Bird flight behavior, collision risk and mitigation options at high-speed railway viaducts.

High-speed railway (HSR) networks are rapidly expanding and are predicted to continue to grow over coming decades. However, there is scant knowledge of their environmental impacts. Their possible effects on bird mortality, particularly at viaducts, gives especial cause for concern. This work presents the results of a nine-month monitoring of bird activity in the vicinity of three HSR viaducts in Central Spain. The study focused on the effects of the infrastructure regarding bird frequentation of the site and on bird flight activity in the danger zone for collision with passing trains. The findings show (i) that bird communities may differ markedly between sites and (ii) that bird activity increases near the railway together with changes in relative species abundances. Furthermore, (iii) birds show a significant tendency to avoid flying across the danger zone, but (iv) all kinds of birds are at a real risk of collisions with trains at viaducts. The greatest danger is at viaduct extremes rather than in their central section, particularly during gusts of wind and for small or medium-sized birds. It also appears that relatively low viaducts might pose greater risk. In practical terms, these results (i) emphasise the need for thorough prior prospection of bird species present, and their flight patterns, where new viaducts are to be built, (ii) show that there is a real risk of bird collisions with trains at viaducts, which should be mitigated, with particular attention due to viaduct extremes and areas where their height is not much above the surrounding vegetation and (iii) strongly indicate the need to minimise viaduct features that may attract birds to them, for example as potential nest sites.

Paradoxical effects of cigarette smoke and COPD on SARS-CoV-2 infection and disease.

BACKGROUND: How cigarette smoke (CS) and chronic obstructive pulmonary disease (COPD) affect severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection and severity is controversial. We investigated the effects of COPD and CS on the expression of SARS-CoV-2 entry receptor ACE2 in vivo in COPD patients and controls and in CS-exposed mice, and the effects of CS on SARS-CoV-2 infection in human bronchial epithelial cells in vitro. METHODS: We quantified: (1) pulmonary ACE2 protein levels by immunostaining and ELISA, and both ACE2 and/or TMPRSS2 mRNA levels by RT-qPCR in two independent human cohorts; and (2) pulmonary ACE2 protein levels by immunostaining and ELISA in C57BL/6 WT mice exposed to air or CS for up to 6 months. The effects of CS exposure on SARS-CoV-2 infection were evaluated after in vitro infection of Calu-3 cells and differentiated human bronchial epithelial cells (HBECs), respectively. RESULTS: ACE2 protein and mRNA levels were decreased in peripheral airways from COPD patients versus controls but similar in central airways. Mice exposed to CS had decreased ACE2 protein levels in their bronchial and alveolar epithelia versus air-exposed mice. CS treatment decreased viral replication in Calu-3 cells, as determined by immunofluorescence staining for replicative double-stranded RNA (dsRNA) and western blot for viral N protein. Acute CS exposure decreased in vitro SARS-CoV-2 replication in HBECs, as determined by plaque assay and RT-qPCR. CONCLUSIONS: ACE2 levels were decreased in both bronchial and alveolar epithelial cells from COPD patients versus controls, and from CS-exposed versus air-exposed mice. CS-pre-exposure potently inhibited SARS-CoV-2 replication in vitro. These findings urge to investigate further the controversial effects of CS and COPD on SARS-CoV-2 infection.

Reconciling livestock production and wild herbivore conservation: challenges and opportunities.

Increasing food security and preventing further loss of biodiversity are two of humanity's most pressing challenges. Yet, efforts to address these challenges often lead to situations of conflict between the interests of agricultural production and those of biodiversity conservation. Here, we focus on conflicts between livestock production and the conservation of wild herbivores, which have received little attention in the scientific literature. We identify four key socio-ecological challenges underlying such conflicts, which we illustrate using a range of case studies. We argue that addressing these challenges will require the implementation of co-management approaches that promote the participation of relevant stakeholders in processes of ecological monitoring, impact assessment, decision-making, and active knowledge sharing.

Paradoxical effects of cigarette smoke and COPD on SARS-CoV2 infection and disease.

