PHARM 120: Human Anatomy and Physiology for Pharmacy 1 - Integumentary System PDF

PHARM 120: Human Anatomy and Physiology for Pharmacy 1 INTEGUMENTARY SYSTEM Jarvin Enosh T. Tan & Maria Patricia S. Ugalde Week 4 HAIR TYPES....................................................... 9...

PHARM 120: Human Anatomy and Physiology for Pharmacy 1 INTEGUMENTARY SYSTEM Jarvin Enosh T. Tan & Maria Patricia S. Ugalde Week 4 HAIR TYPES....................................................... 9 OUTLINE HAIR GROWTH................................................... 9 SKIN GLANDS.........................................................10 DEFINITION OF TERMS........................................... 1 TWO MAIN TYPES OF SUDORIFEROUS FUNCTIONS OF THE SKIN.......................................2 GLANDS............................................................ 10 THERMOREGULATION...................................... 2 ANATOMICAL PARTS OF NAILS...........................10 BLOOD RESERVOIR.......................................... 2 FUNCTIONS OF NAILS...........................................11 PROTECTION..................................................... 2 NAIL GROWTH........................................................11 CUTANEOUS SENSATIONS...............................2 SKIN DISORDERS/CONDITIONS........................... 11 EXCRETION AND ABSORPTION.......................2 PSORIASIS........................................................11 EXCRETION................................................. 2 PSORIATIC ARTHRITIS....................................12 ABSORPTION...............................................2 ALBINISM.......................................................... 12 SYNTHESIS OF VITAMIN D................................3 VITILIGO............................................................13 MAIN LAYERS OF THE SKIN................................... 3 ACNE................................................................. 13 EPIDERMIS......................................................... 3 VERNIX CASEOSA........................................... 13 TYPES OF EPIDERMAL CELLS.................. 4 MILIA................................................................. 13 EPIDERMAL LAYERS......................................... 4 SEBORRHEA.................................................... 13 STRATUM BASALE/STRATUM MOLES.............................................................. 14 GERMINATIVUM...........................................4 SKIN CANCER.................................................. 14 STRATUM SPINOSUM................................. 4 BASAL CELL CARCINOMA........................14 STRATUM GRANULOSUM.......................... 4 SQUAMOUS CELL CARCINOMA.............. 14 STRATUM LUCIDUM.................................... 5 MALIGNANT MELANOMA..........................14 STRATUM CORNEUM..................................5 RINGWORM...................................................... 14 EPIDERMAL RIDGES......................................... 5 CELLULITIS.......................................................15 DERMIS............................................................... 5 COMMON WARTS............................................ 15 PAPILLARY REGION/LAYER.............................. 5 COLD SORES................................................... 15 RETICULAR REGION/LAYER.............................5 SHINGLES.........................................................15 HYPODERMIS.....................................................6 IMPETIGO......................................................... 15 THE SKIN AS ROUTE OF ADMINISTRATION......... 6 LESION..............................................................16 PIGMENTS THAT IMPART COLOR TO THE SKIN.. 6 LESION SIZES............................................16 MELANIN............................................................. 6 BLISTER............................................................ 16 CAROTENE......................................................... 6 CALLUS............................................................. 16 HEMOGLOBIN.................................................... 6 CORNS.............................................................. 17 SKIN COLOR AND CLUES.......................................6 BURNS.............................................................. 17 CYANOSIS...........................................................6 PRESSURE ULCERS....................................... 17 JAUNDICE........................................................... 6 SKIN WOUND HEALING.........................................17 ERYTHEMA......................................................... 7 EPIDERMAL WOUND HEALING...................... 17 PALLOR OR BLANCHING...................................7 DEEP WOUND HEALING................................. 18 BLACK AND BLUE MARKS OR BRUISES......... 7 INFLAMMATORY PHASE........................... 18 TATTOOING AND BODY PIERCING.........................7 MIGRATORY PHASE..................................18 STRUCTURAL AND FUNCTIONAL TYPES OF PROLIFERATIVE PHASE........................... 18 SKIN...........................................................................7 MATURATION PHASE................................ 18 THE HAIR.................................................................. 7 INTEGUMENTARY SYSTEM DEVELOPMENT...... 