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Kreissner KO, Faller B, Talucci I, Maric HM. MARTin-an open-source platform for microarray analysis. Front Bioinform 2024; 4:1329062. [PMID: 38405547 PMCID: PMC10885354 DOI: 10.3389/fbinf.2024.1329062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/15/2024] [Indexed: 02/27/2024] Open
Abstract
Background: Microarray technology has brought significant advancements to high-throughput analysis, particularly in the comprehensive study of biomolecular interactions involving proteins, peptides, and antibodies, as well as in the fields of gene expression and genotyping. With the ever-increasing volume and intricacy of microarray data, an accurate, reliable and reproducible analysis is essential. Furthermore, there is a high level of variation in the format of microarrays. This not only holds true between different sample types but is also due to differences in the hardware used during the production of the arrays, as well as the personal preferences of the individual users. Therefore, there is a need for transparent, broadly applicable and user-friendly image quantification techniques to extract meaningful information from these complex datasets, while also addressing the challenges posed by specific microarray and imager formats, which can flaw analysis and interpretation. Results: Here we introduce MicroArray Rastering Tool (MARTin), as a versatile tool developed primarily for the analysis of protein and peptide microarrays. Our software provides state-of-the-art methodologies, offering researchers a comprehensive tool for microarray image quantification. MARTin is independent of the microarray platform used and supports various configurations including high-density formats and printed arrays with significant x and y offsets. This is made possible by granting the user the ability to freely customize parts of the application to their specific microarray format. Thanks to built-in features like adaptive filtering and autofit, measurements can be done very efficiently and are highly reproducible. Furthermore, our tool integrates metadata management and integrity check features, providing a straightforward quality control method, along with a ready-to-use interface for in-depth data analysis. This not only promotes good scientific practice in the field of microarray analysis but also enhances the ability to explore and examine the generated data. Conclusion: MARTin has been developed to empower its users with a reliable, efficient, and intuitive tool for peptidomic and proteomic array analysis, thereby facilitating data-driven discovery across disciplines. Our software is an open-source project freely available via the GNU Affero General Public License licence on GitHub.
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Affiliation(s)
- Kai O. Kreissner
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | | | - Ivan Talucci
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
- Department of Neurology, University Hospital Würzburg, Würzburg, Bavaria, Germany
| | - Hans M. Maric
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
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Reckamp K, Redman M, Dragnev K, Villaruz L, Faller B, Al Baghdadi T, Hines S, Minichiello K, Gandara D, Kelly K, Herbst R. 1047P Lung-MAP S1800A: Exploratory analysis of prior immunotherapy outcomes on OS with ramucirumab plus pembrolizumab for NSCLC with PD on prior ICI. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.07.1173] [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] Open
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3
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Hall W, Li J, You Y, Gollub M, Grajo J, Rosen M, dePrisco G, Yothers G, Dorth J, Gross H, Peterson R, Faller B, Moxley K, Jacobs S, Stella P, Haddock M, Hong T, George T. Prospective Validation of the Magnetic Resonance Tumor Regression Grade (MR-TRG) and Correlation With Pathologic Endpoints Score in NRG Oncology GI002. Int J Radiat Oncol Biol Phys 2021. [DOI: 10.1016/j.ijrobp.2021.07.109] [Citation(s) in RCA: 2] [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: 11/28/2022]
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Gobeau N, Stringer R, De Buck S, Tuntland T, Faller B. Evaluation of the GastroPlus™ Advanced Compartmental and Transit (ACAT) Model in Early Discovery. Pharm Res 2016; 33:2126-39. [PMID: 27278908 DOI: 10.1007/s11095-016-1951-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 05/23/2016] [Indexed: 12/17/2022]
Abstract
PURPOSE The aim of this study was to evaluate the oral exposure predictions obtained early in drug discovery with a generic GastroPlus Advanced Compartmental And Transit (ACAT) model based on the in vivo intravenous blood concentration-time profile, in silico properties (lipophilicity, pKa) and in vitro high-throughput absorption-distribution-metabolism-excretion (ADME) data (as determined by PAMPA, solubility, liver microsomal stability assays). METHODS The model was applied to a total of 623 discovery molecules and their oral exposure was predicted in rats and/or dogs. The predictions of Cmax, AUClast and Tmax were compared against the observations. RESULTS The generic model proved to make predictions of oral Cmax, AUClast and Tmax within 3-fold of the observations for rats in respectively 65%, 68% and 57% of the 537 cases. For dogs, it was respectively 77%, 79% and 85% of the 124 cases. Statistically, the model was most successful at predicting oral exposure of Biopharmaceutical Classification System (BCS) class 1 compounds compared to classes 2 and 3, and was worst at predicting class 4 compounds oral exposure. CONCLUSION The generic GastroPlus ACAT model provided reasonable predictions especially for BCS class 1 compounds. For compounds of other classes, the model may be refined by obtaining more information on solubility and permeability in secondary assays. This increases confidence that such a model can be used in discovery projects to understand the parameters limiting absorption and extrapolate predictions across species. Also, when predictions disagree with the observations, the model can be updated to test hypotheses and understand oral absorption.
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Affiliation(s)
- N Gobeau
- Metabolism and Pharmacokinetics (MAP) Department, Novartis Institutes for Biomedical Research, Basel, Switzerland.
