Biomedical Flashcards
(181 cards)
1
Q
what is inflammation
A
response of vascularized tissues to infection and damage that brings cells and molecules of hose defense from the circulation to cites where they are needed in order to eliminate offending agents
2
Q
what 3 main things does inflammation do
A
- rid the host of the initial cause of injury
- remove necrotic cells and tissues
- initiate the process of tissue repair
3
Q
what are the cardinal signs of inflammation (medical language)
A
rubor, calor,tumor, dolor, functio laesa
4
Q
what are the cardinal signs of inflammation (normal words)
A
redness, heat, swelling, pain, loss of function
5
Q
what cells in the blood participate in inflammation
A
platelets & leukocytes (neutrophils, monocytes, lymphocytes)
6
Q
what cells in the tissue participate in inflammation
A
sentinel cells
7
Q
what are sentinel cells
A
immune cells that reside in tissues
8
Q
what are the 3 key features of sentinel cells
A
- surface/cytosolic receptors invading microbes/ substances released by necrotic tissues
- binging, ingesting and phagocytize microbes and necrotic tissues
- release cytokines and other inflammatory mediators
9
Q
what are cytokines
A
signaling molecules secreted by immune cells in response to injury/infection that induce and modulate the immune response (both pro and anti inflammatory)
10
Q
what are examples of cytokines
A
interleukins, interferon, TGT-beta, TNF
11
Q
what is the job of pro-inflammatory cytokines
A
induce fever, inflammation & tissue destruction in response to injury
12
Q
what is the job of anti-inflammatory cytokines
A
suppress actions of pro-inflammatory
13
Q
what is histamine
A
molecule released by mast cells that cause vasodilation and increase capillary permeability
14
Q
what is produced in response to cytokines
A
prostoglandins and leukotrienes
15
Q
what is the job of prostaglandins and leukotrienes
A
contribute to vasodilation, pain, platelet activation
16
Q
what is hemostasis
A
immediate response to traumatic injury to prevent blood loss
17
Q
what is caused by the mediators released by endothelial cells during hemostasis
A
vasoconstriction, platelet activation, fibrin clot formation
18
Q
what occur during platelet formation
A
- platelets adhere to lesion/each other
- cause attraction of other platelets
- initiate coagulation cascade leading to fibrin production
19
Q
what are the five steps of the inflammatory process
A
- recognition of injury
- recruitment of white blood cells to area of injury
- removal of injurious agent/damaged tissue
- regulation of response
- resolution
20
Q
how is injury recognized
A
sentinel cells in tissue and leukocytes in blood stream
21
Q
what are the primary roles of recognition in the inflammatory process
A
ingestion and phagocytosis of microbes and necrotic tissues, cause the release of mediators that trigger recruitment
22
Q
what mediators trigger recruitment
A
cytokines, histamines, prostaglandins, bradykinins, leukotrienes
23
Q
how are cells recruited?
A
cytokines and inflammatory mediators act on endothelial cells of local blood vessels causing vasodilation, increased vessel permeability and vascular stasis
24
Q
describe vasodilation during recruitment
A
triggered by histamine and other mediators released by mast cells; results in increased blood flow accompanied by decreased velocity of flow
25
describe vessel permeability in recruitment
permeability increased due to endothelial cell retraction; allows for plasma and proteins to lean into tissue causing edema
26
describe vascular stasis in recruitment
results from increased blood flow and decreased velocity and hemoconcentraion; accounts for redness and warmth of inflamed tissue, facilitates extravasation of leukocytes into tissues
27
how are leukocytes recruited into tissues
activation, extravasation and chemotaxis
28
describe activation of leukocyte recruitment
cytokines produced by mast cells and activated by platelets "turn on" leukocytes
29
describe extravasation of leukocyte recruitment
vascular endothelial cells express surface proteins that "grab" leukocytes causing tehm to roll, adhere and migrate through the endothelium into tissue
30
describe chemotaxis of leukocyte recruitment
once in the tissue, leukocytes migrate to area of damage
31
how is damaged tissue removed?
