Exam 2 Flashcards Preview

Biomaterials > Exam 2 > Flashcards

Flashcards in Exam 2 Deck (61):
1

Calcium (Phosphate/Sulfate) is a main component of _____

PHOSPHATE!

Bone

2

Integrins are

intracellular transmembrane proteins that Govern signals and cell growth, FACILITATE FOCAL ADHESIONS

NOT Differentiation

3

Endothelial cells in the _______ layer of a blood vessel experience shear stress as blood flows through the vessel

Tunica INTIMA contains endothelial cells

Tunica Media = Muscle cells

Tunica Adventitia contains fibrous collagen

4

Bioactive materials act to elicit

specific biological responses at the tissue/material interface in attempts to enhance bond formation

5

Osteoinductivity is the ability of a material to:

encourage osteoCLAST attachment and migration

Osteoconductivity = OsteoBLAST

6

The 3D structure of a protein can influence the function of the protein

True

7

Hydrogel swelling can be activated by

pH, temperature or electric field

8

Surface topography (roughness) of a biomaterial can influence

cell attachment

9

Secondary Ion Mass spectroscopy allows analysis of surface based on

mass + charge ratio
or mass + ion composition
or mass and functional groups

10

Experimental data has shown that fluid flow over osteoblasts can

align actin filaments

11

Complements are (Intracellular/proteins in the bloodstream) that are capable of activating the immune system

PROTEINS IN THE BLOODSTEAM

not intracellular

12

Surface modification at the nanolevel is a

top down approach

Surface mod = top down

Bottom up is when the whole thing is nano

13

Size of imprint in photolithography depends on

The wavelength of the beam

14

The pattern of focal adhesions is dictated by

nanoscale surface features

15

Nanocrystalline hydroxyapatite enhances

bone growth in vivo

16

When testing the release of drug from a degradable polymer, temperature IS important because

It influences rate of diffusion and degradation and thus drug delivery

17

Growth factors affect:

Cell growth, proliferation, AND DIFFERENTIATION

18

Experimental data discussed has shown that dynamic loading:

HAS an effect on the rate of bone repair (Wolff's law)

19

Nanoscale material surfaces can cause

altered protein adsorption

20

In general, it is advisable to obey the hierarchical structure of tissue when designing a tissue engineering scaffold

True

21

Contact angle measurement is a way of directly determining strength of adhesion between a cell + substrate

False! It is to determine the hydrophilicity or hydrophobicity of a material


and it is SURFACE characterization

22

Experimental data has shown that all drugs are delivered at the (Same/different) rate when incorporated into (CPP:SA) polymers

Different

23

Actin expression (can/cannot) be influenced by the physical forces associated with fluid flow

CAN

24

The (Yield/Ultimate) stress is indicative of the max load a material can sustain prior to failure

ULTIMATE

Yield stress is point between elastic/plastic

Elastic modulus is

25

Nanotechnology encompasses:

Any material with at least 1D below 1um in measure, any material between 1-100 nm in length, any material between 1-1000 nm in length

ALL of the ABOVE

26

Which of the following is not a type of cell-matrix adhesion:

A. Microtubule
B. Fibrillar adhesion
C. 3D matrix adhesion
D. Focal adhesion

A. Microtubule

it is in the cytoskeleton not the matrix at all

27

Which characterization method involves analysis of construct's pore structure

Mercury Porosimetry

Not SEM or FTIR spec

28

Top-down approach of nanoscale biomaterials development:

Modification of structures larger than nano
NOT Nanotubes

29

Bottom up approach of nanoscale development:

Involves formation of structures originating at the nanoscale size level

AND the nanotubes one - unless there's no answer with both, in that case select "involves formation of structures that originate at nanoscale level"

30

Altering the ratio of CPP:SA can influence what

Influence rate of degradation of the polymer
AND
Influence rate of Drug delivery

But it does NOT control rate of biocompatibility of the polymer

Careful, it's B and C if it's about rate of delivery/degradation, but NOT if it is about biocompatibility!

31

T/F : Cytoskeleton's only function is to provide strength to the cell

THIS IS FALSE!

It also allows for structure and transport of molecules for signaling and sensing

32

Cytoskeleton composed of:

Composed of 3 different proteins: Actin microfilaments, Intermediate filaments, and microtubules

33

Where are actin microfilaments found?

Mostly just below the plasma membrane

**Might be the one that's false though, do process of elimination, and look out for the word "ONLY"

34

ECM is communicated to the nucleus via the cytoskeleton (T/F)

True

35

Which statement is true about the body and bone

Body responds to weightlessness by DECREASING bone formation due to the LACK of mechanical forces applied to the skeletal system

Watch out, this may change on the exam ---

36

Which statement is true about the body and bone Scenario 2 - Flexible/inflexible vessel

When designing a synthetic vessel, you need a FLEXIBLE compliant structure to minimize smooth muscle cell proliferation at the anastamosis between the native vessel and synthetic vessel

37

T/F: Foreign body giant cells are indicative of a non-inflammatory response

False

It IS an inflammatory response

38

Which statements are true about inflammation:

Neovascularization is part of the wound healing process

Newly formed vessels are part of granulation tissue

Simple implantation of biomaterial constitutes a would and therefore initiates the wound healing response

All true!

