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Background Pseudomonas aeruginosa is a multidrug-resistant pathogen causing recalcitrant pulmonary infections in people with cystic fibrosis (pwCF). Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have been developed that partially correct the defective chloride channel driving disease. Despite the many clinical benefits, studies in adults have demonstrated that while P. aeruginosa sputum load decreases, chronic infection persists. Here, we investigate how P. aeruginosa in pwCF may change in the altered lung environment after CFTR modulation. Methods P. aeruginosa strains (n = 105) were isolated from the sputum of 11 chronically colonized pwCF at baseline and up to 21 months posttreatment with elexacaftor-tezacaftor-ivacaftor or tezacaftor-ivacaftor. Phenotypic characterization and comparative genomics were performed. Results Clonal lineages of P. aeruginosa persisted after therapy, with no evidence of displacement by alternative strains. We identified commonly mutated genes among patient isolates that may be positively selected for in the CFTR-modulated lung. However, classic chronic P. aeruginosa phenotypes such as mucoid morphology were sustained, and isolates remained just as resistant to clinically relevant antibiotics. Conclusions Despite the clinical benefits of CFTR modulators, clonal lineages of P. aeruginosa persist that may prove just as difficult to manage in the future, especially in pwCF with advanced lung disease. [ABSTRACT FROM AUTHOR]

Introduction: The Burkholderia cepacia complex encompasses a group of gram-negative opportunistic pathogens that cause chronic lung infections in people with cystic fibrosis. Distinct from other respiratory pathogens, Burkholderia causes a unique clinical disease in a subset of patients known as 'cepacia syndrome', fulminant pneumonia accompanied by bacteraemia and sepsis with a mortality rate of up to 75%. Due to the bacteraemia associated with this disease, the mechanisms that allow Burkholderia to resist the bactericidal effects of serum complement-depending killing are vital. Antibodies usually promote serum killing; however, we have described 'cloaking antibodies', specific for lipopolysaccharides that paradoxically protect serum-sensitive bacteria from complement-mediated lysis. Cloaking antibodies that protect Pseudomonas aeruginosa have been found in 24%-41% of patients with chronic lung diseases. The presence of these antibodies is also associated with worse clinical outcomes. Here, we sought to determine the relevance of cloaking antibodies in patients with Burkholderia infection. Methods: Twelve Burkholderia spp. were isolated from nine pwCF and characterised for susceptibility to healthy control serum. Patient serum was analysed for the titre of the cloaking antibody. The ability of the patient serum to prevent healthy control serum (HCS) killing of its cognate isolates was determined. Results: We found that several of the Burkholderia strains were shared between patients. Ten of the 12 isolates were highly susceptible to HCS killing. Four of nine (44%) patients had cloaking antibodies that protected their cognate strain from serum killing. Depleting cloaking antibodies from patient serum restored HCS killing of Burkholderia isolates. Discussion: Cloaking antibodies are prevalent in patients with Burkholderia pulmonary infection and protect these strains from serum killing. Removal of cloaking antibodies via plasmapheresis, as previously described for individuals with life-threatening Pseudomonas infection, may be a useful new strategy for those with serious and life-threatening Burkholderia infection. [ABSTRACT FROM AUTHOR]

Introduction: The Burkholderia cepacia complex (BCC) encompasses a group of at least 22 genetically distinct gram-negatives bacterial species ubiquitous in nature. Recognised as a group of genetically and phenotypically flexible species, the BCC inhabits diverse ecological niches causing both plant and human diseases. Comparative genomic analysis provides an in depth understanding into the population biology, phylogenetic relationship, and genomic architecture of species. Methods: Here, we genomically characterise Burkholderia anthina isolated from patients with chronic lung infections, an understudied pathogen within the Burkholderia cepacia complex. Results: We demonstrate that B. anthina is polyphyletic and constitutes two distinct evolutionary lineages. Core- and pan-genome analyses demonstrated substantial metabolic diversity, with B. anthina Clade I enriched in genes associated with microbial metabolism in diverse environments, including degradation of aromatic compounds and metabolism of xenobiotics, while B. anthina Clade II demonstrated an enhanced capability for siderophore biosynthesis. Discussion: Based on our phylogenetic and comparative genomic analyses, we suggest stratifying B. anthina to recognise a distinct species harbouring increased potential for iron metabolism via siderophore synthesis, for which we propose the name Burkholderia anthinoferum (sp. nov.). [ABSTRACT FROM AUTHOR]

Background and Objective: Neutrophil elastase (NE), is an important host defence against lung pathogens. Maintaining a homeostatic balance between proteases such as NE and anti‐proteases such as secretory leukocyte protease inhibitor (SLPI), is important to prevent tissue damage. In the cystic fibrosis (CF) lung, elevated protease levels and impaired anti‐protease defences contribute to tissue destruction. Methods: We assessed lung function and sputum SLPI and NE levels from Pseudomonas aeruginosa infected and non‐infected CF patients (median age 20 years at recruitment) during different phases of clinical disease. Healthy, never smokers served as healthy controls (HC). Sputum total cell counts (TCC) and colony forming units of P. aeruginosa were also determined in each sputum sample. Results: Compared to HC, sputum SLPI was significantly reduced and NE increased in all CF subjects whether infected with P. aeruginosa or not, but the presence of P. aeruginosa worsened these parameters. Females with chronic P. aeruginosa infection had significantly lower sputum SLPI levels than males (p < 0.001). Higher sputum SLPI levels were associated with a significantly reduced rate of longitudinal decline in FEV1% predicted (p < 0.05). Antibiotic treatment in P. aeruginosa‐infected patients significantly decreased sputum TCC and increased SLPI levels, which positively correlated with improved lung function. Conclusion: Airway SLPI is deficient in CF, which appears more marked in P. aeruginosa‐infected female patients. Importantly, a reduced anti‐protease to protease ratio is associated with accelerated lung function decline. Treatment of an exacerbation is accompanied by partial recovery of anti‐protease defences and significant improvement in lung function, an important clinical outcome. Cystic fibrosis (CF) patients have impaired lung proteases and maintaining anti‐protease: protease ratios is crucial in preventing tissue damage. Secretory leukocyte protease inhibitor (SLPI) is significantly reduced and neutrophil elastase increased in P. aeruginosa‐infected female patients with CF; correlating with lung function decline. Antibiotic treatment restored SLPI levels and improved lung function. See relatedEditorial [ABSTRACT FROM AUTHOR]

