In order to effectively study the interactions that occur between neurons found in the brain, spatially and after an extended period of time, it is necessary to have reliable, repeatable studies. This is difficult to accomplish through conventional two-dimensional cell culture techniques, but three dimensional (3D) elastomer foams satisfy these criteria. Here we present a platform to study complex neuronal networks for extended periods in vitro. Elastomer foams were constructed with pore sizes ranging from 150μm to 400μm with 40μm secondary pores which allowed human neuroblastoma cells (SH-SY5Y) to adhere and interact with the foam and be sustained for long term studies, over 60 days. Through confocal imaging, it is shown that neuroblastoma cells mature while extending neurites and extensions while grown on the elastomer. Being able to sustain neurons for this length of time in 3D arrangements allows for a better representation of the interactions that occur in 3D tissues, making this method applicable for studying neurodegenerative disease states.

We analyzed the behavior of two separate impala (Aepyceros melampus) herds within the Wits Rural facility in Limpopo Province, South Africa. We hypothesized that fawns would spend less time vigilant than the adults and would spend more time in social interactions and foraging. We also hypothesized that the alpha (dominant) male would spend a greater portion of his time vigilant than the adult females, who would spend a greater amount of time foraging. The two herds were separated by roughly 2 km in a lightly forested savanna biome. There were 20-40 individuals in each herd. Each herd consisted entirely of mothers and fawns with a single alpha male among the herd. Random individuals within the herds were selected and their behaviors were recorded from a distance every 15 seconds. Observations on individuals varied in duration from 5-30 minutes. Date, time of day and habitat were also recorded during each observance. Eleven standard behaviors were observed. These behaviors included: foraging, vigilance, nursing, fawn-tending, excretion, interactions with other individuals (notes of the interactions were made), other (notes of their behavior were made), individual became out of view, vocalizations, grooming, and bedding down.

Stress has been shown to induce adverse effects such as depression, heart disease, and hypertension (Roman et al., 2016, Aschbacher et al., 2016, Ojike et al., 2016). Following a stressful event there is an increase in circulating glucocorticoids, primarily cortisol in humans and corticosterone (CORT) in rodents. CORT is primarily controlled via the PVN, the major regulating structure in the hypothalamic-pituitary-adrenal axis (HPA axis, Ferguson et al., 2009). Normally, stressful stimuli causes activation of the PVN, triggering the release of CRH from the hypothalamus, subsequently causing the release of ACTH from the anterior pituitary gland, resulting in the production of CORT from the adrenal cortex that will negatively feedback to regulate its release.

When the HPA axis is dysregulated, CORT can become over secreted and result in depression-like behaviors (Goshen et al., 2008). However, the majority of research today uses superphysiological levels of CORT (10-15mg/kg CORT) to induce the depressive-like behavior in rats (Johnson et al., 2010). As a result, there are still discrepancies of whether the administration of superphysiological levels of CORT follows the same mechanism of stress exposure to induce depressive-like behaviors. To resolve this issue, we propose the superphysiological levels of CORT are only necessary when the circadian timing of the CORT administration is not adequately controlled.

This current work is a mechanistic study to determine whether we are able to activate the PVN and ultimately increase rat CORT levels though designer receptor exclusively activated by designer drugs (DREADD) technology. DREADDs have been used to control cellular activity in both a spatial and temporal manner to successfully analyze neural circuitry previously, and is used in this experiment to induce transcription of cellular receptors to mediate the cell response, allowing control over circulating CORT levels (American College of Neuropsychopharmacology, 2012). It is hypothesized that once the CNO ligand has been injected and binds with the DREADDs, the PVN will be activated and result in an increase of CORT.

Our original intention was to carry out a giving-up density experiment with three troops of Vervet monkeys Cercopithecus aethiops at the Wits Rural Research Facility in eastern South Africa. We placed 7 lidded buckets containing peanuts and wood blocks at different heights within, and distances away from, three marula treesSclerocyra birrea where separate troops foraged. The presence of the wood blocks mimicked the time and effort spent while naturally foraging, and the hole in the lid (6 cm) was smaller than the sizes of the wooden pieces (7 cm diameter). The amount of peanuts eaten from each bucket after a foraging period indicates that these were the more favorable feeding patches - where they felt the safest (lowest predation risk), and spent the most time foraging. We realized that the amount of natural, more easily accessible food sources to the monkeys was large because it was summer in South Africa. They had no interest in our buckets of peanuts while there was ample fresh food nearby. As a result, we switched tactics to observation-based data collection. We found the most visible troop and spent multiple days taking ethogram observations of as many individuals as possible. Every 15 seconds, the behavior of every individual in the sample was recorded. Behaviors such as vigilance, foraging, and interacting with peers and offspring were common. These ethogram samples suggest the comfort level of the troop in their environment, their apparent stress towards food source availability, and their perception of nearby predation risk.

Ongoing climate change and urbanization will continue to put pressure on diminishing freshwater resources. To combat these effects, water management policies need to be continually updated with the most current scientific information to reflect changes in types and amounts of pollutants and new knowledge about toxicity. For this analysis, we compared two metals: a well-studied pollutant (copper [Cu]) and emerging contaminant of concern (silver [Ag]). We assessed water quality criteria for these two metals from the United States, Australia and New Zealand, South Africa, Canada, and the European Union to determine the intent of these criteria and implementation strategies used in adoption practices. Additionally, we conducted standard chronic toxicology tests for silver and copper on the freshwater pond snail Lymnaea stagnalis to assess the level of effectiveness offered by each regulation in protecting ecological integrity. L. stagnalis were individually placed in 100 mL beakers of test solution (0–32 µg/L for both Cu and Ag) for a 28-day period with water changes every 4 days. Ten replicates were used per treatment to measure mortality and growth rates. Preliminary results suggest that Ag is more toxic than Cu. However, because Ag is a poorly studied contaminant, water quality criteria for Ag are typically older, more variable, or absent and thus may not offer protection in some jurisdictions.

