Background:As a major complication after orthotopic liver transplantation (OLT), the occurrence of acute kidney injury (AKI) is frequently defined by serum creatinine (Cr); however, the accuracy of commonly used blood urea nitrogen (BUN), uric acid (UA), and β2-microglobulin (β2-MG) remains to be explored. This retrospective study compared the accuracy of these parameters for post-OLT AKI evaluation.Methods:Patients who underwent OLT in three centers between July 2003 and December 2013 were enrolled. The postoperative AKI group was diagnosed by the Kidney Disease Improving Global Outcomes (KDIGO) criteria and classified by stage. Measurement data were analyzed using the t-test or Wilcoxon rank-sum test; enumerated data were analyzed using the Chi-square test or Fisher's exact test. Diagnostic reliability and predictive accuracy were evaluated using receiver operating characteristic (ROC) curve analysis.Results:This study excluded 976 cases and analyzed 697 patients (578 men and 119 women); the post-OLT AKI incidence was 0.409. Compared with the no-AKI group, the AKI group showed very significant differences in Model for End-stage Liver Disease score (14.74 ± 9.91 vs. 11.07 ± 9.54, Z = 5.404; P < 0.001), hepatic encephalopathy (45 [15.8%] vs. 30 [7.3%], χ2 = 12.699; P < 0.001), hemofiltration (28 [9.8%] vs. 0 [0.0%], χ2 = 42.171; P < 0.001), and 28-day mortality (23 [8.1%] vs. 9 [2.2%], χ2 = 13.323; P <0.001). Moreover, mean values of Cr, BUN, UA, and β2-MG in the AKI group differed significantly at postoperative days 1, 3, and 7 (all P < 0.001). ROC curve area was 0.847 of Cr for the detection of AKI Stage 1 (sensitivity 80.1%, specificity 75.7%, cutoff value 88.23 μmol/L), 0.916 for Stage 2 (sensitivity 87.6%, specificity 82.6%, cutoff value 99.9 μmol/L), and 0.972 for Stage 3 (sensitivity 94.1%, specificity 88.2%, cutoff value 122.90 μmol/L).Conclusion:The sensitivity and specificity of serum Cr might be a high-value indicator for the diagnosis and grading of post-OLT AKI.

A semi-lumped reconfigurable on-chip bandpass filter with GaAs pHEMT technology is presented in this paper. Three order tunable bandpass filter is designed with serial lumped capacitors, parallel resonators, and reconfigurable components. The operating bands are adjusted by field effect transistors and its corresponding gate bias circuits with GaAs technology. The semi-lumped topology, intending to reduce the size of the circuit, is employed to construct the parallel resonators, which are implemented with short-ended stubs and metal-insulator-metal capacitors. The equivalent circuit model is built to interpret the mechanism of the on-chip reconfigurable bandpass filter. Compared with the traditional tunable filters, an ultra-compactness feature and low insertion loss are obtained with the proposed design. The size of the on-chip filter is only 0.8×1.07 mm 2 , which is equivalent to 0.08×0.11 λ 2 g at 10 GHz. The presented filter is reconfigurable in two frequency bands, one is centered at 10 GHz with a fraction bandwidth (FBW) of 24.94% and the other is operated at 8.8 GHz with a FBW of 13.35%. The tuning range of the FBW is 30.6%. Good agreements are observed between the simulated and measured S-parameters. INDEX TERMS GaAs pHEMT, miniaturized, on-chip, reconfigurable bandpass filter, semi-lumped topology.

Objectives This multicenter retrospective study aimed to compare the effects of HES and gelatin (GEL) on the risk of post-OLT AKI. Method A total of 1,672 patients undergoing OLT were enrolled from major transplant centers in China between 2005 and 2013. These patients were divided into three groups: GEL, hydroxyethyl starch (HES), and GEL + HES group. Results There was no significant difference in the incidence of post-OLT AKI among the GEL, HES, and GEL + HES groups. The GEL + HES group had a lower incidence of stage II post-OLT AKI than the other two groups. Compared with patients receiving GEL, patients receiving HES did not harbor an increased risk of AKI. Our results showed that MELD score (adjusted odds ratio [OR], 1.579; 95% confidence interval [CI], 1.123–2.219; P = 0.009) and preoperative anemia (adjusted OR, 1.533; 95% CI, 1.212–1.939; P < 0.001) were independent risk factors for post-OLT AKI, and normal preoperative Scr level (vs abnormal; adjusted OR, 0.402; 95% CI, 0.222–0.729; P = 0.003) was independent protective factors for post-OLT AKI. Conclusion This large-scale multicenter retrospective study found that the intraoperative use of HES did not increase the overall incidence of post-OLT AKI in patients when compared with GEL, and whether to increase the risk of post-OLT AKI needs to be further explored.