Cystic Fibrosis

Roadmap for an early gene therapy for cystic fibrosis airway disease.

Fri, 2017-10-06 07:42

Roadmap for an early gene therapy for cystic fibrosis airway disease.

Prenat Diagn. 2017 Oct 05;:

Authors: Carlon MS, Vidović D, Birket S

Abstract
Gene therapy provides a mutation-independent approach to treat or even cure CF airway disease. To develop a clinical candidate for CF gene therapy, a thorough examination of preclinical efficacy in relevant cell and animal models is a prerequisite. For a long time, the CF field was struggling with a lack of appropriate animal models for CF airway pathology. Since 2008, many different and complementary animal models have been generated that develop hallmarks of CF airway disease, including the CF pig, ferret and rat. With this, a new era has arisen that allows investigating the efficacy of gene therapy beyond molecular and electrophysiological end-points. Successful gene therapy most likely requires an appropriate time window. CF lung pathology progresses with age and therefore an early treatment would be beneficial to prevent irreversible damage. In that regard, newborn screening programs and prenatal diagnosis already provide a basis to facilitate future preventive gene-based treatment. If successful, gene therapy for CF airway disease would markedly reduce the treatment burden and improve life quality and life expectancy of CF patients.

PMID: 28981983 [PubMed - as supplied by publisher]

Categories: Literature Watch

Standard versus biofilm antimicrobial susceptibility testing to guide antibiotic therapy in cystic fibrosis.

Fri, 2017-10-06 07:42

Standard versus biofilm antimicrobial susceptibility testing to guide antibiotic therapy in cystic fibrosis.

Cochrane Database Syst Rev. 2017 Oct 05;10:CD009528

Authors: Waters V, Ratjen F

Abstract
BACKGROUND: The antibiotics used to treat pulmonary infections in people with cystic fibrosis are typically chosen based on the results of antimicrobial susceptibility testing performed on bacteria traditionally grown in a planktonic mode (grown in a liquid). However, there is considerable evidence to suggest that Pseudomonas aeruginosa actually grows in a biofilm (or slime layer) in the airways of people with cystic fibrosis with chronic pulmonary infections. Therefore, choosing antibiotics based on biofilm rather than conventional antimicrobial susceptibility testing could potentially improve response to treatment of Pseudomonas aeruginosa in people with cystic fibrosis. This is an update of a previously published Cochrane Review.
OBJECTIVES: To compare biofilm antimicrobial susceptibility testing-driven therapy to conventional antimicrobial susceptibility testing-driven therapy in the treatment of Pseudomonas aeruginosa infection in people with cystic fibrosis.
SEARCH METHODS: We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Most recent search: 19 June 2017.We also searched two ongoing trials registries and the reference lists of relevant articles and reviews. Most recent searches: 24 August 2017 and 05 September 2017.
SELECTION CRITERIA: Randomized controlled trials of antibiotic therapy based on biofilm antimicrobial susceptibility testing compared to antibiotic therapy based on conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infection in people with cystic fibrosis.
DATA COLLECTION AND ANALYSIS: Both authors independently selected trials, assessed their risk of bias and extracted data from eligible trials. Additionally, the review authors contacted the trial investigators to obtain further information. The quality of the evidence was assessed using the GRADE criteria.
MAIN RESULTS: The searches identified two multicentre, randomized, double-blind controlled clinical trials eligible for inclusion in the review with a total of 78 participants (adults and children); one trial was done in people who were clinically stable, the other in people experiencing pulmonary exacerbations. These trials prospectively assessed whether the use of biofilm antimicrobial susceptibility testing improved microbiological and clinical outcomes in participants with cystic fibrosis who were infected with Pseudomonas aeruginosa. The primary outcome was the change in sputum Pseudomonas aeruginosa density from the beginning to the end of antibiotic therapy.Although the intervention was shown to be safe, the data from these two trials did not provide evidence that biofilm susceptibility testing was superior to conventional susceptibility testing either in terms of microbiological or lung function outcomes. One of the trials also measured risk and time to subsequent exacerbation as well as quality of life measures and did not demonstrate any difference between groups in these outcomes. Both trials had an overall low risk of bias and the quality of the evidence using GRADE criteria was deemed to be moderate to high for the outcomes selected.
AUTHORS' CONCLUSIONS: The current evidence is insufficient to recommend choosing antibiotics based on biofilm antimicrobial susceptibility testing rather than conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infections in people with cystic fibrosis. Biofilm antimicrobial susceptibility testing may be more appropriate in the development of newer, more effective formulations of drugs which can then be tested in clinical trials.

PMID: 28981972 [PubMed - as supplied by publisher]

Categories: Literature Watch

The diagnosis of male infertility: an analysis of the evidence to support the development of global WHO guidance-challenges and future research opportunities.

