A Bis-Glycosylamine Strategy for the Synthesis of Dimeric Iminosugars Based on a DAB-1 Scaffold.

A straightforward synthetic route towards DAB-1 scaffolded dimeric iminosugars is described here, starting from readily available bis-glycosylamines. The method allows the integration of a variety of linkages (aryl, alkyl, polyethyleneglycol chains) between both iminosugars through the choice of the bis-amine used in the first step. Moreover, an additional substituent (allyl, ethynyl) may be inserted into the structure via nucleophilic addition of an organometallic reagent to the starting bis-glycosylamine.

Quantifying tear exchange during rigid contact lens wear using corneoscleral profilometry: A proof of concept study.

Introduction: Tear exchange during contact lens wear is essential for ocular surface integrity, facilitating debris removal, and maintaining corneal metabolism. Fluorophotometry and fluorogram methods are typically used to measure tear exchange, which require hardware modifications to a slit lamp biomicroscope. This manuscript introduces an alternative method using a corneoscleral profilometer, the Eye Surface Profiler (ESP), to quantify tear exchange during corneal and scleral rigid lens wear by assessing fluorescence intensity changes over time.

Association between axial elongation and corneal topography in children undergoing orthokeratology with different back optic zone diameters.

Purpose: To explore the associations between myopia defocus dosage (MDD), aberration coefficients (primary spherical aberration and coma), and axial elongation in children undergoing orthokeratology (ortho-k) with back optic zone diameters (BOZD) of 5 mm and 6 mm over 2 years.

Methods: Data from 80 participants from two ortho-k studies were analyzed: 22 and 58 children wore lenses with 5-mm and 6-mm BOZD, respectively. Four MDD metrics were calculated from corneal topography data over a 5-mm pupil for the 1-month and 24-month visits: the circumferential, flat, steep, and volumetric MDD.

Contact lens fenestrations and channels in relation to tear exchange and corneal oedema.

Oxygen delivery and tear exchange are considered essential to maintain corneal homoeostasis during contact lens wear. Since the 1940s, fenestrations and back surface channels have been utilised in scleral, corneal rigid, and soft contact lenses in an attempt to enhance corneal oxygen transmission, facilitate the removal of carbon dioxide from the post-lens tear layer, minimise corneal oedema and prevent post-lens tear stagnation. This review examines the use of contact lens fenestrations and channels in both clinical and laboratory settings, and the effect of these modifications upon tear exchange and corneal oedema.