Lung function changes in children exposed to mine fire smoke in infancy

BACKGROUND AND OBJECTIVE

Chronic, low-intensity air pollution exposure has been consistently associated with reduced lung function throughout childhood. However, there is limited research regarding the implications of acute, high-intensity air pollution exposure. We aimed to determine whether there were any associations between early life exposure to such an episode and lung growth trajectories.

METHODS

We conducted a prospective cohort study of children who lived in the vicinity of the Hazelwood coalmine fire. Lung function was measured using respiratory oscillometry. Z-scores were calculated for resistance (R5 ) and reactance at 5 Hz (X5 ) and area under the reactance curve (AX). Two sets of analyses were conducted: (i) linear regression to assess the cross-sectional relationship between post-natal exposure to mine fire-related particulate matter with an aerodynamic diameter of less than 2.5 micrometres (PM2.5 ) and lung function at the 7-year follow-up and (ii) linear mixed-effects models to determine whether there was any association between exposure and changes in lung function between the 3- and 7-year follow-ups.

RESULTS

There were no associations between mine fire-related PM2.5 and any of the lung function measures, 7-years later. There were moderate improvements in X5 (β: -0.37 [-0.64, -0.10] p = 0.009) and AX (β: -0.40 [-0.72, -0.08] p = 0.014), between the 3- and 7-year follow-ups that were associated with mean PM2.5 , in the unadjusted and covariance-adjusted models. Similar trends were observed with maximum PM2.5 .

CONCLUSION

There was a moderate improvement in lung stiffness of children exposed to PM2.5 from a local coalmine fire in infancy, consistent with an early deficit in lung function at 3-years after the fire that had resolved by 7-years.

No association between in utero exposure to emissions from a coalmine fire and post-natal lung function

BACKGROUND AND OBJECTIVE

Studies linking early life exposure to air pollution and subsequent impaired lung health have focused on chronic, low-level exposures in urban settings. We aimed to determine whether in utero exposure to an acute, high-intensity air pollution episode impaired lung function 7-years later.

METHOD

We conducted a prospective cohort study of children who lived in the vicinity of a coalmine fire. Respiratory function was measured using the forced oscillation technique (FOT). Z-scores for resistance at 5 Hz (R₅), reactance at 5 Hz (X₅) and area under the reactance curve (AX) were calculated. Two sets of analyses were conducted to address two separate questions: (1) whether mine fire exposure (a binary indicator; conceived after the mine fire vs in utero exposed) was associated with the respiratory Z-scores; (2) whether there was any dose-response relationship between fire-related PM_2.5 exposure and respiratory outcomes among those exposed.

RESULTS

Acceptable lung function measurements were obtained from 79 children; 25 unexposed and 54 exposed in utero. Median (interquartile range) for daily average and peak PM_2.5 for the exposed children were 4.2 (2.6 - 14.2) and 88 (52-225) µg/m³ respectively. There were no detectable differences in Z-scores between unexposed and exposed children. There were no associations between respiratory Z-scores and in utero exposure to PM_2.5 (daily average or peak).

CONCLUSION

There was no detectable effect of in utero exposure to PM_2.5 from a local coalmine fire on post-natal lung function 7-years later. However, statistical power was limited.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

1029 Evaluation of Significant Polyp and Early Colorectal Cancer (SPECC) MDT In A District General Hospital

Aim

There is an increase in the number of complex SPECC cases presented at colorectal MDT meetings with a wide variation in the treatments offered to patients, many of whom undergo high-risk and life-changing surgical resection. This study aimed to evaluate the detection, diagnosis and treatment of early colorectal cancer since the introduction of a SPECC MDT.

Method

This was a retrospective audit of 108 patients, from the SPECC MDT database from January 2014 to December 2019. Primary outcome assessed the recognition of lesions using endoscopy and radiological evaluation to assess depth of invasion and lymph node involvement. Secondary outcomes included definite treatment, pathological reporting and recurrence.

Results

Overall, mean age of 72, 79% had one or more significant co-morbidity. Clinical presentation; 61 asymptomatic, 46 symptomatic and 31 referred from the national bowel cancer-screening programme. All patients (n = 108) had endoscopic assessment the lesions were, 53% sessile and 47% pedunculated; 78% of the lesions were found in the rectum. We observed surgical management in 31 cases, endoscopic in 28, chemo-radiotherapy in 12 and 3 cases were palliative. However, 17 (n = 108) underwent failed endoscopic resection and required surgical intervention. Recurrence was observed in 17.6% of cases and mortality in 4%.

Conclusions

Pathological reports provide a definitive answer to questions of malignancy but SPECC can be challenging in all areas. A specialist MDT allows for appropriate assessment and treatment of lesions and leads to better patient outcomes.

Respiratory and atopic conditions in children two to four years after the 2014 Hazelwood coalmine fire

OBJECTIVE

To evaluate associations between exposure during early life to mine fire smoke and parent-reported indicators of respiratory and atopic illness 2-4 years later.

DESIGN, SETTING

The Hazelwood coalmine fire exposed a regional Australian community to markedly increased air pollution during February - March 2014. During June 2016 - October 2018 we conducted a prospective cohort study of children from the Latrobe Valley.

PARTICIPANTS

Seventy-nine children exposed to smoke in utero, 81 exposed during early childhood (0-2 years of age), and 129 children conceived after the fire (ie, unexposed).

EXPOSURE

Individualised mean daily and peak 24-hour fire-attributable fine particulate matter (PM_2.5 ) exposure during the fire period, based on modelled air quality and time-activity data.

MAIN OUTCOME MEASURES

Parent-reported symptoms, medications use, and contacts with medical professionals, collected in monthly online diaries for 29 months, 2-4 years after the fire.

