190 results on '"Smyth AR"'
Search Results
2. Intestinal function and transit associate with gut microbiota dysbiosis in cystic fibrosis
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Marsh, R, Gavillet, H, Hanson, L, Ng, C, Mitchell-Whyte, M, Major, G, Smyth, AR, Rivett, D, van der Gast, C, Marsh, R, Gavillet, H, Hanson, L, Ng, C, Mitchell-Whyte, M, Major, G, Smyth, AR, Rivett, D, and van der Gast, C
- Abstract
Background: Most people with cystic fibrosis (pwCF) suffer from gastrointestinal symptoms and are at risk of gut complications. Gut microbiota dysbiosis is apparent within the CF population across all age groups, with evidence linking dysbiosis to intestinal inflammation and other markers of health. This pilot study aimed to investigate the potential relationships between the gut microbiota and gastrointestinal physiology, transit, and health. Study design: Faecal samples from 10 pwCF and matched controls were subject to 16S rRNA sequencing. Results were combined with clinical metadata and MRI metrics of gut function to investigate relationships. Results: pwCF had significantly reduced microbiota diversity compared to controls. Microbiota compositions were significantly different, suggesting remodelling of core and rarer satellite taxa in CF. Dissimilarity between groups was driven by a variety of taxa, including Escherichia coli, Bacteroides spp., Clostridium spp., and Faecalibacterium prausnitzii. The core taxa were explained primarily by CF disease, whilst the satellite taxa were associated with pulmonary antibiotic usage, CF disease, and gut function metrics. Species-specific ordination biplots revealed relationships between taxa and the clinical or MRI-based variables observed. Conclusions: Alterations in gut function and transit resultant of CF disease are associated with the gut microbiota composition, notably the satellite taxa. Delayed transit in the small intestine might allow for the expansion of satellite taxa resulting in potential downstream consequences for core community function in the colon.
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- 2022
3. Working in partnership with the patient community to develop outline trial designs in CF
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Rowbotham, NJ, primary, Smith, S, additional, Davies, G, additional, Leighton, P, additional, Rayner, O, additional, Elliott, Z, additional, Daniels, T, additional, and Smyth, AR, additional
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- 2021
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4. An ex vivo cystic fibrosis model recapitulates key clinical aspects of chronic Staphylococcus aureus infection
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Sweeney E, Harrington NE, Harley Henriques AG, Hassan MM, Crealock-Ashurst B, Smyth AR, Hurley MN, Tormo-Mas MÁ, and Harrison F
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respiratory system ,3Rs, Cystic fibrosis, antimicrobial resistance, biofilm, chronic infection, small colony variant - Abstract
Staphylococcus aureus is the most prevalent organism isolated from the airways of people with cystic fibrosis (CF), predominantly early in life. Yet its role in the pathology of lung disease is poorly understood. In mice, and many experiments using cell lines, the bacterium invades cells or interstitium, and forms abscesses. This is at odds with the limited available clinical data: interstitial bacteria are rare in CF biopsies and abscesses are highly unusual. Bacteria instead appear to localize in mucus plugs in the lumens of bronchioles. We show that, in an established ex vivo model of CF infection comprising porcine bronchiolar tissue and synthetic mucus, S. aureus demonstrates clinically significant characteristics including colonization of the airway lumen, with preferential localization as multicellular aggregates in mucus, initiation of a small colony variant phenotype and increased antibiotic tolerance of tissue-associated aggregates. Tissue invasion and abscesses were not observed. Our results may inform ongoing debates relating to clinical responses to S. aureus in people with CF.
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- 2021
5. Model Systems to Study the Chronic, Polymicrobial Infections in Cystic Fibrosis: Current Approaches and Exploring Future Directions
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O’Toole, GA, Crabbé, A, Kümmerli, R, LiPuma, JJ, Bomberger, JM, Davies, JC, Limoli, D, Phelan, VV, Bliska, JB, DePas, WH, Dietrich, LE, Hampton, TH, Hunter, R, Khursigara, CM, Price-Whelan, A, Ashare, A, Cramer, RA, Goldberg, JB, Harrison, F, Hogan, DA, Henson, MA, Madden, DR, Mayers, JR, Nadell, C, Newman, D, Prince, A, Rivett, DW, Schwartzman, JD, Schultz, D, Sheppard, DC, Smyth, AR, Spero, MA, Stanton, BA, Turner, PE, van der Gast, C, Whelan, FJ, Whitaker, R, Whiteson, K, O’Toole, GA, Crabbé, A, Kümmerli, R, LiPuma, JJ, Bomberger, JM, Davies, JC, Limoli, D, Phelan, VV, Bliska, JB, DePas, WH, Dietrich, LE, Hampton, TH, Hunter, R, Khursigara, CM, Price-Whelan, A, Ashare, A, Cramer, RA, Goldberg, JB, Harrison, F, Hogan, DA, Henson, MA, Madden, DR, Mayers, JR, Nadell, C, Newman, D, Prince, A, Rivett, DW, Schwartzman, JD, Schultz, D, Sheppard, DC, Smyth, AR, Spero, MA, Stanton, BA, Turner, PE, van der Gast, C, Whelan, FJ, Whitaker, R, and Whiteson, K
- Abstract
A recent workshop titled “Developing Models to Study Polymicrobial Infections,” sponsored by the Dartmouth Cystic Fibrosis Center (DartCF), explored the development of new models to study the polymicrobial infections associated with the airways of persons with cystic fibrosis (CF). The workshop gathered 351 investigators over two virtual sessions. Here, we present the findings of this workshop, summarize some of the challenges involved with developing such models, and suggest three frameworks to tackle this complex problem. The frameworks proposed here, we believe, could be generally useful in developing new model systems for other infectious diseases. Developing and validating new approaches to study the complex polymicrobial communities in the CF airway could open windows to new therapeutics to treat these recalcitrant infections, as well as uncovering organizing principles applicable to chronic polymicrobial infections more generally.
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- 2021
6. Development and Reporting of Prediction Models: Guidance for Authors From Editors of Respiratory, Sleep, and Critical Care Journals
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Leisman, DE, Harhay, MO, Lederer, DJ, Abramson, M, Adjei, AA, Bakker, J, Ballas, ZK, Barreiro, E, Bell, SC, Bellomo, R, Bernstein, JA, Branson, RD, Brusasco, V, Chalmers, JD, Chokroverty, S, Citerio, G, Collop, NA, Cooke, CR, Crapo, JD, Donaldson, G, Fitzgerald, DA, Grainger, E, Hale, L, Herth, FJ, Kochanek, PM, Marks, G, Moorman, JR, Ost, DE, Schatz, M, Sheikh, A, Smyth, AR, Stewart, I, Stewart, PW, Swenson, ER, Szymusiak, R, Teboul, J-L, Vincent, J-L, Wedzicha, JA, Maslove, DM, Leisman, DE, Harhay, MO, Lederer, DJ, Abramson, M, Adjei, AA, Bakker, J, Ballas, ZK, Barreiro, E, Bell, SC, Bellomo, R, Bernstein, JA, Branson, RD, Brusasco, V, Chalmers, JD, Chokroverty, S, Citerio, G, Collop, NA, Cooke, CR, Crapo, JD, Donaldson, G, Fitzgerald, DA, Grainger, E, Hale, L, Herth, FJ, Kochanek, PM, Marks, G, Moorman, JR, Ost, DE, Schatz, M, Sheikh, A, Smyth, AR, Stewart, I, Stewart, PW, Swenson, ER, Szymusiak, R, Teboul, J-L, Vincent, J-L, Wedzicha, JA, and Maslove, DM
- Abstract
Prediction models aim to use available data to predict a health state or outcome that has not yet been observed. Prediction is primarily relevant to clinical practice, but is also used in research, and administration. While prediction modeling involves estimating the relationship between patient factors and outcomes, it is distinct from casual inference. Prediction modeling thus requires unique considerations for development, validation, and updating. This document represents an effort from editors at 31 respiratory, sleep, and critical care medicine journals to consolidate contemporary best practices and recommendations related to prediction study design, conduct, and reporting. Herein, we address issues commonly encountered in submissions to our various journals. Key topics include considerations for selecting predictor variables, operationalizing variables, dealing with missing data, the importance of appropriate validation, model performance measures and their interpretation, and good reporting practices. Supplemental discussion covers emerging topics such as model fairness, competing risks, pitfalls of "modifiable risk factors", measurement error, and risk for bias. This guidance is not meant to be overly prescriptive; we acknowledge that every study is different, and no set of rules will fit all cases. Additional best practices can be found in the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines, to which we refer readers for further details.
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- 2020
7. Is cystic fibrosis survival improving in excess to that of the general population for England and Wales and the USA?
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Hurley, MN, McKeever, T, Prayle, AP, Fogarty, A, and Smyth, AR
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- 2012
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8. G268 The james lind alliance and cystic fibrosis: a journey towards co-production of research
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Rowbotham, NJ, primary, Smith, SJ, additional, Elliott, ZC, additional, and Smyth, AR, additional
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- 2020
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9. G272 Intensive care admissions in children with down syndrome: trends in incidence and outcome
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Rapaport, B, primary, Marder, E, additional, Smyth, AR, additional, Parslow, RC, additional, Vyas, H, additional, and Prayle, AP, additional
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- 2020
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10. Working in partnership with the patient community to develop outline trial designs in CF
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Rowbotham, NJ, Smith, S, Davies, G, Leighton, P, Rayner, O, Elliott, Z, Daniels, T, and Smyth, AR
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- 2022
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11. THE PROTEKT STUDY - A PHASE IIA, RANDOMISED, CONTROLLED, OPEN-LABEL TRIAL OF ROSUVASTATIN FOR THE PREVENTION OF AMINOGLYCOSIDE-INDUCED KIDNEY TOXICITY IN CHILDREN WITH CYSTIC FIBROSIS
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McWilliam, SJ, Antoine, DJ, Rosala-Hallas, A, Jones, A, MacLean, C, Prayle, A, Smyth, AR, Flaherty, L, Shaw, VE, Greenhalf, W, Smyth, RL, and Pirmohamed, M
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- 2017
12. The pharmacokinetics and toxicity of morning vs. evening tobramycin dosing for pulmonary exacerbations of cystic fibrosis: A randomised comparison
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Prayle, AP, Jain, K, Touw, DJ, Koch, Birgit, Knox, AJ, Watson, A, Smyth, AR, Prayle, AP, Jain, K, Touw, DJ, Koch, Birgit, Knox, AJ, Watson, A, and Smyth, AR
- Abstract
Background: Circadian variation in renal toxicity of aminoglycosides has been demonstrated in animal and human studies. People with CF are frequently prescribed aminoglycosides. Altered pharmacokinetics of aminoglycosides are predictive of toxicity. Aim: To investigate whether the time of day of aminoglycoside administration modulates renal excretion of tobramycin and toxicity in children with CF. To determine whether circadian rhythms are disrupted in children with CF during hospital admission. Methods: Children (age 5-18 years) with CF scheduled for tobramycin therapy were randomly allocated to receive tobramycin at 0800 or 2000 h. Serum tobramycin levels were drawn at 1 h and between 3.5 and 5 h post-infusion between days 5 and 9 of therapy. Melatonin levels were measured serially at intervals from 1800 h in the evening until 1200 h on the next day. Circadian rhythm was categorised as normal when dim light melatonin onset was demonstrated between 1800 and 2200 h and/or peak melatonin levels were observed during the night. Weight and spirometry were measured at the start and end of the therapy. Urinary biomarkers of kidney toxicity (KIM1 NAG, NGAL, IL-18 and CysC) were assayed at the start and end of the course of tobramycin. Results: Eighteen children were recruited to the study. There were no differences in renal clearance between the morning and evening groups. The increase in urinary KIM-1 was greater in the evening dosage group compared to the morning group (mean difference, 0.73 ng/mg; 95% CI, 0.14 to 1.32; p = 0.018). There were no differences in the other urinary biomarkers. There was normal circadian rhythm in 7/11 participants (64%). Conclusions: Renal elimination of tobramycin was not affected by the time of day of administration. Urinary KIM-1 raises the possibility of greater nephrotoxicity with evening administration. Four children showed disturbed circadian rhythm and high melatonin levels (ClinicalTrials.gov NCT01207245). (C) 2015 The Authors. Publ
- Published
- 2016
13. Biological activity exceeds biogenic structure in influencing sediment nitrogen cycling in experimental oyster reefs
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Smyth, AR, primary, Geraldi, NR, additional, Thompson, SP, additional, and Piehler, MF, additional
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- 2016
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14. Oyster-mediated benthic-pelagic coupling modifies nitrogen pools and processes
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Smyth, AR, primary, Geraldi, NR, additional, and Piehler, MF, additional
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- 2013
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15. Effect of aquacultured oyster biodeposition on sediment N2 production in Chesapeake Bay
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Higgins, CB, primary, Tobias, C, additional, Piehler, MF, additional, Smyth, AR, additional, Dame, RF, additional, Stephenson, K, additional, and Brown, BL, additional
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- 2013
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16. Aminoglycoside use in cystic fibrosis: therapeutic strategies and toxicity.
