Poster Session Abstracts
Alumni Abstracts
Evaluating Rod Photoreceptor Mosaic Topography using AOSLO
Heather Heitkotter ’161, Erica N Woertz 2, Jenna A Cava 3, Mina Gaffney 3, Iniya Adhan 2, Robert F Cooper 3,4, Emily J Patterson 5, Joseph Carrol 1,3. 1Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA, 2Medical College of Wisconsin, Milwaukee, WI, USA, 3Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA,, 4Joint Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA, 5Institute of Ophthalmology, University College London, Bloomsbury, London, UK
Adaptive optics scanning light ophthalmoscopy (AOSLO) enables noninvasive visualization of the photoreceptor mosaic within the living eye. Cone photoreceptors are responsible for high acuity color vision and are easily resolved with AOSLO, which enables quantitative assessment of cone density and spacing. However, there are far fewer in vivo AOSLO imaging studies on the cells responsible for nighttime vision – the rod photoreceptors. Information regarding rod structure has been gleaned mainly from patients with diseases where cone structure is severely disrupted, such as achromatopsia or blue cone monochromacy. Loss of rod structure and function is known to occur in many vision-limiting pathologies, but how the rod mosaic may differ between healthy controls and individuals with multifactorial visual impairment, such as that seen in albinism, remains unclear. Here we developed a method to quantify rod density from rod spacing, eliminating the requirement for complete resolution of the rod mosaic in individuals with contiguous rod mosaics. Once this method was validated, data acquired in both individuals with normal retinal structure and individuals with albinism were analyzed to assess rod density across retinal eccentricity. Utilizing this method, we found that rod density in albinism is consistent with expected normative values, in contrast with prior literature reports from animal models of albinism.
Identifying Biomarkers for Central Neuropathic Pain Following Spinal Cord Injury and Subsequent Treatment
B.L. Avonts’17, R. G.Fessler, B. T. David. Department of Neurosurgery, Rush University, Chicago, IL
Central neuropathic pain (CNP) commonly develops in patients after spinal cord injury (SCI), causing debilitating symptoms and sensory abnormalities such as allodynia and hyperalgesia. Pharmaceutical and alternative surgical treatments are inconsistent or ineffective at mitigating the pain. CNP regularly presents itself around a year after the injury, resulting from permanent cellular and anatomical changes from a strong inflammatory response. Previous scientific studies have demonstrated greater efficacy of treatments when delivered preemptively, but there is currently no marker to indicate which individuals are likely to develop CNP. Thus, it is necessary to investigate the physiological processes contributing to sensory changes seen with CNP. In the present work, we characterize physiological changes which contribute to the development of CNP to determine vulnerability for developing the disease. The overall hypothesis of this proposal is that physiological indicator(s) will identify the earliest point of differentiation between vulnerable and non-vulnerable subjects to determine the most efficacious window for treatment. Inflammatory, autonomic, and behavioral changes were significantly different in rats with CNP following SCI compared to rats without CNP. To further understand therapeutic potential, we also determined the attenuation of CNP following treatment with bone marrow mesenchymal stem cells (BMSCs). These experiments will provide new insights into clinical indicators to predict the onset of CNP and improve patient outcomes through preemptive treatment with BMSCs.
Complicating narratives of sexual minority mental health: An intersectional analysis of frequent mental distress at the intersection of sexual orientation, gender identity, and race/ethnicity
Tubanji Walubita ’19 1, Ariel L. Beccia 2, Esther Boama-Nyarko 2, Eric Y. Ding 2, Katarina A. Ferrucci 2, Bill M. Jesdale 2
1. Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States
2. Department of Population and Quantitative Health Sciences, University of Massachusetts Medical School, Worcester, Massachusetts, United States
Evidence suggests that sexual minorities experience mental health inequities. However, few studies have examined mental health outcomes in sexual minorities while including intersecting dimensions of social identity. This study had two objectives: 1) to quantify the prevalence of frequent mental distress among U.S. adults across intersecting social identity categories and 2) to evaluate the contribution of intersectional interactions to observed inequities. We used data from the Behavioral Risk Factor Surveillance System 2014–2019 (N=1,024,261) to perform an intersectional Multilevel Analysis of Individual Heterogeneity and Discriminatory Accuracy (I-MAIHDA). Participants were nested in 45 intersectional groups defined by combining 3 sexual orientation (gay/lesbian, bisexual, heterosexual), 5 gender identity (transgender women, transgender men, gender nonconforming, cisgender women, cisgender men), and 3 racial/ethnic (non-Hispanic Black, Hispanic/Latinx, non-Hispanic White) categories. We estimated the predicted probability of frequent mental distress for each stratum. We then calculated the Variance Partition Coefficient (VPC) and Proportional Change in Variance (PCV). We found that multiply marginalized groups, particularly those including sexual and gender minorities, tended to have the highest prevalence of frequent mental distress. Groups with racial/ethnic minorities were equally represented among low and high prevalence groups. The VPC indicated that slightly over 10% of observed variance in prevalence was attributable to group-level differences, while the PCV revealed that a small but meaningful amount of observed heterogeneity in prevalence was due to intersectional interactions between the dimensions of social identity. I-MAIHDA is a promising method for examining the patterning of sexual orientation-based mental health inequities at the population level.
Encapsulating Pathways in a Bacterial Organelle to Sequester Toxic Intermediates
Brett J. Palmero ’20 1, Danielle Tullman-Ercek 2, 1Interdisciplinary Biological Sciences Graduate Program, Northwestern University, Evanston, IL, United States, 2Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, United States; Center for Synthetic Biology, Northwestern University, Evanston, IL, United States.
In nature, certain species of bacteria have evolved to utilize bacterial microcompartments (MCPs) to exert temporal and spatial control over metabolism. MCPs are made up of large inducible proteinaceous shells that encapsulate the enzymes for specific metabolic pathways. The shells of the MCPs contain pores that allow selective diffusion of the encapsulated pathway’s substrates and products. Pathway encapsulation in an MCP is hypothesized to localize enzymes and metabolites to increase pathway flux, sequester volatile or toxic pathway intermediates from the rest of the cell, and prevent intermediates from participating in non-encapsulated pathways. One example of an MCP is the 1,2 propanediol utilization (Pdu) MCP found in Salmonella enterica that encapsulates the 1,2 propanediol degradation pathway. The Pdu MCP has been shown to sequester the toxic intermediate propionaldehyde away from the cytosol to protect the cell as well as enhance pathway activity. MCPs have the potential to be a tool for metabolic engineers to encapsulate and enhance the activity of heterologous pathways. To take advantage of encapsulating pathways in the MCP, we must understand how encapsulation influences heterologous pathway flux. We will study the effects of encapsulation on several heterologous pathways in the well-characterized Pdu MCP in S. enterica. Here, we will discuss the impact on the production of a precursor for polymers which, like the native pathway, involves a toxic intermediate. With this project, we will target pathway enzymes for efficient encapsulation and use growth and chromatography to assess cellular health and product concentrations to gain insights into how encapsulation in the Pdu MCP alters pathway flux for this industrially relevant product.
