Randomised, double-blind, placebo-controlled pilot trial of omeprazole in idiopathic pulmonary fibrosis

Background

Cough is a common, disabling symptom of idiopathic pulmonary fibrosis (IPF), which may be exacerbated by acid reflux. Inhibiting gastric acid secretion could potentially reduce cough. This study aimed to determine the feasibility of a larger, multicentre trial of omeprazole for cough in IPF, to assess safety and to quantify cough.

Methods

Single-centre, double-blind, randomised, placebo-controlled pilot trial of the proton pump inhibitor (PPI) omeprazole (20 mg twice daily for 3 months) in patients with IPF. Primary objectives were to assess feasibility and acceptability of trial procedures. The primary clinical outcome was cough frequency.

Results

Forty-five participants were randomised (23 to omeprazole, 22 to placebo), with 40 (20 in each group) having cough monitoring before and after treatment. 280 patients were screened to yield these numbers, with barriers to discontinuing antacids the single biggest reason for non-recruitment. Recruitment averaged 1.5 participants per month. Geometric mean cough frequency at the end of treatment, adjusted for baseline, was 39.1% lower (95% CI 66.0% lower to 9.3% higher) in the omeprazole group compared with placebo. Omeprazole was well tolerated and adverse event profiles were similar in both groups, although there was a small excess of lower respiratory tract infection and a small fall in forced expiratory volume and forced vital capacity associated with omeprazole.

Conclusions

A large randomised controlled trial of PPIs for cough in IPF appears feasible and justified but should address barriers to randomisation and incorporate safety assessments in relation to respiratory infection and changes in lung function.

The role of joint engagement in the development of language in a community-derived sample of slow-to-talk children

We explored whether supported (SJE) or coordinated joint engagement (CJE) between mothers recruited from the community and their 24-month-old children who were slow-to-talk at 18 months old were associated with child language scores at ages 24, 36, and 48 months (n = 197). We further explored whether SJE or CJE modified the concurrent positive associations between maternal responsive behaviours and language scores. Previous research has shown that SJE, maternal expansions, imitations, and responsive questions were associated with better language scores. Our main finding was that SJE but not CJE was consistently positively associated with 24- and 36-month-old expressive and receptive language scores, but not with 48-month-old language scores. SJE modified how expansions and imitations, but not responsive questions, were associated with language scores; the associations were evident in all but the highest levels of SJE. Further research is necessary to test these findings in other samples before clinical recommendations can be made.

Cough in Patients With Lung Cancer: A Longitudinal Observational Study of Characterization and Clinical Associations

BACKGROUND

Cough is common in patients with lung cancer, and current antitussive treatments are suboptimal. There are little published data describing cough in patients with lung cancer or work assessing clinical associations. The aim of this study is to fill that gap.

METHODS

This was a longitudinal prospective observational single-cohort study over 60 days. Patients were assessed through self-reported validated scales and, in a subsample, ambulatory cough monitoring at study entry (day 0), day 30, and day 60.

RESULTS

At study entry, 177 patients were included and 153 provided data at day 60. The median duration of cough was 52 weeks (interquartile range, 8.5-260). Cough was described as severe enough to warrant treatment in 62% of the patients. Depending on the scale used, performance status was associated with both cough severity and cough impact (P < .001) at study entry, whereas higher cough severity at study entry was associated with female sex (P = .02), asthma (P = .035), and reflux disease (P < .001). Cough impact at study entry was additionally associated with experiencing nausea (P = .018). Cancer characteristics (ie, cancer stage, histology) were not associated with cough severity nor cough impact; neither was smoking or COPD.

CONCLUSIONS

This is the first study to describe characteristics of cough in patients with lung cancer and to identify clinical associations that may be relevant for its treatment. Our data suggest that cough is a frequent and distressing symptom and an unmet clinical need. Its association with gastrointestinal symptoms in this study may improve our understanding of pathophysiology and therapeutic options for cough occurring in patients with lung cancer.

An ecological halo surrounding a large offshore artificial reef: Sediments, infauna, and fish foraging

Artificial reefs are deployed in coastal systems to meet a range of social objectives and infrastructure requirements, such as recreational diving and fisheries enhancement. Such reefs are typically deployed on soft sediments and yet we know little of their effect on the biophysical characteristics of the surrounding benthos. This study investigated the composition of benthic infauna, sediment characteristics, and demersal fish foraging activity surrounding a large, steel, designed offshore artificial reef (OAR), measuring 12 m × 16 m x 12 m (height x length x width) and weighing approximately 42 tonnes. Using a gradient approach we established four transects with sediment sampling sites located 15, 30, 60, 120 and 240 m from the OAR. Taxon richness of infauna was lower close to the OAR (15, 30 m), and abundances of total infauna elevated at 15 m, driven largely by two families of polychaete (Onuphidae and Spionidae). Sediment characteristics (grain size, total organic carbon, metals) did not vary with distance from the OAR. Using unbaited videos we established that fish foraging activity on the soft sediments was enhanced close to the OAR (15 m), with a 5-10 fold increase in total foraging time that was largely accounted for by the activity of four benthivorous fish species (blue morwong Nemadactylus douglasii, the silver trevally Pseudocaranx georgianus, and goatfishes Upeneichthys vlamingii and U. lineatus). Fish foraging may cause changes in the composition of benthic infauna due to disturbance and selective predation. The effective benthic 'ecological halo' or 'footprint' of the OAR was 15 times the area of the actual reef. We demonstrate that a single large OAR can influence the surrounding benthic invertebrate and vertebrate communities, but that the effects are highly localised.

