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An approach to investigating the importance of high potency polycyclic aromatic hydrocarbons (PAHs) in the induction of lung cancer by air pollution.

Evidence suggests that people living in urban areas have an increased risk of lung cancer due to higher levels of air pollution in these areas. Benzo[a]pyrene (B[a]P) is currently used as the main indicator of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in air pollution, but there is concern that B[a]P may not be the ideal surrogate of choice for PAH mixtures since higher potency PAHs have recently been identified which could potentially contribute more and variably to the overall carcinogenicity. Dibenzo[a,h]anthracene (DBA) and dibenzo[a,l]pyrene (DB[a,l]P) are estimated to have carcinogenic potencies 10 or more times greater than B[a]P but data on their presence and formation in the environment are limited. Several occupational and environmental PAH biomonitoring studies are reviewed here, with particular focus on the specific exposure groups, study design, sample tissue, in particular the use of nasal tissues, and biomarkers used in each study. Consideration of these data is then used to propose a novel biomonitoring approach to evaluate exposure, uptake and the role of high potency PAHs in air pollution-related lung cancer. This is based upon an occupational study examining specific DNA adducts for DBA and DB[a,l]P in nasal cells to evaluate the extent to which these high potency PAHs might contribute to the increased risk of developing lung cancer from air pollution.

Air↗

Bone mineral density in relation to body mass index among young women: a prospective cohort study.

AIM: To identify important predictors among lifestyle behaviours and physiological factors of bone mineral density (BMD) in relation to body mass index (BMI) among young women over a 2-year period. DESIGN, SAMPLE AND MEASUREMENTS: Data were collected in 1999 and 2001. Healthy young women (n=152) completed a questionnaire. BMD measurements were performed by DEXA in the calcaneus. The women were subdivided into three categories according to baseline BMI. RESULTS: Baseline bodyweight explained 25% of the variability in BMD at follow-up in the BMI<19 category, and high physical activity seemed to hinder BMD development. In the BMI>24 category, a difference in time spent outdoors during winter between baseline and follow-up was the single most important factor for BMD levels. Overweight women with periods of amenorrhoea had lower BMD than overweight women without such periods. CONCLUSIONS: Predictors and lifestyle behaviours associated with BMD are likely to be based on women of normal weight. BMI should be considered when advising on physical activity, since high physical activity seems to impair BMD development among underweight young women, possibly due to energy imbalance. Among overweight women, sleep satisfaction is the greatest predictor associated with BMD change and may indicate better bone formation conditions. Energy balance and sleep quality may be prerequisites of bone health and should be considered in prevention.

Absorptiometry, Photon↗

Is the introduction of a student-centred, problem-based curriculum associated with improvements in student nurse well-being and performance? An observational study of effect.

AIMS: To explore the impact of curriculum redesign and innovation on student well-being and performance, including essay and examination marks and sickness absence. BACKGROUND: While the emotional impact of preparing to be a health professional can be reduced by helping students to adapt, the positive effect of curriculum innovation and redesign is rarely evaluated. DESIGN, SAMPLE AND METHODS: Student nurse well-being and performance was compared at weeks 24/25 and 40/50 following course entry between comparable independent cohorts of students undertaking a traditional programme (N=406, 83% return rate) with those on an innovative, student-centred, problem-based educational programme (N=447, 79% return rate). The setting was a School of Nursing and Midwifery in the North-East of Scotland. Measures included stress and mental health outcomes and measures of performance including academic marks and sickness absence. RESULTS: At week 25 into the course students on the innovative course had fewer academic, clinical and personal worries than students in the previous more traditional programme and were more likely to report using adaptive direct, problem-solving coping at week 50. While students on the innovative course reported less distress in their first year of the course, they scored less well on comparable essay assignments and had reliably greater sickness absence totals than those educated by traditional methods. CONCLUSION: In this setting, curriculum innovation was associated with positive changes in student well-being but not on performance.

Absenteeism↗

Intervention Without Borders - an Automated Self-Guided AI-Enhanced Psychoeducation Intervention for Dementia Caregivers: Parallel-Group Randomized Waitlist-Controlled Trial.

