Department: Scholars

Hi, my name is Sandra Mendiola. I grew up in Hemingford, Nebraska, and attended Yale University in New Haven, Connecticut, where I graduated with a degree in Ecology and Evolutionary Biology.

I first became interested in science after I spent the summer after high school graduation working as a lab technician for the Potato Certification Association of Nebraska (PCAN). As part of PCAN, I collected, identified, and screened potato psyllids for Candidatus Liberibacter solanacearum, the bacterium responsible for zebra chip disease in potatoes. Working at PCAN was a catalytic experience for me. Not only did it allow me to explore the world of laboratory science, but it also introduced me to one of my major research interests, the dynamics of vector-borne disease.

Throughout my time at Yale, I became increasingly interested in questions at the intersection of the ecology, epidemiology, and evolution of infectious disease. Although I was able to explore these interests both in the classroom and at the bench, my undergraduate education barely scratched the surface of what I wanted to know.

It was clear that the only way to answer the higher order research questions I was interested in was to pursue a PhD.

However, because I was intrigued by various disciplines, I felt I needed more time to reflect on my research interests before applying to graduate school. PREP@UGA was an ideal program for me to explore my interdisciplinary interest in infectious disease. During my time here, I hope to grow as an independent researcher and enhance my science communication skills in preparation for graduate study and for an eventual career in academic or government research.

At UGA I am working with Dr. David Stallknecht and Dr. Mark Ruder with the Southeastern Cooperative Wildlife Disease Study which is part of the Department of Population Health in the College of Veterinary Medicine. My project is focused on epizootic hemorrhagic disease (EHD), an acute and often fatal viral illness in white tailed deer. EHD is vectored by biting midges of the genus Culicoides.

It is known that EHD infection leads to long-term viremia in deer, however, the amount of time viremic deer remain infectious to midges has yet to be characterized. My project seeks to elucidate temporal variation in host infectivity as measured by infection rates in Culicoides sonorensis, a major vector of EHD in North America. To do this, I will use both traditional virology and PCR techniques to isolate and titrate EHD virus from midges that were fed on experimentally infected deer over the course of viremia. Data obtained from this experiment will help determine the time frame during which midges are most likely to acquire EHD from infected deer and serve as potential vectors. This knowledge will further optimize disease models of EHD by accounting for differences in host infectiousness throughout viremia.

My name is Sandra Mendiola, and I’m a PREP@UGA scholar.

Hi, my name is Belen Molina.

I attended college in my hometown at the University of Arizona, where I graduated with a degree in Ecology & Evolutionary biology with a second major in Molecular & Cellular biology. My journey toward becoming a young scientist started off on an unpredictable path. As a first generation undergraduate student I found myself disoriented and without guidance. During this time I met a wonderful Argentinian woman who would undoubtedly change my life. Her name is Dr. Patricia Stock.

She welcomed me into her lab where I learned how to critically think about my surroundings, ask interesting and important questions and challenge myself to try to find answers. I also found myself captivated by the diversity in her lab. For the very first time during my college career I was working with diverse individuals; people who I feel I can relate to. My peers and mentors shared stories of how they overcame hurdles as minorities to become successful scientists. I realized then that science has no borders and that through science many could have a voice; a progressive impact on others. I knew from that moment on that I wanted to strive to pursue a Ph.D. in science while also contributing my passion to the public.

My excitement for science and community sparked my interest is in microbiology and science policy. I am intrigued by host-pathogen interactions but also find myself passionate about policy and change around the world.

My long term goals are to obtain a PH.D. in microbiology where I can study host-pathogen interactions in neglected diseases. I hope to use this knowledge to become involved in science policy and implement better strategies regarding these diseases in destitute countries, like Latin America.

I decided to join PREP because I wanted to be better equipped for a graduate school. I wanted the guidance and preparation I need to be successful in obtaining my Ph.D. The program has enriched my path toward a doctorate degree and has benefited me professionally. My hope is to hone the skills necessary for answering meaningful questions and also to gain the professional development needed to engage in a collaborative science community.

