Salicylic Acid: A Key Regulator Of Redox Signalling 1 And Plant Immunity, Mohd Saleem, Qazi Fariddudin, Christian Castroverde

Biology Faculty Publications

In plants, the reactive oxygen species (ROS) formed during normal conditions are essential in regulating several processes, like stomatal physiology, pathogen immunity and developmental signaling. However, biotic and abiotic stresses can cause ROS over-accumulation leading to oxidative stress. Therefore, a suitable equilibrium is vital for redox homeostasis in plants, and there have been major advances in this research arena. Salicylic acid (SA) is known as a chief regulator of ROS; however, the underlying mechanisms remain largely unexplored. SA plays an important role in establishing the hypersensitive response (HR) and systemic acquired resistance (SAR). This is underpinned by a robust and …

Black And White Health Disparities: Racial Bias In American Healthcare, Yasmeen Almomani

Bridges: An Undergraduate Journal of Contemporary Connections

This paper explores the historical implications of race in American society that have led to implicit racism in the healthcare system. Racial bias in healthcare against Black people is a factor in the health disparities between Black and white people in America, such as the gap in life expectancy, infant death, and maternal mortality. Black people are more likely to report racial discrimination from healthcare providers, which is a reason for the decreased quality of care received. The past justifications of slavery, the Tuskegee syphilis study, and the medical experimentations on Black women are horrifying but were considered acceptable in …

Temperature Regulation Of Plant Hormone Signaling During Stress And Development, Christian Castroverde, Damaris Dina

Biology Faculty Publications

Global climate change has broad-ranging impacts on the natural environment and human civilization. Increasing average temperatures along with more frequent heat waves collectively have negative effects on cultivated crops in agricultural sectors and wild species in natural ecosystems. These aberrantly hot temperatures, together with cold stress, represent major abiotic stresses to plants. Molecular and physiological responses to high and low temperatures are intricately linked to the regulation of important plant hormones. In this review, we shall highlight our current understanding of how changing temperatures regulate plant hormone pathways during immunity, stress responses and development. This article will present an overview …

Cross-Sectional Nutrition Profile Of Palliative Home Care Clients In Ontario And Performance Of The Interrai Palliative Care Nutrition Clinical Assessment Protocol, Tara Stevens, Heather Keller, Nicole Williams, James Downar, Dawn M. Guthrie

Health Sciences Faculty Publications

Background: The nutrition profile of palliative home care clients is unknown. This study describes this group and their nutrition issues and evaluates the performance of the interRAI nutrition Clinical Assessment Protocol (CAP).

Methods: This was a cross-sectional secondary analysis using Ontario interRAI Palliative Care (interRAI PC) Assessment data. The sample represents 74,963 unique Ontario home care clients assessed between 2011 and 2018. Frequencies and standardized differences (stdiffs) of nutrition characteristics were presented for cancer (n = 62,394) and noncancer (n = 12,569) diagnostic subgroups. Rates of triggering the nutrition CAP were presented by nutrition issue to evaluate its performance.

Results: …

The Impact Of Combined Flexion And Compression On The Mechanical Integrity Of The Annulus Fibrosus, Keaton Briar

Theses and Dissertations (Comprehensive)

Introduction: Intervertebral disc (IVD) herniation is characterized by an expulsion of nucleus pulposus (NP) material through the annulus fibrosus (AF). The AF contains two major adhesive structures, the intralamellar matrix and the interlamellar matrix, which act to maintain the strength of the AF and prevent NP material migration. As a herniation occurs, clefts form within the intralamellar matrix, pushing the NP between adjacent collagen fibres; meanwhile, delamination of the interlamellar matrix causes the NP to pool between layers of the AF. Further, herniation more readily occurs in a combined loading scenario of both compression and flexion. Flexion, and in particular …

Exploring The Relationship Between Dog Ownership, Physical Activity, And Mental Health, Stephanie Ho, Jennifer Robertson-Wilson, Mark Eys

Theses and Dissertations (Comprehensive)

The physical and mental health benefits of regular physical activity have been well-documented (e.g., Reiner et al., 2013; White et al., 2017). Additionally, owning a dog is associated with positive health outcomes as owners are encouraged to walk. Dogs are also a source of comfort during stressful times for those in their presence (e.g., Brown & Rhodes, 2006; Westgarth et al., 2017). The aim of this study was to examine the relationship between dog ownership, physical activity, and mental health among the university student population. Over 500 university students completed questionnaires assessing their demographic information, mental health, dog ownership status, …

Breaking The Chain – The Role Of Intersexual Genetic Correlations In Sexual Dimorphism And The Consequences And Limits Of Their Evolution, Matthew Ma Maoloni, Tara Newman, Tristan Af Long Dr.

Theses and Dissertations (Comprehensive)

In many sexually reproducing species, males and females often differ in countless ways beyond their primary sexual organs. This phenomenon is known as sexual dimorphism, and it is generally considered to be an adaptive response to differences in the selection pressures experienced by males and females. Despite the advantages associated with sexual dimorphism, it does not evolve completely unhindered – there are plenty of biological effects that can limit the extent and rate of divergence between the sexes. This research project focusses on the potential role of the intersexual genetic correlation (r_mf­) – which describes the …

Composition And Homology In The Taxonomic Classification Of Escherichia Coli, Tanya Irani

Theses and Dissertations (Comprehensive)

As new techniques have been introduced, specifically the possibility of complete genome sequencing, better methods of defining bacterial species have also been proposed. One of the most recently proposed methods, using bioinformatic techniques, is to calculate the average nucleotide identity (ANI) between the homologous genome segments of different isolates. Another method for species discrimination that has been tested successfully is the similarity of DNA compositional signatures. However, in a recent update, DNA signatures split the available Escherichia coli complete genomes into three groups. To check if this result was consistent with such genomes belonging to different species, we tested methods …