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Prayle A, Smyth AR, Prayle, Andrew, and Smyth, Alan R
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- 2010
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17. A study of a single high potency multivitamin preparation in the management of cystic fibrosis.
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Leonard CH, Ross-Wilson C, Smyth AR, Polnay J, Range SP, and Knox AJ
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Background: ADEKs is a new multivitamin preparation formulated specifically for cystic fibrosis (CF) patients, containing all four fat-soluble vitamins. There is no data currently available on its use in CF. Method: We carried out a retrospective study to evaluate ADEKs in 54 CF patients attending the specialist CF Unit at Nottingham City Hospital. Plasma vitamin A and E levels were collected from annual review reports when taking ADEKs and a year previously when using other vitamin preparations. Dietary assessment data was available for 24 of these patients (11 children, 13 adults). Results: ADEKs was taken for a median of 9.5 months by 19 children (mean age 11.3 years; range 7-15 years) and for 4 months by 35 adults (mean age 24 years; range 17-36 years). Median plasma vitamin A levels were significantly higher (P<0.05) for all age groups (27% increase for 7-10 year olds, 48% increase for 11-15 year olds, 100% increase for 16 + year olds) following the change from other vitamin supplements to ADEKs. Median plasma vitamin E levels were also significantly higher (59% increase for 7-10 year olds; 16% increase for 11-15 year olds; 26% increase for 16+ year olds). Fifteen (28%) and 9 (17%) patients went from below to within the normal plasma reference range for vitamins A and E, respectively, when changed onto ADEKs. Four (7%) and 11 (20%) patients had values above the normal plasma range for vitamins A and E, respectively, whilst on ADEKs. Conclusion: This study suggests that ADEKs tablets are useful for CF patients aged over 10 years as plasma vitamin A and E levels were improved. The use of a single vitamin preparation such as ADEKs is likely to improve compliance. We have reservations over its use amongst the 7-10 year olds because of high plasma vitamin A (3/9) and E (7/9) levels, although further research may ultimately endorse its future use within this group. [ABSTRACT FROM AUTHOR]
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- 1998
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18. Birth cohorts in childhood asthma: lessons and limitations.
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Smyth AR
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- 2012
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19. A longitudinal study assessing the impact of elexacaftor/tezacaftor/ivacaftor on gut transit and function in people with cystic fibrosis using magnetic resonance imaging (MRI).
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Yule A, Ng C, Recto A, Lockwood F, Dellschaft NS, Hoad CL, Zagoya C, Mainz JG, Major G, Barr HL, Gowland PA, Stewart I, Marciani L, Spiller RC, and Smyth AR
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- Humans, Male, Female, Longitudinal Studies, Prospective Studies, Adult, Adolescent, Drug Combinations, Chloride Channel Agonists therapeutic use, Quinolones therapeutic use, Pyridines therapeutic use, Pyridines pharmacology, Cystic Fibrosis Transmembrane Conductance Regulator, Child, Quinolines therapeutic use, Quinolines pharmacology, Young Adult, Pyrrolidines therapeutic use, Cystic Fibrosis drug therapy, Cystic Fibrosis physiopathology, Magnetic Resonance Imaging methods, Benzodioxoles therapeutic use, Gastrointestinal Transit drug effects, Aminophenols therapeutic use, Pyrazoles therapeutic use, Pyrazoles pharmacology, Indoles therapeutic use
- Abstract
Background: Gastrointestinal (GI) symptoms in cystic fibrosis (CF) are common and disruptive. The effect of cystic fibrosis transmembrane conductance regulator (CFTR) modulators on the GI tract is not fully understood. The aim was to use magnetic resonance imaging (MRI) to determine if elexacaftor/tezacaftor/ivacaftor (ETI) changed GI function and transit., Methods: This was an 18 month prospective, longitudinal, observational study. We enrolled 24 people with CF aged 12 years or older to undergo MRI scans before starting ETI and 3, 6, and 18 months after starting ETI. The primary outcome measure was change in oro-caecal transit time (OCTT) at 6 and 18 months. Secondary outcome measures included change in small bowel water content (SBWC), change in the reduction in small bowel water content following a meal (DeltaSBWC) and change in total colonic volume (TCV)., Results: A total of 21 participants completed MRI scans at 6 months and 11 completed at 18 months. After 18 months of ETI, median OCTT significantly reduced, from >360 min [IQR 240->360] to 240 min [IQR 180-300] (p = 0.02, Wilcoxon signed-rank). Both SBWC and DeltaSBWC increased after starting ETI. TCV reduced significantly after 18 months (p = 0.005, Friedman)., Conclusions: Our findings suggest an improvement in small bowel transit, small bowel response to food and a reduction in colonic volume after starting ETI. These effects may relate to CFTR activation in the small bowel. To our knowledge this is the first study to show a physiological change in GI transit and function in response to CFTR modulator use through imaging studies., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: AR, CH, FL, and ND have nothing to disclose. This work was supported by an investigator-initiated grant from Vertex Pharmaceuticals including salary support for AY and CN. CZ reports an investigator-initiated grant from Vertex Pharmaceuticals. JGM reports investigator-initiated grants from Vertex Pharmaceuticals and has received honoraria previously for lectures from Vertex, Pari and Chiesi. JGM also reports participation in monitoring or advisory board previously for Vertex, Viatris and Chiesi. GM reports investigator-initiated grants from Vertex Pharmaceuticals. GM also reports previous employment to Société Produits Nestlé during this study period. GM reports receiving support to attend conferences from Société Produits Nestlé previously. PG reports investigator-initiated grants from Vertex Pharmaceuticals paid to their institution. IS reports grants from the Rayne Foundation Fellowship. LM reports grants from Vertex Pharmaceuticals, Cystic Fibrosis Trust and Cystic Fibrosis Foundation paid to their institution. RS reports grants from Sanofi and Société Produits Nestlé paid to their institution and payments for consultation from Enterobiotix. ARS reports grants from Vertex pharmaceuticals paid to their institution and grants from the Cystic Fibrosis Trust and Cystic Fibrosis Foundation. ARS has previously been part of an advisory board from Viatris Pharmaceuticals (outside this current work). ARS and HLB hold a patent issued “Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof”. ARS reports membership of the Data Safety Monitoring Board of the Cystic Fibrosis Foundation. HLB reports grants from Cystic Fibrosis Trust, Cystic Fibrosis Foundation, LifeArc and is a board member and chief medical officer for MiDx(Ⓡ) company., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2024
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20. Impact of extended Elexacaftor/Tezacaftor/Ivacaftor therapy on the gut microbiome in cystic fibrosis.
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Marsh R, Santos CD, Yule A, Dellschaft NS, Hoad CL, Ng C, Major G, Smyth AR, Rivett D, and van der Gast C
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- Humans, Female, Male, Pilot Projects, Adult, Pyrazoles therapeutic use, Drug Combinations, Pyrroles administration & dosage, Pyrroles therapeutic use, Chloride Channel Agonists therapeutic use, Feces microbiology, Pyridines, Adolescent, Longitudinal Studies, Young Adult, Cystic Fibrosis Transmembrane Conductance Regulator genetics, Pyrrolidines, Cystic Fibrosis microbiology, Cystic Fibrosis drug therapy, Gastrointestinal Microbiome drug effects, Benzodioxoles therapeutic use, Quinolones therapeutic use, Aminophenols therapeutic use, Indoles therapeutic use
- Abstract
Background: There is a paucity of knowledge on the longer-term effects of CF transmembrane conductance regulator (CFTR) modulator therapies upon the gut microbiome and associated outcomes. In a pilot study, we investigated longitudinal Elexacaftor/Tezacaftor/Ivacaftor (ETI) therapy on the gut microbiota, metabolomic functioning, and clinical outcomes in people with CF (pwCF)., Study Design: Faecal samples from 20 pwCF were acquired before and then following 3, 6, and 17+ months of ETI therapy. Samples were subjected to microbiota sequencing and targeted metabolomics to profile and quantify short-chain fatty acid composition. Ten healthy matched controls were included for comparison. Clinical data, including markers of intestinal function were integrated to investigate relationships., Results: Extended ETI therapy increased core microbiota diversity and composition, which translated to gradual shifts in whole microbiota composition towards that observed in healthy controls. Despite becoming more similar over time, CF microbiota and functional metabolite compositions remained significantly different to healthy controls. Antibiotic treatment for pulmonary infection significantly explained a relatively large degree of variation within the whole microbiota and rarer satellite taxa. Clinical outcomes were not significantly different following ETI., Conclusions: Whilst differences persisted, a positive trajectory towards the microbiota observed in healthy controls was found. We posit that progression was predominately impeded by pulmonary antibiotics administration. We recommend future studies use integrated omics approaches within a combination of long-term longitudinal patient studies and model experimental systems. This will deepen our understanding of the impacts of CFTR modulator therapy and respiratory antibiotic interventions upon the gut microbiome and gastrointestinal pathophysiology in CF., Competing Interests: Declaration of competing interest RM, CDS, ND, and CH have nothing to disclose. DR and CvdG report grant funding from Vertex Pharmaceuticals outside of the submitted work. AY, CN, GM, and ARS report grants and speaker honorarium from Vertex Pharmaceuticals outside the submitted work., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2024
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21. Infection prevention and control in cystic fibrosis: An update of a systematic review of interventions.
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Rowbotham NJ, Smith S, Jahnke N, Milczanowski S, Elliott ZC, Prayle AP, and Smyth AR
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Preventing transmissible infection is a priority in cystic fibrosis (CF) care. This is an update of a systematic review of the evidence for infection prevention and control interventions in CF. Our full protocol can be found on PROSPERO (CRD42018109999). We searched for studies and guidelines which included interventions for infection prevention and control in CF. We included 39 studies and 7 guidelines. Strategies included: cohort or individual segregation, hand hygiene, facemasks, equipment, enhanced adherence or a combination of these. Many studies showed a reduction in transmission with segregation. However, the certainty of evidence (using GRADE) was low or very low. Most guideline recommendations have little evidence to support them, with no updates since our original review. Undertaking RCTs in this area is ethically difficult. Large-scale registry-based studies may be the best pragmatic approach. Benefits of infection control must be balanced against the intrusion in the lives of people with CF., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: NR reports support for attending meetings and/or travel from the Cystic Fibrosis Trust, British Paediatric Respiratory Society and European Cystic Fibrosis Society, all outside the current work. AP reports grants or contracts from Vertex Pharmaceuticals, Cystic Fibrosis Trust, Action for AT, Nottingham University Hospitals Charity, SBRI and support for attending meetings and/or travel from Vertex Ltd and Quince Therapeutics, all outside the current work. AS has research grants (paid to the University of Nottingham) from Vertex Pharmaceuticals and payment for an advisory board (paid to the University of Nottingham) from Viatris Pharmaceuticals, all outside the current work. AS has patents issued (Camara M, Williams P, Barrett D, Halliday N, Knox A, Smyth A, Fogarty A, Barr H, Forrester D. Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof. US-2016131648-A1; https://pubchem.ncbi.nlm.nih.gov/patent/US-2016131648-A1 Outside the current work. AS reports participation on a Data Safety Monitoring Board for the North American Cystic Fibrosis Foundation Therapeutic Development Network, outside the current work. SS, NJ, ZE and SM have no competing interests, (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2024
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22. Bronchoscopy-guided antimicrobial therapy for cystic fibrosis.
