Assessment of the Toll-like receptor 3 pathway in endosomal signaling.

The innate immune system plays key roles in antimicrobial responses by developing the pattern-recognition receptors that recognize microbial components. The endosomal Toll-like receptors (TLRs) and cytosolic RIG-I-like receptors (RLRs) both recognize viral nucleic acids and are essential for antiviral immunity. Recent evidence suggests that compartmentalization of the receptors, and also their adaptor molecule, is important for discrimination between self and nonself and for distinct innate immune signals. TLR3 is a type I transmembrane protein that localizes in the endosomal membrane in myeloid dendritic cells (DCs) and fibroblasts/epithelial cells. TLR3 recognizes extracellular viral double-stranded RNA (dsRNA) and the synthetic dsRNA, poly(I:C). On recognition of dsRNA in the endosomes, TLR3 oligomerizes and induces type I interferon and proinflammatory cytokine production via an adaptor molecule, TICAM-1 (also known as TRIF). Additionally, the TLR3 signal in DCs triggers gene transcription required for DC maturation and the activation of natural killer cells and cytotoxic T lymphocytes. Remarkably, it has been reported that extracellular dsRNA is also recognized by cytosolic RLR. Making a distinction between TLR3-mediated endosomal signaling and RLR-mediated signaling is key to understanding the role of these receptors in innate immunity.

Factors associated with health service utilization in Ulaanbaatar, Mongolia: a population-based survey.

BACKGROUND: Understanding patterns of health service utilization can improve health care and increase use of health services. We examined patterns of health service utilization among residents of Ulaanbaatar, Mongolia. METHODS: A total of 500 adults were surveyed using paper-based questionnaires. The χ(2) test and multiple logistic regression were used to identify associations between factors. RESULTS: 44.1% of respondents had visited a physician during the previous 12 months. After controlling for determinants, the significant predictors of utilization of health service were attention to health examinations (OR = 3.6, CI: 1.93-6.76), being married (OR = 2.7, CI: 1.50-4.72), being satisfied with the overall cleanliness of the hospital (OR = 2.4, CI: 1.12-5.19), being a nonsmoker (OR = 2.2, CI: 1.21-3.98), having periodic physical examinations (OR = 2.2, CI: 1.25-3.71), not being a hospital patient during the previous 3 years (OR = 2.1, CI: 1.22-3.73), having proper documentation (OR = 1.9, CI: 1.10-3.43), having medical insurance (OR = 1.9, CI: 1.96-3.28), not wanting to receive information on food and nutrition (OR = 0.6, CI: 0.36-0.96), having more than 5 household members (OR = 0.5, CI: 0.50-0.85), low income (OR = 0.5, CI: 0.30-0.85), lack of concern for food and nutrition (OR = 0.5, CI: 0.28-0.84), self-medication during the past 12 months (OR = 0.4, CI: 0.24-0.69), and desire for treatment abroad (OR = 0.4, CI: 0.20-0.60). CONCLUSIONS: A number of health-related behaviors and sociodemographic factors were important predictors of health service utilization.