Glucose-6-phosphatase-α (G6Pase-α) catalyzes the hydrolysis of glucose-6-phosphate to glucose and functions as a key regulator in maintaining blood glucose homeostasis. Deficiency in G6Pase-α causes glycogen storage disease 1a (GSD1a), an inherited disorder characterized by life-threatening hypoglycemia and other long-term complications. We have developed a potential mRNA-based therapy for GSD1a and demonstrated that a human G6Pase-α (hG6Pase-α) variant harboring a single serine (S) to cysteine (C) substitution at the amino acid site 298 (S298C) had > twofold increase in protein expression, resulting in improved in vivo efficacy. Here, we sought to investigate the mechanisms contributing to the increased expression of the S298C variant. Mutagenesis of hG6Pase-α identified distinct protein variants at the 298 amino acid position with substantial reduction in protein expression in cultured cells. Kinetic analysis of expression and subcellular localization in mammalian cells, combined with cell-free in vitro translation assays, revealed that altered protein expression stemmed from differences in cellular protein stability rather than biosynthetic rates. Site-specific mutagenesis studies targeting other cysteines of the hG6Pase-α S298C variant suggest the observed improvements in stability are not due to additional disulfide bond formation. The glycosylation at Asparagine (N)-96 is critical in maintaining enzymatic activity and mutations at position 298 mainly affected glycosylated forms of hG6Pase-α. Finally, proteasome inhibition by lactacystin improved expression levels of unstable hG6Pase-α variants. Taken together, these data uncover a critical role for a single amino acid substitution impacting the stability of G6Pase-α and provide insights into the molecular genetics of GSD1a and protein engineering for therapeutic development. [ABSTRACT FROM AUTHOR]

Background: Defective chloride transport in airway epithelial cells (AECs) and the associated lung disease are the main causes of morbidity and early mortality in cystic fibrosis (CF). Abnormal airway iron homeostasis and the presence of lipid peroxidation products, indicative of oxidative stress, are features of CF lung disease. Results: Here, we report that CF AECs (IB3-1) are susceptible to ferroptosis, a type of cell death associated with iron accumulation and lipid peroxidation. Compared to isogenic CFTR corrected cells (C38), the IB3-1 cells showed increased susceptibility to cell death upon exposure to iron in the form of ferric ammonium citrate (FAC) and the ferroptosis inducer, erastin. This phenotype was accompanied by accumulation of intracellular ferrous iron and lipid peroxides and the extracellular release of malondialdehyde, all indicative of redox stress, and increased levels of lactate dehydrogenase in the culture supernatant, indicating enhanced cell injury. The ferric iron chelator deferoxamine (DFO) and the lipophilic antioxidant ferrostatin-1 inhibited FAC and erastin induced ferroptosis in IB3-1 cells. Glutathione peroxidase 4 (GPX4) expression was decreased in IB3-1 cells treated with FAC and erastin, but was unchanged in C38 AECs. Necroptosis appeared to be involved in the enhanced susceptibility of IB3-1 AECs to ferroptosis, as evidenced by partial cell death rescue with necroptosis inhibitors and enhanced mixed lineage kinase domain-like (MLKL) localisation to the plasma membrane. Conclusion: These studies suggest that the increased susceptibility of CF AECs to ferroptosis is linked to abnormal intracellular ferrous iron accumulation and reduced antioxidant defences. In addition, the process of ferroptotic cell death in CF AECs does not appear to be a single entity and for the first time we describe necroptosis as a potential contributory factor. Iron chelation and antioxidant treatments may be promising therapeutic interventions in cystic fibrosis. [ABSTRACT FROM AUTHOR]

Developing an effective mRNA therapeutic often requires maximizing protein output per delivered mRNA molecule. We previously found that coding sequence (CDS) design can substantially affect protein output, with mRNA variants containing more optimal codons and higher secondary structure yielding the highest protein outputs due to their slow rates of mRNA decay. Here, we demonstrate that CDS-dependent differences in translation initiation and elongation rates lead to differences in translation- and deadenylation-dependent mRNA decay rates, thus explaining the effect of CDS on mRNA half-life. Surprisingly, the most stable and highest-expressing mRNAs in our test set have modest initiation/elongation rates and ribosome loads, leading to minimal translation-dependent mRNA decay. These findings are of potential interest for optimization of protein output from therapeutic mRNAs, which may be achieved by attenuating rather than maximizing ribosome load. [Display omitted] • Exogenously delivered mRNAs undergo translation-dependent decay through deadenylation • Nonoptimal codons lead to slow elongation, high ribosome load, and fast mRNA decay • mRNAs with fast initiation rates have high ribosome loads and fast mRNA decay • The most stable mRNAs are those with optimal codons and moderate ribosome loads Bicknell et al. demonstrate that exogenously delivered mRNAs are degraded in a translation-dependent manner at a rate that correlates with ribosome load. ORF sequences leading to high ribosome load cause faster translation-dependent decay. The most stable mRNA sequences are those with the fewest ribosomes due to slower rates of translation initiation. [ABSTRACT FROM AUTHOR]

Coal mine lung dust disease (CMDLD) and artificial stone (AS) silicosis are preventable diseases which have occurred in serious outbreaks in Australia recently. This has prompted a TSANZ review of Australia's approach to respiratory periodic health surveillance. While regulating respirable dust exposure remains the foundation of primary and secondary prevention, identification of workers with early disease assists with control of further exposure, and with the aims of preserving lung function and decreasing respiratory morbidity in those affected. Prompt detection of an abnormality also allows for ongoing respiratory specialist clinical management. This review outlines a medical framework for improvements in respiratory surveillance to detect CMDLD and AS silicosis in Australia. This includes appropriate referral, improved data collection and interpretation, enhanced surveillance, the establishment of a nationwide Occupational Lung Disease Registry and an independent advisory group. These measures are designed to improve health outcomes for workers in the coal mining, AS and other dust‐exposed and mining industries. [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF) is a common life‐limiting genetic condition. As the disease progresses access to specialist tertiary multi‐disciplinary care services may become necessary. For patients living in regional/remote Australia, accessing such services may be a challenge. Here, we describe long‐term outcomes for CF patients according to their access to specialist CF centre care in childhood. [ABSTRACT FROM AUTHOR]

Messenger RNAs (mRNAs) encode information in both their primary sequence and their higher order structure. The independent contributions of factors like codon usage and secondary structure to regulating protein expression are difficult to establish as they are often highly correlated in endogenous sequences. Here, we used 2 approaches, global inclusion of modified nucleotides and rational sequence design of exogenously delivered constructs, to understand the role of mRNA secondary structure independent from codon usage. Unexpectedly, highly expressed mRNAs contained a highly structured coding sequence (CDS). Modified nucleotides that stabilize mRNA secondary structure enabled high expression across a wide variety of primary sequences. Using a set of eGFP mRNAs with independently altered codon usage and CDS structure, we find that the structure of the CDS regulates protein expression through changes in functional mRNA half-life (i.e., mRNA being actively translated). This work highlights an underappreciated role of mRNA secondary structure in the regulation of mRNA stability. [ABSTRACT FROM AUTHOR]

The ability to predict the impact of cis-regulatory sequences on gene expression would facilitate discovery in fundamental and applied biology. Here we combine polysome profiling of a library of 280,000 randomized 5′ untranslated regions (UTRs) with deep learning to build a predictive model that relates human 5′ UTR sequence to translation. Together with a genetic algorithm, we use the model to engineer new 5′ UTRs that accurately direct specified levels of ribosome loading, providing the ability to tune sequences for optimal protein expression. We show that the same approach can be extended to chemically modified RNA, an important feature for applications in mRNA therapeutics and synthetic biology. We test 35,212 truncated human 5′ UTRs and 3,577 naturally occurring variants and show that the model predicts ribosome loading of these sequences. Finally, we provide evidence of 45 single-nucleotide variants (SNVs) associated with human diseases that substantially change ribosome loading and thus may represent a molecular basis for disease. Ribosome loading is predictably controlled through design of 5′ UTR sequences. [ABSTRACT FROM AUTHOR]