1st wave:neutrophils
| 2nd wave: macrophages
32
describe 1st wave removal by neutrophils
microbes and damaged tissues are ingested and destroyed through phagocytosis; neutrophils then quickly die via apoptosis
33
describe 2nd wave removal by macrophages
phagocytize remaining microbes, necrotic tissue, and dead neutrophils, cleaning up the mess that was made. macrophages also produce anti-inflammatory cytokines that begin to down regulate inflammation
34
how is inflammation regulated?
once activated, leukocytes have short half lives. anti- inflammatory signals are activated to down regulate inflammation
35
how does inflammation resolve?
leukocyte activation triggers proliferation and migration of fibroblasts to restore normal tissue function
36
what can go wrong with the inflammatory response?
too little inflammation, misdirected inflammation, inflammation in response to normally harmless substances, inflammation is excessively prolonged or repetitive
37
what can result from too little inflammation
infections go unchecked, wounds/tissues don't heal
38
what can result from misdirected inflammation
inflammation against body native tissues; autoimmune diseases
39
what can result from inflammation in response to normally harmless substances
hypersensitivity and allergies
40
what can result from excessively prolonged or repetitive inflammation
chronic inflammation
41
what is our role in examination revolving around inflammation
- observe: quality of inflammation & impact on movement/gait
- assess history: how it happened and the pain
- tests and measures: ROM, strength, Gait/movement, edema
42
what is edema?
excessive fluid in interstitial space
43
what are the key observations of edema
increased girth of body part, tight, shinny skin, indentation of skin under clothes, weeping/leaking
44
why is edema a problem?
interferes with normal movement (decreased ROM & control, pain) may indicate a health problem
45
what health problems could be indicated by inflammation
tissue injury, DVT, heart failure, liver or kidney disease
46
what are the 3 types of edema
inflammatory, non-inflammatory, effusion
47
what characterizes inflammatory edema
red, hot, painful; typically due to trauma, swelling or inflammatory reaction
48
what characterizes non-inflammatory edema
pitting: press into skin and pits form. has a variety of causes
49
what characterizes effusion
excess fluid enclosed in a space.
joint effusion = in capsule
pleural effusion = in pleural space
50
how can you describe edema
location, duration, inflammatory vs pitting, amount (girth/volume)
51
what is a typical prognosis of inflammation
1-2 weeks; if no change in signs/symptoms consider other factors such as repeated injury or other sources if inflammation
52
what is the goal in intervention for inflammation
to manage and promote healing
53
what is the main principle for inflammation intervention
```
POLICE
Protection
Optimal Loading
Ice
Compression
Elevation
```
54
what are the functional regions of a neuron
input, integrative, conductive, output
55
what is the major difference between a motor neuron and a sensory neuron in the PNS
sensory neurons have cell posies that lie just outside the spinal cord while motor neurons have sell bodies in the spinal cord
56
what is the job of the Endoplasmic reticulum
synthesis of lipids and vesicles
57
what is the job of the lysosome
digests glycogen to glucose; part of the axoplasmic transport system
58
what are the functions of an axon
1. transmission of information: propagation of AP
| 2. transportation of metabolically important materials to and from the soma to the axonal end
59
Describe myelinated axons in the PNS
myelinated by Schwann cells that enveloping them with up to 300 concentric layers forming myelin sheath
60
how do neurons transmit information within the neuron
action potential
61
how do neurons transmit information between neurons
synapse
62
what are the cellular mechanisms for neural transmission of information
resting membrane potential, post synaptic potential, action potential
63
what are the synaptic mechanisms for neural transmission of information
convergence and divergence
64
what are the behavioral mechanisms for neural transmission of information
feed-forward and feedback
65
what is the importance of resting membrane potential
regulates activation so that neurons do not randomly fire
66
what is the role of the cell membrane in resting membrane potential
creates a physical barrier keeping ion charges separate due to selective permeability
67
what are the two types of forces that guide movement of ions
electrostatic force and diffusion force
68
what is electrostatic force
like charges repel eachother
69
what is diffusion force
ions tend to move from higher concentration to low concentration
70
what are the types of mechanisms for ion transport
ion channels and active mechanisms
71
what are the types of ion channels
ligand gated - had a receptor that must be bound to open
mechanically gated - mechanical stress applied at level of channel open them
voltage gated - opens & closes at specific voltage across a membrane
leakage - randomly open for shits and gigs
72
what is the active mechanism for ion transport
Sodium potassium pump! requires ATP, transports 3 Na+ out and 2 K+ in against diffusion gradient
73
what is resting membrane potential (value)
-70mV
74
what is depolarization
the inside of the cell becomes less negative
75
what is hyperpolarization
inside of the cell becomes more negative (over shoots RMP)
76
what is a post-synaptic potential
graded potential, brief increase or decrease in membrane potential occurring in the post synaptic neuron; can cause action potential propagation if strong enough of via summation
77
what is an EPSP
excitatory post-synaptic potential; inside becomes more positive than resting, membrane becomes depolarized
78
what is a IPSP
inhibitory post-synaptic potential; inside becomes more negative than resting, membrane becomes hyperpolarized
79
what happens when ESPS reaches threshold?