18 DISTRIBUTION OF HAIR.................................... 7 SKIN ANTI-AGING PROCEDURES.........................18 FUNCTIONS OF HAIR........................................ 7 ANATOMY OF HAIR............................................8 HAIR CHEMISTRY.....................................................8 DEFINITION OF TERMS PROPERTIES OF HAIR...................................... 8 System BS PHARMACY ‘22 PHARM 120 1  o A group of organs working together to o Alert the immune system to the presence of perform specific activities. potentially harmful microbial invaders by Integumentary System recognizing and processing them o Composed of the skin and its accessory Macrophages in the dermis structures, hair and nails, along with various o Phagocytize bacteria and viruses that glands, muscles, and nerves. manage to bypass the dendritic cells. o From the words in-, meaning inward, and -tegere, meaning to cover CUTANEOUS SENSATIONS Dermatology Contains sensory nerve endings o The medical specialty that deals with the Sensations that arise from the skin structure, function, and disorders of the o Tactile sensations (touch, pressure, integumentary system. vibration, tickling) ▪ For the diagnosis and treatment of skin o Thermal sensations (warmth and coolness) disorders o Pain Skin o Also known as the cutaneous membrane; Table 1. Integumentary Structures that aid in covers the external surface of the body Sensation o Largest organ of the body in surface area (2m2) and weight (4.5 to 5 kg) Example Location o About 7% of the total body weight Nonencapsulated Epidermis sensory corpuscles FUNCTIONS OF THE SKIN THERMOREGULATION Tactile corpuscles Dermis Homeostatic methods of regulation of body of Lamellar corpuscles Dermis and temperature: subcutaneous tissue o Liberating sweat its surface o Adjusting the flow of blood in the dermis Hair root plexuses Hair follicle (around each) High environmental temperature or heat produced by exercise o Response: sweat production and dilation of EXCRETION AND ABSORPTION blood vessels in the skin EXCRETION o Evaporation of sweat helps lower body Stratum corneum, despite being waterproof: temperature o About 400 mL of water evaporates through o Dilation increases blood flow it daily. Low environmental pressure response: o A sedentary person loses additional 200mL o Production of sweat from eccrine glands is per day as sweat; a physically active person decreased loses much more. o Blood vessels constrict Sweat o Removes water and heat from the body BLOOD RESERVOIR o It is the vehicle for excretion of small The dermis houses an extensive network of amounts of salts, carbon dioxide, and two blood vessels that carry 8–10% of the total organic molecules that result from the blood flow in a resting adult. breakdown of proteins—ammonia and urea. PROTECTION ABSORPTION Water-soluble substances and materials Keratin o Absorption is negligible o Protects underlying tissues Lipid-soluble substances and materials Lipid o Fat-soluble vitamins (A, D, E, K) o Released by lamellar granules that retard o Certain drugs evaporation of water from the skin surface o Oxygen and carbon dioxide Sebum Toxic materials o Protects skin and hairs from drying out and o Organic solvents (e.g. acetone in some nail contains bactericidal chemicals polish removers) Acidic pH of perspiration o Salts of heavy metals (e.g. Pb, Hg, As) o Retards the growth of microbes o Substances in poison ivy and poison oak Melanin Topical steroids o Provides protection against the damaging o Topical steroids (e.g. cortisone) move easily effects of UV light to the papillary region of the dermis Dendritic cells of the epidermis BS PHARMACY ‘22 PHARM 120 2  o Certain drugs that are absorbed by the skin may be administered by applying adhesive patches SYNTHESIS OF VITAMIN D Requires activation of precursor molecule in the skin by UV rays in sunlight (UVB; wavelengths of 290 to 315 nm) Only a small amount of exposure to UV light (about 10-15 minutes at least twice a week) is required for vitamin D synthesis. Vitamin D Aids in calcium absorption Most potent and active form of vitamin D Calcitriol A hormone that aids in the absorption of calcium from foods in the gastrointestinal tract into the blood. Calcidiol Major circulating form of vitamin D Immune Response: o Most cells of the immune system have vitamin D receptors, and the cells activate vitamin D in response to an infection, (e.g. respiratory infection such as influenza) o Vitamin D is believed to: ▪ Enhance phagocytic activity ▪ Increase the production of antimicrobial Figure 1 and 2. Vitamin D Synthesis in the Body substances in phagocytes ▪ Regulate immune functions MAIN LAYERS OF THE SKIN ▪ Help reduce inflammation EPIDERMIS Superficial, thinner portion of skin Composed of epithelial tissue: keratinized stratified squamous epithelium Figure 3. Main Layers of the Epidermis Keratinization: accumulation of more keratin by newly formed cells in the stratum basale as they are slowly pushed to the surface Rate of cell division increases in stratum basale when outer layers of the epidermis are stripped away Epidermal growth factor (EGF): hormonelike proteins that play a role in epidermal growth mechanisms such as epidermal wound healing BS PHARMACY ‘22 PHARM 120 3  TYPES OF EPIDERMAL CELLS EPIDERMAL LAYERS Keratinocytes Most regions of the body has 4 epidermal ○ 90% epidermal cells layers ○ arranged in 4 to 5 layers, and produces In areas where exposure to friction is greatest, keratin such as in the fingertips, palms, and soles, keratin: tough, fibrous protein that helps there are 5 epidermal layers protect the skin and underlying tissues The skin layers from top to base of epidermis from heat, microbes, and chemicals are: ○ produces lamellar granules ○ Stratum corneum lamellar granules: release a ○ Stratum lucidum water-repellent sealant ○ Stratum granulosum Melanocytes ○ Stratum spinosum ○ 8% epidermal cells ○ Stratum basale ○ Migrate from the ectoderm of a developing embryo and produces melanin STRATUM BASALE/STRATUM brown-black pigment that contributes to GERMINATIVUM the skin color and absorbs damaging Basal = base UV light Deepest layer of the epidermis shields the nuclear DNA from being Composed of a single row of cuboidal or damaged by UV light columnar keratinocytes/ emphasizes its role in susceptible to damage by UV light forming new cells Some cells are stem cells that undergo cell division to continually produce new keratinocytes Cytoskeletons within keratinocytes of this layer includes tonofilaments ○ Scattered intermediate filaments ○ Composed of a protein that will later form the keratin in more superficial epidermal layers STRATUM SPINOSUM ○ Spinos- = thornlike ○ Superficial to the stratum basale, where 8 to 10 layers of many-sided keratinocytes fit closely Figure 4. Presence