On 11 th March 2020, the World Health Organization (WHO) declared the COVID-19 caused by the 2019 novel coronavirus (2019-nCoV) a pandemic. [1] Currently, there are more than 3 million cases and one lakh deaths reported, and still counting. [2] This has brought radical changes in all aspects of our lives. Social distancing and restrictive movement policies have markedly deranged traditional educational practices. The time course of these changes is indeterminate. These have affected conventional in-person ophthalmic education and training. There is a pressing need to innovate and implement alternative educational and assessment strategies. The COVID-19 pandemic has provided us with an opportunity to pave the way for introducing digital learning in ophthalmology.

Methyl 3-(1'-m-iodobenzyloxyethyl)-3-devinylpyropheophorbide-a (2), obtained in a sequence of reactions from pyropheophorbide-a (a chlorophyll-a derivative), was found to be a promising imaging agent and a photosensitizer for photodynamic therapy (PDT). The electrophilic aromatic iodination of the corresponding trimethylstannyl intermediate with Na124I in the presence of an Iodogen bead afforded 124I-labeled photosensitizer 4 with >95% radioactive specificity. In addition to drug-uptake, the light fluence and fluence rate that were used for the light treatment had a significant impact in long-term tumor cure. The iodo photosensitizer 2 (nonlabeled analogue of 4) produced 100% tumor cure (5/5 mice were tumor free on day 60) at a dose of 1.5 micromol/kg and a light dose of 128 J/cm2, 14 mW/cm2 for 2.5 h (lambda(max) 665 nm) at 24 h postinjection. The photosensitizer also showed promising tumor fluorescence and PET imaging ability. Our present work demonstrates the utility of the first 124I-labeled photosensitizer as a "multimodality agent", which could further be improved by using more tumor-avid and/or target-specific photosensitizers.

Purpose To report and compare clinical and pathological features of hydrophilic acrylic intraocular lenses (IOLs) of three major designs, explanted from patients who had visual disturbances caused by opacification of the lens optic. Methods Eighty-seven hydrophilic acrylic IOLs (25 Hydroview TM , 54 SC60B-OUV, and 8 Aqua-Sense TM lenses) were explanted and sent to our center. Most patients became symptomatic during the second year after cataract surgery. A fine granularity was observed on the surface of the lens optic in the case of Hydroview TM . With the SC60B-OUV and Aqua-Sense TM lenses, the opacity resembled a nuclear cataract. Gross examination, light microscopy and staining with alizarin red and the von Kossa method (for calcium) were performed. Some lenses were submitted for scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Results Light microscopic and SEM analyses revealed the presence of irregular granular deposits on the external optical surfaces of Hydroview TM lenses. With the SC60B-OUV lenses, the opacity was caused by the presence of multiple fine, granular deposits within the lens optic, distributed in a line parallel to the anterior and posterior curvatures of the optic, with a clear zone just beneath its external surfaces. The Aqua-Sense TM lenses exhibited both patterns simultaneously. The deposits in all cases stained positive with alizarin red and von Kossa method. EDS also demonstrated the presence of calcium and phosphates within the deposits. Conclusion Differences in the water content of the hydrophilic acrylic materials used in the manufacture of these three lens designs may be responsible for the different patterns of calcium precipitation. Careful clinical follow up of patients implanted with these lenses is necessary to determine if this phenomenon is rare and sporadic or may be more widespread.

No abstract

This study seems to confirm the sandwich theory of posterior capsule opacification in eyes with an IOL and suggests that fibronectin may be the major extracellular protein responsible for the attachment of hydrophobic soft acrylate (AcrySof(R)) IOLs to the capsular bag. This may represent a true bioactive bond between the IOL and lens epithelial cells or between the IOL and the capsular bag and may be one reason the PCO and neodymium:YAG capsulotomy rates are lower in eyes with a soft acrylate IOL.

The carbohydrate moieties on conjugating with 3-(1′-hexyloxyethyl)-3-devinyl pyropeophorbide-a (HPPH) altered the uptake and intracellular localization from mitochondria to lysosomes. In vitro, HPPH-Gal 9 PDT showed increased PDT efficacy over HPPH-PDT as detectable by the oxidative cross-linking of nonphosphorylated STAT3 and cell killing in ABCG2-expressing RIF cells but not in ABCG2-negative Colon26 cells. This increased efficacy in RIF cells could at least partially be attributed to increased cellular accumulation of 9, suggesting a role of the ABCG2 transporter for which HPPH is a substrate. While such differences in the accumulation in HPPH derivatives by tumor tissue in vivo were not detectable, 9 still showed an elevated light dose-dependent activity compared to HPPH in mice bearing RIF as well as Colon26 tumors. Further optimization of the carbohydrate conjugates at variable treatment parameters in vivo is currently underway.

No abstract

This is the first clinicopathological report of optic opacification occurring with this hydrophilic acrylic IOL model. Studies of similar cases with this lens should be done to determine the incidence and possible mechanisms of the phenomenon.