Physicochemical and structural features of heat treated silver-silica nanocomposite and their impact on biological properties.

In the last few decades, many nanostructures with varying properties and possible applications have been developed. These materials have been intended to work in various environmental temperature conditions. In this context, the main challenge has been to comprehend the impact of synergic interaction between individual elements included in non-annealed materials in relation to systems subjected to temperature impact. Another problem has corresponded to the impact of thermal modification on organisms such as bacteria and human cells. Such problems can be solved by the fabrication of a nanocomposite with mono-dispersed 8 nm silver (Ag0 or Ag+) embedded into a silica carrier, followed by the analysis of the impact of heat treatment under various temperature conditions on its physicochemical features. Therefore, methodical studies reported in this text have shown an increase of silver particle size up to 170 nm, a decrease of its concentration, as well as the formation of sub-nanometer Ag+ and/or Ag2+ clusters as the temperature rises to 1173 K. In turn, the structurally disordered silica carrier had been entirely transformed to cristobalite and tridymite only at 1473 K as well as partial reduction of Ag2+ to Ag+. Simultaneously, inhibition of growth of Gram-positive and Gram-negative bacteria, as well as an increase in cytotoxicity towards human cells was observed as the temperature rose. As a final point, for the first time, a "pseudo" phase diagram of the structural alterations in the Ag/SiO2 nanocomposite has been created, as well as a model of silver-silica transformation to biological systems has been developed.

High activity of the endogenous opioid system and acute but not chronic stress influence experimental colitis development in mice.

Exposition to environmental factors is one of the major underlying causes in inflammatory bowel diseases (IBD), with several endogenous systems involved. Our aim was to characterize the impact of stress on the colitis development in relation to the endogenous opioid system (EOS) activity in mice. A unique mouse model of high and low activity of EOS (namely high (HA)/low (LA) stress-induced analgesia) was employed. Mice were bred using bidirectional selection and classified as HA or LA line based on the measurement of analgesia. Colitis was induced by instillation of trinitrobenzenesulfonic acid in 30% EtOH/0.9% NaCl. After 4 days, the macroscopic score was assessed and samples for molecular and histological studies were collected. To evaluate the influence of stress on colitis development, chronic mild stress (exposure to stress stimuli for 2 and 5 weeks) and acute stress (short restraint over 3 days) were applied before colitis induction. We observed a difference in the colitis development between non-stressed HA and LA mice, as indicated by macroscopic and ulcer scores. Acute stress improved colitis in HA mice but did not change the inflammation score in LA line as compared to respective non-stressed mice. Chronic mild stress had no influence on colitis in either of mouse lines. Our study supports the hypothesis that the activity of EOS may be crucial in IBD development. We also evidence that acute, but not chronic stress influenced IBD exacerbation, depending on EOS function.

An open-label, phase 2, single centre, randomized, crossover design bioequivalence study of AndroForte 5 testosterone cream and Testogel 1% testosterone gel in hypogonadal men: study LP101.

We compared a novel 5% testosterone (T) cream (AndroForte 5, Lawley Pharmaceuticals, Australia) with a 1% T gel (Testogel, Besins Healthcare, Australia). Using an open-label crossover design, subjects were randomized to one of two treatment sequences using either the T gel or T cream first in a 1 : 1 ratio. Each treatment period was 30 days with a 7-14 days washout period between them. On Days 1 and 30 of each treatment period blood was sampled at -15, -5 min, 0, 2, 4, 5, 6, 7, 8, 9, 10, 12 and 16 h post study drug administration. Sixteen men with established androgen deficiency aged between 29 and 73 years, who had undertaken a washout from prior testosterone therapy participated in the study. One subject failed to complete both arms and another was excluded post-completion because of a major protocol violation. Bioequivalence was established based on key pharmacokinetic (PK) variables: AUC, C(avg), C(max), T(max), % fluctuation (with and without baseline correction) for the two formulations of testosterone on Day 1 and Day 30. The ratio and 90% CI of AUC 0.99 (0.86-1.14), C(max) 1.02 (0.84-1.24) and C(avg) 0.99 (0.86-1.14) for T cream/T gel were within the predetermined bio-equivalence criteria of 80% to 125% at Day 30. There were no statistically significant differences between secondary biochemical markers: serum dihydrotestosterone (DHT), oestradiol (E2), sex hormone-binding globulin (SHBG), luteinizing hormone (LH) and (FSH). The two testosterone formulations were shown to be bioequivalent.

