DOCSLIB.ORG

LAB-Skin-And-Adnexa-2018.Pdf

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
LAB-Skin-And-Adnexa-2018.Pdf Skin Introduction It is easy enough to identify a basic tissue in isolation, but it takes further skill to incorporate the knowledge of these separate tissues and distinguish them as such in a compound tissue organ, such as the skin. These basic tissues will be found in some capacity in every tissue you encounter, and the function of this lab is to help you become more familiar in recognizing these specific tissues in organs. Skin is a great example of how the basic tissues combine to create a compound tissue and organ. It is a tissue composed of three distinct layers: epidermis, dermis and hypodermis. Each layer has specific functions, which are derived from their basic tissue components. Your job during this lab is to focus on identifying these basic tissues within these layers of skin and to think about the specific function they impart to the skin. Learning objectives and activities Using the Virtual Slidebox: A Examine the keratinized stratified squamous epithelium of the epidermis, and identify the modified epithelial exocrine glands. B Analyze the organization of collagen fibers and connective tissue cells in the dermis and hypodermis and interpret their function within the skin. C Locate muscle, peripheral nerve and modified nervous tissues in the skin. D Examine hair and hair follicles and determine that they are derived from the epidermis. E Investigate the anatomy of the growing fingernail and appreciate its relationship to skin. F Complete the self-quiz to test your understanding and master your learning. Epidermis: the epithelium of the skin The epidermis is a specialized epithelium: keratinized stratified squamous. The layering and apical specialization makes this epithelium prime for protection against outside forces (i.e. abrasion, bacteria, etc.) The specialized keratinocytes also prevent water loss. i. Stratum basale - single layer of cells on the basement membrane - mitotically active and responsible for the constant production of keratinocytes v - recall that hemidesmosomes anchor the . cells to the basal lamina of basement iv. membrane ii. Stratum spinosum iii. - thickest portion of the epidermis - cells synthesize keratin filaments - recall that cells are held together by desmosomes - shrinkage during preparation causes cells ii. to separate except where they are held together giving them their ‘spiny appearance. iii. Stratum granulosum - cells undergoing terminal keratinization - contain keratohyaline granules that i release filaggrin to bundle keratin . filaments - creates a water-proof barrier iv. Stratum lucidum - a layer of pale-staining keratinocytes - only seen in thick skin Examine Slide 1 (79) to locate the 5 layers v. Stratum corneum of the epidermis and its apical - flattened, dead keratinocytes and their specialization. bundled keratin - forms the protective apical specialization known as keratin Sweat and sebaceous glands: the exocrine glands of the skin In some areas of the skin, the epithelium invaginates to form an exocrine gland. There are three types of exocrine glands: eccrine/merocrine, apocrine and sebaceous. They vary in look, function and location. Be cautious not to confuse the sweat glands with blood vessels. The tubular appearance can trick the naïve eye. i. Eccrine glands - also known as merocrine glands - most widely distributed gland in the skin - coiled tubular ducts that stain dark - secretory portions have small lumens and pale- staining cells - produce what we commonly known as ‘sweat’ which has a thermoregulatory function Examine Slide 2a (78) & find examples of eccrine glands ii. Apocrine glands - vestigial glands found in the axillary and genital regions of the skin - coiled tubular ducts that stain basophilic - easily recognized by their secretory portions, which have large lumens with eosinophilic cells. - produce pheromones which trigger sexual responses and mating in many mammals Examine Slide 2b (78) & find examples of apocrine glands iii. Sebaceous glands - located throughout the skin - secretory portion is distinctly acinar and composed of pale, lipid rich cells - short ducts usually empty into hair follicle, but they can also secrete directly onto the skin - produce ‘sebum’, an oily mixture of lipids that maintains the keratin - excessive production of sebum can lead to blockage of the ducts and subsequent tissue inflammation resulting in acne. Examine Slide 2c (78) & find examples of sebaceous glands Dermis & Hypodermis: the connective tissue of the skin The dermis and hypodermis are connective tissue layers that provide support and stretch to the skin. i. Papillary dermis - is the superficial portion of the dermis composed of loose irregular connective tissue - is composed of Type I collagen fibers and Type III collagen fibrils - forms projections into the epidermis called dermal papillae This organization: - provides attached to the epidermis at the basement membrane (recall its