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Kostadinova R, Ströbel S, Chen L, Fiaschetti-Egli K, Gadient J, Pawlowska A, Petitjean L, Bieri M, Thoma E, Petitjean M. Digital pathology with artificial intelligence analysis provides insight to the efficacy of anti-fibrotic compounds in human 3D MASH model. Sci Rep 2024; 14:5885. [PMID: 38467661 PMCID: PMC10928082 DOI: 10.1038/s41598-024-55438-2] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 02/23/2024] [Indexed: 03/13/2024] Open
Abstract
Metabolic dysfunction-associated steatohepatitis (MASH) is a severe liver disease characterized by lipid accumulation, inflammation and fibrosis. The development of MASH therapies has been hindered by the lack of human translational models and limitations of analysis techniques for fibrosis. The MASH three-dimensional (3D) InSight™ human liver microtissue (hLiMT) model recapitulates pathophysiological features of the disease. We established an algorithm for automated phenotypic quantification of fibrosis of Sirius Red stained histology sections of MASH hLiMTs model using a digital pathology quantitative single-fiber artificial intelligence (AI) FibroNest™ image analysis platform. The FibroNest™ algorithm for MASH hLiMTs was validated using anti-fibrotic reference compounds with different therapeutic modalities-ALK5i and anti-TGF-β antibody. The phenotypic quantification of fibrosis demonstrated that both reference compounds decreased the deposition of fibrillated collagens in alignment with effects on the secretion of pro-collagen type I/III, tissue inhibitor of metalloproteinase-1 and matrix metalloproteinase-3 and pro-fibrotic gene expression. In contrast, clinical compounds, Firsocostat and Selonsertib, alone and in combination showed strong anti-fibrotic effects on the deposition of collagen fibers, however less pronounced on the secretion of pro-fibrotic biomarkers. In summary, the phenotypic quantification of fibrosis of MASH hLiMTs combined with secretion of pro-fibrotic biomarkers and transcriptomics represents a promising drug discovery tool for assessing anti-fibrotic compounds.
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Affiliation(s)
| | - Simon Ströbel
- InSphero AG, Wagistrasse 27A, Schlieren, Switzerland
| | - Li Chen
- PharmaNest, Princeton, NJ, USA
| | | | - Jana Gadient
- InSphero AG, Wagistrasse 27A, Schlieren, Switzerland
| | | | | | - Manuela Bieri
- InSphero AG, Wagistrasse 27A, Schlieren, Switzerland
| | - Eva Thoma
- InSphero AG, Wagistrasse 27A, Schlieren, Switzerland
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Ratziu V, Hompesch M, Petitjean M, Serdjebi C, Iyer JS, Parwani AV, Tai D, Bugianesi E, Cusi K, Friedman SL, Lawitz E, Romero-Gómez M, Schuppan D, Loomba R, Paradis V, Behling C, Sanyal AJ. Artificial intelligence-assisted digital pathology for non-alcoholic steatohepatitis: current status and future directions. J Hepatol 2024; 80:335-351. [PMID: 37879461 DOI: 10.1016/j.jhep.2023.10.015] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 08/28/2023] [Accepted: 10/09/2023] [Indexed: 10/27/2023]
Abstract
The worldwide prevalence of non-alcoholic steatohepatitis (NASH) is increasing, causing a significant medical burden, but no approved therapeutics are currently available. NASH drug development requires histological analysis of liver biopsies by expert pathologists for trial enrolment and efficacy assessment, which can be hindered by multiple issues including sample heterogeneity, inter-reader and intra-reader variability, and ordinal scoring systems. Consequently, there is a high unmet need for accurate, reproducible, quantitative, and automated methods to assist pathologists with histological analysis to improve the precision around treatment and efficacy assessment. Digital pathology (DP) workflows in combination with artificial intelligence (AI) have been established in other areas of medicine and are being actively investigated in NASH to assist pathologists in the evaluation and scoring of NASH histology. DP/AI models can be used to automatically detect, localise, quantify, and score histological parameters and have the potential to reduce the impact of scoring variability in NASH clinical trials. This narrative review provides an overview of DP/AI tools in development for NASH, highlights key regulatory considerations, and discusses how these advances may impact the future of NASH clinical management and drug development. This should be a high priority in the NASH field, particularly to improve the development of safe and effective therapeutics.
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Affiliation(s)
- Vlad Ratziu
- Sorbonne Université, ICAN Institute for Cardiometabolism and Nutrition, Hospital Pitié-Salpêtrière, INSERM UMRS 1138 CRC, Paris, France.
| | | | | | | | | | - Anil V Parwani
- Department of Pathology, The Ohio State University, Columbus, OH, USA
| | | | | | - Kenneth Cusi
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA
| | - Scott L Friedman
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Eric Lawitz
- Texas Liver Institute, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Manuel Romero-Gómez
- Hospital Universitario Virgen del Rocío, CiberEHD, Insituto de Biomedicina de Sevilla (HUVR/CSIC/US), Universidad de Sevilla, Seville, Spain
| | - Detlef Schuppan
- Institute of Translational Immunology and Department of Medicine, University Medical Center, Mainz, Germany; Department of Hepatology and Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Rohit Loomba
- NAFLD Research Center, University of California at San Diego, San Diego, CA, USA
| | - Valérie Paradis
- Université Paris Cité, Service d'Anatomie Pathologique, Hôpital Beaujon, Paris, France
| | | | - Arun J Sanyal
- Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University, Richmond, VA, USA
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Watson A, Petitjean L, Petitjean M, Pavlides M. Liver fibrosis phenotyping and severity scoring by quantitative image analysis of biopsy slides. Liver Int 2024; 44:399-410. [PMID: 38010988 DOI: 10.1111/liv.15768] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/21/2023] [Accepted: 10/08/2023] [Indexed: 11/29/2023]
Abstract
BACKGROUND & AIMS Digital pathology image analysis can phenotype liver fibrosis using histological traits that reflect collagen content, morphometry and architecture. Here, we aimed to calculate fibrosis severity scores to quantify these traits. METHODS Liver biopsy slides were categorised by Ishak stage and aetiology. We used a digital pathology technique to calculate four fibrosis severity scores: Architecture Composite Score (ACS), Collagen Composite Score (CCS), Morphometric Composite Score (MCS) and Phenotypic Fibrosis Composite Score (PH-FCS). We compared how these scores varied according to disease stage and aetiology. RESULTS We included 80 patients (40% female, mean age 59.0 years, mean collagen proportionate area 17.1%) with mild (F0-2, n = 28), moderate (F3-4, n = 17) or severe (F5-6, n = 35) fibrosis. All four aetiology independent scores corelated with collagen proportionate area (ACS: rp = .512, CCS: rp = .727, MCS: rp = .777, PFCS: r = .772, p < .01 for all) with significant differences between moderate and severe fibrosis (p < .05). ACS increased primarily between moderate and severe fibrosis (by 95% to 226% depending on underlying aetiology), whereas MCS and CCS accumulation was more varied. We used 28 qFTs that distinguished between autoimmune- and alcohol-related liver disease to generate an MCS that significantly differed between mild and severe fibrosis for these aetiologies (p < .05). CONCLUSIONS We describe four aetiology-dependent and -independent severity scores that quantify fibrosis architecture, collagen content and fibre morphometry. This approach provides additional insight into how progression of architectural changes and accumulation of collagen may differ depending on underlying disease aetiology.