This year I have the honor of working with a brilliant disease ecologist, Dr. Vanessa Ezenwa, on a project involving a very interesting mouse with regenerative properties in adulthood called the spiny mouse. This mouse is originally from Kenya Africa and in addition to its awesome ability of growing back tissue the mouse also has a high bacteria killing capacity. Previous studies have narrowed down this characteristic to the humoral immune system but the specific element that is contributing the high elimination of bacteria remains a mystery. Preliminary results have already ruled out component proteins as a contributor and it is now my job to find out if lysozymes are at the root of this phenomenon.

My goal in the Ezenwa lab is to find out if the pattern of lysozyme content in the spiny mice match the pattern seen in bacteria killing assays and thus contributes to the high bacteria killing capacity. To test this question I first have to optimize a tubidimetric assay for the use in wild rodents. The assay essentially measures the loss of intensity of transmitted light of a known wavelength due to the particles suspended in it. A measurement is then given for the amount of absorbed light and can be used to find the number of cells in a solution. Once the assay is optimized I can use the data to best interpret if lysozymes are causing this mouse to be especially good at killing bacteria.

This project will allow me to develop skills in experiment design and troubleshooting, as well as, hone molecular techniques like measuring cell counts and monitoring proteins of interest.

My name is Belen Molina and I am a PREP@UGA scholar.

Hi, my name is Jose Luiz Rodriguez. I grew up in Long Beach, California and attended North Greenville University in Tigerville, South Carolina and graduated with a Bachelors of Science in Interdisciplinary Studies. I became interested in the field of science around my junior year in high school. My teachers for chemistry and biology showed me a world that internally motivated me to pursue my new found interest in science.

Once accepted to North Greenville University, my interest towards research was nurtured and developed by the countless professors who dedicated time and knowledge to my time as a student. In particular, one professor, Dr. Dodson, showed me the countless possibilities of research focuses through her courses of Biochemistry, Parasitology, and Advanced Metabolism.

As for my research interests, I am interested in infectious diseases and proteins related to host invasion. Ultimately, my goal as a researcher would be to operate my own clinic and laboratory in cutting edge research for infectious diseases that are poorly funded. In order for me to reach my long term goal, I decided to join PREP@UGA because it was the best path to prepare my future as a graduate student in a top research institute. Prep@UGA is the best program for me due to its focus on the scholars success not only as current post-baccalaureate students, but also in all aspects of professionalism, research, and life as scientist. (As a PREP scholar, I hope and plan to advance my knowledge and skills in all areas of lab research, but also to mature as a scientist in professionalism and conduct.)

During my time at PREP, I will be under the mentorship of Heather Bishop, a fourth year PhD candidate, and my faculty mentor, Dr. Vasant Muralidharan. In our lab we study the deadly malaria parasite, Plasmodium falciparum. This parasite is responsible for almost a million death cases a year, most of them in children and pregnant women in sub-Saharan Africa. It is a eukaryotic pathogen with a complex life cycle, unknown function that is named GRP170, after its yeast homolog. Despite the challenging genetics of P. falciparum, we took a conditional knockdown approach and inhibit the activity of GRP170 in order to study its biological roles under physiological settings. We found that GRP170 inhibition results in parasite death, indicating that it is essential for parasite viability. We also found that upon GRP170 inhibition, the parasite becomes more sensitive to high temperatures, suggesting that GRP170 is involved in heat shock response. Moreover, gameto-cytogenesis was found to be impaired in the mutants, suggesting that it is involved in sexual development.

We are currently designing tools that will enable us to identify potential molecular partners of GRP170. We hope that this project will shed light on the complex mechanisms of protein trafficking in P.falciparum and will help us not only to better understand the biology of this parasite, but also potentially identify new drug targets.

My name is Jose Rodriguez and I am a PREP@UGA scholar.

Hi, my name is Nathalie Carla Thezan. I grew up in Miami, Florida and went to college at Long Island University in Brooklyn, New York and graduated with a Bachelor’s of Science degree in Biology.

