Follow-up study evaluating the long term outcome of chondromimetic in the treatment of osteochondral defects in the knee

© 2020 by the authors. Scaffolds are thought to be a key element needed for successful cartilage repair treatments, and this prospective extension study aimed to evaluate long-term structural and clinical outcomes following osteochondral defect treatment with a cell-free biphasic scaffold. Structural outcomes were assessed using quantitative 3-D magnetic resonance imaging (MRI) and morphological segmentation to determine the percentage of defect filling and repair cartilage T2 relaxation times, and clinical outcomes were determined with the modified Cincinnati Rating System, and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Seventeen subjects with osteochondral defects in the knee were treated with ChondroMimetic scaffolds, from which 15 returned for long-term evaluation at a mean follow-up of 7.9 - 0.3 years. The defects treated were trochlear donor sites for mosaicplasty in 13 subjects, and medial femoral condyle defects in 2 subjects. MRI analysis of scaffold-treated defects found a mean total defect filling of 95.2 - 3.6%, and a tissue mean T2 relaxation time of 52.5 - 4.8 ms, which was identical to the T2 of ipsilateral control cartilage (52.3 - 9.2 ms). The overall modified Cincinnati Rating System score was statistically significant from baseline (p = 0.0065), and KOOS subscales were equivalent to other cartilage repair techniques. ChondroMimetic treatment resulted in a consistently high degree of osteochondral defect filling with durable, cartilage-like repair tissue at 7.9 years, potentially associated with clinical improvement

Multiple mechanisms contribute to fluorometry signals from the voltage-gated proton channel

Abstract Voltage-clamp fluorometry (VCF) supplies information about the conformational changes of voltage-gated proteins. Changes in the fluorescence intensity of the dye attached to a part of the protein that undergoes a conformational rearrangement upon the alteration of the membrane potential by electrodes constitute the signal. The VCF signal is generated by quenching and dequenching of the fluorescence as the dye traverses various local environments. Here we studied the VCF signal generation, using the Hv1 voltage-gated proton channel as a tool, which shares a similar voltage-sensor structure with voltage-gated ion channels but lacks an ion-conducting pore. Using mutagenesis and lipids added to the extracellular solution we found that the signal is generated by the combined effects of lipids during movement of the dye relative to the plane of the membrane and by quenching amino acids. Our 3-state model recapitulates the VCF signals of the various mutants and is compatible with the accepted model of two major voltage-sensor movements

Fényemittáló maleinimid tartalmú polimerek előállítása és vizsgálata

Fluoreszcens tulajdonságokkal rendelkező maleimid tartalmú alapláncokat szintetizáltunk. Az előállított monomereket (akril-származékok) gyökös módszerrel polimerizáltuk. A fluoreszcens termékeket tisztítottuk és részletesen karakterizáltuk NMR, GPC és tömegspektrometriás mérésekkel. Az elvégzett optikai vizsgálatok kimutatták, hogy az előállított monomerek és polimerek, az oldat elkészítésénél használt oldószer polaritásától függően, zöld vagy sárga fényt emittálnak