstract
The alpha4 integrins are indispensable for embryogenesis, haematopoiesis and immune responses, possibly because alpha4 regulates cellular functions differently from other integrins through its cytoplasmic tail. We used novel mimics of the alpha4 tail to identify molecules that could account for alpha4-specific signalling. Here we report that the alpha4 tail, but not several other alpha-subunit tails, binds tightly to the signalling adaptor paxillin. Paxillin physically associated with alpha4 integrins in Jurkat T cells at high stoichiometry, and joining the alpha4 tail to alphaIIb resulted in a complex of integrin alphaIIbbeta3 with paxillin. This association markedly enhanced the rates of alphaIIbbeta3-dependent phosphorylation of focal adhesion kinase and cell migration. It also reduced cell spreading, focal adhesion and stress fibre formation. A point mutation within the alpha4 tail that disrupts paxillin binding reversed all of these effects. Furthermore, alpha4beta1-dependent adhesion to VCAM-1 led to spreading of mouse embryonic fibroblasts derived from paxillin-null but not from wild-type mice. Thus, the tight association of paxillin with the alpha4 tail leads to distinct biochemical and biological responses to integrin-mediated cell adhesion.
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Affiliation(s)
- S Liu
- Department of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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22
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Abstract
We showed previously that the calcium-dependent protease, calpain, cleaves the cytoplasmic domain of the integrin beta3 subunit. To investigate whether susceptibility to calpain is a common feature of all integrin beta subunits, and to map calpain cleavage sites in different integrin beta tails, we treated recombinant cytoplasmic domains of integrin beta1A, beta1D, beta2, beta3 and beta7 subunits with purified calpain in vitro. We found that the cytoplasmic domains of all these integrin chains were cleaved by calpain. HPLC followed by mass spectrometry was used to identify calpain cleavage sites. These sites were clustered in the C-terminal half of the integrin beta cytoplasmic domains in regions flanking the two NXXY motifs, suggesting the possibility that the structural framework provided by these motifs is recognized by calpain. We used the knowledge of these cleavage sites to develop cleavage site-specific antibodies and to demonstrate cleavage of the beta1A cytoplasmic domain in intact platelets stimulated with calcium ionophore or thrombin. Thus susceptibility to calpain cleavage is common to integrin beta subunits, can be induced in intact cells, and appears to favor regions surrounding two conserved NXXY motifs.
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Affiliation(s)
- M Pfaff
- Department of Vascular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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23
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Boissy P, Machuca I, Pfaff M, Ficheux D, Jurdic P. Aggregation of mononucleated precursors triggers cell surface expression of alphavbeta3 integrin, essential to formation of osteoclast-like multinucleated cells. J Cell Sci 1998; 111 ( Pt 17):2563-74. [PMID: 9701555 DOI: 10.1242/jcs.111.17.2563] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [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] Open
Abstract
Alphavbeta3 is a key integrin mediating adhesion of multinucleated osteoclasts during bone resorption. 1, 25-dihydroxyvitamin D3 upregulates alphavbeta3 integrin expression in mononucleated osteoclast precursors and concomitantly stimulates their differentiation into osteoclasts. This suggests that this integrin could play a major role during osteoclast differentiation.We have developed an in vitro model, in which 1, 25-dihydroxyvitamin D3 sequentially modifies the behavior of macrophages: It first induces rounding up of these cells, then their subsequent aggregation and spreading, which finally leads to cell fusion and the formation of osteoclast-like multinucleated giant cells. We show that, while 1,25-dihydroxyvitamin D3 stimulates the de novo synthesis of alphavbeta3 in macrophages early in this process, its accumulation on the surface is triggered by cell aggregation. A high level of integrin alphavbeta3 cell surface expression correlates with macrophage spreading preceding fusion. This was confirmed by means of novel cell permeable peptides containing the C-terminal sequence of the integrin beta3 tail to specifically block (alphavbeta3 function. Although this peptide has no effect on the aggregation step, it disrupts the spreading of osteoclast precursors and consequently inhibits their fusion. These findings suggest a novel role of the integrin alphavbeta3 in a discrete step of osteoclast differentiation.
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Affiliation(s)
- P Boissy
- Laboratoire de Biologie Moléculaire et Cellulaire de l'Ecole Normale Supérieure de Lyon, UMR49 CNRS/ENS, INRA 913, allée d'Italie, France
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24
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Abstract
Integrin cell-adhesion receptors mediate interactions between cells and the extracellular matrix. Dynamic regulation of integrin adhesive function is termed 'activation' or 'inside-out' signalling. Activation is key to integrin function in processes as diverse as cell migration, the organization of the extracellular matrix and platelet aggregation. Consequently, there has been an intense effort to elucidate the molecular mechanism of integrin activation. This has resulted in the recent identification of novel cytoplasmic partners for integrins and the emerging characterization of the signal-transduction pathways that regulate integrin 'inside-out' signalling. Here, the authors review the recent developments that have provided us with an increased understanding of the basis of integrin activation.
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Affiliation(s)
- P E Hughes
- Dept of Vascular Biology, Scripps Research Institute, La Jolla, CA 92037, USA.