Fri, 2017-10-06 07:42

The diagnosis of male infertility: an analysis of the evidence to support the development of global WHO guidance-challenges and future research opportunities.

Hum Reprod Update. 2017 Jul 19;:1-21

Authors: Barratt CLR, Björndahl L, De Jonge CJ, Lamb DJ, Osorio Martini F, McLachlan R, Oates RD, van der Poel S, St John B, Sigman M, Sokol R, Tournaye H

Abstract
BACKGROUND: Herein, we describe the consensus guideline methodology, summarize the evidence-based recommendations we provided to the World Health Organization (WHO) for their consideration in the development of global guidance and present a narrative review of the diagnosis of male infertility as related to the eight prioritized (problem or population (P), intervention (I), comparison (C) and outcome(s) (O) (PICO)) questions. Additionally, we discuss the challenges and research gaps identified during the synthesis of this evidence.
OBJECTIVE AND RATIONALE: The aim of this paper is to present an evidence-based approach for the diagnosis of male infertility as related to the eight prioritized PICO questions.
SEARCH METHODS: Collating the evidence to support providing recommendations involved a collaborative process as developed by WHO, namely: identification of priority questions and critical outcomes; retrieval of up-to-date evidence and existing guidelines; assessment and synthesis of the evidence; and the formulation of draft recommendations to be used for reaching consensus with a wide range of global stakeholders. For each draft recommendation the quality of the supporting evidence was then graded and assessed for consideration during a WHO consensus.
OUTCOMES: Evidence was synthesized and recommendations were drafted to address the diagnosis of male infertility specifically encompassing the following: What is the prevalence of male infertility and what proportion of infertility is attributable to the male? Is it necessary for all infertile men to undergo a thorough evaluation? What is the clinical (ART/non ART) value of traditional semen parameters? What key male lifestyle factors impact on fertility (focusing on obesity, heat and tobacco smoking)? Do supplementary oral antioxidants or herbal therapies significantly influence fertility outcomes for infertile men? What are the evidence-based criteria for genetic screening of infertile men? How does a history of neoplasia and related treatments in the male impact on (his and his partner's) reproductive health and fertility options? And lastly, what is the impact of varicocele on male fertility and does correction of varicocele improve semen parameters and/or fertility?
WIDER IMPLICATIONS: This evidence synthesis analysis has been conducted in a manner to be considered for global applicability for the diagnosis of male infertility.

PMID: 28981651 [PubMed - as supplied by publisher]

Categories: Literature Watch

A Cell-Free Biosensor for Detecting Quorum Sensing Molecules in P. aeruginosa-Infected Respiratory Samples.

Fri, 2017-10-06 07:42

A Cell-Free Biosensor for Detecting Quorum Sensing Molecules in P. aeruginosa-Infected Respiratory Samples.

ACS Synth Biol. 2017 Oct 05;:

Authors: Wen KY, Cameron L, Chappell J, Jensen K, Bell DJ, Kelwick R, Kopniczky M, Davies JC, Filloux A, Freemont PS

Abstract
Synthetic biology designed cell-free biosensors are a promising new tool for the detection of clinically relevant biomarkers in infectious diseases. Here, we report that a modular DNA-encoded biosensor in cell-free protein expression systems can be used to measure a bacterial biomarker of Pseudomonas aeruginosa infection from human sputum samples. By optimizing the cell-free system and sample extraction, we demonstrate that the quorum sensing molecule 3-oxo-C12-HSL in sputum samples from cystic fibrosis lungs can be quantitatively measured at nanomolar levels using our cell-free biosensor system, and is comparable to LC-MS measurements of the same samples. This study further illustrates the potential of modular cell-free biosensors as rapid, low-cost detection assays that can inform clinical practice.

PMID: 28981256 [PubMed - as supplied by publisher]

Categories: Literature Watch

Prenatal Maternal Stress and the Risk of Asthma in Children.

Fri, 2017-10-06 07:42

Prenatal Maternal Stress and the Risk of Asthma in Children.

Front Pediatr. 2017;5:202

Authors: Douros K, Moustaki M, Tsabouri S, Papadopoulou A, Papadopoulos M, Priftis KN

Abstract
Emerging evidence indicate that maternal prenatal stress (MPS) can result in a range of long-term adverse effects in the offspring. The underlying mechanism of MPS is not fully understood. However, its complexity is emphasized by the number of purportedly involved pathways namely, placental deregulated metabolism of maternal steroids, impaired maturation of fetal HPA axis, imbalanced efflux of commensal bacteria across the placenta, and skewed immune development toward Th2. Fetal programming probably exerts a pivotal role in the end result of the above pathways through the modulation of gene expression. In this review, we highlight the current knowledge from epidemiological and experimental studies regarding the effects of MPS on asthma development in the offspring.