Calibration of a high spectral resolution lidar using a Michelson interferometer, with data examples from ORACLES

The NASA Langley airborne second-generation High Spectral Resolution Lidar (HSRL-2) uses a density-tuned field-widened Michelson interferometer to implement the HSRL technique at 355 nm. The Michelson interferometer optically separates the received backscattered light between two channels, one of which is dominated by molecular backscattering, while the other contains most of the light backscattered by particles. This interferometer achieves high and stable contrast ratio, defined as the ratio of particulate backscatter signal received by the two channels. We show that a high and stable contrast ratio is critical for precise and accurate backscatter and extinction retrievals. Here, we present retrieval equations that take into account the incomplete separation of particulate and molecular backscatter in the measurement channels. We also show how the accuracy of the contrast ratio assessment propagates to error in the optical properties. For both backscattering and extinction, larger errors are produced by underestimates of the contrast ratio (compared to overestimates), more extreme aerosol loading, and-most critically-smaller true contrast ratios. We show example results from HSRL-2 aboard the NASA ER-2 aircraft from the 2016 ORACLES field campaign in the southeast Atlantic, off the coast of Africa, during the biomass burning season. We include a case study where smoke aerosol in two adjacent altitude layers showed opposite differences in extinction- and backscatter-related Ångström exponents and a reversal of the lidar ratio spectral dependence, signatures which are shown to be consistent with a relatively modest difference in smoke particle size.

Rotational Energy as Mass in H_{3}^{+} and Lower Limits on the Atomic Masses of D and ^{3}He

We have made precise measurements of the cyclotron frequency ratios H_{3}^{+}/HD^{+} and H_{3}^{+}/^{3}He^{+} and observe that different H_{3}^{+} ions result in different cyclotron frequency ratios. We interpret these differences as due to the molecular rotational energy of H_{3}^{+} changing its inertial mass. We also confirm that certain high J, K rotational levels of H_{3}^{+} have mean lifetimes exceeding several weeks. From measurements with the lightest H_{3}^{+} ion we obtain lower limits on the atomic masses of deuterium and helium-3 with respect to the proton.

Association of ORMDL3 with rhinovirus-induced endoplasmic reticulum stress and type I Interferon responses in human leucocytes

BACKGROUND

Children with risk alleles at the 17q21 genetic locus who wheeze during rhinovirus illnesses have a greatly increased likelihood of developing childhood asthma. In mice, overexpression of the 17q21 gene ORMDL3 leads to airway remodelling and hyperresponsiveness. However, the mechanisms by which ORMDL3 predisposes to asthma are unclear. Previous studies have suggested that ORMDL3 induces endoplasmic reticulum (ER) stress and production of the type I interferon (IFN)-regulated chemokine CXCL10.

OBJECTIVE

The purpose of this study was to determine the relationship between ORMDL3 and rhinovirus-induced ER stress and type I IFN in human leucocytes.

METHODS

ER stress was monitored by measuring HSPA5, CHOP and spliced XBP1 gene expression, and type I IFN by measuring IFNB1 (IFN-β) and CXCL10 expression in human cell lines and primary leucocytes following treatment with rhinovirus. Requirements for cell contact and specific cell type in ORMDL3 induction were examined by transwell assay and depletion experiments, respectively. Finally, the effects of 17q21 genotype on the expression of ORMDL3, IFNB1 and ER stress genes were assessed.

RESULTS

THP-1 monocytes overexpressing ORMDL3 responded to rhinovirus with increased IFNB1 and HSPA5. Rhinovirus-induced ORMDL3 expression in primary leucocytes required cell-cell contact, and induction was suppressed by plasmacytoid dendritic cell depletion. The degree of rhinovirus-induced ORMDL3, HSPA5 and IFNB1 expression varied by leucocyte type and 17q21 genotype, with the highest expression of these genes in the asthma-associated genotype.

CONCLUSIONS AND CLINICAL RELEVANCE

Multiple lines of evidence support an association between higher ORMDL3 and increased rhinovirus-induced HSPA5 and type I IFN gene expression. These associations with ORMDL3 are cell type specific, with the most significant 17q21 genotype effects on ORMDL3 expression and HSPA5 induction evident in B cells. Together, these findings have implications for how the interaction of increased ORMDL3 and rhinovirus may predispose to asthma.

