28 results on '"Retsch-Bogart GZ"'
Search Results
2. Update on new pulmonary therapies.
- Author
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Retsch-Bogart GZ and Retsch-Bogart, George Z
- Published
- 2009
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3. Inhaled aztreonam lysine for chronic airway Pseudomonas aeruginosa in cystic fibrosis.
- Author
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McCoy KS, Quittner AL, Oermann CM, Gibson RL, Retsch-Bogart GZ, Montgomery AB, McCoy, Karen S, Quittner, Alexandra L, Oermann, Christopher M, Gibson, Ronald L, Retsch-Bogart, George Z, and Montgomery, A Bruce
- Abstract
Rationale: The effectiveness and safety of aztreonam lysine for inhalation (AZLI) in patients with cystic fibrosis (CF) on maintenance treatment for Pseudomonas aeruginosa (PA) airway infection was evaluated in this randomized, double-blind, placebo-controlled study.Objectives: To evaluate the safety and efficacy of inhaled aztreonam lysine in controlling PA infection in patients with CF.Methods: After randomization and a 28-day course of tobramycin inhalation solution (TIS), patients (n = 211; > or =6 yr; > or =3 TIS courses within previous year; FEV(1) > or = 25% and < or =75% predicted values) were treated with 75 mg AZLI or placebo, twice or three times daily for 28 days, then monitored for 56 days. The primary efficacy endpoint was time to need for additional inhaled or intravenous antipseudomonal antibiotics. Secondary endpoints included changes in respiratory symptoms (CF Questionnaire-Revised [CFQ-R] Respiratory Scale), pulmonary function (FEV(1)), and sputum PA density. Adverse events and minimum inhibitory concentrations of aztreonam for PA were monitored.Measurements and Main Results: AZLI treatment increased median time to need for additional antipseudomonal antibiotics for symptoms of pulmonary exacerbation by 21 days, compared with placebo (AZLI, 92 d; placebo, 71 d; P = 0.007). AZLI improved mean CFQ-R respiratory scores (5.01 points, P = 0.02), FEV(1) (6.3%, P = 0.001), and sputum PA density (-0.66 log(10) cfu/g, P = 0.006) compared with placebo; no AZLI dose-response was observed. Adverse events reported for AZLI and placebo were comparable and consistent with CF lung disease. Susceptibility of PA to aztreonam at baseline and end of therapy were similar.Conclusions: AZLI was effective in patients with CF using frequent TIS therapy. AZLI delayed time to need for inhaled or intravenous antipseudomonal antibiotics, improved respiratory symptoms and pulmonary function, and was well tolerated. Clinical trial registered with www.clinicaltrials.gov (NCT 00104520). [ABSTRACT FROM AUTHOR]- Published
- 2008
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4. Computed tomography reflects lower airway inflammation and tracks changes in early cystic fibrosis.
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Davis SD, Fordham LA, Brody AS, Noah TL, Retsch-Bogart GZ, Qaqish BF, Yankaskas BC, Johnson RC, Leigh MW, Davis, Stephanie D, Fordham, Lynn A, Brody, Alan S, Noah, Terry L, Retsch-Bogart, George Z, Qaqish, Bahjat F, Yankaskas, Bonnie C, Johnson, Robin C, and Leigh, Margaret W
- Abstract
Rationale: Detecting and tracking early cystic fibrosis (CF) lung disease are difficult due to lack of sensitive markers of airway dysfunction.Objectives: The goals were to detect regional distribution of airway disease through high-resolution computed tomography, correlate abnormalities to lower airway inflammation/infection, and compare computed tomography findings before and after intravenous antibiotic therapy in children with CF younger than 4 years experiencing a pulmonary exacerbation.Methods: High-resolution computed tomography was performed in 17 children scheduled for bronchoscopy. The radiologist identified the lobes with the "greatest" and "least" disease based on computed tomography, and bronchoalveolar lavage was performed in these areas. In 13 subjects, imaging was repeated after antibiotic completion. Modified Brody scores were assigned by two radiologists.Measurements and Main Results: The lobe with greatest disease was predominantly localized to the right and had higher modified Brody scores, indicating more severe abnormalities (p < 0.01), compared with the lobe with least disease. The total modified Brody score (p < 0.01), hyperinflation subscore (p < 0.01), and bronchial dilatation/bronchiectasis subscore (p < 0.01) improved after antibiotics and intensified airway clearance. Interleukin-8 levels (p < 0.01) and % neutrophils (p = 0.04) were increased in the lobe with greatest disease compared with the lobe with least disease.Conclusions: These results indicate that, in young children with CF experiencing a pulmonary exacerbation, computed tomography detects regional differences in airway inflammation, may be a sensitive outcome to evaluate therapeutic interventions, and identifies early lung disease as being more prominent on the right. [ABSTRACT FROM AUTHOR]- Published
- 2007
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5. Inflammatory and microbiologic markers in induced sputum after intravenous antibiotics in cystic fibrosis.
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Ordoñez CL, Henig NR, Mayer-Hamblett N, Accurso FJ, Burns JL, Chmiel JF, Daines CL, Gibson RL, McNamara S, Retsch-Bogart GZ, Zeitlin PL, and Aitken ML
- Abstract
Induced sputum has been used to study airway inflammation. We sought to determine whether markers of infection and inflammation in induced sputum were a useful and safe outcome measure in cystic fibrosis. We hypothesized that bacterial density and inflammatory content of induced sputum would decrease after antibiotic therapy. Induced sputum was assayed for bacterial density, cell count, and differential and inflammatory markers before and after treatment with intravenous antibiotics. Fifty-five of the 72 subjects enrolled (mean age +/- SD 18.2 +/- 7.9 years) completed the study. FEV1 increased by an average 0.3 +/- 0.3 L (10.4 +/- 8.7% predicted FEV1), p<0.0001; density of Pseudomonas aeruginosa and Staphylococcus aureus decreased by 2.4 +/- 3.1 log10 cfu/g (p<0.0005) and 4.0 +/- 2.3 log10 cfu/ml (p<0.0001), respectively; neutrophil count decreased by 0.4 +/- 0.6 log10 cells/ml (p<0.0001), interleukin-8 concentration by 0.5 +/- 1.3 log10 pg/ml (p<0.05), and neutrophil elastase by 0.4 +/- 0.7 log10 microg/ml (p<0.005). Seven of 127 (6%) sputum induction procedures showed a decrease in FEV1 of 20% or more. We conclude that markers in induced sputum may be useful, noninvasive outcome measures to assess response to therapies in cystic fibrosis studies. [ABSTRACT FROM AUTHOR]
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- 2003
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6. Impact of azithromycin on serum inflammatory markers in children with cystic fibrosis and new Pseudomonas.
