Genomic attributes of airway commensal bacteria and mucosa

Microbial communities at the airway mucosal barrier are conserved and highly ordered, in likelihood reflecting co-evolution with human host factors. Freed of selection to digest nutrients, the airway microbiome underpins cognate management of mucosal immunity and pathogen resistance. We show here the initial results of systematic culture and whole-genome sequencing of the thoracic airway bacteria, identifying 52 novel species amongst 126 organisms that constitute 75% of commensals typically present in heathy individuals. Clinically relevant genes encode antimicrobial synthesis, adhesion and biofilm formation, immune modulation, iron utilisation, nitrous oxide (NO) metabolism and sphingolipid signalling. Using whole-genome content we identify dysbiotic features that may influence asthma and chronic obstructive pulmonary disease. We match isolate gene content to transcripts and metabolites expressed late in airway epithelial differentiation, identifying pathways to sustain host interactions with microbiota. Our results provide a systematic basis for decrypting interactions between commensals, pathogens, and mucosa in lung diseases of global significance.

Airway microbial communities, smoking and asthma in a general population sample

BACKGROUND

Normal airway microbial communities play a central role in respiratory health but are poorly characterized. Cigarette smoking is the dominant global environmental influence on lung function, and asthma has become the most prevalent chronic respiratory disease worldwide. Both conditions have major microbial components that are incompletely defined.

METHODS

We investigated airway bacterial communities in a general population sample of 529 Australian adults. Posterior oropharyngeal swabs were analyzed by sequencing of the 16S rRNA gene. The microbiota were characterized according to their prevalence, abundance and network memberships.

FINDINGS

The microbiota were similar across the general population, and were strongly organized into co-abundance networks. Smoking was associated with diversity loss, negative effects on abundant taxa, profound alterations to network structure and expansion of Streptococcus spp. By contrast, the asthmatic microbiota were selectively affected by an increase in Neisseria spp. and by reduced numbers of low abundance but prevalent organisms.

INTERPRETATION

Our study shows that the healthy airway microbiota in this population were contained within a highly structured ecosystem, suggesting balanced relationships between the microbiome and human host factors. The marked abnormalities in smokers may contribute to chronic obstructive pulmonary disease (COPD) and lung cancer. The narrow spectrum of abnormalities in asthmatics encourages investigation of damaging and protective effects of specific bacteria.

FUNDING

The study was funded by the Asmarley Trust and a Wellcome Joint Senior Investigator Award to WOCC and MFM (WT096964MA and WT097117MA). The Busselton Healthy Ageing Study is supported by the Government of Western Australia (Office of Science, Department of Health) the City of Busselton, and private donations.

Asbestos-related diseases

Knowledge of asbestos-related diseases has been accumulating for over one hundred years as the industrial value of asbestos was recognised for the strength of its fibres and their resistance to destruction, resulting in increasing production and use until the multiple health effects have become apparent. Deposition in the lung parenchyma results in an inflammatory/progressively fibrotic response, with impaired gas exchange and reduced lung compliance ('asbestosis'), causing progressive dyspnoea and respiratory failure for which only palliation is indicated, although anti-fibrotic agents used for idiopathic usual interstitial pneumonitis remain to be evaluated. Benign pleural effusion, diffuse pleural fibrosis (occasionally with associated rolled atelectasis) and pleural plaques are the non-malignant pleural diseases that result from fibres reaching the pleura. But the main issues that led to the ban on asbestos in industry are those of malignancy: lung cancer, malignant mesothelioma (MM) of the pleura and MM of the peritoneum. Bronchogenic carcinoma risk from asbestos exposure is dose-dependent and multiplies the risk attributable to tobacco smoking. The principles of treatment are as for all cases of lung cancer. Low-dose computed tomography screening of exposed people can detect early-stage, non-small cell cancers, with improved survival. The amphibole varieties of asbestos are much more potent causes of MM than chrysotile, and the risk increases exponentially for 40-50 years following first exposure. As MM is non-resectable and poorly responsive to chemotherapy and radiotherapy, curative treatment is not possible and screening not justified.

Respiratory surveillance for coal mine dust and artificial stone exposed workers in Australia and New Zealand: A position statement from the Thoracic Society of Australia and New Zealand

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.

