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Concept and knowledge maps have been shown to improve students’ learning by emphasising meaningful relationships between phenomena. A user-friendly online tool that enables assessment of students’ maps with automated feedback might therefore have significant benefits for learning. For that purpose, we developed an online software platform known as Knowledge Maps. Two pilot studies were performed to evaluate the usability and efficacy of Knowledge Maps. Study A demonstrated significantly improved perceptions of learning after using Knowledge Maps to learn pathology. Study B showed significant improvement between pre-test and post-test scores in an anatomy course. These preliminary studies indicate that this software is readily accepted and may have potential benefits for learning.

The driving pattern of three-wheeled auto-rickshaws is governed by commuter's demands on certain fixed roads that offer flexible mobility solutions in a mid-size city. This flexibility creates unique driving patterns, frequent stop-and-go conditions, frequent acceleration, braking, and excessive idling, which affect emission rates. Existing emission testing regulation based on the driving cycle does not represent real-world conditions. In this paper, the real-world driving cycle of three-wheeled auto-rickshaw has been developed to provide realistic CO, HC, and NOX pollutants and see the effect of introducing modal shift of electric auto-rickshaw to reduce emission for India. Two policy scenarios were evaluated (1) with a 5% modal shift to electric auto-rickshaw, and (2) without modal shift. The results indicate that with a 5% shift to electric auto-rickshaw, by 2030, emissions will decrease by 6.30% compared to the baseline scenario. Further, by 2030, the projected CO emission would be 1,696,670 ton/year, and HC and NOX emissions would be 2,067,371 ton/year. Results can be useful for policy interventions towards cleaner fuel and the aggressive adoption for reducing pollution from auto-rickshaw.

Chronic obstructive pulmonary disease (COPD), one of the leading causes of death in the world, is a chronic inflammatory disease of the airways usually caused by long-term exposure to inhaled irritants. Airway epithelial cells (AECs) play a key role in initializing COPD and driving the exacerbation of this disease through the release of various cytokines. This AEC-derived cytokine response is tightly regulated possibly through the regulatory effects of noncoding RNAs (ncRNAs). Although the importance of ncRNAs in pulmonary diseases has been increasingly realized, little is known about the role of ncRNA in the regulation of inflammatory responses in COPD. This review outlines the features of AEC-derived cytokine responses in COPD and how ncRNAs regulate these inflammatory responses.

A method for constructively using non-line-of-sight GNSS signals from a snapshot of signal samples for positioning of users in urban areas is presented here. Using a 3D building model and a ray-tracing algorithm, the number of reception paths and the corresponding path delays of reflected signals are predicted, across a rid of candidate positions. These predictions are then used to compute a least squares fit to the GNSS receiver’s correlator outputs, and the position with smallest residuals is selected as the position estimate. Using data collected along 3.5 km of road in downtown Calgary, Canada, where buildings reach heights of over 200 m, the root-mean-square position error is below 10 m in the along-track and across-track directions. Compared to two pseudorange-based receivers, the proposed method yields RMS error improvements of at least 31% in the along-track direction, 63% in the across-track direction, and 53% in the horizontal plane.

Summary In this review, we highlight experiments conducted in our laboratories that have elucidated functional roles for CD4+ T-helper type-2 lymphocytes (TH2 cells), their associated cytokines, and eosinophils in the regulation of hallmark features of allergic asthma. Notably, we consider the complexity of type-2 responses and studies that have explored integrated signaling among classical TH2 cytokines (IL-4, IL-5, and IL-13), which together with CCL11 (eotaxin-1) regulate critical aspects of eosinophil recruitment, allergic inflammation, and airway hyper-responsiveness (AHR). Among our most important findings, we have provided evidence that the initiation of TH2 responses is regulated by airway epithelial cell-derived factors, including TRAIL and MID1, which promote TH2 cell development via STAT6-dependent pathways. Further, we highlight studies demonstrating that microRNAs are key regulators of allergic inflammation and potential targets for anti-inflammatory therapy. On the background of TH2 inflammation, we have demonstrated that innate immune cells (notably, airway macrophages) play essential roles in the generation of steroid-resistant inflammation and AHR secondary to allergen- and pathogen-induced exacerbations. Our work clearly indicates that understanding the diversity and spatiotemporal role of the inflammatory response and its interactions with resident airway cells is critical to advancing knowledge on asthma pathogenesis and the development of new therapeutic approaches.

Airway epithelial cells (AEC) exhibit a pro-inflammatory phenotype in patients with allergic asthma. We examined the effect of an allergic cytokine environment on the response of AEC to rhinovirus (RV), the most common trigger of acute exacerbations of asthma. Calu-3 cells, a well-differentiated human AEC line, were cultured with or without the T-helper type 2 cytokines interleukin (IL)-4 and IL-13, then stimulated with a toll-like receptor (TLR) 3 agonist (poly I:C, dsRNA) or a TLR7 agonist (imiquimod), or infected with RV 16. Expression of pro-inflammatory and antiviral mediators, and of viral pattern-recognition molecules, was assessed using nCounter assays, quantitative real-time PCR (qRT-PCR) and protein immunoassays. Both dsRNA and imiquimod stimulated expression of mRNA for IL6 and IL8 whereas expression of several chemokines and antiviral response genes was induced only by dsRNA. Conversely, expression of other cytokines and growth factors was induced only by imiquimod. RV infection not only stimulated expression of the inflammation-related genes induced by dsRNA, but also of complement factor B and the novel pro-inflammatory cytokine IL-32. In the T helper type 2 (Th2) cytokine environment, several mediators exhibited significantly enhanced expression, whereas expression of interferons was either unchanged or enhanced. The allergic environment also increased expression of pattern-recognition receptors and of intercellular adhesion molecule 1, the cell surface receptor for RV. We conclude that Th2 cytokines promote increased production of pro-inflammatory mediators by AEC following infection with RV. Increased viral entry or enhanced signalling via pattern-recognition receptors could also contribute to the exaggerated inflammatory response to RV observed in allergic asthmatics.