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25
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26
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Abstract
The purpose of this study was to describe a method to quantify dynamic patellar tracking using kinematic MRI (KMRI). Twelve normal females and three patients with patellofemoral pain participated. Imaging was performed with a 1.5-T/64-MHz MR system using a fast spoiled gradient-recalled acquisition in the steady state (GRASS) pulse sequence. A nonferromagnetic positioning device permitted active, bilateral knee extension against resistance (15% bwt) from 45 degrees knee flexion to full extension. Subjects were instructed to extend their knees at a rate of 9 degrees per second, which allowed images to be obtained at 45 degrees, 36 degrees, 27 degrees, 18 degrees, 9 degrees, and 0 degrees. All images were assessed for medial/lateral patellar displacement, patellar tilt, and sulcus angle using a computer-aided system. Normal patellar motion was characterized by medial movement from 45 degrees to 18 degrees, followed by a reversal toward lateral displacement from 18 degrees to full extension. The results for patellar tilt revealed a tendency toward decreasing lateral tilt as the knee extended. Sulcus angle measurements indicated that the patella was moving to a more shallow portion of the trochlear groove (superiorly) during extension.
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Affiliation(s)
- C M Powers
- Department of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles 90033, USA
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27
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Abstract
Integrin cytoplasmic domains connect these receptors to the cytoskeleton. Furthermore, integrin-cytoskeletal interactions involve ligand binding (occupancy) to the integrin extracellular domain and clustering of the integrin. To construct mimics of the cytoplasmic face of an occupied and clustered integrin, we fused the cytoplasmic domains of integrin beta subunits to an N-terminal sequence containing four heptad repeat sequences. The heptad repeats form coiled coil dimers in which the cytoplasmic domains are parallel dimerized and held in an appropriate vertical stagger. In these mimics we found 1) that both conformation and protein binding properties are altered by insertion of Gly spacers C-terminal to the heptad repeat sequences; 2) that the cytoskeletal proteins talin and filamin are among the polypeptides that bind to the integrin beta1A tail. Filamin, but not talin binding, is enhanced by the insertion of Gly spacers; 3) binding of both cytoskeletal proteins to beta1A is direct and specific, since it occurs with purified talin and filamin and is inhibited in a point mutant (beta1A(Y788A)) or in splice variants (beta1B, beta1C) known to disrupt cytoskeletal associations of beta1 integrins; 4) that the muscle-specific splice variant, beta1D, binds talin more tightly than beta1A and is therefore predicted to form more stable cytoskeletal associations; and 5) that the beta7 cytoplasmic domain binds filamin better than beta1A. The structural specificity of these associations suggests that these mimics offer a useful approach for the analysis of the interactions and structure of the integrin cytoplasmic face.
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Affiliation(s)
- M Pfaff
- Department of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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28
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Baker EK, Tozer EC, Pfaff M, Shattil SJ, Loftus JC, Ginsberg MH. A genetic analysis of integrin function: Glanzmann thrombasthenia in vitro. Proc Natl Acad Sci U S A 1997; 94:1973-8. [PMID: 9050889 PMCID: PMC20027 DOI: 10.1073/pnas.94.5.1973] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [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: 02/03/2023] Open
Abstract
Glanzmann thrombasthenia, an inherited bleeding disorder, can be caused by a defect or deficiency in platelet integrin alphaIIb beta3 (GPIIb-IIIa). Studies of thrombasthenia variants have facilitated identification of sites involved in the functions of alphaIIb beta3 and other integrins. Such sites include those that bind ligand and those that participate in the "activation" of alphaIIb beta3 required for high affinity binding of ligands such as fibrinogen or PAC1, a monoclonal antibody. Here we describe the isolation of such variants, created in vitro with Chinese hamster ovary cells that express an activated form of alphaIIb beta3. These cells were exposed to a mutagen, ethyl methane sulfonate, and variants that lost the capacity to bind PAC1 were isolated by fluorescence-activated cell sorting. These variants were grouped into three phenotypic classes. One comprised integrin mutations that disrupt ligand binding function; a second comprised mutations that interfere with the capacity of cells to activate the integrin. Most of these activation-defective mutations were in the integrin cytoplasmic domain, but surprisingly, several were caused by mutations affecting three closely spaced residues in the beta3 extracellular domain. A third class of mutants exhibited a defect in integrin activation not ascribable to changes in the integrin sequence. Thus, these may represent mutated signaling molecules required for integrin activation. This unbiased genetic approach provides new insights into the structural basis of integrin function and may assist in identifying the cellular events that regulate integrin function.
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Affiliation(s)
- E K Baker
- Department of Vascular Biology, Scripps Research Institute, La Jolla, CA 92037, USA
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29
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Hughes PE, Renshaw MW, Pfaff M, Forsyth J, Keivens VM, Schwartz MA, Ginsberg MH. Suppression of integrin activation: a novel function of a Ras/Raf-initiated MAP kinase pathway. Cell 1997; 88:521-30. [PMID: 9038343 DOI: 10.1016/s0092-8674(00)81892-9] [Citation(s) in RCA: 404] [Impact Index Per Article: 15.0] [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: 02/03/2023]
Abstract
Rapid modulation of ligand binding affinity ("activation") is a central property of the integrin cell adhesion receptors. Using a screen for suppressors of integrin activation, we identified the small GTP-binding protein, H-Ras, and its effector kinase, Raf-1, as negative regulators of integrin activation. H-Ras inhibited the activation of integrins with three distinct alpha and beta subunit cytoplasmic domains. Suppression was not associated with integrin phosphorylation and was independent of both mRNA transcription and protein synthesis. Furthermore, suppression correlated with activation of the ERK MAP kinase pathway. Thus, regulation of integrin affinity state is a novel, transcription-independent function of a Ras-linked MAP kinase pathway that may mediate a negative feedback loop in integrin function.
