Tuesday, September 18, 2012

Screening for Glaucoma - Preventive Medicine


Glaucoma is silent and early detection is essential. Permanent loss of vision is the end result. Yearly examinations by a vision specialist, of your choice, will screen for the early onset of glaucoma.

Your body keeps you in balance without your knowledge. This is called homeostasis. In the eye a fluid keeps the shape of the eye perfect for you to see well. Fluid balance maintenance is very important. 

In your eye, fluid enters the internal chamber from small blood vessels called capillaries. These capillaries are found at the arterial end of blood vessels that supply fluid to your body systems. These small tubes are only one cell layer thick. At the same time, fluid is reabsorbed back into the circulatory system through venous capillary beds that return blood to the heart. 

This inflow and outflow of fluid from the chamber of the eye is perfectly balanced. Why is this important? Liquids are not compressible. This is why early detection is essential. If the rate of fluid formation, in the eye chamber, is greater than the rate of reabsorption internal pressure in the eye increases. This slowly increasing pressure destroys the optic nerve of the eye if it is allowed to continue undetected. Glaucoma is abnormal pressure buildup in the internal chamber of the eye. 

This is not temporary. It results in permanent blindness. A vision specialist will prescribe a liquid medication that prevents the pressure buildup. You have to take the medication for the rest of your life.

There are non-profit groups that routinely test people with a machine called a tonometer. It measures internal eye pressure. They screen for values that may indicate you need to see a vision specialist for further tests.

Glaucoma may indicate a capillary condition that results from diabetes. Diabetes is controllable but there is not a cure for diabetes. If you are diabetic your chance of suffering from glaucoma is high.

Monday, September 17, 2012

A Different Way to Look at Oxidation and Reducton

Oxidation and Reduction

Glucose is a simple sugar that provides, in small steps, a way to produce energy (ATP) . Cellular Oxidation or Cellular Respiration is:  Oxygen + Glucose breaks down into Carbon Dioxide and Water and Energy. The reverse of this equation is Photosynthesis where the Energy is supplied by the Sun that raises an Electron to a Higher Energy Level.

Oxidation is a gain of Oxygen
Reduction is a loss of Oxygen

That explains Oxidation and Reduction. It also means, in an Equation, if something is Oxidized then something else is Reduced. There are Cycles in our cells that make this possible by rearranging atoms and molecules to make  it all possible.

This means there is another way to state what happens to a atom or molecule in an Oxidation and Reduction reaction.

Here is a summary of the different ways to view Oxidation and Reduction.

Oxidation is:

A Gain of Oxygen

A Loss of Electrons
A Loss of Hydrogen

Reduction is:

A Loss of Oxygen

A Gain of Electrons
A Gain of Hydrogen

Household Cleaner, like Chlorine Bleach, is a good way to see Oxidation and Reduction in action. Chlorine, by itself, likes to steal electrons from whatever it touches. If it grabs an electron form something else, the Chlorine atom is reduced. The substance that losses its electron is oxidized. That why they say Chlorine Bleach is a great oxidizing agent used in cleaning.

To the Chemists, well, it is a little simple.

If you look at The Periodic Table that lists all the Elements you find an arrangement of particles found in each element. These particles make up the nucleus of each and every atom and contribute to a hazy electron cloud that surrounds each atom.

The nucleus is comprised of Protons (+) and Neutrons (No Charge) while the Cloud contains Electrons ( - ). In elemental form each atom of an element is neutral as far as a electrical charge.

Chlorine is placed in a group of elements that are very reactive. (They all like to steal electrons)
Why? In nature we all try to achieve an equilibrium of comfort. Thats life! Atoms have a different way to achieve comfort.

In an atom, when it is "neutral" as far as charge is concerned,  the number of Protons (+) in the nucleus is the same as the number of Electrons ( -)  zipping about in the electron Cloud. The overall charge is Zero on the Chlorine Atom. Why can't Chlorine just behave itself?

For an Element, like Chlorine, the Electrons whirl about the Chlorine Nucleus in several different rings or Energy Levels. To achieve stability, hence peace and quiet, an atom needs just 8 electrons in that outermost ring. Chlorine only has 7 electrons in its outermost ring. It is so reactive it steals another electron from some other element.

Keep in mind, the  number of Protons in the Nucleus doesn't change. Forget the Neutrons for this discussion.

When Chlorine "steals" an Electron from some other Element it now has 8 Electrons in its outermost Energy Level. It now has achieved electronic stability. Now,the overall Charge on the Chlorine Atom, before stealing, was Zero. What is it now? Remember, originally the number of Protons and Electrons were the same. If you add one electron the overall charge on the Chlorine is a negative ( - ) 1.  Due to stealing the electron the Chlorine Oxidizing Agent (used in disinfecting or cleaning) is Reduced (gained an electron) and become a negatively charged Ion! Therefore, all Elements or Molecules with an overall Charge are ions. Some simple and some Complex!

A Sodium Atom is the opposite of a Chlorine Atom. Sodium, using a line of reasoning like for Chlorine, needs to lose an Electron for stability. Guess where Chlorine got its Electron it needed. You are right! From Sodium. Sodium now has an overall Positive charge and become a positive charged Ion. When Table Salt is formed a Chlorine ion and a Sodium Ion unite in what is an Electrostatic Bond that forms a molecule of Sodium Chloride.

Isn't this fun! Since Chlorine was reduced by gaining an electron the Sodium is the Reducing Agent and Sodium was Oxidized (lost its electron) to Chlorine. Hence Chlorine is the Oxidizing Agent.

Whew! See how easy this was? I will leave the discussion now. The above is an Oxidation - Reduction Reaction. One of many that occur in the Oxidation of Glucose to eventually form ATP, a source of storable chemical energy.