Life Sciences Commons^™

Tracing Nutrient Sources To Lipid Production In Insects Using Stable Isotope (Δ13c, Δ2h) Tracers: Implications For Nutritional Physiology Of Migratory Species., Libesha Anparasan, Keith A. Hobson

Western Research Forum

Using stable isotope measurements of insect tissues to determine origin and migratory patterns is well established. However, isotopically determining nutritional origins of lipids, the primary fuel of migration, has not been as thoroughly researched. We explored isotopic links between diet and stored lipids in laboratory raised True armyworm moths (Mythimna unipuncta) using δ¹³C and δ²H measurements. Pupae were randomly separated into four groups (n=20) and fed isotopically distinct nectar, each consisting of a combination of high δ¹³C (C4 sugar), or low δ¹³C (C3 sugar) carbohydrate, with high δ²H (deuterium spiked), …

Regulation Of Endoplasmic Reticulum Stress Sensitivity By Torc1 Signalling In Yeast, Khadija Ahmed, Patrick Lajoie

Western Research Forum

Incorrect folding of secretory proteins in the endoplasmic reticulum (ER) results in an aberrant accumulation of misfolded proteins (ER stress) and activates a coping mechanism known as the unfolded protein response (UPR). While the mechanisms of UPR activation have been well established, how it integrates with other stress responses remains unclear.

Given that TORC1 is an important regulator of cell growth during protein misfolding stress, we sought to investigate how TORC1 signalling acts in parallel with the UPR to regulate ER stress sensitivity. Our studies employ the budding yeast, Saccharomyces cerevisiae, a biochemically traceable model organism that allows for …

Uncovering The Role Of Ovol1 In Placental Stem Cell Differentiation Using Saccharomyces Cerevisiae, Maram Albakri, Patrick Lajoie, Stephen Renaud, Gargi Jaju, Hazel Dhaliwal

Western Research Forum

OVOL1 is a conserved transcription factor involved in regulating cytrophoblast differentiation in the placenta. Our objective for this study is to use Saccharomyces cerevisiae to uncover the role of OVOL1 in placental stem cell differentiation and proliferation. Previous research suggests that OVOL1 regulates cytotrophoblast progenitor state by regulating genome acetylation. Therefore, our study aims to determine how OVOL1 effect yeast growth and the yeast acetylome, and to use the yeast model to determine downstream targets of OVOL1. In order to understand the role of OVOL1, we will develop a yeast model and employ growth assays to assess growth defects and …

Role Of Gp120 Glycosylation In Sexual Transmission Of Hiv, Yingxue Sun, Adam Meadows, Najwa Zebian, Eric Arts, Carole Creuzenet

Western Research Forum

Background:

In chronic HIV patients, the viral populations are genetically diverse due to mutations introduced by the viral reverse transcriptase during HIV replication. However, more than 80% new infections result from single transmission founder (TF) viruses; therefore, targeting the TFs is key to control AIDS worldwide.

Gp120 is a glycosylated envelope protein required for HIV infection, propagation, and transmission. Glycans on gp120 influence HIV infectivity through their interactions with lectins, the carbohydrate-binding immune proteins in the host mucosa. To transmit sexually, viruses must overcome the lectin traps to access more target T cells.

Hypothesis:

TF viruses are less likely to …

Knocking Out A Negative Regulator Of Hedgehog Signaling Blocks Differentiation Of Cells Into Neurons, Danielle Margaret Spice, Gregory M. Kelly Ph.D.

Western Research Forum

Hedgehog (Hh) signaling, one of many different protein signaling pathways found in mammals, is vital in many stage of neural development. A major negative regulator of Hh signaling is a protein known as Suppressor of Fused (SUFU), which acts to sequester the full length Gli transcription factors, proteins that can turn genes on and off, in the cytoplasm or facilitates its conversion to a repressive form. The P19 embryonal carcinoma cell line is a model of hind-brain neuronal differentiation and the involvement of Hh signaling, in particular the role of SUFU in this process has yet to be explored. We …

The Dissociable Impact Of Auditory Vs. Visual Emotional Cues On Visual Processing, Emma K. Stewart Bsc, Derek Gv Mitchell Phd

Western Research Forum

Background: Emotional information has privileged access to processing resources, which can cause it to have a distracting or facilitating effect on task performance for reasons that are poorly understood. The sensory modality through which it is presented may be one determining factor. Some findings suggest that auditory stimuli facilitate visual task performance while visual stimuli interfere with it, but there are conflicting findings.