The increasing global incidence and prevalence of non-tuberculous mycobacteria (NTM) infection is of growing concern. New evidence of person-to-person transmission of multidrug-resistant NTM adds to the global concern. The reason why certain individuals are at risk of NTM infections is unknown. Using high definition flow cytometry, we studied the immune profiles of two groups that are at risk of Mycobacterium abscessus complex infection and matched controls. The first group was cystic fibrosis (CF) patients and the second group was elderly individuals. CF individuals with active M. abscessus complex infection or a history of M. abscessus complex infection exhibited a unique surface T cell phenotype with a marked global deficiency in TNFα production during mitogen stimulation. Importantly, immune-based signatures were identified that appeared to predict at baseline the subset of CF individuals who were at risk of M. abscessus complex infection. In contrast, elderly individuals with M. abscessus complex infection exhibited a separate T cell phenotype underlined by the presence of exhaustion markers and dysregulation in type 1 cytokine release during mitogen stimulation. Collectively, these data suggest an association between T cell signatures and individuals at risk of M. abscessus complex infection, however, validation of these immune anomalies as robust biomarkers will require analysis on larger patient cohorts. [ABSTRACT FROM AUTHOR]

The effectiveness of systemic-constructivist couple therapy (SCCT) in improving the relationship adjustment of South Asian Canadian couples in ways that attend to their culture was evaluated. The SCCT interventions engage partners in reflexive processing of both their own and their partner's ways of construing, and the reciprocity between these two. A core change mechanism of SCCT, couple identity ("we-ness"), that connotes the ability for thinking and experiencing relationally, was coded from verbatim transcripts of partners' within-session dialogue. As predicted, South Asian partners' relationship adjustment improved significantly from the first to final session of SCCT, and concurrent increases in each partner's couple identity mediated such improvements. The implications for considering culture and couple identity in couple therapy are discussed. Video Abstract is found in the online version of the article. [ABSTRACT FROM AUTHOR]

Phosphorylation of eukaryotic initiation factor 2κ (eIF2κ) controls transcriptome-wide changes in mRNA translation in stressed cells. While phosphorylated eIF2κ (P-eIF2κ) attenuates global protein synthesis, mRNAs encoding stress proteins are more efficiently translated. Two eIF2κ phosphatases, containing GADD34 and CReP, catalyze P-eIF2κ dephosphorylation. The current view of GADD34, whose transcription is stress induced, is that it functions in a feedback loop to resolve cell stress. In contrast, CReP, which is constitutively expressed, controls basal P-eIF2κ levels in unstressed cells. Our studies show that GADD34 drives substantial changes inmRNAtranslation in unstressed cells, particularly targeting the secretome. Following activation of the unfolded protein response (UPR), rapid translation of GADD34mRNAoccurs and GADD34 is essential for UPR progression. In the absence of GADD34, eIF2κphosphorylation is persistently enhanced and the UPR translational program is significantly attenuated. This "stalled" UPR is relieved by the subsequent activation of compensatory mechanisms that include AKT-mediated suppression of PKR-like kinase (PERK) and increased expression of CReP mRNA, partially restoring protein synthesis. Our studies highlight the coordinate regulation of UPR by the GADD34- and CReP-containing eIF2κphosphatases to control cell viability. [ABSTRACT FROM AUTHOR]

Background: People with cystic fibrosis (CF) may work in healthcare settings risking nosocomial pathogen acquisition. The aim of this study was to determine the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infection in adult healthcare workers with CF (HCWcf).Methods: Data was collected in this observational study on MRSA acquisition from 405 CF patients attending an adult CF centre in Australia between 2001-2012. Demographic and clinical characteristics were compared between HCWcf and non-HCWcf. A sub-analysis was subsequently performed to compare demographic and clinical characteristics between those patients (HCWcf versus non-HCWcf) that acquired MRSA. We also investigated rates of chronic MRSA infection and the outcome of eradication treatment in HCWcf.Results: A higher proportion of HCWcf acquired MRSA [n = 10/21] compared to non-HCWcf [n = 40/255] (P <0.001). The odds of MRSA acquisition were 8.4 (95 % CI, 3.0 - 23.4) times greater in HCWcf than non-HCWcf. HCWcf with MRSA were older (P = 0.02) and had better lung function (P = 0.009), yet hospitalisation rates were similar compared to non-HCWcf with MRSA. Chronic MRSA infection developed in 36/50 CF patients (HCWcf, n = 6; non-HCWcf, n = 30), with eradication therapy achieved in 5/6 (83 %) HCWcf.Conclusions: The rate of MRSA incidence was highest in HCWcf and the workplace is a possible source of acquisition. Vocational guidance should include the potential for MRSA acquisition for CF patients considering healthcare professions. [ABSTRACT FROM AUTHOR]

Background and objective In cystic fibrosis ( CF), chronic P seudomonas aeruginosa infection is associated with increased morbidity, antibiotic treatments and mortality. By linking Australian CF registry data with a national microbiological data set, we examined the association between where treatment was delivered, its intensity and P. aeruginosa antibiotic resistance. Methods Sputa were collected from paediatric and adult CF patients attending 18 Australian CF centres. P. aeruginosa antibiotic susceptibilities determined by local laboratories were correlated with clinical characteristics, treatment intensity and infection with strains commonly shared among Australian CF patients. Between-centre differences in treatment and antibiotic resistance were also compared. Results Large variations in antibiotic usage, maintenance treatment practices and multi-antibiotic resistant P. aeruginosa ( MARPA) prevalence exist between Australian CF centres, although the overall proportions of MARPA isolates were similar in paediatric and adult centres (31% vs 35%, P = 0.29). Among paediatric centres, MARPA correlated with intravenous antibiotic usage and the Australian state where treatment was delivered, while azithromycin, reduced lung function and treating state predicted intravenous antibiotic usage. In adult centres, body mass index ( BMI) and treating state were associated with MARPA, while intravenous antibiotic use was predicted by gender, BMI, dornase-alpha, azithromycin, lung function and treating state. In adults, P. aeruginosa strains AUST-01 and AUST-02 independently predicted intravenous antibiotic usage. Conclusion Increased treatment intensity in paediatric centres and the Australian state where treatment was received are both associated with greater risk of MARPA, but not worse clinical outcomes. [ABSTRACT FROM AUTHOR]

