Exploration of associations between occupational exposures and current adult eczema

OBJECTIVES

There is a scarcity of evidence on occupational exposures that may increase eczema in adults. We aimed to investigate potential associations between occupational exposures and eczema in middle-aged adults.

METHODS

A lifetime work history calendar was collected from the Tasmanian Longitudinal Health Study participants when they were at age 53. Their work history was collated with the occupational asthma-specific job exposure matrix to define ever-exposure and cumulative exposure unit-years since no eczema job exposure matrix is available. Eczema was determined using the report of flexural rash that was coming and going for at least 6 months in the last 12 months. Skin prick tests were used to further subgroup eczema and atopic eczema (AE) or non-AE (NAE). Logistic and multinomial regression models were used to investigate the associations.

RESULTS

Eczema prevalence was 9.1%. Current occupational exposure to animals (adjusted OR, aOR=3.06 (95% CI 1.43 to 6.58)), storage mites (aOR=2.96 (95% CI 1.38 to 6.34)) and endotoxin (aOR=1.95 (95% CI 1.04 to 3.64)) were associated with increased risk of current eczema. Furthermore, increased odds of NAE were associated with current exposure to animals (aOR=5.60 (95% CI 1.45 to 21.7)) and storage mites (aOR=5.63 (95% CI 1.45 to 21.9)). Current exposures to isocyanates (aOR=5.27 (95% CI 1.17 to 23.7)) and acrylates (aOR=8.41 (95% CI 1.60 to 44.3)) were associated with AE. There was no evidence of associations between cumulative exposures and eczema prevalence. Cumulative exposure to metalworking fluids (aOR=1.10 (95% CI 1.01 to 1.22)) was associated with NAE and acrylates (aOR=1.24 (95% CI 1.04 to 1.46)) with AE.

CONCLUSIONS

In this exploratory assessment, multiple occupational exposures were associated with current eczema in middle-aged adults. Raising awareness and limiting these exposures during an individual's productive working life will likely have various health benefits, including reducing eczema prevalence.

Undiagnosed and 'overdiagnosed' COPD using postbronchodilator spirometry in primary healthcare settings: a systematic review and meta-analysis

BACKGROUND

Despite chronic obstructive pulmonary disease (COPD) being a major global cause of mortality and hospitalisation, it is often undiagnosed or inaccurately diagnosed in clinical settings.

OBJECTIVE

To systematically synthesise all peer-reviewed papers from primary healthcare settings that have reported data on: (1) undiagnosed COPD, that is, patients with respiratory symptoms and postbronchodilator airflow obstruction consistent with COPD, without a formal clinician's diagnosis of COPD either documented in health records or reported by patients and (2) 'overdiagnosed COPD', that is, clinician's diagnosis without postbronchodilator airflow obstruction.

METHODS

Studies investigating these diagnostic metrics in patients from primary healthcare clinics (according to predefined inclusion/exclusion criteria) were sourced from Medline and Embase and assessed for bias (Johanna Briggs Institute tools for prevalence studies and case series). Meta-analyses of studies of adequate sample size used random effect modelling stratified by risk factor categories.

RESULTS

Of 26 eligible articles, 21 cross-sectional studies investigated 3959 cases of spirometry-defined COPD (with or without symptoms), and 5 peer-reviewed COPD case series investigated 7381 patients. The prevalence of spirometry-confirmed COPD without a diagnosis documented in their health records was 14%-26% in studies of symptomatic smokers (N=3). 1 in 4 patients taking inhaled therapies (25% (95% CI 22% to 28%), N=2) and 1 in 6 smokers irrespective of symptoms (16% (95% CI 14% to 18%), N=6) fulfilled diagnostic spirometry criteria but did not report receiving a COPD-related diagnosis. In an adequately powered series of COPD cases documented in primary healthcare records (N=4), only between 50% and 75% of subjects had any airflow obstruction on postbronchodilator spirometry performed by study researchers, therefore, COPD was clinically 'overdiagnosed' in 25%-50% of subjects.

DISCUSSION

Although data were heterogeneous and of modest quality, undiagnosed COPD was common in primary healthcare, especially for symptomatic smokers and patients treated with inhaled therapies. In contrast, frequent COPD 'overdiagnosis' may represent treatment of asthma/reversible component or another medical diagnosis.

PROSPERO REGISTRATION NUMBER

CRD42022295832.

Small for gestational age is associated with reduced lung function in middle age: A prospective study from first to fifth decade of life

BACKGROUND AND OBJECTIVE

The association between birth weight, particularly relative to gestational age, and adult lung function is uncertain. We investigated the associations between birth weight relative to gestational age and measures of lung function in middle age, and mediation of these associations by adult height.

