Test 1 Flashcards
when can frozen tissue sections be used?
when an urgent tissue diagnosis is needed, unexpected nodule during surgery, presence of matastasis beyond a proposed resection field
can you see fine details better in a routine section of tissue or a frozen section?
routine section, but the frozen section can be completed quickly
direct method of immunocytochemistry
less sensitive technique; tag an antibody with a marker; this antibody tags the antigen and you view the sample under a fluorescent microscope
indirect method of immunocytochemistry
more sensitive technique; apply antibody to antigen; the first antibody is then tagged with another antibody; this amplifies the signal by attaching more antibodies to the antigen; view under fluorescent microscope
what does anticytokeratin immunoperoxidase technique reveal?
tumor originates from epithelial cell and possesses cytokeratin
what antigen marker is specific to lymphatic vessels?
D2-40
in situ hybridization
try to find a specific genetic sequence to a given sample; the complimentary sequence is tagged with fluorescent marker to tag the sequence
if you are positive for TTF1, what does this suggest
cancer of the lungs, specifically adenocarcinoma
Creutzfeldt-Jakob disease
caused by prions; ataxia, paralysis, dementia, and eventually death
antagonist
a signal that blocks the normal extracellular signal
agonist
mimic the effect of a signal
up and down regulation of receptors
receptors are not static; they can be upregulated if the signal is present in decreased amounts; they ca be down regulated in response to increased signals
estrogen receptors
estrogen receptors are found in the nucleus
macropinocytosis
an active process that internalizes substances via microfilaments from outside of the cell; the process by which salmonella typhimurium infects the body; also utilized by thyroid hormones and immune cells
non-clathrin/noncaveolar
a transport mechanism that uses a vesicle to move substances in the cell; the vesicle has neither a clathrin or caveolae coat; the method by which cholera ans shiga toxin enter the cell
explain clathrin-mediated receptor endocytosis
- cargo protein interacts with cargo receptor 2. formation of coated pit around receptors 3. formation of coated vesicle (cathrin) in a GTP dependent reaction that uses dynamin 4. vesicle is internalized 5. coat breaks down 6. uncoated vesicle ready to use, including cargo
how does LDL move into the cell?
clathrin-mediated receptor endocytosis; the receptor can be mutated so that the coated vesicle cannot form, ultimately leading to atherosclerosis
phagocytosis
cell internalizes large substances; typically is mediated by receptors; bacteria attaches to receptors and is internalized into a phagosome; when in the cell, lysosomes can break down the bacterium; this can also occur with nonbiologic material
what are 3 secretion processes?
exocytosis, porocytosis, exosomes and exosome-like vesicles
what are the 2 pathways of exocytosis?
regulated pathway and constitutive pathway
explain the constitutive pathway
the cell is constantly producing vesicles for secretion only, never for storage
explain the regulated pathway
FINISH THIS
explain porocytosis
method that releases NT into synapse FINISH THIS
explain exosomes