components). - provides a large surface area for anchoring of the epidermis - provides cushioning support for: i. the overlying epidermis ii. capillary loops that feed the avascular epidermis and are involved in thermoregulation - provides a framework for the many leukocytes present and ready to respond to microbes that may infiltrate the skin barrier. Examine the papillary dermis in Slide 3a (76) and identify its major connective tissue components ii. Reticular dermis - is the deep portion of the dermis composed of dense irregular connective tissue - is composed of Type I collagen fibers and fiber bundles - also contains elastin fibers This organization: - allows the dermis to resist tensile forces from all directions - allows the skin to stretch and recoil Examine the reticular dermis in Slide 3b (76) and identify its major connective tissue components iii. Hypodermis - is the deepest layer of the skin - composed of loose irregular connective tissue and many adipocytes This organization: - provides a cushioning protection to underlying organs and supports vasculature - acts a nutritional reserve and insulation from the cold Examine the hypodermis in Slide 3c (76) and identify its major connective tissue components Depending on the region, skin will contain varying amounts of skeletal and smooth muscle. For example, in the lip you can see the skeletal muscle of the orbicularis oris muscle and smooth muscle surrounding the blood vessels that travel through the dermis and hypodermis. You can also see sections through the peripheral nerves that innervate the skin. Examine slides of skin to find areas of muscle and nerve to test your skills at observing these basic tissues in compound tissues. i. Skeletal muscle - has fibers defined by striations and peripheral nuclei in longitudinal section Examine Slide 4a - has fibers that are polygonal with peripheral nuclei in cross section (42) and find - has organizing layers of connective tissue that surround: examples of a. individual muscle fibers (endomysium) skeletal muscle in b. fascicles/collections of muscle fibers (perimysium) long & cross- c. the whole muscle (epimysium) section ii. Smooth muscle - is found circumscribing tubes (like blood vessels) Examine Slide 4b - does not have striations (42) and find - has spindle-shaped cells with cigar shaped nuclei in longitudinal section examples of - has circular cells with large round nuclei (that makes tissue look spotty) in smooth muscle in cross section long & cross- section iii. Peripheral nerve - is formed from the myelinated axons of motor and sensory neurons - has a distinctive wavy appearance in longitudinal section Examine Slide 4c - may be confused with smooth muscle (but doesn’t surround tubes!) (42) and find - may have a ‘washed out’ appearance due to lipid in myelin sheath examples of - contains the nuclei of Schwaan cells (and some fibroblasts) peripheral nerves in (mainly) iv. Modified nervous tissue in skin (touch receptors) longitudinal - there are two main types of touch receptor section a. Meissner’s corpuscles - touch receptors in the papillary dermis of fingertips, palms and soles Examine Slide 5a - composed of sensory axons surrounded by flat Schwaan cells and find - respond to light touch when they are temporarily deformed examples of Meissner’s corpuscle b. Pacinian corpuscles and Slide 5b to find - touch receptors found in the reticular dermis throughout the body Pacinian corpuscles - oval structures composed of concentric lamellae (layers) - respond to frrm pressure and vibration Hair follicles are tubular invaginations of the epidermis that project into the dermis. The hair itself forms within the follicles and is itself constructed of columns of keratin. Examine regions of hairy skin and locate the different regions of a hair follicle and hair when cut in longitudinal section (Slide 6) and in cross section (Slide 7) 1. Hair follicle a. Infundibulum Identify the extent of the - extends from the surface opening of the follicle to the infundibulum in Slide 6a opening of its sebaceous gland Find a cross section through this - is part of the pilosebaceous canal (the route for sebum region in Slide 7a discharge) Find a sebaceous gland in b. Sebaceous gland Slide 6b - its duct opens into the infundibulum where it secretes and Slide 7b sebum Identify the extent of the c. Isthmus isthmus in Slide 6c - extends from the infundibulum to the insertion of the arrector pili muscle Find a cross section through this region in Slide 7c d. Arrector pili muscle - a thin bundle of smooth muscle that extends from the papillary dermis of the skin to the connective tissue sheath surrounding
Load more

Recommended publications
  • Development and Maintenance of Epidermal Stem Cells in Skin Adnexa