I first became interested in science while volunteering in Port au Prince, Haiti. I participated in numerous medical missions, but the experience that stood out to me the most was when I witnessed the process of rapid HIV tests. I was astonished by how simply adding the combination of a blood sample and latex reagent to an immunoconcentrated cassette can instantly detect a life-threatening virus. Further investigation led to basic comprehension of the assay of rapid HIV tests, but I wasn’t satisfied; I was still craving to understand the proper science behind it.

I decided on a career in research because I am predominately interested in making a broader impact on the elucidation of infectious disease mechanisms in context of pathogenesis.

I am mostly interested in the association of microbiology, infectious diseases, and public health.

My long-term career goals are utilizing knowledge from my doctoral studies to continue performing research in a governmental or industrial setting. In addition, I plan to construct a non-profit laboratory in Port au Prince, Haiti, where scientists can collaborate and study maladies that affect the native population.

I decided to join the PREP program to fortify my research experience, which will contribute to making me a top candidate as I apply to competitive and prestigious doctoral graduate programs. Being a PREP Scholar has further confirmed that I belong in research.

My faculty mentor is Dr. Vincent Starai and my research mentor is Emily Carpinone. In Dr. Starai’s lab, we identify and biochemically characterize secreted proteins from intracellular bacterial pathogens that are capable of modulating host membrane dynamics. Bacteria from the genus Wolbachia, are considered one of the world’s most common parasitic microbes, as they can survive within the cells of a diverse number of invertebrate species. While it is unknown how Wolbachia persists within its host, it likely uses a set of secreted proteins to ensure its intracellular survival. Using a simple yeast model system to mimic a eukaryotic host cell, we have obtained preliminary data that demonstrates one such protein, called wBm0152, has the ability to alter the normal trafficking of endosomal cargo. My independent project focuses on identifying the molecular targets of wBm0152 in yeast, which are likely conserved in Wolbachia’s nematode host. I hypothesize that Wbm0152 alters eukaryotic membrane traffic in order to ensure Wolbachia endosymbionts persist and disseminate in its natural host. To address my hypothesis, I will use a varied research approach including yeast DNA transformations, florescence microscopy, PCR, and Western blotting. Identification of these molecular targets will provide new information regarding the ability of Wolbachia to alter host physiology.

My name is Nathalie Carla Thezan, and I am a PREP at UGA Scholar.

Hi, my name is Troy Michael King Jr. I was born in New Orleans, Louisiana and raised in Powder Springs, Georgia. I went to college at Oklahoma State University in Stillwater, Oklahoma and graduated with a Dual Degree in Biochemistry and Microbiology in the Spring of 2016.

My interest in science began as early as elementary school but more particularly during my 12^th grade Biology class where my teacher presented science as a fascinating prospect filled with vast mysteries within our genetic code and the organisms we interacted with.

During my first year at Oklahoma State, I wanted more exposure to science. While researching careers, I found that upper-tier careers in science required an education beyond a bachelor’s. From my ambition to conduct research, I was allotted my first opportunity by a graduate student when I expressed interest in aiding him with his project. This experience further rooted my admiration of science and I continued to grow and evolve over my additional research opportunities.

My current interests involve the study of host-pathogen interactions. I am particularly interested in understanding the mechanisms pathogens possess to evade host immune responses and develop infection.

When looking at long-term prospects, I envision myself as a research professor at an institution where I can mentor students to pursue higher education. Research, to me, is an outlet for my creativity and wonder. A research professor possesses responsibility and integrity in their lab and towards students in their classroom and I plan to become a role model that possesses a fire in my teaching to incite my passion towards others.

I joined PREP because I wanted an opportunity to conduct research in an infectious disease lab where I can explore host-pathogen interactions. Additionally, I wanted to obtain additional laboratory and critical thinking skills that would prepare me for future graduate studies.

PREP@UGA has been a program that focuses on my desire to grow in my writing and oral communication. I love PREP@UGA’s connection with the department of Infectious Diseases because this is the field that most fascinates me. Through PREP@UGA, I have resources such as an Individual Development Plan and presentation feedback forms which aligns with my goal to become further adept in science and achieve my goal to be a principal investigator.

