healing Flashcards
7
what initiates healing
tissue damage (any type)
what is the main goal of repairing damaged tissue?
return the tissue to its normal anatomy and normal function
during tissue repair what cells are proliferated?
fibroblasts
endothelial cells
roll of fibrous tissue
gives substance and strength to healing tissue
what are fibroblasts
specialized cells that can produce fibrous tissue (which gives substance and strength to healing tissue)
healing by the first intention
- takes place after an injury in which there has been minimal tissue damage and ideally no bacterial contamination (eg, surgical incision)
- good tissue apposition, no tissue loss
- endothelial cells increase in size and number, forming capillary loops
- the capillary loops join across the injured area and form functioning blood vessels
- fibroblasts begin laying down fibrous tissue
- the repair will resemble new tissue in 2-3 weeks with minimal scaring
healing by secondary intention
- in tissues with considerable tissue loss and damage
- initially, a blood clot temporarily fills the tissue loss, protecting the region
- endothelial cells and fibroblasts grow into the space, producing much more fibrous tissue than healing by first intention
- the capillary loops are extensive and give the healing tissue a granular appearance
- the epithelium grown under the clot.
- eventually, the clot falls off (scab) the damaged area, leaving the epithelium to protect the repaired tissue
- more scaring
what is vaccination
a procedure that helps the immune system to become even more effective in fighting off invaders
are allergies an immune system malfunction?
yes
most common
variolation
- precursor to vx
- from ancient Chinese practices
- rubbing the puss of an individual with smallpox into the scratch wounds of a healthy individual
- most individuals recovered but some died so the practice became unfavoured
cross-protection
when the antibodies made for one virus (cowpox) can protect against a different virus (smallpox)
developed by Edward Jenner
immunology
the study of the defense mechanism of the body
antibodies
proteins produced by the body in response to a foreign substance that protects the animal from disease
how can we develop immunity to a disease?
- from having the disease and recovering
- vaccination
both are due to the production of antibodies
treatment for viruses
Generally no treatment
What is the most important method of disease control for all animals in the world?
vx
species/natural resistance
- some sp never get some diseases
- characterized by a complete resistance by all members of the species
- mechanisms of resistance not fully understood but we know it is not dependent on specific antibodies
- natural immunity occurs without medical (human) intervention
artificial immunity
medically induced immunity
innate immune system
- non-specific immunity (immunity we are born with)
- includes physical and chemical barriers (intact skin, stomach acid, commensal organisms, mucus production, cilia, lysozyme in tears, body temperature)
- involves humoral and cell-mediated systems
- include inflammatory responses (particularly phagocytes)
- eg, wound healing
if the innate immune system is successful, the adaptive immune response will not be activated and antibody production will not occur - occurs immediately after antigen entry
- no specificity
what is the body’s first line of defense?
phagocytes
when does innate immunity begin?
Immediately after an antigen enters
how long does antigen production take?
a few days
why is it good/important that the innate immune system takes place immediately?
because antibody production takes a few days