ESCHERICHIA
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ESCHERICHIA
Superdomain: Phylogenetica Phylum: Proteobacteria Class: Gamma Proteobacteria Order: Enterobacteriales Family: Enterobacteriaceae Genus: Escherichia Species: E. coli
Escherichia coli (E. coli), is one of many species of bacteria living in the lower intestines of mammals, known as gut flora. When located in the large intestine, it assists with waste processing, vitamin K production, and food absorption. Discovered in 1885 by Theodor Escherich, a German pediatrician and bacteriologist, E. coli are abundant: the number of individual E. coli bacteria in the feces that a human defecates in one day averages between 100 billion and 10 trillion.[citation needed] However, the bacteria are not confined to this environment, and specimens have also been located, for example, on the edge of hot springs. The E. coli strain O157:H7 is one of hundreds of strains of the bacterium that causes illness in humans.
As with all Gram-negative organisms, E. coli are unable to sporulate. Thus, treatments which kill all active bacteria, such as pasteurization or simple boiling, are effective for their eradication, without requiring the more rigorous sterilization which also deactivates spores.
As a result of their adaptation to mammalian intestines, E. coli grow best in vivo or at the higher temperatures characteristic of such an environment, rather than the cooler temperatures found in soil and other environments.
E. coli can generally cause several intestinal and extra-intestinal infections such as urinary tract infections, meningitis, peritonitis, mastitis, septicemia and Gram-negative pneumonia. The enteric E. coli are divided on the basis of virulence properties into enterotoxigenic
Urinary tract infections
It is much more common in females due to the shorter urethra (25–50 mm / 1-2 inches) compared to males (about 20 cm / 8 inches). Among the elderly UTI is in roughly equal proportions in men and women. Since bacteria invariably enter the urinary tract through the urethra (an ascending infection), poor toilet habits can predispose to infection (doctors often advise women to "wipe front to back, not back to front") but other factors are also important: (pregnancy in women, prostate enlargement in men) and in many cases the initiating event is unclear. While ascending infections are generally the rule for lower urinary tract infections and cystitis, the same may not necessarily be true for upper urinary tract infections like pyelonephritis which may be hematogenous in origin. Most cases of lower urinary tract infections in females are benign and do not need exhaustive laboratory work-ups. However, UTI in young infants must receive some imaging study, typically a retrograde urethrogram, to ascertain the presence/absence of congenital urinary tract anomalies. Males too must be investigated further. Specific methods of investigation include x-ray, MRI and CAT scan technology.
Gastrointestinal
Low-temperature electron micrograph of a cluster of E. coli bacteria, magnified 10,000 times. Each individual bacterium is oblong shaped.
If E. coli bacteria escape the intestinal tract through a perforation (hole or tear, for example from an ulcer, a ruptured appendix, or a surgical error) and enter the abdomen, they usually cause peritonitis that can be fatal without prompt treatment. However, E. coli are extremely sensitive to such antibiotics as streptomycin or gentamycin, so treatment with antibiotics is usually effective. This could rapidly change, since, as noted below, E. coli rapidly acquires drug resistance
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Kumkum / safron - Crocus sativus
Crocuses belong to the family Iridaceae. The saffron crocus is classified as Crocus sativus, It is a shrub. Leaves are seen towards the base of the stem and are compactly arranged.Read More about safron.....
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