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2012

Western University

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Full-Text Articles in Life Sciences

Genome Profiling Of Two Strains Of The Green Alga Chlamydomnas Raudensis, Rajesh Kumar Gupta Dec 2012

Genome Profiling Of Two Strains Of The Green Alga Chlamydomnas Raudensis, Rajesh Kumar Gupta

Electronic Thesis and Dissertation Repository

Chlamydomonas raudensis Ettl consists of two strains, SAG 49.72 and UWO 241. They have identical Internal Transcribed Spacer sequences and are thus considered to belong to the same species, even though they are geographically separate and physiologically and biochemically very distinct. Using the technique of random amplification of polymorphic DNA to measure the extent of genome polymorphism, the aim of this research was to estimate the similarity of the nuclear genomes of the two strains. The analysis shows that the two strains only share approximately 10% of the total number of amplicons. Surprisingly, the data also indicates, indirectly, that the …


The Effect Of Dendritic Cell Mobilization On Cd8+ T Cell Responses To Influenza A Virus, Adil N. Shivji Dec 2012

The Effect Of Dendritic Cell Mobilization On Cd8+ T Cell Responses To Influenza A Virus, Adil N. Shivji

Electronic Thesis and Dissertation Repository

Influenza A viruses (IAV) cause respiratory infections with potentially catastrophic consequences. Neutralizing antibodies towards surface proteins of IAV prevent reinfection. However, mutations in these proteins allow the virus to evade these antibodies. Enhancing cytotoxic T cell-mediated immunity has been proposed as an attractive strategy to combat flu. Recombinant human FMS-like tyrosine kinase 3 ligand (FL) is known to mobilize dendritic cells (DCs) in mice. Given that DCs are the most potent antigen-presenting cells, I hypothesized that their mobilization by FL will improve the CD8+ T cell response to IAV. Quantification of CD8+ T cell responses to IAV epitopes by intracellular …


Characterization Of The Circadian Properties Of Runt-Related Transcription Factor 2 (Runx2) And Its Role In The Suprachiasmatic Nucleus, Meghan E. Reale Dec 2012

Characterization Of The Circadian Properties Of Runt-Related Transcription Factor 2 (Runx2) And Its Role In The Suprachiasmatic Nucleus, Meghan E. Reale

Electronic Thesis and Dissertation Repository

Circadian rhythms orchestrate physiological, behavioral and cognitive processes in order to anticipate and adapt organisms to key environmental cues. These endogenously driven oscillations are generated by a network of interlocked auto-regulatory transcriptional-translational feedback loops driven forward by the Bmal1/Clock heterodimer transcription factor. Given the ubiquitous and dynamic quality of circadian rhythms, the identification of factors involved in the coordination and regulation of the endogenous oscillations is central in broadening our understanding of biological timing systems. In an examination of gene expression in the mammalian central circadian pacemaker, the hypothalamic suprachiasmatic nucleus (SCN), revealed a previously unreported rhythmic expression of runt-related …


Comprehensive Assessment Of Cnv Calling Algorithms: A Family Based Study Involving Monozygotic Twins Discordant For Schizophrenia, Sujit Maiti Dec 2012

Comprehensive Assessment Of Cnv Calling Algorithms: A Family Based Study Involving Monozygotic Twins Discordant For Schizophrenia, Sujit Maiti

Electronic Thesis and Dissertation Repository

Genetic variability is essential to human individuality. Genetic variation includes differences in sequence at the single nucleotide level to structural variations of large segments of DNA called copy number variations (CNVs). CNVs within a genome can be identified using microarray technology; however, the analysis of microarray results resulting in the “calling” of CNVs is not always precise. The research included in this manuscript describes the identification and analysis of CNVs using three commercially-available packages, Affymetrix® Genotyping ConsoleTM, Partek® Genome SuiteTM and PennCNV, that are most commonly used in the analysis of SNP and CNV data. …


Reduced Translocation Of Cadmium From Roots Is Associated With Increased Production Of Phytochelatins And Their Precursors, Mst. Fardausi Akhter, Brian Mcgarvey, Sheila Macfie Dec 2012

