MacEwan Open Journals (MacEwan University)
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Examining Correlates and Consequences of Implicit Theories of Social Anxiety
No full textA small but growing literature concerns the application of implicit theories (i.e., incremental and entity mindsets regarding the stability or malleability of attributes, respectively) to disorders and their symptoms. Implicit theories of social anxiety were explored through a cross-sectional study (N =274 undergraduate participants) examined correlations among implicit theories of social anxiety and social anxiety symptoms, emotional regulation, help-seeking, and behavioural engagement. As predicted, incremental mindsets were correlated with lower social anxiety, greater use of emotional reappraisal, more help-seeking behaviour, greater behavioural activation and less behavioural inhibition. In a regression analysis, incremental mindsets predicted social anxiety symptoms above and beyond the remaining variables. Overall, the current findings warrant additional research of implicit theories of social anxiety, in clinical populations with social anxiety disorder to determine if the found correlates will be replicated and exacerbated within a clinical population.
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Mental tug of war: How does grasping and language affect each other?
No full textPrevious studies have found an association between hand motor actions and speech function. The objective of this study was to investigate if verbal fluency tasks (word production) can affect grasping behaviour. We reasoned that the type of word would influence grasping behaviour differentially. Specifically, we hypothesized that when compared to nouns, the generation of verbs would interfere more with grasping because previous research has shown activation in primary motor cortex during verb comprehension. We recruited left- (n=15) and right-handers (n=24) to participate in this study.
Each participant was asked to perform a grasping task (LEGO building task), and a word fluency task both separately and simultaneously. The word fluency tasks consisted of noun and verb generation. Our results showed that overall, the number of times participants incorrectly grasped a block (place errors) while simultaneously producing verbs predicted the number of verbs produced while building; the more place errors made, the fewer verbs produced. This was not the case when producing nouns. To conclude, speech production, specifically of verbs interfere with manual action.
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The Effects of Adolescent WIN-55 Exposure: Assessing Changes in Neuroanatomy and Social Behaviour in Rats
No full textThe effect of cannabis on adolescent development is a topical and socially relevant issue, as several states have moved to legalize its use, and with Canada seeming to follow suit. Previous work in this field has found that adolescent exposure to cannabis can lead to deficits in the development of higher-level brain functions like attention and working memory (Ehrenreich et al., 1999). Because of the implication of cannabis exposure on the development of the adolescent brain, particularly regarding executive function skills, we believe studying play will serve as a benchmark from which we can begin to assess these changes. In order to do so, this study utilized WIN-55, a THC analogue and endocannabinoid (CB1) agonist that elicits comparable effects to those displayed following THC exposure (Schneider and Koch, 2003).
Over the course of this study, animals were exposed to a daily dose of 0.3 mg/kg WIN-55, or a saline control for 10 days during puberty. Dosing encompassed postnatal day (P) 22-32 for females and P32-42 for males. We hypothesized that this dosing paradigm would be sufficient to elicit changes in the behaviour, ultrasonic vocalizations and neuroanatomy of the affected animals. Following the final injection, animals were socially isolated from their cage mate for 24hrs to encourage playful interaction during behavioural testing. The animals were then paired with their cage mate and placed in a dark, soundproof chamber where audio and video were recorded for 10 minutes. This procedure was replicated the following day so as to record a second day of behavioural analysis. Following all behavioural testing the animals were sacrificed and their brains extracted for anatomical analysis. Measures of neuroanatomy included thalamic volume and cortical thickness measurements, which were taken from selected planes of the brain.
Stereological analysis was conducted on two frontal regions of the brain, AID and Cg3, which contribute to higher brain functioning. Adolescent play behaviour was recorded over peak-play periods and was analysed to reveal a significant decrease in the number of interactions between affected males. Ultrasonic vocalization analysis also revealed significant decreases in the number of calls exhibited in affected males.
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The role of eukaryotic initiation factor 5B (eIF5B) in cell cycle regulation
No full textGene expression is critically regulated at the transcriptional, translational, and post-translational levels. Dysregulation and altered mechanisms of translational control have significant consequences in processes including cell growth, cell death, cell proliferation, and maturation. Initiation is the rate- limiting step of translation, which is inhibited under physiological stress conditions. During the integrated stress response, the α subunit of eukaryotic initiation factor 2 (eIF2) is phosphorylated. This phosphorylation attenuates general translation, by preventing the reformation of the necessary ternary complex. Despite the attenuation of general translation, certain mRNAs containing upstream open reading frames (uORFs) are favorably translated during this condition. uORFs are mRNA elements with a start codon in the 5’ UTR that is out-of-frame with the main coding sequence. Bioinformatic studies have shown 49% of human transcripts to contain uORFs.