INTRODUCTION: How cigarette smoke (CS) and chronic obstructive pulmonary disease (COPD) affect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and severity is controversial. We investigated the protein and mRNA expression of SARS-CoV-2 entry receptor ACE2 and proteinase TMPRSS2 in lungs from COPD patients and controls, and lung tissue from mice exposed acutely and chronically to CS. Also, we investigated the effects of CS exposure on SARS-CoV-2 infection in human bronchial epithelial cells. METHODS: In Cohort 1, ACE2-positive cells were quantified by immunostaining in FFPE sections from both central and peripheral airways. In Cohort 2, we quantified pulmonary ACE2 protein levels by immunostaining and ELISA, and both ACE2 and TMPRSS2 mRNA levels by RT-qPCR. In C57BL/6 WT mice exposed to air or CS for up to 6 months, pulmonary ACE2 protein levels were quantified by triple immunofluorescence staining and ELISA. The effects of CS exposure on SARS-CoV-2 infection were evaluated after 72hr in vitro infection of Calu-3 cells. After SARS-CoV-2 infection, the cells were fixed for IF staining with dsRNA-specific J2 monoclonal Ab, and cell lysates were harvested for WB of viral nucleocapsid (N) protein. Supernatants (SN) and cytoplasmic lysates were obtained to measure ACE2 levels by ELISA. RESULTS: In both human cohorts, ACE2 protein and mRNA levels were decreased in peripheral airways from COPD patients versus both smoker and NS controls, but similar in central airways. TMPRSS2 levels were similar across groups. Mice exposed to CS had decreased ACE2 protein levels in their bronchial and alveolar epithelia versus air-exposed mice exposed to 3 and 6 months of CS. In Calu3 cells in vitro, CS-treatment abrogated infection to levels below the limit of detection. Similar results were seen with WB for viral N protein, showing peak viral protein synthesis at 72hr. CONCLUSIONS: ACE2 levels were decreased in both bronchial and alveolar epithelial cells from uninfected COPD patients versus controls, and from CS-exposed versus air-exposed mice. CS-pre-treatment did not affect ACE2 levels but potently inhibited SARS-CoV-2 replication in this in vitro model. These findings urge to further investigate the controversial effects of CS and COPD on SARS-CoV2 infection.

Color illusions also deceive CNNs for low-level vision tasks: Analysis and implications.

The study of visual illusions has proven to be a very useful approach in vision science. In this work we start by showing that, while convolutional neural networks (CNNs) trained for low-level visual tasks in natural images may be deceived by brightness and color illusions, some network illusions can be inconsistent with the perception of humans. Next, we analyze where these similarities and differences may come from. On one hand, the proposed linear eigenanalysis explains the overall similarities: in simple CNNs trained for tasks like denoising or deblurring, the linear version of the network has center-surround receptive fields, and global transfer functions are very similar to the human achromatic and chromatic contrast sensitivity functions in human-like opponent color spaces. These similarities are consistent with the long-standing hypothesis that considers low-level visual illusions as a by-product of the optimization to natural environments. Specifically, here human-like features emerge from error minimization. On the other hand, the observed differences must be due to the behavior of the human visual system not explained by the linear approximation. However, our study also shows that more 'flexible' network architectures, with more layers and a higher degree of nonlinearity, may actually have a worse capability of reproducing visual illusions. This implies, in line with other works in the vision science literature, a word of caution on using CNNs to study human vision: on top of the intrinsic limitations of the L + NL formulation of artificial networks to model vision, the nonlinear behavior of flexible architectures may easily be markedly different from that of the visual system.

Derivatives and inverse of cascaded linear+nonlinear neural models.