OBJECTIVE: To examine whether a fully automated, self-guided intervention (PDC30) could improve caregiver well-being over a 1-month waitlist control in an international sample. DESIGN: Randomized waitlist-controlled trial. SETTING: Web-based platform accessible globally. PARTICIPANTS: 441 individuals responded to study promotion on the internet, of whom 274 from 43 countries met the study criteria and were randomized. Eligible participants were adults providing &#x2265;10 care hours weekly to community-dwelling relatives with dementia, scoring &#x2265;5 on Patient Health Questionnaire-9 (PHQ-9), and without recent caregiver intervention. INTERVENTION: Available 24/7, PDC30 is a self-guided, automated intervention consisting of a Guidebook, an AI-powered counseling chatbot, and interactive applications for cognitive-behavioral techniques, relaxation, and caregiver-recipient bonding. MEASUREMENTS: At baseline and follow-ups at 1, 2, and 3 months, depression was assessed by PHQ-9. Secondary outcomes were measured with validated brief versions of anxiety, burden, and positive gains. RESULTS: Intent-to-treat analysis using mixed-effects regression showed treatment x time2 effects on all outcomes except anxiety. At 1-month follow-up, coinciding with exclusive access to PDC30, intervention caregivers showed significant improvements in depression (d = -0.37), burden (d = -0.34), and positive gains (d = 0.42). The differences mostly disappeared after control participants received the intervention, while improvements in both groups were sustained thereafter. Participants reported using the website several times weekly, were generally satisfied with it, and found the chatbot most helpful. CONCLUSIONS: The effects on depression and other outcomes were consistent with those observed for in-person programs, suggesting the viability of well-designed automated intervention. The study demonstrates the feasibility, acceptability, and potential global health impact of PDC30.

Humans↗

Methodological improvements of pyrosequencing technology.

Pyrosequencing technology is a rather novel DNA sequencing method based on the sequencing-by-synthesis principle. This bioluminometric, real-time DNA sequencing technique employs a cascade of four enzymatic reactions producing sequence peak signals. The method has been proven highly suitable for single nucleotide polymorphism analysis and sequencing of short stretches of DNA. Although the pyrosequencing procedure is relatively straightforward, users may face challenges due to varying parameters in PCR and sequencing primer design, sample preparation and nucleotide dispensation; such challenges are labor and cost intensive. In this study, these issues have been addressed to increase signal quality and assure sequence accuracy.

Base Sequence↗

Ante mortem diagnosis of human rabies using saliva samples: comparison of real time and conventional RT-PCR techniques.

BACKGROUND: Rabies is an enzootic and fatal disease and is still a major problem in developing countries. Ante mortem diagnosis in human cases is necessary for medical management of the patient and to ensure appropriate post-exposure treatment of contacts. Both conventional RT-PCR and Real time PCR (TaqMan) have been described for the detection of rabies virus RNA from saliva and tissue respectively, however to date, there have been no studies comparing conventional and real time PCR assays for detection of rabies virus nucleic acid using saliva samples for ante mortem diagnosis. OBJECTIVES: In this study, we evaluated the utility of conventional RT-PCR and SYBR Green I Real time PCR in the ante mortem diagnosis of rabies using saliva samples. STUDY DESIGN: Saliva samples collected from twenty-four patients presenting with typical clinical manifestations of rabies were tested in the two assays. RESULTS: Amongst the 24 samples tested, 21 samples (87.5%) were positive by either of the two molecular methods. Of these 21, rabies virus RNA was detected in 6/21 in the conventional RT-PCR assay while SYBR Green I Real time PCR could detect RNA in 18/21 samples. CONCLUSION: Real time PCR assay was more sensitive than conventional RT-PCR assay (sensitivity 75% versus 37%, p=0.0189). This study highlights the utility of molecular diagnostic tests in establishing ante mortem diagnosis of rabies using saliva samples within a few hours.

Adolescent↗

Third molars associated with periodontal pathology in the Third National Health and Nutrition Examination Survey.

PURPOSE: Assess the association between visible third molars (VTM) and periodontal pathology in Third National Health and Nutrition Examination Survey (NHANES III). MATERIALS AND METHODS: Data were obtained on 5,831 persons aged 18 to 34 from the NHANES III. Relevant to the present study was the presence of VTM and the assessment of periodontal disease in 2 randomly selected (1 maxillary and 1 mandibular) quadrants. Periodontal measures included gingival index, pocket depth, and attachment level on mesiobuccal and buccal sites on up to 7 teeth (excluding third molars) per quadrant. Second molars were compared for periodontal pathology based on the presence or absence of a VTM in the same quadrant. Associations were determined using odds ratios and 95% confidence intervals. Weighted multivariable models were fit using logistic regression, and variances were adjusted to account for the complex sampling design using SUDAAN (Research Triangle Institute, Research Triangle Park, NC). RESULTS: A VTM was associated with twice the odds of a probing depth 5+ mm (PD5+) on the adjacent second molar, while controlling for other factors associated with VTM and periodontal disease. Other factors positively associated with PD5+ in the model were age 25 to 34 years, smoking, and African American race. CONCLUSIONS: The finding of more severe periodontal conditions associated with VTM in these young adults indicates that third molars may have a negative impact on periodontal health. The relationship between third molars and periodontal disease pathogenesis deserves further study using longitudinal data.