An increasing number of feral and free-ranging cats roam the United States; the repercussions of which have become apparent to both the scientific community and caretaker community alike. Due to the steadily increasing population of feral and free-ranging cats in the United States and globally, research and caretaker interest about this issue is also increasing. However, the most effective control methods for these non-native predators is debated. Management decisions do not always rely on the best available science, partly because the science is inadequate for many issues related to feral and free-ranging cats. For example, estimates of immigration and emigration rates into and out of feral cat colonies is limited in the scientific literature. In a previous pilot study conducted in 2015, an attempt was made to add important empirical data to this debate through the investigation of immigration and emigration rates into and out of local feral and free-ranging cat colonies. Although the results of this small study were inconclusive, it became clear that these data were important and an expansion of the pilot study was warranted. As a follow-up to the previous study, a larger scale study will be conducted to add the data that is lacking to the discussion. In addition, education of the public is also critical; without it, we cannot create a collaborative environment within which we can identify common solutions and develop best strategies focused on reducing cat overpopulation.

Background: The reaction of NO with superoxide anion to form peroxynitrite has been implicated as a potential mechanism contributing to the limited NO bioavailability observed in diabetes. Furthermore, there is little evidence outlining the effects of intravenous anesthetic, propofol, on NO bioavailability in cardiomyocytes (CMs) isolated from diabetic mice. We hypothesized that propofol would act as a superoxide scavenger, thereby increasing NO bioavailability.

Methods: For NO, superoxide and peroxynitrite measurements, freshly isolated control and diabetic CMs were incubated in the presence or absence of propofol with NO, superoxide (DHE) or peroxynitrite (HKG) fluorescent probes. Fluorescence was measured using either fluorescence microscopy or a fluorescent microplate reader.

Results: NO fluorescence was decreased 34 ± 8% in diabetic CMs as compared to control. Superoxide-dismutase polyethylene-glycol (catalyzes superoxide; PEG-SOD) increased fluorescence 33 ± 6% in diabetic CMs while it had no effect on the control. Intra-nuclear DHE fluorescence was increased 41 ± 9% in diabetic CMs compared to controls. Propofol increased NO bioavailability 25 ± 7%, 32 ± 5% and 41 ± 6%, respectively, in diabetic CMs while having no effect in controls. Moreover, propofol decreased superoxide 24 ± 8% and peroxynitrite 27 ± 3% in diabetic CMs while having no effect in controls.

Conclusions: Our results indicate that NO levels are decreased in diabetic CMs due to its reaction with elevated superoxide levels, producing excessive amounts of peroxynitrite. Clinically relevant concentrations of propofol increased NO bioavailability and this is, in part, mediated by the propofol-induced decrease in superoxide in diabetic CMs.

Alzheimer’s disease (AD) is one of the most prevalent neurodegenerative diseases, affecting over 5 million people in the United States. Previous work in our laboratory demonstrates the importance of luteinizing hormone (LH) signaling in learning and memory and AD. Though we have also previously demonstrated that LH is present in the brain, the neuroanatomical and cellular localization of LH has not been determined. To address this, we carried out immunofluorescence of free floating coronal sections to determine in which regions of the brain and cellular types LH are located. Immunoreactivity of LH is observed in limbic system areas associated with emotion as well as learning and memory and several midbrain motor nuclei. Importantly, high expression of LH is visualized in the retrosplenial cingulate cortex and other areas of critical importance in AD. Furthermore, we have also identified the expression of LH and GAD67 to be neuronally co-localized and the expression of LH to be localized to inhibitory neurons. Together our findings demonstrate that LH localization and the co-localization of LH and GAD67 are in areas and cell types important in regulating cognitive and emotional circuits. Thus, our data further supports a direct role of this hormone in cognition.

Moth Species Diversity and Abundance Across Different Habitat Types in South Africa Savanna

Ruthann Antolik, Brettney Lamp

We recorded moth species richness and diversity at the Wits Rural Facility in the Limpopo province, South Africa. It was conducted from January 5th to January 10th. The purpose of this study was to observe whether moth community composition changed across three different habitats within the South African savanna biome. Those habitats were the ecotone, our campsite, which represented a disturbed habitat, and woodland. We compared these three habitats because each one is different enough to foster different morphotypes, but they are also close enough to have an overlap in morphotypes. We expected the disturbed habitat to have the highest abundance and richness because it is very well lit, attracting many moths. Moth traps were set within each habitat by hanging white sheets and placing a lantern in their proximity to attract moths. We set three replicates in each habitat. The moths were collected the following morning between 4:30 AM and 5:30 AM. The collection was done for four days. Collected moths were placed in a “kill jar”, a container with acetone in the lid's compartment to collect moths without damaging their wings. We categorized 37 moth morphotypes and counted their relative abundance. Overall, there were more morphotypes collected in the disturbed habitat, as well as more moths collected overall. Our results suggest a very limited overlap in morphotypes across different habitats.