    International Journal of Molecular Sciences Review Development and Maintenance of Epidermal Stem Cells in Skin Adnexa Jaroslav Mokry * and Rishikaysh Pisal Medical Faculty, Charles University, 500 03 Hradec Kralove, Czech Republic; [email protected] * Correspondence: [email protected] Received: 30 October 2020; Accepted: 18 December 2020; Published: 20 December 2020 Abstract: The skin surface is modified by numerous appendages. These structures arise from epithelial stem cells (SCs) through the induction of epidermal placodes as a result of local signalling interplay with mesenchymal cells based on the Wnt–(Dkk4)–Eda–Shh cascade. Slight modifications of the cascade, with the participation of antagonistic signalling, decide whether multipotent epidermal SCs develop in interfollicular epidermis, scales, hair/feather follicles, nails or skin glands. This review describes the roles of epidermal SCs in the development of skin adnexa and interfollicular epidermis, as well as their maintenance. Each skin structure arises from distinct pools of epidermal SCs that are harboured in specific but different niches that control SC behaviour. Such relationships explain differences in marker and gene expression patterns between particular SC subsets. The activity of well-compartmentalized epidermal SCs is orchestrated with that of other skin cells not only along the hair cycle but also in the course of skin regeneration following injury. This review highlights several membrane markers, cytoplasmic proteins and transcription factors associated with epidermal SCs. Keywords: stem cell; epidermal placode; skin adnexa; signalling; hair pigmentation; markers; keratins 1. Epidermal Stem Cells as Units of Development 1.1. Development of the Epidermis and Placode Formation The embryonic skin at very early stages of development is covered by a surface ectoderm that is a precursor to the epidermis and its multiple derivatives.
    [Show full text]
  • Te2, Part Iii
    TERMINOLOGIA EMBRYOLOGICA Second Edition International Embryological Terminology FIPAT The Federative International Programme for Anatomical Terminology A programme of the International Federation of Associations of Anatomists (IFAA) TE2, PART III Contents Caput V: Organogenesis Chapter 5: Organogenesis (continued) Systema respiratorium Respiratory system Systema urinarium Urinary system Systemata genitalia Genital systems Coeloma Coelom Glandulae endocrinae Endocrine glands Systema cardiovasculare Cardiovascular system Systema lymphoideum Lymphoid system Bibliographic Reference Citation: FIPAT. Terminologia Embryologica. 2nd ed. FIPAT.library.dal.ca. Federative International Programme for Anatomical Terminology, February 2017 Published pending approval by the General Assembly at the next Congress of IFAA (2019) Creative Commons License: The publication of Terminologia Embryologica is under a Creative Commons Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0) license The individual terms in this terminology are within the public domain. Statements about terms being part of this international standard terminology should use the above bibliographic reference to cite this terminology. The unaltered PDF files of this terminology may be freely copied and distributed by users. IFAA member societies are authorized to publish translations of this terminology. Authors of other works that might be considered derivative should write to the Chair of FIPAT for permission to publish a derivative work. Caput V: ORGANOGENESIS Chapter 5: ORGANOGENESIS
    [Show full text]
  • Anatomy and Physiology of Hair
    Chapter 2 Provisional chapter Anatomy and Physiology of Hair Anatomy and Physiology of Hair Bilgen Erdoğan ğ AdditionalBilgen Erdo informationan is available at the end of the chapter Additional information is available at the end of the chapter http://dx.doi.org/10.5772/67269 Abstract Hair is one of the characteristic features of mammals and has various functions such as protection against external factors; producing sebum, apocrine sweat and pheromones; impact on social and sexual interactions; thermoregulation and being a resource for stem cells. Hair is a derivative of the epidermis and consists of two distinct parts: the follicle and the hair shaft. The follicle is the essential unit for the generation of hair. The hair shaft consists of a cortex and cuticle cells, and a medulla for some types of hairs. Hair follicle has a continuous growth and rest sequence named hair cycle. The duration of growth and rest cycles is coordinated by many endocrine, vascular and neural stimuli and depends not only on localization of the hair but also on various factors, like age and nutritional habits. Distinctive anatomy and physiology of hair follicle are presented in this chapter. Extensive knowledge on anatomical and physiological aspects of hair can contribute to understand and heal different hair disorders. Keywords: hair, follicle, anatomy, physiology, shaft 1. Introduction The hair follicle is one of the characteristic features of mammals serves as a unique miniorgan (Figure 1). In humans, hair has various functions such as protection against external factors, sebum, apocrine sweat and pheromones production and thermoregulation. The hair also plays important roles for the individual’s social and sexual interaction [1, 2].