RESULTS

In the in utero exposure analysis (2678 monthly diaries for 160 children exposed in utero or unexposed), each 10 μg/m³ increase in mean daily PM_2.5 exposure was associated with increased reports of runny nose/cough (relative risk [RR], 1.09; 95% CI, 1.02-1.17), wheeze (RR, 1.56; 95% CI, 1.18-2.07), seeking health professional advice (RR, 1.17; 95% CI 1.06-1.29), and doctor diagnoses of upper respiratory tract infections, cold or flu (RR, 1.35; 95% CI, 1.14-1.60). Associations with peak 24-hour PM_2.5 exposure were similar. In the early childhood exposure analysis (3290 diaries for 210 children exposed during early childhood, or unexposed), each 100 μg/m³ increase in peak 24-hour PM_2.5 exposure was associated with increased use of asthma inhalers (RR, 1.26; 95% CI, 1.01-1.58).

CONCLUSIONS

Exposure to mine fire smoke in utero was associated with increased reports by parents of respiratory infections and wheeze in their children 2-4 years later.

Early life exposure to coal mine fire and tobacco smoke affect subclinical vascular function

OBJECTIVE

To evaluate whether vascular health in young children was associated with exposure to a 6-week episode of coal mine fire smoke or environmental tobacco smoke (ETS) in a retrospective cohort study.

METHODS

Three years after a coal mine fire in Victoria, Australia, we investigated the vascular health of children either in utero (n=75) or aged <2 years (postnatal exposure, n=96) at the time of the fire. The outcomes were the carotid intima-media thickness (IMT) and pulse wave velocity (PWV). The mean and peak daily particulate matter <2.5 µm in diameter (PM_2.5) exposures were estimated based on their daily locations throughout the fire period. Multivariable linear regression models were used to test for associations between the fire-related PM_2.5 and outcomes adjusted for relevant covariates including ETS.

RESULTS

In the postnatal-exposure group, each 10 µg/m³ increase in mean PM_2.5 level was independently positively associated with PWV (β=0.116, p=0.028). When these two groups were combined, there was an association between mean PM_2.5 and increased PWV in those children who had ETS exposure (β=0.148, p=0.033) or whose mothers smoked (β=0.151, p=0.011), but not in those not exposed to ETS or maternal smoking.

CONCLUSIONS

Three years after a coal mine fire, infants aged up to 2 years at the time of exposure have increases in vascular stiffness. Although no adverse effects were observed in the in uterus exposure group, further follow-up study is needed to elucidate the long-term effects of coal mine fire smoke exposure.

Exposure to air pollution during the first 1000 days of life and subsequent health service and medication usage in children

BACKGROUND

Evidence of health effects following early life exposure to short-to-medium duration of high pollution levels is extremely limited.

OBJECTIVES

We aimed to evaluate the associations between: 1. intrauterine exposure to fine particulate matter (PM_2.5) from coal mine fire emissions and the frequencies of general practitioner attendances and dispensations of prescribed asthma inhalers, steroid skin creams, and antibiotics during the first year of life; 2. infant exposure and those outcomes during the year following the fire.

METHODS

All participants were recruited from the Latrobe Valley of Victoria, Australia. Participants' 24-h average and hourly peak mine fire-specific PM_2.5 exposures from 09/02/2014 to 31/03/2014 were estimated using chemical transport modelling. Outcome data were obtained from the Australian Medicare Benefits Schedule and Pharmaceutical Benefits Scheme from each child's birth to 31/12/2016. We used negative binomial and logistic regression models to independently assess risks of the outcomes associated with every 10 and 100 μg m^-3 increase in average or peak PM_2.5 exposure, respectively, while adjusting for potential confounders.

RESULTS

We included 286 of 311 children whose parents consented to be linked, comprising 77 with no exposure, 88 with intrauterine exposure and 121 with exposure in infancy. 10- and 100- μg m^-3 increases in average and peak PM_2.5 exposure during infancy were associated with greater incidence of antibiotics being dispensed during the year following the fire: the adjusted incidence rate ratios were 1.24 (95% CI 1.02, 1.50, p = 0.036) and 1.14 (1.00, 1.31, p = 0.048) respectively. No other significant associations were observed.

CONCLUSION

Exposure to coal mine fire emissions during infancy was associated with increased dispensing of antibiotics. This could reflect increased childhood infections or increased prescriptions of antibiotics in the year following the fire.

Inferred cosmic-ray spectrum from Fermi large area telescope γ-ray observations of Earth's limb

Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly discovered features may offer a clue to the origin of high-energy CRs. We use the Fermi Large Area Telescope observations of the γ-ray emission from Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range ∼90  GeV-6  TeV (derived from a photon energy range 15 GeV-1 TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index 2.68±0.04 and 2.61±0.08 above ∼200  GeV, respectively.

Search for photon-linelike signatures from dark matter annihilations with H.E.S.S

Gamma-ray line signatures can be expected in the very-high-energy (E(γ)>100 GeV) domain due to self-annihilation or decay of dark matter (DM) particles in space. Such a signal would be readily distinguishable from astrophysical γ-ray sources that in most cases produce continuous spectra that span over several orders of magnitude in energy. Using data collected with the H.E.S.S. γ-ray instrument, upper limits on linelike emission are obtained in the energy range between ∼ 500 GeV and ∼ 25 TeV for the central part of the Milky Way halo and for extragalactic observations, complementing recent limits obtained with the Fermi-LAT instrument at lower energies. No statistically significant signal could be found. For monochromatic γ-ray line emission, flux limits of (2 × 10(-7) -2 × 10(-5)) m(-2) s(-1) sr(-1) and (1 × 10(-8) -2 × 10(-6)) m(-2) s(-1)sr(-1) are obtained for the central part of the Milky Way halo and extragalactic observations, respectively. For a DM particle mass of 1 TeV, limits on the velocity-averaged DM annihilation cross section ⟨σv⟩(χχ → γγ) reach ∼ 10(-27) cm(3)s(-1), based on the Einasto parametrization of the Galactic DM halo density profile.