- Medicines for Malaria Venture, Route de Pré-Bois 20, PO Box 1826, 1215, Geneva 15, Switzerland.
| | - R Stringer
- Metabolism and Pharmacokinetics (MAP) Department, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - S De Buck
- Drug Metabolism and Pharmacokinetics (DMPK) Department, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - T Tuntland
- Metabolism and Pharmacokinetics (MAP) Department, Genomics Institute of the Novartis Foundation, Novartis Institutes for Biomedical Research, San Diego, California, USA
| | - B Faller
- Metabolism and Pharmacokinetics (MAP) Department, Novartis Institutes for Biomedical Research, Basel, Switzerland
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Slingeneyer A, Faller B, Laroche B, Ehmer B, Mion C. Self-administered daily subcutaneous recombinant human erythropoietin: an open randomised dose-finding study in ESRD patients receiving peritoneal dialysis. Contrib Nephrol 2015; 88:159-68. [PMID: 2040178 DOI: 10.1159/000419526] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- A Slingeneyer
- Service de Néphrologie, Hôpital Lapeyronie, CHU Montpellier, France
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6
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Fliser D, Shilo V, Covic A, Besarab A, Provenzano R, Duliege AM, Chen M, Tong S, Francisco C, Gao HY, Polu K, De Francisco AL, Macdougall I, Macdougall I, Schiller B, Locatelli F, Wiecek A, Francisco C, Tang H, Tong S, Chen M, Duliege AM, Polu K, Mayo M, Covic A, Macdougall I, Macdougall I, Casadevall N, Stead R, Taal M, Faller B, Karras A, Chen M, Tong S, Duliege AM, Rowell R, Polu K, Eckardt KU, Locatelli F, Dusilova Sulkova S, Arnaud S, Bruno P, Arnaud G, Dorina V, Eric A, Gerard M, Cases A, Portoles JM, Calls J, Martinez Castelao A, Sanchez-Guisande D, Segarra A, Tsubakihara Y, Tsubakihara Y, Saito A, Saito A, Saito A, Tsubakihara Y, Martinez-Castelao A, Martinez-Castelao A, Cases A, Fort J, Bonal J, Fulladosa X, Galceran JM, Torregrosa V, Coll E, Minutolo R, Cozzolino M, DI Iorio B, Polito P, Santoro D, Manenti F, Nappi F, Feriozzi S, Conte G, De Nicola L, Mikhail A, Provenzano R, Schiller B, Besarab A, Francisco C, Gao HY, Daley R, Tong S, Mayo M, Yang A, Polu K, Macdougall I, Wiecek A, Schiller B, Canaud B, Locatelli F, Yang A, Chen M, Polu K, Francisco C, Gao HY, Tong S, Duliege AM, Provenzano R, Locatelli F, Locatelli F, Provenzano R, Besarab A, Rath T, Yang A, Mayo M, Francisco C, Macdougall I, Bartnicki P, Baj Z, Majewska E, Rysz J, Fievet P, Assem M, Brazier F, Xu X, Soltani ON, Demontis R, Barsan L, Stancu S, Stancu S, Stanciu A, Capusa C, Petrescu L, Zugravu A, Mircescu G, Malyszko JM, Levin-Iaina N, Malyszko J, Glowinska I, Koc-Zorawska E, Slotki I, Mysliwiec M, Mircescu G, Mircescu G, Capusa C, Stancu S, Barsan L, Grabowski D, Blaga V, Dumitru D, Pchelin I, Shishkin A, Kus T, Usalan C, Tiryaki O, Chin HJ, Chae DW, Kim S, Bertram H, Keller F, Rumjon A, Wood C, Wilson P, Khakoo S, Chai MO, Macdougall IC, Nuria GF, Maria Asuncion F, Jose Maria MG, Carmen C, Paloma Leticia MM, Francisco Javier L, Moniek DG, De Goeij M, Yvette M, Diana G, Friedo D, Nynke H, Lezaic V, Miljkovic B, Petkovic N, Maric I, Vucicevic K, Simic Ogrizovic S, Djukanovic L, Cases A, Martinez-Castelao A, Fort A, Bonal J, Fulladosa X, Galceran JM, Torregrosa V, Coll E, DI Giulio S, DI Giulio S, Galle J, Kiss I, Herlitz H, Wirnsberger G, Claes K, Suranyi M, Guerin A, Winearls C, Addison J, D'souza M, Froissart M, Garrido P, Garrido P, Teixeira M, Costa E, Rodrigues-Santos P, Parada B, Belo L, Alves R, Teixeira F, Santos-Silva A, Reis F, Winearls C, Winearls C, DI Giulio S, Galle J, Kiss I, Herlitz H, Wirnsberger G, Claes K, Suranyi M, Guerin A, Addison J, D'souza M, Fouqueray B, Floris M, Conti M, Cao R, Pili G, Melis P, Matta V, Murgia E, Atzeni A, Binda V, Angioi A, Peri M, Pani A, Besarab A, Belo D, Diamond S, Martin E, Sun C, Lee T, Saikali K, Franco M, Leong R, Neff T, Yu KHP, Tiranathanagul K, Praditpornsilpa K, Katavetin P, Kanjanabuch T, Avihingsanon Y, Tungsanga K, Eiam-Ong S, Macdougall IC, Casadevall N, Percheson P, Potamianou A, Foucher A, Fife D, Vercammen E. Renal anaemia - CKD 1-5. Nephrol Dial Transplant 2012. [DOI: 10.1093/ndt/gfs217] [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] [Indexed: 11/14/2022] Open
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7
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Chantrel F, Parienti JJ, Faller B, Lino-Daniel M, Hourmant M. Facteurs associés à la prescription d’EPO chez les insuffisants rénaux chroniques non dialysés : étude observationnelle chez 416 patients issus de la cohorte française DIVA-NEPH (Colmar). Nephrol Ther 2011. [DOI: 10.1016/j.nephro.2011.07.023] [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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8
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Belizna C, Loufrani L, Subra JF, Godin M, Jolly P, Vitecocq O, Faller B, Ghali A, Tron F, Hamidou M, Henrion D, Lévesque H, Ifrah N. A 5-year prospective follow-up study in essential cryofibrinogenemia patients. Autoimmun Rev 2011; 10:559-62. [PMID: 21549859 DOI: 10.1016/j.autrev.2011.04.009] [Citation(s) in RCA: 18] [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] [Received: 03/12/2011] [Accepted: 04/14/2011] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Cryofibrinogenemia may be essential, or secondary to diseases such as neoplasia, infection, thrombosis, and collagen vascular diseases. In a previous study, we reported the occurrence of neoplasia in some essential cryofibrinogenemia patients after a short period of follow-up. PURPOSE We performed a prospective multi-center 5-year follow-up study in essential cryofibrinogenemia patients (2005-2009). RESULTS 23 patients with essential cryofibrinogenemia were included, mean age 59 years (range: 33-79), 14 males. After a mean follow-up period of 24 months, 11/23 (47%) of cases that were initially diagnosed as essential cryofibrinogenemia were found to have an underlying lymphoma (6 T lymphoma and 5 B lymphoma). CONCLUSION This prospective study suggests that some cases of cryofibrinogenemia that are initially considered as essential, may have underlying lymphoma. Thus, we further suggest that regular follow-up should be performed in patients with essential cryofibrinogenemia.