Measurement of urinary 1-aminopyrene and 1-hydroxypyrene as biomarkers of exposure to diesel particulate matter in gold miners

Metabolites of polycyclic aromatic hydrocarbons measured in human samples are often used as biomarkers of exposure to diesel engine exhaust (DEE). The aim of this study was to assess the changes in urinary levels of 1-aminopyrene (1-AP) and 1-hydroxypyrene (1-OHP) and their relationship with Elemental Carbon (EC), as a component of diesel engine exhaust exposure, among a hard-rock gold-mining population. Urine samples were collected at the beginning and end of a 12-hour work shift from 100 underground and above ground gold miners. Miners were fitted with personal exposure monitoring equipment to quantify exposure to DEE, measured as Elemental Carbon (EC), across their 12-hour work shift. General linear regression assessed associations of the post-shift urinary 1-AP and 1-OHP concentrations with EC, controlling for age, gender, the pre-shift biomarker level, Body Mass Index (BMI), days on current shift, time in mining, smoking status and second-hand smoke exposure. The concentrations of 1-AP and 1-OHP increased significantly across a 12-hour mining work shift. Moreover, consistent with the sensitivity analysis, the concentration of 1-AP was significantly associated with EC after adjustments. Urinary 1-OHP, but not 1-AP was significantly associated with current smoking. Urinary 1-AP may be a more robust and specific biomarker of DEE than 1-OHP.

Genome Analyses of >200,000 Individuals Identify 58 Loci for Chronic Inflammation and Highlight Pathways that Link Inflammation and Complex Disorders

C-reactive protein (CRP) is a sensitive biomarker of chronic low-grade inflammation and is associated with multiple complex diseases. The genetic determinants of chronic inflammation remain largely unknown, and the causal role of CRP in several clinical outcomes is debated. We performed two genome-wide association studies (GWASs), on HapMap and 1000 Genomes imputed data, of circulating amounts of CRP by using data from 88 studies comprising 204,402 European individuals. Additionally, we performed in silico functional analyses and Mendelian randomization analyses with several clinical outcomes. The GWAS meta-analyses of CRP revealed 58 distinct genetic loci (p < 5 × 10-8). After adjustment for body mass index in the regression analysis, the associations at all except three loci remained. The lead variants at the distinct loci explained up to 7.0% of the variance in circulating amounts of CRP. We identified 66 gene sets that were organized in two substantially correlated clusters, one mainly composed of immune pathways and the other characterized by metabolic pathways in the liver. Mendelian randomization analyses revealed a causal protective effect of CRP on schizophrenia and a risk-increasing effect on bipolar disorder. Our findings provide further insights into the biology of inflammation and could lead to interventions for treating inflammation and its clinical consequences.

Asbestos exposure and histological subtype of malignant mesothelioma

BACKGROUND

Malignant mesothelioma (MM) has distinct histological subtypes (epithelioid, sarcomatoid and biphasic) with variable behaviour and prognoses. It is well recognised that survival time varies with the histological subtype of MM. It is not known, however, if asbestos exposure characteristics (type of asbestos, degree of exposure) are associated with different histological subtypes.

AIM

To determine if the pathological MM subtype is associated with the type of asbestos or the attributes of asbestos exposure.

METHODS

Cases of MM for the period 1962 until 2012, their main histological subtype and their most significant source of asbestos exposure were collected from the Western Australian Mesothelioma Registry. Exposure characteristics included, degree of asbestos exposure (including total days exposed, years since first exposure and, for crocidolite only, calculated cumulative exposure), source of exposure (occupational or environmental), form of asbestos handled (raw or processed) and type of asbestos (crocidolite only or mixed fibres).

RESULTS

Patients with the biphasic subtype were more likely to have occupational exposure (OR 1.83, 1.12 to 2.85) and exposure to raw fibres (OR 1.58, 1.19 to 2.10). However, differences between subtypes in the proportions with these different exposure characteristics were small and unlikely to be biologically relevant. Other indicators of asbestos exposure were not associated with the histological subtype of mesothelioma.

CONCLUSIONS

There was no strong evidence of a consistent role of asbestos exposure indicators in determining the histological subtype of MM.

ENOX2-based early detection (ONCOblot) of asbestos-induced malignant mesothelioma 4-10 years in advance of clinical symptoms

Background

Malignant mesothelioma is an aggressive, almost uniformly fatal tumor, caused primarily by exposure to asbestos. In this study, serum presence of mesothelioma-specific protein transcript variants of ecto-nicotinamide adenine dinucleotide oxidase disulfide-thiol exchanger 2 (ENOX2), a recently identified marker of malignancy, were investigated using the ONCOblot tissue of origin cancer detection test.

