Fluorescence-Lifetime-Sensitive Probes for Monitoring ATP Cleavage. Hammler Daniel,Marx Andreas,Zumbusch Andreas Chemistry (Weinheim an der Bergstrasse, Germany) Adenosine triphosphate (ATP) probes modified with fluorescence dyes that change their fluorescence properties upon cleavage are an interesting tool for monitoring enzymatic ATP turnover. As a readout parameter, fluorescence lifetime is attractive because it is nearly independent of concentration. In our study, we synthesised and investigated fifteen different ATP analogues, in which the fluorophores were attached to the γ-phosphate of ATP. All analogues showed distinctly different fluorescence lifetimes compared to the corresponding values of the free fluorophores. Both increases and decreases in fluorescence lifetime were observed upon attachment to ATP. To shed light on the photophysical processes governing the lifetime changes, we performed photoelectron spectroscopy in air (PESA) to determine HOMO energy levels and time-resolved fluorescence spectroscopy to obtain rate constants. We present evidence that fluorescence quenching in the compounds tested is dynamic and attributed to photoinduced electron transfer (PET), whereas fluorescence lifetime increases are caused by stacking interactions between chromophore and the nucleobase reducing non-radiative relaxation. Finally, we demonstrate that enzymatic cleavage of the ATP analogues presented can be followed by continuous monitoring of fluorescence lifetime changes. 10.1002/chem.201803234

Bilateral discoid medial Meniscus: Two case reports. Medicine RATIONALE:Discoid meniscus is an anatomical congenital anomaly more often found in the lateral meniscus. A discoid medial meniscus is a very rare anomaly, and it is difficult to diagnose a bilateral discoid medial meniscus because not all the discoid medial menisci are symptomatic. Herein, we report 2 cases of bilateral discoid medial meniscus. PATIENTS CONCERNS:Case1: a 23-year-old man presented with complaints of pain and occasional clicking of the right knee for 6 years, the left knee was asymptomatic. Case 2: a 51-year-old woman had a 1-month history of pain and a feeling of "giving away" in both knees. DIAGNOSES:Based on physical examination and magnetic resonance imaging (MRI) findings, they were diagnosed with bilateral discoid medial meniscal tears. INTERVENTIONS:Case 1: partial meniscectomy and reshaping were performed for the torn discoid medial meniscus of the right knee only. Case 2: partial medial meniscectomy and reshaping were performed for the torn discoid medial meniscus on both knees. OUTCOMES:The postoperative pain and the recovery of joint function were observed. The average follow-up time of 2 patients was 1 year. The Lysholm score of 2 patients was improved from 55 to 95 and 40 to 90 respectively. The pain of knee joint was relieved and the symptoms of disharmony were obviously improved. LESSONS:We recommend preservation of the discoid medial meniscus in asymptomatic patients. Meniscectomy and reshaping for injured discoid medial meniscus produces promising short-term results. 10.1097/MD.0000000000015182