Treatment Changes in Patients With Moderate to Severe Psoriasis: A Retrospective Chart Review

BACKGROUND

Psoriasis treatment involves topical medications, oral medications, phototherapy, and/or biologics. The treatments used depend on a myriad of factors that change over time.

OBJECTIVE

To characterise the frequency of and reasons for treatment changes in patients with moderate to severe psoriasis.

METHODS

A chart review examined treatment changes at 902 visits by 116 patients seen between January 1, 2010, and June 30, 2015, for moderate to severe psoriasis and the physicians' justifications for those changes. 'Treatment change' was defined as switching between, adding, or removing medication classes or switching within the oral or biologic class.

RESULTS

There were 221 visits with treatment changes identified, and a change occurred every 4.1 visits. On average, there were 1.2 treatment changes per year. Patients treated for at least 1 year averaged 1 treatment change every 16 months. The most common type of change was from one biologic to another biologic (24.9%), followed by adding a nonbiologic to a biologic (18.6%). The most common reason for switching was poor control or flare of psoriasis. Affordability was a more common problem for biologics than for nonbiologic treatments.

CONCLUSIONS

Biologic treatment options provide a major improvement over older systemic treatments, but patients still undergo frequent treatment changes to help control their disease.

Neurophenotypes in Airway Diseases. Insights from Translational Cough Studies

RATIONALE

Most airway diseases, including chronic obstructive pulmonary disease (COPD), are associated with excessive coughing. The extent to which this may be a consequence of increased activation of vagal afferents by pathology in the airways (e.g., inflammatory mediators, excessive mucus) or an altered neuronal phenotype is unknown. Understanding whether respiratory diseases are associated with dysfunction of airway sensory nerves has the potential to identify novel therapeutic targets.

OBJECTIVES

To assess the changes in cough responses to a range of inhaled irritants in COPD and model these in animals to investigate the underlying mechanisms.

METHODS

Cough responses to inhaled stimuli in patients with COPD, healthy smokers, refractory chronic cough, asthma, and healthy volunteers were assessed and compared with vagus/airway nerve and cough responses in a cigarette smoke (CS) exposure guinea pig model.

MEASUREMENTS AND MAIN RESULTS

Patients with COPD had heightened cough responses to capsaicin but reduced responses to prostaglandin E2 compared with healthy volunteers. Furthermore, the different patient groups all exhibited different patterns of modulation of cough responses. Consistent with these findings, capsaicin caused a greater number of coughs in CS-exposed guinea pigs than in control animals; similar increased responses were observed in ex vivo vagus nerve and neuron cell bodies in the vagal ganglia. However, responses to prostaglandin E2 were decreased by CS exposure.

CONCLUSIONS

CS exposure is capable of inducing responses consistent with phenotypic switching in airway sensory nerves comparable with the cough responses observed in patients with COPD. Moreover, the differing profiles of cough responses support the concept of disease-specific neurophenotypes in airway disease. Clinical trial registered with www.clinicaltrials.gov (NCT 01297790).

Addressing unmet needs in understanding asthma mechanisms: From the European Asthma Research and Innovation Partnership (EARIP) Work Package (WP)2 collaborators

Asthma is a heterogeneous, complex disease with clinical phenotypes that incorporate persistent symptoms and acute exacerbations. It affects many millions of Europeans throughout their education and working lives and puts a heavy cost on European productivity. There is a wide spectrum of disease severity and control. Therapeutic advances have been slow despite greater understanding of basic mechanisms and the lack of satisfactory preventative and disease modifying management for asthma constitutes a significant unmet clinical need. Preventing, treating and ultimately curing asthma requires co-ordinated research and innovation across Europe. The European Asthma Research and Innovation Partnership (EARIP) is an FP7-funded programme which has taken a co-ordinated and integrated approach to analysing the future of asthma research and development. This report aims to identify the mechanistic areas in which investment is required to bring about significant improvements in asthma outcomes.

Symptomatic Treatment of Cough Among Adult Patients With Lung Cancer: CHEST Guideline and Expert Panel Report

BACKGROUND

Cough among patients with lung cancer is a common but often undertreated symptom. We used a 2015 Cochrane systematic review, among other sources of evidence, to update the recommendations and suggestions of the American College of Chest Physicians (CHEST) 2006 guideline on this topic.

METHODS

The CHEST methodologic guidelines and the Grading of Recommendations, Assessment, Development, and Evaluation framework were used. The Expert Cough Panel based their recommendations on data from the Cochrane systematic review on the topic, uncontrolled studies, case studies, and the clinical context. Final grading was reached by consensus according to the Delphi method.

RESULTS

The Cochrane systematic review identified 17 trials of primarily low-quality evidence. Such evidence was related to both nonpharmacologic (cough suppression) and pharmacologic (demulcents, opioids, peripherally acting antitussives, or local anesthetics) treatments, as well as endobronchial brachytherapy.

