Association of the TLR4 Asp299Gly polymorphism with lung function in relation to body mass index

<p>Abstract</p> <p>Background</p> <p>Previous studies have shown conflicting results for the association between TLR4 polymorphism (Asp299Gly) and lung function. We investigated the influence of TLR4 Asp299Gly, a polymorphism, on lung function in a community population.</p> <p>Methods</p> <p>In 2003, a cross-sectional survey was conducted to assess the respiratory health of residents living in and around the town of Humboldt, Saskatchewan, Canada. There were 2090 adults age 18-79 years who completed a questionnaire that included a medical and smoking history, as well as socio-economic and lifestyle variables. Genetic information and lung function test measurements were available on 1725 subjects (754 males and 971 females) of the 2090 respondents. These subjects were selected for further analysis to investigate the association between TLR4 Asp299Gly genotype and forced expiratory volume in the first second in liters (FEV₁), forced vital capacity in liters (FVC), FEV₁/FVC ratio, and forced expiratory flow rate in liters/second (FEF_25-75). Multivariable linear regression analysis was used to investigate associations.</p> <p>Results</p> <p><b>A</b>djusted mean values of FEV₁and FVC were significantly different between TLR4 wild type and TLR4 variant groups [Mean ± S.E.: (TLR4 wild type - FEV₁: 3.18 ± 0.02, FVC: 3.95 ± 0.03; TLR4 variant - FEV₁: 3.31 ± 0.06, FVC: 4.14 ± 0.07)]. Based on multivariable regression analysis, we observed that body mass index (BMI) was associated with decreased FEV₁/FVC ratio and FEF_25-75in TLR4 variant group but not in wild type group.</p> <p>Conclusion</p> <p>BMI may modify the associations of TLR4 Asp299Gly polymorphism with FEV₁/FVC ratio and FEF_25-75.</p

Composition of Human Skin Microbiota Affects Attractiveness to Malaria Mosquitoes

The African malaria mosquito Anopheles gambiae sensu stricto continues to play an important role in malaria transmission, which is aggravated by its high degree of anthropophily, making it among the foremost vectors of this disease. In the current study we set out to unravel the strong association between this mosquito species and human beings, as it is determined by odorant cues derived from the human skin. Microbial communities on the skin play key roles in the production of human body odour. We demonstrate that the composition of the skin microbiota affects the degree of attractiveness of human beings to this mosquito species. Bacterial plate counts and 16S rRNA sequencing revealed that individuals that are highly attractive to An. gambiae s.s. have a significantly higher abundance, but lower diversity of bacteria on their skin than individuals that are poorly attractive. Bacterial genera that are correlated with the relative degree of attractiveness to mosquitoes were identified. The discovery of the connection between skin microbial populations and attractiveness to mosquitoes may lead to the development of new mosquito attractants and personalized methods for protection against vectors of malaria and other infectious diseases

Respiratory Symptoms and Asthma in Two Farming Populations: A Comparison of Hutterite and Non-Hutterite Children

OBJECTIVE: To determine the prevalence of asthma and respiratory symptoms in a farming population of Hutterite and non-Hutterite children

Allergic rhinitis and genetic components: focus on Toll-like receptors (TLRs) gene polymorphism

Zhiwei Gao1, Donna C Rennie2, Ambikaipakan Senthilselvan11Department of Public Health Sciences, School of Public Health, University of Alberta, Edmonton, Alberta, Canada; 2College of Nursing and Canadian Centre for Health and Agricultural Safety, University of Saskatchewan, Saskatoon, Saskatchewan, CanadaAbstract: Allergic rhinitis represents a global health issue affecting 10% to 25% of the population worldwide. Over the years, studies have found that allergic diseases, including allergic rhinitis, are associated with immunological responses to antigens driven by a Th2-mediated immune response. Because Toll-like receptors (TLRs) are involved in both innate and adaptive immune responses to a broad variety of antigens, the association between polymorphisms of TLRs and allergic diseases has been the focus in many animal and human studies. Although the etiology of allergic rhinitis is still unknown, extensive research over the years has confirmed that the underlying causes of allergic diseases are due to many genetic and environmental factors, along with the interactions among them, which include gene&amp;ndash;environment, gene&amp;ndash;gene, and environment&amp;ndash;environment interactions. Currently, there is great inconsistency among studies mainly due to differences in genetic background and unique gene&amp;ndash;environment interactions. This paper reviews studies focusing on the association between TLR polymorphisms and allergic diseases, including allergic rhinitis, which would help researchers better understand the role of TLR polymorphisms in the development of allergic rhinitis, and ultimately lead to more efficient therapeutic interventions being developed.Keywords: allergic rhinitis, allergic diseases, Toll-like receptor

Predictors of respiratory symptoms in a rural Canadian population: A longitudinal study of respiratory health

BACKGROUND: Predictors of new and long-term respiratory symptoms for rural residents are not well defined

Obesity, Diet, and Activity in relation to Asthma and Wheeze among Rural Dwelling Children and Adolescents

Aims and Objectives. We investigated associations between weight status, activity level, and diet with asthma or wheeze as well as the interrelationship between these factors. Methods. We conducted a case-control study of 6-18-year olds from 2005 to 2007. Cases ( = 87) were subjects reporting episodes or breathing medication use along with doctor-diagnosed asthma or wheeze in the past 12 months. Controls were randomly selected ( = 208) and without asthma or wheeze. Data regarding health outcomes, diet, and activity were obtained from questionnaire. Objectively measured height and weight were collected. Results. In the adjusted analysis, there was a trend ( = 0.07) towards an increased risk of asthma or wheeze associated with high fast food and/or pop consumption. Among cases, a significantly lower proportion (66%) classified as overweight participated in hard exercise in ≥9 of the past 14 days compared to those who were not overweight (86%). This pattern was not seen among controls (76% participating in hard exercise versus 78%, resp.). However, based on perceived weight status by the parent, the patterns were similar regardless of case-control status. Conclusions. Overweight status may negatively impact activity level among those with asthma or wheeze. Efforts should be made to encourage healthy food choices, and activity programming must consider the needs of overweight children with asthma