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Affiliation(s)
- Adam Watson
- Medical Sciences Division, University of Oxford, Oxford, UK
| | | | | | - Michael Pavlides
- Translational Gastroenterology Unit, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford NIHR Biomedical Research Centre, University of Oxford, Oxford, UK
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Inia JA, Stokman G, Morrison MC, Worms N, Verschuren L, Caspers MPM, Menke AL, Petitjean L, Chen L, Petitjean M, Jukema JW, Princen HMG, van den Hoek AM. Semaglutide Has Beneficial Effects on Non-Alcoholic Steatohepatitis in Ldlr-/-.Leiden Mice. Int J Mol Sci 2023; 24:ijms24108494. [PMID: 37239841 DOI: 10.3390/ijms24108494] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/04/2023] [Accepted: 05/07/2023] [Indexed: 05/28/2023] Open
Abstract
Semaglutide, a glucagon-like peptide-1 receptor agonist, is an antidiabetic medication that has recently been approved for the treatment of obesity as well. Semaglutide is postulated to be a promising candidate for the treatment of non-alcoholic steatohepatitis (NASH). Here, Ldlr-/-.Leiden mice received a fast-food diet (FFD) for 25 weeks, followed by another 12 weeks on FFD with daily subcutaneous injections of semaglutide or vehicle (control). Plasma parameters were evaluated, livers and hearts were examined, and hepatic transcriptome analysis was performed. In the liver, semaglutide significantly reduced macrovesicular steatosis (-74%, p < 0.001) and inflammation (-73%, p < 0.001) and completely abolished microvesicular steatosis (-100%, p < 0.001). Histological and biochemical assessment of hepatic fibrosis showed no significant effects of semaglutide. However, digital pathology revealed significant improvements in the degree of collagen fiber reticulation (-12%, p < 0.001). Semaglutide did not affect atherosclerosis relative to controls. Additionally, we compared the transcriptome profile of FFD-fed Ldlr-/-.Leiden mice with a human gene set that differentiates human NASH patients with severe fibrosis from those with mild fibrosis. In FFD-fed Ldlr-/-.Leiden control mice, this gene set was upregulated as well, while semaglutide predominantly reversed this gene expression. Using a translational model with advanced NASH, we demonstrated that semaglutide is a promising candidate with particular potential for the treatment of hepatic steatosis and inflammation, while for the reversal of advanced fibrosis, combinations with other NASH agents may be necessary.
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Affiliation(s)
- José A Inia
- Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
- Cardiology, Leiden University Medical Center (LUMC), 2333 ZA Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center (LUMC), 2300 RC Leiden, The Netherlands
| | - Geurt Stokman
- Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
| | - Martine C Morrison
- Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
| | - Nicole Worms
- Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
| | - Lars Verschuren
- Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
| | - Martien P M Caspers
- Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
| | - Aswin L Menke
- Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
| | | | - Li Chen
- PharmaNest Inc., Princeton, NJ 08540, USA
| | | | - J Wouter Jukema
- Cardiology, Leiden University Medical Center (LUMC), 2333 ZA Leiden, The Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center (LUMC), 2300 RC Leiden, The Netherlands
- Netherlands Heart Institute, 3511 EP Utrecht, The Netherlands
| | - Hans M G Princen
- Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
| | - Anita M van den Hoek
- Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), 2333 BE Leiden, The Netherlands
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Wang S, Li K, Pickholz E, Dobie R, Matchett KP, Henderson NC, Carrico C, Driver I, Jensen MB, Chen L, Petitjean M, Bhattacharya D, Fiel MI, Liu X, Kisseleva T, Alon U, Adler M, Medzhitov R, Friedman SL. An autocrine signaling circuit in hepatic stellate cells underlies advanced fibrosis in nonalcoholic steatohepatitis. Sci Transl Med 2023; 15:eadd3949. [PMID: 36599008 PMCID: PMC10686705 DOI: 10.1126/scitranslmed.add3949] [Citation(s) in RCA: 39] [Impact Index Per Article: 39.0] [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] [Received: 06/09/2022] [Accepted: 11/01/2022] [Indexed: 01/05/2023]
Abstract
Advanced hepatic fibrosis, driven by the activation of hepatic stellate cells (HSCs), affects millions worldwide and is the strongest predictor of mortality in nonalcoholic steatohepatitis (NASH); however, there are no approved antifibrotic therapies. To identify antifibrotic drug targets, we integrated progressive transcriptomic and morphological responses that accompany HSC activation in advanced disease using single-nucleus RNA sequencing and tissue clearing in a robust murine NASH model. In advanced fibrosis, we found that an autocrine HSC signaling circuit emerged that was composed of 68 receptor-ligand interactions conserved between murine and human NASH. These predicted interactions were supported by the parallel appearance of markedly increased direct stellate cell-cell contacts in murine NASH. As proof of principle, pharmacological inhibition of one such autocrine interaction, neurotrophic receptor tyrosine kinase 3-neurotrophin 3, inhibited human HSC activation in culture and reversed advanced murine NASH fibrosis. In summary, we uncovered a repertoire of antifibrotic drug targets underlying advanced fibrosis in vivo. The findings suggest a therapeutic paradigm in which stage-specific therapies could yield enhanced antifibrotic efficacy in patients with advanced hepatic fibrosis.
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Affiliation(s)
- Shuang Wang
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai; New York NY, 10029, USA
| | - Kenneth Li
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai; New York NY, 10029, USA
| | - Eliana Pickholz
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai; New York NY, 10029, USA
| | - Ross Dobie
- Centre for Inflammation Research, The Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, EH16 4TJ, UK
| | - Kylie P. Matchett
- Centre for Inflammation Research, The Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, EH16 4TJ, UK
| | - Neil C. Henderson
- Centre for Inflammation Research, The Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, EH16 4TJ, UK
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH16 4TJ, UK
| | | | - Ian Driver
- Gordian Biotechnology, San Francisco CA, 94107, USA
| | | | - Li Chen
- PharmaNest, Inc, Princeton NJ, 08540, USA
| | | | - Dipankar Bhattacharya
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai; New York NY, 10029, USA
| | - Maria I. Fiel
- Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai; New York NY, 10029, USA
| | - Xiao Liu
- Department of Surgery, University of California, San Diego, La Jolla CA, 92093, USA
| | - Tatiana Kisseleva
- Department of Surgery, University of California, San Diego, La Jolla CA, 92093, USA
| | - Uri Alon
- Department Molecular Cell Biology, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Miri Adler
- Tananbaum Center for Theoretical and Analytical Human Biology, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Ruslan Medzhitov
- Howard Hughes Medical Institute, Department of Immunobiology, Yale University School of Medicine, New Haven CT, 06510, USA
| | - Scott L. Friedman
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai; New York NY, 10029, USA
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6
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Petitjean M, Randoux Y, Jordens A, Saadaoui H, Haemers J. Low-complexity mapping of soil temperature for thermal treatment follow-up. J Contam Hydrol 2022; 250:104056. [PMID: 35933846 DOI: 10.1016/j.jconhyd.2022.104056] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 07/26/2022] [Accepted: 07/27/2022] [Indexed: 06/15/2023]
Abstract
Thermal desorption is a method of soil treatment that heats soil in order to vaporize and extract contaminants. It relies on temperature measurements to assess the progress of the remediation, but these measurements are generally not numerous because of cost constraints. This paper proposes a low-complexity method to interpolate sparse temperature data over the whole site to generate visual representations that ease the treatment follow-up. The temperatures of the points that are not monitored are approximated by a weighted average of the 3 closest measurements, then a third-degree polynomial is fitted to the data via a finite element method. The resulting approximations yield an overall Root Mean Square Error (RMSE) of the temperature estimation of 35 K, which allows for realistic representations of the temperature at each point of the map with reduced sensor deployment.
