A prolonged ED stay for older admitted patients is associated with an increased risk of an in-hospital AE. The longer hospital LOS associated with AEs further reduces the availability of acute care beds, thus exacerbating ED crowding.

Estrogen and its metabolites are believed to play important roles in breast cancer. The influence of genetic polymorphisms in the enzymes responsible for formation and disposition of estrogen on breast cancer risk may shed light on the importance of estrogen metabolites in this disease. However, for such studies to be valid, it is important to correctly identify the enzymes involved in estrogen bioactivation. Therefore, we assessed the human cytochrome P450 -dependent oxidation of estrone using substrate concentrations that more closely approximate the maximum expected concentrations in breast tissue. The in vitro metabolism of estrone by recombinant human cytochrome P450 enzymes and human liver microsomes was studied. The formation of estrone metabolites (2-hydroxyestrone, 4-hydroxyestrone, and 16A-hydroxyestrone) was monitored by high-performance liquid chromatography. 2-Hydroxyestrone formation was catalyzed predominantly by CYP1A2, CYP1A1, and CYP1B1 enzymes; 4-hydroxyestrone formation was catalyzed predominantly by CYP1B1, CYP1A2, and CYP1A1 enzymes; and 16A-hydroxyestrone formation was catalyzed predominantly by CYP2C19, CYP1A1, and CYP3A5. This study confirms the important role of members of the CYP1 family in the 2-hydroxylation and 4-hydroxylation of estrone, but the enzymes identified as responsible for the 16A-hydroxylation of estrone are different from those previously identified. The relative importance of these enzymes in vivo would depend on the specific tissue expression of the enzymes. These enzymes are all known to be genetically variant in the human population, and additional studies to assess the role CYP1A2, CYP2C19, and CYP3A5 in breast cancer risk are indicated. (Cancer Epidemiol Biomarkers Prev 2006;15(3):551 -8)

CAISP is a new agricultural injury surveillance program in Canada. Data from this system are actively used to inform prevention initiatives, and to indicate priorities for etiological and experimental research in the Canadian agricultural setting.

Ambient and non-ambient particles have different risk management approaches, composition, and likely toxicity. Therefore, a better understanding of their contribution to the indoor environment is important to manage the health risks associated with fine particles (FPs) effectively. As well, a better understanding of the factors Finf can help improve exposure assessment and contribute to reduced exposure misclassification in epidemiologic studies.

No abstract

The incidence of allergic alveolitis (AA) and of febrile reactions (FR) to inhaled mold dust in those who did not meet the criteria of AA was investigated in Swedish farmers, and the findings were related to farming methods and exposure type. A questionnaire was completed by 6,702 farmers. A stratified sample of 390 farmers underwent examination comprising spirometry, a skin-prick test, blood tests for precipitating antibodies and total IgE and an interview concerning symptoms, exposure and farming methods. The yearly incidence of AA was 2–3/10,000 farmers. The incidence of FR was 30–50 times higher (1/100 farmers) and the majority of these reactions was of a toxic rather than allergic type (organic dust toxic syndrome). Among farmers with recent FR or AA there was a higher frequency of positive precipitin reactions (p < 0.05). Exposures to moldy grain, straw, wood chips and hay were associated with both AA and FR. A major difference in exposure between 17 farmers with AA and 80 with FR was that AA appeared to require repeated exposure, while FR was associated with occasional heavy exposure to mold dust.

Canadians value ease of access to their health services. Although many studies have focused on accessibility to health services in Canada, few have examined rural-urban differences in this aspect, particularly from a national perspective. Yet disparities in access to health services exist between rural and urban populations, as do the challenges of delivering health care to more remote areas or to those with small populations. “Canada’s Rural Communities: Understanding Rural Health and Its Determinants” is a three-year research project co-funded by the Canadian Population Health Initiative (CPHI) of the Canadian Institute for Health Information (CIHI) and the Public Health Agency of Canada (PHAC). It involves investigators from the Public Health Agency of Canada, the Centre for Rural and Northern Health Research (CRaNHR) at Laurentian University, and other researchers. The first publication of the research project was How Healthy Are Rural Canadians? An Assessment of Their Health Status and Health Determinants;Footnote 1a1a this, the second publication, is a descriptive analysis of the utilization patterns of a broad range of health services by rural residents compared to their urban counterparts.

Residential wood combustion is an important source of ambient air pollution, accounting for over 25% of fine particulate matter (PM2.5) emissions in Canada. In addition to these ambient contributions, wood smoke pollutants can enter the indoor environment directly when loading or stoking stoves, resulting in a high potential for human exposure. A study of the effectiveness of air cleaners at reducing wood smoke-associated PM2.5 of indoor and outdoor origin was conducted in 31 homes during winter 2009-10. Day 1, the residents' wood burning appliance operated as usual with no air cleaner. Days 2 and 3, the wood burning appliance was not operational and the air cleaner was randomly chosen to operate in "filtration" or "placebo filtration" mode. When the air cleaner was operating, total indoor PM2.5 levels were significantly lower than on placebo filtration days (p = 0.0001) resulting in a median reduction of 52%. There was also a reduction in the median PM2.5 infiltration factor from 0.56 to 0.26 between these 2 days, suggesting the air cleaner was responsible for increased PM2.5 deposition on filtration days. Our findings suggest that the use of an air cleaner reduces exposure to indoor PM2.5 resulting from both indoor and ambient wood smoke sources.