    [Show full text]
  • Hair Histology As a Tool for Forensic Identification of Some Domestic Animal Species
    EXCLI Journal 2018;17:663-670 – ISSN 1611-2156 Received: June 28, 2018, accepted: July 02, 2018, published: July 06, 2018 Original article: HAIR HISTOLOGY AS A TOOL FOR FORENSIC IDENTIFICATION OF SOME DOMESTIC ANIMAL SPECIES Yasser A. Ahmed1, Safwat Ali2, Ahmed Ghallab3* 1 Department of Histology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt 2 Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Minia University, Minia, Egypt 3 Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt * Corresponding author: E-mail: [email protected] http://dx.doi.org/10.17179/excli2018-1478 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/). ABSTRACT Animal hair examination at a criminal scene may provide valuable information in forensic investigations. How- ever, local reference databases for animal hair identification are rare. In the present study, we provide differential histological analysis of hair of some domestic animals in Upper Egypt. For this purpose, guard hair of large rumi- nants (buffalo, camel and cow), small ruminants (sheep and goat), equine (horse and donkey) and canine (dog and cat) were collected and comparative analysis was performed by light microscopy. Based on the hair cuticle scale pattern, type and diameter of the medulla, and the pigmentation, characteristic differential features of each animal species were identified. The cuticle scale pattern was imbricate in all tested animals except in donkey, in which coronal scales were identified. The cuticle scale margin type, shape and the distance in between were characteristic for each animal species.
    [Show full text]
  • Nail Anatomy and Physiology for the Clinician 1
    Nail Anatomy and Physiology for the Clinician 1 The nails have several important uses, which are as they are produced and remain stored during easily appreciable when the nails are absent or growth. they lose their function. The most evident use of It is therefore important to know how the fi ngernails is to be an ornament of the hand, but healthy nail appears and how it is formed, in we must not underestimate other important func- order to detect signs of pathology and understand tions, such as the protective value of the nail plate their pathogenesis. against trauma to the underlying distal phalanx, its counterpressure effect to the pulp important for walking and for tactile sensation, the scratch- 1.1 Nail Anatomy ing function, and the importance of fi ngernails and Physiology for manipulation of small objects. The nails can also provide information about What we call “nail” is the nail plate, the fi nal part the person’s work, habits, and health status, as of the activity of 4 epithelia that proliferate and several well-known nail features are a clue to sys- differentiate in a specifi c manner, in order to form temic diseases. Abnormal nails due to biting or and protect a healthy nail plate [1 ]. The “nail onychotillomania give clues to the person’s emo- unit” (Fig. 1.1 ) is composed by: tional/psychiatric status. Nail samples are uti- • Nail matrix: responsible for nail plate production lized for forensic and toxicology analysis, as • Nail folds: responsible for protection of the several substances are deposited in the nail plate nail matrix Proximal nail fold Nail plate Fig.