In vision science, cascades of Linear+Nonlinear transforms are very successful in modeling a number of perceptual experiences. However, the conventional literature is usually too focused on only describing the forward input-output transform. Instead, in this work we present the mathematics of such cascades beyond the forward transform, namely the Jacobian matrices and the inverse. The fundamental reason for this analytical treatment is that it offers useful analytical insight into the psychophysics, the physiology, and the function of the visual system. For instance, we show how the trends of the sensitivity (volume of the discrimination regions) and the adaptation of the receptive fields can be identified in the expression of the Jacobian w.r.t. the stimulus. This matrix also tells us which regions of the stimulus space are encoded more efficiently in multi-information terms. The Jacobian w.r.t. the parameters shows which aspects of the model have bigger impact in the response, and hence their relative relevance. The analytic inverse implies conditions for the response and model parameters to ensure appropriate decoding. From the experimental and applied perspective, (a) the Jacobian w.r.t. the stimulus is necessary in new experimental methods based on the synthesis of visual stimuli with interesting geometrical properties, (b) the Jacobian matrices w.r.t. the parameters are convenient to learn the model from classical experiments or alternative goal optimization, and (c) the inverse is a promising model-based alternative to blind machine-learning methods for neural decoding that do not include meaningful biological information. The theory is checked by building and testing a vision model that actually follows a modular Linear+Nonlinear program. Our illustrative derivable and invertible model consists of a cascade of modules that account for brightness, contrast, energy masking, and wavelet masking. To stress the generality of this modular setting we show examples where some of the canonical Divisive Normalization modules are substituted by equivalent modules such as the Wilson-Cowan interaction model (at the V1 cortex) or a tone-mapping model (at the retina).

Strategies to improve first attempt success at intubation in critically ill patients.

Tracheal intubation in critically ill patients is a high-risk procedure. The risk of complications increases with repeated or prolonged attempts, making expedient first attempt success the goal for airway management in these patients. Patient-related factors often make visualization of the airway and placement of the tracheal tube difficult. Physiologic derangements reduce the patient's tolerance for repeated or prolonged attempts at laryngoscopy and, as a result, hypoxaemia and haemodynamic deterioration are common complications. Operator-related factors such as experience, device selection, and pharmacologic choices affect the odds of a successful intubation on the first attempt. This review will discuss the 'difficult airway' in critically ill patients and highlight recent advances in airway management that have been shown to improve first attempt success and decrease adverse events associated with the intubation of critically ill patients.

Sildenafil for the Treatment of Pulmonary Arterial Hypertension in Infants with Bronchopulmonary Dysplasia.

Sildenafil, a phosphodiesterase-5 inhibitor, is a controversial treatment option for pulmonary arterial hypertension (PAH), a significant complication of bronchopulmonary dysplasia (BPD). The objective of this study was to evaluate the use of sildenafil in infants with PAH secondary to BPD. This was a retrospective review of medical records of all premature infants with PAH associated with BPD treated with sildenafil between January 2009 and May 2013 in a level 3 neonatal intensive care unit. The primary outcomes were clinical response (20 % decreases in respiratory support score or oxygen requirements) and echocardiographic response (20 % decrease in tricuspid regurgitation gradient or change of at least 1° of septal flattening). Twenty-three infants were included in the study. Significant echocardiographic and clinical responses were, respectively, observed in 71 and 35 % of cases. Most clinical responses were observed in the first 48 h of treatment, and the median time to an echocardiographic response was of 19 days. The median dose of sildenafil used was 4.4 mg/kg/day, with a median time to reach the maximum dose of 9 days. Transient hypotension was the primary reported side effect, and it was observed in 44 % of our study population. Sildenafil treatment in patients with PAH secondary to BPD was associated with an echocardiographic improvement in the majority of patients, whereas clinical improvement was observed in a minority of patients. Many infants presented with transient hypotension during the course of the treatment. Further prospective studies are required to better assess safety and efficacy of this treatment in this population.

EAACI Position Paper on assessment of cough in the workplace.

Cough is a nonspecific and relatively common symptom that can present difficulties in diagnosis and management, particularly when it is reported to be associated with the workplace. The present consensus document, prepared by a taskforce of the Interest Group on Occupational Allergy of the European Academy of Allergy and Clinical Immunology by means of a nonsystematic review of the current literature, is intended to provide a definition and classification of work-related chronic cough (WRCC) to assist the daily practice of physicians facing with this symptom. The review demonstrates that several upper and lower airway work-related diseases may present with chronic cough; hence, the possible link with the workplace should always be considered. Due to the broad spectrum of underlying diseases, a multidisciplinary approach is necessary to achieve a definite diagnosis. Nevertheless, more epidemiological studies are necessary to estimate the real prevalence and risk factors for WRCC, the role of exposure to environmental and occupational sensitizers and irritants in its pathogenesis and the interaction with both upper and lower airways. Finally, the best management option should be evaluated in order to achieve the best outcome without adverse social and financial consequences for the worker.

