Sir John B. Gurdon and Shinya Yamanaka

Two pioneers of stem cell research have shared the Nobel Prize for medicine or physiology

John Gurdon from the UK and Shinya Yamanaka from Japan were awarded the prize for changing adult cells into stem cells, which can become any other type of cell in the body.

Prof Gurdon used a gut sample to clone frogs and Prof Yamanaka altered genes to reprogramme cells.When a sperm fertilises an egg there is just one type of cell. It multiplies and some of the resulting cells become specialised to create all the tissues of the body including nerve and bone and skin.

It had been though to be a one-way process - once a cell had become specialised it could not change its fate.

In 1962, John Gurdon showed that the genetic information inside a cell taken from the intestines of a frog contained all the information needed to create a whole new frog. He took the genetic information and placed it inside a frog egg. The resulting clone developed into a normal tadpole.

Forty years later Shinya Yamanaka used a different approach. Rather than transferring the genetic information into an egg, he reset it.

He added four genes to skin cells which transformed them into stem cells, which in turn could become specialised cells.

The discoveries of Gurdon and Yamanaka have shown that specialized cells can turn back the developmental clock under certain circumstances.

These discoveries have also provided new tools for scientists around the world and led to remarkable progress in many areas of medicine.

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Joseph Lister

Joseph Lister (5 April 1827 – 10 February 1912) was a British surgeon and a pioneer of antiseptic surgery, who promoted the idea of sterile surgery while working at the Glasgow Royal Infirmary. Lister successfully introduced carbolic acid (now known as phenol) to sterilise surgical instruments and to clean wounds, which led to a reduction in post-operative infections and made surgery safer for patients.

Lister was interested in surgery from an early stage - he was present at the first surgical procedure carried out under anaesthetic in 1846. Lister continued his studies in London and passed his examinations, becoming a fellow of the Royal College of Surgeons in 1852. He was recommended to visit Professor of Clinical Surgery James Syme (1799-1870) in Edinburgh and became his dresser, then house surgeon and then his son-in-law.

Lister moved to Glasgow in 1860 and became a Professor of Surgery. He read Pasteur's work on micro-organisms and decided to experiment with using one of Pasteur's proposed techniques, that of exposing the wound to chemicals. He chose dressings soaked with carbolic acid (phenol) to cover the wound and the rate of infection was vastly reduced. Lister then experimented with hand-washing, sterilising instruments and spraying carbolic in the theatre while operating, in order to limit infection. His lowered infection rate was very good and Listerian principles were adopted throughout many countries by a number of surgeons. Lister is now known as the ‘father of antiseptic.

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Robert Koch

Robert Koch is considered to be one of the founders of the field of bacteriology. He pioneered principles and techniques in studying bacteria and discovered the specific agents that cause tuberculosis, cholera, and anthrax. For this he is also regarded as a founder of public health, aiding legislation and changing prevailing attitudes about hygiene to prevent the spread of various infectious diseases. For his work on tuberculosis,he was awarded the Nobel Prize in 1905.

While in Berlin, Koch became interested in tuberculosis, which he wasconvinced was infectious, and, therefore, caused by a bacterium. Several scientists had made similar claims but none had been verified. Many other scientists persisted in believing that tuberculosis was an inherited disease. In sixmonths, Koch succeeded in isolating a bacillus from tissues of humans and animals infected with tuberculosis. In 1882, he published a paper declaring that this bacillus met his four conditions--that is, it was isolated from diseased animals, it was grown in a pure culture, it was transferred to a healthy animal who then developed the disease, and it was isolated from the animal infected by the cultured organism. When he presented his findings before the Physiological Society in Berlin on March 24, he held the audience spellbound, sological and thorough was his delivery of this important finding. This day has come to be known as the day modern bacteriology was born.

Koch determined guidelines to prove that a disease is caused by a specific organism. These four basic criteria, called Koch’s postulates, are:

1.       A specific microorganism is always associated with a given disease.

2.       The microorganism can be isolated from the diseased animal and grown in pure culture in the laboratory.

3.       The cultured microbe will cause disease when transferred to a healthy animal.

4.       The same type of microorganism can be isolated from the newly infected animal.

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Stanley Lloyd Miller

Stanley Lloyd Miller born in Oakland, California (March 7, 1930) an American chemist and biologist who is known for his studies into the origin of life, particularly the Miller–Urey experiment which demonstrated that organic compounds can be created by fairly simple physical processes from inorganic substances. However, it has since been demonstrated that the conditions used for the experiment may not have been an accurate representation of the early Earth atmosphere.