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Affiliation(s)
- P E Hughes
- Department of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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30
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Abstract
Fibrillin-1 is a major constituent of tissue microfibrils that occur in most connective tissues, either in close association with or independent of elastin. To test possible cell-adhesive functions of this protein, we used recombinant human fibrillin-1 polypeptides produced in a mammalian expression system in cell attachment and solid-phase integrin binding assays. Fibrillin-1 polypeptides containing the single RGD sequence located in the fourth 8-cysteine domain, mediated distinct cell adhesion of a variety of cell lines and bound to purified integrin alphaVbeta3. Integrins alphaIIbbeta3, alpha5beta1, alpha2beta1 and alpha1beta1 did not interact with any of the recombinant fibrillin-1 peptides. Our results indicate a novel role for fibrillin-1 in cellular interactions mediated via an RGD motif that is appropriately exposed for recognition by integrin alphaVbeta3.
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Affiliation(s)
- M Pfaff
- Max Planck Institut für Biochemie, Martinsried, Germany
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31
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Abstract
The mouse cell line GD25, which lacks expression of the beta 1 family of integrin heterodimers due to disruption of the beta 1 integrin subunit gene, was used for expression of full-length cDNA coding for splice variant A of the mouse beta 1 integrin subunit. In a stably transformed clone (GD25-beta 1A), the expressed protein was found to form functional heterodimeric receptors together with the subunits alpha 3, alpha 5, and alpha 6. Both GD25 and GD25-beta 1A attached to fibronectin and formed focal contacts which contained alpha v beta 3, but no detectable alpha 5 beta 1A. The presence of GRGDS peptide allowed alpha 5 beta 1A to locate to focal contacts of GD25-beta 1A cultured on fibronectin, while the beta 1-null GD25 cells were unable to attach under these conditions. Affinity chromatography revealed that alpha 5 beta 1A and alpha v beta 3 could bind to a large cell-binding fragment of fibronectin. alpha 5 beta 1A strongly promoted polymerization of fibronectin into a fibrillar network on top of the cells. Whereas little alpha v beta 3 was colocalized with the fibronectin fibrils in GD25-beta 1A cells, this integrin was able to support fibronectin fibril polymerization in GD25 cells. However, the alpha v beta 3-induced polymerization was less efficient and occurred mainly in dense cultures of the GD25 cells. Thus, while both alpha 5 beta 1A and alpha v beta 3 are able to support adhesion to fibronectin, alpha v beta 3 dominates in the formation of focal contacts, and alpha 5 beta 1A has a prime function in fibronectin matrix assembly. This is the first report on fibronectin matrix assembly in the absence of beta 1 integrins.
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Affiliation(s)
- K Wennerberg
- Department of Medical and Physiological Chemistry, Biomedical Center, Uppsala, Sweden
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32
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Pfaff M, Sasaki T, Tangemann K, Chu ML, Timpl R. Integrin-binding and cell-adhesion studies of fibulins reveal a particular affinity for alpha IIb beta 3. Exp Cell Res 1995; 219:87-92. [PMID: 7543056 DOI: 10.1006/excr.1995.1208] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [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: 01/25/2023]
Abstract
The extracellular matrix proteins fibulin-1 (variants C and D) and fibulin-2 occur in basement membranes and in vessel walls and are thus potential candidates for cellular interactions. Recombinant forms of these proteins were obtained from stably transfected kidney cell clones and examined for cell-adhesion activity and binding to five different purified integrins. The two variants of mouse fibulin-1 were inactive in all these assays. Mouse fibulin-2, however, bound to alpha IIb beta 3 integrin almost as strongly as fibrinogen, while a lower activity was found for alpha V beta 3 and almost none for alpha 5 beta 1 integrin. Synthetic SVPRGDLDG peptide, corresponding to the single RGD site of mouse fibulin-2, was a strong antagonist of alpha IIb beta 3 integrin binding. Its affinity for alpha V beta 3 and alpha 5 beta 1 integrins was, however, 10- to 50-fold lower compared to GRGDS. Mouse fibulin-2 also promoted adhesion of thrombin-stimulated platelets and of some established cell lines which could be inhibited by RGD peptides. Human fibulin-2, in which the RGD sequence is changed to RSS, bound less strongly to alpha IIb beta 3 integrin and showed no cell-adhesion activity. Together these data suggest a potential role in hemostatic control for mouse fibulin-2 and possibly also for human fibulin-2.
