Talk:Stratum corneum

Whoa
This is a little excessive, in my opnion. Uncited statements are the bane of Wikipedia, I agree. However, there's usually no need to remove genuinely good content from articles, even when they are uncited. The goal should be to find sources and add references where appropriate, not delete content en bloc. I've reverted most of these edits and will try to find references where possible. Cheers, David Iberri (talk) 00:44, 18 October 2008 (UTC)
 * Thank you for your input, and offering to add the references. Also, do you have an interest in dermatology (or do any of your friends?)?  Perhaps you would consider joining the WikiProject Medicine/Dermatology task force - Kilbad (talk) 00:47, 18 October 2008 (UTC)
 * When are citations going to be added to this article? kilbad (talk) 00:12, 18 November 2008 (UTC)

Water wrinkles
As explained in wrinkle there's a new and differing explanation for water wrinkles. (electrolytes) This should be added here. Then the previous statement should be re-phrased. 71.236.26.74 (talk) 19:33, 4 June 2009 (UTC)

Oil layer??
In publications for laypeople they often explain that the skin is protected by an "oily layer". Would that be on top of the Stratum corneum or is the stratum corneum what they are referring to. Maybe a paragraph or phrase should be added here somewhere. 71.236.26.74 (talk) 19:45, 4 June 2009 (UTC)


 * Hey there - I've never heard of an 'oily layer' before, but it's likely they are referring to the stratum corneum since no other 'layers' exist above this and the SC consists of intercellular lipids KingMunch (talk) 04:57, 19 June 2011 (UTC)

this could refer to the secretions from different sweat glands on the skin, many of which are sebaceous or oily and help make the skin waterproof. Sebum is the main component. Additionally secretions often have antimicrobial peptides like defensin that are part of the immune system. this is on the page "skin secretions (human)" Corduroy pillows making headlines (talk) 23:00, 13 May 2018 (UTC)

This could refer to two things: either the acid mantle, which is a layer of sweat and sebum that sits on top of the stratum corneum, or the 'lipid barrier', a matrix of lipids that permeates the stratum corneum. --Julia Ruby (talk) 08:12, 7 January 2021 (UTC)

Acid mantle link
I'd add that in a "Also see" section. After googling the term I'm rather suspicious that this is not the proper scientific term and that that article should actually be a redirect to somewhere else. Could s.o. check and add either the redirect or the link here? 71.236.26.74 (talk) 19:45, 4 June 2009 (UTC)

Suggestions for tidies
I appreciated most of what this article currently conveys, but would get even more from it if a couple of puzzles could be reconciled.

1. "the thin air-filled stratum disjunctum". That seems in conflict with it being occupied by sloughing cells. So it can't be an actual pocket of air. I'm pretty sure it's simply the region where skin cells meet the air, no?

2. "stratum corneum contains 15 to 20 layers of dead cells". Yet in both the sketch figure and the microscope image, the stratum corneum seems more like 10 cells deep.

3. It would be extremely helpful to see the layers in the microscope image labeled, as it's hard to see how they correspond to the labeled sketch. It might be the case that the particular stains used don't highlight all the layers perhaps?

Gwideman (talk) 22:17, 12 January 2010 (UTC)

Proposed merger of acid mantle with stratum corneum
The acid mantle is merely the uppermost region of the SC. The information on that page could be included in the current SC page. See: http://www.ncbi.nlm.nih.gov/pubmed/11442748 KingMunch (talk) 05:12, 19 June 2011 (UTC)
 * The acidity (pH+) of the SC is controlled by the complex flow of sweat (acidic fluids & oils) from the sweat ducts, the metabolites / transformation metabolism down thru the aging/ rising cells, & the water and new cells migrating up from below. The complementary acid & water gradients makes the entire SC gradually more acid as you move outward, ensuring that the microbial flora are relatively stable in their stratified environmental layers (somewhat like the eco/niche-layers in a forest).  According to some old well known, & recent Human Biome related studies, this layering requires an invading organism to penetrate a variety of complex ecologies before it can breach the skin. --Wikidity (talk) 00:25, 10 October 2013 (UTC)

Stratum Lucidum (SL) phase in callus formation
"stratum corneum contains 15 to 20 layers of dead cells" : 'Layers' might be a little misleading, in that it is better described as a distinct layer about 10 to 50 cells thick, that gradually change over a few weeks, as they age and rise, from plump to squamous. The stem cells in the germination layer (phase) give rise to daughter cells in a spiny phase which normally divide randomly until they enter the stratum granulosum or grainy phase of dessication & keratin building as they flatten and interlace like a heap of thin pancakes. If the skin is regularly or consistently subject to enough structural stress throughout its thickness (and the life of these cells), the grainy cells morph enough to form the stratum lucidum (SL or clear phase without distinct organelles) which makes them structurally stable (tough) enough to maintain cohesion significantly longer (than un-stressed skin), producing a much thicker and keratin rich outer callus layer. The much denser cells after the SL phase are more prone (if soaked in fresh water) to water absorption and expansion of up to 4 times their normal volume, giving the 'Prune fingers' effect before they rupture. --Wikidity (talk) 22:23, 10 October 2013 (UTC)

'These cells can also absorb water'
With regard to this section...

Cells of the stratum corneum contain a dense network of keratin, a protein that helps keep the skin hydrated by preventing water evaporation. These cells can also absorb water, further aiding in hydration. ...i'd like to know from where 'These cells can also absorb water' the water is coming. Is it locally from the organism or from water vapor present in the air or both. Is it generally accepted fact, or can it be cited? Evaporation prevention is mentioned, is this achieved by binding internal water and/or harvesting water vapor with, for example salts? — Preceding unsigned comment added by 79.66.104.238 (talk) 14:54, 3 June 2016 (UTC)

My understanding is that this water mostly comes from the blood, permeating up from the deeper vascularised layers of the skin. Water that comes into contact with the skin can also be absorbed, for example while bathing, swimming, or getting caught in the rain. My understanding is that claims as to the skin absorbing a meaningful amount of water from the air are dubious at best. --Julia Ruby (talk) 08:15, 7 January 2021 (UTC)

Ceramide:Cholesterol:Fatty Acid ratio
I have removed a vague statement regarding the impact of this ratio on the properties of the lipid component of the SC, as it lacks clarity and nuance. The cited paper discusses an incomplete model of this lipid mixture. It does not include, nor examine, the impact of the full range of ceramides and fatty acids present in the skin. Sources examining the influence of the ratios of different fatty acids and the ratios of different ceramides are needed to support any statements about the impact of the overall Cera:Chol:FA ratio. --Julia Ruby (talk) 08:18, 7 January 2021 (UTC)