Term
| the chief inhibitory neurotransmitter in CNS |
|
Definition
|
|
Term
| Which drug is good for simple partial seizures, complex partial seizures, generalized absence seizures, or generalized clonic, tonic, or tonic-clonic seizures. |
|
Definition
|
|
Term
Which of the following types of seizures can valproic acid treat?
simple partial seizures
complex partial seizures
generalized absence seizures
generalized clonic, tonic, or tonic-clonic seizures. |
|
Definition
| Valproic acid cna treat all types of seizures. |
|
|
Term
Which of the following types of seizures can carbamazepine treat?
simple partial seizures
complex partial seizures
generalized absence seizures
generalized clonic, tonic, or tonic-clonic seizures. |
|
Definition
| Carbamazepine can treat simple partial and complex partial siezures (but not generalized seizures). |
|
|
Term
Which of the following types of seizures can phenytoin treat?
simple partial seizures
complex partial seizures
generalized absence seizures
generalized clonic, tonic, or tonic-clonic seizures. |
|
Definition
| Phenytoin can treat simple partial seizures, complex partial seizures, and generalized clonic, tonic, or tonic-clonic seizures. It cannot treat absence seizures. |
|
|
Term
Which of the following types of seizures can ethosuccimide treat?
simple partial seizures
complex partial seizures
generalized absence seizures
generalized clonic, tonic, or tonic-clonic seizures. |
|
Definition
| Ethosuccimide only treats absence seizures. |
|
|
Term
| Which drug only treats absence seizures? |
|
Definition
|
|
Term
| Which drug only treats partial seizures (simple or complex)? |
|
Definition
|
|
Term
| Which drug treats all kinds of seizures EXCEPT absence seizures? |
|
Definition
|
|
Term
| What is the initial treatment for status epilepticus (a continuous epileptic seizure that lasts >30 minutes) |
|
Definition
|
|
Term
| a life-threatening cross-reactive hypersensitivity to all aromatic anti-epileptic drugs |
|
Definition
| Drug Reaction Eosinophilia & Systemic Symptoms (DRESS) syndrome |
|
|
Term
| Which 2 of our prototype drugs for epilepsy can people with DRESS or Stevens-Johnson NOT take? Which 2 can they take? |
|
Definition
People with DRESS or Stevens-Johnson cannot take aromatic drugs (phenytoin or carbamazepine).
They can take non-aromatic drugs (valproic acid for any kind of seizure, ethosuccimide for absence seizures) |
|
|
Term
| What virus causes 85-95% of all cases of acute aseptic meningitis? |
|
Definition
| enteroviruses (specifically picornaviridae) |
|
|
Term
| Describe the genome, capsid, & envelope of picornaviridae. |
|
Definition
(+)ss RNA genome
small icosahedral capsid
naked |
|
|
Term
| What family of viruses is the second most common cause of acute aseptic meningitis? |
|
Definition
| arboviruses (ex., West Nile) |
|
|
Term
| How are enteroviruses such as the picornaviridae identified as the cause of a case of meningitis? |
|
Definition
reverse transcription PCR on the CSF
(polymerase chain reaction on the cerebrospinal fluid) |
|
|
Term
| Who is particularly at risk for acute aseptic meningitis from enteroviruses such as the picornaviridae? |
|
Definition
| children under a year old |
|
|
Term
| Describe the genome, capsid, & envelope of arboviruses (such as West Nile)? |
|
Definition
(+)ss RNA
icosahedral capsid
enveloped |
|
|
Term
| Describe the genome, capsid, & envelope of herpes viruses (ex., HSV1, HSV2, CMV, Epstein-Barr, Varicella-Zoster). |
|
Definition
dsDNA
icosadeltahedral capsid
enveloped |
|
|
Term
| Describe the genome, capsid, & envelope of the mumps virus (paramyxoviridae). |
|
Definition
(-)ss RNA
helical capside
pleomorphic envelope |
|
|
Term
| Describe the genome, capsid, & envelope of the Lymphocytic Choriomeningitis Virus (Arenavirus family). |
|
Definition
(-)ss RNA, segmented
beaded capsid
pleomorphic envelope |
|
|
Term
| How are arboviruses such as West Nile Virus identified as the cause of a case of meningitis? |
|
Definition
reverse transcription PCR on the CSF
(polymerase chain reaction) |
|
|
Term
| How are herpes viruses such as HSV1, HSV2, Cytomegalovirus, Epstein-Barr, & Varicella-Zoster identified as the cause of a case of meningitis? |
|
Definition
PCR on the CSF
(polymerase chain reaction) |
|
|
Term
| How is mumps (a paramyxovirus) identified as the cause of a case of meningitis? |
|
Definition
| detection of mumps-specific IgM indicates an active infection |
|
|
Term
| How Lymphocytic Choriomeningitis Virus (in the Arenavirus family) identified as the cause of a case of meningitis? |
|
Definition
reverse transcription PCR on the CSF
(must be done in a BSL-3 lab) |
|
|
Term
| Who is particularly at risk of acute aseptic meningitis from arboviruses such as West Nile Virus? |
|
Definition
people who are exposed to arthropod vectors in endemic regions (...which is pretty much everywhere)
people >60 years old |
|
|
Term
| Who is particularly at risk of acute aseptic meningitis from herpes virus? |
|
Definition
