[Illinois] Beckman Graduate Seminar: Graphene Atomic Shrink Wrap for Nanosandwiching Biomolecules
20 Jun 2013 | Online Presentations | Contributor(s): Joshua D. Wood
Graphene, a two-dimensional honeycomb sheet of carbon atoms, has been hotly scrutinized for its desirable electronic applications. Still, graphene has hardly been used as an atomically thin membrane. Graphene membranes are conformal to surfaces, entrapping liquids, gases, and nanoparticles. Here, we use centimeter sheets of grown graphene membranes on Cu to make graphene-biomolecule nanosandwiches. To that end, we cleanly layer graphene using a novel polymer support, poly(bisphenol A carbonate). We nanosandwich PC-transferred graphene sheets with tobacco mosaic viruses (TMV), NeutrAvidin (NA) proteins, and a complex of MBD1 protein attached to methylated DNA (MBD-DNA). …
[Illinois] Beckman Graduate Seminar: Frontoparietal traffic signals: A fast optical imaging study of preparatory dynamics in response mode switching
20 Jun 2013 | Online Presentations | Contributor(s): Pauline L. Baniqued
Coordination between networks of brain regions is important for optimal cognitive performance, especially in attention demanding tasks. With the event-related optical signal (EROS; a measure of changes in optical scattering due to neuronal activity) we can characterize rapidly evolving network processes by examining the millisecond-scale temporal …
[Illinois] Beckman Graduate Seminar: Neural Correlates of Externally and Internally Originating Emotional Distraction Effects on Working Memory
20 Jun 2013 | Online Presentations | Contributor(s): Alexandru D. Iordan
Balanced emotion-cognition interactions are critical for healthy functioning. Clinical studies suggest that symptoms of impaired executive control and enhanced emotional distractibility observed in affective disorders are linked to dysfunctional interactions between a dorsal executive system and a ventral emotional system. Recent studies investigating the neural correlates of working memory interference by emotional distraction have provided evidence that interactions between these two systems can also occur transiently, in response to on-going task irrelevant emotional distracters. …
[Illinois] BioNanotechnology Seminar Series Spring 2012: Cationic, Helical Polypeptide Based Gene Delivery for IMR90 Fibroblasts and Human Embryonic Stem Cells
13 Jun 2013 | Online Presentations | Contributor(s): Jonathan Yen
New diblock copolymers consisting of poly(ethyleneglycol)-block-poly(?-(4-(piperidin-1-yl)ethanaminomethylbenzyl)-L-glutamate), PEG-b-PVBLG-8 were synthesized for the effective transfection of hard to transfect cells like IMR90, human fetal lung fibroblasts and human embryonic stem cells (hESC). The diblock copolymers maintain a water soluble cationic helical polypeptides block, with the PEG reducing toxicity of the PVBLG-8. It also allows the copolymer to maintain its high helical content, without dramatically compromising its ability to condense the DNA. Polymers with varying degrees of polymerization of PVBLG-8 were synthesized to identify the most effective vehicle for gene delivery.
The diblock polymer with a polymerization degree of 287 demonstrates greater transfection efficiency and lower toxicity in IMR90 cells when compared with the commercial Lipofectamine 2000, giving a transfection efficiency of 21.4% and about 80% cell viability. We also demonstrate the potential for the polymer to be used in hESC. In summary, this polymer demonstrates the effective use of peptide based delivery vehicles for gene delivery
[Illinois] BioNanotechnology Seminar Series Spring 2012: Fabrication and Characterization of Multi-Compartment Collagen-Glycosaminoglycan Scaffolds for Tissue Regeneration
13 Jun 2013 | Online Presentations | Contributor(s): Daniel Weisgerber
We are working to create multi-compartment scaffolds as regenerative templates for multi-tissue interfaces such as the tendon to bone junction (TBJ). Collagen-glycosaminoglycan (CG) scaffolds have previously been successfully employed in a variety of soft tissue regeneration applications. Recently strategies for creating mineralized CG (CGCaP) scaffold variants along with fabrication methods to create layered osteochondral scaffolds have been demonstrated. Here I will discuss methods for the fabrication and characterization of both single and multi-compartment scaffolds targeted for the TBJ. Following production, both histology and microCT imaging approaches were employed to investigate scaffold microstructural features. In the case of the mineralized CGCaP scaffolds, mineral content as well as phase were determined via DMMB and hydroxyproline assays as well as x-ray diffraction approaches, respectively. Bulk mechanical and permeability characterization methods were applied and then compared with ultrasound elastography approaches targeting non-destructive analysis of individual scaffold compartments within the heterogeneous multi-compartment scaffolds. Finally, the biocompatibility of hMSCs within CG and CGCaP scaffold compartments was investigated using bioactivity, gene expression, and functional metrics as a precursor to both in vivo testing as well as subsequent work creating fully interpenetrating TBJ grafts that can drive multi-lineage MSC differentiation in a spatially-selective manner.