Our Team

Pam Lein

Professor of Neurotoxicology, Lab Principal Investigator

Home town: Buffalo, NY
Education: B.S., Biology, Cornell University
M.S., Environmental Health, East Tennessee State University
Ph.D., Pharmacology and Toxicology, University of Buffalo
Postdoctoral Fellowship, Molecular Immunology, Roswell Park Cancer Institute

My research goal is to determine how environmental stressors interact with genetic susceptibilities to influence the risk and severity of neurodevelopmental disorders and neurodegeneration. Altered patterns of connectivity are associated with neurological deficits: therefore, my research program focuses on investigating how environmental contaminants, chemical convulsants and inflammation perturb neuronal connectivity as determined using biochemical, morphogenic and electrophysiological endpoints. We are also developing biomarkers of OP neurotoxicity and testing novel therapeutic approaches for protecting against the neurodegenerative effects associated with neurotoxic pro-convulsants.

Dr. Lein is affiliated with the following graduate groups: Pharmacology and Toxicology; Molecular, Cellular and Integrative Physiology; Neuroscience; Integrative Pathobiology; and Forensic Sciences. Dr. Lein is also a mentor for the Advancing Diversity in Neuroscience Research (ADNR) Honors Program at UC Davis, which supports diverse upper division undergraduate students who plan to pursue a PhD in neuroscience. 

Email: pjlein@ucdavis.edu

Ana Cristina Goncalves Grodzki

Associate Project Scientist

Home town: Curitiba, Brazil
Education: B.S., Biology, Federal University of Parana
Ph.D., Ribeirão Preto Medical School, University of São Paulo
Postdoctoral Fellowship, Immunology, NIH, Bethesda, MD

While at the Federal University of Parana, I met an amazing professor, Dr. Maria Celia Jamur who helped me to see science as a fun and fulfilling profession. During my PhD at Ribeirão Preto Medical School, University of São Paulo, I studied the progression of maturation and differentiation of mast cells in rodents and the process of migration of immature mast cells from bone marrow to the peripheral tissues. During my post-doctoral training at NIH, I was mentored by another outstanding scientist, Dr. Reuben Siraganian, and studied intracellular signal transduction pathways in mast cells that lead to the release of inflammatory molecules. Here at UC Davis, I am again under an amazing mentor, Dr. Pam Lein. In Dr. Lein’s lab I am a Project Scientist investigating the effects of organophosphorus pesticides (OPs) on nerve-immune cell interactions, specially implicated in airway hyperreactivity. This research will help us to understand how environmental factors influence susceptibility to airway disease. I am also the primary technical contact for the high content imaging equipment in Dr. Lein’s lab., which is part of the Biological Analysis Core of the MIND Institute Intellectual and Developmental Disabilities Research Center (IDDRC). My time outside the lab is as fun and productive as the time inside lab. I enjoy traveling, being outdoors, and spending time with my family. My husband John and I have 2 bright and fun kids: Gabriela and Leo. And we all love to take care and have fun with our dog Zoey.

Email: cgrodzki@ucdavis.edu

Donald Bruun

Academic Program Management Officer-Lab Manager

Home town: Shullsburg WI
Education: B.S., Creighton University

In our ever changing world there is a critical need to be able to respond quickly and effectively to exposures to neurotoxic chemicals. These chemicals may be released either accidentally or intentionally and have the potential for impacting large numbers of the population. Treatments must be developed to protect first responders and also minimize the neurological damage in individuals that survive the initial exposure. My research as part of the CounterACT project involves investigating novel neuroprotectants following acute exposures to organophosphates which are powerful acetylcholinesterase inhibitors or the rodenticide TETS which blocks GABAA receptors in the central nervous system. Our research indicates that anti-inflammatories and neural steroids may prove to be effective either alone or in combination to minimize the neural damage following acute intoxicant exposures.
In my role as lab manager I work with lab members to ensure that every one is working safely and efficiently.
When I am not in the lab I like spending time with my wife and dogs, creating stained glass and other objects of art, being outdoors, camping and going on the occasional bigfoot search.

Email: dabruun@ucdavis.edu

Anthony Valenzuela

Staff Research Associate

Home town: Antioch, CA
Education: B.S., Neurobiology, Physiology and Behavior, UC Davis
M.S., Animal Behavior: Physiological Bases of Animal Behavior, UC Davis

I’m a lifetime Aggie. I earned both my B.S. and M.S. at UC Davis, and I’ve been a member of the research staff since 2008. My research background is in neurobiology, animal behavior, pharmacology and toxicology. I work on a variety of projects in the Lein Lab, performing laboratory rodent research, histological analysis and analytical chemistry.   