people with an uncontrolled HSV2 genital infection
neonates
people with immunodeficiencies |
|
|
Term
| Who is particularly at risk of acute aseptic meningitis from mumps? |
|
Definition
| people who are not immunized against mumps |
|
|
Term
| Who is particularly at risk of acute aseptic meningitis from Lymphatic Choriomeningitis (in the Arenavirus family)? |
|
Definition
| people in contact with rodents (ex., people with pet hamsters) |
|
|
Term
| What family is Lymphatic Choriomeningitis in? |
|
Definition
| arenavirus (Latin, "sand" + virus--because the viruses pick up host ribosomes in their capsids, which look like grains of sand) |
|
|
Term
| What is the most common etiology of bacterial meningitis in patients age 16 years and older? |
|
Definition
|
|
Term
|
Definition
infection of parenchyma of brain itself
Parenchyma—the functional part of an organ
Stroma—the structural part of an organ (made of connective tissue) |
|
|
Term
| How do you distinguish encephalitis from meningitis? |
|
Definition
decreased mental status early in the course of the disease
minimal signs of meningeal irritation (headache, stiff neck, etc.) |
|
|
Term
| What symptom of meningitis is related to the eyes? |
|
Definition
|
|
Term
| What is the meningitis triad? |
|
Definition
|
|
Term
Fever
Headache
Photophobia
Irritability
Clouding of consciousness
Stiff neck
Vomiting |
|
Definition
|
|
Term
|
Definition
| inflammation of the brain |
|
|
Term
|
Definition
| collection of pus surrounded by well-vascularized capsule due to infection in brain tissue |
|
|
Term
| What more serious condition can cerebritis (inflammation of the brain) lead to? |
|
Definition
brain abscess
(brain abscess starts as cerebritis) |
|
|
Term
| What is the most common symptom of brain abscess? |
|
Definition
|
|
Term
| Brain abscess often begins as a primary infection in the _____ or _____ that spreads to the brain |
|
Definition
|
|
Term
| Acute pyogenic meningitis is typically caused by what kind of microbe? |
|
Definition
|
|
Term
| Acute aseptic meningitis is typically caused by what kind of microbe? |
|
Definition
|
|
Term
| Chronic meningitis is typically caused by what ____________ or ______________ bacteria or ______________ |
|
Definition
tuberculosis or spirochetal
cryptococcal (fungus) |
|
|
Term
| Features of CSF in acute septic meningitis |
|
Definition
usually cloudy b/c high WBC count
>1k WBC/mm3 (very high)
Neutrophils predominate
Increased protein levels (dead bacteria raise protein levels)
Decreased glucose (bacteria are eating glucose) |
|
|
Term
| When do neutrophils typically predominate a high WBC count? |
|
Definition
bacterial infection
early viral infection |
|
|
Term
| Features of CSF in acute aseptic meningitis |
|
Definition
Usually clear b/c lower WBC count
~100-500 WBC/mm3 (moderately high)
Except for very early in course, predominant cell type is mononuclear
Glucose levels may be normal or decreased |
|
|
Term
| Is viral or bacterial meningitis more severe? |
|
Definition
|
|
Term
| A small, naked icosahedral capsid (+)ssRNA virus that causes 85-95% of all asetpic meningitis |
|
Definition
| enteroviruses (picornaviridae) |
|
|
Term
| Who is most at risk for meningitis due to enteroviruses? |
|
Definition
|
|
Term
| Early in the life cycle of the Herpes virus are 2 transcription/translation events Describe them. |
|
Definition
First, transcribe Alpha mRNA—
proteins bind to DNA of virus & activate additional genes of virus
Makes DNA accessible for DNA replication
Then, transcribe Beta mRNA—
production of a viral DNA polymerase
production of more proteins that help to replicate viral DNA |
|
|
Term
| How does Herepes virus genome replicate? |
|
Definition
| rolling circle replication |
|
|
Term
| Where does the herpes virus get its envelope? |
|
Definition
| picks it up from the nuclear membrane as it leaves the nucleus (virus is replicated & capsid created in the nucleus) |
|
|
Term
| Herpes viruses can't transcribe _______ RNA unless it's replicating |
|
Definition
|
|
Term
| Why does herpes become latent in neurons? |
|
Definition
| Neurons don't have all the proteins that herpes needs to replicate, so instead of completing its life cycle and lysing from the cell, it becomes dormant. |
|
|
Term
| If you get a cold sore on your lip, where is the herpes virus living? |
|
Definition
|
|
Term
| Aseptic meningitis due to enterovirus infection usually occurs in what seasons? |
|
Definition
| Usually in early summer & fall |
|
|
Term
| What is the typical outcome of aseptic meningitis due to enterovirus? |
|
Definition
| Usually good outcome—recover in 1 week without any problems |
|
|
Term
| What virus causes West Nile? |
|
Definition
|
|
Term
| Streptococcus pneumoniae is ________-hemolytic |
|
Definition
| alpha (appears green on blood agar) |
|
|
Term
| Often borne by soft, refrigerated foods like lunch meat & soft cheeses |
|
Definition
|
|
Term
| Who should particularly avoid Listeria monocytogenes? |
|
Definition
| pregnant women--fetus often dies |
|
|
Term