Reduced Translocation Of Cadmium From Roots Is Associated With Increased Production Of Phytochelatins And Their Precursors, Mst. Fardausi Akhter, Brian Mcgarvey, Sheila Macfie

Biology Publications

Cadmium (Cd) is a non-essential trace element and its environmental concentrations are approaching toxic levels, especially in some agricultural soils. Understanding how and where Cd is stored in plants is important for ensuring food safety. In this study, we examined two plant species that differ in the distribution of Cd among roots and leaves. Lettuce and barley were grown in nutrient solution under two conditions: chronic (4 weeks) exposure to a low, environmentally relevant concentration (1.0 μM) of Cd and acute (1 h) exposure to a high concentration (5.0 mM) of Cd. Seedlings grown in solution containing 1.0 μM CdCl …


The Cost Of Ethanol Synthesis During Recovery From Exhaustive Exercise In Grass Carp (Ctenopharyngodon Idella), Simon A. Bradford Dec 2012

The Cost Of Ethanol Synthesis During Recovery From Exhaustive Exercise In Grass Carp (Ctenopharyngodon Idella), Simon A. Bradford

Electronic Thesis and Dissertation Repository

Grass carp (Ctenopharyngodon idella) reduce white muscle glycogen (~14 µmol glucosyl units/g wet tissue) in response to exhaustive exercise. This reduction results in a small increase in muscle lactate (~9 µmol/g wet tissue) and a larger increase in muscle ethanol (~30 µmol/g wet tissue). Tissue-specific and whole-body measures of glycogen, ethanol and lactate confirm that ethanol is the major “anaerobic” glycolytic end-product. Additionally, while peak muscle and blood ethanol levels occur immediately post-exercise, the excretion of ethanol to the environment is delayed, occurring over a 30-minute period beginning ~105 minutes following exercise. As the total amount of ethanol …


Cerebellar Degeneration In Harlequin Mice Is Associated With Inflammation Unaltered By Low-Dose Phenobarbital Treatment, Anita Prtenjaca Dec 2012

Cerebellar Degeneration In Harlequin Mice Is Associated With Inflammation Unaltered By Low-Dose Phenobarbital Treatment, Anita Prtenjaca

Electronic Thesis and Dissertation Repository

Canadian population demographics are shifting to an increase in aged individuals and an increase in the prevalence of neurodegenerative diseases. The post-mitotic nature of most neurons highlights the need to understand the etiology and early mechanisms in neurodegenerative diseases and design targeted therapies. Currently, the etiologies of neurodegeneration are poorly understood but oxidative stress, mitochondrial dysfunction and inflammation are early mechanisms in Alzheimer’s disease, Parkinson’s disease and Amyotrophic Lateral Sclerosis. An anti-aging strategy that can be adapted for use in neurodegeneration is hormesis, where repeated low-level exposures to stressors are beneficial to the cell. Hormesis has demonstrated efficacy in inhibiting …


Functional Significance Of Ilk-Elmo2 Interactions In Epidermal Keratinocytes, Ernest Ho Dec 2012

Functional Significance Of Ilk-Elmo2 Interactions In Epidermal Keratinocytes, Ernest Ho

Electronic Thesis and Dissertation Repository

The epidermis consists of a basal layer of undifferentiated keratinocytes and multiple suprabasal layers of differentiated keratinocytes. Undifferentiated keratinocytes are adherent and highly motile, whereas differentiated keratinocytes are comparatively less motile and downregulate cell attachments to the extracellular matrix. Integrin-linked kinase (ILK) is a scaffold protein implicated in the regulation of many cellular functions in keratinocytes, including cell attachment, migration, phagocytosis, and protein trafficking. To determine the mechanisms by which ILK is involved in these processes, I sought to identify other proteins which may interact with ILK in keratinocytes. I identified Engulfment and Cell Motility 2 (ELMO2) to interact with …


Functional Genomic Investigation Of Aromatic Aminotransferases Involved In Ephedrine Alkaloid Biosynthesis In Ephedra Sinica (Stapf), Korey G. Kilpatrick Dec 2012