CONCLUSIONS

Compared with the 2006 CHEST Cough Guideline, the current recommendations and suggestions are more specific and follow a step-up approach to the management of cough among patients with lung cancer, acknowledging the low-quality evidence in the field and the urgent need to develop more effective, evidence-based interventions through high-quality research.

Effect of aclidinium bromide on cough and sputum symptoms in moderate-to-severe COPD in three phase III trials

BACKGROUND

Cough and sputum are troublesome symptoms in chronic obstructive pulmonary disease (COPD) and are associated with adverse outcomes. The efficacy of aclidinium bromide 400 µg twice daily in patients with stable COPD has been established in two phase III studies (ACCORD COPD I and ATTAIN) and a phase IIIb active-comparator study. This analysis evaluated cough-related symptoms across these studies.

METHOD

Patients were randomised to placebo, aclidinium 200 µg or 400 µg twice daily in ACCORD (12 weeks) and ATTAIN (24 weeks), or to placebo, aclidinium 400 µg twice daily or tiotropium 18 µg once daily (6-week active-comparator study). Analysed end points included changes from baseline in Evaluating Respiratory Symptoms (E-RS; formerly known as EXAcerbations of Chronic pulmonary disease Tool), total and cough/sputum scores and frequency/severity of morning and night-time cough and sputum symptoms.

RESULTS

Data for 1792 patients were evaluated. E-RS cough/sputum domain scores were significantly reduced with aclidinium 400 µg versus placebo in ATTAIN (-0.7 vs -0.3, respectively; p<0.01) and the active-comparator study (-0.6 vs -0.2, respectively; p<0.01). In the active-comparator study, significantly greater improvements were observed with aclidinium versus placebo for severity of morning cough (-0.19 vs -0.02; p<0.01) and phlegm (-0.19 vs -0.02; p<0.05). In ACCORD, aclidinium reduced night-time cough frequency (-0.36 vs 0.1 for placebo; p<0.001) and severity (-0.24 vs -0.1 for placebo; p<0.05), and frequency of night-time sputum production (-0.37 vs 0.05 for placebo; p<0.001).

CONCLUSIONS

Aclidinium 400 µg twice daily improves cough and sputum expectoration versus placebo in stable COPD.

TRIAL REGISTRATION NUMBERS

NCT00891462; NCT01001494; NCT01462929.

Building a sustainable clinical academic workforce to meet the future healthcare needs of Australia and New Zealand: report from the first summit meeting

The delivery of healthcare that meets the requirements for quality, safety and cost-effectiveness relies on a well-trained medical workforce, including clinical academics whose career includes a specific commitment to research, education and/or leadership. In 2011, the Medical Deans of Australia and New Zealand published a review on the clinical academic workforce and recommended the development of an integrated training pathway for clinical academics. A bi-national Summit on Clinical Academic Training was recently convened to bring together all relevant stakeholders to determine how best to do this. An important part understood the lessons learnt from the UK experience after 10 years since the introduction of an integrated training pathway. The outcome of the summit was to endorse strongly the recommendations of the medical deans. A steering committee has been established to identify further stakeholders, solicit more information from stakeholder organisations, convene a follow-up summit meeting in late 2015, recruit pilot host institutions and engage the government and future funders.

A comparison of a forced-air warming system to traditional thermal support for rodent microenvironments

Thermal homeostasis is important for the well-being of laboratory rodents during experimental investigations involving chemical restraint. Anaesthesia-induced hypothermia may alter physiological processes, prolong recovery times, or result in death. Therefore, active warming may be needed to prevent excess heat loss from the rodent to the environment. Three methods of active warming were evaluated in typical rodent procedural areas and recovery cages: a forced-air warming system, infra-red heat emitter and circulating-water blanket. The first experiment involved recording the temperature of the immediate environment of the three devices, with and/or without the accompanying plastic drape, to simulate a surgical situation. In the second experiment, temperatures were recorded within cages that simulated a recovery situation with the same modalities. Forced-air warmer blankets (FAWB) were either wrapped around or placed underneath standard polycarbonate rodent cages and the results were compared with cage temperatures warmed by the heat emitter and circulating-water blanket. Temperatures were recorded at 0, 20, 40, and 60 min for each warming treatment, to determine mean temperature (± SEM) and the magnitude of increase (± SEM) between 0 and 60 min. All three devices showed an increase in temperature, but the FAWB with a plastic drape heated the procedural area microenvironment (Experiment 1) quickly and to a final temperature of 38.6°C (101.5°F) at 60 min, compared with 25°C (77°F) for the heat emitter and 28°C (82.4°F) for the circulating-water blanket. The magnitude of increase was significantly different for each treatment, but the FAWB with a plastic drape climbed 16.3°C (29.3°F) in 60 min. In Experiment 2, the FAWB wrapped around a cage, covered with a plastic drape, heated recovery cages to 32.5°C (90.5°F) compared to the heat emitter 26.4°C (79.5°F) and circulating-water blanket with drape 26.3°C (79.3°F). The magnitude of increase in the microenvironmental temperature was significantly higher for the FAWB, with the plastic drape wrapped around the recovery cage, compared to the other treatments. In both experiments, forced-air warming proved superior to the more traditional thermal support treatments in heating the microenvironments quickly and to an optimum ambient temperature. Forced-air warming devices should be considered when thermal support is required for rodent procedural areas and recovery cages.

