Sunday, August 28, 2011

Canada 2011 Canadian Innovation - The Pacemaker

The Canadian Post issued on 17 August 2011, a set of 4 stamps on the theme of Canadian innovations. One stamp, shown on the left, features the pacemaker, designed and built by Canadian electrical engineer John Hopps in 1950 based upon observations by cardio-thoracic surgeon Wilfred Gordon Bigelow at Toronto General Hospital. This initial is very big machine using vacuum tube technology to provide transcutaneous pacing for the heart, it was somewhat crude and painful to the patient in use and, being powered from an AC wall socket, carried a potential hazard of electrocution of the patient by inducing ventricular fibrillation.

The development of the silicon transistor and its first commercial availability in 1956 was the pivotal event which led to rapid development of practical cardiac pacemaking. In 1958, American engineer Earl Bakken of Minneapolis, Minnesota, produced the first wearable external pacemaker. This transistorised pacemaker, housed in a small plastic box, had controls to permit adjustment of pacing heart rate and output voltage and was connected to electrode leads which passed through the skin of the patient to terminate in electrodes attached to the surface of the myocardium of the heart. The first clinical implantation into a human of a fully implantable pacemaker was in 1958 at the Karolinska Institute in Solna, Sweden, using a pacemaker designed by Rune Elmqvist and surgeon Åke Senning, connected to electrodes attached to the myocardium of the heart by thoracotomy. The device failed after three hours. A second device was then implanted which lasted for two days. The world's first implantable pacemaker patient, Arne Larsson, went on to receive 26 different pacemakers during his lifetime. He died in 2001, at the age of 86, outliving the inventor as well as the surgeon.

Friday, August 19, 2011

Netherlands 2011 Utrecht University Biomedical Sciences

The Netherlands postal authority released a sheetlet of 10 stamps on 28 March 2011, celebrating the 375th Anniversary of Utrecht University, one of the top universities in Europe. Each of the 10 stamps celebrates an important Utrecht University event in these 375 years, this particular stamp illustrated with the double helix structure of DNA celebrates the 25th anniversary of the Utrecht University Biomedical Sciences Studies.

Thursday, July 21, 2011

Netherlands 2011 On microbiology

The Netherlands issued 10 nondenominated "1" stamps on 20 April 2011 to mark the 75th anniversary of the Netherlands Society for Microbiology. The various microscopic life forms harnessed by human featured on the stamps include yeast (Saccharomyces cerevisiae) for fermentation in wine production, lactic bacterium (Lactococcus lactis) for making cheese from milk, rhizobium that provides nitrogen for planting, Anammox (short for ANaerobic AMMonium OXidation) bacteria for rendering waste water harmless, bacteriophage that kills harmful bacteria, penicillium for production of penicillin, methonosarcina for production of methane gas (biogas), marine green algae, Tetraselmis suecica, for production of biodiesel, Aspergillus niger (black mold) for breaking down vegetable waste into compost, and bacillus bacteria that repairs concrete by filling up cracks with lime.

USA 2011 American Scientist: Dr Severo Ochoa

The US Postal Service released a third series of American Scientists stamps on 16 June 2011. The set comprises 4 stamps, and one of them features Dr Severo Ochoa. Ochoa was awarded the 1959 Nobel Prize for Physiology or Medicine for his work the synthesis of RNA.
Severo Ochoa was born on 24 September 1905 in Spain. Ochoa attended elementary school and high school in Malaga, then in 1923 he went the University of Madrid Medical School. He completed his undergraduate medical degree in summer of 1928 and developed an interest in going abroad to gain further research experience. His previous creatine and creatinine work led to an invitation to join Otto Meyerhof’s laboratory at the Kaiser Wilhelm Institute for Biology in Berlin-Dahlem in 1929. At that time the Institute was a "hot bed" of the rapidly evolving discipline of biochemistry, thus Ochoa had the experience of meeting and interacting with scientists such as Otto Warburg, Carl Neuberg, Einar Lundsgaard, and Fritz Lipmann in addition to Meyerhof who had received the Nobel Prize in Physiology and Medicine less than a decade earlier. In 1930 Ochoa returned to Madrid to complete research for his MD thesis, which he defended that year. In 1931, a newly minted MD, married Carmen García Cobián and began postdoctoral study at the London National Institute for Medical Research (NIMR), where he worked with Sir Henry Dale. With the outbreak of the Spanish civil war, Ochoa left Spain in 1936, taking up poistion in various parts of Europe. In 1942, Ochoa went to USA and started working for the New York University School of Medicine. He became an America citizen in 1956.
After receiving the Nobel Prize in 1959, Ochoa continued research on protein synthesis and replication of RNA viruses until 1985, when he returned to Spain and gave advice to Spanish science policy authorities and scientists. Ochoa was also a recipient of U.S. National Medal of Science in 1979. Severo Ochoa died in Madrid, Spain on 1st November 1993.
The 2011 American scientist stamp of Severo Ochoa is illustrated with photographs of Ochoa in his laboratory in 1959; Ochoa’s signature, from a 1949 letter to colleague Arthur Kornberg; a scheme, from one of his publications, representing the replication of viral RNA; and an equation representing the bacterial ribosome cycle in polypeptide synthesis. Severo Ochoa is also featured in the 2003 (20 March) Spain-Sweden joint stamp issue for recipients of Nobel Prize for Physiology or Medicine.