Distinct temporal patterns of immediate asthmatic reactions due to high- and low-molecular-weight agents.

BACKGROUND: Exposure to occupational agents can cause immediate asthmatic reactions. OBJECTIVE: It can be hypothesized that the pattern of immediate reactions is different for high (HMW)- and low-molecular-weight (LMW) agents. To test this, we studied the temporal features of reactions in workers who underwent specific inhalation challenges for possible occupational asthma. METHODS: We examined 467 immediate reactions due to HMW (n = 248, 53%) and LWW (n = 219, 47%) agents in regards to timing of the maximum reaction and recovery. RESULTS: The median duration of exposure to elicit significant immediate reactions was comparable for HMW and LMW agents (15 min). The median maximum fall in FEV (1) occurred after 20 min for LMW by comparison with 10 min for HMW agents (P < 0.001). The median timing of recovery of FEV (1) to 10% baseline was shorter for HMW (60 min) than for LMW (90 min) agents (P < 0.01), and significantly more subjects recovered to 10% baseline (89.5%) for HMW than for LMW agents (72.6%) (P < 0.001). Confounding variables such as age, atopy, baseline airway calibre and the maximum fall in FEV (1) at the time of the immediate reaction did not alter the significant effect of the nature of the agent per se. Immediate reactions were followed by a late asthmatic reaction more often in the case of LMW (37.3%) than HMW (26.2%) agents (P < 0.05). Significant changes in non-specific bronchial responsiveness were significantly (P = 0.02) more frequent after reactions to LMW (31.9%) than to HMW (21.4%) agents. We found similar trends by comparing reactions to flour (n = 113), the principal cause of reactions to HMW agents, and diisocyanates (n = 111), the principal LMW agent. CONCLUSIONS AND CLINICAL RELEVANCE: This study shows distinct patterns for immediate reactions due to occupational agents. These results can provide useful guidelines for performing specific inhalation challenges and improve the safety of the procedure.

Systematic review: the relationship between interstitial lung diseases and gastro-oesophageal reflux disease.

BACKGROUND A potential relationship has been suggested between gastro-oesophageal reflux disease (GERD) and interstitial lung diseases (ILDs). AIM To evaluate whether there is a causal relationship between GERD and different ILDs. METHODS We conducted a systematic search of literature published between 1980 and 2010. After a review by two independent authors, each study was assigned an evidence-based rating according to a standard scoring system. RESULTS We identified 319 publications and 22 of them met the entry criteria. Of those, the relationship between GERD and idiopathic pulmonary fibrosis (IPF) was investigated in 14 articles, pulmonary involvement in systemic sclerosis (SSc) in six articles and pulmonary involvement in mixed connective tissue disease (MCTD) in two articles. We found the prevalence of GERD and/or oesophageal dysmotility to be higher in patients with different types of ILD as compared with those without ILD [Evidence B]. Among patients with IPF, 67-76% demonstrated abnormal oesophageal acid exposure off PPI treatment. No relationship was demonstrated between severity of GERD and severity of IPF [Evidence B]. Data are scant on outcomes of antireflux treatment in patients with IPF. There is a correlation between the severity of ILD and the degree of oesophageal motor impairment in patients with SSc and MCTD [Evidence B]. CONCLUSIONS Based on the currently available data, a causal relationship between GERD and idiopathic pulmonary fibrosis cannot be established. There is scant evidence about antireflux therapy in idiopathic pulmonary fibrosis patients. There may be an association between lung and oesophageal involvement in systemic sclerosis and mixed connective tissue disease, but a causal relationship cannot be established.

Association of bronchial reactivity to occupational agents with methacholine reactivity, sputum cells and immunoglobulin E-mediated reactivity.