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Briand F, Maupoint J, Brousseau E, Breyner N, Bouchet M, Costard C, Leste-Lasserre T, Petitjean M, Chen L, Chabrat A, Richard V, Burcelin R, Dubroca C, Sulpice T. Elafibranor improves diet-induced nonalcoholic steatohepatitis associated with heart failure with preserved ejection fraction in Golden Syrian hamsters. Metabolism 2021; 117:154707. [PMID: 33444606 DOI: 10.1016/j.metabol.2021.154707] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/04/2021] [Accepted: 01/07/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND Cardiovascular disease is the leading cause of deaths in nonalcoholic steatohepatitis (NASH) patients. Mouse models, while widely used for drug development, do not fully replicate human NASH nor integrate the associated cardiac dysfunction, i.e. heart failure with preserved ejection fraction (HFpEF). To overcome these limitations, we established a nutritional hamster model developing both NASH and HFpEF. We then evaluated the effects of the dual peroxisome proliferator activated receptor alpha/delta agonist elafibranor developed for the treatment of NASH patients. METHODS Male Golden Syrian hamsters were fed for 10 to 20 weeks with a free choice diet, which presents hamsters with a choice between control chow diet with normal drinking water or a high fat/high cholesterol diet with 10% fructose enriched drinking water. Biochemistry, histology and echocardiography analysis were performed to characterize NASH and HFpEF. Once the model was validated, elafibranor was evaluated at 15 mg/kg/day orally QD for 5 weeks. RESULTS Hamsters fed a free choice diet for up to 20 weeks developed NASH, including hepatocyte ballooning (as confirmed with cytokeratin-18 immunostaining), bridging fibrosis, and a severe diastolic dysfunction with restrictive profile, but preserved ejection fraction. Elafibranor resolved NASH, with significant reduction in ballooning and fibrosis scores, and improved diastolic dysfunction with significant reduction in E/A and E/E' ratios. CONCLUSION Our data demonstrate that the free choice diet induced NASH hamster model replicates the human phenotype and will be useful for validating novel drug candidates for the treatment of NASH and associated HFpEF.
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Affiliation(s)
- François Briand
- Physiogenex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France.
| | - Julie Maupoint
- Cardiomedex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France
| | - Emmanuel Brousseau
- Physiogenex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France
| | - Natalia Breyner
- Physiogenex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France
| | - Mélanie Bouchet
- Physiogenex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France
| | - Clément Costard
- Cardiomedex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France
| | | | - Mathieu Petitjean
- PharmaNest, 100 Overlook Center, FL2, Princeton, NJ 08540, United States of America
| | - Li Chen
- PharmaNest, 100 Overlook Center, FL2, Princeton, NJ 08540, United States of America
| | - Audrey Chabrat
- Sciempath Labo, 7 rue de la Gratiole, 37270 Larcay, France
| | | | - Rémy Burcelin
- Inserm U1048 CHU Rangueil, BP 84225, 31432 Toulouse Cedex 4, France
| | - Caroline Dubroca
- Cardiomedex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France
| | - Thierry Sulpice
- Physiogenex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France; Cardiomedex, 280 rue de l'Hers, ZAC de la Masquère, 31750 Escalquens, France
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Gunduz C, Basoglu OK, Kvamme JA, Verbraecken J, Anttalainen U, Marrone O, Steiropoulos P, Roisman G, Joppa P, Hein H, Trakada G, Hedner J, Grote L, Steiropoulos P, Verbraecken J, Petiet E, Trakada G, Montserrat J, Fietze I, Penzel T, Ondrej L, Rodenstein D, Masa J, Bouloukaki I, Schiza S, Kent B, McNicholas W, Ryan S, Riha R, Kvamme J, Hein H, Schulz R, Grote L, Hedner J, Zou D, Pépin J, Levy P, Bailly S, Lavie L, Lavie P, Basoglu O, Tasbakan M, Varoneckas G, Joppa P, Tkacova R, Staats R, Barbé F, Lombardi C, Parati G, Drummond M, van Zeller M, Bonsignore M, Marrone O, Petitjean M, Roisman G, Pretl M, Vitols A, Dogas Z, Galic T, Pataka A, Anttalainen U, Saaresranta T, Plywaczewski R, Sliwinski P, Bielicki P. Long-term positive airway pressure therapy is associated with reduced total cholesterol levels in patients with obstructive sleep apnea: data from the European Sleep Apnea Database (ESADA). Sleep Med 2020; 75:201-209. [DOI: 10.1016/j.sleep.2020.02.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 02/02/2020] [Accepted: 02/25/2020] [Indexed: 12/18/2022]
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9
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Edouard P, Campo D, Bartet P, Marais L, Petitjean M, Roisman G, Bruyneel M, Escourrou P. 0579 Non Intrusive and Unattended Sleep Analyzer Effectively Screens Patients Suspected of Sleep Apnea: A Comparison With Polysomnography. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Sleep Apnea Syndrome (SAS) is largely underdiagnosed due to the cost and availability of Polysomnography (PSG). We aimed at evaluating the diagnosis of SAS with the WITHINGS Sleep Apnea Detector (SAD), a non-intrusive pressure and sound sensor placed under the mattress.
Methods
118 patients (67 F, 49 years, BMI 33kg/m²) suspected of SAS had an in-laboratory PSG together with Sleep Apnea Detector. From the pressure signal, Sleep Apnea Detector derives respiratory and cardiac signals and movements. From the microphone, snoring and snorting are detected. These features are used to detect sleep periods with a Random Forest classifier and apnea and hypopnea events with a Convolutional Neural Network. The Total Sleep Time (TST) and Apnea Hypopnea Index (AHI) deduced (TSTsad, AHIsad) are compared with the PSG results scored according to AASM rules (TSTpsg, AHIpsg). AHI and TST were compared using bias and Mean Absolute Error (MAE). Sensitivity, specificity, likelihood ratios (LR) and AUROC were calculated for AHI thresholds of 15 and 30/hr.
Results
The average (SD) TSTpsg was 367 (61) minutes. Sleep Apnea Detector overestimated TST by 25 minutes, 7.0% of the average duration in the sample. The precision is acceptable, with a MAE=53 minutes. Average AHIpsg was 32.5 (30.1) and AHIsad 32.8 (29.9). The bias was 0.3 (95% CI [-2.7, 3.3]), MAE=10.3. The sensitivity (Se15) and specificity (Sp15) and their 95% confidence intervals were Se15=88.0% [79.0, 94.1] and Sp15=88.6% [73.3, 96.8]. Positive and negative LR were respectively LR+15=7.70 and LR-15=0.136. AUROC15=0.926. At the 30 threshold, Se30=86.0% [73.3, 94.2] and Sp30=91.2% [81.8, 96.7]. Positive and negative LR were LR+30=9.75 and LR-30=0.153. AUROC30=0.954.
Conclusion
Sleep Apnea Detector has excellent sensitivity and specificity, low bias and good precision. Thus it can be used as an unattended SAS screening device in patients likely to suffer from SAS.
Support
WITHINGS
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Affiliation(s)
- P Edouard
- WITHINGS, issy-les-moulineaux, FRANCE
| | - D Campo
- WITHINGS, issy-les-moulineaux, FRANCE
| | - P Bartet
- WITHINGS, issy-les-moulineaux, FRANCE
| | - L Marais
- WITHINGS, issy-les-moulineaux, FRANCE
| | | | - G Roisman
- Hôpital Antoine-Béclère, Clamart, FRANCE
| | - M Bruyneel
- Hôpital Saint-Pierre, Bruxelles, BELGIUM
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10
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Roth JD, Feigh M, Veidal SS, Fensholdt LKD, Rigbolt KT, Hansen HH, Chen LC, Petitjean M, Friley W, Vrang N, Jelsing J, Young M. INT-767 improves histopathological features in a diet-induced ob/ob mouse model of biopsy-confirmed non-alcoholic steatohepatitis. World J Gastroenterol 2018; 24:195-210. [PMID: 29375205 PMCID: PMC5768938 DOI: 10.3748/wjg.v24.i2.195] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 11/24/2017] [Accepted: 12/04/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To characterize the efficacy of the dual FXR/TGR5 receptor agonist INT-767 upon histological endpoints in a rodent model of diet-induced and biopsy-confirmed non-alcoholic steatohepatitis (NASH).
METHODS The effects of INT-767 on histological features of NASH were assessed in two studies using Lepob/ob (ob/ob) NASH mice fed the AMLN diet (high fat with trans-fat, cholesterol and fructose). In a proof-of-concept study, Lepob/ob (ob/ob) NASH mice were first dosed with INT-767 (3 or 10 mg/kg for 8 wk). A second ob/ob NASH study compared INT-767 (3 and 10 mg/kg) to obeticholic acid (OCA) (10 or 30 mg/kg; 16 wk). Primary histological endpoints included qualitative and quantitative assessments of NASH. Other metabolic and plasma endpoints were also assessed. A comparative assessment of INT-767 and OCA effects on drug distribution and hepatic gene expression was performed in C57Bl/6 mice on standard chow. C57Bl/6 mice were orally dosed with INT-767 or OCA (1-30 mg/kg) for 2 wk, and expression levels of candidate genes were assessed by RNA sequencing and tissue drug levels were measured by liquid chromatography tandem-mass spectrometry.
