24 results on '"Tullis, D. Elizabeth"'
Search Results
2. Continuous alternating inhaled antibiotics for chronic pseudomonal infection in cystic fibrosis
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Flume, Patrick A., Clancy, John P., Retsch-Bogart, George Z., Tullis, D. Elizabeth, Bresnik, Mark, Derchak, P. Alex, Lewis, Sandra A., and Ramsey, Bonnie W.
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- 2016
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3. Microbiome networks and change-point analysis reveal key community changes associated with cystic fibrosis pulmonary exacerbations
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Layeghifard, Mehdi, Li, Hannah, Wang, Pauline W., Donaldson, Sylva L., Coburn, Bryan, Clark, Shawn T., Caballero, Julio Diaz, Zhang, Yu, Tullis, D. Elizabeth, Yau, Yvonne C. W., Waters, Valerie, Hwang, David M., and Guttman, David S.
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- 2019
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4. Inhaled aztreonam for chronic Burkholderia infection in cystic fibrosis: A placebo-controlled trial
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Tullis, D. Elizabeth, Burns, Jane L., Retsch-Bogart, George Z., Bresnik, Mark, Henig, Noreen R., Lewis, Sandra A., and LiPuma, John J.
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- 2014
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5. Feasibility of Internet-Based Health-Related Quality of Life Data Collection in a Large Patient Cohort
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Bhinder, Sacha, Chowdhury, Noori, Granton, John, Krahn, Murray, Tullis, D Elizabeth, Waddell, Thomas K, and Singer, Lianne G
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundPatient registries are commonly used to track survival and medical outcomes in large cohorts. However, large-scale collection of health-related quality of life (HRQOL) data is more challenging because such data must be collected directly from patients. Internet-based HRQOL questionnaires are a potential solution, allowing home data collection with immediate storage in a central database. ObjectivesOur objectives were to investigate the sociodemographic predictors of Internet use and willingness to convey HRQOL information over the Internet in a Canadian tertiary care patient population and to determine whether Internet use patterns of tertiary care patients differ from those of the general Canadian population. Additionally, we sought to identify the success of home completion of Internet-based HRQOL questionnaires, as well as factors hindering home completion. MethodsWe surveyed 644 patients at the Toronto General and St. Michael’s Hospitals from November 2003 through July 2006 within a prospective, longitudinal cohort study of HRQOL in patients with lung disease or lung transplants. Using multiple logistic regression, we assessed patient age, gender, rurality, marital status, and employment or education status as potential sociodemographic predictors of having an Internet-accessible home computer, using email at least weekly, and willingness to complete a quality of life questionnaire over the Internet. Patients electing to complete questionnaires over the Internet were followed from September 2005 through March 2008 to assess completion of HRQOL questionnaires from home, identify barriers for noncompletion, and determine sociodemographic predictors for home completion. ResultsOf the 644 patients, the median age was 51 years, with a similar number of males and females. Most were urban Ontario residents, were unemployed, and were married or in a common-law relationship. Having an Internet-accessible home computer was reported by 79.7% (513/644) of patients and use of email at least weekly by 66.5% (414/623) of patients. A majority of patients (57.1% 368/644) were willing to complete HRQOL questionnaires over the Internet via an emailed link. Of the participating 644 patients, 368 elected to complete future questionnaires from home and, as part of a gradual roll-out of the home HRQOL questionnaire, 211 were sent emails inviting them to do so. Of the invited patients, 78% (165/211) completed at least one questionnaire from home. The most common reason for noncompletion was a lack of or an inability to find time to complete the questionnaire. No statistically significant sociodemographic predictors of Internet use were associated with completion or noncompletion of questionnaires from home. ConclusionsHome, Internet-based HRQOL assessment is feasible in tertiary care patient populations with a high predicted rate of Internet usage based on sociodemographic parameters. A large minority of patients were unwilling or unable to take part in home HRQOL assessments indicating that alternative methods of data collection are still required. However, the majority of patients electing to complete home HRQOL assessments went on to do so over the Internet.
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- 2010
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6. Quality of Life in Cystic Fibrosis
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Tullis, D. Elizabeth and Guyatt, Gordon H.
