Spirochetes
Spirochetes
Spirochetes are a group comprised of six genera of bacteria in a family known as Spirochaete. They are named because of their spiral shape. Typically, spirochetes are very slender. Their length can vary from about five microns (millionths of an inch) to several hundred microns, depending on the species. Under the light or electron microscope , the tight coiling that is characteristic of spirochetes is readily visible. Spirochetes are a significant health threat to humans. Both syphilis and Lyme disease are caused by spirochetes. Beneficially, spirochetes contribute to digestion in ruminants such as cows.
Besides their shape, another distinctive aspect of spirochetes in the presence of what is essentially internal flagella. These structures, called axial filaments, are embedded in the cell wall of the bacterium. They are constructed very similarly as flagella, having the characteristic arrangement of structures that anchors the filament to the cell membrane. There can be only a few to as many as 200 axial filaments present in a given bacterium. The rigidity of an axial filament allows a bacterium to move in a corkscrew type of motion. Axial filaments are present in all spirochetes except Treponema.
Spirochetes have varied habitats and growth requirements. Some of the bacteria require oxygen for their survival, while others do not tolerate the presence of oxygen.
In terms of human health, spirochetes are noteworthy because of the disease causing members of the group. Treponema pallidum is the cause of syphilis and Borrelia burgdorferi is the cause of Lyme disease, which can produce a chronic infection that can result in arthritis, damage to the central nervous system, and even heart failure. Borrelia burgdorferi can convert to a metabolically dormant cyst in natural environments and even in humans. The cyst form allows the bacterium to survive inhospitable conditions and to elude host immune defense mechanisms.
In ruminants, spirochetes are beneficial. Their chemical activities help the cow or other ruminant digest food. Spirochetes also live in harmony with mussels and oysters, where the bacteria help in feeding by acting as cilia to sweep food into the mollusk.
A spirochete known as Aquaspririllum magnetotacticum is of interest to microbiologists because it is one of a number of bacteria that possess magnetic particles. These particles allow a bacterium to orient itself in the water in relation to Earth's magnetic field.
See also Bacteria and bacterial infection; Bacterial movement; Magnetotactic bacteria
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George VI was flawed, yet dignified.(Arts)(Critic At Large)
Newspaper article from: The Washington Times; 10/26/1997; ; 700+ words
; ...should recall the dignity of King George VI. As Martin Sieff, State Department...what if he doesn't like it?" George VI perhaps understood the difficulties...by his bier. One author claimed George VI's genius was in convincing Britons...
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A Spirit Undaunted: The Political Role of George VI.(Review)
Magazine article from: Contemporary Review; 4/1/1999; ; 700+ words
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Was there a George VI style? Now that the story of British architecture and design in the twentieth century is less often distorted by over-emphasis on the modern movement, the variety and quality of what was produced can be appreciated afresh. Alan Powers argues that new stylistic terms are needed for mid-century design, among them the concept of a 'George VI style'.
Magazine article from: Apollo; 10/1/2004; ; 700+ words
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Comment: The King of appeasers Forget the Duke of Windsor, says John Charmley; a worse example was set by George VI and his Queen
Newspaper article from: The Sunday Telegraph London; 12/8/1996; ; 700+ words
; ...photograph of the Prime Minister and George VI together - loyal subject and loyal...on Nazi Germany and appeasement. George VI's ostentatious support for Chamberlain...doubt. George V, Edward VIII and George VI all deplored the prospect of another...
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King George VI suspected Blunt was Russian spy
Newspaper article from: The Sunday Telegraph London; 3/2/2003; ; 608 words
; ...historian Kenneth Rose discloses that George VI and his courtiers believed that Blunt...had proof of Blunt's treachery. George VI, however, allowed Blunt to continue...past." It is not known whether George VI shared his fears with post-war...
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Britain says proposal to place King George VI statue among Hong Kong zoo monkeys 'does seem a pity'
News Wire article from: AP Worldstream; 1/10/2003; ; 569 words
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Poetic reference to George VI
Newspaper article from: Belfast Telegraph; 4/9/2002; 428 words
; ...read to the nation by her husband George VI at the outbreak of war in 1939...also inscribed on the gates of the George VI Memorial Chapel in Windsor where...before she died. The poem was read by George VI in his 1939 Christmas Broadcast...
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A loss to remember before we rejoice in the Jubilee George VI founded the modern monarchy which we celebrate this year, says Andrew Roberts
Newspaper article from: The Sunday Telegraph London; 1/6/2002; ; 700+ words
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 "The Mirror (London, England)")
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Days out King George VI Chase: Still fragrant with Orchid's bloom.(Features)
Newspaper article from: The Mirror (London, England); 12/24/1998; ; 465 words
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Death of king George vi puts country in mourning
Newspaper article from: Lincolnshire Echo; 2/5/2008; 504 words
; ...1952, with the news that King George VI had died in his sleep. The sudden...Sandringham in his usual health. George VI had been catapulted on to the throne...Bar. After lying-in-state, George VI's funeral was held on February...
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George VI
Book article from: The Oxford Companion to British History
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Lévi, Éliphas (1810-1875)
Encyclopedia entry from: Encyclopedia of Occultism and Parapsychology
L é vi, É liphas (1810...named Ganneau. L é vi's pamphlet entitled The Gospel...xC9; liphas L é vi. Trans. Arthur Edward Waite...Arthur Edward Waite. London: George Redway, 1896. Reprint, New...
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James I and VI (England and Scotland) (1566–1625)
Encyclopedia entry from: Europe, 1450 to 1789: Encyclopedia of the Early Modern World
...x2013; 1625) JAMES I AND VI (ENGLAND AND SCOTLAND) (1566...1625) and Scotland (as James VI, 1567 – 1625). Born...month-old son was crowned James VI of Scotland. James's minority...tutors, the strict Calvinist George Buchanan and the more sympathetic...
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Henry VI, King, Parts 1, 2
Book article from: The Concise Oxford Companion to English Literature
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James VI
Book article from: A Dictionary of British History
James VI(1566–1625), king of Scotland...succession of formidable tutors, including George Buchanan , whose insistence that kings were...by appointing the low‐church George Abbot as archbishop. James also remained...
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