Term
| Which parts of the neuron has abundant RER and nissl bodies? |
|
Definition
| Dendrites and body; axons have abundant SER |
|
|
Term
| Which microtubule associated proteins are found in what specific parts of the neuron? |
|
Definition
| Dendrites- MAP2, Soma-MAP1,5, Axon-MAP1,3,5 |
|
|
Term
| Which part of the neuron is devoid of nissl bodies(RER equivalents) and unmyelinated and initiates action potentials? |
|
Definition
| Axon hillock or intial segment |
|
|
Term
| _____________ is a motorneuron disease eventually causing death from respiratory paralysis. |
|
Definition
| Amyotrophic lateral sclerosis (ALS) |
|
|
Term
| Loss of dopaminergic neurons in the substantia nigra results in which disease? |
|
Definition
|
|
Term
| What is the function of astrocytes and where are they found in grey and white matter? |
|
Definition
| They help maintain the BBB, maintain extracellular environment, coupled by gap junctions and respond to injury by becoming a reactive astocyte that are glassy pink and GFAP+; protoplasmic are found in gray matter, and fibrous are found in white |
|
|
Term
| What is the name of the cell that is the macrophage of the CNS, that is derived from blood monocytes, and become enlarged and motile when damage occurs? |
|
Definition
|
|
Term
| The _______ __________ is formed by the envagination of pia matter and ependymal cells in ventricular spaces |
|
Definition
|
|
Term
| What are satellite cells? |
|
Definition
| They are found in both sensory and autonomic ganglia, they are multipotent glial cells that support the neuron cell body yet do not contain myelin |
|
|
Term
| Differentiate epi/peri/endonuerium connective tissue that cover peripheral nerves. |
|
Definition
| Epi- dense irregular CT, peri- dense CT joined by tight junctions that isolate blood-nerve barrier, endo- loose CT with fixed macrophages, capillaries, and mast cells that surround Schwann cells |
|
|
Term
| True or False: sensory cells have different diameters but have uniform shape and receive synaptic contacts. |
|
Definition
| False, sensory cells receive no synaptic contacts |
|
|
Term
| True or False: autonomic postganglionic cells are multipolar cells, receive synaptic contact, and have cell bodies that are surrounded by satellite cells. |
|
Definition
|
|
Term
| What is the name of the cell that lines the cerbellar cortex, has numerous dendritic projections, and is involved in the refinement of motor activities? |
|
Definition
|
|
Term
| How are the thalamus and the cerebral cortex related? |
|
Definition
| The thalamus receives and processes specific types of incoming info then sends it to the cortex; damage to the thalamus does not occur in isolation and damage to specific regions of the thalamus and cortex reveals characteristic clinical motor and sensory signs |
|
|
Term
| Degeneration of the basal ganglia results in disorders like Huntington’s and Parkinson’s, what does this area of the brain do? |
|
Definition
| It is associated with motor control and motor planning |
|
|
Term
| The hippocampus, located deep in the temporal lobe, is responsible for what processes? |
|
Definition
| Learning and memory; degeneration leads to epilepsy or Alzheimer’s |
|
|
Term
| What is a SNARE complex and how does BOTOX affect them? |
|
Definition
| SNARE is a series of vesicle bound proteins that when bound to calcium (synaptotagmin) induces the vesicle to release its neurotransmitters by exocytosis; BOTOX works to cleave these proteins (synaptobrevin) thereby preventing neuro release |
|
|
Term
| The NMJ has a high safety factor, what does that mean? |
|
Definition
| It means its resting potential is far enough away from the depolarization limit to prevent spontaneous signal transmission; it also refers to the excess of neurotransmitters used to conduct signals across the synapse |
|
|
Term
| What role do Schwann cells play for axons in the PNS if they don’t myelinate them? |
|
Definition
| They support the axonal tissues |
|
|
Term
| True or False: decreasing diameter increases the speed of conduction in myelinated axons. |
|
Definition
| False, increasing diameter increases speed linearly in myelinated axons, and to the square root of diameter in unmyelinated |
|
|
Term
| What is the difference between CMAP and SNAP? |
|
Definition
| CMAP measures the activation of many muscle fibers through a synapse by taking the difference in latency; SNAP measures sensory nerve conduction without a synapse, have smaller voltage; both are useful for detecting defecits |
|
|
Term
| How does myelination increase AP? |
|
Definition
| It reduces membrane capacitance and lowers current leak laterally |
|
|
Term
| How does demyelination interrupt signaling? |
|
Definition
| Current is lost to charge the capacitance of the membrane through the few sodium channels that exist at nodes, so conduction is either slowed or stopped while the amplitude should remain the same. |
|
|
Term
| Describe the process of nerve injury and regeneration. |
|
Definition
| In the proximal cell the nissl bodies and RER disappear (chromolysis) or move to the periphery and the distal axon undergoes degeneration via enzymes; the proximal axonal stump starts a sprouting cone and distal schwann cells form tube, so if connection remade then function resumes, otherwise both atrophy over time |
|
|
Term
| What are the two types of cholinesterases and where are they located? |
|
Definition
| Ach-E is located in cholinergic synapses and erythrocytes; Psuedo-E occurs in the plasma, liver, and glia and it breaks down succinylcholine |
