Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
99 Cards in this Set
- Front
- Back
|
Epidermis General Features
|
stratified squamous
made up mainly of Keratinocytes 5 zones |
|
|
Epidermis:
Stratum Basale |
single layer of Keratinocytes
basal lamina underneath, connected by Hemidesmosomes have many Keratin IF within |
|
|
What connect Stratum Basale to the Dermis?
|
Hemidesmosomes
|
|
|
What stimulates Keratinoctye production?
|
Epidermal Growth Factor (EGF)
Interluekin 1a |
|
|
What inhibits Keratinocytes production?
|
Transforming Growth Factor (TGF)
|
|
|
Epidermis:
Stratum Spinosum |
Keratin IF in Tonofibrils
contain Membrane Coating Granules (MCG) Helps to waterproof skin |
|
|
What are Tonofibrils and where are they found?
|
buncles of Keratin IF in Stratum Spinosum
give cells a spiny look |
|
|
Epidermis:
Stratum Granulosum |
1-5 layers of flattened Basophilic Keratinoctyes
Contain Keratohyaline Granules help to waterproof |
|
|
What are in Keratohyaline Granules?
|
Filaggrin, which is an aggregator of Keratin IF
|
|
|
Epidermis:
Stratum Lucidum |
4-6 layers
thin cells, usually white |
|
|
Epidermis:
Stratum Corneum |
layers of fat and Keratinized Cells
outer cells are lifeless shells of Keratin IF transport from base to surface is 20-30 |
|
|
What does Filaggrin do to Stratum Corneum cells?
|
binds IF into bundles
|
|
|
Langerhans Cells
|
Dendritic cells in epidermis
irregular nucleus, washed out Cyto contain Birbeck Granules Participate in immune defense |
|
|
What immune reaction do Langerhans cells participate in?
|
delayed hypersensitivity reaction
present antigens to T-Lymphocytes |
|
|
What are Langerhans Cell origins?
|
bone marrow stem cells
|
|
|
What do Langerhans cells express?
|
MCH 1 and 2
CD1a |
|
|
Birbeck Granules
|
racket shaped
contain Langerin and CD1a used in uptake and delivery of antigens |
|
|
Merkel Cells
|
Neuroendocrine cells
Found in Stratum Basal allow perception of temp., pressure, and noxious substances free nerve endings present |
|
|
Merkel Cell Granules
|
contain neuropeptides (VIP, ACTH, Somatostatin, Calcitonin)
|
|
|
Merkel Cell Origin
|
Cells of the Stratum Basal in Epidermis
dependent on TF Atoh1 |
|
|
Melanocyte
|
produces Melanin
Melanosome granules contain melanin |
|
|
Where are Melanosomes found?
|
Melanocytes and Keratinocytes
|
|
|
What enzyme is required for Melanin production in Melanosomes?
|
Tyrosinase
|
|
|
Why is skin color different?
|
SAME number of Melanocytes
different amount of Melanin produced and retained |
|
|
How are Melanocytes attached to surrounding cells?
|
NOT bound to adjacent Keratinocytes by Desmosomes
bound to Basal Lamina by Hemidesmosomes |
|
|
Dermis Features
|
Dense, irregular CT
Dermal Papilla project up into epidermis to form primary ridges 2 layers: papillary and reticular |
|
|
Blister Formation Causes
|
Extracellular Desmosomes Destroyed
Defects in Keratin in Basal Layer Defect in Laminin Defect in Type VII collagen |
|
|
Arrector Pili Muscles
|
SM in slender bundles that insert into body of hair follicles
|
|
|
Sebaceous Glands
|
located about insertion of Arrector Pili into hair follicle
ducts open into hair follicle Some open directly to skin surface |
|
|
What do Sebaceous Glands secrete?
|
secrete a thick substance w/ fat droplets
|
|
|
Where do Sebaceous Glands NOT occur?
