| 1. |
- Bräuner, Elvira Vaclavik, et al.
(författare)
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Indoor particles affect vascular function in the aged: an air filtration-based intervention study.
- 2008
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Ingår i: American journal of respiratory and critical care medicine. - 1535-4970. ; 177:4, s. 419-25
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Tidskriftsartikel (refereegranskat)abstract
- RATIONALE: Exposure to particulate matter is associated with risk of cardiovascular events, possibly through endothelial dysfunction, and indoor air may be most important. OBJECTIVES: We investigated effects of controlled exposure to indoor air particles on microvascular function (MVF) as the primary endpoint and biomarkers of inflammation and oxidative stress as secondary endpoints in a healthy elderly population. METHODS: A total of 21 nonsmoking couples participated in a randomized, double-blind, crossover study with two consecutive 48-hour exposures to either particle-filtered or nonfiltered air (2,533-4,058 and 7,718-12,988 particles/cm(3), respectively) in their homes. MEASUREMENTS AND MAIN RESULTS: MVF was assessed noninvasively by measuring digital peripheral artery tone after arm ischemia. Secondary endpoints included hemoglobin, red blood cells, platelet count, coagulation factors, P-selectin, plasma amyloid A, C-reactive protein, fibrinogen, IL-6, tumor necrosis factor-alpha, protein oxidation measured as 2-aminoadipic semialdehyde in plasma, urinary 8-iso-prostaglandin F(2alpha), and blood pressure. Indoor air filtration significantly improved MVF by 8.1% (95% confidence interval, 0.4-16.3%), and the particulate matter (diameter < 2.5 mum) mass of the indoor particles was more important than the total number concentration (10-700 nm) for these effects. MVF was significantly associated with personal exposure to iron, potassium, copper, zinc, arsenic, and lead in the fine fraction. After Bonferroni correction, none of the secondary biomarkers changed significantly. CONCLUSIONS: Reduction of particle exposure by filtration of recirculated indoor air for only 48 hours improved MVF in healthy elderly citizens, suggesting that this may be a feasible way of reducing the risk of cardiovascular disease.
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| 2. |
- Andersson, Lena, 1980, et al.
(författare)
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Urinary proteins in children with urinary tract infection
- 2009
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Ingår i: Pediatric Nephrology. - : Springer Science and Business Media LLC. - 0931-041X .- 1432-198X. ; 24:8, s. 1533-1538
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Tidskriftsartikel (refereegranskat)abstract
- Abstract The aim of this study was to test our hypothesis that the urinary excretion of C-reactive protein (CRP), alpha 1-microglobulin (A1M), retinol-binding protein (RBP) and Clara cell protein (CC16) is increased in children with urinary tract infection (UTI) and relates to renal damage as measured by acute dimercaptosuccinic acid (DMSA) scintigraphy. Fifty-two children <2 years of age with UTI were enrolled in the study, 44 of whom were febrile. The control group consisted of 23 patients with non-UTI infection and elevated serum CRP (s-CRP) levels. Thirty-six patients had abnormal DMSA uptake, classified as mild, moderate or severe damage (DMSA class 1, 2, 3, respectively). There was a significant association between DMSA class and the excretion of urinary RBP (u-RBP) and u-CC16. There was also a significant difference in u-CRP levels between children with UTI and control children with non-UTI infections, although u-CRP excretion was not significantly correlated to DMSA class. In conclusion, the urinary excretion of the low-molecular-weight proteins RBP and CC16 showed a strong association with uptake defects on renal DMSA scans. The urinary level of CRP seems to distinguish between children with UTI and other febrile conditions. A combination of these biomarkers may be useful in the clinical assessment of children with UTI.
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| 3. |
- Bräuner, Elvira Vaclavik, et al.
(författare)
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Exposure to ambient concentrations of particulate air pollution does not influence vascular function or inflammatory pathways in young healthy individuals.
