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Liao A, Cavigliasso F, Savary L, Kawecki TJ. Effects of an entomopathogenic fungus on the reproductive potential of Drosophila males. Ecol Evol 2024; 14:e11242. [PMID: 38590549 PMCID: PMC10999951 DOI: 10.1002/ece3.11242] [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: 11/17/2023] [Revised: 03/20/2024] [Accepted: 03/25/2024] [Indexed: 04/10/2024] Open
Abstract
While mortality is often the primary focus of pathogen virulence, non-lethal consequences, particularly for male reproductive fitness, are less understood; however, they are essential for understanding how sexual selection contributes to promoting resistance. We investigated how the fungal pathogen Metarhizium brunneum affects mating ability, fertility, and seminal fluid protein (SFP) expression of male Drosophila melanogaster paired with highly receptive virgin females in non-competitive settings. Depending on sex and dose, there was a 3-6-day incubation period after infection, followed by an abrupt onset of mortality. Meanwhile, the immune response was strongly induced already 38 h after infection and continued to increase as infection progressed. Latency to mate somewhat increased during the incubation period compared to sham-treated males, but even on Day 5 post infection >90% of infected males mated within 2 h. During the incubation period, M. brunneum infection reduced male reproductive potential (the number of offspring sired without mate limitation) by 11%, with no clear increase over time. Approaching the end of the incubation period, infected males had lower ability to convert number of mating opportunities into number of offspring. After repeated mating, infected males had lower SFP expression than sham controls, more so in males that mated with few mates 24 h earlier. Overall, despite strong activation of the immune response, males' mating ability and fertility remained surprisingly little affected by the fungal infection, even shortly before the onset of mortality. This suggests that the selection for resistance acts mainly through mortality, and the scope for fertility selection to enhance resistance in non-competing settings is rather limited.
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Affiliation(s)
- Aijuan Liao
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
| | - Fanny Cavigliasso
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
| | - Loriane Savary
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
| | - Tadeusz J. Kawecki
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
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Cavigliasso F, Savitsky M, Koval A, Erkosar B, Savary L, Gallart-Ayala H, Ivanisevic J, Katanaev VL, Kawecki TJ. Cis-regulatory polymorphism at fiz ecdysone oxidase contributes to polygenic evolutionary response to malnutrition in Drosophila. PLoS Genet 2024; 20:e1011204. [PMID: 38452112 PMCID: PMC10962836 DOI: 10.1371/journal.pgen.1011204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 03/25/2024] [Accepted: 02/29/2024] [Indexed: 03/09/2024] Open
Abstract
We investigate the contribution of a candidate gene, fiz (fezzik), to complex polygenic adaptation to juvenile malnutrition in Drosophila melanogaster. Experimental populations maintained for >250 generations of experimental evolution to a nutritionally poor larval diet (Selected populations) evolved several-fold lower fiz expression compared to unselected Control populations. Here we show that this divergence in fiz expression is mediated by a cis-regulatory polymorphism. This polymorphism, originally sampled from a natural population in Switzerland, is distinct from a second cis-regulatory SNP previously identified in non-African D. melanogaster populations, implying that two independent cis-regulatory variants promoting high fiz expression segregate in non-African populations. Enzymatic analyses of Fiz protein expressed in E. coli demonstrate that it has ecdysone oxidase activity acting on both ecdysone and 20-hydroxyecdysone. Four of five fiz paralogs annotated to ecdysteroid metabolism also show reduced expression in Selected larvae, implying that malnutrition-driven selection favored general downregulation of ecdysone oxidases. Finally, as an independent test of the role of fiz in poor diet adaptation, we show that fiz knockdown by RNAi results in faster larval growth on the poor diet, but at the cost of greatly reduced survival. These results imply that downregulation of fiz in Selected populations was favored by selection on the nutritionally poor diet because of its role in suppressing growth in response to nutrient shortage. However, they suggest that fiz downregulation is only adaptive in combination with other changes evolved by Selected populations, which ensure that the organism can sustain the faster growth promoted by fiz downregulation.