    [Show full text]
  • Expression of Integrins and Basement Membrane Components by Wound Keratinocytes
    Expression of integrins and basement membrane components by wound keratinocytes. H Larjava, … , R H Kramer, J Heino J Clin Invest. 1993;92(3):1425-1435. https://doi.org/10.1172/JCI116719. Research Article Extracellular matrix proteins and their cellular receptors, integrins, play a fundamental role in keratinocyte adhesion and migration. During wound healing, keratinocytes detach, migrate until the two epithelial sheets confront, and then regenerate the basement membrane. We examined the expression of different integrins and their putative ligands in keratinocytes during human mucosal wound healing. Migrating keratinocytes continuously expressed kalinin but not the other typical components of the basement membrane zone: type IV collagen, laminin, and type VII collagen. When the epithelial sheets confronted each other, these missing basement membrane components started to appear gradually through the entire wound area. The expression of integrin beta 1 subunit was increased in keratinocytes during migration. The beta 1-associated alpha 2 and alpha 3 subunits were expressed constantly by wound keratinocytes whereas the alpha 5 subunit was present only in keratinocytes during reepithelialization. Furthermore, migrating cells started to express alpha v-integrins which were not present in the nonaffected epithelium. All keratinocytes also expressed the alpha 6 beta 4 integrin during migration. In the migrating cells, the distribution of integrins was altered. In normal mucosa, beta 1-integrins were located mainly on the lateral plasma membrane and alpha 6 beta 4 at the basal surface of basal keratinocytes in the nonaffected tissue. In wounds, integrins were found in filopodia of migrating keratinocytes, and also surrounding cells in […] Find the latest version: https://jci.me/116719/pdf Expression of Integrins and Basement Membrane Components by Wound Keratinocytes Hannu Lariava, * Tuula Salo,t Kirsi Haapasalmi, * Randall H.
    [Show full text]
  • Corrective Gene Transfer of Keratinocytes from Patients with Junctional Epidermolysis Bullosa Restores Assembly of Hemidesmosomes in Reconstructed Epithelia
    Gene Therapy (1998) 5, 1322–1332 1998 Stockton Press All rights reserved 0969-7128/98 $12.00 http://www.stockton-press.co.uk/gt Corrective gene transfer of keratinocytes from patients with junctional epidermolysis bullosa restores assembly of hemidesmosomes in reconstructed epithelia J Vailly1, L Gagnoux-Palacios1, E Dell’Ambra2, C Rome´ro1, M Pinola3, G Zambruno3, M De Luca2,3 J-P Ortonne1,4 and G Meneguzzi1 1U385 INSERM, Faculte´ de Me´decine, Nice; 4Service de Dermatologie, Hoˆpital L’Archet, Nice, France; Laboratories of 2Tissue Engineering and 3Molecular and Cell Biology, Istituto Dermopatico dell’Immacolata, Rome, Italy Herlitz junctional epidermolysis bullosa (H-JEB) provides deposited into the extracellular matrix. Re-expression of a promising model for somatic gene therapy of heritable laminin-5 induced cell spreading, nucleation of hemides- mechano-bullous disorders. This genodermatosis is mosomal-like structures and enhanced adhesion to the cul- caused by the lack of laminin-5 that results in absence of ture substrate. Organotypic cultures performed with the hemidesmosomes (HD) and defective adhesion of squam- transduced keratinocytes, reconstituted epidermis closely ous epithelia. To establish whether re-expression of lami- adhering to the mesenchyme and presenting mature hemi- nin-5 can restore assembly of the dermal-epidermal attach- desmosomes, bridging the cytoplasmic intermediate fila- ment structures lacking in the H-JEB skin, we corrected the ments of the basal cells to the anchoring filaments of the genetic mutation hindering expression of the ␤3 chain of basement membrane. Our results provide the first evi- laminin-5 in human H-JEB keratinocytes by transfer of a dence of phenotypic reversion of JEB keratinocytes by laminin ␤3 transgene.
