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ABSTRACTAccumulating evidence suggests that two chronic respiratory diseases, nontuberculous mycobacterium (NTM)-pulmonary disease (PD) and allergic asthma, are frequently present together and that they likely influence the disease development and progression of each other. However, their precise interactions regarding the pathogenesis of comorbid diseases versus that of individual diseases are not well understood. In this study, comorbid diseases (i.e., Mycobacteria avium (Mav) pulmonary infection (PI) (Mav-PI) and ovalbumin-induced allergic asthma) were established in mice in different orders and at different time periods. Individual disease-specific characteristics, including alterations in immune cell populations and antigen-specific immune responses, were analyzed and compared. To assess Mav-PI pathogenesis, lung inflammation and bacterial burden levels were also determined. Allergic asthma induction in the presence of Mav-PI markedly aggravated Mav-PI pathogenesis by increasing the bacterial burden and the severity of lung inflammation. Interestingly, the general outcome of allergic asthma with goblet cell hyperplasia was alleviated at a chronic stage in the comorbid mouse model. Overall, the increase in the number of Mav CFUs was inversely correlated with the Mav-specific Th17 response, as confirmed by comparing BALB/c and C57BL/6J mice. Overall, the pathogenesis of existing Mav-PI is more severely affected by allergen exposure than vice versa. This Mav-PI exacerbation is associated with disruption of Mav-specific Th17 responses. This study provides the first evidence that the Mav-specific Th17 response plays an important role in the control of Mav pathogenesis in the presence of allergic asthma, indicating that targeting the Th17 response has therapeutic potential for NTM-PD accompanied by allergic asthma.

Collagen is a skeleton of native extracellular matrix (ECM) that is known to provide mechanical and structural stability. In an attempt to develop a new connective cellular model with the surrounding ECM without further experimental complications, such as the reconstitution of ECM receptors, we designed the experiments and discovered that the fibrillogenesis of membrane-bound collagen is not spontaneous as it is in the form of free collagen in bulk solution. The confocal microscopic results suggest that cholesterol is a crucial component that facilitates the fibril formation on the membrane surface. In situX-ray and neutron reflectivity on Langmuir monolayer and solid-supported lipid bilayer models, respectively, reveal two features of cholesterol effects on the collagen fibril formation. Mainly, cholesterol increases the lateral lipid headgroup separation on the membrane surface, which promotes the association degree of collagen monomers. It also enhances the elastic modulus of the membrane to impede membrane filtration by the collagen assemblies.

AbstractThis study investigated contributions of pre-service teachers’ endogenous and exogenous instrumentalities, their intrinsic and extrinsic motivations, and their use of self-regulation strategies to explain the extent to which they used strategies to purposefully integrate their knowledge across courses (extensive knowledge integration). With a total of 254 pre-service teachers’ survey-responses, results of a hierarchical multiple regression analysis indicated that their endogenous instrumentality of their current coursework (i.e. seeing their course work as instrumentally connected to their future careers), their use of metacognitive strategies and their use of deeper cognitive learning strategies (e.g. elaboration and critical thinking) contributed to explaining their use of extensive knowledge integration strategies for completing coursework. Our results suggest that to develop pre-service teachers’ teaching expertise, they may need to (a) have a strong understanding that the current course content and their future goals are instrumentally linked, (b) be able to initiate planning and self-monitoring for learning and (c) use strategies for deep learning that integrates their knowledge across courses.

Polymerization of 1,2-bis(tricosa-10,12-dinoyl)-sn-glycero-3-phosphocholine, DC8.9PC, which is a photo-polymerizable lipid, has been systematically investigated in various biological membrane-mimicking models as hosting matrices, for example, small unilamellar vesicles, giant unilamellar vesicles and Langmuir monolayers. In liposome systems, it has been observed that the photo-crosslinking (PCL) reaction between DC8.9PCs occurred only in gel phases composed of saturated lipids. No reaction was observed when DC8.9PCs were mixed with unsaturated lipids that intrinsically form a liquid phase, even when a high concentration of DC8.9PC was added. To explain how the existence of the gel phase-matrix induces polymerization, a mixed Langmuir monolayer system between DC8.9PC and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), where the lipid phases can be controlled, has been used. We found that the PCL reaction only occurred at liquid-condensed (LC) phases, and the reaction rates were strongly dependent on the packing states of the monolayers. Therefore, DC8.9PCs were possibly distributed in the LC domains of DPPCs, which consequently made the cross-distance between DC8.9PCs sufficiently small for the PCL reaction to proceed.