RESULTS INT-767 dose-dependently (3 and 10 mg/kg, PO, QD, 8 wk) improved qualitative morphometric scores on steatohepatitis severity, inflammatory infiltrates and fibrosis stage. Quantitative morphometric analyses revealed that INT-767 reduced parenchymal collagen area, collagen fiber density, inflammation (assessed by Galectin-3 immunohistochemistry) and hepatocyte lipid droplet area following INT-767 treatment. In a comparative study (16 wk), the FXR agonists OCA (10 and 30 mg/kg) and INT-767 (3 and 10 mg/kg) both improved NASH histopathology, with INT-767 exerting greater therapeutic potency and efficacy than OCA. Mechanistic studies suggest that both drugs accumulate similarly within the liver and ileum, however, the effects of INT-767 may be driven by enhanced hepatic, but not ileal, FXR function.
CONCLUSION These findings confirm the potential utility of FXR and dual FXR/TGR5 activation as disease intervention strategies in NASH.
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MESH Headings
- Animals
- Bile Acids and Salts/metabolism
- Bile Acids and Salts/pharmacology
- Chromatography, High Pressure Liquid
- Diet, High-Fat
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Gene Expression Regulation
- Liver/drug effects
- Liver/metabolism
- Liver/pathology
- Liver Cirrhosis/etiology
- Liver Cirrhosis/metabolism
- Liver Cirrhosis/pathology
- Liver Cirrhosis/prevention & control
- Mice, Inbred C57BL
- Mice, Obese
- Microscopy, Fluorescence, Multiphoton
- Non-alcoholic Fatty Liver Disease/etiology
- Non-alcoholic Fatty Liver Disease/metabolism
- Non-alcoholic Fatty Liver Disease/pathology
- Non-alcoholic Fatty Liver Disease/prevention & control
- Obesity/drug therapy
- Obesity/etiology
- Obesity/metabolism
- Obesity/pathology
- Proof of Concept Study
- Receptors, Cytoplasmic and Nuclear/agonists
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, G-Protein-Coupled/agonists
- Receptors, G-Protein-Coupled/metabolism
- Signal Transduction/drug effects
- Tandem Mass Spectrometry
- Time Factors
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Affiliation(s)
- Jonathan D Roth
- Intercept Pharmaceuticals, Intercept Pharmaceuticals, San Diego, CA 92121, United States
| | | | | | | | | | | | - Li C Chen
- PharmaNest, Genesis Imaging Services, Princeton, NJ 08540, United States
| | - Mathieu Petitjean
- PharmaNest, Genesis Imaging Services, Princeton, NJ 08540, United States
| | - Weslyn Friley
- Qualyst Transporter Solutions, Durham, NC 27713, United States
| | | | | | - Mark Young
- Intercept Pharmaceuticals, Intercept Pharmaceuticals, San Diego, CA 92121, United States
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11
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Deramaudt T, Vinit S, Efthimiadi L, Keomani E, Petitjean M, Bonay M. Evaluation of the Nrf2‐mediated anti‐oxidative and anti‐inflammatory responses in phrenic motoneurons following C2 hemisection in adult rat. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.656.3] [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: 11/11/2022]
Affiliation(s)
| | - S Vinit
- INSERM U1179 Université de VersaillesFrance
| | | | - E Keomani
- INSERM U1179 Université de VersaillesFrance
| | | | - M Bonay
- INSERM U1179 Université de VersaillesFrance
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12
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Vinit S, Petitjean M, Keomani E, Deramaudt T, Bonay M. Early Spinal Cord Rewiring Revealed by Transcranial Magnetic Stimulation following C2 Partial Injury: Implication of the Crossed Phrenic Pathway. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.656.1] [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: 11/11/2022]
Affiliation(s)
- S Vinit
- INSERM U1179 Université de VersaillesFrance
| | | | - E Keomani
- INSERM U1179 Université de VersaillesFrance
| | | | - M Bonay
- INSERM U1179 Université de VersaillesFrance
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13
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Petitjean M, Vinit S, Keomani E, Deramaudt T, Spruance V, Bezdudnaya T, Lane M, Bonay M. Interdisciplinary approaches of transcranial magnetic stimulation applied to a respiratory neuronal circuitry model. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.656.2] [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: 11/11/2022]
Affiliation(s)
| | - S Vinit
- INSERM U1179 Université de VersaillesFrance
| | - E Keomani
- INSERM U1179 Université de VersaillesFrance
| | | | - V Spruance
- College of Medicine Drexel UniversityUnited States
| | - T Bezdudnaya
- College of Medicine Drexel UniversityUnited States
| | - M Lane
- College of Medicine Drexel UniversityUnited States
| | - M Bonay
- INSERM U1179 Université de VersaillesFrance
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14
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Petitjean M, Vinit S, Keomani E, Deramaudt T, Spruance V, Bezdudnaya T, Lane M, Bonay M. Explorations respiratoires et neuroanatomiques des effets de la stimulation magnétique transcrânienne chez le rat. Rev Mal Respir 2015. [DOI: 10.1016/j.rmr.2015.02.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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15
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Vinit S, Djerbal L, Keomani E, Deramaudt T, Petitjean M, Bonay M. Implication de la voie de signalisation Nrf2 dans la neuroplasticité respiratoire en réponse à un traumatisme cervical de la moelle épinière. Rev Mal Respir 2015. [DOI: 10.1016/j.rmr.2015.02.023] [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: 10/23/2022]
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16
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Doridam J, Périn B, Petitjean M, Macron JM, Merle P. Étude de la conduction du nerf ulnaire lors d’une neuropathie par hypersensibilité à la pression : comparaison avec l’atteinte du nerf ulnaire au coude. Rev Neurol (Paris) 2014. [DOI: 10.1016/j.neurol.2014.01.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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17
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Benkaidali L, Andre F, Maouche B, Siregar P, Benyettou M, Maurel F, Petitjean M. Computing cavities, channels, pores and pockets in proteins from non-spherical ligands models. Bioinformatics 2013; 30:792-800. [DOI: 10.1093/bioinformatics/btt644] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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18
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Azabou E, Roche N, Sharshar T, Bussel B, Lofaso F, Petitjean M. P 99. Effects of transcranial direct-current stimulation on diaphragm corticospinal pathway excitability. Clin Neurophysiol 2013. [DOI: 10.1016/j.clinph.2013.04.177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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19
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Boudarham J, Pradon D, Prigent H, Vaugier I, Barbot F, Letilly N, Falaize L, Orlikowski D, Petitjean M, Lofaso F. Optoelectronic Vital Capacity Measurement for Restrictive Diseases. Respir Care 2013; 58:633-8. [DOI: 10.4187/respcare.01916] [Citation(s) in RCA: 8] [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: 11/05/2022]
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20
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Ko J, Petitjean M. P8.5 An age-related change in the ipsilateral silent period of a small hand muscle. Clin Neurophysiol 2011. [DOI: 10.1016/s1388-2457(11)60336-2] [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: 11/16/2022]
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21
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Petitjean M, Crépin JC. PTMS2 Influence of transcranial magnetic stimulation waveforms on the ipsilateral silent period of a small hand muscle. Clin Neurophysiol 2011. [DOI: 10.1016/s1388-2457(11)60655-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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David P, Mora I, Terrien J, Lelard T, Petitjean M. Leg muscles activities during hyperventilation following a cycling exercise. Electromyogr Clin Neurophysiol 2010; 50:39-45. [PMID: 20349557] [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: 05/29/2023]
Abstract
The goal of this study was to establish how increased ventilation modifies postural stability, as characterized by body sway and leg muscle activities. Twelve healthy subjects had to perform six 30-second postural tests: one pre-exercise test while breathing gently and then one test every minute for the five minutes immediately following a maximum-intensity, incremental cycling exercise test. Subjects were asked to maintain an upright stance on a force plate for 30 s, with their eyes open. Movement of the centre of pressure in the sagittal plane was monitored in the time and spectral domains. Myoelectric activities of the soleus and tibialis anterior muscles were recorded using surface electromyography. Ventilatory parameters were measured with a portable, telemetric device. Postural changes related to respiratory variations were quantified by coherence analysis. The results showed that hyperventilation induced by exercise was accompanied by a significant increase in postural parameters, indicating a reduction in postural stability following a change in ventilatory drive. Coherence analysis confirmed the ventilatory origin of the postural oscillations. The results suggest that ventilation may be an important factor in postural disturbance during physical activity. The observed increases in leg muscle activities were most likely related to musculo-articular stiffening.