Hypothesis: We hypothesize that emotional content of a different sensory modality from the task improves task-related performance via a general alerting and arousing effect for all stimuli, while emotional content of the same modality disrupts performance when …

An Application Of The Modifiable Areal Unit Problem: Optimizing Cluster Method Parameters To Produce Predictive Data For Hiv Outbreaks, Connor J. Chato, Art Fy Poon

Western Research Forum

Background

A popular approach to study HIV outbreaks is to cluster cases based on genetic similarity. However, there is no widely-used statistical criterion which optimizes the parameters for sequence-based clustering methods. The relationship between a cluster-defining similarity threshold and it’s associated set of clusters can be analogized to the aggregation level in the Modifiable Areal Unit Problem (MAUP).

Hypothesis

Based on the selection of aggregation level for study partitions in MAUP, we present a statistical framework to optimize the similarity threshold for pairwise distance algorithm TN93 (http://github.com/veg/tn93). We hypothesize that defining this threshold includes case connections such that …

The Wet Bridge Transfer System: An Novel In Vitro Tool For Assessing Exogenous Surfactant As A Pulmonary Drug Delivery Vehicle, Brandon J. Baer

Western Research Forum

Background:

Due to its complex branching structure, direct drug delivery to the remote areas of the lung is a major challenge. Consequently, most therapies, such as those treating pulmonary infection and inflammation, must utilize large systemic dosing, with the potential for adverse side effects. A novel alternative strategy is to use exogenous surfactant, a material capable of distributing throughout the lung, as a pulmonary drug delivery vehicle.

Objective:

Utilize an in vitro transferring system to assess exogenous surfactant (BLES) as a pulmonary delivery vehicle for different therapeutics.

Methods:

An in vitro technique was developed to simultaneously study surfactant delivery and …

Dairy Intake And Cognitive Function In Canadian Older Adults, Mariam R. Ismail Miss, Alan Salmoni

Western Research Forum

Background: Dietary intake is one of the modifiable factors that may affect older adults’ cognitive function in their later years. Few research has considered the potential role of dairy foods on cognitive function. Methods: Across-sectional study was undertaken in 2014. Cognitive function was assessed using The Montreal Cognitive Assessment (MoCA), Rey Complex Figure Test and Recognition Trial (RCFT), Trail-Making Test (TMT), Victoria Stroop Test (VST) and the Digit Span Test (DST). Dietary intake was assessed via estimated 5-day food intake records and analyzed for saturated fat, vitamin D and calcium. Results: A total of 32 participants (8 males and 24 …

Optimization Of The Touchscreen-Based Visuomotor Conditional Learning Task In Mice, Oren Princz-Lebel, David I. Wasserman, Miguel Skirzewski, Penny A. Macdonald, Lisa M. Saksida, Tim J. Bussey

Western Research Forum

The translational gap between animal models and clinical trials is a longstanding, yet largely unresolved, limitation in the study of cognition. This discrepancy is largely due to the differences in how cognition is assessed in animal models compared to those in clinical populations. In the stimulus-response (S-R) learning literature, for example, the techniques used to assess the acquisition of habitual behaviour differ greatly across species, leading to poor cross-species translation and often conflicting results. As a result, we set out to optimize a S-R learning task in mice using the touchscreen-based operant technologies. Similar to human studies, this touchscreen technique …

Genomic Analysis Of Mitochondria Of Metschnikowia, Dong Kyung Lee

Western Research Forum

Genomic Analysis of Mitochondria of Metschnikowia

Background

Our current understanding of mitochondrial genomes is biased toward metazoans, which represent the majority of sequenced mitochondrial DNAs (mtDNAs). The high diversity in size, shape, and gene synteny among yeast mitochondrial genomes make them an appealing alternative to those of metazoans for studying genomic diversity and evolution. Recently, more than 60 draft-genome assemblies of large-spored Metschnikowia species have been determined. Complete mitochondrial genomes of these yeasts, however, are yet to be constructed and characterized. Therefore, I propose to construct and analyze the mitochondrial genomes of all 61 strains of large-spored Metschnikowia species.

Hypothesis …

Cell-Free Dna Release During Programmed Cell Death In Ischemia Reperfusion Injury, Alexander Dionne, Anthony M. Jevnikar, Zhu-Xu Zhang

Western Research Forum

Transplantation is invariably associated with acute allograft injury caused by ischemia reperfusion injury (IRI). This injury causes cells of the allograft to undergo various forms of programmed cell death including apoptosis and necroptosis. During programmed cell death, immunogenic molecules are released from cells, one of which is cell-free DNA (cfDNA). We hypothesize that cfDNA is released by microvascular endothelial cells (MVECs) during programmed cell death of IRI and that cfDNA acts as both a biomarker for cellular injury as well as a biologically active molecule capable of amplifying inflammation and organ injury.