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Affiliation(s)
- M Pfaff
- Max-Planck-Institut für Biochemie, Martinsried, Germany
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Fässler R, Pfaff M, Murphy J, Noegel AA, Johansson S, Timpl R, Albrecht R. Lack of beta 1 integrin gene in embryonic stem cells affects morphology, adhesion, and migration but not integration into the inner cell mass of blastocysts. J Biophys Biochem Cytol 1995; 128:979-88. [PMID: 7533171 PMCID: PMC2120384 DOI: 10.1083/jcb.128.5.979] [Citation(s) in RCA: 210] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A gene trap-type targeting vector was designed to inactivate the beta 1 integrin gene in embryonic stem (ES) cells. Using this vector more than 50% of the ES cell clones acquired a disruption in the beta 1 integrin gene and a single clone was mutated in both alleles. The homozygous mutant did not produce beta 1 integrin mRNA or protein, while alpha 3, alpha 5, and alpha 6 integrin subunits were transcribed but not detectable on the cell surface. Heterozygous mutants showed reduced beta 1 expression and surface localization of alpha/beta 1 heterodimers. The alpha V subunit expression was not impaired on any of the mutants. Homozygous ES cell mutants lacked adhesiveness for laminin and fibronectin but not for vitronectin and showed a reduced association with a fibroblast feeder layer. Furthermore, they did not migrate towards chemoattractants in fibroblast medium. None of these functions were impaired in heterozygous mutants. Scanning electron microscopy revealed that homozygous cells showed fewer cell-cell junctions and had many microvilli not usually found on wild type and heterozygous cells. This profound change in cell shape is not associated with gross alterations in the expression and distribution of cytoskeletal components. Unexpectedly, microinjection into blastocysts demonstrated full integration of homozygous and heterozygous mutants into the inner cell mass. This will allow studies of the consequences of beta 1 integrin deficiency in several in vivo situations.
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Affiliation(s)
- R Fässler
- Max-Planck-Institute for Biochemistry, Martinsried, Germany
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34
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Pfaff M, McLane MA, Beviglia L, Niewiarowski S, Timpl R. Comparison of disintegrins with limited variation in the RGD loop in their binding to purified integrins alpha IIb beta 3, alpha V beta 3 and alpha 5 beta 1 and in cell adhesion inhibition. Cell Adhes Commun 1994; 2:491-501. [PMID: 7538018 DOI: 10.3109/15419069409014213] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The inhibitory capacities of six different disintegrins and one related neurotoxin analogue for the binding of RGD-dependent integrins to either fibrinogen, vitronectin or fibronectin were compared in solid phase assays. Echistatin and flavoridin were the most active inhibitors for alpha V beta 3 and alpha 5 beta 1 integrins and moderately exceeded the activity of the natural protein ligands. The same disintegrins together with eristostatin, bitistatin and barbourin were also very potent inhibitors of fibrinogen binding to alpha IIb beta 3 integrin. For all three integrins, albolabrin showed the lowest affinity, but it still clearly exceeded that of synthetic GRGDS. However, assay conditions may determine these relative affinities, as shown for the alpha IIb beta 3 and alpha V beta 3 integrins when used either in immobilized or soluble form. For alpha IIb beta 3, however, a close correlation was found between KD values determined in platelet binding assays and the concentrations required for half maximal inhibition of three disintegrins. The inhibiting capacity of disintegrins in assays with purified integrins also correlated reasonably well with their inhibition of cell attachment to RGD-dependent protein substrates. However, sequence differences in the RGD loops of the various disintegrins may not fully account for the 20-100-fold difference in their binding capacities. This was particularly evident for echistatin and albolabrin, which differ in this region only by two conservative substitutions but have considerably different inhibitory activities. More remote regions of the disintegrins and alignment of disulfide bridges are therefore likely to contribute to their affinity and selectivity.
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Affiliation(s)
- M Pfaff
- Max-Planck-Institut für Biochemie, Martinsried, Germany
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35
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Kübler N, Reuther J, Kirchner T, Pfaff M, Müller-Hermelink HK, Albert R, Sebald W. IgG monoclonal antibodies that inhibit osteoinductivity of human bone matrix-derived proteins (hBMP/NCP). Int J Oral Maxillofac Surg 1994; 23:420-2. [PMID: 7890988 DOI: 10.1016/s0901-5027(05)80035-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [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: 01/27/2023]
Abstract
Monoclonal hBMP/NCP (human bone morphogenetic protein and associated noncollagenous proteins) antibodies of the IgG class were produced. In vitro, 12 of 19 hBMP/NCP antibodies showed functional inhibition of hBMP/NCP-induced chondroneogenesis in a neonatal muscle tissue assay. Inducing factors were characterized by their inhibiting antibodies with immunoblotting. Several peptide factors seem to be involved in the cascade of induced chondro- and osteogenesis.
