Illness is a fact of human life, and medicine has been our response to making people better. The science of medicine stretches back through the earliest civilisations, and the development of drugs has seen an evolution from natural remedies to modern use of chemical engineering to produce specific drugs targeting specific problems. Diseases can be traced back to prehistoric days, although we have no writing to support this, studying the remains of bodies has shown disease. Many diseases can only be seen in organs or flesh but some can be seen on bones.
We can also see general injuries like broken bones and damage joints and backs, however close study of bones has shown signs on bone cancer, anaemia and other nutritional diseases. Prehistoric times aslso show evidence of the first signs of Trephining (an operation on the scull to remove a part of it) a technique still used today. Hippocrates was an ancient Greek philosopher. He wrote the “Hippocratic books” showing a new type of Greek medicine, concentrating not on illness but on the patient. He wanted doctors to focus in on the patient and observe them carefully, to find the physical causes of their illness.
He did this and recorded it so he could use the knowledge to help other patients in that case. His work has influence the Hippocratic Oath that doctors take these days in medical practise. Hippocrates suggested that the body was made up of four different humours: yellow bile, black bile, blood and phlegm, with them having a particular season they rise in levels. He found this by studying illnesses such as cold and flu being more common in winter, hence phlegm being in the winter. The romans were one of the first to develop public health projects. They provided sewers and clean water for their towns and cities.
This is still used today with more technology used. During the plague in 293BC the romans imported a scared snake form Epidaurus; this continued to be the treatment of sick throughout the roman period. Galan around in 129AD restored the Hippocrates standards, especially the idea of very close patient observation. He developed many treatments based on the theory of the four humours. He also became very aware of the human anatomy; he knew and recorded views of organs. Fighting disease became more of a focus around the 1800’s. Medicine was being created around this time: Seacole and nightingale 1854-59 Pasteur’s germ theory 1857-95.
Koch and vaccinatio0n 1872-1910 Ehrlich’s “magic bullet” 1889-1915 Fleming and penicillin 1918-42 Again by 1800’s surgery was become more common practise: 1840’s William Morton uses ether. James Simpson uses chloroform 1867-70 Joseph Lister pioneers antiseptic surgery 1880’s Willian Halsted introduces protective surgical clothing 1910’s Archibald Mclndoe develops plastic surgery 1960’s Christian Barnard performs the first transplant. Aspirin Rheumatism is a condition the affects joints, in a similar way to that of arthritis. It can become very painful and lead to stiffness of joints and lack of mobility.
Treatment for rheumatism began thousands of years ago with the use of remedies or extracts from herbs and plants, such as the bark or leaves from a willow tree, which contain salicylic acid. The development of synthetic salicylate began with Felix Hoffman, working at the Bayer Company in Germany. He made the acetylated form of salicylic acid in 1897; named “aspirin” the drug quickly became the most widely used medicine of all time. In 1971, vane discovered the way by which aspirin gives out its anti-inflammatory, analgesic (pain killing) and antipyretic (fever reducing) actions.
He proved that aspirin and other non-steroid anti-inflammatory drugs (NSAIDs) inhibit the activity of the enzyme now called cyclooxygenase (COX) which leads to the formation of prostaglendins (PGs) that cause inflammation, swelling, pain and fever. However, by inhibiting this key enzyme in PG synthesis, the aspirin-likle drugs also prevented the production of physiologically important PDs which protect the stomach mucosa from damage by the hydrochloric acid, maintain kidney function and aggregate platelets when required.
The analgesic (pain killing), antipyretic (fever reducing), and anti-inflammatory effects of acetylsalicylic acid were caused by the functional groups of the molecule. What happens is the functional groups of the Acetylsalicylic acid have irreversible effects on the activity of both types of cyclooxygenase (COX-1 and COX-2) to decrease the formation of precursors of prostaglandins and thromboxanes from arachidonic acid. This means that swelling or inflammation is reduced as is temperature due to infection and also pain receptors are interfered with.
The effect of aspirin is therefore permanent because the molecule binds to tissues and is only removed when the tissues are replaced. This is different to ibuprofen which only has temporary effect on the tissues. The platelet aggregation-inhibiting effect of acetylsalicylic acid specifically involves the compound’s ability to act as an acetyl donor to cyclooxygenase; the nonacetylated salicylates have no clinically significant effect on platelet aggregation. Irreversible acetylation renders cyclooxygenase inactive, thereby preventing the formation of the aggregating agent thromboxane A2 in platelets.