|
palms, soles, sides of feet
|
|
|
Eccrine Sweat Glands
|
found in deep dermis or hypodermis
opens to skin through sweat pore secretory organ for Urea, NH3, K+ and Uric Acid |
|
|
Innervation of Eccrine Sweat Glands
|
cholinergic sympathetic/thermoregulatory
sometimes adrenergic sympathetic |
|
|
Apocrine Sweat Glands
|
found in axillary, areolar and anal regions
located in deep dermis and ducts open into canal of hair follicle |
|
|
When do Apocrine Sweat Glands become active?
|
note until puberty
|
|
|
Apocrine Sweat Gland secretions?
|
contain protein, carbohydrate and others
secretion is viscous and odorless but BO can come from bacteria of secretion |
|
|
Specialized Apocrine Sweat Glands
|
Glands of Moll
found in eyelids, auditory canal |
|
|
Innervation of Apocrine Sweat Glands?
|
Adrenergic nerves
|
|
|
Nerves in the Skin
|
Efferent Nerves that activate glands and control blood
Sensory Nerves: Free endings and Encapsulated Nerve Endings |
|
|
Sensory Nerves of the Skin:
Free Endings |
pain or thermoreceptors
may induce secretory response in Merkels |
|
|
Sensory Nerves of the Skin:
Encapsulated Nerve Endings |
Pacinian Corpuscles-pressure
Meissners Corpuscles- tactile sensation |
|
|
Fxn of Skin:
Protection |
Keratin IF and Matrix provide protection
|
|
|
Fxn of Skin:
Synthesis of Vitamin D |
7 dehydrocholesterol transformed to Vitamin D
|
|
|
Fxn of Skin:
Permeability Layer |
lipid layers in skin are resistant to bacterial attack and oxidation
|
|
|
Fxn of Skin:
Thermoregulation |
sweating controlled by Hypo through sympathetic fibers
|
|
|
Fxn of Skin:
Immunological |
Keratinocytes promote maturation of T-Lymphocytes
Langerhans present antigens (is bound by AIDS) |
|
|
Sickle Cell Disease
|
Mutation leading to precipitation of Hbg, subject to hypoxia and this causes a sickle-shape instead of the biconcave disk
more rigid and more fragile |
|
|
Hereditary Spherocytosis
|
production of RBC’s that are sphere-shaped
more susceptible to hemolysis mutation in ankyrin is the most common defect can cause Spleen to enlarge |
|
|
Leukemoid Reaction
|
Persistent neutrophilia due to a redistribution of neutrophils
Redistributed from the marrow, microcirculation, and marginating compartment Causes: inflammation, infection and malignancy |
|
|
Chronic Granulocytic Leukemia
|
Proliferating cells are partly or completely differentiated
Myelocytes, metamyelocytes, band forms and neutrophils appear in the peripheral blood Total WBC count is >100k/ul (could be up to 300k) |
|
|
Charcot Leyden Crystals
|
Phospholipase B crystals that are found in diseases associated with eosinophilia and are seen in the secretions or excretions (sputum, feces) or CT
|
|
|
Cellularity of the Bone Marrow
|
Hypercellular marrow is characteristic of bone marrow affected by tumors of hematopoietic cells
|
|
|
Thrombocytopenia (TCP)
|
TCP is a platelet count <150,000/ul, could be due to decreased production or increased destruction
alcohol which impairs the maturation of megakaryocytes Counts rise after 3-5 days |
|
|
Chronic Granulomatous Disease
|
deficient NADPH oxidase in the cell membranes of PMN’s and monocytes
reduced production of O2 means the respiratory burst (RBP) is absent OHCl is not synthesized because of the absence of H2O2 and thus some bacteria are not killed |
|
|
Monocytosis
|
Greater than 10% of total WBC count or grater than 800/ul
Cause: bacterial, viral and protozoan infections. Chronic infections (TB), Autoimmune Disease (RA) |
|
|
Acquired Immunodeficiency Disease
|
Mediated by RNA retrovirus called human immunodeficiency virus (HIV)
HIV utilizes a glycoprotein (gp120) on its surface to bind to CD4 protein on the surface of T helper cells allows the virus to fuse with CD4+ T cells |
|
|
Where does HIV replicate?