    [Show full text]
  • Nestin Expression in Hair Follicle Sheath Progenitor Cells
    Nestin expression in hair follicle sheath progenitor cells Lingna Li*, John Mignone†, Meng Yang*, Maja Matic‡, Sheldon Penman§, Grigori Enikolopov†, and Robert M. Hoffman*¶ *AntiCancer, Inc., 7917 Ostrow Street, San Diego, CA 92111; †Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724; §Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307; and ‡Stony Brook University, Stony Brook, NY 11794 Contributed by Sheldon Penman, June 25, 2003 The intermediate filament protein, nestin, marks progenitor expression of the neural stem cell protein nestin in hair follicle cells of the CNS. Such CNS stem cells are selectively labeled by stem cells suggests a possible relation. placing GFP under the control of the nestin regulatory se- quences. During early anagen or growth phase of the hair Materials and Methods follicle, nestin-expressing cells, marked by GFP fluorescence in Nestin-GFP Transgenic Mice. Nestin is an intermediate filament nestin-GFP transgenic mice, appear in the permanent upper hair (IF) gene that is a marker for CNS progenitor cells and follicle immediately below the sebaceous glands in the follicle neuroepithelial stem cells (5). Enhanced GFP (EGFP) trans- bulge. This is where stem cells for the hair follicle outer-root genic mice carrying EGFP under the control of the nestin sheath are thought to be located. The relatively small, oval- second-intron enhancer are used for studying and visualizing shaped, nestin-expressing cells in the bulge area surround the the self-renewal and multipotency of CNS stem cells (5–7). hair shaft and are interconnected by short dendrites. The precise Here we report that hair follicle stem cells strongly express locations of the nestin-expressing cells in the hair follicle vary nestin as evidenced by nestin-regulated EGFP expression.
    [Show full text]
  • Neural Control of Facial Sweat Gland Secretion in Horses
    Iowa State University Capstones, Theses and Creative Components Dissertations Fall 2019 Neural control of facial sweat gland secretion in horses Lu Liu Follow this and additional works at: https://lib.dr.iastate.edu/creativecomponents Part of the Comparative and Evolutionary Physiology Commons, and the Systems and Integrative Physiology Commons Recommended Citation Liu, Lu, "Neural control of facial sweat gland secretion in horses" (2019). Creative Components. 455. https://lib.dr.iastate.edu/creativecomponents/455 This Creative Component is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Creative Components by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Neural control of facial sweat gland secretion in horses Lu Liu 2019.11.26 BMS 599 Creative Component Biomedical Sciences Department Iowa State University Abstract: For sweat glands, it has been shown that sympathetic neurons express a cholinergic/noradrenergic co-phenotype in their innervation in the trunk of mice.(Schütz et al. 2008). It is unknown if facial sweat glands are innervated the same way. Gustatory sweating is an abnormal sweating condition. People can sweat profusely when eating or drinking, or even thinking about eating or drinking. We hypothesize that the facial sweat glands are controlled differently and can be related to parasympathetic neurons from cranial nerves. Some samples from human donors have been tested, but few sweat glands can be targeted since the donors were older people. Thus, it was decided to use horse tissue for this project to obtain greater numbers of sweat glands on the face.
    [Show full text]
  • Periodic Acid-Schiff Positive Material Accumulating Within the Lumen of Eccrine Sweat Glands*
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector PERIODIC ACID-SCHIFF POSITIVE MATERIAL ACCUMULATING WITHIN THE LUMEN OF ECCRINE SWEAT GLANDS* GEORGE W. HAMBRICK, JR., M.D. The purpose of this paper is to record findings with regard to diastase-resistant, periodic acid-Schiff positive material in the lumen of eccrine ducts and glands of two individuals. This material has two possible sources in the normal eccrine sweat gland, namely, the cuticle lining of the eccrine duct and the cells of the secretory tubule. Holyoke and Lobits (3) studying 35 normal skin biopsies re- B pp HI D FIG. 1. A. Vertical section through skin of the control area showing dilatation of an eccrine sweat duct with eosinophilic material in the lumen. H. and E., X178. B. Same find- ings as in A above from an area treated daily with 3 per cent hexachloronaphthalene in acetone for one week, Xl7S. C. Section through dermal parts of eccrine duct containing a cast. H. and E., X355. D. Section through dermal eccrine duct containing periodic acid- Schiff positive material in the lumen, X660. *Fromthe Department of Dermatology (Donald M. Pillsbury, M.D., Director), School of Medicine, University of Pennsylvania, Philadelphia 4, Pennsylvania. This study was supported by U. S. Army grant DA-49-007-MD-154. Received for publication March 29, 1957. 213 214 THF JOURNAL OF INVESTIGATIVE DERMATOLOGY ported the presence of material in the lumen of the eccrine duct and gland; they classified the material as amorphous, cast, cellular or bacterial.