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Affiliation(s)
- N Kübler
- Department of Oral and Maxillofacial Surgery, University of Würzburg, Germany
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36
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Pfaff M, Göhring W, Brown JC, Timpl R. Binding of purified collagen receptors (alpha 1 beta 1, alpha 2 beta 1) and RGD-dependent integrins to laminins and laminin fragments. Eur J Biochem 1994; 225:975-84. [PMID: 7525287 DOI: 10.1111/j.1432-1033.1994.0975b.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Integrins alpha 1 beta 1 and alpha 2 beta 1 when purified by collagen affinity chromatography, showed distinct binding to mouse tumor laminin-1, which has the chain composition alpha 1 beta 1 gamma 1. The binding was, however, about 10-fold lower than to collagen IV. Only little (alpha 1 beta 1) or no binding (alpha 2 beta 1) was observed to two different laminin isoforms (alpha 2 beta 1 gamma 1, alpha 2 beta 2 gamma 1) from human placenta. Binding to laminin-1 was abolished by EDTA and could be specifically inhibited by antibodies to the respective integrin alpha subunit. These antibodies also inhibited cell adhesion to collagens. The binding of soluble integrins was weaker than that of immobilized integrins but could be enhanced by an activating anti(beta 1 integrin). No enhancement was observed for immobilized integrins. Studies with laminin-1 fragments demonstrated lack of binding to the major cell-adhesive fragment E8 from the long arm, fragments E3 and E4, involved in heparin-binding and self-assembly, respectively, and fragment P1, corresponding to the inner segments of the short arms. A larger short-arm fragment (E1XNd), which lacks the N-terminal beta 1 chain domains V and VI, was as active as laminin. Together, these results, suggested the localization of the binding sites for alpha 1 beta 1 and alpha 2 beta 1 to the N-terminal region of the laminin alpha 1 chain. Fragment P1 but not intact laminin-1 bound to alpha V beta 3 integrin in an EDTA-sensitive and RGD-sensitive manner, underscoring previous data on the cryptic nature of the RGD site in laminin-1. Further analyses by surface plasmon resonance assays demonstrated a KD = 50 nM for alpha 2 beta 1/laminin-1 binding and a KD = 450 nM for alpha V beta 3/fragment P1 binding and confirmed the anti-beta 1-mediated increase in affinity for alpha 2 beta 1.
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Affiliation(s)
- M Pfaff
- Max-Planck-Institut für Biochemie, Martinsried, Germany
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Pfaff M. German reform a model for U.S. A reply to Thomas Weil. Health Prog 1994; 75:30-1. [PMID: 10136076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Affiliation(s)
- M Pfaff
- University of Augsburg, Federal Republic of Germany
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Pfaff M, Tangemann K, Müller B, Gurrath M, Müller G, Kessler H, Timpl R, Engel J. Selective recognition of cyclic RGD peptides of NMR defined conformation by alpha IIb beta 3, alpha V beta 3, and alpha 5 beta 1 integrins. J Biol Chem 1994; 269:20233-8. [PMID: 8051114] [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: 01/28/2023] Open
Abstract
The binding of purified fibrinogen receptor alpha IIb beta 3, vitronectin receptor alpha V beta 3, and fibronectin receptor alpha 5 beta 1 to their corresponding ligands in solid-phase binding assays was used to examine the inhibitory activity of various linear and cyclic penta- and hexapeptides of different conformation containing RGD or RAD sequences. Cyclic peptides with different defined backbone conformations were designed by introducing a single D-amino acid or a proline at different positions in the ring. The data were calibrated for alpha IIb beta 3 integrin incorporated into a planar lipid bilayer by a physical method (total internal reflection fluorescence microscopy) which yielded KD = 1.7 microM for a linear RGD peptide and KD = 0.03 microM for fibrinogen. With this integrin, three cyclic hexapeptides ([GRGDFL], [ARGDFV], [GRGDFV]) were 2-4-fold more inhibitory than the linear GRGDS peptide in solid-phase assays and showed similar inhibition as the fibrinogen ligand. Six peptides had the same or a 2-fold lower activity as the linear reference peptide, and three peptides were up to 7-fold less active. Replacement of Arg or Asp by their stereoisomers or Gly by Ala resulted in a 100-1000-fold reduction in activity. With the two other integrins, a single cyclic pentapeptide [RGDFV] was 10-fold more active (alpha V beta 3) or equal in activity (alpha 5 beta 1) to linear GRGDS, while all of the other cyclic peptides were moderately or distinctly less active. Changes in the RGD sequence caused a less dramatic reduction in binding strength for alpha V beta 3 and alpha 5 beta 1 than for alpha II beta 3. Inhibitory activity was compared with the distance between the C beta atoms of Arg and Asp residues as determined by NMR and indicated that the optimum distance is in the range of 0.75-0.85 nm for alpha IIb beta 3 and at or below 0.67 nm for alpha V beta 3 and alpha 5 beta 1. This indicates that alpha IIb beta 3 less sensitive to variations in the RGD backbone structure and can accommodate a larger distance than the integrins alpha V beta 3 and alpha 5 beta 1.
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Affiliation(s)
- M Pfaff
- Max-Planck-Institut für Biochemie, Martinsried, Federal Republic of Germany
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39
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Pfaff M, Tangemann K, Müller B, Gurrath M, Müller G, Kessler H, Timpl R, Engel J. Selective recognition of cyclic RGD peptides of NMR defined conformation by alpha IIb beta 3, alpha V beta 3, and alpha 5 beta 1 integrins. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)31981-6] [Citation(s) in RCA: 417] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Pfaff M, Nagel F. [Comparison of public health systems within the European Community]. Gesundheitswesen 1994; 56:86-91. [PMID: 8148597] [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: 01/29/2023]
Abstract
Only two out of three ideal types of health care systems can be observed in the European Community (EC): Centrally planned systems (countries with a national health service) and systems managed mainly by associations of health insurance funds and also of providers (countries with a social insurance system). We find no country with a market-type health care system in Europe. Both types of systems occurring in the EC are compared with each other, both with regard to their ideal types and also to their actual operations when judged on grounds of financing and production of health care. When seen as ideal types, we note considerable differences. Real types however exhibit only gradual differences. The shares of major subcategories of health spending differ widely between EC countries. These differences, however, cannot be attributed to the different health care systems. Similar observations can be made regarding different forms of payment for hospital care and for physician services and also regarding the share of total health expenditure in GDP.
