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Model systems approaches search for commonality in patterns underlying biological diversity and complexity led by common evolutionary paths. The success of the approach does not rest on the species chosen but on the scalability of the model and methods used to develop the model and engage research. Fine-tuning approaches to improve coral cell cultures will provide a robust platform for studying symbiosis breakdown, the calcification mechanism and its disruption, protein interactions, micronutrient transport/exchange, and the toxicity of nanoparticles, among other key biological aspects, with the added advantage of minimizing the ethical conundrum of repeated testing on ecologically threatened organisms. The work presented here aimed to lay the foundation towards development of effective methods to sort and culture reef-building coral cells with the ultimate goal of obtaining immortal cell lines for the study of bleaching, disease and toxicity at the cellular and polyp levels. To achieve this objective, the team conducted a thorough review and tested the available methods (i.e. cell dissociation, isolation, sorting, attachment and proliferation). The most effective and reproducible techniques were combined to consolidate culture methods and generate uncontaminated coral cell cultures for ~7 days (10 days maximum). The tests were conducted on scleractinian corals Pocillopora acuta of the same genotype to harmonize results and reduce variation linked to genetic diversity. The development of cell separation and identification methods in conjunction with further investigations into coral cell-type specific metabolic requirements will allow us to tailor growth media for optimized monocultures as a tool for studying essential reef-building coral traits such as symbiosis, wound healing and calcification at multiple scales.

Thermal Escher sensors are pixel-efficient lensless diffractive computational thermal imagers whose point-spread functions contain sharp transitions and effectively wrap around pixel array borders. These compact devices support high-resolution sensing and imaging.

The process of chemical neurotransmission involves a dynamic balance between signal initiation and/or signal termination. Psychostimulants have long been known as drugs that alter both of these processes associated with monoaminergic neurotransmission. Specifically, it has been known for many years that cocaine and methylphenidate prevent signal termination by inhibition of dopamine (DA) and serotonin (5HT) transporters (DAT and SERT, respectively). In addition, amphetamine analogs such as amphetamine (AMPH), methamphetamine (METH), and methylenedioxymethamphetamine (MDMA), enhance signal initiation by causing release of DA and/or 5HT. More recently it has been discovered that psycho stimulants alter additional processes. In particular, amphetamines reduce the transport activity of DAT and/or SERT. The first part of this dissertation is focused on elucidating the mechanism whereby amphetamines decrease monoamine transport function. Results reveal that the METH- and MDMA-induced decrease in DAT and SERT activity can be prevented with NPC15437, a protein kinase C inhibitor. In addition, a novel mechanism of transporter regulation was discovered that involves the lipid second messenger, ceramide. The ceramide-induced alterations in monoamine transporter function appear distinct from those of METH, uncovering an interesting phenomenon: C2-ceramide reduces DA transported through the DAT while concurrently increasing the transport of 5HT through the DAT. This dissertation also contains the first evidence that psychostimulants alter the trafficking of synaptic vesicles. Cocaine and methylphenidate (drugs that are not neurotoxic to DA neurons) appear to influence the trafficking of vesicles in a manner somewhat opposite to the amphetamines (drugs which are neurotoxic to DA neurons). Results demonstrate that these vesicle trafficking events are specific for monoamine containing vesicles and occur at high as well as low, clinically relevant, doses. Data presented in this dissertation help to increase our understanding of neurotransmission and psychostimulant-induced alterations in neurotransmission. These data may be useful for understanding and treating various related neurological disorders.