There are several elements I plan to receive from my time in PREP@UGA. First, I hope to increase my scientific literacy to be able to express my ideas to a broad range of individuals. Second, I plan to build a strong foundation for becoming a disciplined and passionate scientist so that I can motivate others to consider a career in an exciting field of science. Lastly, I want to increase my confidence to be an independent component of a lab to be able to form ideas from my experiments that exhibit advancement in the field.

My faculty mentor is Dr. Eric Harvill, and two of his postdocs, Dr. Holly Vuong and Dr. Illiasou Hamidou Soumana, are my research mentors. Together we are addressing questions on the interactions of pathogens and commensal bacteria.

My project is to understand the role of the respiratory microbiota in protecting the host against an invading pathogen. We have two Bordetella species that produce very different results in how they interact with the host microbiota, even though they are genetically very closely related to each other. Bordetella bronchiseptica and Bordetella pertussis. Dr. Harvill’s lab has shown that while B. pertussis, the human pathogen, cannot easily invade into a mouse unless the mouse was given high amounts of the pathogen, B. bronchiseptica very easily infects mice with very low amounts. It appears that B. bronchiseptica can disrupt the nasal microbiota and occupy the nasal cavity, and still be the primary culturable bacteria even after 70 days of the initial infection! I hypothesize that host specificity by Bordetella species can affect their disruption ability and colonization rates in hosts. Because we have such a good mouse model with this, my work will focus on how B. bronchiseptica displaces the nasal microbiota. But to get to the larger picture first, we need to carry out simple, clearly defined competitive experiments in culture to study their interactions and understand the mechanisms behind the disruption before we can move to the actual mouse host

My approach to answering this question involves breaking down the composition of the mouse nasal cavity using 16S rRNA sequencing to identify potential candidates for interaction with Bronchiseptica. I will identify the specific conditions to study clearing in culture. I will also strengthen the growth assay to determine important genes for this clearing mechanism by using mutant RB50 strains that lacks the clearing mechanism mice. In order to further test implications of pertussis clearing of human microbiota, I will manipulate mouse microbiota to acquire the appropriate conditions to test pertussis colonization strategy.

The Harvill Lab has been supportive in helping me develop and expand upon my ideas and the collaborative setting is crucial for my development.

My name is Troy M. King Jr. and I am a PREP@UGA scholar.

Hi, my name is Cybelle Tabilas. I grew up in Woodland, California and I graduated with a Bachelor of Arts in Biology from Willamette University in Salem, Oregon.

I first became interested in science as a young child through television specials and series. In an episode of The Magic School Bus called Inside Ralphie, Ms. Frizzle and the class try to figure out what Ralphie is sick with and this sparked my interest in human illness. By watching shows like this, I was introduced to a world that I could not see or control and this is when I decided I wanted to understand the mechanisms that drive the world.

For me, a career in research means standing between the line of knowledge and the unknown and having the tools, power, and creativity to decide how you want to cross that barrier.

The research area I am most interested in is immunology.

I am still unsure of what my ultimate career goals would be. I would love to do research for a government institute like the CDC or NIH to address public health issues in infectious diseases, but I am also interested in becoming a professor and mentoring the next generation of scientists at a liberal arts college similar to the one I graduated from.

I always knew I wanted to take a gap year between my undergraduate education and graduate school. When I learned about PREP, it sounded like the perfect mixture of what I imagined my gap year to be. It would allow me to experience and understand what life as a first
year graduate student would entail while doing an intensive and independent yearlong project in a subject I was interested in.

I chose to become part of PREP@UGA because of the diversity of faculty mentors offered to its scholars, the quality of research UGA creates, and the support the program offered. PREP@UGA emphasized its dedication to its scholars success by allowing us to take graduate level classes, take a GRE prep course, have ability to travel to topic specific conferences, and form meaningful professional relationships with the research community. Without these resources, I would not feel as confident or prepared in embarking on the graduate path.