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Affiliation(s)
- C Belizna
- Internal Medicine Department, University Hospital Angers, 4 rue Larrey, 49000 Angers, France.
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Belizna C, Godin M, Joly P, Vittecoq O, Hamidou M, Faller B, Lévesque H. Étude prospective à cinq ans de 21 cas de cryofibrinogénémie essentielle. Rev Med Interne 2010. [DOI: 10.1016/j.revmed.2010.03.428] [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: 12/01/2022]
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10
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Belizna C, Hamidou M, Faller B, Blaison G, Lavigne C, Godin M, Marie I, Thuillez C, Levesque H. Cryofibrinogénémie et insuffisance rénale. Rev Med Interne 2009. [DOI: 10.1016/j.revmed.2009.03.118] [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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11
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Faller B, Zhang J, Picus J. Anticoagulation and cardiac tamponade: Is there a relationship? J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.9562] [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: 11/20/2022] Open
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12
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Alenabi F, Genestier S, Verger C, Duman M, Faller B. Quelle modalité de suppléance chez les patients très âgés : la dialyse péritonéale ? Nephrol Ther 2007. [DOI: 10.1016/s1769-7255(07)78757-6] [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: 11/15/2022]
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13
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Mettauer B, Bellmont S, Epailly E, Faller B, Doutreleau S, Woehl-Jaegle ML, Ellero B, Wolf P, Cinqualbre J, Eisenmann B, Kretz JG, Kieny R. First European combined heart, kidney, and pancreas transplantation 11 years after. Transplant Proc 2001; 33:3496-8. [PMID: 11750494 DOI: 10.1016/s0041-1345(01)02413-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- B Mettauer
- Services of Cardiovascular Surgery, University Hospital, Strasbourg, France.
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Abstract
This study reports on a novel, high-throughput assay, designed to predict passive, transcellular permeability in early drug discovery. The assay is carried out in 96-well microtiterplates and measures the ability of compounds to diffuse from a donor to an acceptor compartment which are separated by a 9-10 microm hexadecane liquid layer. A set of 32 well-characterized, chemically diverse drugs was used to validate the method. The permeability values derived from the flux factors between donor and acceptor compartments show a good correlation with gastrointestinal absorption in humans. For comparison, correlations based on experimental or calculated octanol/water distribution coefficients (log D(o/w,6.8)) were significantly lower. In addition, this simple and robust assay allows determination of pH permeability profiles, critical information to predict gastrointestinal absorption of ionizable drugs and difficult to obtain from cell culture experiments. Correction for the unstirred water layer effect allows to differentiate between effective and intrinsic membrane permeability and opens up the dynamic range of the method. In addition, alkane/water partition coefficients can be derived from intrinsic membrane permeabilities, making this assay the first high-throughput method able to measure alkane/water log P in the microtiterplate format.
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Affiliation(s)
- F Wohnsland
- Novartis Pharma AG, WKL-122.P.33, CH-4002 Basel, Switzerland
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15
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Faller B, Spanka C, Sergejew T, Tschinke V. Improving the oral bioavailability of the iron chelator HBED by breaking the symmetry of the intramolecular H-bond network. J Med Chem 2000; 43:1467-75. [PMID: 10780902 DOI: 10.1021/jm990261n] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [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: 11/30/2022]
Abstract
Physicochemical analysis and Monte Carlo simulations were used to identify structural features which prevent oral absorption of HBED, a potent iron chelator. In water the dominant conformations of HBED involve the hydrophobic collapse of the two aromatic rings. These conformations are favored in polar media because they expose the polar phenolic hydroxy groups to the solvent and partially shield the nonpolar aromatic rings. In a less polar solvent such as chloroform, a symmetrical H-bond network between the carboxylates and the amines dominates the conformational space. This leads to the exposure of the phenolic hydroxy groups to the solvent, which is unfavorable for solvation. The low solubility of HBED in nonpolar solvents was confirmed experimentally by determination of the partition coefficients in octanol, chloroform, and cyclohexane and may explain the poor membrane permeability of this compound. The high conformational stability which disfavors partitioning into phospholipids is mainly due to the symmetrical H-bond network. Potentiometric titrations of a monoester of HBED in MeOH/water indicate that the protonation sequence was changed compared to that of the parent compound, suggesting that the symmetrical H-bond network was disrupted. Conformational analysis in chloroform confirmed that, in contrast to HBED, no symmetric interaction between the carboxylate and the nitrogen amines is possible in the half-ester and a variety of conformations which allow partial shielding of the polar phenolic OH groups are energetically possible. This theoretical model predicting a better solubility of the half-esters in nonpolar solvents was supported by the large increase in the partition coefficients in octanol, chloroform, and cyclohexane measured experimentally. The high absorbability predicted by physicochemical and computer simulation methods was corroborated by in vivo experiments in marmoset monkeys where the monoethyl ester derivative of HBED was well-absorbed orally while the parent compound was nearly ineffective in the same model.
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Affiliation(s)
- B Faller
- Research Department, Novartis Pharma AG, WKL-122.P.33, CH-4002 Basel, Switzerland.
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16
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Abstract
The long form of human uncoupling protein-3 (hUCP3L) is highly homologous to thermogenin (UCPI), the uncoupling protein of brown fat mitochondria, but is expressed predominantly in skeletal muscle. Its putative role is to regulate the coupling efficiency of oxidative phosphorylation and thus thermogenesis in skeletal muscle, a major thermogenic tissue in higher mammals. To study the functional relevance of hUCP3L, the protein was expressed in yeast cells under the control of the galactose promoter. Expression of hUCP3L induced a series of phenotype changes in the yeast cells. The cellular growth and the mitochondrial membrane potential were both diminished. The portion of cellular respiration coupled to oxidative phosphorylation decreased from 57% to 11% (P<0.001) and the cellular heat production, as measured by direct microcalorimetry, was increased by 33.3 +/- 3.2% (P<0.001) after induction of UCP3L. These observations demonstrate for the first time the intrinsic thermogenic properties of hUCP3L in intact cells.