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Pittman JE, Skalland MS, Sagel SD, Ramsey BW, Mayer-Hamblett N, and Retsch-Bogart GZ
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- Child, Humans, Anti-Bacterial Agents, Biomarkers, C-Reactive Protein, Leukocyte L1 Antigen Complex, Peroxidase therapeutic use, Pseudomonas, Azithromycin, Cystic Fibrosis drug therapy
- Abstract
Chronic azithromycin improves outcomes in cystic fibrosis (CF), but its mechanism of action is unclear. The OPTIMIZE trial demonstrated improvement in time to first pulmonary exacerbation in children with new Pseudomonas treated with azithromycin. Azithromycin effect on systemic markers of inflammation over 18 months was assessed by change from baseline for high-sensitivity C-reactive protein, myeloperoxidase, calprotectin and absolute neutrophil count in the OPTIMIZE population. Subjects treated with chronic azithromycin or placebo had samples collected at baseline, 39 and 78 weeks of treatment. In 129 subjects, a significant decrease in high-sensitivity C-reactive protein was present at 39 weeks in the azithromycin group compared to placebo, but no significant difference between the groups at 78 weeks. No differences in change from baseline in myeloperoxidase, calprotectin or absolute neutrophil count were present at either time point. This supports the concept of a transient immunomodulatory effect for chronic azithromycin therapy in children with CF., Competing Interests: Declaration of Competing Interests 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. The authors declare no competing interests., (Copyright © 2022. Published by Elsevier B.V.)
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- 2022
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7. A new path for CF clinical trials through the use of historical controls.
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Magaret AS, Warden M, Simon N, Heltshe S, Retsch-Bogart GZ, Ramsey BW, and Mayer-Hamblett N
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- Anti-Bacterial Agents, Azithromycin therapeutic use, Child, Humans, Lung, Cystic Fibrosis complications, Cystic Fibrosis drug therapy, Pseudomonas Infections drug therapy
- Abstract
Background: Given future challenges in conducting large randomized, placebo controlled trials for future CF therapeutics development, we evaluated the potential for using external historical controls to either enrich or replace traditional concurrent placebo groups in CF trials., Methods: The study included data from sequentially completed, randomized, controlled clinical trials, EPIC and OPTIMIZE respectively, evaluating optimal antibiotic therapy to reduce the risk of pulmonary exacerbation in children with early Pseudomonas aeruginosa infection. The primary treatment effect in OPTIMIZE, the risk of pulmonary exacerbation associated with azithromycin, was re-estimated in alternative designs incorporating varying numbers of participants from the earlier trial (EPIC) as historical controls. Bias and precision of these estimates were characterized. Propensity scores were derived to adjust for baseline differences across study populations, and both Poisson and Cox regression were used to estimate treatment efficacy., Results: Replacing 86 OPTIMIZE placebo participants with 304 controls from EPIC to mimic a fully historically controlled trial resulted an 8% reduction in risk of pulmonary exacerbations (Hazard ratio (HR):0.92 95% CI 0.61, 1.34) when not adjusting for key baseline differences between study populations. After adjustment, a 37% decrease in risk of exacerbation (HR:0.63, 95% CI 0.50, 0.80) was estimated, comparable to the estimate from the original trial comparing the 86 placebo participants to 77 azithromycin participants on azithromycin (45%, HR:0.55, 95% CI: 0.34, 0.86). Other adjusted approaches provided similar estimates for the efficacy of azithromycin in reducing exacerbation risk: pooling all controls from both studies provided a HR of 0.60 (95% x`CI 0.46, 0.77) and augmenting half the OPTIMIZE placebo participants with EPIC controls gave a HR 0.63 (95% CI 0.48, 0.82)., Conclusions: The potential exists for future CF trials to utilize historical control data. Careful consideration of both the comparability of controls and of optimal methods can reduce the potential for biased estimation of treatment effects., Competing Interests: Conflict of Interest ASM, MW and GZRB received funding from the NIH during the conduct of this research. GZRB additionally received funding from the Cystic Fibrosis Foundation. BWR has received personal fees from Cystetic Medicines and Vetex Pharmaceuticals for serving as a member of Scientific Advisory Committees., (Copyright © 2021 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)
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- 2022
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8. The impact of SARS-CoV-2 on the cystic fibrosis foundation therapeutics development network.
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Pearson K, Mayer-Hamblett N, Goss CH, Retsch-Bogart GZ, VanDalfsen JM, Burks P, Rosenbluth D, Clancy JP, Hoffman A, and Nichols DP
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- COVID-19 prevention & control, COVID-19 transmission, Foundations, Humans, Research Design, Spirometry, Surveys and Questionnaires, Biomedical Research organization & administration, COVID-19 epidemiology, Cystic Fibrosis therapy
- Abstract
The Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) global pandemic significantly impacted CF clinical research within the Cystic Fibrosis Foundation Therapeutics Development Network (CFF TDN). A Research Electronic Data Capture (REDCap) survey was developed and sent to network sites to monitor and understand the impact on research teams, ongoing and anticipated clinical research, and specific clinical and research procedures. Key findings indicated an early impact on participant enrollment, research team stability, and procedures such as spirometry and sputum induction. These trends steadily improved over the months as research activities began to recover across the TDN. While SARS-CoV-2 created a significant challenge it also highlights new opportunities to expand CF research with greater focus on data collection outside of research centers and increased access for remote participation., Competing Interests: Declaration of Competing Interest NMH has received grant funding from the Cystic Fibrosis Foundation (CFF) and National Institutes of Health (NIH). CHG reports grant funding from CFF, European Commission, National Heart, Lung, and Blood Institute, National Institute of Diabetes and Digestive and Kidney Diseases, National Center for Research Resources, Gilead Sciences, Novartis, NIH, Food and Drug Administration, Boehringer Ingelheim, Vertex Pharmaceuticals. None of the work presented in this short communication was influenced by the funding sources reported by CHG. KP, GZRB, JMVD, PB, DR., JPC, AH, and DPN have nothing to disclose related to this work., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
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9. Building global development strategies for cf therapeutics during a transitional cftr modulator era.
