Intro to Neuropathology

Question 1

percentage of genes coding for nervous system-related proteins

Answer 1

50%

Question 2

selective vulnerability of the hippocampus

Answer 2

hypoxic/ischemic changes

Question 3

selective vulnerability of the caudate nucleus

Answer 3

Huntington’s disease

Question 4

selective vulnerability of the motor neurons

Answer 4

amyotrophic lateral sclerosis (ALS)

Question 5

selective vulnerability of substantia nigra

Answer 5

Parkinson’s disease

Question 6

type of neurons most resistant to injury

Answer 6

astrocytes

Question 7

selective vulnerability of oligodendria

Answer 7

myelin disorders

Question 8

3 types of glial cells

Answer 8

astrocytes, oligodendocytes, ependymal cells (NOT microglia)

Question 9

if needed, microglia can transform into ..

Answer 9

histiocytes

Question 10

Nissl substances are representative of

Answer 10

rough endoplasmic reticulum

Question 11

what part of the neuron stains with H&E?

Answer 11

nucleic acids

Question 12

major mechanisms of cellular injury

Answer 12

free radical injury, excitotoxic injury

Question 13

examples of excitotoxic injury

Answer 13

glutamate, aspartate; depolarization; NMDA amino acid receptor

Question 14

*what is the mechanism of excitotoxic injury?

Answer 14

injured neurons release their excitatory NTs (glutamate), which results in depolarization of the surrounding neurons through the inappropriate activation of NMDA receptors

Question 15

how can you protect against excitotoxic injury?

Answer 15

antioxidants

Question 16

excitotoxic injury via NMDA receptors results in..

Answer 16

calcium influx that interferes with mitochondrial function which eventually leads to cell death

Question 17

characteristics of acute neuronal injury

Answer 17

eosinophilic necrosis (red), hypoxic injury, shrunken cytoplasm, dark smudgy chromatin, irreversible cell death

Question 18

how long does it take for acute neuronal injury to show up on light microscopy?

Answer 18

12 hrs

Question 19

hippocampus CA1 region (Sommer’s sector) is most sensitive to what type of injury?

Answer 19

hypoxic-ischemic

Question 20

subacute and/or chronic type of neuronal injury

Answer 20

degeneration

Question 21

the changes that occur in the neuron body in response to axonal injury is termed..

Answer 21

axonal reaction (formerly known as central chromatolysis); regenerative attempt

Question 22

examples of axonal reaction

Answer 22

damage to axon, margination of Nissl substance, central clearing of the cytoplasm, peripheral displacement of the nucleus, rounding of the cell body

Question 23

term for when an axon is transected, and the proximal portion starts to regenerate and myelinate

Answer 23

Wallerian degeneration

Question 24

if the BM is not intact during Wallerian regeneration, what is the outcome?

Answer 24

chaotic proliferation of axons, resulting in a painful nodule called traumatic or amputation neuroma

Question 25

how are neuromas treated?

Answer 25

can be anastomosed to facilitate healing, or if damage is extensive, nerve transplantation can be done

Question 26

what are axonal spheroids and how do they form?

Answer 26

when an axon is transected, the transport material going towards the synapse will accumulate at the site of injury

Question 27

identification of axonal spheroids on path slides is important because..

Answer 27

it helps confirm presence of an infarct next to them; also in the diagnosis of such things as diffuse axonal injury

Question 28

stain used to highlight axonal spheroids/swelling

Answer 28

silver stains

Question 29

most common neuronal inclusion

Answer 29

viral inclusion

Question 30

a neuronal inclusion seen with Parkinson’s disease pathology

Answer 30

Lewy body

Question 31

inclusion seen in Pick’s disease/frontotemporal lobar degeneration

Answer 31

Pick’s body

Question 32

inclusion seen in alzheimer’s

Answer 32

neurofibrillary tangles (accumulate in the cytoplasm)

Question 33

what is trans-synaptic degeneration?

Answer 33

secondary degeneration of a neuron connected to a dying neuron; can be counter-intuitive; anterograde or retrograde

Question 34

what physically happens to astrocytes when they react?

Answer 34

develop plump cytoplasm, processes become more prominent; indicates some pathology

Question 35

inclusions representative of a hyperammonemia typically seen with cirrhosis

Answer 35

Alz type II glia (astrocytes)- nothing to do with Alz

Question 36

astrocyte pathology typically seen with demyelinating diseases like MS

Answer 36

Creuzfeldt astrocyte

Question 37

neuronal inclusion made of GFAP and B-crystalline

Answer 37

Rosenthal fibers (slow-progressing, in the cytoplasm)

Question 38

fried egg appearance

Answer 38

oligodendrocytes

Question 39

oligodendrocyte inclusions are seen in this disease

Answer 39

progressive multifocal leukoencephalopathy

Question 40

the diagnostic value of oligodendrogial changes

Answer 40

satellitosis around neurons and blood vessels by the neoplastic cells infiltrating grey matter areas.

Question 41

two major changes associated with reactive microglia & what they’re associated with

Answer 41

microglial nodules, neuronophagia; most commonly associated with viral infections of the CN

Question 42

PNS biopsies are usually taken from the..

Answer 42

sural nerve (entirely sensory)

Question 43

pathologic characteristic of Charcot-Marie-Tooth disease

Answer 43

“onion bulb” Schwann cell in the PNS resulting from constant remyelination and demyelination

Question 44

technique using chemical reactions to highlight certain tissue components like mucin, myelin, collagen

Answer 44

histochemistry

Question 45

special staining technique for astrocytes using antibodies raised against specific components of cells

Answer 45

immunohistochemistry

Question 46

in-situ hybridization is used to show the presence of

Answer 46

DNA segments