Our results indicate that cfDNA is released by …

Optimization Of Simultaneous Facial Emg And Fmri, Maggie Prenger

Western Research Forum

The scientific study of emotion began in the 19^th century with Duchenne’s study of the “universal and immutable” language of facial expressions. In The Mechanism of Human Physiognomy, he manipulates human facial expressions by electrically stimulating facial muscles. Facial electromyography (EMG) is a modern technique that is reminiscent of Duchenne’s work; it allows researchers to measure facial muscle activity through surface recording electrodes, providing a real-time measure of natural emotional reactions.

Although facial EMG is a reliable measure of emotional behavior, it fails to provide any information about brain activity responsible for emotional processes. Functional magnetic resonance imaging (fMRI) …

Spontaneous Mimicry Of Emotional Facial Expressions As A Function Of Trait Sadism, Cathleen Fleury, Mary Ritchie, Derek Mitchell

Western Research Forum

Using electromyography (EMG), it has been shown that facial muscles imperceptibly mirror the facial expressions of others, a phenomenon referred to as spontaneous facial mimicry. Facial mimicry may be involved in empathy processing, and is impaired in several empathy deficit disorders. It was previously believed to follow the direct-matching principle, a theory postulating that spontaneous facial mimicry involves the observer mirroring their partner’s expression exactly. However, several recent studies have demonstrated that context and individual differences may be influencing factors of spontaneous facial mimicry. In the present study, we propose to investigate the relationship between facial mimicry and empathy through …

Obstacle Negotiation And Dual-Tasking In People With A Unilateral Transtibial Amputation., Humberto Omana, Michael Payne, Ricardo Viana, Susan Winnifred Hunter

Western Research Forum

Background: Falls in people with a lower limb amputation (PLLAs) are common and most often occur while walking, resulting in physical and psychological consequences that adversely affect quality of life. Walking is a complex motor task requiring cognitive resources. Due to walking with a prosthesis, PLLAs report focussing on every step they take, indicating greater cognitive needs. However, cognitive resources are limited, and most of our everyday activities also involve the simultaneous performance of motor and cognitive tasks, known as dual-tasking. The inter-relationship between mobility, cognition and postural stability in PLLAs using a prosthesis is just starting to be understood. …

Effect Of Stress And Methylmercury Exposure On Song Sparrows (Melospiza Melodia) Energy Balance., Claire Bottini

Western Research Forum

Mercury is an endocrine disruptor well known for its deleterious impacts on wildlife and humans but its effects on songbirds’ populations still require more investigation. In their natural habitat, birds face multiple stressors (e.g. predation, food unpredictability, inclement weather) in addition to pollutants. However the accumulated effects of both stress and pollutants are rarely studied. Such co-occurring pressures may synergistically increase risk for birds as both stress and mercury exposure may disrupt energy acquisition and/or allocation. My project aims to determine the interactive effects of stress and mercury exposure on songbird energy balance. Adults’ song sparrows (Melospiza melodia) …

Modelling Non-Linear Functional Responses In Competitive Biological Systems., Nickolas Goncharenko

Western Research Forum

One of the most versatile and well understood models in mathematical biology is the Competitive Lotka Volterra (CLV) model, which describes the behaviour of any number of exclusively competitive species (that is each species competes directly with every other species). Despite it's success in describing many phenomenon in biology, chemistry and physics the CLV model cannot describe any non-linear environmental effects (including resource limitation and immune response of a host due to infection). The reason for this is the theory monotone dynamical systems, which was codeveloped with the CLV model, does not apply when this non-linear effect is introduced. For …

Role Of Pu.1 And C/Ebpα In Remodelling The Interleukin (Il)-1Β Enhancer-Promoter Interaction, Woohyun Cho, Soon-Duck Ha, Sung Ouk Kim

Western Research Forum

Background: IL-1b is a potent inflammatory cytokine promptly expressed in activated myeloid immune cells. Among various transcription factors, PU.1 and CCAAT/enhancer-binding protein alpha (C/EBPa) play a key role in the lineage commitment of myeloid cells. To date, however, the exact mechanisms by which these lineage-determining transcription factors employ to regulate the expression of myeloid-specific genes remains elusive; thus, this study explores the role of PU.1 and C/EBPa in remodelling the chromatin conformation that allows ample production of IL-1b.

