Hair and Nails
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Research
Nails and hair are the accessory structure of the skin which makes an integumentary system. The function of both is largely dependent on their anatomical structure ADDIN ZOTERO_ITEM CSL_CITATION {"citationID":"S8tjZTWd","properties":{"formattedCitation":"(Dr, 2014)","plainCitation":"(Dr, 2014)","noteIndex":0},"citationItems":[{"id":154,"uris":["http://zotero.org/users/local/CKNkWnK9/items/49BQV3GQ"],"uri":["http://zotero.org/users/local/CKNkWnK9/items/49BQV3GQ"],"itemData":{"id":154,"type":"book","title":"Anatomy & Physiology: The Unity of Form and Function","publisher":"McGraw-Hill Education","number-of-pages":"1248","source":"Google Books","abstract":"A Doody's Core Title for 2017!With Saladin, students make connections through learning outcomes and assessments, integrated media, and a writing style that clearly depicts anatomy and physiology processes. A consistent set of chapter learning tools helps students identify and retain key concepts while the stunning visual program provides a realistic view of body structures and processes.Saladin's text requires no prior knowledge of college chemistry or cell biology, and is designed for a two-semester A&P course. Users who purchase Connect Plus receive access to the full online ebook version of the textbook, as well full access to LearnSmart, SmartBook, and Anatomy & Physiology Revealed. The seventh edition's changes focus primarily on new science (30+ updates based on advances in science), new writing (30+ new sections of text to improve discussion, update terminology, and include new Deeper Insight examples), and 40+ new and revised photos and illustrations. Also, a new appendix has been added to the 7th edition to include the complete genetic code. Significant improvements have also been made to the Connect question banks.","ISBN":"978-0-07-340371-7","note":"Google-Books-ID: lmr8nQEACAAJ","title-short":"Anatomy & Physiology","language":"en","author":[{"family":"Dr","given":"Kenneth S. Saladin"}],"issued":{"date-parts":[["2014",1,7]]}}}],"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"} (Dr, 2014). Both are made up of dead keratinized proteins that protect skin and finger extremities. This anatomical relationship shows that both of them originate from the ectoderm, which is the outer most layer of skin. Inside a hair follicle bulge from which a hair originates, the epidermis is connected to erector pili muscles which are responsible for skin insulation ADDIN ZOTERO_ITEM CSL_CITATION {"citationID":"LXIbKEG8","properties":{"formattedCitation":"(Fujiwara et al., 2011)","plainCitation":"(Fujiwara et al., 2011)","noteIndex":0},"citationItems":[{"id":167,"uris":["http://zotero.org/users/local/CKNkWnK9/items/2MR53K2M"],"uri":["http://zotero.org/users/local/CKNkWnK9/items/2MR53K2M"],"itemData":{"id":167,"type":"article-journal","title":"The Basement Membrane of Hair Follicle Stem Cells Is a Muscle Cell Niche","container-title":"Cell","page":"577-589","volume":"144","issue":"4","source":"www.cell.com","abstract":"<h2>Summary</h2><p>The hair follicle bulge in the epidermis associates with the arrector pili muscle (APM) that is responsible for piloerection (\"goosebumps\"). We show that stem cells in the bulge deposit nephronectin into the underlying basement membrane, thus regulating the adhesion of mesenchymal cells expressing the nephronectin receptor, α8β1 integrin, to the bulge. Nephronectin induces α8 integrin-positive mesenchymal cells to upregulate smooth muscle markers. In nephronectin knockout mice, fewer arrector pili muscles form in the skin, and they attach to the follicle above the bulge, where there is compensatory upregulation of the nephronectin family member EGFL6. Deletion of α8 integrin also abolishes selective APM anchorage to the bulge. Nephronectin is a Wnt target; epidermal β-catenin activation upregulates epidermal nephronectin and dermal α8 integrin expression. Thus, bulge stem cells, via nephronectin expression, create a smooth muscle cell niche and act as tendon cells for the APM. Our results reveal a functional role for basement membrane heterogeneity in tissue patterning.</p><h3>PaperClip</h3>","DOI":"10.1016/j.cell.2011.01.014","ISSN":"0092-8674, 1097-4172","note":"PMID: 21335239","journalAbbreviation":"Cell","language":"English","author":[{"family":"Fujiwara","given":"Hironobu"},{"family":"Ferreira","given":"Manuela"},{"family":"Donati","given":"Giacomo"},{"family":"Marciano","given":"Denise K."},{"family":"Linton","given":"James M."},{"family":"Sato","given":"Yuya"},{"family":"Hartner","given":"Andrea"},{"family":"Sekiguchi","given":"Kiyotoshi"},{"family":"Reichardt","given":"Louis F."},{"family":"Watt","given":"Fiona M."}],"issued":{"date-parts":[["2011",2,18]]}}}],"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"} (Fujiwara et al., 2011).
