Naphthalene-functionalized resorcinarene as selective, fluorescent self-quenching sensor for kynurenic acid.

Kynurenic acid is a by-product of tryptophan metabolism in humans, with abnormal levels indicative of disease. There is a need for water-soluble receptors that selectively bind kynurenic acid, allowing for detection and quantification. We report here the high-affinity binding of kynurenic acid in aqueous media to a resorcinarene salt receptor decorated with four flexible naphthalene groups at the upper rim. Experimental results from 1H NMR, isothermal titration calorimetry, and electronic absorption and fluorescence spectroscopies all support high-affinity binding and selectivity for kynurenic acid over tryptophan. The measured binding constant (K = 1.46 ± 0.21 × 105 M-1) is one order of magnitude larger than that observed with other resorcinarene receptors. The present host-guest system can be employed for sensory recognition of kynurenic acid. Computational studies reveal the key role of a series of cooperative attractive intra- and inter-molecular interactions contributing to an optimal binding process in this system.

Campylobacter rectus, an Uncommon Isolate of Multiple Splenic Abscesses, in a 79-Year-Old Chinese Woman With an Attempt at Conservative Management Followed by Operative Intervention: A Case Report.

Splenic abscesses are rare pathologic conditions in which Actinomyces and Campylobacter species are rarely isolated. We present a 79-year-old female with multiple splenic abscesses from unknown sources with both Actinomyces species and Campylobacter rectus being isolated. She was initially treated conservatively with percutaneous drainage but eventually needed splenectomy. To our knowledge, this is the first documented case of Campylobacter rectus isolated from a splenic abscess.

A Rare Recurrence of a Thyroglossal Duct Cyst Accompanied by Several Postoperative Complications in an Eight-Year-Old Boy: A Case Report.

A thyroglossal duct cyst (TGDC) is a fluid-filled mass in the neck resulting from the persistence of a duct from fetal development that typically regresses spontaneously. When it persists, it is most often removed in a surgical procedure known as a Sistrunk operation. This case study presents the intriguing case of an eight-year-old boy who presented to an otolaryngology clinic with both a recurrence of his TGDC, as well as several postoperative complications, after the Sistrunk operation was performed. After the initial procedure resulted in an incomplete removal of the TGDC, the patient was referred to Interventional Radiology for sclerotherapy. After several rounds of this treatment technique the cyst remnants still persisted along with their associated symptoms. Due to the very low likelihood of a recurrence being observed after surgical removal with subsequent sclerotherapy, the reappearance of the cyst raised several clinical questions. This report underscores the significance of a thorough evaluation and consideration of unique presentations when confronted with recurrent TGDCs.

An Unusual Presentation of a Black Discoloration on the Tympanic Membrane of a 10-Year-Old Girl: A Case Report.

This case report details an unusual presentation of unilateral tympanic membrane discoloration in a 10-year-old girl. The mysterious black discoloration was explored by various medical specialties, revealing a complex diagnostic journey due to the lack of evidence for this specific finding. Initially, the patient consulted her primary care physician after inserting a graphite pencil into her left ear canal, but without associated symptoms, she was considered to have returned to her baseline. The abnormal discoloration on the left tympanic membrane was first observed 10 months later, following diagnoses of two episodes of otitis media, otitis externa, and a middle ear effusion over three separate visits. By this time, the patient had been seen by four different medical professionals. The lesion was described as "a blackish discoloration in the posterior superior quadrant of the unperforated tympanic membrane near the umbo." This report underscores the need for thorough evaluation and consideration of atypical presentations when encountering unusual tympanic membrane discolorations.