The resurgence of mycobacterial infections and the emergence of drug-resistant strains urgently require a new class of agents that are distinct than current therapies. A group of 5-ethynyl ( 6 – 10 ), 5-(2-propynyloxy) ( 16 , 18 , 20 , 22 , 24 ), 5-(2-propynyloxy)-3- N -(2-propynyl) ( 17 , 19 , 21 , 23 , 25 ) and 5-hydroxymethyl-3- N -(2-propynyl) ( 30 – 33 ) derivatives of pyrimidine nucleosides were synthesized and evaluated against mycobacteria [ Mycobacterium tuberculosis ( Mtb ), Mycobacterium bovis ( BCG ) and Mycobacterium avium ], gram-positive bacteria ( Staphylococcus aureus and Enterococcus faecalis ) and gram-negative bacteria ( Escherichia coli , Salmonella typhimurium and Pseudomonas aeruginosa ) alone and in combination with existing drugs in in vitro assays. Although several compounds exhibited marked inhibitory activity at a higher concentration against Mtb , M. bovis , S. aureus and E. faecalis , they displayed unexpected synergistic and additive interactions at their lower concentrations with antitubercular drugs isoniazid and rifampicin, and antibacterial drug gentamicin. The active analogues were also found to inhibit intracellular Mtb in a human monocytic cell line infected with H37Ra. Oral administration of 5-hydroxymethyl-3- N -(2-propynyl)-3′-azido-2′,3′-dideoxyuridine ( 32 ) and 5-hydroxymethyl-3- N -(2-propynyl)-2′,3′-dideoxyuridine ( 33 ) at a dose of 100 mg/kg for two weeks showed promising in vivo effects in mice infected with Mtb (H37Ra). No in vitro cytotoxicity of the test compounds was observed up to the highest concentration tested (CC50 > 300 μg/mL).

Host immune responses play an important role in the outcome of infection with hepatitis C virus (HCV). They can lead to viral clearance and a positive outcome, or progression and severity of chronic disease. Extensive research in the past &gt, 25 years into understanding the immune responses against HCV have still resulted in many unanswered questions implicating a role for unknown factors and events. In our earlier studies, we made a surprising discovery that peptides derived from structural and non-structural proteins of HCV have substantial amino acid sequence homologies with various proteins of adenoviruses and that immunizing mice with a non-replicating, non-recombinant adenovirus vector leads to induction of a robust cross-reactive cellular and humoral response against various HCV antigens. In this work, we further demonstrate antibody cross-reactivity between Ad and HCV in vivo. We also extend this observation to show that recombinant adenoviruses containing antigens from unrelated pathogens also possess the ability to induce cross-reactive immune responses against HCV antigens along with the induction of transgene antigen-specific immunity. This cross-reactive immunity can (a) accommodate the making of dual-pathogen vaccines, (b) play an important role in the natural course of HCV infection and (c) provide a plausible answer to many unexplained questions regarding immunity to HCV.

Chronic obstructive pulmonary disease (COPD) is characterized by airway inflammation associated with a Th1/17-biased cytokine environment. Acute exacerbations of COPD (AECOPD) are most often triggered by respiratory infections, which elicit an exaggerated inflammatory response in these patients, via poorly defined mechanisms. We investigated the responses of airway epithelial cells (AECs) to infective stimuli in COPD and the effects of the Th1/17-biased environment on these responses. Cytokine expression was assessed following exposure to virus-like stimuli (poly I:C or imiquimod) or bacterial LPS. The effects of pretreatment with Th1/17 cytokines were evaluated in both primary AECs and the Calu-3 AEC cell line. We found that poly I:C induced increased expression of the proinflammatory cytokines IL1β, IL6, CXCL8, and TNF and IFN-β1 in AECs from both control subjects and COPD patients. Expression of IL1β in response to all 3 stimuli was significantly enhanced in COPD AECs. Primary AECs pretreated with Th1/17 cytokines exhibited enhanced expression of mRNA for proinflammatory cytokines in response to poly I:C. Similarly, Calu-3 cells responded to virus-like/bacterial stimuli with increased expression of proinflammatory cytokines, and a Th1/17 environment significantly enhanced their expression. Furthermore, increased expression of pattern recognition receptors for viruses (TLR3, TLR7, IFIH1, and DDX58) was induced by Th1/17 cytokines, in both primary AECs and Calu-3 cells. These findings suggest that the Th1/17-biased environment associated with COPD may enhance the proinflammatory cytokine response of AECs to viral and bacterial infections and that increased signaling via upregulated receptors may contribute to exaggerated inflammation in virus-induced AECOPD.

In vitro anti-mycobacterial activities of novel 4-amino-5-alkynylpyrimidine-2(1H)-ones were investigated. 4-Amino-5-heptynylpyrimidine-2(1H)-one (3) and 4-amino-5-(2-phenylethynyl)pyrimidine-2(1H)-one (7) displayed potent in vitro activity against Mycobacterium bovis and Mycobacterium tuberculosis. Compounds 3 and 7 were also assessed for their in vivo activity in BALB/c mice infected with M. tuberculosis (H37Ra). Both compounds showed promising in vivo efficacy at a dose of 25 mg/kg for 2 weeks. Importantly, compounds 3 and 7 interacted synergistically with the front-line anti-tuberculosis drug isoniazid in vitro and in vivo. These results suggest that this class of compounds has strong anti-mycobacterial potential.