Functional Genomic Investigation Of Aromatic Aminotransferases Involved In Ephedrine Alkaloid Biosynthesis In Ephedra Sinica (Stapf), Korey G. Kilpatrick

Electronic Thesis and Dissertation Repository

Ephedra sinica (Ephedraceae) is a broom-like shrub cultivated in arid regions of China, Korea and Japan. This medicinal plant accumulates large amounts of the ephedrine alkaloids, including (S)-cathinone, (1R,2S)-norephedrine, (1R,2S)-ephedrine and (1S,2S)-pseudoephedrine in its aerial tissues. These analogues of amphetamine mimic adrenaline and stimulate the sympathetic nervous system. While much is known about their pharmacological properties, the biological mechanisms by which they are synthesized remains largely unknown. A functional genomics platform was established in order to investigate alkaloid biosynthesis. RNA was extracted from Ephedra sinica stems …


Application Of Cytotoxicity Assays For Detection Of Potentially Harmful Bioactive Compounds Produced By Freshwater Bloom-Forming Algae, Jace Thomas Mclaughlin Dec 2012

Application Of Cytotoxicity Assays For Detection Of Potentially Harmful Bioactive Compounds Produced By Freshwater Bloom-Forming Algae, Jace Thomas Mclaughlin

Electronic Thesis and Dissertation Repository

Detection of harmful bioactive compounds produced by bloom-forming pelagic algae is important to assess the potential risks to communities. We applied two cell-based assays, an erythrocyte lysis assay (ELA) that assesses membrane integrity, and a RTgill-W1 cytotoxicity assay (RCA) that detects changes in cell metabolism, to evaluate the cytotoxic effects of: (1) individual toxins and noxious compounds; and (2) complex mixtures of compounds produced by cyanobacteria and chrysophyte isolates. ELA was insensitive to toxins and noxious compounds except at exceptionally high concentrations (EC50≥106 nM). RCA was sensitive to noxious compounds only, at concentrations greater than reported environmental …


Photocalytic Degradation Of Malic Acid Under Thin Coated Tio2, Vanessa Silveira Rodgher Dec 2012

Photocalytic Degradation Of Malic Acid Under Thin Coated Tio2, Vanessa Silveira Rodgher

Electronic Thesis and Dissertation Repository

Opaque fluids have a limited irradiation transmission. Thus, their decontamination employing near UV irradiation poses significant technical challenges. In the present study, a thin UV-transparent/waterproof glue layer coated with a 1.5 wt% of TiO2 and a new PhotoReactor Cell were implemented. TiO2 irradiation in the PhotoReactor Cell was effected on the TiO2 particle side, not directly in contact with the fluid, allowing the postulation of an “h+” site mobility mechanism on photocatalysis.

Photocatalytic degradation experiments with malic and malonic acid in water at 10, 20, 30 and 40 ppm showed the complete degradation of malic …


Reliability And Validity Of Knee Moments: 3d Gait Analysis In Subjects With And Without Knee Osteoarthritis, Sara E. Richardson Dec 2012

Reliability And Validity Of Knee Moments: 3d Gait Analysis In Subjects With And Without Knee Osteoarthritis, Sara E. Richardson

Electronic Thesis and Dissertation Repository

Quantifying the reliability and validity of gait data in patients with knee osteoarthritis is required to more confidently evaluate effects of interventions and identify potential responders. 109 patients after high tibial osteotomy underwent 3-dimensional gait analysis consisting of four walking trials to calculate the external knee moments in three anatomical planes. The first two trials were compared to the second two trials to evaluate within-session test re-test reliability. 61 patients were matched to 61 healthy controls of similar age, sex and body mass index. Intraclass correlation coefficients were very high, ranging from 0.93 for peak knee adduction moment to 0.84 …


Error Correction In Next Generation Dna Sequencing Data, Michael Z. Molnar Dec 2012

Error Correction In Next Generation Dna Sequencing Data, Michael Z. Molnar

Electronic Thesis and Dissertation Repository

Motivation: High throughput Next Generation Sequencing (NGS) technologies can sequence the genome of a species quickly and cheaply. Errors that are introduced by NGS technologies limit the full potential of the applications that rely on their data. Current techniques used to correct these errors are not sufficient, and a more efficient and accurate program is needed to correct errors.

