Oral Presentations - Session 2F: UC 333
|Friday, April 12th|
Cholinergic neuromodulation of parvalbumin interneurons during hippocampal gamma oscillations and pilocarpine-induced seizures
Evan DeCan, University of Montana - Missoula
1:40 PM - 2:00 PM
Epilepsy, one of the most common neurological diseases, is widely studied in the medical and scientific fields. The pilocarpine model of induced epilepsy has become a standard for studying seizures in a laboratory setting, allowing further investigation into specific mechanisms underlying seizure activity. Parvalbumin-positive (PV+) interneurons, a specialized class of inhibitory cells, are implicated in pilocarpine-induced seizures. However, the underlying mechanisms by which PV+ cells contribute to seizure generation are unknown.
The precise balance of the inhibitory and excitatory neuronal networks is critical to normal brain function. Imbalances between inhibitory PV+ cells and excitatory glutamatergic networks could contribute to seizure generation and other pathological states. Here, we test the hypothesis that pilocarpine, a nonselective muscarinic receptor agonist, activates PV+ interneurons and renders hippocampal circuits vulnerable to seizures. Our laboratory has previously demonstrated that the elimination of M1 muscarinic acetylcholine receptors (mAChRs) from PV+ cells results in a loss of cholinergic modulation of PV+ cells, learning deficits, and seizure protection. .Using pilocarpine application to hippocampal slices, I will determine whether pilocarpine activates PV+ cells through glutamatergic circuits or by direct excitation of M1 mAChRs on PV+ cells. These studies will lead to a more comprehensive understanding of the processes underlying epileptiform activity.
The Affect of Altered Exercise Intensity on Postural Stability
Claire Nickless, University of Montana - Missoula
2:00 PM - 2:20 PM
PURPOSE: To determine if the center of balance was affected by the administration of bouts of exercise performed at different intensities. Our secondary aim was to determine how long it took for balance to return to baseline assessment values, following cessation of exercise. METHODS: 16 male subjects (25±5yrs, 183±10cm, 73±11kg, 4.4±.73 LO2?/min) volunteered and provided their informed written consent for the study. Participants were free of balance disorders and recent history of concussion. Subjects visited the lab twice and performed exercise at 40, 60, 80, 100, and 120% of the level necessary to elicit a maximal response from the body’s respiratory and circulatory systems. Following each bout of exercise, balance scores were assessed every 5 minutes for 30 minutes from a portable force plate in four conditions: normal stability eyes open (NSEO), normal stability eyes closed (NSEC), perturbed stability eyes open (PESO), and perturbed stability eyes closed (PSEC). Perturbed stability required subjects to stand on a foam mat placed on the fore plate. RESULTS: Two-way anova indicated that following 120% intensity there was a significant decrease in NSEO from baseline. Stability scores returned to baseline after ten minutes. Our findings suggest a similar impaired stability following exercise at 80% intensity. CONCLUSIONS: Our results showed that immediately after exercising at 120% intensity there was a decrease in stability score compared to baseline. We conclude that balance is impaired for at least 10 minutes following vigorous exercise. These assessments and findings should be incorporated into sideline testing procedures used for the diagnosis of concussion in sport.
Get Fit for Sport: Year Around Fitness Programs for Intellectually Disabled Individuals
Andrea Flippin, University of Montana - Missoula
2:20 PM - 2:40 PM
The intellectually disabled population has increasing rates of obese and overweight individuals. Special Olympics, an organization designed to support recreational and Olympic type sporting events for this population, has brought focus to the issue by encouraging integration of fitness and healthy living into their lives. These athletes are physically active during their selected sports season, but it is reported they are not meeting their daily recommended amount of activity during the off season. The aim of the "Get Fit for Sport" program was to categorize Special Olympian physical fitness and develop year-round personalize training programs. The plan of providing year-round programs to each athlete was to encourage them to complete their daily activity requirements in the off season as well as additional light activity when they are in season. Four subjects were tested on aerobic activity, flexibility, strength, and balance to determine current physical capabilities. The test data were used to categorize the subjects as weak, moderate or strong in the four tested areas. Included in our results was a personalized survey conducted by the testers to understand the subjects’ preference of exercise, intellectual ability, and accessibility of equipment. Data collected from the tests and surveys were used to create personalized fitness plans for each subject. Within these plans each athlete was given an example week that they could incorporate into their lives. During the week all four categories are focused on, aerobic activity examples, strength training exercises, stretches for flexibility, and exercises to improve balance. Giving the athletes a well-rounded program for life long fitness.
