Collagen 1 gel may improve the regenerative capacity of minced adult and preosteoarthritic cartilage.

PURPOSE: Minced cartilage implantation (MCI) is an evolving technique for the treatment of osteochondral lesions. It was hypothesised that mincing of cartilage may affect chondrocyte viability and phenotype and that embedding in collagen 1 gel results in an improved outcome. The objective of this study was to evaluate the impact of cartilage mincing and whether collagen 1 gel mediates beneficial effects on the chondrocyte phenotype and viability. METHODS: Human cartilage samples from 11 patients undergoing total knee arthroplasty were collected and minced according to the MCI protocol. Minced cartilage was cultured for 1 week with and without embedding in collagen 1 gel and was compared with unminced cartilage flakes as control. Quantitative reverse transcription-PCR and immunohistochemical staining for the chondrocyte marker genes SOX9, COL2, ACAN, COL10 and MMP13 were used to examine the chondrocyte phenotype. Cell death was assessed by the terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. RESULTS: Increased chondrocyte cell death of cultured cartilage after mincing was observed. Chondrocytes from minced cartilage exhibited significantly decreased expression and protein levels of homeostatic and hypertrophic chondrocyte markers. Embedding in collagen 1 gel showed no positive effect on viability. However, remarkable is the increased expression of ACAN and the preserved protein level of SOX9 in the collagen 1-embedded minced cartilage. CONCLUSIONS: This study shows that the mincing of cartilage leads to increased chondrocyte death and decreased expression of chondrocyte phenotypic marker genes after 7 days. The use of collagen 1 gel may improve the stability of the phenotype, which needs to be further elucidated. LEVEL OF EVIDENCE: Level III (therapeutic).

Determination of Ethanol in Food by Enzymatic Method Enzytec™ Liquid Ethanol, Collaborative Study: Final Action 2017.07.

BACKGROUND: Enzytec™ Liquid Ethanol was approved as AOAC Official MethodSM2017.07 First Action in September 2017 and is now further characterized by a collaborative study using the manual and automated version of the test. METHOD: It is applicable to quantify ethanol in diluted or undiluted kombucha, fruit juices, vegetable juices, and alcohol-free beer samples around 0.5% ABV within 20 min using two ready-to-use reagents and measurement of absorbance at 340 nm. RESULTS: The overall relative reproducibility standard deviation across a wide concentration range for kombucha was calculated to be 6.99% by modeling the reproducibility standard deviation by the mean concentration for each of the six kombucha pairs by a linear regression. Analysis of juices and beer showed an overall higher variation with an estimated overall RSD(R) value by regression of 10.1%. Mean recovery of aqueous ethanol reference solutions tested by each participant was between 100 and 103%. CONCLUSIONS: The data obtained by this collaborative study show that the EnzytecTMLiquid Ethanol is suitable to quantify ethanol from matrices representing important alcohol-free liquid food categories. HIGHLIGHTS: The EnzytecTMLiquid Ethanol was approved as AOAC Method 2017.07 Final Action.