Results: We have designed and implemented RACER (Rapid Accurate Correction of Errors in Reads), an error correction program that targets the Illumina genome sequencer, which is currently the dominant NGS technology. RACER combines advanced data structures with an intricate analysis of …


The Near Wake Of A European Starling, Adam J. Kirchhefer Dec 2012

The Near Wake Of A European Starling, Adam J. Kirchhefer

Electronic Thesis and Dissertation Repository

The wake of a freely flying European starling (Sturnus vulgaris) was measured using high speed, time-resolved, particle image velocimetry, simultaneously with high speed cameras which imaged the bird. These measurements have been used to generate vector maps in the near wake that can be associated with the bird’s location and wing configuration. A kinematic analysis has been performed on select sequences of measurements to characterize the motion of the bird, as well as provide a point of comparison between the bird of the present study and other birds or flapping wings. Time series of measurements have been expressed …


Nucleoredoxin And Wnt Signaling In F9 Cells, Leanne Sandieson Dec 2012

Nucleoredoxin And Wnt Signaling In F9 Cells, Leanne Sandieson

Electronic Thesis and Dissertation Repository

Nucleoredoxin is a redox sensitive protein recently shown to be involved in the Wnt/β-catenin pathway through binding dishevelled. When Wnt is present, dishevelled prevents a destruction complex from degrading β-catenin. This facilitates the translocation of β-catenin into the nucleus where it binds to TCF-LEF to impart changes in gene expression. This study used mouse F9 cells as a model to examine whether or not nucleoredoxin is involved in augmenting the Wnt/β-catenin signaling required for extraembryonic endoderm differentiation. It was found that nucleoredoxin and three dishevelled isoforms were present in F9 cells. Furthermore, nucleoredoxin was found to bind to dishevelled-2, and …


Involvement Of Interleukin-33/St2 In Myocardial Dysfunction In Murine Model Of Sepsis, Yoonmi Choe Dec 2012

Involvement Of Interleukin-33/St2 In Myocardial Dysfunction In Murine Model Of Sepsis, Yoonmi Choe

Electronic Thesis and Dissertation Repository

The disruption of myocardial extracellular matrix (ECM) has been implicated in myocardial dysfunction during sepsis. However, the underlying mechanism(s) are not clear. Interleukin-33 (IL-33) is a cytokine which regulates collagen synthesis in various cardiac pathologies. The purpose of the present study is to test whether IL-33 contributes to sepsis-induced myocardial dysfunction through regulation of matrix metalloproteinase-9 (MMP-9). The in vivo, feces-induced peritonitis (FIP) in mice and in vitro lipopolysaccharide (LPS) treatments to isolated cardiomyocytes were used. In FIP mice, myocardial IL-33 and MMP-9 expression were increased and myocardial contractility was decreased. Myocardial function in FIP mice was improved when treated …


Timp-2 Decreases The Invasive Potential Of Mcf-7 And Mdamb-231 Cells Independent Of Mmp Inhibition, Mario Cepeda Dec 2012

Timp-2 Decreases The Invasive Potential Of Mcf-7 And Mdamb-231 Cells Independent Of Mmp Inhibition, Mario Cepeda

Electronic Thesis and Dissertation Repository

Tissue Inhibitors of Metalloproteinases (TIMPs) are the natural inhibitors of Matrix Metalloproteinases (MMPs), a family of proteins primarily responsible for Extracellular Matrix (ECM) remodeling. TIMP-2 is a special member of the TIMP family as it is both an inhibitor and promoter of MMP activity, and can also bind the cell surface and signal inside the cell to influence cell behavior. In this study, MDAMB-231 and MCF-7 breast cancer cells were treated with physiological concentration of TIMP-2, which decreased the invasive potential of both cell lines. This was independent of MMP inhibition, and instead a decrease in the expression and secretion …


Neuromuscular Function Following Lengthening Contractions, Geoffrey A. Power Dec 2012

Neuromuscular Function Following Lengthening Contractions, Geoffrey A. Power

Electronic Thesis and Dissertation Repository

Unaccustomed lengthening contractions have been shown to impair muscle function - however little is known regarding this impairment on muscle power - specifically, the velocity component of power during voluntary contractions in humans. The four studies presented in my thesis investigated power-loss following lengthening contractions in healthy young and old women and young men.

