Micro and nanoscale patterning of surface features and biochemical cues have emerged as tools to precisely direct neurite growth into close proximity with next generation neural prosthesis electrodes. Biophysical cues can exert greater influence on neurite pathfinding compared to the more well studied biochemical cues; yet the signaling events underlying the ability of growth cones to respond to these microfeatures remain obscure. Intracellular Ca2+ signaling plays a critical role in how a growth cone senses and grows in response to various cues (biophysical features, repulsive peptides, chemo-attractive gradients).
View Article and Find Full Text PDF. Cochlear implants provide auditory perception to those with severe to profound sensorineural hearing loss: however, the quality of sound perceived by users does not approximate natural hearing. This limitation is due in part to the large physical gap between the stimulating electrodes and their target neurons.
View Article and Find Full Text PDFCochlear implants (CIs) provide auditory perception to those with profound sensorineural hearing loss: however, the quality of sound perceived by a CI user does not approximate natural hearing. This limitation is due in part to the large physical gap between the stimulating electrodes and their target neurons. Therefore, directing the controlled outgrowth of processes from spiral ganglion neurons (SGNs) into close proximity to the electrode array could provide significantly increased hearing function.
View Article and Find Full Text PDFQuantitative analysis of neurite growth and morphology is essential for understanding the determinants of neural development and regeneration, however, it is complicated by the labor-intensive process of measuring diverse parameters of neurite outgrowth. Consequently, automated approaches have been developed to study neurite morphology in a high-throughput and comprehensive manner. These approaches include computer-automated algorithms known as 'convolutional neural networks' (CNNs)-powerful models capable of learning complex tasks without the biases of hand-crafted models.
View Article and Find Full Text PDFCaldendrin is a Ca binding protein that interacts with multiple effectors, such as the Ca1 L-type Ca channel, which play a prominent role in regulating the outgrowth of dendrites and axons (i.e., neurites) during development and in response to injury.
View Article and Find Full Text PDFBackground: During development or regeneration, neurons extend processes (i.e., neurites) via mechanisms that can be readily analyzed in culture.
View Article and Find Full Text PDFFunctional outcomes with neural prosthetic devices, such as cochlear implants, are limited in part due to physical separation between the stimulating elements and the neurons they stimulate. One strategy to close this gap aims to precisely guide neurite regeneration to position the neurites in closer proximity to electrode arrays. Here, we explore the ability of micropatterned biochemical and topographic guidance cues, singly and in combination, to direct the growth of spiral ganglion neuron (SGN) neurites, the neurons targeted by cochlear implants.
View Article and Find Full Text PDFCalcium (Ca2+) plays a central role in regulating many biological processes in the cell from muscle contraction to neurotransmitter release. The need for reliable fluorescent calcium indicator dyes is of vast importance for studying many aspects of cell biology as well as screening compounds using phenotypic high throughput assays. We have assessed two of the latest generation of calcium indicator dyes, FLIPR Calcium 6 and Cal-520 AM for studying calcium transients (CaTs) in induced pluripotent stem cell (iPSC) -derived human cardiomyocytes.
View Article and Find Full Text PDFMesenchymal stromal/stem cells (MSCs) have demonstrated favorable wound healing properties in addition to their differentiation capacity. MSCs encapsulated in biomaterials such as gelatin and polyethylene glycol (PEG) composite hydrogels have displayed an immunophenotype change that leads to the release of cytokines and growth factors to accelerate wound healing. However, therapeutic potential of implanted MSC-loaded hydrogels may be limited by non-specific protein adsorption that facilitates adhesion of bacterial pathogens such as planktonic Staphylococcus aureus (SA) to the surface with subsequent biofilm formation resistant to immune cell recognition and antibiotic activity.
View Article and Find Full Text PDFArch Stem Cell Res
November 2016
Pluripotent Stem Cells were originally derived and cultured using a feeder layer of cells. Movements have been undertaken to transition from this method to one more defined, high-throughput, and without xenogenic factors. Tremendous research has been done in this area and many products have been developed, however, based on our analysis of recent publications in stem cell related journals many in academia are still using older methods like a feeder layer.
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