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Jain K, Wainwright CE, and Smyth AR
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- Humans, Child, Anti-Bacterial Agents therapeutic use, Respiratory Tract Infections drug therapy, Respiratory Tract Infections microbiology, Adult, Bronchoalveolar Lavage, Adolescent, Child, Preschool, Pseudomonas aeruginosa isolation & purification, Cystic Fibrosis microbiology, Cystic Fibrosis drug therapy, Bronchoscopy, Randomized Controlled Trials as Topic
- Abstract
Background: Early diagnosis and treatment of lower respiratory tract infections is the mainstay of management of lung disease in cystic fibrosis (CF). When sputum samples are unavailable, diagnosis relies mainly on cultures from oropharyngeal specimens; however, there are concerns about whether this approach is sensitive enough to identify lower respiratory organisms. Bronchoscopy and related procedures such as bronchoalveolar lavage (BAL) are invasive but allow the collection of lower respiratory specimens from non-sputum producers. Cultures of bronchoscopic specimens provide a higher yield of organisms compared to those from oropharyngeal specimens. Regular use of bronchoscopy and related procedures may increase the accuracy of diagnosis of lower respiratory tract infections and improve the selection of antimicrobials, which may lead to clinical benefits. This is an update of a previous review that was first published in 2013 and was updated in 2016 and in 2018., Objectives: To evaluate the use of bronchoscopy-guided (also known as bronchoscopy-directed) antimicrobial therapy in the management of lung infection in adults and children with cystic fibrosis., Search Methods: We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched three registries of ongoing studies and the reference lists of relevant articles and reviews. The date of the most recent searches was 1 November 2023., Selection Criteria: We included randomised controlled studies involving people of any age with CF that compared the outcomes of antimicrobial therapies guided by the results of bronchoscopy (and related procedures) versus those guided by any other type of sampling (e.g. cultures from sputum, throat swab and cough swab)., Data Collection and Analysis: Two review authors independently selected studies, assessed their risk of bias and extracted data. We contacted study investigators for further information when required. We assessed the certainty of the evidence using the GRADE criteria., Main Results: We included two studies in this updated review. One study enrolled 170 infants under six months of age who had been diagnosed with CF through newborn screening. Participants were followed until they were five years old, and data were available for 157 children. The study compared outcomes for pulmonary exacerbations following treatment directed by BAL versus standard treatment based on clinical features and oropharyngeal cultures. The second study enrolled 30 children with CF aged between five and 18 years and randomised participants to receive treatment based on microbiological results of BAL triggered by an increase in lung clearance index (LCI) of at least one unit above baseline or to receive standard treatment based on microbiological results of oropharyngeal samples collected when participants were symptomatic. We judged both studies to have a low risk of bias across most domains, although the risk of bias for allocation concealment and selective reporting was unclear in the smaller study. In the larger study, the statistical power to detect a significant difference in the prevalence of Pseudomonas aeruginosa was low because Pseudomonas aeruginosa isolation in BAL samples at five years of age in both groups were much lower than the expected rate that was used for the power calculation. We graded the certainty of evidence for the key outcomes as low, other than for high-resolution computed tomography scoring and cost-of-care analysis, which we graded as moderate certainty. Both studies reported similar outcomes, but meta-analysis was not possible due to different ways of measuring the outcomes and different indications for the use of BAL. Whether antimicrobial therapy is directed by the use of BAL or standard care may make little or no difference in lung function z scores after two years (n = 29) as measured by the change from baseline in LCI and forced expiratory volume in one second (FEV1) (low-certainty evidence). At five years, the larger study found little or no difference between groups in absolute FEV1 z score or forced vital capacity (FVC) (low-certainty evidence). BAL-directed therapy probably makes little or no difference to any measure of chest scores assessed by computed tomography (CT) scan at either two or five years (different measures used in the two studies; moderate-certainty evidence). BAL-directed therapy may make little or no difference in nutritional parameters or in the number of positive isolates of P aeruginosa per participant per year, but may lead to more hospitalisations per year (1 study, 157 participants; low-certainty evidence). There is probably no difference in average cost of care per participant (either for hospitalisations or total costs) at five years between BAL-directed therapy and standard care (1 study, 157 participants; moderate-certainty evidence). We found no difference in health-related quality of life between BAL-directed therapy and standard care at either two or five years, and the larger study found no difference in the number of isolates of Pseudomonas aeruginosa per child per year. The eradication rate following one or two courses of eradication treatment and the number of pulmonary exacerbations were comparable in the two groups. Mild adverse events, when reported, were generally well tolerated. The most common adverse event reported was transient worsening of cough after 29% of procedures. Significant clinical deterioration was documented during or within 24 hours of BAL in 4.8% of procedures., Authors' Conclusions: This review, limited to two well-designed randomised controlled studies, shows no evidence to support the routine use of BAL for the diagnosis and management of pulmonary infection in preschool children with CF compared to the standard practice of providing treatment based on results of oropharyngeal culture and clinical symptoms. No evidence is available for adults., (Copyright © 2024 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)
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- 2024
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23. Standards for the care of people with cystic fibrosis (CF); Planning for a longer life.
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Gramegna A, Addy C, Allen L, Bakkeheim E, Brown C, Daniels T, Davies G, Davies JC, De Marie K, Downey D, Felton I, Hafkemeyer S, Hamouda S, Kendall V, Lindberg U, Macek M, Mayell S, Pearlsman O, Schechter MS, Salvatori L, Sands D, Schwarz C, Shteinberg M, Taylor J, Taylor-Cousar JL, Taylor-Robinson D, Watkins B, Verkleij M, Bevan A, Castellani C, Drevinek P, Gartner S, Lammertyn E, Landau EEC, Middleton PG, Plant BJ, Smyth AR, van Koningsbruggen-Rietschel S, Burgel PR, and Southern KW
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- Humans, Standard of Care, Quality of Life, Cystic Fibrosis therapy
- Abstract
This is the final of four papers updating standards for the care of people with CF. That this paper "Planning a longer life" was considered necessary, highlights how much CF care has progressed over the past decade. Several factors underpin this progress, notably increased numbers of people with CF with access to CFTR modulator therapy. As the landscape for CF changes, so do the hopes and aspirations of people with CF and their families. This paper reflects the need to consider people with CF not as a "problem" to be solved, but as a success, a potential and a voice to be heard. People with CF and the wider CF community have driven this approach, reflecting many of the topics in this paper. This exercise involved wide stakeholder engagement. People with CF are keen to contribute to research priorities and be involved in all stages of research. People with CF want healthcare professionals to respect them as individuals and consider the impact of our actions on the world around us. Navigating life presents challenges to all, but for people with CF these challenges are heightened and complex. In this paper we highlight the concerns and life moments that impact people with CF, and events that the CF team should aim to support, including the challenges around having a family. People with CF and their care teams must embrace the updated standards outlined in these four papers to enjoy the full potential for a healthier life., Competing Interests: Declaration of competing interest The authors had no declarations of interest in relation to the current work. Declarations of interest for each author outside the current work are summarised in Supplementary Table 4., (Copyright © 2024. Published by Elsevier B.V.)
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- 2024
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24. A randomised crossover trial of tezacaftor-ivacaftor for gut dysfunction in cystic fibrosis with magnetic resonance imaging (MRI) outcomes: a pilot study.
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Ng C, Dellschaft NS, Hoad C, Marciani L, Spiller R, Crooks C, Hill T, Menys A, Mainz JG, Barr H, Gowland PA, Major G, and Smyth AR
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Background: People with cystic fibrosis (CF) can experience recurrent chest infections, pancreatic exocrine insufficiency and gastrointestinal symptoms. New cystic fibrosis transmembrane conductance regulator (CFTR) modulator drugs improve lung function but gastrointestinal effects are unclear. We aimed to see if a CFTR modulator (tezacaftor-ivacaftor,TEZ/IVA) improves gastrointestinal outcomes in CF., Methods: We conducted a randomised, double-blind, placebo-controlled, two-period crossover trial (2019-2020) at Nottingham University Hospitals. The effects of TEZ/IVA on gut physiology were measured using MRI. Participants were randomly assigned to treatment sequences AB or BA (A:TEZ/IVA, B:placebo, each 28 days), with a 28-day washout period. Participants had serial MRI scans at baseline and after 19-23 days of each treatment. Due to the COVID-19 pandemic, a protocol amendment allowed for observer-blind comparisons prior to and during TEZ/IVA. In such cases, participants were not blind to the treatment but researchers remained blind. The primary outcome was oro-caecal transit time (OCTT). Secondary outcomes included MRI metrics, symptoms and stool biomarkers., Results: We randomised 13 participants. Before the COVID-19 pandemic 8 participants completed the full protocol and 1 dropped out. The remaining 4 participants followed the amended protocol. There were no significant differences between placebo and TEZ/IVA for OCTT (TEZ/IVA >360minutes [225,>360] vs. placebo 330minutes [285,>360], p=0.8) or secondary outcomes. There were no adverse events., Conclusions: Our data contribute to a research gap in the extra-pulmonary effects of CFTR modulators. We found no effect after TEZ/IVA on MRI metrics of gut function, GI symptoms or stool calprotectin. Effects might be detectable with larger studies, longer treatment or more effective CFTR modulators., Clinicaltrialsgov Registration: NCT04006873 (02/07/2019)., Competing Interests: Competing interests: NSD, CLD, LM, CC, TH, HLB, AJ, PG have nothing to disclose. CN, JGM and GM report grants and speaker honorarium from Vertex, outside the submitted work. GM is now an employee of Société Produits Nestlé S.A. who sell nutrition products and enzyme supplements for cystic fibrosis. AM is the CEO of Motilent Limited, a medical imaging analysis company. RS reports grants from Zespri International Ltd and Sanofi-Aventis, as well as lecturing fees from Menarini and Alfawasserman, outside the submitted work. ARS reports grants from Vertex, as well as speaker honoraria and expenses from Teva and Novartis and personal fees from Vertex, outside the submitted work. In addition, ARS and HLB have a patent issued “Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof”., (Copyright: © 2024 Ng C et al.)
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- 2024
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25. Standards for the care of people with cystic fibrosis (CF); recognising and addressing CF health issues.
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Burgel PR, Southern KW, Addy C, Battezzati A, Berry C, Bouchara JP, Brokaar E, Brown W, Azevedo P, Durieu I, Ekkelenkamp M, Finlayson F, Forton J, Gardecki J, Hodkova P, Hong G, Lowdon J, Madge S, Martin C, McKone E, Munck A, Ooi CY, Perrem L, Piper A, Prayle A, Ratjen F, Rosenfeld M, Sanders DB, Schwarz C, Taccetti G, Wainwright C, West NE, Wilschanski M, Bevan A, Castellani C, Drevinek P, Gartner S, Gramegna A, Lammertyn E, Landau EEC, Plant BJ, Smyth AR, van Koningsbruggen-Rietschel S, and Middleton PG
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- Humans, Europe, Societies, Medical, Cystic Fibrosis therapy
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This is the third in a series of four papers updating the European Cystic Fibrosis Society (ECFS) standards for the care of people with CF. This paper focuses on recognising and addressing CF health issues. The guidance was produced with wide stakeholder engagement, including people from the CF community, using an evidence-based framework. Authors contributed sections, and summary statements which were reviewed by a Delphi consultation. Monitoring and treating airway infection, inflammation and pulmonary exacerbations remains important, despite the widespread availability of CFTR modulators and their accompanying health improvements. Extrapulmonary CF-specific health issues persist, such as diabetes, liver disease, bone disease, stones and other renal issues, and intestinal obstruction. These health issues require multidisciplinary care with input from the relevant specialists. Cancer is more common in people with CF compared to the general population, and requires regular screening. The CF life journey requires mental and emotional adaptation to psychosocial and physical challenges, with support from the CF team and the CF psychologist. This is particularly important when life gets challenging, with disease progression requiring increased treatments, breathing support and potentially transplantation. Planning for end of life remains a necessary aspect of care and should be discussed openly, honestly, with sensitivity and compassion for the person with CF and their family. CF teams should proactively recognise and address CF-specific health issues, and support mental and emotional wellbeing while accompanying people with CF and their families on their life journey., Competing Interests: Declaration of competing interest The authors had no declarations of interest in relation to the current work. Declarations of interest for each author outside the current work are summarised in Supplementary Table 4., (Copyright © 2024. Published by Elsevier B.V.)