|
inside T Cells
|
|
|
What does HIV Cause?
|
decreased number of CD4+ T helper cells so the patient gets recurrent infections by opportunistic pathogen
|
|
|
how does Immune System respond to HIV infection?
|
generating CD8+ T cytolytic cells and Abs
|
|
|
How do u treat HIV?
|
cocktail of chemotheraputic agents including AZT- an inhibitor of reverse transcriptase
|
|
|
Lymphedema: Primary
|
Abnormal swelling of arm/leg
rare, inherited disorder causing improper development of lymphatic vessels |
|
|
Lymphedema: Secondary
|
caused by surgery (removal of LN/vessels- breast cancer), radiation tx for cancer (scarring of LN/vessels), obstruction by a mass or infection
|
|
|
Lymphangiomas
|
Benign tumors of lymphatic vessels
due to incomplete development and obstruction obstruction of lymph flow which leads to the formation of cysts |
|
|
Cystic Hygromas
|
Symmetrical accumulation of fluid around the neck and head
chromosomal abnormalities (Turners, Trisomys 21, 18, and 13) leads to cardiac failure |
|
|
Tonsilitis
|
Inflammation of tonsils causing sore throat and fever
Tx: antibiotics |
|
|
Enlarged Lymph Nodes
|
Infection causes the activation & migration of B cells to nodules in the cortex of lymph nodes
Activated B cells proliferate rapidly leading to increased node size |
|
|
Autoimmune Disease
|
Malfunction of immune system so that it can no longer tell self from non-self
Lymphocytes see Ags derived from self as foreign, causing destruction of healthy tissue Tx: generally consists of immunosuppressive drugs |
|
|
DiGeorge Syndrome (congenital thymic aplasia)
|
deletion of 22q11 (30 genes)
Congenital absence of thymus and parathyroid glands caused by abnormal development of 3rd and 4th pharyngeal pouches |
|
|
What does Immune Systems does DiGeorge Syndrome cause?
|
Associated with abnormal cell-mediated immunity but normal humoral immunity
|
|
|
Can DiGeorge Syndrome be cured?
|
Tx: Bone marrow transplant (thymus)
|
|
|
Hodgkin’s Lymphoma
|
Malignant growth of lymph system cells
painless enlargement of lymph nodes, splenomegaly, heptamegaly Tx: chemotherapy, bone marrow/ peripheral blood transplants, immunotherapy (mAbs) &/or radiation therapy |
|
|
Diabetes Insipidus
|
Absence or decreased prod of ADH caused by a lesion of the hypothalamus or post. Lobe of the pituitary gland
Absence or decreased ADH will cause the production of large volumes or dilute urine Tx: Synthetic ADH |
|
|
Pituitary Adenoma
|
Tumors of the Anterior Pituitary usually composed of secretory cells
Enlarge and often suppress secretions by the remaining pars distalis cells Tx: surgical removal |
|
|
Thyroid Hormones Essential in Fetal Development
|
T3 and T4 cross the placental barrier; CRITICAL in early stages of brain development
T3 and T4 also stimulate gene expression for GH in somatotrophs |
|
|
Graves Disease
|
Diffuse enlargement of thyroid gland and protrusion of the eyeballs
binding of autoimmune IgG Abs to TSH receptors which stim the thyroid follicular cells to increase thyroid hormone secretion |
|
|
Prescription of Graves Disease?