Student Abstracts
Determining Rostral and Caudal Boundaries of Structures Involved in Rhythmic Breathing Patterns Using Thionin Staining
Deniz Akpinar, Kaiwen Kam, Rosalind Franklin University of Medicine and Sciences
The preBötzinger complex in the brainstem is known to be responsible for the rhythm of breathing. To study the role of the preBötzinger Complex in breathing, rhythmically active coronal tissue slices containing this region are generated. However, the preBötzinger Complex may be modulated by cell bodies outside this region, but still contained in these tissue slices. The goal of my project is to create and optimize a Thionin staining protocol based on the literature to determine the rostral and caudal boundaries of the slices used in the experiments conducted in the lab. Mice of varying ages (P0, P1, P2, P3) are sacrificed, perfused, dissected, mounted and cut into coronal sections of different thicknesses using a microtome. Each slice is stained with the optimized Thionin procedure and observed under an electron microscope and saved as images. Using a visualization software called ImageJ, the sections are stitched together to reform each coronal slice and annotated to reflect nuclei where the cell bodies of certain neurons are concentrated. Identification of certain nuclei act as landmarks, including inferior olive, nucleus ambiguus and facial nucleus, in determining rostral and caudal level of where the slice has been taken when compared to the previous literature. Thionin staining procedure was optimized and repeated for slices with varying thicknesses (200µm, 300µm, 500 and 550µm, 600µm). The concentration of the Thionin stain coupled with the length of immersion into dye is found to be essential for successfully staining Nissl bodies and indicating nuclei. However, the staining process utilized during this research project resulted in damage to the slices. Further research may be conducted to decrease the amount of damage and drying caused to stained tissues.
Brain Age Index Predictions from Neural Networks Can Act as Potential Biomarkers in Estimating Chronic Disease States
Sugata Banerji, Arthur Bousquet, Mark Conneely, Sara Zelenberg, Bita Aslrousta, Jessica Teichman, Department of Mathematics & Computer Science, Lake Forest College, Lake Forest IL, 60045
Aging and chronic disease states such as ongoing illicit substance abuse/dependence (SA) or alcoholism (AA) are known to change the brain’s appearance. A potential biomarker for predicting chronic disease states might lay in age prediction from brain Magnetic Resonance Imaging (MRI) imaging. Convolutional neural networks (CNNs) are suitable tools for any supervised image-prediction application and have been used on MRI imaging in the past. In the present study, we developed an ensemble model (r^2 = 0.84) from CNNs models trained on two-dimensional slices of axial FLAIR and T2 weighted MRI images at the level of anterior commissure and the frontal horns of the lateral ventricles to predict the brain age. We then calculated the brain age index (BAI) of the patients—the difference between the predicted age and the actual age—and evaluated BAI as a potential biomarker for chronic disease states. ANOVA testing of BAI, hypertension (HTN), and SA illustrated a statistically significant difference of means (p=0.000). No significant correlation existed between the BAI and HTN, diabetes mellitus (DM), and mild traumatic brain injury (mTBI). The presence of HTN was inversely correlated with BAI (P=0.000). We then collapsed HTN and diabetes mellitus into one dimension (0=None, 1=HTN, 2=DM, 3=Both) against BAI. A kNN model (k=20) of patients with at least one code of mTBI, AA, or SA visually split this two-dimensional space. Regions identified with AA and/or SA dominated regions corresponding to a higher predicted age. This relationship disappears when patients with no such codes are included, possibly indicating missing codes or other factors. Future research will focus to increase the accuracy of estimating AA or SA in relation to the BAI.
Characterization of a Rapid Defensive Behavior in a Recently Introduced Model Gastropod
O.H. BERG 1, A. BOUTKO 2, V. K. MISTRY 3, W. N. FROST 2, J. W. BROWN 3;
1Neurosci., Lake Forest Col., Lake Forest, IL; 2The Chicago Med. Sch., 3Sch. of Grad. and Postdoctoral Studies, Rosalind Franklin Univ., North Chicago, IL
The aeolid nudibranch Berghia stephanieae is a recently introduced model species being studied as the subject of a five-PI BRAIN Initiative collaboration. It is on course to become the first transgenic gastropod mollusk, in which we hope to conduct all-optical neurophysiological recording and stimulation using genetically encoded indicators. Berghia’s approximately 10,000-neuron central nervous system makes it an attractive model species, as it allows one to draw correlations between genes, brain, and behavior and to manipulate individual neurons and complete neural circuits. Furthermore, Berghia’s relatively simple central nervous system and distributed peripheral nervous system provide opportunities to ask questions about how these two neural organizational schemes cooperatively generate behavior. In the present study, we characterize and draw basic inferences about the neural bases of “bristling,” Berghia’s most dramatic behavior, in which dozens of appendages, called cerata, raise from the animal’s dorsum in a rapid, targeted, and coordinated fashion in response to an aversive stimulus. Berghia’s ceratal tips contain noxious nematocysts that are internalized when the animal feeds on anemone prey. Thus, when Berghia bristle, they deter predators by orienting their cerata towards the offending stimulus. Bristling was elicited through either aversive tactile or chemical stimulation to different parts of the body using a von Frye Hair of 1M NaCl. Filming bristling responses in immobilized animals revealed three findings. First, the bristling response was initiated close to the stimulus and then propagated from head to tail. Second, decerebrated animals continued to produce a local bristling response, but ceased a coordinated, full-body response. Third, repeated stimulation to individual body loci induced response habituation in intact animals. These findings implicated the involvement of the peripheral and central nervous systems in mediating the early and late, integrative components of the bristling response, respectively. Bristling was also elicited through chemical stimulation of freely locomoting animals. In this case, bristling was accompanied by concomitant defensive behaviors, such as body shortening and avoidance turning. Specifically, stimulation of the head drove body shortening, and a subsequent, abrupt turn away from the stimulus, while stimulation of the tail drove forward crawling. These findings provide a behavioral characterization on which future neurophysiological investigations can be conducted.
Latent Class Analysis (LCA) of Emerging Adults Perceived Stress Scale Scores (PSS) During COVID-19
J Benjamin Bitterman, Steven Miller Ph.D, Rachel Neff Greenley Ph.D, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60045
Emerging adulthood encompasses individuals between the ages of 18 and 25. These individuals experience various stressors during this period of their lives and COVID-19 inflicted various novel stressors while amplifying existing stressors. Assuming that emerging adults differentially perceive stress, we aimed to investigate latent classes of emerging adults based on their Perceived Stress Scale (PSS) scores. The PSS, designed to measure the degree to which individuals perceive life events as stressful, has displayed acceptable internal and test-retest reliability in previous studies. The sample analyzed was obtained from a longitudinal RFU-DPU study that deployed various surveys between 2018 and 2021, investigating health promotion behaviors, health risk behaviors, distal stressors, and other related constructs in emerging adults attending DPU. PSS data from the July 2020 follow-up survey (n = 265), during COVID-19, was dichotomized and Latent Class Analysis (LCA) was conducted to identify latent classes of emerging adults based on their PSS scores during COVID-19. LCA results suggest that the 4 class model fit the data best (BIC = 1904.616), indicating 4 classes of emerging adults that perceived stress differentially. Future investigation of demographics and class membership as well as predictors of class membership could yield more insightful results.
Physical Activity During Covid
Helena Blumenau ’23, Dr. Kristin Schneider, Emilie Green, Jesse Bahrke, Noelle Mastrili, and Melissa Mchugh, Department of Psychology, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60045
Covid-19 has significantly impacted all our lives in one way or another. Many daily activities, social interactions and work were halted to at least a certain degree. Physical activity was one of these factors that was influenced heavily by Covid-19, where many of us lacked the resources to continue with our normal exercise habits. The overall aim of this study is to understand what factors contributed to adults being physically active within the first six months of the Covid-19 pandemic. I came up with three central hypotheses surrounding participant’s physical activity during the pandemic: During the quarantine due to Covid-19, adults who live with someone else will be more physically active; During the quarantine due to Covid-19, those who have a chronic condition will be less active; Social support will be one of the main reasons why participants report being physically active during the pandemic. Similarly, a lack of social support due to inability to exercise with others will be one of the main barriers to physical activity during the pandemic.
