Life Sciences Commons^™

Assessing The Upper Critical Limit Of The Thermoneutral Zone In Laboratory Mice, Teumbo Ngunte

Electronic Theses and Dissertations

Endothermic organisms such as mammals and birds rely on high energy budgets to regulate body temperature. Many studies have previously investigated the thermo-regulation of mammals under the lower critical temperature of the thermoneutral zone, yet our knowledge in determining the upper critical limits is still scarce. As an endotherm, lab mice (Mus musculus) are perfect models to determine the cost to maintain constant body temperature as ambient temperature increases. The upper critical temperature of the thermoneutral zone of this species has been estimated to be above 32°C and below 34°C. By utilizing different genetic backgrounds of lab mice in this …

Providing Experimental Evidence For Mouse Telomerase Reverse Transcriptase As A Novel And Unique Adult Neural Stem Cell Marker, Caroline Dean Curtis

Electronic Theses and Dissertations

With the prevalence of neurodegenerative pathologies in our society today it is imperative that we begin to look at novel approaches to the underlying problem of dying neurons that are not replaced. Adult neural stem cells exist naturally and could potentially be manipulated into targeted repair of damaged brains, given substantial research. The first step in this process is to find a way to specifically mark the earliest subset of these cells, the quiescent adult neural stem cells. Here we provide evidence for the existence of a novel and unique qANSC marker in mouse telomerase reverse transcriptase (mTERT). mTERT has …

Characterization And Functional Rescue Of Congenital Muscular Dystrophy With Megaconial Myopathy In A Mouse Model Of The Disease, Ambreen A. Sayed

Electronic Theses and Dissertations

Congenital muscular dystrophy with megaconial myopathy (MDCMC) is an autosomal recessive disorder characterized by progressive muscle weakness and wasting. Megamitochondria in skeletal muscle biopsies and cognitive impairments in MDCMC patients are observations exclusive to this type of muscular dystrophy. The disease is caused by loss of function mutations in the choline kinase beta (CHKB) gene which results in dysfunction of the Kennedy pathway for the synthesis of phosphatidylcholine (PC). A rostro-caudal muscular dystrophy (rmd) mouse with a deletion in the Chkb gene resulting in MDCMC-like symptoms has been reported by our lab. In order to test if the rmd mice …

Modeling Human Cancer Therapy Response In Patient Derived Xenografts, Joan Malcolm

Electronic Theses and Dissertations

Patient‐derived xenografts (PDXs) generated by implanting human tumor tissue into a transplant compliant mouse host have been of increasingly importance to preclinical development and have been demonstrated to have advantages compared to cancer cell lines and cell‐line xenografts (CLX) for modeling therapeutic responses in cancer. Nevertheless, many open questions remain regarding the relationship between study design factors and classification of treatment response and the molecular fidelity of tumors passaged in PDXs relative to the original patient tumor(s). The research described in this dissertation addresses both of these significant issues related to the use of PDXs as a tool for modeling …

Microplastics In Full View: Birds As Bioindicators Of Malta's Coastal Ecosystem Health, Dalton Brauer

Masters Theses, 2010-2019

Plastic pollution has recently become a widely studied topic, yet research on microplastics has remained lacking for specific geographic regions. Microplastics are small plastics resulting from degradation or the dumping of raw material and can lead to deleterious impacts on the coastal marine environment and its organisms. To assess Malta’s coastal environmental health, water birds (inshore, offshore and pelagic species) were used as bioindicators by assessing the presence and abundance of plastic within their stomach contents. The project hoped to fill some of the current gaps in knowledge on microplastics within Malta by creating a working baseline, as well as …

Alternatives To Laboratory Animals: Definition And Discussion, Andrew N. Rowan

Andrew N. Rowan, DPhil

The origins of the concept of "alternatives" to the use of animals in research may be traced back to the 1800's and the furore about using live animals in surgical and other experiments. Some of the animal protection societies in England were prepared to accept animal experimentation provided it was performed under anesthesia. Even Dr. Marshall Hall, who championed the spread of experimental medicine in 19th century England, considered it necessary to control and prevent unwarranted, inept and cruel experimentation (French, 1975). The concept of alternatives has developed in the 20th century to encompass not only the reduction (prevention) of …

Efficacy Of Natural Compounds With Novel Carrier Systems For Controlling Campylobacter Jejuni In Post-Harvest Poultry, Sandip Shrestha

