Tag Archives: motor

Why are frogs able to survive in low oxygen conditions?
Bianca Okhaifor
2020, senior, biology major/chemistry minor
University of North Carolina at Greensboro

My Research Project

Credit: Drew R. Davis, Amphibians and Reptiles of South Dakota

Most living organisms rely heavily on oxygen (O2), a major component in an organism’s biochemical and metabolic functions. This isespecially important for the brain. When the brain is deprived of O2), injury and life-threatening situations can occur. We can learn a great deal from a neural system that has evolved to combat hypoxia (low oxygen levels) and anoxia (no oxygen) in the brain. During my summer research project, I focused on the Lithobates catesbeianus, most commonly known as the American bullfrog.

Though respiratory network activity ceases during severe hypoxia, the network is able to generate again upon reintroduction of O2 and return to its normal functions (Winmill RE, et al). How is this possible? By building upon background information, we hypothesized that inhibition of ATP synthesis through different routes in the presence of oxygen would resemble the anoxic response if metabolic failure contributes to the network shutdown. To test this hypothesis, I focused on the bullfrog’s cranial nerves and used them to record electrical brain activity. Depending on which part of the experiment I completed each day, a certain drug was administered to the brainstem to analyze its effects. Our findings showed that neurons in the frog brain can survive without ATP synthesis for extended periods of time with no impact on function after reoxygenation, suggesting that metabolism is an important contributor to allowing bullfrogs to survive anoxia.

Realities of Research

Artificial brain fluid on magnetic stirrer, Dr. Joseph Santin lab, UNC Greensboro

Research is one of the most important aspects of human advancement and development. Unsurprisingly, scientists have great responsibilities that pose many challenges. One of the biggest challenges of a scientist is the reality that research is unpredictable. Although my lab’s results generally supported my hypothesis, there were days when experiments did not work and I had to backtrack, figure out my mistakes and start over. Unpredictable results can also mean that your day is too unpredictable. I had to take initiative for what needed to be done and be responsible enough to make it happen. It surprised me that I wasn’t told what I needed to do every day, minute by minute. I had to take charge of my project. This is especially true for scientists who may be doing novel research or research not found in the available literature. While this aspect of research is challenging, it is also fun to brainstorm the best way to go about your research. For instance, I had to categorize and analyze the data collected of neuronal motor output of the bullfrogs.; This had not been done before and Ihad to learn analysis techniques as well as use my creativity and knowledge to create a system of categorization. Being able to highlight my passion for problem solving and creativity was what kept me so interested in research.

Life as a Scientist

White coats, colorful chemicals and a crazy, wild lab. This “Hollywood stereotype” may be what comes to mind for some people when they think about a scientist. As a first-generation minority, that’s what came to my mind as well. I had not been exposed to research as a career and only knew what I saw in the media. It was not until I received the 2019 Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) fellowship that I was able to understand the life of a scientist—and it was drastically different from what I expected.

In my experience, there is no “day-to-day life” of a scientist. Every day was different. One day I may have dissected a brain from a frog, while the next, I analyzed data and the day after, I was expanding my knowledge further by reading scientific literature. Some days, I had lots of hands-on work and was really busy and other days, I had plenty of downtime. While this dynamic work environment was fun and exciting, it was also very challenging for me. I was fortunate enough, and will be forever grateful, for being placed within a lab team that helped me work through my hesitations this summer. My team consisted of another undergraduate student, a masters student and my principal investigator. Having these three people in my circle allowed me to transcend the expectations I had for myself. I hope that I can one day use this experience to expose young, first-generation minorities to what it means to be a scientist early in their careers. This is a tool I wish I had when I was younger.

Reference:

Winmill RE, et al. “Development of the Respiratory Response to Hypoxia in the Isolated Brainstem of the Bullfrog Rana Catesbeiana.” The Journal of Experimental Biology, vol. 208, 2005, pp. 213–22

Bianca Okhaifor is a senior at the University of North Carolina at Greensboro. She is a 2019 Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) Fellow working in Dr. Joseph Santin’s lab at the University of North Carolina at Greensboro. Bianca’s fellowship is funded by the APS and a grant from the National Heart, Lung and Blood Institute (Grant #1 R25 HL115473-01). After graduation, Bianca plans to pursue a career as a physician and clinical researcher to focusing on her passion of working specifically with minority children with little to no access to healthcare.