METHODS

Participants in the Tasmanian Longitudinal Health Study who had both known birth weight and lung function assessment at age 45 years were included (n = 849). Linear regression models were fitted to investigate the association between small for gestational age and birth weight with post-bronchodilator lung function measures (forced expiratory volume in 1 second [FEV1 ], forced vital capacity [FVC], FEV1 /FVC, diffusing capacity for carbon monoxide [DL co], residual volume [RV] and total lung capacity [TLC]), adjusting for potential confounders. The contribution of adult height as a mediator of these associations was investigated.

RESULTS

Compared with infants born with normal weight for gestational age, those born small for gestational age had reduced FEV1 (coefficient: -191 ml [95%CI: -296, -87]), FVC (-205 ml [-330, -81]), TLC (-292 ml [-492, -92]), RV (-126 ml [-253, 0]) and DL co (-0.42 mmol/min/kPa [-0.79, -0.041]) at age 45 years. However, they had comparable FEV1 /FVC. For every 1 kg increase in birth weight, lung function indices increased by an average of 117 ml (95%CI: 40, 196) for FEV1 , 124 ml (30, 218) for FVC, 215 ml (66, 365) for TLC and 0.36 mmol/min/kPa (0.11, 0.62) for DL co, independent of gestational age, but again not for FEV1 /FVC. These associations were significantly mediated by adult height (56%-90%).

CONCLUSION

Small for gestational age was associated with reduced lung function that is likely due to smaller lungs with little evidence of any specific parenchymal impairment.

Longitudinal Sleep Study in Pregnancy: Cohort Profile and Prevalence and Risk Factors for Sleep Symptoms in the First Trimester

Sleep disorders could influence pregnancy outcomes but evidence for longitudinal associations is scarce. We established a prospective cohort of women to determine incident sleep issues and their adverse health outcomes during pregnancy and beyond, and present here the baseline cohort profile. Antenatal women in gestational weeks 8-12 were recruited (n = 535) and followed-up in each trimester and at 5-6 weeks postpartum (no attrition). Sleep symptoms and disorders were measured using STOP-Bang and Berlin questionnaires and Pittsburgh Sleep Quality Index. Incident health outcomes were extracted from clinical records. At the time of recruitment, habitual snoring was present in 13.8% of participants; "excessive sleepiness during the day" (EDS) in 42.8%; short (<7 h) sleep duration in 46.4%; "having trouble sleeping" in 15.3%; and "poor subjective sleep quality" in 8.6%. Habitual snoring was strongly associated with irregular menstrual periods for one year preceding pregnancy (p = 0.014) and higher BMI (p < 0.001). Higher age was associated with less "trouble sleeping" (OR 0.9, p = 0.033) and longer sleep duration was associated with better "subjective sleep quality" (OR 0.8, p = 0.005). Sleep issues were highly prevalent at baseline and associated with age, irregular menstruation, and obesity. This cohort will provide a robust platform to investigate incident sleep disorders during pregnancy and their effects on adverse pregnancy outcomes and long-term health of women and their offspring.

Environmental life cycle assessment of production of the high intensity sweetener steviol glycosides from Stevia rebaudiana leaf grown in Europe: The SWEET project

PURPOSE

There is an increasing interest in the use of non-nutritive sweeteners to replace added sugar in food and beverage products for reasons of improving consumer health. Much work has been done to understand safety of sweeteners, but very little on sustainability. To address that gap, this study presents the results of a life cycle assessment (LCA) of production of rebaudioside A 60%, 95% pure (RA60) steviol glycoside mix from Stevia rebaudiana leaf grown in Europe.

METHODS

An attributional cradle-to-factory-gate life cycle assessment was conducted on growing of stevia leaves and extraction of steviol glycosides in Europe. Primary data were used from a case study supply chain. Results are reported in impact categories from the ReCiPe 2016 (H) method, with focus given to global warming potential, freshwater eutrophication, water consumption, and land use. Impacts are expressed both in terms of production mass and sweetness equivalence, a common metric for understanding high intensity sweetener potency. Sweetness equivalence of RA60 is typically 200 to 300 times that of sugar. Comparison of environmental impact is made to sugar (sucrose) produced from both cane and beets. The research is part of the EU project SWEET (sweeteners and sweetness enhancers: impact on health, obesity, safety, and sustainability).

RESULTS AND DISCUSSION

Global warming potential for production of RA60 was found to be 20.25 kgCO₂-eq/kg_RA60 on a mass basis and 0.081 kgCO₂-eq/kg_SE on a sweetness equivalence basis. Field production of stevia leaves was found to be the main source of impact for most impact categories, and for all four focus categories. Extraction of the RA60 was the main source of impact for the others. Leaf processing and seedling propagation were minor contributors to life cycle impact. Removal of international transport from the supply chain reduced global warming potential by 18.8%. Compared with sugar on a sweetness equivalence basis, RA60 has approximately 5.7% to 10.2% the impact for global warming potential, 5.6% to 7.2% the impact for land use, and is lower across most other impact categories.

