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Dive into the research topics where R. Chiron is active.

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Featured researches published by R. Chiron.


Journal of Cystic Fibrosis | 2011

Safety, efficacy and convenience of tobramycin inhalation powder in cystic fibrosis patients: The EAGER trial

Michael W. Konstan; Patrick A. Flume; Matthias Kappler; R. Chiron; Mark Higgins; Florian Brockhaus; Jie Zhang; G. Angyalosi; Ellie He; David E. Geller

BACKGROUNDnA light-porous-particle, dry-powder formulation of tobramycin was developed, using PulmoSphere® technology, to improve airway delivery efficiency, substantially reduce delivery time, and improve patient convenience and satisfaction. We evaluated the safety, efficacy and convenience of tobramycin inhalation powder (TIP™) versus tobramycin inhalation solution (TIS, TOBI®) for treating Pseudomonas aeruginosa infection in cystic fibrosis (CF) patients aged ≥6 years.nnnMETHODSnIn this open-label study, 553 patients were randomized 3:2 to TIP (total 112mg tobramycin) via the Novartis T-326 Inhaler or TIS 300mg/5mL via PARI LC® PLUS nebulizer twice daily for three treatment cycles (28 days on-drug, 28 days off-drug). Safety, efficacy, and treatment satisfaction outcomes were evaluated.nnnRESULTSnTIP was generally well-tolerated; adverse events were similar in both groups. The rate of cough suspected to be study drug related was higher in TIP-treated patients (TIP: 25.3%; TIS: 4.3%), as was the overall discontinuation rate (TIP: 26.9%; TIS: 18.2%). Increases in FEV(1)% predicted from baseline to Day 28 of Cycle 3 were similar between groups; the mean reduction in sputum P. aeruginosa density (log(10) CFU/g) on Day 28 of Cycle 3 was also comparable between groups. Administration time was significantly less for TIP (mean: 5.6 versus 19.7min, p<0.0001). Treatment satisfaction was significantly higher for TIP for effectiveness, convenience, and global satisfaction.nnnCONCLUSIONSnTIP has a safety and efficacy profile comparable with TIS, and offers a far more convenient treatment option for pseudomonas lung infection in CF.


Chest | 2013

A Proof-of-Concept, Randomized, Controlled Trial of Omalizumab in Patients With Severe, Difficult-to-Control, Nonatopic Asthma

Gilles Garcia; A. Magnan; R. Chiron; Cécile Contin-Bordes; Patrick Berger; Camille Taillé; Gilles Devouassoux; Frédéric de Blay; Louis-Jean Couderc; A. Didier; Dermot S. O'Callaghan; Pierre-Olivier Girodet; Isabelle Bourdeix; Vincent Le Gros; Marc Humbert

BACKGROUNDnWhile up to 50% of patients with severe asthma have no evidence of allergy, IgE has been linked to asthma, irrespective of atopic status. Omalizumab, an anti-IgE monoclonal antibody, is reported to significantly benefit a subset of patients with severe, persistent, allergic asthma. Therefore, we investigated whether omalizumab has biologic and clinical effects in patients with refractory nonatopic asthma.nnnMETHODSnForty-one adult patients who, despite daily treatment with or without maintenance oral corticosteroids, had severe, nonatopic, refractory asthma according to GINA (Global Initiative for Asthma) step 4, were randomized to receive omalizumab or placebo in a 1:1 ratio. The primary end point was the change in expression of high-affinity IgE receptor (FcεRI) on blood basophils and plasmacytoid dendritic cells (pDC2) after 16 weeks. The impact of omalizumab on lung function and clinical variables was also examined.nnnRESULTSnCompared with placebo, omalizumab resulted in a statistically significant reduction in FcεRI expression on basophils and pDC2 (P < .001). The omalizumab group also showed an overall increase in FEV1 compared with baseline (+250 mL, P = .032; +9.9%, P = .029). A trend toward improvement in global evaluation of treatment effectiveness and asthma exacerbation rate was also observed.nnnCONCLUSIONSnOmalizumab negatively regulates FcεRI expression in patients with severe nonatopic asthma, as it does in severe atopic asthma. Omalizumab may have a therapeutic role in severe nonatopic asthma. Nonetheless, our preliminary findings support further investigation to better assess the clinical efficacy of omalizumab.nnnTRIAL REGISTRYnClinicalTrials.gov; No.: NCT01007149; URL: www.clinicaltrials.gov and European Clinical Trials Database, EudraCT; No.: 2009-010937-38; URL: https://www.clinicaltrialsregister.eu.