On The Structure And Function Of Mitochondrial Uncoupling Proteins: The Case Of Ucp2, Afshan Ardalan

Theses and Dissertations (Comprehensive)

Uncoupling proteins (UCPs) are regulated proton transporters of the mitochondrial inner membrane. UCP-mediated proton leak negatively impacts the rate of ATP synthesis. Despite the importance of their physiological role(s) in certain tissues, molecular aspects of UCPs’ structure-function relationships are not fully understood. The current study explores the tertiary and quaternary structure of UCP2, as well as its proton transport mechanism in lipid membranes. The proteins were expressed in the E. coli inner membrane, purified and reconstituted into liposomes. Proteins were characterized by semi-native SDS-PAGE. Circular dichroism spectroscopy (CD) and fluorescence quenching assays were utilized to study the conformation of proteins …

Physiological Impacts Of Lampricides On Invasive Sea Lamprey (Petromyzon Marinus) And Non-Target Fishes, Razvan, Adrian Ionescu

Theses and Dissertations (Comprehensive)

Parasitic sea lamprey (Petromyzon marinus) ingest large quantities of blood from fishes using their oral disc and rasping tongue, most often killing the host. In the early 1900s, sea lamprey invaded the Laurentian Great Lakes, decimating sport, commercial and culturally significant fisheries. Since the early 1960s, chemical control using the lampricides 3- trifluoromethyl-4-nitrophenol (TFM) and niclosamide have helped to reduce sea lamprey populations by 90%. Lampricides are applied to larval lamprey nursery streams targeting many generations of lamprey at once. However, there is concern about the potential adverse effects of lampricides on other fishes, particularly vulnerable lake sturgeon (Acipenser fulvescens) …

Dsrna Conjugated Phytoglycogen Nanoparticles As An Innate Immune Stimulant To Prevent Viral Infections In Rainbow Trout And Atlantic Salmon, Kayla Samms

Theses and Dissertations (Comprehensive)

Salmonids are one of the world’s most farmed fish species. These aquatic vertebrate species rely heavily on their innate immune responses to defend themselves against invading pathogens. Although commercial vaccines are available against some viral and bacterial pathogens affecting salmonids, their protective efficacy is variable. Using a prophylactic inducer of local and systemic innate immune responses could have significant implications in salmonid aquaculture. A potent inducer of the innate immune response in fish is double-stranded RNA (dsRNA), a molecule that all viruses make during their replicative cycle. Polyinosinic:polycytidylic acid (polyI:C) is a synthetic dsRNA commonly used to induce type I …

A Bioinformatic Analysis Of The Biosynthesis Of Carotenoids In The Copepod Tigriopus Californicus, Anchalya Balasubramaniam

Theses and Dissertations (Comprehensive)

Abstract

Biological pigments, also called biochromes, are coloured compounds which are displayed by a variety of life forms, including animals, due to selective colour absorption. The combination of light absorption and reflection enables each pigment to portray a distinct colour which results in the broad spectrum of colours we observe in our surroundings. Carotenoids are a large group of yellow, orange, and red biological pigments found in living organisms. Our current biomolecular knowledge of carotenoids is heavily derived from studying the pathway in photosynthetic prokaryotes, bacteria, fungi, and plants. Carotenoid pigments are exceptionally multifunctional as they act as photo-protectors against …

Wildlife Forage Recovery Following Boreal Wildfire, Alexis Jorgensen, Jennifer Baltzer

Theses and Dissertations (Comprehensive)

Climate change is altering the boreal wildfire regime through increases in the extent and severity of burning and reductions in fire return intervals. These changes can alter the regeneration trajectory of canopy species and ground vegetation, with implications for wildlife habitat. There is some uncertainty about the timelines of when different animal species will use burned areas as their preferred forage taxa recover following fire, and how such recovery is mediated by environmental factors. Here, we aim to address these knowledge gaps through the following questions: 1) What are the main forage types consumed by boreal wildlife and how much …

Drivers And Consequences Of Alnus Alnobetula (Green Alder) Distribution At The Taiga-Tundra Ecotone Of The Northwest Territories, Cory Wallace

Theses and Dissertations (Comprehensive)

Climate warming in the Arctic is occurring considerably faster than the global average. One of the most widespread biological responses to this warming in terrestrial systems has been a marked increase in the productivity of shrubby vegetation. Increased shrub growth and reproduction has the potential to alter both local and global aspects of ecosystem function, making understanding its drivers and environmental impact an important research priority. In this context, considerable research has focused on characterizing relationships between shrub cover, abiotic conditions, and understory communities. However, fewer studies have co-located measurements of these components simultaneously in undisturbed tundra shrub patches to …

Investigating The Antitumor Effects Of A Dsrna-Nanoparticle Complex In An In Vitro Ovarian Cancer Model, Aaron Lewis

Theses and Dissertations (Comprehensive)

An estimated 1 in 70 women will be diagnosed with ovarian cancer in their lifetime. Despite advanced detection and treatment methods, it remains a silent killer with an expected survival rate of 50%. A developing method in cancer treatment is the use of compounds that stimulate the immune system to aid in the body's fight against the disease. This project focused on the use of the potent immune stimulant double-stranded RNA (dsRNA), commercially available as polyinosinic:polycytidylic acid, poly(I:C), to induce cytotoxicity in two ovarian cancer cell lines; SKOV-3 and OVCAR-3. Some challenges exist with the delivery of dsRNA due to …