Methods

Sequential serum samples collected from asbestos-exposed individuals prior to the development of frank mesothelioma were assayed for ENOX2 presence by 2-D gel immunoblot analysis to determine how long in advance of clinical symptoms mesothelioma-specific ENOX2 transcript variants could be detected.

Results

Two mesothelioma-specific ENOX2 protein transcript variants were detected in the serum of asbestos-exposed individuals 4–10 years prior to clinical diagnosis of malignant mesothelioma (average 6.2 years). Either one or both ENOX2 protein transcript variants indicative of malignant mesothelioma were absent in 14 of 15 subjects diagnosed with benign pleural plaques either with or without accompanying asbestosis.

Conclusions

In a population of asbestos-exposed subjects who eventually developed malignant mesothelioma, ENOX2 protein transcript variants characteristic of malignant mesothelioma were present in serum 4–10 years in advance of clinical symptoms. As with all biomarker studies, these observations require validation in a larger, independent cohort of patients and should include prospective as well as retrospective sampling.

A phase 1b clinical trial of the CD40-activating antibody CP-870,893 in combination with cisplatin and pemetrexed in malignant pleural mesothelioma

BACKGROUND

Data from murine models suggest that CD40 activation may synergize with cytotoxic chemotherapy. We aimed to determine the maximum tolerated dose (MTD) and toxicity profile and to explore immunological biomarkers of the CD40-activating antibody CP-870,893 with cisplatin and pemetrexed in patients with malignant pleural mesothelioma (MPM).

PATIENTS AND METHODS

Eligible patients had confirmed MPM, ECOG performance status 0-1, and measurable disease. Patients received cisplatin 75 mg/m(2) and pemetrexed 500 mg/m(2) on day 1 and CP-870,893 on day 8 of a 21-day cycle for maximum 6 cycles with up to 6 subsequent cycles single-agent CP-870,893. Immune cell subset changes were examined weekly by flow cytometry.

RESULTS

Fifteen patients were treated at three dose levels. The MTD of CP-870,893 was 0.15 mg/kg, and was exceeded at 0.2 mg/kg with one grade 4 splenic infarction and one grade 3 confusion and hyponatraemia. Cytokine release syndrome (CRS) occurred in most patients (80%) following CP-870,893. Haematological toxicities were consistent with cisplatin and pemetrexed chemotherapy. Six partial responses (40%) and 9 stable disease (53%) as best response were observed. The median overall survival was 16.5 months; the median progression-free survival was 6.3 months. Three patients survived beyond 30 months. CD19+ B cells decreased over 6 cycles of chemoimmunotherapy (P < 0.001) with a concomitant increase in the proportion of CD27+ memory B cells (P < 0.001) and activated CD86+CD27+ memory B cells (P < 0.001), as an immunopharmacodynamic marker of CD40 activation.

CONCLUSIONS

CP-870,893 with cisplatin and pemetrexed is safe and tolerable at 0.15 mg/kg, although most patients experience CRS. While objective response rates are similar to chemotherapy alone, three patients achieved long-term survival.

AUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRY NUMBER

ACTRN12609000294257.

ALN-RSV01 for prevention of bronchiolitis obliterans syndrome after respiratory syncytial virus infection in lung transplant recipients

BACKGROUND

Respiratory syncytial virus (RSV) infection in lung transplant (LTx) patients is associated with an increased incidence of bronchiolitis obliterans syndrome (BOS). ALN-RSV01 is a small interfering RNA targeting RSV replication that was shown in an earlier Phase 2a trial to be safe and to reduce the incidence of BOS when compared with placebo.

METHODS

We performed a Phase 2b randomized, double-blind, placebo-controlled trial in RSV-infected LTx patients to examine the impact of ALN-RSV01 on the incidence of new or progressive BOS. Subjects were randomized (1:1) to receive aerosolized ALN-RSV01 or placebo daily for 5 days.

RESULTS

Of 3,985 symptomatic patients screened, 218 were RSV-positive locally, of whom 87 were randomized to receive ALN-RSV01 or placebo (modified intention-to-treat [mITT] cohort). RSV infection was confirmed by central laboratory in 77 patients (ALN-RSV01, n = 44; placebo, n = 33), which comprised the primary analysis cohort (central mITT [mITTc]). ALN-RSV01 was found to be safe and well-tolerated. At Day 180, in ALN-RSV01-treated patients, compared with placebo, in the mITTc cohort there was a trend toward a decrease in new or progressive BOS (13.6% vs 30.3%, p = 0.058), which was significant in the per-protocol cohort (p = 0.025). Treatment effect was enhanced when ALN-RSV01 was started <5 days from symptom onset, and was observed even without ribavirin treatment. There was no significant impact on viral parameters or symptom scores.

