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The Relationship Between Vagal Tone, A Marker Of Parasympathetic Activity, And Pro-Social Behavior, Emily A. Goodlin Jan 2015

The Relationship Between Vagal Tone, A Marker Of Parasympathetic Activity, And Pro-Social Behavior, Emily A. Goodlin

Scripps Senior Theses

Vagal tone, a measure of parasympathetic activity via the vagus nerve, is known to be associated with positive emotion because it promotes social engagement and self-soothing behavior. Heart rate variability (HRV), especially high frequency oscillation, is a direct measure of vagal tone, and has been used in previous studies to test the correlation between vagal tone and positive emotion. This study aims to determine if the two major oscillations of heart rate variability, high frequency (HF-HRV) and low frequency (LF-HRV) can predict pro-social behavior, which is classified as giving donations to charities. Baseline LF- and HF-HRV levels were recorded, and …


L30a Mutation Of Phospholemman Mimics Effects Of Cardiac Glycosides On Isolated Cardiomyocytes, Ryan David Himes Jan 2015

L30a Mutation Of Phospholemman Mimics Effects Of Cardiac Glycosides On Isolated Cardiomyocytes, Ryan David Himes

Dissertations

In order to determine if mutations made to phospholemman (PLM) could increase PLM binding to the Na/K-ATPase (NKA) and cause positive inotropy we performed scanning mutagenesis of the transmembrane domain of PLM and measured FRET between each mutant and NKA. We observed increased binding to NKA for several PLM mutants compared to WT, including L27A, L30A, and I32A. In isolated cardiomyocytes, overexpression of WT PLM increased the amplitude of the Ca2+ transient compared to GFP control. Ca2+ transient amplitude was further increased by L30A PLM overexpression. L30A mutation also delayed Ca2+ extrusion and increased the duration of the cardiomyocyte contraction. …


Smooth-Muscle Bmal1 Participates In Blood Pressure Circadian Rhythm Regulation, Zhongwen Xie, Wen Su, Shu Liu, Guogang Zhao, Karyn Esser, Elizabeth A. Schroder, Mellani Lefta, Harald M. Stauss, Zhenheng Guo, Ming Cui Gong Jan 2015

Smooth-Muscle Bmal1 Participates In Blood Pressure Circadian Rhythm Regulation, Zhongwen Xie, Wen Su, Shu Liu, Guogang Zhao, Karyn Esser, Elizabeth A. Schroder, Mellani Lefta, Harald M. Stauss, Zhenheng Guo, Ming Cui Gong

Physiology Faculty Publications

As the central pacemaker, the suprachiasmatic nucleus (SCN) has long been considered the primary regulator of blood pressure circadian rhythm; however, this dogma has been challenged by the discovery that each of the clock genes present in the SCN is also expressed and functions in peripheral tissues. The involvement and contribution of these peripheral clock genes in the circadian rhythm of blood pressure remains uncertain. Here, we demonstrate that selective deletion of the circadian clock transcriptional activator aryl hydrocarbon receptor nuclear translocator-like (Bmal1) from smooth muscle, but not from cardiomyocytes, compromised blood pressure circadian rhythm and decreased blood …


Human Anatomy And Physiology Preparatory Course (1st Edition), Carlos Liachovitzky Jan 2015

Human Anatomy And Physiology Preparatory Course (1st Edition), Carlos Liachovitzky

Open Educational Resources

The overall purpose of this preparatory course textbook is to help students familiarize with some terms and some basic concepts they will find later in the Human Anatomy and Physiology I course.

The organization and functioning of the human organism generally is discussed in terms of different levels of increasing complexity, from the smallest building blocks to the entire body. This Anatomy and Physiology preparatory course covers the foundations on the chemical level, and a basic introduction to cellular level, organ level, and organ system levels. There is also an introduction to homeostasis at the beginning.