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Mayer-Hamblett N, van Koningsbruggen-Rietschel S, Nichols DP, VanDevanter DR, Davies JC, Lee T, Durmowicz AG, Ratjen F, Konstan MW, Pearson K, Bell SC, Clancy JP, Taylor-Cousar JL, De Boeck K, Donaldson SH, Downey DG, Flume PA, Drevinek P, Goss CH, Fajac I, Magaret AS, Quon BS, Singleton SM, VanDalfsen JM, and Retsch-Bogart GZ
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- Cystic Fibrosis genetics, Humans, Cystic Fibrosis drug therapy, Cystic Fibrosis Transmembrane Conductance Regulator drug effects, Drug Development organization & administration, International Cooperation
- Abstract
As CFTR modulator therapy transforms the landscape of cystic fibrosis (CF) care, its lack of uniform access across the globe combined with the shift towards a new standard of care creates unique challenges for the development of future CF therapies. The advancement of a full and promising CF therapeutics pipeline remains a necessary priority to ensure maximal clinical benefits for all people with CF. It is through collaboration across the global CF community that we can optimize the evaluation and approval process of new therapies. To this end, we must identify areas for which harmonization is lacking and for which efficiencies can be gained to promote ethical, feasible, and credible study designs amidst the changing CF care landscape. This article summarizes the counsel from core advisors across multiple international regions and clinical trial networks, developed during a one-day workshop in October 2019. The goal of the workshop was to identify, in consideration of the highly transitional era of CFTR modulator availability, the drug development areas for which global alignment is currently uncertain, and paths forward that will enable advancement of CF therapeutic development., Competing Interests: Declaration of Competing Interest NMH serves as a consultant through her institution in her role as Executive Director of the CF Therapeutics Development Network Coordinating Center (CF TDNCC) and has received personal consulting fees from Kala Pharmaceuticals and Calithera. She has received grant funding from the Cystic Fibrosis Foundation (CFF) and National Institutes of Health (NIH). SvKR has received personal consulting fees from Antabio, Proteostasis Therapeutics (PTI), and Vertex Pharmaceuticals (VRTX). She has received grant support to her institution for her participation in the European Union HORIZON 2020 work. DPN serves as a consultant through his institution in his role as Medical Director of CF TDNCC. He has received grant support to his Institution from the CFF and Gilead Sciences. DRV has received personal consulting fees from AbbVie, Albumedix, AN2, Aradigm, Armata, Arrevus, Calithera, Chiesi USA, Cipla, Corbus, CFF, Eloxx, Enbiotix, Eveo, Galephar, Horizon, IBF, ICON clinical sciences, Ionis, Kala, Merck, Microbion, NDA, Protalix, PTC, Pulmocide, Recida, Savara, Vast, and VRTX. JCD has received other support from Aligipharma AS, Bayer AG, BI, Galapagos NV, ImevaX GmbH, Nivalis Therapeutics, ProQR Therapeutics, PTI, Raptor Pharamceuticals, VRTX, Enterprise, Novartis, Pulmocide, Flately and Teva for advisory board and educational activities. She has received grant support from the CF Trust. TL has received personal fees from Alan Boyd Consultants, Ltd for his participation in DSMB activities. FAR has received personal consulting fees from Novartis, Bayer, Roche, and Genentech for participation in CF related consulting activities. He has received grant support to his institution from VRTX for his participation as site PI in multicenter trials which they have funded as well as personal consulting fees. MWK has received personal consulting fees for advisory board participation, grant support to his institution for clinical trial participation, and non-financial support from VRTX, Savara, Laurent, Corbus Pharmaceuticals, PTC, and AzurRx. He has received personal consulting fees and non-financial support from Chiesi, Celtaxsys, Merck, and Kala. Personal consulting fees were received from Albumedix, Paranta, Protalix, Santhera, pH Pharma, Novartis, Ionis, the Italian Cystic Fibrosis Foundation, and the Food and Drug Administration. Grant support was provided to his Institution by NIH. Grant support was provided to his Institution by Anthera as well as personal consulting fees. SCB has received support from VRTX, Galapagos, and AbbVie for his participation in advisory boards and as site PI in multicenter trials which they have funded. JLTC has received personal consulting fees from Gilead Sciences, Protalix, and Santhera for participation in advisory board activities. She has received grant support to her institution from PTI, Celtaxsys, and VRTX as well as personal consulting fees for advisory activities. Grant support to her institution for her participation as site PI in a multicenter trial which they have funded from Eloxx. KDB has received consulting fees from Boehringer-Ingelheim (BI), Protalix Biotherapeutics, Raptor Pharmaceuticals, Novabiotics, Eloxx Pharmaceutics, Galapagos, and Chiesi. She has received speaker fees from Teva Pharmaceutical Industries and serves on the Steering Committee and Advisory Board for VRTX. DGD has received consulting fees from VRTX and consulting fees as well as grant support from PTI and Chiesi. PAF has received personal consulting fees from the Food and Drug Administration, Polyphor, and Santhera. He has received personal consulting fees and grant support from CFF, PTI, Savara, and VRTX. He has received grant support from NIH, Novartis, Novoteris, and Sound Pharmaceuticals. PD has received personal consulting fees from VRTX, PTI, and Actelion Pharmaceuticals. He has also received support for his participation as site PI in multicenter trials funded by Corbus Pharmaceuticals and VRTX. CHG has received grant funding from CFF, NIH, the European Commission and the Food and Drug Administration. He has also received honoraria from Gilead Sciences for grant reviews, honoraria from VRTX and Mylan for invited talks, and BI for participation as a PI in a multicenter trial in CF that they have funded. IF has received consulting fees and support from PTI, VRTX and BI for her participation in advisory boards as well as site PI in multicenter trials which they have funded. She has received support from Corbus Pharmaceuticals for participation as site PI in multicenter trials which they have funded ASM has received grant support to her Institution from CFF. BSQ has received grant support to his institution from the Cystic Fibrosis Canada, CFF, Michael Smith Foundation for Health Research, BC Lung Association, and Gilead Sciences. GZRB's institution has received support from the CFF, NIH and VRTX. for his participation as site PI in multicenter trials which they have funded. AGD, KP, JPC, SHD, SMS, and JMVD have nothing to disclose., (Copyright © 2020. Published by Elsevier B.V.)
- Published
- 2020
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10. Worsening anxiety and depression after initiation of lumacaftor/ivacaftor combination therapy in adolescent females with cystic fibrosis.
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McKinzie CJ, Goralski JL, Noah TL, Retsch-Bogart GZ, and Prieur MB
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- Adolescent, Child, Drug Combinations, Female, Humans, Membrane Transport Modulators administration & dosage, Membrane Transport Modulators adverse effects, Suicidal Ideation, Withholding Treatment, Aminophenols administration & dosage, Aminophenols adverse effects, Aminopyridines administration & dosage, Aminopyridines adverse effects, Antidepressive Agents administration & dosage, Anxiety chemically induced, Anxiety diagnosis, Anxiety drug therapy, Benzodioxoles administration & dosage, Benzodioxoles adverse effects, Cognitive Behavioral Therapy methods, Cystic Fibrosis drug therapy, Cystic Fibrosis psychology, Depression chemically induced, Depression diagnosis, Depression drug therapy, Quinolones administration & dosage, Quinolones adverse effects, Suicide, Attempted prevention & control
- Abstract
In both phase III studies of LUM/IVA, as well as an extension study, worsening of mental health was not reported as a common side effect. Here we describe five cases in adolescent female patients that suggest a worsening of anxiety or depression associated with its use. In these five patients, two experienced suicidal ideation and three made suicide attempts that resulted in psychiatric hospitalizations., (Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
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11. Continuous alternating inhaled antibiotics for chronic pseudomonal infection in cystic fibrosis.