Preliminary data suggests that the depletion of eIF5B parallels the effects of phosphorylation of eIF2α. eIF5B depletion has been observed to inhibit global translation, while enhancing the translation of certain uORF-containing mRNAs. The Thakor lab has shown the protein p27 to be upregulated when eIF5B is knocked down in U343 (human glioblastoma multiforme) cells. As p27 is a cyclin-dependent kinase inhibitor (CKI), which controls cell progression from the G1 to S phase, this suggests a significant role for eIF5B in the cell cycle. However, eIF5B depletion has been observed to not have significant effects on the cyclin-dependent kinase inhibitor: p21. Further, PI staining and flow cytometric analysis have demonstrated that eIF5B does not have any significant effects on the cell cycle. This data suggests that eIF5B has a significant role in the regulation of p27, but does not contribute to cell cycle regulation.
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The effects of molecular crowding on the kinetics and small molecule inhibition of alkaline phosphatase
No full textEnzymes have adapted to function in complex environments crowded with many other solutes. To get a better understanding of in vivo crowding, we used polyethylene glycol (MW 8000) and dextran (MW 6000) as in vitro crowding agents and observed their effects both the kinetics of alkaline phosphatase-catalyzed para-nitrophenyl phosphate hydrolysis and the inhibition of this reaction by competitive and uncompetitive inhibitors. Reaction kinetics were followed using UV-visible spectrometry and the initial rate was analyzed using Michaelis-Menten kinetics to arrive at an apparent Vmax and Km for each reaction condition. We observed that polyethylene glycol increased Vmax while a similar amount of dextran strongly reduced Vmax. Crowding by these agents also significantly altered the effectiveness of small-molecule inhibitors and suggests that the action of drugs can be different going from “bench” research to “bedside” application.
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Identification and Alignment of Human and Mouse SNPs in the DMD Gene using a Bioinfomatical Approach
No full textMuscular dystrophy (MD) is a fatal, muscle wasting disease affecting individuals who have acquired a mutation in their dystrophin (DMD) gene. Some of these mutations are a single nucleotide alteration. Dystrophin is a vital part of a protein complex in skeletal and cardiac muscle tissue. The gene is the largest in the human genome, spanning 79 exons on the X chromosome. MD is X linked dominant, targeting mostly males that are affected by the one of the two most common forms, Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). Both DMD and BMD result from single nucleotide polymorphisms (SNPs). To date, there is no cure for the disease. Of the identified SNP mutations, the phenotype for many has not yet been characterized. To this end, identifying conserved regions between humans and mice would allow for further characterization of these SNPs, as dystrophinin in mice is functionally analogous. Therefore, I hypothesize that some of the human SNPs in DMD are conserved in mouse DMD. Using a bioinformatical approach, I collected various SNP mutations, and using Ensemble, I then aligned the genes. Of the exons examined, 212 SNPs were identified, 17 of which were on exon 57. Furthermore, many of the human SNPs align with mouse DMD gene SNPs. This study will allow for further characterization of the DMD SNPs, as well as serve as a platform for future in vivo studies, opening opportunities to possible gene therapies for individuals with muscular dystrophy
The Effect of Varying Doses of UVC Radiation on the Viability of Human Cancer Cells
No full textUVC radiation has the ability to damage DNA in cells. This causes the cell to either arrest division or undergo apoptosis. In this study we observed the effects of increasing doses of UVC radiation on the division rates and viability of cells from the human cancer cell line MCF7. We hypothesized that at a certain dose the cells would no longer be able to repair DNA and apoptosis would be induced. Furthermore, we hypothesized that the division rate would decrease as the dose of UVC increased. Cells were irradiated at either, 0 mJ/cm2 (negative control), 0.31 mJ/cm2, 1.55 mJ/cm2, 4.65 mJ/cm2, 9.3 mJ/cm2, 18.6 mJ/cm2, 37.2 mJ/cm2, or 74.4 mJ/cm2. 48 hours after irradiation, a Trypan Blue viability assay was performed to determine the percentage of dead cells at each dose. To compare division rates, the total number of cells in each treatment was taken as a percentage of the total number of non- treated cells. The IC50 for apoptosis was found to be 21.25 mJ/cm2. Our results showed that the total number of cells decreased significantly between 0 mJ/cm2, and 4.65 mJ/cm2. At concentrations above 4.65 mJ/cm2, the total number of cells remained constant. Suggesting that this is the point in which cells may have stopped growing. In contrast, the percentage of dead cells did not differ between the nontreated cells and those treated with UVC doses up to 9.3 mJ/cm2, but was significantly higher at doses above 18.6 mJ/cm2. The point at which the percentage of dead cells begins to increase significantly and where division rates plateau is relatively close, thus, we infer that this the point in which cells stopped trying to repair their DNA and instead began to undergo apoptosis. As we hypothesized, at a high enough dose, the DNA in cells would become irreparable and the cells would die. Because all cells above this dose show significant death, the observation is consistent with our hypothesis.