Graduate Theses and Dissertations

Campylobacter jejuni, a leading cause of bacterial gastroenteritis worldwide, is strongly associated with the consumption and/or mishandling of raw contaminated poultry products. Thus, interventions aiming to reduce C. jejuni counts on poultry products could greatly reduce the incidence of human campylobacteriosis. In the first study, the efficacy of a generally recongnized as safe (GRAS) compound, carvacrol (CR; derived from oregano oil), as an antimicrobial wash treatment to reduce C. jejuni on chicken skin was evaluated. Three delivery systems of CR: suspension, emulsion and nanoemulsion were used. C. jejuni counts were reduced up to 4 log10 cfu/sample by 2% dose of …

Study Of Three Potential Variables That May Impact The Maximum Shear Force And Shear Variation During The Growth And Transport Of Mixed Sex Broilers Grown In Commercial Poultry Houses, Mark Christie

Graduate Theses and Dissertations

Temperature conditions during the transportation to the processing facility of commercial broilers have a direct impact on the meat texture, specifically maximum shear force and shear variation of cooked breast meat. Analysis of a calendar year of flock data (N=346), reveals that the largest impact of transport conditions, specifically temperature, is on the standard deviation of the flocks range of cooked shear values. The optimal transport temperature that yields broiler breast meat with average flock minimum shear and standard deviation values is approximately 60°F. The shear values for flocks at or near 60°F are on average 1 kg less than …

Optimizing Methods To Determine Metabolizable Energy Values Of Feed Ingredients For Broilers, Skyler P. West

Graduate Theses and Dissertations

Determination of metabolizable energy (ME) and amino acid (AA) digestibility values of single feed indigents continues to be two of the most important aspects for successful least-cost poultry feed formulation. It would be advantageous if a common diet type could be utilized to determine both ME and AA digestibility values of feed ingredients within a single assay. Two experiments were conducted to evaluate the effect of basal diet type and excreta collection method on the ME value of single feed ingredients determined in broiler chicks using the regression method. In experiment 1, the objective was to investigate the influence of …

A Two Compartment Pharmacokinetic Model Describes The Intra‐Articular Delivery And Retention Of Rhprg4 Following Acl Transection In The Yucatan Mini Pig, Mark Hurtig, Iman Zaghoul, Heather Sheardown, Tannin A. Schmidt, Lina Liu, Ling Zhang, Khaled A. Elsaid, Gregory D. Jay

Pharmacy Faculty Articles and Research

Treatment of the injured joint with rhPRG4 is based on recent observations that inflammation diminishes expression of native PRG4. Re‐establishing lubrication between pressurized and sliding cartilage surfaces during locomotion promotes the nascent expression of PRG4 and thus intra‐articular (IA) treatment strategies should be supported by pharmacokinetic evidence establishing the residence time of rhPRG4. A total of 21 Yucatan minipigs weighing ∼55 Kg each received 4 mg of 131I‐rhPRG4 delivered by IA injection 5 days following surgical ACL transection. Animals were sequentially euthanized following IA rhPRG4 at 10 mins (time zero), 24, 72 hrs, 6, 13 and 20 days later. The …

No Evidence For Kin Protection In The Expression Of Sickness Behaviors In House Mice, Patricia C. Lopes, Per Block, Alice Pontiggia, Anna K. Lindholm, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

When infected, animals change their behaviors in several ways, including by decreasing their activity, their food and water intake, and their interest in social interactions. These behavioral alterations are collectively called sickness behaviors and, for several decades, the main hypotheses put forward to explain this phenomenon were that engaging in sickness behaviors facilitated the fever response and improved the likelihood of host survival. However, a new hypothesis was recently proposed suggesting that engaging in sickness behaviors may serve to protect kin. We tested this kin protection hypothesis by combining a field and a laboratory experiment in house mice. In both …

Development Of A Pd-L1 Pet Imaging Biomarker, Caleb Jack Bridgwater

Posters-at-the-Capitol

Immunotherapy strategies are very promising treatments for cancer patients. Specifically, Immune checkpoint inhibitor therapy focusing on the PD-1/PD-L1 pathway shows long-lasting positive results in many cancer patients. Unfortunately, not all the patients can benefit from this highly effective treatment. Hence, there is a great need for predictive biomarkers. Immunohistochemical (IHC) staining has been used as a way of predicting patient response, yet shows many problems. For example, IHC utilizes an invasive biopsy and sample fixing, which creates an incomplete and delayed picture of the patient’s biochemistry and the tumor microenvironment, consequently ignoring metastases.