Background: Several cases of Burkholderia pseudomallei infection in CF have been previously reported. We aimed to identify all cases globally, risk factors for acquisition, clinical consequences, and optimal treatment strategies.Methods: We performed a literature search to identify all published cases of B. pseudomallei infection in CF. In addition we hand-searched respiratory journals, and contacted experts in infectious diseases and CF around the world. Supervising clinicians for identified cases were contacted and contemporaneous clinical data was requested.Results: 25 culture-confirmed cases were identified. The median age at acquisition was 21 years, mean FEV1 % predicted was 60 %, and mean BMI was 19.5 kg/m(2). The location of acquisition was northern Australia or south-east Asia for most. 19 patients (76 %) developed chronic infection, which was usually associated with clinical decline. Successful eradication strategies included a minimum of two weeks of intravenous ceftazidime, followed by a consolidation phase with trimethoprim/sulfamethoxazole, and this resulted in a higher chance of success when instituted early. Three cases of lung transplantation have been recorded in the setting of chronic B. pseudomallei infection.Conclusion: Chronic carriage of B. pseudomallei in patients with CF appears common after infection, in contrast to the non-CF population. This is often associated with an accelerated clinical decline. Lung transplantation has been performed in select cases of chronic B. pseudomallei infection. [ABSTRACT FROM AUTHOR]

Pioneering electron microscopy studies defined two primary populations of ribosomes in eukaryotic cells: one freely dispersed through the cytoplasm and the other bound to the surface of the endoplasmic reticulum (ER). Subsequent investigations revealed a specialized function for each population, with secretory and integral membrane protein-encoding mRNAs translated on ER-bound ribosomes, and cytosolic protein synthesis was widely attributed to free ribosomes. Recent findings have challenged this view, and transcriptome-scale studies of mRNA distribution and translation have now demonstrated that ER-bound ribosomes also function in the translation of a large fraction of mRNAs that encode cytosolic proteins. These studies suggest a far more expansive role for the ER in transcriptome expression, where membrane and secretory protein synthesis represents one element of a multifaceted and dynamic contribution to post-transcriptional gene expression. [ABSTRACT FROM AUTHOR]

Bronchiectasis is a pathological diagnosis describing dilatation of the airways and is characterized by chronic lung sepsis. Bronchiectasis has multiple etiologies, but is usually considered in terms of whether it is due to the genetic disorder cystic fibrosis (CF) or secondary to other causes (non-CF bronchiectasis, NCFB). Inhaled antibiotics are used in bronchiectasis to suppress bacterial pathogens and reduce long-term lung function decline. The majority of the literature on inhaled antibiotics comes from studies on CF where the dominant bacterial pathogen in the airway is usually Pseudomonas aeruginosa. Thus, most aerosolized antibiotic regimens target this bacterium, but the emergence of molecular diagnostic methods has questioned this approach and more tailored strategies may need to be considered in CF based on the community composition of the lung microbiome. Similarly, the lung microbiome in NCFB has been found to be a complex polymicrobial one and the current practice of employing the same inhaled antibiotic regimes as are used in CF may no longer be appropriate inmany patients. In this article, the use of inhaled antibiotics in CF and NCFB is considered in the light of improved understanding of the lung microbiome and why more tailored therapy may be needed based on molecular identification of themicrobial pathogens present. The evidence for the use of currently available inhaled antibiotics and advances in inhaled drug packaging and delivery devices are discussed. Finally, the urgent need for prospective randomized clinical trials in CF and NCFB is highlighted and areas for future research identified. [ABSTRACT FROM AUTHOR]

People with cystic fibrosis (CF) have been reported to make lung T cell responses that are biased towards T helper (Th) 2 or Th17. We hypothesized that CF-related T cell regulatory defects could be detected by analyzing CD4+ lymphocyte subsets in peripheral blood. Peripheral blood mononuclear cells from 42 CF patients (6 months–53 years old) and 78 healthy controls (2–61 years old) were analyzed for Th1 (IFN-γ+), Th2 (IL-4+), Th17 (IL-17+), Treg (FOXP3+), IL-10+ and TGF-β+ CD4+ cells. We observed higher proportions of Treg, IL-10+ and TGF-β+ CD4+ cells in CF adults (≥ 18 years old), but not children/adolescents, compared with controls. Within the CF group, high TGF-β+% was associated with chronic Pseudomonas aeruginosa lung infection (p < 0.006). We observed no significant differences between control and CF groups in the proportions of Th1, Th2 or Th17 cells, and no association within the CF group of any subset with sex, CFTR genotype, or clinical exacerbation. However, high Th17% was strongly associated with poor lung function (FEV1 % predicted) (p = 0.0008), and this association was strongest when both lung function testing and blood sampling were performed within one week. Our results are consistent with reports of CF as a Th17 disease and suggest that peripheral blood Th17 levels may be a surrogate marker of lung function in CF. [ABSTRACT FROM AUTHOR]

Background: Primary defects in host immune responses have been hypothesised to contribute towards an inability of subjects with cystic fibrosis (CF) to effectively clear pulmonary infections. Innate T-lymphocytes provide rapid pathogen-specific responses prior to the development of classical MHC class I and II restricted T-cell responses and are essential to the initial control of pulmonary infection. We aimed to examine the relationship between peripheral blood lymphocyte phenotype and clinical outcomes in adults with CF. Methods: We studied 41 subjects with CF and 22, age matched, non-smoking healthy control subjects. Lymphocytes were extracted from peripheral blood samples and phenotyped by flow-cytometry. Lymphocyte phenotype was correlated with sputum microbiology and clinical parameters. Results: In comparison to healthy control subjects, mucosal associated invariant T (MAIT)-lymphocytes were significantly reduced in the peripheral blood of subjects with CF (1.1% versus 2.0% of T-lymphocytes, P = 0.002). MAIT cell concentration was lowest in CF subjects infected with P. aeruginosa and in subjects receiving treatment for a pulmonary exacerbation. Furthermore a reduced MAIT cell concentration correlated with severity of lung disease. Conclusion: Reduced numbers of MAIT cells in subjects with CF were associated with P. aeruginosa pulmonary infection, pulmonary exacerbations and more severe lung disease. These findings provide the impetus for future studies examining the utility of MAIT cells in immunotherapies and vaccine development. Longitudinal studies of MAIT cells as biomarkers of CF pulmonary infection are awaited. [ABSTRACT FROM AUTHOR]

ICT use in cystic fibrosis management provides an alternative means of information supply to individuals, families, health care professionals and other stakeholders. The purpose of this paper is to present the evolution of a series of projects culminating in a project that translates the previous research into practice. In this paper the sequential nature of the projects will be detailed. The three projects explored are the Pathways Home for Respiratory Illness Project (Pathways Home), Enhancing Self-Efficacy for Self-Management in People with Cystic Fibrosis and the Tasmanian Community Fund Project (myCF pilot). [ABSTRACT FROM AUTHOR]