The Initiation and Development of Human-Social Chatbot Interactions
Carolynn Boatfield, Isabel Krupica, Sophie Rasof, Xinyu Wang, Amelie Motzer, Dr. Vivian Ta, Psychology Department, Lake Forest College, Lake Forest, IL 60045
With the advancement of artificial intelligence, social chatbots are increasingly acting as social companions as people are increasingly interacting with social chatbots. Although studies have begun to investigate the social and health contributions of social chatbots, little is known about how social relationships between humans and social chatbots initiate and develop. We sought to address this in the current study. Users ( N=61) of Replika, a popular social chatbot, provided their motivation for using Replika and topics of discussion with their Replika. Thematic analyses were used to identify and extract meaningful patterns in responses. Participants initiated contact with Replika to seek social support, for health reasons, out of interest, and out of boredom. Topics of discussion varied and included intellectual topics, life & work, recreation, mental health, connection, current events, people, and Replika itself. These results help inform why people seek out social chatbots as social companions, how such interactions develop, and how such interactions may effectively contribute to social health and well-being. In addition, these results have implications on the design and functionality of social chatbots for optimal usage. Last, we provide future directions for human-chatbot interaction research.
Decomposing and Removing Environmentally Persistent Pharmaceuticals from Wastewater Using Organic Chemistry
Emma Clay-Barbour ‘23, Karen Gomez ‘22, Giselle Schiet ‘22, Samantha Stubbs ‘22, Mohammed AbuBakar ‘21, Rhyan Shanker ‘19, and Dr. Erica Schultz, Chemistry Department, Lake Forest College, Lake Forest IL 60045
Synthetic organic compounds, including pharmaceuticals, are a major water pollutant. The effects of water pollution are evident among individual organisms and larger ecosystems. This problem exists because wastewater treatment facilities are unable to remove these compounds through microbial degradation triggering a cascade of ecological consequences. To optimize the function of medications, medicinal chemists halogenate the active ingredients in pharmaceuticals, slowing drug metabolism and allowing humans to attain the desired effects of the medications we consume. We have developed a dehalogenation reaction that works in the presence of living bacteria. This non-toxic, biocompatible reaction is the first step toward a better wastewater treatment process for the removal of environmentally persistent pharmaceuticals and toxins.
Bluegill Sunfish ( Lepomis macrochirus) Regain Stability Quicker in Lower Horizontal Vortices Frequency
Reed Connor (Lake Forest College), Dr. Eric Tytell (Tufts University), Dr. Margot Schwalbe (Lake Forest College)
Fish encounter complex hydrodynamic environments while swimming, including turbulence generated by water moving over or around objects. Swimming in unsteady flows can be difficult, as unexpected turbulence can rapidly alter a fish’s stability or trajectory. It is unclear how quickly a fish can regain its stability once it experiences turbulence, especially from horizontal vortices that are shed by waterfalls or water spilling over a rock. Here, we challenged bluegill sunfish ( Lepomis macrochirus) in a flow tank to horizontal vortices shed at different rates and faster flow rates to test their stability over time. During a trial, a fish was positioned behind a custom flapper that generated horizontal vortices (flapping frequency = 1, 2, or 3 Hz) while swimming at one of three speeds and was recorded with three high-speed cameras to obtain the fish’s position relative to the flapper. Videos were digitized in MATLAB to quantify changes in the fish’s movement (distance, pitch, and elevation). Overall, fish recovered quickly from the flapper action and differences in swimming movements were observed under the various flow conditions and will be discussed. Bluegill sunfish are relatively stable in horizontal vortices likely due to passive properties of their bodies, and their sensory systems likely contribute to regaining stability after exposure to unsteady flows. This could suggest patterns of where bluegills live in the wild due to decreasing net energy expenditure.
INHIBITION OF THE HUMAN PLASMA MEMBRANE CITRATE TRANSPORTER EXPRESSED IN HEK293T CELLS
Sadiq W. Dabire, Dr. Ronald Kaplan & June Mayor, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60045
Citrate in the cytoplasm is an essential intermediate molecule for the biosynthesis of fatty acids and cholesterol; and the metabolism of glucose. Citrate molecules are transported in symport with Na+ ions into the cytoplasm through a special transporter in the cell membrane called the Plasma Membrane Citrate Transporter (PMCT). In this investigation, PMCT was overexpressed in Human Embryonic Kidney cells (HEK293T) after transfecting them with plasmids containing HsapPMCT gene extracted from Escherichia Coli DH5α cells. Next, varying concentrations of a potential inhibitor of the PMCT were introduced into the HEK293T cells before adding radioactive carbon-14 citrate stock. The influx of the citrate molecules into the cytoplasm was monitored in Counts Per Minutes (CPM) using a scintillation counter. The higher the number of radioactive citrate molecules counted, the higher the activity of the PMCT. This investigation is important because the selective inhibition of the PMCT may allow us to effectively regulate the influx of extracellular citrate into the cytoplasm and this may enable us to better understand metabolic disorders such as obesity and diabetes.
Evolutionary Trade-Offs in Bean Beetles
Beth DeFoe, Iman Shepard, Desire Uwera Nalukwago and Flavia Barbosa, Department of Biology, Lake Forest College, Lake Forest, IL 60045
Trade-offs in response to differential resource allocation tend to present as negatively correlated traits, but little is known about underlying developmental mechanisms. Bean beetles exhibit phenotypic plasticity in response to their larval environment, developing into a dispersal morph under high larval density and a non-dispersal morph under low density. There is a trade-off between dispersal and reproduction in the morphs, where dispersal individuals have large wings and small testes, and vice-versa. We investigate the possible role of juvenile hormone (JH) in the mechanism for this trade-off since JH plays a pivotal role in wing development and sexual maturation in other insect species. We treated beans with different concentrations of JH and allowed beetles to develop under controlled density conditions, then measured wing and gonad sizes. We predicted that higher JH titers lead to higher allocation to gonads and lower allocation to wings and vice-versa. The data for wing size supports our hypothesis and the data for gonads is still being analyzed.
Preparation of Novel Inhibitors of the Plasma Membrane Citrate Transporter (PMCT)
Mariia Denichenko ’22 , June Mayor, John Buolamwini, Ronald Kaplan, Shivaputra Patil
Biochemistry and Molecular Biology, Chicago Medical School and Pharmaceutical Sciences Department, College of Pharmacy, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
The plasma membrane citrate transporter (PMCT) is expressed predominantly in the liver of mammals where it functions in a variety of metabolic pathways, including as a key regulator of glycolysis. Recent studies have shown that loss or inhibition of PMCT activity diminishes hepatocellular carcinoma (HCC) cell growth by disrupting energy homeostasis. This suggests that PMCT can be a potential therapeutic target for liver cancer. Novel molecular frameworks and approaches must be identified to achieve progress in the area of drug discovery and development for PMCT inhibition for liver cancer. In continuation of our effort to discover new potent PMCT inhibitors, we recently identified a novel chromenopyridine ( SAP-165) as a lead PMCT inhibitor. In the present study, we prepared and characterized a focused set of chromenopyridines based on SAP-165. We will screen these new analogs for PMCT inhibition and anticancer activities in the near future.
Neural Basis of Age-dependent Decline in Decision Making and Motor Control
Megi Diasamidze ’23, Jaydeep Sambangi, and Eun Jung Hwang, Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
The rapidly growing elderly population faces a critical challenge of living independently due to reduced capacity to perform basic day-to-day tasks. Most of these tasks depend on sound decision-making and motor control, both of which are shown to deteriorate with age. Older adults are slower in responding to stimuli, less flexible to changes with stubborn bias, and less sensitive to their recent choice-outcome history to update their decision strategies (Samanez-Larking, 2015; Dully, 2018; Head, 2009). In addition, the movements of the elderly are slower, less coordinated, and more fractionated (Seidler, 2010). However, the neural underpinnings of these age-dependent behavioral changes remain largely unknown. To address this issue, we aim to examine age-dependent changes of the brain circuit in mice, focusing on the posterior parietal cortex, an area important for both decision-making and motor control.
