Host Response: Study Guide

Question 1

what is the sequence of hose reactions following implantation of medical devices?

Answer 1

Injury 
• Blood-material interactions 
• Provisional matrix formation
 • Acute inflammation
 • Chronic inflammation
 • Granulation tissue 
• Foreign-body reaction 
• Fibrous capsule development

Question 2

what is resolution?

Answer 2

when presence of implant prevents attainment of original condition but a steady state in attained. this state is called resolution

Question 3

what is the objective of blood clotting?

Answer 3

to form a patch that isolates the leak and stops blood loss

Question 4

what is the difference between immunity and allergy

Answer 4

immunity- is the property of being secure or nonsusceptible to the adverse effects of foreign agents

allergy- is the property of being especially senstive (or hypersensitive) to foreign agents

Question 5

when is blood coagulation good

Answer 5

??? when they slow/halt blood flow to prevent to much blood loss

Question 6

name 3 cells that actively take part in the sequence of local events following implatations

Answer 6

polymorphonuclear leukocytes-acute inflamation

monocytes (macrophage and lymphocytes—- chronic inflamation

fibroblast—- new blood capilaries

Question 7

what are granulocytes

Answer 7

any blood cell containing specific granules (e.g. neutrophils, eosinophils, basophils)

Question 8

give two characteristics of platelets

Answer 8

• little plates, non nucleated- disc-shape cell
• produced in bone marrow
• circulate in blood
• lifespan: 10 days

Question 9

what is a leukocyte?

Answer 9

: a colorless (white) blood cell capable of ameboid movement (e.g. lymphocytes, monocytes, granulocytes)

Question 10

firbrinolytic system removes unwanted ____deposits to improve blood flow and facilitate healing process

Answer 10

fibrin

Question 11

___ is the first in the sequence of host reaction following implantation of medical devices

Answer 11

injury

Question 12

what is the body’s response to damaged blood vessels?

Answer 12

blood clotting

Question 13

what are platelets? state two functions of ‘platelets’ as its relates to the process of blood coagulation

Answer 13

are non nucleated disc–shaped cells that are produced in the bone marrow.. they circulate throughout the blood and have a lifespan of 10 days

functions-

• arrest bleeding through formation of platelet plugs
• stabilize platelet plugs by coagulation reactions, leading to formation of fibrin

Question 14

what is tumorigensis

Answer 14

the production or development of tumors

Question 15

what is the sequence of host reactions after implantation of medical devices?

Answer 15

• Injury
• Blood-material interactions
• Provisional matrix formation
• Acute inflammation
• Chronic inflammation
• Granulation tissue
• Foreign-body reaction
• Fibrous capsule development

Question 16

differentiate between cell mediated and humoral immune response mechanisms

Answer 16

– humoral (humor=fluid)
• soluble antibodies freely circulating

– cell-mediated
• antibodies attached on the cell walls

Question 17

state two drawbacks of antibiotic impregnated implants

Answer 17

–appropriate antibiotic:=
late infection is produced by a range of bacteria

–antibiotic sensitivity=the removal of the implant

–antibiotic penetration= may not be efficient

–chronic use =
of antibiotics leads to more resistant virulent strains

Question 18

describe two causes for implanted device related infection

Answer 18

S. Epidermis (human skin bacteria)- primary cause of infection of implanted polymeric biomaterials….. artifical heart joints, total joints, catheter

S. aureus.- is a major pathogen isolated from metallic-related and soft tissue infenctions

P.aeruginosa- is the primary pathogen of specal sites such as….. contact lenses, total artificial hearts

Question 19

differentiate between benign and malignant tumors

Answer 19

Benign- do not pentrate adjacent tissue, nor do they metastasized( spread to distant sites)

malignant- tend to invade adjacent tissues, metastasize via blood and lymph vessels