- 2008
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Ingår i: Particle and fibre toxicology. - : Springer Science and Business Media LLC. - 1743-8977. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT: BACKGROUND: Particulate air pollution is associated with increased risk of cardiovascular events although the involved mechanisms are poorly understood. The objective of the present study was to investigate the effects of controlled exposure to ambient air fine and ultrafine particles on microvascular function and biomarkers related to inflammation, haemostasis and lipid and protein oxidation. METHODS: Twenty-nine subjects participated in a randomized, two-factor crossover study with or without biking exercise for 180 minutes and with 24 hour exposure to particle rich (number concentrations, NC: 11600 +/- 5600 per cm3, mass concentrations: 13.8 +/- 7.4 mug/m3 and 10.5 +/- 4.8 mug/m3 for PM10-2.5 and PM2.5, respectively) or particle filtered (NC: 555 +/- 1053 per cm3) air collected above a busy street. Microvascular function was assessed non-invasively by measuring digital peripheral artery tone following arm ischemia. Biomarkers included haemoglobin, red blood cells, platelet count, coagulation factors, C-reactive protein, fibrinogen, interleukin-6, tumour necrosis factor alpha, lag time to copper-induced oxidation of plasma lipids and protein oxidation measured as 2-aminoadipic semialdehyde in plasma. RESULTS: No statistically significant differences were observed on microvascular function or the biomarkers after exposure to particle rich or particle filtered air. CONCLUSION: This study indicates that exposure to air pollution particles at outdoor concentrations is not associated with detectable systemic inflammation, lipid or protein oxidation, altered haemostasis or microvascular function in young healthy participants.
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| 4. |
- Modig, Lars, 1976-
(författare)
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Asthma, rhinitis, and asthma-related symptoms in relation to vehicle exhaust using different exposure metrics
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Air pollution is a well known public health problem that involves both long-term and acute effects. An outcome associated with traffic-related air pollution is respiratory illness. Many studies have described the relationship between asthmatic symptoms and traffic-related air pollution; however, few have investigated the potential of air pollution to cause asthma itself, especially among adults. The overall aim of this thesis was to study the relationship between vehicle exhaust levels at home and the prevalence of self-reported annoyance and asthmatic symptoms, and the incidence of asthma and rhinitis. These relationships were evaluated using different indicators of exposure with a high spatial resolution. Three different data sets were used for the four papers included in this thesis. The first paper (paper I) is based on a questionnaire that was sent to a random selection of the adult population within three Swedish cities (Gothenburg, Uppsala, and Umeå) as part of the Swedish Environmental Protection Agency’s health-related environmental monitoring. The aim was to study the degree of self-reported annoyance and the prevalence of asthmatic symptoms in relation to the levels of vehicle exhaust outside the home. The level of exposure was described using modeled levels of nitrogen dioxide (NO2) as the exposure indicator. The second paper (paper II) is based on new asthma cases identified within the Obstructive Lung disease In Northern Sweden (OLIN) study, each with a matched referent. The aim of this study was to analyze if new cases of asthma had higher levels of vehicle exhaust outside the home compared to the population controls. Exposure was assessed using both measured levels of NO2 outside each home, and by summarizing the amount of traffic within a 200 metre buffer surrounding each participant’s home. Papers III and IV were based on the Respiratory Health in Northern Europe (RHINE) Cohort, a prospective cohort of adults included in 1990 and followed up with in 1999. The proportion of new cases of asthma (papers III and IV) and rhinitis (paper IV) were identified based on the answers from the initial and follow-up questionnaires. In paper III, exposure was assessed by using meteorological dispersion models to calculate the levels of NO2 outside each home as an indicator of the levels of vehicle exhaust. As an alternative indicator, the distance from each participant’s home to the nearest major road was calculated using geographical information system (GIS) tools. The exposure assessment in paper IV was also based on meteorological dispersion models, but expressed the levels of vehicle exhaust as particle mass concentration. The results show that the levels of vehicle exhaust outside the home are significantly correlated with the degree of self-reported annoyance and the prevalence of asthmatic symptoms, and also with the risk of developing asthma, but not rhinitis, among adults. The odds ratio (OR) for high annoyance to vehicle exhaust and reporting asthmatic symptoms was 1.14 (95% Confidence Interval, CI 1.11-1.18) and 1.04 (95% CI 1.01-1.07) per 1 µg/m3 increase in the NO2 level outside the home, respectively. Paper II showed there was a non-significant tendency for increased risk of developing asthma among those living with high levels of vehicle exhaust outside their home. This finding was then supported by papers III and IV, showing a significant relationship between the onset of asthma and the mean (winter) levels of NO2 outside the home (OR=1.46, 95% CI 1.07-1.99 per 10 µg/m3) and the levels of vehicle exhaust particles outside the home. In paper III, living close to a major road was significantly related to the risk of developing asthma. No significant results were shown between vehicle exhaust and rhinitis. In conclusion, vehicle exhaust outside the home is associated with the prevalence of annoyance and asthmatic symptoms, and with the risk of developing asthma, but not rhinitis, among adults.