of Keratinocytes and together Melanocytes in Epidermis ○ Bundles of tonofilaments are inserting into the desmosome that allows tightly joining the cells Langerhans cells to one another ○ Dendritic cells ○ Arise from red bone marrow and migrate to STRATUM GRANULOSUM epidermis, where they constitute small Granulos = little grains fraction of epidermal cells Consists of 3 to 5 layers of flattened ○ Participate in immune responses mounted keratinocytes that undergoing apoptosis against microbes that invade the skin; 2 types of granules in the stratum granulosum: easily damaged by UV ○ Keratohyalin: darkly staining granules of a ○ Role of Langerhans cells: help other cells of protein which converts the tonofilaments the immune system recognize an invading into keratin; distinctive feature of cells in this microbe and destroy it layer Merkel cells ○ Lamellar granules: membrane-enclosed ○ Least numerous of the epidermal cells granules found in the keratinocytes which ○ Located at the deepest layer of the release a lipid-rich secretion epidermis Lipid-rich secretion is deposited in ○ Contact the flattened process of a sensory stratum corneum, lucidum, and neuron, the tactile Merkel discs granulosum ○ Detect different aspects of touch sensations Transition between deeper, metabolically active with tactile (Merkel) disc or strata and the dead cells of the more superficial nonencapsulated sensory corpuscle strata BS PHARMACY ‘22 PHARM 120 4  STRATUM LUCIDUM DERMIS lucid = clear Second, deeper part of the skin which is Present only in thick skin of the fingertips, composed mainly of connective tissue palms, and soles containing collagen and elastic fibers Consists of 3 to 5 layers of flattened, clear, ○ Due to this structural characteristics, it has dead keratinocytes that contain large amounts great tensile strength and has the ability to of keratin and thickened plasma membranes stretch and recoil easily Probably provides an additional level of The dermis is much thicker than the epidermis toughness in this region of thick skin and varies from region to region in the body The dermis is composed of 2 regions and 1 STRATUM CORNEUM special region*: Corne- = horn/horny ○ Papillary region/layer Consists of 25 to 30 layers of flattened dead ○ Reticular region/layer keratinocytes which are continuously shed and ○ Epidermal ridges* replaced by cells from the deeper strata It multiple layers of dead cells help to protect PAPILLARY REGION/LAYER deeper layers from injury and microbial Superficial part of the dermis and comprises invasions one-fifth (⅕) of the thickness of the total dermis Constant exposure of skin to friction stimulates Its structural component consists of areolar the formation of callus connective tissues containing fine elastic fibers ○ callus: abnormal thickening of the stratum The surface area of papillary layer is greatly corneum increased by the dermal papillae ○ Dermal papillae are small, finger-like (sometimes described as nipple-like) projections that project into the undersurface of the skin ○ All dermal papillae contain capillary loops or blood vessels ○ Some dermal papillae contain tactile corpuscles of Meissner corpuscles which are nerve endings sensitive to touch. ○ Some dermal papillae may also contain free nerve endings which are dendrites that lack structural specialization These free nerve endings initiate signals that allow for sensations such as warmth, coolness, pain, tickling, and Figure 5. Epidermal layers and epidermal cells itching EPIDERMAL RIDGES RETICULAR REGION/LAYER Series of grooves and ridges on the surfaces of Deepest part of the dermis the palms, fingers, toes, and soles Its structural component consists of dense Develop during the 3rd and 4th fetal months irregular connective tissue containing bundles ○ Follows the contours of the dermal papillae of collagen and some coarse elastic fibers found in the papillary region/layer ○ Due to this structural characteristics, Increase surface area of the epidermis, particularly the presence of collagen and increasing grip of the hand or foot by increasing elastic fibers, it provides the skin: friction Strength Form fingerprints and footprints Extensibility (ability to stretch) Genetically determined and is unique for every Elasticity (ability to return to original individual shape after stretching) Pattern does not change during life, only On deeper parts of the reticular region, some enlarges adipose cells are present ○ Hence, a good basis for identification Collagen fibers in the reticular region are more through fingertips or footprints organized than in the papillary dermis Dermatoglyphics: study of pattern of When the skin is overstretched, striae (stretch epidermal ridges marks) may form which is a result of the disruption of the lateral bonding between collagen fibers BS PHARMACY ‘22 PHARM 120 5  ○ This leads to small dermal blood vessel ○ Melanocytes are abundant in the epidermis rupture which is why stretch marks initially of the penis, nipples of the breast, area just appear reddish around the nipples (areolae), face, and limbs; also present in mucous membranes HYPODERMIS Amount is about the same in all people Not really part of the skin; also known as Differences in skin color are due mainly subcutaneous tissue to the amount of pigment the Layer that separates the muscle from the skin melanocytes produce and disperse to Consists of areolar and adipose tissue keratinocytes ○ Due to this structural characteristics, it Synthesized from the amino acid, tyrosine, in serves as a storage depot for fat and the presence of the enzyme called tyrosinase contains large blood vessels that supply the Synthesis occurs in an organelle called skin melanosome This area also contains nerve endings known Exposure to UV light increases enzymatic as lamellar corpuscles or pacinian corpuscles activity within melanosomes which in turn leads ○ These corpuscles are sensitive to pressure to melanin production causing an increased amount and darkness of melanin THE SKIN AS ROUTE OF ADMINISTRATION ○ Phenomenon known as suntanning