| Listeria monocytogenes is particularly able to withstand ___________. |
|
Definition
cold (that's why it grows in refrigerated foods)
It's tolerant at 1C to 45C |
|
|
Term
| Neurulation starts in the _____-week-old embryo |
|
Definition
|
|
Term
| What 3 layers exist in the embryo after gastrulation? |
|
Definition
|
|
Term
| What layer of the gastrula does the notochord develop from? |
|
Definition
|
|
Term
| In the 3-week-old embryo, the mesoderm develops a notochord, which sends out ______ to affect cells around it |
|
Definition
|
|
Term
| The notochord expands to become the ______________________, which folds to become the _____________, and zips up to form the _______________ |
|
Definition
neural plate
neural fold
neural tube |
|
|
Term
| When looking at an embryo with a neural fold, which end is the end that looks like a butterfly? |
|
Definition
|
|
Term
| Near the crest of the neural groove are ___________ cells, which will develop into ____________ cells |
|
Definition
neural crest
neuroepithelial cells |
|
|
Term
| How do neural crest cells spread throughout the body? |
|
Definition
| they crawl away from the crest of the neural fold using ameboid-like locomotion |
|
|
Term
What do these cells arise from?
Schwann cells
Glial cells
Dorsal root ganglia
Sympathetic chain ganglia
Most of the cells in the brain (Neurons, Glioblasts) |
|
Definition
neural crest cells
(also correct, neuroepithelial cells, which descend from neural crest cells) |
|
|
Term
| What does the neural tube become? |
|
Definition
|
|
Term
Does gray matter or white matter normally line the ventricular system?
What could cause the wrong one lines the ventricular system? |
|
Definition
white matter
faulty migration of neural crest/neuroepithelial cells |
|
|
Term
| In the developing vertebrate embryo, _________ are masses of mesoderm distributed along the two sides of the neural tube and that will eventually become dermis (dermatome), skeletal muscle (myotome), and vertebrae (sclerotome). |
|
Definition
|
|
Term
| spina bifida and anencephaly arise from problems with |
|
Definition
|
|
Term
|
Definition
| the opening off the neural fold |
|
|
Term
| When should you take folic acid for it to be most effective at preventing neuropore closure defects? |
|
Definition
|
|
Term
| What can high alpha-fetoprotein (AFP) in amniotic fluid indicate? |
|
Definition
|
|
Term
|
Definition
| a neuropore closure defect in which the skull didn’t completely close (but, unlike anencephaly, it's mostly closed) |
|
|
Term
|
Definition
| a form of cranium bifida in which part of the brain bulges out in a sac when the skull doesn't completely close |
|
|
Term
|
Definition
| a form of cranium bifida in which part of the brain, including part of the ventricles, bulges out in a sac when the skull doesn't completely close |
|
|
Term
|
Definition
| a form of cranium bifida in which the part of the meninges around the brain bulges out in a sac when the skull doesn't completely close |
|
|
Term
| non-communicating hydrocephalus |
|
Definition
| caused by impaired cerebrospinal fluid resorption in the absence of any CSF-flow obstruction between the ventricles and subarachnoid space |
|
|
Term
| How do you treat hydrocephaly? |
|
Definition
| Surgically place a shunt or ventricular catheter—let CSF flow form cerebral ventricles to the peritoneal cavity |
|
|
Term
|
Definition
| rare birth defect, which occurs perinatally, consisting of a cyst or cavity in the cerebral hemisphere lined with white matter |
|
|
Term
|
Definition
| like an extreme form of porencephaly; both cerebral hemispheres are absent & replaced by sacs filled with CSF |
|
|
Term
|
Definition
| abnormal slits/clefts in cerebral hemispheres, lined by gray matter |
|
|
Term
| What is the main difference between a porencephaly & a schizencephaly? |
|
Definition
a porencephaly is lined with white matter
a schizencephaly is lined with gray matter |
|
|
Term
|
Definition
the prosencephalon (forebrain of embryo) fails to split properly
Most severe—cyclops, with nose above eye(s)
Can have 2 eyes, but 1 nostril
Or eyes are just a little closer together
Oven spontaneous abortion |
|
|
Term
Alobar holoprosencephaly
Semi-lobar holoprosencephaly
Lobar holoprosencephaly |
|
Definition
Alobar holoprosencephaly--prosencephalon completely fails to split, leading to one cerebral lobe (usually severe birth defect; may look like a cyclops & have nostril above eye)
Semi-lobar holoprosencephaly--prosencephalon fails to split completely; may have 2 eyes but just 1 nostril
Lobar holoprosencephaly--prosencephalon splits but, cerebral lobs are closer together than normal; may appear normal but eyes are a little closer together than usual |
|
|
Term
| head is 2 standard deviations smaller than average for age & sex; face is normal-sized |
|
Definition
|
|
Term
| birth defect which consists of herniation of cerebellar tonsils thru foramen magnum |
|
Definition
| Arnold-Chiari malformation |
|
|
Term
|
Definition