Since platelets lack the ability to synthesize new proteins, the effects persist for the life of the exposed platelets (7-10 days). This is why aspirin is given as a blood thinner to heart disease and stroke patients – it prevents blood clots forming. Iodoform • find out about the principles of drug action in terms of the chemical structure of a drug and receptor sites in the body; • find out about how a drug gets into the body and its site of action; Iodoform is a compound with the formula CHI3.
A pale yellow, crystal, volatile substance, it has a penetrating odour (it is often referred to as the hospital smell) and, analogous to chloroform, sweetish taste. It is sometimes used as a disinfectant, also known as tri-iodomethane, and is sometimes referred to as carbon triiodide or methyl triiodide. Iodoform (in the form of a gauze pad) has the following effects on humans: •Headaches •Mental disorders •Sleepiness •A weak pulse •Clumsiness •Difficulty sleeping •Confusion •Low moods •A general feeling of being unwell. We would particularly expect to see sleepiness and a weak pulse due to the anaesthesia.
The anaesthetic properties of iodoform vapour are not as good as those of general anaesthetics. Iodoform is chemically similar to chloroform, which is used in much the same way. There are a number of possible ways the chloroform can affect the body (and these may be similar for Iodoform). The Meyer-Overton theory states that anaesthetics dissolve in cellular membranes. This causes structural distortion of the membranes. The distortion may reduce the conduction of a nerve impulse along a nerve cell and this will interfere with sensory perception and pain response.
An alternative receptor theory states that anaesthetics interact with specific proteins. Examples of proteins that may be altered by binding of an anaesthetic are neurotransmitter receptors and ion channels. Anaesthetics may change the conformation (structure) of the protein. In this way the nerve pathway is interfered with. ? Antihistamine What is hay fever? Hay fever is an allergy caused by pollen or dust in which the mucous membranes of the eyes and nose are inflamed, causing running at the nose and watery eyes.
What is histamine and how is it relevant to hay fever sufferers? Histamine is a compound which is released by cells in response to injury and in allergic and inflammatory reactions, causing contraction of smooth muscle and dilation of capillaries. So in reactions to pollens it causes the symptoms of hay fever, that can be treated by the use of antihistamine. What are the biggest antihistamine brands? The biggest antihistamine brands are: pandol extra, Claratyne, Telfast and Zyrtec. What is the chemical formula of a typical brand (e.g. loratadine)?
The molecular formula for Loratadine is C22H23ClN2O2 How does an antihistamine reduce the hay fever symptoms? Histamine is a chemical that is produced in the body. Large amounts of histamine are made in cells called mast cells in places here the body comes into contact with the outside environment. Here the mast cells and histamine from part of the immune defence system. The cells of the immune system constantly monitor blood and mucosae for anything that is not made by the body.
If the skin is damaged or the immune system detects a foreign substance, histamine is released from mast cells. The histamine binds to special receptors on other cells called H1 receptors. This sets off a chain reaction which causes blood vessels in the area to become slightly leaky. Specialised cells and chemicals, which defend the body, can now get access to the area. While this is a helpful response, it also causes redness, swelling and itching. Allergic reactions such as hay fever are caused by an oversensitivity of the immune system to a particular allergen.
An allergen is a substance that is foreign to the body and which can cause an allergic reaction in certain people. In most people, the immune reaction to these foreign substances is normal and appropriate. But in allergic people, it is excessive. For example, in people with hay fever, contact with pollen in the nose, throat and eyes triggers the mast cells there to release much more histamine than normal. This excessive release of histamine produces the associated symptoms of itching, swelling, runny eyes, etc.
Antihistamines work by physically blocking the H1 receptors, stopping histamine from reaching its target. This decreases the body’s reaction to foreign substances and therefore helps to reduce the troublesome symptoms associated with allergy. Antihistamines are also used in the treatment of nausea and vomiting. However the exact way that they ease these symptoms is not fully understood.
The brain has several key areas which control vomiting. It is thought that antihistamines block H1 receptor in the area of the brain which creates nausea in response to chemicals in the body.