The association between parity and knee cartilage in young women

OBJECTIVES

There have been no reported studies of the association between parity and cartilage in young individuals. The aim of this study was to describe the association between parity, cartilage volume and cartilage defects in women aged 31-41 years.

METHODS

Cross-sectional study of 144 women, mean age 36 years and BMI 25 kg/m(2), who were participants in an established prospective study. Parity was assessed using a questionnaire. Knee (medial tibial, lateral tibial and patellar) cartilage volume, cartilage defects (grade 0-4 depending on the severity of cartilage thickness loss at tibial and patellar sites) and tibial bone area were assessed using T1-weighted fat-suppressed MRI.

RESULTS

The prevalence of cartilage defects (grade ≥2) in this population was 13%. Parity was associated with a higher risk of cartilage defects at the patellar [prevalence ratio (PR) per birth 1.52, 95% CI 1.05, 2.21; PR parous vs nulliparous 1.93, 95% CI 0.66, 5.65], but not tibial sites, after adjustment for confounders including age, BMI, smoking, physical activity, knee injury and tibial bone area. This association between parity and patellar cartilage defects was stronger for those women who had three or more births (vs nulliparous, PR 5.27, 95% CI 1.39, 20.01). There were no significant associations between parity and cartilage volume.

CONCLUSION

Parity was associated with knee cartilage defects primarily at the patellar site in this sample of young women. This association was more apparent with increasing number of live births, suggesting a possible adverse effect of parity on knee cartilage.

Cytotoxic drugs for patients with breast cancer in the era of targeted treatment: back to the future?

BACKGROUND

Despite current trend of targeted therapy development, cytotoxic agents are a mainstay of treatment of patients with breast cancer. We reviewed recent advances in cytotoxic therapy for patients with metastatic breast cancer (MBC).

MATERIALS AND METHODS

Medline searches were conducted for English language studies using the term 'MBC' and 'cytotoxic drugs'. The data search was restricted to the period 2000-2011.

RESULTS

Several novel cytotoxic compounds, all microtubule inhibitors, have been approved for clinical use in MBC: (i) nab-paclitaxel, reported to improve tumour response and decrease hypersensitivity reactions in comparison with other taxanes; (ii) ixabepilone, shown to have clinical benefit in taxane- and anthracycline-resistant disease and (iii) eribulin, shown to improve overall survival in heavily pre-treated patients, when compared with best available standard treatment. Agents, such as larotaxel, vinflunine, trabectidin and formulations, including cationic liposomal paclitaxel or paclitaxel poliglumex, are currently under evaluation in phase II/III trials.

CONCLUSION

Toxicity and chemotherapy resistance are still major limitations in the treatment of patients with MBC. Further research into new cytotoxic compounds is needed in order to maximise benefit, whilst minimising toxicity.

Search for a dark matter annihilation signal from the galactic center halo with H.E.S.S

A search for a very-high-energy (VHE; ≥100  GeV) γ-ray signal from self-annihilating particle dark matter (DM) is performed towards a region of projected distance r∼45-150  pc from the Galactic center. The background-subtracted γ-ray spectrum measured with the High Energy Stereoscopic System (H.E.S.S.) γ-ray instrument in the energy range between 300 GeV and 30 TeV shows no hint of a residual γ-ray flux. Assuming conventional Navarro-Frenk-White and Einasto density profiles, limits are derived on the velocity-weighted annihilation cross section (σv) as a function of the DM particle mass. These are among the best reported so far for this energy range and in particular differ only little between the chosen density profile parametrizations. In particular, for the DM particle mass of ∼1  TeV, values for (σv) above 3×10(-25)  cm(3) s(-1) are excluded for the Einasto density profile.

Energy spectrum of cosmic-ray electrons at TeV energies

The very large collection area of ground-based gamma-ray telescopes gives them a substantial advantage over balloon or satellite based instruments in the detection of very-high-energy (>600 GeV) cosmic-ray electrons. Here we present the electron spectrum derived from data taken with the High Energy Stereoscopic System (H.E.S.S.) of imaging atmospheric Cherenkov telescopes. In this measurement, the first of this type, we are able to extend the measurement of the electron spectrum beyond the range accessible to direct measurements. We find evidence for a substantial steepening in the energy spectrum above 600 GeV compared to lower energies.

Limits on an energy dependence of the speed of light from a flare of the active galaxy PKS 2155-304

In the past few decades, several models have predicted an energy dependence of the speed of light in the context of quantum gravity. For cosmological sources such as active galaxies, this minuscule effect can add up to measurable photon-energy dependent time lags. In this Letter a search for such time lags during the High Energy Stereoscopic System observations of the exceptional very high energy flare of the active galaxy PKS 2155-304 on 28 July 2006 is presented. Since no significant time lag is found, lower limits on the energy scale of speed of light modifications are derived.

A phase II trial of intra-patient dose-escalated sorafenib in patients (pts) with metastatic renal cell cancer (MRCC)

