2 Perhaps his most famous microscopical observation was his study of thin slices of cork. He wrote: . . . I could exceedingly plainly perceive it to be all perforated and porous. . . these pores, or cells, . . . were indeed the first microscopical pores I ever saw, and perhaps, that were ever seen, for I had not met with any Writer or Person, that had made any mention of them before this
4 Pioneer microbiologist, was born in Delft, Holland and learned the art of making lenses in Amsterdam. On his return to Delft in 1652, he developed an interest in microscopy. He announced the discovery of protozoa in 1677 in the Philosophical Transactions. He was the first to distinguish bacteria and he published his drawings in the same journal in 1683. He is esteemed as the first protozoologist and bacteriologist. He also observed canals in bone in 1675,later called the Haversian canals. Following his death, his 248 microscopes were auctioned by his daughter Maria&quot; (A Dictionary of the History of Medicine, Anton Sebastian).
7 He read in the book on generation by William Harvey a speculation that vermin such as insects, worms, and frogs do not arise spontaneously, as was then commonly believed, but from seeds or eggs too small to be seen. In 1668, in one of the first examples of a biological experiment with proper controls, Redi set up a series of flasks containing different meats, half of the flasks sealed, half open. He then repeated the experiment but, instead of sealing the flasks, covered half of them with gauze so that air could enter. Although the meat in all of the flasks putrefied, he found that only in the open and uncovered flasks, which flies had entered freely, did the meat contain maggots. Though correctly concluding that the maggots came from eggs laid on the meat by flies, Redi, surprisingly, still believed that the process of spontaneous generation applied in such cases as gall flies and intestinal worms. Redi is known as a poet chiefly for his Bacco in Toscana (1685; &quot;Bacchus in Tuscany&quot;).
Redi, Francesco b. Feb. 19, 1626, Arezzo, Italy d. March 1, 1697, Pisa Italian physician and poet who demonstrated that the presence of maggots in putrefying meat does not result from spontaneous generation but from eggs laid on the meat by flies. He read in the book on generation by William Harvey a speculation that vermin such as insects, worms, and frogs do not arise spontaneously, as was then commonly believed, but from seeds or eggs too small to be seen. In 1668, in one of the first examples of a biological experiment with proper controls, Redi set up a series of flasks containing different meats, half of the flasks sealed, half open. He then repeated the experiment but, instead of sealing the flasks, covered half of them with gauze so that air could enter. Although the meat in all of the flasks putrefied, he found that only in the open and uncovered flasks, which flies had entered freely, did the meat contain maggots. Though correctly concluding that the maggots came from eggs laid on the meat by flies, Redi , surprisingly, still believed that the process of spontaneous generation applied in such cases as gall flies and intestinal worms. Redi is known as a poet chiefly for his Bacco in Toscana (1685; &quot;Bacchus in Tuscany&quot;).
8 Needham, John Turberville (b. Sept. 10, 1713, London--d. Dec. 30, 1781, Brussels), English naturalist and Roman Catholic divine, first clergyman of his faith to become a member of the Royal Society of London (1768). He was ordained in 1738 but spent much of his time as a teacher and tutor. His reading about animalcules (microscopic organisms) aroused an interest in natural science, and from 1746 to 1749 he studied in that field in London and Paris. He became a staunch advocate of the theories of spontaneous generation (life from inorganic matter) and vitalism (doctrine holding that life processes cannot be explained by the laws of chemistry and physics). In 1750 he presented a paper explaining the theory of spontaneous generation and attempting to offer scientific evidence supporting the theory. In 1767 he retired to the English seminary at Paris to pursue his scientific experiments. He also served as the director of the Imperial Academy in Brussels until 1780. John Turberville Needham John Turberville Needham, 1713 - 1781 , English scientist and Catholic priest. Needham's Observations upon the Generation, Composition, and Decomposition of Animal and Vegetable Substances ( 1748 ) offered what he considered to be proof of spontaneous generation. His claim that sealed flasks of broth produced animalcules even after the broth had been boiled suggested the microbes had developed from inanimate matter, although his experimental techniques were apparently faulty. Three years after this publication, Maupertuis challenged his findings in his Système de la nature .