First to characterize the behavioral phenotypes associated with aging in mice, we trained two groups of mice, young versus old (N=2 in each group), in the standardized international brain laboratory (IBL) decision-making task. In the IBL task, the head-fixed mouse learns to perform a visual decision-making task where they detect the presence of a visual stimulus on the screen and move a steering wheel using their forepaws. When the stimulus is to the right, the mouse must turn the wheel counterclockwise, and clockwise for the stimulus to the left. The mice were trained for up to 40 days. We found variable task learning capacities and decision strategies across 4 mice, but no significant differences between the two age groups due to the small sample size. Thus, we plan to train more mice in each group to acquire statistically conclusive results. Once age-dependent behavioral phenotypes are established, the neural correlates of those changes will be examined using in vivo two-photon imaging and optogenetics in mice performing the IBL task.
References
- Samanez-Larkin, G. R. & Knutson, B. Decision making in the ageing brain: changes in affective and motivational circuits. Nat. Rev. Neurosci. 16, 278–289 (2015).
- Dully, J., McGovern, D. P. & O’Connell, R. G. The impact of natural aging on computational and neural indices of perceptual decision making: A review. Behav. Brain Res. 355, 48–55 (2018).
- Head, D., Kennedy, K. M., Rodrigue, K. M. & Raz, N. Age-Differences in Perseveration: Cognitive and Neuroanatomical Mediators of Performance on the Wisconsin Card Sorting Test. Neuropsychologia 47, 1200–1203 (2009).
- Seidler, R. D. et al. Motor Control and Aging: Links to Age-Related Brain Structural, Functional, and Biochemical Effects. Neurosci. Biobehav. Rev. 34, 721–733 (2010).
Somatostatin (SOM) and calbindin (CB) expression pattern in the bed nucleus of the stria terminalis (BNST) in male rats
Andrew Forrest, Valentina Olivera, Susan Olson, Joanna Dabrowska
Somatostatin (SOM), a neuropeptide, and calbindin (CB), a calcium binding protein, are known to be expressed by neurons in some regions of the brains of rats such as in the central amygdala and the bad nucleus of the stria terminalis (BNST). The expression patterns of SOM and CB in the BNST have not been precisely characterized. The purpose of this study was to try to identify neuronal subpopulations in regions of the BNST that express SOM, CB, or SOM+CB. The expression patterns were visualized in coronally cut brain tissue slices 50µm thick from two rats, ranging from bregma 0.12mm to bregma -0.70mm, using immunofluorescence and subsequent fluorescent microscopy for imaging. These rats were infused with colchicine into cerebral ventricles to prevent peptide transport to nerve terminals and to visualize SOM-producing cell bodies in the BNST. Fluorescent images were taken with 4x, 10x, and 20x objectives. We found diffuse SOM and CB expression throughout many regions of the BNST. Some regions showed patterns of localized high expression consistent throughout the slices. In the anterior BNST (bregma 0.00mm to -0.30mm), SOM expressing neurons were found most in the oval BNST (ovBNST) and dorsolateral BNST (dlBNST), and CB expressing neurons were found most in the lateral BNST (latBNST), juxtacapsular BNST (jxtBNST), and ventral part of the ventral BNST (venBNST). In the posterior BNST (bregma -0.30mm to bregma -0.70mm), CB expression was high throughout most regions and less localized, and SOM expressing neurons were found most in the anteromedial BNST (amBNST) and dlBNST. SOM+CB co-expressing neurons were found most in the amBNST, venBNST, dorsal dlBNST, and latBNST. This characterization of SOM and CB expression will hopefully help to improve the characterization of the diverse subpopulations of neurons in the BNST and ultimately help researchers understand how the BNST modulates fear and anxiety-like behaviors.
Do female waxmoths benefit from mating with more attractive males?
Dariana Gomez ‘22 and Flavia Barbosa, Biology Department, Lake Forest College, Lake Forest, IL 60045
Male waxmoths produce signals to attract female mates: an ultrasonic call made up of a series of pulses. Females find signals with higher pulse rates more attractive, but it is not known whether females benefit from mating with more attractive males. We hypothesize that females benefit from mating with attractive males by: (1) having more offspring, (2) having more attractive male offspring, (3) having more fecund (larger) female offspring, and (4) producing offspring with a male-biased sex ratio. We tested this hypothesis by mating females with a male from one of two categories: attractive (fast pulse rates) or unattractive (slow pulse rates). We allowed those females to lay eggs and the eggs to develop to adults. Our next step is to compare the number, mass and sex ratio of the offspring from the two categories. Additionally, we recorded the mating calls of the male offspring, which we will later analyze. We expect that attractive males will produce more offspring, with more attractive males and more fecund females.
Insight into Parkinson’s Disease From a Yeast Model: How Three New Alpha-Synuclein Mutants May Cause Disease
Amanda Grassel ‘23, Fede Bertolotti ‘24, Carris Borland ‘21, Ryan Osselborn ‘23, Tracey Nassuna ‘23, Bryce Zabat ‘24, and Dr. Shubhik DebBurman, Neuroscience Program, Lake Forest College, Lake Forest IL 60045
Parkinson’s Disease (PD) is a fatal and incurable neurodegenerative disorder linked to the loss of dopaminergic neurons in the midbrain. A key pathological marker of PD is the presence of Lewy bodies, which are composed of misfolded α-synuclein protein. α-Synuclein is a highly post-translationally modified protein in both healthy and diseased states. Modifications on it include phosphorylation, nitration, SUMOylation, acetylation, and glycation. Regulation by lipids is also suggested to modify its toxicity. The toxicity of wildtype α-synuclein and six well-known mutant versions linked with familial PD (A30P, E46K, H50Q, G51D, A53T, A53E) is well-modeled in budding yeast systems. In contrast, the toxicity mechanisms of three newer PD-linked α-synuclein mutants (A18T, A29S, and A53V) is poorly understood; particularly, the impact of post-translational modifications and lipid homeostasis on their toxicity is unknown. Using our lab’s budding yeast model of PD, we investigated the toxicity potential of these three new mutants by assessing the impact of the mutations on yeast growth and α-synuclein localization in various yeast strains. We report that: 1) All three mutants are toxic to yeast, but to different degrees and, surprisingly, less than wild-type α-synuclein; 2) Yeast strains with altered triglycerides reduce α-synuclein toxicity; 3) Yeasts strains with enhanced acetylation or reduced glycation environments rescue α-synuclein toxicity; 4) and enhanced SUMOylation is protective against α-synuclein toxicity; 5) and, finally, yeasts strains deleted for specific PD-associated genes differentially affect α-synuclein toxicity. This study expands the evaluation of genetic α-synuclein mutants linked with PD in yeast models and supports the relevance of covalent modifications, lipid homeostasis, and PD-associated genes on α-synuclein toxicity.