CONCLUSION

This is the first LCA of steviol glycoside mix RA60 produced from leaf in Europe. The results indicate that RA60 can be used to reduce environmental impact of providing a sweet taste by replacing sugar across all impact categories. However, it is important to note that specific formulations in which RA60 is used will have a bearing on the final environmental impact of any food or beverage products. For solid foods, this requires further research.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11367-022-02127-9.

Student Veterinarian Perceptions of Community-Based Primary Care Veterinary Clinics in Indigenous Communities in Southern Ontario, Canada

Community-based primary care veterinary clinics represent an opportunity to benefit multiple populations. Student veterinarians are afforded the opportunity to build technical and non-technical professional skills, while underserved communities are provided with access to companion animal care. The Ontario Veterinary College (OVC), as with many other veterinary colleges across Canada and the United States, has hosted community-based primary care veterinary clinics, including in local Indigenous communities. As these clinics continue and grow, it is critical to evaluate their operation to ensure that they align with community goals and values, adequately support student learning, and do not perpetuate racism and implicit bias. The objective of this study was to explore the perceptions of student veterinarians who had volunteered at community-based primary care veterinary clinics in First Nations communities in southern Ontario, Canada. We used an online survey that consisted of multiple choice and short answer questions focused on motivating factors for involvement, supports available before and during the clinics, exposure to Indigenous cultures, and the challenges and rewards associated with volunteering. Forty-one student veterinarians from OVC completed the survey in January 2020. Most students were motivated to volunteer to make a positive difference in the lives of people and animals and improve their clinical skills. In general, respondents felt adequately prepared for and supported during their experiences but did recommend additional pre-departure instructions on roles and responsibilities. Participants were ambivalent as to whether they had learned about Indigenous culture, with several strongly recommending more cultural sensitivity training. Most students found their experiences rewarding because of the gratitude expressed by clients and the feeling that they had made a difference. We reflect on the potential benefits and challenges of community-based primary care veterinary clinics in light of student responses.

De la mort psychique à l’envie de vivre : l’ambivalence quand il y a encore des choses à vivre, à l’envie de vivre quand l’échéance est là…

La prise en charge du cancer et sa perspective potentiellement palliative modifient profondément l’état psychique du patient, dans son rapport au temps, son adaptation, ses défenses et dans son rapport à la réalité de la mort et ses bouleversements. Dans cette période de turbulence, il n’est pas rare que le patient, les proches et les soignants ne se retrouvent pas sur le même temps d’élaboration autour de la mort à venir et des changements physiques et/ou psychiques qui accompagnent cette période de vie. La situation de notre patiente est l’illustration des fluctuations de la vie psychique et des mécanismes de défense patient/soignant/proche vers l’acheminement de la fin de vie et de la mort.

Protein levels, air pollution and vitamin D deficiency: links with allergy

This study provides novel insights into mechanisms of traffic-related air pollution-induced allergy by down-regulation via complement regulators (CFI, PROS1 and PLG) and its interaction with vitamin D deficiency via the complement inhibitor PLG https://bit.ly/3x0jYOw.

1388Risk factors for chronic cough in adults: A systematic review and meta-analysis

Background

Despite the challenges of diagnosing and managing adult patients with chronic cough, a systematic synthesis of evidence on aetiological risk factor is lacking.

Methods

We systematically searched PUBMED and EMBASE to synthesize the current evidence for longitudinal associations between various risk factors and chronic cough in the general adult population, following the meta-analysis of observation studies in epidemiology (MOOSE) guidelines. The Newcastle-Ottawa scale was used to assess the quality of the included studies. Fixed-effect meta-analysis was conducted where appropriate.

Results

Of 26 eligible articles, 16 domains of risk factors were assessed. There was consistent evidence that asthma (pooled adjusted OR (aOR) = 3.01; 95%CI: 2.33-3.70; I2=0%, number of articles (N)=3) and low education levels/socioeconomic status (SES) (pooled aOR=1.46; 95%CI: 1.20-1.72; I2=0%; N = 3) were associated with an increased risk of chronic cough after adjusting for smoking and other confounders. While continuous smoking was associated chronic cough (aOR =1.81; 95%CI: 1.36,2.26; I2=57%; N = 3), there was too little evidence to draw conclusions for occupational exposures, outdoor air pollution, early-life exposures, diet, snoring and other chronic conditions.

Conclusions

Asthma, persistent smoking and lower education/SES were associated with increased risk of chronic cough. Longitudinal associations between other factors frequently mentioned empirically need further investigation.

Key messages

Our systematic review found asthma, smoking and lower education to be associated with adult chronic cough. More longitudinal studies are needed to understand other potential risk factors for adult chronic cough.

550Short-term exposure to grass pollen is associated with lower lung function and increased airway inflammation

Background

The association between grass pollen exposure and lung function changes and airway inflammation is limited. We investigated these associations in a community-based sample, and whether any such associations were modified by current asthma, current hay fever, pollen sensitization and age.