| a condition in which a body orifice or passage in the body is abnormally closed or absent. |
|
|
Term
| Congenital atresia (closure) of foramina of Luschka or Magendia leads to obstructive hydrocephalus, dilation of fourth ventricle, agenesis of cerebellar vermis (just CSF) |
|
Definition
|
|
Term
| a rare neurological disorder caused by tissue atachments that limit the movement of the spinal cord within the spinal column, which leads to abnormal stretching of spinal cord |
|
Definition
|
|
Term
| malignant tumor of CNS that originates in astrocytes |
|
Definition
|
|
Term
| If there are multiple tumors in the brain, what can you most likely say about the origin of the tumor? |
|
Definition
| it probably originated elsewhere. Tumors (esp. Glial tumors) that originate in brain tend to stay in one place—not split off & form other tumors |
|
|
Term
| malignant tumors that arise form oligodendroctyes |
|
Definition
|
|
Term
|
Definition
|
|
Term
| In oligodendrogliomas, co-deletions of chromosomal arms 1p & 19q correlate with: |
|
Definition
|
|
Term
| Why don't you see grade I oligodendrogliomas? |
|
Definition
|
|
Term
| How many grades are there of brain tumors, and which is most severe |
|
Definition
|
|
Term
| tumor of unpredictable malignant potential (different levels of aggressiveness) that arises from the ependyma |
|
Definition
|
|
Term
| papillary, myxoid, and subependymoma are types of _______ tumor |
|
Definition
|
|
Term
| the thin epithtelial membrane lining the ventricular system of the brain and the spinal cord. Ependyma is one of the four types of neuroglia in the central nervous system. It is involved in the production of cerebrospinal fluid (CSF). |
|
Definition
|
|
Term
| What kind of brain cancer forms gland-like structures called rosettes? |
|
Definition
|
|
Term
| benign, slow-growing tumor attached to the dura mater |
|
Definition
|
|
Term
| What kind of brain cancer shows swirls of cells? |
|
Definition
|
|
Term
| most common type of tumor in the brain |
|
Definition
| metastatic carcinoma (arises from epithelial cells elsewhere in body; spreads to brain) |
|
|
Term
| benign sheath tumor composed of only of Schwann cells |
|
Definition
|
|
Term
| What is the difference between a Schwannoma & a neurofibroma? |
|
Definition
a Schwannoma consists of ONLY Schwann cells
a neurofibroma is a Schwann cell tumor that also encompasses other types of cells within the tumor |
|
|
Term
| type of tumor with spindle-shaped cells and alternating areas of compact cells (antony A) & less dense areas (antony B) |
|
Definition
|
|
Term
| How does a Schwannoma cause brain tumors? |
|
Definition
|
|
Term
| well-circumscribed tumor consisting of Schwann cells, perineural like cells, & fibroblasts in a fibrous or myxoid (mucous-like) background |
|
Definition
|
|
Term
| What is the chance that a neurofibroma will become malignant? |
|
Definition
|
|
Term
| Neurofibromas are usually found in people with what condition? |
|
Definition
|
|
Term
café au lait spots
freckling in axillae or inguinal (groin) regions
multiple neurofibromas
may get a plexiform neurofibroma (aka solitary neurofibroma)—a single neurofibroma arising from nerves in the skin or more internal nerve bundles
Lisch nodultes (eye hamartomas) |
|
Definition
|
|
Term
| a single neurofibroma arising from nerves in the skin or more internal nerve bundles; can be very large; can become malignant |
|
Definition
| plexiform neurofibroma (aka solitary neurofibroma)— |
|
|
Term
originate from Schwann cells surrounding nerves in the skin
typically occur in groups sprinkled over the skin
look like lots of bumps on or under the skin; grow throughout adulthood but never get very large
no evidence of malignant transformation |
|
Definition
| Dermal (cutaneous) neurofibroma |
|
|
Term
| Only people with neurofibromatosis type I get _____________ neurofibromas |
|
Definition
|
|
Term
| malignant peripheral nerve sheath tumor (MPNST) |
|
Definition
| the malignant version of a Schwannoma or neurofibroma |
|
|
Term
| How does a malignant peripheral nerve sheath tumor (MPNST) clinically present differently than a Schwannoma or neurofibroma? |
|
Definition
|
|
Term
|
Definition
| a benign mass of tissue elements that are normally found at that site, but which are growing in a disorganized mass. • Unlike a benign neoplasm, it grows at the same rate as the surrounding tissues. |
|
|
Term
| What can you do for neurofibromatosis type I? |
|
Definition
No cure
Followed by a specialist for symptomatic treatment & to manage complications
<8-12% of people with neurofibromatosis develop cancerous growths |
|
|
Term
| CNS cells with a fried egg appearance |
|
Definition
| Oligodendrocytes (they form the myelin sheath in the CNS) |
|
|
Term
| _________ cells give the brain structure |
|
Definition
|
|
Term
| __________ help diffuse trauma to avoid hematoma of brain |
|
Definition
|
|
Term
| headache, malaise, mental confusion, & vomiting developing 2-6 months after respiratory infection |
|
Definition
| chronic meningitis due to mycobacterium tuberculosis |