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Affiliation(s)
- W Hinz
- Department of Metabolic and Cardiovascular Disease, Novartis Pharma AG, Basel, Switzerland
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17
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Lowther N, Fox R, Faller B, Nick H, Jin Y, Sergejew T, Hirschberg Y, Oberle R, Donnelly H. In vitro and in situ permeability of a 'second generation' hydroxypyridinone oral iron chelator: correlation with physico-chemical properties and oral activity. Pharm Res 1999; 16:434-40. [PMID: 10213376 DOI: 10.1023/a:1018886005136] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE The in vitro and in situ transport of CGP 65015 ((+)-3-hydroxy-1-(2-hydroxyethyl)-2-hydroxyphenyl-methyl-1H-pyridin-4-on e), a novel oral iron chelator, is described. The predictive power of these data in assessing intestinal absorption in man is described. METHODS Caco-2 epithelial monolayer and in situ rat jejunum perfusion intestinal permeability models were utilized. In vivo iron excretion and preliminary animal pharmacokinetic experiments were described. Ionization constants and octanol/aqueous partition coefficients were measured potentiometrically. Solubilities and intrinsic dissolution rates were determined using standard procedures. RESULTS Caco-2 cell (Papp approximately 0.25 x 10(-6) cm x s(-1)) and rat jejunum (Pw approximately 0.4) permeabilities of CGP 65015 were determined. The log D(pH 7.4) of CGP 65015 was 0.58 and its aqueous solubility was < 0.5 mg x ml(-1) (pH 3-9). The intrinsic dissolution rate of CGP 65015 in USP simulated intestinal fluid was 0.012 mg x min(-1) x cm(-2). CGP 65015 promotes iron excretion effectively and dose dependently in animals. CONCLUSIONS Caco-2 and rat intestinal permeabilities predict incomplete oral absorption of CGP 65015 in man. Preliminary rat pharmacokinetics support this. Physico-chemical data are, also, in line and suggest that CGP 65015 may, in addition, be solubility/dissolution rate limited in vivo. Nevertheless, early animal pharmacological data demonstrate that CGP 65015 is a viable oral iron chelator candidate.
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Affiliation(s)
- N Lowther
- Pharmaceutical and Analytical Development, Novartis Horsham Research Centre, West Sussex, United Kingdom.
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18
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Lowther N, Tomlinson B, Fox R, Faller B, Sergejew T, Donnelly H. Caco-2 cell permeability of a new (hydroxybenzyl)ethylenediamine oral iron chelator: correlation with physicochemical properties and oral activity. J Pharm Sci 1998; 87:1041-5. [PMID: 9724552 DOI: 10.1021/js980191s] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This study describes the transport of CGP 75254A, a novel oral iron chelator, across Caco-2 cells in an attempt to model intestinal epithelial cell permeability in man. CGP 75254A was dosed to the apical side of Caco-2 cell monolayers, together with [14C]mannitol as an internal permeability standard. The apparent permeability (Papp) was calculated from the cumulative appearance of drug in the basolateral fluid with time. The [14C]mannitol Papp indicated that the Caco-2 monolayers remained intact and that the iron chelator was not toxic to the cells. Permeabilities of CGP 75254A were compared with the Caco-2 permeabilities of compounds of known absorption in man. The results predict that absorption of CGP 75254A is likely to be virtually complete at pH values between 5.5 and 7.0. However, at pH 8.0 permeability is predicted as negligible. Cell permeability data are in full accordance with key physicochemical properties of CGP 75254A and suggest that the drug is passively absorbed. The results, which suggest likely quantitative absorption in vivo, are supported by preliminary pharmacological experiments in marmosets.
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Affiliation(s)
- N Lowther
- Pharmaceutical and Analytical Development, Ciba Pharmaceuticals (now Novartis Horsham Research Centre), Wimblehurst Road, Horsham, West Sussex RH12 4AB, England.
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19
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Faller B. New peritoneal dialysis techniques and their evaluation. Adv Nephrol Necker Hosp 1997; 27:189-221. [PMID: 9408448] [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: 02/05/2023]
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20
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Faller B. [Peritoneal dialysis. Modalities and indications]. Soins 1997:8-10. [PMID: 9479212] [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: 02/06/2023]
Affiliation(s)
- B Faller
- Service de Néphrologie et de Dialyse, Hôpital Louis Pasteur, Colmar
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21
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Faller B, Chiron S, Freund G. [Peritoneal dialysis. Pre-dialysis information]. Soins 1997:11-2. [PMID: 9479213] [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: 02/06/2023]
Affiliation(s)
- B Faller
- Service de Néphrologie et de Dialyse, Hôpital Louis Pasteur, Colmar
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Faller B. [Peritoneal dialysis. Evaluation]. Soins 1997:36. [PMID: 9479218] [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: 02/06/2023]
Affiliation(s)
- B Faller
- Service de Néphrologie et de Dialyse, Hôpital Louis Pasteur, Colmar
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23
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Faller B. [Peritoneal dialysis]. Soins 1997:5. [PMID: 9479210] [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: 02/06/2023]
Affiliation(s)
- B Faller
- Service de Néphrologie et de Dialyse, Hôpital Louis Pasteur, Colmar
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24
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Faller B. [Peritoneal dialysis. Principles]. Soins 1997:6-7. [PMID: 9479211] [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: 02/06/2023]
Affiliation(s)
- B Faller
- Service de Néphrologie et de Dialyse, Hôpital Louis Pasteur, Colmar
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25
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Laforet M, Froelich N, Parissiadis A, Pfeiffer B, Schell A, Faller B, Woehl-Jaegle ML, Cazenave JP, Tongio MM. A nucleotide insertion in exon 4 is responsible for the absence of expression of an HLA-A*01 allele. Tissue Antigens 1997; 50:347-50. [PMID: 9349617 DOI: 10.1111/j.1399-0039.1997.tb02885.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
HLA class I typing performed in parallel by molecular biology and serology has revealed cases where an HLA class I allele was identified whereas the corresponding antigen was not detected on the cell surface. In the present report, we describe four members of a family in whom an HLA-A1 allele identified at the molecular level was typed as A "blank" by lymphocytotoxicity. This serologically blank antigen was undetectable by isoelectric focusing (IEF). Sequencing of the HLA-A*01 allele from the promoter region to the eighth exonic region revealed insertion of a "C" nucleotide at the beginning of the fourth exon as compared to the common HLA-A*0101 allele. This mutation causes a frame shift, giving rise to an early stop codon in the fourth exon.