Freckles: Accumulation of melanin in patches The skin serves as one of the numerous routes Age (liver) Spots: Flat blemishes that look like for a drug to be administered in the body freckles and range in color from light brown to For creams, oils, and pastes, they are black; accumulations of melanin commonly topically administered As for parenteral administration via injection, the skin serves as the location for four types of CAROTENE administration: A yellow-orange pigment, precursor of vitamin ○ Intramuscular (injection at 90o to target A, which is used to synthesize pigments muscles) needed for vision ○ Subcutaneous (injection at 45o to target ○ Found in the stratum corneum and fatty hypodermis or subcutaneous tissue) areas of the dermis and subcutaneous layer ○ Intravenous (injection at 25o to target veins Excess intake of carotene-rich foods turns the in dermis) skin color to orange, especially for light-skinned ○ Intradermal (injection at 10o-15o to target the individuals dermis) HEMOGLOBIN Oxygen-carrying red pigment inside RBCs ○ Skin of white people appear pink or red, depending on the amount and oxygen content of the blood moving through capillaries in the dermis SKIN COLOR AND CLUES As an organ that is partly external, the skin color can provide insight into different physiological illnesses that a person may have CYANOSIS Figure 6. Different Injection Techniques Bluish coloration (nail beds, skin, mucous membranes - lips, gums, tongue) PIGMENTS THAT IMPART COLOR TO THE Poorly oxygenated hemoglobin SKIN Heart failure & severe breathing disorders There are 3 key pigments that impart color to the skin: JAUNDICE ○ Melanin Due to a buildup of the yellow pigment bilirubin ○ Carotene in the blood ○ Hemoglobin Gives a yellowish appearance to the whites of the eyes & the skin MELANIN Usually indicates liver disease Causes the skin’s color to vary from pale yellow to tan to black BS PHARMACY ‘22 PHARM 120 6  ERYTHEMA soles Redness of the skin Caused by engorgement of capillaries in the Stratum lucidum Thick strata lucidum, dermis with blood due to skin injury, exposure essentially lacking; spinosum and corneum to heat, infection, inflammation, or allergic thinner strata spinosum reactions and corneum PALLOR OR BLANCHING Lacking epidermal Epidermal ridges are Pale skin ridges due to poorly present due to May signify certain types of emotional stress developed and fewer well-developed and (fear, anger), anemia, low blood pressure, or dermal papillae more numerous dermal impaired blood flow into the area papillae Hair follicles and No hair follicles, BLACK AND BLUE MARKS OR BRUISES arrector pili, and arrector pili muscles, Reveal sites where blood has escaped from the sebaceous glands are and sebaceous glands circulation & has clotted in the tissue spaces present Clotted blood masses (hematomas) May signify a deficiency of vitamin C in the diet Fewer sudoriferous More numerous sweat or bleeder’s disease glands and sparser glands and denser sensory receptors sensory receptors TATTOOING AND BODY PIERCING Tattooing is a permanent coloration of the skin THE HAIR in which a foreign pigment is deposited with a needle into macrophages in the dermis Can also be called as “pili” ○ Stability of dermis makes the tattoo Hairs are growths of epidermis composed of permanent dead, keratinized epidermal cells. ○ Fades over time due to exposure to subligh, improper healing, picking scabs, and DISTRIBUTION OF HAIR flushing away of ink particles by the Most skin surfaces except the palms, palmar lymphoid system surface of fingers, soles, plantar surface of feet. Laser tattoo removal uses concentrated beams Scalp, eyebrows, axillae, and around the of light that dissolves the globules of ink in the external genitalia, chest and legs (in men), face macrophages leading to easier removal via Genetic and hormonal influences determine lymphatic system hair thickness and the pattern of distribution ○ Needs time and money investment and symptoms of removal include pain, scarring, FUNCTIONS OF HAIR and discoloration of skin Protection Body piercing refers to insertion of jewelry ○ Scalp hair from injury and the sun’s rays through an artificial opening ○ Decreased heat loss from the scalp ○ Total healing of piercing may take up of ○ Eyebrows/eyelashes from perspiration year Light touch ○ Could disrupt certain medical procedures ○ Touch receptors associated with hair hence it is removed prior to certain medical follicles are activated whenever a hair is procedures moved even slightly Identification STRUCTURAL AND FUNCTIONAL TYPES Seduction OF SKIN Shown below is the 2 types of skin according to structure and function Table 2. Skin Classification based on Structure and Function Thin Skin Thick Skin All parts of the body Distributed in the except palms, palmar palms, palmar surface surfaces of digits, and of digits, and soles BS PHARMACY ‘22 PHARM 120 7  ANATOMY OF HAIR ○ Provides nourishment to hair through areolar connective tissue and blood vessels. Arrector pili ○ Smooth muscle that extends from the superficial dermis of the skin to the side of hair follicle ○ “Goosebumps or gooseflesh” Hair root plexus ○ Dendrites of neurons that surround each hair follicle ○ Generate nerve impulses if their hair shafts are moved Sebaceous or oil glands ○ Individual hair’s well of natural oil ○ Dry or greasy hair HAIR CHEMISTRY Keratin ○ soft substance arising from hair follicle ○ hardens as it rises up and out into the shaft ○ insoluble, very tough, highly elastic Melanin ○ corresponds to hair color Figure 7. Parts of the Hair ○ is determined by genetics Hair shaft ○ mixture and shades vary from person to ○ Superficial portion of the hair; projects from person the surface of the skin. ○ the distribution of melanin is across the Hair root scalp ○ Deep to the shaft ○ Eumelanin: ○ Penetrates into the dermis, and sometimes dark pigment, for black and brunette into the subcutaneous layers hair; more Eumelanin = darker hair 3 layers of hair shaft and root: ○ Phaeomelanin ○ Cuticle lighter pigment, for red and blond hair Thinnest and outermost