Micro W12 Flashcards
Innate defences
Always active; 1st and 2nd lines of defence
Acquired (adaptive defences)
Must be stimulated to become active; 3rd line of defense
Innate host defense barriers include
Physical
Mechanical
Cellular
Antimicrobial chemicals
Examples of physical barriers
Unbroken skin
Mucous membranes (eyes, nose, mouth)
Mechanical barriers examples
Movement of cilia
Sticky nature of mucous
Hair in the nose
Coughing, sneezing, shedding of skin cells
Examples of antimicrobial chemicals
HCL in stomach
Organic acids on skin
Interferon
Cellular barrier examples
Phagocytes (neutrophils/macrophages)
Is acquired immunity present at birth
No
Antigens are foreign to the ____ and activate the ____
The body
Immune response
In acquired immunity the immune system learns how to attack
Antigens and develops memory
Lysosome (chemical barrier) is an enzyme produced in
Sweat
Tears
Saliva
(Kills bacteria)
Gastric juices (chemical barrier) is
Stomach acids that kills bacteria and toxins
Saliva (chemical barrier) dilutes
MO’s and washes oral cavity
Phagocytosis
Phagocytes destroy microbes in body tissues
Localized response to damage is called
Inflammation
Response to infection that inhibits bacterial growth and increases rate of repair
Fever
T-lymphocytes (acquired immunity) is a ___ mediated response
Cell mediated response
(Helper T cells and killer T cells)
B-lymphocytes (acquired immunity) is a ____ mediated response
Antibody mediated response
(Memory cells)
Plasma produces
Antibodies
5 main types of white blood cells
Lymphocytes
Monocytes
Neutrophils
Eosinophils
Basophils
White blood cells (aka leukocytes) protect against
Infectious disease and foreign invaders
These are more common in lymph than in blood, they have the longest lifespan (memory cells) and include B cells and T cells
Lymphocytes
B cells attack ____ and where?
Attack invaders OUTSIDE the cells
T cells attack
Infected cells
B cells divide to produce
Plasma and memory cells
Produces antibodies which bind to antigens and eliminate them
Plasma
Effectively respond to a second encounter with a pathogen
Memory cells
Activate more WBC’s and are driving force in maintaining defense system
Helper T cells
Killer/ cytotoxic cells
Track down cells infected with virus
Largest wbc?
Monocytes
Monocytes turn into what when they leave the bloodstream
Macrophages
Most abundant wbc?
Neutrophils
Neutrophils (aka PMNs) are the first responders to what kind of infections?
They make what
Bacterial and fungal infections
Make pus
Found mostly in mucous membranes and deal with parasitic infections and allergic reactions
Eosinophils
Rarest of the wbc
Basophils
Basophils are responsible for what response and release what
Allergic and antigen response
Release histamine
Process of inflammation
- Blood supply to site is increased
- Capillary permeability is increased (neutrophils ¯ophages are present)
- WBC migrate from the capillaries into the affected tissues
To the site of inflammation the earliest cells to arrive are____ followed by
Earliest = neutrophils
Followed by monocytes/macrophages, and lymphocytes
Artificial immunity involves being
Immunized or vaccinated against a specific disease
Activation of the immune system by certain antigens can cause damage to the body; what is an example of this
Pollens- antibody-mediated allergic reaction to the nose and eyes
HAY FEVER
ASTHMA
Allergy to a substance distributed throughout the body may result in a widespread reaction affecting blood stream, lungs, and heart
Anaphylactic shock
Cell mediated allergic reaction
(Ex nickel, poison ivy, latex gloves)
Contact dermatitis
The initial immune response = increased number of
Lymphocytes
Once we had an infectious disease we frequently
Will NOT get that disease again
In phagocytosis the cell membrane will surround a bacteria to produce a pocket that will eventually close tightly around the bacteria; this pockets is a
Vacuole called the phagosome
Lysosomes will merge with the membrane of the phagosomes to produce a combined vacuole called the
Phagolysosome
The lysosomal enzymes in the vacuole digest the
Bacterial cell
Most of the time macrophages and neutrophils function as low level
Garbage collectors
Sharps is a term for
Devices with sharp points or edges that can puncture or cut skin/other tissue
Examples of sharps in dental
Injection needle
Ortho bands/wire
Scalpel blades
Burs
Suture needles
The most serious types of occupational exposure to blood borne pathogens are accidental
Percutaneous (through the skin) injuries involving sharps
Sharp injuries are primarily associated with potential for occupational transmission of
Hep B (HBV)
Hep C (HCV)
Human immunodeficiency virus (HIV)
Sharp injuries can occur at anytime when handling a sharp item, examples
At chairside
During instrument processing
At other times
Establishing a _____ in the office is one overall strategy suggested by CDC to prevent sharp injury
Safety culture
3 basic approaches to prevent sharp injuries
- Eliminate or limit use of sharps when possible
- Apply engineering controls (sharps container)
- Apply workplace controls (ex. One handed scoop)
An exposure management protocol must be included in the ipac manual and must include the following
First aid procedures
Treatment
Documentation
Record the date/case number/status of person