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- 2024
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26. A grumbling concern: A survey of gastrointestinal symptoms in cystic fibrosis in the modulator era.
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Calthorpe RJ, Goodchild N, Gleetus V, Premakumar V, Hayee B, Elliott Z, Evans B, Rowbotham NJ, Carr SB, Barr H, Horsley A, Peckham D, and Smyth AR
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Background: Gastrointestinal symptoms in cystic fibrosis (CF) are common and intrusive to daily life. Relieving gastrointestinal symptoms was identified as an important research priority and previously explored in an international survey in 2018. However, following the widespread introduction of cystic fibrosis transmembrane conductance regulator (CFTR) modulators in 2019, the landscape of CF treatment has changed. We repeated an online survey to further describe gastrointestinal symptoms and their effect on quality of life (QoL) in the CFTR modulator era., Methods: An electronic survey consisting of closed questions and free text responses was distributed via social media and professional networks for a period of one month between March - April 2022. People with CF (pwCF), their family and friends, and healthcare professionals (HCPs) were invited to take part., Results: There were 164 respondents: 88 pwCF (54%), 22 (13%) family, and 54 (33%) healthcare professionals (HCPs). A total of 89/110 (81%) pwCF or family members reported CFTR modulator treatment. The most commonly reported symptoms were wind / gas and rumbling stomach noises (borborygmi) in both the modulator and non-modulator groups in addition to loose motions (modulator group) and bloating (no modulator group). Abdominal pain and bloating had the greatest impact on QoL.For those on a CFTR modulator, the proportion of pwCF reporting "no change" or "worse" for all of the symptoms surveyed was greater than the proportion reporting an improvement. For some symptoms such as stomach pains and reduced appetite, improvements were perceived more commonly in HCPs than what was reported by pwCF. Following modulator introduction, dietary changes to manage GI symptoms were recommended by 28/35 (80%) of HCPs and reported by 38/76 (50%) lay respondents. Changes in medication were recommended by 19/35 (54%) HCPs and reported by 44/76 (58%) of patients and family members., Conclusion: This survey has shown that gastrointestinal symptoms remain prevalent in pwCF in the CFTR modulator era, though the nature of these symptoms may have changed. A better understanding of the underlying pathophysiology of these symptoms is essential. Future clinical studies should focus on improving symptoms and QoL., Competing Interests: Competing interests: A.R. Smyth has research grants (paid to the University of Nottingham) from Vertex Pharmaceuticals and payment for an advisory board (paid to the University of Nottingham) from Viatris Pharmaceuticals, all outside the current work. A.R. Smyth has patents issued (Camara M, Williams P, Barrett D, Halliday N, Knox A, Smyth A, Fogarty A, Barr H, Forrester D. Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof. US2016131648-A1; https://pubchem.ncbi.nlm.nih.gov/patent/US-2016131648-A1 Outside the current work, A.R. Smyth reports participation on a Data Safety Monitoring Board for the North American Cystic Fibrosis Foundation Therapeutic Development Network., (Copyright: © 2024 Calthorpe RJ et al.)
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- 2024
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27. Standards for the care of people with cystic fibrosis; establishing and maintaining health.
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Southern KW, Addy C, Bell SC, Bevan A, Borawska U, Brown C, Burgel PR, Button B, Castellani C, Chansard A, Chilvers MA, Davies G, Davies JC, De Boeck K, Declercq D, Doumit M, Drevinek P, Fajac I, Gartner S, Georgiopoulos AM, Gursli S, Gramegna A, Hansen CM, Hug MJ, Lammertyn E, Landau EEC, Langley R, Mayer-Hamblett N, Middleton A, Middleton PG, Mielus M, Morrison L, Munck A, Plant B, Ploeger M, Bertrand DP, Pressler T, Quon BS, Radtke T, Saynor ZL, Shufer I, Smyth AR, Smith C, and van Koningsbruggen-Rietschel S
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- Humans, Mutation, Cystic Fibrosis Transmembrane Conductance Regulator genetics, Cystic Fibrosis drug therapy, Electronic Nicotine Delivery Systems, Respiratory System Agents therapeutic use
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This is the second in a series of four papers updating the European Cystic Fibrosis Society (ECFS) standards for the care of people with CF. This paper focuses on establishing and maintaining health. The guidance is produced using an evidence-based framework and with wide stakeholder engagement, including people from the CF community. Authors provided a narrative description of their topic and statements, which were more directive. These statements were reviewed by a Delphi exercise, achieving good levels of agreement from a wide group for all statements. This guidance reinforces the importance of a multi-disciplinary CF team, but also describes developing models of care including virtual consultations. The framework for health is reinforced, including the need for a physically active lifestyle and the strict avoidance of all recreational inhalations, including e-cigarettes. Progress with cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy is reviewed, including emerging adverse events and advice for dose reduction and interruption. This paper contains guidance that is pertinent to all people with CF regardless of age and eligibility for and access to modulator therapy., Competing Interests: Declaration of competing interest KWS has no competing interests. See supplementary materials for full CoI statements for all authors., (Copyright © 2023. Published by Elsevier B.V.)
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- 2024
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28. Why and how should children be protected from the deluge of vaping related media and marketing overexposure?
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White D, Bush A, Smyth AR, and Bhatt JM
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E-cigarettes are products delivering nicotine via inhalation and are devised to mimic tobacco smoking. While they were initially introduced as a device putatively to aid with smoking cessation, their use is now far broader than that. Use by children is significantly increasing. There is growing evidence of the potential harms of vaping. E-liquids used for e-cigarettes contain a wide range of harmful substances, and the clinical consequences of this are now being increasingly demonstrated, such as the rise in cases of e-cigarette- or vaping-associated lung injury. In addition, early use may result in long-term nicotine addiction. Vaping companies utilise marketing methods that distinctly target young people, and weak legislation in the UK allows them free rein to expose children to vaping. In this review we demonstrate why children must be protected from vaping. We must have stringent legislation to prevent easy access to e-cigarettes, including banning the convenience and affordability disposable vapes provide, and prevent marketing that does not warn about the potential health effects. The Australia approach of prescription or pharmacy only access for smoking cessation should be considered to limit exposure of children and minimise use by nonsmokers., Competing Interests: Conflict of interest: A.R. Smyth reports research grants (paid to the University of Nottingham) from Vertex Pharmaceuticals (outside of the current work). Payment (to University of Nottingham) for attendance by A.R. Smyth at a Viatris advisory board. Patents issued (Camara M, Williams P, Barrett D, Halliday N, Knox A, Smyth A, Fogarty A, Barr H, Forrester D. Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof, US-2016131648-A1, https://pubchem.ncbi.nlm.nih.gov/patent/US-2016131648-A1) (outside of the current work). A.R. Smyth also reports participation on a Data Safety Monitoring Board for the North American Cystic Fibrosis Foundation Therapeutics Development Network (outside of the current work). J.M. Bhatt is a PI on studies sponsored by AstraZeneca and Boehringer Ingelheim; he has no personal (financial) interests in any pharmaceutical companies. J.M. Bhatt is a current member of the Breathe editorial board. The remaining authors have nothing to disclose., (Copyright ©ERS 2023.)
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- 2023
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29. Standards for the care of people with cystic fibrosis (CF): A timely and accurate diagnosis.
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Castellani C, Simmonds NJ, Barben J, Addy C, Bevan A, Burgel PR, Drevinek P, Gartner S, Gramegna A, Lammertyn E, Landau EEC, Middleton PG, Plant BJ, Smyth AR, van Koningsbruggen-Rietschel S, Girodon E, Kashirskaya N, Munck A, Nährlich L, Raraigh K, Sermet-Gaudelus I, Sommerburg O, and Southern KW
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- Infant, Newborn, Humans, Cystic Fibrosis Transmembrane Conductance Regulator genetics, Neonatal Screening methods, Cystic Fibrosis diagnosis, Cystic Fibrosis genetics, Cystic Fibrosis therapy
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There is considerable activity with respect to diagnosis in the field of cystic fibrosis (CF). This relates primarily to developments in newborn bloodspot screening (NBS), more extensive gene analysis and improved characterisation of CFTR-related disorder (CFTR-RD). This is particularly pertinent with respect to accessibility to variant-specific therapy (VST), a transformational intervention for people with CF with eligible CFTR gene variants. This advance reinforces the need for a timely and accurate diagnosis. In the future, there is potential for trials to assess effectiveness of variant-specific therapy for CFTR-RD. The guidance in this paper reaffirms previous standards, clarifies a number of issues, and integrates emerging evidence. Timely and accurate diagnosis has never been more important for people with CF., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023. Published by Elsevier B.V.)
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- 2023
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30. Prebiotics for people with cystic fibrosis.
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Williams NC, Jayaratnasingam J, Prayle AP, Nevitt SJ, and Smyth AR
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- Adult, Child, Humans, Feces, Hospitalization, Inflammation, Nutritional Status, Prebiotics, Cystic Fibrosis
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Background: Cystic fibrosis (CF) is a multisystem disease; the importance of growth and nutritional status is well established given their implications for lung function and overall survivability. Furthermore, it has been established that intestinal microbial imbalance and inflammation are present in people with CF. Oral prebiotics are commercially available substrates that are selectively utilised by host intestinal micro-organisms and may improve both intestinal and overall health., Objectives: To evaluate the benefits and harms of prebiotics for improving health outcomes in children and adults with CF., Search Methods: We searched the Cochrane Cystic Fibrosis Trials Register compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. Date of last search: 19 October 2022. We also searched PubMed and online trials registries. Date of last search: 13 January 2023., Selection Criteria: Randomised controlled trials (RCTs) and quasi-RCTs assessing the efficacy of prebiotics in children and adults with CF. We planned to only include the first treatment period from cross-over RCTs, regardless of washout period., Data Collection and Analysis: We did not identify any relevant trials., Main Results: We did not identify any relevant trials for inclusion in this review., Authors' Conclusions: This review did not find any evidence for the use of prebiotics in people with CF. Until such evidence is available, it is reasonable for clinicians to follow any local guidelines and to discuss the use of dietary prebiotics with their patients. Large and robust RCTs assessing the dietary prebiotics of inulin or galacto-oligosaccharides or fructo-oligosaccharides, or any combination of these, are needed. Such studies should be of at least 12 months in duration and assess outcomes such as growth and nutrition, gastrointestinal symptoms, pulmonary exacerbations, lung function, inflammatory biomarkers, hospitalisations, intestinal microbial profiling, and faecal short-chain fatty acids. Trials should include both children and adults and aim to be adequately powered to allow for subgroup analysis by age., (Copyright © 2023 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)
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- 2023
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31. Spatiotemporal diversity and community structure of cyanobacteria and associated bacteria in the large shallow subtropical Lake Okeechobee (Florida, United States).