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Flume PA, Clancy JP, Retsch-Bogart GZ, Tullis DE, Bresnik M, Derchak PA, Lewis SA, and Ramsey BW
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- Administration, Inhalation, Adolescent, Adult, Anti-Bacterial Agents administration & dosage, Chronic Disease, Double-Blind Method, Female, Forced Expiratory Volume drug effects, Humans, Male, Medication Therapy Management, Time Factors, Treatment Outcome, Aztreonam administration & dosage, Cystic Fibrosis diagnosis, Cystic Fibrosis drug therapy, Pseudomonas Infections diagnosis, Pseudomonas Infections drug therapy, Pseudomonas aeruginosa isolation & purification, Respiratory Tract Infections diagnosis, Respiratory Tract Infections drug therapy, Tobramycin administration & dosage
- Abstract
Background: Inhaled antibiotics are standard of care for treating chronic pseudomonal respiratory infections in cystic fibrosis patients, initially approved for intermittent administration. However, use of continuous inhaled antibiotic regimens of differing combinations is growing., Methods: This double-blind trial compared continuous alternating therapy (CAT) to an intermittent treatment regimen. Subjects were treated with 3cycles of 28-days inhaled aztreonam (AZLI) or placebo 3-times daily alternating with 28-days open-label tobramycin inhalation solution (TIS)., Results: 90 subjects were randomized over 18months. Study enrollment was limited, in part because of evolving practices by clinicians of adopting a CAT regimen in clinical practice; consequently the study was underpowered. AZLI/TIS treatment reduced exacerbation rates by 25.7% (p=0.25; primary endpoint) and rates of respiratory hospitalizations by 35.8% compared with placebo/TIS (p=0.14). AZLI/TIS CAT therapy was well tolerated., Conclusions: This trial illustrates challenges with studying treatment regimens in a constantly evolving CF care environment. Nonetheless, the results of this trial indicate that AZLI/TIS CAT is well tolerated and may provide additional clinical benefit in CF patients compared with intermittent use of TIS alone. Clinicaltrials.gov: NCT01641822., (Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)
- Published
- 2016
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12. A Multidisciplinary Children's Airway Center: Impact on the Care of Patients With Tracheostomy.
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Abode KA, Drake AF, Zdanski CJ, Retsch-Bogart GZ, Gee AB, and Noah TL
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- Adolescent, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Length of Stay statistics & numerical data, Male, Outcome and Process Assessment, Health Care, Patient Discharge standards, Postoperative Complications prevention & control, Professional-Family Relations, Program Evaluation, Young Adult, Hospital Units organization & administration, Interdisciplinary Communication, Patient Care Team organization & administration, Quality Improvement organization & administration, Tracheostomy
- Abstract
Background: Children with complex airway problems see multiple specialists. To improve outcomes and coordinate care, we developed a multidisciplinary Children's Airway Center. For children with tracheostomies, aspects of care targeted for improvement included optimizing initial hospital discharge, promoting effective communication between providers and caregivers, and avoiding tracheostomy complications., Methods: The population includes children up to 21 years old with tracheostomies. The airway center team includes providers from pediatric pulmonology, pediatric otolaryngology/head and neck surgery, and pediatric gastroenterology. Improvement initiatives included enhanced educational strategies, weekly care conferences, institutional consensus guidelines and care plans, personalized clinic schedules, and standardized intervals between airway examinations. A patient database allowed for tracking outcomes over time., Results: We initially identified 173 airway center patients including 123 with tracheostomies. The median number of new patients evaluated by the center team each year was 172. Median hospitalization after tracheostomy decreased from 37 days to 26 days for new tracheostomy patients <1 year old discharged from the hospital. A median of 24 care plans was evaluated at weekly conferences. Consensus protocol adherence increased likelihood of successful decannulation from 68% to 86% of attempts. The median interval of 8 months between airway examinations aligned with published recommendations., Conclusions: For children with tracheostomies, our Children's Airway Center met and sustained goals of optimizing hospitalization, promoting communication, and avoiding tracheostomy complications by initiating targeted improvements in a multidisciplinary team setting. A multidisciplinary approach to management of these patients can yield measurable improvements in important outcomes., (Copyright © 2016 by the American Academy of Pediatrics.)
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- 2016
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13. Impact of Sustained Eradication of New Pseudomonas aeruginosa Infection on Long-term Outcomes in Cystic Fibrosis.
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Mayer-Hamblett N, Kloster M, Rosenfeld M, Gibson RL, Retsch-Bogart GZ, Emerson J, Thompson V, and Ramsey BW
- Subjects
- Anti-Bacterial Agents administration & dosage, Child, Child, Preschool, Cohort Studies, Female, Follow-Up Studies, Humans, Infant, Male, Pseudomonas Infections complications, Pseudomonas Infections physiopathology, Treatment Outcome, Anti-Bacterial Agents therapeutic use, Cystic Fibrosis epidemiology, Cystic Fibrosis microbiology, Pseudomonas Infections drug therapy, Pseudomonas Infections epidemiology, Pseudomonas aeruginosa
- Abstract
Background: Pseudomonas aeruginosa (Pa) is the most important pathogen infecting the airways in individuals with cystic fibrosis. A key question is whether children with newly acquired Pa infection who are able to achieve sustained eradication after early antipseudomonal therapy demonstrate improved long-term health outcomes compared with those who are unable to achieve a sustained microbiologic response., Methods: This cohort study utilized observational follow-up data on children participating in the Early Pseudomonas Infection Control trial who received standardized therapy for newly acquired Pa. Sustained eradicators were defined as those who maintained Pa-negative cultures for 12 months after initial antipseudomonal therapy. Associations between eradication status and outcomes were assessed., Results: Of the 249 trial participants included in the study, 172 (69%) achieved sustained eradication of Pa during the trial (sustained eradicators). Over the median 5-year follow-up, sustained eradicators had a 74% reduced risk of developing chronic Pa (hazard ratio [HR], 0.26; 95% confidence interval [CI], .17-.40) and a 57% reduced risk of mucoidy (HR, 0.43; 95% CI, .25-.73) compared with nonsustained eradicators. Sustained eradicators had significantly less anti-Pa antibiotic usage during follow-up compared with nonsustained eradicators. There was no association between eradication status and clinical outcomes including rate of exacerbation and lung function decline., Conclusions: This is the first study to quantify the long-term durability of microbiological response associated with early antipseudomonal therapy, demonstrating the critical importance of optimizing antipseudomonal therapies during early Pa infection. The clinical impact of failure to achieve sustained Pa eradication remains unclear, however, and may be confounded by anti-Pa antibiotic usage., Clinical Trials Registration: NCT00097773., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2015
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14. Pseudomonas aeruginosa in vitro phenotypes distinguish cystic fibrosis infection stages and outcomes.