Critical thinking
The skin has three different layers known as 1) the outermost “epidermis” 2) the middle “dermis” and 3) the innermost “Endodermis” ADDIN ZOTERO_ITEM CSL_CITATION {"citationID":"YOWGnJMC","properties":{"formattedCitation":"(Dr, 2014)","plainCitation":"(Dr, 2014)","noteIndex":0},"citationItems":[{"id":154,"uris":["http://zotero.org/users/local/CKNkWnK9/items/49BQV3GQ"],"uri":["http://zotero.org/users/local/CKNkWnK9/items/49BQV3GQ"],"itemData":{"id":154,"type":"book","title":"Anatomy & Physiology: The Unity of Form and Function","publisher":"McGraw-Hill Education","number-of-pages":"1248","source":"Google Books","abstract":"A Doody's Core Title for 2017!With Saladin, students make connections through learning outcomes and assessments, integrated media, and a writing style that clearly depicts anatomy and physiology processes. A consistent set of chapter learning tools helps students identify and retain key concepts while the stunning visual program provides a realistic view of body structures and processes.Saladin's text requires no prior knowledge of college chemistry or cell biology, and is designed for a two-semester A&P course. Users who purchase Connect Plus receive access to the full online ebook version of the textbook, as well full access to LearnSmart, SmartBook, and Anatomy & Physiology Revealed. The seventh edition's changes focus primarily on new science (30+ updates based on advances in science), new writing (30+ new sections of text to improve discussion, update terminology, and include new Deeper Insight examples), and 40+ new and revised photos and illustrations. Also, a new appendix has been added to the 7th edition to include the complete genetic code. Significant improvements have also been made to the Connect question banks.","ISBN":"978-0-07-340371-7","note":"Google-Books-ID: lmr8nQEACAAJ","title-short":"Anatomy & Physiology","language":"en","author":[{"family":"Dr","given":"Kenneth S. Saladin"}],"issued":{"date-parts":[["2014",1,7]]}}}],"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"} (Dr, 2014). Both hair and nail are originated from the outermost layer epidermis. The function is highly dependent on the physiological structure of hair and nails which can be proved by the mechanism of “Pilo Erection”. Pilo erection is a process in which the hair on the surface of the human body erect in response to emotion and cold ADDIN ZOTERO_ITEM CSL_CITATION {"citationID":"2kmtD9ee","properties":{"formattedCitation":"(Torkamani, Rufaut, Jones, & Sinclair, 2014)","plainCitation":"(Torkamani, Rufaut, Jones, & Sinclair, 2014)","noteIndex":0},"citationItems":[{"id":171,"uris":["http://zotero.org/users/local/CKNkWnK9/items/QWR3KJ44"],"uri":["http://zotero.org/users/local/CKNkWnK9/items/QWR3KJ44"],"itemData":{"id":171,"type":"article-journal","title":"Beyond Goosebumps: Does the Arrector Pili Muscle Have a Role in Hair Loss?","container-title":"International Journal of Trichology","page":"88-94","volume":"6","issue":"3","source":"PubMed Central","abstract":"The arrector pili muscle (APM) consists of a small band of smooth muscle that connects the hair follicle to the connective tissue of the basement membrane. The APM mediates thermoregulation by contracting to increase air-trapping, but was thought to be vestigial in humans. The APM attaches proximally to the hair follicle at the bulge, a known stem cell niche. Recent studies have been directed toward this muscle's possible role in maintaining the follicular integrity and stability. This review summarizes APM anatomy and physiology and then discusses the relationship between the follicular unit and the APM. The potential role of the APM in hair loss disorders is also described, and a model explaining APM changes in hair loss is proposed.","DOI":"10.4103/0974-7753.139077","ISSN":"0974-7753","note":"PMID: 25210331\nPMCID: PMC4158628","title-short":"Beyond Goosebumps","journalAbbreviation":"Int J Trichology","author":[{"family":"Torkamani","given":"Niloufar"},{"family":"Rufaut","given":"Nicholas W"},{"family":"Jones","given":"Leslie"},{"family":"Sinclair","given":"Rodney D"}],"issued":{"date-parts":[["2014"]]}}}],"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"} (Torkamani, Rufaut, Jones, & Sinclair, 2014). Did you ever go out in the middle of a chilly night and experienced “Goosebumps”? This a body’s normal response to maintaining homeostasis. These goosebumps serve as a function of protection. They trap the necessary air inside, creating a layer of insulation that brings the body back to the normal temperature. Now the question is how the structure of hair plays a role in this process?