Hair color ranges from yellow, brown, red, and Protective scale-like cells black Affected by chemical, physical, and ○ Gray hair thermal damage contains few melanin granules spread Heavily keratinized out through hair ○ Cortex ○ White Hair Middle determines absence of melanin 75-80% of hair’s protein structure whiteness of hair is just an optical Gives hair its strength and elasticity effect, it just means they cannot create Contains pigments that color hair melanin anymore in the body ○ Medulla it initially looks yellow, which is the Central axis “color” of keratin Column of soft keratinised cells interspersed with air pockets (helps give PROPERTIES OF HAIR hair its elasticity) Hair has optimum pH of 4.5-5.5 Hair follicle ○ Hair at optimum pH has a compact and ○ Surrounds the hair root constricted cuticle, positively charged, and Made up of an external root sheath and acidic an internal root sheath (collectively ○ At optimum pH, the hair protects the cortex, called the epithelial root sheath) imparts shen Hair bulb ○ Onion-shaped structure found at the base of each hair follicle Hair papilla ○ Housed by the hair bulb BS PHARMACY ‘22 PHARM 120 8  ○ African Black, can be tightly curled hair wooly and dry hair hair is extremely easily damaged by heat or chemicals Figure 10. Summary of Hair Types based on Ethnicities HAIR GROWTH ○ Grows at ~1 cm per month Figure 8. pH scale for Hair ○ Normal hair loss is approximately ~100 hairs per day HAIR TYPES ○ Rate of growth and replacement cycle Lanugo Hairs refers to illness, radiation therapy, ○ also known as downy hairs chemotherapy, age, genetics, gender and ○ they are fine, soft hair that develops on an severe emotional stress unborn baby at 3 months after conception hair loss is increased when rapid ○ they grow at the same rate and shed off 4 weight-loss and 3-4 months postpartum weeks before birth occur Types of scalp hair found in adults ○ Stages of Hair Growth is divided into anagen, ○ Vellus hairs catagen, and telogen short hairs with height of ~1-2 cm Anagen, also known as the active growth contains little or no pigment phase is where permanent hair removal is hair follicles with no oil glands and don’t possible grow other kinds of hair Cells from the hair matrix continuously ○ Terminal hairs divide and push upwards existing cells long hairs that are found on the head, of the hair root body, arms, and legs Hair cells that are being pushed upward has hair follicles with oil glands undergo keratinization and die ○ Catagen, also known as the transition or regression phase is where hair slowly move upwards towards the skin pore and away from the hair follicle Movement of hair away from blood supply causes the hair matrix to stop dividing and the follicle to shrink ○ Telogen, also known as resting phase, is where the dermal papilla fully separates from the follicle Figure 9. Types of Scalp Hair Hair Types based on Ethnic Differences **can differ and does not have be standardized ○ Asian has very straight hair, color is always black, resists damage well ○ Caucasian ○ either wavy or straight hair, color ranges from black to a pale blind that is almost white, can include all possible shades of hair color in Figure11. Stages of Hair Growth between BS PHARMACY ‘22 PHARM 120 9 ○ Abnormalities of Hair Growth Found mainly in the skin of the axilla, Hirsutism and Hypertrichosis groin, areolae, bearded regions of the Excessive, abnormal hairiness that can face in adult males be either localized or cover the entire “Cold sweat”: stimulated during body emotional stress and sexual excitement Result: persistence of lanugo-vellus Ceruminous Glands: modified sweat glands hairs in fetus or from augmented in the external ear which produce waxy development of hair follicles secretion Alopecia or Hair Loss Combined secretion of the ceruminous significant and persistent thinning of hair and sebaceous glands is called baldness: most common type cerumen or earwax (provides a sticky it genetically affects men and barrier that impedes the entrance of women foreign bodies) Men lose 25% of their hair above the forehead, and crown of head at age 25, and 50% at age 50 Note! Women lose their hair for the Initially, this sweat gland was thought to release second and third decades of life. secretions in an apocrine manner - by pinching In women, their hairline remains off one end of the cell, hence its name. It was intact with little or no loss of hair at eventually discovered that the secretions are the temple. released via exocytosis - the same mechanism as that of the eccrine sweat glands. Regardless, SKIN GLANDS the name apocrine sweat glands is retained until Sebaceous Glands/Oil Glands this day. ○ Simple, branched acinar glands ○ Most are connected to the hair follicles ANATOMICAL PARTS OF NAILS ○ Absent in the palms and soles ○ Large in the skin of breasts, face, nack, and Nail Body upper chest ○ Visible Part ○ Sebum: an oily substance which is a ○ Appears mostly pink (blood flowing through mixture of triglycerides, cholesterol, underlying capillaries) proteins, and inorganic salts Free edge Coats the surface of hairs and helps ○ Part that may extend past the distal end of keep them from drying and becoming the digit (a general term which refers to brittle both fingers and toes) white due to absence Prevents excessive evaporation of of capillaries water from the skin Nail root Keeps the skin soft and pliable ○ Portion that is buried in a fold of skin Inhibits the growth of certain bacteria Lunula (“little moon”) Sudoriferous Glands/Sweat Glands ○ Whitish, crescent-shaped area of the ○ 3-4 million in number; cells release their proximal end of the nail body secretions by exocytosis and empty them ○ Part of the nail matrix that is visible into hair follicles or onto the skin surface through pores Note! TWO MAIN TYPES OF SUDORIFEROUS The whitish appearance of the lunula/lunule is GLANDS due to the thick, opaque layer of keratinized cells The main types of sweat/sudoriferous glands in this region. are based on structure, location, and type of secretion Hyponychium ○ Eccrine sweat