Proportional-Derivative Control of Cortisol for Treatment of PTSD.

Mental illnesses, such as depression or post-traumatic stress disorder (PTSD), often impact an individual's physiological reaction to stress via their cortisol response. We examine the regulation of cortisol within the hypothalamic-pituitary-adrenal (HPA) axis as a dynamic biosystem. We investigate the difference between the cortisol regulation of people with PTSD and healthy controls. Additionally, we investigate models for potential therapies based on proportional-derivative (PD) control to normalize and improve the stress response of those with PTSD. Such a design may be relevant to improving the treatment of PTSD, as current medical interventions are frequently imprecise and may result in unwanted side effects. The use of a PD controller in administration of hormone therapy, in contrast, can be highly measurable and patient specific.Clinical Relevance- This paper offers an approach to treating post-traumatic stress disorder (PTSD) via stabilizing an individual's endocrinal regulation as a potential future alternative to current pharmaceutical practices.

Scavenging amyloid oligomers from neurons with silica nanobowls: Implications for amyloid diseases.

Amyloid-ß (Aß) oligomers are toxic species implicated in Alzheimer's disease (AD). The prevailing hypothesis implicates a major role of membrane-associated amyloid oligomers in AD pathology. Our silica nanobowls (NB) coated with lipid-polymer have submicromolar affinity for Aß binding. We demonstrate that NB scavenges distinct fractions of Aßs in a time-resolved manner from amyloid precursor protein-null neuronal cells after incubation with Aß. At short incubation times in cell culture, NB-Aß seeds have aggregation kinetics resembling that of extracellular fraction of Aß, whereas at longer incubation times, NB-Aß seeds scavenge membrane-associated Aß. Aß aggregates can be eluted from NB surfaces by mechanical agitation and appear to retain their aggregation driving domains as seen in seeding aggregation experiments. These results demonstrate that the NB system can be used for time-resolved separation of toxic Aß species from biological samples for characterization and in diagnostics. Scavenging membrane-associated amyloids using lipid-functionalized NB without chemical manipulation has wide applications in the diagnosis and therapy of AD and other neurodegenerative diseases, cancer, and cardiovascular conditions.