Isolation, characterisation and experimental evolution of phage that infect the horse chestnut tree pathogen, Pseudomonas syringae pv. aesculi

Bleeding canker of horse chestnut trees is a bacterial disease, caused by the bacterium Pseudomonas syringae pv. aesculi, estimated to be present in ~ 50% of UK horse chestnut trees. Currently, the disease has no cure and tree removal can be a common method of reducing inoculum and preventing spread. One potential method of control could be achieved using naturally occurring bacteriophages infective to the causative bacterium. Bacteriophages were isolated from symptomatic and asymptomatic horse chestnut trees in three locations in the South East of England. The phages were found to be belonging to both the Myoviridae and Podoviridae families by RAPD PCR and transmission electron microscopy. Experimental coevolution was carried out to understand the dynamics of bacterial resistance and phage infection and to determine whether new infective phage genotypes would emerge. The phages exhibited different coevolution patterns with their bacterial hosts across time. This approach could be used to generate novel phages for use in biocontrol cocktails in an effort to reduce the potential emergence of bacterial resistance

Effects of virus infection on release of volatile organic compounds from insect-damaged bean, Phaseolus vulgaris

Insects can serve as important vectors of plant pathogens, especially viruses. Insect feeding on plants causes the systemic release of a wide range of plant volatile compounds that can serve as an indirect plant defense by attracting natural enemies of the herbivorous insect. Previous work suggests that the Mexican bean beetle (Epilachna varivestis) prefers to feed on plants infected by either of two viruses that it is known to transmit: Southern bean mosaic virus (SBMV) or Bean pod mottle virus (BPMV). A possible explanation for the preferred feeding on virus-infected tissues is that the beetles are attracted by volatile signals released from leaves. The purpose of this work was to determine whether volatile compounds from virus-infected plants are released differentially from those emitted by uninfected plants. To test the hypothesis, common bean plants (Phaseolus vulgaris cv. Black Valentine) were inoculated with either BPMV, SBMV, or a mixture of both viruses, and infected plants were compared to uninfected plants. An Ouchterlony assay was used with SBMVand BPMV-specific antisera to confirm the presence of virus in inoculated plants. RNA blot analysis was performed on tissue from each plant and indicated that a well-characterized defense gene, encoding phenylalanine ammonia-lyase (PAL), was not induced in systemic tissue following virus infection. Plant volatiles were collected—and analyzed via gas chromatography (GC)—from plants that were either undamaged or beetle-damaged. In undamaged plants, there were no measurable differences in profiles or quantities of compounds released by uninfected and virus-infected plants. After Mexican bean beetles were allowed to feed on plants for 48 h, injured plants released several compounds that were not released from undamaged plants. Lower quantities of volatile compounds were released from virus-infected plants suggesting that enhanced release of plant-derived volatile organic compounds is not the cause for attraction of Mexican bean beetles to virus-infected plants

Effect of a University Physical Activity Challenge on Levels of Anxiety, Depression, Stress, and Perceived Dependency of Wearing a Physical Activity Tracker

Many studies have researched the benefits of physical activity (PA) and well-being, leading many universities to promote PA on campus. There is limited research on how university-based PA promotion impacts mental health, as well as the impact of wearing a physical activity tracker (PAT) and its potential to create dependency on wearing the device. PURPOSE: To understand the effects of a 4-week campus-wide PA challenge on levels of anxiety, depression, and stress in college students, and the potential dependency effects of wearing a PAT. METHODS: For the duration of the 4-week challenge, 44 undergraduate and 6 graduate students (μ = 21.4 years) wore a PAT with limited feedback, and answered questionnaires regarding their anxiety, depression, stress, and their perceived PAT dependency at the beginning, middle, end, and two weeks post-challenge. RESULTS: The results indicate that anxiety, depression, and stress did not change across time. Interestingly, significant interactions were revealed, such that individuals who wore a PAT (PAT Users) before the study differed in their perceived dependency on wearing an activity tracker compared to those who did not wear one prior to the study (PAT Non-users). Differences between PAT Users and PAT Non-users occurred when asked if they would modify their behavior due to the absence of the tracker, and the degree to which they attributed their PA engagement to be driven by needing it to be counted on the PAT. CONCLUSION: Further analyses need to be conducted to determine if the challenge led to changes in PA behavior, and explore if those changes were related to changes in anxiety, depression, and stress, as well as PAT dependency. Future research should continue to explore the psychological consequences of wearing a PAT to better understand the potential dependence effects that can occur