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Mayer-Hamblett N, Rosenfeld M, Gibson RL, Ramsey BW, Kulasekara HD, Retsch-Bogart GZ, Morgan W, Wolter DJ, Pope CE, Houston LS, Kulasekara BR, Khan U, Burns JL, Miller SI, and Hoffman LR
- Subjects
- Adolescent, Child, Child, Preschool, Cystic Fibrosis microbiology, Disease Progression, Female, Humans, In Vitro Techniques, Infant, Logistic Models, Male, Multicenter Studies as Topic, Outcome Assessment, Health Care, Phenotype, Prospective Studies, Pseudomonas Infections genetics, Pseudomonas aeruginosa isolation & purification, Cystic Fibrosis complications, Pseudomonas Infections microbiology, Pseudomonas aeruginosa genetics
- Abstract
Rationale: Pseudomonas aeruginosa undergoes phenotypic changes during cystic fibrosis (CF) lung infection. Although mucoidy is traditionally associated with transition to chronic infection, we hypothesized that additional in vitro phenotypes correlate with this transition and contribute to disease., Objectives: To characterize the relationships between in vitro P. aeruginosa phenotypes, infection stage, and clinical outcomes., Methods: A total of 649 children with CF and newly identified P. aeruginosa were followed for a median 5.4 years during which a total of 2,594 P. aeruginosa isolates were collected. Twenty-six in vitro bacterial phenotypes were assessed among the isolates, including measures of motility, exoproduct production, colony morphology, growth, and metabolism., Measurements and Main Results: P. aeruginosa phenotypes present at the time of culture were associated with both stage of infection (new onset, intermittent, or chronic) and the primary clinical outcome, occurrence of a pulmonary exacerbation (PE) in the subsequent 2 years. Two in vitro P. aeruginosa phenotypes best distinguished infection stages: pyoverdine production (31% of new-onset cultures, 48% of intermittent, 69% of chronic) and reduced protease production (31%, 39%, and 65%, respectively). The best P. aeruginosa phenotypic predictors of subsequent occurrence of a PE were mucoidy (odds ratio, 1.75; 95% confidence interval, 1.19-2.57) and reduced twitching motility (odds ratio, 1.43; 95% confidence interval, 1.11-1.84)., Conclusions: In this large epidemiologic study of CF P. aeruginosa adaptation, P. aeruginosa isolates exhibited two in vitro phenotypes that best distinguished early and later infection stages. Among the many phenotypes tested, mucoidy and reduced twitching best predicted subsequent PE. These phenotypes indicate potentially useful prognostic markers of transition to chronic infection and advancing lung disease.
- Published
- 2014
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15. Highly effective cystic fibrosis clinical research teams: critical success factors.
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Retsch-Bogart GZ, Van Dalfsen JM, Marshall BC, George C, Pilewski JM, Nelson EC, Goss CH, and Ramsey BW
- Subjects
- Academic Medical Centers, Adult, Benchmarking, Child, Clinical Trials as Topic statistics & numerical data, Humans, Patient Selection, Biomedical Research organization & administration, Cystic Fibrosis, Institutional Management Teams organization & administration
- Abstract
Background: Bringing new therapies to patients with rare diseases depends in part on optimizing clinical trial conduct through efficient study start-up processes and rapid enrollment. Suboptimal execution of clinical trials in academic medical centers not only results in high cost to institutions and sponsors, but also delays the availability of new therapies. Addressing the factors that contribute to poor outcomes requires novel, systematic approaches tailored to the institution and disease under study., Objective: To use clinical trial performance metrics data analysis to select high-performing cystic fibrosis (CF) clinical research teams and then identify factors contributing to their success., Design: Mixed-methods research, including semi-structured qualitative interviews of high-performing research teams., Participants: CF research teams at nine clinical centers from the CF Foundation Therapeutics Development Network., Approach: Survey of site characteristics, direct observation of team meetings and facilities, and semi-structured interviews with clinical research team members and institutional program managers and leaders in clinical research., Key Results: Critical success factors noted at all nine high-performing centers were: 1) strong leadership, 2) established and effective communication within the research team and with the clinical care team, and 3) adequate staff. Other frequent characteristics included a mature culture of research, customer service orientation in interactions with study participants, shared efficient processes, continuous process improvement activities, and a businesslike approach to clinical research., Conclusions: Clinical research metrics allowed identification of high-performing clinical research teams. Site visits identified several critical factors leading to highly successful teams that may help other clinical research teams improve clinical trial performance.
- Published
- 2014
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16. Inhaled aztreonam for chronic Burkholderia infection in cystic fibrosis: a placebo-controlled trial.
- Author
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Tullis DE, Burns JL, Retsch-Bogart GZ, Bresnik M, Henig NR, Lewis SA, and Lipuma JJ
- Subjects
- Administration, Inhalation, Adolescent, Adult, Child, Chronic Disease, Double-Blind Method, Female, Humans, Male, Placebos, Treatment Outcome, Young Adult, Anti-Bacterial Agents administration & dosage, Aztreonam administration & dosage, Burkholderia Infections drug therapy, Cystic Fibrosis microbiology
- Abstract
Background: Individuals with Burkholderia spp. infection have historically been excluded from efficacy trials of inhaled antibiotics, including aztreonam for inhalation solution (AZLI)., Methods: A double-blind, placebo-controlled, 24-week trial of continuous AZLI/placebo treatment was undertaken in individuals with cystic fibrosis (CF) and chronic Burkholderia spp. infection. All subjects also received usual medical care (determined by their physicians). Additional antibiotic use was not restricted., Results: Baseline FEV1% predicted values ranged from 15.8% to 114.6%. No significant treatment differences (AZLI vs. placebo) were observed at week 24 for any endpoints, including FEV1% predicted, number of respiratory exacerbations requiring systemic/inhaled antibiotics, or hospitalizations. Continuous AZLI administration was well tolerated. Burkholderia spp. susceptibility to antibiotics commonly used in CF therapy showed little change., Conclusions: 24-weeks of continuous AZLI treatment did not significantly improve lung function in CF subjects with chronic Burkholderia spp. infection. Non-study antibiotic use may have confounded any potential AZLI effects., (© 2013.)
- Published
- 2014
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17. Comparison of endoscopic versus 3D CT derived airway measurements.
- Author
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Calloway HE, Kimbell JS, Davis SD, Retsch-Bogart GZ, Pitkin EA, Abode K, Superfine R, and Zdanski CJ
- Subjects
- Adult, Airway Management, Airway Resistance, Humans, Manikins, Models, Anatomic, Respiration, Respiratory System pathology, Sensitivity and Specificity, Tomography, X-Ray Computed methods, Tracheal Stenosis pathology, Video Recording, Bronchoscopy methods, Imaging, Three-Dimensional, Respiratory System diagnostic imaging, Tracheal Stenosis diagnostic imaging
- Abstract
Objectives/hypothesis: To understand: 1) how endoscopic airway measurements compare to three-dimensional (3D) CT derived measurements; 2) where each technique is potentially useful; and 3) where each has limitations., Study Design: Compare airway diameters and cross-sectional areas from endoscopic images and CT derived 3D reconstructions., Methods: Videobronchoscopy was performed and recorded on an adult-sized commercially available airway mannequin. At various levels, cross-sectional areas were measured from still video frames using a referent placed via the biopsy port. A 3D reconstruction was generated from a high resolution CT of the mannequin; planar sections were cut at similar cross-sectional levels; and cross-sectional areas were obtained., Results: At three levels of mechanically generated tracheal stricture, the differences between the endoscopic measurement and CT-derived cross-sectional area were 1%, 0%, and 7% (1.8, 0.8, and 14 mm²). At the vocal folds, the difference was 9% (7.8 mm²). The tip of the epiglottis and width of the epiglottis differed by 27% and 10% (18.73 mm², 0.40 mm). The airway measurements at the base of tongue, minimal cross-sectional area of the pharynx, and choana differed by 26%, 36%, and 30% (101.40 mm², 36.67 mm², 122.71 mm²)., Conclusions: Endoscopy is an effective tool for obtaining airway measurements compared with 3D reconstructions derived from CT. Concordance is best in geometrically simple areas where the entire cross-section measured is visible within one field of view (trachea, round; vocal folds, triangular) versus geometrically complex areas that encompass more than one field of view (i.e. pharynx, choana).