The Effect Of Scalp Tissue On Current Shunting During Anodal Transcranial Direct Current Stimulation (Tdcs), Mark Patrick Jackson Jan 2015

The Effect Of Scalp Tissue On Current Shunting During Anodal Transcranial Direct Current Stimulation (Tdcs), Mark Patrick Jackson

Browse all Theses and Dissertations

Transcranial Direct Current Stimulation (tDCS) has been used to treat various mental and neurological illnesses. Rodent models have been used to examine physiological changes in the brain after tDCS, as well as to develop safety standards. However, most animal tDCS studies implant an electrode on the brain, potentially altering the path of current during stimulation. Additionally, no studies have been completed specifically examining maximum safe anodal tDCS limits, and a pilot study conducted to determine an electrode montage to examine biological changes of learning and memory from anodal tDCS indicated brain lesion was occurring before a commonly cited lesion threshold …


Effects Of Breathing Cool Air During Cycling Exercise In The Heat, Christian B. Ridings Aug 2014

Effects Of Breathing Cool Air During Cycling Exercise In The Heat, Christian B. Ridings

Graduate Theses and Dissertations

INTRODUCTION: The purpose of this study was to establish the ability of the Core Cooler device to prevent rises in physiological heat strain of trained male cyclists during cycling exercise in the heat. METHODS: 15 healthy male cyclists cycled at 50-70% VO2max for 75 minutes in a heat chamber of 31°C & 55% RH while breathing through the Core Cooler device under three different conditions: 1:4 ratio without ice termed control (CN), 1:4 ratio with ice termed low intermittent (LI), and at 1:1 ratio with ice termed high intermittent (HI). Data collected every 15 minutes assessing intestinal temperature (TGI), heart …


The Effect Of Moderate Altitude On High Intensity Running Performance During A Game With Collegiate Female Soccer Players, Jonathan Bohner Jan 2014

The Effect Of Moderate Altitude On High Intensity Running Performance During A Game With Collegiate Female Soccer Players, Jonathan Bohner

Electronic Theses and Dissertations

Competition often requires teams that reside at sea level to compete against opponents whose residence is at a moderate altitude. This may pose a potential competitive disadvantage considering that moderate altitude may cause decrements in VO2max, distance covered, and time to exhaustion in endurance athletes. The purpose of this study was to examine the effect of altitude on game performance measures. Six NCAA Division I female soccer players (20.33 ± 1.21 y; 168 ± 6.45 cm; 62.5 ± 6.03 kg) were retrospectively examined. Comparisons were made between two competitions that were played at sea level (SL) within two weeks of …


The Adrenal Cortex Cell Line H295r Releases Interleukin-6, Timothy E. Lindsay, Dr. Allan M. Judd Sep 2013

The Adrenal Cortex Cell Line H295r Releases Interleukin-6, Timothy E. Lindsay, Dr. Allan M. Judd

Journal of Undergraduate Research

Up to this point, the study of adrenal glands has utilized mostly rat and bovine models. However, in the research of human physiology, human models are preferable to animal models. But human adrenal glands are difficult to obtain, and when they are obtained, experiments often have limited sample sizes. In addition, human adrenal glands available for research are often functionally altered by disease. Also, donors with healthy adrenal glands may be administered multiple pharmacological agents which modify adrenal functions. These obstacles show how a model that provides an unlimited quantity of tissue with consistent secretion patterns would take precedent over …


Effect Of Shear Stress On Ecnos Expression And Dilation In Soleus Feed Arteries, Blanca Perez, Jay L. Brewster, Jeffrey Jasperse Jul 2013

Effect Of Shear Stress On Ecnos Expression And Dilation In Soleus Feed Arteries, Blanca Perez, Jay L. Brewster, Jeffrey Jasperse

Featured Research

Shear stress causes artery dilation and increased expression of endothelial cell nitric oxide synthase (ecNOS) in coronary and placental arteries. We sought to determine the importance of shear stress in maintaining normal dilation and normal levels of ecNOS in rat soleus feed arteries (SFA). SFA were isolated from male Sprague-Dawley rats and cannulated for in vitro microscopy (Fig. 6). SFA were exposed to no shear stress, low shear stress, or high shear stress conditions for 4 hours. After 4 hours, endothelium-dependent dilation (acetylcholine: ACh) and endothelium-independent dilation (sodium nitroprusside: SNP) were tested. Arteries were then uncannulated, mRNA was isolated, and …


The Effect Of Skeletal Muscle Mass On Basal Metabolic Rate In College-Age Males 2013, Chase Vaughn May 2013

The Effect Of Skeletal Muscle Mass On Basal Metabolic Rate In College-Age Males 2013, Chase Vaughn

Master's Theses

There are many misconceptions within the fitness community. One such misconception is that an increase in muscle mass will have a large increase in basal metabolic rate, yet this may not be the best way for successful weight loss. The purpose of this study was to determine the strength of the correlation between skeletal muscle mass and basal metabolic rate. The hypothesis tested was that basal metabolic rate is strongly correlated with skeletal muscle mass. The participants were college-aged males (n =17). Skeletal muscle mass (SMM) was estimated using the skin-fold circumference model (SFCM): SMM (kg) = Ht (0.00744 CAG2 …


Teaching Physiology Online: Successful Use Of Case Studies In A Graduate Course, Giovanni Casotti, John T. Beneski, Maureen T. Knabb Mar 2013

Teaching Physiology Online: Successful Use Of Case Studies In A Graduate Course, Giovanni Casotti, John T. Beneski, Maureen T. Knabb

Biology Faculty Publications

No abstract provided.


