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In this Letter, we report a low-cost, portable, two-photon excitation fluorescence microscopy imager that uses a fiber-based approach for both femtosecond supercontinuum (SC) generation and light delivery to the optical head. The SC generation is based on a tapered polarization-maintaining photonic crystal fiber that uses pre-chirped femtosecond narrowband pulses to generate a coherent SC spectrum with a bandwidth of approximately 300 nm. Using this approach, high-power, near-transform-limited, wavelength-selectable SC pulses are generated and directly delivered to the imaging optical head. Preliminary testing of this imager on brain slices is presented, demonstrating a high signal-to-noise ratio and sub-cellular imaging capabilities to a depth of approximately 200 µm. These results demonstrate the suitability of the technology forex vivoand potentiallyin vivocellular-level biomedical imaging applications.
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The polyglutamine protein FAM171B localizes to neuronal cytoplasm
Expansion mutation within polyglutamine (polyQ) tract proteins is known to underlie a number of severe neurodegenerative disorders such as Huntington’s Disease and Spinocerebellar Ataxia. Using a bioinformatics approach, we have identied a novel protein, FAM171B, that contains a stretch of 14 consecutive glutamines. Using in situ hybridization and immunohistochemistry experiments, our data strongly suggests that FAM171B is widely expressed in the brain with abundant expression in the hippocampus, cortex, and cerebellum. To begin elucidating FAM171B sub-cellular location we are using confocal uorescence imaging of GFP-fusion tagged FAM171B and anti-FAM171B antibodies in vitro. Our ndings indicate that FAM171B displays a punctate/vesicular staining pattern throughout the cytoplasm of human glioblastoma tissue culture cells and primary mouse cortical neurons. FAM171B localization is particularly enriched in the peri-nuclear region and adjacent to the plasma membrane. Current studies are utilizing organelle specic markers to verify sub-cellular locale and live-cell imaging to assay whether FAM171B may trac between intracellular compartments.
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- Award ID(s):
- 1726859
- PAR ID:
- 10112191
- Date Published:
- Journal Name:
- Abstracts - Society for Neuroscience
- ISSN:
- 0190-5295
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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- The DOI is not currently available.