The Bosentan Patient Registry: long-term survival in pulmonary arterial hypertension.

BACKGROUND/AIMS: The Bosentan Patient Registry (BPR) was a prospective, multicentre, Australian registry funded by Actelion Pharmaceuticals. The primary aim of the registry was to collect survival data in patients with pulmonary arterial hypertension (PAH) treated with bosentan. METHODS: The BPR was initiated in 15 specialized PAH centres. All patients on or starting bosentan were invited to enrol. Treating physicians notified the registry if patients discontinued bosentan, because of either a change in therapy, transplantation, intervention or death. Survival data were validated against the Australian Institute of Health and Welfare National Death Index. RESULTS: Between 2004 and 2007, a total of 528 patients (mean age 59 ± 17 years) were enrolled representing 69% of patients either previously taking or initiated on bosentan during that time. The BPR population was generally older with more advanced functional deficit than patients enrolled in randomized, placebo-controlled trials. Aetiology was idiopathic (iPAH) in 58% and connective tissue disease related (scleroderma (SSc)-PAH) in 42%. For iPAH patients, World Health Organisation functional classes II, III and IV at enrolment was 8.2%, 66.4% and 20.5%, and for the SSc-PAH cohort, 3.2%, 75.8% and 17.9% respectively. The observed annual mortality was 11.8% in patients with iPAH and 16.6% in patients SSc-PAH. CONCLUSION: This large Australian registry provides 'real life' information on the characteristics and management of PAH in clinical practice. Treatment with bosentan improved survival outcomes in both iPAH and SSc-PAH compared with historical controls. Age, disease severity and aetiology were critical factors in determining clinical outcomes.

A new model to evaluate the long-term cost effectiveness of orphan and highly specialised drugs following listing on the Australian Pharmaceutical Benefits Scheme: the Bosentan Patient Registry.

BACKGROUND: Pharmaceutical subsidy schemes are under increasing pressure to evaluate the cost effectiveness of new highly specialised and orphan drugs for universal subsidy. In the absence of longer-term outcome data, drug sponsors often present modelled data, which can carry a significant level of uncertainty over longer-term projections. Risk-sharing schemes between drug sponsor and government may provide an acceptable method of balancing the uncertainty of longer-term cost effectiveness with the public demand for equitable and timely access to new drugs. METHODS: The Bosentan Patient Registry (BPR) is an example of a unique risk-sharing model utilised in Australia aiming to provide clinical evidence to support the modelled predictions, with the registry survival outcomes linked to future price. Concomitant medication, health and vital status data was collected from clinicians, government health departments and death registries. RESULTS: The BPR has identified a number of issues surrounding registry governance, ethics and patient privacy, and the collection of timely and accurate data, which need to be addressed for the development of a generic registry model for systematic evaluation. CONCLUSION: The success of a generic drug registry model based on the BPR will be enhanced by addressing a number of operational issues identified during the implementation of this project.

Lead dust in broken hill homes--a potential hazard for young children?

OBJECTIVE: To determine the potential hazard posed by indoor lead dust to young children in Broken Hill, a silver-lead-zinc mining town in outback Australia, and the degree to which lead flux is influenced by factors such as geographical location, house construction type and condition. METHODS: 116 homes were selected and 93 (80%) studied from 10 localities in Broken Hill during the spring of 1995. Lead flux was measured using 85 mm diameter polystyrene petri dishes. Dishes were placed in four rooms of each house to collect dust over a six-to-eight-week period. Data on the location, condition and construction type of each house were recorded. Multiple linear regression was used to determine predictors of lead flux. Flux data were log transformed for the analysis. RESULTS: Average household lead flux varied nearly seven-fold across districts from a low of 166 (distant from the mines), to a high of 1,104 microg/m2/30-day period (adjacent to the mines). Houses that were 'adequately sealed' had 2.9 times the lead flux, and 'poorly sealed' houses 4.3 times the flux, of 'very well sealed' houses. Construction material did not significantly affect these flux levels, and no statistically significant interactions were found between house condition and location or house type. CONCLUSIONS: Many Broken Hill homes have high levels of lead flux that pose a potential risk to young children. Quantification of this hazard provides useful information for the community that can help focus efforts on actions required to minimise lead dust in the home. IMPLICATIONS: Household dust is a potential source of lead for young children in at-risk communities. Information on lead flux in homes can assist these communities and public health agencies to better understand and deal more effectively with the problem.

E-cadherin, beta-catenin and stromelysin-3 expression in de novo carcinoma of the colorectum.