The purpose of Study 1 was to determine reliability of velocity-dependent power of the dorsiflexors using the isotonic mode of the Biodex Dynamometer. I determined the isotonic mode is reliable and can be used to track changes in velocity and power following fatigue and lengthening contractions. …


The Role Of Drug Transporters In Statin-Induced Myopathy, Michael J. Knauer Dec 2012

The Role Of Drug Transporters In Statin-Induced Myopathy, Michael J. Knauer

Electronic Thesis and Dissertation Repository

Statins are the first line therapy for treatment and prevention of cardiovascular disease. The 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, or statins, reduce plasma cholesterol levels by inhibiting the rate-limiting step in cholesterol biosynthesis. While statins are well tolerated, up to 15% of patients develop myopathy, manifesting as muscle aches and pain and in rare cases, potentially life-threatening statin-induced rhabdomyolysis. Given that approximately 3 to 4 million Canadians are treated with statins, an estimated 500,000 patients experience associated skeletal muscle side effects that may prevent the continued treatment of hypercholesterolemia. Despite the prevalence of this side effect, little is known regarding …


Septohippocampal Gabaergic Neurons Mediate The Altered Behaviors Induced By N-Methyl-D-Aspartate Receptor Antagonists., Jingyi Ma, Siew Kian Tai, L Stan Leung Dec 2012

Septohippocampal Gabaergic Neurons Mediate The Altered Behaviors Induced By N-Methyl-D-Aspartate Receptor Antagonists., Jingyi Ma, Siew Kian Tai, L Stan Leung

Physiology and Pharmacology Publications

We hypothesize that selective lesion of the septohippocampal GABAergic neurons suppresses the altered behaviors induced by an N-methyl-D-aspartate (NMDA) receptor antagonist, ketamine or MK-801. In addition, we hypothesize that septohippocampal GABAergic neurons generate an atropine-resistant theta rhythm that coexists with an atropine-sensitive theta rhythm in the hippocampus. Infusion of orexin-saporin (ore-SAP) into the medial septal area decreased parvalbumin-immunoreactive (GABAergic) neurons by ~80%, without significantly affecting choline-acetyltransferase-immunoreactive (cholinergic) neurons. The theta rhythm during walking, or the immobility-associated theta induced by pilocarpine, was not different between ore-SAP and sham-lesion rats. Walking theta was, however, more disrupted by atropine sulfate in ore-SAP than …


Cloning And Analysis Of Reck During Early Xenopus Laevis Development, Jessica Willson Nov 2012

Cloning And Analysis Of Reck During Early Xenopus Laevis Development, Jessica Willson

Electronic Thesis and Dissertation Repository

Extracellular matrix (ECM) remodeling is crucial for the development and maintenance of multicellular organisms. Degradation of ECM components occurs through the activity of matrix metalloproteinases (MMPs) and their inhibitors. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) gene encodes a membrane-anchored protein and plays an important role in mediating ECM remodeling by inhibiting MMPs. To date, few in vivo studies exist examining RECK during development. The present study focuses on cloning and examining the expression of RECK during early Xenopus laevis development. A mature cDNA clone of the RECK gene was generated. RT-PCR, in situ hybridization, and immunohistochemistry were used to …


Cold Tolerance Of Each Life Stage Of The Sub-Alpine Willow Leaf Beetle, Chrysomela Aeneicollis, Evelyn C. Boychuk Nov 2012

Cold Tolerance Of Each Life Stage Of The Sub-Alpine Willow Leaf Beetle, Chrysomela Aeneicollis, Evelyn C. Boychuk