The purpose of this study is to …

Applications Of Drosophila Melanogaster In Food Science Research, Phoebe Beverly Chen

Doctoral Dissertations

Drosophila melanogaster is a versatile model organism that provides several unique features, such as highly conserved disease pathways with humans as well as availability of environmental and genetic manipulations. Meanwhile, there is increasing interest in the potential role of bioactive food components, epigallocatechin gallate (EGCG) and conjugated linoleic acid (CLA), in metabolic research. However, there is limited knowledge on the sex-dependent effects of EGCG and CLA on energy metabolism. In this study, Drosophila melanogaster was used to investigate the sex-dependent effects of EGCG and CLA with respect to energy metabolism, including body fat, locomotion, and their key metabolic regulators. We …

Resource Assessment Report Temperate Demersal Elasmobranch Resource Of Western Australia, Matias Braccini, Nick Blay, S. A. Hesp, Brett Molony

Fisheries research reports

This document provides a cumulative description and assessment of the TDER and all of the fishing activities (i.e. fisheries / fishing sectors) affecting this resource in WA. Future Resource Assessment Reports will assess the Statewide Sharks and Rays Resource. The report is focused on the temperate indicator species (whiskery, gummy, dusky and sandbar sharks) used to assess the suites of demersal sharks and rays that comprise this resource. These species are primarily captured by demersal gillnets used in the TDGDLF that operate in the West Coast and South Coast Bioregions. For the North Coast bioregion, no commercial fishing for sharks …

Diffusion Through The Ex Vivo Vitreal Body – Bovine, Porcine, And Ovine Models Are Poor Surrogates For The Human Vitreous, Sara Shafaie, Victoria Hutter, Marc B. Brown, Michael T. Cook, David Y.S. Chau

Pharmacology and Animal Models in Research Collection

The human vitreous humour is a complex gel structure whose composition and physical properties can vary considerably from person to person and also change with age. To date, the viscoelastic properties of the human vitreous gel has not been thoroughly investigated and despite many years of intensive research, an ideal vitreous substitute remains a challenge. Understanding the physical structure and properties of the vitreous is of fundamental and therapeutic interest, providing a clear insight into diffusion and transport of administered ophthalmic drug molecules into the vitreous. A number of mammalian surrogates, mainly bovine, porcine and ovine vitreous humours have been …

Impacts Of Climate Change And Bioenergy Markets On The Profitability Of Slash Pine Pulpwood Production In The Southeastern United States, Andrea Susaeta, Pankaj Lal

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

In this study, we assessed the impacts of climate change on the production of pulpwood and biomass for bioenergy, and the profitability of slash pine stands in the Southeastern United States. We employed the 3-PG (Physiological Processes Predicting Growth) model to determine the effects of future climates on forest growth and integrated it with a stand-level economic model to determine their impacts on optimal forest management. We found that the average production of pulpwood increased for all sites by 7.5 m³ ha⁻¹ for all climatic scenarios and productivity conditions. In the case of forest biomass for bioenergy, the …

A Cohort-Based Program To Help Students Prepare A Conference Research Presentation, Alanna Lecher

Florida Statewide Symposium: Best Practices in Undergraduate Research

Students move through many first time experiences when navigating their undergraduate and graduate education. Such experiences include the first time students submit an article to a peer-reviewed scientific journal, attend a conference, and conduct fieldwork. The cohort model has been shown to be effective in increasing success in undergraduate education, and it can be adapted to helping students succeed in these novel experiences as well. This presentation will explore one program where the cohort model was implemented to aid undergraduate students preparing their first conference presentation on a scientific research project. Program structure and implementation will be described.