Journal of Cystic Fibrosis | 2013

Inhaled aztreonam lysine vs. inhaled tobramycin in cystic fibrosis: A comparative efficacy trial

Baroukh M. Assael; Tacjana Pressler; Diana Bilton; Michael Fayon; Rainald Fischer; R. Chiron; Mario LaRosa; Christiane Knoop; Noel G. McElvaney; Sandra A. Lewis; M. Bresnik; A. Bruce Montgomery; Christopher M. Oermann

BACKGROUNDnOpen-label, parallel-group, international trial comparing aztreonam for inhalation solution (AZLI) and tobramycin nebulizer solution (TNS) for cystic fibrosis patients with airway Pseudomonas aeruginosa.nnnMETHODSn273 patients (≥ 6 years); randomized to three 28-day courses (AZLI 75 mg [three-times/day] or TNS 300 mg [twice/day]); 28 off-days separated each course.nnnRESULTSn268 patients were treated (AZLI/TNS: 136/132). Mean baseline FEV1 was 52% predicted. Mean relative changes after 1 course (AZLI: 8.35%; TNS: 0.55%; p<0.001) and mean actual changes across 3 courses (AZLI: 2.05%; TNS: -0.66%; p=0.002) indicated AZLI statistical superiority vs. TNS. AZLI-treated patients had fewer respiratory hospitalizations (p=0.044) and respiratory events requiring additional antipseudomonal antibiotics (p=0.004); both treatments were well tolerated. 133 patients received 1 to 3 courses of AZLI treatment in the open-label extension-period (28-day courses separated by 28 days off-treatment); lung function improvements were comparable regardless of whether patients had received TNS or AZLI in the preceding comparative period.nnnCONCLUSIONSnAZLI demonstrated statistical superiority in lung function and a reduction in acute pulmonary exacerbations compared to TNS over 3 treatment courses (ClinicalTrials.gov: NCT00757237).


American Journal of Physiology-lung Cellular and Molecular Physiology | 2009

LXA4 stimulates ZO-1 expression and transepithelial electrical resistance in human airway epithelial (16HBE14o-) cells

Y. Grumbach; Nga. Vuthi Quynh; R. Chiron; V. Urbach

Lipoxin A(4) (LXA(4)) is a biologically active eicosanoid produced in human airways that displays anti-inflammatory properties. In cystic fibrosis and severe asthma, LXA(4) production has been reported to be decreased, and, in such diseases, one of the consequences of airway inflammation is disruption of the tight junctions. In the present study, we investigated the possible role of LXA(4) on tight junction formation, using transepithelial electrical resistance (TER) measurements, Western blotting, and immunofluorescence. We observed that exposure to LXA(4) (100 nM) for 2 days significantly increased zonula occludens-1 (ZO-1), claudin-1, and occludin expression at the plasma membrane of confluent human bronchial epithelial 16HBE14o- cells. LXA(4) (100 nM) stimulated the daily increase of the 16HBE14o- cell monolayer TER, and this effect was inhibited by boc-2 (LXA(4) receptor antagonist). LXA(4) also had a rapid effect on ZO-1 immunofluorescence at the plasma membrane and increased TER within 10 min. In conclusion, our experiments provide evidence that LXA(4) plays certainly a new role for the regulation of tight junction formation and stimulation of the localization and expression of ZO-1 at the plasma membrane through a mechanism involving the LXA(4) receptor.


Journal of Cystic Fibrosis | 2015

Comparing Mycobacterium massiliense and Mycobacterium abscessus lung infections in cystic fibrosis patients

Anne-Laure Roux; Emilie Catherinot; Nathalie Soismier; Beate Heym; Gil Bellis; L. Lemonnier; R. Chiron; Brigitte Fauroux; Muriel Le Bourgeois; Anne Munck; Isabelle Pin; Isabelle Sermet; Cristina Gutierrez; Nicolas Veziris; Vincent Jarlier; Emmanuelle Cambau; Jean-Louis Herrmann; Didier Guillemot; Jean-Louis Gaillard

BACKGROUNDnMycobacterium massiliense is closely related to Mycobacterium abscessus and is also a frequent cause of mycobacterial lung disease in patients with cystic fibrosis (CF). There has been no previous investigation of possible differences between M. massiliense and M. abscessus infections in the setting of CF.nnnMETHODSnWe studied a prospective cohort of 16 M. massiliense and 27 M. abscessus lung infection cases with CF, with a mean follow-up of 6 years.nnnRESULTSnM. massiliense cases were younger than M. abscessus cases (mean age: 12.8 vs 17.1 years; p=0.02) at the time of the first mycobacterial isolation and also had lower body mass index values (mean: 16.4 vs 19.3 kg/m(2), p=0.002). All M. massiliense cases, except one, had negative BMI Z-score values at the time of the first mycobacterial isolation (11/12 vs 16/23 M. abscessus cases, p=0.04). Clarithromycin-based combination therapies led to mycobacterial eradication in 100% of M. massiliense cases but only in 27% of M. abscessus cases (p=0.009).nnnCONCLUSIONnOur data show a particular link between M. massiliense and malnutrition specifically in CF patients. Unlike M. abscessus, the bacteriological response of M. massiliense to combination antibiotic therapies containing clarithromycin was excellent. Distinguishing between M. massiliense and M. abscessus has major clinical implications for CF patients.