Chapter 11: Teaching mathematics to students with disabilities from diverse backgrounds

According to the Organization for Economic Cooperation and Development (OECD), the literacy and numeracy skills that are distributed across a population will have significant impact on economic and social outcomes. In particular, the “higher the levels of inequality in literacy and numeracy skills … the greater the inequality of distribution of income” (OECD, 2013, p. 26). However, although literacy skills are important, it has been suggested that poor mathematical skills may be more of a handicap than poor literacy skills, especially in the workplace (Butterworth, 2005; McCloskey, 2007). As McCloskey (2007) notes, “… quantitative concepts and information are involved in many facets of home, work and community life …” (p. 421). Poor quantitative skills are likely to pose significant problems in everyday life, even into adulthood (Dougherty, 2003; McCloskey, 2007)

“Because we have really unique art”: Decolonizing Research with Indigenous Youth Using the Arts

Indigenous communities in Canada share a common history of colonial oppression. As a result, many Indigenous populations are disproportionately burdened with poor health outcomes, including HIV. Conventional public health approaches have not yet been successful in reversing this trend. For this study, a team of community- and university-based researchers came together to imagine new possibilities for health promotion with Indigenous youth. A strengths-based approach was taken that relied on using the energies and talents of Indigenous youth as a leadership resource. Art-making workshops were held in six different Indigenous communities across Canada in which youth could explore the links between community, culture, colonization, and HIV. Twenty artists and more than 85 youth participated in the workshops. Afterwards, youth participants reflected on their experiences in individual in-depth interviews. Youth participants viewed the process of making art as fun, participatory, and empowering; they felt that their art pieces instilled pride, conveyed information, raised awareness, and constituted a tangible achievement. Youth participants found that both the process and products of arts-based methods were important. Findings from this project support the notion that arts-based approaches to the development of HIV-prevention knowledge and Indigenous youth leadership are helping to involve a diverse cross-section of youth in a critical dialogue about health. Arts-based approaches represent one way to assist with decolonization for future generations

Differential effects of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 on atherosclerosis and monocyte/macrophage invasion

AIMS: MMPs contribute to atherosclerotic plaque progression and instability, but the relative potency of their endogenous tissue inhibitors of metalloproteinases (TIMPs) as protective factors has not been defined. We therefore investigated the impact of TIMP-1 and TIMP-2 knockout on atherosclerotic plaque burden and composition in apolipoprotein E-knockout (Apoe(−/−)) mice and studied the underlying effects on monocyte/macrophage behaviour. METHODS AND RESULTS: Analysis of brachiocephalic artery plaques revealed comparable atherosclerotic lesion areas between TIMP-1(−/−) Apoe(−/−) or TIMP-2(−/−) Apoe(−/−) double deficient mice and relevant age-matched, strain-matched Apoe(−/−) controls after 8 weeks of high-fat feeding. However, lesions from TIMP-2(−/−) Apoe(−/−) mice had higher levels of markers associated with plaque vulnerability, including increased macrophage: vascular smooth muscle cell ratios, larger necrotic core areas, reduced collagen contents, increased macrophage proliferation, and apoptosis frequencies, compared with TIMP-1(−/−)Apoe(−/−) and controls. In contrast, TIMP-1(−/−) Apoe(−/−) animals only had a significant reduction in vascular smooth muscle cell content compared with Apoe(−/−) controls. In vitro and in vivo findings implicated heightened monocyte/macrophage invasion in the detrimental effects observed on atherosclerotic plaque composition in TIMP-2(−/−) Apoe(−/−) mice. Moreover, TIMP-2 specifically decreased MMP-14-dependent monocyte/macrophage infiltration into sites of experimentally induced inflammation and established atherosclerotic lesions. CONCLUSION: Our data demonstrate that TIMP-2 plays a greater protective role than TIMP-1 during the pathogenesis of atherosclerosis, in part by suppressing MMP-14-dependent monocyte/macrophage accumulation into plaques