5026

Background: Sorafenib has demonstrated activity with limited toxicity at a dose of 400 mg bid in MRCC pts. This presents an opportunity to explore a more intensive drug administration. This study allowed individual pt titration designed to evaluate the ability for pts to dose escalate. Response rate (RR), time to progression (TTP) and overall survival (OS) will be assessed. Methods: Eligibility included; pathologic diagnosis of a component of clear cell, progressive measurable MRCC, no more than 1 prior therapy, karnofsky performance status (KPS) = 70%, adequate organ/marrow function and no active CNS involvement. Initial dose 400 mg bid, daily. Dose escalation defined in the table below: Re-evaluation is performed every 8 weeks. RECIST criteria is utilized. Results: 46 patients have been enrolled. 44 are evaluable. 37 male/7 female, median age 50 years (43–79). 19 pts received prior therapy. 39 pts had a KPS of 100%, 5/90%. Sites of disease included; lung, nodal, liver, bone, adrenal, pancreas and kidney. 26 pts 1 metastatic site, 12 /2, 6/3 or more. 22 pts continue to receive sorafenib therapy; 2/800 mg, 7/1,200 mg, and 13/1,600 mg. 8 pts complete response (CR), 14 pts/partial response (PR) and 14 pts stable for 3+ months. Median duration of therapy is 6+ (range 0.2+ - 12+) months. 2 pts have not been reevaluated. Treatment related adverse events to-date; hand/foot syndrome, skin rash, diarrhea, alopecia, fatigue, hypertension, hypophosphatemia, and elevated amylase/lipase. Conclusion: 91% of pts were escalated to 1,200 mg or 1,600 mg per day. Dose escalated sorafenib has promising anti-tumor activity in pts with MRCC as demonstrated by a 52% CR/PR rate. Anti-tumor activity is further suggested by prolonged TTP = 3 months for 33% of pts. Independent radiology review is in progress. Intra-patient dose escalation data in association with anti-tumor activity and toxicity will be presented.

[Table: see text]

[Table: see text]

Disordered eating behaviours in women with Type 2 diabetes mellitus

The aim of the article is to investigate the relationship between disordered eating, particularly binge eating, and Type 2 diabetes in women. Subjects included 215 women with Type 2 diabetes (mean age: 58.9 years, mean body mass index (BMI)=33.5 kg/m(2)). Measurements included a structured clinical interview for disordered eating (Eating Disorder Examination, EDE), self-report measures of psychological functioning, glycosylated haemoglobin A1c, BMI. A total of 20.9% of women was binge eating regularly. Binge eating was associated with poorer well being, earlier age of diagnosis, poorer self-efficacy for diet and exercise self-management, and higher BMI. Binge eating frequency predicted blood glucose control after controlling for BMI and exercise level. A history of binge eating independently predicted age of diagnosis of diabetes. Binge eating is relatively common in women with Type 2 diabetes. The relationship between binge eating severity and diabetic control is not explained by overweight. Binge eating may be an independent risk factor for Type 2 diabetes.

Waist circumference, waist-hip ratio and body mass index and their correlation with cardiovascular disease risk factors in Australian adults

OBJECTIVES

To compare body mass index (BMI), waist circumference and waist-hip ratio (WHR) as indices of obesity and assess the respective associations with type 2 diabetes, hypertension and dyslipidaemia.

DESIGN AND SETTING

A national sample of 11 247 Australians aged > or =25 years was examined in 2000 in a cross-sectional survey.

MAIN OUTCOME MEASURES

The examination included a fasting blood sample, standard 2-h 75-g oral glucose tolerance test, blood pressure measurements and questionnaires to assess treatment for dyslipidaemia and hypertension. BMI, waist circumference and WHR were measured to assess overweight and obesity.

RESULTS

The prevalence of obesity amongst Australian adults defined by BMI, waist circumference and WHR was 20.8, 30.5 and 15.8% respectively. The unadjusted odds ratio for the fourth vs. first quartile of each obesity measurement showed that WHR had the strongest relationship with type 2 diabetes, dyslipidaemia (women only) and hypertension. Following adjustment for age, however, there was little difference between the three measures of obesity, with the possible exceptions of hypertension in women, where BMI had a stronger association, and dyslipidaemia in women and type 2 diabetes in men, where WHR was marginally superior.

CONCLUSIONS

Waist circumference, BMI and WHR identified different proportions of the population, as measured by both prevalence of obesity and cardiovascular disease (CVD) risk factors. Whilst WHR had the strongest correlations with CVD risk factors before adjustment for age, the three obesity measures performed similarly after adjustment for age. Given the difficulty of using age-adjusted associations in the clinical setting, these results suggest that given appropriate cut-off points, WHR is the most useful measure of obesity to use to identify individuals with CVD risk factors.

Effect of protease inhibitor-containing regimens on lymphocyte multidrug resistance transporter expression

BACKGROUND

Increased expression of multidrug resistance transporters, such as P-glycoprotein (P-gp), has been suggested as a potential mechanism for decreased protease inhibitor (PI) availability at certain intracellular sites and tissue compartments.

OBJECTIVES

To investigate the effect of PIs on the surface lymphocyte expression of P-gp in vitro and in vivo.

PATIENTS AND METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from healthy subjects (n = 15) and incubated (72 h) with 10 microM of each PI studied (saquinavir, ritonavir, nelfinavir, indinavir, amprenavir and lopinavir), or dimethyl sulphoxide (DMSO) control. PBMCs were also isolated from HIV-infected subjects (n = 50; viral load <50 copies/mL) on a PI- or a non-PI-containing combination antiretroviral regimen. P-gp expression was analysed by flow cytometry.

RESULTS

No differences in surface P-gp expression on lymphocytes, CD4+ or CD8+ lymphocyte subsets were observed following incubation with 10 microM saquinavir, ritonavir, indinavir, amprenavir or lopinavir in vitro. Nelfinavir, however, increased P-gp expression. In vivo, no difference in P-gp expression on total lymphocytes was observed between patients receiving a PI-containing regimen [saquinavir n = 9, ritonavir n = 6, nelfinavir n = 7, indinavir n = 7 and lopinavir/ritonavir n = 13, and two nucleoside reverse transcriptase inhibitors (NRTIs)] and patients receiving a control regimen of three NRTIs alone (n = 8).

CONCLUSION

This study suggests that, of the PIs, only nelfinavir increases P-gp expression in vitro, and in vivo the PI class of antiretrovirals do not increase P-gp expression on lymphocytes. It is clear that factors other than PI induction are important in the inter-individual variability in the lymphocyte expression of P-gp.

Overweight and obesity in Australia: the 1999-2000 Australian Diabetes, Obesity and Lifestyle Study (AusDiab)

OBJECTIVE

To measure the prevalence of obesity in Australian adults and to examine the associations of obesity with socioeconomic and lifestyle factors.