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| 5. |
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| 6. |
- Almasri, Abdullah, et al.
(författare)
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A study of residential radon in Sweden using multilevel analysis
- 2008
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Ingår i: Health Physics Journal, to appear 2008.
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Tidskriftsartikel (refereegranskat)abstract
- A Swedish radon data set, consisting of more than 8000 measurements of residential radon levels in about 50% of the Swedish municipalities were analysed using a multilevel approach.The results were compared with those of a single-level analysis. We found that there was a significant variability between municipalities. The point estimates of the population mean radon levels were similar (geometric mean 60 Bq/m3 and arithmetic mean 106 Bq/m3).The analysis shows the advantages of multilevel modeling compared with a single-level OLS model.A single-level model results in too optimistic standard errors, about 25% of those of the multilevelmodel which can lead to erroneous conclusions.In a multilevel model including house type as a fixed effect (single-family house, row house, or apartment in multi-family house), the estimates of the fixed effect of house type were similar for the single-level and the multi-level models
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| 7. |
- Almgren, Sara, 1979, et al.
(författare)
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Gamma radiation doses to people living in Western Sweden.
- 2008
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Ingår i: Journal of environmental radioactivity. - : Elsevier BV. - 0265-931X. ; 99:2, s. 394-403
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Tidskriftsartikel (refereegranskat)abstract
- Indoor environments contribute to gamma radiation in the general population. The aims of the present study were to investigate average gamma radiation doses in a rural and an urban area of Sweden, compare indoor dose rates with personal exposure, and study the effects of building characteristics on radiation levels. Radiation was measured with thermoluminescence dosimeters (TLDs). Repeated measurements were performed with TLDs worn by participants (n=46) and placed in their dwellings. Personal dose rates were 0.092microSv/h (rural) and 0.096microSv/h (urban). The mean effective gamma dose rates in dwellings were 0.091microSv/h (rural) and 0.11microSv/h (urban), which are higher than the world average. Dose rates in apartments were higher than in detached houses and higher for concrete than wooden dwellings. Personal dose rates were strongly associated with dwelling dose rates (r(p)=0.68, p<0.01) and could be modelled. Within-participant variability was low.
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| 8. |
- Almgren, Sara, 1979, et al.
(författare)
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Measurements and comparisons of gamma radiation doses in a high and a low (137)Cs deposition area in Sweden.
- 2008
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Ingår i: Journal of environmental radioactivity. - : Elsevier BV. - 0265-931X. ; 99:11, s. 1750-5
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Tidskriftsartikel (refereegranskat)abstract
- Sweden is one of the countries affected by the Chernobyl fallout. The aim of the present study was to investigate the average radiation dose to people living in a high-deposition area (the parish of Hille) in Sweden for comparison with dose rates previously measured in a low-deposition area in western Sweden. Individual measurements (personal and dwelling dose rates) were performed using thermoluminescence dosimeters in 24 randomly chosen individuals. Dwelling and personal dose rates in Hille were 0.12 and 0.11 microSv/h, respectively. The dose rates in Hille were slightly higher than in western Sweden (difference for detached houses=0.024 microSv/h for personal and 0.030 microSv/h for dwelling dose rates), partly because of the higher (137)Cs deposition. In wooden houses, the difference was somewhat greater. Our results indicate a current contribution to personal gamma radiation in this area of about 0.2 mSv per year from the Chernobyl fallout.
