Background: Non-invasive bioengineering methods are widely used in the assessment of irritant skin reactions.
Objectives: To assess the ability of eight non-invasive measurement techniques to distinguish changes in skin conditions over time, these changes being induced by five different irritants.
Methods: The following techniques were compared in a multivariate analysis: laser-Doppler perfusion imaging (LDI), laser-Doppler flowmetry (LDF), transepidermal water loss (TEWL), visual scoring (VS), colorimetric measurements (Chromameter CR 200 a* and L* scales), Mexameter Hb scale (Mexa Hb) and capacitance (Corneometer CM 820).
The differences between pre- and postmenopausal women and men on corneocyte surface area were investigated by a noninvasive exfoliation method. Surface corneocytes were collected with a modified detergent scrub technique. Separated corneocytes were analyzed by videomicroscopy and image analyses (NIH Image 1.
View Article and Find Full Text PDFTwo studies were performed to evaluate the influence of glycerol on the recovery of damaged stratum corneum barrier function. Measurements of transepidermal water loss and capacitance were conducted in a 3-day follow-up after tape stripping (study 1) and a 7-day follow-up after a barrier damage due to a repeated washing with sodium lauryl sulphate. In study 1 a faster barrier repair (transepidermal water loss) was monitored in glycerol-treated sites.
View Article and Find Full Text PDFSkin Pharmacol Appl Skin Physiol
September 1999
Purpose Of The Study: We aimed to evaluate whether prolonged occlusion can induce stratum corneum barrier damage, alterations in stratum corneum hydration or water-holding capacity (WHC) lasting longer than the occlusion time.
Materials And Methods: 12 subjects were occluded on the forearm for 24, 48, 72 and 96 h. Two hours after occlusion removal, transepidermal water loss (TEWL) and skin hydration were measured and a sorption-desorption test performed.
Background: Heart Rate (HR) and Heart Rate Variability (HRV) depend on the neural control to the heart. HRV can be measured from 24-hours function. Little information is available on cardiac rhythm and on autonomic nervous control to the heart at birth.
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