He studied at University of California at Berkeley (earning his B.Sc. in 1951) and then at University of Chicago where he earned his Ph.D. in chemistry in 1954. While at Chicago, Miller was a student of Harold Urey.

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Robert W. Holley

Holley, Robert William, 1922-93, American biochemist, b. Urbana, Ill., Ph.D. Cornell, 1947. He was a professor at Cornell (1948-68) before he joined (1968) the Salk Institute, and he continued an association with Cornell after 1968. Holley received the 1968 Nobel Prize in physiology or medicine jointly with Har Gobind Khorana and Marshall W. Nirenberg for their interpretation of the genetic code and its function in protein synthesis. Holley is credited with isolating transfer RNA (tRNA) and then determining the sequence and structure of alanine tRNA, which incorporates the amino acid alanine into proteins. Knowledge of the structure of tRNA was key to explaining how proteins are synthesized from messenger RNA.

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Antony van Leeuwenhoek

Anton van Leeuwenhoek was a linen merchant in Delft, the Netherlands, whose passion for science helped make him one of the most important figures in the history of microbiology.

Van Leeuwenhoek saw his first microscope, in use in the fabric trade, in 1653, and he soon bought one of his own. He read Robert Hooke's Micrographia, and it reportedly enthralled him.

By 1668, he was grinding lenses for his own simple microscopes and looking at every tiny thing he could find. Those two things — his boundless curiosity and the fact that he kept improving his lenses were critical to his discoveries.

Van Leeuwenhoek was the first to identify microorganisms, notably protists and bacteria, and the first to describe red blood cells and sperm.

Van Leeuwenhoek's discoveries were documented in letters he wrote to Henry Oldenburg, secretary of the Royal Society of London, between 1673 and Van Leeuwenhoek's death in 1723. The letters made him famous, and the Royal Society made him a fellow in 1680.

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Edward Jenner

Edward Jenner was born in 1749, in Berkeley. He wanted to get rid of small pox for ever so he carried out a simple experiment, which turned out to change everyone's lives for the better.

Edward Jenner noticed that cows sometimes got a disease called cowpox. Because the milkmaids had to milk the cows, they often also caught cowpox…but it didn't seem to harm them. Edward Jenner was intrigued - milkmaids that had caught cowpox never seemed to catch the contagious and deadly smallpox, which thousands of people died from. Edward Jenner came up with a theory, that cowpox prevented people from getting smallpox. To test his theory, Edward Jenner needed to find someone who was young and who hadn't caught smallpox or cowpox before. He found a boy called James Phipps (aged 8) and explained his idea. Edward Jenner then took some pus from a milkmaid's cowpox and rubbed it into two small incisions on James's arm. Soon after, James became ill with cowpox but the symptoms didn't last long. 6 weeks later, Jenner took some pus from a smallpox victim and again put it into James's cuts. However, this time James didn't catch the disease. Cowpox was called vaccinia so he called his invention the vaccine.

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Craig Venter

John Craig Venter (born October 14, 1946) is an American biologist and entrepreneur. He is known for being one of the first to sequence the human genome and for creating the first cell with a synthetic genome. Venter founded Celera Genomics, The Institute for Genomic Research (TIGR) and the J. Craig Venter Institute (JCVI), and is now working at JCVI to create synthetic biological organisms. In  1984, he moved to the National Institutes of Health campus where he  developed Expressed Sequence Tags or ESTs, a revolutionary new strategy  for rapid gene discovery. Using ESTs he and his team discovered thousands  of new human genes while at NIH. In 1992 Dr. Venter founded The Institute  for Genomic Research (TIGR), a not-for-profit research institute, where in  1995 he and his team decoded the genome of the first free-living organism,  the bacterium Haemophilus influenzae, using his new whole genome shotgun  technique. This led to the rapid  and accurate decoding of hundreds of  important genomes including human viral and bacterial pathogens,  environmental microbes, insect, plant and mammalian genomes.  In 1998, Dr. Venter founded Celera Genomics to sequence the human  genome using new tools and  techniques he and his  team developed. This  research culminated with the February 2001 publication of the human genome  in the journal,  Science. He and his team at Celera also sequenced the fruit  fly, mouse and rat genomes.

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