|
|
Term
| While rare in the US, this is the most common cause of chronic meningitis world-wide |
|
Definition
| mycobacterium tuberculosis |
|
|
Term
| How do you find out if a microbe is cryptococcus neoformans with a light microscope? |
|
Definition
To see, can inject with India ink, which surrounds but does not penetrate the capsule
You will see pale spots (the capsule) 5X bigger than the yeast itself. |
|
|
Term
| What do cryptococcus neoformans colonies look like |
|
Definition
yellow
mucoid (b/c of the capsule) |
|
|
Term
| Most common cause of fungal meningitis. |
|
Definition
Cryptococcus neoformans
(note: fungus only causes chronic meningitis) |
|
|
Term
| A person develops chronic meningitis after mucking out a bird coop and inhaling the aerosolized poop. What 2 fungi are most likely to be the culprits |
|
Definition
cryptococci neoformans (more common)
Histoplasma capsulatum |
|
|
Term
| While Cryptococcus neoformans and Histoplasma capsulatum both grow in bird poop, which one also grows in bat poop? |
|
Definition
|
|
Term
| What form does Histoplasma capsulatum take in the body? What form does it take in the open environment? |
|
Definition
in the body (where it's warmer), Histoplasma capsulatum is a yeast
in the open environment, it grows hyphae with aerosolizable spores |
|
|
Term
| Describe the clinical features of histoplasmosis. |
|
Definition
Usually, mild respiratory infection
Chronic disseminated histoplasma capsulatum is characterized by
• Weight loss
• Fatigue
• With or without fever |
|
|
Term
| While microscopy and the India ink test are important for diagnosing Cryptococcus neoformans, what other test can you use to diagnose? |
|
Definition
| latex agglutination test to test for Cryptococcus neoformans capsule antigen |
|
|
Term
| What are 2 ways to diagnose Histoplasma capsulatum. |
|
Definition
Diagnosis by isolation & culture (takes 4-6 weeks)
Or by antigen detection in blood or urine (take a few days) |
|
|
Term
| What fungus causes Valley fever or San Joaquin Fever? |
|
Definition
|
|
Term
| Primary clinical features of Coccidioides immitis infection |
|
Definition
| Valley fever or San Joaquin fever: respiratory infection (bad cough) that usually resolves without therapy & confers a strong, specific immunity to re-infection |
|
|
Term
| Do we culture Coccidioides immitis? Why or why not? |
|
Definition
| We don’t culture it b/c Valley Fever (aka San Joaquin fever) is so infectious |
|
|
Term
| What fungus causes an illness often found in southwest, especially south-central Arizona & a valley of California |
|
Definition
Coccidioides immitis
(causes Valley fever or San Joaquin Fever) |
|
|
Term
| What is the clinical presentation of meningovascular neurosyphilis, a type of neurosyphilis? |
|
Definition
| young person dies of a stroke |
|
|
Term
| What are the clinical features of paretic neurosyphilis? |
|
Definition
| delusions, mood alterations, progressive muscular weakness, paralysis |
|
|
Term
| Neurosyphilis is a type of _________ (primary/secondary/tertiary) syphilis, that occurs __________ after innoculation |
|
Definition
|
|
Term
| How are the clinical features of syphilitic meningitis and lyme borreliosis different? |
|
Definition
Syphilitic meningitis doesn't cause cranial nerve palsies
Lyme borreliosis meningitis does (most often CN VII, facial, but also others) |
|
|
Term
Explain the following mnemonic:
shoot the BB at the target |
|
Definition
| Borrelia burgdorferi (BB) causes lyme disease (target-shaped rash) |
|
|
Term
| What nerve does Lyme borreliosis meningitis most commonly cause palsies in? |
|
Definition
|
|
Term
| What kind of microbe is Acanthamoeba? |
|
Definition
|
|
Term
| What kind of microbe is Naegleria? |
|
Definition
|
|
Term
| Differentiate between meningitis caused by Acanthamoeba as compared to Naegleria. |
|
Definition
Acanthamoeba--Meningitis evolves over a few weeks (more chronic)
Naegleria--Meningitis course is very rapid—can die in a few days |
|
|
Term
Explain the mnemonic:
You CAN neglect aCANthomoeba, but don't neglect Naegleria? |
|
Definition
Acanthomoeba & Naegleria are both amoebas that (rarely) cause meningitis in humans
Meningitis dues to acanthameoba develops gradually, but meningitis due to Naegleria develops rapidly & can kill you in a few days. |
|
|
Term
| How are you most likely to get acanthomoeba or naegleria infections? |
|
Definition
by swimming in contaminated water
acanthomeoba & naegleria are both amoebas |
|
|
Term
| Most common parasitic infection of CNS. A tapeworm that lives in contaminated pork in endemic regions (ex., Mexico) |
|
Definition
|
|
Term
Explain the mnemonic:
Tanya gets sick when she eats soul food. |
|
Definition
| Tania solium is a tapeworm that lives in infected pork. |
|
|
Term
| If soldiers are very stressed & sleep deprived for several days in a row, 1/200 will have a ___________ |
|
Definition
|
|
Term
| discrete clinical event that is directly related to abnormal hyper-synchronous discharge of cortical neuron |