Developmental Adaptation Hypothesis : Aerobic Capacity, Submaximal Arterial Saturation And Pulmonary Volumes In Peruvian Quechua Natives, Melisa Kiyamu Tsuchiya Jan 2013

Developmental Adaptation Hypothesis : Aerobic Capacity, Submaximal Arterial Saturation And Pulmonary Volumes In Peruvian Quechua Natives, Melisa Kiyamu Tsuchiya

Legacy Theses & Dissertations (2009 - 2024)

The Quechua populations have inhabited the Andes for hundreds of generations. The ability to thrive in this hostile environment, leading an active and healthy life has generated research questions about the special phenotype of Andean highlanders compared to their sea-level counterparts, such as their higher pulmonary volumes and their outstanding work capacity in spite of the challenge of oxygen transport and delivery in hypoxia. In high altitude natives, there have been two main explanations for the origins of the aforementioned traits: genetic adaptation through natural selection and developmental adaptation through the exposure to hypoxia during growth.


Long-Term Depression Of Excitatory Inputs To Gabaergic Neurons In The Ventral Tegmental Area, Philip J. Sandoval Dec 2012

Long-Term Depression Of Excitatory Inputs To Gabaergic Neurons In The Ventral Tegmental Area, Philip J. Sandoval

Theses and Dissertations

Dopamine cells within the ventral tegmental area of the brain are involved in motivation and reward. Drugs of abuse target these dopamine cells altering their activity and plasticity resulting in addiction. While dopamine cell activity is primarily involved in addiction, the GABA neurons in the VTA have also been shown to have an indirect role. By decreasing the activity of the inhibitory GABA inputs onto dopamine neurons abusive drugs can indirectly increase dopamine cell activity resulting in addictive behaviors. However, although GABA neurons are important in the perception of reward, much less is known about how the excitatory inputs to …


Gβγ Acts At An Inter-Subunit Cleft To Activate Girk1 Channels, Rahul Mahajan Oct 2012

Gβγ Acts At An Inter-Subunit Cleft To Activate Girk1 Channels, Rahul Mahajan

Theses and Dissertations

Heterotrimeric guanine nucleotide-binding proteins (G-proteins) consist of an alpha subunit (Gα) and the dimeric beta-gamma subunit (Gβγ). The first example of direct cell signaling by Gβγ was the discovery of its role in activating G-protein regulated inwardly rectifying K+ (GIRK) channels which underlie the acetylcholine-induced K+ current responsible for vagal inhibition of heart rate. Published crystal structures have provided important insights into the structures of the G-protein subunits and GIRK channels separately, but co-crystals of the channel and Gβγ together remain elusive and no specific reciprocal residue interactions between the two proteins are currently known. Given the absence of direct …


The Relationship Between Heart Rate Variability, Shooting Experience, And Tactical Pistol Performance, Andrew Gerard Thompson Oct 2012

The Relationship Between Heart Rate Variability, Shooting Experience, And Tactical Pistol Performance, Andrew Gerard Thompson

Human Movement Studies & Special Education Theses & Dissertations

PURPOSE: At rest and during a tactical pistol competition classifier, heart rate variability (HRV) time-domain, high frequency (HF), low frequency (LF), total power (TP), and inter-beat-interval (IBI) measurements were examined in 28, healthy subjects (37 ± 11 yr old, 180 ± 7 cm, 90.6 ± 16.9 kg) for correlations to performance. METHODS: Resting measurements were taken supine in a quiet, dimmed room, during metronomic breathing. The shooting task consisted of three stages, comprised of several strings each. The strings were initiated by a starting buzzer and involved several tactical maneuvers, including holster draws, engaging multiple targets, firing on the move, …


Membrane Properties Involved In Calcium-Stimulated Microparticle Release From The Plasma Membranes Of S49 Lymphoma Cells, Lauryl Elizabeth Campbell Aug 2012

Membrane Properties Involved In Calcium-Stimulated Microparticle Release From The Plasma Membranes Of S49 Lymphoma Cells, Lauryl Elizabeth Campbell