Most of the healthcare costs associated with asthma relate to emergency department visits and hospitalizations because of acute exacerbations of underlying chronic disease. Development of appropriate animal models of acute exacerbations of asthma is a necessary prerequisite for understanding pathophysiological mechanisms and assessing potential novel therapeutic approaches. Most such models have been developed using mice. Relatively few mouse models attempt to simulate the acute-on-chronic disease that characterizes human asthma exacerbations. Instead, many reported models involve relatively short-term challenge with an antigen to which animals are sensitized, followed closely by an unrelated triggering agent, so are better described as models of potentiation of acute allergic inflammation. Triggers for experimental models of asthma exacerbations include (i) challenge with high levels of the sensitizing allergen (ii) infection by viruses or fungi, or challenge with components of these microorganisms (iii) exposure to environmental pollutants. In this review, we examine the strengths and weaknesses of published mouse models, their application for investigation of novel treatments and potential future developments.

Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis (Mtb), kills 5,000 people per day globally. Rapid development and spread of various multi drug-resistant strains of Mtb emphasize that an effective vaccine is still the most cost-effectives and efficient way of controlling and eradicating TB. Bacillus Calmette-Guerin (BCG), the only licensed TB vaccine, still remains the most widely administered human vaccine, but is inefficient in protecting from pulmonary TB in adults. The protective immunity afforded by BCG is thought to wane with time and considered to last only through adolescent years. Heterologous boosting of BCG-primed immune responses using a subunit vaccine represents a promising vaccination approach to promote strong cellular responses against Mtb. In our earlier studies, we discovered lipopeptides of ESAT-6 antigen with strong potential as a subunit vaccine candidate. Here, we have investigated that potential as a booster to BCG vaccine in both a pre-exposure preventive vaccine and a post-exposure therapeutic vaccine setting. Surprisingly, our results demonstrated that boosting BCG with subunit vaccine shortly before Mtb challenge did not improve the BCG-primed immunity, whereas the subunit vaccine boost after Mtb challenge markedly improved the quantity and quality of effector T cell responses and significantly reduced Mtb load in lungs, liver and spleen in mice. These studies suggest that ESAT-6 lipopeptide-based subunit vaccine was ineffective in overcoming the apparent immunomodulation induced by BCG vaccine in Mtb uninfected mice, but upon infection, the subunit vaccine is effective in re-educating the protective immunity against Mtb infection. These important results have significant implications in the design and investigation of effective vaccine strategies and immunotherapeutic approaches for individuals who have been pre-immunized with BCG vaccine but still get infected with Mtb.

Tuberculosis (TB) is a highly contagious infection and devastating chronic disease, causing 10.4 million new infections and 1.8 million deaths every year globally. Efforts to control and eradicate TB are hampered by the rapid emergence of drug resistance and limited efficacy of the only available vaccine, BCG. Immunological events in the airways and lungs are of major importance in determining whether exposure to Mycobacterium tuberculosis (Mtb) results in successful infection or protective immunity. Several studies have demonstrated that the host microbiota is in constant contact with the immune system, and thus continually directs the nature of immune responses occurring during new infections. However, little is known about its role in the eventual outcome of the mycobacterial infection. In this review, we highlight the changes in microbial composition in the respiratory tract and gut that have been linked to the alteration of immune responses, and to the risk, prevention, and treatment of TB. In addition, we summarize our current understanding of alveolar epithelial cells and the innate immune system, and their interaction with Mtb during early infection. Extensive studies are warranted to fully understand the all-inclusive role of the lung microbiota, its interaction with epithelium and innate immune responses and resulting adaptive immune responses, and in the pathogenesis and/or protection from Mtb infection. Novel interventions aimed at influencing the microbiota, the alveolar immune system and innate immunity will shape future strategies of prevention and treatment for TB.

Background: Allergic asthma is common in childhood and is associated with a T-helper type 2 (Th2)-biased immunological response. Exacerbations of asthma are characterised by increased inflammation of the airways, which appears to be driven by interleukin (IL)-33 that can activate pulmonary macrophages. The Th2 cytokine environment of allergic asthma may contribute to exaggerated airway inflammation. Objectives: To test this, we assessed whether production of pro-inflammatory cytokines by IL-33-stimulated macrophages was enhanced in cells pre-treated with the key Th2 cytokines IL-4 and IL-13. We also investigated whether this was associated with altered expression of regulatory microRNAs (miRNAs). Methods: RAW264.7 cells cultured with IL-4 and IL-13 for 48 h were stimulated with IL-33 for 4 h. Pro-inflammatory mediators were assessed using quantitative real-time PCR (RT-PCR). Expression of miRNAs was assessed using microarrays and RT-PCR. In further experiments, we examined whether resolvin E1 (RvE1), which promotes the resolution of experimental asthmatic inflammation in vivo, could suppress the enhanced response by treating cells with RvE1 concurrently with IL-33 stimulation. Results: In cells pre-treated with IL-4 and IL-13, expression of mRNA for Ccl3, Ccl5, Ccl17, Ccl24, and Il1b in response to IL-33 stimulation was significantly increased. This was paralleled by up-regulated expression of miR-155-5p, a miRNA that is predicted to regulate several aspects of allergic inflammation. RvE1 suppressed the enhanced production of Ccl3, Ccl5, Ccl24, and Il1b. Conclusions: We conclude that IL-33-activated macrophages may contribute to the exaggerated airway inflammation in exacerbations of allergic asthma, and that RvE1 has potential as a therapeutic agent that targets macrophages.