CONCLUSIONS

These results confirm findings of the earlier Phase 2a trial and provide further support that ALN-RSV01 reduces the risk of BOS after RSV in LTx recipients.

The mental health of asbestos-exposed subjects with pleural abnormalities

PURPOSE

To examine the effect of knowledge of radiographic abnormalities on the mental health of asbestos-exposed people with and without pleural abnormalities.

METHODS

Subjects were former asbestos mine and mill workers and residents of the mining town who had participated in an annual health review program. Pleural abnormalities (pleural plaques, diffuse pleural thickening and asbestosis) were determined from plain chest X-rays. All Participants completed a questionnaire on mental health status (SF-12) and locus of control (LOC).

RESULTS

There were no significant differences between asbestos-exposed people with and without radiographic abnormalities for either the SF-12 mental health score or LOC. However, the asbestos-exposed cohorts had lower mental health scores compared with a random sample of the local population.

CONCLUSION

The presence of pleural abnormalities did not further affect the mental health of asbestos-exposed people beyond a decrement associated with exposure per se.

Genome-wide association study of body mass index in 23 000 individuals with and without asthma

BACKGROUND

Both asthma and obesity are complex disorders that are influenced by environmental and genetic factors. Shared genetic factors between asthma and obesity have been proposed to partly explain epidemiological findings of co-morbidity between these conditions.

OBJECTIVE

To identify genetic variants that are associated with body mass index (BMI) in asthmatic children and adults, and to evaluate if there are differences between the genetics of BMI in asthmatics and healthy individuals.

METHODS

In total, 19 studies contributed with genome-wide analysis study (GWAS) data from more than 23 000 individuals with predominantly European descent, of whom 8165 are asthmatics.

RESULTS

We report associations between several DENND1B variants (P = 2.2 × 10(-7) for rs4915551) on chromosome 1q31 and BMI from a meta-analysis of GWAS data using 2691 asthmatic children (screening data). The top DENND1B single nucleotide polymorphisms(SNPs) were next evaluated in seven independent replication data sets comprising 2014 asthmatics, and rs4915551 was nominally replicated (P < 0.05) in two of the seven studies and of borderline significance in one (P = 0.059). However, strong evidence of effect heterogeneity was observed and overall, the association between rs4915551 and BMI was not significant in the total replication data set, P = 0.71. Using a random effects model, BMI was overall estimated to increase by 0.30 kg/m(2) (P = 0.01 for combined screening and replication data sets, N = 4705) per additional G allele of this DENND1BSNP. FTO was confirmed as an important gene for adult and childhood BMI regardless of asthma status.

CONCLUSIONS AND CLINICAL RELEVANCE

DENND1B was recently identified as an asthma susceptibility gene in a GWAS on children, and here, we find evidence that DENND1B variants may also be associated with BMI in asthmatic children. However, the association was overall not replicated in the independent data sets and the heterogeneous effect of DENND1B points to complex associations with the studied diseases that deserve further study.

The Diagnosis and Attribution of Asbestos-related Diseases in an Australian Context: Report of the Adelaide Workshop on Asbestos-related Diseases. October 6–7, 2000

Predictions of future cases of mesothelioma in Australia to the year 2020 are in the order of a total of 10,000 new cases. Compensation claims are testing the attribution in a particular case between occupational asbestos exposure and lung cancer. The cost of the problem necessitates clarifying and standardizing the criteria for a confident diagnosis of asbestos-related disease. The possibility of differences in criteria that determine attribution of asbestos to a disease prompted a consensus meeting of pathologists, epidemiologists, physicians, oncologists, radiologists, and others to define current thinking and to agree on an Australian document based on the scientific evidence for establishing diagnoses and attribution data of asbestos-related diseases in Australia. The participants' findings are reported.

Gastro-oesophageal reflux and respiratory symptoms in Busselton adults: the effects of bodyweight and sleep apnoea

BACKGROUND/AIM

Respiratory symptoms and gastro-oesophageal reflux disease (GORD) are common within the general population. Although a number of epidemiological studies have addressed their relationship, none has investigated the confounding effects of body mass index (BMI) and obstructive sleep apnoea (OSA), both of which are associated with reflux.