Electronic Thesis and Dissertation Repository

To understand the potential effects of climate change on the sub-alpine willow leaf beetle, the cold tolerance strategy and mechanisms involved in cold tolerance were investigated for all life stages. Microhabitat choice and microclimate temperatures within each microhabitat were related to median lethal temperature for each life stage. Summer active and quiescent adults are freeze tolerant, eggs and pupae are freeze avoidant and all larval stages are chill susceptible. Quiescent adults accumulated the highest concentration of glycerol (~24 mM) and haemolymph osmolality (875 mOsm). Haemolymph from pupae had angular crystals suggestive of antifreeze agent activity, but this was absent in …


Evaluating The Impact Of Two Different Methods Of Diabetes Self-Management Education On Knowledge, Attitude, And Behaviours Of Patients With Type 2 Diabetes Mellitus, Laura B. Briden Nov 2012

Evaluating The Impact Of Two Different Methods Of Diabetes Self-Management Education On Knowledge, Attitude, And Behaviours Of Patients With Type 2 Diabetes Mellitus, Laura B. Briden

Electronic Thesis and Dissertation Repository

This study compared the effectiveness of diabetes self-management education (DSME) methods by examining changes in knowledge, attitude, and behaviour (KAB) after receiving education. Participants from a convenience sample were randomized into two groups, one receiving education through conversation maps and the other through traditional group education. Participants’ knowledge and attitude changes were measured by using a repeated measures pre-test/post-test design and changes in Hb A1c were observed. Focus groups were conducted after education was received to obtain perceptions and self-reported behaviour changes. Significant knowledge and attitude score changes were observed in the conversation map group after education. When comparing the …


Characterization Of A Tumour Suppressor Function Of Ranbpm, Elnaz Atabakhsh Nov 2012

Characterization Of A Tumour Suppressor Function Of Ranbpm, Elnaz Atabakhsh

Electronic Thesis and Dissertation Repository

Ran-binding protein M (RanBPM) is an evolutionarily conserved nucleocytosolic protein that has been proposed to regulate various cellular processes, including protein stability, gene expression, receptor-mediated signalling pathways, cell adhesion, development, and apoptosis. Despite the multitude of functions attributed to RanBPM however, little is known regarding the precise mechanisms by which RanBPM executes these cellular roles. In this work, we seek to address this matter by describing functions for RanBPM in the regulation of apoptotic and pro-survival signalling pathways, and in cellular transformation.

We first identify RanBPM as a pro-apoptotic protein that regulates the activation of the intrinsic apoptotic signalling pathway …


The Influence Of Habitat Composition And Configuration On The Genetic Structure Of The Pitcher Plant Midge, Katie Millette Nov 2012

The Influence Of Habitat Composition And Configuration On The Genetic Structure Of The Pitcher Plant Midge, Katie Millette

Electronic Thesis and Dissertation Repository

A major question in landscape genetics is how habitat structure influences spatial patterns of genetic differentiation. In this study, I evaluate the relative importance and effects of aspects of habitat composition (habitat amount) and configuration (patch size and isolation) on the spatial genetic structure of the pitcher plant midge, Metriocnemus knabi, whose larvae are found exclusively within the water-filled leaves of pitcher plants (Sarracenia purpurea) in a system that is naturally patchy at multiple spatial scales (i.e., leaf, plant, cluster, bog). I estimated genetic differentiation (FST) among leaves, plants, and clusters using 11 microsatellite …


Characterization Of Cardiomyopathy In A Mouse Model Of Duchenne Muscular Dystrophy (Dmd) Using Echocardiography, Dce-Ct, And Pet-Fdg, Seyed Hamed Moazami Nov 2012

Characterization Of Cardiomyopathy In A Mouse Model Of Duchenne Muscular Dystrophy (Dmd) Using Echocardiography, Dce-Ct, And Pet-Fdg, Seyed Hamed Moazami

Electronic Thesis and Dissertation Repository

Duchenne muscular dystrophy (DMD) is an X-linked recessive neuromuscular disease that is the result of a loss of functional dystrophin, which causes cardiomyocyte fibrosis and death, leading to cardiomyopathy. In this thesis, I have utilized dynamic contrast-enhanced computed tomography (DCE-CT), positron emission tomography-fluorodeoxyglucose (PET-FDG), echocardiography, and traditional histology to longitudinally assess disease progression and degree of cardiomyopathy in a murine model of DMD (mdx:utrn-/-). No significant changes were observed in the blood flow, blood volume, or cardiac volume measured via DCE-CT, nor in standard uptake value (SUV) of glucose as measured by PET-FDG in the left myocardium between and within …