An apparent exception to the colorectal adenoma-carcinoma carcinogenic pathway is the so-called "de novo" carcinoma that has no evidence of adenoma in its vicinity. Despite the fact that they are often quite small, these lesions appear to bhe more aggressive (i.e. have greater likelihood of lymph node metastases) than carcinomas that clearly arise from surrounding adenomas ("ex-adenoma carcinoma"). The purpose of the present immunohistochemical study was to compare rates of cell adhesion molecule (E-cadherin and beta-catenin) and protease (stromelysin-3 (ST-3)) expression in groups of de novo (n = 64) and ex-adenoma (n = 42) lesions in order to see if their more aggressive behavior is associated with decreased cell adhesion and increased protease expression. Although beta-catenin expression showed abnormalities (decreased or nuclear expression), it did not differ between the two groups. In contrast, the rates of extensive ST-3 expression and decreased E-cadherin expression were significantly higher in de novo group (P = 0.014 and 0.005, respectively). Histopathologically the de novo group had a significantly higher percentage of case with an infiltrative invasion pattern. These differences highlight the more aggressive phenotype of the de novo colorectal cancer and fit with a greater invasive potential of it.

Pterygium in Australia: a cost of illness study.

PURPOSE: The aim of this report was to describe the number of Australians affected by pterygium in recent years, treatment options, number of treatment encounters and costs of treatment. METHOD: A review of published literature was conducted to identify the prevalence of pterygium in Australian populations. Costs of primary care were based on national general practitioner (GP) survey data. Costs of surgical intervention were based on Health Insurance Commission claims data and Australian Institute of Health and Welfare National Hospital Morbidity Data. RESULTS: Pterygium occurs in 1.1% of Australians. It is more prevalent in populations with higher exposure to ultraviolet radiation, and older men (occurring in 12% of males over 60 years). The estimated annual number of GP contacts was 58,900. Forty per cent of primary care contacts for pterygium were referred to an ophthalmologist and topical medication was prescribed by GPs in 32% of contacts. The estimated annual cost of GP visits, specialist visits and topical medication was AUD$3.2 m. There were 6997 claims for pterygium removal in 1999/2000 with 3192 conjunctival autografts. Rates of pterygium removal were highest in Queensland with 56 per 100,000 population. The annual costs of surgical intervention were estimated at AUD$4.8 m. CONCLUSIONS: The direct medical costs of pterygium in Australia are AUD$8.3 m annually. This is likely to be an underestimate of total cost because indirect costs such as loss of work time could not be measured. More data are needed on the long-term benefits of pterygium intervention.

A comparative study of E-cadherin and stromelysin-3 expression in de novo and ex adenoma carcinoma of the colorectum.

An apparent exception to the colorectal adenoma-carcinoma carcinogenetic pathway is the so-called "de novo" carcinoma which has no evidence of adenoma in its vicinity. Despite the fact that they are often quite small, these lesions appear to be more aggressive (i.e., greater likelihood of lymph-node metastases) than carcinomas that clearly arise from surrounding adenomas exadenoma carcinoma. The purpose of the present comparative immunohistochemical study was to compare rates of cell adhesion molecule (E-cadherin) and protease [stromelysin-3 (ST-3)] expression in groups of de novo (n=64) and ex adenoma (n=42) lesions in order to see whether their more aggressive behavior is associated with decreased cell adhesion and increased protease expression. The rates of extensive ST-3 expression and decreased E-cadherin expression were significantly higher in the de novo group (P=0.014 and 0.005, respectively). Histopathologically, the de novo group also had a significantly higher percentage of cases with an infiltrative invasion pattern. These differences highlight the more aggressive phenotype of the de novo colorectal carcinoma and fit with their greater invasive potential.

Serological evidence of infection with Chlamydia pneumoniae is related to the severity of asthma.