In my free time, I enjoy science fiction and fantasy stories, video games and home improvement projects.

Email: aevalenzuela@ucdavis.edu

Mei-Yun Cheng

Graduate Student

Home town: Palo Alto, CA
Education: B.S., Animal Science, UC Davis

I am a PhD student in the Molecular, Cellular and Integrative Physiology graduate group. As a third-year undergraduate, I was first introduced to biomedical research through joining the Lein lab as a research intern in CounterACT and completing an honors thesis on the evaluation of neurogenesis in a juvenile rat model of acute organophosphate intoxication. Upon graduation, I continued working in the lab as a junior research specialist investigating the role of the plasminogen activator system (PAS) as a biomarker and therapeutic target for mitigating neuroinflammation in a transgenic rat model of Alzheimer’s disease (AD).

As a graduate student, I am continuing my studies of the PAS in AD - specifically in its association with the neuroinflammatory response and in altering the blood-brain barrier (BBB). I am interested in its role as a mediator between the CNS and peripheral inflammation. Additionally, I will be determining the impact of traffic-related air pollution (TRAP) on modulation of BBB integrity, microglial and astroglial activation, and AD-relevant pathology in the same transgenic rat model. Over the course of my scientific training, I hope to elucidate potential mechanisms of TRAP-induced neuroinflammation and BBB dysfunction.

Outside of the lab, I love serving in college ministry at my church, enjoying the outdoors, all things music, and going to coffee shops. Feel free to email me if you’d like to connect!

email: mytang@ucdavis.edu

Rebecca Wilson

Graduate Student

Home town: Livonia, MI
Education: B.S., Biology with Honors, Roosevelt University, Chicago
M.S. Biological Sciences, Neuroscience, DePaul University

In 2015, I received my B.S. majoring in biology and minoring in chemistry and calculus from Roosevelt University, where I first fell in love with doing research. Initially, I worked in glaucoma research with Dr. Kelly Wentz-Hunter assessing possible RNA responsible for alterations in the trabecular meshwork of the eye. I also conducted ecological restoration research in Tanzania, Africa, on the Amani Nature Reserve with Dr. Norbert Cordeiro measuring seed rain. Following graduation, I worked towards my M.S. in biological sciences with a focus in neuroscience under the watchful eye of Dr. Dorothy Kozlowski in Chicago. In this lab, I completed my thesis assessing sex differences in behavioral responses to repeat subconcussive injuries. Afterward, I had the opportunity to work for a pharmaceutical research company, Aptinyx, introducing and optimizing animal models of neurodegeneration for use with their compounds. I joined the lab of Pam Lein during the Summer of 2020. My current research directive is focused on the effect of PCBs on neurodevelopment and how modulation of the metabolism of PCBs may alter neurotoxic outcomes. I will be looking in vitro and in vivo to better elucidate the mechanism of PCBs involvement in cellular and behavioral outcomes following exposure. 

When not in the lab I enjoy reading, spending time with my dog, going on trips, and cooking! 

Email: rjwilso@ucdavis.edu

Ryan Hogans

Graduate Student

Home town: Carmel Valley, CA
Education: B.S., Biology, Northern Arizona University

I am a graduate student in the Molecular, Cellular and Integrative Physiology (MCIP) graduate group. My interest as a scientific investigator is in the determinants of disease etiology. As an undergraduate researcher I studied molecular genetics with Dr. Nathan Nieto. We investigated the prevalence of intracellular pathogens in threatened Arizona wildlife. Prior to attending graduate school, I worked in industry biotechnology developing molecular diagnostics tools and therapeutics to study and utilize the biology of small nucleic acids.

As a graduate student in the Lein lab I will be investigating factors secreted by cells in the brain during aging that increase susceptibility to neuroinflammation and neurodegeneration. Circulating biomolecules play many important roles in physiology. By describing the molecular and cellular actors at play in the brain during advanced age, we can refine our understanding of neurodegenerative diseases for which age is the primary risk factor.

Outside of my studies I love to spend my time playing jazz and blues, or biking and hiking where I can spot wildlife.