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Affiliation(s)
- P David
- Université de Picardie Jules Verne, Faculté des Sciences du Sport, Allée Paschal Grousset, 80025 Amiens, Cedex 1, France
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23
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Abstract
The wwLigCSRre web server performs ligand-based screening using a 3D molecular similarity engine. Its aim is to provide an online versatile facility to assist the exploration of the chemical similarity of families of compounds, or to propose some scaffold hopping from a query compound. The service allows the user to screen several chemically diversified focused banks, such as Kinase-, CNS-, GPCR-, Ion-channel-, Antibacterial-, Anticancer- and Analgesic-focused libraries. The server also provides the possibility to screen the DrugBank and DSSTOX/Carcinogenic compounds databases. User banks can also been downloaded. The 3D similarity search combines both geometrical (3D) and physicochemical information. Starting from one 3D ligand molecule as query, the screening of such databases can lead to unraveled compound scaffold as hits or help to optimize previously identified hit molecules in a SAR (Structure activity relationship) project. wwLigCSRre can be accessed at http://bioserv.rpbs.univ-paris-diderot.fr/wwLigCSRre.html.
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Affiliation(s)
- O Sperandio
- MTi, INSERM UMR-S973, Université Paris Diderot - Paris 7, F75013, Paris, France
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24
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Petitjean M, Mirabel P, Calvé SL. Uptake Measurements of Acetaldehyde on Solid Ice Surfaces and on Solid/Liquid Supercooled Mixtures Doped with HNO3in the Temperature Range 203−253 K. J Phys Chem A 2009; 113:5091-8. [DOI: 10.1021/jp810131f] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M. Petitjean
- Laboratoire des Matériaux, Surfaces et Procédés pour la Catalyse (LMSPC, UMR 7515 CNRS/UDS), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
| | - Ph. Mirabel
- Laboratoire des Matériaux, Surfaces et Procédés pour la Catalyse (LMSPC, UMR 7515 CNRS/UDS), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
| | - S. Le Calvé
- Laboratoire des Matériaux, Surfaces et Procédés pour la Catalyse (LMSPC, UMR 7515 CNRS/UDS), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France
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25
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Bauvais C, Barbault F, Zhu Y, Petitjean M, Fan BT. Elucidation of chiral recognition processes of macrocyclic antibiotic vancomycin. SAR QSAR Environ Res 2006; 17:253-64. [PMID: 16815766 DOI: 10.1080/10659360600787783] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
A theoretical investigation was carried out on the retention and separation of enantiomeric molecules including nonsteroidal anti-inflammatory drugs, anti-neoplastic compounds and N-derivatized amino acids by capillary electrophoresis using macrocyclic antibiotics, a new class of chiral selectors, as stationary phase. Firstly docking methods were used to study the enantiorecognition in chiral electrophoresis. The molecular dynamics simulations of the two diastereoisomer complexes were then performed in order to understand how these antibiotics recognize the enantiomers. Another approach was applied in this study to establish a quantitative structure-enantioselectivity relationship (QSER) model, able to describe the resolution of a series of chiral compounds in capillary electrophoresis using vancomycin as the resolving agent.
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Affiliation(s)
- C Bauvais
- ITODYS, CNRS UMR 7086, Université Paris 7 - Denis Diderot, 1 rue Guy de la Brosse, 75005, Paris, France
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26
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Medelli J, Lounana J, Messan F, Menuet JJ, Petitjean M. Testing of pulmonary function in a professional cycling team. J Sports Med Phys Fitness 2006; 46:298-306. [PMID: 16823362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
AIM Asthma affecting elite athletes has been studied mainly in subjects practicing winter sports. The aim of our study was to test the pulmonary function in order to evaluate bronchial hyper-responsiveness prevalence in a team of 25 male professional cyclists (27.9+/-3.9 years old with a VO(2max) equal to 69.9+/-6.6 mL.min(-1) x kg(-1)). METHODS Using a questionnaire that queried the presence or absence of asthma history or common symptoms of exercise induced bronchospasm, 72% of the subjects had upper airway or bronchial symptoms. Using a pneumotachograph, we recorded a forced flow-volume curve at rest, after a maximal exercise test with ambient air, and after beta2-agonist inhalation, then during a methacholine challenge. RESULTS In our study, 52% of the subjects showed clinical symptoms associated with bronchial responsiveness during methacholine test, a proportion which is much higher than the average population (3-20%). However, ERS-ATS pulmonary function testing criteria at rest (reduced FEV1, FEV1/FVC, FEF25-75%) were not fulfilled by any of them. In the asthmatic group, O2max was significantly higher (70.5+/-6 vs 68.6+/-8.2 mL.min-1.kg-1, P<0.05). This remained true for submaximal loads suggesting that ventilation energy cost related to bronchial hyper-responsiveness was also higher. CONCLUSIONS We have reported in this study that professional cyclists have a far higher prevalence of bronchial hyper-responsiveness than the average population, which can be regarded as a real health issue.
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Affiliation(s)
- J Medelli
- Unit of Biology of the Effort and Sports Medicine, University Hospital Center, Amiens, France.
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27
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Maldonado AG, Petitjean M, Doucet JP, Panaye A, Fan BT. MolDIA: XML based system of molecular diversity analysis towards virtual screening and QSPR. SAR QSAR Environ Res 2006; 17:11-23. [PMID: 16513549 DOI: 10.1080/10659360600562038] [Citation(s) in RCA: 2] [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] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In this paper a new chemoinformatics tool for Molecular Diversity Analysis (MolDIA) is introduced. The objective of this system is the analysis of molecular similarity and diversity through the treatment of structural and physicochemical information. Current needs for chemical databases include the analysis, the management and the retrieval of chemical information. The implementation of eXtended Markup Languages (XML) is proposed as a basis for representing and structuring the chemical information contained in data structures and databases. The adequate descriptor vector and related physicochemical properties have been defined and constructed. The benefits of XML in chemoinformatics are discussed, as well as, the applications of this system in a virtual screening environment.
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Affiliation(s)
- A G Maldonado
- ITODYS, University Paris 7 -- Denis Diderot, CNRS UMR-7086, 1, rue Guy de la Brosse, 75005 Paris, France
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28
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Bureau A, Lahet JJ, Lenfant F, Bouyer F, Petitjean M, Chaillot B, Freysz M. Optimization of a model of red blood cells for the study of anti-oxidant drugs, in terms of concentration of oxidant and phosphate buffer. Biomed Pharmacother 2005; 59:341-4. [PMID: 16039823 DOI: 10.1016/j.biopha.2005.06.002] [Citation(s) in RCA: 3] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Indexed: 11/19/2022] Open
Abstract
The aggression of erythrocytes by an oxidative stress induces hemolysis. This paper aims to valid a model of erythrocytes in terms of composition of the phosphate buffer solution and of concentration of a well-known oxidant, AAPH. Three compositions of phosphate buffer solution are mixed with three concentrations of oxidant. The influence of these two parameters on hemolysis is independently studied by a variance analysis and a Kruskal-Wallis test when ANOVA is not available. The hemolysis rate increases with time at fixed oxidant concentration, but is not influenced by the composition of the buffer solution. The highest hemolysis rate, 90%, was only measured within 2 h with the highest oxidant concentration. If we retain this concentration of oxidant, the lower concentration of the buffer can by eliminated by a significant less hemolysis and the highest concentration of the buffer can by chosen in regard of the better precision for a similar hemolysis compared to the mean buffer. We hope to study the effect of anti-oxidant agent with such a model of erythrocytes.