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Affiliation(s)
- Fanny Cavigliasso
- Department of Ecology and Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Mikhail Savitsky
- HumanaFly Facility, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Alexey Koval
- Translational Research Centre in Oncohaematology, Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Berra Erkosar
- Department of Ecology and Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Loriane Savary
- Department of Ecology and Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Hector Gallart-Ayala
- Metabolomics Unit, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Julijana Ivanisevic
- Metabolomics Unit, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Vladimir L. Katanaev
- Translational Research Centre in Oncohaematology, Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Tadeusz J. Kawecki
- Department of Ecology and Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
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Erkosar B, Dupuis C, Cavigliasso F, Savary L, Kremmer L, Gallart-Ayala H, Ivanisevic J, Kawecki TJ. Evolutionary adaptation to juvenile malnutrition impacts adult metabolism and impairs adult fitness in Drosophila. eLife 2023; 12:e92465. [PMID: 37847744 PMCID: PMC10637773 DOI: 10.7554/elife.92465] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 10/12/2023] [Indexed: 10/19/2023] Open
Abstract
Juvenile undernutrition has lasting effects on adult metabolism of the affected individuals, but it is unclear how adult physiology is shaped over evolutionary time by natural selection driven by juvenile undernutrition. We combined RNAseq, targeted metabolomics, and genomics to study the consequences of evolution under juvenile undernutrition for metabolism of reproductively active adult females of Drosophila melanogaster. Compared to Control populations maintained on standard diet, Selected populations maintained for over 230 generations on a nutrient-poor larval diet evolved major changes in adult gene expression and metabolite abundance, in particular affecting amino acid and purine metabolism. The evolved differences in adult gene expression and metabolite abundance between Selected and Control populations were positively correlated with the corresponding differences previously reported for Selected versus Control larvae. This implies that genetic variants affect both stages similarly. Even when well fed, the metabolic profile of Selected flies resembled that of flies subject to starvation. Finally, Selected flies had lower reproductive output than Controls even when both were raised under the conditions under which the Selected populations evolved. These results imply that evolutionary adaptation to juvenile undernutrition has large pleiotropic consequences for adult metabolism, and that they are costly rather than adaptive for adult fitness. Thus, juvenile and adult metabolism do not appear to evolve independently from each other even in a holometabolous species where the two life stages are separated by a complete metamorphosis.
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Affiliation(s)
- Berra Erkosar
- Department of Ecology and Evolution, University of LausanneLausanneSwitzerland
| | - Cindy Dupuis
- Department of Ecology and Evolution, University of LausanneLausanneSwitzerland
| | - Fanny Cavigliasso
- Department of Ecology and Evolution, University of LausanneLausanneSwitzerland
| | - Loriane Savary
- Department of Ecology and Evolution, University of LausanneLausanneSwitzerland
| | - Laurent Kremmer
- Department of Ecology and Evolution, University of LausanneLausanneSwitzerland
| | - Hector Gallart-Ayala
- Metabolomics Unit, Faculty of Biology and Medicine, University of LausanneLausanneSwitzerland
| | - Julijana Ivanisevic
- Metabolomics Unit, Faculty of Biology and Medicine, University of LausanneLausanneSwitzerland
| | - Tadeusz J Kawecki
- Department of Ecology and Evolution, University of LausanneLausanneSwitzerland
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Cavigliasso F, Savary L, Spangenberg JE, Gallart-Ayala H, Ivanisevic J, Kawecki TJ. Experimental evolution of metabolism under nutrient restriction: enhanced amino acid catabolism and a key role of branched-chain amino acids. Evol Lett 2023; 7:273-284. [PMID: 37475747 PMCID: PMC10355184 DOI: 10.1093/evlett/qrad018] [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: 02/06/2023] [Revised: 04/04/2023] [Accepted: 04/24/2023] [Indexed: 07/22/2023] Open
Abstract
Periodic food shortage is a common ecological stressor for animals, likely to drive physiological and metabolic adaptations to alleviate its consequences, particularly for juveniles that have no option but to continue to grow and develop despite undernutrition. Here we study changes in metabolism associated with adaptation to nutrient shortage, evolved by replicate Drosophila melanogaster populations maintained on a nutrient-poor larval diet for over 240 generations. In a factorial metabolomics experiment we showed that both phenotypic plasticity and genetically-based adaptation to the poor diet involved wide-ranging changes in metabolite abundance; however, the plastic response did not predict the evolutionary change. Compared to nonadapted larvae exposed to the poor diet for the first time, the adapted larvae showed lower levels of multiple free amino acids in their tissues-and yet they grew faster. By quantifying accumulation of the nitrogen stable isotope 15N we show that adaptation to the poor diet led to an increased use of amino acids for energy generation. This apparent "waste" of scarce amino acids likely results from the trade-off between acquisition of dietary amino acids and carbohydrates observed in these populations. The three branched-chain amino acids (leucine, isoleucine, and valine) showed a unique pattern of depletion in adapted larvae raised on the poor diet. A diet supplementation experiment demonstrated that these amino acids are limiting for growth on the poor diet, suggesting that their low levels resulted from their expeditious use for protein synthesis. These results demonstrate that selection driven by nutrient shortage not only promotes improved acquisition of limiting nutrients, but also has wide-ranging effects on how the nutrients are used. They also show that the abundance of free amino acids in the tissues does not, in general, reflect the nutritional condition and growth potential of an animal.