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- 1995
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7. Incidence and prevalence of diabetes mellitus in patients with cystic fibrosis undergoing lung transplantation before and after lung transplantation
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Hadjiliadis, Denis, Madill, Janet, Chaparro, Cecilia, Tsang, Anna, Waddell, Thomas K, Singer, Lianne G, Hutcheon, Michael A, Keshavjee, Shaf, and Tullis, D Elizabeth
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- 2005
8. Clinical Manifestations of Cystic Fibrosis Among Patients With Diagnosis in Adulthood
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Gilljam, Marita, Ellis, Lynda, Corey, Mary, Zielenski, Julian, Durie, Peter, and Tullis, D. Elizabeth
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- 2004
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9. The Repeatability of Forced Expiratory Volume Measurements in Adults With Cystic Fibrosis
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Stanbrook, Matthew B., Corey, Mary, and Tullis, D. Elizabeth
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- 2004
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10. Pregnancy in Cystic Fibrosis*: Fetal and Maternal Outcome
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Gilljam, Marita, Antoniou, Maria, Shin, Janey, Dupuis, Annie, Corey, Mary, and Tullis, D. Elizabeth
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- 2000
11. Pulmonary Hypertension and Cardiac Function in Adult Cystic Fibrosis*: Role of Hypoxemia
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Fraser, Kristin L., Tullis, D. Elizabeth, Sasson, Zion, Hyland, Robert H., Thornley, Kristine S., and Hanly, Patrick J.
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- 1999
12. Triaging Access to Critical Care Resources in Patients With Chronic Respiratory Diseases in the Event of a Major COVID-19 Surge: Key Highlights From the Canadian Thoracic Society (CTS) Position Statement.
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Gupta, Samir, Batt, Jane, Bourbeau, Jean, Chapman, Kenneth R., Gershon, Andrea, Granton, John, Hambly, Nathan, Hernandez, Paul, Kolb, Martin, Mehta, Sanjay, Mielniczuk, Lisa, Provencher, Steeve, Stephenson, Anne L., Swiston, John, Tullis, D. Elizabeth, Vozoris, Nicholas T., Wald, Joshua, Weatherald, Jason, and Bhutani, Mohit
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COVID-19 ,CHRONICALLY ill ,PATIENT care ,PRESBYCUSIS ,CRITICAL care medicine - Abstract
Cystic Fibrosis Which cystic fibrosis patients have >80% predicted mortality during or in the 6 to 12 months after critical illness (level 1)? Level 3 criteria were validated in the GAP model, predicting a relatively low probability of 1-year mortality.[7] COPD Which COPD patients have >80% predicted mortality during or in the 6 to 12 months after critical illness (level 1)? Which COPD patients have >30% predicted mortality during or in the 6 to 12 months after critical illness (level 3)? Posted on March 28, 2020 https://www.corhealthontario.ca/Clinical-Triage-Protocol-for-Major-Surge-in-COVID-Pandemic-March-28-2020.pdf 5 S. Gupta, J. Batt, J. Bourbeau, Position statement from the Canadian Thoracic Society (CTS) on clinical triage thresholds in respiratory disease patients in the event of a major surge during the Covid-19 pandemic. [Extracted from the article]
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- 2020
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13. A genome-wide association analysis reveals a potential role for recombination in the evolution of antimicrobial resistance in Burkholderia multivorans.
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Diaz Caballero, Julio, Guttman, David S., Clark, Shawn T., Hwang, David M., Yau, Yvonne C. W., Wang, Pauline W., Donaldson, Sylva L., Coburn, Bryan, Tullis, D. Elizabeth, and Waters, Valerie J.
