Oates was born in Putney, London, England in 1880. His parents were William and Caroline Oates. His family was rich. They had owned land at Gestingthorpe, Essex, for hundreds of years. His father moved the family there when his children were small. He had an older sister, named Lillian, who married an Irish singer and actor. His uncle was a naturalist and African explorer. Oates studied at Eton College, but he left after less than two years because of poor health. He then attended an army school in Eastbourne.
In 1910, he joined Robert Falcon Scott's expedition to the South Pole. He was chosen because he had worked with horses. He took care of the nineteen ponies that pulled the sleds carrying food for the trip. Scott then picked Oates for the five-man team to travel the last distance to the Pole.
Captain Scott, Captain Oates and 14 others left base camp on November 1,1911. During the trip, some members of the crew were sent back by Scott in teams. On January 4, 1912, only the five-man team with Scott and Oates, were left to walk the last to the Pole.
On January 18, 1912, they reached the Pole. They found that Norwegian explorer, Roald Amundsen and his team, had beaten them to be first to the Pole. Inside the tent was a note from Amundsen saying that he had reached the South Pole on December 14, 1911.
On the way back, Scott's team had many problems: very bad weather, poor food supply, injuries from falls, scurvy and frostbite. On February 17, 1912, Edgar Evans died from a head wound after falling into a deep crack in the ice a few days earlier.
Oates' feet were badly frostbitten. He was getting weak faster than the others. In his diary, Scott wrote on March 5: "Oates' feet are in a wretched condition... The poor soldier is very nearly done." The others did not want to leave him behind. This caused the team to be late getting back. They were running out of food and fuel. On March 15, Oates told his friends that he could not go on. He asked them to just leave him in his sleeping bag, but they said no. He travelled a few more miles that day but got worse that night.
When he woke up the next morning, Oates walked out of the tent into a blizzard and temperatures to his death. Scott wrote in his diary, "We knew that poor Oates was walking to his death, but though we tried to dissuade him, we knew it was the act of a brave man and an English gentleman."
Scott and the other two walked another . Then they were stopped by a fierce blizzard on March 20. Trapped in their tent by the weather and weak, cold and hungry, they died nine days later. Their frozen bodies were found by a search party on November 12, 1912.
Oates' body was never found. Near where they thought he died, the search party left a pile of stones and a cross. These words were left: "Hereabouts died a very gallant gentleman, Captain L. E. G. Oates... In March 1912, returning from the Pole, he walked willingly to his death in a blizzard, to try and save his comrades, beset by hardships."
Oates' reindeer-skin sleeping bag was found. It is now in the museum of the Scott Polar Research Institute in Cambridge, with other items from the expedition.
Scott wrote in his diary that before Oates left the tent and walked to his death, he said "I am just going outside and may be some time."
Pharmacokinetics
Pharmacokinetics is a branch of pharmacology which studies what the body does to a drug. Pharmacokinetics looks at how a substance enters, moves through and exits the body. It relates how the dose delivered affects the concentration within the body. It is closely related to another branch of pharmacology, pharmacodynamics, which describes how a drugs affects the body.
When developing new drugs, it is important to know exactly what happens to the chemical once administered. There are four important parameters of pharmacokinetics, usually known by the acronym ADME: Absorption, Distribution, Metabolism and Excretion. This model was developed in order to simplify perception of the many processes that take place once a drug enters an organism.
Absorption describes the movement of a drug from the dosage form to the site of action, usually the blood.
The bioavailability (F) of the drug is the fraction of the drug being administered that reaches the blood circulation.
Once the drug is in the body, it enters many cells. Cells are surrounded by a protective membrane made of lipid bilayer. For this reason, only lipid soluble, (lipophillic) drugs can enter cells.
Sometimes the substance gets trapped within the lipids of waste products that need excreted, and leave the body without ever being absorbed.
For this reason, there must be a balance between lipophilicity and hydrophilicity of drug molecules.
The acidity of a pharmaceutical compound can also affect absorption. It is important to know how acid or basic the substance is in order for the body to accept it, giving our bodies a biological effect.
One way to overcome the need to absorb the drug in the stomach (where it can be destroyed by bile), is to inject it in the skin (intradermal), subcutaneously, in the muscle (intramuscular) or directly into the bloodstream (intravenously).
Other routes include the topical route, where the drug is applied directly to the skin or mucosal surface on which it is intended to act. These drugs are also known as ointments and include eye drops, thrush cream and eczema lotion. Though absorption is slow, there is a high concentration of the substance in this one area, meaning a pharmacological affect at only the site of application is produced.
Nasal spray and inhalers are other routes of admission which bypass the stomach.
Distribution describes the process by which a drug moves about in the body once it has entered blood circulation, and how this movement may decrease the concentration.
The apparent volume of distribution (Vd) is the apparent volume into which the drug is distributed, expressed in liters (L).
Vd = Dose/Initial plasma concentration
Vd is a hypothetical volume of fluid that will contain the total amount of drug administered to the body. One inside thebody, the drug can move around either by diffusion (soaking through a membrane due to a lower concentration), or by transport in the blood. The body should be considered as being multicompartmental, where drugs can be distributed into plasma (blood) - 8% , interstitial fluid (a liquid that surrounds tissues) - 24%, intracelullar fluid (which surrounds cells) - 65% and also fat.
A lower Vd value infers that the drug is retained within the plasma.
A higher Vd value suggests that the drug is retained in volumes outside of the plasma (i.e. in peripheral tissues).
There are many factors which affect drug distribution, the most important ones are the following:
Metabolism describes the process by which a drug is altered chemically in the body into its metabolite, which may be more or less active. This process usually occurs in the liver, but can also take place in the plasma, lungs, stomach, small intestine, kidney and skin. It contains two phases: phase 1 and phase 2.
Put simply, this process converts lipid soluble drugs to water soluble metabolites.
All drugs that are absorbed from the small intestine are first transported to the liver by the hepatic portal vein, in many cases a large proportion of the drug is then metabolized immediately before the drug enters the systemic circulation. This process is called first pass metabolism.
Some drugs undergo extensive first pass metabolism such that only about 10% of the administered dose enters the circulation: "10% bioavailability".
In the case of some drugs, the metabolism occurs within the gut before even reaching the liver.
Can be zero order or first order:
This is an elimination process by which a drug or its metabolite is removed from the body. Usually this occurs in the kidneys (urine), but can also take place in the biliary system (faeces), gastrointestinal tract (GIT), skin (sweat) and lungs (expired air).