WHO WAS KARL LANDSTEINER?

Austrian biologist Karl Landsteiner (1868-1943) is mostly known for his pioneering work in the classification of blood groups. However, he was also responsible for many other discoveries in the field of medicine that have helped improve immunity and health.

Born in Vienna, Karl lost his father at an early age and was brought up by his mother. After his schooling, he studied medicine at the University of Vienna and later took up research in the field of organic chemistry. He worked under many renowned chemists of the time. During his research at the Institute of

Hygiene in Vienna, Karl became interested in the   mechanisms of immunity and the nature of antibodies. He soon published his first article on serology- the study of blood.

At the time, blood transfusion was considered risky as it led to fatal blood clotting in the recipient's body. Landsteiner was the first to suggest that blood transfusion may be unsuccessful because an individual's blood might not be compatible with that of another. In 1901, he classified blood types into three groups-A, B and C (later called O). This enabled donors and recipients to match their blood types before transfusions.

A few years later, guided by his work, the first successful blood transfusion was carried out by a doctor in New York. During World War I, the lives of many soldiers were saved due to transfusion of compatible blood.

Landsteiner was also instrumental in the discovery of the polio virus. It was earlier believed that polio was caused by a bacterium. With the help of bacteriologist Erwin Popper, Landsteiner not only proved that polio was caused by a virus but also traced the manner of its transmission. Their discovery made possible the development of a vaccine for polio.

Later, when he moved to New York, Karl teamed up with noted biologist Alexander Wiener to identify the Rh (rhesus) factor that relates human blood to that of the rhesus monkey. The Rh factor, which occurs when the mothers  blood is incompatible with that of the foetus, was believed to be responsible for a fatal infant disease.

Landsteiners discovery of blood groups and studies on the subject earned him the Nobel Prize in Physiology or Medicine in 1930.

Though he was much sought-after as a world authority on the mechanisms of immunity, Landsteiner shunned publicity and preferred a quiet life away from the public gaze. On June 26, 1943, he died following a coronary seizure, while still at work in his laboratory.

Picture Credit: Google

HOW DOCTORS STARTED USING STETHOSCOPES TO DIAGNOSE PROBLEMS WITH THE CHEST?

The practice of using stethoscopes started in a hospital in Paris, in the early 19th Century.

The Necker-Enfants Malades Hospital in Paris provided specialised medical care. Rene Laennec, one of the doctors there, was trained to use sound to diagnose diseases of the chest.

One day in 1816, a young woman who had a heart problem came to consult Dr. Laennec. Ordinarily, the physician would have put his ear to the woman's chest and listened to her heartbeats to detect if there was any aberration. But the woman who came to see Dr. Laennec was rather plump. Uncomfortable with the idea of putting his ear to her chest, the doctor's eyes fell on a newspaper lying there...and he got a brainwave!

He rolled the newspaper into a cylinder and applied one end of it to the region of the woman's heart and the other to his ear. And then his own heart thumped in joy and excitement! He could hear her heartbeats more clearly than if he had put his ear directly to her chest. It was a landmark moment in medical science.

Laennec fashioned a hollow, wooden cylinder and catalogued the various sounds he could hear through it when applied to a patient's chest, and what the sounds indicated about the health of the patient. He sent his findings to the Academy of Science, in Paris.

It was not long before his invention began to be used by physicians all over Europe.

Picture Credit : Google 

WHAT AND WHEN WAS THE FIRST HUMAN ORGAN TO BE TRANSPLANTED SUCCESSFULLY?

In 1954, the kidney was the first human organ to be transplanted successfully. Until the early 1980s, the potential of organ rejection limited the number of transplants performed.

 The first ever successful transplant of any organ was done at the Brigham & Women's Hospital in Boston, Ma. The surgery was done by Dr. Joseph Murray, who received the Nobel Prize in Medicine for his work. The reason for his success was due to Richard and Ronald Herrick of Maine. Richard Herrick was a in the Navy and became severely ill with acute renal failure. His brother Ronald donated his kidney to Richard, and Richard lived another 8 years before his death. Before this, transplant recipients didn't survive more than 30 days. The key to the successful transplant was the fact that Richard and Ronald were identical twin brothers and there was no need for anti-rejection medications, which was not known about at this point. This was the most pivotal moment in transplant surgery because now transplant teams knew that it could be successful and the role of rejection/anti-rejection medicine.

Credit : Wikipedia 

Picture Credit : Google 

WHAT TYPE OF VACCINE IS R21?

Scientists behind the Oxford-AstraZeneca coronavirus shot have produced the vaccine. "This was by far a much more difficult vaccine to make work." Adrian Hill, the Jenner Institute's director, said in northern Tanzania on a visit to field trials of the R21/Matrix-M malaria vaccine.

While the coronavirus responsible for Covid-19 has 12 genes, Plasmodium-the parasite that causes malaria - has more than 5,000 genes. It's an organism that infects the liver and bloodstream, infecting red blood cells.  Hill explains that R21/Matrix-M combines the R21 vaccine with a vaccine booster or adjuvant Matrix-M, which stimulates the human immune system to attack the parasite.  When an infectious mosquito feeds on a human being, it injects parasites in a form called sporozoites into the bloodstream, where they travel directly to the liver. The sporozoites divide rapidly, producing around 20,000 merozoites that rupture the liver cells and invade red blood cells.  R21 targets a circumsporozoite protein (CSP) present on the parasite's surface during the sporozoite stage. CSP rarely mutates among the four strains of malaria parasites that infect humans. The human body does not readily react with a complete immune response to foreign proteins. The R21 focus on CSP boosted by the proprietary Novavax adjuvant- produces a more robust, better-targeted antibody response.  Clinical trials are now moving to the third phase in four countries across Africa - Mali, Tanzania, Kenya, and Burkina Faso.

Picture Credit : Google 

What are codons?

A codon is a sequence of three DNA or RNA nucleotides that corresponds with a specific amino acid or stop signal during protein synthesis. DNA and RNA molecules are written in a language of four nucleotides; meanwhile, the language of proteins includes 20 amino acids. Codons provide the key that allows these two languages to be translated into each other. Each codon corresponds to a single amino acid (or stop signal), and the full set of codons is called the genetic code. The genetic code includes 64 possible permutations, or combinations, of three-letter nucleotide sequences that can be made from the four nucleotides. Of the 64 codons, 61 represent amino acids, and three are stop signals. For example, the codon CAG represents the amino acid glutamine, and TAA is a stop codon. The genetic code is described as degenerate, or redundant, because a single amino acid may be coded for by more than one codon. When codons are read from the nucleotide sequence, they are read in succession and do not overlap with one another.

Credit : Scitable

Picture Credit : Google