RESUMO
Lariat ethers are macrocyclic polyethers-crown ethers-to which sidearms are appended. 4,13-Diaza-18-crown-6 having twin alkyl chains at the nitrogens show biological activity. They exhibit antibiotic activity, but when co-administered at with an FDA-approved antibiotic, the latter's potency is often strongly enhanced. Potency enhancements and resistance reversals have been documented in vitro for a range of Gram-negative and Gram-positive bacteria with a variety of antimicrobials. Strains of E. coli and Staphylococcus aureus having resistance to a range of drugs have been studied and the potency enhancements (checkerboards) are reported here. Drugs included in the present study are ampicillin, cefepime, chlortetracycline, ciprofloxacin, doxycycline, kanamycin, minocycline, norfloxacin, oxycycline, penicillin G, and tetracycline. Enhancements of norfloxacin potency against S. aureus 1199B of up to 128-fold were observed. The properties of these lariat ethers have been studied to determine solubility, their membrane penetration, cytotoxicity and mammalian cell survival, and their effect on bacterial efflux pumps. It is shown that in some cases, the lariat ethers have complex antimicrobials with considerable selectivity. Based on these observations, including 1:1 complexation between lariat ethers and antimicrobials and the cytotoxicity of the MeI salts showing a separation index of 32-fold, they hold significant potential for further development.
RESUMO
BACKGROUND/AIMS: To report the short-term safety profile and clinical outcomes of scleral fixation of intraocular lenses (IOLs) using Gore-Tex suture. METHODS: Retrospective, interventional case series. 85 eyes of 84 patients undergoing ab externo scleral fixation of a Bausch and Lomb Akreos AO60 or Alcon CZ70BD IOL using Gore-Tex suture. Primary outcome measures were change in visual acuity and occurrence of intraoperative and postoperative complications with minimum follow-up of 90â days. RESULTS: 85 eyes of 84 patients were identified. Mean logarithm of the minimum angle of resolution visual acuity improved from 1.43±0.72 (20/538 Snellen equivalent) preoperatively to 0.64±0.61 (20/87 Snellen equivalent) postoperatively (p<0.001). Mean follow-up was 325â days (median 264â days, range 90-996â days). There were no intraoperative complications noted. Postoperative complications included hypotony in eight patients (9.4%), ocular hypertension in six eyes (7%), vitreous haemorrhage in six eyes (7%), hyphema in two eyes (2%), serous choroidal detachment in two eyes (2%), cystoid macular oedema in two eyes (2%) and corneal oedema in one eye (1%). There were no cases of postoperative endophthalmitis, suture erosion/breakage, retinal detachment, suprachoroidal haemorrhage, uveitis-glaucoma-hyphema syndrome or persistent postoperative inflammation in the follow-up period. CONCLUSIONS: Ab externo scleral fixation of IOLs with Gore-Tex suture was well tolerated in all cases. No suture-related complications were encountered. This procedure led to improvement in visual acuity and was not associated with significant intraoperative or postoperative complications.