Measuring Changes in Brain Metabolite Levels Using Live-animal Magnetic Resonance Spectroscopy and Offline LC-MS Metabolomics in a Binge-ethanol Murine Model

Alcoholism and acute alcohol binge are significant public health concerns. Liquid chromatography-mass spectrometry (LC-MS) based metabolomics is a robust and sensitive technique for determining and quantifying transient or permanent biochemical changes within the central nervous system (CNS). However, access to human tissue and CNS biofluid for such analyses is limited in a clinical context. In-vivo magnetic resonance spectroscopy (MRS) is an attractive alternative for clinical measurement but currently the technique is limited to a small to a number of well-characterized, highly abundant analytes. We therefore seek to correlate LC-MS and MRS measurements to better understand and leverage the strengths of each. Following live animal MRS measurement, metabolites in hippocampal brain punch homogenates were quantified by LC-MS, and a Spearman’s correlation coefficient was calculated. We found that the measurements for glutamine and glutamate,, were significantly correlated. Other established neurochemicals, including NAA and aspartate, showed non-significant correlations. NAAG showed little correlation between the two measurements. Additional experiments are ongoing to resolve these discrepancies, and determine how to achieve better agreement between the two methods. In addition,, we used Elements (Proteome Software) to determine differentially expressed metabolites between ethanol exposed and control mice.. An initial pass shows more than 1000 peak-picked features identified in the two conditions, with approximately 200 analytes identified in the metabolite database (human) based on accurate mass. Differentially expressed candidates can be validated further using tandem mass spectrometry and, where possible, the use of authentic standards. Metabolites that change after binge ethanol exposure are reported along with an overview of comparing MRS with LC-MS datasets

Phosphorylation of histone H3(T118) alters nucleosome dynamics and remodeling

Nucleosomes, the fundamental units of chromatin structure, are regulators and barriers to transcription, replication and repair. Post-translational modifications (PTMs) of the histone proteins within nucleosomes regulate these DNA processes. Histone H3(T118) is a site of phosphorylation [H3(T118ph)] and is implicated in regulation of transcription and DNA repair. We prepared H3(T118ph) by expressed protein ligation and determined its influence on nucleosome dynamics. We find H3(T118ph) reduces DNA–histone binding by 2 kcal/mol, increases nucleosome mobility by 28-fold and increases DNA accessibility near the dyad region by 6-fold. Moreover, H3(T118ph) increases the rate of hMSH2–hMSH6 nucleosome disassembly and enables nucleosome disassembly by the SWI/SNF chromatin remodeler. These studies suggest that H3(T118ph) directly enhances and may reprogram chromatin remodeling reactions

The killer within: Endogenous bacteria accelerate oyster mortality during sustained anoxia

16 pages, 5 figures, 2 tablesSustained periods of anoxia, driven by eutrophication, threaten coastal marine systems and can lead to mass mortalities of even resilient animals such as bivalves. While mortality rates under anoxia are well-studied, the specific mechanism(s) of mortality are less clear. We used a suite of complementary techniques (LT50, histology, 16S rRNA amplicon sequencing, and valvometry) to show that the proliferation of anaerobic bacteria within eastern oysters (Crassostrea virginica) accelerates mortality rate under anoxic conditions. Manipulative laboratory experiments revealed that oyster survival under anoxic conditions was halved when bacteria were present compared to when they were excluded by the broad-spectrum antibiotic chloramphenicol. Histological assessments supported this mechanism and showed infiltration of bacteria in oysters that were not treated with antibiotics compared to a general lack of bacteria when oysters were treated with antibiotics. 16S rRNA amplicon sequencing failed to identify any particular genera of bacteria responsible for mortality, rather a diversity of endogenous anaerobic and/or sulfate-reducing bacteria were common among oysters. In addition, monitoring of oyster valve gaping behavior in the field revealed that oysters showed remarkable valve closure synchrony when first exposed to anoxia. However, oysters periodically opened throughout anoxia/hypoxia in both the lab and field, suggesting that the infiltration of exogenous bacteria from the environment may also influence mortality rates under natural settings. Coupled with previous studies, we posit that mass mortality events in a wide range of coastal bivalves are likely the result of co-morbidity from asphyxiation and bacterial processesThis study was funded by L'Étang Ruisseau Bar Ltd. in partnership with the Department of Fisheries and Oceans of Canada (Aquaculture Collaborative Research and Development Program, project 17-G-02 led by M.R.S.C.), a NSERC Discovery Grant to R.F. (RGPIN-2017-04294), and a Total Development Fund from the New Brunswick Department of Agriculture, Aquaculture and Fisheries to R.F.Peer reviewe

The environmental profile of a community’s health: a cross-sectional study on tobacco marketing in 16 countries.