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Affiliation(s)
- M Laforet
- Laboratoire d'Histocompatibilité Etablissement de Transfusion Sanguine, Strasbourg, France.
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26
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Cinqualbre J, Eisenmann B, Wolf P, Meyer C, Odeh M, Kretz JG, Charpentier A, Faller B, Jaegle ML, Boudjema K, Jaeck D, Pinget M, Altieri M, Ellero B, Fruh S, Kieny R. [An original case of simultaneous cardiac, pancreatic and renal transplantation. Results over 6 years]. Chirurgie 1997; 121:654-7. [PMID: 9138326] [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: 02/04/2023]
Abstract
Combined transplantation is actually performed on specific and rare indications. We are presenting here the results of a combined heart-kidney and pancreatic graft. It was performed in a patient presenting an idiopathic cardiomyopathy in end-stage failure and a post-diabetic nephropathy on dialysis. Today, organs function is quite satisfactory with a 6 year follow-up. Only one isolated heart rejection episode was observed at the 15th post-operative day. The patient has recovered a full-time professional activity at one year. This successful graft was obtained by an "homogeneous multiorgan approach" during all the pre-peri and postoperative time.
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Affiliation(s)
- J Cinqualbre
- Service de chirurgie générale et transplantation multi-organes H.U.S. et Fondation transplantation, Strasbourg
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27
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Faller B, Shockley T, Genestier S, Martis L. Polyglucose and amino acids: preliminary results. Perit Dial Int 1997; 17 Suppl 2:S63-7. [PMID: 9163800] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- B Faller
- Department of Nephrology, Civil Hospital, Colmar, France
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28
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Lameire N, Van Biesen W, Dombros N, Dratwa M, Faller B, Gahl GM, Gokal R, Krediet RT, La Greca G, Maiorca R, Matthys E, Ryckelynck JP, Selgas R, Walls J. The referral pattern of patients with ESRD is a determinant in the choice of dialysis modality. ARCH ESP UROL 1997; 17 Suppl 2:S161-6. [PMID: 9163820] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- N Lameire
- Renal Division, University Hospital, Ghent, Belgium
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29
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Faller B. Amino acid-based peritoneal dialysis solutions. Kidney Int Suppl 1996; 56:S81-S85. [PMID: 8914059] [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: 05/22/2023]
Affiliation(s)
- B Faller
- Service de Néphrologie, Hôpital Pasteur, Colmar, France
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30
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Genestier S, Hedelin G, Schaffer P, Faller B. Prognostic factors in CAPD patients: a retrospective study of a 10-year period. Nephrol Dial Transplant 1995; 10:1905-11. [PMID: 8592602] [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: 01/31/2023] Open
Abstract
A prognostic study was retrospectively performed on a cohort of 201 ESRD patients having started CAPD in one single centre between 1983 and 1993 (mean follow-up 24 months). At the end of the study 74 patients had died, 63 were transplanted, and 19 had been transferred to another dialysis modality. The purpose of the study was to estimate patient and technique survivals according to clinical and biological variables recorded at the beginning of the treatment. The authors decided to focus on the possible prognostic role of urea kinetic parameters which are still controversial in the literature. Concerning patient survival, the Cox proportional hazards model selected seven prognostic factors, including urea Kt/V (relative risk = 1.69). The division of the study group according to three levels of Kt/V (< or = 1.7, between 1.7 and 2.2, and > 2.2) allowed us to estimate 1.7 as an index of an adequate CAPD prescription. NPCR at the limit of significance for patient survival was clearly a prognostic factor for technique survival (relative risk = 2.50). Creatinine clearance was closely linked to both technique and patient survival (relative risk > 3). These three factors, in addition to the clinical and biological variables generally described in the literature, must be taken into account in the evaluation of a prognosis for CAPD.