Inhibition of Human Cytomegalovirus DNA Replication with a Phosphorothioate Cholesteryl-Modified Oligonucleotide is Mediated by Rapid Cellular Association and Virus-Facilitated Nuclear Localization

We have previously shown that an antisense phosphorothioate (PS) oligodeoxynucleotide has potent anti-human cytomegalovirus (HCMV) activity (GS Pari, AK Field & JA Smith, Antimicrobial Agents and Chemotherapy 1995, 39: 1157–1161). We have now used a modified PS oligonucleotide having three 2′-O-methyl nucleotides at the 3′ end and four 2′-O-methyl nucleotides at the 5′ end, containing a cholesteryl moiety linked to the 3′ end by a novel thiono-triester linkage. This compound, UL36ANTI-M, is superior to the PS (UL36ANTI) version with respect to antiviral potency, melting temperature and nuclease resistance. Also, we show that cellular association for this oligonucleotide is rapid, occurring within 15 min after treatment and is about 12-fold higher when compared to UL36ANTI. This increased rate of cellular association also correlates with antiviral properties in that a 15 min incubation with UL36ANTI-M was sufficient to achieve 75% inhibition of viral DNA replication and complete inhibition was achieved after only a 1 h pretreatment. In addition confocal microscopic examination showed a change in subcellular distribution from perinuclear to nuclear for oligonucleotides in HCMV-infected human fibroblasts. However, the total amount of cell-associated oligonucleotide was unchanged in infected cells.

Objective Cough Frequency, Airway Inflammation, and Disease Control in Asthma

BACKGROUND

Cough is recognized as an important troublesome symptom in the diagnosis and monitoring of asthma. Asthma control is thought to be determined by the degree of airway inflammation and hyperresponsiveness but how these factors relate to cough frequency is unclear. The goal of this study was to investigate the relationships between objective cough frequency, disease control, airflow obstruction, and airway inflammation in asthma.

METHODS

Participants with asthma underwent 24-h ambulatory cough monitoring and assessment of exhaled nitric oxide, spirometry, methacholine challenge, and sputum induction (cell counts and inflammatory mediator levels). Asthma control was assessed by using the Global Initiative for Asthma (GINA) classification and the Asthma Control Questionnaire (ACQ). The number of cough sounds was manually counted and expressed as coughs per hour (c/h).

RESULTS

Eighty-nine subjects with asthma (mean ± SD age, 57 ± 12 years; 57% female) were recruited. According to GINA criteria, 18 (20.2%) patients were classified as controlled, 39 (43.8%) partly controlled, and 32 (36%) uncontrolled; the median ACQ score was 1 (range, 0.0-4.4). The 6-item ACQ correlated with 24-h cough frequency (r = 0.40; P < .001), and patients with uncontrolled asthma (per GINA criteria) had higher median 24-h cough frequency (4.2 c/h; range, 0.3-27.6) compared with partially controlled asthma (1.8 c/h; range, 0.2-25.3; P = .01) and controlled asthma (1.7 c/h; range, 0.3-6.7; P = .002). Measures of airway inflammation were not significantly different between GINA categories and were not correlated with ACQ. In multivariate analyses, increasing cough frequency and worsening FEV1 independently predicted measures of asthma control.

CONCLUSIONS

Ambulatory cough frequency monitoring provides an objective assessment of asthma symptoms that correlates with standard measures of asthma control but not airflow obstruction or airway inflammation. Moreover, cough frequency and airflow obstruction represent independent dimensions of asthma control.

GWAS for executive function and processing speed suggests involvement of the CADM2 gene

To identify common variants contributing to normal variation in two specific domains of cognitive functioning, we conducted a genome-wide association study (GWAS) of executive functioning and information processing speed in non-demented older adults from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) consortium. Neuropsychological testing was available for 5429-32,070 subjects of European ancestry aged 45 years or older, free of dementia and clinical stroke at the time of cognitive testing from 20 cohorts in the discovery phase. We analyzed performance on the Trail Making Test parts A and B, the Letter Digit Substitution Test (LDST), the Digit Symbol Substitution Task (DSST), semantic and phonemic fluency tests, and the Stroop Color and Word Test. Replication was sought in 1311-21860 subjects from 20 independent cohorts. A significant association was observed in the discovery cohorts for the single-nucleotide polymorphism (SNP) rs17518584 (discovery P-value=3.12 × 10(-8)) and in the joint discovery and replication meta-analysis (P-value=3.28 × 10(-9) after adjustment for age, gender and education) in an intron of the gene cell adhesion molecule 2 (CADM2) for performance on the LDST/DSST. Rs17518584 is located about 170 kb upstream of the transcription start site of the major transcript for the CADM2 gene, but is within an intron of a variant transcript that includes an alternative first exon. The variant is associated with expression of CADM2 in the cingulate cortex (P-value=4 × 10(-4)). The protein encoded by CADM2 is involved in glutamate signaling (P-value=7.22 × 10(-15)), gamma-aminobutyric acid (GABA) transport (P-value=1.36 × 10(-11)) and neuron cell-cell adhesion (P-value=1.48 × 10(-13)). Our findings suggest that genetic variation in the CADM2 gene is associated with individual differences in information processing speed.