BACKGROUND: Bronchial responsiveness and IgE-mediated reactivity are associated with specific bronchial reactivity to allergens. OBJECTIVE: Our aim was to examine whether airway inflammation also plays a role. METHODS: Retrospective analysis of all subjects who underwent specific inhalation challenges in the investigation of occupational asthma (OA) since 2000. Responsiveness to methacholine (PC(20) ) and levels of eosinophils and neutrophils in induced sputum on the control day were associated with the presence of OA (positive-specific inhalation challenge). In a sample of subjects exposed to wheat flour, we also examined the role of specific IgE- mediated reactivity (skin reactivity, specific IgE). RESULTS: PC(20) level was significantly more often normal in subjects with OA (35 of 129, 27% instances) by comparison with non-OA (15 of 189, 8% instances), but the positive predictive value of responsiveness to methacholine for OA was low (35%). Coupling information on the level of eosinophils to responsiveness to methacholine increased positive predictive values for OA from 39% to 69% depending on the thresholds used. The best balance of positive (69%) and negative (60%) predictive values was obtained in the case of normal PC(20) and eosinophils ≥3%. In a multivariate analysis carried out in 34 subjects exposed to wheat flour, responsiveness to methacholine, sputum eosinophils, skin weal size and levels of specific IgE were all significantly associated with OA to wheat flour. CONCLUSION AND CLINICAL RELEVANCE: Information on the level of sputum eosinophils in addition to PC(20) provides a better association with OA vs. non-OA when PC(20) is normal. Levels of sputum eosinophils in addition to PC(20) and IgE-mediated reactivity increase the likelihood of OA due to wheat flour.

[Steps aimed at upgrading a pharmaceutical care sector: the case of neonatology]. / Démarche pour la mise à niveau d'un secteur de soins pharmaceutiques : le cas de la néonatologie.

BACKGROUND: While the concept of clinical pharmacy was developed in the 1960s, clinical outpatient and inpatient programs are characterized by their great variety and disparity when it comes to the presence of pharmacists in healthcare sectors. OBJECTIVES: This article aims to describe a method in which pharmaceutical care sectors in healthcare facilities can be upgraded. METHODS: This is a descriptive study supporting the upgrade of pharmaceutical care practiced in the neonatology sector of a 500-bed mother-child university hospital center, the centre hospitalier universitaire Sainte-Justine (CHUSJ). The CHUSJ's Pharmacy Department employs more than 70 healthcare professionals. The study involved the following upgrading steps: (1) a review of the literature, (2) a description of the profile of the sector and (3) a description of the upgrading of pharmacist practice in neonatology. RESULTS: A total of 121 articles were compiled, 16 of which were selected to evaluate the impact and 54 a description of the pharmacist's role in neonatology. The authors did not identify any particular pharmaceutical activity based on very good quality data (A). However, six of them were based on good quality data (B) and eight lacked adequate proof (C, D) in relation to the practice of neonatology. Nevertheless, a number of other authors described the development of the pharmacist's clinical role in neonatology. This study described the sector profile and upgrading of pharmaceutical practice that resulted from the literature review and a subsequent discussion among pharmacists. CONCLUSION: There are few data on the impact of pharmacists in neonatology. This descriptive study proposes a number of steps aimed at upgrading pharmaceutical care within a Quebec university hospital center.

Factors influencing duration of exposure with symptoms and costs of occupational asthma.

The most important factor for the prognosis of occupational asthma is the length of exposure with symptoms prior to removal from exposure. We wanted to identify factors, including socioeconomic status, that can influence the delay in submitting a claim to a medicolegal agency after the onset of asthmatic symptoms, and to confirm that this delay is associated with worse respiratory prognosis and higher direct costs. This is a cross-sectional study of subjects who claimed compensation for occupational asthma at the Workers' Compensation Board of Quebec, Canada. Data were collected at re-evaluation ∼2.5 yrs after diagnosis. Information on the number of years with symptoms and removal from exposure was obtained from the medicolegal file. 60 subjects were included in the study. Being older, having a revenue of >30,000 Canadian dollars and having occupational asthma due to high molecular weight agents were all positively associated with the number of years of exposure with symptoms before removal from exposure. Subjects with persistent airway hyperresponsiveness at follow-up had a higher number of years with symptoms. Experiencing symptoms in the workplace for <1 yr generated lower direct costs. These findings might help in surveillance programmes that could be preferentially targeted for these subgroups of workers.

