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765 [1216] MÜLLER
THEILER [1217] yet would have little or no poisonous effect on plants or on mammals, and would be cheap, stable, and without un pleasant odor. To be sure, there were a number of in secticides already on the market; but some were arsenic compounds that were dangerous to all forms of life and that accumulated (dangerously) in the soil. Others, less deadly to vertebrates, were also not very deadly to insects. It did not seem at all likely that Müller would find the combination of properties for which he was seeking, but if he did the value to agriculture would be inestimable. In his search Müller concentrated on certain types of chlorine-containing com pounds, for some examples of these types seemed to show promise. In Sep tember 1939, the month World War II broke out, Müller tried dichlorodiphenyl- trichloroethane (DDT is the common abbreviation), a compound that had first been synthesized in 1873. It worked! Switzerland put it to use at once in fighting the Colorado potato beetle. In 1942 it began to be produced commer cially in the United States and the next year it had its first important use in con nection, directly, with human beings. In late 1943, soon after it had been cap tured by Anglo-American forces, Naples had a typhus epidemic. Typhus epi demics had altered the course of World War I on the Russian and Balkan fronts, and it might well have done so again in World War II by stopping the Allied offensive in Italy faster than Nazi guns. However, Nicolle [956] had shown that typhus was contagious only through the transmitting bite of the body louse and in January 1944 DDT was brought into play against the creature. The popu lation of Naples was sprayed en masse and the lice died. For the first time in history, a winter epidemic of typhus (when the multiplicity of clothes, not re moved very often, made louse infestation almost certain and almost universal) was stopped in its tracks. A similar epidemic was stopped in Japan in late 1945 after the American occupation. Müller received the 1948 Nobel Prize in medicine and physiology for his dis covery.
With the end of the war, DDT came into use for agricultural purposes. Insect raids upon man’s food (or potential food) were decreased. Unfortunately, DDT-resistant strains of insects rapidly made their appearance, but to counter that, other insecticides were synthesized. The battle is by no means an easy one, but where insecticides are used intelli gently and with caution, the insect men ace is under far better control than ever before. However, it is also possible to use insecticides unwisely, with conse quent damage to desirable species of ani mals and, for that matter, even to man. Within a quarter century of its first great victories, therefore, DDT was being gravely studied as a possible seri ous pollutant of the environment. Its use was restricted or banned in various places and anxious looks are being turned on the study of ecology (the in terrelationship of forms of life with each other and with the inanimate environ ment) and the effect upon it of man’s chemical ingenuity and carelessness. [1217] THEILER, Max (ty'ler) South African-American micro biologist
January 30, 1899 Died: New Haven, Connecticut, August 11, 1972 Theiler attended the University of Capetown, but in 1920, midway in his studies, he persuaded his father (a Swiss- born veterinarian) to send him to Lon don. There he found he would have to start his college courses over again and rather than do that he spent four years in a hospital, absorbing practical instruc tion. In 1922 Theiler arrived in the United States, having accepted a post at the Harvard University Medical School. He transferred to the Rockefeller Founda tion in New York in 1930. In the 1920s Theiler began research on yellow fever. Reed [822] had con quered it in one way by showing that wiping out the appropriate mosquito pre vented its being transmitted. This, how 7 6 6
[1218] BEST
BEKESY [1220] ever, was only second best, for it was impractical to expect to wipe out all the mosquitoes. Artificially acquired immu nity by vaccination, after the methods of Jenner [348] and Pasteur [642], would be better. To work out some sort of vaccine, Theiler had to cultivate the yellow fever virus. He found that he could infect monkeys with yellow fever, then pass the virus into mice. In mice, it developed as encephalitis, a brain inflammation. He could pass the virus from mouse to mouse and then, eventually, back to monkeys. But then it was an attenuated virus, producing only the feeblest yellow fever attack but inducing full immunity to the most virulent strains of the virus. He used himself and his colleagues as guinea pigs to test its protective qualities against such full-strength virus. This vaccine was much used by the French in Africa during the 1930s and 1940s. A still safer vaccine, produced by selecting nonvirulent strains of virus from among those passed along from chick embryo to chick embryo in nearly two hundred transplants, was prepared in 1937. This second vaccine became standard in South America. For this work, Theiler, still without ac ademic degrees, was awarded the 1951 Nobel Prize in medicine and physiology. In 1964 he accepted a post as profes sor of microbiology at Yale University and held that till his retirement in 1967. [1218] BEST, Charles Herbert American-Canadian physiologist