Cannabinoid Transmission In The Basolateral Amygdala Modulates Prefrontal Cortex And Ventral Hippocampal Activity, Brian J. Pereira

Electronic Thesis and Dissertation Repository

The cannabinoid system is important for maintaining neuron-to-neuron communication within the mammalian brain. One of the most commonly used substances to alter the cannabinoid system is cannabis. Individuals who are exposed to cannabis report having dissociable effects; both positive and negative. High amounts of THC have been commonly associated with the negative effects of cannabis, whereas CBD can be used to counter these. Pre-clinical evidence suggests that the combination of the two compounds can produce a therapeutic benefit for individuals who are susceptible to the effects of THC. The present study investigates whether the combination of THC+CBD can prevent electrophysiological …

Factors Affecting Gastropod Larval Development And Performance: A Systematic Review, Maria Rosa, Dianna K. Padilla, David Charifson, Alyssa Liguori, Mica Mccarty-Glenn, Allison Rugila

Biology Faculty Publications

The goal of this article was to use a systematic review of studies on the larval stages of gastropods reared to metamorphosis to determine whether there are general patterns for the effects of temperature, rearing density, and food availability on larval development and performance among species, major taxa, and modes of development. Most studies did not include sufficient metadata to be included in many of the analyses. For all analyses, there were differences among major groups of taxa in terms of response to the considered variables. Increased temperature was frequently correlated with decreased development time and increased growth but often …

Research And Publication: Are We Moving In The Right Direction, A Khan, Rehana Rehman, Saara Ahmad

Department of Biological & Biomedical Sciences

No abstract provided.

The Role Of Cholinergic Signaling In Cardiac Function, Rachel Reingold

Electronic Thesis and Dissertation Repository

Cardiovascular disease is one of the leading causes of death in Canada. Treatment currently focuses on preventing the increase of sympathetic signaling seen in heart failure. However, it has recently been noted that cardiac function is dependent on parasympathetic tone. Previous studies have demonstrated the development of heart failure when cholinergic targets are knocked out in cardiomyocytes. Transgenic mouse models that have increased cholinergic transmission show protection against cardiovascular insults. We have shown that transgenic mice overexpressing vesicular acetylcholine transporter in cholinergic cells show cardiovascular protection in response to ex vivo insults. As well, this protection is seen when cholinergic …

Brain Endothelial Erythrophagocytosis And Hemoglobin Transmigration Across Brain Endothelium: Implications For Pathogenesis Of Cerebral Microbleeds, Rudy Chang, Juan Castillo, Alexander C. Zambon, Tatiana B. Krasieva, Mark J. Fisher, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Peripheral endothelial cells are capable of erythrophagocytosis, but data on brain endothelial erythrophagocytosis are limited. We studied the relationship between brain endothelial erythrophagocytosis and cerebral microhemorrhage, the pathological substrate of MRI-demonstrable cerebral microbleeds. To demonstrate the erythrophagocytic capability of the brain endothelium, we studied the interactions between brain endothelial cells and red blood cells exposed to oxidative stress in vitro, and developed a new in vitro cerebral microbleeds model to study the subsequent passage of hemoglobin across the brain endothelial monolayer. Using multiple approaches, our results show marked brain endothelial erythrophagocytosis of red blood cells exposed to oxidative stress compared …

Role Of Intrinsic Disorder In Animal Desiccation Tolerance, Brett Janis, Clinton Belott, Michael Menze

Faculty Scholarship

This review compares the molecular strategies employed by anhydrobiotic invertebrates to survive extreme water stress. Intrinsically disordered proteins (IDPs) play a central role in desiccation tolerance in all species investigated. Various hypotheses about the functions of anhydrobiosisrelated intrinsically disordered (ARID) proteins, including late embryogenesis abundant (LEA) and tardigrade-specific intrinsically disordered proteins, were evaluated by broad sequence characterization. A surprisingly wide range in sequence characteristics including hydropathy and the frequency and distribution of charges was discovered. Interestingly, two clusters of similar proteins were found that potentially correlate with distinct functions. This may indicate two broad groups of ARID proteins, composed of …

Uplc-Ms/Ms Analysis Of Dextromethorphan-O-Demethylation Kinetics In Rat Brain Microsomes, Barent N. Dubois, Reza Mehvar

Pharmacy Faculty Articles and Research

Formation of dextrorphan (DXT) from dextromethorphan (DXM) has been widely used to assess cytochrome P450 2D (CYP2D) activity. Additionally, the kinetics of CYP2D activity have been well characterized in the liver microsomes. However, studies in brain microsomes are limited due to the lower microsomal content and abundance of CYP2D in the brain relative to the liver. In the present study, we developed a micro-scale enzymatic incubation method, coupled with a sensitive UPLC-MS/MS assay for the quantitation of the rate of DXT formation from DXM in brain microsomes. Rat brain microsomes were incubated with different concentrations of DXM for various times. …

Measurement And Protection Of Lung Health In Poultry Farmers Of Southwestern Ontario, Rose-Marie Doyon Dolinar

Electronic Thesis and Dissertation Repository

Chronic obstructive lung disease (COPD), develops gradually, and tends to be noticed by farmers only after there has been a significant loss of lung function. People with symptoms of COPD often present for health care in later stages of disease, because they accept cough or breathlessness as “normal”.