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31
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Hellstern P, Moberg U, Ekblad M, Anders CU, Faller B, Müller S. In vitro characterization of antithrombin III concentrates--a single-blind study. Haemostasis 1995; 25:193-201. [PMID: 7557658 DOI: 10.1159/000217160] [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] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Twenty-three lots of five antithrombin III (AT III) concentrates from four manufacturers were analyzed in a single-blind study. All the preparations had been virus-inactivated by pasteurization, and one concentrate had also been treated with solvent/detergent (S/D). AT III activities were determined using two thrombin-based and one factor Xa-based chromogenic substrate assays. AT III antigen was measured by kinetic nephelometry. All AT III assays were tested against the first international reference preparation coded 72/1. In addition, AT III was characterized by crossed immunoelectrophoresis in the presence of heparin and by gel filtration. The following were quantified: heparin cofactor II activity and antigen content, heparin activity, thrombin-AT III complexes, AT III-protease complexes, total protein, albumin, immunoglobulins, glucose and pH. The AT III concentrates differed markedly in terms of their purity and potency. The specific activities of AT III and the ratios of AT III activity to antigen content ranged from 3.4 to 6.9 and from 0.63 to 0.84, respectively. The highest values were found in five lots of the concentrate that had been treated by both pasteurization and S/D. This preparation was the only one that was virtually free of denaturated AT III, as judged by crossed immunoelectrophoresis. Marked batch-to-batch variation in AT III potencies was found in two out of the five preparations analyzed. In two out of five lots from one manufacturer, the measured potencies were more than 10% lower than the declared potencies.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P Hellstern
- Institute of Transfusion Medicine and Immunohematology, Klinikum Ludwigshafen am Rhein, Germany
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32
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Faller B, Cadène M, Bieth JG. Demonstration of a two-step reaction mechanism for the inhibition of heparin-bound neutrophil elastase by alpha 1-proteinase inhibitor. Biochemistry 1993; 32:9230-5. [PMID: 8369290 DOI: 10.1021/bi00086a031] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [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
Heparin decreases the rate of inhibition of neutrophil elastase by alpha 1-proteinase inhibitor as a result of its strong binding to the enzyme. Here, we used the slow-binding kinetic approach to decide whether the enzyme-inhibitor interaction proceeds via a two-step mechanism and to identify the step that is affected by heparin. The inhibition kinetics was assessed under pseudo-first-order conditions using conventional or stopped-flow spectrophotometry. In the absence of heparin, the pseudo-first-order rate constant of inhibition increased linearly with the inhibitor concentration indicating that within the experimental concentration range (< or = 6 microM) the enzyme-inhibitor association conforms either to a simple bimolecular reaction (E+I kass-->EI with kass = 10(7) M-1 s-1) or to a two-step reaction (E+I Ki*<==>EI* k2-->EI with Ki* > 0.4 microM and k2 > 4 s-1). In the presence of heparin, the rate constant of inhibition varied hyperbolically with the inhibitor concentration, indicating that the inhibition is a two-step process with Ki* = 80 nM and K2 = 0.15 s-1. Thus, heparin has two opposite effects on the elastase + alpha 1-proteinase inhibitor interaction: it favors the association by decreasing Ki* but impairs it by decreasing k2. This rationalizes the previously demonstrated rate-depressing effect of the sulfated polymer. Heparin does not significantly alter the stability of the irreversible elastase-alpha 1-proteinase inhibitor complex.
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Affiliation(s)
- B Faller
- Laboratoire d'Enzymologie, INSERM Unité 237, Université Louis Pasteur de Strasbourg, Illkirch, France
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33
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Faller B, Slingeneyer A, Waller M, Michel C, Grützmacher P, Müller HP, Barany P, Grabensee B, Issad B, Schmitt H. Daily subcutaneous administration of recombinant human erythropoietin (rhEPO) in peritoneal dialysis patients: a European dose-response study. Clin Nephrol 1993; 40:168-75. [PMID: 8403573] [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: 01/30/2023] Open
Abstract
In a prospective randomized open multicenter study, 107 anemic (Hct < = 28%) peritoneal dialysis (PD) patients were treated with s.c. rhEPO daily. The mean observation period was 299 days (range 14-479 days). Patients were randomly assigned to 3 groups with different initial doses: 5 U/kg (G5), 10 U/kg (G10), 20 U/kg (G20). Initial doses were maintained for at least 8 weeks unless the target Hct (30-35%) was achieved earlier. The weekly increase of Hct was significantly (p < 0.05) dose-dependent: 0.19% in G5, 0.5% in G10 and 0.94% in G20. In case of insufficient response (< 0.5% per week), the dose was doubled every 4 weeks. Final doses on achieving the target Hct ranged from 5 to 40 U/kg (median 20 U/kg). The dose was then reduced to 50% and adjusted individually. The median maintenance dose was 9.9 U/kg/day. No tendency towards higher blood pressure or intensification of antihypertensive treatment was observed. When rhEPO is administered daily, 10 U/kg/day (70 U/kg weekly) is the recommended starting dose. The need for higher doses used in unsatisfactory response, should lead to further examination to rule out iron deficiency and other reasons for non-response. The median maintenance dose reported here is the lowest published in the literature for PD patients and seems to be linked to the daily injections.
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Affiliation(s)
- B Faller
- Hôpital Louis-Pasteur, Service de Néphrologie-Hemodialyse, Colmar, France
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Abstract
A microsomal preparation of human prostatic tissue was used to study the kinetics of interaction of steroid 5 alpha-reductase with finasteride, a known 5 alpha-reductase inhibitor. This molecule has been reported to reversibly bind 5 alpha-reductase in a competitive manner to testosterone with a Ki value in the 10 nM range. The results presented in this paper show that enzyme-inhibitor complex formation does not take place instantaneously as assumed in previous studies. At neutral pH and 37 degrees C, the association of enzyme with inhibitor is governed by a rate constant, kon, of 2.7 x 10(5) M-1 s-1. This low kon value, in combination with the high energy of activation of the association reaction (150 kJ mol-1), indicates that the association process is not diffusion controlled and may proceed through intermediate steps. However, such an intermediate was not detected kinetically under the inhibitor concentrations investigated. We therefore conclude that the equilibrium dissociation constant, Ki*, for the initial binding of the enzyme to the inhibitor is higher than 1.5 x 10(7) M. Even at inhibitor concentrations as low as 1 nM, the reaction was completely displaced to the EI complex and no residual activity detected once the equilibrium was reached. Hence, the interaction between finasteride and 5 alpha-reductase can also be characterized by a very low overall equilibrium dissociation constant (Ki << 10(-9) M), at least 1 order of magnitude lower than previously reported values.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- B Faller
- Pharma Research Division, Ciba-Geigy Ltd., Basel, Switzerland
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35
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Abstract
Low molecular mass heparin (5.1 kDa) forms a tight complex with mucus proteinase inhibitor, the physiologic neutrophil elastase inhibitor of the upper respiratory tract. This binding strongly enhances the intrinsic fluorescence of the inhibitor and the rate of neutrophil elastase inhibitor association. One mole of this heparin fragment binds 1 mol of inhibitor with a Kd of 50 nM. From the variation of Kd with ionic strength, it is inferred that (i) 85% of the heparin--inhibitor binding energy i due to electrostatic interactions, (ii) about seven ionic interactions are involved in heparin--inhibitor binding. strength, it is inferred that (i) 85% of the heparin--inhibitor binding energy is due to electrostatic interactions, (ii) about seven ionic interactions are involved in heparin--inhibitor binding. and (iii), about one-third of low quantum yield of Trp30, the single tryptophan residue of the inhibitor, blue-shifts its maximum emission wavelength by 6 nm, decreases the acrylamide quenching rate constant by a factor of 4, and increases the mean intensity weighted lifetime by a factor of 2.5. These important spectroscopic changes evidence a heparin--induced conformational change of the inhibitor which buries Trp30 in a very hydrophobic environment. Heparin accelerates the inhibition of elastase in a concentration-dependent manner. When both enzyme and inhibitor are saturated by the polymer, the second-order association rate constant is 7.7 x 10(7) M-1 s-1, a value that is 27-fold higher than that measured with the free partners. This finding may have important physiologic and therapeutic bearing.