A Summer Study: Respiratory Rehabilitation After Spinal Cord Injury
Amari Thomas
Senior, Biology
University of Florida
2019 STRIDE Fellow

My Research Project

The human body central nervous system.

Because the central nervous system is in control of every process taking place within the body, an injury to this system can be detrimental and sometimes fatal. Injuries to the cervical region of our spinal cord can be extremely difficult because they often lead to breathing impairment. The phrenic motor nucleus in this region innervates our diaphragm, which controls inhalation by creating a negative pressure ventilation system.

It has been shown that acute intermittent levels of low oxygen help to address the concern for the functional recovery of breathing after injury. This occurs because the phrenic motor nucleus elicits neuroplasticity. A key protein, phosphorylated-ERK (p-ERK), is involved mechanistically in the phrenic motor nuclei response to varying levels of low oxygen.

P-ERK’s expression can be analyzed through epifluorescent microscopy. The cervical spinal cord tissues were harvested from rodents and stained using inmunoflouresence, – a procedure that stains the tissues in a way that allows them to emit certain colors when viewed on a microscope. We injected cholera toxin B between the pleural cavity in the outer layers of the rodents’ lungs before injury, which allowed for selective localization of phrenic neurons. We imaged this tissue to assess different expression patterns of p-ERK after spinal injury and varying levels of intermittent hypoxia.

Once we analyzed the expression of p-ERK in phrenic motor neurons after spinal injury and intermittent hypoxia we were able to develop a better understanding of intermittent hypoxia and its elicited plasticity after spinal injury. This research will guide therapeutic strategies for improving breathing in people with spinal injury.

Life as a Scientist

Using rat models as a method for testing before human clinical trials.

My experience as a scientist this summer opened my eyes to the realities that occur behind the scenes of groundbreaking research. For example, I always believed clinical trials to be amazing advancements in research, but never truly understood all of the experiments that take place before humans are even brought into the picture. The work done in our lab on rats propose a model for human experimentation. This opportunity has also made me realize that things may not always go exactly as planned the first time around and that is perfectly okay. Often, these trials and errors allow us to learn more about the research we are doing in order to propose different hypotheses or use alternate methods. There is no right or wrong when it comes to research because it is a learning and growing experience.

Acknowledgements

Elisa Gonzalez-Rothi, DPT, PhD, Research Assistant Professor, University of Florida Department of Physical Therapy

Gordon S. Mitchell, PhD, Professor of Physical Therapy, University of Florida Department of Physical Therapy

Latoya Allen, PhD, University of Florida Department of Neuroscience

Marissa Ciesla, PhD, University of Florida Department of Neuroscience

Amari Thomas is a first-generation college student majoring in biology at the University of Florida in Gainesville. She was born and raised in Miami Gardens, Florida, where access to research labs and quality educational resources are minimal. Due to her academic success in grade-school and extracurricular involvement, Amari was accepted into one of the top universities in the country for her undergraduate education. She has continued to thrive in her undergraduate career by gaining dean’s list awards for academics, mentorship positions and an outstanding fellowship from the American Physiological Society. By working in a research lab, Amari has expanded her career options and strengthened her knowledge of the human body and its many processes. She hopes to obtain a medical license after graduating and plans to apply the knowledge learned in the research lab. Amari is a 2019 Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) Fellow in the lab of Dr. Elisa Gonzalez-Rothi at the University of Florida in Gainesville. Amari’s fellowship is funded by the National Heart, Lung and Blood Institute (NHLBI; R25 HL115473-01).

Hypertension Prevention: does it also improve motor cognitive function?

Research Project

This summer, I’m studying the effects of inspiratory muscle strength training on motor and cognitive function in middle-aged to older adults. Motor function is the ability to move the muscles in your body, and cognitive function is your brain’s ability to perform tasks. Inspiratory muscle strength training, or IMST, is a relatively understudied technique of exercising the muscles you use to breathe in. By breathing in, or inspiring, against a resistance with a small device that looks similar to an inhaler, you can make these muscles stronger and hopefully improve many bodily and cellular functions, including motor-cognitive function. What is currently known about IMST is that it can significantly improve blood pressure in healthy adults (DeLucia, De Asis and Bailey, 2018), but its effects on adults with high blood pressure have not been tested yet. The IMST study on the large scale is focusing on the possible blood pressure and cardiovascular benefits of IMST in adults with high blood pressure, and I’m focusing my research and data analysis specifically on the motor cognitive functions that we also test.