DESIGN

AusDiab, a cross-sectional study conducted between May 1999 and December 2000, involved participants from 42 randomly selected districts throughout Australia.

PARTICIPANTS

Of 20,347 eligible people aged > or = 25 years who completed a household interview, 11,247 attended the physical examination at local survey sites (response rate, 55%).

MAIN OUTCOME MEASURES

Overweight and obesity defined by body mass index (BMI; kg/m(2)) and waist circumference (cm); sociodemographic factors (including smoking, physical activity and television viewing time).

RESULTS

The prevalence of overweight and obesity (BMI > or = 25.0 kg/m(2); waist circumference > 80.0 cm [women] or > or = 94.0 cm [men]) in both sexes was almost 60%, defined by either BMI or waist circumference. The prevalence of obesity was 2.5 times higher than in 1980. Using waist circumference, the prevalence of obesity was higher in women than men (34.1% v 26.8%; P < 0.01). Lower educational status, higher television viewing time and lower physical activity time were each strongly associated with obesity, with television viewing time showing a stronger relationship than physical activity time.

CONCLUSIONS

The prevalence of obesity in Australia has more than doubled in the past 20 years. Strong positive associations between obesity and each of television viewing time and lower physical activity time confirm the influence of sedentary lifestyles on obesity, and underline the potential benefits of reducing sedentary behaviour, as well as increasing physical activity, to curb the obesity epidemic.

Subject discomfort associated with the histamine challenge in a population study

BACKGROUND

Many review articles report the safety and lack of serious side-effects associated with the histamine challenge. Even though methacholine and hypertonic saline are more commonly used to measure airway responsiveness, histamine challenges are used in many countries around the world. Levels of subjects discomfort after a challenge have not been quantified. This study quantified the incidence, severity and duration of subject discomfort after histamine challenge.

METHODS

Ninety-nine subjects were recruited in an Australian multi-centre population-based study of the genetic epidemiology of asthma. Subjects completed a histamine challenge with final cumulative dose 3.2 micromol. Immediately, and 10 min, after challenge subjects rated their discomfort for cough, headache, throat irritation, hoarse voice and flushed. Research personnel also reported their perception of subjectdiscomfort.

RESULTS

Subjects and research personnel reported a small degree of subject discomfort for all symptoms immediately after the histamine challenge. Overall, median symptom scores were less than 1.5 out of 10. Discomfort scores improved 10 min after challenge and cough, throat irritation and flushed improved significantly

CONCLUSIONS

This study confirms the tolerability of the histamine challenge.

Reasons for non-adherence to antiretroviral therapy: patients' perspectives provide evidence of multiple causes

The objective of the study was to define common reasons for non-adherence (NA) to highly active antiretroviral therapy (HAART) and the number of reasons reported by non-adherent individuals. A confidential questionnaire was administered to HIV-seropositive patients taking proteinase inhibitor based HAART. Median self-reported adherence was 95% (n = 178, range = 60-100%). The most frequent reasons for at least 'sometimes' missing a dose were eating a meal at the wrong time (38.2%), oversleeping (36.3%), forgetting (35.0%) and being in a social situation (30.5%). The mean number of reasons occurring at least 'sometimes' was 3.2; 20% of patients gave six or more reasons; those reporting the lowest adherence reported a significantly greater numbers of reasons (rho = - 0.59; p < 0.001). Three factors were derived from the data by principal component analysis reflecting 'negative experiences of HAART', 'having a low priority for taking medication' and 'unintentionally missing doses', accounting for 53.8% of the variance. On multivariate analysis only the latter two factors were significantly related to NA (odds ratios 0.845 and 0.849, respectively). There was a wide spectrum of reasons for NA in our population. The number of reasons in an individual increased as adherence became less. A variety of modalities individualized for each patient are required to support patients with the lowest adherence.

Does parental disapproval of smoking prevent adolescents from becoming established smokers?

OBJECTIVE

To evaluate the hypothesis that adolescents are less likely to smoke if their parents voice strong disapproval of smoking.

DESIGN AND SETTING

Three-wave school-based cohort study of rural Vermont adolescents attending 3 K-12 schools. We evaluate cross-sectional and longitudinal associations between perceived parental disapproval of smoking and the adoption of smoking behavior.

OUTCOME MEASURES

Students' perceptions of their parents' reaction to their own smoking was ascertained by asking the following question for mothers and fathers: "How do you think your mother (father) would react if you were smoking cigarettes and she (he) knew about it?" A response of "S/he would tell me to stop and be very upset" was considered to indicate strong parental disapproval. Outcome measures include a 6-level smoking index for cross-sectional analyses and, for a longitudinal analysis of 372 never smokers at baseline, being an established smoker (smoked > or =100 cigarettes lifetime and within the past 30 days) by survey 3.

RESULTS

The study samples for the cross-sectional analyses were 662 (baseline), 758 (year 2), and 730 (year 3). Students were equally distributed across grade (4th-11th grades) and gender. At baseline, most (65.9%) adolescents perceived both parents as disapproving of smoking, with 110 (16.6) perceiving 1 parent as disapproving, and 116 (17.5%) perceiving neither parent as disapproving. Perceived disapproval of smoking was inversely associated with adolescent smoking, grade in school, parental and sibling smoking, friend smoking, and ownership of tobacco promotional items. After controlling for confounding influences, adolescents who perceived strong parental disapproval of their smoking were less than half as likely to have higher smoking index levels compared with those who did not perceive strong parental disapproval. In the longitudinal sample of baseline never smokers, those who perceived strong disapproval in both parents at baseline were less than half as likely to become established smokers (adjusted odds ratio 0.4 [0.1, 1.0]). Those who perceived their parents becoming more lenient over time were significantly more likely to progress to established smokers. In all analyses, the effect of parental disapproval of smoking was stronger and more robust than the effect of parent smoking. In addition, the effect of parent disapproval was as strong for parents who smoked as it was for nonsmoking parents. An interaction analysis suggests that the peer smoking effect is attenuated when both parents strongly disapprove of smoking, suggesting that parent disapproval makes adolescents more resistant to the influence of peer smoking.