Adolescent↗

Psychosocial effects of hysterectomy: literature review.

OBJECTIVES: With the development of less invasive treatments, the suitability of hysterectomy as a treatment for benign symptoms is being reevaluated. This paper critically and comprehensively reviews the psychosocial outcomes of hysterectomy in areas of sexuality, pain, and psychological functioning. METHODS: Medline, Pub Med, and PsychLit were searched for studies and reviews pertaining to the psychosocial outcomes of hysterectomy. Over 100 studies and reviews, in English, French, and German language, published in the past 30 years were included. Controversial theories and empirical evidence are discussed in the domains of sexuality, pain, and psychological well-being. Special attention is devoted to design, sampling, and measurement issues as well as different surgical approaches with regard to hysterectomy-oophorectomy. RESULTS: While hysterectomy appears to reduce pain, there do not appear strong psychosexual or psychosocial effects. Nonetheless, there may be a subgroup of women (10-20%) who report negative psychosocial outcomes such as reduced sexual interest, arousal, and orgasm, as well as elevated depressive symptoms and impaired body image. CONCLUSIONS: More research is necessary to establish which patients may benefit most and which may not. Directions for future research are discussed.

Adult↗

Exploratory data analysis of the Mediterranean component of the BEEP programme.

Work Package 3 (WP3) uses the data generated by ecotoxicologists from 11 laboratories who sample twice per year at four sites (France, Italy, Spain and Greece) to conduct the Mediterranean portion of the BEEP programme (Biological Effects of Environmental Pollution in marine coastal ecosystems). The WP3 data have been compiled into files using a data base structure (one record=one measurement) that eases statistical analysis and importation of new data. Here we present our first attempt of exploratory analysis based on a subset of data from the campaigns in May and September of 2001 and 2002. For most biomarkers, data plot revealed a strong station*campaign interaction, confirmed by two-way ANOVAs. This could be "true" variability with biomarkers responding to contaminant inputs that have changed among the four sampling times. Alternatively it could betray analytical problems and inadequate sampling designs or a lack of stability in the biomarkers themselves whereby they change in random ways unrelated to environmental factors.

Acetylcholinesterase↗

Marine sediment contamination of an industrial site at Port of Bagnoli, Gulf of Naples, Southern Italy.

For almost one century an important steel plant has been active at the Bagnoli industrial area (Naples, Southern Italy). The environmental survey of near shore and offshore sediments has been carried out as fundamental part of a clean up project. The characteristics of the area, supposed type of pollution, national and international protocols in force were taken into consideration in designing sampling schemes and selecting analytical parameters. For this work, sediment grain size, PAHs, PCBs, trace elements, total hydrocarbons and organic matter were considered. Factor analysis evidenced two main types of pollution in the proximity of the industrial plant, both probably attributable to the activity of the industrial site. The first one, due to Cd, Pb, Zn and Mn seems determined by localised activities at the southern part of the plant. The second one, due to Fe and Mn, appears directly linked to the whole contaminated area.

Environmental Monitoring↗

Phosphorus dynamics in water and sediments in urbanized and non-urbanized rivers in Southern Brazil.

Phosphorus flux models show that the removal tends to be a common feature in polluted estuarine systems whereas the release of P to the adjacent coastal area occurs in pristine environments. This study analyzes the distribution of P in water and sediments along six rivers in the south coast of Brazil. Three rivers located inside protected areas were considered non-polluted and used as a control of urbanization. The other three, situated within urbanized areas, were considered as having highly elevated concentrations of P. Results showed a different behavior of P in water and sediments located in urbanized and non-urbanized areas. The concentrations of dissolved organic (P-org) and inorganic (P-inorg) phosphorus in water, and the total phosphorus (P-tot) and polyphosphate (P-poly) in sediments where higher in the urbanized rivers compared to the non-urbanized ones. Both P of punctual origin and of diffuse origin contributed to the maintenance of elevated concentrations and disturbed the natural fluxes along the polluted rivers. The minimum and maximum concentrations in urbanized areas varied from 0.39 to 12.45 (microM) for P-org and 0.00 to 5.92 (microM) for P-inorg in water, and in sediments from 89.90 to 808.16 (microM g(-1)) for P-tot and 0.00 to 76.51 (microM g(-1)) for P-poly. In non-urbanized areas concentrations in water varied from 0.22 to 1.20 (microM) for P-inorg and 4.43 to 5.56 (microM) for P-org, and in sediments from 45.91 to 652.26 (microM g(-1)) for P-tot and 0.00 to 8.61 (microM g(-1)) for P-poly. Using a hierarchical sampling design and a simple model of variation of P (K(d) model) it was possible to demonstrate that urbanized and non-urbanized estuaries may act as sinks or sources of P. The variation of P analysis in different points along each of the six rivers showed that release and removal areas may occur within a same river independently of its urbanization.