Matrix metalloproteinases, IL-8 and glutathione in the prognosis of workers exposed to chlorine.

BACKGROUND: Workers exposed to chlorine may be at risk of deterioration in FEV1. METHODS: A prospective study of 72 workers examined over a 5.8 +/- 1.9 year period. A sample of induced sputum for cells and mediators was obtained in 69 subjects at baseline (Vb) and in 36 both at Vb and at follow-up (Vf). RESULTS: Sixty-four workers (89%) experienced at least one accidental inhalation of chlorine in the interval. The mean decrease in FEV1 was 30 ml/year and thus was within normal limits. Among the analysed remodelling markers, the level of the MMP-9-TIMP-1 complex, but not of free MMP-9 and TIMP-1, significantly diminished from Vb to Vf. We found significant correlations between neutrophils, IL-8, MMP-9 and MMP9-TIMP-1 complex at Vb and Vf. While levels of total glutathione, IL-8, MMP9, TIMP-1 and MMP9-TIMP-1 complex were highly correlated with each other at Vb, this was inconstant at Vf. Levels of MMP9-TIMP1 complex and of TIMP1 at Vf were significantly lower in workers reporting chlorine puffs with mild acute respiratory symptoms between visits compared to those who had no, or asymptomatic inhalations (P = 0.03 and 0.02, respectively). The fall in FEV1 from Vb to Vf was significantly correlated with levels of glutathione at Vb. Cough between visits was associated with a decrease in FEV1 (P = 0.06). CONCLUSION: Although no accelerated loss in FEV1 was documented in these workers exposed to chlorine, subjects with a greater fall in FEV1 were more likely to report cough and have higher levels of total glutathione at Vb.

Control and severity of asthma during pregnancy are associated with asthma incidence in offspring: two-stage case-control study.

The extent to which childhood asthma incidence is influenced by asthma control and severity during pregnancy is unknown. We have studied this association during the child's first 10 yrs of life. A two-stage, case-control study, nested in a cohort of 8,226 children of asthmatic mothers, was conducted using three interlinked databases of Quebec, Canada, and mailed questionnaires. A total of 2,681 asthmatic children and 30,318 age-matched controls were selected (< or =20 controls.case(-1); stage 1), and 3,254 selected mothers were mailed questionnaires to obtain additional information (stage 2). Asthma control and severity was defined using validated indexes and childhood asthma incidence based on at least one asthma-related diagnosis and prescription received within 2 yrs. A total of 44 confounders were considered. Compared with children of mild controlled asthmatic mothers, children whose mothers had moderate-to-severe uncontrolled asthma during pregnancy had an increased risk of asthma (adjusted OR 1.27, 95% CI 1.06-1.52). No increased risk was observed for children of mild uncontrolled and moderate-to-severe controlled mothers. Based on one of the largest studies of children of asthmatic mothers, a significant increase in asthma risk was demonstrated among children whose mothers had poor control and increased severity of asthma during pregnancy, indicating that this element should be added to the expanding list of determinants of childhood asthma. As it constitutes a risk factor where pregnant asthmatic females can intervene, it is of great importance for physicians to optimally treat asthmatic females during pregnancy and to encourage females to be adherent to the prescribed asthma medications.

Malt can cause both occupational asthma and allergic alveolitis.

Specific inhalation challenge can help differentiate occupational asthma from allergic alveolitis caused by malt.

Occupational rhinitis in workers investigated for occupational asthma.