Methods

Cross-sectional analyses of data from the Melbourne Atopy Cohort Study (MACS) participants (n = 936). Lung function was assessed using spirometry. Airway inflammation was assessed by fractional exhaled nitric oxide (FeNO), and exhaled breath condensate pH and nitrogen oxides (NOx). Daily pollen counts were collected using a volumetric spore trap. The associations were examined by linear regression.

Results

Higher ambient levels of grass pollen 2 days before (lag 2) were associated with lower mid-forced expiratory flow (FEF25-75%) and FEV1/FVC ratio (Coef. [95% CI] = -119 [-226, -11] mL/s and -1.0 [-3.0, -0.03] %, respectively) and also 3 days before (lag 3). Increased levels of grass pollen a day before (lag 1) was associated with increased FeNO (4.35 [-0.1, 8.7] ppb) and also at lag 2. Adverse associations between pollen and multiple outcomes were greater in adults with current asthma, hay fever and pollen sensitization.

Conclusions

Grass pollen exposure was associated with eosinophilic airway inflammation 1-2 days after exposure and airway obstruction 2-3 days after exposure.

Key messages

There is a more delayed effect on lung function compared to airway inflammation. Adults with current asthma, hay fever and grass pollen sensitisation are especially vulnerable.

Snoring and nocturnal reflux: association with lung function decline and respiratory symptoms

Introduction

The study aim was to examine the association of snoring and nocturnal gastro-oesophageal reflux (nGOR) with respiratory symptoms and lung function, and if snoring and/or nGOR associated with a steeper decline in lung function.

Methods

Data from the third visit of the European Community Respiratory Health Survey (ECRHS) was used for cross-sectional analysis. Pre- and post-bronchodilator spirometry was performed, and information on sleep, nGOR and respiratory symptoms was collected (n=5715). Habitual snoring and nGOR were assessed by questionnaire reports. Pre-bronchodilator spirometry from ECRHS I, II and III (20 years follow-up) were used to analyse lung function changes by multivariate regression analysis.

Results

Snoring and nGOR were independently associated with a higher prevalence of wheeze, chest tightness, breathlessness, cough and phlegm. The prevalence of any respiratory symptom was 79% in subjects with both snoring and nGOR versus 56% in those with neither (p<0.001). Subjects with both snoring and nGOR had more frequent exacerbations (adjusted prevalence 32% versus 19% among "no snoring, no nGOR", p=0.003). Snoring but not nGOR was associated with a steeper decline in forced expiratory volume in 1 s over 10 years after adjusting for confounding factors (change in % predicted -5.53, versus -4.58 among "no snoring", p=0.04) and forced vital capacity (change in % predicted -1.94, versus -0.99 among "no snoring", p=0.03).

Conclusions

Adults reporting both habitual snoring and nGOR had more respiratory symptoms and more frequent exacerbations of these symptoms. Habitual snoring was associated with a steeper decline in lung function over time.

Early-life exposure to sibling modifies the relationship between CD14 polymorphisms and allergic sensitization

BACKGROUND

Markers of microbial exposure are thought to be associated with risk of allergic sensitization; however, the associations are inconsistent and may be related to gene-environment interactions.

OBJECTIVE

To examine the relationship between polymorphisms in the CD14 gene and allergic sensitization and whether sibling exposure, as a marker of microbial exposure, modified this relationship.

METHODS

We used data from the Tasmanian Longitudinal Health Study and the Melbourne Atopy Cohort Study. Two CD14 polymorphisms were genotyped. Allergic sensitization was defined by a positive response to a skin prick test. Sibling exposure was measured as cumulative exposure to siblings before age 6 months, 2 and 4 years. Logistic regression and multi-level mixed-effects logistic regression were used to examine the associations. Effect estimates across the cohorts were pooled using random-effects meta-analysis.

RESULTS

CD14 SNPs were not individually associated with allergic sensitization in either cohort. In TAHS, cumulative sibling exposure before age 6 months, 2 and 4 years was each associated with a reduced risk of allergic sensitization at age 45 years. A similar effect was observed in MACS. Meta-analysis across the two cohorts showed consistent evidence of an interaction between cumulative sibling exposure before 6 months and the rs5744455-SNP (P = 0.001) but not with the rs2569190-SNP (P = 0.60). The pooled meta-analysis showed that the odds of sensitization with increasing cumulative exposure to sibling before 6 months of age was 20.9% smaller in those with the rs5744455-C-allele than the T-allele (OR = 0.83 vs 1.05, respectively).

CONCLUSION AND CLINICAL RELEVANCE

Cumulative sibling exposure reduced the risk of sensitization from childhood to middle age in genetically susceptible individuals.

