RÉSUMÉ
Objective:To explore the predictive value of systemic immune-inflammation index (SII) and small and dense low-density lipoprotein-cholesterol (sdLDL-C) on contrast-induced acute kidney injury (CI-AKI) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing emergency percutaneous coronary intervention (PCI).Methods:This retrospective analysis included 674 STEMI patients who underwent emergency PCI in Affiliated Hospital of Xuzhou Medical University from November 2019 to October 2021, all patients were divided into a training cohort ( n=450) and validation cohort ( n=224) at a ratio of 2∶1 according to the chronological sequence. The patients in the training cohort were further divided into CI-AKI group ( n=92) and non-CI-AKI group ( n=358). Information at admission and emergency blood biochemical indexes were collected, and the SII was calculated. Multifactorial logistic regression analysis was used to explore the independent factors influencing the occurrence of CI-AKI in STEMI patients undergoing emergency PCI in the training cohort and a predictive model was established. Receiver operating characteristic (ROC) curve and Hosmer-Lemeshow test were used to evaluate the model discrimination and calibration. Results:The prevalence of CI-AKI was 20.4% (92/450). Age, proportion of women, sdLDL-C, urea, baseline creatinine, uric acid, neutrophil count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and SII were significantly higher in the CI-AKI group than in the non-CI-AKI group (all P<0.05), and left ventricular ejection fraction (LVEF), high-density lipoprotein cholesterol, estimated glomerular filtration rate (eGFR) and lymphocyte count were significantly lower in the CI-AKI group than in the non-CI-AKI group (all P<0.05). The results of multifactorial logistic regression analysis showed that age ( OR=1.046, P=0.001), LVEF ( OR=0.916, P<0.001), sdLDL-C ( OR=4.754, P<0.001), uric acid ( OR=1.012, P=0.007), eGFR ( OR=0.994, P=0.002), and lnSII ( OR=2.471, P<0.001) were independent determinants of CI-AKI after emergency PCI in STEMI patients. ROC curve analysis showed that area under the curve (AUC) for the diagnosis of CI-AKI was 0.688 with a sensitivity of 73.9% and specificity of 61.5% for the SII cut-off point of 1 179.07×10 9/L. The AUC for the diagnosis of CI-AKI was 0.709 with a sensitivity of 65.2% and specificity of 77.4% for the sdLDL-C cut-off point of 1.147 mmol/L. The AUC for the diagnosis of CI-AKI was 0.847 with a sensitivity of 88.0% and a specificity of 70.6% for the combination of SII and sdLDL-C with age, LVEF, uric acid and eGFR. The Hosmer-Lemeshow test (χ2=6.913, P=0.546) proved the goodness of fit of the model. Conclusions:SII and sdLDL-C have significant clinical value in the prediction of CI-AKI. SII and sdLDL-C combined with age, LVEF, uric acid and eGFR could further improve the predictive efficacy of CI-AKI.
RÉSUMÉ
HSPC144 is a newly identified gene in human CD34(+) hematopoietic stem/progenitor cells. In this work, we have expressed and purified the 225-residue protein from Escherichia coli BL21 (DE3) and identified a stable fragment HSPC144-P (residues 44-225) by limited proteolysis method. The HSPC144-P fragment exhibits high stability with a little increase of secondary structure percentage as compared with the full-length protein. We anticipated that the N-terminally truncated protein possesses a more compact structure. By sequence analysis, the proteolytic fragment shares a great similarity with DUF589 domain, a previously identified domain with unknown function. This novel domain is highly conserved in Thy28 proteins and is worthy of structural and functional studies. We have subcloned this homologous domain from HSPC144 protein and purified to homogeneity for structure analysis. The (15)N and (15)N/(13)C-labeled DUF589 domain samples have been prepared successfully and determination of the NMR structure is in progress.