OBJECTIVE: To examine and compare tobacco marketing in 16 countries while the Framework Convention on Tobacco Control requires parties to implement a comprehensive ban on such marketing. METHODS: Between 2009 and 2012, a kilometre-long walk was completed by trained investigators in 462 communities across 16 countries to collect data on tobacco marketing. We interviewed community members about their exposure to traditional and non-traditional marketing in the previous six months. To examine differences in marketing between urban and rural communities and between high-, middle- and low-income countries, we used multilevel regression models controlling for potential confounders. FINDINGS: Compared with high-income countries, the number of tobacco advertisements observed was 81 times higher in low-income countries (incidence rate ratio, IRR: 80.98; 95% confidence interval, CI: 4.15-1578.42) and the number of tobacco outlets was 2.5 times higher in both low- and lower-middle-income countries (IRR: 2.58; 95% CI: 1.17-5.67 and IRR: 2.52; CI: 1.23-5.17, respectively). Of the 11,842 interviewees, 1184 (10%) reported seeing at least five types of tobacco marketing. Self-reported exposure to at least one type of traditional marketing was 10 times higher in low-income countries than in high-income countries (odds ratio, OR: 9.77; 95% CI: 1.24-76.77). For almost all measures, marketing exposure was significantly lower in the rural communities than in the urban communities. CONCLUSION: Despite global legislation to limit tobacco marketing, it appears ubiquitous. The frequency and type of tobacco marketing varies on the national level by income group and by community type, appearing to be greatest in low-income countries and urban communities

The environmental profile of a community's health: a cross-sectional study on tobacco marketing in 16 countries.

OBJECTIVE: To examine and compare tobacco marketing in 16 countries while the Framework Convention on Tobacco Control requires parties to implement a comprehensive ban on such marketing. METHODS: Between 2009 and 2012, a kilometre-long walk was completed by trained investigators in 462 communities across 16 countries to collect data on tobacco marketing. We interviewed community members about their exposure to traditional and non-traditional marketing in the previous six months. To examine differences in marketing between urban and rural communities and between high-, middle- and low-income countries, we used multilevel regression models controlling for potential confounders. FINDINGS: Compared with high-income countries, the number of tobacco advertisements observed was 81 times higher in low-income countries (incidence rate ratio, IRR: 80.98; 95% confidence interval, CI: 4.15-1578.42) and the number of tobacco outlets was 2.5 times higher in both low- and lower-middle-income countries (IRR: 2.58; 95% CI: 1.17-5.67 and IRR: 2.52; CI: 1.23-5.17, respectively). Of the 11,842 interviewees, 1184 (10%) reported seeing at least five types of tobacco marketing. Self-reported exposure to at least one type of traditional marketing was 10 times higher in low-income countries than in high-income countries (odds ratio, OR: 9.77; 95% CI: 1.24-76.77). For almost all measures, marketing exposure was significantly lower in the rural communities than in the urban communities. CONCLUSION: Despite global legislation to limit tobacco marketing, it appears ubiquitous. The frequency and type of tobacco marketing varies on the national level by income group and by community type, appearing to be greatest in low-income countries and urban communities

Le musée, un lieu éducatif

This anthology contains essays on various aspects of museum education, by 35 members of the Special Interest Group on Education and Museums (SIGEM). Originally presented at a conference held in Montreal in 1995, the essays in this book address a wide range of issues related to the educational function of museums. Topics discussed include: educational, scientific and museological research; the value of guided tours and visual arts workshops; the question of evaluation; and relationships between museums and schools. 21 diagrams and 19 charts. 4 texts in English 31 texts in French. Circa 480 bibl. ref

2017 Research & Innovation Day Program

A one day showcase of applied research, social innovation, scholarship projects and activities.https://first.fanshawec.ca/cri_cripublications/1004/thumbnail.jp