Ion Homeostasis And Variation In Low Temperature Performance In The Fall And Spring Field Crickets (Orthoptera: Gryllidae), Litza E. Coello Alvarado Nov 2012

Ion Homeostasis And Variation In Low Temperature Performance In The Fall And Spring Field Crickets (Orthoptera: Gryllidae), Litza E. Coello Alvarado

Electronic Thesis and Dissertation Repository

Low temperature performance affects the geographical distribution of insects. The lower critical temperature limits of chill-susceptible insects are likely determined by failure of ion and water balance at low temperature. I used phenotypic plasticity in the cold tolerance of Gryllus pennsylvanicus, and the naturally higher cold tolerance of Gryllus veletis to test the hypothesis that variation in low temperature performance is accompanied by variation in ion and water homeostasis at low temperatures. Low temperature acclimation and cold adaptation enhanced performance at low temperatures. Groups with higher cold tolerance had an enhanced ability to prevent or mitigate the migration of hemolymph …


The Regulation Of Prokaryotic Transposable Elements By The Rna Binding Protein Hfq, Brian J. Munshaw Nov 2012

The Regulation Of Prokaryotic Transposable Elements By The Rna Binding Protein Hfq, Brian J. Munshaw

Electronic Thesis and Dissertation Repository

This thesis investigates the role that the RNA binding protein Hfq has in regulating the mobility of IS Elements and the expression of their transposase genes. Hfq is a known regulator of the IS Element IS10 and is a major component of sRNA pathways in E.coli. In this work, I demonstrate that through the use of a bioinformatics approach to identify a list of additional IS Elements from the IS Finder database, one can successfully identify IS Elements containing Hfq binding sites which may implicate Hfq regulation. One of the identified elements, IS1413, was characterized by …


An Investigation Of The Neural Mechanism By Which The Prefrontal Cortex Facilitates Anti-Saccade Task Performance, Michael J. Koval Nov 2012

An Investigation Of The Neural Mechanism By Which The Prefrontal Cortex Facilitates Anti-Saccade Task Performance, Michael J. Koval

Electronic Thesis and Dissertation Repository

Cognitive control enables us to guide our behaviour in an appropriate manner, such as rapid eye movements (saccades) toward a location or object of interest. A well-established test of cognitive control is the anti-saccade task, which instructs subjects to look away from a suddenly-appearing stimulus. The dorsolateral prefrontal cortex (dlPFC) and anterior cingulate cortex (ACC) are part of a cortical saccade control network that influences the superior colliculus (SC), which sends saccade commands to the brainstem saccade generator. To compare and contrast the roles of the dlPFC and ACC in saccade control, the cryoloop method of reversible cryogenic deactivation was …


An Investigation Into The Combined Effects Of Β-Amyloid Toxicity And Cerebral Ischemia On The Pathological Expression Of Gangliosides., Jeffrey D. Hepburn Oct 2012

An Investigation Into The Combined Effects Of Β-Amyloid Toxicity And Cerebral Ischemia On The Pathological Expression Of Gangliosides., Jeffrey D. Hepburn

Electronic Thesis and Dissertation Repository

Identifying mechanisms underlying the synergistic pathological interaction between stroke and Alzheimer’s disease (AD) can effectively guide future therapeutic strategies for these highly co-morbid conditions. Aberrant ganglioside expression marked by the pathological accumulation of ganglioside GM3 is common to stroke and AD, yet it is unclear whether GM3 is synergistically enhanced in a comorbid model, or if GM3 is a viable therapeutic target. Adult male Wistar rats received a unilateral ischemic striatal infarct via endothelin-1 (ET-1) injection alone or in combination with bilateral intracerebroventricular injection of the β-Amyloid 25-35 peptide (Aβ) to induce generalized Aβ toxicity (Aβ/ET-1). Animals were sacrificed after …