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ANTI-infective agents ,DRUG resistance in bacteria ,BURKHOLDERIA infections ,CYSTIC fibrosis ,GENOMICS ,MORTALITY - Abstract
Cystic fibrosis (CF) lung infections caused by members of the Burkholderia cepacia complex, such as Burkholderia multivorans, are associated with high rates of mortality and morbidity. We performed a population genomics study of 111 B. multivorans sputum isolates from one CF patient through three stages of infection including an early incident isolate, deep sampling of a one-year period of chronic infection occurring weeks before a lung transplant, and deep sampling of a post-transplant infection. We reconstructed the evolutionary history of the population and used a lineage-controlled genome-wide association study (GWAS) approach to identify genetic variants associated with antibiotic resistance. We found the incident isolate was basally related to the rest of the strains and more susceptible to antibiotics from three classes (β-lactams, aminoglycosides, quinolones). The chronic infection isolates diversified into multiple, distinct genetic lineages and showed reduced antimicrobial susceptibility to the same antibiotics. The post-transplant reinfection isolates derived from the same source as the incident isolate and were genetically distinct from the chronic isolates. They also had a level of susceptibility in between that of the incident and chronic isolates. We identified numerous examples of potential parallel pathoadaptation, in which multiple mutations were found in the same locus or even codon. The set of parallel pathoadaptive loci was enriched for functions associated with virulence and resistance. Our GWAS analysis identified statistical associations between a polymorphism in the ampD locus with resistance to β-lactams, and polymorphisms in an araC transcriptional regulator and an outer membrane porin with resistance to both aminoglycosides and quinolones. Additionally, these three loci were independently mutated four, three and two times, respectively, providing further support for parallel pathoadaptation. Finally, we identified a minimum of 14 recombination events, and observed that loci carrying putative parallel pathoadaptations and polymorphisms statistically associated with β-lactam resistance were over-represented in these recombinogenic regions. [ABSTRACT FROM AUTHOR]
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- 2018
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14. Clinical Outcomes Associated with Achromobacter Species Infection in Patients with Cystic Fibrosis.
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Somayaji, Ranjani, Stanojevic, Sanja, Tullis, D. Elizabeth, Stephenson, Anne L., Ratjen, Felix, and Waters, Valerie
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CYSTIC fibrosis treatment ,COMPARATIVE studies ,CYSTIC fibrosis ,GRAM-negative bacterial diseases ,LUNGS ,LUNG transplantation ,RESEARCH methodology ,MEDICAL cooperation ,RESEARCH ,EVALUATION research ,PROPORTIONAL hazards models ,RETROSPECTIVE studies ,DISEASE progression ,GRAM-negative aerobic bacteria ,DISEASE complications - Abstract
Rationale: Achromobacter species are increasingly identified in individuals with cystic fibrosis (CF), but the clinical outcomes in these patients remain poorly understood.Objectives: We aimed to determine the association of Achromobacter infection on clinical outcomes in pediatric and adult patients with CF.Methods: A cohort study of pediatric and adult patients with CF was conducted from 1997 to 2014 in Toronto, Ontario, Canada. Achromobacter spp. infection was categorized as no history of infection, intermittent infection, and chronic infection (two or more positive cultures in the preceding 12 months). Cox models were used to estimate risk of death or transplantation. Mixed-effects models were used to assess odds of pulmonary exacerbations and effect on lung function (FEV1%) by Achromobacter spp.Results: A total of 1,103 patients were followed-up over the course of 18 years; 88 patients (7.3%) had one or more culture for Achromobacter species. Chronic Achromobacter infection was associated with a greater risk of death or transplantation compared with in patients with no history of infection (adjusted hazard ratio, 2.03; 95% confidence interval, 1.05-3.95; P = 0.036). Pulmonary exacerbations were more common in patients with chronic infection, but after adjusting for confounding factors, the effect was no longer significant. The chronic group had lower FEV1%, but it did not worsen after developing chronic infection.Conclusions: Patients with CF and chronic Achromobacter infection are at increased risk of death or transplantation. [ABSTRACT FROM AUTHOR]- Published
- 2017
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15. Navigating social and ethical challenges of biobanking for human microbiome research.
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Chuong, Kim H., Hwang, David M., Tullis, D. Elizabeth, Waters, Valerie J., Yau, Yvonne C. W., Guttman, David S., and O'Doherty, Kieran C.