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Lefler FW, Barbosa M, Zimba PV, Smyth AR, Berthold DE, and Laughinghouse HD
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Lake Okeechobee is a large eutrophic, shallow, subtropical lake in south Florida, United States. Due to decades of nutrient loading and phosphorus rich sediments, the lake is eutrophic and frequently experiences cyanobacterial harmful algal blooms (cyanoHABs). In the past, surveys of the phytoplankton community structure in the lake have been conducted by morphological studies, whereas molecular based studies have been seldom employed. With increased frequency of cyanoHABs in Lake Okeechobee (e.g., 2016 and 2018 Microcystis -dominated blooms), it is imperative to determine the diversity of cyanobacterial taxa that exist within the lake and the limnological parameters that drive bloom-forming genera. A spatiotemporal study of the lake was conducted over the course of 1 year to characterize the (cyano)bacterial community structure, using 16S rRNA metabarcoding, with coincident collection of limnological parameters (e.g., nutrients, water temperature, major ions), and cyanotoxins. The objectives of this study were to elucidate spatiotemporal trends of community structure, identify drivers of community structure, and examine cyanobacteria-bacterial relationships within the lake. Results indicated that cyanobacterial communities within the lake were significantly different between the wet and dry season, but not between periods of nitrogen limitation and co-nutrient limitation. Throughout the year, the lake was primarily dominated by the picocyanobacterium Cyanobium . The bloom-forming genera Cuspidothrix , Dolichospermum , Microcystis , and Raphidiopsis were highly abundant throughout the lake and had disparate nutrient requirements and niches within the lake. Anatoxin-a, microcystins, and nodularins were detected throughout the lake across both seasons. There were no correlated (cyano)bacteria shared between the common bloom-forming cyanobacteria Dolichospermum , Microcystis , and Raphidiopsis . This study is the first of its kind to use molecular based methods to assess the cyanobacterial community structure within the lake. These data greatly improve our understanding of the cyanobacterial community structure within the lake and the physiochemical parameters which may drive the bloom-forming taxa within Lake Okeechobee., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lefler, Barbosa, Zimba, Smyth, Berthold and Laughinghouse.)
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- 2023
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32. Tezacaftor/Ivacaftor therapy has negligible effects on the cystic fibrosis gut microbiome.
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Marsh R, Dos Santos C, Hanson L, Ng C, Major G, Smyth AR, Rivett D, and van der Gast C
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People with cystic fibrosis (pwCF) experience a range of persistent gastrointestinal symptoms throughout life. There is evidence indicating interaction between the microbiota and gut pathophysiology in CF. However, there is a paucity of knowledge on the potential effects of CF transmembrane conductance regulator (CFTR) modulator therapies on the gut microbiome. In a pilot study, we investigated the impact of Tezacaftor/Ivacaftor dual combination CFTR modulator therapy on the gut microbiota and metabolomic functioning in pwCF. Fecal samples from 12 pwCF taken at baseline and following placebo or Tezacaftor/Ivacaftor administration were subjected to microbiota sequencing and to targeted metabolomics to assess the short-chain fatty acid (SCFA) composition. Ten healthy matched controls were included as a comparison. Inflammatory calprotectin levels and patient symptoms were also investigated. No significant differences were observed in overall gut microbiota characteristics between any of the study stages, extended also across intestinal inflammation, gut symptoms, and SCFA-targeted metabolomics. However, microbiota and SCFA metabolomic compositions, in pwCF, were significantly different from controls in all study treatment stages. CFTR modulator therapy with Tezacaftor/Ivacaftor had negligible effects on both the gut microbiota and SCFA composition across the course of the study and did not alter toward compositions observed in healthy controls. Future longitudinal CFTR modulator studies will investigate more effective CFTR modulators and should use prolonged sampling periods, to determine whether longer-term changes occur in the CF gut microbiome. IMPORTANCE People with cystic fibrosis (pwCF) experience persistent gastrointestinal (GI) symptoms throughout life. The research question "how can we relieve gastrointestinal symptoms, such as stomach pain, bloating, and nausea?" remains a top priority for clinical research in CF. While CF transmembrane conductance regulator (CFTR) modulator therapies are understood to correct underlying issues of CF disease and increasing the numbers of pwCF are now receiving some form of CFTR modulator treatment. It is not known how these therapies affect the gut microbiome or GI system. In this pilot study, we investigated, for the first time, effects of the dual combination CFTR modulator medicine, Tezacaftor/Ivacaftor. We found it had negligible effects on patient GI symptoms, intestinal inflammation, or gut microbiome composition and functioning. Our findings are important as they fill important knowledge gaps on the relative effectiveness of these widely used treatments. We are now investigating triple combination CFTR modulators with prolonged sampling periods.
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- 2023
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33. A refresh of the top 10 research priorities in cystic fibrosis.
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Rowbotham NJ, Smith S, Elliott ZC, Cupid B, Allen LJ, Cowan K, Allen L, and Smyth AR
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- Humans, Health Priorities, Surveys and Questionnaires, Polyvinyl Alcohol, Povidone, Cystic Fibrosis therapy, Biomedical Research
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In 2018 we published the James Lind Alliance (JLA) top 10 priorities for clinical research in cystic fibrosis (CF), chosen jointly by the patient and clinical communities. These priorities have led to new research funding. To establish whether priorities have changed with novel modulator therapies, we undertook an online international update through a series of surveys and a workshop. Patients and clinicians (n=1417) chose the refreshed top 10 from 971 new research questions (suggested by patients and clinicians) and 15 questions from 2018. We are working with the international community to promote research based on these refreshed top 10 priorities., Competing Interests: Competing interests: NJR reports support from Cystic Fibrosis Trust for attending meetings. KC reports consultancy fees for facilitation services with James Lind Alliance and CF Trust. ARS reports a Vertex Pharmaceuticals Investigator Sponsored Study Award (paid to University of Nottingham) and consultancy fees for Viatris Advisory Board (paid to University of Nottingham), a patent (Camara M, Williams P, Barrett D, Halliday N, Knox A, Smyth A, Fogarty A, Barr H, Forrester D. Alkyl quinolones as biomarkers of pseudomonas aeruginosa infection and uses thereof. PubChem [Internet]. Bethesda (MD): National Library of Medicine (US), National Center for Biotechnology Information; 2004-. PubChem Patent Summary for US-2016131648-A1; [cited 2020 Nov. 17]. Available from: https://pubchem.ncbi.nlm.nih.gov/patent/US-2016131648-A1) and participation on the US CF Foundation data safety monitoring board., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.)
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- 2023
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34. Thinking outside the box: a review of gastrointestinal symptoms and complications in cystic fibrosis.
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Yule A, Sills D, Smith S, Spiller R, and Smyth AR
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- Humans, Comorbidity, Prevalence, Cystic Fibrosis complications, Cystic Fibrosis epidemiology, Cystic Fibrosis therapy, Intestinal Obstruction complications
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Introduction: Gastrointestinal (GI)-related symptoms, complications, and comorbidities in cystic fibrosis (CF) are common and research to reduce their burden is a priority for the CF community. To enable future research, this review aimed to summarize the range of GI symptoms, complications and comorbidities seen in CF, the underlying pathophysiology, and treatments., Areas Covered: This was a rapid systematic review undertaken using the recommendations from the Cochrane Rapid Reviews Methods Group. We searched databases including PubMed, Embase, Medline and the Cochrane database and identified those studies reporting GI-related symptoms, complications, or comorbidities in CF or their treatment. Our searches identified 2,930 studies and a total 119 studies met our inclusion criteria. Where a prevalence could be determined, GI symptoms were reported in 33.7% of study participants. The range of symptoms reported was broad and the highest median prevalence included flatulence (43.5%), bloating and abdominal distension (36%), and fatty stool (36%). Meconium ileus was reported in 12% and distal intestinal obstruction syndrome in 8.5., Expert Opinion: GI-related symptoms, complications, and comorbidities in CF are common. More consistent characterization and recording of these symptoms in clinical studies may help achieve the priority of reducing the burden of GI disease in CF.
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- 2023
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35. Antibiotic strategies for eradicating Pseudomonas aeruginosa in people with cystic fibrosis.
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Langton Hewer SC, Smith S, Rowbotham NJ, Yule A, and Smyth AR
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- Child, Child, Preschool, Humans, Infant, Anti-Bacterial Agents therapeutic use, Azithromycin therapeutic use, Ceftazidime therapeutic use, Ciprofloxacin therapeutic use, Colistin therapeutic use, Monobactams therapeutic use, Pseudomonas aeruginosa, Tobramycin therapeutic use, Cystic Fibrosis complications, Cystic Fibrosis drug therapy, Pseudomonas Infections drug therapy, Pseudomonas Infections complications
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Background: Respiratory tract infections with Pseudomonas aeruginosa occur in most people with cystic fibrosis (CF). Established chronic P aeruginosa infection is virtually impossible to eradicate and is associated with increased mortality and morbidity. Early infection may be easier to eradicate. This is an updated review., Objectives: Does giving antibiotics for P aeruginosa infection in people with CF at the time of new isolation improve clinical outcomes (e.g. mortality, quality of life and morbidity), eradicate P aeruginosa infection, and delay the onset of chronic infection, but without adverse effects, compared to usual treatment or an alternative antibiotic regimen? We also assessed cost-effectiveness., Search Methods: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and conference proceedings. Latest search: 24 March 2022. We searched ongoing trials registries. Latest search: 6 April 2022., Selection Criteria: We included randomised controlled trials (RCTs) of people with CF, in whom P aeruginosa had recently been isolated from respiratory secretions. We compared combinations of inhaled, oral or intravenous (IV) antibiotics with placebo, usual treatment or other antibiotic combinations. We excluded non-randomised trials and cross-over trials., Data Collection and Analysis: Two authors independently selected trials, assessed risk of bias and extracted data. We assessed the certainty of the evidence using GRADE., Main Results: We included 11 trials (1449 participants) lasting between 28 days and 27 months; some had few participants and most had relatively short follow-up periods. Antibiotics in this review are: oral - ciprofloxacin and azithromycin; inhaled - tobramycin nebuliser solution for inhalation (TNS), aztreonam lysine (AZLI) and colistin; IV - ceftazidime and tobramycin. There was generally a low risk of bias from missing data. In most trials it was difficult to blind participants and clinicians to treatment. Two trials were supported by the manufacturers of the antibiotic used. TNS versus placebo TNS may improve eradication; fewer participants were still positive for P aeruginosa at one month (odds ratio (OR) 0.06, 95% confidence interval (CI) 0.02 to 0.18; 3 trials, 89 participants; low-certainty evidence) and two months (OR 0.15, 95% CI 0.03 to 0.65; 2 trials, 38 participants). We are uncertain whether the odds of a positive culture decrease at 12 months (OR 0.02, 95% CI 0.00 to 0.67; 1 trial, 12 participants). TNS (28 days) versus TNS (56 days) One trial (88 participants) comparing 28 days to 56 days TNS treatment found duration of treatment may make little or no difference in time to next isolation (hazard ratio (HR) 0.81, 95% CI 0.37 to 1.76; low-certainty evidence). Cycled TNS versus culture-based TNS One trial (304 children, one to 12 years old) compared cycled TNS to culture-based therapy and also ciprofloxacin to placebo. We found moderate-certainty evidence of an effect favouring cycled TNS therapy (OR 0.51, 95% CI 0.31 to 0.82), although the trial publication reported age-adjusted OR and no difference between groups. Ciprofloxacin versus placebo added to cycled and culture-based TNS therapy One trial (296 participants) examined the effect of adding ciprofloxacin versus placebo to cycled and culture-based TNS therapy. There is probably no difference between ciprofloxacin and placebo in eradicating P aeruginosa (OR 0.89, 95% CI 0.55 to 1.44; moderate-certainty evidence). Ciprofloxacin and colistin versus TNS We are uncertain whether there is any difference between groups in eradication of P aeruginosa at up to six months (OR 0.43, 95% CI 0.15 to 1.23; 1 trial, 58 participants) or up to 24 months (OR 0.76, 95% CI 0.24 to 2.42; 1 trial, 47 participants); there was a low rate of short-term eradication in both groups. Ciprofloxacin plus colistin versus ciprofloxacin plus TNS One trial (223 participants) found there may be no difference in positive respiratory cultures at 16 months between ciprofloxacin with colistin versus TNS with ciprofloxacin (OR 1.28, 95% CI 0.72 to 2.29; low-certainty evidence). TNS plus azithromycin compared to TNS plus oral placebo Adding azithromycin may make no difference to the number of participants eradicating P aeruginosa after a three-month treatment phase (risk ratio (RR) 1.01, 95% CI 0.75 to 1.35; 1 trial, 91 participants; low-certainty evidence); there was also no evidence of any difference in the time to recurrence. Ciprofloxacin and colistin versus no treatment A single trial only reported one of our planned outcomes; there were no adverse effects in either group. AZLI for 14 days plus placebo for 14 days compared to AZLI for 28 days We are uncertain whether giving 14 or 28 days of AZLI makes any difference to the proportion of participants having a negative respiratory culture at 28 days (mean difference (MD) -7.50, 95% CI -24.80 to 9.80; 1 trial, 139 participants; very low-certainty evidence). Ceftazidime with IV tobramycin compared with ciprofloxacin (both regimens in conjunction with three months colistin) IV ceftazidime with tobramycin compared with ciprofloxacin may make little or no difference to eradication of P aeruginosa at three months, sustained to 15 months, provided that inhaled antibiotics are also used (RR 0.84, 95 % CI 0.65 to 1.09; P = 0.18; 1 trial, 255 participants; high-certainty evidence). The results do not support using IV antibiotics over oral therapy to eradicate P aeruginosa, based on both eradication rate and financial cost., Authors' Conclusions: We found that nebulised antibiotics, alone or with oral antibiotics, were better than no treatment for early infection with P aeruginosa. Eradication may be sustained in the short term. There is insufficient evidence to determine whether these antibiotic strategies decrease mortality or morbidity, improve quality of life, or are associated with adverse effects compared to placebo or standard treatment. Four trials comparing two active treatments have failed to show differences in rates of eradication of P aeruginosa. One large trial showed that intravenous ceftazidime with tobramycin is not superior to oral ciprofloxacin when inhaled antibiotics are also used. There is still insufficient evidence to state which antibiotic strategy should be used for the eradication of early P aeruginosa infection in CF, but there is now evidence that intravenous therapy is not superior to oral antibiotics., (Copyright © 2023 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)
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36. Complex roles of TGF-β signaling pathways in lung development and bronchopulmonary dysplasia.