Methods: To examine the mechanism of these lineage-determining transcription factors, production of IL-1b and enhancer-promoter interactions were analyzed in non-myeloid B16-BL6 cells …

Using Computer Algorithms To Elucidate Zebra Finch Reproductive Behaviour, Tanya T. Shoot, Sophie C. Edwards, Robert J. Martin, Susan D. Healy, David F. Sherry, Mark J. Daley

Western Research Forum

Birds that experience variation in climatic conditions must maintain a stable nest temperature during incubation for successful hatching of offspring. Varying nest structure and incubation behaviour may be the methods birds use to regulate nest temperature. We used a modeling approach to investigate how birds adjust incubation behaviour to ambient temperature.

Hidden Markov Models (HMM) have been used previously to predict the spatial distribution of animals based on the models’ ability to classify movement behaviour. We used a HMM to predict zebra finch (Taeniopygia guttata) incubation behaviour and nest structure from a nest temperature data set. The full …

Developing Novel Therapeutics For Bacterial Lung Infections, Brandon J. Baer, Ruud Veldhuizen, Cory Yamashita

Western Research Forum

Background: Bacterial lung infections are leading causes of death worldwide. Unfortunately, increasing resistance to antibiotics and the inflammation often accompanying these infections are leading to poor outcomes despite antibiotic intervention. Complicating treatment further, the tree-like branching structure of the lung makes drug delivery to distal sites of infection difficult. Our research aims to address these challenges by developing new therapeutics and new tools to improve and assess drug delivery, bacterial killing and inflammation. Our therapy combines host defense peptides, which have been shown to kill antibiotic-resistant bacteria and down regulate inflammation, with a pulmonary vehicle, exogenous surfactant, that can improve …

Multisensory Integration And Autistic Traits Using Non-Sociolinguistic Information, Sébastien A. Lauzon, Samantha E. Schulz, Zack I. Cohen, Ryan A. Stevenson

Western Research Forum

Background: Sensory processing issues are one of the most common complaints in autism spectrum disorder (ASD). One area of sensory difficulties in ASD that has been the focus of intense research in recent years is multisensory integration (MSI), or the ability to bind auditory and visual information into a single, unified percept. While integration of social or linguistic information is consistently shown to be an area of difficulty in ASD, results are less clear with simple, non-sociolinguistic stimuli. This study aims to address this ambiguity by determining whether MSI of non-sociolinguistic sensory information is related to traits and symptomatology …

Maternal Protein Restriction (Mpr): A Risk Factor For Acute Respiratory Distress Syndrome (Ards), Reza Khazaee

Western Research Forum

Background: Acute respiratory distress syndrome (ARDS) is defined as severe lung dysfunction. The lung impairments in ARDS result from alterations to pulmonary surfactant; a lipid-protein mixture coating the inside of the lung and maintains the lungs’ ability to expand easily. Due to a lack of effective pharmacological therapies mortality associated with ARDS is over 30%. Our research focuses on risk factors that indicate a susceptibility to the disease, which could provide new and early therapeutic options. One such potential risk factor is Maternal Protein Restriction (MPR). MPR is defined by low birth weight and contributes to a variety of adult-onset …

Tinnitus And Dysfunctional Interactions Between Distributed Resting State Networks, Sivayini Kandeepan

Western Research Forum

It is known that peripheral lesions in the cochlea or the auditory nerve produce dysfunctional input to central auditory structures and induce changes in the auditory system causing tinnitus. Recently, it has been proposed that the unified percept of tinnitus could be considered as an emergent property of multiple overlapping dynamic brain networks, each encoding a specific tinnitus characteristic.

The aim of our study was to investigate the neuronal activation patterns associated with specific clinical tinnitus characteristics using fMRI. We hypothesize that tinnitus clinical characteristics could be associated with specific resting-state activity and connectivity patterns and that this could be …

A Chimeric Nucleobase - Phenylazo Derivative As An Intrinsic Nucleobase Quencher, Gyeongsu Park, Timothy Martin-Chan, Amer El Samm, Robert H.E. Hudson

Western Research Forum

Molecular beacons are important bioanalytical probes which are most often

constructed from a single-stranded oligonucleotide which has been labeled at

opposite termini with a fluorophore and a quencher. When the fluorophore and

quencher are in close proximity, no fluorescence is observed due to FRET

(Fluorescence Resonance Energy Transfer). DABCYL (4-dimethylaminoazobenzene-

4'-carboxylic acid) has been used as a quencher in the molecular beacon to absorbs

excitation energy from a fluorophore and to dissipate the energy as heat. However,