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Affiliation(s)
- M Pfaff
- Internationales Institut für empirische Sozialökonomie, Universität Augsburg
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41
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Alden K, Dellinger J, Glasgow A, McCulley-Hall S, Huang F, Leatherwood L, Parce N, Pfaff M, Queen D, Richard N. NURSETALK: the latest addition to the information highway. Proc Annu Symp Comput Appl Med Care 1994:1018. [PMID: 7949857 PMCID: PMC2247943] [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] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
NURSETALK is an electronic bulletin board system (BBS) developed to provide information and meet the communication needs of three different nursing organizations in North Carolina. It was designed and conceptualized from a user perspective to promote functionality and acceptance.
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Vollmers HP, Stulle K, Dämmrich J, Pfaff M, Papadopoulos T, Betz C, Saal K, Müller-Hermelink HK. Characterization of four new gastric cancer cell lines. Virchows Arch B Cell Pathol Incl Mol Pathol 1993; 63:335-43. [PMID: 8100658 DOI: 10.1007/bf02899281] [Citation(s) in RCA: 24] [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: 01/28/2023]
Abstract
Four well differentiated gastric adenocarcinoma cell lines from German patients have been established from primary tumors (St 23132, St 3051) and lymph node metastases (St 2474, St 2957). The tumor cells were isolated by enzymatic or mechanical treatment. All four lines grew as solid tumors in nude mice and formed colonies in soft agar. The doubling time of the cells in culture was 25-32 h. Further characteristics of the lines were a considerable chromosomal aneuploidy, (the chromosomal numbers varying from 30-109 with many numerical and structural abnormalities), a stable keratin expression (Ck 8, 18, 19), the expression and secretion of CEA and CA-19-9 and the overexpression of c-myc. The four stomach cancer cell lines described here are not only a useful addition to the small number of existing lines, but also represent ideal tools for studying tumorigenicity of human stomach cancers in vitro and in vivo.
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Pfaff M, Aumailley M, Specks U, Knolle J, Zerwes HG, Timpl R. Integrin and Arg-Gly-Asp dependence of cell adhesion to the native and unfolded triple helix of collagen type VI. Exp Cell Res 1993; 206:167-76. [PMID: 8387021 DOI: 10.1006/excr.1993.1134] [Citation(s) in RCA: 155] [Impact Index Per Article: 5.0] [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: 01/30/2023]
Abstract
Pepsin-solubilized collagen VI in triple-helical and heat-denatured, unfolded form was shown to promote Mg(2+)- and Mn(2+)-dependent attachment and spreading of various cell lines. On the triple-helical substrate no inhibition of cell adhesion was observed with several synthetic RGD peptides except in the case of A375 melanoma cells. In contrast, adhesion to the unfolded substrate was highly sensitive to RGD inhibition. Nine synthetic peptides were designed according to 10 RGD sequences present in the triple-helical sequence of human collagen alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains. Only one peptide, corresponding to the C-terminal end of alpha 3(VI) chain, showed substantial inhibitory activity, whereas several peptides were active in direct adhesion assays when used as albumin conjugates. Inhibition tests with antibodies to integrin subunits, affinity chromatography, and ligand binding with purified integrins (alpha 1 beta 1, alpha 2 beta 1, alpha V beta 3, and alpha IIb beta 3) were used to identify collagen VI receptors. Binding to the triple-helical substrate is mediated by alpha 1 beta 1 and alpha 2 beta 1 integrins. Binding of both integrins to collagen VI was weaker than that to collagens I and/or IV. Recognition of the denatured substrate is mediated by beta 1 and beta 3 integrins. Activity was shown for alpha 5 beta 1 and alpha V beta 3 and weakly for alpha IIb beta 3 but not all alpha subunits possibly involved were identified. Distinct sets of receptors were also involved in A375 cell binding to triple-helical (beta 1-mediated) and denatured (beta 3-mediated) collagen VI, even though in this case both interactions could be efficiently inhibited by RGD peptides.
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Affiliation(s)
- M Pfaff
- Max-Planck-Institut für Biochemie, Frankfurt-Hoechst, Germany
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Faller G, Vollmers HP, Weiglein I, Marx A, Zink C, Pfaff M, Müller-Hermelink HK. HAB-1, a new heteromyeloma for continuous production of human monoclonal antibodies. Br J Cancer 1990; 62:595-8. [PMID: 2223577 PMCID: PMC1971492 DOI: 10.1038/bjc.1990.336] [Citation(s) in RCA: 15] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
To obtain suitable cell lines for the immortalisation of human lymphocytes, we constructed a heteromyeloma between the murine myeloma Ag8 and human lymphocytes from a highly malignant polymorphic, centroblastic B-cell lymphoma. The thioguanine-resistant and HAT-sensitive heteromyeloma HAB-1 neither secretes nor contains cytoplasmatic immunoglobulins, the cells being EBV negative but positively stained for HLA-BC and the human proliferation marker Ki-67. The karyotype consists of about 50 murine and 20 human chromosomes. The HAB-1 cells grow in suspension and have a doubling rate of about 25-30 h. In fusion experiments with spleen cells from stomach carcinoma patients HAB-1 cells show a 5-7 times higher fusion efficiency than murine Ag8 cells or another heteromyeloma SPM4-0 and give stable antibody producing products. The cell line will be made available to interested scientists.