Pre-natal and post-natal exposure to pet ownership and lung function in children: The Seven Northeastern Cities Study

To evaluate the association between pre-natal and post-natal exposure to pet ownership and lung function in children, a cross-sectional study named Seven Northeastern Cities (SNEC) study was conducted. In this study, children's lung function including the forced expiratory volume in 1 second (FEV₁ ), forced vital capacity (FVC), maximal mid-expiratory flow (MMEF), and peak expiratory flow (PEF) were measured by spirometers, and pet ownership situations were collected by questionnaire. Analyzed by multiple logistic regression and generalized linear modeling, we found that for all subjects, pet exposure in the first 2 years of life was significantly associated with lung function impairment of FVC<85% predicted (adjusted odds ratio [aOR]=1.28; 95% confidence interval [CI]: 1.01, 1.63). For current pet exposure, the increased odds of lung function impairment ranged from 35% (aOR=1.35; 95%CI: 1.12, 1.62) for FVC<85% predicted to 57% (aOR=1.57; 95%CI: 1.29, 1.93) for FEV₁ <85% predicted. The in utero exposure was not related to lung function impairment. Compared with other pets, higher odds were observed among children with dogs. When stratified by gender, girls with current pet exposure were more likely to have lung function impairment than boys. It implies self-reported exposures to pets were negatively associated with lung function among the children under study.

Positive association between short-term ambient air pollution exposure and children blood pressure in China-Result from the Seven Northeast Cities (SNEC) study

The impact of ambient air pollution on health causes concerns in China. However, little is known about the association of short-term air pollution exposure with blood pressure (BP) in children. The goal of present study was to assess the association between short-term air pollution and BP in children from a highly polluted area in China. This study enrolled 9354 children in 24 elementary and middle schools (aged 5-17 years) from the Seven Northeast Cities (SNEC) study, respectively, during the period of 2012-2013. Ambient air pollutants, including particulate matter with an aerodynamic diameter of ≤10 μm (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂) and ozone (O₃) on the days (1-5 days) preceding BP examination were collected from local air monitoring stations. Generalized additive models and two-level regression analyses were used to evaluate the relationship between air pollution and BP after adjusting for other covariates. Results showed that with an interquartile range (IQR) increase in PM₁₀ (50.0 μg/m³) and O₃ (53.0 μg/m³) level during the 5-day mean exposure, positive associations with elevated BP were observed, with an odds ratio of 2.17 (95% CI, 1.61-2.93) for PM₁₀ and 2.77 (95% CI, 1.94-3.95) for O₃. Both systolic BP and diastolic BP levels were positively associated with an IQR increase of four air pollutants at different lag times. Specifically, an IQR increase in the 5-day mean of PM₁₀ and O₃ was associated with elevation of 2.07 mmHg (95% CI, 1.71-2.44) and 3.29 mmHg (95% CI, 2.86-3.72) in systolic BP, respectively. When stratified by sex, positive relationships were observed for elevated BP with NO₂ exposure only in males. This is the first report on the relationship between ambient short-term air pollution exposure and children BP in China. Findings indicate a need to control air pollutants and protect children from heavy air pollution exposure in China.

Association of perfluoroalkyl substances exposure with impaired lung function in children

Previous studies have demonstrated associations between serum levels of perfluoroalkyl substances (PFASs) and asthma or asthma related-biomarkers. However, no studies have reported a possible relationship between PFASs exposure and lung function among children. The objective of the present study is to test the association between PFASs exposure and lung function in children from a high exposure area by using a cross-sectional case-control study, which included 132 asthmatic children and 168 non-asthmatic controls recruited from 2009 to 2010 in the Genetic and Biomarkers study for Childhood Asthma. Structured questionnaires were administered face-to-face. Lung function was measured by spirometry. Linear regression models were used to examine the influence of PFASs on lung function. The results showed that asthmatics in our study had significantly higher serum PFAS concentrations than healthy controls. Logistic regression models showed a positive association between PFASs and asthma, with adjusted odds ratios (ORs) ranging from 0.99 (95% confidence interval [CI]: 0.80-1.21) to 2.76 (95% CI: 1.82-4.17). Linear regression modeling showed serum PFASs levels were significantly negatively associated with three pulmonary function measurements (forced vital capacity: FVC; forced expiratory volume in 1s: FEV₁; forced expiratory flow 25-75%: FEF_25-75) among children with asthma, the adjusted coefficients between lung function and PFASs exposure ranged from -0.055 (95%CI: -0.100 to -0.010) for FVC and perfluorooctane sulfonate (PFOS) to -0.223 (95%CI: -0.400 to -0.045) for FEF_25-75 and perfluorooctanoic acid (PFOA). PFASs were not, however, significantly associated with pulmonary function among children without asthma. In conclusion, this study suggests that serum PFASs are associated with decreased lung function among children with asthma.

