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Background: Quantitative flow ratio (QFR) is an estimate of fractional flow reserve (FFR) and is derived from 3-dimensional quantitative coronary angiography. The DILEMMA score is an angiographic technique developed to predict FFR. Unlike other diastolic indices such as instantaneous wave-free ratio (iFR), diastolic pressure ratio (dPR) and dPR25-75, neither QFR nor DILEMMA score require pressure wires. This study sought to compare the diagnostic performance of QFR, diastolic indices and DILEMMA score to predict FFR. Method(s): Between January 2010 and December 2013, patients who underwent invasive coronary angiography and FFR assessments were retrospectively studied. iFR and dPR were derived from FFR pressure tracings. QFR was computed using commercial software. Result(s): Eighty-five lesions (25% FFR significant) were included in this study. Median FFR was 0.88 (0.81-0.92). QFR (rs=0.801), iFR (rs=0.710), dPR (rs=0.716), dPR25-75 (rs=0.715) and DILEMMA score (rs=-0.623) significantly correlated with FFR (P<0.001). QFR <=0.8 had a specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of 95%, 86%, 86% and 95% respectively of predicting significant FFR (P<0.001). Receiver-operating characteristic (ROC) analysis revealed the AUC to predict significant FFR for QFR (0.947), iFR (0.880), dPR (0.883), dPR25-75 (0.880) and DILEMMA score (0.916) were not significantly different. However, QFR was a better predictor of FFR than iFR (0.947 vs. 0.770, P<0.01). Conclusion(s): QFR had excellent correlation and accuracy as measured against FFR. When compared to other diastolic indices and DILEMMA score, QFR performed at least as well as the other indices. QFR predicts FFR better than it predicts iFR. QFR is a convenient tool to assess significance of coronary stenosis and a reliable alternative to pressure-wire based indices. Prospective studies are required to investigate the performance and cost-effectiveness of QFR when independently used

In this study, the effects of salinity fluctuation on gene expression patterns in ovary and hepatopancreas of Litopenaeus vannamei were analyzed. The expression level of vitellogenin in the ovaries were significantly, markedly, and slightly, inhibited respectively in the hepatopancreas after brooders were transferred from 30‰ to 20‰ or 40‰ salinity for 4 days. The expression levels of the development of germ cell related genes Dmc1, proliferating cell nuclear antigen (PCNA) and cyclophilin A were significantly reduced at 20‰ or 40‰ salinity. The transcript level of shrimp ovarian peritrophin (SOP) was significantly reduced at 20‰ salinity, and the expression level of ovary specific gene mucin-5 AC was significantly higher at 40‰ salinity. Four stress related genes, cytoplasmic carbonic anhydrase (LvCAc), Na+/K+-ATPase alpha subunit (LvNK), V-H+-ATPase subunit A (LvVH), and heat shock protein 90 (LvHSP90), were significantly up-regulated at 40‰ salinity in the ovaries. In the hepatopancreas, the transcript level of fatty acid synthase (LvFAS) was significantly inhibited under 40‰ salinity. The mRNA levels of stress related genes LvNK, LvVH, and LvHSP90, were significantly lower at 40‰ salinity. Results indicated that changes in salinity caused transcription inhibition of germ cell and ovarian development related genes, and the expression patterns of stress related genes in the ovaries and hepatopancreas were quite different.