Disparate Effects of MMP and TIMP Modulation on Coronary Atherosclerosis and Associated Myocardial Fibrosis

Matrix metalloproteinase (MMP) activity is tightly regulated by the endogenous tissue inhibitors (TIMPs), and dysregulated activity contributes to extracellular matrix remodelling. Accordingly, MMP/TIMP balance is associated with atherosclerotic plaque progression and instability, alongside adverse post-infarction cardiac fibrosis and subsequent heart failure. Here, we demonstrate that prolonged high-fat feeding of apolipoprotein (Apo)e-deficient mice triggered the development of unstable coronary artery atherosclerosis alongside evidence of myocardial infarction and progressive sudden death. Accordingly, the contribution of select MMPs and TIMPs to the progression of both interrelated pathologies was examined in Apoe-deficient mice with concomitant deletion of Mmp7, Mmp9, Mmp12, or Timp1 and relevant wild-type controls after 36-weeks high-fat feeding. Mmp7 deficiency increased incidence of sudden death, while Mmp12 deficiency promoted survival, whereas Mmp9 or Timp1 deficiency had no effect. While all mice harboured coronary disease, atherosclerotic burden was reduced in Mmp7-deficient and Mmp12-deficient mice and increased in Timp1-deficient animals, compared to relevant controls. Significant differences in cardiac fibrosis were only observed in Mmp-7-deficient mice and Timp1-deficient animals, which was associated with reduced capillary number. Adopting therapeutic strategies in Apoe-deficient mice, TIMP-2 adenoviral-overexpression or administration (delayed or throughout) of a non-selective MMP inhibitor (RS-130830) had no effect on coronary atherosclerotic burden or cardiac fibrosis. Taken together, our findings emphasise the divergent roles of MMPs on coronary plaque progression and associated post-MI cardiac fibrosis, highlighting the need for selective therapeutic approaches to target unstable atherosclerosis alongside adverse cardiac remodelling while negating detrimental adverse effects on either pathology, with targeting of MMP-12 seeming a suitable target

Predicting Falls in Community-Dwelling Older Adults Using the Repetitive Step Test

Background/Purpose: The Repetitive Step Test (RST) is a newly developed dynamic balance test that requires stepping in multiple directions. It has previously demonstrated excellent test-retest and inter-rater reliability, along with ability to retrospectively classify individuals who had fallen more than once in 12 months though its ability to predict falls has not been evaluated. This study aimed to determine the capability of the RST to identify individuals likely to fall prospectively over 12 months. Methods: 63 community-dwelling adults \u3e65 years old were tested using the following balance and mobility measures: RST, 10 Meter Walk Test (10MWT), Activities-specific Balance Confidence scale (ABC), Four Square Step Test (FSST), and Timed Up and Go (TUG). For the RST, participants completed as many steps as possible in 15 seconds at 50% and 75% of their right leg length in the anterolateral and posterolateral directions bilaterally. Participants completed a fall log that was reported on a monthly basis for 12 months. Results: Based on 12 months of data, receiver operating characteristic (ROC) curve analysis was used to compare adults who fell \u3e 2 times to adults (n=17) who did not fall (n=29). Area under the curve (AUC) results with 95% confidence interval are as follows: RST at 50% 0.40 (0.22-0.58), RST at 75% 0.41 (0.24-0.57), FSST 0.45 (0.28-0.62), TUG 0.49 (0.32-0.66), ABC 0.61 (0.44-0.78) and 10MWT 0.67 (0.51-0.83). Conclusion: At 12 months, the RST and other balance and mobility measures either failed to or poorly predicted the number of falls. Research is needed to determine how to best predict falls in this population, and whether any single balance test can effectively identify individuals who are most likely to fall. Clinical Relevance: Currently, there is no simple measure of balance and mobility that can accurately predict falls in community-dwelling older adults. The RST was ineffective in predicting falls at 12 months. Given the unique characteristics of the RST, it may still be a useful tool for assessing and monitoring bilateral lower extremity performance and stepping ability, especially in individuals who present with asymmetrical impairments (e.g., stroke, multiple sclerosis, Parkinson’s disease).https://ecommons.udayton.edu/dpt_symposium/1005/thumbnail.jp