The epidermis layer constitutes a root of a hair which is called a hair follicle. In the base of the hair follicle, the epidermis is connected to the smooth muscles called “Erector Pilli muscles”. It usually extends to the second layer of skin called the dermis. When Erector Pilli muscles contract as a result of the response from the sympathetic nerve system, they lead to the erection of the hairs ADDIN ZOTERO_ITEM CSL_CITATION {"citationID":"zp0AAlTi","properties":{"formattedCitation":"(Fujiwara et al., 2011)","plainCitation":"(Fujiwara et al., 2011)","noteIndex":0},"citationItems":[{"id":167,"uris":["http://zotero.org/users/local/CKNkWnK9/items/2MR53K2M"],"uri":["http://zotero.org/users/local/CKNkWnK9/items/2MR53K2M"],"itemData":{"id":167,"type":"article-journal","title":"The Basement Membrane of Hair Follicle Stem Cells Is a Muscle Cell Niche","container-title":"Cell","page":"577-589","volume":"144","issue":"4","source":"www.cell.com","abstract":"<h2>Summary</h2><p>The hair follicle bulge in the epidermis associates with the arrector pili muscle (APM) that is responsible for piloerection (\"goosebumps\"). We show that stem cells in the bulge deposit nephronectin into the underlying basement membrane, thus regulating the adhesion of mesenchymal cells expressing the nephronectin receptor, α8β1 integrin, to the bulge. Nephronectin induces α8 integrin-positive mesenchymal cells to upregulate smooth muscle markers. In nephronectin knockout mice, fewer arrector pili muscles form in the skin, and they attach to the follicle above the bulge, where there is compensatory upregulation of the nephronectin family member EGFL6. Deletion of α8 integrin also abolishes selective APM anchorage to the bulge. Nephronectin is a Wnt target; epidermal β-catenin activation upregulates epidermal nephronectin and dermal α8 integrin expression. Thus, bulge stem cells, via nephronectin expression, create a smooth muscle cell niche and act as tendon cells for the APM. Our results reveal a functional role for basement membrane heterogeneity in tissue patterning.</p><h3>PaperClip</h3>","DOI":"10.1016/j.cell.2011.01.014","ISSN":"0092-8674, 1097-4172","note":"PMID: 21335239","journalAbbreviation":"Cell","language":"English","author":[{"family":"Fujiwara","given":"Hironobu"},{"family":"Ferreira","given":"Manuela"},{"family":"Donati","given":"Giacomo"},{"family":"Marciano","given":"Denise K."},{"family":"Linton","given":"James M."},{"family":"Sato","given":"Yuya"},{"family":"Hartner","given":"Andrea"},{"family":"Sekiguchi","given":"Kiyotoshi"},{"family":"Reichardt","given":"Louis F."},{"family":"Watt","given":"Fiona M."}],"issued":{"date-parts":[["2011",2,18]]}}}],"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"} (Fujiwara et al., 2011). This phenomenon is normally observed in humans. However, organism with heavy hair coats are more likely to exhibit this behavior.
References
ADDIN ZOTERO_BIBL {"uncited":[],"omitted":[],"custom":[]} CSL_BIBLIOGRAPHY Dr, K. S. S. (2014). Anatomy & Physiology: The Unity of Form and Function. McGraw-Hill Education.
Fujiwara, H., Ferreira, M., Donati, G., Marciano, D. K., Linton, J. M., Sato, Y., … Watt, F. M. (2011). The Basement Membrane of Hair Follicle Stem Cells Is a Muscle Cell Niche. Cell, 144(4), 577–589. https://doi.org/10.1016/j.cell.2011.01.014
Torkamani, N., Rufaut, N. W., Jones, L., & Sinclair, R. D. (2014). Beyond Goosebumps: Does the Arrector Pili Muscle Have a Role in Hair Loss? International Journal of Trichology, 6(3), 88–94. https://doi.org/10.4103/0974-7753.139077