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Affiliation(s)
- B Faller
- Laboratoire d'Enzymologie, INSERM Unité 237, Université Louis Pasteur de Strasbourg, Illkirch, France
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36
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Faller B, Frommherz K, Bieth JG. Heparin interferes with the inhibition of neutrophil elastase by its physiological inhibitors. Biol Chem Hoppe Seyler 1992; 373:503-8. [PMID: 1515082 DOI: 10.1515/bchm3.1992.373.2.503] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Heparin depresses the second-order rate constant kass for the inhibition of neutrophil elastase by alpha 1-proteinase inhibitor. For high and low molecular weight heparin the decrease in kass is 290-fold and 40-fold, respectively. This is due to a tight binding of the polymer to elastase: Kd = 3.3 nM or 89 nM for high or low molecular weight heparin respectively. In contrast heparin increases the rate of inhibition of elastase by mucus proteinase inhibitor. For low molecular weight heparin, there is a 27-fold increase in kass. This is due to a strong binding of the polymer to the inhibitor (Kd = 50 nM) which undergoes a conformational change.
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Affiliation(s)
- B Faller
- Université Louis Pasteur de Strasbourg, INSERM U 237, Laboratoire d'Enzymologie, Faculté de Pharmacie, Illkirch, France
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37
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Marichal JF, Brunel P, Lecaillon JB, Godbillon J, Faller B, Brignon P, Ménard J. Pharmacokinetics of cadralazine and its hydrazino-metabolite in patients with renal impairment after repeated administration of 5 mg once daily. Eur J Drug Metab Pharmacokinet 1992; 17:213-20. [PMID: 1490491 DOI: 10.1007/bf03190148] [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: 12/27/2022]
Abstract
Since the hydrazino-pyridazine metabolite of cadralazine, CGP 22 639 is believed to contribute to the activity of the drug, its pharmacokinetics and that of cadralazine were investigated in 8 hypertensive patients with renal impairment. The creatinine clearance (CLcr) of patients ranged from 10 to 60 ml/min. The concentrations of cadralazine in plasma and urine, and of CGP 22 639 (plus its possible hydrazones) in plasma were measured after single and repeated administration of 5 mg of cadralazine once daily. A hypotension possibly linked to cadralazine treatment was recorded on day 3 for the patient with CLcr = 10 ml/min. Metabolite concentrations were found to be at least twice as high as in other patients indicating that in this patient, the daily dose of 5 mg was probably too high. The pharmacokinetics of cadralazine were not modified by repeated administration. The drug and its metabolite were eliminated more slowly in patients with low creatinine clearance. The t1/2 of CGP 22 639 was about twice the t1/2 of the unchanged drug. In patients whose CLcr ranged from 19-37 ml/min the mean accumulation factor of apparent CGP 22 639 was 1.7 times that of the unchanged drug. It shows that the apparent CGP 22 639 accumulated more than the unchanged drug. A starting daily dose of 2.5 mg of cadralazine in patients with CLcr < 40 ml/min appears to be suited to take into account the pharmacokinetics of CGP 22 639. This dose can be increased by 2.5 mg steps if the antihypertensive effect is not sufficient (maximum dose with CLcr < 40 ml/min: 10 mg).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J F Marichal
- Service de Néphrologie et d'hémodialyse, Hôpital Louis Pasteur, Colmar, France
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Abstract
The kinetics of binding of recombinant eglin c to bovine pancreatic chymotrypsin was studied by conventional and stopped-flow techniques. With nanomolar enzyme and inhibitor concentrations, the inhibition was fast and pseudo-irreversible (k(assoc.) = 4 x 10(6) m-1.s-1 at 7.4 and 25 degrees C). Reaction of the enzyme-inhibitor complex with alpha 1-proteinase inhibitor, an irreversible chymotrypsin ligand, resulted in a slow release of free eglin c, which was monitored by electrophoresis (k(dissoc.) approximately 1.6 x 10(-6) s-1, t1/2 approximately 5 days). The proflavin displacement method and a stopped-flow apparatus were used to monitor the association of chymotrypsin with eglin c under a wide range of inhibitor concentration and under pseudo-first-order conditions. At pH 7.4 and 25 degrees C or 5 degrees C, or at pH 5.0 and 25 degrees C, the pseudo-first-order rate constant of proflavin displacement increased linearly with eglin c up to the highest concentration tested, suggesting a one-step bimolecular association reaction: E + I in equilibrium with EI. However, kassoc. is much lower than the rate constant for a bimolecular reaction and its activation energy (66 kJ.mol-1 at pH 7.4 and 78 kJ.mol-1 at pH 5.0) is far too high for a diffusion-controlled step. The enzyme-inhibitor association may therefore occur via a loose pre-equilibrium complex EI* (Ki* much greater than 5 x 10(-4) M) that rapidly isomerizes (k2 much greater than 2 x 10(3) s-1) into an extremely stable final complex (Ki approximately 4 x 10(-13) M). Unlike other proteinase-inhibitor systems, the chymotrypsin-eglin association is virtually pH-independent.