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| 9. |
- Andersson, Lena, et al.
(författare)
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Methodological aspects on measurement of Clara cell protein in urine as a biomarker for airway toxicity, compared with serum levels.
- 2007
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Ingår i: Journal of applied toxicology : JAT. - : Wiley. - 0260-437X .- 1099-1263. ; 27:1, s. 60-6
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Tidskriftsartikel (refereegranskat)abstract
- The Clara cell protein CC16, secreted from Clara cells in the lung, is discussed as a potential biomarker for toxic effects on the airways. An increased concentration of CC16 in serum may be caused by increased permeability of the lungs, caused by high levels of air pollution. Since CC16 is eliminated by renal excretion, it may be possible to use urine instead of serum samples. Few studies have been conducted on urinary CC16 (U-CC16), however.The aim was to investigate the optimal way of sampling and quantifying CC16 in urine samples and compare CC16 in human serum and urinary samples. Repeated sampling was performed in two groups of healthy subjects. First morning urine, 24 h urine, and matched blood and urine samples were collected.The excretion of U-CC16 increased over the day, e.g. from 0.08 microg h(-1) in the morning to 0.28 microg h(-1) in daytime and 0.16 microg h(-1) in the evening (medians in males). Morning samples (microg h(-1)) from males properly reflected the 24 h excretion (r = 0.91). The best correlation with 24 h excretion was obtained with creatinine-corrected first morning urine samples (r > 0.9). Generally, females had lower excretion of CC16 than males (medians 2.5 microg 24 h(-1) in females and 16 microg 24 h(-1) in males). There was significant intraindividual variation, but the interindividual variation was larger in both groups. There was an association between serum CC16 (S-CC16) and U-CC16 in morning samples. With optimal methods for sampling U-CC16, urine samples may be used in experimental studies of air pollution.
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| 10. |
- Andersson, Lena, 1980, et al.
(författare)
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Methodological issues on the use of urinary alpha-1-microglobuline in epidemiological studies.
- 2008
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Ingår i: Nephrology Dialysis Transplantation. - : Oxford University Press (OUP). - 0931-0509 .- 1460-2385. ; 23:4, s. 1252-1256
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Tidskriftsartikel (refereegranskat)abstract
- Background. Alpha-1-microglobulin (A1M) is a low molecular weight protein that can be measured in urine and used as a marker for tubular function, assuming that the normal variability within and between individuals is known. The aims of this study were to investigate this variability, to find the optimal way of sampling and quantifying A1M in spot urine samples to reflect the 24 h excretion and to examine storage stability. Method. Timed urine specimens were collected from 29 healthy volunteers at fixed time points over 24 h on two separate days. Volumes, creatinine and specific gravity were determined. All samples were analysed with a commercial ELISA for A1M. Results. We found a clear diurnal variation in A1M excretion rate and a gender effect (higher in males). The excretion rate was higher in the daytime, with high urinary flow, compared to overnight values. A1M excretion in spot urine samples was highly correlated with the 24 h excretion at all times except 22:00 in male subjects. Urinary A1M adjusted for creatinine concentration correlated well with the 24 h excretion. Variability within individuals was only 20% of the total variability in 24 h A1M excretion, but 43% in first morning urine. Expressed as CV, the intra-individual variability (between days) was 29% in 24 h excretion. Conclusion. We conclude that diurnal variation and gender should be taken into account when comparing groups. Moreover, in spot samples (e.g. first morning samples) adjustment of A1M for creatinine or specific gravity is a reliable alternative to 24 h urine.
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