CONCLUSIONS

These findings contrast with the widespread notion that there is little parents can do to prevent their adolescents from becoming smokers. Instead, adolescents who perceive that both parents would respond negatively and be upset by their smoking are less likely to smoke. Interventions that enhance parental self-efficacy in conveying and enforcing no-smoking policies for their children could reduce adolescent smoking.

Homocysteine inhibits retinoic acid synthesis: a mechanism for homocysteine-induced congenital defects

Hyperhomocysteinemia is frequently associated with congenital defects of the heart and neural tube and is a suspected pathogenic factor in atherosclerosis and neoplasia. Results in the present report show homocysteine treatment disrupts normal development of avian embryos; and this effect is prevented by retinoic acid. Based on this, we hypothesize that homocysteine may exert its teratogenic effects by disrupting retinoic acid signaling during development. A reporter cell line transfected with a retinoic acid response element (RARE) linked to a lacZ reporter gene was used to identify the site of retinoid inhibition. Using this reporter cell line, we show that homocysteine inhibits the oxidation of retinal to retinoic acid with concentrations of homocysteine that are in the pathophysiological range (.05 to 0.5 mM). In contrast, homocysteine concentrations as high as 5 mM are unable to inhibit the induction of lacZ by retinoic acid. We show that cellular uptake of homocysteine is sensitive to the specific L-system transport inhibitor, bicycloheptane, and bicycloheptane blocks the inhibition of retinoic acid synthesis by homocysteine, demonstrating that this inhibition occurs intracellularly. These results suggest that homocysteine-induced congenital defects are due to the specific ability of homocysteine to inhibit conversion of retinal to retinoic acid.

Exposure to cigarette promotions and smoking uptake in adolescents: evidence of a dose-response relation

OBJECTIVE

To assess whether a dose-response relation exists between the number of cigarette promotional items (CPIs) owned by an adolescent, and smoking behaviour.

DESIGN AND SETTING

Voluntary, self administered survey of 1265 sixth through to 12th grade students (ages 10-19 years), representing 79-95% of all students attending five rural New Hampshire and Vermont public (state funded) schools in October 1996. The association between the number of CPIs owned by students and smoking behaviour was examined using multivariate regression methods.

OUTCOME MEASURES

Adjusted odds of being a smoker (>/= 100 cigarettes lifetime) and, among never and experimental smokers, adjusted cumulative odds of having higher levels on a smoking uptake index given the number of CPIs owned.

RESULTS

One third of students owned a CPI (n = 406). Among owners, 211 owned one, 82 owned two, 57 owned three, 24 owned four, 23 owned five, and 7 students owned six CPIs. The number of CPIs owned by students was not associated with grade in school but was significantly higher in males, those with poorer school performance, those who perceived high prevalence of peer smoking, and those with higher exposure to peer and family smoking. The more items a student owned, the greater the chances of being a smoker. For example, smoking prevalence was 11.2% for those not owning a CPI, 41.5% for those owning two, 58.5% for those owning four, and 71.4% for those owning six CPIs. The dose-response relation remained after controlling for confounding; compared with those who did not own a CPI, the likelihood of being a smoker was significantly higher for those who owned one CPI, with an adjusted odds ratio (OR) of 2.7 (95% confidence interval (CI) 1.7 to 4.1); OR was 3.4 (95% CI 1.9 to 5.9) for those owning two CPIs, and 8.4 (95% CI 5.0 to 14.2) for those owning three or more CPIs. After excluding smokers, there was a crude dose-response association between CPI ownership and higher rates of experimentation with cigarettes among sixth to ninth graders (ages 11-15 years) only (n = 543). After controlling for confounding influences, the dose-response relation remained, with the likelihood of being higher on the smoking uptake index rising with the number of CPIs owned: one CPI, adjusted cumulative OR 1.7 (95% CI 1.1 to 2.60); two CPIs, OR 2.5 (95% CI 1.2 to 5.1); and three or more CPIs, OR 4.8 (95% CI 1.9 to 12.2).

CONCLUSIONS

This study offers evidence of a dose-response relation between the number of CPIs owned by adolescents and higher likelihood of experimental and established smoking. The dose-response relation persists after controlling for confounding influences. These data provide further support of a causal relation between tobacco promotional campaigns and smoking behaviour among adolescents.

Effect of cigarette promotions on smoking uptake among adolescents

BACKGROUND

The purpose of this study was to evaluate the association between receptivity to cigarette promotions and smoking uptake in a cohort of adolescents.

METHODS AND MEASURES

This was a prospective cohort study of 480 4th- to 11th-grade students conducted in three rural Vermont K-12 schools. Cigarette use was determined by self-report at baseline, 12 months (survey 2), and 21 months (survey 3). Proportional odds models were used to evaluate smoking uptake as a function of baseline measures of cigarette use, receptivity to cigarette promotions, and confounding factors, including grade, parental education, peer smoking, and family smoking. Adolescents were receptive to cigarette promotions if they owned or were willing to use a personal item bearing a cigarette brand logo [cigarette promotional item (CPI)]. Smoking status was measured using a 6-point ordinal index that combined experience and attitudes: 0 = never smoker/not susceptible to smoking, 1 = never smoker/susceptible to smoking, 2 = puffer (1 cigarette or less in lifetime), 3 = non-current experimenter (2-99 cigarettes in lifetime/none in past 30 days), 4 = current experimenter, and 5 = smoker (> or =100 cigarettes in lifetime).

