Topic Mix
What is the precursor to dopamine?
What does the brain use as a method of pruning?
Apoptosis
What factor increases the probability of trisomy 21?
Age of Mother
In a stroke, what do we need to remember and list the Acronym.
FAST: Facial droop, Arm weakness, Speech difficulty
FXS premutation has how many repeats?
50-200 repeats
The Brain stem is divided into 3 distinct regions. Name them
Hindbrain, Midbrain, Diencephalon
The neural tube gives rise to?
The neural plate
Explain Mosaic Down Syndrome
Occurs in a very small percentage of cases where some of the cells in the body are normal, while
others have trisomy 21.
Explain the 2 types of stroke
Ischemic (lack of blood flow); Hemorrhagic (caused by bleeding).
Full mutation and Pre mutation
What is the law of Bell and Magendie and what does it help with?
Dorsal spinal cord is sensory & ventral side is motor;
Allows inferences about location of spinal- cord damage on the basis of changes in sensation or movement that a patient experiences.
What are growth cones responsive to?
What genes are overexpressed in Down syndrome?
Genes for beta-amyloid and superoxide dismutase (SOD) are overexpressed.
What is the Circle of Willis?
A collection of arteries that supplies blood to the brain and surrounding structures.
In FXS patients, Elongation of this CGG repeats allows for?
Hypermethylation of FMR1 gene
What is the difference between Spatial and Temporal Summation
Spatial summation - EPSPs & IPSPs that happen close together in space will be summed;
Temporal summation - EPSPs & IPSPs that happen close together in time will be summed.
Mention 4 out of the 7 neurodevelopmental stages and explain 2
1. Neurogenesis : Largely complete by 5 months (prenatally); During this time, brain is resilient to injuries (i.e. teratogens) and/or trauma;
2. Cell Migration: Begins just after neurogenesis is complete; Lasts for ~6 weeks.
3. Cell Differentiation: Begins during migration, continues after migration is complete; More-or-less complete at time of birth.
4. Cell Maturation: This process occurs for years, well into adulthood; Growth of dendrites and axons;
5. Synaptogenesis: Each neuron begins forming its own networks; Can synapse with hundreds or thousands of other neurons;
6. Cell Death: If you don’t use it, you lose it;
7. Myelogenesis Neuronal networks become more efficient in their communication; Sign of neurodevelopmental maturity; Occurs well into adulthood
What is Oxidative Stress?
The imbalance between production and removal of oxygen-derived free radicals
What are the 2 ways an ischemic stroke can happen to you?
Thrombosis: obstruction of a blood vessel by local blood clot;
Embolism: obstruction due to an embolus (traveling particle or debris in the bloodstream; G. wedge, plug) from elsewhere in the body;
FMRP has the highest concentration where in the body?
The brain and the testes
3 reasons why direction matter in mTBI's?
How do cells get to their destination?
The Subventricular Zone (SVZ) contains a primitive map of the cerebral cortex; Cells formed in certain regions of the SVZ migrate to certain cortical locations.
Radial Glial Cells then form a path that extends from the SVZ to the surface of
the cortex; Undifferentiated progenitor cells follow this path.
Hyperactivity of Superoxide dismutase produces more______, which reacts with _____, to form ______
Hydrogen peroxide(H2O2), ferrous iron (Fe2+), Hydroxyl radical (OH)
What are the 4 main types of Hemorrhagic Stroke?
1. Epidural*: between skull and dura matter;
2. Subdural*: between the dura matter and arachnoid space;
3. Sub-arachnoid: between arachnoid space and pia matter;
4. Intracerebral: bleeding within the brain itself. Either from the brain tissue (intraparenchymal hemorrhage) or from the brain’s ventricular system (intraventricular hemorrhage).
* Some consider these not to be hemorrhagic strokes
FMRP in patients with FXS is affected how?
Silencing or reduced production of a protein called fragile X mental retardation protein (FMRP), which is important for normal brain development.