Transient receptor potential cation channel, subfamily V, member 4 and airway sensory afferent activation: Role of adenosine triphosphate

BACKGROUND

Sensory nerves innervating the airways play an important role in regulating various cardiopulmonary functions, maintaining homeostasis under healthy conditions and contributing to pathophysiology in disease states. Hypo-osmotic solutions elicit sensory reflexes, including cough, and are a potent stimulus for airway narrowing in asthmatic patients, but the mechanisms involved are not known. Transient receptor potential cation channel, subfamily V, member 4 (TRPV4) is widely expressed in the respiratory tract, but its role as a peripheral nociceptor has not been explored.

OBJECTIVE

We hypothesized that TRPV4 is expressed on airway afferents and is a key osmosensor initiating reflex events in the lung.

METHODS

We used guinea pig primary cells, tissue bioassay, in vivo electrophysiology, and a guinea pig conscious cough model to investigate a role for TRPV4 in mediating sensory nerve activation in vagal afferents and the possible downstream signaling mechanisms. Human vagus nerve was used to confirm key observations in animal tissues.

RESULTS

Here we show TRPV4-induced activation of guinea pig airway-specific primary nodose ganglion cells. TRPV4 ligands and hypo-osmotic solutions caused depolarization of murine, guinea pig, and human vagus and firing of Aδ-fibers (not C-fibers), which was inhibited by TRPV4 and P2X3 receptor antagonists. Both antagonists blocked TRPV4-induced cough.

CONCLUSION

This study identifies the TRPV4-ATP-P2X3 interaction as a key osmosensing pathway involved in airway sensory nerve reflexes. The absence of TRPV4-ATP-mediated effects on C-fibers indicates a distinct neurobiology for this ion channel and implicates TRPV4 as a novel therapeutic target for neuronal hyperresponsiveness in the airways and symptoms, such as cough.

A placebo-controlled trial of aprepitant for cough in lung cancer

2

Background: There are no evidence-based therapies for cough in lung cancer (LC).The neurokinin-1 (NK-1) pathway is implicated in cough. Aprepitant is an NK-1 antagonist used as an antiemetic. We assess aprepitant as an antitussive, using objective daytime ambulatory cough monitoring (ACM) as the primary endpoint. Methods: LC patients with a “bothersome” cough were enrolled on an exploratory single-arm randomised double-blind crossover trial and received 125mg aprepitant on day 1 and 80mg on days 2 and 3 or matched placebo capsules. After a 3 day wash out,patients crossed over to placebo or aprepitant for 3 days (days 7-9). They completed ACM and validated subjective cough tools. Results: 20 LC patients were enrolled between 7th Oct 2013-3rd Nov 2014; mean age 66 yrs (SD 7.69); 60% (n=12) female; 70% (n=14) ex, 25% (n=5) current and 5% (n=1) never smokers respectively. 20% (n=4), 55% (n=11) and 25% (n=5) had a performance status of 0, 1 and 2 respectively. The majority (80% n=16) had non-small cell LC; half (n=10) had advanced stage; 20% (n=4) were on anticancer therapy. Daytime cough frequency was 15.9 (95%CI 10.1-28.3 n=19), 12.8 (95% CI 8.7-18.8 n=18) and 16.2 (11.3-23.0 n=19) coughs/hr at baseline, on aprepitant and on placebo respectively: p=0.03. Visual analogue scale scores (range 0-100, high score=worse severity) were 57.0mm (95% CI 47.4-67.2 n=19), 40.8mm, (95%CI 34.3-47.3 n=18), and 49.8mm (95%CI 44.2-55.4 n=19) at baseline, on aprepitant and on placebo respectively: p=0.008. The Manchester Cough in Lung Cancer Scale score (range 1-50, high score = worse cough impact) was 25.2 (95%CI 23.0-28.0 n=19), 19.5 (95%CI 17.8-21.2 n=18) and 21.7 (20.3-23.1 n=18) at baseline, on aprepitant and on placebo respectively: p<0.001.There were no serious adverse events. Conclusions: This is the first trial to assess the efficacy of a novel antitussive using validated subjective and objective cough tools in LC and the first to investigate a centrally acting NK-1 antagonist in humans. Aprepitant treatment was associated with statistically significant improvements in objective and subjective scores. The NK-1 receptors may be key mediators in cough in LC. It is possible to run a robust trial using validated measures with clinically meaningful endpoints in a LC population. Clinical trial information: ISRCTN16200035.