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Calthorpe RJ, Poulter C, Smyth AR, Sharkey D, Bhatt J, Jenkins G, and Tatler AL
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- Infant, Infant, Newborn, Female, Humans, Pregnancy, Infant, Premature, Lung metabolism, Transforming Growth Factor beta metabolism, Signal Transduction, Bronchopulmonary Dysplasia metabolism, Premature Birth metabolism
- Abstract
As survival of extremely preterm infants continues to improve, there is also an associated increase in bronchopulmonary dysplasia (BPD), one of the most significant complications of preterm birth. BPD development is multifactorial resulting from exposure to multiple antenatal and postnatal stressors. BPD has both short-term health implications and long-term sequelae including increased respiratory, cardiovascular, and neurological morbidity. Transforming growth factor β (TGF-β) is an important signaling pathway in lung development, organ injury, and fibrosis and is implicated in the development of BPD. This review provides a detailed account on the role of TGF-β in antenatal and postnatal lung development, the effect of known risk factors for BPD on the TGF-β signaling pathway, and how medications currently in use or under development, for the prevention or treatment of BPD, affect TGF-β signaling.
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- 2023
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37. Future therapies for cystic fibrosis.
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Allen L, Allen L, Carr SB, Davies G, Downey D, Egan M, Forton JT, Gray R, Haworth C, Horsley A, Smyth AR, Southern KW, and Davies JC
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- Humans, Cystic Fibrosis Transmembrane Conductance Regulator genetics, Cystic Fibrosis Transmembrane Conductance Regulator metabolism, Mutation, Genetic Therapy, Cystic Fibrosis drug therapy, Cystic Fibrosis genetics
- Abstract
We are currently witnessing transformative change for people with cystic fibrosis with the introduction of small molecule, mutation-specific drugs capable of restoring function of the defective protein, cystic fibrosis transmembrane conductance regulator (CFTR). However, despite being a single gene disorder, there are multiple cystic fibrosis-causing genetic variants; mutation-specific drugs are not suitable for all genetic variants and also do not correct all the multisystem clinical manifestations of the disease. For many, there will remain a need for improved treatments. Those patients with gene variants responsive to CFTR modulators may have found these therapies to be transformational; research is now focusing on safely reducing the burden of symptom-directed treatment. However, modulators are not available in all parts of the globe, an issue which is further widening existing health inequalities. For patients who are not suitable for- or do not have access to- modulator drugs, alternative approaches are progressing through the trials pipeline. There will be challenges encountered in design and implementation of these trials, for which the established global CF infrastructure is a major advantage. Here, the Cystic Fibrosis National Research Strategy Group of the UK NIHR Respiratory Translational Research Collaboration looks to the future of cystic fibrosis therapies and consider priorities for future research and development., (© 2023. The Author(s).)
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38. Digital technology for monitoring adherence to inhaled therapies in people with cystic fibrosis.
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Smith S, Calthorpe R, Herbert S, and Smyth AR
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- Adult, Child, Humans, Digital Technology, Anti-Bacterial Agents therapeutic use, Administration, Inhalation, Nebulizers and Vaporizers, Quality of Life, Cystic Fibrosis complications
- Abstract
Background: Improved understanding and treatment of cystic fibrosis (CF) has led to longer life expectancy, which is accompanied by an increasingly complex regimen of treatments. Suboptimal adherence to the treatment plan, in the context of respiratory disease, has been found to be associated with poorer health outcomes. With digital technology being more accessible, it can be used to monitor adherence to inhaled therapies via chipped nebulisers, mobile phone apps and web-based platforms. This technology can allow monitoring of adherence as well as clinical outcomes, and allow feedback to both the person with CF and their healthcare team., Objectives: To assess the effects of using digital technology to monitor adherence to inhaled therapies and health status in adults and children with CF., Search Methods: We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Date of last search: 28 October 2021. We also searched Embase and three clinical trial registries and checked references of included studies. Date of last search: 9 November 2021., Selection Criteria: We searched for randomised controlled trials (RCTs) looking at the effects of a digital technology for monitoring adherence of children and adults with CF to inhaled therapies., Data Collection and Analysis: Two review authors screened the search results for studies eligible for inclusion in the review and extracted their data. We used Risk of Bias 2 for assessing study quality. We assessed the overall certainty of the evidence using GRADE., Main Results: We included two studies in our review, with 628 participants aged five to 41 years. There was one study each for two different comparisons. Nebuliser target inhalation mode versus standard inhalation mode The included parallel study was carried out over 10 weeks after a run-in period of four to six weeks. The study compared the effects of a digitally enhanced inhalation mode (target inhalation mode) for nebulised antibiotics compared to standard mode in children attending a regional CF clinic in the United Kingdom. The study's primary outcome was the time taken to complete the inhaled treatment, but investigators also reported on adherence to therapy. The results showed that there may be an improvement in adherence with the target inhalation mode when this intervention is used (mean difference (MD) 24.0%, 95% confidence interval (CI) 2.95 to 45.05; low-certainty evidence). The target inhalation mode may make little or no difference to forced expiratory volume in one second (FEV
1 ) % predicted (MD 1.00 % predicted, 95% CI -9.37 to 11.37; low-certainty evidence). The study did not report on treatment burden, quality of life (QoL) or pulmonary exacerbations. eNebuliser with digital support versus eNebuliser without support One large multicentre RCT monitored adherence via data-tracking nebulisers. The intervention group also receiving access to an online web-based platform, CFHealthHub, which offered tailored, flexible support from the study interventionist as well as access to their adherence data, educational and problem-solving information throughout the 12-month trial period. We graded all evidence as moderate certainty. Compared to usual care, the digital intervention probably improves adherence to inhaled therapy (MD 18%, 95% CI 12.90 to 23.10); probably leads to slightly reduced treatment burden (MD 5.1, 95% CI 1.79 to 8.41); and may lead to slightly improved FEV1 % predicted (MD 3.70, 95% CI -0.23 to 7.63). There is probably little or no difference in the incidence of pulmonary exacerbations or QoL between the two groups., Authors' Conclusions: Digital monitoring plus tailored support via an online platform probably improves adherence to inhaled therapies and reduces treatment burden (but without a corresponding change in QoL) in the medium term (low- and moderate-certainty evidence). In a shorter time frame, technological enhancement of inhaling antibiotics may improve adherence to treatment (low-certainty evidence). There may be little or no effect on lung function with either intervention, and online monitoring probably makes no difference to pulmonary exacerbations. Future research should assess the effect of digital technology on adherence in both children and adults. Consideration of adherence to the total treatment regimen is also important, as an improvement in adherence to inhaled therapies could come at the cost of adherence to other parts of the treatment regimen., (Copyright © 2023 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)- Published
- 2023
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39. Parenchymal lung abnormalities following hospitalisation for COVID-19 and viral pneumonitis: a systematic review and meta-analysis.
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Fabbri L, Moss S, Khan FA, Chi W, Xia J, Robinson K, Smyth AR, Jenkins G, and Stewart I
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- Adult, Humans, SARS-CoV-2, Hospitalization, Lung diagnostic imaging, COVID-19 complications, Pneumonia, Viral complications, Pneumonia, Viral therapy, Pneumonia, Viral diagnosis, Pulmonary Fibrosis diagnostic imaging, Pulmonary Fibrosis etiology
- Abstract
Introduction: Persisting respiratory symptoms in COVID-19 survivors may be related to development of pulmonary fibrosis. We assessed the proportion of chest CT scans and pulmonary function tests consistent with parenchymal lung disease in the follow-up of people hospitalised with COVID-19 and viral pneumonitis., Methods: Systematic review and random effects meta-analysis of proportions using studies of adults hospitalised with SARS-CoV-2, SARS-CoV, MERS-CoV or influenza pneumonia and followed up within 12 months. Searches performed in MEDLINE and Embase. Primary outcomes were proportion of radiological sequelae on CT scans; restrictive impairment; impaired gas transfer. Heterogeneity was explored in meta-regression., Results: Ninety-five studies (98.9% observational) were included in qualitative synthesis, 70 were suitable for meta-analysis including 60 SARS-CoV-2 studies with a median follow-up of 3 months. In SARS-CoV-2, the overall estimated proportion of inflammatory sequelae was 50% during follow-up (0.50; 95% CI 0.41 to 0.58; I
2 =95%), fibrotic sequelae were estimated in 29% (0.29; 95% CI 0.22 to 0.37; I2 =94.1%). Follow-up time was significantly associated with estimates of inflammatory sequelae (-0.036; 95% CI -0.068 to -0.004; p=0.029), associations with fibrotic sequelae did not reach significance (-0.021; 95% CI -0.051 to 0.009; p=0.176). Impaired gas transfer was estimated at 38% of lung function tests (0.38 95% CI 0.32 to 0.44; I2 =92.1%), which was greater than restrictive impairment (0.17; 95% CI 0.13 to 0.23; I2 =92.5%), neither were associated with follow-up time (p=0.207; p=0.864)., Discussion: Sequelae consistent with parenchymal lung disease were observed following COVID-19 and other viral pneumonitis. Estimates should be interpreted with caution due to high heterogeneity, differences in study casemix and initial severity., Prospero Registration Number: CRD42020183139., Competing Interests: Competing interests: GJ reports NIHR BRC salaries, studentships, professorship (RP-2017-08-ST2-014)., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)- Published
- 2023
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40. Interventions for the eradication of meticillin-resistant Staphylococcus aureus (MRSA) in people with cystic fibrosis.