There is evidence that infection with Chlamydia pneumoniae is associated with asthma of recent onset and that it can influence the severity of asthma. This has led to the suggestion that macrolide antibiotics may be useful in the treatment of asthma in subjects infected with C. pneumoniae. This study examined the association between immunoglobulin (Ig)G and IgA titres to C. pneumoniae and the severity of asthma. IgG and IgA antibodies to C. pneumoniae were measured in 619 subjects with asthma (18-60 yrs), using the microimmunofluoresence method. Subjects were asked about their use of asthma medicines, symptoms, previous hospitalization for asthma, smoking status and age of onset of asthma. In subjects with IgG titres of > or =1:64 and/or IgA titres > or =1:16 (n=212), spirometry was performed and peak expiratory flow rate (PEFR) and symptoms were recorded twice daily for 4 weeks on a diary card. The use of high dose inhaled steroids was associated with an increase of 74.1% in the titre of IgG antibodies (p=0.04) and an increase of 70.6% in the titre of IgA antibodies (p=0.0001) when compared with the use of low dose inhaled steroids. There was an inverse association between IgG antibodies and forced expiratory volume in one second (FEV1) as a percentage of predicted in those subjects with elevated IgG and/or IgA (p=0.04). In this group IgA antibodies were also associated with a higher daytime symptom score (p=0.04). Higher titres of antibodies to Chlamydia pneumoniae appears to be associated with markers of asthma severity. This raises the possibility that chronic infection with Chlamydia pneumoniae leads to an increase in the severity of asthma. Studies aimed at eradicating chronic infection with Chlamydia pneumoniae are necessary to determine whether or not this is the case.

Comparison of family history measures used to identify high risk of coronary heart disease.

We examined 15 published continuous family history measures (scores) as well as two new formulations in terms of several desirable properties. We applied the scores to sample pedigrees and found that some systematically increase with family size. In contrast to aggregate scores, non-aggregate scores are sensitive to the age, sex, and covariate status of individual relatives but are unstable when the families are small. We also applied these scores to our own population case-control data, characterised by a high proportion of missing and false-negative responses. In these small families, all scores provided significant discrimination between CHD cases and controls beyond the usual categorical definition of positive family history, but appeared no better than detailed categorical definitions or even simple counts. Our new formulations offer no solution to the problems of few data; most scores apply asymptotic approximations to differences between observed and expected number of affected relatives and are not suited to small families. All scores would be improved by ruling out families with only one affected relative, as is being done in the NHLBI Family Heart Study. We recommend that researchers, when using a family history measure, consider the number of informative families and other characteristics of their data prior to choosing any particular formulation.

Air pollution and hospital admissions in Sydney, Australia, 1990 to 1994.

OBJECTIVES: This study examined the effects of outdoor air pollutants on daily hospital admissions in Sydney, Australia. METHODS: A time-series analysis of counts of daily hospital admissions and outdoor air pollutants (1990 to 1994) was performed, by means of Poisson regression that allowed for overdispersion and autocorrelation. RESULTS: An increase in daily maximum 1-hour concentration of nitrogen dioxide from the 10th to the 90th percentile was associated with an increase of 5.29% (95% confidence interval = 1.07, 9.68) in childhood asthma admissions and 4.60%(-0.17,9.61) in chronic obstructive pulmonary disease (COPD) admissions. A similar increase in daily maximum 1-hour particulate concentration was associated with an increase of 3.01% (-0.38, 6.52) in COPD admissions. An increase from the 10th to the 90th percentile in daily maximum 1-hour nitrogen dioxide, daily maximum 1-hour ozone, and daily mean particulate was associated with an increase in heart disease admissions among those 65 years and older of 6.71% (4.25, 9.23), 2.45% (-0.37, 5.35), and 2.82% (0.90, 4.77), respectively. Heart disease and childhood asthma were primarily associated with nitrogen dioxide; COPD was associated with both nitrogen dioxide and particulates. CONCLUSIONS: Current levels of air pollution in Sydney are associated with increased hospitalization for respiratory and heart disease.

Outdoor air pollution and children's respiratory symptoms in the steel cities of New South Wales.

OBJECTIVE: To investigate the relationship between outdoor air pollution and the respiratory health of children aged 8 to 10 years. DESIGN: A cross-sectional survey (between October 1993 and December 1993) of children's health and home environment. Summary measures of particulate pollution (levels of particles with an aerodynamic diameter less than 10 microns [PM10] each 6th day) and SO2 (daily mean and maximum hourly values) were estimated for each area (using air quality monitoring station data from July 1993 to June 1994). SETTING AND SURVEY PARTICIPANTS: Parents of 3023 primary school children (Years 3, 4 and 5) from industrial and non-industrial areas with air quality monitoring stations in the Hunter and Illawarra regions of New South Wales. MAIN OUTCOME MEASURES: Reported occurrence of four or more chest colds, four or more attacks of wheezing, and night-time cough without a cold for more than two weeks, all within the previous 12 months. RESULTS: 77% response rate, ranging by area from 66% to 88%. The average annual outdoor air pollution for the nine areas was 18.6-43.7 micrograms/m3 for PM10 and 0.16-0.90 parts per hundred million for SO2. The proportion of children reported to have the main outcome symptoms were: chest colds, 3.0%-9.7%; night cough, 12.3%-30.5%; and wheeze, 3.4%-11.3%. There was no significant association with SO2, but a significant increase in the odds of symptoms per 10 micrograms/m3 increase in PM10 on chest colds (odds ratio [OR], 1.43; 95% confidence interval [CI], 1.12-1.82) and night-time cough (OR, 1.34; 95% CI, 1.19-1.53), but not wheeze. Passive smoking was significantly associated with chest colds but not with the other symptoms. Maternal allergy was associated with all three respiratory symptoms, most strongly with wheeze. CONCLUSION: These results provide evidence of health effects at lower than expected levels of outdoor air pollution in the Australian setting. They also suggest differences in contributions of environmental and hereditary factors to cough and chest colds compared with wheeze.