Saturday, July 2, 2011

30th Anniversary of Identification of AIDS

The year 2011 marks the 30th anniversary of the HIV virus discovery and, at the same time, 30 years of fight against this global plague. Between 8 and 10 June, the activities of the UN General Assembly High Level Meeting on fight against HIV/AIDS will be conducted at the UN Headquarters in New York. Romania issued a commemorative stamp on 8 June for this event, featuring the red ribbon signifying the fight against AIDS, and the representative structure of the AIDS virus.
As shown on the stamp, the AIDS virus structure is roughly spherical with a diameter of about 120 nm. It is composed of two copies of positive single-stranded RNA that codes for the virus's nine genes enclosed by a conical capsid composed of 2,000 copies of the viral protein p24. The single-stranded RNA is tightly bound to nucleocapsid proteins, p7, and enzymes needed for the development of the virion such as reverse transcriptase, proteases, ribonuclease and integrase. A matrix composed of the viral protein p17 surrounds the capsid ensuring the integrity of the virion particle. This is, in turn, surrounded by the viral envelope that is composed of two layers of fatty molecules called phospholipids. Embedded in the viral envelope are proteins from the host cell and about 70 copies of a complex HIV protein that protrudes through the surface of the virus particle. This protein, known as Env, consists of a cap made of three molecules called glycoprotein (gp) 120, and a stem consisting of three gp41 molecules that anchor the structure into the viral envelope. This glycoprotein complex enables the virus to attach to and fuse with target cells to initiate the infectious cycle.
The Serbian Post released on 1 June the commemorative stamp with an artist's impression of the virus, with the external glycoprotein structures shown.

Thursday, June 9, 2011

Mozambique 2010 A Tribute to Marshall Warren Nirenberg

Marshall Warren Nirenberg was awarded the Nobel Prize in Physiology or Medicine in 1968 for deciphering the genetic code. It was during his early post-doctoral days at the National Institute of Health (NIH) that he conducted a series of experiments leading to the discovery of how the triplets of nucleotides combined to form the different amino acids necessary for protein synthesis. He discovered first the codon for phenylalanine, he then presented his work in 1961 at the International Congress of Biochemistry at Moscow, receiving scant attention, until Francis Crick organised a repetition of the presentation in a larger hall in the same Congress. By 1966 Nirenberg had worked out the codons for all the 20 amino acids; in 1968 he received the Nobel Prize. All this time, Severo Ochoa, already a Nobel laureate, was pursuing for the same results in a large lab at New York University; in view of this stiff competition, all of Nirenberg's colleagues and friends at NIH dropped their own work to help him succeed in the race to decipher the complete codon table. Marshall Warren Nirenberg died of cancer on 15 January 2010, at the age of 82.
The mushrooms featured on the souvenir sheets and the stamps themselves have no links to Marshall Warren Nirenberg, they are included by the printers of these souvenir sheets targetted at philatelic enthusiasts.

Sunday, May 15, 2011

Romania 2011 World Down Syndrome Day

Romania has released on 21 March 2011 a stamp marking World Down Syndrome Day. Down Syndrome is a genetic disorder that occurs in approximately 1 out of 800 live births. First described by British physician John Langdon Down in 1866, it is the leading cause of cognitive impairment. On 21st of March 2006, Down Syndrome Association organized, in Singapore, the first actions meant to draw attention to the appropriate understanding of this condition. Simultaneously, similar events occurred in Geneva. Later, March 21st was declared the World Down Syndrome Day. This date is symbolic as Down Syndrome is also known as Trisomy 21 - Down Syndrome babies have 3 copies of chromosome 21.