|
|
Term
| What is the difference between Lambert-Eaton Myasthenic syndrome and Mysthenia gravis? |
|
Definition
| LEMS is due Ab against presynaptic Ca channels, MG is due to Ab against postsynaptic nicotinic receptors at NMJ |
|
|
Term
| What are the 3 therapies for myasthenia gravis? |
|
Definition
| Immunotherapy with gamma globulin, plasmapheresis, thymectomy |
|
|
Term
| What is the dibucaine number used for? |
|
Definition
| To assess the effectiveness of a patients Pseudo-AchE, where 80 is normal and 20 is homozygous mutant |
|
|
Term
| What is the difference between GABA-A and GABA-B receptors? |
|
Definition
| A is a ligand gated Cl channel that hyperpolarizes membranes, B is a G-protein receptor that increases K conductance and inhibits cAMP |
|
|
Term
| How do you grade deep tendon reflexes? |
|
Definition
| Scale of 0 to 4 with 2 being normal, rated as follows - absent, minimal, normal, brisk, brisk with clonus |
|
|
Term
| What is the Babinski sign? |
|
Definition
| Normal response to stroking the bottom of foot is big toe flexion, damage to corticospinal pathways causes extension of the big toe |
|
|
Term
| ID whether each of these is a sign that a problem is located either peripherally or centrally - deep tendon reflexes decreased or normal, babinski sign present, muscle atrophy, muscle fatigue (MG), increased tone/spasticity, fasciculations, crossed finding, deep tendon reflexes increased, babinski absent? |
|
Definition
| P, C, P, P, C, P, C, C, P |
|
|
Term
| List the grades of muscle strength. |
|
Definition
| 0-no contraction, 1-trace contraction, 2-active w/o gravity, 3-active w/ gravity, 4-active with some resistance, 5-active with full resistance |
|
|
Term
| ID which type of nerve injury has the following “positive” effects - 1. fasciculations/cramps 2. paresthesias 3.dysesthesias/allodynia 4. increased sweating/hypertension |
|
Definition
| 1-motor, 2-sensory large fiber, 3-sensory small fiber, 4-autonomic nerves |
|
|
Term
| When looking at a nerve conduction study in polyneuropathy what difference will you notice in the waveforms in demyelinated nerves versus axonal degradation? |
|
Definition
| Demylination will show a slow conduction while the axonal will show low amplitude CMAP/SNAP |
|
|
Term
| When looking at EMG interference pattern in neuropathy what will you notice in a denervation or conduction block versus a reinnervation? |
|
Definition
| Conduction block will show reduced interference pattern whereas reinnervation will show motor unit potentials of increased amp and duration |
|
|
Term
| What is the name of the common demyelinating polyneuropathy that results in rapid paralysis, is post-infectious 60% of the time, and causes paresthesias and lost reflexes? |
|
Definition
|
|
Term
| What are the 6 D’s used to make an etiologic diagnosis for neuropathy? |
|
Definition
| Distribution, duration, deficits (involved fibers), disease pathology(axonal or demy), developmental, drug |
|
|
Term
| Axonopathy or Myelinopathy: majority are toxic/metabolic causes, CMAP 80% of normal or distal motor latency, legs>arms, EMG shows signs of denervation and reinnervation |
|
Definition
|
|
Term
| Axonopathy or Myelinopathy: hypertrophic nerves, arreflexia, motor>sensory, NCS shows slowed conduction velocity or distal motor latency prolonged, EMG shows reduced recruitment without much denervation |
|
Definition
|
|
Term
| When thinking of diseases causing deficits in predominantly motor fibers you think of what 3? |
|
Definition
| Guillain Barre, Lead Toxicity, or Charcot-Marie-Tooth (demy) |
|
|
Term
| When thinking of diseases causing deficits in sensory/proprio fibers you think of what 2? |
|
Definition
|
|
Term
| When thinking of diseases causing deficits in autonomic small fibers you think of what 3? |
|
Definition
| Diabetes, amyloid, drugs like vincristine/DDL/DDC |
|
|
Term
| What is the difference between primary and secondary demyelination? |
|
Definition
| Primary-degeneration of myelin in the presence of intact axon, secondary- degeneration as a result of degeneration of the axon |
|
|
Term
| Differentiate retrograde degeneration versus trans-synaptic degeneration. |
|
Definition
| Retro- neuron cell bodies atrophy if there is progressive injury to the distal axon, trans-syn- neuron atrophies if major synaptic input is lost due to infarct/trauma/injury |
|
|
Term
|
Definition
| Neurons become overstim’d due to excessive glutamate on iontropic cell receptors causing cell death |
|
|
Term
| What is the most common primary tumor within the CNS? |
|
Definition
|
|
Term
| Which responds to injury in the brain - microglia or astrocytes? |
|
Definition
| Both, astocytes are more slow and stain GFAP+, while microglia are quicker to respond and are GFAP-, CD68+ |
|
|
Term
| In the ventral horn of the spinal chord alpha motor neuron cell bodies innervate striated muscle, what does the gamma motor neuron innervate? |
|
Definition
| Muscle spindle fibers which help regulate tone |
|
|
Term
| Identify the motor pool organization in the ventral horn of the spinal chord. |
|
Definition
| Neurons that are more medial are for proximal muscles, lateral=distal muscles, dorsal=flexor, ventral=extensor |
|
|
Term
| Intermediate grey matter from T1 to L2/3 is composed of interneurons that link sensory and motor function as well as mediate visceral function, what is the name of the pre-ganglionic sympathetic neurons that form a column of cells in this region? |
|
Definition
| Intermediolateral cell column |
|
|