Journal of Clinical Microbiology | 2005

Clinical and microbiological features of Inquilinus sp. isolates from five patients with cystic fibrosis.

R. Chiron; Hélène Marchandin; François Counil; Estelle Jumas-Bilak; Anne-Marie Freydière; Gabriel Bellon; Marie-Odile Husson; Dominique Turck; François Brémont; Gérard Chabanon; Christine Segonds

ABSTRACT Patients with cystic fibrosis (CF) may be colonized with unusual gram-negative bacilli whose identification is difficult and clinical impact unclear. We describe the clinical and microbiological features of five colonizations with organisms belonging to the recently described genus Inquilinus in CF patients. Isolates were identified from Burkholderia cepacia selective medium by means of 16S rRNA analysis. All of them were resistant to colistin, penicillins, cephalosporins, and monobactams but exhibited a remarkable susceptibility to imipenem. One of the five patients was transiently colonized with a nonmucoid isolate, whereas the four other patients were persistently colonized over the period of follow-up (8 to 21 months) with mucoid isolates. Pulsed-field gel electrophoresis of SpeI-digested genomic DNA was powerful for strain genotyping and demonstrated the clonality of Inquilinus sp. colonization for the two patients tested. Clinical evolution after the onset of Inquilinus was heterogeneous, but for at least one patient the lung function worsened and eradication of Inquilinus sp. was unsuccessful despite several imipenem courses. Finally, Inquilinus spp. may represent a new threat for CF patients due to their mucoid characteristic, their multiresistant pattern to antibiotics, and their ability to persist in the respiratory tract.


Clinical Microbiology and Infection | 2014

Effectiveness of bacteriophages in the sputum of cystic fibrosis patients

Emilie Saussereau; Isabelle Vachier; R. Chiron; Benoit Godbert; Isabelle Sermet; Nicolas Dufour; Jean-Paul Pirnay; Daniel De Vos; Frédérique Carrié; Nicolas Molinari; Laurent Debarbieux

Bacteriophages have been shown to be effective for treating acute infections of the respiratory tract caused by antibiotic-resistant bacteria in animal models, but no evidence has yet been presented of their activity against pathogens in complex biological samples from chronically infected patients. We assessed the efficacy of a cocktail of ten bacteriophages infecting Pseudomonasxa0aeruginosa following its addition to 58 sputum samples from cystic fibrosis (CF) patients collected at three different hospitals. Ten samples that did not contain P.xa0aeruginosa were not analysed further. In the remaining 48 samples, the addition of bacteriophages led to a significant decrease in the levels of P.xa0aeruginosa strains, as shown by comparison with controls, taking two variables (time and bacteriophages) into account (pxa0=xa00.024). In 45.8% of these samples, this decrease was accompanied by an increase in the number of bacteriophages. We also tested each of the ten bacteriophages individually against 20 colonies from each of these 48 samples and detected bacteriophage-susceptible bacteria in 64.6% of the samples. An analysis of the clinical data revealed no correlation between patient age, sex, duration of P.xa0aeruginosa colonization, antibiotic treatment, FEV1 (forced expiratory volume in the first second) and the efficacy of bacteriophages. The demonstration that bacteriophages infect their bacterial hosts in the sputum environment, regardless of the clinical characteristics of the patients, represents a major step towards the development of bacteriophage therapy to treat chronic lung infections.


PLOS ONE | 2012

Lipoxin A4 Stimulates Calcium-Activated Chloride Currents and Increases Airway Surface Liquid Height in Normal and Cystic Fibrosis Airway Epithelia

Valia Verriere; Gerard Higgins; Mazen Al-Alawi; Richard W. Costello; Paul McNally; R. Chiron; Brian J. Harvey; V. Urbach