Theses and Dissertations

The mechanism of microparticle shedding from the plasma membrane of calcium-loaded cells has been investigated in erythrocytes and platelets. Recent studies have revealed the physiological and clinical importance of microparticle release from nucleated cells such as lymphocytes and endothelium. The experiments of this study were designed to address whether simple mechanisms discovered in platelets and erythrocytes also apply to the more complex nucleated cells. Four such mechanisms were addressed: potassium efflux, transbilayer phosphatidylserine migration, cytoskeleton degradation, and membrane lipid order. The rate and amount of microparticle release in the presence of a calcium ionophore, ionomycin, was assayed by light scatter …


Spatial Distribution And Modulation Of Nitric Oxide Synthase In A Hypertensive Rat Model, Andrew Yannaccone Feb 2012

Spatial Distribution And Modulation Of Nitric Oxide Synthase In A Hypertensive Rat Model, Andrew Yannaccone

Theses and Dissertations

There are gaps in the fundamental understanding of the expression of nitric oxide synthases (NOS) in the microvasculature. We examined co-localization of NOS1 (nNOS), NOS2 (iNOS) and NOS3 (eNOS) in the spinotrapezius muscle of young adult male Wistar-Kyoto (WKY) and Spontaneously Hypertensive (SHR) rats according to fiber type using immunohistochemistry and brightfield microscopy. Data regarding fiber distribution, population and morphology data were collected. Alkaline phosphatase staining was used to determine capillary density and average number of capillaries around a fiber. Gel electrophoresis and Western blot techniques were used to compare myosin heavy chain (MHC) protein expression with fiber type population …


Aging, Neuromuscular Decline, And The Change In Physiological And Behavioral Complexity Of Upper-Limb Movement Dynamics, S. Morrison, K. M. Newell Jan 2012

Aging, Neuromuscular Decline, And The Change In Physiological And Behavioral Complexity Of Upper-Limb Movement Dynamics, S. Morrison, K. M. Newell

Rehabilitation Sciences Faculty Publications

Aging is characterized by a general decline in physiological and behavioral function that has been widely interpreted within the context of the loss of complexity hypothesis. In this paper, we examine the relation between aging, neuromuscular function and physiological-behavioral complexity in the arm-hand effector system, specifically with reference to physiological tremor and isometric force production. Experimental findings reveal that the adaptive behavioral consequences of the aging-related functional decline in neurophysiological processes are less pronounced in simple motor tasks which provides support for the proposition that the motor output is influenced by both extrinsic (e.g., task related) and intrinsic (e.g., coordination, …


Ischemia Impairs Vasodilation In Skeletal Muscle Resistance Artery, Kyle Remington Struthers Jun 2011

Ischemia Impairs Vasodilation In Skeletal Muscle Resistance Artery, Kyle Remington Struthers

Master's Theses

Functional vasodilation in arterioles is impaired with chronic ischemia. We sought to examine the impact of chronic ischemia and age on skeletal muscle resistance artery function. To examine the impact of chronic ischemia, the femoral artery was resected from young (2-3mo) and adult (6-7mo) mice and the profunda femoris artery diameter was measured at rest and following gracilis muscle contraction 14 days later using intravital microscopy. Functional vasodilation was significantly impaired in ischemic mice (14.4±4.6% vs. 137.8±14.3%, p<0.0001 n=8) and non-ischemic adult mice (103.0±9.4% vs. 137.8±14.3%, p=0.05 n=10). In order to analyze the cellular mechanisms of the impairment, a protocol was developed to apply pharmacological agents to the experimental preparation while maintaining tissue homeostasis. Endothelial and smooth muscle dependent vasodilation were impaired with ischemia, 39.6 ± 13.6% vs. 80.5 ± 11.4% and 43.0 ± 11.7% vs. 85.1 ± 10.5%, respectively. From this data, it can be supported that smooth muscle dysfunction is the reason for the observed impairment in arterial vasodilation.


