Quantitative Characterization of Modified Lignin Using Solid-State C NMR Spectroscopy.

Solid-state C nuclear magnetic resonance (NMR) spectroscopy with magic angle spinning (MAS) and direct polarization (DP) techniques is a valuable tool for quantitative and reliable characterization of lignin derivatives, specifically for determining these chemical structures and the degree of substitution upon chemical modification. In this study, the DPMAS C NMR spectroscopy was used in a quantitative study of the esterifying reaction in lignin derivatives, which allowed the whole lignin structure to be determined. This quantitative evaluation system using DPMAS C NMR spectroscopy can be widely utilized for lignin characterization without a specific chemical treatment or decomposition of lignin.

Primary adenocarcinoma of the lacrimal sac with 5-year recurrence-free survival after radiation therapy alone: a case report.

Lacrimal sac tumors are rare, with approximately 800 cases reported worldwide; primary adenocarcinoma of the lacrimal sac is particularly rare. Although there is no established treatment strategy, surgical removal is generally performed. However, complete removal often requires extensive resection, including orbital exenteration and lateral rhinoplasty, which is highly invasive and creates significant cosmetic issues.

Reverse pupillary block associated with pigment dispersion syndrome after in-the-bag intraocular lens implantation.

A 61-year-old man with high myopia who had received a systemic α1A-adrenoceptor antagonist had phacoemulsification and in-the-bag intraocular lens implantation in the right eye. One day postoperatively, marked pigment dispersion in the anterior chamber, posterior bowing of the iris, and iridodonesis were noted associated with a subsequent elevation in intraocular pressure (IOP). Pharmacological pupil dilation was effective in reducing pigment dispersion and IOP, and laser peripheral iridotomy was performed to alleviate posterior bowing of the iris.

Quantitative evaluation of regular and irregular corneal astigmatism in patients having overnight orthokeratology.

Purpose: To quantitatively assess changes in regular and irregular corneal astigmatism in patients having overnight orthokeratology.

Setting: Matsumoto Eye Clinic, Ibaraki, Japan.

Methods: A prospective study was conducted of 64 eyes of 39 patients having overnight orthokeratology for myopia.