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Affiliation(s)
- Fanny Cavigliasso
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Loriane Savary
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Jorge E Spangenberg
- Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, Switzerland
| | - Hector Gallart-Ayala
- Metabolomics Unit, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Julijana Ivanisevic
- Metabolomics Unit, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Tadeusz J Kawecki
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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Maroni A, Savary L, Deho A, Tanase A, Dossier C, Dauger S, Poncelet G. Malignant arterial hypertension in a 2-month-old girl: Etiological diagnosis and treatment. Arch Pediatr 2022; 29:537-539. [DOI: 10.1016/j.arcped.2022.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 05/20/2022] [Accepted: 06/18/2022] [Indexed: 11/28/2022]
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Savary L, De Luca A, El Arid JM, Ma I, Soule N, Garnier E, Neville P, Chantepie A, Maakaroun Z, Lefort B. Systematic skin and nasal decolonization lowers Staphylococcus infection in pediatric cardiac surgery. Arch Pediatr 2022; 29:177-182. [PMID: 35094904 DOI: 10.1016/j.arcped.2022.01.009] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 11/29/2021] [Accepted: 01/13/2022] [Indexed: 10/19/2022]
Abstract
BACKGROUND Postoperative infections occur in approximately 10% of pediatric cardiac surgeries, involving Staphylococcus species in most cases. Nasal decontamination of Staphylococcus with mupirocin has been reported to reduce postoperative Staphylococcus infections after cardiac surgery in adults, but the effect of preoperative decontamination in children undergoing cardiac surgery has not been sufficiently studied to reach consensus. METHODS We conducted a single-center retrospective study to evaluate the impact of systematic preoperative decolonization with intranasal mupirocin application and skin-washing with chlorhexidine soap on postoperative Staphylococcus infection in children undergoing cardiac surgery. Our population was divided into three groups according to decolonization protocol (group N: no decolonization; group T: targeted decolonization in Staphylococcus aureus [SA] carriers only; and group S: systematic decolonization). RESULTS A total of 393 children were included between October 2011 and August 2015 (122 in group N, 148 in group T, and 123 in group S). The Staphylococcus infection rate significantly decreased in group S compared to group N (0.8% vs. 7.7%; p < 0.05) and tended to decrease in group S compared to group T (0.8% vs. 4.7%; p = 0.06). Systematic decontamination also significantly reduced the rate of infections starting from the skin (including surgical site infections and bloodstream infections) compared to targeted decolonization or lack of decolonization, but had no effect on the rate of pulmonary infections. CONCLUSION The results of our study suggest that systematic preoperative skin and nasal decontamination, regardless of SA carriage status, could reduce the rate of postoperative Staphylococcus infections after cardiac surgery in children.
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Affiliation(s)
- L Savary
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France; Université François Rabelais, Tours, France
| | - A De Luca
- Université François Rabelais, Tours, France; Nutrition Pédiatrique - Unité Mobile de Nutrition, CHRU Tours, France; INSERM UMR 1069 "Nutrition, Croissance et Cancer", Tours, France
| | - J-M El Arid
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France
| | - I Ma
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France; Université François Rabelais, Tours, France
| | - N Soule
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France
| | - E Garnier
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France
| | - P Neville
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France
| | - A Chantepie
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France; Université François Rabelais, Tours, France
| | - Z Maakaroun
- Médecine interne et Maladies Infectieuses, CHRU Tours, France
| | - B Lefort
- Institut des Cardiopathies Congénitales de Tours, CHRU Tours, France; Université François Rabelais, Tours, France; INSERM UMR 1069 "Nutrition, Croissance et Cancer", Tours, France.