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BIOBANKS ,HUMAN microbiota ,SCIENCE & ethics ,CYSTIC fibrosis ,DISEASE progression ,LUNG microbiology ,COMMUNICATION ,DIAGNOSIS ,MEDICAL ethics ,MEDICAL research ,PRIVACY ,PUBLIC health ,PUBLIC opinion ,RESEARCH funding ,RESEARCH ethics ,TISSUE banks ,DISCLOSURE - Abstract
Background: Biobanks are considered to be key infrastructures for research development and have generated a lot of debate about their ethical, legal and social implications (ELSI). While the focus has been on human genomic research, rapid advances in human microbiome research further complicate the debate.Discussion: We draw on two cystic fibrosis biobanks in Toronto, Canada, to illustrate our points. The biobanks have been established to facilitate sample and data sharing for research into the link between disease progression and microbial dynamics in the lungs of pediatric and adult patients. We begin by providing an overview of some of the ELSI associated with human microbiome research, particularly on the implications for the broader society. We then discuss ethical considerations regarding the identifiability of samples biobanked for human microbiome research, and examine the issue of return of results and incidental findings. We argue that, for the purposes of research ethics oversight, human microbiome research samples should be treated with the same privacy considerations as human tissues samples. We also suggest that returning individual microbiome-related findings could provide a powerful clinical tool for care management, but highlight the need for a more grounded understanding of contextual factors that may be unique to human microbiome research.Conclusions: We revisit the ELSI of biobanking and consider the impact that human microbiome research might have. Our discussion focuses on identifiability of human microbiome research samples, and return of research results and incidental findings for clinical management. [ABSTRACT FROM AUTHOR]- Published
- 2017
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16. Global Analysis of the Fungal Microbiome in Cystic Fibrosis Patients Reveals Loss of Function of the Transcriptional Repressor Nrg1 as a Mechanism of Pathogen Adaptation.
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Kim, Sang Hu, Clark, Shawn T., Surendra, Anuradha, Copeland, Julia K., Wang, Pauline W., Ammar, Ron, Collins, Cathy, Tullis, D. Elizabeth, Nislow, Corey, Hwang, David M., Guttman, David S., and Cowen, Leah E.
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COLLAGEN diseases ,TRANSCRIPTIONAL repressor CTCF ,FIBROSIS ,HUMAN microbiota ,FILAMENTATION instability ,DISEASE risk factors - Abstract
The microbiome shapes diverse facets of human biology and disease, with the importance of fungi only beginning to be appreciated. Microbial communities infiltrate diverse anatomical sites as with the respiratory tract of healthy humans and those with diseases such as cystic fibrosis, where chronic colonization and infection lead to clinical decline. Although fungi are frequently recovered from cystic fibrosis patient sputum samples and have been associated with deterioration of lung function, understanding of species and population dynamics remains in its infancy. Here, we coupled high-throughput sequencing of the ribosomal RNA internal transcribed spacer 1 (ITS1) with phenotypic and genotypic analyses of fungi from 89 sputum samples from 28 cystic fibrosis patients. Fungal communities defined by sequencing were concordant with those defined by culture-based analyses of 1,603 isolates from the same samples. Different patients harbored distinct fungal communities. There were detectable trends, however, including colonization with Candida and Aspergillus species, which was not perturbed by clinical exacerbation or treatment. We identified considerable inter- and intra-species phenotypic variation in traits important for host adaptation, including antifungal drug resistance and morphogenesis. While variation in drug resistance was largely between species, striking variation in morphogenesis emerged within Candida species. Filamentation was uncoupled from inducing cues in 28 Candida isolates recovered from six patients. The filamentous isolates were resistant to the filamentation-repressive effects of Pseudomonas aeruginosa, implicating inter-kingdom interactions as the selective force. Genome sequencing revealed that all but one of the filamentous isolates harbored mutations in the transcriptional repressor NRG1; such mutations were necessary and sufficient for the filamentous phenotype. Six independent nrg1 mutations arose in Candida isolates from different patients, providing a poignant example of parallel evolution. Together, this combined clinical-genomic approach provides a high-resolution portrait of the fungal microbiome of cystic fibrosis patient lungs and identifies a genetic basis of pathogen adaptation. [ABSTRACT FROM AUTHOR]
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- 2015
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17. Effects of Recipient Age and Diagnosis on Health-related Quality-of-Life Benefit of Lung Transplantation.
