Comparison of axial length measurements in silicone oil-filled eyes using SS-OCT and partial coherence interferometry.

PURPOSE: To compare axial length (AL) measurements in silicone oil (SO)-filled eyes using swept-source optical coherence tomography (SS-OCT) (the IOLMaster 700 and OA2000) and partial coherence interferometry (the IOLMaster 500). SETTING: Zhongshan Ophthalmic Center, Guangzhou, China. DESIGN: Cross-sectional study. METHODS: We enrolled phakic patients who underwent SO removal surgery. The AL measurements by the IOLMaster 500, IOLMaster 700, and OA2000, both before and after SO removal, were compared. Multiple regression analysis was performed to identify risk factors for the differences between preoperative and postoperative AL measurements. RESULTS: 68 patients (68 eyes) with a mean age of 46.43 ± 13.24 years were included. No statistically significant difference was observed in the preoperative AL measurements between the IOLMaster 500 and IOLMaster 700 (25.48 ± 2.51 mm vs 25.49 ± 2.46 mm; P = .63), whereas the OA2000 yielded shorter AL (25.34 ± 2.36 mm) (both P < .001). After SO removal, the AL measurements showed no statistically significant differences among the 3 devices. In reference to the postoperative AL, the IOLMaster 500 and IOLMaster 700 tended to overestimate the AL in SO-filled eyes (both P < .001), and this measurement error increased with longer AL (ß = 0.08 and 0.05, respectively; both P < .001). No statistically significant difference was observed between preoperative and postoperative AL measurements by the OA2000 ( P = .18). CONCLUSIONS: The OA2000 is the preferred biometer for AL measurement in SO-filled eyes, whereas the IOLMaster 500 and IOLMaster 700 overestimate the AL especially for long eyes, which needs adjustment in clinical use.

Accuracy of new-generation intraocular lens calculation formulas in eyes undergoing combined silicone oil removal and cataract surgery.

PURPOSE: To compare the performance of new-generation and traditional intraocular lens (IOL) calculation formulas in eyes undergoing combined silicone oil (SO) removal and cataract surgery and to evaluate the prediction accuracy of Wang-Koch (WK) adjustment in SO-filled long eyes. SETTING: Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. DESIGN: Retrospective consecutive case-series study. METHODS: New-generation formulas (Barrett Universal II, Emmetropia Verifying Optical, Kane, and Ladas Super formulas) and traditional formulas (Haigis, Hoffer Q, Holladay 1, and SRK/T formulas) were compared. The performance of WK adjustment was assessed in eyes with axial length more than 26 mm. The median absolute error (MedAE) was the main parameter to evaluate the accuracy of formulas. RESULTS: A total of 211 participants (211 eyes) who underwent combined SO removal and phacoemulsification with IOL implantation were included. Four new-generation formulas displayed statistically significant lower MedAE (0.32 to 0.35 diopter [D]) and higher percentage of eyes within ±1.00 D of prediction error (85.31% to 87.20%) compared with those of the traditional formulas (MedAE: 0.39 to 0.50 D; ±1.00 D: 81.04% to 81.99%, P < .05). For SO-filled long eyes, all traditional formulas showed hyperopic bias (0.36 to 0.65 D, P < .05), except for Haigis formula (0.28 D, P = .083), and this bias could be corrected by WK adjustment (P > .05). EVO formula displayed the lowest MedAE both in total (0.32 D) and in long eyes (0.33 D). CONCLUSIONS: New-generation formulas and traditional formulas with WK adjustment showed satisfactory prediction accuracy in eyes undergoing combined SO removal and cataract surgery. EVO formula displayed the highest accuracy.

Smart polymeric nanoparticles with pH-responsive and PEG-detachable properties for co-delivering paclitaxel and survivin siRNA to enhance antitumor outcomes.

BACKGROUND: The co-delivery of chemotherapeutic agents and small interfering RNA (siRNA) within one cargo can enhance the anticancer outcomes through its synergistic therapeutic effects. MATERIALS AND METHODS: We prepared smart polymeric nanoparticles (NPs) with pH-responsive and poly(ethylene glycol) (PEG)-detachable properties to systemically co-deliver paclitaxel (PTX) and siRNA against survivin gene for lung cancer therapy. The cationic polyethyleneimine-block-polylactic acid (PEI-PLA) was first synthesized and characterized, with good biocompatibility. PTX was encapsulated into the hydrophobic core of the PEI-PLA polymers by dialysis, and then the survivin siRNA was loaded onto the PTX-loaded NPs (PEI-PLA/PTX) through electrostatic interaction between siRNA and PEI block. Finally, the negatively charged poly(ethylene glycol)-block-poly(L-aspartic acid sodium salt) (PEG-PAsp) was coated onto the surface of NPs by electrostatic interaction to form final smart polymeric NPs with mean particle size of 82.4 nm and zeta potential of 4.1 mV. After uptake of NPs by tumor cells, the PEG-PAsp segments became electrically neutral owing to the lower endosome pH and consequently detached from the smart NPs. This process allowed endosomal escape of the NPs through the proton-sponge effect of the exposed PEI moiety. RESULTS: The resulting NPs achieved drug loading of 6.04 wt% and exhibited good dispersibility within 24 h in 10% fetal bovine serum (FBS). At pH 5.5, the NPs presented better drug release and cellular uptake than at pH 7.4. The NPs with survivin siRNA effectively knocked down the expression of survivin mRNA and protein owing to enhanced cell uptake of NPs. Cell counting kit-8 (CCK-8) assay showed that the NPs presented low systemic toxicity and improved antiproliferation effect of PTX on A549 cells. Moreover, in vivo studies demonstrated that accumulated NPs in the tumor site were capable of inhibiting the tumor growth and extending the survival rate of the mice by silencing the survivin gene and delivering PTX into tumor cells simultaneously. CONCLUSION: These results indicate that the prepared nano-vectors could be a promising co-delivery system for novel chemo/gene combination therapy.