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7
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Cavigliasso F, Dupuis C, Savary L, Spangenberg JE, Kawecki TJ. Experimental evolution of post-ingestive nutritional compensation in response to a nutrient-poor diet. Proc Biol Sci 2020; 287:20202684. [PMID: 33259760 PMCID: PMC7739944 DOI: 10.1098/rspb.2020.2684] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The geometric framework of nutrition predicts that populations restricted to a single imbalanced diet should evolve post-ingestive nutritional compensation mechanisms bringing the blend of assimilated nutrients closer to physiological optimum. The evolution of such nutritional compensation is thought to be mainly driven by the ratios of major nutrients rather than overall nutritional content of the diet. We report experimental evolution of divergence in post-ingestive nutritional compensation in populations of Drosophila melanogaster adapted to diets that contained identical imbalanced nutrient ratios but differed in total nutrient concentration. Larvae from 'Selected' populations maintained for over 200 generations on a nutrient-poor diet with a 1 : 13.5 protein : carbohydrate ratio showed enhanced assimilation of nitrogen from yeasts and reduced assimilation of carbon from sucrose than 'Control' populations evolved on a diet with the same nutrient ratio but fourfold greater nutrient concentration. Compared to the Controls, the Selected larvae also accumulated less triglycerides relative to protein. This implies that the Selected populations evolved a higher assimilation rate of amino acids from the poor imbalanced diet and a lower assimilation of carbohydrates than Controls. Thus, the evolution of nutritional compensation may be driven by changes in total nutrient abundance, even if the ratios of different nutrients remain unchanged.
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Affiliation(s)
- Fanny Cavigliasso
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Cindy Dupuis
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Loriane Savary
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Jorge E Spangenberg
- Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, Switzerland
| | - Tadeusz J Kawecki
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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Suzuki T, Savary L, Liu JP, Lynn JW, Balents L, Checkelsky JG. Singular angular magnetoresistance in a magnetic nodal semimetal. Science 2019; 365:377-381. [DOI: 10.1126/science.aat0348] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 06/07/2019] [Indexed: 11/02/2022]
Affiliation(s)
- T. Suzuki
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - L. Savary
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA
- Université de Lyon, École Normale Supérieure de Lyon, Université Claude Bernard Lyon I, CNRS, Laboratoire de Physique, 46 Allée d’Italie, 69007 Lyon, France
| | - J.-P. Liu
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA
- Department of Physics, The Hong Kong University of Science and Technology, Kowloon, Hong Kong
| | - J. W. Lynn
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - L. Balents
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA
| | - J. G. Checkelsky
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Croft AP, Campos J, Jansen K, Turner JD, Marshall J, Attar M, Savary L, Wehmeyer C, Naylor AJ, Kemble S, Begum J, Dürholz K, Perlman H, Barone F, McGettrick HM, Fearon DT, Wei K, Raychaudhuri S, Korsunsky I, Brenner MB, Coles M, Sansom SN, Filer A, Buckley CD. Distinct fibroblast subsets drive inflammation and damage in arthritis. Nature 2019; 570:246-251. [PMID: 31142839 PMCID: PMC6690841 DOI: 10.1038/s41586-019-1263-7] [Citation(s) in RCA: 482] [Impact Index Per Article: 96.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 05/02/2019] [Indexed: 01/18/2023]
Abstract
The identification of lymphocyte subsets with non-overlapping effector functions has been pivotal to the development of targeted therapies in immune-mediated inflammatory diseases (IMIDs)1,2. However, it remains unclear whether fibroblast subclasses with non-overlapping functions also exist and are responsible for the wide variety of tissue-driven processes observed in IMIDs, such as inflammation and damage3-5. Here we identify and describe the biology of distinct subsets of fibroblasts responsible for mediating either inflammation or tissue damage in arthritis. We show that deletion of fibroblast activation protein-α (FAPα)+ fibroblasts suppressed both inflammation and bone erosions in mouse models of resolving and persistent arthritis. Single-cell transcriptional analysis identified two distinct fibroblast subsets within the FAPα+ population: FAPα+THY1+ immune effector fibroblasts located in the synovial sub-lining, and FAPα+THY1- destructive fibroblasts restricted to the synovial lining layer. When adoptively transferred into the joint, FAPα+THY1- fibroblasts selectively mediate bone and cartilage damage with little effect on inflammation, whereas transfer of FAPα+ THY1+ fibroblasts resulted in a more severe and persistent inflammatory arthritis, with minimal effect on bone and cartilage. Our findings describing anatomically discrete, functionally distinct fibroblast subsets with non-overlapping functions have important implications for cell-based therapies aimed at modulating inflammation and tissue damage.