- Published
- 2013
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18. An 18-month study of the safety and efficacy of repeated courses of inhaled aztreonam lysine in cystic fibrosis.
- Author
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Oermann CM, Retsch-Bogart GZ, Quittner AL, Gibson RL, McCoy KS, Montgomery AB, and Cooper PJ
- Subjects
- Administration, Inhalation, Adolescent, Adult, Aged, Anti-Bacterial Agents administration & dosage, Anti-Bacterial Agents adverse effects, Aztreonam administration & dosage, Aztreonam adverse effects, Child, Chronic Disease, Dose-Response Relationship, Drug, Female, Humans, Male, Middle Aged, Patient Compliance, Quality of Life, Respiratory Function Tests, Sputum microbiology, Treatment Outcome, Young Adult, Anti-Bacterial Agents therapeutic use, Aztreonam therapeutic use, Cystic Fibrosis microbiology, Pseudomonas Infections drug therapy, Pseudomonas aeruginosa
- Abstract
Chronic airway infection with Pseudomonas aeruginosa (PA) causes morbidity and mortality in patients with cystic fibrosis (CF). Additional anti-PA therapies are needed to improve health status and health-related quality of life. AIR-CF3 was an international 18-month, open-label study to evaluate the safety and efficacy of repeated courses of aztreonam for inhalation solution (AZLI, now marketed as Cayston®) in patients aged ≥ 6 years with CF and PA infection who previously participated in one of two Phase 3 studies: AIR-CF1 or AIR-CF2. Patients received up to nine courses (28 days on/28 days off) of 75 mg AZLI two (BID) or three times daily (TID) based on randomization in the previous trials. 274 patients, mean age 28.5 years (range: 8-74 years), participated. Mean treatment adherence was high (92.0% BID group, 88.0% TID group). Hospitalization rates were low and adverse events were consistent with CF. With each course of AZLI, FEV(1) and scores on the Cystic Fibrosis Questionnaire-Revised Respiratory Symptom scale improved and bacterial density in sputum was reduced. Benefits waned in the 28 days off therapy, but weight gain was sustained over the 18 months. There were no sustained decreases in PA susceptibility. A dose response was observed; AZLI TID-treated patients demonstrated greater improvements in lung function and respiratory symptoms over 18 months. Repeated intermittent 28-day courses of AZLI treatment were well tolerated. Clinical benefits in pulmonary function, health-related quality of life, and weight were observed with each course of therapy. AZLI is a safe and effective new therapy in patients with CF and PA airway infection.
- Published
- 2010
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- View/download PDF
19. Efficacy and safety of inhaled aztreonam lysine for airway pseudomonas in cystic fibrosis.
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Retsch-Bogart GZ, Quittner AL, Gibson RL, Oermann CM, McCoy KS, Montgomery AB, and Cooper PJ
- Subjects
- Administration, Inhalation, Adolescent, Adult, Aged, Child, Cystic Fibrosis physiopathology, Double-Blind Method, Female, Forced Expiratory Volume, Humans, Male, Middle Aged, Pseudomonas Infections etiology, Sputum microbiology, Treatment Outcome, Young Adult, Anti-Bacterial Agents administration & dosage, Aztreonam administration & dosage, Cystic Fibrosis complications, Pseudomonas Infections drug therapy
- Abstract
Background: We assessed the short-term efficacy and safety of aztreonam lysine for inhalation (AZLI [an aerosolized monobactam antibiotic]) in patients with cystic fibrosis (CF) and Pseudomonas aeruginosa (PA) airway infection., Methods: In this randomized, double-blind, placebo-controlled, international study (AIR-CF1 trial; June 2005 to April 2007), patients (n = 164; >or= 6 years of age) with FEV(1) >or= 25% and
- Published
- 2009
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20. A phase 2 study of aztreonam lysine for inhalation to treat patients with cystic fibrosis and Pseudomonas aeruginosa infection.
- Author
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Retsch-Bogart GZ, Burns JL, Otto KL, Liou TG, McCoy K, Oermann C, and Gibson RL
- Subjects
- Administration, Inhalation, Adolescent, Adult, Anti-Bacterial Agents administration & dosage, Aztreonam administration & dosage, Double-Blind Method, Female, Forced Expiratory Flow Rates, Humans, Male, Nebulizers and Vaporizers, Time Factors, Treatment Outcome, Anti-Bacterial Agents therapeutic use, Aztreonam therapeutic use, Cystic Fibrosis complications, Cystic Fibrosis drug therapy, Pseudomonas Infections complications, Pseudomonas Infections drug therapy
- Abstract
Background: Aztreonam lysine for inhalation (AZLI) is being developed for treatment of CF patients with Pseudomonas aeruginosa airway infection., Methods: This double-blind, randomized, placebo-controlled Phase 2 study evaluated the safety, tolerability and efficacy of 75 and 225 mg AZLI administered BID for 14 days using the eFlow Electronic Nebulizer (Pari Innovative Manufacturers, Inc., Midlothian, VA). Patients were 13 years and older with FEV1>or=40% predicted, chronic P. aeruginosa infection, and had used no anti-pseudomonal antibiotics for 56 days., Results: Of 131 patients screened, 105 received AZLI or placebo. Mean age was 26 years and mean FEV1 percent predicted was 77% at baseline. There was a statistically significant reduction, compared to placebo, in P. aeruginosa CFU density in each AZLI group at Days 7 and 14 (P<0.001). The planned primary analysis, percent change in FEV1 at Day 14, demonstrated no statistically significant difference. Post hoc analysis demonstrated significant increase in FEV1 at Day 7 for the subset of patients with baseline FEV1<75% predicted in the 225 mg AZLI group. Bronchodilator use was associated with greater improvement in FEV1, as well as greater reduction in P. aeruginosa bacterial density and higher plasma aztreonam concentrations in the 225 mg AZLI group. Adverse events were similar between placebo and AZLI although there was a trend toward increased respiratory symptoms in the 225 mg AZLI group., Conclusion: These data support the further development of AZLI and provide information for the design of subsequent studies., (Copyright (c) 2007 Wiley-Liss, Inc.)
- Published
- 2008
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21. Microbiology, safety, and pharmacokinetics of aztreonam lysinate for inhalation in patients with cystic fibrosis.