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Affiliation(s)
- B Faller
- INSERM U 237, Université Louis Pasteur de Strasbourg, Illkirch, France
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39
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Frommherz KJ, Faller B, Bieth JG. Heparin strongly decreases the rate of inhibition of neutrophil elastase by alpha 1-proteinase inhibitor. J Biol Chem 1991; 266:15356-62. [PMID: 1869557] [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: 12/29/2022] Open
Abstract
Heparin depresses the second-order rate constant ka for the inhibition of neutrophil elastase by alpha 1-proteinase inhibitor. High molecular mass heparin decreases ka from 1.3 x 10(7) M-1 s-1 to a limit of 4.6 x 10(4) M-1 s-1. Low molecular mass heparin is about 7-fold less effective. Dermatan sulfate and chondroitin sulfate are less efficient. Heparin preparations used in clinical care also strongly depress ka when tested at concentrations corresponding to their clinical efficacy. Heparin also decreases the ka for the elastase/eglin c and the cathepsin G/alpha 1-proteinase inhibitor systems but not that for the alpha 1-proteinase inhibitor/pancreatic elastase or trypsin pairs. These results, together with Sepharose-heparin binding studies, indicate that the ka-depressing effect of the polymer is related to its ability to form a tight complex with elastase but not with alpha 1-proteinase inhibitor. One mol of high molecular mass heparin binds 3 mol of neutrophil elastase with a Kd of 3.3 nM. Low molecular mass heparin binds elastase with a 1:1 stoichiometry and a Kd of 89 nM. For both heparins ka is lowest when elastase is fully saturated with heparin. From this we conclude that heparin decreases ka, because the heparin-elastase complex is able to slowly react with alpha 1-proteinase inhibitor and not because the inhibitor slowly dissociates the heparin-elastase complex. These findings may have important pathophysiological bearing.
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Affiliation(s)
- K J Frommherz
- Laboratoire d'Enzymologie, Institut National de la Santé et de la Recherche Médicale U 237, Université Louis Pasteur de Strasbourg, Illkirch, France
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40
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Frommherz K, Faller B, Bieth J. Heparin strongly decreases the rate of inhibition of neutrophil elastase by alpha 1-proteinase inhibitor. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)98623-0] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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41
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Faller B. [Continuous ambulatory peritoneal dialysis. Basic principles]. Soins 1991:14-9. [PMID: 1948182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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42
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Faller B. [Continuous ambulatory peritoneal dialysis. Indications]. Soins 1991:20, 22. [PMID: 1948183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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43
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Faller B. [Kidney, kidney function, renal insufficiency]. Soins 1991:6-8. [PMID: 1948194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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44
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Hovan T, Faller B. [Surveillance of patients treated by CAPD]. Soins 1991:41-7. [PMID: 1948189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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45
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Faller B. [Continuous ambulatory peritoneal dialysis]. Soins 1991:3-4. [PMID: 1948186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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46
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Faller B. [Treatment of chronic renal insufficiency]. Soins 1991:10-2. [PMID: 1948181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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47
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Faller B. [Peritoneal dialysis. Conclusion]. Soins 1991:57-8. [PMID: 1948192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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48
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Faller B. [Continuous ambulatory peritoneal dialysis]. Rev Prat 1991; 41:1080-4. [PMID: 2052868] [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: 12/30/2022]
Abstract
In contrast with hemodialysis (HD) Continuous Ambulatory Peritoneal Dialysis (CAPD) is a permanent dialysis procedure proposed to the chronic renal patients. Through a permanent peritenoal catheter the patients exchange 2 litres of dialysate 4 times a day, 7 days a week, as soon as the dialysat/plasma concentration for urea reaches 1. Inflow and outflow of the fluid is obtained by gravity, without machine. The short term survival rate is comparable between HD and CAPD. After 5 years, some patients, loosing the residual renal function, need to increase the possibilities of CAPD. The recent disconnect systems reduce the rate of peritonitis down to 1 episode every 36 months. With the actual technology the severe complications such as sclerosing peritonitis decrease or even disappear. Maintenance of an adequate nutritional status in the patients remains an often difficult problem. CAPD may be proposed to nearly all the patients who prefer to be treated at home: children, working adults, diabetics and elderly. Long term studies are still needed to follow the peritoneal performances over time.
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Affiliation(s)
- B Faller
- Service de néphrologie, hôpital L. Pasteur, Colmar
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49
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Abstract
Recombinant eglin c is a potent reversible inhibitor of human pancreatic elastase. At pH 7.4 and 25 degrees C, kass. = 7.3 x 10(5) M-1.s-1, kdiss. = 2.7 x 10(-4) s-1 and Ki = 3.7 x 10(-10) M. Stopped-flow kinetic indicate that the formation of the stable enzyme-inhibitor complex is not preceded by a fast pre-equilibrium complex or that the latter has a dissociation constant greater than 0.3 microM. The elastase-eglin c complex is much less stable at pH 5.0 and 25 degrees C, where kdiss. = 1.1 x 10(-2) s-1 and Ki = 7.3 x 10(-8) M. At pH 7.4 the activation energy for kass. is 43.9 kJ.mol-1 (10.5 kcal.mol-1). The kass. increases between pH 5.0 and 8.0 and remains essentially constant up to pH 9.0. This pH-dependence could not be described by a simple ionization curve. Both alpha 2-macroglobulin and alpha 1-proteinase inhibitor are able to dissociate the elastase-eglin c complex, as evidenced by measurement of the enzymic activity of alpha 2-macroglobulin-bound elastase or by polyacrylamide-gel electrophoresis of mixtures of alpha 1-proteinase inhibitor and elastase-eglin c complex. The rough estimate of kdiss. obtained with the alpha 2-macroglobulin dissociation experiment (1.6 x 10(-4) s-1) was of the same order of magnitude as the constant measured with the progress curve method. Eglin c strongly inhibits the solubilization of human aorta elastin by human pancreatic elastase. The extent of inhibition is the same whether elastase is added to a suspension of elastin and eglin c or whether elastase is preincubated with elastin for 3 min before addition of eglin c. However, the efficiency of the inhibitor sharply decreases if elastase is reacted with elastin for more prolonged periods.
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Affiliation(s)
- B Faller
- I.N.S.E.R.M. Unité 237, Faculté de Pharmacie, Université Louis Pasteur de Strasbourg, Illkirch, France
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