Comparing the Effects of Moist Heat Pack and Pulsed Short Wave Diathermy on Shoulder Range of Motion
Taylor C. Baldwin, University of Montana - Missoula
2:40 PM - 3:00 PM
Thermotherapy has been used within the scope of athletic therapy for its beneficial therapeutic effects. Superficial thermotherapy is an inexpensive, easy way to heat local tissues at depths less than 2 cm; whereas, deep thermotherapy is more expensive and less traditional way to heat, but penetrates to deeper structures. This study compares the effectiveness of moist heat packs and diathermy on shoulder range of motion. To date, there is no research comparing these two modalities ability to improve shoulder range of motion. The purpose of this study was to see if there is a significant difference in using a moist heat pack or pulsed short wave diathermy to improve shoulder range of motion. Six athletic training students enrolled in the University of Montana Athletic Training Education Program were used in this study (3 males, 3 females). Their ages range from 20-25 with a mean age of 22 years ± 1.79. The mean height of the participants was 68.92 inches ± 2.34 with a mean weight of 166.5 lbs ± 29.15. All participants had no previous history of shoulder injury in either shoulder. A SPI TRONIC Digital Inclinometer was used to measure shoulder internal, external rotation, and horizontal adduction. Three measurements were taken before and after a 20 minute moist heat pack, diathermy, or control treatment. The participants completed each treatment once with at least 48 hours between treatments. Our results indicate that the use of modalities independently has minimal effects on shoulder range of motion. Therefore, in conjunction with current research, clinicians should use these modalities in conjunction with exercise to maximize benefits. Further research is necessary to determine if the use of hot packs or diathermy in combination with stretching routines or shoulder strengthening exercises may have a greater impact on shoulder range of motion than exercise alone.
The Effects of Single Point Mutagenesis in the SSP Subunit of the Junin Virus Envelope Glyco-protein on Membrane Fusion
Donna Twedt, University of Montana - Missoula
3:00 PM - 3:20 PM
Arenaviruses are RNA-based viruses commonly found in rodents, and can cause severe hemorrhagic fever in humans, often resulting in death. In order to infect, the virus must enter the host cell by fusing its membrane with that of the cells. The viral envelope glycoprotein (GPC) which retains its stable signal peptide is necessary for this fusion activity to occur. For my studies, I wanted to understand how the three GPC subunits (SSP, G1, and G2) work together by looking specifically at how the stable signal peptide (SSP) subunit interacts with G2. This can be done by examining how they interact in the membrane because the G2 subunit spans the membrane and is thus in a position to interact with the membrane region of SSP. Cysteine-scanning mutagenesis was conducted to replace three important polar residues on the hydrophilic face of the membrane-spanning region of SSP (T13C, E17C, and N20C) with cysteine. Cells expressing GPC were then metabolically labeled with radioactive amino acids and GPC was immunoprecipitated. This method is generally referred to as a radioactive immunoprecipitation and was conducted to determine if the mutations affected cleavage of the G1G2 precursor or SSP association with the G2 subunit. The immunoprecipitations showed that cleavage and SSP association did in fact occur. I then wanted to know if the mutants supported fusion and thus performed a cell-cell fusion assay. The results indicate that fusion did occur in all of the mutants. These results suggest that the mutant SSPs are functional, and further studies are being pursued to crosslink the cysteine mutations introduced in SSP with cysteine mutations in G2 to determine how the subunits interact in the GPC complex.
The Struggles of International Research in a Developing Country: A Study on Diabetes Prevalence Rates in the Rural Arumeru District of Tanzania
Tyler Ellis, University of Montana - Missoula
3:20 PM - 3:40 PM
International research is plagued with various struggles, the main being obtaining permissions to conduct such research. Permissions from people such as an Ethics Review Committee along with governmental clearance are required to proceed. Upon leaving the boarders of the United States of America, a researcher must not only obtain these permissions, but also respect the local requirements of the country that the research project is being conducted in. Once permission is obtained, the fate of the research project is ultimately left up to the discretion of the host. Selection of a host is vital, for they are ultimately responsible for facilitating the travel as well as providing participants to conduct a study on. The host can also make obtaining previously discussed permissions easier through locally acceptable routes. The next struggle is the language barrier and obtaining competent translators to work to conquer this barrier. Developing countries have limited resources and supplies. Once the researcher runs out of materials, he/she is usually finished. One has to plan ahead to obtain needed materials before starting the project. Some scientific methods, such as true randomization, are not possible due to inability to travel to desired locations. The ability to see the overall project and alter the experiment's protocol to adapt to the conditions provided by the hose is rarely encountered in research within the United States of America. An international researcher needs to be able to think rapidly and adapt to create a successful project while keeping the variables limited; no matter what struggles present themselves. This novel methodology outlines basic struggles on how to conduct and adapt to the struggles of international research in a developing country. This is done utilizing a case study on the prevalence rates of diabetes and pre-diabetes in rural villages of the Arumeru District of Tanzanian.