Epidemiological association of airway inflammation with asthma symptoms and airway hyperresponsiveness in childhood.

The role of airway inflammation in childhood asthma is not well defined, despite modern treatment approaches recommending potent anti-inflammatory therapy for an increasing number of children. In this study, induced sputum analysis was used to investigate the relationships among sputum inflammatory cells (eosinophils and mast cells), asthma symptoms, and airway hyperresponsiveness to hypertonic saline in a cohort of 170 children aged 8-14 years. Children who reported asthma symptoms in the past 2 wk had a 2. 25-fold (95% to CI, 1.20-4.24) increased odds of having significant sputum eosinophilia. Hyperresponsiveness to hypertonic saline was strongly associated with higher levels of sputum eosinophils ([OR] 4. 36, 1.70-11.20), sputum mast cells (OR 7.46, 2.48-22.75), and nasal eosinophils (OR 4.73, 1.89-11.86). Interestingly, boys were more likely than girls to have features of airway inflammation (sputum mast cells, OR 3.33, 1.15-9.65; nasal eosinophils, OR 3.25, 1.72-5. 97), which is consistent with the known increase in asthma prevalence in boys in this age group. Airway inflammation with eosinophils and mast cells is likely to be important in the pathogenesis of asthma in childhood. Induced sputum analysis can be used to evaluate this problem and has the potential to be a useful tool for monitoring therapy.

Correction for biases in a population-based study of family history and coronary heart disease. The Newcastle Family History Study I.

In this paper, the authors report on the design of a population-based case-control study of family history as a risk factor for coronary heart disease (CHD). They studied the characteristics of subjects who completed a detailed family history questionnaire in 1992-1994 as well as the accuracy of recall of family history in order to quantify both selection and recall biases. Coronary disease cases were enrolled through the Newcastle MONICA Project (Monitoring Trends and Determinants in Cardiovascular Disease), which registered all suspected heart attacks and sudden cardiac deaths in the Lower Hunter region of New South Wales, Australia, between August 1984 and March 1994. Controls were selected at random from the New South Wales electoral roll. The response rate was 76% in cases and 62% in controls; the major factor associated with participation in the study was perceived family history of CHD, more so in the control series than in the case series. Accuracy was determined by comparing information obtained from the proband with that recorded on death certificates. In first-degree relatives, sensitivity of CHD recall was 85% (95% confidence interval (CI) 74-92%) in cases and 95% (95% CI 84-99%) in controls, while specificity was 59% (95% CI 49-69%) and 74% (95% CI 65-82%), respectively. The net bias in both selection and recall is toward the null and hence the comparisons provide a conservative estimate of risk of CHD associated with a positive family history.

Risk associated with various definitions of family history of coronary heart disease. The Newcastle Family History Study II.

The authors carried out a population-based case-control study to estimate the risk of an acute coronary disease event associated with various definitions of a family history of coronary heart disease (CHD). A detailed family history questionnaire was completed by 403 cases and 236 controls in Newcastle, New South Wales, Australia from 1992 to 1994. Odds ratios of an acute coronary disease event adjusted for proband age and sex ranged from 2.7 (95% confidence interval (CI) 1.8-4.1) for the simplest definition (one or more first-degree relatives with CHD at any age) to 5.4 (95% CI 1.7-16.8) for the most stringent definition (two or more first-degree relatives with CHD before age 55 years). In a series of nested models, the authors examined the improvement in model fit as each component of the detailed family history was added. Additional information was provided by accounting for "don't know" responses, the number of affected relatives, the age of the affected relative, and whether the first-degree relative was a sibling rather than a parent. The results were similar when the data were analyzed as a cohort design with proband disease status as the exposure variable. The authors suggest that, to facilitate preventive efforts in a population, more detailed family history definitions should be used to better target high risk subjects.

