Week 12 - Neurological Disorders

Question 1

What term describes the process of cancer cells moving to other parts of the body?

Answer 1

Metastasis.

Question 2

Describe the differences between benign tumors and malignant tumors.

Answer 2

Benign Tumors:

• encapsulated
• non-cancerous
• usually removeable
• commonly don’t reoccur
• do not spread

Malignant

• cancerous and invade or damage nearby tissues
• metastasize

Question 3

Describe the process of metastasis (cells moving to other parts of the body) may occur. What problems may cells face during this process?

Answer 3

Cells leave original tumor and invade vessels throughout body. They then stop in various places and form a new tumor there.

Problems cells may face are:

• dying due to bumping around the blood vessels and squeezing through tight spaces
• immune system killing them
• just not being strong enough to survive floating around in the bloodstream

Question 4

If benign tumors are non-cancerous and do not spread to other parts of the body, how are they dangerous? Give an example of an illness that occurs as a result of this danger?

Answer 4

They may cause compression to surrounding tissue. Hydrocephalus (compression of the cerebrospinal fluid) is an example of a compressing illness.

Question 5

True or false: Tumors can develop from any type of cell.

Answer 5

False. Tumors can NOT develop from neurons.

Question 6

Differentiate between the two major types of brain tumors?

Answer 6

(1) Primary Tumors
- tumors that start in the brain and then invade other parts of the body

(2) Secondary Tumors
- tumors that start in other parts of the body and then invade the brain

Question 7

What are the 2 most dangerous types of brain tumors and what type of tumor are they?

Answer 7

(1) Gliomas
(2) Metastatic Carcinoma

Both are primary tumors.

Question 8

Which term describes a period of sudden excessive activity in the cerebral neurons (neurons in the brain)?

Answer 8

Seizure.

Question 9

Which term describes the uncontrollable movement of the muscles that can happen as a result of a seizure?

Answer 9

Convulsions.

Question 10

Which type of seizure disorder is characterized by having a single episode of a seizure, that elicits a series of seizures, without the ability to regain consciousness? What is its treatment?

Answer 10

Status Epilepticus.

Treatment may include:

• anticonvulsive drugs that increase inhibitory processes (increasing GABA)
• keto diet
• brain surgery if nothing else works

Question 11

What are the two types of seizures?

Answer 11

(1) Generalized Seizures
- no local onset, so it is hard to detect where they are stemming from

(2) Partial Seizures
- seizures that stem from a specific area in the brain

Question 12

What are the 3 types of Generalized seizures in order of most severe to least severe? Briefly describe each.

Answer 12

(1) Tonic-Clonic (Grand Mal)
- contains four phases: an aura, then the tonic phase (stretching of the muscles), then the clonic phase (convulsions of the muscles), then sleep

(2) Absence (Petit Mal)
- common in children
- may include zoning out and staring off into space for brief moments
- can be misdiagnosed because teachers may see these children and simply inattentive and unmotivated in school

(3) Atonic
- temporary paralysis

Question 13

What are the two types of partial seizures?

Answer 13

(1) Simple
- change in consciousness

(2) Complex
- loss of consciousness

Question 14

What are the 2 types of strokes? Which one is more common? Which one is more lethal?

Answer 14

(1) Hemorrhagic
- bleeding in the brain
- more lethal than ischemic/obstructive strokes

(2) Ischemic/Obstructive
- plugging / clogging of blood vessels that prevent blood flow to the brain
- more common (makes up 80% of strokes)

Question 15

What are the two types of hemorrhagic strokes?

Answer 15

(1) Intracerebral
- occurs inside the brain

(2) Subarachnoid
- occurs when blood vessels on surface of brain rupture and bleed between the brain and skull

Question 16

What are the 4 types of treatments for strokes? Include what each of them do, an example of each, and which type of stroke they treat (hemorrhagic or ischemic).

Answer 16

(1) Anti-hypertensives (eg. beta-blockers)
- decreases blood pressure
- used for both hemorrhagic and ischemic strokes

(2) Anticoagulants (eg. coumadin)
- blood thinners
- only for ischemic strokes, not hemorrhagic because thinning blood causing risk of more bleeding

(3) Clot dissolving drugs (eg. tPA, DSPA)
- meant to be used WHILE someone is having a stroke
- used for ischemic strokes

(4) Surgery (eg. carotid endarterectomy)
- meant to remove the plaque that is clogging blood vessels
- used for ischemic strokes

Question 17

Which developmental disorder has characteristics of a smooth philtrum, thin upper lip, and is caused by the mother ingesting alcohol during pregnancy?

Answer 17

Fetal Alcohol Syndrome

Question 18

Which developmental disorder can develop as a result of the mother getting rubella within the first 20 weeks of her pregnancy?

Answer 18

Congenital Rubella Syndrome.

Question 19

Which genetic (inherited) metabolic disorder is characterized by a lack of the enzyme that converts phenylalanine (phe) into tyrosine, leading to a buildup of phe and impedes myelination of neurons in the CNS? What is its treatment?