Background Although blended learning has the potential to enhance the student experience, both in terms of engagement and flexibility, it can be difficult to effectively restructure existing courses. To achieve these goals for an introductory Pathology course, offered to more than 250 undergraduate students at UNSW Sydney, we devised a novel approach. Methods For each topic presented over 2–3 weeks, a single face-to-face overview lecture was retained. The remaining content that had previously been delivered as conventional lectures was converted into short (12–18 min) online modules. These were based on lecture slides with added animations/highlights, plus narration using edited excerpts of previous lecture recordings. The modules also incorporated interactive questions and review quizzes with feedback which used various question types. Modules were developed in PowerPoint and iSpring and uploaded to Moodle as SCORM packages. Each topic concluded with an interactive large-group session focussing on integration of the content, with in-class questions to which students could respond via the Echo360 Active Learning Platform (ALP). Overall, more than 50% of face-to-face lecture time was replaced by online modules and interactive large-group sessions. Quantitative evaluation data included usage statistics from 264 students and feedback via online survey responses from 41 students. Qualitative evaluation data consisted of reflective commentaries from 160 student ePortfolios, which were analysed to identify factors affecting learning benefits and user acceptability. Results All of the modules were completed by 74% of students and on average, 83.1% of students eventually passed the optional review quizzes. Notably, 88.4% of students responded to in-class questions during the integration and feedback sessions via the ALP. Student reflections emphasised that the modules promoted understanding, which was reinforced through active learning. The modules were described as enjoyable, motivating and were appreciated for their flexibility, which enabled students to work at their own pace. Conclusions In transforming this introductory Pathology course, we have demonstrated a model for the use of blended learning in large group teaching sessions, which achieved high levels of completion, satisfaction and value for learning. Electronic supplementary material The online version of this article (10.1186/s12909-017-1057-2) contains supplementary material, which is available to authorized users.

To determine whether cytopathology whole slide images and virtual microscopy adaptive tutorials aid learning by postgraduate trainees, we designed a randomized crossover trial to evaluate the quantitative and qualitative impact of whole slide images and virtual microscopy adaptive tutorials compared with traditional glass slide and textbook methods of learning cytopathology. Forty-three anatomical pathology registrars were recruited from Australia, New Zealand, and Malaysia. Online assessments were used to determine efficacy, whereas user experience and perceptions of efficiency were evaluated using online Likert scales and open-ended questions. Outcomes of online assessments indicated that, with respect to performance, learning with whole slide images and virtual microscopy adaptive tutorials was equivalent to using traditional methods. High-impact learning, efficiency, and equity of learning from virtual microscopy adaptive tutorials were strong themes identified in open-ended responses. Participants raised concern about the lack of z-axis capability in the cytopathology whole slide images, suggesting that delivery of z-stacked whole slide images online may be important for future educational development. In this trial, learning cytopathology with whole slide images and virtual microscopy adaptive tutorials was found to be as effective as and perceived as more efficient than learning from glass slides and textbooks. The use of whole slide images and virtual microscopy adaptive tutorials has the potential to provide equitable access to effective learning from teaching material of consistently high quality. It also has broader implications for continuing professional development and maintenance of competence and quality assurance in specialist practice.

Background and objective Exacerbations of allergic asthma are often triggered by respiratory viral infections. We have previously shown that in a T-helper type 2 (Th2)-biased cytokine environment, mouse and human airway epithelial cells (AEC) exhibit increased expression of pro-inflammatory and anti-viral genes in response to synthetic double-stranded ribonucleic acid (dsRNA), a virus-like stimulus. This implies coordinated regulation of gene expression, suggesting possible involvement of microRNA. To investigate this, we developed a novel approach to identifying candidate microRNA using online databases, then confirmed their expression by quantitative real-time polymerase chain reaction (qRT-PCR). Methods Using a list of genes of interest, defined on the basis of the previous study as being up-regulated in a Th2 environment, we searched mouse and human microRNA databases for possible regulatory microRNA, and selected 10 candidates that were conserved across species or predicted by more than one human database. Expression of these microRNA was tested by qRT-PCR, in primary human AEC pre-treated with Th2 cytokines and exposed to dsRNA. Results Expression of hsa-miR-139-5p, miR-423-5p and miR-542-3p was significantly decreased in Th2 pre-treated AEC, and miR-135a-5p exhibited a trend towards decreased expression. Further database searches confirmed that these microRNA regulated additional pro-inflammatory and anti-viral response genes for which expression had previously been shown to be up-regulated, confirming the validity of this approach. Conclusions Our study demonstrates the value of using multiple online databases to identify candidate regulatory microRNA and provides the first evidence that in an allergic environment, microRNA may be important in altering the pro-inflammatory and anti-viral responses of human AEC during exacerbations of asthma.

Chronic infection with hepatitis C virus (HCV) afflicts 3% of the world’s population and can lead to serious and late-stage liver diseases. Developing a vaccine for HCV is challenging because the correlates of protection are uncertain and traditional vaccine approaches do not work. Studies of natural immunity to HCV in humans have resulted in many enigmas. Human beings are not immunologically naïve because they are continually exposed to various environmental microbes and antigens, creating large populations of memory T cells. Heterologous immunity occurs when this pool of memory T cells cross-react against a new pathogen in an individual. Such heterologous immunity could influence the outcome when an individual is infected by a pathogen. We have recently made an unexpected finding that adenoviruses, a common environmental pathogen and an experimental vaccine vector, can induce robust cross-reactive immune responses against multiple antigens of HCV. Our unique finding of previously uncharacterized heterologous immunity against HCV opens new avenues to understand HCV pathogenesis and develop effective vaccines.