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Affiliation(s)
- Adam P Croft
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- Versus Arthritis Centre of Excellence in the Pathogenesis of Rheumatoid Arthritis, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Joana Campos
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Kathrin Jansen
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
| | - Jason D Turner
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Jennifer Marshall
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Moustafa Attar
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
| | - Loriane Savary
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Corinna Wehmeyer
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- Musculoskeletal Medicine, University of Muenster, Muenster, Germany
| | - Amy J Naylor
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Samuel Kemble
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Jenefa Begum
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Kerstin Dürholz
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nürnberg (FAU) and Universitätsklinikum Erlangen, Erlangen, Germany
| | - Harris Perlman
- Department of Medicine, Division of Rheumatology, Northwestern University, Feinberg School of Medicine Chicago, Evanston, IL, USA
| | - Francesca Barone
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Helen M McGettrick
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | | | - Kevin Wei
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Soumya Raychaudhuri
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ilya Korsunsky
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael B Brenner
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Mark Coles
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
| | - Stephen N Sansom
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
| | - Andrew Filer
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- Versus Arthritis Centre of Excellence in the Pathogenesis of Rheumatoid Arthritis, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
- University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- MRC and Versus Arthritis Centre for Musculoskeletal Ageing Research (CMAR), College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK
| | - Christopher D Buckley
- Rheumatology Research Group, Institute for Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK.
- Versus Arthritis Centre of Excellence in the Pathogenesis of Rheumatoid Arthritis, College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK.
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK.
- MRC and Versus Arthritis Centre for Musculoskeletal Ageing Research (CMAR), College of Medical and Dental Sciences, University of Birmingham, Queen Elizabeth Hospital, Birmingham, UK.
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Gendreau H, Lagarce L, Savary L, Urban T, Hureaux J. Toxicité immunologique sévère du nivolumab et réponse tumorale prolongée dans le cancer bronchique non à petites cellules. Rev Mal Respir 2018. [DOI: 10.1016/j.rmr.2018.05.004] [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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Daturi M, Borel MM, Leclaire A, Savary L, Costentin G, Lavalley JC, Raveau B. Crystallographic and catalytic studies of a new solid solution CdMoxW1–xO4. ACTA ACUST UNITED AC 2017. [DOI: 10.1051/jcp/1996932043] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Gadelorge M, Bourdens M, Bardiaux C, Espagnolle N, Murrell J, Savary L, Ribaud S, Chaput B, Sensebé L. Expansion of Adipose Derived Stromal Cells from Stromal Vascular Fraction in a Single-Use Bioreactor: Proof of Concept in the Mobius® 3L. Cytotherapy 2016. [DOI: 10.1016/j.jcyt.2016.03.267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lefebvre L, Noyon E, Georgescu D, Proust V, Alexandru C, Leheurteur M, Thery JC, Savary L, Rigal O, Di Fiore F, Veyret C, Clatot F. Port catheter versus peripherally inserted central catheter for postoperative chemotherapy in early breast cancer: a retrospective analysis of 448 patients. Support Care Cancer 2015; 24:1397-403. [DOI: 10.1007/s00520-015-2901-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 08/09/2015] [Indexed: 10/23/2022]
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Buissink C, Thompson J, Voet M, Sanderud A, Kamping L, Savary L, Mughal M, Rocha C, Hart G, Parreiral R, Martin G, Hogg P. The influence of experience and training in a group of novice observers: A jackknife alternative free-response receiver operating characteristic analysis. Radiography (Lond) 2014. [DOI: 10.1016/j.radi.2014.06.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lefebvre L, Noyon E, Georgescu D, Alexandru C, Leheurteur M, Thery J, Savary L, Veyret C, Clatot F. Port Catheter Versus Peripherally Inserted Central Catheter in Post-Operative Chemotherapy for Early Breast Cancer: a Retrospective Analysis. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu327.57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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16
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Jeanfaivre T, Gourdier A, Hureaux J, Savary L, Le Guen Y, Blin V, Régnard O, Jousset Y, Picquet J, Mège M, Tuchais C, Caron C, Urban T. 222 Apport de l’imagerie par résonance magnétique cérébrale (IRMc) à la recherche de métastases dans le cadre du bilan d’extension des tumeurs pulmonaires opérables après une tomodensitométrie cérébrale (TDMc) normale. Rev Mal Respir 2007. [DOI: 10.1016/s0761-8425(07)72598-6] [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: 10/22/2022]
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17
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Abstract
Pemetrexed has recently been approved for use in combination with cisplatin as first-line chemotherapy for malignant pleural mesothelioma (MPM). Radiation therapy is frequently administered to the thoracic orifices and no data are available about the interactions between radiotherapy and pemetrexed. We report the first case of radiation recall dermatitis occurring after pemetrexed chemotherapy in a patient with MPM previously treated with radiation therapy to the thoracoscopy and drainage orifices. The patient received chemotherapy with pemetrexed and cisplatin 19 days after completion of chest wall radiation therapy delivering 21 gray in 3 days. Conventional premedication by folic acid and intramuscular administration of Vitamin B12 and prednisolone was correctly performed. Twelve days later, confluent erythematous and pruritus rash of the irradiated skin was observed. The toxicity grade of this lesion was evaluated at 2 according to the Acute Radiation Morbidity Scoring Criteria proposed by the Radiation Therapy Oncology Group. Pemetrexed challenge was performed without worsening of skin lesions. Three weeks later, skin cicatrisation was observed after a desquamative phase. Persistent hyperpigmentation was seen in the irradiated skin. Pemetrexed could also act as a radiosensitizing agent that should be used with care for several weeks after radiotherapy.