RESULTS

The 480 students were equally distributed across grade at baseline. Environmental exposure to smoking was high, and 30% were receptive to cigarette promotions at baseline. Higher levels on the smoking index at baseline were associated with higher grade in school, peer smoking, and receptivity to cigarette promotions. One hundred eighty-five students (38.5%) had moved to a higher category on the smoking index by survey 3, of whom 30 had become smokers. Receptivity to cigarette promotions at baseline was significantly associated with higher smoking uptake, with 48.7% of receptive students moving up one or more categories on the smoking index [adjusted proportional odds 1.9 (95% CI 1.3, 2.9)]. Acquisition of receptivity to cigarette promotions was also associated with increased smoking uptake, with those becoming receptive in surveys 2 or 3 having significantly higher odds of progression [3.6 (1.8, 7.0) and 2.9 (1.5, 5.5), respectively] compared with those who did not change. Conversely, those who were receptive at one point but became non-receptive in surveys 2 or 3 had lower odds of progression [0.4 (0.2, 0.9) and 0.5 (0.3, 1.1), respectively].

CONCLUSIONS

This study supports a close linkage between tobacco promotional activities and uptake of smoking among adolescents beyond baseline descriptions of receptivity to cigarette promotions. Over time, the likelihood of smoking uptake is increased when an adolescent acquires a CPI or becomes willing to use one and is decreased when an adolescent who owns a CPI loses it or becomes unwilling to use it. This provides strong evidence that elimination of cigarette promotional campaigns could reduce adolescent smoking.

The association between state housing policy and lead poisoning in children

OBJECTIVES

This study examined the effect of an active program of household lead paint hazard abatement, applied over 22 years, on childhood lead poisoning in Massachusetts.

METHODS

A small areas analysis was used to compare screening blood lead levels of children in Worcester County, Mass (n = 27,590), with those in Providence County, RI (n = 19,071). Data were collapsed according to census tract.

RESULTS

The percentage of children with lead poisoning (blood lead level > or = 20 micrograms/dL [Pe20]) was, on average, 3 times higher in Providence County census tracts (3.2% vs 0.9% in Worcester County census tracts, P < .0001), despite similar percentages of pre-1950s housing in both counties. The ratio of Pe20 in Providence vs Worcester County census tracts was 2.2 (95% confidence interval = 1.8, 2.7), after adjustment for differences in housing, sociodemographic, and screening characteristics. This estimate was robust to alternative regression methods and sensitivity analyses.

CONCLUSIONS

Massachusetts policy, which requires lead paint abatement of children's homes and places liability for lead paint poisoning on property owners, may have substantially reduced childhood lead poisoning in that state.

Diagnostic testing unwarranted for children with blood lead 10 to 14 microg/dL

BACKGROUND

Recent statements from the American Academy of Pediatrics and Centers for Disease Control and Prevention recommend diagnostic venous blood lead testing within 90 days of a marginally elevated screening test (10-14 microg/dL).

OBJECTIVE

To evaluate the ability of a marginally elevated capillary (CScr) or venous (VScr) blood lead screening test to predict venous diagnostic (VPb) blood lead (taken within 90 days of the screening test) that would prompt environmental evaluation (>/=20 microg/dL).

DESIGN

Population-based follow-up study comparing CScr and VScr with VPb drawn within 90 days of the screening sample. This study population was drawn from all children aged 0 to 4 years who were screened in Worcester County, Massachusetts, and Providence County, Rhode Island, with CScr and VScr during calendar year 1994.

OUTCOME MEASURES

To evaluate predictive validity, CScr and VScr were correlated with VPb. CScr, VScr, and VPb results were then separated into the following categories: <10, 10 to 14, 15 to 19, and >/=20 microg/dL. CScr and VScr categories were cross-tabulated against VPb categories, and logistic regression analysis was used to evaluate categorical elevations of CScr and VScr as predictors of VPb >/=20 microg/dL.

RESULTS

Of 31 904 children screened with CScr, 5450 (17.1%) were elevated and 1278 were followed up with VPb within 90 days. Of 14 623 children screened with VScr, 2979 (20.4%) were elevated and 614 were followed up with VPb within 90 days. CScr was only weakly correlated with VPb (r = 0.39), whereas VScr was more strongly correlated with VPb (r = 0.73). Compared with CScr <10 microg/dL, CScr in the 10 to 14 microg/dL range did not identify a higher percentage of children with VPb elevation in any category, and falsely misclassified as lead poisoned some 77% of children. Compared with VScr <10 microg/dL, VScr in the 10 to 14 microg/dL range identified higher percentages of children with VPb in the 10 to 19 microg/dL range but not with VPb >/=20 microg/dL, and falsely misclassified as lead poisoned 42% of children. Compared with screening tests <10 microg/dL, the odds of identifying a child with VPb >/=20 were no different from 1 for CScr of 10 to 14 microg/dL (adjusted odds ratio 1.4 [95% confidence interval 0.3, 6.6]), CScr of 15 to 19 microg/dL (3.2 [0.7, 15.7]), or VScr of 10 to 14 microg/dL (0.9 [0.3, 3.0]). CScr and VScr in the 15 to 19 microg/dL range were associated with significantly higher odds of having VPb >/=20 microg/dL when compared with screening tests <10 microg/dL.

CONCLUSIONS

These data indicate that special diagnostic testing within 90 days for children with CScr and VScr in the 10 to 14 microg/dL range does not result in greater identification of VPb >/=20. Raising the set point for diagnostic testing to 15 microg/dL in this sample would eliminate the unnecessary follow-up of 5162 children, of whom 3360 were falsely misclassified as having undue lead exposure.

