Shear Wave Elastography in the Evaluation of Renal Parenchymal Stiffness in Patients With Chronic Kidney Disease: A Meta-Analysis.

Background: Chronic kidney disease (CKD) is a progressive loss of renal function, mainly due to hypertension, diabetes, and primary kidney disease. The histopathological findings are that of glomerulosclerosis, tubulointerstitial fibrosis and loss of renal parenchyma characterized. Therefrom, CKD can lead to higher morbidity and mortality. Patients with CKD have multiple risk factors, and the prevention work is complicated and arduous. Therefore, it is important to quantify the severity of CKD. The aim of this study is to investigate the value of shear wave elastography (SWE) in the evaluating renal parenchymal stiffness in patients with CKD. Methods: We carried out the systematic search of databases for publications in PubMed, Embase and Cochrane Library on SWE evaluating renal fibrosis in patients with CKD. The Endnote X9, STATA 16, Review Manager 5.3 and other software were used to sort out documents, extract, integrate and analyze data. Results: The outcomes were utilized to appraise the diagnostic accuracy of SWE and diagnose the CKD with renal fibrosis. A total of 405 patients were enrolled and their data analysis results were as follows: summary of sensitivity (S-SEN) 84% (95% confidence interval (CI): 80-87%); specificity (S-SPE) 80% (95% CI: 76-84%); summary of DLR (digital light radiography) positive (DLR-P) 4.29 (95% CI: 3.43 - 5.37); and DLR negative (DLR-N) 0.20 (95% CI: 0.16 - 0.25). The corresponding areas under the curves of diagnostic odds ratio (DOR) and summary receiver operating characteristic curve (SROC) were 21.50 (95% CI: 14.69 - 31.46) and 89% (95% CI: 86-92%), respectively. Conclusions: SWE is highly accurate and has clinical significance for evaluating renal fibrosis, especially when the shear modulus value is used as the threshold.

Removal of heavy metals from fly ash leachate using combined bioelectrochemical systems and electrolysis.

Based on environmental and energetic analysis, a novel combined approach using bioelectrochemical systems (BES) followed by electrolysis reactors (ER) was tested for heavy metals removal from fly ash leachate, which contained high detectable levels of Zn, Pb and Cu according to X-ray diffraction analysis. Acetic acid was used as the fly ash leaching agent and tested under various leaching conditions. A favorable condition for the leaching process was identified to be liquid/solid ratio of 14:1 (w/w) and leaching duration 10h at initial pH 1.0. It was confirmed that the removal of heavy metals from fly ash leachate with the combination of BESs and ER is feasible. The metal removal efficiency was achieved at 98.5%, 95.4% and 98.1% for Cu(II), Zn(II), and Pb(II), respectively. Results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) indicated that Cu(II) was reduced and recovered mainly as metal Cu on cathodes related to power production, while Zn(II) and Pb(II) were not spontaneously reduced in BESs without applied voltage and basically electrolyzed in the electrolysis reactors.

Degradation of p-nitrophenol in a BES-Fenton system based on limonite.

This study confirmed the feasibility of natural limonite working as the iron catalyst for the PNP wastewater treatment in the BES-Fenton system. After the start-up period of the BES-Fenton systems, air and limonite powder were injected into the cathode chamber as the original materials for manufacturing Fenton reagents of H2O2 and Fe(II) respectively. The experiment parameters like pH, external resistance, limonite dosage and initial PNP concentration were investigated in this research. The removal efficiency of PNP (0.25 mM) could achieve 96% in 6h under the optimal experimental conditions. A limonite dosage of 112 mg per 50 ml of PNP solution at 0.25 mM concentration each time could sustain 7 cycles of the BES-Fenton system operation with PNP removal efficiency >94%. This study suggests an efficiency and cost-effective approach for the PNP removal by using the natural limonite as the iron catalyst of the BES-Fenton system.

Bioelectrochemical recovery of ammonia-copper(II) complexes from wastewater using a dual chamber microbial fuel cell.

The cathodic reduction of complex-state copper(II) was investigated in a dual chamber microbial fuel cell (MFC). The inner resistance of MFC system could be reduced in the presence of ionizing NH(4)(+), however, mass transfer was hindered at higher ammonia concentration. Thermodynamic and electrochemical analyses indicated that the processes of complex dissociation and copper reduction were governed by the ratio of T[Cu]:T[NH(3)] and the pH of solution. The reduction of Cu(NH(3))(4)(2+) could be achieved via two possible pathways: (1) releasing Cu(2+) from Cu(NH(3))(4)(2+), then reducing Cu(2+) to Cu or Cu(2)O and (2) Cu(NH(3))(4)(2+) accepting an electron and forming Cu(NH(3))(2)(+), and depositing as Cu or Cu(2)O consequently. At initial concentration of 350 mg T[Cu] L(-1), copper removal efficiency of 96% was obtained at pH=9.0 within 12 h (with △Cu/△COD=1.24), 84% was obtained at pH=3.0 within 8 h (with △Cu/△COD=1.72). Cu(NH(3))(4)(2+) was reduced as polyhedral deposits on the cathode.