Brazil↗

Nitrogen isotope ratios in estuarine biota collected along a nutrient gradient in Narragansett Bay, Rhode Island, USA.

Stable nitrogen isotope ratios were used to study the incorporation of anthropogenically-derived nitrogen into the food webs of salt marsh systems along a contamination gradient in Narragansett Bay. Nitrogen isotope ratios (delta(15)N) were measured in six estuarine species collected from three marshes along this gradient, monthly from June to October between 1997 and 1999. A significant decrease in delta(15)N was found with distance along the estuary for four of the six species. Significant differences were found among monthly isotope ratios for some species. Nitrogen isotope ratios in sea lettuce (Ulva lactuca) increased during the summer season with highest delta(15)N values measured during September and October. This trend was most pronounced at the station receiving the highest nutrient inputs. Elevated delta(15)N values at this station appeared to correlate with seawater ammonia/nitrate concentration ratios. The temporal variations in delta(15)N suggest that care should be taken in species selection and the design of sampling schemes of studies using delta(15)N for monitoring anthropogenic nutrients in aquatic systems. Sampling programs designed to determine long-term trends should consider species that do not show rapid fluctuations in isotope ratios. The mud snail, Nassarius obsoletus, responded this way in the present study. Studies designed to measure short-term changes should include species such as U. lactuca, which rapidly respond to isotope changes. The results from this study also help to establish a baseline for nitrogen isotope values in Narragansett Bay. This information can be used to monitor future trends in nitrogen inputs to this estuary.

Animals↗

Distribution patterns of macrobenthic species in relation to organic enrichment within aquaculture earthen ponds.

The relationship between organic enrichment and macrobenthic colonization patterns was investigated during an 8-month period in Diplodus sargus (white seabream) production ponds. A stratified sampling design was applied and each pond was divided into three zones: water entrance (WE); central (C); and automatic feeder zones (AF). Generally, the number of species and Shannon-Wiener diversity increased from the WE to the AF zone. Abundance did not present a clear trend. The recently developed marine biotic index (AMBI) was applied and showed to be sufficiently robust to discriminate, within a relatively small area, differences in macrobenthic communities due to organic enrichment. Nevertheless, caution is advised when applying this index or others based on ecological group's assignment, as the classification of a certain area may differ when allocating a certain species to an unsuitable group. This is particularly evident when common species are involved.

Animals↗

Using GIS-based approaches to support research on neurotoxicants and other children's environmental health threats.

Environmental threats to children's health are complex and multifaceted; consequently, children's environmental health research strives to identify areas of elevated exposure, determine whether particular demographic groups are inequitably exposed, and link exposures to incidence of disease. Many environmental health researchers use geographic information systems (GIS) to ex post display the results of their data collection and analysis. This methodological paper shows some ways by which the ex ante integration of GIS into environmental exposure and epidemiological research can significantly enhance: research design; sampling, recruitment, and retention strategies; data management and analysis; and community translation.

Child↗

Changes in health behaviors among older Americans, 1990 to 2000.

OBJECTIVES: The authors used a large population-based survey to examine changes from 1990 to 2000 in age distribution by sex and race or ethnicity, to estimate both state-specific and national trends in the proportion of older Americans, and to examine changes in risk factors and quality-of-life indicators among those Americans. METHODS: The Behavioral Risk Factor Surveillance System (BRFSS), a cross-sectional telephone survey of adults aged > or =18 years. BRFSS data were analyzed for the District of Columbia and all states that participated from 1990 to 2000. SAS and SUDAAN were used in the analyses to account for the complex sampling design. RESULTS: The percentage of Americans aged > or =75 years increased 23.0% from 1990 to 2000, with the magnitude of the increase varying by state. In 2000, Florida had the highest percentage of persons aged > or =75 (10.27%) and Alaska the lowest (3.49%). Compared with 1990, older Americans in 2000 were more likely to be obese (16.3% vs. 13.5%) or diabetic (14.3% vs. 11.0%). Older Americans in 2000 were also more likely to exercise, consume more fruits and vegetables daily, and to have recently obtained a routine medical checkup. In addition, they were less likely to smoke tobacco or drink any alcohol. CONCLUSIONS: Increases in the population of older people will have a tremendous impact on health care in the states and will affect their future plans for serving the elderly. Although older Americans are living more healthfully than previously, there is an enormous need for targeted health promotion programs to prevent chronic diseases in this age group.