Nearly thirty percent of all newly synthesized polypeptides are targeted for rapid proteasome-mediated degradation. These rapidly degraded polypeptides (RDPs) are a source of antigenic substrates for the MHC class I presentation pathway, allowing for immunosurveillance of newly synthesized proteins by cytotoxic T lymphocytes. Despite the recognized role of RDPs in MHC I presentation, it remains unclear what molecular characteristics distinguish RDPs from their more stable counterparts. It has been proposed that premature translational termination products may constitute a form of RDP; indeed, in prokaryotes translational drop-off products are normal by-products of protein synthesis and are subsequently rapidly degraded. To study the cellular fate of premature termination products, we used the antibiotic puromycin as a means to experimentally manipulate prematurely terminated polypeptide production in human cells. At low concentrations, puromycin enhanced flux into rapidly degraded polypeptide pools, with small polypeptides being markedly more labile then high molecular weight puromycin adducts. Immunoprecipitation experiments using anti-puromycin antisera demonstrated that the majority of peptidyl-puromycins are rapidly degraded in a proteasome-dependent manner. Low concentrations of puromycin increased the recovery of cell surface MHC I-peptide complexes, indicating that prematurely terminated polypeptides can be processed for presentation via the MHC I pathway. In the continued presence of puromycin, however, MHC I export to the cell surface was inhibited, coincident with the accumulation of polyubiquitinated proteins. The time- and dose-dependent effects of puromycin suggest that the pool of peptidyl-puromycin adducts differ in their targeting to various proteolytic pathways that, in turn, differ in the efficiency with which they access the MHC I presentation machinery. These studies highlight the diversity of cellular proteolytic pathways necessary for the metabolism and immunosurveillance of prematurely terminated polypeptides that are, by their nature, highly heterogeneous. [ABSTRACT FROM AUTHOR]

The article focuses on a study that was conducted to investigate exposure to cigarette smoke (CS) with increased risk of pneumococcal infection. It further determines whether CS stimulates pneumococcal adhesion to airway cells. The results of the study indicate that exposure of airway cells to cigarette smoke extract (CSE) in vitro resulted in cell contraction and cytoplasmic vacuolation.

Soltani A, Muller H K, Sohal S S, Reid D W, Weston S, Wood-Baker R & Walters E H (2012) Histopathology 60, 964-970 Distinctive characteristics of bronchial reticular basement membrane and vessel remodelling in chronic obstructive pulmonary disease (COPD) and in asthma: they are not the same disease Aims: This study compared reticular basement membrane (Rbm) and vascular remodelling within the bronchial mucosa of subjects with chronic obstructive pulmonary disease (COPD) with those from patients with asthma, to test the 'Dutch hypothesis' of whether these are essentially the same or different pathological conditions. Methods and results: Bronchoscopic biopsies were stained with anti-collagen IV antibody; 18 current smoking COPD, 10 symptomatic asthmatics and 13 healthy non-smoking controls were studied. The Rbm in COPD was fragmented, non-homogeneous, variable in thickness and hypervascular, whereas in asthma the Rbm was compact and homogeneous with no evidence of increased vascularity compared to controls. Length of Rbm splitting presented as percentage of Rbm length was used to measure fragmentation; it was greater in COPD than in controls and asthmatics [median (range) 20.7% (0.4-68.5) versus 5.3% (0.0-21.7) versus 1.5% (0.0-15.1), P < 0.001]. The number of Rbm vessels/mm Rbm [median (range) 10.1 (1.6-23.0) versus 4.5 (0.0-26.4) versus 4.4 (0.4-8.1), P < 0.01] and area of Rbm vessels, μm2/mm Rbm [median (range) 953 (115-2456) versus 462 (0-3263) versus 426 (32-2216), P < 0.05] was also increased in COPD compared to normal subjects and asthmatics. Conclusions: The characteristics of Rbm remodelling are quite different in asthma and COPD. [ABSTRACT FROM AUTHOR]

Objectives. In Aboriginal and Torres Strait Islander peoples in Queensland, to (a) determine the disease burden of common chronic lung diseases and (b) identify areas of need with respect to lung health services. Methods. Literature reviews and analyses of hospitalisation and mortality data were used to describe disease epidemiology and available programs and services. Key stakeholder interviews and an online survey of health professionals were used to evaluate lung health services across the state and to identify services, needs and gaps. Results. Morbidity and mortality from respiratory diseases in the Indigenous population is substantially higher than the non-Indigenous population across all age groups and regions. There are inadequate clinical services and resources to address disease prevention, detection, intervention and management in an evidence-based and culturally acceptable fashion. There is a lack of culturally appropriate educational resources and management programs, insufficient access to appropriately engaged Indigenous health professionals, a lack of multi-disciplinary specialist outreach teams, fragmented information systems and inadequate coordination of care. Conclusions. Major initiatives are required at all levels of the healthcare system to adequately address service provision for Indigenous Queenslanders with lung diseases, including high quality research to investigate the causes for poor lung health, which are likely to be multifactorial. INSET: What is known about the topic?. [ABSTRACT FROM AUTHOR]

The article discusses a research study that seeks to assess mortality trends among people with cystic fibrosis (CF) in Australia for the period, 1979-2005. Summary mortality data was sourced from the General Record of Incidence of Mortality (GRIM) augmented with information from Australian transplant centers on lung transplantation among CF patients for 1989-2005. Results point to a substantial change in the pattern of CF mortality in Australia and an increase in survival rates since 1979.

The article discusses consensus recommendations for managing chronic suppurative lung disease (CSLD) and bronchiectasis, that were developed at a multidisciplinary workshop by the Thoracic Society of Australia and New Zealand (TSANZ) and the Australian Lung Foundation (ALF). CLSD or bronchiectasis is suspected when chronic wet cough persists after eight weeks. A high-resolution computer tomography scan of the chest is required for the diagnosis of bronchiectasis.

Background and objective: Haemochromatosis ( HFE) mutations increase the risk of bowel obstruction in cystic fibrosis (CF), but the impact on other disease manifestations is unknown. Methods: We determined the prevalence of HFE mutations (C282Y and H63D) in the Tasmanian CF population and assessed the relationship to systemic iron stores, Pseudomonas aeruginosa infection, lung disease severity and prevalence of diabetes. Results: DNA was obtained from 82 individuals (96% of the entire CF population); 19 (23.2%) were H63D heterozygotes, three (3.7%) were H63D homozygotes and two patients were compound C282Y/H63D (2.4%). Seven (8.5%) patients were heterozygous for the C282Y mutation. Overall, 31 (37.8%) patients carried a HFE mutation. CF patients possessing HFE mutations had significantly better iron stores than non-carriers ( P < 0.05). The mean slopes of annual decline in FEV1 and FVC % predicted were significantly steeper in HFE carriers compared with non-carriers ( P < 0.01). Patients with HFE mutations were more likely to have had childhood bowel obstruction (RR 2.44, 95% CI: 1.04–5.74, P < 0.05). Diabetes was more common in HFE carriers (RR 2.96, 95% CI: 0.99–8.8, P = 0.05), but this effect attenuated when corrected for age (RR 2.89, 95% CI: 0.91–9.21, P = 0.07). Conclusions: HFE gene mutations modify disease severity in CF, through probable effects on iron homeostasis. [ABSTRACT FROM AUTHOR]