Scleromyxedema secondary to hepatitis C virus and successfully treated with antiviral therapy

Scleromyxedema (SM) is a chronic and progressive fibromucinous disease with no known etiology. We report a patient with scleromyxedema associated with hepatitis C virus, successfully treated with interferon and ribavirin therapy.

Morphologic Characterization of Nerves in Whole-Mount Airway Biopsies

RATIONALE

Neuroplasticity of bronchopulmonary afferent neurons that respond to mechanical and chemical stimuli may sensitize the cough reflex. Afferent drive in cough is carried by the vagus nerve, and vagal afferent nerve terminals have been well defined in animals. Yet, both unmyelinated C fibers and particularly the morphologically distinct, myelinated, nodose-derived mechanoreceptors described in animals are poorly characterized in humans. To date there are no distinctive molecular markers or detailed morphologies available for human bronchopulmonary afferent nerves.

OBJECTIVES

Morphologic and neuromolecular characterization of the afferent nerves that are potentially involved in cough in humans.

METHODS

A whole-mount immunofluorescence approach, rarely used in human lung tissue, was used with antibodies specific to protein gene product 9.5 (PGP9.5) and, for the first time in human lung tissue, 200-kD neurofilament subunit.

MEASUREMENTS AND MAIN RESULTS

We have developed a robust technique to visualize fibers consistent with autonomic and C fibers and pulmonary neuroendocrine cells. A group of morphologically distinct, 200-kD neurofilament-immunopositive myelinated afferent fibers, a subpopulation of which did not express PGP9.5, was also identified.

CONCLUSIONS

PGP9.5-immunonegative nerves are strikingly similar to myelinated airway afferents, the cough receptor, and smooth muscle-associated airway receptors described in rodents. These have never been described in humans. Full description of human airway nerves is critical to the translation of animal studies to the clinical setting.

Extracellular vesicles and their synthetic analogues in aging and age-associated brain diseases

Multicellular organisms rely upon diverse and complex intercellular communications networks for a myriad of physiological processes. Disruption of these processes is implicated in the onset and propagation of disease and disorder, including the mechanisms of senescence at both cellular and organismal levels. In recent years, secreted extracellular vesicles (EVs) have been identified as a particularly novel vector by which cell-to-cell communications are enacted. EVs actively and specifically traffic bioactive proteins, nucleic acids, and metabolites between cells at local and systemic levels, modulating cellular responses in a bidirectional manner under both homeostatic and pathological conditions. EVs are being implicated not only in the generic aging process, but also as vehicles of pathology in a number of age-related diseases, including cancer and neurodegenerative and disease. Thus, circulating EVs-or specific EV cargoes-are being utilised as putative biomarkers of disease. On the other hand, EVs, as targeted intercellular shuttles of multipotent bioactive payloads, have demonstrated promising therapeutic properties, which can potentially be modulated and enhanced through cellular engineering. Furthermore, there is considerable interest in employing nanomedicinal approaches to mimic the putative therapeutic properties of EVs by employing synthetic analogues for targeted drug delivery. Herein we describe what is known about the origin and nature of EVs and subsequently review their putative roles in biology and medicine (including the use of synthetic EV analogues), with a particular focus on their role in aging and age-related brain diseases.

P2X3 receptor antagonist (AF-219) in refractory chronic cough: a randomised, double-blind, placebo-controlled phase 2 study

BACKGROUND

Preclinical studies suggest that P2X3 receptors are expressed by airway vagal afferent nerves and contribute to the hypersensitisation of sensory neurons. P2X3 receptors could mediate sensitisation of the cough reflex, leading to chronic cough. We aimed to investigate the efficacy of a first-in-class oral P2X3 antagonist, AF-219, to reduce cough frequency in patients with refractory chronic cough.

METHODS

We did a double-blind, placebo-controlled, two-period, crossover study at one UK centre. With a computer-generated sequence, we randomly assigned patients with refractory chronic cough to AF-219, 600 mg twice a day, or to placebo (1:1), and then, after a 2 week washout, assigned patients to receive the other treatment. Patients, health-care providers, and investigators were masked to sequence assignment. We assessed daytime cough frequency (primary endpoint) at baseline and after 2 weeks of treatment using 24 h ambulatory cough recordings. The primary analysis used a mixed effects model with the intention-to-treat population. This study was registered at ClinicalTrials.gov, number NCT01432730.

FINDINGS

Of 34 individuals assessed between Sept 22, 2011, and Nov 29, 2012, we randomly assigned 24 patients (mean age 54·5 years; SD 11·1). In the observed case analysis, cough frequency was reduced by 75% when patients were allocated to AF-219 compared when allocated to placebo (p=0·0003). Daytime cough frequency fell from a mean 37 coughs per h (SD 32) to 11 (8) coughs per h after AF-219 treatment versus 65 (163) coughs per h to 44 (51) coughs per h after placebo. Six patients withdrew before the end of the study because of taste disturbances, which were reported by all patients taking AF-219.