BACKGROUND: The links between asthma and rhinitis are now referred to as united airways disease (UAD). Current evidence shows that the UAD model seems to be applicable to occupational rhinitis (OR) and occupational asthma (OA). A study was undertaken to objectively assess, in the context of specific inhalation challenge (SIC) testing, the concomitance of bronchial and nasal reaction in the investigation of OR and OA. METHODS: 43 subjects with a history of work-related asthma symptoms underwent SIC for confirmation of OA and investigation of OR. Changes in bronchial calibre were measured by spirometry and nasal patency and airway inflammation were assessed by acoustic rhinometry and nasal lavage. RESULTS: A positive nasal challenge was observed in 25 SIC tests and a positive bronchial challenge was observed in 17 SIC tests. A concomitant positive nasal and bronchial challenge was observed in 13 instances. This association was significant (risk ratio = 1.7; 95% CI 1.0 to 2.4; p = 0.04) and more frequent in subjects challenged with high molecular weight agents (n = 11/22) than with low molecular weight agents (n = 2/21). In subjects with a positive nasal challenge, nasal lavage showed a significant increase in eosinophils 30 min after exposure which correlated with changes in nasal patency. CONCLUSION: The results of this study provide objective evidence to support the concept of UAD using OR and OA as a model to demonstrate a significant concomitant physiological reaction of the nose and lungs after challenge. This study shows that OR can be assessed by objective means; it often coexists with OA but can be present without OA.

Risks for the development of outcomes related to occupational allergies: an application of the asthma-specific job exposure matrix compared with self-reports and investigator scores on job-training-related exposure.

BACKGROUND AND AIM: Risks for development of occupational sensitisation, bronchial hyper-responsiveness, rhinoconjunctival and chest symptoms at work associated with continued exposure to high molecular weight (HMW) allergens were estimated with three exposure assessment methods. METHODS: A Cox regression analysis with adjustment for atopy and smoking habit was carried out in 408 apprentices in animal health technology, pastry making, and dental hygiene technology with an 8-year follow-up after training. The risk of continued exposure after training, estimated by the asthma-specific job exposure matrix (JEM), was compared with self-reports and investigator scores on job-training-related exposure. Associations between outcomes and work duration in job(s) related to training were also evaluated. RESULTS: Exposure to animal-derived HMW allergens, subsequent to the apprenticeship period, as estimated by the JEM, was associated with a significantly increased risk for occupational sensitisation (hazard ratio (HR) 6.4; 95% CI 2.3 to 18.2) and rhinoconjunctival symptoms at work (HR 2.6; 95% CI 1.1 to 6.2). Exposure to low molecular weight (LMW) agents significantly increased the risk of developing bronchial hyper-responsiveness (HR 2.3; 95% CI 1.1 to 5.4). Exposure verification appeared to be important to optimise the sensitivity and the specificity, as well as HRs produced by the JEM. Self-reports and investigator scores also indicated that further exposure to HMW allergens increased the risk of developing occupational allergies. The agreement between self-reports, investigator scores, and the JEM were moderate to good. There was no significant association between respiratory outcomes and work duration in jobs related to training. CONCLUSION: The asthma-specific JEM could estimate the risk of various outcomes of occupational allergies associated with exposure to HMW and LMW allergens, but it is relatively labour intensive. Exposure verification is an important integrated step in the JEM that optimised the performance of the matrix.

Which tools best predict the incidence of work-related sensitisation and symptoms.

BACKGROUND/AIM: This study used information from the questionnaire alone or in conjunction with clinical tests, such as skin-prick testing (SPT) and bronchial responsiveness (BR) testing at entry, to develop models for estimating the probability of the occurrence of specific IgE-sensitisation to and respiratory symptoms in contact with laboratory animal (LA) allergens after 32 months' training in an animal health technology programme. METHODS: Four multivariable logistic regression models were developed for each endpoint, consisting of: (1) questionnaire; (2) questionnaire and SPT; (3) questionnaire and BR testing; and (4) questionnaire, SPT and BR testing. The prognostic models were derived from a cohort of Canadian animal health technology apprentices. The models' internal validity and diagnostic accuracy were evaluated and compared. RESULTS: Symptoms indicative of asthma and allergic symptoms at baseline composed the final questionnaire model for the occurrence of occupational sensitisation and symptoms. Both questionnaire models showed a good discrimination (area under the receiver operating characteristics curve were 0.73 and 0.78, respectively) and calibration (Hosmer-Lemeshow test p value >0.10). Addition of SPT and/or BR testing increased the specificity of the questionnaire model for LA sensitisation, but not for symptoms at work. To facilitate their application in practice, the final questionnaire models were converted to easy-to-use scoring system. CONCLUSIONS: Questionnaire is an easy tool that can give accurate prediction of the incidence of occupational sensitisation and symptoms.