Background: Little is known about airway remodelling in bronchial biopsies (BB) in smokers and chronic obstructive pulmonary disease (COPD). We conducted an initial pilot study comparing BB from COPD patients with nonsmoking controls. This pilot study suggested the presence of reticular basement membrane (Rbm) fragmentation and altered vessel distribution in COPD. Methods: To determine whether Rbm fragmentation and altered vessel distribution in BB were specific for COPD we designed a cross-sectional study and stained BB from 19 current smokers and 14 ex-smokers with mild to moderate COPD and compared these to 15 current smokers with normal lung function and 17 healthy and nonsmoking subjects. Results: Thickness of the Rbm was not significantly different between groups; although in COPD this parameter was quite variable. The Rbm showed fragmentation and splitting in both current smoking groups and ex-smoker COPD compared with healthy nonsmokers (p < 0.02); smoking and COPD seemed to have additive effects. Rbm fragmentation correlated with smoking history in COPD but not with age. There were more vessels in the Rbm and fewer vessels in the lamina propria in current smokers compared to healthy nonsmokers (p < 0.05). The number of vessels staining for vascular endothelial growth factor (VEGF) in the Rbm was higher in both current smoker groups and ex-smoker COPD compared to healthy nonsmokers (p < 0.004). In current smoker COPD VEGF vessel staining correlated with FEV1% predicted (r = 0.61, p < 0.02). Conclusions: Airway remodelling in smokers and mild to moderate COPD is associated with fragmentation of the Rbm and altered distribution of vessels in the airway wall. Rbm fragmentation was also present to as great an extent in ex-smokers with COPD. These characteristics may have potential physiological consequences. [ABSTRACT FROM AUTHOR]

Background and objective: There are few data on the short-term natural history of airway inflammation during severe episodes of acute exacerbation of COPD (AECOPD). An observational study was performed to determine how rapidly conventional treatment improves airway inflammation in patients admitted to hospital with AECOPD. Methods: Twenty-four consecutive patients with AECOPD were recruited and changes in sputum inflammatory indices were assessed after 2 and 4 days of treatment. The primary end-points included presence of bacteria and viruses, changes in sputum total cell counts (TCC) and polymorphonuclear leukocyte (PMN) differential counts, and levels of secretory leukocyte protease inhibitor (SLPI), IL-8 and TNF-α. Results: All patients received oral corticosteroids and 17 (71%) were also treated with oral antibiotics. A bacterial or viral pathogen was isolated from 12 patients (50%), and Aspergillus fumigatus was isolated from one. A positive bacterial culture was associated with increased sputum TCC and PMN count ( P < 0.05), as well as higher levels of IL-8 and TNF-α ( P < 0.05), and a trend towards lower sputum SLPI levels ( P = 0.06). Sputum PMN numbers fell by 70% within the first 48 h of admission ( P < 0.05), accompanied by an increase in sputum SLPI ( P < 0.001) and reductions in the levels of TNF-α ( P < 0.005) and IL-8 ( P = 0.06), with no further significant change at 4 days. Conclusions: Conventional treatment for severe AECOPD is associated with rapid reduction of neutrophilic inflammation and improvement in anti-protease defences. [ABSTRACT FROM AUTHOR]

Fourier transform infrared (FTIR) spectroscopy provides a (bio)chemical snapshot of the sample, and was recently used in proof-of-concept cohort studies for COVID-19 saliva screening. However, the biological basis of the proposed technology has not been established. To investigate underlying pathophysiology, we conducted controlled infection experiments on Vero E6 cells in vitro and K18-hACE2 mice in vivo. Potentially infectious culture supernatant or mouse oral lavage samples were treated with ethanol or 75% (v/v) Trizol for attenuated total reflectance (ATR)-FTIR spectroscopy and proteomics, or RT-PCR, respectively. Controlled infection with UV-inactivated SARS-CoV-2 elicited strong biochemical changes in culture supernatant/oral lavage despite a lack of viral replication, determined by RT-PCR or a cell culture infectious dose 50% assay. Nevertheless, SARS-CoV-2 infection induced additional FTIR signals over UV-inactivated SARS-CoV-2 infection in both cell and mouse models, which correspond to aggregated proteins and RNA. Proteomics of mouse oral lavage revealed increased secretion of kallikreins and immune modulatory proteins. Next, we collected saliva from a cohort of human participants (n = 104) and developed a predictive model for COVID-19 using partial least squares discriminant analysis. While high sensitivity of 93.48% was achieved through leave-one-out cross-validation, COVID-19 patients testing negative on follow-up on the day of saliva sampling using RT-PCR was poorly predicted in this model. Importantly, COVID-19 vaccination did not lead to the misclassification of COVID-19 negatives. Finally, meta-analysis revealed that SARS-CoV-2 induced increases in the amide II band in all arms of this study and in recently published cohort studies, indicative of altered β-sheet structures in secreted proteins. In conclusion, this study reveals a consistent secretory pathophysiological response to SARS-CoV-2, as well as a simple, robust method for COVID-19 saliva screening using ATR-FTIR. [ABSTRACT FROM AUTHOR]

Background and objective: Bronchodilator reversibility (BDR) is common in smoking-related COPD, but the airway pathology underlying this has not been described. In particular, it is not known whether BDR is associated with underlying airway eosinophilia and whether BDR is predictive of a better response to inhaled corticosteroid (ICS) treatment. Methods: A double-blind, placebo-controlled, randomized 2 : 1 study of fluticasone propionate (FP), 500 µg twice daily versus placebo over 6 months was performed in subjects with mild to moderate COPD. Subjects with a clinical history of asthma were excluded, but not on BDR criteria alone. Induced sputum, BAL and endobronchial biopsies (EBB) were performed in 36 subjects at baseline, and 30 of these provided a second full set of samples (FP, n = 19; placebo, n = 11). Results: Baseline BDR was not related to airway eosinophilia and did not predict response to ICS. Post-bronchodilator FEV1 increased in the FP group compared with the placebo group ( P = 0.05), and there were within-treatment group reductions in total symptom scores with FP ( P < 0.05). Compared with placebo, FP reduced macrophage numbers but increased neutrophil numbers in EBB ( P = 0.01 and P = 0.003, respectively). BAL neutrophil and epithelial cell numbers were also reduced with FP ( P = 0.03 for both). There were within-treatment group reductions in the numbers of EBB mast cells and CD8+ve lymphocytes with FP ( P = 0.007). Conclusions: BDR was not related to any particular inflammatory phenotype or any clinical or anti-inflammatory response to ICS in these subjects with mild to moderate COPD. [ABSTRACT FROM AUTHOR]

Background and objective: Clonal strains of Pseudomonas aeruginosa have been identified in large cystic fibrosis (CF) centres. Whether such strains are more virulent or whether cross-infection between patients explains their widespread prevalence is unknown. This study described the epidemiology of P. aeruginosa infection in CF patients in Tasmania, Australia, an area with a high CF birth incidence. Patients in Tasmania are geographically dispersed and when this study was conducted (2003) there was no central CF clinic, with patients receiving treatment in regional hospitals. Methods: P. aeruginosa isolates from CF adults aged 15 years and over in Tasmania were genotyped using random amplified polymorphic DNA (RAPD)-PCR and clonal strains confirmed with pulsed field gel electrophoresis. Results: Airway samples were obtained from 41 patients (82% of the adult CF population). P. aeruginosa was isolated from 34 patients and nine (26%) of these individuals harboured P. aeruginosa strains with identical RAPD-PCR and pulsed field gel electrophoresis patterns (Australian Epidemic Strain III – AES III). AES III was isolated from patients in all regions of Tasmania and was distinct from the epidemic CF strains described on mainland Australia (AES I and II). The possible link between CF adults infected with AES III was attendance at family camps more than 12 years previously. Patients harbouring AES III had suffered significantly more exacerbations requiring hospitalisation during the 2 years prior to the study compared with patients infected with unique strains ( P < 0.01). AES III displayed increased multi-antibiotic resistance compared with other strains ( P < 0.001). Conclusions: Clonal strains of P. aeruginosa may arise even in isolated CF populations. The increased exacerbation rate in patients infected with AES III and its antibiotic resistance profile strongly suggest increased virulence. [ABSTRACT FROM AUTHOR]