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Affiliation(s)
- A Bureau
- Laboratoire de Chimie Bio-Inorganique, Faculté de Pharmacie de Dijon, 7, boulevard Jeanne-d'Arc, 21079 Dijon, France.
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Barone R, Petitjean M, Baralotto C, Piras P, Chanon M. Information theory description of synthetic strategies. A new similarity index. J PHYS ORG CHEM 2002. [DOI: 10.1002/poc.556] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
When isolated muscle synchronous contraction is evoked during in vitro twitches, mechanical vibrations at the surface of the muscle reflect resonant behavior. In contrast, voluntary contraction corresponds to the asynchronous contraction of recruited motor units, therefore, this kind of excitation could lead to different muscle vibrational behavior. We have studied human biceps brachii muscle during voluntary contraction in 10 healthy subjects. Low and high levels of voluntary contraction were explored with simultaneous recording of surface vibration by two sensors located longitudinally or perpendicular to the muscle's main axis. Cross-correlation and coherence functions were computed. Coherence functions revealed a common vibration frequency band between 17 and 28 Hz. Cross correlation functions revealed in-phase vibration for longitudinal sensors and opposite phase vibration for perpendicular sensors thus confirming a lateral bending movement. This behavior suggests that the acoustic myogram is the response of the muscle as a global resonant structure to the local fluctuations of pressure.
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Affiliation(s)
- M Ouamer
- Laboratoire de Physique Biomédicale, Université René Descartes, Paris, France
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32
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Cordier C, Marcourt L, Petitjean M, Dodin G. Conformational variation of the central CG site in d(ATGACGTCAT)2 and d(GAAAACGTTTTC)2. An NMR, molecular modelling and 3D-homology investigation. Eur J Biochem 1999; 261:722-33. [PMID: 10215889 DOI: 10.1046/j.1432-1327.1999.00314.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The determination of the solution structure of two self-complementary oligomers d(ATGACGTCAT)2 (CG10) and d(GAAAACGTTTTC)2 (CG12), both containing the 5'-pur-ACGT-pyr-3' sequence, is reported. The impact of the base context on the conformation of the central CpG site has been examined by a combined approach of: (a) 2D 1H-NMR and 31P-NMR; (b) molecular mechanics under experimental constraints; (c) back-calculations of NOESY spectra and iterative refinements of distances; and (d) 3D-homology search of the central tetrad ACGT within the complete oligonucleotides. A full NMR study of each fragment is achieved by means of standard 2D experiments: NOESY, 2D homonuclear Hartmann-Hahn spectroscopy, double-quantum-filtered COSY and heteronuclear 1H-31P correlation. Sugar phase angle, epsilon-zeta difference angle and NOE-derived distances are input as experimental constraints to generate molecular models by energy minimization with the help of jumna. The morass program is used to iteratively refine the structures obtained. The similarity of the two ACGTs within the whole oligonucleotides is investigated. Both the decamer and the dodecamer adopt a B-like DNA conformation. However, the helical parameters within this conformational type are significantly different in CG12 and CG10. The central CpG step conformation is not locked by its nearest environment (5'A and 3'T) as seen from the structural analysis of ACGT in the two molecules. In CG12, despite the presence of runs of A-T pairs, CpG presents a high twist of 43 degrees and a sugar phase at the guanine of about 180 degrees, previously observed in other ACGT-containing-oligomers. Conversely, ACGT in CG10 exhibits strong inclinations, positive rolls, a flat profile of sugar phase, twist and glycosidic angles, as a result of the nucleotide sequence extending beyond the tetrad. The structural specificity of CG10 and its flexibility (as reflected by its energy) are tentatively related to the process of recognition of the cyclic AMP response element by its cognate protein.
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Affiliation(s)
- C Cordier
- Institut de Topologie et de Dynamique des Systèmes, associé au CNRS, Université D. Diderot (Paris 7), France
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33
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Abstract
Iron uptake by bovine lactoferrin from nitrilotriacetatoFe(III) [FeN(Ac)3] in the presence of bicarbonate has been investigated at pH 7.1-8.7. Deprotonated apolactoferrin interacting with bicarbonate or carbonate extracts iron from nitrilotriacetatoFe(III); the direct second-order rate constant k1 = (4.90 +/- 0.20)x10(4) M(-1) s(-1), a reverse second-order rate constant k(-1) = (1.80+/-0.05)x10(5) M(-1) s(-1), and the iron-exchange equilibrium constant K1 = 0.25+/-0.05. The newly formed iron-protein complex loses a single proton with proton dissociation constant K3a = (17+/-0.5) nM, then undergoes a modification in its conformation followed by the loss of two or three protons; the first-order rate constant k2 = (1.0+/-0.10) s(-1). This induces a new modification in the conformation; the first-order rate constant k3 = (8.75+/-0.40)x10(-3) s(-1). This second modification in conformation controls the rate of iron uptake by the N site of the protein and is followed by a single proton loss; K5a = 8.0 nM. Finally, the holoprotein or the monoferric lactoferrin in their final equilibrated states are produced by a third modification in the conformation occurring in about 9000 s. The mechanism of iron uptake by lactoferrin is very similar to that of serum transferrin with a cooperativity between the C and N sites upon iron uptake but with lower rates, higher affinities and at least one more proton loss involved. These differences may be the result of slight discrepancies in the intimate structures of binding sites for serum transferrin and lactoferrin. In order to analyse the cooperativity between these iron-binding sites, the three-dimensional position of the chain of amino acid residues separating the N and C lobes of human apo-, holo- and dicopper-lactoferrin have been compared by the recognition of the three-dimensional shape dissimilarity program. The interlobe peptides of human hololactoferrin and apolactoferrin showed only 75.5 % tridimensional similarity, indicating that iron uptake affects the three-dimensional structure of the interlobe chain.
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Affiliation(s)
- R Pakdaman
- Institut de Topologie et de Dynamique des Systèmes de l'Université Denis Diderot, Paris, France
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Petitjean M, Maton B, Fourment A. Summation of elementary phonomyograms during isometric twitches in humans. Eur J Appl Physiol Occup Physiol 1998; 77:527-35. [PMID: 9650738 DOI: 10.1007/s004210050371] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
To study its summation principle, the phonomyogram (PMG) from the first interosseus dorsalis muscle was recorded in five subjects during single twitches evoked by electrical stimulation over the motor point. By increasing the current pulse from threshold to maximal intensity, PMG amplitude increased linearly with motor unit recruitment. The twitch amplitude-intensity relationship was also linear. The PMG amplitude was therefore linearly related to the external force. For all these relationships highly significant correlation coefficients were found. These relationships were interpreted as being a consequence of an orderly recruitment, although, contrary to what happens during voluntary contraction, the largest and strongest motor units were recruited before the smallest and weakest ones during axon electrical stimulation. The PMG onset always preceded twitch onsets as indicated by latency measurements [mean 3.2 (SD 1.3) ms versus 11.5 (SD 3.9) ms, respectively]. Moreover, PMG and twitch latencies may have been significantly reduced by recruitment, suggesting that orderly recruitment influenced both PMG amplitude and occurrence. These results were interpreted as being the result of the summation of elementary PMG from every contracting motor unit and the stiffness change of the muscle medium occurring with recruitment.
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Affiliation(s)
- M Petitjean
- Laboratoire de Physiologie du Mouvement, Université Paris-Sud ERS Centre National de la Recherche Scientifique 102, Orsay, France
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Abstract
The time-frequency characteristics of muscular sounds (phonomyogram) produced by the contraction of the human diaphragm under various contractile states is evaluated with the cone-kernel distribution. The results show that the instantaneous frequency of the phonomyogram of the diaphragm has a high cross-correlation (an average of 0.91 +/- 0.06) with the transdiaphragmatic pressure, with a delay varying between 25 and 35 ms. The instantaneous frequency response of the phonomyogram of the diaphragm shows a behaviour similar to that of the frog muscle; it rapidly rises and then fades out. However, the maximum of the instantaneous frequency of the phonomyogram of the diaphragm is not proportional to the maximum of the transdiaphragmatic pressure. This analysis also demonstrates the usefulness of the cone-kernel distribution for studying frequency-modulated signals like the muscular sound signals.