In this review, we highlight experiments conducted in our laboratories that have elucidated functional roles for CD4+ T-helper type-2 lymphocytes (TH2 cells), their associated cytokines and eosinophils in the regulation of hallmark features of allergic asthma. Notably, we consider the complexity of Type-2 responses and studies that have explored integrated signaling among classical TH2 cytokines (IL-4, IL-5 and IL-13), which together with CCL11 (eotaxin-1) regulate critical aspects of eosinophil recruitment, allergic inflammation and airways hyperresponsiveness (AHR). Among our most important findings, we have provided evidence that the initiation of TH2 responses is regulated by airway epithelial cell-derived factors, including TRAIL and MID1, which promote TH2 cell development via STAT6-dependent pathways. Further, we highlight studies demonstrating that microRNA are key regulators of allergic inflammation and potential targets for anti-inflammatory therapy. On the background of TH2 inflammation, we have demonstrated that innate immune cells (notably, airway macrophages) play essential roles in the generation of steroid-resistant inflammation and AHR secondary to allergen and pathogen-induced exacerbations. Our work clearly indicates that understanding the diversity and spatiotemporal role of the inflammatory response and its interactions with resident airway cells is critical to advancing knowledge on asthma pathogenesis and the development of new therapeutic approaches.

Epithelial cells of the conducting airways are continuously exposed to infectious agents, allergens, and airborne irritants. These airway epithelial cells (AEC) contribute to both the innate and adaptive immunological response of the host, primarily via production of cytokines. AEC are a significant source of proinflammatory cytokines, chemokines, interferons, and other immune response-modulating cytokines. Several of these appear to play key roles in the induction of asthma and chronic obstructive pulmonary disease (COPD) as well as in acute exacerbations of these conditions. Production of cytokines by AEC appears to be upregulated in the setting of underlying chronic inflammation in both asthma and COPD. Epigenetic mechanisms involved in regulating cytokine expression by AEC are a current focus of research, although much remains to be learned.

Background and objective Exposure to airborne particulate matter (PM) may promote development of childhood asthma and trigger acute exacerbations of existing asthma via injury to airway epithelial cells (AEC). Methods We compared the response of AEC to ambient particulates with median aerodynamic diameters of

Exacerbations of asthma are most commonly triggered by viral infections, which amplify allergic inflammation. Cytokines released by virus-infected AECs may be important in driving this response. This review focuses on accumulating evidence in support of a role for epithelial cytokines, including IL-33, IL-25, and TSLP, as well as their targets, type 2 innate lymphoid cells (ILC2s), in the pathogenesis of virus-induced asthma exacerbations. Production and release of these cytokines lead to recruitment and activation of ILC2s, which secrete mediators, including IL-5 and IL-13, which augment allergic inflammation. However, little information is currently available about the induction of these responses by the respiratory viruses that are strongly associated with exacerbations of asthma, such as rhinoviruses. Further human studies, as well as improved animal experimental models, are needed to investigate appropriately the pathogenetic mechanisms in virus-induced exacerbations of asthma, including the role of ILCs.

Background and Aim Chronic hepatitis C virus infection is characterized by infiltration of a mixed population of leukocytes into portal tracts and infiltration almost exclusively by CD8+ T cells into lobules of the liver. This pattern of leukocyte recruitment is likely to be orchestrated in a cell-specific fashion by local chemokine expression. Methods Portal or lobular tissues were isolated by laser capture microdissection from 17 liver biopsy specimens to examine regional gene expression of a panel of chemokine ligands and receptors. The biopsies were also stained immunohistochemically to enumerate regional cell numbers. Results Expression of multiple chemokine ligands and receptors was evident, although few correlated with leukocyte numbers. In the lobule, expression of CXCL10 correlated with T-cell subsets (CD3+, P = 0.0002; CD4+, P = 0.0053; and CD8+, P = 0.0061), as did CCL5 (CD3+, P = 0.0005; CD8+, P = 0.0199) and CCL3 (CD3+, P = 0.0016; CD8+, P = 0.008). In the portal tracts, expression of CXCL10 and CCL5 was correlated with CD8+ T-cell numbers (P = 0.0040 and P = 0.0114, respectively), whereas CXCL13 was strongly correlated with CD20+ B-cell numbers (P

Global Navigation Satellite Systems (GNSS) has proven to be a viable and reliable solution in interference-free environment. However, in urban canyons reliable positioning is difficult to achieve in a cost-effective manner using standalone GNSS, due to multipath problems and Non-Line-of-Sight (NLOS) signals. In this regard, the authors previously proposed a method whereby NLOS signals were used constructively by incorporating the information related to nearby reflectors with the help of a 3D building model (3DBM). Since the proposed 3DBM-assisted algorithm incorporates assistance data with the help of a 3DBM, the accuracy of the final estimated position will also depend on the accuracy of the assistance data and processing parameters. This research investigates the sensitivity of the 3DBMassisted positioning algorithm to various algorithm parameters and is tested using data collected in downtown Calgary, Canada. Results confirm that errors in the 3DBM increase the error of the final position estimate. For given grid resolution, the size of the position grid does not affect the final solution. Increasing the grid resolution yields slightly better position estimates at the cost of much higher processing load. The algorithm is shown to be weakly sensitive to the accuracy of receiver’s time estimate; even with a timing error of 10 s, the final estimated position was unchanged. Finally, the coherent integration time (10 ms vs 100 ms) was shown to have very little impact on position accuracy and demonstrates the capability of the algorithm to provide good positioning accuracy without external data bit aiding even in dense urban environments.

