Testing Host Responses
Though many biomaterials have decades of regulatory history, chemical characterization tests are still carried out to quantify these in medical devices
Leachables and Extractables
When an investigator interprets study results in a manner that conforms to their preconceptions towards a hypothesis, this represents what kind of bias?
Confirmation Bias
Hydrolytic-mediating factors (e.g ions, water, etc.) typically occur in this order
Water -> ions -> proteins
Besides clotting time, the Osorio group also analyzed this principle component of blood compatibility
Hemolysis
In uniaxial tension, a material elongates by 2% along its length and contracts by 0.5% in width. This ratio, often denoted by ν, quantifies the lateral strain relative to axial strain
Poisson’s ratio
Highest concentration measured where NO significant response was detected
No-observable adverse effect level (NOAEL)
The disproportionate reporting of positive, favorable research is what kind of bias?
Publication bias
These are the two main branches of chemically-induced biodegradation
Oxidative and Hydrolytic
In analyzing the degradation of their GelMA hydrogel in the presence of nHAp, Thakur et a. used this biologicially-relevant enzyme
Collegenase
Polymers with a high degree of this molecular arrangement are less susceptible to hydrolysis, as tightly packed chains limit water's access to hydrolyzable bonds
Crystallinity
This type of tests analyses the rupture of red blood cells spectrophotometrically
Hemolysis
What was the fundamental statistical measure used by the NEJoM studies to evaluate the potential complications of breast implants
Relative Risk
What natural, biologic process (in benign cases) naturally hinders biodegradation
foreign body capsule
In the Likhitpanichkul et al. paper (JD #3), the authors tested for the presence of this cell signaling molecule, an indicator of inflammation, matrix degradation, and localized apoptosis
Nitric oxide/Nitrite
These bacterial communities form protective barriers on implant surfaces, making infections harder to treat unless antibiotics are administered early
biofilms
This type of clot, abundant in fibrin and platelets, forms in veins as opposed to arteries
Red thrombus
Having already been marketed and sold prior to the 1976 MDA, breast implants received this “benefit”, relieving them temporarily of immediate regulatory scrutiny
They were grandfathered in
Immune cells typically induce hydrolysis via these compounds
Enzymes
Because of its superior blood-compatibility characteristics, the ISO 10993-12 standard requires what synthetic material to be used as a negative control for biocomp studies?
HDPE
Once activated by thrombin, platelets release these two compounds, further activating more platelets in a positive feedback look process.
APD and Thromboxane
The ratio of an established tox threshold to the leachable dose in a biomaterial, or this, is the primary metric in a toxicological risk assessment
Margin of Safety (MoS)
A study whose results can only be applied in a limited capacity to situations outside of the study conditions represents what kind of bias?
External validity
Polymeric devices whose biodegradation is dominated by surface erosion typically follow this degradation profile
Zero-order
In the Likhitpanichkul et al. paper (JD #3), the authors evaluated cytotoxicity visually using this combination of dyes/stains
MTT and DAPI
In a typical AMES assay to test for mutagenicity, mutations of either Salmonella or E. coli are typically starved of this amino acid
Histadine