Project description:The widely used white light-emitting diodes (LED) deliver higher levels of blue light than do conventional domestic light sources. The high intensity of blue component is the main source of concern about the health risks of LED with respect to their light-toxicity to the retina. White LED light with higher correlated color temperature (CCT) is more likely to cause retinal injury in mice, significantly reducing the number of ONL nuclei, however apoptosis pathway may not be the only mechanism. We used the Affymetrix GeneChip (Mouse Genome 430 2.0) to describe the different influence on gene expression of mouse retina under white LED light with different CCT.
Project description:Electric light has enabled humans to conquer the night, but light exposure at night can disrupt the circadian timing system and is associated with a diverse range of health disorders. To provide adequate lighting for visual tasks without disrupting the human circadian timing system, a precise definition of circadian spectral sensitivity is required. Prior attempts to define the circadian spectral sensitivity curve have used short (≤90-min) monochromatic light exposures in dark-adapted human subjects or in vitro dark-adapted isolated retina or melanopsin. Several lines of evidence suggest that these dark-adapted circadian spectral sensitivity curves, in addition to 430- to 499-nm (blue) wavelength sensitivity, may include transient 400- to 429-nm (violet) and 500- to 560-nm (green) components mediated by cone- and rod-originated extrinsic inputs to intrinsically photosensitive retinal ganglion cells (ipRGCs), which decay over the first 2 h of extended light exposure. To test the hypothesis that the human circadian spectral sensitivity in light-adapted conditions may have a narrower, predominantly blue, sensitivity, we used 12-h continuous exposures of light-adapted healthy human subjects to 6 polychromatic white light-emitting diode (LED) light sources with diverse spectral power distributions at recommended workplace levels of illumination (540 lux) to determine their effect on the area under curve of the overnight (2000-0800 h) salivary melatonin. We derived a narrow steady-state human Circadian Potency spectral sensitivity curve with a peak at 477 nm and a full-width half-maximum of 438 to 493 nm. This light-adapted Circadian Potency spectral sensitivity permits the development of spectrally engineered LED light sources to minimize circadian disruption and address the health risks of light exposure at night in our 24/7 society, by alternating between daytime circadian stimulatory white light spectra and nocturnal circadian protective white light spectra.
Project description:To investigate light-regulated miRNAs in the human retina we photostimulated retinal organoids and found 51 light-regulated miRNAs that are significantly up- or down-regulated.
Project description:It is a randomized controlled trial with tandem colonoscopy.Participants were randomized for use of either blue laser imaging or conventional White Light Colonoscopy on withdrawal method.comparison of detection and miss rates of BLI group Versus conventional White Light Colonoscopy.
Project description:Microarray analysis of murine retinal light damage reveals changes in iron regulatory, complement, and antioxidant genes in the neurosensory retina and isolated retinal pigment epithelium (RPE). With the advent of microarrays representing most of the transcriptome and techniques to obtain RNA from the isolated RPE monolayer, we have probed the response of the RPE and neurosensory retina (NSR) to light damage. Mice were exposed to 10,000 lux cool white fluorescent light for 18 hours and sacrificed 4 hours after photic injury. NSR and isolated RPE were collected, and RNA was isolated. DNA microarray hybridization was conducted as described in the Affymetrix GeneChip Expression Analysis Technical Manual. Microarray analysis was performed using probe intensity data derived from the Mouse Gene 1.0 ST Array. For the genes of interest, confirmation of gene expression was done using quantitative real-time PCR. Immunofluorescence assessed protein levels and localization.
Project description:The purpose of the study is to assess whether the use of I-scan during colonoscopy leads to an increased yield of adenomas in the colon among a population at increased risk for CRC.
Primary Outcome:
To estimate the mean number of adenomas per colonoscopy for both high definition white light colonoscopy and I-scan enhanced colonoscopy
Secondary Outcomes:
1. To estimate the recruitment rate
2. Number of adenomas detected in the right colon during the second look
Project description:Transcriptional profiling of wild-type and kdmA deletion mutant in response to white light exposure, against a wild-type dark-incubated reference
Project description:Interventions: narrow-band imagaing
white light
Primary outcome(s): Comparison of narrow-band imaging versus white light imaging for diminutive adenoma detection rate
Study Design: Parallel Randomized