PMID: 28979893 [PubMed]

Categories: Literature Watch

Guanylate cyclase 2C agonism corrects CFTR mutants.

Fri, 2017-10-06 07:42

Guanylate cyclase 2C agonism corrects CFTR mutants.

JCI Insight. 2017 Oct 05;2(19):

Authors: Arora K, Huang Y, Mun K, Yarlagadda S, Sundaram N, Kessler MM, Hannig G, Kurtz CB, Silos-Santiago I, Helmrath M, Palermo JJ, Clancy JP, Steinbrecher KA, Naren AP

Abstract
Cystic fibrosis (CF) is a genetic disorder in which epithelium-generated fluid flow from the lung, intestine, and pancreas is impaired due to mutations disrupting CF transmembrane conductance regulator (CFTR) channel function. CF manifestations of the pancreas and lung are present in the vast majority of CF patients, and 15% of CF infants are born with obstructed gut or meconium ileus. However, constipation is a significantly underreported outcome of CF disease, affecting 47% of the CF patients, and management becomes critical in the wake of increasing life span of CF patients. In this study, we unraveled a potentially novel molecular role of a membrane-bound cyclic guanosine monophosphate-synthesizing (cGMP-synthesizing) intestinal enzyme, guanylate cyclase 2C (GCC) that could be targeted to ameliorate CF-associated intestinal fluid deficit. We demonstrated that GCC agonism results in functional rescue of murine F508del/F508del and R117H/R117H Cftr and CFTR mutants in CF patient-derived intestinal spheres. GCC coexpression and activation facilitated processing and ER exit of F508del CFTR and presented a potentially novel rescue modality in the intestine, similar to the CF corrector VX-809. Our findings identify GCC as a biological CFTR corrector and potentiator in the intestine.

PMID: 28978796 [PubMed - as supplied by publisher]

Categories: Literature Watch

Cigarette smoke activates CFTR through ROS-stimulated cAMP signaling in human bronchial epithelial cells.

Fri, 2017-10-06 07:42

Cigarette smoke activates CFTR through ROS-stimulated cAMP signaling in human bronchial epithelial cells.

Am J Physiol Cell Physiol. 2017 Oct 04;:ajpcell.00099.2017

Authors: Wong FH, AbuArish A, Matthes E, Turner MJ, Greene LE, Cloutier A, Robert R, Thomas DY, Cosa G, Cantin AM, Hanrahan JW

Abstract
Air pollution stimulates airway epithelial secretion through a cholinergic reflex that is unaffected in cystic fibrosis (CF), yet a strong correlation is observed between passive smoke exposure in the home and impaired lung function in CF children. Our aim was to study the effects of low smoke concentrations on CFTR function in vitro. Cigarette smoke extract stimulated robust anion secretion that was transient, mediated by cystic fibrosis transmembrane conductance regulator (CFTR), and dependent on cAMP-dependent protein kinase activation. Secretion was initiated by reactive oxygen species (ROS) and mediated by at least two distinct pathways; autocrine activation of EP4 prostanoid receptors, and stimulation of Ca2+ store-operated cAMP signaling. The response was absent in cells expressing the most common disease-causing mutant F508del-CFTR. In addition to the initial secretion, prolonged exposure of non-CF bronchial epithelial cells to low levels of smoke also caused a gradual decline in CFTR functional expression. F508del-CFTR channels that had been rescued by the CF drug combination VX-809 (lumacaftor) + VX-770 (ivacaftor) were more sensitive to this downregulation than wild-type CFTR. The results suggest that CFTR-mediated secretion during acute cigarette smoke exposure initially protects the airway epithelium while prolonged exposure reduces CFTR functional expression and reduces the efficacy of CF drugs.

PMID: 28978522 [PubMed - as supplied by publisher]

Categories: Literature Watch

Ototoxicity monitoring through the eyes of the treating physician: Perspectives from pulmonology and medical oncology.

Fri, 2017-10-06 07:42

Ototoxicity monitoring through the eyes of the treating physician: Perspectives from pulmonology and medical oncology.

Int J Audiol. 2017 Oct 05;:1-6

Authors: Garinis AC, Cornell A, Allada G, Fennelly KP, Maggiore RJ, Konrad-Martin D

Abstract
OBJECTIVES: Integrating audiological management into the care pathways of clinical specialties that prescribe ototoxic medications for essential, often life-preserving medical care that is critical for early hearing loss identification and remediation. Research shows that successful implementation of a new health service or intervention requires alignment of goals among provider groups, institutional leadership and patients. Thoughtful consideration of the physician's viewpoints about ototoxicity and its implications for treatment planning is, therefore, important for the implementation and enduring success of an ototoxicity monitoring programme (OMP).
DESIGN: This discussion paper uses qualitative methods to explore the perspectives of four physicians on OMP provision in their patient populations.
STUDY SAMPLE: Three pulmonologists and one oncologist completed the written survey or survey-based interview described in this report.
RESULTS: Each physician indicated that (i) ototoxicity is a potential problem for their patients; (ii) monitoring hearing is important to ensure good quality of life among their patients and (iii) treatment modification would be considered if an alternative treatment option were available. The physicians differed in their approaches to ototoxicity monitoring, from routine referrals to audiology, to relying on patient self-referral.
CONCLUSION: Physician provider input is needed to optimise monitoring schedules and OMP care coordination with audiology.

