Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 16 of 16

Full-Text Articles in Life Sciences

Response Of Soil Nitrification To The Veterinary Pharmaceuticals Monensin, Ivermectin And Zinc Bacitracin, Magda A. Konopka Dec 2014

Response Of Soil Nitrification To The Veterinary Pharmaceuticals Monensin, Ivermectin And Zinc Bacitracin, Magda A. Konopka

Electronic Thesis and Dissertation Repository

Pharmaceutical residues can reach agricultural land through amendment with animal or human waste. Since 2010, a series of replicated plots received annual applications of ivermectin, monensin and zinc bacitracin, either singly or in a mixture, at 0.1 mg/kg and 10 mg/kg concentrations. I collected soil samples before and after the fourth annual application of pharmaceuticals and assayed them for functional changes and amoA gene abundance, a gene needed for ammonia oxidation. In 2013, I exposed the soils to 100 mg/kg in a laboratory experiment which resulted in acceleration of nitrification. Under 10 mg/kg treatments in the field the abundance of …


Acquisition And Reconstruction Techniques For Fat Quantification Using Magnetic Resonance Imaging, Abraam S. Soliman Nov 2014

Acquisition And Reconstruction Techniques For Fat Quantification Using Magnetic Resonance Imaging, Abraam S. Soliman

Electronic Thesis and Dissertation Repository

Quantifying the tissue fat concentration is important for several diseases in various organs including liver, heart, skeletal muscle and kidney. Uniquely, MRI can separate the signal from water and fat in-vivo, rendering it the most suitable imaging modality for non-invasive fat quantification. Chemical-shift-encoded MRI is commonly used for quantitative fat measurement due to its unique ability to generate a separate image for water and fat. The tissue fat concentration can be consequently estimated from the two images. However, several confounding factors can hinder the water/fat separation process, leading to incorrect estimation of fat concentration.

The inhomogeneities of the main …


Identification And Characterization Of Cysteine Protease Genes In Tobacco For Use In Recombinant Protein Production, Kishor Duwadi Aug 2014

Identification And Characterization Of Cysteine Protease Genes In Tobacco For Use In Recombinant Protein Production, Kishor Duwadi

Electronic Thesis and Dissertation Repository

Plants are an attractive host system for pharmaceutical protein production. Many therapeutic proteins have been produced and scaled up in plants at a low cost compared to the conventional microbial and animal based systems. The main technical challenge during this process is to produce sufficient level of proteins in plants. Low yield is generally caused by proteolytic degradation during expression and downstream processing of recombinant proteins. The yield of a human therapeutic protein interleukin (IL) -10 produced in transgenic tobacco leaves was found to be below the critical level, and is potentially due to degradation by tobacco cysteine proteases (CysPs). …


The Effects Of Oar-Shaft Stiffness And Length On Rowing Biomechanics, Brock Laschowski Aug 2014

The Effects Of Oar-Shaft Stiffness And Length On Rowing Biomechanics, Brock Laschowski

Electronic Thesis and Dissertation Repository

This work investigates the effects of oar-shaft stiffness and length on rowing biomechanics. The mechanical properties of the oar-shafts were examined using an end-loaded cantilever system, and theoretical relations were proposed between the mechanics of the oar-shafts and rowing performance. On-water experiments were subsequently conducted and rowing biomechanics measured via the PowerLine Rowing Instrumentation System. The PowerLine system measures force and oar angle on the oarlock, as well as proper boat acceleration. The convergent validity and test-retest reliability of the PowerLine force measurements were determined prior to the on-water experiments. Thereafter, rowers were tested over a set distance using oar-shafts …


Transcriptional Regulation Of Peptidylarginine Deiminase Type Iv: Implications For Rheumatoid Arthritis, Ali Abbas Aug 2014

Transcriptional Regulation Of Peptidylarginine Deiminase Type Iv: Implications For Rheumatoid Arthritis, Ali Abbas

Electronic Thesis and Dissertation Repository

High titers of anti-citrullinated protein antibodies have been detected in sera of rheumatoid arthritis (RA) patients, implicating citrullinating enzymes in the pathogenesis of RA. Peptidylarginine deiminase type IV (PAD4) is a member of the PAD family of enzymes that catalyze the post- translational modification of arginine to citrulline and has been linked with RA. However, little is known about its transcriptional regulation. Therefore, our aim was to determine how transcription of PAD4 is activated in the myeloid lineage. Using bioinformatics, a potential nuclear factor kappa B (NF-kB) binding site was identified on the PAD4 promoter. Luciferase assays were used to …


Genomic Predictors Of Drug Response To The Alpha-Specific Phosphoinositol 3-Kinase (Pi3ka-Alpha) Inhibitor Byl719 In Head And Neck Cancers, Giananthony T. Rizzo Jul 2014

Genomic Predictors Of Drug Response To The Alpha-Specific Phosphoinositol 3-Kinase (Pi3ka-Alpha) Inhibitor Byl719 In Head And Neck Cancers, Giananthony T. Rizzo

Electronic Thesis and Dissertation Repository

PIK3CA is the only frequently mutated, druggable oncogene in head and neck squamous cell cancer (HNSCC), with PIK3CA point mutations and gene amplification rates of 17.5% and 40% respectively, with higher rates in HPV-positive disease. The objective of this research was to determine the effects of BYL719, an α-specific PI3K inhibitor in HNSCC cell lines.