PEGylation of Lumbrokinase improves pharmacokinetic profile and enhances anti­thrombotic effect in a rat carotid artery thrombosis model.

The present study aimed to prepare injectable Lumbrokinase (LK) with long circulation time in addition to enhanced anti-thrombotic efficacy. Following preparation, the pharmacokinetic and anti­thrombotic effect of the drug in a rat carotid artery thrombosis model was evaluated. The drug was prepared by conjugation of LK with mPEG­SC20000 as previously reported. The pharmacokinetics of the mPEG­SC20000­LK were then examined and the anti­thrombotic activity in an artery­vein bypass thrombosis rat model was evaluated. Finally, the parameters of fibrinolysis including thromboxane B2, prostaglandin F1α, tissue plasminogen activator and plasminogen activator inhibitor­1 were compared between native LK and mPEG­SC20000­LK in a FeCl3­induced carotid artery thrombosis rat model. mPEG­SC20000­LK was successfully prepared by PEGylation of LK with mPEG20000­SC in optimal conditions. Pharmacokinetic analysis demonstrated that the biological half­life of the mPEG20000­SC­LK increased by 2.2­fold compared with native LK. In vivo anti­thrombotic analysis indicated that mPEG20000­SC­LK exhibited a greater anti­thrombotic effect in artery­vein bypass thrombosis and FeCl3-induced carotid artery thrombosis models compared with native LK. In conclusion, injectable PEGylated LK with prolonged half-life and enhanced anti­thrombotic effect is a potential anti­thrombotic agent for long­acting treatment of the thrombus diseases.

Docetaxel-loaded PEG-albumin nanoparticles with improved antitumor efficiency against non-small cell lung cancer.

The aim of the present study was mainly to assess the advantage of docetaxel-loaded PEG-albumin nanoparticles (PEG-DANPs) against non-small cell lung cancer (NSCLC) compared with the commercial product of docetaxel (Aisu®) and docetaxel-albumin nanoparticles (DANPs). We made systematic assessments on these three drugs against NSCLC both in vitro and in vivo. Based on our experiments, PEG-DANPs showed a dose- and time-dependent efficacy in the in vitro cytotoxicity studies; the tumors growth and the metastases in the livers of NSCLC-bearing nude mice in vivo were reduced dmarkedly by PEG-DANPs, and the PEG-DANP-treated mice had a minimum of weight loss; furthermore, the mice which were treated with PEG-DANPs can survive longer than the other groups. In conclusion, the PEG-DANPs have the lowest side-effects, and the highest antitumor and metastases activity of the three drugs, and it may provide an alternative to patients with NSCLC.

A comparative study on the effect of docetaxel-albumin nanoparticles and docetaxel-loaded PEG-albumin nanoparticles against non-small cell lung cancer.

The present study mainly compared the effect of docetaxel-albumin nanoparticles (DANPs) and docetaxel-loaded PEG-albumin nanoparticles (PEG-DANPs) against non-small cell lung cancer (NSCLC). We made systematic assessments on these three drugs against NSCLC both in vitro and in vivo. With the purpose of eliminating side-effects of the commercial formulation (Tween-80) and prolonging the blood circulation time, we used emulsion-evaporation cross-link method to prepare DANPs and PEG-DANPs. The DANPs had an average particle size of 163.4 ± 3.76 nm, a zeta potential of -19.4 ± 0.18 mV, a polydispersity index of 0.143 ± 0.03, a drug loading of 8.71 ± 0.98%, and an encapsulation efficiency of 93.58 ± 0.86%; the average particle size of PEG-DANPs is 169.19 ± 2.36 nm, zeta potential is -18.2 ± 0.21 mV, with a polydispersity index of 1.56 ± 0.05, a drug loading of 8.72 ± 1.05% and an encapsulation efficiency of 95.4 ± 5.5%. PEG-DANPs showed a dose- and time-dependent efficacy in cytotoxicity studies in vitro; the hemolysis test indicated that PEG-DANPs had less hemocytolysis than Aisu® and DANPs; in addition, a more prolonged circulation time and sustained in vitro release behavior were observed in the PEG-DANPs compared with Aisu® and DANPs; the cellular uptake test in vitro demonstrated that PEG-DANPs could be absorbed easier into the nucleus; furthermore, the tumor growth of NSCLC-bearing nude mice in vivo was reduced the most by PEG-DANPs. In conclusion, the PEG-DANPs have the lowest side-effects, the highest antitumor activity with the longest blood circulation time of the three drugs, and it will provide an alternative to patients with NSCLC.