Applications aminoglycosides

Luciferase assay. In this technique, firefly luciferase is used to measure small amounts of adenosine triphosphate (ATP) in a bacterial culture, ATP levels being reduced by the inhibitory action of aminoglycoside antibiotics. This method may find more application in the future as more active and reliable luciferase preparations become available. 

Neomycin is a readily ionisable molecule and should thus be separable from other antibiotics by application of an electric field (zone electrophoresis). Various workers have successfully applied this technique to neomycin and Table 10 summarises the conditions reported in the literature. A number of authors described the qualitative separation of neomycin from other chemical-types of antibiotics using paper-electro-phoresis181,185,187 while Ochabl89 described systems specifically designed to separate compounds within the aminoglycoside group of antibiotics. 

Takeda, N. Harada, K.-L Suzuki, M. Tatematsu, A. Kubodera, T. Application of Emitter CI-MS to Stractural Characterization of Aminoglycoside Antibiotics. Org. Mass Spectrom. 1982,17, 247-252. 

Yang, W. C., Yu, A. M., and Chen, H. Y. (2001). Applications of a copper microparticle-modified carbon fiber microdisk array electrode for the simultaneous determination of aminoglycoside antibiotics by capillary electrophoresis. /. Chromatogr. A 905, 309—318. 

Although a number of chromatographic methods have been reported for determinations of aminoglycoside antibiotics in blood serum and urine, the application of chromatographic methods to residue analysis has been very limited. Shaikh et al (93) recently described an HPLC method for neomycin in animal tissue, and Lachatre et al (94) described a method for nine aminoglycosides in plasma, urine, and renal cortex tissue. Both procedures use post column derivatization with a-pthalaldehyde and fluorescence detection. 

Absorption of antimicrobial agents, influencing factors, 15 Acidophilin, food preservative, 94,95t Agglutination application, 150 description, 149-150 American foulbrood control oxytetracycline, 36-45 sulfathiazole, 36,37f Amikacin, use in food animals, 19 Aminoglycoside detection, by... 

Many applications of the aminoglycosides have been of historical significance in genetics and microbiology. For example, mutations to streptomycin resistance were employed as counterselective genetic markers in the historic experiments of William Hayes that demonstrated the existence of bacterial conjugation and the requirement of donor (Hfr or F-b) and receptor (F—) species. ... 

TABLE 1.1. Some of the Myriad Properties and Applications of the Aminoglycosides... 

Aminoglycosides remain clinically important antibiotics. NMR provided the initial breakthrough in structural understanding of aminoglycoside action on the ribosome, and it remains a powerful tool for the biophysical characterization of drug-RNA interaction. The combined use of NMR, X-ray crystallography, thermodynamic and functional assays, and computational methods is needed to drive forward the development of new aminoglycosides with improved clinical properties. The rich data described above, combined with the application of new synthetic methods, bode well for the future. 

Table 1.19. Some aminoglycoside antibiotics which have gained significant therapeutic application. Producer microorganisms are listed in brackets. In addition to naturally produced aminoglycosides, a number of semi-synthetic derivatives have also found medical application. Examples include amikacin, a semi-synthetic derivative of kanamycin and netilmicin, an N-ethyl derivative of sissomicin...

More versatile than the growth-inhibition assays and potentially applicable to determining the presence of different antibiotic residues in different matrices are the microbial receptor CHARM I and II test assays (19, 20). The Charm I test, developed exclusively for -lactams in milk, constitutes the first rapid test recognized by The Association of Official Analytical Chemists (AOAC) with a test time of 15 min (19). The speed and sensitivity of this test permitted testing of milk tankers before they unloaded at the processing plant (21). In 1984-1985, the CHARM I test was further developed to test for antibiotics beyond -lactams to include tetracyclines, sulfonamides, aminoglycosides, chloramphenicol, novobiocin, and macrolides. The extended version has been referred to as CHARM II test. 

Examples for the use of acetals such as 3, of 3-nitropropanal (1), and of 3-nitropropanol (2) or its O-protected derivatives are given in the references.22-24 A recent, notable application from this group is a short, high-yield synthesis of l-acosamine,25 the arabino isomer of 3-amino-2,3,6-trideoxyhexoses that form part of many antitumor aminoglycoside antibiotics 26... 

In this chapter, the latest applications published in the literature from 1994 to 1998 are reviewed. The following groups of antimicrobial agents are discussed tetracyclines, penicillins, poiyethers, aminoglycosides, macrolides, amphenicols, nitrofurans, sulphonamides, quinolones and other antimicrobials. 

These reactions were applied to the synthesis of phenol derivatives [32], aminoglycoside antibiotics [33] etc.. . and are of great interest in other synthetic applications, b) In the field of substitution reactions, a more recent application of photobromination reactions is described for the synthesis of L-iduronic acid derivatives from D-glu-curonic acid analogs 26. The C-5 photobrominated product 27 is reduced with tri-n-butyltin hydride to give a mixture of starting material and the L-idopyranuronate 28 by a supposed rapidly interconverting radical [29] (Scheme 14). 

Topical Antibiotic Monotherapy Localized impetiginized eczema lesions can be treated successfully with topical fusidic acid or mupirocin, whereas topical application of other antibiotics (neomycin as obsolete aminoglycosid, tetracyclines, or polymyxines) should be avoided.84 Especially in children with AD, fusidic acid resistance seems to be a particular problem reflecting the chronicity and the extent of the disease (see Section 30.2.2). 

Administration The highly polar, polycationic structure of the aminoglycosides prevents adequate absorption after oral administration. Therefore, all aminoglycosides (except neomycin [nee oh MYE sin]) must be given parenterally to achieve adequate serum levels. [Note The severe nephrotoxicity associated with neomycin precludes parenteral administration, and its current use is limited to topical application or oral treatment in hepatic coma to reduce the intestinal bacterial population.]... 

Neuromuscular paralysis This side effect most often results after direct intraperitoneal or intrapleural application of large doses of aminoglycosides. The mechanism responsible is a decrease in both the release of acetylcholine from prejunctional nerve endings and the sensitivity of the postsynaptic site. Patients with myasthenia gravis are particularly at risk. Prompt administration of calcium gluconate or neostigmine can reverse the block. 

Aminoglycosides are poorly absorbed from the gastrointestinal tract, so when used systemically they must be given parenterally. Note that penicillins or cephalosporins can inactivate aminoglycosides if mixed together in the same solution fiar injection or fiar topical application each drug must be administered separately. If topical fortified cefazolin and fortified tobramycin are used to treat a corneal ulcer, each should be prepared and administered in a separate bottle. 

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