Background: The potential for tolerance to develop to zafirlukast, a cysteinyl leukotriene (CysLT) receptor antagonist (LRA) in persistent asthma, has not been specifically examined. Objective: To look for any evidence of tolerance and potential for short-term clinical worsening on LRA withdrawal. Outcome measures included changes in; airway hyperresponsiveness to inhaled methacholine (PD20FEV1), daily symptoms and peak expiratory flows (PEF), sputum and blood cell profiles, sputum CysLT and prostaglandin (PG)E2 and exhaled nitric oxide (eNO) levels. Methods: A double blind, placebo-controlled study of zafirlukast, 20 mg twice daily over 12 weeks in 21 asthmatics taking β2-agonists only (Group I), and 24 subjects treated with ICS (Group II). Results: In Group I, zafirlukast significantly improved morning PEF and FEV1compared to placebo (p < 0.01), and reduced morning waking with asthma from baseline after two weeks (p < 0.05). Similarly in Group II, FEV1 improved compared to placebo (p < 0.05), and there were early within-treatment group improvements in morning PEF, β2-agonist use and asthma severity scores (p < 0.05). However, most improvements with zafirlukast in Group I and to a lesser extent in Group II deteriorated toward baseline values over 12 weeks. In both groups, one week following zafirlukast withdrawal there were significant deteriorations in morning and evening PEFs and FEV1 compared with placebo (p ≤ 0.05) and increased nocturnal awakenings in Group II (p < 0.05). There were no changes in PD20FEV1, sputum CysLT concentrations or exhaled nitric oxide (eNO) levels. However, blood neutrophils significantly increased in both groups following zafirlukast withdrawal compared to placebo (p = 0.007). Conclusion: Tolerance appears to develop to zafirlukast and there is rebound clinical deterioration on drug withdrawal, accompanied by a blood neutrophilia. [ABSTRACT FROM AUTHOR]

Background and objective: In cystic fibrosis (CF) very few studies have assessed sputum 8-iso-PGF2α levels during pulmonary exacerbations as a direct measure of airway oxidative stress. The role of other lipid-derived inflammatory mediators, such as the cysteinyl leukotrienes (cys-LTs) and prostaglandin (PG)-E2, during exacerbations is also poorly defined and the effect of conventional antibiotic therapy on these components of the inflammatory process is unclear. Methods: Sputum 8-iso-PGF2α, total cys-LT and PGE2 levels were measured in 17 CF patients experiencing a pulmonary exacerbation and repeated analysis were performed in 15 of these patients after antibiotic treatment. Eight stable CF and nine healthy subjects provided control data. Results: Sputum 8-iso-PGF2α was significantly elevated in acute, but not stable CF patients versus healthy controls ( P < 0.001). Similarly, sputum cys-LT and PGE2 levels were increased in acute compared with stable CF patients and healthy controls ( P ≤ 0.001). Although substantially lower than in acute patients, sputum cys-LT levels in stable patients were also significantly higher than in normal controls ( P = 0.01). There were strong associations between cys-LT levels and sputum total cell counts, and blood neutrophils in acute patients ( r2 = 0.53, P = 0.001 and r2 = 0.33, P < 0.05, respectively). Overall in the CF patients, FEV1%predicted was strongly and negatively correlated with sputum 8-iso-PGF2α ( r2 = 0.34, P = 0.006), cys-LT ( r2 = 0.40, P = 0.002) and PGE2 ( r2 = 0.52, P < 0.001) levels. Antibiotic treatment reduced sputum total cell count ( P = 0.03), but did not affect 8-iso-PGF2α, cys-LT or PGE2 levels. Conclusions: CF exacerbations are characterized by increased oxidative stress and sputum concentrations of bioactive lipid mediators. Treatment does not modulate these aspects of inflammation and more targeted therapy needs further study. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa causes chronic infections in the lungs of cystic fibrosis (CF) individuals and remains the leading cause of morbidity and mortality associated with the disease. Biofilm growth and phenotypic diversification are factors thought to contribute to this organism's persistence. Most studies have focused on laboratory isolates such as strain PAO1, and there are relatively few reports characterizing the properties of CF strains, especially under decreased oxygen conditions such as occur in the CF lung. This study compared the phenotypic and functional properties of P. aeruginosa from chronically infected CF adults with those of strain PAO1 and other clinical non-CF isolates under aerobic and anaerobic culture conditions. The CF isolates overall displayed a reduced ability to form biofilms in standard in vitro short-term models. They also grew more slowly in culture, and exhibited decreased adherence to glass and decreased motilities (swimming, swarming and twitching). All of these characteristics were markedly accentuated by anaerobic growth conditions. Moreover, the CF strain phenotypes were not readily reversed by culture manipulations designed to encourage planktonic growth. The CF strains were thus inherently different from strain PAO1 and most of the other non-CF clinical P. aeruginosa isolates tested. In vitro models used to research CF isolate biofilm growth need to take the above properties of these strains into account. [ABSTRACT FROM AUTHOR]

Changes in partners' sense of self-in-relationship, which a systemicconstructivist couple therapy (SCCT) induced, led to robust improvement in satisfaction in 2 studies and a follow-up study. In each study, 13 referred couples completed measures of satisfaction, mutuality, similarities, and other-in-self construal pre-post 12 hours of SCCT. The authors reliably coded transcripts of 1st and final sessions for each partner's we-ness, the identity that each partner establishes in relationship to the other. Having met the criteria for the rigorous study of change in single group process-outcome design, changes in we-ness accompanied large posttherapy dyadic increments on all variables in each study. Therapeutic gains appeared at follow-up and correlated with increased weness obtained at end of therapy 2 years earlier. The authors raise theoretical implications for all types of couple therapies and explain clinical techniques. [ABSTRACT FROM AUTHOR]