The interaction between farming/rural environment and TLR2, TLR4, TLR6 and CD14 genetic polymorphisms in relation to early- and late-onset asthma

Asthma phenotypes based on age-of-onset may be differently influenced by the interaction between variation in toll-like receptor (TLR)/CD14 genes and environmental microbes. We examined the associations between single-nucleotide polymorphisms (SNP) in the TLR/CD14 genes and asthma, and their interaction with proxies of microbial exposure (childhood farm exposure and childhood rural environment). Ten SNPs in four genes (TLR2, TLR4, TLR6, CD14) were genotyped for 1,116 participants from the Tasmanian Longitudinal Health Study (TAHS). Using prospectively collected information, asthma was classified as never, early- (before 13 years) or late-onset (after 13 years). Information on childhood farm exposure/childhood rural environment was collected at baseline. Those with early-onset asthma were more likely to be males, had a family history of allergy and a personal history of childhood atopy. We found significant interaction between TLR6 SNPs and childhood farm exposure. For those with childhood farm exposure, carriers of the TLR6-rs1039559 T-allele (p-interaction = 0.009) and TLR6-rs5743810 C-allele (p-interaction = 0.02) were associated with lower risk of early-onset asthma. We suggest the findings to be interpreted as hypothesis-generating as the interaction effect did not withstand correction for multiple testing. In this large, population-based longitudinal study, we found that the risk of early- and late-onset asthma is differently influenced by the interaction between childhood farming exposure and genetic variations.

Early smoke exposure is associated with asthma and lung function deficits in adolescents

OBJECTIVE

Early life tobacco smoke exposure may influence asthma, lung function and lung function growth into adolescence. We aimed to determine the associations between perinatal smoke exposure and asthma and lung function up to 18 years of age.

METHODS

We prospectively recorded perinatal parental smoking and measured respiratory outcomes at 12 and 18 years in the Melbourne Atopy Cohort Study (MACS), a longitudinal birth cohort. Multiple logistic regression was used to analyse the associations between perinatal smoke exposure and asthma at 12 (n = 370) and 18 years (n = 411). Multiple linear regression was used to investigate the relationship between perinatal smoking and: lung function (12 and 18 years) and lung function growth (between 12 and 18 years).

RESULTS

At 18 years, girls exposed to parental smoking during the perinatal period had increased odds of asthma (OR: 3.45, 95%CI: 1.36, 8.77), reduced pre-bronchodilator Forced expiratory volume in one-second (FEV₁) (-272 ml/s; -438, -107); FEV₁/ forced vital capacity (FVC) (-0.038; -0.065, -0.010); mid expiratory flow (MEF_25-75) (-430 ml/s; -798, -61), and reduced post-bronchodilator FEV₁/FVC (-0.028, -0.053, -0.004). No associations were found for boys (pre-bronchodilator FEV₁ 26ml/s; -202, 255; FEV₁/FVC 0.018; -0.013, 0.049).

CONCLUSIONS

Perinatal smoke may affect risk of asthma, reduce lung function and lung function growth in adolescence. Girls appear to be more susceptible than boys.

The influence of childhood traffic-related air pollution exposure on asthma, allergy and sensitization: a systematic review and a meta-analysis of birth cohort studies

The impact of early childhood traffic-related air pollution (TRAP) exposure on development of asthma and allergies remains unclear. Birth cohort studies are the best available study design to answer this question, but the evidence from such studies has not been synthesized to date. We conducted a systematic review and meta-analyses of published birth cohort studies to understand the association between early childhood TRAP exposure, and subsequent asthma, allergies and sensitization. Increased longitudinal childhood exposure to PM2.5 and black carbon was associated with increasing risk of subsequent asthma in childhood (PM2.5 : OR 1.14, 95%CI 1.00 to 1.30 per 2 μg/m(3) and black carbon: OR 1.20, 95%CI 1.05 to 1.38 per 1 × 10(-5) m(-1) ). Also, early childhood exposure to TRAP was associated with development of asthma across childhood up to 12 years of age. The magnitude of these associations increased with age, and the pattern was prominent for PM2.5 . Increasing exposure to PM2.5 was associated with sensitization to both aero- and food allergens. There was some evidence that TRAP was associated with eczema and hay fever. In summary, exposure to TRAP was related to asthma and allergic diseases. However, the substantial variability across studies warrants long-term birth cohort studies with regular repeated follow-ups to confirm these findings.

Ambient wood smoke, traffic pollution and adult asthma prevalence and severity

BACKGROUND AND OBJECTIVE

The impact of ambient wood smoke and traffic-related air pollution on adult asthma has not been well studied. This paper aims to investigate associations between exposure to ambient wood smoke, traffic-related air pollution and current asthma/asthma severity in middle age, and whether any associations are modified by atopic status.

METHODS

Using data from the Tasmanian Longitudinal Health Study, associations between ambient wood smoke and two indices of traffic-related air pollution (frequency of heavy vehicles near the home and frequency of intense traffic noise) and current asthma/asthma severity were investigated. Unconditional logistic regression to examine current asthma and ordinal logistic regression to examine asthma severity was used.

