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Background Quantification of lactate dehydrogenase (LDH) release is a widely accepted assay for the quantitative determination of cell viability and late-stage apoptosis. Major disadvantages of commercially available LDH assay kits include proprietary formulations, limited options for optimization and high cost, all resulting in limited reproducibility in research applications. New Method Here, we describe a novel, custom LDH assay suitable in the context of plate reader-based screening of drug candidates for glioprotection, but with wide applicability to other cell types and experimental paradigms. Results We developed a novel and highly reproducible LDH release assay that is more cost-effective than commercially available assays with comparable performance. The assay was validated by assessing 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid antioxidant protection against tert-butylhydroperoxide-induced oxidative stress in C6 astroglioma cells. Assay performance was validated by direct comparison and compatible with other methods of measuring cellular viability, namely 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and 6-carboxy-2′, 7′ dichlorodihydrofluorescein diacetate assays. Comparison with Existing Method(s) There was no statistically significant difference between results obtained with the novel custom assay and a commercially available assay CytoTox96® (Promega, Madison, WI). Conclusions The novel custom LDH release assay allows the reproducible quantification of cell viability and is highly cost-effective when compared to commercially available assays (approximately 25 times cheaper). In addition and in contrast to commercially available assays, the identification and detailed description of all assay components and procedures provide greater control over experimental conditions and design. We provide a detailed standard operating procedure permitting our novel assay to be readily adapted depending on experimental requirements.

Background Glaucoma patients undergoing phacoemulsification alone have a higher rate of refractive surprise compared to patients without glaucoma. This risk is further increased with combined filtering procedures. Indeed, there are few and conflicting reports on the effect of combined phacoemulsification and micro-invasive glaucoma surgery (MIGS). Here, we look at refractive outcomes of glaucoma patients undergoing phacoemulsification with and without Kahook Dual Blade (KDB) goniotomy. Methods Retrospective chart review of 385 glaucomatous eyes of 281 patients, which underwent either phacoemulsification alone (n = 309) or phacoemulsification with KDB goniotomy (n = 76, phaco-KDB) at the University of Colorado. The main outcome was refractive surprise defined as the difference in target and postoperative refraction spherical equivalent greater than ±0.5 Diopter (D). Results Refractive surprise greater than ±0.5 D occurred in 26.3% of eyes in the phaco-KDB group and 36.2% in the phacoemulsification group (p = 0.11). Refractive surprise greater than ±1.0 D occurred in 6.6% for the phaco-KDB group and 9.7% for the phacoemulsification group (p = 0.08). There was no significant difference in risk of refractive surprise when pre-operative IOP, axial length, keratometry or performance of KDB goniotomy were assessed in univariate analyses. Conclusion There was no difference between refractive outcomes of glaucomatous patients undergoing phacoemulsification with or without KDB goniotomy.

Introduction: Here we describe a new cataract chop technique that is most valuable for two groups of ophthalmologists: (1) experienced surgeons encountering challenging nuclear fragmentation due to mature cataracts or zonulopathies, and (2) inexperienced surgeons wishing to develop skills necessary for chopping techniques. Methods: We have termed this new method ''rotary chop,'' since the partial thickness pilot holes created by the phacoemulsification (phaco) tip around the periphery of the nucleus produce a rotary phone dial appearance on the surface of the cataract. By creating these pilot holes, the surgeon is able to easily place the chopper deep into the body of the nucleus, avoiding the need to apply vertical piercing force to the nucleus. Results: The patient in the technical video had a 4? nuclear sclerosis cataract. The preoperative vision in this eye was counting fingers at 2 feet with no improvement with refraction. On postoperative day 1, visual acuity had improved to 20/80. By postoperative week 1, best-corrected visual acuity was 20/20 (20/25-2 uncorrected). Conclusion: This method avoids unnecessary zonular stress. Additionally, inexperienced surgeons using this technique during routine cataract surgery are able to quickly master the movements necessary for both vertical and horizontal chop in a safer environment.

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