PMID: 28978238 [PubMed - as supplied by publisher]

Categories: Literature Watch

Upregulation of CFTR in patients with endometriosis and its involvement in NFκB-uPAR dependent cell migration.

Fri, 2017-10-06 07:42
Related Articles

Upregulation of CFTR in patients with endometriosis and its involvement in NFκB-uPAR dependent cell migration.

Oncotarget. 2017 Sep 15;8(40):66951-66959

Authors: Huang W, Jin A, Zhang J, Wang C, Tsang LL, Cai Z, Zhou X, Chen H, Chan HC

Abstract
Endometriotic tissues exhibit high migration ability with the underlying mechanisms remain elusive. Our previous studies have demonstrated that cystic fibrosis transmembrane conductance regulator (CFTR) acts as a tumor suppressor regulating cell migration. In the present study, we explored whether CFTR plays a role in the development of human endometriosis. We found that both mRNA and protein expression levels of CFTR and urokinase-type plasminogen activator receptor (uPAR) were significantly increased in ectopic endometrial tissues from patients with endometriosis compared to normal endometrial tissues from women without endometriosis and positively correlated. In human endometrial Ishikawa (ISK) cells, overexpression of CFTR stimulated cell migration with upregulated NFκB p65 and uPAR. Knockdown of CFTR inhibited cell migration. Furthermore, inhibition of NFκB with its inhibitors (curcumin or Bay) significantly reduced the expression of uPAR and cell migration in the CFTR-overexpressing ISK cells. Collectively, the present results suggest that the CFTR-NFκB-uPAR signaling may contribute to the progression of human endometriosis, and indicate potential targets for diagnosis and treatment.

PMID: 28978008 [PubMed]

Categories: Literature Watch

CFTR: Ferreting Out Its Role in Cystic Fibrosis-Related Diabetes.

Thu, 2017-10-05 07:12

CFTR: Ferreting Out Its Role in Cystic Fibrosis-Related Diabetes.

Endocrinology. 2017 Oct 01;158(10):3319-3321

Authors: Satin LS, Parekh VS

PMID: 28977616 [PubMed - in process]

Categories: Literature Watch

Glucose-Sensitive CFTR Suppresses Glucagon Secretion by Potentiating KATP Channels in Pancreatic Islet α Cells.

Thu, 2017-10-05 07:12

Glucose-Sensitive CFTR Suppresses Glucagon Secretion by Potentiating KATP Channels in Pancreatic Islet α Cells.

Endocrinology. 2017 Oct 01;158(10):3188-3199

Authors: Huang WQ, Guo JH, Zhang XH, Yu MK, Chung YW, Ruan YC, Chan HC

Abstract
The secretion of glucagon by islet α cells is normally suppressed by high blood glucose, but this suppressibility is impaired in patients with diabetes or cystic fibrosis (CF), a disease caused by mutations in the gene encoding CF transmembrane conductance regulator (CFTR), a cyclic adenosine monophosphate-activated Cl- channel. However, precisely how glucose regulates glucagon release remains controversial. Here we report that elevated glucagon secretion, together with increased glucose-induced membrane depolarization and Ca2+ response, is found in CFTR mutant (DF508) mice/islets compared with the wild-type. Overexpression of CFTR in AlphaTC1-9 cells results in membrane hyperpolarization and reduced glucagon release, which can be reversed by CFTR inhibition. CFTR is found to potentiate the adenosine triphosphate-sensitive K+ (KATP) channel because membrane depolarization and whole-cell currents sensitive to KATP blockers are significantly greater in wild-type/CFTR-overexpressed α cells compared with that in DF508/non-overexpressed cells. KATP knockdown also reverses the suppressive effect of CFTR overexpression on glucagon secretion. The results reveal that by potentiating KATP channels, CFTR acts as a glucose-sensing negative regulator of glucagon secretion in α cells, a defect of which may contribute to glucose intolerance in CF and other types of diabetes.

PMID: 28977595 [PubMed - in process]

Categories: Literature Watch

CFTR Influences Beta Cell Function and Insulin Secretion Through Non-Cell Autonomous Exocrine-Derived Factors.