All cell lines with PIK3CA hotspot point mutations or gene amplifications will be sensitive to BYL719.

Twenty-eight HNSCC cell lines were subjected to increasing concentrations of BYL719 and cell viability was measured over time. Cell lines were screened for activating PIK3CA hotspot mutations and amplifications …


Probiotic Therapy For Heart Failure: Investigating The Potential Anti-Hypertrophic Properties Of Probiotics, Grace L. Ettinger Jul 2014

Probiotic Therapy For Heart Failure: Investigating The Potential Anti-Hypertrophic Properties Of Probiotics, Grace L. Ettinger

Electronic Thesis and Dissertation Repository

Heart failure patients face a five-year 50% mortality rate, due to impaired cardiac function and hypertrophy of the heart. Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. Considering the established cardiovascular benefits of some probiotics, including reduction of cholesterol and hypertension, it was hypothesized that probiotics can improve outcomes of heart failure. Probiotics or controls were administered orally to an animal model for heart failure. Those receiving probiotics showed a significant improvement in cardiac hypertrophy and an attenuation of heart failure compared to control. No changes in gut microbial composition occurred. …


A Non-Contrast Magnetic Resonance Imaging Technique To Assess Blood-Brain Barrier Permeability, Harini Pandithasekera Jun 2014

A Non-Contrast Magnetic Resonance Imaging Technique To Assess Blood-Brain Barrier Permeability, Harini Pandithasekera

Electronic Thesis and Dissertation Repository

The Blood-brain barrier (BBB) regulates the entry of compounds between the blood and the brain, thus plays an important role in brain homeostasis. Studies indicate in disease states such as Alzheimer’s the BBB integrity is compromised. The motive of this project is to investigate the sensitivity of the diffusion-weighted arterial spin labeling (DW-ASL) technique to detect water exchange. Testing the sensitivity requires a reliable method of opening the barrier at specific locations of the brain. Here, a unique technology named focused ultrasound (FUS) has been used to mimic a compromised BBB environment.

A series of experiments were conducted in a …


Quantifying The Effect Of Age And Contraction Mode On The Force-Velocity-Power Relationship In The Knee Extensors, Justin R. Paturel May 2014

Quantifying The Effect Of Age And Contraction Mode On The Force-Velocity-Power Relationship In The Knee Extensors, Justin R. Paturel

Electronic Thesis and Dissertation Repository

PURPOSE: To assess and compare the force-velocity-power relationship (F-V-P) using isotonic and isokinetic knee extensions in 11 younger (19-30y) and 11 older (69-81y) men. METHODS: The construction of the F-V-P curves were attained with each participant performing maximal, explosive knee extensions at 8 different loads (isotonic) and 8 different velocities (isokinetic) on a Cybex HUMAC NORM dynamometer. Maximal voluntary contraction (MVC or Po), maximal shortening velocity (Vmax), maximum power, optimal torque (Popt) and velocity (Vopt) were assessed and compared. RESULTS: The older men were 43% weaker, 18% slower and ~54% less powerful …


Economic Evaluation Of Potential Applications Of Gene Expression Profiling In Clinical Oncology, Malek Hannouf Apr 2014

Economic Evaluation Of Potential Applications Of Gene Expression Profiling In Clinical Oncology, Malek Hannouf

Electronic Thesis and Dissertation Repository

Histopathological analysis of tumor is currently the main tool used to guide cancer management. Gene expression profiling may provide additional valuable information for both classification and prognostication of individual tumors. A number of gene expression profiling assays have been developed recently to inform therapy decisions in women with early stage breast cancer and help identify the primary tumor site in patients with metastatic cancer of unknown primary. The impact of these assays on health and economic outcomes, if introduced into general practice, has not been determined. I aimed to conduct an economic evaluation of regulatory-approved gene expression profiling assays for …


The Effects Of Ocean Acidification And Eutrophication On The Growth, Lipid Composition And Toxicity Of The Marine Raphidophyte Heterosigma Akashiwo., Julia Rose Matheson Apr 2014

The Effects Of Ocean Acidification And Eutrophication On The Growth, Lipid Composition And Toxicity Of The Marine Raphidophyte Heterosigma Akashiwo., Julia Rose Matheson