glands: “secreting ○ Thickened region of stratum corneum outwardly”; simple coiled tubular glands beneath the free edge Distributed throughout the skin, except ○ Secures the nail to the fingertip for the margins of lips, nail beds, glans Eponychium (cuticle) penis, labia minora, and eardrums. ○ Narrow band of epidermis that extends from Main function is for regulation of body and adheres to the margin (lateral border) temperature through evaporation. of the nail wall Apocrine sweat glands: also simple, coiled tubular glands BS PHARMACY ‘22 PHARM 120 10  SKIN DISORDERS/CONDITIONS Note! Skin diseases are conditions that affect the The cuticle protects the tissue inside your nail. skin. While this is usually removed during a manicure Rashes, inflammation, itching, and other skin for aesthetic reasons, its removal makes your abnormalities may result from these conditions. nails more prone to infection. Some skin diseases may be inherited, while others may be caused by lifestyle factors and aging Nail matrix ○ Epithelium deep to the nail root where the PSORIASIS cells divide by mitosis to produce growth ○ Where new nail is formed Chronic skin disorder in which keratinocytes divide and move more quickly than normal from the stratum basale to the stratum corneum. ○ As a result, the surface cells never get a chance to cycle into the later keratinizing stages. Common autoimmune disease that speeds up the life cycle of skin cells and often comes and goes. The extra skin calls that build up on the surface form scales and red patches that are itchy and sometimes painful. No cure, manage symptoms. ○ Effective treatments are various topical ointments and ultraviolet phototherapy. Suppress cell division, decrease rate of cell growth, or inhibit keratinization There are different types of psoriasis: Figure 12. Parts of the Nail in Dorsal View ○ Guttate psoriasis It is typically caused by bacterial infection such as strep throat. It is marked by small, drop-shaped, scalig spots. Figure 13. Parts of the Nail in Sagittal Section FUNCTIONS OF NAILS Figure 14. Guttate Psoriasis Help us grasp and manipulate small objects ○ Scalp psoriasis Protection against trauma to the ends of the causes raised, discolored plaques on digits the scalp or on the skin around the Scratching scalp. Indicator of one’s health status NAIL GROWTH Rate of nail growth varies on a person's age, health, and nutritional status. Can vary according to season, time of day, and environmental temperature Average growth in length of fingernails = about 1 mm in a week, slower in toenails The longer the digit, the faster the nail grows The nails grow more on the dominant hand. Figure 15. Scalp Psoriasis ○ Plaque psoriasis BS PHARMACY ‘22 PHARM 120 11  one of the most common types causes dry, itchy, raised skin patches or plaques. usually appears on the knees, elbows, and lower back. Figure 19. Pustular Psoriasis ○ Erythrodermic psoriasis least common the coverage is the whole body with a peeling rash. Figure 16. Plaque Psoriasis It can be short-term (acute) or long-term ○ Inverse psoriasis (chronic) common in overweight people affects the skin folds of the groin, buttocks, and breasts. gets more inflamed if greater sweat production Fungal infection may trigger this type of psoriasis. Figure 20. Erythrodermic Psoriasis PSORIATIC ARTHRITIS In addition to inflamed, scaly skin, psoriatic arthritis causes swollen, painful joints that are typical of arthritis Figure 17. Inverse Psoriasis Sometimes the joint symptoms are the first or ○ Nail psoriasis onlu manifestation of psoriasis or at times only can affect fingernails and toenails, nal changes are seen. causing pitting, abnormal nail growth, Symptoms range from mild to severe, and and discoloration. psoriatic arthritis can affect any joint Although the disease usually isn’t as crippling as other forms of arthritis, it can cause stiffness and progressive join damage that in the most serious cases may lead to permanent deformity. Figure 18. Nail Psoriasis ○ Pustular psoriasis Rare type of psoriasis clearly defined pus-filled blisters Figure 21. Psoriatic Arthritis ALBINISM Inherited inability of an individual to produce melanin BS PHARMACY ‘22 PHARM 120 12  Inability of melanocytes to synthesize tyrosinase Missing melanin in hair, eyes, and skin Figure 24. A person with severe acne Figure 22. A person with albinism VERNIX CASEOSA VITILIGO Newborn: skin is covered with vernix caseosa Partial or complete loss of melanocytes from Produced by the sebaceous glands patches of skin produces irregular white spots Protects the baby’s skin while it is floating in its May be related to an immune system water-filled sac malfunction in which antibodies attack the melanocytes Figure 25. A newborn with Vernix Caseosa MILIA Small, white/yellow bumps on the face Figure 23. Vitiligo on the hands Caused by the buildup of keratin Typically harmless and painless ACNE Appear as small white spots in the baby’s nose and forehead Occurs predominantly in sebaceous follicles May also appear in people of all ages, including that have been colonized by bacteria. adults ○ The infection may cause a cyst or sac of Resolves on its own, but may also be connective tissue cells to form, which can professionally removed via extraction or laser destroy and displace epidermal cells. treatment Usually begins at puberty, when the sebaceous glands grow in size & increase their production of sebum. If a sebaceous gland duct becomes blocked by sebum, a whitehead appears on the skin surface. If the accumulated material oxidizes and dries, it darkens, forming a blackhead. Figure 26. A baby with Milia SEBORRHEA Cradle’s cap Caused by overactivity of the sebaceous glands BS PHARMACY ‘22 PHARM 120 13  It begins on the scalps as pink, raised lesions SQUAMOUS CELL CARCINOMA that gradually form a yellow to brown crust that Arise from squamous cells of the epidermis sloughs off as oily dandruff Most arise from pre-existing lesions of Careful washing to remove the excessive oil damaged tissue on sun-exposed skin often helps. Figure 30. Squamous Cell Carcinoma