1 / 12

Plate 49

Plate 49. Establishment of Disease. Skin. Epithelium – outer part of skin Epi : “on” Theli: “tissue” Densely packed cells protect body from invading pathogens. Skin. Connective tissue – provides cohesion and support to internal structure of the body Fibers provide flexibility and form.

magda
Download Presentation

Plate 49

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Plate 49 Establishment of Disease

  2. Skin • Epithelium – outer part of skin • Epi: “on” • Theli: “tissue” • Densely packed cells protect body from invading pathogens

  3. Skin • Connective tissue – provides cohesion and support to internal structure of the body • Fibers provide flexibility and form

  4. How do bacteria get into your skin?

  5. Phagocytes • After a foreign substance has ruptured the skin, phagocyte cells migrate to the site • Phagein: “to eat” • Cyte: “cell” • Phagocytes – group of immune cells specialized in “eating” potential pathogens • Pus from an infection is primarily dead phagocytes

  6. Phagocytosis • http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__phagocytosis.html

  7. Bacterial Enzymes • Bacteria use enzymes to help establish themselves in the body: • Coagulase • Hyaluronidase • Streptokinase • Hemolysis

  8. Coagulase • Coagulase is secreted by some bacteria (ex: Staphylococcus) • Causes proteins in blood to clot • Commonly found in Gram positive bacteria • Blood clot surrounds bacteria and protects against phagocytes

  9. Hyaluronidase • Hyaluronic acid (hyaluronan) is found in epithelial and connective tissues and acts as a “goo” in tissue repair • Bacteria (ex: Clostridium) secrete hyaluronidase enzyme to breakdown hyaluronic acid • It allows bacteria to infiltrate skin barrier • Fun fact: sperm secrete hyaluronidase when they come into contact with an egg

  10. Streptokinase • Some bacteria (ex: Streptococcus) secrete streptokinase enzyme to dissolve blood clots • Allows bacteria to spread past the location of initial infection • Also used in heart attack victims to dissolve arterial blood clots in the heart

  11. Hemolysin • Some bacteria secrete hemolysin that breakdown cell membranes of red blood cells • Lowers oxygen levels in blood, improving conditions for anaerobic bacteria (ex: Clostridium) • Lowers activity of white blood cells and protects bacteria • Can result in anemia (low levels of RBC)

More Related