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Affiliation(s)
- G Faller
- Institut für Pathologie, Universität Würzburg, FR Germany
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Pfaff M, O'Connor R, Vollmers HP, Müller-Hermelink HK. Human monoclonal antibody against a tissue polypeptide antigen-related protein from a patient with a signet-ring cell carcinoma of the stomach. Cancer Res 1990; 50:5192-8. [PMID: 1696168] [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: 12/28/2022]
Abstract
For a comparative study of the humoral immunity of patients with gastric signet-ring cell carcinoma, lymphocytes from spleen and lymph nodes were fused with the heteromyeloma SPM4-0. Immunoglobulin-producing clones were primarily tested in binding assays on autologous and allogeneic tumor cells and tissues. One of the resulting human monoclonal antibodies, designated 56/16 (IgM, lambda), was found to be suitable for a detailed biochemical characterization. Immunoblotting and comparative two-dimensional gel electrophoresis on cell and tissue extracts as well as on preparations of the cytoskeleton revealed that the main epitope is not an integral membrane molecule but a degradation product of cytokeratin 8, which is a main component of the tumor marker, tissue polypeptide antigen. The Mr 38,000/45,000 antigen could be identified in tumor and normal tissues, with highest expression in secretory cells and organs. Thus, the human monoclonal antibody 56/16 might represent an immune response in the patient against breakdown products of cytokeratin 8, which are released from the tumor cells during cell division, secretion, or cell death. A possible association of the antibody with the secretory activity of signet-ring carcinoma cells is discussed.
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Affiliation(s)
- M Pfaff
- Pathology Institute, University of Wurzburg, Federal Republic of Germany
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Peak MJ, Pfaff M, Peraino C. Chlorpromazine reduces UV-induced squamous cell carcinogenesis in hairless mice and enhances UV-induced DNA damage in cultured cells. Br J Cancer 1989; 60:220-2. [PMID: 2765369 PMCID: PMC2247052 DOI: 10.1038/bjc.1989.255] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Administration of the photoactivable compound chlorpromazine (CPZ) to SKH-1 hairless mice via their drinking water (CPZ, 0.01%) significantly reduced the rates of accumulation and yields of squamous cell carcinomas induced by long-term repeated exposures of these animals to solar UV radiation. This protective effect of CPZ was partially reversed in mice given a single injection of ethyl nitrosourea at birth. In in vitro studies, the presence of CPZ (0.2 mM) in mammalian cell cultures enhanced the yield of DNA single-strand breaks induced in the cells by exposure to monochromatic UVA radiation at 334 nm. Collectively, the results suggest that CPZ may exert antineoplastic effects against UV-induced skin tumours by the induction of DNA damage.
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Affiliation(s)
- M J Peak
- Biological, Environmental, and Medical Research Division, Argonne National Laboratory, IL 60439-4833
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Abstract
In STU mice bearing metastasizing SV40-transformed 51A-232B-M tumors, an immune response against a cellular 60kDa protein (p60) developed in about 50% of the tumor-bearing animals, in addition to the response against SV40 large T-antigen and cellular protein p53. The anti-p60 auto-immune response could be observed as early as 11 days after tumor challenge and was strictly linked with metastatic spread but was not a prerequisite for metastasis. Anti-p60 antibodies could not be detected in sera of animals bearing metastasizing Rous-sarcoma virus-transformed or methylcholanthrene-induced tumors, or in sera from human cancer patients with clinically confirmed metastatic spread. The anti-p60 auto-antibodies showed a broad cross-reactivity against components of similar size in a great number of cell lines of various species and in normal mouse tissue. The p60 auto-antigen is a cytoplasmic protein which is neither phosphorylated nor glycosylated in vivo. Immunoblotting performed with fresh cell lysates under non-reducing conditions using tumor-bearer sera revealed a diffuse p60 double band, but under reducing conditions only one sharp p60 band was observed. The reaction of p60 with anti-p60 auto-antibodies could be completely blocked by pre-treatment of fresh cell lysates with N-ethylmaleimide or p-chloromercuriphenyl sulfonate, or by oxidation in air prior to immunoblotting, indicating that the anti-p60 autoimmune response was directed against an epitope sensitive to SH-group-blocking reagents. Immunofluorescence studies with tumor-bearer sera showed only a very weak cytoplasmic fluorescence, possibly due to the nature of the p60 SH-groups in situ being masked. Immunoprecipitates with monoclonal antibodies against SV40 large T-antigen and p53 obtained from fresh cell lysates of SV40-transformed tumor cells contained no associated p60 auto-antigen. The p60 auto-antigen was purified from tumor cell homogenates with an enrichment factor of about 2,000; its iso-electric point is at pH 6.8. Determination of the biological half-life of p60 yielded a value of about 28 hr. The p60 auto-antibodies in pools of tumor-bearer sera taken at day 40 after tumor challenge all belonged to the IgG1 subclass.