MALIGNANT MELANOMA Figure 27. A baby with Seborrhea Arise from melanocytes Most prevalent life-threatening cancer in young MOLES women Nevus (sing.), Nevi (plural) Metastasize rapidly and can kill a person within Benign localized overgrowth of melanocytes months of diagnosis Produced by grouping of melanocytes that Accounts for about 2% of all skin cancers develop during the first years of life Figure 31. Malignant Melanoma Figure 28. Mole Table 3. Comparing moles vs. melanoma indications SKIN CANCER Excessive exposure to the sun Common forms: ○ Basal cell carcinoma ○ Squamous cell carcinoma ○ Malignant melanomas BASAL CELL CARCINOMA Tumors that arise from the cells in the stratum basale of the epidermis and rarely metastasize Accounts for about 78% of all skin cancers RINGWORM Also called tinea infections Caused by fungi Symptoms Figure 29. Basal Cell Carcinoma ○ itchy, patchy, scale-like lesions with raised edges BS PHARMACY ‘22 PHARM 120 14 Table 4. Ringworm infection and its location in the Transmitted by direct contact with an infected body individual Usually benign and disappears spontaneously Tinea Infections Location T. pedis Feet T. manuum Hands T. capitis Scalp T. corporis Trunk and face T. unguium Nails T. cruris Groin T. barbae Beard T. axillaries Armpit Figure 34. Different types of warts based on its structure COLD SORES Fever blisters Around the mouth & in the mucous membrane of the mouth Caused by Type I herpes simplex virus Initial infections show no symptoms Virus can remain dormant in the skin ○ Symptoms can show when immunocompromised Figure 32. Ringworm When activated, it produces small, fluid-filled blisters that can be both painful and irritating CELLULITIS Common bacterial skin infection that causes redness, swelling, and pain in the infected area of the skin Staphylococcus and Streptococcus spp. are the most common causes of cellulitis Wound care and hygiene are important for preventing cellulitis Figure 35. Cold sore SHINGLES Very painful, vesicular skin eruptions Caused by the herpes zoster or chickenpox virus that develop after the childhood infection Virus remain dormant within cranial or spinal Figure 33. Cellulitis nerve COMMON WARTS A.k.a. verruca vulgaris Caused by human papillomavirus Causes uncontrolled growth of epidermal tissue BS PHARMACY ‘22 PHARM 120 15  Macule small, up to 1cm (freckle) Patch larger than 1cm (vitiligo) Palpable elevated solid masses Papule Up to 0.5 cm Plaque a flat, elevated surface larger than 0.5 cm, often formed by the coalescence of papules Figure 36. Skin eruptions on chest Nodule 0.5 cm to 1-2 cm; often deeper and firmer than a papule IMPETIGO Highly contagious skin disease of children Tumor larger than 1 to 2 cm caused by the bacterium Staphylococcus Wheal a somewhat irregular, relatively transient, aureus superficial area of localized skin edema Bacteria are spread by direct contact & enter the skin through abrasions Circumscribed superficial elevations of the skin Skin erupts with small blisters containing pus formed by free fluid in a cavity within the skin that rupture easily, producing a honey-colored layers crust Blisters usually develop on the face & can Vesicle up to 0.5 cm; filled with serous fluid spread Bulla greater than 0.5 cm; filled with serous fluid Pustule filled with pus Note: Refer to summary table of trans for all photos BLISTER A vesicle or bulla Those of mechanical origin form from the friction caused by repeated rubbing on a single area of the skin May also develop from 1st- & 2nd-degree partial-thickness burns Figure 37. Ruptured blisters on child’s nose LESION Refers to a traumatic or pathologic loss of normal tissue continuity, structure, or function Sometimes refers to the components of a rash ○ Color Blanched - white Erythematous - reddened Hemorrhagic or purpuric - containing blood Pigmented ○ Cause Primary lesion - arises in previously normal skin Figure 38. Blister with pus on a finger Secondary lesion - results from other disease conditions Note! Table 5. Lesion Sizes Blisters contain serum which is an exudate of LESION SIZES extracellular fluid. Circumscribed, flat, nonpalpable changes in skin, All vesicles, like blisters, are supposedly sterile. change in color Meaning it is enclosed and no microbes are present. However when it gets infected, BS PHARMACY ‘22 PHARM 120 16  ○ Second-degree burn: lymphocytes will travel to the blister to kill Destroys the epidermis and part of the bacteria and pus will be formed as a by-product dermis of the activity of these lymphocytes. This then Some skin functions are lost becomes a pustule. Blisters can contain pus, especially since this is a common symptom ○ Third-degree burn: when we see that the color of the patient’s Full-thickness burn blisters turn yellow or colored instead of the clear Destroys the epidermis, dermis, and fluid which is the serum. subcutaneous tissue Most skin functions are lost Also, just like how microbes can enter the blister, it can be noted that small amounts of sweat and oil may also enter the blister. But if it primarily contains oil instead of serum, chances are it is not a vesicle but a cyst. On the other hand, if it contains sweat, healthcare professionals usually diagnose this as miliaria. However, in order to be sure or confirm the diagnosis, histopathology may be performed. CALLUS Abnormal thickening of the stratum corneum Figure 40. Comparison degrees of burns Produced by prolonged repeated rubbing or pressure PRESSURE ULCERS May be filed down but is likely to recur if the a.k.a. Decubitous ulcers or bedsores pressure continues Caused by a constant deficiency of blood flow to tissues CORNS Prolonged pressure causes tissue Abrasion on the bony prominences on the foot Small breaks in the epidermis become infected Small, well-circumscribed, conical keratinous The sensitive subcutaneous layer and deeper thickenings of the skin tissues are damaged, leading to tissue death Often accompanied with pain Occurs most often in bedridden patients May be surgically removed, but they recur if the With proper care, pressure ulcers are