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Affiliation(s)
- J Hureaux
- Département de Pneumologie, Centre Hospitalier et Universitaire, 4, rue Larrey, 49 933 Angers Cedex 9, France.
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18
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Eap CB, Bondolfi G, Zullino D, Bryois C, Fuciec M, Savary L, Jonzier-Perey M, Baumann P. Pharmacokinetic Drug Interaction Potential of Risperidone With Cytochrome P450 Isozymes as Assessed by the Dextromethorphan, the Caffeine, and the Mephenytoin Test. Ther Drug Monit 2001; 23:228-31. [PMID: 11360030 DOI: 10.1097/00007691-200106000-00008] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [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: 11/26/2022]
Abstract
Two published case reports showed that addition of risperidone (1 and 2 mg/d) to a clozapine treatment resulted in a strong increase of clozapine plasma levels. As clozapine is metabolized by cytochrome P450 isozymes, a study was initiated to assess the in vivo interaction potential of risperidone on various cytochrome P450 isozymes. Eight patients were phenotyped with dextromethorphan (CYP2D6), mephenytoin (CYP2C19), and caffeine (CYP1A2) before and after the introduction of risperidone. Before risperidone, all eight patients were phenotyped as being extensive metabolizers of CYP2D6 and CYP2C19. Risperidone at dosages between 2 and 6 mg/d does not appear to significantly inhibit CYP1A2 and CYP2C19 in vivo (median plasma paraxanthine/caffeine ratios before and after risperidone: 0.65, 0.69; p = 0.89; median urinary (S)/(R) mephenytoin ratios before and after risperidone:0.11, 0.12; p = 0.75). Although dextromethorphan metabolic ratio is significantly increased by risperidone (median urinary dextromethorphan/dextrorphan ratios before and after risperidone: 0.010, 0.018; p = 0.042), risperidone can be considered a weak in vivo CYP2D6 inhibitor, as this increase is modest and none of the eight patients was changed from an extensive to a poor metabolizer. The reported increase of clozapine concentrations by risperidone can therefore not be explained by an inhibition of CYP1A2, CYP2D6, CYP2C19 or by any combination of the three.
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Affiliation(s)
- C B Eap
- Unit of Biochemistry and Clinical Psychopharmacology, University Department of Adult Psychiatry, Cery Hospital, CH-Prilly-Lausanne, Switzerland.
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Ryndin Y, Candy J, Didillon B, Savary L, Basset J. Surface Organometallic Chemistry on Metals Applied to the Environment: Hydrogenolysis of AsPh3 with Nickel Supported on Alumina. J Catal 2001. [DOI: 10.1006/jcat.2000.3116] [Citation(s) in RCA: 15] [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: 11/22/2022]
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Eap CB, Bouchoux G, Amey M, Cochard N, Savary L, Baumann P. Simultaneous determination of human plasma levels of citalopram, paroxetine, sertraline, and their metabolites by gas chromatography-mass spectrometry. J Chromatogr Sci 1998; 36:365-71. [PMID: 9679303 DOI: 10.1093/chromsci/36.7.365] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A gas chromatography-mass spectrometry method is presented which allows the simultaneous determination of the plasma concentrations of the selective serotonin reuptake inhibitors citalopram, paroxetine, sertraline, and their pharmacologically active N-demethylated metabolites (desmethylcitalopram, didesmethylcitalopram, and desmethylsertraline) after derivatization with the reagent N-methyl-bis(trifluoroacetamide). No interferences from endogenous compounds are observed following the extraction of plasma samples from six different human subjects. The standard curves are linear over a working range of 10-500 ng/mL for citalopram, 10-300 ng/mL for desmethylcitalopram, 5-60 ng/mL for didesmethylcitalopram, 20-400 ng/mL for sertraline and desmethylsertraline, and 10-200 ng/mL for paroxetine. Recoveries measured at three concentrations range from 81 to 118% for the tertiary amines (citalopram and the internal standard methylmaprotiline), 73 to 95% for the secondary amines (desmethylcitalopram, paroxetine and sertraline), and 39 to 66% for the primary amines (didesmethylcitalopram and desmethylsertraline). Intra- and interday coefficients of variation determined at three concentrations range from 3 to 11% for citalopram and its metabolites, 4 to 15% for paroxetine, and 5 to 13% for sertraline and desmethylsertraline. The limits of quantitation of the method are 2 ng/mL for citalopram and paroxetine, 1 ng/mL for sertraline, and 0.5 ng/mL for desmethylcitalopram, didesmethylcitalopram, and desmethylsertraline. No interferences are noted from 20 other psychotropic drugs. This sensitive and specific method can be used for single-dose pharmacokinetics. It is also useful for therapeutic drug monitoring of these three drugs and could possibly be adapted for the quantitation of the two other selective serotonin reuptake inhibitors on the market, namely fluoxetine and fluvoxamine.
