Term
| Epilepsy: Provide the names of the three types of epileptic seizures and give a brief explanation of each type. |
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Definition
Generalized Tonic Clonic Seizures: Entire body seizure, could have vision, taste, smell, or sensory changes, hallucinations, or dizziness before the seizure
Absence seizures: Brief sudden lapse of conciousness. Regain full awareness instantly and have no memory fo the incident. Signs include vacant stare, no motion without falling, eyelid flutters, lip smacking, and hand movements.
Partial Seizure: Trigger is limited to a specific region of the brain. Can have a variety of symptoms depending on what part of the brain is effected. These include abnormal muscle contractions or sensations, hallucinations, and nausea.
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Term
| Creutzfeldt-jakobs disease. Little is known about how prions result in neurodegeneration. Outline one potential source of neurodegeneration in CJD |
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Definition
| One way neurodegeneration can occur is through removal of the normal function of the PrPc protein. When this protein is misfolded into a new conformation it is possible that the protein looses its normal function. This function is not known but it has been proposed it can have anti-apoptotic or anti-oxidant properties. If one of these functions is removed you expose the cell to apoptosis or to damage through oxidation. |
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Term
| Huntington's disease: Describe the molecular pathway affected by the drug, tetrabenzine, commonly used to treat symptoms of huntington's disease? In your answer, provide an explanation for why this therapy is only a treatment and not a cure for the disease. |
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Definition
Tetrabenzine acts to lessen the chorea seen with huntington's disease. This is an abnormal involuntary movement. It does this by decreasing the amount of dopamine. Vesicular monoamine transporters move dopamine into vesicles but the drug binds to this transporter and inhibits it. The drug also binds to the post-synaptic receptors for dopamine preventing the binding of dopamine.
This treats one of the symptoms but the disease is caused by a toxic protein that results from a mutant gene that is inherited. So this drug does nothing to prevent the production toxic effect of the protein. |
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Term
| Schizophrenia: What are some of the positive and negative symptoms of schizophrenia? which part of the brain is associated with each type of symptom when treating patients? what types of drugs are used to treat positive and or negative symptoms? |
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Definition
A positive symptom is a new abnormal thing such as hallucinations or dellusions and a negative is the absence of a normal thing such as lack of emotion or interest in daily activities.
Temporal Lobe: autidory and visual hallucinations, positive, drugs that inhibit dopamine receptors clozapine.
Limbic systems: problems here can cause abnormal lack of connections with people. Drugs that excite glutamate receptors. |
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Term
| Autism: Rett's syndrome is one of the few autistic disorders that can be attributed to a specific genetic mutation. Name the mutated gene in Rett's, provide a brief hypothesis why a mutation int he gene leads to arrested brain development, and finally give a genetic explanation for why this disease is seen almost exclusively in girls and not boys. |
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Definition
•MECP2 gene mutation It appears to help regulate gene activity (expression) by modifying chromatin, the complex of DNA and protein that packages DNA into chromosomes. So if this protein is not functioning normally then it cannot regulate gene expression in the way it should. Epigenetic modifications to genes that this protein may play a part of could be integral in developing the brain.
This is an X linked gene and so when a boy inherits the disorder the effects are extreme and the boy commonly dies at a young age. Gives have 2 x chromosomes and thus can have less severe symptoms with the expression of the normal gene and the mutant gene. |
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Term
What are 3 of main neurotransmitters involved in addiction? Explain the basis of a drug addiction pathway (nicotine, cocaine, heroin or methamphetamines): what happens in the synapse, how are the receptors and reuptake channels affected? Why do some people continue to stay addicted to drugs and then go through withdrawal symptoms when they stop using the drug? |
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Definition
| The main neurotransmitters involved with addiction are GABA, glutamine, and dopamine. With nicotine the pathway involved nicotinic acetylcholine receptors. These receptors bind nicotine and this causes and upregulation of the nicotinic receptors on the post synaptic cell. The post synaptic cell then requires a large concentration of nicotine and acetylcholine to activate. So when you stop using the drug the acetylcholine released into the synapse is not enough to trigger a response creating a general bad feeling as the post synaptic cell is typically dopaminergic. |
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Term
| Provide an explanation for the cellular condition observed in TBI patients known as diffuse axonal injury.What makes diagnosing diffuse axonal injury in traumatic brain injury patients so difficult? |
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Definition
| Diffuse axonal injury is a result of influx of sodium through channels that damaged in the collision. The increased sodium triggers the influx of calcium into the cell which activates proteolytic enzymes that do further damage to the cell resulting in the breaking of the axon. This is hard to diagnose because our imaging techniques are not advanced enough to see the injury and the symptoms can vary largely depending on the region of the brain injured most. |
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Term
| List one type of ALS and describe why it is so difficult to diagnose a definitive type in people afflicted with this disease. Be sure to explain some symptoms of this type of ALS in your answer. |
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Definition
| ALS cannot be diagnosed by any sure test. They main method of diagnosis is through the presentation of symptoms. Due to the similarity between the effects of the types of ALS and to other diseases such as multiple sclerosis it can be hard to diagnose a single type. Limb onset ALS typically sees an early impairment of the limbs through the upper motor neurons and the lower motor neurons. symptoms would include weakness of limbs and twitching. |
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Term
| Glioblastoma: Fluorescence-guided surgery. Describe how this works and exxplain why it can be beneficial in removing a tumor an preventing further spread. |
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Definition
| Glioblastoma tumors are commonly fibrous and have branches that can go off in various directions making them hard to distinguish and remove. So fluorescence guided surgery can help solve this problem by marking the tumor tissue with a fluorescent molecule so that surgeons can see exactly where the tumor is and remove more of it then they may have before. |
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Term
| MS involves the progressive degeneration of nervous tissue in both the peripheral and central nervous system. Briefly describe the primary regions of the nerve cells that aare damaged by MS and provide an explanation for why this type of damage leads to reduced or loss of nerve conduction. |
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Definition
| Immune system attacks mylein sheaths and damages them. This results in the release of cytokines and subsequent inflammation. Symptoms vary. No conconduction. |
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