Aged↗

Factors associated with underimmunization at 3 months of age in four medically underserved areas.

OBJECTIVE: Risk factors for underimmunization at 3 months of age are not well described. This study examines coverage rates and factors associated with under-immunization at 3 months of age in four medically underserved areas. METHODS: During 1997-1998, cross-sectional household surveys using a two-stage cluster sample design were conducted in four federally designated Health Professional Shortage Areas. Respondents were parents or caregivers of children ages 12-35 months: 847 from northern Manhattan, 843 from Detroit, 771 from San Diego, and 1,091 from rural Colorado. A child was considered up-to-date (UTD) with vaccinations at 3 months of age if documentation of receipt of diphtheria-tetanus-pertussis, polio, haemophilus influenzae type B, and hepatitis B vaccines was obtained from a provider or a hand-held vaccination card, or both. RESULTS: Household response rates ranged from 79% to 88% across sites. Vaccination coverage levels at 3 months of age varied across sites: 82.4% in northern Manhattan, 70.5% in Detroit, 82.3% in San Diego, and 75.8% in rural Colorado. Among children who were not UTD, the majority (65.7% to 71.5% per site) had missed vaccines due to missed opportunities. Factors associated with not being UTD varied by site and included having public or no insurance, >/=2 children living in the household, and the adult respondent being unmarried. At all sites, vaccination coverage among WIC enrollees was higher than coverage among children eligible for but not enrolled in WIC, but the association between UTD status and WIC enrollment was statistically significant for only one site and marginally significant for two other sites. CONCLUSIONS: Missed opportunities were a significant barrier to vaccinations, even at this early age. Practice-based strategies to reduce missed opportunities and prenatal WIC enrollment should be focused especially toward those at highest risk of underimmunization.

California↗

Estimation of diagnostic-test sensitivity and specificity through Bayesian modeling.

We review recent Bayesian approaches to estimation (based on cross-sectional sampling designs) of the sensitivity and specificity of one or more diagnostic tests. Our primary goal is to provide veterinary researchers with a concise presentation of the computational aspects involved in using the Bayesian framework for test evaluation. We consider estimation of diagnostic-test sensitivity and specificity in the following settings: (i) one test in one population, (ii) two conditionally independent tests in two or more populations, (iii) two correlated tests in two or more populations, and (iv) three tests in two or more populations, where two tests are correlated but jointly independent of the third test. For each scenario, we describe a Bayesian model that incorporates parameters of interest. The WinBUGS code used to fit each model, which is available at http://www.epi.ucdavis.edu/diagnos-tictests/, can be altered readily to conform to different data.

Animals↗

Body mass index in elementary school children, metropolitan area food prices and food outlet density.

OBJECTIVE: The aim of this study was to examine the association between food prices and food outlet density and changes in the body mass index (BMI) among elementary school children in the USA. METHODS: The Early Childhood Longitudinal Study followed a nationally representative sample of kindergarten children over 4 years. We merged individual-level data to (a) metropolitan data on food prices and (b) per capita number of restaurants, grocery stores and convenience stores in the child's home and school zip code. The dependent variables were BMI changes over 1 and 3 years. We analysed mean changes with least-squares regression, and median changes and 85th percentile changes with quantile regression. We controlled for baseline BMI, age, real family income and sociodemographic characteristics. RESULTS: Lower real prices for vegetables and fruits were found to predict a significantly lower gain in BMI between kindergarten and third grade; half of that effect was found between kindergarten and first grade. Lower meat prices had the opposite effect, although this effect was generally smaller in magnitude and was insignificant for BMI gain over 3 years. Differences across subgroups were not statistically significant due to smaller sample sizes in subgroup analyses, but the estimated effects were meaningfully larger for children in poverty, children already at risk for overweight or overweight in kindergarten, and Asian and Hispanic children. There were no significant effects for dairy or fast-food prices, nor for outlet density, once we had controlled for individual characteristics and random intercepts to adjust standard errors for the sampling design. DISCUSSION: The geographic variation in fruit and vegetable prices is large enough to explain a meaningful amount of the differential gain in BMI among elementary school children across metropolitan areas. However, as consumption information was not available, we cannot confirm that this is the actual pathway. We found no effects of food outlet density at the neighbourhood level, possibly because availability is not an issue in metropolitan areas.

Body Mass Index↗