Student interest in botany and enrolment in plant sciences courses tends to be low compared to that in other biological disciplines. One potential way of increasing student interest in botany is to focus on course material designed to raise student enthusiasm and satisfaction. Here, we introduce and evaluate virtual microscopy in botany teaching. Virtual microscopy uses high-resolution digital ‘virtual slides’ that allow students to explore microscope sections without the advanced skills required to prepare glass slides. Questionnaire feedback from students indicated that students found the virtual slides an effective learning tool. Further, we found that student performance in assessments was significantly higher when using virtual slides than when using traditional glass slides. We suggest that virtual slides are an effective tool for increasing student satisfaction in introductory botany courses, and have the potential for increasing student enrolment in higher-level courses (honours) and research degrees.

Summary Childhood exposure to environmental particulates increases the risk of development of asthma. The underlying mechanisms might include oxidant injury to airway epithelial cells (AEC). We investigated the ability of ambient environmental particulates to contribute to sensitization via the airways, and thus to the pathogenesis of childhood asthma. To do so, we devised a novel model in which weanling BALB/c mice were exposed to both ambient particulate pollutants and ovalbumin for sensitization via the respiratory tract, followed by chronic inhalational challenge with a low mass concentration of the antigen. We also examined whether these particulates caused oxidant injury and activation of AEC in vitro. Furthermore, we assessed the potential benefit of minimizing oxidative stress to AEC through the period of sensitization and challenge by dietary intervention. We found that characteristic features of asthmatic inflammation developed only in animals that received particulates at the same time as respiratory sensitization, and were then chronically challenged with allergen. However, these animals did not develop airway hyper-responsiveness. Ambient particulates induced epithelial injury in vitro, with evidence of oxidative stress, and production of both pro-inflammatory cytokines and Th2-promoting cytokines such as IL-33. Treatment of AEC with an antioxidant in vitro inhibited the pro-inflammatory cytokine response to these particulates. Ambient particulates also induced pro-inflammatory cytokine expression following administration to weanling mice. However, early-life dietary supplementation with antioxidants did not prevent the development of an asthmatic inflammatory response in animals that were exposed to particulates, sensitized and challenged. We conclude that injury to airway epithelium by ambient environmental particulates in early life is capable of promoting the development of an asthmatic inflammatory response in sensitized and antigen-challenged mice. These findings are likely to be relevant to the induction of childhood asthma.

Adenoviruses (Ad) are commonly used as vectors for gene therapy and/or vaccine delivery. Recombinant Ad vectors are being tested as vaccines for many pathogens. We have made a surprising observation that peptides derived from various hepatitis C virus (HCV) antigens contain extensive regions of homology with multiple adenovirus proteins, and conclusively demonstrate that adenovirus vector can induce robust, heterologous cellular and humoral immune responses against multiple HCV antigens. Intriguingly, the induction of this cross-reactive immunity leads to significant reduction of viral loads in a recombinant vaccinia-HCV virus infected mouse model, supporting their role in antiviral immunity against HCV. Healthy human subjects with Ad-specific pre-existing immunity demonstrated cross-reactive cellular and humoral immune responses against multiple HCV antigens. These findings reveal the potential of a previously uncharacterized property of natural human adenovirus infection to dictate, modulate and/or alter the course of HCV infection upon exposure. This intrinsic property of adenovirus vectors to cross-prime HCV immunity can also be exploited to develop a prophylactic and/or therapeutic vaccine against HCV.

Asthma is increasingly being recognised as involving not only allergic inflammatory mechanisms but also a variety of other cell types and cytokines. While the role of interferon-γ(IFN-γ) in asthma remains controversial, it has been proposed to contribute to the pathogenesis of both chronic stable asthma and acute severe asthma. We have shown that in a model of chronic allergic asthma in mice, airway hyper-responsiveness (AHR) is independent of various Th2 cytokines and their signalling pathways, but is dependent on IFN-γ. In a model of an allergen-induced acute exacerbation of chronic asthma, we have demonstrated that activation of pulmonary macrophages may play a critical role in driving the inflammatory response. Furthermore, we have demonstrated that IFN-γ stimulation of macrophages can lead to steroidresistant airway inflammation and AHR via the production of interleukin-27. These findings strengthen the notion that the pathogenesis of the lesions of asthma, and especially of AHR, involves both Th2 and Th1 cytokines, as well as interaction between the allergic response and the innate host defence system. Targeting the effects of IFN-γ on pulmonary macrophages may be particularly relevant to the treatment of steroid-resistant acute exacerbations of asthma.

Tuberculosis is the second leading cause of infectious deaths globally. Many effective conventional antimycobacterial drugs have been available, however, emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) has overshadowed the effectiveness of the current first and second line drugs. Further, currently available agents are complicated by serious side effects, drug interactions and long-term administration. This has prompted urgent research efforts in the discovery and development of new anti-tuberculosis agent(s). Several families of compounds are currently being explored for the treatment of tuberculosis. This review article presents an account of the existing chemotherapeutics and highlights the therapeutic potential of emerging molecules that are at different stages of development for the management of tuberculosis disease.