The Role of Lymphocyte Cytosolic Protein 1 in a Mycobacterium Marinum Infection
Beau Grimes ‘24, Ceylin Sahin ‘24, William H. Conrad, Department of Biochemistry and Molecular Biology, Lake Forest College, Lake Forest IL 60045
Mycobacterium tuberculosis is an issue worldwide with multidrug-resistant forms becoming prevalent due to the lack of effective treatments. The goal of this project is to identify if there are host genes that affect the disease outcome. We decided to study the influence of the Lymphocyte Cytosolic Protein 1 (LCP1) gene in zebrafish larvae infected with mycobacterium marinum. To understand the immune response in the fish we observed the bacterial burden in fish that had LCP1 (heterozygotes) and in fish that did not (knockout mutants). M. marinum was injected into the caudal vein of the zebrafish larvae and the fish were infected. Once the fish were fixed and euthanized, images of the bacterial infection were taken using a fluorescent microscope. The bacteria was tagged with tdTomato, a red fluorescent protein which allows for the bacteria to glow red under the microscope. The images were then analyzed, and the bacterial burden was quantified using ImageJ to count the number of glowing pixels. Following the imaging of the infected larvae, the fish were genotyped. The DNA from the larvae was extracted through a hotSHOT PCR protocol, then LCP1 Exon 2 was amplified through PCR amplification. The PCR product was then cut with the Bsl-I enzyme to show where the gene was expressed, gel electrophoresis was then run to analyze where the Bsl-I cut and identify whether the fish was a heterozygote or knockout mutant. We then matched the suitable images of the fish to the genotype and found that fish with LCP1 may have a higher rate of infection. Understanding why fish with LCP1 have a higher bacterial burden could provide an insight to the role LCP1 plays in the human body’s immune response. The future directions of this project are to observe more fish in order to replicate the findings and to test other phenotypes including granuloma size, macrophage motility, and extracellular growth in order to have a better understanding of LCP1's role in the disease outcome.
Could research on the Murine Coronavirus help us in our efforts to combat the COVID-19 pandemic?
Jovana Jovanovska ‘23 and Dr. David Everly, Department of Microbiology and Immunology, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60045
The murine hepatitis virus (MHV) is a Betacoronavirus that infects mice. MHV, strain 1 infects mice and induces severe pneumonia with many of the immunological and pathological hallmarks of severe SARS-CoV and SARS-CoV-2 infections in humans. As such, research on MHV could possibly offer valuable insight into SARS-CoV-2 and lead to new strategies for treatment. The goal of the current project was to establish an in vitro culture system for MHV-1 production. In this research, MHV-1 was grown in mouse cells in culture and we formed plaque essays in order to isolate and purify the virus, as well as to determine the viral titer. We successfully grew MHV-1 and moreover, we performed a western blot to detect viral proteins, specifically the protein NSP9 which we expected to find produced in infected cells. Future research will quantitate the virus by real-time PCR and will utilize the virus in in vitro and in vivo infection models to evaluate novel coronavirus therapeutics. This research predominantly focused on the most efficient method of the production of the murine coronavirus which can be used for future research.
Differential enhancement of goal-tracking and sign-tracking by nicotine
Wambui Kahende ‘24, Kotryna Andriuskeviciute ‘24, Lael Medema ‘23, Nathaniel Kregar ’22, Leslie Gonzales ’21, and Dr. Jean-Marie Maddux, Psychology Department and Neuroscience Program, Lake Forest College, Lake Forest IL 60045
During Pavlovian conditioning, a conditioned stimulus (CS) predicts the delivery of an unconditioned stimulus (US). Two approach types, referred to as conditioned responses (CR), can be observed: towards the site of US delivery (goal-tracking) or towards the CS (sign-tracking). We compared the development of sign-tracking and goal-tracking with two different USs (ethanol or sucrose) and additionally, examined what effect nicotine had on this behavior. Male rats were given either ethanol and water or only water in their cages, as an exposure manipulation. Then, in conditioning chambers, the rats were presented with a lever that served as the CS that indicated upcoming delivery of the reward US. A behavioral control group received equal exposure to the CS and US, but in an explicitly unpaired fashion. Before each Pavlovian conditioning session, rats were injected with either nicotine or saline. Sucrose promoted faster conditioning than ethanol. However, this equalized with further training. Nicotine influenced both goal-tracking and sign-tracking, but in different ways. Nicotine increased goal-tracking only in the rats that were previously exposed to ethanol. It also increased sign-tracking later in training for both US (ethanol vs. sucrose) and exposure (ethanol vs. water) groups. This experiment identifies factors that affect Pavlovian conditioned responses.
Proteomic identification of the candidate target proteins of 15-deoxy-∆12,14-prostaglandin J2 in Kaposi’s sarcoma-associated herpesvirus (KSHV) infection.
Barry Khim ‘22, Saieshwar Chikoti, Daniel Flores, Sabrina Nasiri, Olivia Powrozek, and Neelam Sharma-Walia, Cancer Cell Biology, Immunology, and Infection, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, USA.
Kaposi’s sarcoma-associated herpesvirus (KSHV) is associated with causing cancers in humans, such as vascular tumor Kaposi’s sarcoma (KS) and B cell malignancy primary effusion lymphoma (PEL). Both latent and lytic replication phases are critical for the development of these malignancies. KSHV infection creates a unique inflammatory microenvironment conducive to its latency and survival in the host. KSHV utilizes polyunsaturated fatty acid called Arachidonic acid (AA) and its downstream metabolites and receptors to maintain their successful life cycle in the host (George Paul et al., 2010; Paul et al., 2011; Paul et al., 2013; Sharma-Walia et al., 2010; Sharma-Walia et al., 2014). AA metabolizes the pro-inflammatory cyclooxygenase (COX) pathway to produce prostaglandins (PGs). One of the downstream by-products of the AA pathway is 15-deoxy-∆12,14-PGJ2 (15d-PGJ2). 15d-PGJ2 is a natural anti-inflammatory agent with therapeutic properties. Our previous studies demonstrated that KSHV infection of primary endothelial cells downregulates the secretion of the anti-inflammatory 15d-PGJ2 in the host cells. 15d-PGJ2 can induce apoptosis in cancer cells (Colin et al., 2018). Therefore, we hypothesized that reintroducing 15d-PGJ2 back into KSHV infected cells will induce apoptosis. We treated uninfected and KSHV-infected cells with biotin-15d-PGJ2. We lysed cells, extracted proteins, and performed a pulled-down assay for biotin-15d-PGJ2 modified proteins using Neutravidin beads. Biotin-15d-PGJ2 modified proteins were electrophoresed on 4–20% SDS-PAGE gels, stained with Colloidal Coomassie Blue G-250, and bands were cut and sent for proteomic analysis. We performed a comprehensive proteomic analysis of 15d-PGJ2 candidate targets in KSHV infected cells compared to uninfected cells. We also observed the 15d-PGJ2 treatment for more prolonged time-induced death in the KSHV infected cells. In conclusion, our results provide a thorough understanding of cellular pathways modulated by 15d-PGJ2 during KSHV infection.
Counterfactual Thinking and Recency Effects in Causal Judgment
Aleksandra Kulesza, Karla Perez, Augustana Houcek, Paul Henne, Department of Philosophy, Lake Forest College, Lake Forest, IL 60045
People tend to judge more recent events, relative to earlier ones, as the cause of some particular outcome. For instance, people are more inclined to judge that the last basket, rather than the first, caused the team to win the basketball game. This recency effect, however, reverses in cases of overdetermination: people judge that earlier events, rather than more recent ones, caused the outcome when the event is individually sufficient but not individually necessary for the outcome. In five experiments ( N = 5507), we find evidence for the recency effect and the primacy effect for causal judgment. Traditionally, these effects have been a problem for counterfactual views of causal judgment. However, we argue that an extension of a recent counterfactual model of causal judgment explains both the recency and the primacy effect. In line with the predictions of our extended counterfactual model, we also find that, regardless of causal structure, people tend to imagine the counterfactual alternative to the more recent event rather than to the earlier one. Moreover, manipulating this tendency affects causal judgments in the ways predicted by this extended model: asking participants to imagine the counterfactual alternative to the earlier event weakens the interaction between recency and causal structure, and asking participants to imagine the counterfactual alternative to the more recent event strengthens the interaction between recency and causal structure. We discuss these results in relation to work on counterfactual thinking, causal modeling, and late-preemption.
