Reproductive potential of stable flies (Diptera: Muscidae) fed cattle, chicken, or horse blood

Reproductive potential was assessed for stable fly cohorts fed cattle, chicken, or horse blood. Flies provided chicken blood oviposited 20% more eggs per day than did those fed cattle or horse blood. However, flies provided cattle or horse blood were fecund 50% longer. When both egg viability and number of eggs produced were considered, lifetime reproductive potential was almost twice as high for flies fed cattle or chicken blood than for flies fed horse blood. Maternal investment, which took egg production and volume into account, was higher in cohorts fed cattle blood (70 mm3) when compared with the other treatments (chicken = 54 mm3, horse = 55 mm3). This is the first report of stable flies producing viable eggs after feeding on bird blood. Results from this study in addition to field observations indicate that stable fly interactions with birds may be limited to relatively low risk scenarios.     

Response to infections in patients with asthma and atopic disease: An epiphenomenon or reflection of host susceptibility?

Associations between respiratory tract infections and asthma inception and exacerbations are well established. Infant respiratory syncytial virus and rhinovirus infections are known to be associated with an increased risk of asthma development, and among children with prevalent asthma, 85% of asthma exacerbations are associated with viral infections. However, the exact nature of this relationship remains unclear. Is the increase in severity of infections an epiphenomenon, meaning respiratory tract infections just appear to be more severe in patients with underlying respiratory disease, or instead a reflection of altered host susceptibility among persons with asthma and atopic disease? The main focus of this review is to summarize the available levels of evidence supporting or refuting the notion that patients with asthma or atopic disease have an altered susceptibility to selected pathogens, as well as discussing the biological mechanism or mechanisms that might explain such associations. Finally, we will outline areas in need of further research because understanding the relationships between infections and asthma has important implications for asthma prevention and treatment, including potential new pathways that might target the host immune response to select pathogens.     

Night work and breast cancer risk among Norwegian nurses: assessment by different exposure metrics

Associations between night work and breast cancer risk were investigated in a nested case-control study within a cohort of 49,402 Norwegian nurses. A total of 699 (74%) of the live cases diagnosed in 1990-2007 and 895 (65%) controls, cancer free at the time of sampling, were interviewed about work history and potential risk factors. The odds ratios for risk of breast cancer in relation to different exposure metrics were estimated by multivariate unconditional logistic regression models. No increase of risk was found after long duration of work by nurses working ≥3 night shifts per month. Small, nonsignificantly increased risks were observed for exposure to ≥30 years in hospitals or other institutions (odds ratio (OR) = 1.1), ≥12 years in schedules including night work (OR = 1.3), ≥1,007 night shifts during the lifetime (OR = 1.2), and lifetime average number of ≥4 night shifts per month (OR = 1.2). Nonsignificantly increased risks of breast cancer were observed in nurses who worked ≥5 years with ≥4 (OR = 1.4) and ≥5 (OR = 1.6) consecutive night shifts. Significantly increased risks were seen in nurses who worked ≥5 years with ≥6 consecutive night shifts (OR = 1.8, 95% confidence interval: 1.1, 2.8). The results suggest that risk may be related to number of consecutive night shifts.     

Levonorgestrel-releasing and copper intrauterine devices and the risk of breast cancer

Background

This study compares the risk of breast cancer for levonorgestrel-releasing intrauterine devices (LNG_IUD) versus copper IUDs (CU_IUD) in women younger than 50 years of age.

Study Design

Retrospective, population-based, case-control study using cancer registers in Finland and Germany, powered to exclude a 1.5-fold risk of breast cancer.

Results

Analysis of 5113 breast cancer cases diagnosed 2000–2007 and 20,452 controls — matched by year of birth and area of residence — yielded relative risk estimates approaching unity with 95% CI crossing 1.0 for all comparisons, including ever-use of LNG_IUD versus CU_IUD (adjusted OR, 0.99; 95% CI, 0.88–1.12) and current use at time of diagnosis (adjusted OR, 0.85; 95% CI, 0.52–1.39), as well as for sub-analyses by country, age, tumor characteristics and period, recency and duration of use prior to diagnosis.

Conclusion

This study does not indicate an increased risk of breast cancer for users of LNG_IUD. No indications for tumor promotion or tumor induction were found.     

Influence of income, income inequalities and social capital on the health of persons aged 65 and over in Spain in 2007

The aim of this study is to evaluate the influence of personal income [absolute income hypothesis (AIH)], income inequality and welfare [relative income hypothesis (RIH)], and social capital on the health of older people. Multi-level, cross-sectional logit models are calculated separately for women and men. The database employed was the Spanish Life Conditions Survey for 2007. The population consists of 6,259 persons aged over 65 years living in the 17 autonomous regions of Spain. The results confirm the AIH hypothesis: higher personal income is associated with better health. Education is also associated with better self-perceived health. The RIH hypothesis is partially confirmed due to the association between the Gini coefficient, regional per capita welfare and self-perceived health in older people, but only for women. Two different measures of social capital are used: the value of services of social capital and the percentage of people aged over 65 belonging to an association. Both factors are statistically associated with better self-perceived health in women. This study is the first to contrast the associations among income, income inequalities, social capital and the health of elders in Spain.     

Deletion of the A35 gene from Modified Vaccinia Virus Ankara increases immunogenicity and isotype switching

We show here that the immunogenicity of the Modified Vaccinia Ankara MVA vaccine strain can be improved by deletion of the A35 gene, without diminishing the ability of the virus to replicate. Deletion of the A35 gene resulted in increased virus-specific immunoglobulin production, class switching to IgG isotypes, and virus-specific IFNγ-secreting splenocytes. The MVA35 deletion virus provided excellent protective efficacy against virulent virus challenge. These results suggest that A35 deletion mutant strains will have superior vaccine performance for poxvirus vaccines as well as platform vaccines for other infectious diseases and cancer.