39

Which 3 intracellular components contribute to the mechanical integrity

Microtubules
Actin microfilaments
Intermediate filaments

Integrins are cell-ECM attachments

40

Which method of surface analysis provides a unique fingerprint

X-ray diffraction
Also FTIR

41

What is NOT a function of the ECM

Provide energy for intracellular protein production

is NOT a function of the ECM

42

Functions of the ECM

Facilitate cell-cell communication
Store and release important molecules
Aid in cell attachment

43

Which method is not related to surface analysis

Gel permeation chromatography

44

Which methods are for surface analysis

FTIR
Xray photoelectron spec
Secondary ion mass spec

45

Tissue response to inert materials involves

Thin fibrous capsule formation

NOT:
foreign body giant cells/inflammation
Slow healing

46

3 complications associated with biomaterials

1. Biodegradation effects in body (toxicity)
2. Calcification
3. Inflammation, reduction in blood flow and pain

47

2 Reasons why in vivo testing is important

1. See the negative effects of material on the body in controlled realistic conditions

2. See if the desired effect is achieved in controlled realistic conditions

48

2 Mechanisms through which nanotubes can be used as drug delivery vehicles

1. Filling the hollow nanotube w/ drug
2. Attach drug to surface of nanotube

49

Advantages of nanotubes vs. other strategies

Carbon Nanotubes are good conductors and have good mechanical properties (strong). Also, they are permeable to cell membrane and can reach destinations that other materials cannot.

50

What 2 parameters control the nanofiber dimensions during the process of electrospinning and how does manipulating these alter the nanofibers produced?

The NEEDLE GAUGE can affect the size of nanofibers formed - smaller/narrower needles = LARGER nanofibers, and vice versa. -- CAREFUL - small needles = larger fibers

Increasing the CONCENTRATION OF MATERIAL in the solvent will INCREASE the diameter of the nanofiber formed.

51

What is focal adhesion and what is role in transmitting extracellular signals to the intracellular environment?

Focal adhesions are made of integrins and cadherins and allows for the transmission of signals to the cell from the ECM. Integrins produce FA complexes, and adherins/cadherins anchor FAs to the actin cytoskeleton.

MHC-I involves focal adhesion proteins for INTRACELLULAR interactions while MHC-II involves focal adhesion proteins with EXTRACELLULAR interactions.

52

2 Advantages of nanoparticles for drug delivery

1. Nanoparticles have more similar size to biomolecules
2. The produce no immune response since they can pass through the cell membrane
3. They can make dosing more manageable and target specific areas (like low pH areas for cancer cells.)

53

What is rationale for using nanofibers as scaffolds for tissue engineering?

Nanofibers can be created using electrospinning or reverse self-assembly.
Nanofibers increase surface area to allow for increase in CELL PROLIFERATION, CELL ADHESION, and PROTEIN ADSORPTION.

54

3 Characterization techniques, surface or bulk- and what they inform on

1. Mercury porosimetry - bulk - uses mercury to determine the pore structure of material

2. FTIR - Surface - samples functional groups on the outside surface - can determine what type of sterilization to do

3. Contact angle goniometry - surface - determine the hydrophilicity of a substance. Low angle = hydrophilic

55

2 Advantages to delivering peptides from a biomaterial rather than proteins?

1. Peptides do not have an exact form - more adaptable to the body. Proteins have a set structure and cannot adapt as well.

2. Peptides more readily received by the cell membrane and produce no immune response. Peptides allow for smoother delivery with less immune response.

56

Surface (Smoothness/roughness) promotes faster blood coagulation

ROUGHNESS

57

3 different in vitro cell proliferation assays

1. Colormetric assays
2. Dead cell assays
3. Cytometer

58

2 reasons why in vitro testing is important

1. Parameters like temperature or acidity can be controlled
2. Cell proliferation and adhesion can be tested before a live specimen is used.

59

3 Mechanisms by which nanostructured surfaces modulate cell functions

1. Surface roughness can alter protein adsorption + promote blood coagulation
2. High surface area/volume ratio, improves cellular uptake
3. Very small size, can permeate the cell membrane and have targeted delivery of active ingredient

60

5 different types of innate immune systems

What do they mean? Option 1 is the immune responses -->

1. Minimal response - thin collagenous membrane, response to PTFE and ceramics
2. Chemically induced acute - absorbable sutures + thermoset resins
3. Physically induced - particulates of PMMA or nylon
4. Chromic severe inflam. - degradable materials w/ toxins or metal particulates
5. Necrotic response = premature death of cells - bone cement or surgical additives -

61

5 different types of immune systems

Ask what they mean, cells or responses?
option 2 - types of cells

1. Natural killer cells - detect low levels of MHC I
2. Mast cells - Release histamine + heparin
3. Neutrophils - inhibit growth of pathogens
4. Foreign body giant cell - collection of fused macrophages - Chronic inflammation/large foreign bodies
5. Macrophages - Phagocytize pathogens
6?. Eosinophils - release granules like neutrophils