|
Definition
|
|
Term
| for generalized tonic-clonic seizures, the prodrome may include the following symptoms, hours or days before the seizure: |
|
Definition
mood changes
sleep disturbances
lightheadedness
anxiety
irritability
difficulty concentrating |
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Term
| refers to a physiologic state or event such as a seizure, stroke or headache (as opposed to prodromal, an early symptom or set of symptoms that might indicate the start of a disease before specific symptoms occur) |
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Definition
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Term
| What happens in the post-ictal state of a seizure? |
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Definition
| typically 5-30 minutes of drowsiness, confusion, nausea, hypertension, headache or migraine and other disorienting symptoms |
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Term
| What is sometimes seen in the inter-ictal state of an epileptic patient on EEGs? |
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Definition
spikes
(inter-ictal means "between physiologic events such as a seizure, stroke or headache"; here it refers to the time between epileptic seizures) |
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Term
| Should you empirically treat epilepsy? |
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Definition
| no; anti-epileptic medicines have serious side effects |
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Term
| A man has seizures that occur asssociated with specific events, last for hours, and look different every time that occur? What is the most likely cause? |
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Definition
psychogenic
"real" seizures are sporadic, spontaneous, self-limited, stereotyped |
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Term
| What is a simple focal seizure? |
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Definition
occurs in part of the body
preserved responsiveness, awareness, & recall |
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Term
| What is a complex focal seizure? |
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Definition
occurs in part of the body
responsiveness, awareness, & recall are not preserved |
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Term
| Why are complex focal seizures dangerous? |
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Definition
the person may harm themselves or others
they are in a "primitive" state & may physically lash out if opposed |
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Term
| What is a secondarily generalized seizure? |
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Definition
| starts as a partial seizure, then spreads to the rest of the brain to a generalized tonic-clonic seizure |
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Term
| simple partial seizure with strange feelings (déjà vu, dizziness, anxiety) that may precede a tonic-clonic seizure |
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Definition
aura
(prodrome occurs before aura) |
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Term
| Describe the 2 main phases of a tonic-clonic seizure? |
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Definition
Tonic—skeletal muscles become tense (extremities pull towards body or push away), person loses consciousness, person falls, typically only lasts a few seconds, person may moan or vocalize due to air forcefully expelling form lungs
Clonic—muscles contract & relax rapidly
(etymologically related to clonus, a series of involuntary muscular contractions due to sudden stretching of the muscle) |
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Term
| Tonic generalized seizure |
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Definition
suddenly propelled to ground by whole-body muscle contractions
may be wheelchair-bound because of abrupt, unpredictable falls |
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Term
| Atonic generalized seizure |
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Definition
suddenly fall like a sack of potatoes
may be wheelchair-bound because of abrupt, unpredictable falls |
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Term
| a very brief seizure with no prodrome or recovery period. Posture is maintained--person seizing just appears "out of it" |
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Definition
| Absence (ab-SAHNS) seizure |
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Term
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Definition
| a generalized seizure characterized by brief, shock-like jerks |
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Term
| Biggest causes of morbidity related to seizure are _________ |
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Definition
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Term
What can the following cause?