- Author
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Gibson RL, Retsch-Bogart GZ, Oermann C, Milla C, Pilewski J, Daines C, Ahrens R, Leon K, Cohen M, McNamara S, Callahan TL, Markus R, and Burns JL
- Subjects
- Administration, Inhalation, Adolescent, Adult, Anti-Bacterial Agents pharmacology, Aztreonam pharmacology, Double-Blind Method, Female, Humans, Male, Microbial Sensitivity Tests, Middle Aged, Sputum metabolism, Anti-Bacterial Agents pharmacokinetics, Aztreonam pharmacokinetics, Cystic Fibrosis metabolism, Cystic Fibrosis microbiology
- Abstract
Background: Aztreonam lysinate for inhalation (AI) is a novel monobactam formulation being investigated for pulmonary Pseudomonas aeruginosa infections in patients with cystic fibrosis (CF)., Methods: Pre-clinical studies investigated the pre- and post-nebulization activity of AI and its activity in the presence of CF sputum. A double-blind, placebo-controlled, dose-escalation trial determined pharmacokinetics and tolerability of AI in subjects with CF. Single daily escalating doses of AI 75, 150, or 225 mg, or placebo were self-administered using an eFlow Electronic Nebulizer. Sputum samples were collected up to 4 hr and blood samples up to 8 hr post-dose., Results: AI activity against multiple CF isolates was retained after nebulization via eFlow, and activity was not inhibited by CF sputum. All 12 adult subjects and 11/12 adolescents tolerated all AI doses. One patient had an asymptomatic FEV1 decrease > 20% with the 150 mg dose. Median aztreonam sputum concentrations in adults 10 min after AI 75, 150, and 225 mg were 383, 879, and 985 microg/g, respectively. Median sputum concentrations in adolescents 10 min after AI 75, 150, and 225 mg were 324, 387, and 260 microg/g, respectively. Systemic exposure to AI was low. Plasma pharmacokinetics in adults receiving AI 75 mg were Cmax = 419 ng/g, Tmax = 0.99 hr, t1/2 = 2.1 hr. Aztreonam concentrations in sputum were at or above the MIC50 for at least 4 hr post-dose., Conclusion: These data support the continued development of AI for treatment of pulmonary infections in patients with CF.
- Published
- 2006
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22. Renal failure and vestibular toxicity in an adolescent with cystic fibrosis receiving gentamicin and standard-dose ibuprofen.
- Author
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Scott CS, Retsch-Bogart GZ, and Henry MM
- Subjects
- Adolescent, Humans, Male, Water-Electrolyte Balance, Anti-Bacterial Agents adverse effects, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Cystic Fibrosis drug therapy, Gentamicins adverse effects, Ibuprofen adverse effects, Renal Insufficiency chemically induced, Vestibular Diseases chemically induced
- Abstract
Gentamicin and standard-dose ibuprofen were administered to an adolescent with cystic fibrosis who developed renal failure and severe vestibulotoxicity. A contributing factor was possible suboptimal intravascular volume status. Because of the potential severity of this drug interaction, hydration status and renal and vestibular functions should be closely monitored in patients receiving ibuprofen and intravenous aminoglycosides concomitantly., (Copyright 2001 Wiley-Liss, Inc.)
- Published
- 2001
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23. Pharmacokinetics of ibuprofen enantiomers in children with cystic fibrosis.
- Author
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Dong JQ, Ni L, Scott CS, Retsch-Bogart GZ, and Smith PC
- Subjects
- Adolescent, Adult, Area Under Curve, Child, Child, Preschool, Cystic Fibrosis metabolism, Female, Humans, Male, Stereoisomerism, Anti-Inflammatory Agents, Non-Steroidal pharmacokinetics, Cystic Fibrosis drug therapy, Ibuprofen pharmacokinetics
- Abstract
Chiral inversion of R(-)- to S(+)-ibuprofen in children with cystic fibrosis was investigated. Children with cystic fibrosis (n = 38, ages 2-13 years) were administered a single oral dose of racemic ibuprofen (20 mg/kg), and the pharmacokinetics of ibuprofen was found to be stereoselective. Mean Cmax, AUC, apparent CL/F, and Varea/F of S-ibuprofen were significantly different from those of R-ibuprofen. The enantiomeric ratio of plasma AUC (S:R = 2.09:1) and of free and conjugated ibuprofen in urine (S:R = 13.9:1) of children with cystic fibrosis was not different from reported values for healthy children and adults. No significant gender difference was observed for any of the pharmacokinetic parameters determined. However, there was an inverse linear relationship between the CL/F of R-ibuprofen and age in children with cystic fibrosis. Apparent CL/F was higher in children with cystic fibrosis than previously reported for healthy children; therefore, higher doses of ibuprofen would be necessary for children with cystic fibrosis.
- Published
- 2000
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24. The pharmacokinetics of ibuprofen suspension, chewable tablets, and tablets in children with cystic fibrosis.
- Author
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Scott CS, Retsch-Bogart GZ, Kustra RP, Graham KM, Glasscock BJ, and Smith PC
- Subjects
- Administration, Oral, Adolescent, Analysis of Variance, Area Under Curve, Child, Child, Preschool, Chromatography, High Pressure Liquid, Female, Half-Life, Humans, Ibuprofen administration & dosage, Ibuprofen blood, Male, Respiratory Function Tests, Suspensions, Tablets, Cystic Fibrosis metabolism, Ibuprofen pharmacokinetics
- Abstract
Objectives: The objectives of this study were to compare the pharmacokinetic parameters of ibuprofen administered as a suspension, chewable tablet, or tablet in children with cystic fibrosis and to determine the optimal blood sampling times for measuring ibuprofen peak concentrations., Study Design: A single oral 20 mg/kg dose of ibuprofen was administered, and blood samples were obtained at 15, 30, 45, 60, 120, 240, and 360 minutes after the dose was administered. Peak plasma concentration (Cmax ), time to peak concentration (Tmax ), and other pharmacokinetic parameters were determined and compared (analysis of variance and analysis of covariance)., Results: Thirty-eight children were included (22, 4, and 12 in the suspension, chewable tablet, and tablet groups, respectively). Tmax was the only parameter for which statistical differences were noted (suspension vs tablet, P =.02). After age and sex were removed as potential confounding variables, Tmax remained statistically different (P =.001)., Conclusions: A 20 mg/kg dose of ibuprofen suspension is recommended, with blood samples for pharmacokinetic analysis obtained 30, 45, and 60 minutes after the dose is administered. Obtaining the first blood sample 1 hour after dose administration will miss approximately 90% of peak concentrations, increasing the likelihood of overdosing.
- Published
- 1999
- Full Text
- View/download PDF
25. Urticaria associated with the pilocarpine iontophoresis sweat test.
- Author
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LeGrys VA and Retsch-Bogart GZ
- Subjects
- Child, Chlorides analysis, Female, Histamine H1 Antagonists therapeutic use, Humans, Pilocarpine immunology, Urticaria prevention & control, Cystic Fibrosis diagnosis, Iontophoresis, Pilocarpine adverse effects, Sweat chemistry, Urticaria chemically induced
- Published
- 1997
- Full Text
- View/download PDF
26. Cellular localization of messenger RNAs for insulin-like growth factors (IGFs), their receptors and binding proteins during fetal rat lung development.