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Affiliation(s)
- D Chen
- Laboratoire de Génie Biomédical, Institut de Recherches Cliniques de Montréal, Université de Montréal, Québec, Canada
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36
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Abstract
Diaphragmatic phonomyogram (PMG) evoked by maximal bilateral phrenic nerve stimulation has previously been described as a good index of contractility of fresh and fatigued diaphragm. In the present study we hypothesized that diaphragmatic contractility changes could be even more simply evaluated by recording the relationship between the PMG and the compound motor action potential (CMAP) amplitudes during graded submaximal unilateral phrenic nerve stimulation at various intensities. Relationships between CMAPs and PMGs from left and right hemidiaphragms were recorded by means of surface electrodes and miniature microphones placed over the lower rib cage (eighth intercostal space) in five healthy subjects before and after a diaphragmatic fatigue task. These relationships in each subject were linear. The slope of these relationships decreased by 61.1 +/- 20.7% and by 70.4 +/- 14.6% on the right and left side respectively, but the intercepts did not change significantly. By comparison, transdiaphragmatic twitch pressure during maximal bilateral stimulation (PdiT) declined by 49.4 +/- 15%. We conclude that PMG during submaximal unilateral phrenic nerve stimulation is a reliable index of diaphragm contractility changes caused by fatigue. Using this method we have shown that all diaphragmatic motor units can be affected by fatigue.
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Affiliation(s)
- M Petitjean
- Département d'Anesthésie-réanimation, Hôtel-Dieu de Montréal, Université de Montréal, Québec, Canada
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Abstract
BACKGROUND A diaphragmatic phonomyogram (PMG) evoked by maximal phrenic nerve stimulation at end expiratory lung volume (FRC) has been previously described as a good index of changes in diaphragmatic contractility with fatigue. A study was undertaken to assess whether this conclusion could be extended to different lung volumes. METHODS Diaphragmatic compound motor action potentials (CMAPs) were recorded on each side of the chest by the means of surface electrodes placed over the eight intercostal spaces in five healthy subjects. Diaphragmatic PMGs from both sides were recorded with condenser microphones fixed to the skin close to the CMAP recording electrodes. Oesophageal and gastric balloon tipped catheters were employed to measure transdiaphragmatic pressure twitches (TwPDI) which served as the standard measure of changes in diaphragmatic contractility. PMG and TwPDI responses were compared at different lung volumes over inspiratory capacity both before and after fatiguing inspiratory resistive loading. RESULTS No consistent relationship was found in different subjects or on different days in the same subject between PMG and lung volume or between PMG and TwPDI. However, the PMG:CMAP ratio from both sides at any given lung volume decreased after fatigue in roughly the same proportion as the TwPDI. CONCLUSIONS These results show that, although PMG can detect changes in diaphragmatic contractility caused by fatigue in normal subjects, lung volume changes need to be controlled and each subject should serve as his or her own control.
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Affiliation(s)
- M Petitjean
- Département d'Anesthésie, Université de Montréal, Québec, Canada
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38
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Abstract
The insertional action of the abdominal muscles was studied in supine anesthetized, apneic rabbits and dogs by comparing the changes in esophageal pressure (Pes), upper and lower rib cage circumference (Cru,u and Crc,I) and lung volume (VL) in response to electrical stimulation of all abdominal muscles before and after evisceration. In eviscerated animals, abdominal muscle contraction increased Pes and decreased both VL and Cre,I, but had no effect on Crc,u. Maximal responses were obtained at submaximal intensities of stimulation, and became larger with increasing lung volume. Relative to the vital capacity in intact animals, maximal delta VL for stimulation performed at FRC and TLC were 7.2 +/- 2.9(SD) and 39.5 +/- 7% in rabbits, and 6.3 +/- 0.8 and 18.3 +/- 5.9% in dogs, respectively. Relative to the changes in lung volume occurring with maximal contraction of the abdominal muscles in intact animals, the values of delta VL observed in the eviscerated animals amounted to approximately 35 and approximately 45% for stimulation performed at FRC and TLC, respectively. Hence, abdominal muscles exert substantial insertional action on the lower rib cage that can result in appreciable lung deflationary effects, particularly at elevated lung volumes.
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Affiliation(s)
- E D'Angelo
- Istituto di Fisiologia Umana I, Università di Milano, Italy
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39
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Abstract
The purpose of this study was to determine the characteristics of the specific phonomyogram (PMG) of active motor units activated during voluntary isometric contractions. The electromyogram (EMG) and PMG were recorded from 87 anconeus motor units in 14 subjects. The elementary PMG from single motor units was analysed with a spike-triggered averaging technique. The electro-acoustical delay was 3.5 (SD 1.1) ms, which is within the range of values reported in the literature for PMG evoked by motor nerve stimulation. All motor units demonstrated a pattern of impulsive sounds with a duration of 87.2 (SD 10.7) ms. These results would imply that PMG is linked to the contractile activity of the motor units. These results also would suggest that PMG recorded from a contracting muscle in situ reflects the summation of elementary PMG during voluntary contraction more than the overall mechanical properties of the muscle.
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Affiliation(s)
- M Petitjean
- Laboratoire de Physiologie du Mouvement, Université Paris-Sud ERS CNRS 102, Orsay, France
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40
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Abstract
As previously demonstrated in humans, contracting skeletal muscles vibrate laterally and generate sound. The amplitude of this acoustic signal, called the phonomyogram (PMG), is related to muscle force production. As in limb muscles, the diaphragm might produce mechanical tissue vibrations and a PMG. We recorded diaphragm twitches during phrenic nerve stimulation in normal subjects at FRC. Diaphragmatic compound motor action potentials (CMAP) were recorded on each side of the chest by surface electrodes over the eighth intercostal space. Condenser microphones were fixed to the skin close to the electrodes, and esophageal and gastric balloons employed to measure transdiaphragmatic pressure (Pdi). For unilateral and bilateral supramaximal single shocks (0.1 ms), PMG onset latencies from either side (12.4 +/- 0.6 ms) were intermediate between those of CMAP (7.3 +/- 0.7 ms) and of Pdi (20.3 +/- 2.8 ms). By varying stimulation intensity, significant linear relationships were obtained between CMAP and PMG amplitudes on each side. A significant linear relationship was also found between PMG for each side and Pdi peak values. PMG and Pdi both decreased with fatigue of the diaphragm. We conclude that PMG in response to single phrenic nerve shocks is a noninvasive index of electromechanical coupling, recruitment, and transdiaphragmatic pressure generation by the diaphragm.
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Affiliation(s)
- M Petitjean
- Meakins-Christie Laboratories, Royal Victoria Hospital, McGill University Clinic, Montreal, Quebec, Canada
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41
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Abstract
Phonomyogram (PMG, or acoustic myogram) is known to increase with force in isometric contractions. We investigated this relationship for dynamic contractions against different inertias. PMG and surface electromyogram (EMG) from biceps brachii and brachioradialis muscles were simultaneously recorded with the angular acceleration of elbow flexions. These were self-initiated movements (30 degrees) toward a fixed target and performed against two different inertias. PMG and EMG were integrated from the onset of the signal to the end of the acceleration phase. Phono- and electromechanical delays were also measured. For integrated EMG (iEMG), there was a linear relationship between integrated PMG (iPMG) and force, the slope of which did not depend on inertia. There was also a linear relationship between iPMG or iEMG and angular acceleration, with a higher slope for the highest inertia condition. There was also a family of linear relationships between iPMG or iEMG and angular acceleration, and their slopes depended on inertia. Measurements of the phono- and electromechanical delays showed that onset of PMG followed that of EMG but preceded onset of acceleration. It is suggested that PMG expresses tension of the underlying muscle contractile elements. Given the simplicity of the PMG method, we conclude that PMG allows convenient evaluation of muscle tension during human dynamic contraction.