Abnormal combinations & distributions of ion channels
Abnormal connections—too many excitatory connections or too few inhibitory connections
Neuronal metabolism—how cells process things
Buffer cells
Abnormal responses to normal physiological fluctuations (ex., hormonal states) |
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Definition
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Term
| 20% of women with epilepsy are well-controlled except: |
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Definition
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Term
| What 4 basic clinical features that distinguish epileptic seizures due to epilepsy from other types of spells and attacks? |
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Definition
epileptic seizures are
sporadic--occur at random intervals
spontaneous--not brought on by anything in particular
Self-limited, brief—a few minutes
Stereotyped—looks similar every time |
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Term
| Is gray or white matter normally seen around the ventricles? |
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Definition
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Term
| Gray matter in a place that normally has white matter can cause ________ |
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Definition
|
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Term
| very high or very low blood glucose can cause what kind of event? |
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Definition
epileptic seizures
(note: identifiable, acute, specific, & sufficient circumstances can cause epileptic seizures in people without epilepsy) |
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Term
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Definition
| an EEG in which the voltage of a bunch of “active” electrodes is measured with reference to a single reference electrode |
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Term
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Definition
| an EEG in which voltage difference is measured between a pair of electrodes |
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Term
| All EEGs should include a minimum of three montages: |
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Definition
a longitudinal bipolar montage
a transverse bipolar montage
a referential montage |
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Term
| If the FIRST spike in an EEG event goes up, but the BIGGEST spike goes down, is it a positive or negative spike? |
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Definition
negative
(first spike is what counts; trace up means negative, trace down means positive) |
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Term
| In an EEG, odd-numbered electrodes are on ____ side of head; even numbered on the __________ |
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Definition
odd on the left
even on the right |
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Term
What do the following abbreviations mean with reference to an EEG montage?
F, T, P, C, O Z, Fz, Cz, Pz |
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Definition
F = frontal
T = temporal
P = parietal
C = central
O = occipital
Z = midline
Fz = frontal, midline
Cz = central, midline
Pz = parietal, midline |
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Term
| ___________ montages are usually arranged in longitudinal or transverse chains, left over right. |
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Definition
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Term
|
Definition
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Term
|
Definition
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Term
|
Definition
|
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Term
|
Definition
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Term
| An EEG typically lasts _______ and preferably includes periods of what 5 states? |
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Definition
at least 30 minutes
wakefulness
drowsiness
sleep
photic stimulation
hyperventilation |
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Term
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Definition
| any kind of visual stimulation used to trigger an anomalous event (ex., flashing lights to trigger a seizure) |
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Term
| EEGs pick up a signal created by the _____________, influenced by ________ structures (mostly the __________) and sent outwards via _______________ cells, which produce IPSPs and EPSPs on the surface of the brain. |
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Definition
cereberal cortex
subcortical
thalamus
cortical pyramidal cells |
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Term
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Definition
| large cortical neurons that are oriented perpendicular to the outer surface of the cortex (that is, one end is at the surface of the cortex & the rest goes straight down into the cortex) |
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Term
| The electrical signal that reaches the EEG is modified by electrical "sources" (_________) and "sinks" (___________) |
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Definition
EPSPs (excitatory post-synaptic potentials)
IPSPs (inhibitory post-synaptic potentials) |
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Term
| Cortical pyramidal cells produce a signal which is particularly useful in getting an EEG because they have a relatively long duration of post-synaptic potential, which allows lots of ___________ |
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Definition
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Term
| Action potentials are so fleeting & disorganized that they don’t contribute much to EEGs. Instead, EEGs measure ________________, which are longer-lasting & better organized |
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Definition
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Term
| Why is the signal picked up by an EEG better for seeing underlying global or regional electrocerebral effects than for pinpointing an effect? |
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Definition
| because they pick up signal from a large area of cortex surface |
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Term
| Why are post-synaptic potentials of more use to EEGs than action potentials? |
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Definition
| they last longer & are better organized (APs are very brief & disorganized) |
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Term
| For patients undergoing brain surgery, you can use a ____________to get better localization than the standard EEG |
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Definition
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Term
| What are 3 important features of a normal EEG for an adult? |
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Definition
Background frequency appropriate for wakefulness
Reactive to eye opening/closing
Normal EEG changes with transitions of arousal state |
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Term
Alpha rhythm is characterized by:
Alpha frequency range: 8 – 13 Hz
____________ distribution of electrical activity
Standard wave more noticeable when _______________
Changes according to ___________ state |
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Definition
occipital
eyes closed (b/c occipital lobe isn't getting information from eyes that covers up/interferes with standard wave)
alertness (drowsy, full awake, asleep, etc.) |
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Term
| Normal brain patterns during wakefullness are usually a combination of _______, ________, and __________ activity, but not ___________ |
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Definition
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Term
Beta Activity
A low-amplitude feature
Frequency range: >13 Hz (typically 15-25 Hz)
What is the distribution?
Is it affected by eye opening/closing?
Is it affected by alertness state? |
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Definition
widely distributed over the cortex, but especially anteriorly
not affected by eye opening/closing
Changes a little bit according to alertness state |
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Term
Theta activity
Frequency range: 4 – 8 Hz
Low to moderate amplitude
What is the distribution?