and action potential fires
80
when do voltage gated sodium channels open and close
open at threshold (-55mV) and close at +30mV
81
when do voltage gated potassium channels open and close
open at +30mV, close much slower than sodium channel
82
when is the sodium potassium pump activated
around resting membrane potential
83
how do axons conduct information
action potential propagation
84
what is action potential propagation
diffusion of sodium atoms coming in moving down the axon creating a cyclic moving action potential
85
what are the functions of the myelin sheath
- acts as an electrical insulator for parts of the axon, thus preventing action potential form developing
- allows for accumulation of charge at the nodes of Ranvier
- speeds up conduction of action potential
86
what happens in MS
myelin is degraded which leads to slow action potentials of formerly fast neurons
87
what is the relationship between action potential speed and axon diameter
the greater the diameter the faster AP conduction
88
what is the physical function of the spinal cord
two way link between the brain and the periphery
89
how many pairs of spinal nerves are there
31
90
are spinal nerves sensory or motor
neither! they're mixed!
91
what are the spinal cord enlargements
cervical and lumbar
92
from what spinal nerves does the brachial plexus arise
C5-T1
93
from what spinal nerves does the lumbar plexus arise
L1-S4
94
from what spinal nerves does the sacral plexus arise
L5-S4
95
what are the connective tissue layers in a nerve
epineurium - around entire nerve
perineurium - around a fascicle
endoneurium - around a single axon
96
what is arthrology
the study of the classification, structure, and function of joints
97
how does movement occur
through sequenced rotations around the joints
98
what 2 ways can you classify joints
based on movement potential and based on mechanical analogy
99
what are the two wats to describe/classify joints based on movement potential
synarthroses & diarthroses
100
what is a synarthroses
joint that allows little to no movement
101
what are the 3 types of synarthroses
fibrous - skull
cartilaginous - pubic symphysis & intervertebral discs
syndesmosis - ulna/radius & tibia/fibula
102
what is the function of synathrodial joints
transfer forces between bones
103
what is a diarthrosis
joint that allows moderate or extensive motion, AKA synovial
104
what are the 7 elements of all synovial joints
1. articular cartilage
2. joint capsule
3. synovial membrane
4. synovial fluid
5. ligaments
6. blood vessels
7. sensory nerves
105
what is articular cartilage
cartilage that covers the articular surface of the bone
106
what is a joint capsule
a connective tissue "envelope" that encloses the joint; has 2 histologically distinct layers
107
what are the 2 layers of the joint capsule
outer layer = dense connective tissue
| inner layer = synovial membrane
108
describe the synovial membrane
inner layer of the capsule, ~3-10 cell layers thick, highly innervated. composed of specialized cells that produce synovial fluid
109
describe synovial fluid
fluid secreted bu the synovial membrane, contains hyaluronan and glycoproteins; lubricates joint surfaces and provides nourishment to articular cartilage
110
describe the structure and function of ligaments
connective tissue that joins two bones, prevents excessive movement.