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Lo DK, Muhlebach MS, and Smyth AR
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- Humans, Pseudomonas aeruginosa, Anti-Bacterial Agents therapeutic use, Rifampin therapeutic use, Methicillin-Resistant Staphylococcus aureus, Cystic Fibrosis drug therapy
- Abstract
Background: Cystic fibrosis is an inherited recessive disorder of chloride transport that is characterised by recurrent and persistent pulmonary infections from resistant organisms that result in lung function deterioration and early mortality in sufferers. Meticillin-resistant Staphylococcus aureus (MRSA) has emerged not only as an important infection in people who are hospitalised, but also as a potentially harmful pathogen in cystic fibrosis. Chronic pulmonary infection with MRSA is thought to confer on people with cystic fibrosis a worse clinical outcome and result in an increased rate of lung function decline. Clear guidance for MRSA eradication in cystic fibrosis, supported by robust evidence, is urgently needed. This is an update of a previous review., Objectives: To evaluate the effectiveness of treatment regimens designed to eradicate MRSA and to determine whether the eradication of MRSA confers better clinical and microbiological outcomes for people with cystic fibrosis. To ascertain whether attempts at eradicating MRSA can lead to increased acquisition of other resistant organisms (including Pseudomonas aeruginosa), increased adverse effects from drugs, or both., Search Methods: We identified randomised and quasi-randomised controlled trials by searching the Cochrane Cystic Fibrosis and Genetic Disorders (CFGD) Group's Cystic Fibrosis Trials Register, PubMed, MEDLINE and three clinical trials registries; by handsearching article reference lists; and through contact with experts in the field. We last searched the CFGD Group's Cystic Fibrosis Trials Register on 4 October 2021, and the ongoing trials registries on 31 January 2022., Selection Criteria: Randomised controlled trials (RCTs) or quasi-RCTs of any combinations of topical, inhaled, oral or intravenous antimicrobials primarily aimed at eradicating MRSA compared with placebo, standard treatment or no treatment., Data Collection and Analysis: We used standard methodological procedures expected by Cochrane and used the GRADE methodology to assess the certainty of the evidence., Main Results: The review includes three RCTs with 135 participants with MRSA infection. Two trials compared active treatment versus observation only and one trial compared active treatment with placebo. Active treatment versus observation In both trials (106 participants), active treatment consisted of oral trimethoprim and sulfamethoxazole combined with rifampicin. One trial administered this combination for two weeks alongside nasal, skin and oral decontamination and a three-week environmental decontamination, while the second trial administered this drug combination for 21 days with five days intranasal mupirocin. Both trials reported successful eradication of MRSA in people with cystic fibrosis, but they used different definitions of eradication. One trial (45 participants) defined MRSA eradication as negative MRSA respiratory cultures at day 28, and reported that oral trimethoprim and sulfamethoxazole combined with rifampicin may lead to a higher proportion of negative cultures compared to control (odds ratio (OR) 12.6 (95% confidence interval (CI) 2.84 to 55.84; low-certainty evidence). However, by day 168 of follow-up, there was no difference between groups in the proportion of participants who remained MRSA-negative (OR 1.17, 95% CI 0.31 to 4.42; low-certainty evidence). The second trial defined successful eradication as the absence of MRSA following treatment in at least three cultures over a period of six months. We are uncertain if the intervention led to results favouring the treatment group as the certainty of the evidence was very low (OR 2.74, 95% CI 0.64 to 11.75). There were no differences between groups in the remaining outcomes for this comparison: quality of life, frequency of exacerbations or adverse effects (all low-certainty evidence) or the change from baseline in lung function or weight (both very low-certainty evidence). The time until next positive MRSA isolate was not reported. The included trials found no differences between groups in terms of nasal colonisation with MRSA. While not a specific outcome of this review, investigators from one study reported that the rate of hospitalisation from screening through day 168 was lower with oral trimethoprim and sulfamethoxazole combined with rifampicin compared to control (rate ratio 0.22, 95% CI 0.05 to 0.72; P = 0.01). Nebulised vancomycin with oral antibiotics versus nebulised placebo with oral antibiotics The third trial (29 participants) defined eradication as a negative respiratory sample for MRSA at one month following completion of treatment. No differences were reported in MRSA eradication between treatment arms (OR 1.00, 95% CI 0.14 to 7.39; low-certainty evidence). No differences between groups were seen in lung function or adverse effects (low-certainty evidence), in quality of life (very low-certainty evidence) or nasal colonisation with MRSA. The trial did not report on the change in weight or frequency of exacerbations. AUTHORS' CONCLUSIONS: Early eradication of MRSA is possible in people with cystic fibrosis, with one trial demonstrating superiority of active MRSA treatment compared with observation only in terms of the proportion of MRSA-negative respiratory cultures at day 28. However, follow-up at three or six months showed no difference between treatment and control in the proportion of participants remaining MRSA-negative. Moreover, the longer-term clinical consequences - in terms of lung function, mortality and cost of care - remain unclear. Using GRADE methodology, we judged the certainty of the evidence provided by this review to be very low to low, due to potential biases from the open-label design, high rates of attrition and small sample sizes. Based on the available evidence, we believe that whilst early eradication of respiratory MRSA in people with cystic fibrosis is possible, there is not currently enough evidence regarding the clinical outcomes of eradication to support the use of the interventions studied., (Copyright © 2022 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)
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41. Wheeze in the time of COVID-19: overcoming obstacles to an unusual diagnosis.
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Barclay M, Buderi S, Bush A, Daniel M, Jordan S, Rice A, Ruggins N, Semple T, and Smyth AR
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- Humans, Tomography, X-Ray Computed, Bronchoscopy, Diagnosis, Differential, COVID-19 Testing, COVID-19 diagnosis, Asthma diagnosis, Pulmonary Atelectasis, Foreign Bodies diagnosis
- Abstract
This case is an example of a rare cause of a common clinical presentation (persistent lobar collapse with wheeze). We describe patient management from primary care through to a national thoracic referral centre. We highlight the importance of objective testing to support an asthma diagnosis and the need to consider alternative or additional diagnoses if a patient does not respond to treatment or the clinical course is unexpected. We highlight the importance of follow-up X-ray to determine whether atelectasis has resolved, which was significantly delayed in this case due to COVID-19 restrictions. Though rare, an endobronchial tumour should be considered if atelectasis persists and when planning endoscopy for a presumed foreign body, especially if the clinical history and patient factors make a foreign body less likely. Greater awareness of this as a differential may expedite diagnoses for patients in future. We show how virtual, multicentre, multidisciplinary meetings can aid rapid diagnosis, surgical planning and coordination of follow-up across centres., Competing Interests: Competing interests: ARS reports grants and speaker honoraria from Vertex as well as expenses and personal fees from Vertex, outside the submitted work. In addition, ARS has a patent issued 'alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof'. The other authors had no competing interests to declare., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2022
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42. Protocol for establishing a core outcome set for evaluation in studies of pulmonary exacerbations in people with cystic fibrosis.
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McLeod C, Smyth AR, Messer M, Schultz A, Wood J, Norman R, Blyth CC, Webb S, Elliott Z, Van Devanter D, Stephenson AL, Tong A, and Snelling TL
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- Adolescent, Bayes Theorem, Child, Delphi Technique, Humans, Outcome Assessment, Health Care methods, Treatment Outcome, Cystic Fibrosis complications, Cystic Fibrosis therapy, Research Design
- Abstract
Introduction: Pulmonary exacerbations are associated with increased morbidity and mortality in people with cystic fibrosis (CF). There is no consensus about which outcomes should be evaluated in studies of pulmonary exacerbations or how these outcomes should be measured. Outcomes of importance to people with lived experience of the disease are frequently omitted or inconsistently reported in studies, which limits the value of such studies for informing practice and policy. To better standardise outcome reporting and measurement, we aim to develop a core outcome set for studies of pulmonary exacerbations in people with CF (COS-PEX) and consensus recommendations for measurement of core outcomes., Methods and Analysis: Preliminary work for development of COS-PEX has been reported, including (1) systematic reviews of outcomes and methods for measurement reported in existing studies of pulmonary exacerbations; (2) workshops with people affected by CF within Australia; and (3) a Bayesian knowledge expert elicitation workshop with health professionals to ascertain outcomes of importance. Here we describe a protocol for the additional stages required for COS-PEX development and consensus methods for measurement of core outcomes. These include (1) an international two-round online Delphi survey and (2) consensus workshops to review and endorse the proposed COS-PEX and to agree with methods for measurement., Ethics and Dissemination: National mutual ethics scheme approval has been provided by the Child and Adolescent Health Service Human Research Ethics Committee (RGS 4926). Results will be disseminated via consumer and research networks and peer-reviewed publications. This study is registered with the Core Outcome Measures in Effectiveness Trials database., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2022
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43. Perspectives of patients, family members, health professionals and the public on the impact of COVID-19 on mental health.
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Gardiner E, Baumgart A, Tong A, Elliott JH, Azevedo LC, Bersten A, Cervantes L, Chew DP, Cho Y, Crowe S, Douglas IS, Evangelidis N, Flemyng E, Horby P, Howell M, Lee J, Lorca E, Lynch D, Marshall JC, Gonzalez AM, McKenzie A, Manera K, Mehta S, Mer M, Morris AC, Nseir S, Povoa P, Reid M, Sakr Y, Shen N, Smyth AR, Snelling T, Strippoli GFM, Teixeira-Pinto A, Torres A, Viecelli AK, Webb S, Williamson PR, Woc-Colburn L, Zhang J, and Craig JC
- Subjects
- Anxiety epidemiology, Anxiety psychology, Depression psychology, Family, Humans, Mental Health, SARS-CoV-2, COVID-19
- Abstract
Background: The coronavirus (COVID-19) pandemic has seen a global surge in anxiety, depression, post-traumatic stress disorder (PTSD), and stress., Aims: This study aimed to describe the perspectives of patients with COVID-19, their family, health professionals, and the general public on the impact of COVID-19 on mental health., Methods: A secondary thematic analysis was conducted using data from the COVID-19 COS project. We extracted data on the perceived causes and impact of COVID-19 on mental health from an international survey and seven online consensus workshops., Results: We identified four themes (with subthemes in parenthesis): anxiety amidst uncertainty (always on high alert, ebb and flow of recovery); anguish of a threatened future (intense frustration of a changed normality, facing loss of livelihood, trauma of ventilation, a troubling prognosis, confronting death); bearing responsibility for transmission (fear of spreading COVID-19 in public; overwhelming guilt of infecting a loved one); and suffering in isolation (severe solitude of quarantine, sick and alone, separation exacerbating grief)., Conclusion: We found that the unpredictability of COVID-19, the fear of long-term health consequences, burden of guilt, and suffering in isolation profoundly impacted mental health. Clinical and public health interventions are needed to manage the psychological consequences arising from this pandemic.
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- 2022
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44. Preferred health outcome states following treatment for pulmonary exacerbations of cystic fibrosis.