METHODS

Men and women (2700) from the 2005-2007 cross-sectional Busselton health survey were included. Questionnaire data included demography, information on general health, asthma, cough, wheeze, dyspnoea and reflux symptoms (never, monthly or less often and weekly or more often). BMI, risk of OSA (Berlin questionnaire definition), spirometry and airway hyperresponsiveness (AHR) were recorded. The effects of BMI and OSA on the relationship between respiratory and reflux symptoms were examined using logistic regression models, expressed as adjusted odds ratios for risk of respiratory symptoms by reflux symptom category.

RESULTS

Fifty per cent had reflux symptoms (5-10% weekly or more often). Reflux symptoms had strong positive, dose-related associations with cough/phlegm, breathlessness, chest tightness and wheeze in the last 12 months (P < 0.001), but were not related to diagnosed asthma or AHR. Twenty-three per cent were at high risk of OSA and 63% had a BMI of >25 (22% > 30). Increased weight or high risk of OSA did not affect the relationship between respiratory symptoms and reflux symptoms.

CONCLUSION

The relationship between reflux and respiratory symptoms was independent of BMI, high risk of OSA or AHR. These findings suggest that reflux contributes directly to respiratory symptoms.

No dose-dependent increase in fracture risk after long-term exposure to high doses of retinol or beta-carotene

Uncertainty remains over whether or not high intakes of retinol or vitamin A consumed through food or supplements may increase fracture risk. This intervention study found no increase in fracture risk among 2,322 adults who took a controlled, high-dose retinol supplement (25,000 IU retinyl palmitate/day) for as long as 16 years. There was some evidence that beta-carotene supplementation decreased fracture risk in men.

INTRODUCTION

There is conflicting epidemiological evidence regarding high intakes of dietary or supplemental retinol and an increased risk for bone fracture. We examined fracture risk in a study administering high doses of retinol and beta-carotene (BC) between 1990 and 2007.

METHODS

The Vitamin A Program was designed to test the efficacy of retinol and BC supplements in preventing malignancies in persons previously exposed to blue asbestos. Participants were initially randomised to 7.5 mg retinol equivalents (RE)/day as retinyl palmitate, 30 mg/day BC or 0.75 mg/day BC from 1990 to 1996; after which, all participants received 7.5 mg RE/day. Fractures were identified by questionnaire and hospital admission data up until 2006. Risk of any fracture or osteoporotic fracture according to cumulative dose of retinol and BC supplementation was examined using conditional logistic regression models adjusting for age, sex, smoking, body mass index, medication use and previous fracture.

RESULTS

Supplementation periods ranged from 1 to 16 years. Of the 2,322 (664 females and 1,658 males) participants, 187 experienced 237 fractures. No associations were observed between cumulative dose of retinol and risk for any fracture (OR per 10 g RE=0.83; 95% CI, 0.63-1.08) or osteoporotic fracture (OR per 10 g RE=0.95; 95% CI 0.64-1.40). Among men, cumulative dose of BC was associated with a slightly reduced risk of any fracture (OR per 10 g=0.89; 95% CI 0.81-0.98) and osteoporotic fracture (OR per 10 g=0.84; 95% CI 0.72-0.97).

CONCLUSIONS

This study observed no increases in fracture risk after long-term supplementation with high doses of retinol and/or beta-carotene.

Postmortem findings of malignant pleural mesothelioma: a two-center study of 318 patients

BACKGROUND

Malignant pleural mesothelioma (MPM) is an incurable cancer with a rising incidence. MPM is often perceived as a locally invasive cancer, and the exact cause of death is poorly understood.This two-center study describes the anatomic features of patients with MPM at postmortem.

METHODS

The Western Australia Mesothelioma Registry (Australia) and Coroner’s Office reports from the Avon region (England) were interrogated for the postmortem records of confirmed mesothelioma cases.

RESULTS

Postmortem records of 318 patients with pleural mesothelioma (169 from Western Australia and 149 from Avon) were identified. Most patients (91.5%) were men (mean age, 68.4 ± 11.5 years), and MPM was right-sided in 55.3%. Extrapleural dissemination of tumor was found in 87.7% of cases and lymph node involvement in 53.3%. Tumor dissemination in extra thoracicsites was common (55.4% of patients), and almost all organs were involved, including liver(31.9%), spleen (10.8%), thyroid (6.9%), and the brain (3.0%). Pulmonary emboli were found in 6% of cases and considered as directly contributing to death in 13 patients (4.1%). The precise cause of death could only be determined in 63 (19.8%) cases even after postmortem. The BMI was significantly lower in cases that had no identifiable anatomic cause of death at postmortem(18.8 ± 4.3 vs 21.0 ± 4.7, P = .034).

