Removal efficiencies of seven frequently detected antibiotics and related physiological responses in three microalgae species.

The main objective of this study is to investigate the effect of mixtures of seven widely used human antibiotics (ciprofloxacin, clarithromycin, erythromycin, metronidazole, ofloxacin, sulfamethoxazole, and trimethoprim) on the growth, pH, pigment production, and antibiotics removal of three microalgal species (Auxenochlorella protothecoides, Tetradesmus obliquus, and Chlamydomonas acidophila). Batch assays were conducted with media with antibiotic mixtures at 10, 50, and 100 µg L-1 for each antibiotic. The three microalgae species effectively removed the antibiotics without any growth inhibition, even when exposed to the highest antibiotic concentrations. Biosorption was reported as the primary mechanism for ciprofloxacin, clarithromycin, metronidazole, and ofloxacin, with up to 70% removal, especially in A. protothecoides and C. acidophila. A. protothecoides, a species never investigated for antibiotic removal, was the only microalgae exhibiting bioaccumulation and biodegradation of specific antibiotics, including sulfamethoxazole. Furthermore, in media with the highest antibiotic concentration, all three species exhibited increased chlorophyll (up to 37%) and carotenoid (up to 32%) production, accompanied by a pH decrease of 3 units. Generally, in the present study, it has been observed that physiological responses and the removal of antibiotics by microalgae are interlinked and contingent on the antibiotic levels and types.

A modified approach to actively remove high viscosity silicone oil through 23-gauge cannula.

AIM: To report a simple approach to actively remove high viscosity silicone oil through a 23-gauge cannula via pars plana. METHODS: Forty-eight eyes of 48 patients underwent silicone oil (5700 centistokes) removal (SOR) were enrolled. A section of blood transfusion set was prepared to connect a standard 23-gauge cannula and vitrectomy machine. Silicone oil was removed with suction of 500-mm Hg vacuum through the cannula. Main outcome measures were SOR duration, number of sutured sites, intraocular pressure (IOP), best-corrected visual acuity (BCVA), and complications. RESULTS: Silicone oil was successfully removed in all cases. The mean SOR time was 5.70±0.85min. Nine eyes (18.75%) needed suture partial sclerotomies. No intraoperative complications were noted. Transient hypotony (≤8 mm Hg) was seen in 3 eyes (6.25%) on postoperative day 1, but all resolved within 1wk. Retinal reattachment was achieved in all cases and no other postoperative complications were noted during 3-month following-up. BCVA at the final visit improved or stabilized in all patients comparing to the preoperative level. CONCLUSION: Active removal of high viscosity silicone oil through a 23-gauge instrument cannula jointed with blood transfusion set is a practical and reliable technique when considering two sides of efficacy and safety.

Efficacy and safety of active silicone oil removal through a 23-gauge transconjunctival cannula using an external vacuum pump.

AIM: To evaluate the efficacy and safety of active removal of silicone oil with low and high viscosity through a 23-gauge transconjunctival cannula using an external vacuum pump. METHODS: This study was conducted as a prospective, interventional case series. A total of 22 eyes of 21 patients [1000 centistokes (cSt): 17 eyes, 5700 cSt: 5 eyes] were included in this study. All patients underwent active silicone oil removal via the entire lumen of a 23-gauge microcannula with suction pressure of a 650-700 mm Hg vacuum using an external vacuum pump. A tubing adaptor from the Total Plus Pak(®) (Alcon, Fort Worth, USA) was used to join the microcannula and silicone vacuum tube connected to an external vacuum pump. Main outcome measures were mean removal time, changes of intraocular pressure (IOP) and visual acuity, and intraoperative and postoperative complications. RESULTS: Mean removal time (min) was 1.49±0.43 for 1000 cSt and 7.12±1.27 for 5700 cSt. The IOP was 18.57±7.48 mm Hg at baseline, 11.68±4.55 mm Hg at day 1 postoperatively (P<0.001), and 15.95±4.92, 16.82±3.81, 17.41±3.50, and 17.09±3.01 mm Hg after one week, one month, three months, and six months, respectively. All patients showed improved or stabilized visual acuity. There was no occurrence of intraoperative or postoperative complications during the follow up period. CONCLUSION: This technique for active removal of silicone oil through a 23-gauge cannula using an external vacuum pump is fast, effective, and safe as well as economical for silicone oil with both low and high viscosity in all eyes with pseudophakia, aphakia, or phakia.