Severe exacerbation of chronic obstructive airways disease: health resource use in general practice and hospital.

The objective of this study is to examine the treatment of exacerbations of chronic obstructive airways disease (COAD) in the hospital and in the community setting using a retrospective study of patients admitted to a major teaching hospital combined with a general practice chart audit. The admission records for 248 admissions from 128 patients were reviewed. Most patients (70%) had visited their GP within 2 weeks of admission, antibiotics were prescribed for 30% of the exacerbations while 51% were treated with ingested corticosteroids. During hospitalization, features of infection were present in 64% (n = 159) of exacerbations and 79% (n = 196) received antibiotics. Patients were also treated with nebulized bronchodilators, oxygen and corticosteroids (82%). The median length of stay was 10 days (range 0-55). There was a high readmission rate (70%) at 1 year for exacerbation of COAD during the study period. Exacerbations of COAD frequently demonstrated the clinical features of infection. Treatment in general practice was less intensive than in hospital, and there is a need to reconcile these differences with studies of early therapy with antibiotics and corticosteroids. Although corticosteroids were used less often in general practice, the literature in this area is not conclusive and the evidence supporting guideline recommendations is not explicit. There are opportunities to examine the role of early therapy and early discharge programmes to minimize the cost burden from exacerbations of COAD.

A double-blind randomized clinical trial on the effectiveness of a daily glycolic acid 5% formulation in the treatment of photoaging.

BACKGROUND: Low-strength daily formulations of glycolic acid are widely promoted for the treatment of photoaging. However, there are few clinical studies that objectively confirm the benefits of such formulations. OBJECTIVE: The purpose of this study was to determine the effectiveness of a 5% unneutralized formulation of glycolic acid in the treatment of facial and neck photoaging. METHODS: Seventy-five volunteers were recruited to take part in this double-blind randomized placebo-controlled clinical study. Participants applied either the 5% glycolic acid cream or the placebo cream to the face and neck for a period of 3 months. Pre- and posttreatment clinical assessments of photoaging effects were made by the same physician and were analyzed for statistical significance. RESULTS: Overall there were trends towards greater improvement or less worsening in the glycolic acid group for all clinical assessments for photoaging. There was statistically significant improvement favoring the active-cream in general skin texture and discoloration. There was a trend favoring glycolic acid in reduction of wrinkles, but this did not achieve statistical significance. CONCLUSION: Unneutralized 5% glycolic acid topical cream when used on a regular daily basis can improve some photoaging effects.

Air pollution and daily mortality in Sydney, Australia, 1989 through 1993.

OBJECTIVES: This study examined the effects of outdoor air pollutants in Sydney, Australia, on daily mortality. METHODS: Time-series analysis was performed on counts of daily mortality and major outdoor air pollutants (particulates, ozone, and nitrogen dioxide) in Sydney (1989 to 1993) with adjustment for seasonal and cyclical factors. Poisson regression was calculated with allowance for overdispersion and autocorrelation. The effects of lagging exposure by 0 to 2 days were assessed with single- and multiple-pollutant models. RESULTS: An increase in daily mean particulate concentration from the 10th to the 90th centile was associated with an increase of 2.63% (95% confidence interval 0.87 to 4.41) in all-cause mortality and 2.68% (0.25 to 5.16) in cardiovascular mortality. An increase in daily maximum 1-hour ozone concentration from the 10th to the 90th centile was associated with an increase of 2.04% (0.37 to 3.73) in all-cause mortality and 2.52% (-0.25 to 5.38) in cardiovascular mortality. An increase in the daily mean nitrogen dioxide concentration from the 10th to the 90th centile was associated with an increase of 7.71% (-0.34 to 16.40) in respiratory mortality. Multiple-pollutant models suggest that the effects of particulates and ozone on all-cause and cardiovascular mortality, and of nitrogen dioxide on respiratory mortality, are independent of the effects of the other pollutants. CONCLUSIONS: Current levels of air pollution in Sydney are associated with daily mortality.

PIP: The effects of outdoor air pollutants on mortality in Sydney, Australia, are examined over the period 1989-1993 using a time-series analysis. The results show a clear relation between levels of air pollution and all-cause, cardiovascular, and respiratory mortality.