Thu, 2017-10-05 07:12

CFTR Influences Beta Cell Function and Insulin Secretion Through Non-Cell Autonomous Exocrine-Derived Factors.

Endocrinology. 2017 Oct 01;158(10):3325-3338

Authors: Sun X, Yi Y, Xie W, Liang B, Winter MC, He N, Liu X, Luo M, Yang Y, Ode KL, Uc A, Norris AW, Engelhardt JF

Abstract
Although β-cell dysfunction in cystic fibrosis (CF) leads to diabetes, the mechanism by which the cystic fibrosis transmembrane conductance regulator (CFTR) channel influences islet insulin secretion remains debated. We investigated the CFTR-dependent islet-autonomous mechanisms affecting insulin secretion by using islets isolated from CFTR knockout ferrets. Total insulin content was lower in CF as compared with wild-type (WT) islets. Furthermore, glucose-stimulated insulin secretion (GSIS) was impaired in perifused neonatal CF islets, with reduced first, second, and amplifying phase secretion. Interestingly, CF islets compensated for reduced insulin content under static low-glucose conditions by secreting a larger fraction of islet insulin than WT islets, probably because of elevated SLC2A1 transcripts, increased basal inhibition of adenosine triphosphate-sensitive potassium channels (K-ATP), and elevated basal intracellular Ca2+. Interleukin (IL)-6 secretion by CF islets was higher relative to WT, and IL-6 treatment of WT ferret islets produced a CF-like phenotype with reduced islet insulin content and elevated percentage insulin secretion in low glucose. CF islets exhibited altered expression of INS, CELA3B, and several β-cell maturation and proliferation genes. Pharmacologic inhibition of CFTR reduced GSIS by WT ferret and human islets but similarly reduced insulin secretion and intracellular Ca2+ in CFTR knockout ferret islets, indicating that the mechanism of action is not through CFTR. Single-molecule fluorescent in situ hybridization, on isolated ferret and human islets and ferret pancreas, demonstrated that CFTR RNA colocalized within KRT7+ ductal cells but not endocrine cells. These results suggest that CFTR affects β-cell function via a paracrine mechanism involving proinflammatory factors secreted from islet-associated exocrine-derived cell types.

PMID: 28977592 [PubMed - in process]

Categories: Literature Watch

TESTS TO ASSESS SENSITIZATION TO ASPERGILLUS FUMIGATUS IN CYSTIC FIBROSIS.

Thu, 2017-10-05 07:12

TESTS TO ASSESS SENSITIZATION TO ASPERGILLUS FUMIGATUS IN CYSTIC FIBROSIS.

Rev Paul Pediatr. 2017 Jul-Sep;35(3):252-257

Authors: Aguiar SS, Damaceno N, Forte WCN

Abstract
OBJECTIVE: To evaluate the results of the tests used to identify the IgE mediated sensitization to Aspergillus fumigatus in patients with cystic fibrosis.
METHODS: This is a cross-sectional descriptive study with a convenience sample of 86 patients diagnosed with cystic fibrosis in the Reference Service in Cystic Fibrosis at a tertiary teaching hospital. The following tests were performed to assess the sensitization to A. fumigatus in patients with cystic fibrosis: Total serum IgE, eosinophil count, fungus detection through oropharyngeal swab or sputum culture, serum-specific IgE, and immediate-type hypersensitivity (IgE) skin tests. We compared the results of the different tests performed.
RESULTS: In 33 (38.4%) patients with cystic fibrosis, with ages ranging from 1 to 33 years (median of 8 years), the IgE-mediated A. fumigatus sensitization test results were: in 16 patients, there was an increase in serum-specific IgE (>0.35 kU/L); in 23, skin tests were positive; and six had sensitization in both tests. We observed two patients with eosinophilia (>1,000 eosinophils/mm3) and seven with increasing total serum IgE (>1,000 IU/mL), all of whom obtained negative results in skin tests and had no IgE increase specific to A. fumigatus. A. fumigatus was not detected in oropharyngeal swabs and/or sputum culture of any patients.
CONCLUSIONS: We conclude that, among the tests used to assess sensitization to A. fumigatus in cystic fibrosis patients, both serum-specific IgE and immediate-type hypersensitivity (IgE) skin tests are required. Serum eosinophilia and respiratory secretion culture were not essential in this study.

PMID: 28977288 [PubMed - in process]

Categories: Literature Watch

Targeting the alternative sigma factor RpoN to combat virulence in Pseudomonas aeruginosa.

Thu, 2017-10-05 07:12

Targeting the alternative sigma factor RpoN to combat virulence in Pseudomonas aeruginosa.