causative agent is not removed preventable Figure 41. Pressure ulcer on heel Figure 39. Comparison between callus and corn BURNS Tissue damage caused by excessive heat, electricity, radioactivity, or corrosive chemicals First and second degree burns are collectively called partial-thickness burns ○ First-degree burn: Involved only the epidermis Mild pain and erythema (redness) but no blisters (e.g. Mild sunburn) BS PHARMACY ‘22 PHARM 120 17  ○ Migratory phase ○ Proliferative phase ○ Maturation phase INFLAMMATORY PHASE Period when the inflammation happens Formation of blood clot Vasodilation of blood vessels to enhance the delivery of helpful cells such as neutrophils and monocytes Monocytes develop into macrophages to phagocytize microbes Figure 42. Stages of pressure ulcers Mesenchymal cells develop into fibroblasts for tissue formation SKIN WOUND HEALING As a layer designed for protection against MIGRATORY PHASE external environment, one of the methods for The blood clot turns into a scab the skin to regulate itself is via skin wound Epithelial cells migrate beneath the scab to healing bridge the wound Skin wound healing is divided into 2: Fibroblasts begin synthesizing scar tissue ○ Epidermal wound healing which is composed of collagen fibers and ○ Deep wound healing glycoproteins Damaged blood vessels start to regrow EPIDERMAL WOUND HEALING Occurs when the wound only reaches the PROLIFERATIVE PHASE epidermis such as light abrasions and minor Extensive growth of epithelial cells beneath the burns scab The first step in epidermal wound healing is for Deposition of collagen fibers in random the epidermal stem cells surrounding the patterns wound will break contact with the basement Continued growth of blood vessels membrane to enlarge and migrate across the wound MATURATION PHASE ○ As basal epidermal cells migrate, the Scab sloughs off hormone EGF stimulates the basal stem Collagen becomes more organized cells to divide and replace the ones that Decrease in fibroblasts moved into the wound Blood vessels are restored to normal ○ The relocated basal epidermal cells divide and thickens the new epidermis INTEGUMENTARY SYSTEM The second step is when the epidermal cells DEVELOPMENT encounter one another wherein they stop The epidermis starts to be developed from the migrating due to contact inhibition ectoderm which covers the surface of the The final step is the halting of migration when embryo epidermal cells are in contact with other During the 4th week after fertilization, the epidermal cells on all sides epidermis consists of a single layer of ectodermal cells (basal layer) DEEP WOUND HEALING During the 7th week, the basal layer divides Happens when the wound extends to the and forms the periderm which is sloughed off dermis and subcutaneous tissue and becomes a component of vernix caseosa Scar tissue is formed and the healted tissue during the fifth month of development loses some of its normal function ○ The vernix caseosa covers and protects the Fibrosis is the medical term for the process of skin of the fetus from the constant exposure scar tissue to the amniotic fluid in which it is bathed A scar could either be hypertrophic or ○ Also facilitates the birth of the fetus keloid/cheloid: because of its slippery nature and protects ○ Hypertrophic scars remain within the the skin from being damaged by the nails boundaries of the original wound During the 10th week, a thick epithelial layer ○ Keloid/cheloid scars extends beyond the (primary nail field) are developed into nails boundaries of the original wound which will reach the fingertips during the ninth Deep wound healing occurs in four phases month (developed distally) ○ Inflammatory phase BS PHARMACY ‘22 PHARM 120 18  During the 11th week, numerous integumentary Facelift, browlift, or necklift, pertains to an system occurs invasive surgery in which loose skin and fat are ○ The basal layer form an intermediate layer removed surgically and the underlying of cells connective tissue and muscle are tightened ○ Basal cells eventually form all epidermal layers, epidermal ridges, and dermal papillae ○ Cells from ectoderm differentiate into melanoblasts which will become melanocytes ○ Mesenchymal cells (from the mesoderm developed from the ectoderm) differentiate into fibroblasts During the 12th week, hair follicles develop ○ Hair downgrowths known as hairbuds also develop where distal ends become club-shaped, forming the hair bulbs During the late days of the first trimester, dendritic cells arise from the red bone marrow and invade the epidermis On the 4th month, most sebaceous glands develop On the 5th month, hair follicles produce lanugo During the 4th to 6th months, tactile epithelial cells appear in the epidermis with its origin currently unknown SKIN ANTI-AGING PROCEDURES Topical products that bleach the skin to tone down blotches and blemishes (hydroquinone) or decrease fine wrinkles and roughness (retinoic acid) Microdermabrasion which is the use of tiny crytalls under pressure to remove and vacuum the skin’s surface cells to improve skin texture and reduce blemishes Chemical peel referring to application of mild acid to the skin to remove surface cells and to improve skin texture while also reducing blemishes Laser resurfacing pertains to the use of a laser to clear up blood vessels near the skin surface and decrease fine wrinkles Dermal fillers which are injections of human collagen, hyaluronic acid, hydroxylapatite, or poly-L-lactic acid that plumps up the skin to smooth out wrinkles and fill in furrows, such as those around the nose and mouth and betwee the eyebrows Fat transplantation in which fat from one part of the body is injected into another location such as around the eyes Botulinum toxin or Botox that is a diluted version of a toxin that is injected into the skin to paralyze skeletal muscles that cause the skin to wrinkle Radio frequency nonsurgical facelift refers to the use of radio frequency emissions to tighten the deeper layers of the skin of the jowls, neck, and sagging eyebrows and eyelids BS PHARMACY ‘22 PHARM 120 19