Summary Early-life respiratory viral infections are linked to subsequent development of allergic asthma in children. We assessed the underlying immunological mechanisms in a novel model of the induction phase of childhood asthma. BALB/c mice were infected neonatally with pneumonia virus of mice, then sensitized intranasally with ovalbumin following recovery. Animals were challenged with low levels of aerosolized ovalbumin for 4 weeks to induce changes of chronic asthma, then received a single moderate-level challenge to elicit mild acute allergic inflammation. To inhibit the initial induction of a T helper type 2 (Th2) response, we administered neutralizing antibodies against interleukin (IL)-4 or IL-25, then assessed development of airway inflammation and remodelling. Anti-IL-4 administered during chronic challenge prevented development of chronic and acute allergic inflammation, as well as goblet cell hyperplasia/metaplasia, but features of remodelling such as subepithelial fibrosis and epithelial hypertrophy were unaffected. In contrast, anti-IL-25 had limited effects on the airway inflammatory response but prevented key changes of remodelling, although it had no effect on goblet cells. Both antibodies suppressed development of a Th2 response, while anti-IL-25 also promoted a Th17 response. In further experiments, anti-IL-25 was administered in early life alone, and again had limited effects on airway inflammation, but prevented development of airway wall remodelling. We conclude that in this murine model of childhood asthma, administration of anti-IL-4 or anti-IL-25 prevents development of some key features of asthma, suggesting that suppression of development of a Th2 response during the neonatal period or later in childhood could be effective for primary prevention.

Portfolios are an established method of assessment, although concerns do exist around their validity for capabilities such as reflection and self‐direction. This article describes an e‐portfolio which closely aligns learning and reflection to graduate capabilities, incorporating features that address concerns about portfolios. Students are required to complete assessments linked to graduate capabilities. In Year 3, a portfolio review occurs (205–248 students per year), focusing on students' grades and feedback from assessments and a reflective essay is submitted. In the essay, students reflect on their progress, identify areas of weakness and detail plans for improvement. Progress in each capability is summatively graded against specific criteria and feedback is provided. Students progressively accumulate evidence of learning linked to the graduate capabilities. The provision of sufficient structure prevents evasion of areas of weakness. Importantly, the equal weighting given to all graduate capabilities ...

We assessed the impact of educational strategies to reduce requests by junior medical officers for pathology laboratory investigations. We demonstrated a noticeable reduction in test requests following a campaign to encourage the use of a case-based online simulation tool. However, achieving an adequate participation rate and sustaining change were significant challenges.

Hepatitis C virus (HCV) infection is one of the major health problems worldwide. If left untreated, it leads to liver cirrhosis, liver cancer and death. Herein, we report synthesis and anti-HCV activity of a new class of pyrimidine nucleosides possessing a 4'-carboxymethyl (9-16, 21 and 23) or 4'-carboxamide function (17-19 and 24). Among these, 10-12 (EC50=33.1-42.4 μM), 14 and 21 (EC50=43.4-59.5 μM) exhibited potent activity in HCV-1a replicon cells without any toxicity to parent Huh-7 cells (CC50=>829-1055 μM). The anti-HCV activities demonstrated by this unusual class of compounds were superior to that of ribavirin (EC50=81.9 μM). Further, the most active analog, 12, was found to interact synergistically with ribavirin to inhibit HCV RNA replication.

Chronic infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) lead to serious liver diseases worldwide. Co-infection with HBV and HCV is very common and is associated with increased risk of liver pathogenesis, liver cancer, and liver failure. Several 5-substituted 3′-fluoro (or chloro) ( 1 – 4 , 6 , 7 , 17 – 19 ) and 2′,3′-difluoro 2′,3′-dideoxynucleosides ( 15 and 16 ) were synthesized and evaluated for in vitro antiviral activities against duck hepatitis B virus (DHBV), human hepatitis B virus, and hepatitis C virus. Of these compounds 4 , 7 , 17 , and 19 demonstrated moderate anti-HBV activity, and 2 , 4 , 7 , 8 , and 19 were weak inhibitors of HCV. Although 5-iodo derivative ( 7 ) was most inhibitory against HCV, it exhibited a reduction in cellular RNA levels in Huh-7 cells. The 5-hydroxymethyl-3′-fluoro-2′,3′-dideoxyuridine ( 4 ) and 1-(3-chloro-2,3-dideoxy-β- d - erythro -pentofuranosyl)-5-fluorouracil ( 19 ) provided the most inhibition of both viruses without cytotoxicity.

Hepatitis C virus (HCV) has the ability to persist in the majority of infected people. Strong, multispecific and sustained T-cell response is correlated with viral clearance. The mechanisms of chronicity by HCV are unclear. HCV could restrain the immune system and establish chronic infection by modulating dendritic cell (DC) function, T-cell function or both. DC dysfunction has been postulated to be either due to direct HCV infection or by the presence of HCV proteins. In this report, for the first time, we have examined whether soluble HCV proteins can impair DC function or directly inhibit T-cell responses in the cells obtained from healthy uninfected people. Our studies revealed that different HCV proteins used distinct mechanisms to down-regulate DC functions. Individual HCV proteins, Core, NS3, NS4, NS5 as well as fused Polyprotein (Core-NS3-NS4) were found to impair functions of both immature DCs and mature DCs by regulating the expression of co-stimulatory and antigen presentation molecules, strikingly reducing IL-12 secretion, inducing the expression of FasL to mediate apoptosis, interfering with allo-stimulatory capacity, inhibiting toll-like receptor signaling and inhibiting nuclear translocation of NFkappaB in DCs. Interestingly, HCV proteins did not directly inhibit T-cell proliferation. Our findings clearly demonstrate that HCV proteins impair T-cell responses indirectly by inhibiting DCs that could result in a sub-optimal cellular immune response allowing for persistent HCV infections. These studies delineate important mechanisms by which initial DC dysfunction can establish contributing to chronicity. Our data are in agreement with earlier observations that DCs are impaired in HCV infected people.