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Affiliation(s)
- M Petitjean
- Laboratoire de Physiologie de la Motricité, Centre Hospitalier Universitaire Pitié-Salpêtrière, Paris, France
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Abstract
Acute osteoporosis after spinal cord injury is related to an early increase in osteoclastic resorption. Healthy subjects subjected to bed rest similarly increase their osteoclast number in trabecular bone. Bisphosphonates possess a highly antiosteoclastic activity. The effects of a 120 day bed rest period, with or without etidronate therapy on cortical bone were measured in 15 subjects. Cortical thickness and cortical porosity were measured on transiliac bone biopsies taken before and after the bed rest period. Osteoclasts were detected histochemically and were counted with a semiautomatic image analyzer. Cortical thickness, cortical porosity, and cortical osteoclast number were not significantly modified in subjects submitted to bed rest alone. In the etidronate-treated patients, cortical bone mass parameters were also found to be unaffected, but the most striking feature was that the osteoclast number was unchanged. Trabecular osteoclasts, on the contrary, were increased in the untreated subjects (+95.2%) but decreased in the treated subjects (-78%). Bone cells may have heterogeneous responses according to their trabecular or cortical location. Cortical osteoclasts seem to be unaffected by etidronate therapy.
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Affiliation(s)
- D Chappard
- LBTO-Laboratoire de Biologie du Tissu Osseux, Faculté de Médecine, Saint Etienne, France
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Chappard D, Plantard B, Petitjean M, Alexandre C, Riffat G. Alcoholic cirrhosis and osteoporosis in men: a light and scanning electron microscopy study. J Stud Alcohol 1991; 52:269-74. [PMID: 2046377 DOI: 10.15288/jsa.1991.52.269] [Citation(s) in RCA: 46] [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: 12/30/2022]
Abstract
Subjects with chronic alcoholism are associated with a higher prevalence of bone fractures, compared with age-matched controls. However, the pathogenesis of alcoholic osteopathy remains poorly understood. In this study, the bone cells activities and the bone matrix were studied using different techniques such as bone morphometry, scanning electron microscopy and computer reconstruction. Male patients (N = 20), aged 59.1 +/- 10.1 years, presenting a chronic decompensated alcoholic cirrhosis, were admitted into this study. A histomorphometric analysis of a transiliac bone biopsy was done after a double tetracycline labeling of the bone. A scanning electron microscopy (SEM) study was performed on eight out of the 20 patients on an additional biopsy. The bone mass was significantly decreased in cirrhotic patients. A marked defect in the osteoblastic function was observed with reduced osteoid parameters, lower mean wall thickness, and slower bone formation rate leading to a thinning of bone trabeculae. Conversely, trabecular resorption surfaces were markedly increased. SEM examination of bone biopsies was also consistent with delayed and impaired osteoblastic activity leading to extended and scalloped resorption surfaces covered by unusually thin layers of calcified collagen fibers. The reduced osteoblastic activity associated with normal osteoclastic function appears to play a major role in the pathogenesis of alcoholic osteoporosis leading to decreased bone mass with thinner trabeculae.
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Affiliation(s)
- D Chappard
- Laboratoire de Biologié du Tissue Osseux (LBTO), Faculté de Médecine, Saint Etienne, France
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44
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O'Daniel TG, Petitjean M, Jones SC, Zogg J, Martinez SA, Nolph MB, Schultz GS. Epidermal growth factor binding and action on tympanic membranes. Ann Otol Rhinol Laryngol 1990; 99:80-4. [PMID: 2294837 DOI: 10.1177/000348949009900114] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A significant percentage of tympanic membrane (TM) perforations require some form of therapy to heal. Topical application of epidermal growth factor (EGF), a potent mitogen for epidermal and mesodermal cells, promotes healing of injuries in tissues histologically similar to TM, such as cornea and skin. We evaluated TM as a target tissue for EGF action. Specific, high affinity receptors for EGF were detected in TM (Kd = 3.1 nM, 150 fmol receptor/mg protein). Autoradiography of iodine 125-EGF binding to intact TMs revealed that EGF receptors were present on cells in the stratified squamous epithelial layer and in the stromal/mucoepithelial layer. Repetitive treatment of perforated cat TMs with 20 micrograms of EGF formulated in saline induced substantial hyperplasia of epithelial and stromal layers compared to paired TMs treated with saline. A single treatment of perforated cat TMs with 50 micrograms of EGF formulated in a hydrogel or in shredded Gelfoam produced significantly (p less than .05) smaller perforations at 6 days following the operation compared to paired TMs treated with vehicles. These results demonstrate that TM is a target tissue for EGF and that topical treatment with EGF stimulates healing of TM perforations.
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Affiliation(s)
- T G O'Daniel
- Department of Surgery, University of Louisville, Kentucky
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45
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Maton B, Petitjean M, Cnockaert JC. Phonomyogram and electromyogram relationships with isometric force reinvestigated in man. Eur J Appl Physiol Occup Physiol 1990; 60:194-201. [PMID: 2347322 DOI: 10.1007/bf00839159] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Contracting muscle generates sounds which can be recorded easily by means of a microphone. To determine if a phomomyogram (PMG) can be used to monitor muscle force, a comparison was made between simultaneous recordings of PMG and monopolar electromyogram (EMG) from the isometrically contracting biceps brachii muscle and the external flexion force. Locations of the monopolar electrode and microphone were identified in relation to the motor point. Whatever the recording site, PMG amplitude was proportional to EMG amplitude and both showed a quadratic relationship to muscle force. Changes in the PMG spectrum with force were similar to those in EMG, i.e. the mean power frequency increased up to about 30% maximal voluntary contraction and then reached a plateau. Despite a slightly higher variability, PMG was shown to be a valid index of muscular isometric force. At the same force, the amplitude of both PMG and EMG was lower in the prone than in the supine position of the hand. This result indicated a selective recording of biceps brachii muscle activity.
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Affiliation(s)
- B Maton
- Laboratoire de Physiologie de la Motricité, URA CNRS 385, CHU Pitié-Salpétrière, Paris, France
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46
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Hammade H, Petitjean M, Douaire M, Mallard J, Mèrat P. [Not Available]. Genet Sel Evol (1983) 1987; 19:249-266. [PMID: 22879283 PMCID: PMC2713282 DOI: 10.1186/1297-9686-19-2-249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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Petitjean M, Servouse M. Comparative study of some characteristics of the semen of RR (rose comb) or rr (single comb) cockerels. Reprod Nutr Dev (1980) 1981; 21:1085-93. [PMID: 6218547 DOI: 10.1051/rnd:19810807] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Comparative studies were made of semen samples from subfertile RR and normally fertile rr cockerels. These samples were obtained either by abdominal massage or directly from the tip of papillae. The numbers of collected sperm did not differ between genotypes and the sperm from RR cockerels were less motile than those from rr cockerels irrespective of the semen collection method. The uric acid concentration of seminal plasma was influenced by the semen collection method (massage greater than papillae) but no variations were induced by the genotypes. The ATP-ase and acid phosphatase activities found in the seminal plasma were influenced respectively by the genotype (rr greater than RR) and the semen collection method (papillae greater than massage). The fumarase and acrosin activities found in the sperm were not influenced by the semen collection methods while acrosin activity was found to be higher in RR than in rr cockerels. Correlations between these various characteristics are given in detail.
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Poignant JC, Gressier H, Petitjean M, Regnier G, Canevari R. A new central direct dopaminergic stimulant: 1-(Coumaran-5-yl methyl)-4-(2-thiazolyl) piperazine hydrochloride (S 3608). Experientia 1975; 31:1204-5. [PMID: 1243126 DOI: 10.1007/bf02326795] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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49
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Petitjean M. [Biological control of harmful mollusks. Review of the main results according to recent principal works]. Annee Biol 1966; 5:271-295. [PMID: 5956136] [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: 05/21/2023]
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50
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Prettre M, Imelik B, Blanchin L, Petitjean M. Zum Bildungsmechanismus adsorbierender und katalytisch wirksamer Aluminiumoxyde. Angew Chem Int Ed Engl 1953. [DOI: 10.1002/ange.19530652202] [Citation(s) in RCA: 41] [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: 11/10/2022]
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