Answer 19

Phenylketonuria (PKU)

If blood tests suggests child has PKU, they are put on low phe diet and Kuvan (aka. sapropterin)

Question 20

Which genetic (inherited) metabolic disorder is characterized by swelling of the brain due to dysfunction of the lysosomes, and is associated with a recessive gene on chromosome 15?

Answer 20

Tay-Sach’s disease

Question 21

Which genetic mutation includes an extra copy of chromosome 21?

Answer 21

Down Syndrome

Question 22

List the 6 diseases that lead to the degeneration of neurons.

Answer 22

(1) Transmissible Spongiform Encephalopathies (TSE)
(2) Parkinson’s Disease
(3) Huntington’s Disease
(4) Alzheimer’s Disease
(4) Amyotrophic Lateral Sclerosis
(5) Multiple Sclerosis

Question 23

Define proteopathy. Which degenerative disorders occur as a result of proteopathy and which proteins are affected?

Answer 23

Proteopathy: The misfolding and clustering of healthy proteins into abnormal proteins, transforming the surrounding proteins into abnormal forms as well, demonstrating a domino effect

Proteopathy is seen in

• TSE
• Parkinson’s Disease (alpha-synuclein)
• Alzheimer’s Disease (abeta protein)
• Huntington’s Disease (HTT protein)
• ALS (SOD1 protein)

Question 24

What evidence is there that prion protein (PrPC) is important for neuronal survival?

Answer 24

• PrPc important for proliferation of neurons in the hippocampus
• PrPc mutations lead to developmental abnormalities and decreased proliferation

Question 25

What are some of the genetic characteristics of someone with Parkinson’s disease? What symptoms do these genetic characteristics result in, and what do both of these symptoms together lead to?

Answer 25

• proteopathy of alpha-synuclein protein on chromosome 4 (results in positive GAIN of symptoms)
• dysfunction of parkin protein on chromosome 6 (results in negative LOSS of function)

Both of these symptoms lead to dysfunction of DA neurons.

Question 26

What is the term for specific abnormal circular structures in the cytoplasm of DA neurons whose presence is associated with dementia-like symptoms seen in Parkinson’s Disease?

Answer 26

Lewy Bodies.

Question 27

What is the purpose of Parkin? What happens to Parkin in Parkinson’s Disease?

Answer 27

Parkin is meant to destroy misfolded proteins in the cell. Since alpha-synuclein gets misfolded in the cell, naturally Parkin should prevent these damaged proteins from transforming others, but since Parkin is not functioning properly in Parkinson’s disease, it leads to a buildup of misfolded proteins in the cell, causing abnormal cell function, and thus the positive symptoms of Parkinson’s.

Question 28

What are the two forms of treatment for Parkinson’s Disease? Describe both.

Answer 28

(1) L.DOPA, deprenyl medication
- meant to increase dopamine, since there is a neurodegeneration of DA neurons

(2) Neurosurgery
- directly inhibiting the GPi through deep brain stimulation, since inhibiting the GPi activates motor movement

Question 29

What area does the thalamus regulate? What would happen if we were to inhibit the thalamus? What about if we were were activate it?

Using this information, describe what we would to do to the GPi to make movement easier in someone with Parkinson’s Disease?

Answer 29

Thalamus regulates the motor cortex.

Inhibit thalamus –> harder movement

Excite thalamus –> easier movement

The subthalamic nucleus strictly activates the GPi, and the GPi specifically inhibits the thalamus. We want to excite the thalamus to cause easier movement, so we would either

(1) inhibit the subthalamic nucleus so that it doesn’t activate the GPi to inhibit the thalamus, or;
(2) lesion the GPi so it doesn’t inhibit the thalamus

Question 30

Describe the pathway for making easy movement movement. What about for making movement harder?

Answer 30

Subthalamic nucleus activates the GPi, which inhibits the thalamus, which inhibits the motor cortex (making movement harder)

Question 31

What are two major hallmarks of Alzheimer’s Disease?

Answer 31

(1) Senile plagues
- caused by the proteopathy of Abeta protein

(2) Tauopathy
- the molecular structure of TAU gets changed causing TAU to form abnormal protein filaments

Question 32

Which areas of the brain go through degeneration in those with Huntington’s Disease?

Answer 32

Proteopathy of HTT occurs in the cortex, basal ganglia neurons (striatum), and GABA projections to motor areas

Question 33

What does proteopathy of the SOD1 protein result in for individuals with ALS?

Answer 33

The gene that SOD1 protein is on is responsible for increasing glutamate in the extracellular space, so if SOD1 misfolds and affects this gene, it may result in excitotoxicity of motor neurons.

Question 34

What is Multiple Sclerosis (MS) characterized by?

Answer 34

Demyelination of the autoimmune system, leading to motor dysregulation. Therefore, signals being sent in between neurons in the form of action potentials get interrupted.