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Singer, Lianne G., Chowdhury, Noori A., Faughnan, Marie E., Granton, John, Keshavjee, Shaf, Marras, Theodore K., Tullis, D. Elizabeth, Waddell, Thomas K., and Tomlinson, George
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AGE distribution ,CYSTIC fibrosis ,HEALTH status indicators ,HEALTH surveys ,INTERSTITIAL lung diseases ,LONGITUDINAL method ,OBSTRUCTIVE lung diseases ,LUNG transplantation ,PULMONARY hypertension ,QUALITY of life ,RESEARCH funding ,TRANSPLANTATION of organs, tissues, etc. ,TREATMENT effectiveness ,QUALITY-adjusted life years - Abstract
Rationale: The average age of lung transplant recipients is increasing, and the mix of recipient indications for transplantation is changing.Objectives: To determine whether the health-related quality-of-life (HRQL) benefit of lung transplantation differs by recipient age and diagnosis.Methods: In this prospective cohort study, we obtained serial HRQL measurements in adults with advanced lung disease who subsequently underwent lung transplantation (2004-2012). HRQL assessments included the St. George's Respiratory Questionnaire, 36-Item Short-Form Health Survey (SF-36), EQ-5D, Standard Gamble, and Visual Analog Scale for current health. We used linear mixed effects models for associations between age or diagnosis and changes in HRQL with transplantation. To address potential survivorship bias, we fitted Markov models to the distribution of discrete post-transplant health states (HRQL better than pretransplant, not better, or dead) and estimated quality-adjusted life-years post-transplant.Measurements and Main Results: A total of 430 subjects were listed, 387 were transplanted, and 326 provided both pretransplant and post-transplant data. Transplantation conferred large improvements in all HRQL measures: St. George's change of -47 units (95% confidence interval, -48 to -44), 36-Item Short-Form Health Survey physical component summary score of 17.7 (16.5-18.9), EQ-5D of 0.27 (0.24-0.30), Standard Gamble of 0.48 (0.44-0.51), and Visual Analog of 44 (42-47). Age was not associated with meaningful differences in the HRQL benefits of transplantation. There was less HRQL benefit in interstitial lung disease than in cystic fibrosis.Conclusions: Lung transplantation confers large HRQL benefits, which vary by recipient diagnosis, but do not differ substantially in older recipients. [ABSTRACT FROM AUTHOR]- Published
- 2015
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18. Analysis of the Cystic Fibrosis Lung Microbiota via Serial Illumina Sequencing of Bacterial 16S rRNA Hypervariable.
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Maughan, Heather, Wang, Pauline W., Caballero, Julio Diaz, Fung, Pauline, Yunchen Gong, Donaldson, Sylva L., Lijie Yuan, Keshavjee, Shaf, Yu Zhang, Yau, Yvonne C. W., Waters, Valerie J., Tullis, D. Elizabeth, Hwang, David M., and Guttman, David S.
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BACTERIA ,NUCLEOTIDE sequence ,MICROORGANISMS ,RIBOSOMAL RNA ,GENOMES ,CYSTIC fibrosis ,PATIENTS - Abstract
The characterization of bacterial communities using DNA sequencing has revolutionized our ability to study microbes in nature and discover the ways in which microbial communities affect ecosystem functioning and human health. Here we describe Serial Illumina Sequencing (SI-Seq): a method for deep sequencing of the bacterial 16S rRNA gene using next- generation sequencing technology. SI-Seq serially sequences portions of the V5, V6 and V7 hypervariable regions from barcoded 16S rRNA amplicons using an Illumina short-read genome analyzer. SI-Seq obtains taxonomic resolution similar to 454 pyrosequencing for a fraction of the cost, and can produce hundreds of thousands of reads per sample even with very high multiplexing. We validated SI-Seq using single species and mock community controls, and via a comparison to cystic fibrosis lung microbiota sequenced using 454 FLX Titanium. Our control runs show that SI-Seq has a dynamic range of at least five orders of magnitude, can classify >96% of sequences to the genus level, and performs just as well as 454 and paired-end Illumina methods in estimation of standard microbial ecology diversity measurements. We illustrate the utility of SI-Seq in a pilot sample of central airway secretion samples from cystic fibrosis patients. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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19. Pulmonary Bacterial Communities in Surgically Resected Noncystic Fibrosis Bronchiectasis Lungs Are Similar to Those in Cystic Fibrosis.