Sci Rep. 2017 Oct 03;7(1):12615

Authors: Lloyd MG, Lundgren BR, Hall CW, Gagnon LB, Mah TF, Moffat JF, Nomura CT

Abstract
Pseudomonas aeruginosa is a Gram-negative, opportunistic pathogen that infects immunocompromised and cystic fibrosis patients. Treatment is difficult due to antibiotic resistance, and new antimicrobials are needed to treat infections. The alternative sigma factor 54 (σ(54), RpoN), regulates many virulence-associated genes. Thus, we evaluated inhibition of virulence in P. aeruginosa by a designed peptide (RpoN molecular roadblock, RpoN*) which binds specifically to RpoN consensus promoters. We expected that RpoN* binding to its consensus promoter sites would repress gene expression and thus virulence by blocking RpoN and/or other transcription factors. RpoN* reduced transcription of approximately 700 genes as determined by microarray analysis, including genes related to virulence. RpoN* expression significantly reduced motility, protease secretion, pyocyanin and pyoverdine production, rhamnolipid production, and biofilm formation. Given the effectiveness of RpoN* in vitro, we explored its effects in a Caenorhabditis elegans-P. aeruginosa infection model. Expression of RpoN* protected C. elegans in a paralytic killing assay, whereas worms succumbed to paralysis and death in its absence. In a slow killing assay, which mimics establishment and proliferation of an infection, C. elegans survival was prolonged when RpoN* was expressed. Thus, blocking RpoN consensus promoter sites is an effective strategy for abrogation of P. aeruginosa virulence.

PMID: 28974743 [PubMed - in process]

Categories: Literature Watch

Scedosporium boydii CatA1 and SODC recombinant proteins, new tools for serodiagnosis of Scedosporium infection of patients with cystic fibrosis.

Thu, 2017-10-05 07:12

Scedosporium boydii CatA1 and SODC recombinant proteins, new tools for serodiagnosis of Scedosporium infection of patients with cystic fibrosis.

Diagn Microbiol Infect Dis. 2017 Aug 26;:

Authors: Mina S, Staerck C, Marot A, Godon C, Calenda A, Bouchara JP, Fleury MJJ

Abstract
Scedosporium species rank the second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF), after Aspergillus fumigatus. In CF, these fungi may cause various respiratory infections similar to those caused by A. fumigatus, including bronchitis and allergic broncho-pulmonary mycoses. Diagnosis of these infections relies on the detection of serum antibodies using crude antigenic extracts. However, many components of these extracts are common to Scedosporium and Aspergillus species, leading to cross-reactions. Here, 5 recombinant proteins from S. apiospermum or S. boydii were produced, and their value in serodiagnosis of Scedosporium infections was investigated by enzyme-linked immunosorbent assay. Two of them, corresponding to the Scedosporium catalase A1 or cytosolic Cu,Zn-superoxyde dismutase, allowed the detection of Scedosporium infection, and the differentiation with an Aspergillus infection. These recombinant proteins therefore may serve as a basis for the development of a standardized serological test.

PMID: 28974395 [PubMed - as supplied by publisher]

Categories: Literature Watch

Towards individualized diagnostics of biofilm-associated infections: a case study.

Wed, 2017-10-04 09:49

Towards individualized diagnostics of biofilm-associated infections: a case study.

NPJ Biofilms Microbiomes. 2017;3:22

Authors: Müsken M, Klimmek K, Sauer-Heilborn A, Donnert M, Sedlacek L, Suerbaum S, Häussler S

Abstract
Organized within biofilm communities, bacteria exhibit resistance towards a broad spectrum of antibiotics. Thus, one might argue that bacteria isolated from biofilm-associated chronic infections should be subjected to resistance profiling under biofilm growth conditions. Various test systems have been developed to determine the biofilm-associated resistance; however, it is not clear to what extent the in vitro results reflect the situation in vivo, and whether the biofilm-resistance profile should guide clinicians in their treatment choice. To address this issue, we used confocal microscopy in combination with live/dead staining, and profiled biofilm-associated resistance of a large number (>130) of clinical Pseudomonas aeruginosa isolates from overall 15 cystic fibrosis patients. Our results demonstrate that in addition to a general non-responsiveness of bacteria when grown under biofilm conditions, there is an isolate-specific and antibiotic-specific biofilm-resistance profile. This individual resistance profile is independent on the structural properties of the biofilms. Furthermore, biofilm resistance is not linked to the resistance profile under planktonic growth conditions, or a mucoid, or small colony morphology of the tested isolates. Instead, it seems that individual biofilm structures evolve during biofilm-associated growth and are shaped by environment-specific cues. In conclusion, our results demonstrate that biofilm resistance profiles are isolate specific and cannot be deduced from commonly studied phenotypes. Further clinical studies will have to show the added value of biofilm-resistance profiling. Individualized diagnosis of biofilm resistance might lead to more rational recommendations for antimicrobial therapy and, thus, increased effectiveness of the treatment of chronically infected patients.