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Affiliation(s)
- H E Manneck
- Friedrich-Miescher-Laboratorium der Max-Planck-Gesellschaft, Tübingen, FRG
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Abstract
A rabbit antiserum against highly purified casein kinase II from mouse tumor cells was used for immunolocalization of the enzyme in fixed, permeabilized mouse cells. Casein kinase II was highly accumulated in nucleoli compared to the extra-nucleolar space of the nucleus or to the cytoplasma. Casein kinase II samples highly purified from the cytoplasma, from the extra-nucleolar fraction of the nucleus or from nucleoli exhibited no differences with respect to structure and function. All samples originally had an alpha 2 beta 2 structure (alpha, 42 kDa; beta, 24 kDa) showing formation of the alpha'-chain (36 kDa) only in the late steps of purification. The isoelectric point of the alpha-chain of all three samples was pH 7.7 and that of the beta-chain was pH 6.4-6.6. Using ATP or GTP, all three casein kinase II samples gave the same results of maximum phosphorylation of purified nucleolar marker phosphoproteins pp105/C23, pp135 and B23, yielding pp135 as one of the most highly phosphorylated proteins with an incorporation of about 75 phosphate groups per molecule pp135. Studies on optimum conditions of phosphorylation of nucleolar phosphoproteins by casein kinase II revealed that each of the protein substrates individually responded to alterations of assay parameters such as pH, magnesium ion and sodium chloride concentrations indicating that predominantly individual structural criteria were responsible for optimum phosphorylation. The determination of the apparent Km of casein kinase II for purified nucleolar phosphoproteins yielded values of 0.15 microM (pp105/C23), 0.1 microM (pp135) and 1.0 microM (B23) identifying them as high-affinity substrates of casein kinase II.
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Affiliation(s)
- M Pfaff
- Friedrich-Miescher-Laboratorium der Max-Planck-Gesellschaft, Tübingen, F.R.G
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Pfaff M, Nagel F. Consequences for hospitals resulting from demographic, social and morbidity changes: a European perspective. Int J Health Plann Manage 1986; 1:311-33. [PMID: 10281782 DOI: 10.1002/hpm.4740010503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The last 40 years has been a time of rapid demographic, social and economic change in most countries of the world. In Europe, the ageing of the population, a decrease in household size, and the reduced importance of parasitic and infectious diseases along with an increase in chronic and degenerative diseases are some of the most notable results of industrialization, urbanization and medical progress. These developments lead to changing demands not only for the services of hospitals but upon the health care system at large. Most recently, and in addition, these changes have had to be faced under resource constraints resulting from decreased economic growth. This article focuses on the similarities and differences within and across the health care systems of European countries, and on their efforts to respond to the changes which have taken place and are likely to continue in the near future. In so doing, it relates the various demographic, social and economic changes taking place in these countries to the structural changes noticeable in the hospital sector. The results obtained by statistical analyses of empirical evidence lead us to conclude that demographic and social variables may better explain the differences in hospital use within a given country over longer stretches of time than across countries at a given point in time. In the latter case, economic variables--differences in gross domestic product (GDP) per capita--serve as major explanations of the cross-country differences found. Changes in demographic, social and morbidity factors are also mirrored in the relative importance of hospital departments, at a given point in time and also in changes over time. Major changes have taken place within the health care systems. Hospitals are losing ground to other forms of health care: for instance, to institutions providing pre-hospital and post-hospital treatment. The need for more caring patterns of service, rather than for more curing, accounts for yet another overall trend. Hospitals have started to respond to this need by offering more 'semi-stationary' and part-time health care facilities. These developments go hand in hand with the establishment of closer relations between hospitals and other facilities within the health care system, and with improved non-stationary health care services.
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Abstract
Subjective interpretation of angiographic left ventricular regional wall motion is routinely performed with knowledge of the location and extent of coronary artery stenosis. We studied 100 patients with coronary artery disease in order to determine the accuracy of such wall motion assessment relative to a more objective standard based upon computer-assisted left ventricular (LV) ejection fraction and end-systolic fractional shortening referenced to the end-diastolic area centroid. Only 379 of 700 (54%) region-by-region comparisons of wall motion were in precise agreement. Computer-assisted wall motion analysis correlated significantly better with ejection fraction than did subjective analysis (r = 0.82 vs r = 0.61, p less than 0.002). In 56 patients, in whom major discordance was noted, subjective assessment of wall motion correlated significantly better with the presence of coronary artery stenosis (p less than 0.05), but objective assessment correlated significantly better with ejection fraction in these same patients (p less than 0.02). These data suggest that the accuracy of subjective assessment of regional wall motion, relative to global ejection fraction, can be adversely biased by knowledge of the patient's coronary anatomy. Because of the inherently reproducible nature of the algorithmic process, and in light of the better correlation with global function, computer-assisted analysis of regional wall motion might be preferable to conventional subjective assessment.
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