9 Spallanzani, Lazzaro b. Jan. 12, 1729, Modena, Duchy of Modena d. 1799, Pavia, Cisalpine Republic Italian physiologist who made important contributions to the experimental study of bodily functions and animal reproduction. His investigations into the development of microscopic life in nutrient culture solutions paved the way for the research of Louis Pasteur. Spallanzani was the son of a distinguished lawyer. He attended the Jesuit college at Reggio, where he received a sound education in the classics and philosophy. He was invited to join the order, but, although he was eventually ordained (in 1757), he declined this offer and went to Bologna to study law. Under the influence of his kinswoman Laura Bassi, a professor of mathematics, he became interested in science. In 1754 Spallanzani was appointed professor of logic, metaphysics, and Greek at Reggio College and in 1760 professor of physics at the University of Modena. Although Spallanzani published in 1760 an article critical of a new translation of the Iliad, all of his leisure was being devoted to scientific research. In 1766 he published a monograph on the mechanics of stones that bounce when thrown obliquely across water. His first biological work, published in 1767, was an attack on the biological theory suggested by Georges Buffon and John Turberville Needham, who believed that all living things contain, in addition to inanimate matter, special &quot;vital atoms&quot; that are responsible for all physiological activities. They postulated that, after death, the &quot;vital atoms&quot; escape into the soil and are again taken up by plants. The two men claimed that the small moving objects seen in pond water and in infusions of plant and animal matter are not living organisms but merely &quot;vital atoms&quot; escaping from the organic material. Spallanzani studied various forms of microscopic life and confirmed the view of Antonie van Leeuwenhoek that such forms are living organisms. In a series of experiments he showed that gravy, when boiled, did not produce these forms if placed in phials that were immediately sealed by fusing the glass. As a result of this work, he concluded that the objects in pond water and other preparations were living organisms introduced from the air and that Buffon's views were without foundation. ( See spontaneous generation.) Lazzaro Spallanzani Lazzaro Spallanzani, 1729 - 1799 , Italian biologist. Spallanzani did extensive research on the reproduction of animals, and definitively disproved the theory of spontaneous generation ( 1768 ). In 1779 he discovered the workings of animal reproduction, which requires semen (carrying spermatazoa) and an ovum. In 1780 he applied this discovery and performed the first artificial insemination (of a dog).
16 Smallpox and Inoculation The incidence of smallpox in Britain reached its peak in the eighteenth century. Although there were outbreaks all over the country, it was in London that the disease showed such a constant prevalence. In the 80 years between 1721 and 1800 the annual deaths from smallpox in the Metropolis were less than 1,000 in only 5 individual years. In 1772 it caused 3,992 deaths in London. But the pock-marked faces of so many dwellers in the great city bore striking witness to the prevalence of the disease-in contradistinction to its mortality. The practice of inoculation for preventive purposes was well recognised during the second half of the eighteenth century. The &quot;prevention&quot; desired was of course that from death, and not from the disease, which was transmitted during the operation to the individual to be inoculated. Inoculated smallpox was often fairly mild, and the theory was that it was better to obtain protection as a result of a mild attack at a convenient time than to risk a severe and possibly fatal attack when one wanted it least. Practised in the East from ancient times, inoculation was introduced into this country by Timoni (1714) and by Pylarini, and a renewed effort to popularise it was made by Lady Mary Wortley Montagu (1721), who had just returned from seeing it performed in Constantinople, and had her son inoculated. After 1738 the practice increased, but nothing could get over the fact that the inoculated disease was often not mild and deaths were not infrequent. There were also other frequent side effects, causing serious damage, for example, to the heart, brain, eyes and other organs, even if not immediately proving fatal. In 1840 the practice of inoculation became illegal. The Beginnings of Vaccination While he was an apprentice at Sodbury Jenner was struck by the fact that a young countrywoman had said that she could not take smallpox because she had had cowpox. He mentioned this curious statement to John Hunter, but the latter was apparently not interested. Years later Jenner began to collect examples of persons whom he could not inoculate successfully because they had had cowpox at some time during the course of their lives. Even at this early stage he seems to have been obsessed by the feeling that cowpox ought to give complete and permanent immunity to smallpox. This is indeed strange, since every practitioner knew that smallpox did not always give complete and permanent protection against itself. By this time John Hunter was dead, and there was no one of his experience and acuteness with whom Jenner could discuss the matter. Jenner therefore set out to show that cowpox protected against smallpox, and also that cowpox could be transmitted from one human being to another just as smallpox could. There should be no misconception of what was in Jenner's mind. Though his arguments and deductions are possibly not too well expressed, his line of thought clearly was constructive and of considerable originality. It was one thing to show that a person who had had a natural attack of cowpox was thereafter possessed of considerable immunity to smallpox. Cowpox was a disease of cows, and only a fraction of the population ever has any direct contact with these animals. Furthermore, cowpox was present only in certain counties of England, and only at intervals. It was quite another thing to set out deliberately with the intention of showing that cowpox, naturally acquired, could be transmitted artificially from person to person so that there would result an increasing reservoir of persons who had been given the opportunity of becoming invulnerable - or &quot;immune&quot;, as we would say - to smallpox. There is no doubt that this was what was in Jenner's mind. At a later date opponents of his views put forward counterclaims to priority. For example, there was the case of Benjamin Jesty, a farmer who twenty