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Affiliation(s)
- C B Eap
- Département Universitaire de Psychiatrie Adulte, Hôpital de Cery, Prilly-Lausanne, Switzerland.
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Eap CB, Schnyder C, Besson J, Savary L, Buclin T. Inhibition of CYP2E1 by chlormethiazole as measured by chlorzoxazone pharmacokinetics in patients with alcoholism and in healthy volunteers. Clin Pharmacol Ther 1998; 64:52-7. [PMID: 9695719 DOI: 10.1016/s0009-9236(98)90022-4] [Citation(s) in RCA: 25] [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: 02/08/2023]
Abstract
BACKGROUND Chlormethiazole has been shown in in vitro studies, with use of rat and human liver microsomes, to specifically inhibit cytochrome P4502E1 (CYP2E1)-mediated activity by inhibition of the rate of CYP2E1 gene transcription. It is known that CYP2E1 is involved in the activation of many low-molecular-weight toxins and carcinogens and may be involved in the development of alcohol-induced liver disease. METHODS The pharmacokinetics of a single oral dose of 250 mg chlorzoxazone, a marker of the activity of CYP2E1, were measured in five healthy drug-free volunteers and in 16 patients with alcoholism receiving 1.2 gm or 2.4 gm chlormethiazole per day for 1, 2, or 3 days. The patients were starting an alcohol-withdrawal program and were supposed to have an induced CYP2E1 activity. RESULTS The results suggest that chlormethiazole strongly decreased chlorzoxazone clearance in the patients with alcoholism compared with clearance in the control subjects (3.98 +/- 1.8 L/hr versus 12.7 +/- 5.6 L/hr; p < 0.005), prolonged the elimination half-life (3.91 +/- 1.23 hours versus 1.12 +/- 0.34 hours; p < 0.001), and caused a threefold increase in the area under the concentration versus time curve of chlorzoxazone (73.0 +/- 35.5 mg.hr/L versus 21.3 +/- 13.7 mg.hr/L; p < 0.005). They also suggest that chlormethiazole significantly decreased the area under the concentration versus time curve of the metabolite 6-hydroxy-chlorzoxazone (4.56 +/- 1.27 mg.hr/L versus 7.1 +/- 1.84 mg.hr/L; p < 0.05). CONCLUSION Chlormethiazole administration seems to result in a marked reduction of CYP2E1 activity in subjects with high CYP2E1 activity and could at least partially explain the claimed hepatoprotective action of this drug.
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Affiliation(s)
- C B Eap
- Département Universitaire de Psychiatrie Adulte, Hôpital de Cery, Prilly, Lausanne, Switzerland.
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Eap CB, Schnyder C, Savary L. Determination of chlorzoxazone and 6-hydroxychlorzoxazone in plasma by gas chromatography--mass spectrometry. J Chromatogr B Biomed Sci Appl 1998; 705:139-44. [PMID: 9498681 DOI: 10.1016/s0378-4347(97)00501-x] [Citation(s) in RCA: 9] [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: 02/06/2023]
Abstract
A gas chromatographic-mass spectrometric method is presented which allows the determination of chlorzoxazone and 6-hydroxychlorzoxazone after derivatization with the reagent N-tert.-butyldimethylsilyl-N-methyltrifluoroacetamide. No interference was observed from endogenous compounds following the extraction of plasma samples from six different human subjects. The standard curves were linear over a working range of 20 to 4000 ng/ml and of 20 to 1000 ng/ml for chlorzoxazone and 6-hydroxychlorzoxazone, respectively. Recoveries ranged from 65 to 97% for the two compounds and intra- and inter-day coefficients of variation were always less than 9%. The limit of quantitation of the method was found to be 5 ng/ml for the two compounds, hence allowing its use for single low dose pharmacokinetics.
