Manufacturers: Schering corp sub schering plough corp, Pharmafair inc +29 more
Gentamicin is an aminoglycoside used to treat a wide variety of aerobic infections in the body.
Gentamicin is an aminoglycoside used to treat a wide variety of aerobic infections in the body.
There are 3 key phases of aminoglycoside entry into cells. The first “ionic binding phase” occurs when polycationic aminoglycosides bind electrostatically to negatively charged components of bacterial cell membranes including with lipopolysaccharides and phospholipids within the outer membrane of Gram-negative bacteria and to teichoic acids and phospholipids within the cell membrane of Gram-positive bacteria. This binding results in displacement of divalent cations and increased membrane permeability, allowing for aminoglycoside entry. The second “energy-dependent phase I” of aminoglycoside entry into the cytoplasm relies on the proton-motive force and allows a limited amount of aminoglycoside access to its primary intracellular target - the bacterial 30S ribosome. This ultimately results in the mistranslation of proteins and disruption of the cytoplasmic membrane. Finally, in the “energy-dependent phase II” stage, concentration-dependent bacterial killing is observed. Aminoglycoside rapidly accumulates in the cell due to the damaged cytoplasmic membrane, and protein mistranslation and synthesis inhibition is amplified. The necessity of oxygen-dependent active transport explains why aminoglycosides are ineffective against anaerobic bacteria. Hence, aminoglycosides have both immediate bactericidal effects through membrane disruption and delayed bactericidal effects through impaired protein synthesis; observed experimental data and mathematical modeling support this two-mechanism model. Inhibition of protein synthesis is a key component of aminoglycoside efficacy. Structural and cell biological studies suggest that aminoglycosides bind to the 16S rRNA in helix 44 (h44), near the A site of the 30S ribosomal subunit, altering interactions between h44 and h45. This binding also displaces two important residues, A1492 and A1493, from h44, mimicking normal conformational changes that occur with successful codon-anticodon pairing in the A site. Overall, aminoglycoside binding has several negative effects including inhibition of translation, initiation, elongation, and ribosome recycling. Recent evidence suggests that the latter effect is due to a cryptic second binding site situated in h69 of the 23S rRNA of the 50S ribosomal subunit. Also, by stabilizing a conformation that mimics correct codon-anticodon pairing, aminoglycosides promote error-prone translation. Mistranslated proteins can incorporate into the cell membrane, inducing the damage discussed above.
1.本品适用于敏感铜绿假单胞菌、变形杆菌（吲哚阳性和阴性）属、大肠埃希菌、克雷伯菌属、肠杆菌属、沙雷菌属、柠檬酸杆菌属以及葡萄球菌属（不包括耐甲氧西林菌株）所致的严重感染；临床上本品常与β内酰胺类或其他抗菌药物联合应用。本品与青霉素G（或氨苄西林）联合应用治疗肠球菌感染； 2.本品用于铜绿假单胞菌或葡萄球菌属所致的严重中枢神经系统感染（如脑膜炎、脑室炎）时，可同时用本品鞘内注射作为辅助治疗； 3.本品不适用于单纯性尿路感染初治，除非病原菌对其他毒性较低的抗菌药物不敏感，本品对链球菌属中多数菌种（尤其D组）、肺炎链球菌和厌氧菌（如拟杆菌属或梭状芽孢杆菌属）无效； 4.本品口服可用于肠道感染或结肠手术前准备，也可用本品肌注合并克林霉素或甲硝唑以减少结肠手术后感染率。 5.局部外用适用于治疗敏感细菌所致的外眼感染，如结膜炎、结膜炎、泪囊炎、睑缘炎、睑板腺炎等。
39 associated conditions