Measurement of lung health for those at risk of developing COPD provides an opportunity for early detection of lung disease, and deter the progression toward irreversible damage to the lungs. COPD is, however, under-diagnosed.

The importance of bringing primary care providers and farmers together, and acknowledging the high-risk nature of occupational exposures, …

Green Tea Polyphenol Epigallocatechin-3-Gallate-Stearate Inhibits The Growth Of Streptococcus Mutans: A Promising New Approach In Caries Prevention, Amy Lynn Melok, Lee Lee, Siti Ayuni Mohamed Yussof, Tinchun Chu

Department of Biology Faculty Scholarship and Creative Works

Streptococcus mutans (S. mutans) is the main etiological bacteria present in the oral cavity that leads to dental caries. All of the S. mutans in the oral cavity form biofilms that adhere to the surfaces of teeth. Dental caries are infections facilitated by the development of biofilm. An esterified derivative of epigallocatechin-3-gallate (EGCG), epigallocatechin-3-gallate-stearate (EGCG-S), was used in this study to assess its ability to inhibit the growth and biofilm formation of S. mutans. The effect of EGCG-S on bacterial growth was evaluated with colony forming units (CFU) and log reduction; biofilm formation was qualitatively determined by Congo red assay, …

First Record Of The Genus Leptodactylus (Anura: Leptodactylidae) In Cuba: Leptodactylus Fragilis, A Biological Invasion?, Tomás M. Rodríguez-Cabrera, L. Yusnaviel García-Padrón, Andrés R. Acosta Galvis, Rafael O. De Sá, Roberto Alonso Bosch

Biology Faculty Publications

The Neotropical genus Leptodactylus is currently represented by three species in the West Indies (Leptodactylus albilabris, Leptodactylus fallax and Leptodactylus validus). Based on morphological, acoustic and molecular evidence, we document the presence of a fourth species in the Caribbean region, Leptodactylus fragilis (Brocchi, 1877). The species was found at two localities in western Cuba, and molecular data suggest a northern South American origin, possibly Venezuela, for these populations. We discuss the potential invasive status of L. fragilis, based on its known distribution, relative abundance, behaviour and possible impacts on native species of Cuban amphibians.

Targeting Neuropeptides To Bone Fractures For Accelerated Healing, Nicholas A. Young, Jeffery J. Nielsen, Philip S. Low

The Summer Undergraduate Research Fellowship (SURF) Symposium

In patients over the age of 65 especially, bone fractures represent a significant disease burden. Non-invasive drug therapies are not available for bone fractures which represents a problem for this population. Vasoactive intestinal peptide (VIP) and Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP), two neuromodulator peptides in the glucagon superfamily, have demonstrated positive regulation of osteoblast proliferation and activity. Using acidic oligopeptides, we have developed ligands that target to and accumulate at fracture sites. These targeting ligands can be synthesized in sequence with bone anabolic peptides to minimize off target effects and increase potency at the fracture site to create safer and …

Investigation Of Zebrafish Larvae Behavior As Precursor For Suborbital Flights: Feasibility Study, Pedro Llanos, Kristina Andrijauskaite, Mark Rubinstein, Sherine S.L. Chan

Pedro J. Llanos (www.AstronauticsLlanos.com)

Identifying The 5’End Of The Camta1 Genes In Zebrafish, Morgan Fronk

Undergraduate Honors Theses

Congenital heart diseases (CHDs) are a significant cause of infant death and are frequently caused by mutations in transcription factors. Camta1 (calmodulin binding transcription activator 1) is a transcription factor that has been proposed as a modulator in embryonic heart development and a possible cause of CHDs. The only other known member of its family in vertebrates is involved in activating a hypertrophy gene program in adult heart failure. Unlike camta2, camta1 is expressed in the embryonic heart during heart looping. However, few studies have been done on camta1. In zebrafish, there are two camta1 ohnologs (homologs created through …