|
Tx: surgical removal of the thyroid gland or radiotherapy (labeled iodine) to destroy most of the active follicular cells and immunosuppression
|
|
|
Simple Goiter
|
Most common symptom of thyroid disease
Enlargement of thyroid gland due to excessive release of TSH Due to insufficient iodine in the diet Tx: increased iodine in diet or synthetic thyroid supplement |
|
|
Hyperparathyroidism
|
Over-activity of parathyroid glands leading to excess secretion of PTH and subsequent bone resorption
Associated with high blood Ca Tx: in minor cases, decrease the amount of intake of Ca rich foods. In severe cases is partial removal of the gland by surgery |
|
|
Diabetes Mellitus
|
Decrease in or total absence of plasma insulin which causes increased blood glucose levels
|
|
|
Diabetes Mellitus: Type 1
|
Insulin dependent; juvenile onset
Distinguished by damage to and destruction of B cells of the iselts Tx: Combination of diet and insulin therapy |
|
|
Diabetes Mellitus: Type 2
|
Non insulin dependent
DOES NOT result from low levels of insulin in the blood Is INSULIN-RESISTANT (decreased binding of insulin) Usually controlled by diet |
|
|
Addison Disease
|
Characterized by secretion of inadequate amounts of adrenocortical hormones
destruction of the adrenal cortex S/S= weight loss, muscle weakness, fatigue, low BP, and skin hyperpigmentation |
|
|
Multiple Endocrine Neoplasia (MEN)
|
Defined as pts who have two or more tumors of endocrine glands
|
|
|
Multiple Endocrine Neoplasia (MEN):
MEN 1 |
Prevalence 1:35,000 associated with pituitary adenoma, parathyroid hyperplasia, and pancreatic tumors
|
|
|
Multiple Endocrine Neoplasia (MEN):
MEN 2 |
Parathyroid hyperplasia, medullary pheochromocytoma and thyroid carcinoma
|
|
|
Pemphigus Vulgaris (PV)
|
A chronic , blistering skin disorder caused by the action of IgG abs to surface ags on keratinocytes
Autoimmune disorder |
|
|
What type of Immune Reaction is Pemphigus Vulgaris (PV)?
|
Type II hypersensitivity reaction
|
|
|
Epidermolysis Bullosa (EB)
|
1)Epidermolytic= defects in keratin within the basal layer- keratin molecular defect
2) Junctional= cleavage in the lamina lucida, defect in laminin 3) Dermolytic= entire basal lamina and epidermis split- defect in type VII Collagen (anchoring fibrils) |
|
|
Sweating and Disease
|
ex: Cystic Fibrosis
Sweat test, an indicator of CF, will show elevated sodium and chloride levels |
|
|
Skin Repair
|
repair of a laceration or incision requires stimulated growth of both the dermis and epidermis
|
|
|
Skin Repair: Dermal Repair
|
1) removal of the damaged collagen fibers in the wound (via macros) 2)proliferation of fibroblasts and subsequent prod of new collagen
|
|
|
Skin Repair: Epidermis Repair
|
proliferation of the basal keratinocytes in the St. Germ (S.G.) in the undamaged area around the wound
|
|
|
Will skin always heal itself?
|
massive destruction from 3rd degree burns prevent reepithelialization
require skin graft |
|
|
Steps of Skin Healing?
|
1- clot forms
2- platelets release factors 3-neutrophils and macrophage appear 4-KGF's released 5-MMP's released by K's 6-MMPs cut Type IV and VII collagen to release Keratinocytes 7-MMPs cut collagen 1 and 2 8-Reepithelialization occurs |
|
|
Scleroderma
|
Excessive production of collagen in the dermis
Type I and Type II collagen are extensively deposited in the papillary layer and then eventually the reticular layer T cells accumulate at some point, secrete cytokines and this results in increased collagen synthesis |
|
|
Albinism
|
tyrosinase positive albinism: tyrosinase is present but is unable to enter melanocytes to produce melanin
tyrosinase negative: this enzyme is not produced |
|
|
Psoriasis
|
noncontiguous skin disorder that most commonly appears as inflamed w/ silvery white scale
Cells reach apical layers in a short time (2-3 days) associated with an increase activity of T cells (autoimmune) |
|
|
Griscelli Syndrome
|
Associated with partial albinism of the hair and skin, results from mutation in myosin Va gene
motor protein that binds to actin and the melanosome when it is released from the microtubule in dendrite |
|
|
Acne Vulgaris
|
plugging of the outlet of a hair follicle by keratin
Bacteria are involved causing inflammation Tx: antibiotics and topical steroids |