The Generation of a Cloned SOX-4 Gene
Demetri Maglaras ’23 and Dr. Joseph Reynolds, Microbiology and Immunology Department, Rosalind Franklin University Medical School, North Chicago, IL 60064
DNA plasmids are complex molecular structures that are often used for carrying a transmitted gene of interest. The SOX-4 gene, a transcriptional factor gene found in homo sapiens, can be cloned into a DNA plasmid through a series of experiments and protocols. A common model for this type of experiment are murine CD4 + T cells given their ability to incorporate foreign DNA into the host genome. By cloning the SOX-4 coding sequence into an expression plasmid, we can then prepare for implementation of the cloned plasmid into an retroviral expression vector. A breakthrough connection between mice T-cells and the cloned DNA plasmid can be analyzed through this research. An intricate and detailed look into the process and buildup of these biological systems can be viewed with the data provided and with an immunological and microbiological lens.
The Link Between RyR2 Receptor and Alzheimer’s
Noah Mueller ’23, Sean Schrank, Sarah Mustaly, Grace E. Stutzmann Department of Neuroscience, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60045
Alzheimer's disease (AD) is a neurodegenerative disease that affects nearly 44 million people worldwide. As we age, we are more likely to get Alzheimer's disease from a combination of factors. Such as age, genetics, and lifestyle. There is still no clear distinction as to why someone will or will not develop Alzheimer's disease. With the new but highly controversial drug aducanumab hitting the market, there is potential hope to fight against this war on dementia. These anti-bodies mainly target amyloid-beta, responsible for forming the senile plaques observed in AD and the cognitively normal aging population. With the target of amyloid-beta within patients' brains, removing these blocks doesn't stop the progression of memory loss and death, which further questions the role of amyloid-beta as a specific target. With more understanding of Alzheimer's, we have uncovered the role of RyR2. This RyR2 receptor is responsible for the release of Calcium during excitation-contraction coupling. AD patients have shown increased calcium release within their cells, leading to neuronal death and contributing to memory loss. This project seeks to develop a high throughput drug discovery assay for compounds that regulate the RyR2 to regulate the critical process of Calcium homeostatic signaling as a way of targeting memory loss from a different angle. We will then discuss how other compounds affect the HEK cells and where to move from here.
Understanding Social Factors, Healthcare Recommendations and Follow Up Care in Berwyn, IL
Zahra Nadeem ‘22, Tamara Sher and HyeRim Ryu, Department of Psychology, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60045
Social factors such as race, gender, socioeconomic status, education and employment contribute towards health inequities people may face. These factors tend to affect the mindsets of residents within underserved areas and how they approach their medical needs. Berwyn is a primarily middle-class suburban city in Cook County, Illinois with a demographic makeup of Hispanic (36.2%), White (Hispanic) (25.9%), White (25.2%), Black or African American (6.39%), and Asian (2.69%) residents. The median age of Berwyn residents is 35.1 years. The Berwyn Health Department hosts health and fitness fairs to provide free health screenings to the suburban community. This allows the health department to understand the medical needs of the city and works to ensure that patients will follow up on the health recommendations that have been provided to them. The purpose of this project was to understand the primary demographic of Berwyn residents that attend these free health fairs. This project was completed as a preliminary step to an ongoing research project that will look at the effectiveness of the Berwyn Health Department health fairs and the psychology behind why this demographic of patients does not obtain the follow up care that is recommended to them. 129 patient files from the health fairs between the years of 2019 and 2021 were collected through the Berwyn Health Department to create a patient database including the age, gender, preferred language, marital status, number of children, whether a follow up was recommended, and PHQ-9 scores. Overall, it was found that the health fairs were mainly attended by a population with a median age of 61.7 years and required follow up care (53.4%) based on recommendations that were provided by physicians. 73.6% of attendees were female. The patient data collected indicates the majority of health and fitness fair attendees face a variety of healthcare needs, but are unable to acquire the follow up care they require.
Biosynthesis of O-acetyl-l-serine From an Acetyltransferase, dcsE
Zarina R. Najibi ‘22, Laurel Robbins ‘23, William H. Conrad, Department of Biochemistry and Molecular Biology, Lake Forest College, Lake Forest IL 60045
Tuberculosis is a deadly respiratory disease caused by the bacteria Mycobacterium tuberculosis which does not currently have a fully effective vaccine or treatment. The goal of this project is to develop an effective prophylaxis for tuberculosis using mammalian cells to biosynthesize a current tuberculosis antibiotic, d-cycloserine (dCS). Overall, we have used two approaches to activate this biosynthetic pathway in mammalian cells. To examine the entire biosynthetic pathway, we transfected Chinese Hamster Ovarian cancer cells (CHO) with plasmids encoding all six dCS biosynthesis enzymes (dcsA-G) and lysed them to isolate total protein and test for synthetic capability. By this approach, the expression of the genes detected by fluorescence microscopy was low and the in-vitro dCS biosynthesis from lysates was not detected by HPLC. In the second approach, we optimized individual enzymes starting with first one in the pathway, dcsE, which converts L-serine to O-acetyl-L-serine. To focus on dcsE, we used human lung epithelial cancer cells (A549) and transfected cells with a higher concentration of DNA to express the enzyme. More dcsE expression was detected by fluorescence microscopy and a Western Blot was used to detect the presence of our GFP tagged dcsE protein. Understanding that A549 cells and single gene expression has been more effective at producing the dCS enzymes has added new insight to successfully reproduce this biosynthetic pathway in human cells. The future directions of this project are to purify dcsE from crude lysate samples and use a kinetic analysis to test the functionality of dcsE as an acetyltransferase and eventually use the crude lysate to biosynthesize O-acetyl-L-serine with dcsE.
Effect of sex differences on outcomes of traumatic brain injury
Maria Jose Orozco Fuentes ‘24, Otoha Tatami ‘24, Rebecca Delventhal, Ph.D, Department of Biology, Lake Forest College, Lake Forest, IL 60045
Traumatic brain injuries (TBI) are seen in diverse settings like car accidents and contact sports. Continuous exposure to closed-head TBIs leads to loss of neurological function and other bodily functions. Sex differences in TBI are not fully understood, therefore, we examined the effect of TBI on females and their fertility using Drosophila melanogaster as a model. Prior research showed that TBI led to high acute mortality, lifespan decline, metabolic dysfunction, and loss of locomotion in male flies, but females had not yet been tested. We hypothesized female fruit flies might respond differently and also investigated female reproductive function to explore the effects of TBI on metabolic function in females. TBI was delivered through a High Impact Trauma (HIT) device which consists of a spring attached to a wooden board on one end. A vial is attached to the loose end, then it is pulled back and released. We found that females have significantly higher mortality 24 hours post-injury than males. Surprisingly, there was no significant difference in female fertility between TBI and control flies. We suggest investigating specific characteristics of female physiology that contribute to their higher mortality, but normal fertility, following TBI , by genetic screening and behavioral assays.
