Tag: Poster 75

The Reliability of Ultrasound Imaging as a Tool with Which to Evaluate Muscular Activation in Patients with Impingement Syndrome

Presenter: Lauren Maloney

Faculty Mentor: Andy Karduna

Presentation Type: Poster 75

Primary Research Area: Science

Major: Human Physiology

Differences in muscular activation in the context of dysfunctional muscles has been a field of particular interest in diagnosing disorders and determining possible causes of musculoskeletal pathologies. Electromyography (EMG) is a technique that measures the electrical activity of muscles via electrodes, and is the most commonly used technique for assessing muscular activation. However, EMG is invasive and difficult to carry out easily in clinical settings. In this study, we evaluated ultrasound images of symptomatic and asymptomatic limbs of 30 patients with unilateral shoulder pain in comparison to a “gold standard” technique and found that ultrasound is a reliable and valid tool for determining muscular width of the supraspinatus. Using this data, we compared differences in muscular activation between symptomatic and asymptomatic limbs of patients.

Assay of Insulin-Stimulated Signaling by Flow Cytometry: Key Points of Regulation

Presenter(s): Shawn Melendy − Biochemistry

Faculty Mentor(s): Carrie McCurdy, Byron Hetrick

Poster 75

Research Area: Natural/Physical Science

Funding: UROP mini-grant, American Physiological Society Undergraduate Summer Research Fellowship Program

Type 2 Diabetes, an increasingly prevalent disease worldwide, is partially caused by a progressive loss of insulin response in adipose tissue and skeletal muscle. Multicolor flow cytometry is a powerful tool that can be used to measure multiple signaling events simultaneously in specific cell types within mixed populations. The objective of this study is to design a sensitive and high-throughput assay to measure key points of regulation in the insulin signaling pathway for myocytes using flow cytometry. We have developed a multicolor flow cytometry panel to measure the insulin stimulated phosphorylation of Akt(S473) and the transport of the insulin responsive glucose transporter, GLUT4, to the plasma membrane. C2C12 myoblasts were stained with primary conjugated antibodies for pAkt(S473) and an extracellular region of GLUT4, indicative of translocated GLUT4 present
in the plasma membrane. Both C2C12 myoblasts, an immortalized cell line, and primary myoblasts, isolated from non-human primate muscle, responded to insulin with increased pAkt(S473) and plasma membrane GLUT4 with an EC50 of <10nM, similar to physiological response. Future work will expand the panel to measure phosphorylation of insulin receptor substrate and phosphoinosital 3-kinase (PI3K) activity by quantitating phosphoinosital (3,4,5) phosphate (PIP3) production. The sensitivity of the assay will be demonstrated by inhibiting key insulin-activated kinases including PI3K by Wortmannin, and Akt activation by MK- 2206 and measuring insulin signaling at points up and downstream of inhibition. We anticipate that this will provide a powerful method to rapidly dissect the insulin signaling cascade for a specific cell type within mixed populations of cells.

Influence of Sensory Systems on Social Behavior

Presenter(s): Adeline Fecker

Faculty Mentor(s): Phil Washbourne & Sarah Stednitz

Poster 75

Session: Sciences

Disruption in social behavior is characteristic of Autism Spectrum Disorder, which is a neurodevelopmental disorder that appears in early childhood. Previous papers measured social orienting behavior in zebrafish in a dyad assay and showed lesioning of the ventral forebrain reduced social orienting specifically (Stednitz, 2018). These specific neurons may be evolutionarily conserved and may be found in humans. This study aims to identify other parts of the forebrain that may be implicated in social behavior, to understand which senses contribute to social behavior, and to understand how brain activity patterns relate to sensory conditions and behavior. Measuring behavior in an open field allows us to qualify more complex social behavior like orienting, following and dispersing. The Stednitz (2018) paper suggested subjects must be able to see each other to demonstrate orienting behavior and show activation of the ventral forebrain. However, in an open field, subjects are able to interact without visual stimulus. A deeper investigation into the importance of sensory systems in social behavior can be achieved through olfactory and mechanosensory ablation. Early results suggest the visual system is not required for social interaction, as zebrafish can still follow each other in the dark. Whole brain immunolabeling with pERK and ERK allows for an unbiased approach to identifying important brain regions in social orienting. The neurons in the ventral forebrain (marked “ y321 ” with GFP) acts as our landmark, and our results confirm the importance of the ventral forebrain in social behavior. However, other regions of the forebrain vary in activity in different experimental sensory conditions. Our analysis of behavior and corresponding brain activity will shed light onto more regions that may be implicated in social behavior.