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Maternal Preconception Nicotine and Enriched Housing: The Effects on Offspring Anxiety Behaviour
No full textA mother’s environment can affect her offspring even before conception. Both positive factors, such as an enriched environment, and negative factors, such as drug use, have the potential to shape offspring development. The influence of psychoactive drugs is especially concerning because of the role they play in modulating important survival instincts, such as anxiety; therefore, strategies to counteract the changes induced by drug use are of particular interest. One possible way to counteract the transgenerational effects of drugs may be through enriching the maternal environment, which has been previously shown to attenuate the effects of nicotine. Enriched environments have huge beneficial effects on individuals, and hopefully these benefits can be passed down to offspring as a protective factor. In this experiment, female rats received moderate levels of nicotine in their drinking water (15mg/L sweetened with 1% sucralose) while being housed in either standard lab conditions or an enriched environment. The rats undergoing enriched housing were placed in a larger cage with multiple levels, more cage mates, and a rotation of stimulating objects. Control females received water sweetened with 1% sucralose while living in either environment. The offspring underwent behavioural testing in adolescence and adulthood to look for changes in elevated plus maze behaviours, a test that measure anxiety-like behaviours. Cortical thickness and thalamic size were also examined to look for effects on brain morphology. The results showed significant effects of preconception nicotine and enriched housing in the anxiety-like behaviours of the offspring in both adolescence and adulthood, dependent on sex. Results suggest that maternal preconception nicotine use lowers the amount of anxiety present in offspring. When the mothers are kept in enriched housing, however, the anxiety levels in the nicotine cohort return to levels near that of the control group. These results have important implications in the ability of the offspring to survive their environment, as differences in anxiety levels affect the survival strategies used by the offspring. Additionally, the return to control levels in the offspring whose mothers lived in an enriched environment does in fact suggest that maternal enrichment acts as a protective factor against preconception nicotine use. These results are not surprising as nicotinic acetylcholine receptors play a major role in the modulation of anxiety pathways, evidenced by both increases and decreases in anxiety due to nicotine use
The Over-Incarceration of Indigenous Women: A Look at Meeting Needs in Community Organizations
No full textIndigenous women make up a disproportionate percentage of incarcerated women in Canada. The effects of settler-colonialism are ever present, as these women experience marginalized lives. The violence they experience is twofold – in their everyday lives and in prison. This study is grounded in penal abolitionism and explores how the needs of Indigenous women in trouble are being met within the community – keeping them out of contact with the criminal justice system. I look at community organizations within Edmonton through a content analysis of website and Facebook data, analyzing the discourse for emerging themes related to identifying and attending to social and economic needs. While the organizations are virtuous in their intent, I find that they are an extension of and strengthen the values of settler-colonialism in assimilative ways. I draw on Foucault’s work on ‘docile bodies’ and G. Coulthard’s work on the ‘liberal politics of recognition’ to situate my analysis that Indigenous women are being disciplined and produced through incarceration and community organizations, thus increasing their utility in society. Community organizations that attend to the needs of Indigenous women have been designed and formulated within a society that is predicated on settler-colonialism. In order for Indigenous women to have their needs met, the Indigenous community must be a self-determining sovereign body.
Discipline: Sociology
Faculty Mentor: Dr. Amanda Nelun
The Portrayal of Climate Change in the Edmonton Journal
No full textThe presentation will detail the results of a content analysis of Edmonton Journal articles that examines the publication\u27s portrayal of climate change from 2013 - 2016. Articles were coded for valence (whether climate change was portrayed positively or negatively), voice (which actors were given the opportunity to discuss the issue), scope (if the issue was emphasized as being a local versus global problem), skepticism (support versus denial of climate change as being an issue), and responsibility (who should be acting to resolve the climate change issue). Results for valence, responsibility, and skepticism will be discussed autonomously, but also within the context of current political attitudes in North America regarding climate change. Limitations of the study as well as ideas and implications for future research will also be addressed. Content analysis research began as an independent study and was completed with the USRI grant under the supervision of Dr. Shelley Boulianne.
Discipline: Psychology
Faculty Mentor: Dr. Shelley Bouliann