When does it occur during wakefulness? |
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Definition
widely distributed
it is sparsely intermixed with the other activity patterns |
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Term
| When is delta activity usually seen? |
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Definition
during Hyperventilation
with onset of drowsiness
with arousal from drowsiness
it's a transient activity pattern that doesn't normally stick around for long |
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Term
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Definition
| inter-ictal focal or generalized spikes or sharp waves that stand out from & disrupt the EEG background activity & are not related to recording artifacts or recognizable EEG variants |
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Term
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Definition
|
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Term
| Mutation rate of mtDNA is about 10 X that of nuclear DNA because: |
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Definition
there is limited DNA repair mechanism in the matrix of mitochondria
the level of free radical production during oxidative phosphorylation is high and easily damages mtDNA. |
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Term
| Mitochondrial DNA (mtDNA) characteristics |
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Definition
Double-stranded circular molecule
No histones
Up to 10 DNA molecules per mitochondrion
Encodes 37 genes |
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Term
| All organs are affected by mitochondrial disease, but 3 have particularly high ATP needs |
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Definition
Neurons
Heart muscle
Skeletal muscles |
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Term
| homoplasmy (of mitochondria) |
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Definition
| when a mutation affects all of the mitochondria in a cell |
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Term
| heteroplasmy (of mitochondria) |
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Definition
| when a mutation affects only some of the mitochondria in a cell |
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Term
Progressive bilateral, painless visual
failure that develops in young adult.
Males are more likely affected for
unknown reasons. Selective
degeneration of the retinal ganglion cell
layer and optic nerve. Other features
may include cardiac arrhythmias,
postural tremor and movement
disorders. Mitochondrial Inheritence. |
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Definition
Leber Hereditary Optic
Neuropathy (LHON) |
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Term
Myoclonus (muscle twitching), seizures,
cerebellar ataxia, dementia, abnormal
mitochondria in skeletal muscle that
impart an irregular shape and bloddy red
staining of the muscle cells. Some
mitochondria contain parking lot
inclusions. Mitochondrial inheritence |
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Definition
Myoclonic Epilepsy Ragged‐Red Fibers
(MERRF) |
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Term
Mitochondrial myopathy evidenced by
lactic acidosis, encephalopathy with
seizures/dementia, stroke like episodes. Mitochondrial inheritence. |
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Definition
| Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis and Stroke-like Episodes syndrome (MELAS) |
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Term
Chronic progessive external
ophthalmoplegia (paralysis of the muscle
controlling the eyes),pigmentary
degeneration of the retina, hearing loss, vestibular dysfunction, cerebellar ataxia and onset around 20 years of age. Mitochondrial inheritence. |
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Definition
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|
Term
Disease of early childhood, lactic
acidosis, arrest of psychomotor
development, feeding problems,
seizures, extraoccular palsies and
weakness with hypotonia. Death within
1 to 2 years. Mitochondrial inheritence. |
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Definition
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Term
| How could heteroplasmy of mitochondria lead to incomplete penetrance, variable expression, and pleiotropy |
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Definition
a cell with a mixture of mutated and non-mutated mitochondria could, by chance, sort populations with very different proportions of mutated-to-wild-type into its daughter cells
leads to
incomplete penetrance—not all people with a mutation have a disease (if only a small portion of their mitochondria are mutated)
variable expression—different people with the same mutation may have different severity of disease (because the more severely affected person has more mutated mitochondria, or more mutated mitochondria in critical organs)
pleiotropy—when one gene affects multiple traits (because mutated mitochondria could be sorted to different parts of the body) |
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Term
|
Definition
absence seizures
Doesn’t seem to work for any other kind of seizures |
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Term
| Ethosuxamide prevents absence seizures by by blocking _____ channels in the ________ |
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Definition
calcium
thalamus
(like Valproic acid, but that works on a wider variety of seizures) |
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Term
| Valproic acid prevents a broad spectrum of seizures by blocking ____ channels in the ___________ |
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Definition
calcium
thalamus
(like Ethosuxamide, but that works on a wider variety of seizures) |
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Term
| What anti-epileptic drugs can treat simple partial seizures, complex partial seizures, generalized absence seizures, and generalized clonic, tonic, or tonic-clonic seizures? |
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Definition
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Term
| All anti-epileptic drugs work by reducing: |
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Definition
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Term
What side effects are a big concern for children on anti-epileptic drugs?
What about for adults? |
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Definition
learning disabilities
can impair learning & mental alertness (enough to make it unsafe to operate a machine) |
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Term
|
Definition
| life-threatening condition in which the brain is in a state of persistent seizure (>30 minutes) |
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Term
| The initial treatment for status epilepticus in adults and children. |
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Definition
|
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Term
| What 2 things do you give if you suspect chronic alcoholism or malnutrition as a source of seizures |
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Definition
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Term
|
Definition
|
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Term
| Benzodiazepene is an anti-epileptic drug that is also used during surgery: |
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Definition
|
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Term
|
Definition
| one of the most important enzymes involved in the metabolism of foreign substances in the body |
|
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Term
| a life-threatening cross-reactive hypersensitivity to all aromatic anti-epileptic drugs |
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Definition
| Drug Reaction Eosinophilia & Systemic Symptoms (DRESS) syndrome |
|
|
Term
target rashes on palms & soles
slight rubbing can separate skin layers, leading to open, painful areas |
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Definition
| Stevens-Johnson (Lyell’s syndrome) |
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