The Effect Of Energy Patches On Substrate Utilization In Collegiate Cross-Country Runners, Ryan E. Fiddler, Doug Smith, Bert Jacobson, Crishel Klein, Aric Warren, Matt O'Brien, Brennan Thompson, Lee Everett Apr 2011

The Effect Of Energy Patches On Substrate Utilization In Collegiate Cross-Country Runners, Ryan E. Fiddler, Doug Smith, Bert Jacobson, Crishel Klein, Aric Warren, Matt O'Brien, Brennan Thompson, Lee Everett

International Journal of Exercise Science

It is well established that an increased capacity of skeletal muscle to oxidize fatty acids can spare glycogen and delay the onset of fatigue in mild- to moderate-intensity exercise. The purpose of the following study was to examine the effect of LifeWave® energy patches on non-protein substrate utilization in Division-1 cross-country runners. To determine the effect of the patches subjects were pretested to establish baselines and randomly assigned to an experimental (EX) or placebo (PL) group. Twenty-two trained male (n = 11; mean ± SD, age = 21.1 ± 2.6years, height = 179.6 ± 4.2cm, body mass = 71.4 ± …


Elucidating Functional Roles For Myogenin In Adult Skeletal Muscle Metabolism, Exercise Capacity, And Regeneration, Jesse Flynn Dec 2010

Elucidating Functional Roles For Myogenin In Adult Skeletal Muscle Metabolism, Exercise Capacity, And Regeneration, Jesse Flynn

Dissertations and Theses (Open Access)

The four basic helix-loop-helix myogenic transcription factors, myogenin, Myf5, MRF4, and MyoD are critical for embryonic skeletal muscle development. Myogenin is necessary for the terminal differentiation of myoblasts into myofibers during embryogenesis, but little is known about the roles played by myogenin in adult skeletal muscle function and metabolism. Furthermore, while metabolism is a well-studied physiological process, how it is regulated at the transcriptional level remains poorly understood. In this study, my aim was to determine the function of myogenin in adult skeletal muscle metabolism, exercise capacity, and regeneration. To investigate this, I utilized a mouse strain harboring the Myogflox …


Role Of Ampk In The Upregulation Of Steroidogenic Acute Regulatory Protein In The Zona Fasciculata Of The Adrenal Cortex, Adam Wesley Dayton Aug 2010

Role Of Ampk In The Upregulation Of Steroidogenic Acute Regulatory Protein In The Zona Fasciculata Of The Adrenal Cortex, Adam Wesley Dayton

Theses and Dissertations

Cortisol is a glucocorticoid produced by the zona fasciculata (ZF) of the adrenal cortex. Traditionally, cortisol production and release was seen as being regulated strictly by adrenocorticotropic hormone (ACTH). While this is true of baseline cortisol levels and in response to acute mental stress, the picture is somewhat more complicated in other situations.Interleukin-6 (IL-6) contributes to the maintenance of cortisol levels in situations of prolonged immune or inflammatory stress. AMP activated protein kinase (AMPK) was investigated as a possible mediator of the action of IL-6 or as an independent actor in raising cortisol levels in response to hypoxemic or hypoglycemic …


Human Physiology Community Education, Sasha Volgamore, Kristen Mitchell Apr 2010

Human Physiology Community Education, Sasha Volgamore, Kristen Mitchell

Service-Learning Program

The purpose of our project was to educate community members of all age groups to provide them with a basic knowledge of the fundamental workings of the human body, with specific emphasis on skeletal muscle physiology and cardiovascular physiology. It is our hope that members of our target audiences will use this information for future self-directed inquiries into human physiology with regard to their own bodies. Regardless of their age, everyone can decide to eat healthier and live a more active lifestyle. With the knowledge we provided the community, we hope they will appreciate that a healthy lifestyle is paramount …


Head And Neck Embryology: An Overview Of Development, Growth And Defect In The Human Fetus, Allison Baylis May 2009

Head And Neck Embryology: An Overview Of Development, Growth And Defect In The Human Fetus, Allison Baylis

Honors Scholar Theses

The purpose of this research is to explore the growth and formation of the head and neck from embryological development through puberty in order to understand how this knowledge is necessary for the development of dental and medical treatments and procedures. This is a necessary aspect of the medical and dental school curriculum at the University of Connecticut Health Center Schools of Medicine and Dental Medicine that needs to be incorporated into the current study of embryology for first-year students. Working with Dr. Christine Niekrash, D.M.D, this paper will cover the embryology and growth of the head, face and oral …


Minimum Criteria For Dna Damage-Induced Phase Advances In Circadian Rhythms, Christian I. Hong, Judit Zámborszky, Attila Csikász-Nagy May 2009

Minimum Criteria For Dna Damage-Induced Phase Advances In Circadian Rhythms, Christian I. Hong, Judit Zámborszky, Attila Csikász-Nagy