INTERPRETATION

P2X3 receptors seem to have a key role in mediation of cough neuronal hypersensitivity. Antagonists of P2X3 receptors such as AF-219 are a promising new group of antitussives.

FUNDING

Afferent Pharmaceuticals.

Anatomy and neurophysiology of cough: CHEST Guideline and Expert Panel report

Bronchopulmonary C-fibers and a subset of mechanically sensitive, acid-sensitive myelinated sensory nerves play essential roles in regulating cough. These vagal sensory nerves terminate primarily in the larynx, trachea, carina, and large intrapulmonary bronchi. Other bronchopulmonary sensory nerves, sensory nerves innervating other viscera, as well as somatosensory nerves innervating the chest wall, diaphragm, and abdominal musculature regulate cough patterning and cough sensitivity. The responsiveness and morphology of the airway vagal sensory nerve subtypes and the extrapulmonary sensory nerves that regulate coughing are described. The brainstem and higher brain control systems that process this sensory information are complex, but our current understanding of them is considerable and increasing. The relevance of these neural systems to clinical phenomena, such as urge to cough and psychologic methods for treatment of dystussia, is high, and modern imaging methods have revealed potential neural substrates for some features of cough in the human.

Weak peristalsis with large breaks in chronic cough: association with poor esophageal clearance

BACKGROUND

Gastroesophageal reflux plays an important role in chronic cough (CC). Whether disturbed esophageal motility contributes to increased esophageal reflux exposure or interferes with swallowed bolus clearance is unclear. This study used high resolution esophageal manometry and impedance (HRIM) together with Chicago Classification, and 24-h impedance pH (MII/pH) to address these questions in patients with CC compared with heartburn (HB).

METHODS

A retrospective review of 32 patients with CC (mean age 57 [95% CI: 52-62] years) and 32 patients with symptoms of HB (55 [52-62] years) referred for HRIM and MII/pH between September 2012 and September 2013 was undertaken.

KEY RESULTS

Weak peristalsis with large breaks (WPLBs) was observed in 34% of CC patients compared with only 12% of HB patients (p = 0.027). Pathological acid exposure time (AET) was identified in 81% of CC patients with WPLBs compared with 29% without (p = 0.011). Increased AET was associated with prolonged clearance time of refluxed events (p = 0.006) rather than increased number of events. AET correlated with the percentage of peristaltic events with large breaks in CC (ρ = 0.467, p = 0.007). Similar data were obtained for total bolus (acid and non-acid) exposure time. Only one of the CC patients with WPLBs exhibited complete bolus transit (CBT) on swallowing compared with 81% without WPLBs (p < 0.001). Moreover, the percentage of peristaltic events associated with CBT negatively correlated with the percentage of peristaltic events with large breaks (r = -0.653, p < 0.001) in CC.

CONCLUSIONS & INFERENCES

One-third of CC patients exhibit WPLBs, which directly impacts on clearance of refluxed events and bolus's swallowed. These observations may have important implications for esophageal-bronchial interaction in CC.

Genetic contributions to variation in general cognitive function: a meta-analysis of genome-wide association studies in the CHARGE consortium (N=53949)

General cognitive function is substantially heritable across the human life course from adolescence to old age. We investigated the genetic contribution to variation in this important, health- and well-being-related trait in middle-aged and older adults. We conducted a meta-analysis of genome-wide association studies of 31 cohorts (N=53,949) in which the participants had undertaken multiple, diverse cognitive tests. A general cognitive function phenotype was tested for, and created in each cohort by principal component analysis. We report 13 genome-wide significant single-nucleotide polymorphism (SNP) associations in three genomic regions, 6q16.1, 14q12 and 19q13.32 (best SNP and closest gene, respectively: rs10457441, P=3.93 × 10(-9), MIR2113; rs17522122, P=2.55 × 10(-8), AKAP6; rs10119, P=5.67 × 10(-9), APOE/TOMM40). We report one gene-based significant association with the HMGN1 gene located on chromosome 21 (P=1 × 10(-6)). These genes have previously been associated with neuropsychiatric phenotypes. Meta-analysis results are consistent with a polygenic model of inheritance. To estimate SNP-based heritability, the genome-wide complex trait analysis procedure was applied to two large cohorts, the Atherosclerosis Risk in Communities Study (N=6617) and the Health and Retirement Study (N=5976). The proportion of phenotypic variation accounted for by all genotyped common SNPs was 29% (s.e.=5%) and 28% (s.e.=7%), respectively. Using polygenic prediction analysis, ~1.2% of the variance in general cognitive function was predicted in the Generation Scotland cohort (N=5487; P=1.5 × 10(-17)). In hypothesis-driven tests, there was significant association between general cognitive function and four genes previously associated with Alzheimer's disease: TOMM40, APOE, ABCG1 and MEF2C.