All in the Family? Studying Toxicity Tendencies of α-, β-, and γ-Synuclein in a Yeast Model
Ryan Osselborn ’23, Tracey Nassuna, Bryce Zabat, Carris Borland, and Dr. Shubhik DebBurman, Neuroscience Program and Biology Department, Lake Forest College, Lake Forest, IL 60045
Synucleinopathies are a group neurodegenerative disorders that arise from the misfolding and aggregation of α-synuclein. The most well-known among them is Parkinson’s disease, which is linked with the aggregation of both wild-type or mutant forms of α-synuclein in midbrain dopamine neurons. α-Synuclein belongs to a larger family of proteins that include β- and γ-synuclein. Recently, a mutant form (P123H) of β-synuclein was shown to cause Dementia with Lewy Bodies (DLB), but whether β- and γ-synuclein contribute to neurodegeneration is still highly understudied compared to α-synuclein. Our lab was one of the earliest in the world to create yeast models to study α-synuclein’s pathological potential. In order to comparatively examine the cytotoxic and aggregation potential of α-, β-, and γ-synucleins, we sought to tag them (as well as the P123H-β-synuclein) with emGFP (Emerald Green Fluorescent Protein) and insert into a yeast-expression vector using a three-step sub-cloning process. In the first step, using Polymerase Chain Reaction (PCR), we amplified and sub-cloned each of these synuclein genes into an entry vector containing site-specific recombination sites. Secondly, a recombination reaction was performed between this entry vector and a destination vector that already contained the emGFP gene, allowing for tagging of emGFP at C-terminus ends of the synuclein genes. Lastly, we used PCR again to amplify these synuclein-emGFP fusion genes from the destination vector and sub-cloned them into the the pYES2.1 vector, which would allow us to express and study synucleins in budding yeast. Here, we report successful completion of this three-step process and are ready to comparatively evaluate the pathological potential of these synucleins in our yeast-based model system.
Investigating effects of abstract-concrete effect on causal judgements
Wiktoria Pedryc & Dr. Paul Henne, Department of Philosophy, Lake Forest College, Lake Forest, IL 60045
People tend to think that agents are more morally responsible in concretely phrased scenarios relative to abstractly phrased ones. We investigated whether a similar abstract-concrete effect occurs for causal judgements and if counterfactual thinking—i.e., tendency to imagine probable alternatives to events—is a potential mechanism for this effect. Since counterfactuals seem easier to imagine for concrete scenarios relative to abstract ones, we predicted that people would have stronger causal judgements in concrete scenarios and weaker causal judgements in abstract ones. In Study 1 ( N=127), we presented participants with either abstract or concrete condition of a causal scenario, and we asked about causality of each factor contributing to the outcome. We found no evidence of a difference in causal judgements. That is, we found no evidence for abstract-concrete effect in causal judgements. We explore the philosophical implications of a lack of an abstract-concrete effect in causal judgements.
Modelling Rh Bis-(Diazaphospholane) Ligands in Hydroformylation Catalytic Cycle
Nhu Quach’22 and Dawn Wiser, Chemistry Department, Lake Forest College, Lake Forest, IL 60045
Hydroformylation catalytic cycle is a chain of reactions converting alkenes to aldehydes, which involves the help of transition metal catalysts. This cycle is universal in the pharmaceutical and fragrance industry, where aldehydes with specific stereochemistry are extensively used. (1) The goal of this research is to study the influence of the Rh diazaphospholanes catalysts structures on the stereoselectivity and enantioselectivity of the aldehydes. This goal is achievable by using computational software (Gaussian 09 and Herb) to examine their possible products’ energies and structures. The research focuses on two (S, S)-3,4-bis(diazaphospholane) ligands (BDP1 and BDP2). The understanding from this study will contribute to design a more efficient and selective Rh catalyst for this widely used hydroformylation cycle.
- Whiteker, G. T., & Cobley, C. J. (2012, February 10). Applications of Rhodium-Catalyzed Hydroformylation in the Pharmaceutical, Agrochemical, and Fragrance Industries. Springer Link. Retrieved October 7, 2021, from https://link.springer.com/chapter/10.1007/3418_2011_28.
The Effect of Hypoxia on HIV-1 Gene Expression and Replication
Serenah Quiroga, Sahar Rezaei, Khalid Timani, and Johnny He
Latent reservoirs are a large contributor to our inability to establish a cure for the human immunodeficiency virus (HIV-1) as it is difficult to eradicate. However, these reservoirs can be utilized to understand the regulating factors of HIV-1 replication and reactivation that occur and help us expand our approach on future strategic controls and potential eradication of the virus. Expanding research is required in order to understand the physiological factors that play a role in HIV-1 preservation in the host cells. One of the significant physiological factors is the varying oxygen concentration levels in our bodies. For instance, lymphoid tissues obtain 1% O 2 while CD4 + T cells in arterial blood remain at a 13% O 2 concentration. Due to the inconsistency of oxygen concentration levels within our bodies, viruses such as HIV-1 have adapted accordingly in order to continue replicating and survive in the host. Most studies prior that explored HIV-1 replication and infection have only focused on normal oxygen conditions (21% O 2). In the present study, we investigated the effects of hypoxia on HIV-1 gene expression and replication in HIV-1 (Gagi) infected CD4 + T cells and ACH-2 latent cells. We utilized a variety of methods including Western Blotting analysis, RTase activity assay, and Immunofluorescence Imaging. Our results indicated that HIV-1 infected cells standing as the untreated control showed a decrease of viral replication in the 1% O2 condition compared to 21% O 2 condition after 72 hours. Additionally, ACH-2 latent cells that were untreated and those treated with TNF-α showed a reduction in intracellular Gag gene expression in hypoxia conditions after 72 hours compared to their normoxic counterparts. These results suggest that the level of oxygen in a cellular environment can have an effect on viral replication and HIV-1 gene expression in our bodies, which may also indicate a key role in latency development.
Police Expertise in Use-of-Force Rapid Decision-Making
Sophie Rasof, Isabel Krupica, Dr. Vivian Ta, Psychology Department, Lake Forest College, Lake Forest, IL 60045
Use-of-force decisions among police officers typically occur under stressful and fast-paced conditions. Because judgment and decision-making from more experienced individuals tend to be more effective, efficient, and accurate compared to less experienced individuals, researchers have sought to understand the specific skills involved in the selection of appropriate uses-of-force among expert officers compared to novice officers. In the current study, we examined how a sample of expert ( n = 42) and novice ( n = 36) officers differ in their decisions in use-of-force scenarios. Officers observed a series of body-worn camera footage of real-world police-citizen encounters across the US that were temporally occluded at several decision points. At these decision points, officers were prompted to describe the course of action they would take in the next few seconds if they were the officer on scene. Responses were coded for behaviors ( n = 19) that officers indicated they would engage in. A series of linear mixed-effects models revealed that expert and novice officers differed on their decisions to (1) pursue a suspect; (2) deescalate the situation, and (3) subject themselves into a particular scenario. Practical and research implications for expert performance in use-of-force training and decision-making are discussed.
Study of Rh(111)/O Systems
Emma Remish ‘221, Weronika Walkosz 1, Juan Garcia 2, Hakim Iddir 2, and Daniel Killelea 3
1Department of Physics, Lake Forest College, Lake Forest, IL 60045
2Argonne National Laboratory, Chemical Sciences and Engineering Division, Lemont, IL 60439
3Department of Chemistry, Loyola University Chicago, Chicago, IL 60660
Various properties of metal surfaces can be altered by interactions with oxygen, which can reside on the metal surfaces as well as in the subsurface region. It has been shown that subsurface oxygen greatly affects the reactivity of catalytic surfaces and is a precursor for oxide formation [1-4]. Density Functional Theory allows us to investigate various structures of oxygen on different surfaces, including Rh(111), and thus study the competition between oxide formation on Rh(111) surface and the dissolution of O into Rh to form subsurface oxygen.