RESULTS

For asthmatics, both exposure to ambient wood smoke (odds ratio 1.11; 95% confidence interval 1.02-1.20) and being frequently exposed to heavy vehicles (odds ratio 1.80; 95% confidence interval 1.09-2.96) were associated with increased asthma severity. Neither association varied by atopic status.

CONCLUSIONS

In middle-aged adults, ambient wood smoke and traffic pollution were associated with increased asthma severity. These findings suggest that avoiding or limiting exposure to traffic pollution and wood smoke may help to reduce asthma. Future studies to replicate this finding are recommended and should examine specific biological mechanisms for this effect.

Hyperosmotic stress induces cell cycle arrest in retinal pigmented epithelial cells

Osmotic changes occur in many tissues and profoundly influence cell function. Herein, we investigated the effect of hyperosmotic stress on retinal pigmented epithelial (RPE) cells using a microarray approach. Upon 4-h exposure to 100 mM NaCl or 200 mM sucrose, 79 genes were downregulated and 72 upregulated. Three gene ontology categories were significantly modulated: cell proliferation, transcription from RNA polymerase II promoter and response to abiotic stimulus. Fluorescent-activated cell sorting analysis further demonstrated that owing to hyperosmotic stimulation for 24 h, cell count and cell proliferation, as well as the percentage of cells in G0/G1 and S phases were significantly decreased, whereas the percentage of cells in G₂/M phases increased, and apoptosis and necrosis remained unaffected. Accordingly, hyperosmotic conditions induced a decrease of cyclin B1 and D1 expression, and an activation of the p38 mitogen-activated protein kinase. In conclusion, our results demonstrate that hypertonic conditions profoundly affect RPE cell gene transcription regulating cell proliferation by downregulation cyclin D1 and cyclin B1 protein expression.

Glycerol metabolism alteration in adipocytes from n3-PUFA-depleted rats, an animal model for metabolic syndrome

Aquaglyceroporin 7 (AQP7) is a glycerol transporter expressed in adipocytes. Its expression has been shown to be modulated in obesity. Metabolic syndrome is characterized by abdominal obesity, insulin resistance, dyslipidemia, and hypertension. An animal model displaying several features of metabolic syndrome was used to study the AQP7 expression at both mRNA and protein level and glycerol flux in adipocytes. Second generation n3-PUFA depleted female rats is a good animal model for metabolic syndrome as it displays characteristic features such as liver steatosis, visceral obesity, and insulin resistance. Our data show a reduced expression of AQP7 at the protein level in adipose tissue from n3-PUFA-depleted rats, without any changes at the mRNA levels. [U-(14)C]-Glycerol uptake was not modified in adipocytes from n3-PUFA-depleted animals.

Recombinant TSH-Receptor for Determination of TSH-Receptor-Antibodies

We have expressed the complete coding sequence of the human TSH-R in eucaryotic cells. Limiting dilution enabled us to select two clones, JP09 and JP26, which have formed the basis of binding and bioassays respectively, for TSH-R antibodies. Results obtained in the binding assay correlated well with those obtained in the TRAK (Henning Berlin) assay, while the bioassay was at least as sensitive as measurements made with FRTL5 or human thyroid cells. These cell lines provide a reliable source of human TSH-R which will be useful in routine diagnosis.

[Treatments of hereditary hemorrhagic telangiectasia of the nasal mucosa]

Hereditary Hemorrhagic Telangiectasia is a systemic autosomal dominant disorder involving blood vessels. The most common symptom is recurrent epistaxis. The treatments of these epistaxis are numerous but such treatments are often symptomatic and their effects are often not sustained. Some of these treatments may be complicated by visceral vascular malformations. The aim of this study is to propose a treatment plan for these patients with hierarchical organisation of therapeutic options taking into account of their previous therapy.

METHOD

H. Plauchu organized in Paris, december 2002 a meeting with any medical specialists of this disease. They have analysed variety of therapies that have been proposed for epistaxis control in Hereditary Haemorrhagic Télangiectasia.

RESULTS

Most common use packing of nasal fossa and then hyperselective embolization of the internal maxillary and facial arteries for severe epistaxis. For chronic epistaxis, best treatment use sclerotics products (Ethibloc) and laser. After discussion, primary embolization could be useful to reduce vascularization of nasal fossa.

CONCLUSION

Treatment of epistaxis in Hereditary Haemorrhagic Telangiectasia could increase in few years. Use of an index card of for epistaxis in the disease of Rendu-Osler could help to find treatment of choice.