February 27, 1899 Died: Toronto, Ontario, March 31, 1978 Best, the son of a Canadian-born phy sician, attended the University of To ronto, graduating in 1921 after taking time out to serve in the Canadian artil lery during World War I. (He qualified for Canadian citizenship by so doing.) He then went on to medical studies. It was as a medical student that he put in a summer with Banting [1152] and helped isolate insulin. His motivation, in part, arose from the fact that a favorite aunt of his had recently died of diabetes. He obtained his medical degree in 1925, and although he had missed out on a share of the Nobel Prize (to Ban ting’s great indignation) he has received his fair share of the acclaim. He remained connected with the Uni versity of Toronto, directed the Banting- Best Department of Medicine Research after Banting’s death, and became the head of the physiology department in 1929. He did work on the anti-allergic enzyme histaminase, and on the blood clotting agent heparin. With Norman B. Taylor, he wrote a best-selling textbook on physiology, which went through eight editions in his lifetime. [1219] VAN VLECK, John Hasbrouck American physicist
March 13, 1899 Died: Cambridge, Massachusetts, October 27, 1980 Van Vleck graduated from the Univer sity of Wisconsin in 1920 and obtained his Ph.D. at Harvard in 1922. He taught at Harvard, the University of Minnesota, and the University of Wisconsin. He re turned to Harvard in 1934 and remained there thereafter. His chief field of research lay in the magnetic properties of individual atoms, based on a quantum mechanical consid eration of the electronic distribution within the atom. During the 1930s he evolved a theory that took into account the influence on each electron of neigh boring electrons. It is still the dominating theory in the field and for it he obtained a share of the 1977 Nobel Prize for physics.
[1220] BEKESY, Georg von Hungarian-American physicist Born: Budapest, Hungary, June 3, 1899
Died: Hawaii, June 13, 1972 Bekesy, the son of a diplomat, studied at the University of Bern in Switzerland,
[1220] BÉKÉSY
LIPMANN [1221] graduating in 1920. He went on to fur ther studies at the University of Bu dapest, gaining his doctorate in 1923. He then worked for the Hungarian tele phone system for nearly a quarter of a century thereafter, doing research in acoustics. He served also on the faculty of the University of Budapest. His work went on undisturbed by World War II, but at its close, with So viet forces occupying the land, he no longer thought it wise to remain in Hun gary. He left in 1946 for Sweden, then in 1947 went to the United States. After his arrival he worked at Harvard University and then, in 1966, accepted a professorial position at the University of Hawaii. He devised an audiometer to test the hearing function. In addition, he sug gested a theory of hearing to replace one first proposed by Helmholtz [631]. The immediate organ of hearing is contained in a spiral tube called the cochlea, located in the inner ear. It is divided into two sections by a basilar membrane. The basilar membrane is made up of some 24,000 parallel fibers stretched across its width. These fibers are progres sively wider as one moves along the cochlea to its tip. Helmholtz had thought that each fiber had its natural period of vibration and responded to a sound that vibrated in that natural period. Every ordinary sound is made up of a combination of pure vibrations and such a sound sets up vibrations in a combination of fibers. The nerve messages sent by the various vibrating fibers would then be combined and interpreted by the brain as a sound of a particular pitch, loudness, and qual ity. Bekesy, however, conducted careful experiments with an artificial system de signed to mimic all the essentials of the cochlea and found that sound waves passing through the fluid in the cochlea set up wavelike displacements in the bas ilar membrane. It is the shape of the wave, varying with pitch, loudness, and quality that gives the brain the material to work with. As a result, Bekesy was awarded the 1961 Nobel Prize in medicine and physi ology, the first physicist ever to win the prize in this category. [1221] LIPMANN, Fritz Albert German-American biochemist
