Follow

• 

  Tissue-Engineered Delivery of Manuka Honey

  Calista Adler, Karina Mitchell, Sreejith Panicker, and Katherine R. Hixon

  Manuka Honey (MH) contains the Unique Manuka Honey Factor (UMF), which is directly correlated to honey’s antibacterial efficiency and has a wide range of wound healing properties. In more recent years, MH has been incorporated into tissue-engineering scaffolds including cryogels, hydrogels, electrospun fibers, and electrosprayed nanoparticles. Tissue-engineered scaffolds can serve as alternative vehicles for delivery as compared to traditional wound dressings.The project objective was to investigate which of the four scaffold types can successfully incorporate MH (0, 1, 5, 10%) while retaining original parameters. We hypothesize that cryogels offer the best vehicle of delivery of MH because of increased durability (mechanical properties) compared to that of hydrogels and electrospun/electrosprayed scaffolds.

• 

  Microglia clearance of single dying oligodendrocytes is mediated by Cx3cr1

  Hiba Ali, Genaro E. Olveda, and Robert Hill

  Myelin sheath, generated by oligodendrocytes, plays a vital role in ensheathing axons for efficient neural communication. Degeneration of myelin sheath is associated with several neurodegenerative diseases and aging. When myelin sheaths are damaged or degenerated, the resulting debris needs to be efficiently cleared to allow for regeneration and remyelination. The causes of myelin degeneration in various diseases vary, but the inability to effectively remove the myelin debris contributes to disease development and prevents tissue healing. Microglia are highly specialized phagocytic cells capable of recognizing and engulfing myelin debris. The Cx3cr1 gene, which is primarily expressed on microglial cells, plays a significant role in the process of debris clearance. To investigate the role of Cx3cr1 on clearance of single dying oligodendrocytes, we used a technique called 2Phatal. Longitudinal in vivo imaging revealed that microglia lacking the CX3CR1 receptor took on average 3 days longer to clear the targeted oligodendrocytes compared to controls. This suggests that Cx3cr1 plays a critical role in facilitating the rapid and efficient removal of dying oligodendrocytes.

• 

  Dynamic Nuclear Polarization in Diamond

  Catherine Chu and Chandrasekhar Ramanathan

  Dynamic Nuclear Polarization (DNP) is a technique used to amplify the signal in Nuclear Magnetic Resonance (NMR). Magnetic resonance is a phenomenon that occurs when spins in a magnetic field are excited by a resonant electromagnetic field. In our experiment, we apply a radio-frequency (RF pulse) to the nucleus of a sample at the same frequency that the nuclear spin is precessing.

• 

  Exploring high-order network dynamics in brains and stock markets

  Kunal Jha, Daniel Carstensen, Ansh Patel, and Jeremy R. Manning

  Human cognition is fundamentally a network phenomenon: our thoughts, sense of self, and our other brain functions reflect coordinated interactions between our brain’s constituent cells and systems. These interactions change over time alongside our experiences, goals, and internally driven thoughts. Whereas early work on neural decoding attempted to infer internal representations by considering univariate (single region) or multivariate (patterns of regions) activity patterns, later studies have treated patterns of network interactions as a core unit of neural representation and computation. The field has also started to consider the potential role of higher order network interactions. If two regions, A and B, adjust their interactions over time in response to ongoing task demands, and two other regions, C and D, also adjust their interactions over time, second order interactions denote potential associations between the A-B interactions and C-D interactions. In the general case, order n interactions reflect associations between networks of order n - 1 interactions. In a recent study, our team found that meaningful high-order interactions between brain networks spontaneously emerge during deep cognitive processing, and they spontaneously dissociate during less demanding or focused cognition. Here we wondered if other sorts of networks might show a similar pattern. We applied a model of high-order network dynamics to a financial dataset comprising historical stock quotes from the S&P 500. We estimated which orders of interactions were most reflective of the “true” system dynamics by using different sets of features (made of network patterns at different orders) to predict future states of the market. We compared how informative different orders of interactions in financial data were at predicting future states of the S&P 500 to how informative different orders of brain interactions were in different experimental conditions in a neuroscientific dataset. We found that, like biological brains, financial markets appear to contain meaningful high-order interactions that change over time with market conditions, important historical events, and so on.

• 

  Cryogel Scaffold Mediated Bone Regeneration for Improved Metastatic Bone Disease Treatments

  Annika Nikhar, Peter Bertone, Eric Henderson, and Katherine Hixon

  Nearly 50% of cancers originating in organs such as the breast, prostate, and lungs spread to the skeleton. Typical metastatic bone disease (MBD) treatments include radiation and surgery; however, these interventions often bear adverse effects including infection, soft-tissue damage, and osteoporosis. Thus, improved bone regeneration could revolutionize MBD treatments where cryogel scaffolds offer a viable option. This project investigates cryogel incorporation with current radiotherapy (RT) treatments following bone tumor resection. Alternatively, FLASH RT irradiates tissue within ultra-short durations at high doses, reducing tissue toxicity and treatment time. However, the effects of FLASH on the material properties remains unclear. Cryogels were hydrated in phosphate-buffered saline (PBS), mimicking in vivo conditions, and exposed to conventional or FLASH RT at varying clinically-relevant fractionated doses. All samples were then assessed for translation potential (i.e., porosity, mechanical integrity, and swelling kinetics). To determine whether hydrated cryogels exhibited property changes due to effects of irradiation or potential degradation from PBS, non-irradiated control cryogels were immersed in PBS for parallel fractionated doses. We hypothesized that hydrating cryogels in PBS during RT exposures will not affect material physical properties.