PMID: 28970943 [PubMed]

Categories: Literature Watch

Evaluation of obstructive sleep apnea in non-cystic fibrosis bronchiectasis: A cross-sectional study.

Wed, 2017-10-04 06:47

Evaluation of obstructive sleep apnea in non-cystic fibrosis bronchiectasis: A cross-sectional study.

PLoS One. 2017;12(10):e0185413

Authors: Faria Júnior NS, Urbano JJ, Santos IR, Silva AS, Perez EA, Souza ÂH, Nascimento OA, Jardim JR, Insalaco G, Oliveira LVF, Stirbulov R

Abstract
The relationship between sleep disorders and bronchiectasis has not been well described. We hypothesize that, due to the irreversible dilatation of the bronchi, the presence of secretions, and airflow obstruction, patients with non-cystic fibrosis bronchiectasis may be predisposed to hypoxemia during sleep, or to symptoms that may lead to arousal. A cross-sectional observational study was performed involving 49 patients with a clinical diagnosis of non-cystic fibrosis bronchiectasis (NCFB). All patients underwent clinical evaluation, spirometry, and polysomnography, and were evaluated for the presence of excessive daytime sleepiness (EDS) and risk of obstructive sleep apnea (OSA). The mean age of the participants was 50.3 ± 13.6 years; 51.1% of patients were male and had a mean body mass index of 23.8 ± 3.4 kg/m2. The mean total sleep time (TST) was 325.15 ± 64.22 min with a slight reduction in sleep efficiency (84.01 ± 29.2%). Regarding sleep stages, stage 1 sleep and REM sleep were abnormal. OSA was present in 40.82% of the patients. The mean arousal index was 5.6 ± 2.9/h and snoring was observed in 71.43% of the patients. The oxygen desaturation index (ODI) was 14.35 ± 15.36/h, mean minimum oxygen saturation (SpO2 nadir) was 83.29 ± 7.99%, and mean TST with an SpO2 less than 90% was 30.21 ± 60.48 min. EDS was exhibited by 53.06% of the patients and 55.1% were at high risk of developing OSA. The patients infected by Pseudomonas aeruginosa had higher apnea-hypopnea indices, ODI, and TST with SpO2 < 90%, and lower values of SpO2 nadir. Adult patients with clinically stable NCFB, especially those infected by Pseudomonas aeruginosa, display EDS and a high prevalence of OSA, associated with considerable oxygen desaturation during sleep.

PMID: 28972989 [PubMed - in process]

Categories: Literature Watch

Exploring approaches to facilitate family communication of genetic risk information after cystic fibrosis population carrier screening.

Wed, 2017-10-04 06:47

Exploring approaches to facilitate family communication of genetic risk information after cystic fibrosis population carrier screening.

J Community Genet. 2017 Oct 02;:

Authors: Gorrie A, Archibald AD, Ioannou L, Curnow L, McClaren B

Abstract
Population carrier screening for cystic fibrosis (CF) enables individuals with no known family history of the condition to ascertain their risk of having a child with CF. When an individual is identified as a carrier of CF, a life-shortening condition, they are encouraged to inform their relatives who are at increased risk of being a carrier. Research suggests that the uptake of CF carrier testing amongst relatives of carriers or people with CF is low. This study aimed to explore approaches to facilitate the process of family communication of genetic information after an individual is identified as a carrier of CF through population screening. Five key informants were interviewed to inform the development of a telephone survey which was administered to 21 individuals identified as carriers of CF through population carrier screening at Victorian Clinical Genetics Services. This study suggests that providing carriers with additional information and follow-up support would be appreciated by carriers and could result in more accurate information being disseminated more widely within families, which could lead to more at-risk relatives accessing testing. Suggested strategies to enhance current practice include mailing a fact sheet to carriers and a follow-up telephone call provided by a genetic counsellor to carriers to offer further support in communicating this information to their relatives.

PMID: 28971321 [PubMed - as supplied by publisher]

Categories: Literature Watch

The proteome speciation of an immortalized cystic fibrosis cell line: New perspectives on the pathophysiology of the disease.

Wed, 2017-10-04 06:47

The proteome speciation of an immortalized cystic fibrosis cell line: New perspectives on the pathophysiology of the disease.