111
what are the 2 types of ligaments
capsular & extracapsular
112
describe capsular ligaments
distinct thickening of a joint capsule, broad sheets of fibers, resist movement in multiple planes
113
describe extracapsular ligaments
cord like structures, partially or completely separate from joint capsule; resists movement in 1 or 2 planes
114
how do blood vessels play into synovial joints
blood vessels penetrate the capsule & extend to junction of fibrous and synovial layer
115
how do sensory nerves participate in synovial joints
innervate external and internal capsular layer providing the ability for pain and proprioception
116
what are accessory synovial joint structures
- intra-articular discs or menisci
- peripheral labrum
- fat pads
- bursae
- synovial plica
117
describe the structure and function of articular discs/menisci
made of fibrocartilage, increases joint congruency which increases stability, provides shock absorption
118
describe the structure and function of peripheral labrum
fibrocartilage structures, extend around the periphery of the joint, deepens joints cavity and supports capsular attachment.(hip and shoulder)
119
describe the structure and function of fat pads
reinforces capsule & fills in recesses in the joint, often interposed between fibrous layer and synovial membrane, cushions surfaces to reduce forces
120
describe the structure and function of bursae
extension or outpouching of synovial membrane, filled with synovial fluid, cushions and prevents friction between moving tissue surfaces
121
describe the structure and function of synovial plicae
redundancy or folds in synovial membrane; redundancy is necessary to prevent undue tension during motions
122
what are the classifications of synovial joints based on movement potential
hinge joint, pivot joint, ellipsoid joint, ball and socket joint, plane joint, saddle joint, condylar joint,
123
describe a hinge joint
single action of rotation; motion occurs perpendicular axis of rotation (ex: ulnar humeral joint)
124
describe a pivot joint
single axis of rotation; rotation occurs parallel to the axis of rotation (ex: radial ulnar joint)
125
describe an ellipsoid joint
two axes of rotation; one side elongated concave and other side elongated convex; bi-planar motion flexion/extension & abduction/adduction; limits spin motion at joint (ex: wrist)
126
describe ball and socket joint
3 axes of rotation; spherical convex surface & cup like concave socket; allows 3 degrees of freedom for joint angular motion (ex: iliofemoral joint)
127
describe a plane joint
lack a definitive axis of rotation; sliding and rotation of one surface on the other (ex: carpals on metacarpals)
128
describe a saddle joint
2 axes of rotation; perpendicularly oriented convex and concave surfaces; allows ample bi-planer motion but limits spin (ex: thumb)
129
what is an axis or rotation
fixed; all points experience equal rotation; instantaneous
130
describe factors of mechanism of injury (MOI)
trauma or insidious onset; potential movements and forces which leads to tissues susceptible to damage
131
what is a force
a push or pull that produces, arrests or modifies movement
132
what is a torque
the product of a force and its moment arm (rotational force)
133
what is a load
a force that acts on the body
134
what are externally derived loads acting on the body
gravity, impact, friction, wind
135
what caused internally derived load on the body
muscle activation & tissue deformation
136
what is tissue deformation
tissues deform with load to match external forces
137
how do healthy tissues respond to load?