Dartmouth Scholarship

Robust oscillatory behaviors are common features of circadian and cell cycle rhythms. These cyclic processes, however, behave distinctively in terms of their periods and phases in response to external influences such as light, temperature, nutrients, etc. Nevertheless, several links have been found between these two oscillators. Cell division cycles gated by the circadian clock have been observed since the late 1950s. On the other hand, ionizing radiation (IR) treatments cause cells to undergo a DNA damage response, which leads to phase shifts (mostly advances) in circadian rhythms. Circadian gating of the cell cycle can be attributed to the cell cycle …


An Examination Of Body Composition Measurement Methods In Children, Robert Kaplan May 2009

An Examination Of Body Composition Measurement Methods In Children, Robert Kaplan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction . Body-composition methods include underwater weighing (UWW), skinfold thickness (SKF), bioelectrical impedance (BIA), and the BOD POD. Although these techniques are used routinely, each has its inherent limitations, especially in children. Purpose . The purpose of this study was to examine the various methods of body composition in children. Methods . The body composition of 7 boys between the ages of 12-14 (13.1 +/- 1.1 years) was determined using the BOD POD, UWW, SKF, and BIA. Results . Percent body fat estimated from the BOD POD (21.9 +/- 7.8%BF) was not significantly different than the estimated percent fat from …


Successful Implementation Of Inquiry-Based Physiology Laboratories In Undergraduate Major And Nonmajor Courses, Giovanni Casotti, Loretta Rieser-Danner, Maureen T. Knabb Dec 2008

Successful Implementation Of Inquiry-Based Physiology Laboratories In Undergraduate Major And Nonmajor Courses, Giovanni Casotti, Loretta Rieser-Danner, Maureen T. Knabb

Biology Faculty Publications

No abstract provided.


Effect Of Different Resistance Exercise Methods On Post-Exercise Blood Pressure, Daniel Rodriguez†, Marcos D. Polito‡, Reury F.P. Bacurau‡, Jonato Prestes‡, Francisco L. Pontes Jr‡ Oct 2008

Effect Of Different Resistance Exercise Methods On Post-Exercise Blood Pressure, Daniel Rodriguez†, Marcos D. Polito‡, Reury F.P. Bacurau‡, Jonato Prestes‡, Francisco L. Pontes Jr‡

International Journal of Exercise Science

The aim of the present study was to evaluate the post-exercise blood pressure (BP) responses to two different methods of resistance exercise (RE, traditional multiple set and tri-set). Young adult men (n = 30, 19.6 &#; 0.7 years old; 76.0 ± 2.7 kg; 178.2 ± 6.7 cm; 90.5 ± 5.8 MBP) with six months of previous experience in RE were selected. The volunteers were randomly assigned into three groups (n = 10, each group): non-exercised control group (CON); multiple set group (MS); and a tri-set group (TRI). The TRI group performed three consecutive exercises (3 sets of 10 repetitions with …


Investigating And Modeling Possible Mechanisms By Which Healthy Cell Membranes Become Resistant To Hydrolysis By Secretory Phospholipase A2, Jennifer Nelson Jul 2008

Investigating And Modeling Possible Mechanisms By Which Healthy Cell Membranes Become Resistant To Hydrolysis By Secretory Phospholipase A2, Jennifer Nelson

Theses and Dissertations

Secretory phospholipase A2 (sPLA2) behaves differently toward the membranes of healthy cells compared to those of damaged or dying cells. The enzyme catalyzes rapid and sustained hydrolysis of compromised cells consistent with a simple catalytic mechanism. In contrast, when healthy cells are incubated with sPLA2, they become resistant to hydrolytic attack as manifest by three unusual observations: First, hydrolysis is transient and represents only a small fraction of the total membrane phospholipid content. Second, subsequent addition of sPLA2 fails to generate additional product. Third, the apparent potency of the enzyme to cause the membrane to be refractory is much greater …


Role Of Vegf-C In Proliferation And Migration In A Cancer Model, Emily Marie Benke Jan 2008

Role Of Vegf-C In Proliferation And Migration In A Cancer Model, Emily Marie Benke

Theses and Dissertations

Head and neck cancer ranks high among the most common cancers world wide. In addition, there is a high recurrence rate, as well as a high prevalence of loco-regional tumor spread. Among many factors contributing to metastasis is vascular endothelial cell growth factor C. VEGF-C is primarily an inducer of new lymph vessel formation, typically during embryogenesis; however, some advanced cancers show a significant increase in VEGF-C expression, suggesting a role in metastasis. In the current study, the effects of VEGF-C expression were tested in HN12 cells, which are highly metastatic and known to express high levels of the chemokine …