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McLeod C, Wood J, Mulrennan S, Morey S, Schultz A, Messer M, Spaapen K, Wu Y, Mascaro S, Smyth AR, Blyth CC, Webb S, Snelling TL, and Norman R
- Subjects
- Adult, Australia epidemiology, Child, Female, Humans, Lung, Male, Outcome Assessment, Health Care, Cystic Fibrosis complications, Cystic Fibrosis epidemiology, Cystic Fibrosis therapy
- Abstract
Background: Treatment for pulmonary exacerbations of cystic fibrosis (CF) can produce a range of positive and negative outcomes. Understanding which of these outcomes are achievable and desirable to people affected by disease is critical to agreeing to goals of therapy and determining endpoints for trials. The relative importance of outcomes resulting from treatment of these episodes are not reported. We aimed to (i) quantify the relative importance of outcomes resulting from treatment for pulmonary exacerbations and (ii) develop patient and proxy carer-reported weighted outcome measures for use in adults and children, respectively., Methods: A discrete choice experiment (DCE) survey was conducted. Participants were asked to make a series of hypothetical decisions about treatment for pulmonary exacerbations to assess how they make trade-offs between different attributes of health. Data were analysed using a conditional logistic regression model. The correlation coefficients from these data were rescaled to enable generation of a composite health outcome score between 0 and 100 (worst to best health state)., Results: 362 individuals participated (167 people with CF and 195 carers); of these, 206 completed the survey (56.9%). Most participants were female and resided in Australia. Difficult/painful breathing had the greatest impact on the preferred health state amongst people with CF and carers alike. Avoidance of gastrointestinal problems also heavily influenced decision-making., Conclusions: These data should be considered when making treatment decisions and determining endpoints for trials. Further research is recommended to quantify the preferences of children and to determine whether these align with those of their carer(s)., Competing Interests: Declaration of Competing Interest ASm reports grants from Vertex, as well as speaker honoraria and expenses from Vertex and Teva, outside the submitted work. In addition, ASm has a patent issued “Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof”. Other authors have no conflicts of interest to declare., (Copyright © 2021. Published by Elsevier B.V.)
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- 2022
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45. Novel detection of specific bacterial quorum sensing molecules in saliva: Potential non-invasive biomarkers for pulmonary Pseudomonas aeruginosa in cystic fibrosis.
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Webb K, Cámara M, Zain NMM, Halliday N, Bruce KD, Nash EF, Whitehouse JL, Knox A, Forrester D, Smyth AR, Williams P, Fogarty A, and Barr HL
- Subjects
- Adult, Biomarkers analysis, Humans, Lung microbiology, Pseudomonas aeruginosa, Quorum Sensing, Saliva chemistry, Sputum microbiology, Cystic Fibrosis diagnosis, Cystic Fibrosis microbiology, Pseudomonas Infections diagnosis, Pseudomonas Infections microbiology
- Abstract
Pseudomonas aeruginosa produces specific signalling molecules, 2-alkyl-4-quinolones (AQs) that are detectable in the sputum of adults with cystic fibrosis (CF) and who have pulmonary infection with this opportunistic pathogen. This study aimed to determine whether AQs could be detected in saliva of patients with CF and known infection with Pseudomonas aeruginosa. Saliva and sputum samples were obtained from 89 adults with CF and analyzed using liquid chromatography-tandem mass spectrometry. AQs were detected in 39/89 (43.8%) saliva samples and 70/77(90.9%) sputum samples. Salivary AQs had a sensitivity of 50% (95%CI; 37.8; 62.2), specificity of 100% (95%CI; 47.8; 100), when compared to a molecular microbiological measure of P. aeruginosa in sputum as measured using polymerase chain reaction. Specific AQs produced by P. aeruginosa can be detected in the saliva and warrant investigation as potential non-invasive biomarkers of pulmonary P. aeruginosa., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)
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- 2022
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46. Industry influence in healthcare harms patients: myth or maxim?
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Trayer J, Rowbotham NJ, Boyle RJ, and Smyth AR
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Healthcare is a major global industry accounting for a significant proportion of government spending. Drug and medical device manufacturers are publicly traded companies with a responsibility to their shareholders to maximise profits by increasing sales. In order to achieve this, industry exerts influence over every part of healthcare including academic research, medical education, clinical guideline development, physician prescribing and through direct interactions with patients. In contrast, healthcare services seek to provide effective, safe and evidence-based treatments. This article examines interactions with industry across these domains and seeks to identify mutually beneficial relationships and potential conflict leading to patient harms. Case studies are used to illustrate these interactions. There is no single solution for improving healthcare's relationship with industry, although increased transparency has raised awareness of this issue. We briefly discuss some successful interventions that have been tried at national and regulatory level. While industry influence is widespread in healthcare and this has benefits for shareholders, healthcare practitioners have an ethical obligation to prioritise their patients' best interests. Industry interactions with healthcare professionals have a valid role in product development and distribution, but industry sponsorship of healthcare education and practice, guideline development or regulatory decision-making can have harmful consequences for patients. Healthcare practitioners need to carefully consider these issues when deciding whether to collaborate with industry., Educational Aims: To explore the many areas where industry influences healthcare and the subsequent effects on patient care. Case studies are used to illustrate examples of beneficial and harmful effects of this influence.To raise awareness of the effects of industry influence and for readers to consider their own potential conflicts of interest.To suggest potential ways to improve the current system with a focus on solutions which have successfully been trialled already., Competing Interests: Conflict of interest: A.R. Smyth has received grants or contracts from Vertex Pharmaceuticals; payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing or educational events from Vertex Pharmaceuticals; and support for attending meetings and/or travel from Vertex Pharmaceuticals, all outside the submitted work. A.R. Smyth has patents planned, issued or pending (Camara M, Williams P, Barrett D, Halliday N, Knox A, Smyth A, Fogarty A, Barr H, Forrester D. Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof (US-2016131648-A1; https://pubchem.ncbi.nlm.nih.gov/patent/US-2016131648-A1)), outside the submitted work. A.R. Smyth reports participation on a Data Safety Monitoring Board or Advisory Board for North American Cystic Fibrosis Foundation Therapeutic Development Network Data Safety Monitoring Board, outside the submitted work. R.J. Boyle has received consulting fees from Cochrane, John Wiley and Sons, British Society for Allergy and Clinical Immunology, and Prota Therapeutics, outside the submitted work; and has received payment for expert testimony from Taus and Cebulash, outside the submitted work. The remaining authors have nothing to disclose., (Copyright ©ERS 2022.)
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47. Intestinal function and transit associate with gut microbiota dysbiosis in cystic fibrosis.
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Marsh R, Gavillet H, Hanson L, Ng C, Mitchell-Whyte M, Major G, Smyth AR, Rivett D, and van der Gast C
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- Dysbiosis etiology, Feces microbiology, Humans, Pilot Projects, RNA, Ribosomal, 16S genetics, Cystic Fibrosis, Gastrointestinal Microbiome physiology
- Abstract
Background: Most people with cystic fibrosis (pwCF) suffer from gastrointestinal symptoms and are at risk of gut complications. Gut microbiota dysbiosis is apparent within the CF population across all age groups, with evidence linking dysbiosis to intestinal inflammation and other markers of health. This pilot study aimed to investigate the potential relationships between the gut microbiota and gastrointestinal physiology, transit, and health., Study Design: Faecal samples from 10 pwCF and matched controls were subject to 16S rRNA sequencing. Results were combined with clinical metadata and MRI metrics of gut function to investigate relationships., Results: pwCF had significantly reduced microbiota diversity compared to controls. Microbiota compositions were significantly different, suggesting remodelling of core and rarer satellite taxa in CF. Dissimilarity between groups was driven by a variety of taxa, including Escherichia coli, Bacteroides spp., Clostridium spp., and Faecalibacterium prausnitzii. The core taxa were explained primarily by CF disease, whilst the satellite taxa were associated with pulmonary antibiotic usage, CF disease, and gut function metrics. Species-specific ordination biplots revealed relationships between taxa and the clinical or MRI-based variables observed., Conclusions: Alterations in gut function and transit resultant of CF disease are associated with the gut microbiota composition, notably the satellite taxa. Delayed transit in the small intestine might allow for the expansion of satellite taxa resulting in potential downstream consequences for core community function in the colon., Competing Interests: Declaration of Competing Interest RJM, HG, LH, DM, and CvdG declare support from the CF Trust. CN and GM report grants and speaker honorarium from Vertex, outside the submitted work. ARS reports grants from Vertex, as well as speaker honoraria and expenses from Teva and Novartis and personal fees from Vertex, outside the submitted work. In addition, ARS has a patent issued “Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof”., (Copyright © 2021. Published by Elsevier B.V.)
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- 2022
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48. Magnetic resonance imaging of the gastrointestinal tract shows reduced small bowel motility and altered chyme in cystic fibrosis compared to controls.
- Author
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Dellschaft NS, Ng C, Hoad C, Marciani L, Spiller R, Stewart I, Menys A, Barr H, Gowland PA, Major G, and Smyth AR
- Subjects
- Gastrointestinal Motility, Gastrointestinal Tract, Gastrointestinal Transit, Humans, Magnetic Resonance Imaging, Cystic Fibrosis
- Abstract
People with cystic fibrosis (CF) experience digestive symptoms but the mechanisms are incompletely understood. Here we explore causes and consequences of slower gastrointestinal transit using magnetic resonance imaging (MRI). Twelve people with CF and 12 healthy controls, matched for age and gender, underwent MRI scans, both fasted and after standardised meals, over 6.5 h. Fasted small bowel motility scores were lower in CF than in controls. No difference in ascending colon chyme T
1 was detected. The difference in texture between small bowel and colon contents, seen in health, was diminished in CF. The ascending colon in CF participants had an abnormal appearance compared to controls. MRI offers unique potential to evaluate gut luminal content, colonic mucosa and intestinal motor activity. These new data support the theoretical cycle of desiccation, dysmotility and delayed transit as a cause of gastrointestinal symptoms in CF., Competing Interests: Declaration of Competing Interest ND, CH, LM, HB, IS & PG have nothing to disclose. CN and GM report grants and speaker honorarium from Vertex, outside the submitted work. RS reports grants from Zespri International Ltd and Sanofi- Aventis, as well as lecturing fees from Menarini and Alfawasserman, outside the submitted work. AM is the CEO of Motilent Limited, a medical imaging analysis company. AS reports grants from Vertex, as well as speaker honoraria and expenses from Teva and Vertex, outside the submitted work. In addition, AS has a patent issued “Alkyl quinolones as biomarkers of Pseudomonas aeruginosa infection and uses thereof”., (Copyright © 2021 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)- Published
- 2022
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49. Exploring the challenges of accessing medication for patients with cystic fibrosis.
- Author
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Herbert S, Rowbotham NJ, Smith S, Wilson P, Elliott ZC, Leighton PA, Duff A, and Smyth AR
- Subjects
- Humans, Pharmacists, Surveys and Questionnaires, Cystic Fibrosis therapy
- Abstract
Reducing treatment burden in cystic fibrosis (CF) is the top research priority for patients and clinicians. Difficulty accessing medication is one aspect of treatment burden. We investigated this with an online survey available globally for patients with CF and healthcare professionals. Almost three quarters of patients with CF in our survey report difficulty getting repeat prescriptions on time, and most community pharmacists experience interrupted supplies of CF-specific medications. These barriers affect emotional and physical health of people with CF. Two-thirds of people with CF would like to get all their CF medication from one place, their CF centre., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2022
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50. Wind induced algal migration manipulates sediment denitrification N-loss patterns in shallow Taihu Lake, China.
- Author
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Shi W, Zhu L, Van Dam B, Smyth AR, Deng J, Zhou J, Pan G, Yi Q, Yu J, and Qin B
- Abstract
Driven by winds, the distribution of algae is often noticeably patchy at kilometer scales in shallow lakes. The decomposition of the settled algal biomass may affect nitrogen (N) biogeochemical cycles and thereby N loss in sediments. In this study, we investigated sediment denitrification N-loss patterns along algal migration pathway in Taihu Lake, a shallow and eutrophic lake in China, and found that wind-induced algal migration in the overlying water manipulated the temporal and spatial patterns of denitrification N-loss in sediments. A N loss hotspot in sediments was created in the algae concentrated zone, where N loss was, however, temporarily inhibited during algal bloom seasons and generally exhibited a negative relationship with algal biomass. In the zone where algae have left, sediment N loss rate was relatively low and positively correlated with algal biomass. The decay of algal biomass generated organic carbon and created anoxia, favoring denitrification, while excessive algal biomass could deplete oxygen and inhibit nitrification, causing nitrate limitation for denitrification. Piecewise linear regression analysis indicated that algal biomass of Chl-a > 73.0 μg/L in the overlying water could inhibit denitrification N-loss in sediments. This study adds to our understanding of N biogeochemical cycles in shallow eutrophic lakes., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
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