DABCYL is unable to form a base-pair and is conventionally placed as an overhanging

residue. This produces a derivative wherein the chromophore has …

P31. Assessing The Long Term Effects Of Perceived Predation Risk On The Avian Brain, Lauren E. Witterick

Western Research Forum

Predators affect prey populations not only through direct killing, but also through the perception of predation risk. Responding to predator threats is critical for prey survival, however perceived predation risk can have lasting effects ranging from individual changes in neurobiology up to the population level. My research focuses on the lasting effects of predator ‘fear’ on the avian brain. I will be using auditory playbacks to manipulate predation risk in black-capped chickadees (Poecile atricapillus) in acoustic isolation and brown-headed cowbirds (Molothrus ater) in large outdoor aviaries. Lasting behavioural changes have been found in black-capped chickadees one week after …

P08. Unravelling Organelle Genome Evolution Architecture Using Rna-Sequencing Data, Matheus Sanita Lima, David Roy Smith

Western Research Forum

Background: Mitochondria genomes vary from 11 Mb to 6 kb, while plastids can vary from 1 Mb to 30 kb. Non-coding DNA accounts for most of this size variation, but the mechanistic and evolutionary reasons for that are still unknown. Next generation sequencing has generated unprecedented amounts of genomic and transcriptomic data that can be used for organelle genome evolution studies. However, most of these data is used only for the study of cell nucleus. Therefore, I decided to use these untapped data source to investigate the transcription of organelle genomes in plastid-bearing protists.

Methods: I mapped the transcriptomes over …

P17. P3b Event-Related Potentials Show Changes In Varsity Football Players Due To Accumulated Sub-Concussive Head Impacts, Jeffrey S. Brooks, James W. Thompson, James P. Dickey

Western Research Forum

BACKGROUND: Concussion has been a focus in football at all levels of participation. However, there is a growing appreciation that repetitive sub-concussive impacts may have more significant effects on overall neurological health than the isolated diagnosed concussions that have been the focus of recent research. The purpose of this study was to evaluate the relationship between the number of head impacts that players experience throughout the season and their P300 evoked potential.

METHODS: Canadian university football players (n=45) were separated into three groups based on player mass and position/skill (small-skilled, big-skilled and big-unskilled). Groups were separated into low and high …

P24. The Birds And The Beats: Perception Of A Beat In An Avian Model, Brendon Samuels

Western Research Forum

Background: Beat perception is a complex cognitive skill that enables humans to “feel” the beat in music, and is an essential component of synchronization of behavior and dance. The mechanisms in the human brain that facilitate beat perception are not entirely understood, and have only been studied thus far using non-invasive techniques. Some animals, such as songbirds, also seem to be able to detect a beat in rhythms, though this has never been formally tested independent of motor synchronization.

Methods: An operant experiment is used to assess if European starlings, a type of songbird, are capable of categorizing …

P32. Altered Sensory Processing In Response To Novel Dreadd-Induced Inactivation Of Gaba In Pedunculopontine Tegmental Nucleus, Niveen Fulcher

Western Research Forum

Niveen Fulcher¹, Cleusa De Oliveira², & Susanne Schmid^1,2

¹Schulich School of Medicine & Dentistry, University of Western Ontario

²Anatomy and Cell Biology, University of Western Ontario

Altered sensory processing in response to novel DREADD-induced inactivation of GABA in pedunculopontine tegmental nucleus

Background: Sensory processing deficits are associated with certain psychiatric illnesses, such as schizophrenia and autism spectrum disorder (ASD). Sensory filtering and sensorimotor gating are evolutionarily conserved preattentive responses that filter and block redundant sensory stimuli that would otherwise overwhelm our brains. To date, underlying mechanisms of these deficits are undefined. Prepulse …

P02. Production Of A Protein Subunit Vaccine For Mannheimia Haemolytica In Lettuce Chloroplasts, Coby K. Martin

Western Research Forum

The cattle industry worldwide is ravaged by bovine respiratory disease (BRD), a bacterial disease caused by Mannheimia haemolytica. We have designed a chimeric protein subunit vaccine against M. haemolytica based on recent evidence demonstrating the protective potential of antigens against a virulence factor, leukotoxin, in addition to a surface lipoprotein. Plant-based production of this protein vaccine provides a safe and inexpensive alternative to traditional production methods. Plant-base production also supports the use of an edible vaccine that will deliver antigens to pharyngeal tissues to provide local immunization against M. haemolytica to prior to its progression into the lungs. Chloroplasts …