Multimodal epidermal devices for hydration monitoring.
Ontology highlight
ABSTRACT:
SUBMITTER: Krishnan S
PROVIDER: S-EPMC6444991 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:We hypothesized that treatment of the injured skin with occlusion limits TEWL and results in a phenotype of epithelial response that more closely resembles mucosa. Here we addressed whether different hydration conditions change gene expression patterns in epidermis using microarray study in rabbit partial-thickness incisional wound. Microarray on epidermis showed that global expression patterns of the genes in full occluded vs. non-occluded wounds are distinct. Many genes - including IL-1M-NM-2, IL-8, TNF-M-NM-1, and COX-2-upregulated in skin environment were also upregulated in non-occluded wounds. Simulating increased TEWL showed increased expression of proinflammatory genes in human ex vivo skin culture (HESC) and stratified keratinocytes. Microarray on epidermis showed that global expression patterns of the genes in full occluded vs. non-occluded wounds are distinct. Female New Zealand White rabbits (3-4 kg) were purchased from Covance (Princeton, NJ) and were acclimated for a minimum of 7 days prior to experiments. Ketamine (45 mg/kg) and xylazine (7 mg/kg) were injected intramuscularly as primary anesthesia method prior to the procedure. The procedure was performed while the animal was in full anesthesia with the vital sign checking every 15 min including heart beat, breath frequency, and body temperature. Buprenex (0.05 mg/kg) was applied by intradermal injection prior to the surgery and continued every 6-12 hours for 24 hours after surgery. The animals were all monitored closely for signs of discomfort post surgeries. Tissue harvests were performed following euthanasia. The superficial incisional grids on rabbit ear were created by using a double blade scalpel with 1 mm space between the two blades. A single layer of Tegaderm was used to cover the wounding areas on both right and left ears until the wounding areas were fully re-epithelialized (two days post wounding, POE0). Thereafter, the Tegaderm on right ear was completely removed (NOW) while four more layers of Tegaderms were applied on left ear wounds (FOW). Rabbit ear samples were harvested at POE0, POE3 and POE5.
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