years before had inoculated his wife and children with cowpox to prevent them from contracting smallpox. But Jesty had no notion of perpetuating the cowpox from one individual to another. This was the cardinal factor in Jenner's doctrine, and it was an idea which had probably not occurred seriously to anyone before; at least, no one had ever attempted to put it into practice. Once this point is clearly grasped certain interesting questions arise. To show the pitfalls in Jenner's path it is sufficient to take one example. Only a few months after the publication of his famous book Jenner sent to a friend in London some lymph from the cowpox vesicle on a child's arm. The lymph was dried and preserved in a quill. Before long people were discussing the methods of transmitting lymph to a distance - dried on lancets and in other ways. If lymph from the human pock could be stored and transmitted in this way, why could not lymph from the pock on the cow? After all, this is essentially the method that we use today. The answer appears to be that Jenner was impressed early in his investigations by the fact that there are two types of cowpox in the cow - the true disease and another form which he called &quot;spurious cowpox&quot;. We now know that this view is wrong: but Jenner believed it, and he also believed that the spurious type does not give immunity in smallpox. On the other hand, true cowpox in the human bred true. He was therefore afraid that if the practice of using dried lymph from cows was widely adopted numerous failures might result. There was also the possibility that septic diseases might be transmitted or that the lymph might be taken at the wrong time. Difficulties of this type must have caused Jenner much reflection, and are ignored by many who are wise one hundred and fifty years after the event. The Inquiry In May, 1796, Jenner found that the dairymaid Sarah Nelrnes had a &quot;typical&quot; cowpox lesion on her finger, and on the fourteenth of that month he inoculated the boy James Phipps with the matter from that lesion. The local result was similar to that following variolous inoculation. On July 1st Jenner inoculated the boy with matter from a case of smallpox. The inoculation was unsuccessful. Jenner drew up in 1797 a short treatise embodying his results, and it was presented unofficially to the President of the Royal Society (Sir Joseph Banks). Two manuscripts of the first draft are in existence one in the Royal College of Surgeons and the other in the Wellcome Institute. The paper was refused. In the following spring Jenner added further material and published the work privately in July 1798. The book bears the title: An Inquiry into the Causes and effects of the Variolae Vaccinae, a disease discovered in some of the Western Counties of England particularly Gloucestershire, and known by the name of the Cow Pox. A second edition was published in 1800 and a third in 1801. The work was also translated into many languages. After the publication of this work Jenner spent three months in London looking for volunteers for vaccination. In this he was quite unsuccessful. But he left in the hands of Henry Cline, the surgeon, the quill of dried lymph referred to above. Cline used it as a measure of counter-irritation in a case of hip-disease, and found that the patient had become immune to inoculated smallpox. From this case the practice of vaccination began to spread. Very soon a difficulty arose, since Dr. Woodville had been distributing lymph derived from vaccinations carried out in the smallpox hospital, and not unnaturally it produced mild smallpox eruptions. Dr. Pearson, a fashionable physician, had taken up vaccination enthusiastically, and in 1800 he proposed to establish an institution for gratuitous vaccination. Jenner was offered the post of &quot;Extra Consulting Physician&quot;. From this and other incidents it was apparent that Pearson was trying to filch from Jenner the credit for the discovery. But events such as these could not rob him of the many honours which soon came to him, and which he received modestly but with due appreciation. Jenner spent some time in London in 1800, and he was then requested to vaccinate the 85th Regiment, which he did personally. About the same time the practice spread to the United States, where Professor Benjamin Waterhouse was largely instrumental in obtaining results. France, Spain, and the Mediterranean countries soon followed.
17 Focusing on a cure for the syphilis bacteria, Ehrlich began experimenting with various dyes, theorizing that dyes that did not color the bacteria had combined with it, and that by finding the right dye that eliminated the bacteria, (but not the other cells) the disease could be treated. With the help of his assistants, Ehrlich would prepare various dyes to be tested on animals. After 7 years and 605 created dyes, salvarsan, or Preparation 606, was the one dye that proved successful in the treatment of lab animals and humans. This breakthrough in chemotherapy awarded Ehrlich the Nobel Prize of 1908 [with Russian bacteriologist Elie Metchnikoff] and several other honors. However, success did not go to his head; he continued further research on salvarsan and distributed thousands of free doses to doctors around the world. His contributions to the discoveries and advances in immunology have been extremely helpful. His ideas in bacteriology and chemotherapy became a basis for many other diseases and medical research.
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16 Black Bread Mold This black bread mold growing on a piece of stale bread shows the mycelium, or interwoven filaments that make up the vegetative portion of the fungus. The small dark spots are the fruiting bodies, or sporangia, from which the spores are released. John Cooke, Oxford Scientific Films
18 Bread Yeast Bread yeast, or baker’s yeast, actually a type of sac fungi, reproduces by a process called budding. Bread yeast causes bread to rise by releasing carbon dioxide, which gets trapped in the dough. The Egyptians were the first to discover that allowing dough to ferment produced gases that made bread lighter. Safra Nimrod/Phototake NYC MichaelA. McClure PHD/Phototake NYC
Pure Culture Key to Studying Microbes Definition : Pure culture is a population of organism, all of which are the progeny of a single organism -In nature, microbes almost never occur as pure cultures
Was convinced that nasal mucus had antibacterial effects
Left his Staphylococcus culture on an agar plate for 2 weeks-went on vacation-came back &found mold on his plate which prevented bacterial growth (a mycology lab underneath him had this rare spore drift)