Electronic Thesis and Dissertation Repository

Anthropogenic forcing, such as ocean acidification caused by rising carbon dioxide emissions, and eutrophication due to increased nutrient loadings in run-off, are causing major changes to the biogeochemistry of the oceans. As a consequence, coastal phytoplankton are susceptible to altered biogeochemical environments. This study examined the effect of a lower pH and increased levels of nutrients on the common coastal harmful alga, Heterosigma akashiwo. Growth rates, maximal cell yields, neutral lipid accumulation and toxicity of cells grown under various pH and nutrients regimes were measured. H. akashiwo growth was near maximal when grown at lower pH levels. There was …


Effect Of Ascorbate On Coagulation And Fibrinolytic Factors In The Septic Microvasculature, Scott Swarbreck Apr 2014

Effect Of Ascorbate On Coagulation And Fibrinolytic Factors In The Septic Microvasculature, Scott Swarbreck

Electronic Thesis and Dissertation Repository

Sepsis, a systemic inflammatory response to an infection, is a significant cause of morbidity and mortality worldwide. The microcirculation during sepsis fails, in part, due to microthrombosis and the resulting plugging of capillaries, precipitating organ failure. Intravenous injection of ascorbate has been shown to reduce capillary plugging, however the mechanism of this protective effect is unclear. We hypothesized that ascorbate-mediated destabilization of the microthrombi through promoting fibrinolysis could contribute to this protection.

We showed that streptokinase, a pro-fibrinolytic agent, reduced the capillary plugging to a similar degree as ascorbate. This similarity provided the impetus for studying the effect of ascorbate …


Interesting Shapes Of Vegetables: Is It A Strategy To Promote Consumption Among Preschool Children?, Salma H. Alhabshi Apr 2014

Interesting Shapes Of Vegetables: Is It A Strategy To Promote Consumption Among Preschool Children?, Salma H. Alhabshi

Electronic Thesis and Dissertation Repository

This study highlighted the low intake of vegetables by preschool children and determined whether changing the shape of vegetables increased their level of consumption. A new strategy of repeated exposure to interesting-shaped vegetables was a step aimed at increasing vegetable consumption by increasing the fun element in having vegetables as snacks. Vegetables are the less desirable food in comparison to more attractive unhealthy choices available to children, and discovering a strategy to promote vegetables is considered an important step in nutrition. The primary aim was to explore the effect of repeated exposure (eight times) of shaped vegetables on consumption by …


Development Of Non-Covalent Functionalization Of Carbon Nanotubes For Sirna Delivery, King Sun Siu Apr 2014

Development Of Non-Covalent Functionalization Of Carbon Nanotubes For Sirna Delivery, King Sun Siu

Electronic Thesis and Dissertation Repository

RNA interference (RNAi) therapy is promising for treating various diseases but the delivery of small interfering RNA (siRNA) is difficult. To overcome the technical difficulties of siRNA delivery, an efficient and targeted delivery of siRNA is required for efficient RNAi therapy. Single-walled carbon nanotubes (CNT) has been used for nucleic acid delivery such as siRNA delivery. It has been found that CNT can gain entry into the cells by a diffusion-like mechanism which was called “nano-needle”. However, the solubility of CNT is low in most of the solvents including water. Functionalization of CNT can be carried out to enhance the …


Functional Anatomy Of The Anconeus: Muscle Architecture And Motor Unit Number Estimation, Daniel E. Stevens Apr 2014

Functional Anatomy Of The Anconeus: Muscle Architecture And Motor Unit Number Estimation, Daniel E. Stevens

Electronic Thesis and Dissertation Repository

Exploring muscle architecture in vivo and estimating the number of MUs in the human anconeus muscle have important implications related to the neuromuscular function of this muscle as a model for study in health and disease. The two studies presented in this thesis investigate the functional anatomy of the anconeus in 10 healthy young men (25±3y).

Ultrasound imaging has facilitated the measure of the architectural variables, fascicle length (LF) and pennation angle (PA), in many human skeletal muscles in vivo. However, the functional anatomy of the anconeus has been investigated mainly from cadavers exclusively. Thus, the purpose …


The Role Of Oxygen Tension And Insulin-Like Growth Factor Signaling In The Placental Mesenchymal Stem Cell Fate, Amer Youssef Jan 2014

The Role Of Oxygen Tension And Insulin-Like Growth Factor Signaling In The Placental Mesenchymal Stem Cell Fate, Amer Youssef

Electronic Thesis and Dissertation Repository

The human placenta of different gestational ages is a readily available source for isolation of adult mesenchymal stem cell (MSC) for potential use in regenerative therapies. The chorionic villous region, the largest component of a placenta that interfaces with the maternal circulation, is a rich source of placental MSCs (PMSCs). To remain multipotent, PMSCs are best maintained in culture conditions that mimic the in vivo microenvironment. Insulin like growth factors (IGFs, IGF-I and -II) and oxygen tension are two of the most important microenvironmental factors in the placenta. They are of low concentration or tension respectively, at early gestation, and …