Cystic Fibrosis (CF) is a genetic disease characterised by a deficit in epithelial Cl− secretion which in the lung leads to airway dehydration and a reduced Airway Surface Liquid (ASL) height. The endogenous lipoxin LXA4 is a member of the newly identified eicosanoids playing a key role in ending the inflammatory process. Levels of LXA4 are reported to be decreased in the airways of patients with CF. We have previously shown that in normal human bronchial epithelial cells, LXA4 produced a rapid and transient increase in intracellular Ca2+. We have investigated, the effect of LXA4 on Cl− secretion and the functional consequences on ASL generation in bronchial epithelial cells obtained from CF and non-CF patient biopsies and in bronchial epithelial cell lines. We found that LXA4 stimulated a rapid intracellular Ca2+ increase in all of the different CF bronchial epithelial cells tested. In non-CF and CF bronchial epithelia, LXA4 stimulated whole-cell Cl− currents which were inhibited by NPPB (calcium-activated Cl− channel inhibitor), BAPTA-AM (chelator of intracellular Ca2+) but not by CFTRinh-172 (CFTR inhibitor). We found, using confocal imaging, that LXA4 increased the ASL height in non-CF and in CF airway bronchial epithelia. The LXA4 effect on ASL height was sensitive to bumetanide, an inhibitor of transepithelial Cl− secretion. The LXA4 stimulation of intracellular Ca2+, whole-cell Cl− currents, conductances and ASL height were inhibited by Boc-2, a specific antagonist of the ALX/FPR2 receptor. Our results provide, for the first time, evidence for a novel role of LXA4 in the stimulation of intracellular Ca2+ signalling leading to Ca2+-activated Cl− secretion and enhanced ASL height in non-CF and CF bronchial epithelia.


Journal of Clinical Microbiology | 2010

Gluconobacter as Well as Asaia Species, Newly Emerging Opportunistic Human Pathogens among Acetic Acid Bacteria

Corentine Alauzet; Corinne Teyssier; Estelle Jumas-Bilak; Anne Gouby; R. Chiron; Christian Rabaud; François Counil; Alain Lozniewski; Hélène Marchandin

ABSTRACT Acetic acid bacteria (AAB) are broadly used in industrial food processing. Among them, members of the genera Asaia, Acetobacter, and Granulibacter were recently reported to be human opportunistic pathogens. We isolated AAB from clinical samples from three patients and describe here the clinical and bacteriological features of these cases. We report for the first time (i) the isolation of a Gluconobacter sp. from human clinical samples; (ii) the successive isolation of different AAB, i.e., an Asaia sp. and two unrelated Gluconobacter spp., from a cystic fibrosis patient; and (iii) persistent colonization of the respiratory tract by a Gluconobacter sp. in this patient. We reviewed the main clinical features associated with AAB isolation identified in the 10 documented reports currently available in the literature. Albeit rare, infections as well as colonization with AAB are increasingly reported in patients with underlying chronic diseases and/or indwelling devices. Clinicians as well as medical microbiologists should be aware of these unusual opportunistic pathogens, which are difficult to detect during standard medical microbiological investigations and which are multiresistant to antimicrobial agents. Molecular methods are required for identification of genera of AAB, but the results may remain inconclusive for identification to the species level.


European Respiratory Journal | 2015

Transcription factors and miRNAs that regulate fetal to adult CFTR expression change are new targets for cystic fibrosis.

Victoria Viart; Anne Bergougnoux; Jennifer Bonini; Jessica Varilh; R. Chiron; Olivier Tabary; Nicolas Molinari; Mireille Claustres; Magali Taulan-Cadars

The CFTR gene displays a tightly regulated tissue-specific and temporal expression. Mutations in this gene cause cystic fibrosis (CF). In this study we wanted to identify trans-regulatory elements responsible for CFTR differential expression in fetal and adult lung, and to determine the importance of inhibitory motifs in the CFTR-3′UTR with the aim of developing new tools for the correction of disease-causing mutations within CFTR. We show that lung development-specific transcription factors (FOXA, C/EBP) and microRNAs (miR-101, miR-145, miR-384) regulate the switch from strong fetal to very low CFTR expression after birth. By using miRNome profiling and gene reporter assays, we found that miR-101 and miR-145 are specifically upregulated in adult lung and that miR-101 directly acts on its cognate site in the CFTR-3′UTR in combination with an overlapping AU-rich element. We then designed miRNA-binding blocker oligonucleotides (MBBOs) to prevent binding of several miRNAs to the CFTR-3′UTR and tested them in primary human nasal epithelial cells from healthy individuals and CF patients carrying the p.Phe508del CFTR mutation. These MBBOs rescued CFTR channel activity by increasing CFTR mRNA and protein levels. Our data offer new understanding of the control of the CFTR gene regulation and new putative correctors for cystic fibrosis. Transcription factors/miRNAs that regulate fetal to adult CFTR expression change are new targets for CF treatment http://ow.ly/zEgYQ

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Pascal Chanez

Aix-Marseille University

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Jessica Varilh

University of Montpellier

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Marc Humbert

Université Paris-Saclay

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