healthy tissues deform to adjust to load but resist structure and shape change there for they return to homeostatic shape after load is removed
138
what determines the load response
the type of tissue/ strength of tissue
139
what is tissue stress
force/load generated within the tissue to resist deformation divided by its cross sectional area; measures stored energy of a tissue
aka pressure
140
what is tissue strain
the amount a tissue deforms under a force/load; usually expressed as % or distance though it is truly unit-less
141
what is the toe region of a stress strain curve
tissue is slack, the stress results in a removal of slack
142
what is the linear region of the stress strain curve
period where the tissue is becoming loaded, slope = stiffness of the tissue
143
what is young's modulus
slope of the linear region of the stress strain curve; tissue stiffness
144
what happens after tissue deformation in the elastic/linear region of the stress strain curve
- the tissue returns to its original shape/length after loading
- all stored energy is released with unloading
145
what is the yield point on the stress strain curve
the transition point between elastic and plastic behavior, tissue permanently changed when you pass the yield point; not always a bad thing
146
what is plastic deformation
overstrained tissue permanently damaged, plastic deformation energy cannot be recovered once load is released
147
what is the ultimate failure point of the stress strain curve
the point at which the tissue fails and us unable to hold additional load
148
what is tissue viscosity
the fluid like component of tissue behavior; it is time dependent
149
what is tissue elasticity
the ability of a tissue to return to its original shape after loading
150
how is the behavior of tissues discribed
viscoelastic; depends on the tissue and what makes it up
151
what is creep
mechanical behavior of a tissue related to viscoelastic; continued deformation of a tissue over time as it is subject to a constant load
152
what are the factors that impact musculoskeletal loads
magnitude, rate, and type
153
how does a tissue react to loading rate
tissues are sensitive to rate; tissues behave differently under different loading rate conditions (ex: high vs low velocity ACL tear)
154
what are the types of musculoskeletal loads
tension, compression, bending, shearing, torsion, combined loading
155
describe tension loading & injury example
pull of two forces on a tissue in opposite directions; lateral ankle ligaments severely tensioned as the foot rotates inward
156
describe compression loading & body example
forces that push or pull the surfaces of objects together or brings the end of an object closer; humerus is pulled against the glenoid by the deltoid muscle creating a compressive load between bones
157
describe bending loading & body example
tissue deformation that occurs at right angles to its longitudinal axis; concave side undergoes compression load, convex side undergoes tension load; coxa vara results in increased bending load on the neck of femur
158
describe shear loading & body example
unaligned parallel forces that move on part of a body in one direction and another part in opposite direction; femoroacetabular impingement creates abdormal shear load between the demur and acetabulum
159
what is tissue deformation
tissues deform with load to match external forces
160
how do healthy tissues respond to load?
healthy tissues deform to adjust to load but resist structure and shape change there for they return to homeostatic shape after load is removed
161
what determines the load response
the type of tissue/ strength of tissue
162
what is tissue stress
force/load generated within the tissue to resist deformation divided by its cross sectional area; measures stored energy of a tissue
aka pressure
163
what is tissue strain
the amount a tissue deforms under a force/load; usually expressed as % or distance though it is truly unit-less
164
what is the toe region of a stress strain curve
tissue is slack, the stress results in a removal of slack
165
what is the linear region of the stress strain curve
period where the tissue is becoming loaded, slope = stiffness of the tissue
166
what is young's modulus
slope of the linear region of the stress strain curve; tissue stiffness
167
what happens after tissue deformation in the elastic/linear region of the stress strain curve
- the tissue returns to its original shape/length after loading
- all stored energy is released with unloading
168
what is the yield point on the stress strain curve
the transition point between elastic and plastic behavior, tissue permanently changed when you pass the yield point; not always a bad thing
169
what is plastic deformation
overstrained tissue permanently damaged, plastic deformation energy cannot be recovered once load is released
170
what is the ultimate failure point of the stress strain curve
the point at which the tissue fails and us unable to hold additional load
171
what is tissue viscosity
the fluid like component of tissue behavior; it is time dependent
172
what is tissue elasticity
the ability of a tissue to return to its original shape after loading
173
how is the behavior of tissues discribed
viscoelastic; depends on the tissue and what makes it up
174
what is creep
mechanical behavior of a tissue related to viscoelastic; continued deformation of a tissue over time as it is subject to a constant load
175
what are the factors that impact musculoskeletal loads
magnitude, rate, and type
176
how does a tissue react to loading rate
tissues are sensitive to rate; tissues behave differently under different loading rate conditions (ex: high vs low velocity ACL tear)
177
what are the types of musculoskeletal loads
tension, compression, bending, shearing, torsion, combined loading
178
describe tension loading & injury example
pull of two forces on a tissue in opposite directions; lateral ankle ligaments severely tensioned as the foot rotates inward
179
describe compression loading & body example
forces that push or pull the surfaces of objects together or brings the end of an object closer; humerus is pulled against the glenoid by the deltoid muscle creating a compressive load between bones
180
describe bending loading & body example
tissue deformation that occurs at right angles to its longitudinal axis; concave side undergoes compression load, convex side undergoes tension load; coxa vara results in increased bending load on the neck of femur
181
describe shear loading & body example
unaligned parallel forces that move on part of a body in one direction and another part in opposite direction; femoroacetabular impingement creates abdormal shear load between the demur and acetabulum