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Affiliation(s)
- C B Eap
- Département Universitaire de Psychiatrie Adulte, Hôpital de Cery, Prilly-Lausanne, Switzerland
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Jeanfaivre T, Savary L, Richard C. [Benign clear cell tumor ("sugar tumor"). An unusual cause of intrapulmonary coin lesion]. Rev Mal Respir 1997; 14:223-4. [PMID: 9411601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The authors report a case of a 25 years old woman in whom a coin lesion was fortuitously discovered. Initial investigations were negative and an exploratory thoracotomy was performed which enabled a benign clear cell tumour of the lung to be found (sugar tumour). This rare benign tumour whose cellular origin remains indeterminate is in general discovered in a fortuitous manner after a chest x-ray has been performed showing a round peripheral opacity. The diagnosis is confirmed following the excision of the tumour, complementary examinations are not helpful.
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Affiliation(s)
- T Jeanfaivre
- Service de Pneumologie, Centre Hospitalier et Universitaire d'Angers
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Savary L, Saussey J, Costentin G, Bettahar M, Gubelmann-Bonneau M, Lavalley J. Propane oxydehydrogenation reaction on a VPO/TiO2 catalyst. Role of the nature of acid sites determined by dynamic in-situ IR studies. Catal Today 1996. [DOI: 10.1016/s0920-5861(96)00090-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Savary L, Saussey J, Costentin G, Bettahar MM, Lavalley JC, Gubelmann-Bonneau M. Role of the nature of the acid sites in the oxydehydrogenation of propane on a VPO/TiO2 catalyst. An in situ FT-IR spectroscopy investigation. Catal Letters 1996. [DOI: 10.1007/bf00806568] [Citation(s) in RCA: 8] [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: 11/24/2022]
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Abstract
A case of volar dislocation involving the four ulnar metacarpals treated by open reduction and fixation with Kirschner wires is reported. A review of the literature leads the authors to suggest several pathogenic hypotheses. The mechanism may be direct or indirect according to whether the trauma is sustained on the metacarpal heads or on the bases of the metacarpals. Emergency treatment by open reduction and fixation usually provides excellent results.
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Besson A, Flury J, Freeman J, Lehnherr J, Savary L. [The Cardiac Arrest Team of the Vaud University Hospital]. Schweiz Med Wochenschr 1984; 114:830-8. [PMID: 6740301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A resuscitation team has been organized in the CHUV for the purpose of immediate intervention on the scene of cardiac arrest or any other life-threatening condition. The team composition is as follows: 1 anesthesiologist, 1 internist (usually cardiologist) and 1 surgeon. The team is responsible for elaborate resuscitation of in-patients from the general wards as well as out-patients coming for examination or for diagnostic and medicotechnical procedures. The team was almost never called from the intensive care units, from the operating theatres or from the emergency ward. Organization of the CHUV in this respect includes (a) grouping the facilities in larger areas where an alarm is signalled both optically and acoustically, (b) a special priority paging system with pocket radio-receptors (beeps) which can reach all members of the team within seconds, and (c) standardized resuscitation carts strategically located in the hospital. During a period of 7 months the team's work was judged satisfactory. It is called in once every 3 days on average.
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Abstract
The effects of eight antiparkinsonian anticholinergic drugs on motor activity in mice were studied. Trihexyphenidyl, biperiden, benztropine, etybenztropine, procyclidine and tropacine clearly stimulated motor activity. Orphenadrine did not change motor activity, and profenamine had sedative properties. The classification of these drugs by order of their effect on this animal model does not agree with the classification proposed by Deniker et al (1980).
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Cauchoix J, Bloch-Michel H, Benoist M, Deburge A, Chassaing V, Savary L. [Arthrotic sciatica caused by radicular compression of osteophytic origin in the lateral recess. Apropos of 18 cases]. Rev Rhum Mal Osteoartic 1976; 43:475-80. [PMID: 981929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The authors report 18 cases of arthrosic sciatica due to toot compression in the lateral recess by posterior corporeal and/or posterior apophyseal osteophytosis. The authors study the clinical and radiological characteristics that may indicate the diagnosis and discuss the different mechanisms by which vertebral arthrosis can lead to radicular compression. When surgery is necessary because of the persistent nature of the sciatica, a broader approach should be undertaken than that required for excision of the disc, in order to explore fully the roots, the multiplicity of possible compression sites being one of the essential characteristics of these cases of arthrosic radiculopathy. Study of the literature and of the series of sciatica patients operated upon by the authors shows that although discal hernia is far from being the most frequent cause of common sciatica, arthrosic compression is a cause that cannot be ignored, especially in aged subjects.
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