Email: rehogans@ucdavis.edu

Jessie Badley

Graduate Student

Home town: San Francisco Bay Area, CA
Education: B.S., Biochemistry, UC Davis

I was born and raised in the San Francisco Bay Area and am definitely a product of my environment. I am a proud first-generation student and UC Davis Aggie. I transferred to U.C. Davis in my junior year, obtaining my B.S. in Biochemistry in 2020 and have been working in labs for the last four years. I am currently a PhD student in the Pharmacology and Toxicology graduate group. My undergraduate research focused on method development and metabolomics in Dr. Oliver Fiehn’s lab. I joined the Lein lab in Winter 2021, and my current research focus is the CYP-mediated metabolism and biotransformation of PCBs and how modifying these metabolic pathways effects neurological development.

I am an ex-pastry chef, rare plant collector, dog enthusiast (especially my dog, Boscoe), crafting connoisseur, and avid bike rider. I am extremely blessed to have gotten this far in my education and hope to bring a diverse perspective to my PhD studies. My goal is to not only push the boundaries of science and research, but also advocate for those underserved and underrepresented.

Email: jrbadley@ucdavis.edu

Pedro Negri Bernardino

Postdoctoral Fellow

Home town: Piracicaba, São Paulo, Brazil
Education: PhD, Integrative Pathobiology, UC Davis
DVM, São Paulo State University (UNESP – Botucatu)
M.S., General Veterinary Medicine/emphasis in Clinical Microbiology, São Paulo State University (UNESP – Botucatu)

I recently received my PhD in Integrative Pathobiology. During vet school, I worked in two different labs where I learned multiple techniques in cellular and molecular biology, studying the prevalence of genetic diseases in buffaloes in one lab and the immunomodulatory properties of natural compounds in the other. After my residency in Large Animal Internal Medicine, I earned my Master’s degree with a focus on microbiology, studying the effects of natural and synthetic compounds against Corynebacterium pseudotuberculosis.

My main career goal is work in translational research, where I can bring bench work findings to the clinical field. Joining the Lein Lab has enabled me to gain skills with animal models while studying the pathogenesis and the real world problem of epilepsy due to organophosphate intoxication.

Email: pnberna@ucdavis.edu

Lukas Skuja

Graduate Student

Hometown: Oakland, CA
Education: B.S., Neuroscience, Brown University

I'm a PhD student in the Neuroscience Graduate Group and working with Denali Therapeutics through the UC Davis Advanced Degree Program for Corporate Employees. Thus, I'm being co-mentored by Dr. Pamela Lein at UC Davis and Dr. Gilbert Di Paolo at Denali Therapeutics. My research interests are aimed at better understanding the molecular and cellular mechanisms that underlie neurodegeneration - with the ultimate goal to help patients affected by neurodegenerative diseases. Some adjacent areas of interest include neuroinflammation, lysosomal dysfunction, and neurovasculature biology.

I was born and raised in Oakland, love the Bay, and rep it along with the Golden State Warriors. I like watching and playing sports/games generally, and especially love getting out in nature - hiking, skiing, whitewater kayaking... I've worked as a whitewater river rafting guide for a good chunk of time and actually spent about 6 months in New Zealand after undergrad working, traveling, and living in a van down by the river!

Email: llskuja@ucdavis.edu

Heui Hye (Heehay) Park

Graduate Student

Home town: Jeddah, Saudi Arabia
Education: B.S., Neurobiology, Physiology, and Behavior, UC Davis

I am a PhD student in the Pharmacology and Toxicology graduate group. I came to the U.S. in 2014 to earn my undergraduate degree at UC Davis. My first step into research was studying decision-making processes in Dr. Timothy Hanks’s lab at UC Davis as an undergraduate researcher. After graduating from UC Davis, I worked in Dr. Mehrdad Shamloo’s lab at Stanford University as a research assistant for three years to gain more experience in neurodegenerative disease research. I joined the Lein Lab in the Winter 2021 to study the effects of traffic-related air pollution (TRAP) on Alzheimer’s Disease (AD) pathogenesis with a focus on the role of the lung-brain axis. My personal and long-term career goal is to do research that can be helpful in improving daily lives of AD patients and their families.

Other than science, I like coffee, listening to or reading books, and watching movies.

Email: hhppark@ucdavis.edu

Maria Muñoz

Graduate Student

Nathifa Nasim 

Graduate Student

Hometown: San Jose, CA
Education: B.S., Neurobiology, Physiology, and Behavior, UC Davis

I am a graduate student in the Biochemistry, Molecular, Cellular, and Developmental Biology (BMCDB) graduate program. I completed my undergrad at Davis in 2022, majoring in Neurobiology. As an undergraduate researcher, I worked in Dr. Earl Carstens’ lab focusing on itch and pain pathways, in addition to Dr. Lee-Way Jin’s lab at the MIND Institute; there, I worked on the soluble epoxide hydrolase (sEH) pathway and Alzheimer’s disease. This experience sparked my long term research interest in exploring the relationship between neuroinflammation and neurodegeneration. I joined the Lein lab in Spring 2023, hoping to elucidate the mechanisms by which traffic-related air pollution (TRAP) contribute to Alzheimer’s disease.