We report result of a systematic study of O adsorption on Rh(111) surface and the subsurface performed using the Vienna Ab initio Simulation Package (VASP). We found that surface O prefers to bind at the fcc site of Rh(111) at a coverage of 0.25 ML, but the binding energy decreases with increasing O coverage. The energy barrier for O diffusion on the surface of Rh(111) from the hcp to the fcc sites is rather small, indicating that O is very mobile on Rh(111). Further we found that the subsurface oxygen’s preferred binding site is the tetra I site with three Rh atoms above it and one below. However, the calculated binding energy is significantly smaller than the O binding energy at the surface fcc site due to the local distortions caused by the insertion of subsurface O. Lastly, we considered arrangements involving structures with combined surface and subsurface O atoms to identify which structure are energetically favorable. The obtained results are expected to provide new knowledge about the influence of O on Rh, furthering our understanding of the chemistry of transition metal surfaces and gauging their importance in heterogeneously catalyzed reactions.
[1] Rose, M. K.; Borg, A.; Mitsui, T.; Ogletree, D. F.; Salmeron, M. J. Chem. Phys. 2001, 115, 10927-10934.
[2] Monine, M.; Pismen, L.; Bar, M.; Or-Guil, M. J. Chem. Phys. 2002, 117, 4473-4478.
[3] Xu, Y.; Greeley, J.; Mavrikakis, M. J. Am. Chem. Soc. 2005, 127, 12823-12827.
[4] Rotermund, H. H.; Pollmann, M.; Kevrekidis, I. G.Chaos 2002, 12, 157-163.
Effect of severity and repetition of traumatic brain injury on Drosophila melanogaster
Neal Schaffer ‘22, Kamden T. Kuklinski ‘23, Hannah M. Turnage ‘23, Maria Jose Orozco Fuentes ‘24, Otoha Tatami ‘24, Dr. Rebecca Delventhal, Department of Biology, Lake Forest College, Lake Forest, IL 60045
Traumatic brain injury (TBI) affects many individuals following a sudden impact on the head. Despite an extensive body of research that addresses the various effects on the brain following a TBI, it is still poorly understood how the severity and repetition of TBI affects short- and long-term brain health. To address this, we used Drosophila melanogaster (the common fruit fly) as a model organism to compare the outcomes of several multi-day TBIs of varying severity to a single, severe TBI. We examined differences in acute mortality, lifespan, and locomotor performance of the flies following the injury. Acute death in the multi-day paradigms was lower than in the single-day, yet when measuring long-term mortality, multi-day paradigms resulted in a decreased lifespan equivalent to or greater than the single-day injury. When measuring locomotor performance, one of the multi-day injury paradigms resulted in worse locomotor function over time compared to the single day injury. These findings suggest that there are differential outcomes not only based on the severity of the injury, but also on the temporal accumulation of an injury.
Effects of nicotine on the locomotion of wild-type and acetylcholine receptor mutants in Caenorhabditis elegans
Katrina Topacio ’22 and Hongkyun Kim, Department of Cell Biology and Anatomy, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60045
Nicotine is a highly addictive substance that causes many harmful effects, including cancer. It binds to a particular type of acetylcholine receptor called the nicotinic acetylcholine receptor (nAChR) and acts as an agonist to acetylcholine receptors. Caenorhabditis elegans is a model organism that shares many of the same nAChRs as humans, therefore making them an ideal model to study. Here, we examine the direct and indirect effects of varying concentrations of 1 M nicotine (100 μM, 200 μM, 10 mM, 20 mM) on the locomotion of wild-type (N2) and acetylcholine receptor mutant ( acr-16, unc-38 and acr-16;unc-38) worms. CRISPR/Cas9 was also used to change one amino acid within the nAChR of the acr-16 gene to create a mutation that alters receptor open kinetics. Two types of assays (swimming assay and nicotine plates) were performed in these animals. Overall, we found that 20 mM of nicotine inhibited locomotion for all worm types during swimming assays. The addition of 10 mM of nicotine resulted in an initial decrease in location for the N2 worms, but there was no notable difference for the acr-16 worms. For the nicotine plates, there was a notable decrease in average velocity for the N2 worms and both treatment groups over time. The results demonstrated that a high dose of nicotine was required to affect movement in acr-16 worms. The next step would be to study the acr-16 mutant and to attempt to lower the dose necessary for nicotine to take effect when exposed to nAChRs.
Creating the Religion, Biology, and Public Health Course at Lake Forest College
Sophia Timm ‘24, Elya Gasparyan ‘24, and Stanzin Zasal ‘24, Religion Department, Lake Forest College, Lake Forest Il, 60045
The present research prepared materials for a new class at Lake Forest College titled Religion, Biology, and Public Health (RELG 239). Exploring religion as a social determinant of public health, the class examines how the religious backgrounds that people come from influence the way that they see the world and interact with different social structures. When people who subscribe to certain religious agendas are put in positions of governmental power, their backgrounds influence the legislatures which they set into place. In this research, we prepared presentations of case studies on the AIDS epidemic and Physician Assisted Suicide. Further, we analyzed primary and secondary sources to be used in class and created assessments to judge students’ performance. From the synthesis of the information we gathered, we created course materials that include timely discussions of the intersection of Biology, Religion, and Public Health
What Does It Mean If We Are Dating?
Xinyu Wang, Annie Keller, Esther DeCero, Katelyn Kauth, Catherine E. Miller, Amelie Claire Motzer, Wiktoria M. Pedryc, Imani Downer, Dr. Vivian Ta, Psychology Department, Lake Forest College, Lake Forest, IL 60045
We explored modern lay definitions of dating and how they vary across gender and age. In Study 1 ( N=330), participants described how they personally define dating. Seven themes emerged and were associated with exclusivity, seriousness, intimacy, spending time together, recognition, assessment, and romantic interest. In Study 2 ( N=266), participants provided demographic information and rated the degree to which each theme represented their own definition of dating. Women were more likely to define dating in terms of having romantic interest in someone and only seeing one person compared to men. Compared to younger adults, older adults were less likely to view dating as an exclusive, serious relationship in which partners spend time and develop emotional intimacy with one another. Older adults were also less likely to agree that dating involves all partners mutually classifying their involvement with one another as “dating”. Our results make distinctions between dating and similar types of relationships, and highlight an aspect of dating that has not been addressed in previous work. We discuss the mismatch between modern definitions of dating and strategies used by researchers to operationally define dating and recommend usage of multidimensional measures of dating that encompass these seven themes in future research.
Creating Synthetic Templates to Determine the Telomeric End Nucleotide
Meklit Yimenu ‘23, Jessica Day ‘22, Graeme Witte ‘22, Natalie Kamau ‘24, Allison Akins ‘22, and Karen Kirk Biology Department, Lake Forest College, Lake Forest, IL 60045
Telomeres are DNA sequences at the ends of chromosomes that are made up of multiple repeats of the same sequence. The telomeric repeat of human DNA is TTAGGG, which is also the repeat sequence in the fungus, Aspergillus nidulans. The length of both human and A. nidulans telomeres is known and previous experiments have shown that some nucleotides occur more than others at the end of human telomeric sequences. However, the preferred end of the A. nidulans telomeres has not been explored and the end nucleotides of both strands of A. nidulans telomeres are not known. As such, we designed a quantitative PCR (qPCR) assay to determine the end nucleotide of A. nidulans telomeres. To validate the results of this assay and to have a controlled system with which to compare our results, we designed a synthetic positive control system. This artificial control system consists of six templates, each containing a different order of the six nucleotide telomeric repeat. The qPCR reactions with these templates will be used to determine the specificity of our assay and these results will then be used as a reference to interpret the results of qPCR assays conducted with A. nidulans genomic DNA. This will enable us to determine the frequency with which each ending occurs in the A. nidulans DNA. Determining the final nucleotide is important for further characterization of the mechanism by which the telomerase holoenzyme maintains and extends telomeres.