    [Show full text]
  • Apocrine Sweat Retention in Man I
    CORE Metadata, citation and similar papers at core.ac.uk Provided by Elsevier - Publisher Connector APOCRINE SWEAT RETENTION IN MAN I. EXPERIMENTAL PRODUCTION OF ASYMPTOMATIC FORM*, I. HARRYJ. HTJRLEY, JR.,M.D.ANnWALTERB. SHELLEY, M.D., PH.D. Within recent years, the concept of poral closure and the effects of such an obstructive process on the eccrine sweat gland have been clearly defined (1, 2). The pathogenesis of the various sweat retention syndromes is now more fully understood. Moreover, the need for further study of the "blockage factor" in the diseases of the other glandular appendages has been emphasized. Much attention has been paid to the sebaceous gland in this respect (3). Follicular occlusion has been long regarded as one of the essential phases in the development of the acneiform dermatoses. In contrast, however, the possible role of ductal obstruction and consequent sweat retention in the diseases of the apocrine sweat gland has received little mention in the literature. Yet an examination of the clinical features of the apocrine disorders indicates that poral occlusion may be of considerable signifi- cance in their pathogenesis. This series of investigations was undertaken in an effort to define the effects of ductal closure on the human apocrine sweat gland. METHOD AND MATERIALS Seven healthy adult white males between the ages of 20 and 28 were selected for this study. Antiperspirants had been interdicted for at least one month. The axillae of these subjects were shaved and the apocrine sweat glands emptied by the local subcutaneous injection of 0.15 cc. 1:1000 epinephrine so- lution.
    [Show full text]
  • The Integumentary System, but Shares Some of Skin’S Properties
    PowerPoint® Lecture Slides The Skin and the Hypodermis prepared by Leslie Hendon University of Alabama, Birmingham • Skin—our largest organ • Accounts for 7% of body weight • Varies in thickness from 1.5–4.4mm C H A P T E R 5 • Divided into two distinct layers • Epidermis The • Dermis Integumentary • Hypodermis—lies deep to the dermis • Composed of areolar and adipose tissues System • Not part of the integumentary system, but shares some of skin’s properties Copyright © 2011 Pearson Education, Inc. Copyright © 2011 Pearson Education, Inc. Skin Structure The Skin and Hypodermis • Functions 1. Protection—cushions organs and protects from Hair shaft bumps, chemicals, water loss, UV radiation Dermal papillae Epidermis Subpapillary vascular 2. Regulation of body temperature---Capillary Papillary plexus network and sweat glands regulate heat loss layer Pore Appendages of skin 3. Excretion—urea, salts, and water lost through Dermis Reticular Eccrine sweat gland sweat layer Arrector pili muscle Sebaceous (oil) gland Hair follicle 4. Production of vitamin D---Epidermal cells use Hair root UV radiation to synthesize vitamin D Hypodermis (superficial fascia) 5. Sensory reception—Contains sense organs Nervous structures Sensory nerve fiber Dermal vascular plexus associated with nerve endings Lamellar (Pacinian) corpuscle Adipose tissue Hair follicle receptor (root hair plexus) Copyright © 2011 Pearson Education, Inc. Figure 5.1 Copyright © 2011 Pearson Education, Inc. Figure 5.2 Gross structure of skin and underlying tissues. Epidermis • Is composed of keratinized stratified squamous epithelium • Contains four main cell types • Keratinocytes • Location—stratum spinosum; produce keratin a fibrous protein Epidermis • Melanocytes • Location—basal layer; manufacture and secrete the pigment melanin Dermis • Tactile epithelial cells (Merkel cells) Hypodermis • Location—basal layer; attached to sensory nerve endings Deep fascia • Dendritic cells (Langerhans cells) • Location—stratum spinosum; part of immune system; Muscle macrophage-like Copyright © 2011 Pearson Education, Inc.
    [Show full text]