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Cephalosporin
The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus '' Acremonium'', which was previously known as ''Cephalosporium''. Together with cephamycins, they constitute a subgroup of β-lactam antibiotics called cephems. Cephalosporins were discovered in 1945, and first sold in 1964. Discovery The aerobic mold which yielded cephalosporin C was found in the sea near a sewage outfall in Su Siccu, by Cagliari harbour in Sardinia, by the Italian pharmacologist Giuseppe Brotzu in July 1945. Structure Cephalosporin contains a 6-membered dihydrothiazine ring. Substitutions at position 3 generally affect pharmacology; substitutions at position 7 affect antibacterial activity, but these cases are not always true. Medical uses Cephalosporins can be indicated for the prophylaxis and treatment of infections caused by bacteria susceptible to this particular form of antibiotic. First-generation cephalosporins are active predominant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalosporin C
Cephalosporin C is an antibiotic of the cephalosporin class. It was isolated from a fungus of the genus '' Acremonium'' and first characterized in 1961. Although not a very active antibiotic itself, synthetic analogs of cephalosporin C, such as cefalotin, became some of the first marketed cephalosporin antibiotic drugs. Cephalosporin C strongly absorbs ultraviolet light, is stable to acid, is non-toxic and has ''in vivo'' activity in mice. Cephalosporin C, which has a similar structure to penicillin N, was never commercialized. Cephalosporin C was a lead compound for the discovery and production of many other cephalosporins. Cephalosporins are drugs used for some people who are allergic to penicillin. Uses Cephalosporins are used to treat bacterial infections such as respiratory tract infections, skin infections and urinary tract infections. When a cephalosporin or any other antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephamycin
Cephamycins are a group of β-lactam antibiotics. They are very similar to cephalosporins, and the cephamycins are sometimes classified as cephalosporins. Like cephalosporins, cephamycins are based upon the cephem nucleus. Unlike most cephalosporins, cephamycins are a very efficient antibiotic against anaerobic microbes. Cephamycins were originally produced by ''Streptomyces'', but synthetic ones have been produced as well. Cephamycins possess a methoxy group at the 7-alpha position. In addition, cephamycins have been shown to be stable against extended-spectrum beta-lactamase (ESBL) producing organisms, although their use in clinical practice is lacking for this indication. Examples Cephamycins include: * Cefoxitin * Cefotetan * Cefmetazole References Cephalosporin antibiotics {{antibiotic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephem
Cephems are a sub-group of β-lactam antibiotics including cephalosporins and cephamycin Cephamycins are a group of β-lactam antibiotics. They are very similar to cephalosporins, and the cephamycins are sometimes classified as cephalosporins. Like cephalosporins, cephamycins are based upon the cephem nucleus. Unlike most cephalospor ...s. It is one of the most common 4-membered ring heterocycles. Produced by actinomycetes, cephamycins were found to display antibacterial activity against a wide range of bacteria, including those resistant to penicillin and cephalosporins. The antimicrobial properties of Cephem include the attachment to certain penicillin-binding proteins that are involved in the production of cell walls of bacteria. Research Researchers have developed antibiotics that include cephems and they have tried to test them clinically. Many of the antibiotics that are manufactured have different efficiencies based on the amount used, their strength, and their anti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giuseppe Brotzu
Giuseppe Brotzu ( Cagliari, 24 January 1895 – Cagliari, 8 April 1976) was an Italian pharmacologist and politician. Biography Giuseppe Brotzu was born in Ghilarza, a town now part of the Province of Oristano, Sardinia. He graduated from the University of Cagliari, Sardinia in (1919) and later completed the specialization in Hygiene at University of Siena in 1922. He graduated in Medicine and Surgery at the University of Bologna in 1925. He became a professor at the University of Modena and Reggio Emilia in 1932, and between 1939 and 1943 he was the director of University of Cagliari. Scientific research Brotzu is recognized as the discoverer of the cephalosporin-based antibiotics, that were first isolated from cultures of '' Cephalosporium'' (now known as '' Acremonium'') in 1948. He noticed that these cultures produced substances that were effective against '' Salmonella typhi'', the cause of typhoid fever, which had beta-lactamase. He was awarded the '' Laur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prophylaxis
