PARKINSON'S DISEASE

People Affected and Costs

Parkinson's disease is important to understand because it effects a significant part of the US population around 50,000 people are diagnosed with Parkinson every year, with more than half a million Americans affected at any given time. Also an estimated 7 to 10 million people worldwide are living with Parkinson's disease. However Parkinson's also has a significant impact economically as well. The combined direct and indirect cost of Parkinson’s, including treatment, social security payments and lost income from inability to work, is estimated to be nearly $25 billion per year in the United States alone. Medication costs for an individual person with PD average $2,500 a year, and therapeutic surgery can cost up to $100,000 dollars per patient.

Causes and Symptoms

Parkinson's disease is a degenerative disorder of the brain. This means that a part of the brain and its function are increasingly deteriorated over time. In Parkinson's this part of the brain is called the basal ganglia and its function is to control movement. The disease is both chronic, meaning it persists over a long period of time, and progressive, meaning its symptoms grow worse over time. The basal ganglia makes the neurotransmitter dopamine which controls our body's movement. Dopamine sends messages to other parts of the brain to coordinate movement. Patients who have Parkinson's Disease have a low amount of dopamine so that means the body doesn't receive the right messages it needs to move normally. Because Parkinson's is a degenerative disorder, it occurs slowly and in stages. In the first stages of Parkinson's a barely noticeable tremor in just one hand. The patients speech may become soft or slurred. However over time these conditions worsen to a point where the person needs assistance with all daily activities. There is no cure for Parkinson's however scientist's have managed to make the diseases progression slower.

Research

There has also been research done on the topic of diagnosing Parkinson's disease, as sometimes diagnosis are not always clear. There are no standard tests to diagnose Parkinson’s. The best way testing for PD is specialized brain scanning techniques that can measure the dopamine level in the system and brain metabolism. Scientists are also exploring the idea that loss of cells in other areas of the brain and body contribute to Parkinson’s. For example, researchers have discovered that one sign of Parkinson’s disease (called Lewy bodies) are found in the mid-brain. This area of the brain deal with non-motor functions such as sense of smell and sleep regulation. The presence of Lewy bodies in these areas could explain why patients experience non-motor functions before any motor related function appear.

Treatments

There are currently three major treatments for Parkinson's. These are medication, surgery and therapy. Medication is the most commonly used method to treat Parkinson's and there are many types of medications that do different things. The main medication used to treat Parkinson's is levodopa and carbidopa. Levodopa alone causes nausea and vomiting once it reaches the brain however it is converted to dopamine once it reaches the brain. Parkinson's patients need this dopamine to suppress their symptoms. Carbidopa works by preventing levodopa from being broken down before it reaches the brain. This allows for a lower dose of levodopa, which causes less nausea and vomiting. This is the best way of curing Parkinson symptom. Another one of these medications are dopamine agonists. These are drugs that stimulate the parts of the rain influenced by dopamine. So the brain is tricked into thinking it is receiving the dopamine it needs. Therefore the symptoms of Parkinson die down. However dopamine agonists are not as effective as the combination of levodopa and carbidopa.

The surgical way of treating Parkinson is through deep brain simulation. This is when surgeon put electrodes into the areas on the brain affected by Parkinson's. Surgeons use using MRI and neurophysiological mapping to put them in the right place. Another device known as the impulse generator is put under the collarbone, providing electrical impulses to part of the brain that deals with motor functions.

ALZHEIMER'S DISEASE

Why understanding about Alzheimer's disease is important?

Alzheimer's disease is a form of dementia which is an umbrella term for a set of symptoms related to memory loss and logical thinking impairments, among other things. Alzheimer is unique because it affects 5.4 million Americans and is the 6th leading cause of death in the US. That means that it affects 1 out of 10 Americans over the age of 65. No one is exempt from the disease and there is no way to actively prevent it. Since the year 2000 the death rates of other diseases such as HIV, stroke and heart disease have decreased, but the death rate of Alzheimer's disease has grown by 66%. The last reason why understanding about Alzheimer's is important because there is no known cure. There are treatments that will slow the progression of the disease but none that will stop it.

What is Alzheimer's disease?

Alzheimer's is a disease that affects the brain in many of it's critical functions. It's difficult to diagnose because it may sometimes be confused with just “growing old” or symptoms of too much stress. However, Alzheimer's disease is a very real condition with biological impairments. Because of the way it spreads in the brain, Alzheimer's disease is categorized in separate stages. 

It originates in the hippocampus which is the area in the brain in charge of forming new memories. Alzheimer's patients have difficulty recalling events from a few hours or days ago. The disease then spreads to the part of the brain where language is processed. Thus it becomes harder to recall “the right word”. Next it spreads to the part of the brain where logical thinking takes place. So, it becomes harder to solve problems where complex thought is required. It then progresses to the part of the brain where emotions are regulated, therefore it becomes difficult to respond/control to emotional circumstances appropriately. Next is the part of the brain where senses are perceived, so patient may start to hallucinate. After that it spreads to the part of the brain where the persons most oldest memories are stored. Late stage of Alzheimer's disease is where balance and coordination of a person deteriorates causes them to be wheelchair bound. The last stage is where the persons breathing and heart regulation is affected, ultimately causing death. All these stages take place in about between 8-10 years time, sometimes more or less depending on the individual.

How Alzheimer's disease takes place?

Research has shown that Alzheimer's disease happens when two unusual substances are produced by the brain. These substances are know as Plaques and Tangles.

Cell membranes of neurons process proteins. Plaques are formed when proteins in the neurons cell membrane are processed abnormally. In a normal neuron an enzyme known as alpha-secretase cut apart a protein called APP (Amyloid Precursor Protein), a normal and in fact vital substance needed for the cell. A second enzyme known as gamma-secretase cuts another part of APP. The two released fragments from these enzymes are normal. In patients suffering from Alzheimer's disease the first cut of APP is made by an enzyme called beta-secretase instead of alpha-secretase, this combined with the second cut of APP by gamma-secretase releases a part of APP known as beta amyloids. The beta amyloids clump together and become bigger and bigger until they form structures known as plaques. Plaques are too big in size and are insoluble in cerebral fluid. Plaques attach themselves to the neuron membrane. This triggers the brain to release powerful chemicals, however these powerful chemicals backfire because they set of a series of reactions that destroy the neuron.

Tangles are formed inside the neurons in contrast to plaques which are formed outside the neurons. Tangles are made when a protein known as Tau is modified inside a neuron. Tau is a protein that keeps together an organelle inside neuron known as microtubules. Microtubules are tube like strands inside the neuron that transport important materials to all parts of the neuron. In Alzheimer's disease tau protein becomes hyperphosphorylated (Phosphorylation is the process of addition of phosphate groups), which means that an extra phosphate group cannot be added to tau. This causes the tau to separate from the microtubules causing them to fall apart. These abnormal tau bond together inside of the neuron and makes structures know as “tangles”, which disrupts the normal functioning of neurons.