- Author
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Retsch-Bogart GZ, Moats-Staats BM, Howard K, D'Ercole AJ, and Stiles AD
- Subjects
- Animals, Bronchi chemistry, Bronchi embryology, Epithelium chemistry, Epithelium embryology, Female, In Situ Hybridization, Lung chemistry, Pregnancy, Rats, Rats, Sprague-Dawley, Tissue Distribution, Insulin-Like Growth Factor Binding Proteins genetics, Insulin-Like Growth Factor I genetics, Insulin-Like Growth Factor II genetics, Lung embryology, RNA, Messenger analysis, Receptors, Somatomedin genetics
- Abstract
To gain insight into the role of the insulin-like growth factors (IGFs) in regulating lung development, we have used in situ hybridization histochemistry (ISHH) to examine the ontogeny and sites of expression of IGF-I and IGF-II, IGF binding proteins (IGFBP-1 to IGFBP-6), and IGF cell surface receptors in fetal rat lung from 15 to 21 days of gestation. Both IGF-I and IGF-II mRNAs were expressed throughout the developmental period studied with little change in apparent abundance. IGF-I mRNA localized to mesenchymal cells, especially those surrounding airway epithelium, while IGF-II mRNA, which was somewhat more abundant, localized predominantly to epithelia. The type 1 IGF receptor, the receptor that likely mediates the actions of both IGFs, was expressed widely in virtually all cells, whereas the expression of the type 2 IGF receptor, thought to be involved in IGF internalization and degradation, was confined to the mesenchyme and medial layers of intrapulmonary vessels. As with the IGFs, there was little apparent change in the abundance of IGF receptor mRNAs through fetal development, and the type 2 IGF receptor mRNA was more abundant. The expression of IGFBPs changed significantly during lung development. IGFBP-2, -3, -4, and -5 were expressed from day 15 of gestation, but their sites of expression and ontogeny differed. IGFBP-2 mRNA expression was abundant and constant throughout gestation and was confined to proximal and distal airway epithelia. IGFBP-3 and IGFBP-5 also were expressed by proximal airway epithelia, but also exhibited significant expression in interstitial mesenchyme and in mesenchyme surrounding vessels. The abundance of both increased as gestation progressed (IGFBP-5 greater than IGFBP-3). IGFBP-4 mRNA was confined to interstitial mesenchyme and its abundance peaked at days 16 to 19 of gestation. We found no evidence for expression of either IGFBP-1 or IGFBP-6. We conclude that the expression of IGF-I, IGF-II, and the type 1 IGF receptor throughout gestation in the lung supports a role for the IGFs in lung growth and development. The complex pattern of IGFBP expression (differing sites and ontogeny of expression) suggests that the IGFBPs modulate IGF actions at specific target sites. Furthermore, because there is little change in the expression of IGFs or IGF receptor mRNAs during fetal lung development, regulation of IGFBP expression may be essential to the control of IGF actions during lung development.
- Published
- 1996
- Full Text
- View/download PDF
27. Insulin-like growth factor-I (IGF-I) antisense oligodeoxynucleotide mediated inhibition of DNA synthesis by WI-38 cells: evidence for autocrine actions of IGF-I.
- Author
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Moats-Staats BM, Retsch-Bogart GZ, Price WA, Jarvis HW, D'Ercole AJ, and Stiles AD
- Subjects
- Base Sequence, Carrier Proteins biosynthesis, Cell Line, Depression, Chemical, Fibroblasts metabolism, Humans, Insulin-Like Growth Factor Binding Proteins, Insulin-Like Growth Factor I biosynthesis, Insulin-Like Growth Factor I genetics, Molecular Sequence Data, Receptor, IGF Type 1 biosynthesis, DNA Replication drug effects, DNA, Antisense pharmacology, Fibroblasts drug effects, Insulin-Like Growth Factor I physiology
- Abstract
Insulin-like growth factor-I (IGF-I) is elaborated into culture medium by WI-38 cells, a human embryonic lung fibroblast cell line, and may participate in the autocrine stimulation of DNA synthesis. We have confirmed the expression of IGF-I by these cells and documented that they express the type 1 IGF receptor and a number of IGF-binding proteins. In situ hybridization histochemistry demonstrated relatively uniform expression of IGF-I and type 1 IGF receptor transcripts among WI-38 cells. To determine whether WI-38-synthesized IGF-I exerted mitogenic effects, a 15-base oligodeoxynucleotide complementary to the 5'IGF-I mRNA sequence (IGF-I AS-Oligo), including the translation start site, was incubated with cultured cells in an attempt to inhibit IGF-I synthesis. The IGF-I AS-Oligo was stable in cell culture, formed intracellular duplexes with IGF-I mRNA, and at 2 microM reduced IGF-I in conditioned medium by 83%. The IGF-I AS-Oligo also inhibited [3H]thymidine incorporation into DNA in a dose-dependent fashion (by 77% at 2 microM and by 95% at 20 microM). This reduction in DNA synthesis was prevented when the medium was supplemented with 100 ng/ml IGF-I. The oligomer also decreased the abundance of IGF-binding proteins in conditioned medium. The IGF-I AS-Oligo appears to exert its effects by blocking IGF-I mRNA translation, rather than blocking transcription or initiating RNase-H activity, because the abundance of IGF-I transcripts was not decreased in its presence. These findings confirm an essential role for IGF-I in WI-38 cell DNA synthesis and are consistent with autocrine actions by WI-38 cell IGF-I.
- Published
- 1993
- Full Text
- View/download PDF
28. Canine tracheal epithelial cells express the type 1 insulin-like growth factor receptor and proliferate in response to insulin-like growth factor I.
- Author
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Retsch-Bogart GZ, Stiles AD, Moats-Staats BM, Van Scott MR, Boucher RC, and D'Ercole AJ
- Subjects
- Animals, Cell Division, Cells, Cultured, DNA metabolism, DNA Replication, Dogs, Epithelium metabolism, Epithelium ultrastructure, Mitogens genetics, Receptors, Cell Surface genetics, Receptors, Somatomedin, Trachea cytology, Trachea growth & development, Insulin-Like Growth Factor I pharmacology, Mitogens biosynthesis, Receptors, Cell Surface biosynthesis, Somatomedins pharmacology, Trachea metabolism
- Abstract
Disaggregated airway epithelial cells replicate in serum-free media containing supraphysiologic concentrations of insulin. To examine the hypothesis that the type 1 insulin-like growth factor (IGF) receptor mediates the mitogenic action of insulin on these cells, we studied the mitogenic effects of IGF-I and insulin, and the expression of type 1 IGF receptors in primary cultures of adult canine tracheal epithelial cells. Isolated tracheal epithelial cells were grown in varying concentrations of IGF-I or insulin in Ham's F12 medium supplemented with transferrin, cholera toxin, and endothelial cell growth supplement. Both IGF-I and insulin increased DNA synthesis (measured as [3H]thymidine incorporation into DNA) and cell number in a concentration-dependent fashion, but IGF-I was at least 20 to 60 times more potent than insulin in its mitogenic effects. No additive or synergistic effect was observed with the simultaneous addition of IGF-I and insulin in maximally effective doses. A monoclonal antibody directed against the type 1 IGF receptor (alpha IR3) blocked the mitogenic activity of both IGF-I and insulin. Affinity labeling of type 1 IGF receptors by covalent cross-linking with disuccinimidyl suberate demonstrated the tracheal epithelial cell IGF-I binding moiety to have a relative molecular weight of 130,000 D. Binding of [125I]IGF-I to this protein was inhibited by low concentrations of IGF-I, relative to insulin, and by alpha IR3. An 11-kb transcript characteristic of mRNA for the type 1 IGF receptor was recognized in poly(A+) RNA derived from cultured canine tracheal epithelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1990
- Full Text
- View/download PDF
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