CONCLUSIONS

In this largest, to our knowledge, postmortem series on MPM, extrathoracic dissemination of mesothelioma was common and often under recognized. No anatomic cause of death was identified in the majority of patients even at autopsy, raising the possibility of physiologic and metabolic causes of death.

Pleurodesis outcome in malignant pleural mesothelioma

Few data exist on the pleurodesis outcome in patients with malignant pleural mesothelioma (MPM). A retrospective review of the Western Australian Mesothelioma Registry over 5 years revealed 390 evaluable patients. Only a subset of patients (42.3%) underwent pleurodesis, surgically (n=78) or by bedside instillation of sclerosants (n=87). Surgical pleurodesis showed no advantages over bedside pleurodesis in efficacy (32% vs 31% failures requiring further drainage, p=0.98), patient survival (p=0.52) or total time spent in hospital from procedure till death (p=0.36). No clinical, biochemical or radiographic parameters tested adequately predict pleurodesis outcome.

Genome-wide association study to identify genetic determinants of severe asthma

BACKGROUND

The genetic basis for developing asthma has been extensively studied. However, association studies to date have mostly focused on mild to moderate disease and genetic risk factors for severe asthma remain unclear.

OBJECTIVE

To identify common genetic variants affecting susceptibility to severe asthma.

METHODS

A genome-wide association study was undertaken in 933 European ancestry individuals with severe asthma based on Global Initiative for Asthma (GINA) criteria 3 or above and 3346 clean controls. After standard quality control measures, the association of 480 889 genotyped single nucleotide polymorphisms (SNPs) was tested. To improve the resolution of the association signals identified, non-genotyped SNPs were imputed in these regions using a dense reference panel of SNP genotypes from the 1000 Genomes Project. Then replication of SNPs of interest was undertaken in a further 231 cases and 1345 controls and a meta-analysis was performed to combine the results across studies.

RESULTS

An association was confirmed in subjects with severe asthma of loci previously identified for association with mild to moderate asthma. The strongest evidence was seen for the ORMDL3/GSDMB locus on chromosome 17q12-21 (rs4794820, p=1.03×10((-8)) following meta-analysis) meeting genome-wide significance. Strong evidence was also found for the IL1RL1/IL18R1 locus on 2q12 (rs9807989, p=5.59×10((-8)) following meta-analysis) just below this threshold. No novel loci for susceptibility to severe asthma met strict criteria for genome-wide significance.

CONCLUSIONS

The largest genome-wide association study of severe asthma to date was carried out and strong evidence found for the association of two previously identified asthma susceptibility loci in patients with severe disease. A number of novel regions with suggestive evidence were also identified warranting further study.

Malignant mesotheliomas in former miners and millers of crocidolite at Wittenoom (Western Australia) after more than 50 years follow-up

Background:

To report the number of malignant pleural and peritoneal mesotheliomas that have occurred in former Wittenoom crocidolite workers to the end of 2008, to compare this with earlier predictions, and to relate the mesothelioma rate to amount of exposure.

Methods:

A group of 6489 men and 419 women who had worked for the company operating the former Wittenoom crocidolite mine and mill at some time between 1943 and 1966 have been followed up throughout Australia and Italy to the end of 2008.

Results:

The cumulative number of mesotheliomas up to 2008 was 316 in men (268 pleural, 48 peritoneal) and 13 (all pleural) in women. There had been 302 deaths with mesothelioma in men and 13 in women, which was almost 10% of all known deaths. Mesothelioma rate, both pleural and peritoneal, increased with time since first exposure and appeared to reach a plateau after about 40 to 50 years. The mesothelioma rate increased with amount of exposure and the peritoneal mesotheliomas occurred preferentially in the highest exposure group, 37% compared with 15% overall.

Conclusion:

By the end of 2008, the number of mesothelioma deaths had reached 4.7% for all the male workers and 3.1% for the females. Over the past 8 years the numbers were higher than expected. It is predicted that about another 60 to 70 deaths with mesothelioma may occur in men by 2020.