Lysine 195 and aspartate 196 in the first extracellular loop of the VPAC1 receptor are essential for high affinity binding of agonists but not of antagonists

The role in ligand recognition and receptor activation of two adjacent charged residues (lysine 195 and aspartate 196) in the first extracellular loop of the human VPAC(1) receptor was investigated in stably transfected CHO cells expressing the wild type or point mutated receptors.Replacement of lysine 195 by glutamine or of aspartate 196 by asparagine reduced the agonists' ability to stimulate adenylate cyclase activity; VIP behaved like a partial agonist and a partial agonist behaved as an antagonist. The receptor's capacity to recognize agonists was reduced but antagonists' affinity was unaffected. Both results suggesting that the two charged residues are essential for VPAC(1) receptor activation. On the other hand, the double mutant was less severely affected than single mutants suggesting that hydrogen bonds may partially compensate the loss of charged residues. But the inversion of the residues affected receptor recognition and activation more markedly suggesting that the two charged residues do not interact directly.

A small sequence in the third intracellular loop of the VPAC(1) receptor is responsible for its efficient coupling to the calcium effector

The stimulatory effect of vasoactive intestinal peptide (VIP) on the intracellular calcium concentration ([Ca(2+)](i)) has been investigated in Chinese hamster ovary cells stably transfected with the reporter gene aequorin, and expressing human VPAC(1), VPAC(2), chimaeric VPAC(1)/VPAC(2) or mutated receptors. The VIP-induced increase in [Ca(2+)](i) was linearly correlated with receptor density, and was higher in cells expressing VPAC(1) receptors than in cells expressing a similar density of VPAC(2) receptors. The study was performed to establish the receptor sequence responsible for this difference. VPAC(1)/VPAC(2) chimaeric receptors were first used for broad positioning: those receptors having the third intracellular loop (IC3) of the VPAC(1) or the VPAC(2) receptor behaved, in this respect, phenotypically like VPAC(1) and VPAC(2) receptors respectively. Replacement in the VPAC(2) receptor of the sequence comprising residues 315-318 (VGGN) within IC3 by its VPAC(1) receptor counterpart (residues 328-331; IRKS) and the introduction of VGGN instead of IRKS into VPAC(1) was sufficient to mimic VPAC(1) and VPAC(2) receptor characteristics respectively. Thus a small sequence in the IC3 domain of the VPAC(1) receptor is responsible for the efficient agonist-stimulated increase in [Ca(2+)](i).

Two tyrosine residues in the first transmembrane helix of the human vasoactive intestinal peptide receptors play a role in supporting the active conformation

1: We investigated the human vasoactive intestinal polypeptide (VIP) receptors VPAC(1) and VPAC(2) mutated at conserved tyrosine residues in the first transmembrane helix (VPAC(1) receptor Y146A and Y150A and VPAC(2) receptor Y130A and Y134A). 2: [(125)I]-Acetyl-His(1) [D-Phe(2), K(15), R(16), L(27)]-VIP (1-7)/GRF (8-27) (referred to as [(125)I]-VPAC(1) antagonist) labelled VPAC(1) binding sites, that displayed high and low affinities for VIP (IC(50) values and per cent of high affinity binding sites: wild-type, 1 nM (57+/-9%) and 160 nM; Y146A, 30 nM (40+/-8%) and 800 nM; Y150A, 4 nM (27+/-8%) and 300 nM). [R(16)]-VIP behaved as a "super agonist" at both mutated VPAC(1) receptors and the efficacies of VIP analogues modified in positions 1, 3 and 6 were significantly decreased. 3: VIP was less potent at the Y130A and Y134A mutated VPAC(2) receptors (EC(50) 200 and 400 nM, respectively) than at the wild-type VPAC(2) receptor (EC(50) 7 nM). Furthermore, [hexanoyl-His(1)]-VIP behaved as a "super agonist" at the two mutated VPAC(2) receptors, and VIP analogues modified in positions 1, 3 and 6 were less potent and efficient at the mutated than at wild-type VPAC(2) receptors. However, the Y130A and Y134A mutants could not be studied in binding assays. 4: Our results suggest that the conserved tyrosine residues do not interact directly with the VIP His(1), Asp(3) or Phe(6) residues (that are necessary for receptor activation), but stabilize the correct active receptor conformation.

Identification of secretin, vasoactive intestinal peptide and glucagon binding sites: from chimaeric receptors to point mutations

We have identified two basic residues that are important for the recognition of secretin and vasoactive intestinal peptide (VIP) by their respective receptors. These two peptides containing an Asp residue at position 3 interacted with an arginine residue in transmembrane helix 2 (TM2) of the receptor, and the lysine residue in extracellular loop 1 (ECL1) stabilized the active receptor conformation induced by the ligand. The glucagon receptor possesses a Lys instead of an Arg in TM2, and an Ile instead of Lys in ECL1; it markedly prefers a Gln side chain in position 3 of the ligand. Our results suggested that, in the wild-type receptor, the Ile side chain prevented access to the TM2 Lys side chain, but oriented the glucagon Gln(3) side chain to its proper binding site. In the double mutant, the ECL1 Lys allowed an interaction between negatively charged residues in position 3 of glucagon and the TM2 Arg, resulting in efficient receptor activation by [Asp(3)]glucagon as well as by glucagon.