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Maughan, Heather, Cunningham, Kristopher S., Wang, Pauline W., Yu Zhang, Cypel, Marcelo, Chaparro, Cecilia, Tullis, D. Elizabeth, Waddell, Thomas K., Keshavjee, Shaf, Liu, Mingyao, Guttman, David S., and Hwang, David M.
- Abstract
Background. Recurrent bacterial infections play a key role in the pathogenesis of bronchiectasis, but conventional microbiologic methods may fail to identify pathogens in many cases. We characterized and compared the pulmonary bacterial communities of cystic fibrosis (CF) and non-CF bronchiectasis patients using a culture-independent molecular approach. Methods. Bacterial 16S rRNA gene libraries were constructed from lung tissue of 10 non-CF bronchiectasis and 21 CF patients, followed by DNA sequencing of isolates from each library. Community characteristics were analyzed and compared between the two groups. Results. A wide range of bacterial diversity was detected in both groups, with between 1 and 21 bacterial taxa found in each patient. Pseudomonas was the most common genus in both groups, comprising 49% of sequences detected and dominating numerically in 13 patients. Although Pseudomonas appeared to be dominant more often in CF patients than in non-CF patients, analysis of entire bacterial communities did not identify significant differences between these two groups. Conclusions. Our data indicate significant diversity in the pulmonary bacterial community of both CF and non-CF bronchiectasis patients and suggest that this community is similar in surgically resected lungs of CF and non-CF bronchiectasis patients. [ABSTRACT FROM AUTHOR]
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- 2012
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20. Amiloride-insensitive nasal potential difference varies with the menstrual cycle in cystic fibrosis.
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Sweezey, Neil B., Smith, David, Corey, Mary, Ellis, Lynda, Carpenter, Susan, Tullis, D. Elizabeth, Durie, Peter, and O'Brodovich, Hugh M.
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- 2007
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21. Infectious Complications following Isolated Lung Transplantation
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Maurer, Janet R., Tullis, D. Elizabeth, Grossman, Ronald F., Vellend, Hillar, Winton, Timothy L., and Patterson, G. Alexander
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- 1992
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22. Conducting Effective Physician Performance Feedback: A Primer for Healthcare Leaders.
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Cheng AH, Manayathu J, Sinclair D, Tullis DE, and Bandiera G
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- Canada, Humans, Leadership, Medical Audit, Patient Satisfaction, Patient Simulation, Physician-Patient Relations, Quality Indicators, Health Care, Clinical Competence, Feedback, Psychological, Physicians, Quality Improvement organization & administration
- Abstract
Physician performance feedback (PPF) can help physicians gain insight into their practice, to identify areas for improvement, and to implement changes to improve care. There is increasing interest in the use of PPF in Canada. However, little is known about the different types of PPF methods and whether PPF can lead to improved physician performance and patient outcomes. We provide a primer for healthcare leaders interested in doing PPF by reviewing common PPF methods. We then describe our institution's experience with physician multi-source feedback and provide strategies to conduct meaningful PPF.
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- 2016
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23. Selective Sweeps and Parallel Pathoadaptation Drive Pseudomonas aeruginosa Evolution in the Cystic Fibrosis Lung.