(now Kaliningrad, Soviet Union), June 12, 1899 After studying at the universities of Königsberg and of Munich, Lipmann ob tained his medical degree at the Univer sity of Berlin in 1922 and his Ph.D. there in 1927. He spent three years thereafter in Meyerhof’s [1095] labora tory in Heidelberg and a year with Le vene [980] in New York. The growth of the Nazi movement made life in Germany increasingly un comfortable for him and in 1932 he transferred the scene of his labors to Copenhagen, Denmark. In 1939 he emi grated to the United States and became an American citizen in 1944. He worked for two years with Du Vigneaud [1239] at Cornell, then served on the staff of the Massachusetts General Hospital through 1957, after which he joined the Rocke feller Institute for Medical Research (now Rockefeller University) in New York. Lipmann rationalized the role of phos phate esters in carbohydrate metabolism. The existence of these esters had first been noted by Harden [947] and had been worked out in greater detail by Meyerhof and by the Coris [1192, 1194], but in 1941 Lipmann supplied a vital point. He noted that phosphate esters, on breaking down and losing their phos phate group, might yield a relatively small amount of energy (low-energy phosphate) or a considerably higher amount (high-energy phosphate). He was able to distinguish the characteristic structures of each variety. He went on to show that the course of carbohydrate metabolism involved the fixing of phosphate groups onto organic molecules in low-energy configuration, followed by changes in the molecule that would convert it into a high-energy configuration. The high-energy config 7 6 8
[1222] CLAUDE
BURNET [1223] uration would then serve as the “small change” energy bits utilized by the body. This concept has been strengthened in the decades since. The energy content of the various foodstuffs, as molecules are broken down, is pumped into phosphate- containing compounds, changing the low-energy configuration into the high- energy. TTie most versatile of the high- energy configurations is a compound called adenosine triphosphate, usually re ferred to as ATP, which has been found to be concerned with body chemistry at almost every point where energy is re quired.
In 1947 Lipmann discovered a com pound that controlled the transfer of two-carbon groups from one molecule to another. He called it coenzyme A and showed that the B vitamin known as pantothenic acid (first discovered in 1933, with a structure first worked out in 1940) made up part of the molecule. In fact, pantothenic acid in small quanti ties is essential to life, precisely because it forms part of coenzyme A. The work of Krebs [1231] had shown that lactic acid was broken down to car bon dioxide and water by way of a two- carbon compound that entered what came to be known as the Krebs cycle. Lipmann thought it quite likely that this two-carbon compound entered the cycle with the help of coenzyme A and by 1951 was able to demonstrate this. The two-carbon compound combined with coenzyme A, in fact, to form acetylcoen- zyme A. Acetylcoenzyme A turned out to be a veritable crossroads of body chemistry. Carbohydrates, fats, and most portions of the protein molecule had to pass through it in order to be broken down for energy purposes and it was through acetylcoenzyme A that carbohydrate, for instance, could be converted into fat. For his work on coenzyme A, Lip mann shared the 1953 Nobel Prize in medicine and physiology with Krebs. [1222] CLAUDE, Albert Belgian-American cytologist Born: Longlier, Belgium, August 24, 1898 Claude received his M.D. from the University of Liège in 1928. He then went on to work at the Rockefeller Insti tute (now Rockefeller University) in New York and became an American citi zen in 1941. He pioneered the use of the electron microscope in the study of cells and by 1945 had produced the first studies of the intimate anatomy of the cell on a finer scale than would have been thought possible a decade before. He probed the mitochondria and discovered the en doplasmic reticulum, which serves as the structural background of the cell, hold ing the organelles in place. For this he shared the 1974 Nobel Prize for physiology and medicine with Palade [1380] and De Duve [1418]. [1223] BURNET, Sir Frank Macfarlane Australian physician