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Exhaled nitric oxide continues to reflect airway hyperresponsiveness and disease activity in inhaled corticosteroid-treated adult asthmatic patients REID DW, JOHNS DP, FELTIS B, WARD C, WALTERS EH. Respirology 2003; 8: 479–486 Exhaled nitric oxide (eNO) has been used as a surrogate of airway inflammation in mild asthma. However, whether eNO levels reflect disease activity in symptomatic asthmatics receiving moderate doses of inhaled corticosteroid (ICS) is more uncertain. To examine the relationship between eNO levels, sputum and blood eosinophils (SpE and PbE), PD20 methacholine as a marker of airway hyperresponsiveness (AHR) and clinical status in 28 ICS-treated asthmatic subjects with persistent asthma compared to that in 25 symptomatic asthmatics managed with β2-agonists alone. As expected, eNO levels were normalized in ICS-treated subjects and significantly elevated in the β2-agonist only group ( P < 0.001). SpE, PbE and PD20M did not differ between asthmatic groups but FEV1 was significantly worse in ICS-treated subjects ( P < 0.01). Exhaled NO levels correlated with PbE within both asthmatic groups ( P < 0.005), but with SpE only in ICS-untreated subjects (r(s) = 0.6, P < 0.05). In contrast, PD20M was negatively correlated with eNO and PbE in ICS-treated subjects only (r(s) = − 0.4, r(s) = − 0.4, respectively, P < 0.05). SpE and PbE were strongly correlated in both asthmatic groups (r(s) = 0.8, r(s) = 0.7, respectively, P < 0.005). Exhaled NO levels, SpE and PbE were all positively associated with increased nocturnal awakenings ( P < 0.05) in ICS-treated subjects, but not in ICS-untreated subjects. In ICS-treated asthma, eNO reflects clinical activity, PbE and AHR but not eosinophilic airway inflammation. Exhaled NO levels are quantitatively and relationally different in asthmatic subjects treated with ICS and continue to have potential for use as a surrogate of asthma pathophysiology in this group. [ABSTRACT FROM AUTHOR]

Background: Iron deficiency (ID) is common in patients with cystic fibrosis (CF) and may be related to GI factors and chronic inflammation. Pseudomonas aeruginosa (PA) infection is predominantly responsible for chronic lung suppuration in patients with CF, but its survival is critically dependent on the availability of extracellular iron, which it obtains via highly efficient mechanisms.Objective: To determine whether ID in CF patients is directly related to the severity of suppurative lung disease.Design: We determined the iron status of 30 randomly selected adult CF patients (13 women) and assessed the relationship to lung disease severity and GI factors by determining their daily sputum volume, FEV(1) percent predicted, C-reactive protein (CRP) level, erythrocyte sedimentation rate, and degree of pancreatic supplementation. Additionally, we measured the sputum concentrations of iron and ferritin in a randomly selected subgroup of 13 of the 30 subjects.Setting: Adult CF Service in a tertiary-care center.Results: Seventy-four percent of subjects experienced ID (ie, serum iron levels < or = 12 micromol/L and/or transferrin saturation levels < or = 16%). There was no relationship found with the degree of pancreatic supplementation. The daily sputum volume was strongly associated with low serum iron levels, transferrin saturation, ferritin/CRP ratio, and FEV(1) percent predicted (p < 0.05). Serum iron levels and transferrin saturation were negatively related to CRP (r = -0.8 and r = -0.7, respectively; p < 0.01) and erythrocyte sedimentation rate (r = -0.5 and r = -0.4, respectively; p < 0.05). FEV(1) percent predicted was positively related to serum iron level (r = 0.5; p < 0.01), transferrin saturation (r = 0.4; p < 0.05), and ferritin/CRP ratio (r = 0.7; p < 0.05). Sputum iron concentration (median, 63 micromol/L; range, 17 to 134 micromol/L) and ferritin concentration (median, 5,038 microg/L; range, 894 to 6,982 microg/L) exceeded plasma levels and negatively correlated with FEV(1) percent predicted (r = -0.6 and r = -0.5, respectively; p < or = 0.05).Conclusion: In our CF patients, ID was directly related to the increased severity of suppurative lung disease but not to the degree of pancreatic insufficiency. Iron loss into the airway may contribute to ID and may facilitate PA infection. [ABSTRACT FROM AUTHOR]

Background: Iron deficiency (ID) is common in patients with cystic fibrosis (CF) and may be related to GI factors and chronic inflammation. Pseudomonas aeruginosa (PA) infection is predominantly responsible for chronic lung suppuration in patients with CF, but its survival is critically dependent on the availability of extracellular iron, which it obtains via highly efficient mechanisms. Objective: To determine whether ID in CF patients is directly related to the severity of suppurative lung disease. Design: We determined the iron status of 30 randomly selected adult CF patients (13 women) and assessed the relationship to lung disease severity and GI factors by determining their daily sputum volume, FEV[sub 1] percent predicted, C-reactive protein (CRP) level, erythrocyte sedimentation rate, and degree of pancreatic supplementation. Additionally, we measured the sputum concentrations of iron and ferritin in a randomly selected subgroup of 13 of the 30 subjects. Setting: Adult CF Service in a tertiary-care center. Results: Seventy-four percent of subjects experienced ID (ie, serum iron levels ≤ 12 µmol/L and/or transferrin saturation levels ≤ 16%). There was no relationship found with the degree of pancreatic supplementation. The daily sputum volume was strongly associated with low serum iron levels, transferrin saturation, ferritin/CRP ratio, and FEV[sub 1] percent predicted (p < 0.05). Serum iron levels and transferrin saturation were negatively related to CRP (r = -0.8 and r = -0.7, respectively; p < 0.01) and erythrocyte sedimentation rate (r = -0.5 and r = -0.4, respectively; p < 0.05). FEV[sub 1] percent predicted was positively related to serum iron level (r = 0.5; p < 0.01), transferrin saturation (r = 0.4; p < 0.05), and ferritin/CRP ratio (r = 0.7; p < 0.05). Sputum iron concentration (median, 63 µmol/L; range, 17 to 134 µmol/L) and ferritin concentration (median, 5,038 µg/L; range, 894 to 6,982 µg/L) exceeded plasma... [ABSTRACT FROM AUTHOR]

In this article, we critically review the epistemological transition from a modernist or first-order cybernetic approach in which subject-object dualism is implicitly assumed and enacted within the therapeutic relationship, to the current postmodern, second-order approach. Problems associated with both epistemological persuasions are examined. We propose a theoretical way out of the epistemological corner defined by a former naive realism, on the one hand, and the current potential for a nonfunctional relativism, on the other. This route is created through an integration of systemic and constructivist metatheory whereby therapist knowledge, as fallible as it may be, is afforded a rightful place within the therapy relationship. Moreover, participant-observation is considered a necessary extension to the postmodern emphasis on therapistreflexivitybecause it reinstates the importance of therapist knowledge (i.e., objectifications of family dynamics and experiences). It is suggested that the willingness to engage in the process of intersubjective meaning creation, guided by the therapist and the client, but driven by the client's own knowing and experiencing, is central to the success of therapy. [ABSTRACT FROM AUTHOR]

We examined the relationship between ratings of patient cooperation and neuropsychological test performance in a sample (N = 333) of dementing patients and normal controls. We also examined the stability of the relationship in a subset of this same sample (N = 299) who were retested a year later. All the correlation coefficients in both years were significant, with a median Pearson of .64 in year one and .725 in year two. The test-retest reliability for ratings of cooperativeness over the one-year time period (rated by different examiners) was also significant,r = .64 (p < .0001). This analysis indicates that cooperation plays a significant role in neuropsychological test performance and that ratings of cooperativeness are relatively stable over periods of up to a year in length. [ABSTRACT FROM PUBLISHER]