I hope my year at PREP@UGA will provide me with the basic resources I need to excel in a competitive graduate program.

I am spending the year in Dr. Nancy Manley’s lab with Dr. Julie Gordon as my research mentor.

Objectives and hypothesis:

The notch signaling pathway is highly conserved amongst multicellular organisms and it regulates cell fate specification during development and tissue maintenance. There are four Notch receptors in vertebrates and for my project, I will be focusing on Notch1. When the Notch1 receptor comes into contact with a ligand, it induces a proteolytic cleavage of the Notch1 Intracellular Domain which then enters the nucleus and modifies gene expression.

Hypothesis: Preliminary data generated by the Manley Lab shows “a clear phenotype after thymic epithelial cell specific Notch1 deletion” suggesting there is a connection between Notch1 and TECs. We hypothesize Notch1 is required for TEC formation and maintenance therefore deleting Notch1 will result in an abnormal thymic epithileal cell phenotype. My project is a time-course analysis of TECs using fetal stage to post-natal stage mice. I will be focusing on the earlier stages of TEC development in relation to the absence of Notch1. By identifying the earliest time point in which deletion of Notch1 is able to affect the progenitor cell phenotype of the mice, we can begin to understand the role of Notch in TECs.

Techniques:

In this project, I will be utilizing cre-lox technology to create conditional Notch1 knockout mutants in thymic epithelial cells.  Foxn1 is expressed in TECs, therefore crossing FoxN1 cre mice with a conditional Notch1 mouse strain will delete Notch in TECs.

To analyze the role of Notch1 in the development of TECs, I will use immunohistochemistry to stain for TEC progenitor markers to identify meaningful differences between the Notch1 mutant thymus and control thymus.

My name is Cybelle Tabilas and I am a PREP@UGA scholar.

Hi, my name is Alexis Thomas.  I grew up in Rosedale, Indiana and went to college at Indiana University in Bloomington, Indiana and graduated with a degree in microbiology.

Growing up, I was in and out of doctors’ offices and hospitals.  I became interested in disease and what makes people sick. That led me to become a human biology major and set a track for medical school.  Upon arriving at IU, I heard a presentation on microbiology and I was so intrigued by all the different types of bacteria and pathogens, that I changed my major that day.

Until going to IU, I was never really exposed to the possibility of research as a career path. I began working in a lab my sophomore year and discovered that I enjoyed research. I have always liked doing puzzles.  I view research and scientific discovery as a never-ending puzzle. I believe this is what draws me to research.

Even though I started research in my sophomore year, it was not until my senior year that I had felt that I had explored other fields and options, enough to be confident in my decision to go to graduate school and do biomedical research. I am interested in and host pathogen interactions and drug and vaccine development.

It is my plan to work in industry or a government lab in the future. As I decided later that I wanted to go to graduate school, I knew I needed time to learn more about the process and the various career paths available.

When I discovered the PREP program I knew it was the perfect program for me.  I am able to do full time research in a field that I am interested in as well as interact with graduate students, something that I did not do as an undergrad.  The program allows for me to get an inside look at graduate school and has affirmed my decision to pursue a career in research. PREP at UGA was perfect for me because of the focus on infectious diseases this closely aligns with my interests and goals.

My research mentor is Dr. Carmen Herrera and my faculty mentor is Dr. Stephen Trent.

A focus of the Trent lab is lipid A. Lipid A is the endotoxic portion of Lipopolysacchride or LPS,which is a large molecule on the surface of gram-negative bacteria that has many functions, one of which is inducing an innate immune response. Lipid A is recognized by the immune system via the Toll-like receptor 4/myeloid differentiation factor 2 complex.  Activation of this complex by wt ecoli leads to a strong immune response.  Lipid A is a diverse molecule, whose structure varies between gram negative bacteria.  These bacteria contain enzymes that alter the structure by changing the number of acyl chains, phosphate groups, and polar functional groups.  The structure of the lipidA molecule expressed by a bacterium determines how strong the immune response will be.