Outside of the lab, I love reading, painting, watching movies, baking/cooking, and anything craftsy.

Email: nnasim@ucdavis.edu

Chelsea Unkel 

Graduate Student

Hometown: Folsom, CA
Education: B.A., Psychology, California State University, Sacramento

Currently, I am a Ph.D. student in the Pharmacology and Toxicology Graduate Group at UC Davis. I graduated from California State University, Sacramento, with a bachelor’s degree in psychology and worked as a neuroelectrophysiology technician. This work introduced me to the world of neurotoxicology and epilepsy. I joined the Lein Lab in Spring 2023 to study the role of neuroinflammation following acute organophosphate intoxication and evaluate potential therapeutics to reduce long-term sequalae, emphasizing translational models and understanding of epileptogenesis.

Other than science, I love spending time at home with my wife and our fur family, hosting gatherings, reading, and enjoying homemade espresso, gardening, and the California sunshine.

Email: cmcrowe@ucdavis.edu

Brittany Davis 

Graduate Student

Hometown: Lilburn, GA
Education: B.S., Animal Science, University of Georgia
M.S., Animal Science, Colorado State University

I am a DVM-Ph.D. student in the Neuroscience Graduate Group. My master’s studies focused on animal behavior and welfare; my thesis aimed to evaluate the behavioral effects of tryptophan supplementation in horses. I went on to work in biomedical research, where I grew to appreciate how important both scientific and veterinary expertise are when employing animal models to better understand disease/disorder processes. As a dual degree student, I aspire to contribute to research aimed at improving the quality of both human and animal lives. My research in the Lein lab is focused on understanding how organophosphate exposure affects the blood brain barrier, with the goal of identifying therapeutic strategies to mitigate neurotoxicity.

Outside of lab, I love spending time with animals and exploring nature.

Email: bpdavis@ucdavis.edu

Aishwarya Bhusal 

Graduate Student

Hometown: Kathmandu, Nepal
Education: B.S., Biochemistry and Molecular Biology, UC Davis

Email: abhusal@ucdavis.edu

Rosalia Mendieta 

Graduate Student

Hometown: Calistoga, CA
Education: B.S., Animal Biology, UC Davis

I am a first-generation Ph.D. student enrolled in the Pharmacology and Toxicology Graduate Group at UC Davis. I obtained my associate degree in biology at Solano Community College and transferred to UC Davis in 2020. As an undergraduate researcher, I studied the molecular mechanisms by which chemicals induce seizures, leveraging the zebrafish model. During my senior year, I completed a practicum project evaluating the role of cAMP response element binding protein (CREB) in the developmental neurotoxicity of tetrabromopyrrole. After graduation, I worked in the Lein Lab, assisting in the investigation of how developmental exposure to PCBs causes neurotoxicity.  As a graduate student, I am motivated to contribute more to our understanding of the mechanisms of PCB toxicity and how developmental neurotoxicity may be influenced by the route of exposure.

In my free time, I enjoy spending time with family and friends, indulging in crafts, reading, and taking care of my collection of houseplants.

Email: rmendieta@ucdavis.edu
Or connect: linkedin.com/in/rosalia-mendieta-583b151b7

Matthew Armstrong

Postdoctoral Fellow

Email: mjarmstrong@ucdavis.edu

Suzette Smiley-Jewell 

Scientific Program Manager

Hometown: San Jose, CA
Education: B.S., Environmental Toxicology, UC Davis
Ph.D., Pharmacology and Toxicology, UC Davis

My primary job is serving as the Scientific Program Manager for the UC Davis CounterACT Center of Excellence. However, I enjoy using my skills as a scientific editor and web content manager to help out in the Lein lab. In the past, I served as a Principal Editor for the Center for Health and Environment and as an Academic Coordinator at the Center for Neuroscience, where I managed two NIH T32 graduate student training grants. While I didn't always enjoy the ups and downs of doing experiments, I've always loved learning about science and helping people get their results published and ideas funded.

Outside of work, I enjoy being with friends and family, horseback riding and chasing around my 2 dogs and hens.

Email: smsmiley@ucdavis.edu