J Proteomics. 2017 Sep 29;:

Authors: Michele P, Claudia L, Assunta G, Loretta B, Alessandro A, Jlenia B, Alessandro P, Laura B, Luca B

Abstract
Cystic Fibrosis (CF) is a recessively inherited disease caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. CFTR has a pivotal role in the onset of CF, and several proteins are involved in its homeostasis. To study CFTR interactors at protein species level, we used a functional proteomics approach combining 2D-DIGE, mass spectrometry and enrichment analysis. A human bronchial epithelial cell line with cystic fibrosis (CFBE41o-) and the control (16HBE14o-) were used for the comparison. 73 differentially abundant spots were identified and some validated by western-blot. Enrichment analysis highlighted molecular pathways in which ezrin, HSP70, endoplasmin and lamin A/C, in addition to CFTR, were considered central hubs in CFTR homeostasis. These proteins acquire different functions through post-translational modifications, emphasizing the importance of studying the CF proteome at protein species level. Moreover, serpin H1, prelamin A/C, protein-SET and cystatin-B were associated to CF, demonstrating the importance of heat shock response, cross-talk between the cytoskeleton and signal transduction, chronic inflammation and alteration of CFTR gating in the pathophysiology of the disease. These results open new perspectives for the understanding of the proteostasis network, characteristic of CF pathology, and could provide a springboard for new therapeutic strategies.
BIOLOGICAL SIGNIFICANCE: Homeostasis of CFTR is a dynamic process managed by multiple proteostatic pathways. The used gel-based proteomic approach and enrichment analysis pointed out protein species variations among Human Bronchial (16HBE14o-) and Cystic Fibrosis Bronchial Epithelial cell lines (CFBE41o-) and specific molecular mechanisms involved in CF. In particular, we have highlighted HSP70 (HSP7C), HSP90 (endoplasmin), ERM proteins (ezrin), and lamin-A/C as central hubs of the functional analysis. Moreover, for the first time we consider serpin H1, lamin A/C, protein-SET and cystatin-B important player in CF, affecting acute exacerbation, cytoskeleton reorganization, CFTR gating and chronic inflammation in CF. Due to the presence of different spots corresponding to the same protein, we focalize our attention on the idea that a "protein species discourse" is mandatory to well-define functional roles of proteins. Our approach has permitted to pay attention to the molecular mechanisms which regulate pathways directly or indirectly involved with CFTR defects: heat shock response, cross-talk between cytoskeleton and signal transduction, chronic inflammation and alteration of CFTR gating. Our data could open new perspectives into the understanding of CF, identifying potential targets for drug treatments in order to alleviate Δ508CFTR membrane instability and consequently increase life expectancy for CF patients.

PMID: 28970102 [PubMed - as supplied by publisher]

Categories: Literature Watch

Group B streptococcus (GBS) is an important pathogen in human disease- but what about in cystic fibrosis?

Wed, 2017-10-04 06:47

Group B streptococcus (GBS) is an important pathogen in human disease- but what about in cystic fibrosis?

BMC Infect Dis. 2017 Oct 02;17(1):660

Authors: Skolnik K, Nguyen A, Thornton CS, Waddell B, Williamson T, Rabin HR, Parkins MD

Abstract
BACKGROUND: Group B Streptococcus (GBS) is a common commensal capable of causing severe invasive infections. Most GBS infections occur in neonates (often as pneumonia). GBS can also cause infection in adults with diabetes and other immunological impairments but rarely leads to pneumonia in adults. GBS has occasionally been found in the sputum of Cystic Fibrosis (CF) patients, an inherited condition known for progressive lung disease. However, the epidemiology and clinical significance of GBS in CF are not understood.
METHODS: We retrospectively reviewed a large single-centre adult CF population with an associated comprehensive, prospectively collected bacterial biobank beginning in 1978. We identified all individuals with GBS isolated from their sputum on at least one occasion. The primary outcome was risk of pulmonary exacerbation (PEx) at the time of the first GBS isolate compared to the preceding visit. Secondary outcomes included determining: prevalence of GBS infection in a CF population, whether GBS infections where transient or persistent, whether GBS strains were shared among patients, change in % predicted FEV1 at the time of GBS isolate compared to the preceding visit, PEx frequency after the first GBS isolate, change in % predicted FEV1 after the first GBS isolate, and complications of GBS infection.
RESULTS: GBS was uncommon, infecting 3.5% (11/318) adults within our cohort. Only three individuals developed persistent GBS infection, all lasting > 12 months. There were no shared GBS strains among patients. PEx risk was not increased at initial GBS isolation (RR 5.0, CI 0.69-36.1, p=0.10). In the two years preceding initial GBS isolation compared to the two following years, there was no difference in PEx frequency (median 2, range 0-4 vs 1, range 0 to 5, respectively, p=0.42) or lung function decline, as measured by % predicted FEV1, (median -1.0%, range -19 to 7% vs median -6.0%, range -18 to 22%, p=0.86). There were no invasive GBS infections.
CONCLUSION: In adults with CF, GBS is uncommon and is generally a transient colonizer of the lower airways. Despite the presence of structural lung disease and impaired innate immunity in CF, incident GBS infection did not increase PEx risk, PEx frequency, rate of lung function decline, or other adverse clinical outcomes.

PMID: 28969684 [PubMed - in process]

Categories: Literature Watch

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