The goal of my project is to insert lipid A modification genes from other organisms into the E.coli chromosome.   Alteration of the lipid A will allow it to be used as a vaccine adjuvant by producing a milder immune response.  To alter the structure of the lipid A I will be cloning genes into a plasmid with an antibiotic resistance cassette.

I will use the lambda red recombination system to insert genes as well as delete others.  Once a modification has been confirmed genetically through PCR and sequencing, we can isolate the LipidA molecule from the bacteria, and visualize the changes through radiolabling and running it on a TLC plate.

My name is Alexis Thomas and I am a PREP@UGA scholar.

Hi, my name is Nicole Williams. I received my Bachelor’s degree in Biological Sciences from Atlanta Metropolitan State College in Atlanta, GA.

My earliest memory of wanting to go into science was in my 9^th grade biology class. I always thought that I was going to follow in the footsteps of my mom and go into criminal justice like her, but I became very interested in this subject called biology; the study of life and organisms. Even though in 9^th grade it was on a broad scope and we covered many topics, I was most fascinated when we discussed cells. I was in awe that these little things did so much. And from there I started asking questions because I always wanted to know more.

I decided on a career in research when I was at my undergraduate institution. There was a program in place for science majors called the Mathematics, Engineering and Science Achievement program or MESA. Through this program we attended seminars where we heard about various careers in science to determine what track we wanted to take such as Pre-Med, Pre-Nursing or Research. It was then that I was able to realize the track I eventually wanted to follow was biomedical research. I believe that research is perfect for me as I am naturally curious. I love the process of formulating a question or hypothesis and following the necessary scientific steps to finding an answer.

My general area of interest is in infectious diseases. I became fascinated with this while I was in my Microbiology class and further fueled my interest when I enrolled in Virology and audited a Medical Microbiology class. I am most interested in understanding exactly how these infectious pathogens interact with its host in order to find appropriate vaccine targets. Ultimately, I want to be involved in research that explores anti-viral and vaccine design and development.

My long term career goal is to secure a position as a principal investigator, leading my own lab in a government agency.

I decided to join PREP@UGA because it not only provides me the opportunity to be a more competitive applicant for a graduate program but it also allows me to participate in cutting edge research that has great societal impact.

The PREP program has been the best choice for me because I am given the opportunity to practice more for the GRE with a tutor they have provided while in a research lab acquiring new skills and techniques that I can take with me to graduate school. We as PREP scholars are also given a sneak peak at what it’s like to be a graduate student by taking a few graduate level courses both formally and informally. I am also fortunate to have our program director and coordinator who both genuinely care about our success in the program.

By the time I’ve completed the PREP program, I hope to be more confident in my research techniques and able to think more critically as expected on the graduate level.

Currently I am working under the direction of my faculty mentor Dr. Ted Ross and research mentor Don Carter an Assistant research scientist in his lab. One of the current projects in Dr. Ross’ lab explores vaccine design and development for seasonal and pandemic influenza.

The direction of my project is to identify the influence of prior exposure to future infection or vaccination. We want to gain a better understanding of pre immunity on subsequent vaccination to seasonal strains of influenza. Antigenic drift occurs when there are point mutations in a viral gene that lead to antigenic changes and vaccine escape. This results in the different influenza vaccines year to year. The hypothesis of my project is that significant changes in certain amino acid residues can have a direct correlation between cross reactivity in certain influenza strains. Meaning, prior exposure to one strain can potentially provide protection or an immune response to future exposure of another.

So far, I have used bioinformatics tools to identify amino acid residues of importance that are similar or divergent in influenza strains. I have also completed transformations which allow me to amplify my plasmid DNA containing viral genes expressing mutated amino acid residues. These will be further used to create virus like particles or VLPs. Using VLPs in the lab allows us to work with particular influenza strains safely without the potential to cause infection because they do not contain any viral genetic material and are non-infectious.

Further along in my project, I will also use the technique of reverse genetics to express these mutations in amino acids sequences in the live virus. These will be used to further test the validity of their importance.

My name is Nicole Williams and I am a PREP@UGA Scholar.