High concentrations of heavy metals in neighborhoods near ore smelters in northern Mexico

In developing countries, rapid industrialization without environmental controls has resulted in heavy metal contamination of communities. We hypothesized that residential neighborhoods located near ore industries in three northern Mexican cities would be heavily polluted with multiple contaminants (arsenic, cadmium, and lead) and that these sites would be point sources for the heavy metals. To evaluate these hypotheses, we obtained samples of roadside surface dust from residential neighborhoods within 2 m of metal smelters [Torreón (n = 19)] and Chihuahua (n = 19)] and a metal refinery [Monterrey (n = 23)]. Heavy metal concentrations in dust were mapped with respect to distance from the industrial sites. Correlation between dust metal concentration and distance was estimated with least-squares regression using log-transformed data. Median dust arsenic, cadmium, and lead concentrations were 32, 10, and 277 microg/g, respectively, in Chihuahua; 42, 2, and 467 microg/g, respectively, in Monterrey, and 113, 112, and 2,448 microg/g, respectively, in Torreón. Dust concentrations of all heavy metals were significantly higher around the active smelter in Torreón, where more than 90% of samples exceeded Superfund cleanup goals. At all sites, dust concentrations were inversely related to distance from the industrial source, implicating these industries as the likely source of the contamination. We concluded that residential neighborhoods around metal smelting and refining sites in these three cities are contaminated by heavy metals at concentrations likely to pose a health threat to people living nearby. Evaluations of human exposure near these sites should be conducted. Because multiple heavy metal pollutants may exist near smelter sites, researchers should avoid attributing toxicity to one heavy metal unless others have been measured and shown not to coexist.

Phosphorylation of Tyr319 in ZAP-70 is required for T-cell antigen receptor-dependent phospholipase C-gamma1 and Ras activation

Accumulating evidence indicates that the interdomain B regions of ZAP-70 and Syk play pivotal roles in the coupling of T-cell antigen receptor (TCR) stimulation to the activation of downstream signaling pathways. The interdomain B region of ZAP-70 contains at least three candidate sites of tyrosine phosphorylation. In this report, we identify Tyr319 as a functionally important phosphorylation site in the ZAP-70 interdomain B region. TCR crosslinkage triggered a rapid increase in the phosphorylation of Tyr319 in Jurkat T cells. Although mutation of Tyr319 to Phe had no effect on the tyrosine kinase activity of ZAP-70, the resulting ZAP(Y319-->F) mutant failed to reconstitute TCR-dependent Ca2+ mobilization, Ras activation, CD69 expression and NFAT-dependent transcription in ZAP-70-deficient Jurkat cells. These defects were correlated with reduced tyrosine phosphorylation of phospholipase C (PLC)-gamma1 and the LAT adapter protein in the ZAP(Y319-->F)-expressing cells. On the other hand, ZAP(Y319-->F)-expressing cells displayed normal increases in SLP-76 phosphorylation and ERK activation during TCR stimulation. Phosphorylation of Tyr319 promoted the association of ZAP-70 with the SH2 domains of two key signaling molecules, Lck and PLC-gamma1. These studies suggest that Tyr319 phosphorylation is required for the assembly of a ZAP-70-containing signaling complex that leads to the activation of the PLC-gamma1- and Ras-dependent signaling cascades in antigen-stimulated T cells.

Early use of inhaled nedocromil sodium in children following an acute episode of asthma

BACKGROUND

Current guidelines on the treatment of childhood asthma recommend the introduction of an anti-inflammatory drug in children who have persistent symptoms and require regular treatment with a bronchodilator. The efficacy and safety of inhaled nedocromil sodium (Tilade Mint aerosol) administered using a Fisonair spacer at a dose of 4 mg three times daily was compared with placebo in the treatment of asthmatic children aged 6-12 years who are symptomatic and recovering from an acute exacerbation of asthma.

METHODS

A group comparative, double blind, placebo controlled trial was performed in children who were recovering from an acute episode of asthma following treatment in the emergency department of the hospital or in children referred from their general practitioner following a wheezing episode and documented evidence of at least two previous episodes of wheezing. A two week baseline period on existing bronchodilator treatment was followed by a 12 week treatment period on either nedocromil sodium (2 mg/puff) or placebo. Both treatments were administered using a Fisonair spacer at a dose of two puffs three times daily. Changes from baseline values in daytime asthma and night time asthma symptom scores, usage of rescue bronchodilators, mean peak expiratory flow (PEF) recorded twice daily on diary cards, patients' opinion of treatment, and withdrawals due to treatment failure were measured during the primary treatment period (last six weeks of treatment).

RESULTS

One hundred and forty two children aged 6-12 years entered the baseline period. Sixty three were withdrawn due to failure to meet the entry criteria (18) or the criteria for asthma symptom severity (15) or reversibility (9), because they developed uncontrolled asthma (2), because they took disallowed treatment (2), or for other non-trial related reasons (17). Seventy nine patients (46 boys) of mean age 8. 8 years entered the treatment period. There were significant differences in the changes from baseline values during the last six weeks of treatment in favour of nedocromil sodium compared with placebo in the primary variables of daytime asthma and night time asthma, morning and evening PEF, and the usage of rescue inhaled bronchodilators; 53% of patients reported nedocromil sodium to be very or moderately effective compared with 44% placebo. Improvement in asthma symptoms, PEF, and reduction in use of rescue bronchodilators did not reach statistical significance until after six weeks of treatment. Twenty two patients were withdrawn or dropped out during the treatment phase, 12 due to uncontrolled asthma or persistence of asthma symptoms, four due to suspected adverse drug reactions (nedocromil sodium 3 (headaches 2, angio-oedema/urticaria 1), placebo 1(persistent cough)), and six due to non-treatment related reasons. Seventy one adverse events were reported by 27 patients in the nedocromil group and 75 by 30 patients in the placebo group.

CONCLUSIONS

Asthma symptoms, use of bronchodilators, and lung function can be improved significantly in children recovering from an acute exacerbation of asthma or wheeze and currently receiving treatment with bronchodilators alone by the addition of inhaled nedocromil sodium at a dose of 4 mg three times daily administered using a Fisonair holding chamber.