In higher education, most assessments or examinations comprise either multiple-choice items or open-ended questions such as modified essay questions (MEQs). Online concept and knowledge maps are potential tools for assessment, which might emphasize meaningful, integrated understanding of phenomena. We developed an online knowledge-mapping assessment tool, which provides automated feedback on student-submitted maps. We conducted a pilot study to investigate the potential utility of online knowledge mapping as a tool for automated assessment by comparing the scores generated by the software with manual grading of a MEQ on the same topic for a cohort of first-year medical students. In addition, an online questionnaire was used to gather students’ perceptions of the tool. Map items were highly discriminating between students of differing knowledge of the topic overall. Regression analysis showed a significant correlation between map scores and MEQ scores, and responses to the questionnaire regarding use of knowledge maps for assessment were overwhelmingly positive. These results suggest that knowledge maps provide a similar indication of students’ understanding of a topic as a MEQ, with the advantage of instant, consistent computer grading and time savings for educators. Online concept and knowledge maps could be a useful addition to the assessment repertoire in higher education.

Summary Background Airway hyperresponsiveness (AHR) in asthmatics includes a variable component that persists following an allergen challenge. This may be dissociated from inflammatory cell recruitment, implying a role for resident pulmonary cells in regulating the response. Objective Using improved methods of assessing AHR in a mouse model of allergic airway disease, to investigate the basis of the development of prolonged AHR. Method BALB/c mice were systemically sensitized and then challenged with aerosolized ovalbumin (OVA). Airway and tissue responsiveness were measured at baseline and at 1 day, and 1, 2 and 3 weeks after the last OVA challenge. Inflammatory cell numbers in BALF and levels of mRNA for eotaxin-1 and -2, IFN-γ, IL-5 and -13 in the lung were measured at each time-point. In further experiments, the roles of IFN-γ and of CCR3+ and CD4+ cells in the development of prolonged AHR were assessed by blockade or depletion with monoclonal antibodies. The role of pulmonary macrophages was assessed by selective chemical depletion of these cells. Results Airway responsiveness was increased above baseline at 1 day after the last OVA challenge, and this was sustained for 1 week. In contrast, tissue-specific responsiveness was only significantly increased above baseline at 1 day. Development of prolonged AHR was inhibited by neutralization of IFN-γ or by depletion of pulmonary macrophages, but not by depletion of either CD4+ T cells or CCR3+ eosinophils. Conclusion An interaction between IFN-γ and pulmonary macrophages contributed to the prolongation of airway hyperresponsiveness. In contrast, T cells and eosinophils did not contribute to prolongation of AHR. These findings emphasize the importance of the innate host response in the development of manifestations of asthma, as well as its potential relevance as a target for therapeutic intervention. Cite this as: M. Yang, R. K. Kumar and P. S. Foster, Clinical & Experimental Allergy, 2010 (40) 163–173.

The Ym1/2 lectin is expressed abundantly in the allergic mouse lung in an IL-13-dependent manner. However, the role of Ym1/2 in the development of allergic airways disease is largely unknown. In this investigation, we show that treatment of mice with anti-Ym1/2 Ab during induction of allergic airways disease attenuated mediastinal lymph node production of IL-5 and IL-13. Ym1/2 was found to be expressed by dendritic cells (DCs) in an IL-13-dependent manner and supplementation of DC/CD4+ T cell cocultures with Ym1/2 enhanced the ability of IL-13−/− DCs to stimulate the secretion of IL-5 and IL-13. Affinity chromatography identified 12/15(S)-lipoxygenase (12/15-LOX) as a Ym1/2-interacting protein and functional studies suggested that Ym1/2 promoted the ability of DCs to stimulate cytokine production by inhibiting 12/15-LOX-mediated catalysis of 12-hydroxyeicosatetraenoic acid (12(S)-HETE). Treatment of DC/CD4+ T cell cultures with the 12/15-LOX inhibitor baicalein enhanced, whereas 12(S)-HETE inhibited the production of Th2 cytokines. Notably, delivery of 12(S)-HETE to the airways of mice significantly attenuated the development of allergic airways inflammation and the production of IL-5 and IL-13. In summary, our results suggest that production of Ym1/2 in response to IL-13 promotes Th2 cytokine production and allergic airways inflammation by inhibiting the production of 12(S)-HETE by 12/15-LOX.

Chronic inflammation and airway hyperresponsiveness (AHR) in asthmatics are usually managed effectively by treatment with glucocorticoids. However, a subset of patients remains refractory to therapy. The underlying mechanisms are largely unknown, although recruitment of neutrophils (rather than eosinophils) is strongly correlated, suggesting a role for nonallergic host defense responses. Increased levels of IFN-γ and endotoxins are also related to severe asthma and because these activate host defense pathways, we investigated a possible common etiologic link to steroid-resistant disease. To be able to unravel the complexity of asthmatic inflammation, we used two model systems which permitted dissection of the relevant molecular pathways. In the first of these, we transferred transgenic OVA323–339 peptide-specific IFN-γ-producing Th1 cells into mice. These animals were subsequently challenge via the airways with OVA323–339 peptide and/or LPS. Challenge with both components, but not with either one individually, induced AHR. Importantly, AHR was resistant to treatment with dexamethasone. Development of AHR was dependent on IFN-γ, inhibited by depletion of pulmonary macrophages (but not neutrophils) and abrogated in TLR4- or MyD88-deficient mice. In contrast, in the second model in which we transferred OVA323–339 peptide-activated Th2 cells, eosinophilic inflammation and AHR were induced, and both were suppressed by steroid treatment. We conclude that cooperative signaling between IFN-γ and TLR4/MyD88 constitutes a previously unrecognized pathway that regulates macrophage-dependent steroid-resistant AHR.