Because a decline in motor-cognitive (shortened to motor-cog) function is highly correlated to mortality (death) risk, there is a large scientific effort to evaluate the effectiveness of various forms of intervention to improve these variables. Motor-cognitive decline is characterized by dementia and immobility, which are not only independent predictors of mortality risk, but large influential factors on perceived quality of life for older adults. It is well established that a consistent aerobic exercise routine will effectively prevent motor-cognitive decline in older adults, but because of its heavy burden, it is not frequently adhered to. Finding other effective practices of improving motor and cognitive function that are more adherable will greatly improve the quality of life for aging individuals and lower their mortality risk.

Realities of Research

Figure 1: Formaldehyde used for preserving endothelial cells

So far, I have found that doing clinical research in a lab is full of excitement and surprises! Beginning at the start of the fellowship, clinical interactions and the IMST study became only two of my many responsibilities. I have been trained on wet lab procedures such as cell collection and isolation, as well as blood processing to assess certain chemicals in the blood. These tasks can be tedious, and are very time and method sensitive. I can spend two hours doing the cell collection and isolation for them to later not give any helpful results when I analyze them. Experiencing frustrating aspects like this is helping me develop the very important skill of patience. I have to use patience in many aspects of my work; wet lab mishaps are not the only issues one can encounter during a typical day of research. I am working in one of the most dynamic physiology labs in the country, with some of the brightest in the field, but despite this we all run into our fair share of hiccups. For example, our huge datasheet for our study got deleted and we spent several days trying to find it. Also, our freezer logging software crashed and left us without decades of logged biological sample information!

Figure 2: Freezing plasma in liquid nitrogen for later analysis

 

 

On the other side of my work, I have to use patience with the clinical subjects. When working with more stubborn older subjects, I find it’s essential to remain patient to maintain professionalism, and to represent our lab in the most positive way possible. I’ve had difficult interpersonal interactions with some of the subjects, but remaining patient and working through issues and questions with them upholds the highest standards of human research we have as an institution. Anyways, our IMST study has (despite some problems) been very on-track and is moving along at a quick pace. We just received more funding from the NIH through a grant that will support us through the next two years of research. Woohoo!

Life of a Scientist

Living as a scientist this summer has been a truly rewarding and educational experience. Going from a very part-time volunteer in the lab doing data entry, to a full-time member of the lab team with much more responsibilities has been an eye-opening transition. I am a much more integral part of the team, and I have to be much more accountable than I was before. I went from only having one task to focus on at a time, to having three-four or more, including clinical visits, grant reviewing, abstract writing, journal club presentations, and reading physiology literature. Balancing and prioritizing my lab tasks is difficult and stressful, and has shown me the less-glamorous side of basic research that you don’t realize until you experience it for yourself. On the other hand, I have been supported in so many ways I never expected, and I love working in a team-based environment. As a non-traditional community college student, I always felt like an outsider and thought I would never be fully accepted into the scientific/academic world. I was proven wrong. Our lab has endless support and an open-door policy when it comes to questions and concerns, which encourages communication. Every member of my lab team has been so helpful in educating me in physiology and research topics I’m unfamiliar with, and has given me all the opportunities I could ask for to be successful at this early stage of my research career. In fact, I should have at least two publications by the end of next year, and probably three by the time I finish my undergraduate studies. This amazing experience has strongly encouraged me to further pursue my career in physiological research.

 

Sources:

DeLucia, C., De Asis, R. and Bailey, E. (2018). Daily inspiratory muscle training lowers blood pressure and vascular resistance in healthy men and women. Experimental Physiology, 103(2), pp.201-211.

Makinzie Hamilton is an undergraduate junior studying Integrative Physiology and Philosophy at the University of Colorado, Boulder. She is working at UCB under Dr. Douglas Seals at the Integrative Physiology of Aging Laboratory, which focuses on improving cardiovascular aging. She is funded through grants from the STRIDE fellowship from the APS and The National Heart and Lung Association (Grant #1 R25 HL115473-01). After graduating in 2020, she hopes to pursue a dual MD/PhD degree and do clinical research regarding infectious disease and tropical medicine. In her free time, she enjoys studying true crime, cooking, painting, and fishing.