tember 3, 1899 Burnet was educated at Geelong Col lege in Victoria and obtained his medical degree in 1923 at the University of Mel bourne. He did further work in England at the University of London, where he obtained his Ph.D. in 1927. He then re turned to Australia, working at the Walter and Eliza Hill Institute for Medi cal Research in Melbourne, and after 1944 serving as professor of experi mental medicine at the University of Melbourne. Burnet’s great concern was virus dis eases, and through this he began to con sider the mechanism of immunity. Im munity results from the formation of an tibodies in response to some foreign sub stance, usually a protein. The antibody, by combining with the protein, vitiates its harmful effects. The protein eliciting the formation of an antibody may be part of a microorganism or not. It may be a food component or a tissue graft. Where antibodies are formed against es sentially harmless proteins in food or other materials (producing distressing symptoms in the process) the process is described as an allergy. The proteins of every human being 7 6 9
[1224] DOBZHANSKY RICKOVER
(identical twins excepted) are strange to every other human being. If skin, or some internal organ, is grafted from one person to another, the receiving person produces antibodies that combine with the graft and prevent it from “taking.” Surgical procedures that could be very helpful, even life-saving, to a patient are thus brought to nothing by the patient’s own chemical mechanisms. It seemed to Burnet that the ability of a human being to form antibodies against the proteins of another human being might not be inborn. Antibodies against disease develop only after expo sure to the microorganisms causing the disease. Allergies develop only after sen sitization to a particular protein. Should not resistance to the proteins of another individual likewise be developed only in the course of life; perhaps very early in life, to be sure; in the embryonic stage, for instance? Burnet made this suggestion in 1949 and the idea was acted on, with success, by Medawar [1396]. For this Burnet was knighted in 1951, and he and Medawar shared the 1960 Nobel Prize in medicine and physiology. Burnet’s suggestion was more pointed than ever when it was discovered in 1961 that the ability to form antibodies lodged with the thymus gland at birth and was not distributed through the tis sues until some time after birth. [1224] DOBZHANSKY, Theodosius Russian-American geneticist Born: Nemirov, Ukraine, January 25, 1900 Died: Davis, California, Decem ber 18, 1975 Dobzhansky, the son of a teacher of mathematics, entered the University of Kiev in 1917 and remained firmly at his studies during the chaos of the Russian Revolution and the civil war, graduating in 1921. He taught at Kiev, then moved on to Leningrad. In 1927 Dobzhansky went to Columbia University to work with T. H. Morgan [957] and went with him to the Califor nia Institute of Technology. He obtained a teaching position there and became a U.S. citizen in 1937. He returned to Co lumbia in 1940, accepted a position at the Rockefeller Institute (now Rocke feller University) in 1962, and, after his retirement in 1971, moved on to the University of California at Davis. Since the rediscovery of Mendelian ge netics by De Vries [792] and others in 1900, geneticists had been trying to fuse genetics with Darwin’s [554] evolution by natural selection. The assumption had been that there were normal genes and periodic mutations (which were mostly deleterious and quickly weeded out), with the very occasional beneficial muta tion serving to produce an evolutionary change. Dobzhansky showed this was not so and in 1937 published a book entitled Genetics and the Origin of Species, in which Mendel and Darwin were neatly put together. Dobzhansky showed that mutations were common and were fre quently viable so that there was no such thing as a “normal” gene, merely different varieties that all maintained themselves in varying amounts depend ing on chance and on local conditions. Natural selection had a great deal to work on, but the work was complex and anything but clearcut. Dobzhansky also worked on the man ner in which new species formed and on the manner in which humankind had evolved.
[1225] RICKOVER, Hyman George Polish-American naval officer Born: Makov, Poland (then part of Russia), January 27, 1900 Rickover was taken to the United States in 1904. His education was cli maxed by graduation from the U. S. Naval Academy in 1922. He became a qualified submariner in 1930 and then studied engineering at Columbia Univer sity, earning his master’s degree. In 1946 Rickover (then a captain), with some other officers, went to Oak Ridge, Tennessee, to investigate the pos sibility of adapting a nuclear reactor to power production on naval vessels. Download 17.33 Mb. Do'stlaringiz bilan baham: |
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