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Diaz Caballero J, Clark ST, Coburn B, Zhang Y, Wang PW, Donaldson SL, Tullis DE, Yau YC, Waters VJ, Hwang DM, and Guttman DS
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- Adaptation, Biological, Biota, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, Genetics, Population, Genome, Bacterial, Genotype, Humans, Pseudomonas aeruginosa genetics, Pseudomonas aeruginosa isolation & purification, Selection, Genetic, Sequence Analysis, DNA, Sequence Homology, Sputum microbiology, Cystic Fibrosis complications, Evolution, Molecular, Genetic Variation, Lung microbiology, Pseudomonas Infections microbiology, Pseudomonas aeruginosa classification, Pseudomonas aeruginosa physiology
- Abstract
Unlabelled: Pulmonary infections caused by Pseudomonas aeruginosa are a recalcitrant problem in cystic fibrosis (CF) patients. While the clinical implications and long-term evolutionary patterns of these infections are well studied, we know little about the short-term population dynamics that enable this pathogen to persist despite aggressive antimicrobial therapy. Here, we describe a short-term population genomic analysis of 233 P. aeruginosa isolates collected from 12 sputum specimens obtained over a 1-year period from a single patient. Whole-genome sequencing and antimicrobial susceptibility profiling identified the expansion of two clonal lineages. The first lineage originated from the coalescence of the entire sample less than 3 years before the end of the study and gave rise to a high-diversity ancestral population. The second expansion occurred 2 years later and gave rise to a derived population with a strong signal of positive selection. These events show characteristics consistent with recurrent selective sweeps. While we cannot identify the specific mutations responsible for the origins of the clonal lineages, we find that the majority of mutations occur in loci previously associated with virulence and resistance. Additionally, approximately one-third of all mutations occur in loci that are mutated multiple times, highlighting the importance of parallel pathoadaptation. One such locus is the gene encoding penicillin-binding protein 3, which received three independent mutations. Our functional analysis of these alleles shows that they provide differential fitness benefits dependent on the antibiotic under selection. These data reveal that bacterial populations can undergo extensive and dramatic changes that are not revealed by lower-resolution analyses., Importance: Pseudomonas aeruginosa is a bacterial opportunistic pathogen responsible for significant morbidity and mortality in cystic fibrosis (CF) patients. Once it has colonized the lung in CF, it is highly resilient and rarely eradicated. This study presents a deep sampling examination of the fine-scale evolutionary dynamics of P. aeruginosa in the lungs of a chronically infected CF patient. We show that diversity of P. aeruginosa is driven by recurrent clonal emergence and expansion within this patient and identify potential adaptive variants associated with these events. This high-resolution sequencing strategy thus reveals important intraspecies dynamics that explain a clinically important phenomenon not evident at a lower-resolution analysis of community structure., (Copyright © 2015 Diaz Caballero et al.)
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- 2015
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24. Airway inflammation and infection in congenital bilateral absence of the vas deferens.
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Gilljam M, Moltyaner Y, Downey GP, Devlin R, Durie P, Cantin AM, Zielenski J, and Tullis DE
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- Adult, Bronchi pathology, Bronchoalveolar Lavage Fluid chemistry, Bronchoalveolar Lavage Fluid cytology, Bronchoalveolar Lavage Fluid microbiology, Cell Count, Cystic Fibrosis diagnosis, Cystic Fibrosis Transmembrane Conductance Regulator genetics, Cytokines analysis, Humans, In Vitro Techniques, Inflammation, Inflammation Mediators analysis, Leukocyte Elastase metabolism, Male, Middle Aged, Mutation, Neutrophils metabolism, Respiratory Tract Infections diagnosis, Cystic Fibrosis complications, Respiratory Tract Infections complications, Vas Deferens abnormalities
- Abstract
In cystic fibrosis (CF), airway disease begins early in life. Bacteria and elevated levels of neutrophils and inflammatory mediators have been detected in bronchoalveolar lavage (BAL) fluid from infants with CF. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) are common in men with congenital bilateral absence of the vas deferens (CBAVD) and it has been suggested that this syndrome represents a mild form of CF. We hypothesized that men with CBAVD also have subclinical pulmonary disease. Bronchoscopy with BAL, viral and quantitative bacterial cultures, and analyses of total and differential cell count, cytokines, and free neutrophil elastase was performed in eight men with CBAVD, who had mutations in the CFTR and intermediate or elevated sweat chloride levels, and in four healthy control subjects. There was light growth of Staphylococcus aureus in one of eight men with CBAVD, and small numbers of opportunistic gram-negative bacteria in six of eight men with CBAVD and in one control subject. BAL cell counts and neutrophil elastase were within the normal range. Interleukin-8 and tumor necrosis factor-alpha levels were higher for men with CBAVD than for control subjects. These data suggest that mutations in the CFTR in men with CBAVD, in addition to causing infertility, lead to subclinical bacterial pulmonary infection and inflammation consistent with mild CF.
- Published
- 2004
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