Preventive healthcare, or prophylaxis, is the application of healthcare measures to prevent diseases.Hugh R. Leavell and E. Gurney Clark as "the science and art of preventing disease, prolonging life, and promoting physical and mental health and efficiency. Leavell, H. R., & Clark, E. G. (1979). Preventive Medicine for the Doctor in his Community (3rd ed.). Huntington, NY: Robert E. Krieger Publishing Company. Disease and disability are affected by environmental factors, genetic predisposition, disease agents, and lifestyle choices, and are dynamic processes that begin before individuals realize they are affected. Disease prevention relies on anticipatory actions that can be categorized as primal, primary, secondary, and tertiary prevention. Each year, millions of people die of preventable causes. A 2004 study showed that about half of all deaths in the United States in 2000 were due to preventable behaviors and exposures. Leading causes included cardiovascular disease, chron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit the air, soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-positive
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain is used by microbiologists to place bacteria into two main categories, gram-positive (+) and gram-negative bacteria, gram-negative (−). Gram-positive bacteria have a thick layer of peptidoglycan within the cell wall, and gram-negative bacteria have a thin layer of peptidoglycan. Gram-positive bacteria retain the crystal violet stain used in the test, resulting in a purple color when observed through an optical microscope. The thick layer of peptidoglycan in the bacterial cell wall retains the Stain (biology), stain after it has been fixed in place by iodine. During the decolorization step, the decolorizer removes crystal violet from all other cells. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staphylococcus
''Staphylococcus'', from Ancient Greek σταφυλή (''staphulḗ''), meaning "bunch of grapes", and (''kókkos''), meaning "kernel" or " Kermes", is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillales. Under the microscope, they appear spherical ( cocci), and form in grape-like clusters. ''Staphylococcus'' species are facultative anaerobic organisms (capable of growth both aerobically and anaerobically). The name was coined in 1880 by Scottish surgeon and bacteriologist Alexander Ogston (1844–1929), following the pattern established five years earlier with the naming of '' Streptococcus''. It combines the prefix "staphylo-" (from ), and suffixed by the (from ). Staphylococcus was one of the leading infections in hospitals and many strains of this bacterium have become antibiotic resistant. Despite strong attempts to get rid of them, staphylococcus bacteria stay present in hospitals, where they can infect people who are most at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penicillin Binding Proteins
Penicillin-binding proteins (PBPs) are a group of proteins that are characterized by their affinity for and binding of penicillin. They are a normal constituent of many bacteria; the name just reflects the way by which the protein was discovered. All β-lactam antibiotics (except for tabtoxinine-β-lactam, which inhibits glutamine synthetase) bind to PBPs, which are essential for bacterial cell wall synthesis. PBPs are members of a subgroup of transpeptidase enzymes called DD-transpeptidases. Diversity There are a large number of PBPs, usually several in each organism, and they are found as both membrane-bound and cytoplasmic proteins. For example, Spratt (1977) reports that six different PBPs are routinely detected in all strains of '' E. coli'' ranging in molecular weight from 40,000 to 91,000. The different PBPs occur in different numbers per cell and have varied affinities for penicillin. The PBPs are usually broadly classified into high-molecular-weight (HMW) and low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptococcus
''Streptococcus'' is a genus of gram-positive spherical bacteria that belongs to the family Streptococcaceae, within the order Lactobacillales (lactic acid bacteria), in the phylum Bacillota. Cell division in streptococci occurs along a single axis, thus when growing they tend to form pairs or chains, which may appear bent or twisted. This differs from staphylococci, which divide along multiple axes, thereby generating irregular, grape-like clusters of cells. Most streptococci are oxidase-negative and catalase-negative, and many are facultative anaerobes (capable of growth both aerobically and anaerobically). The term was coined in 1877 by Viennese surgeon Albert Theodor Billroth (1829–1894), by combining the prefix "strepto-" (from ), together with the suffix "-coccus" (from Modern , from .) In 1984, many bacteria formerly grouped in the genus ''Streptococcus'' were separated out into the genera '' Enterococcus'' and '' Lactococcus''. Currently, over 50 species are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative
Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists of a thin peptidoglycan cell wall sandwiched between an inner ( cytoplasmic) membrane and an outer membrane. These bacteria are found in all environments that support life on Earth. Within this category, notable species include the model organism '' Escherichia coli'', along with various pathogenic bacteria, such as '' Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and '' Yersinia pestis''. They pose significant challenges in the medical field due to their outer membrane, which acts as a protective barrier against numerous antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and the antimicrobial enzyme lysozyme produced by animals as part of their innate immune system. Furthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
