Prediction of mortality among patients with chronic kidney disease:A systematic review

BACKGROUND Chronic kidney disease(CKD)is a common medical condition that is increasing in prevalence.Existing published evidence has revealed through regression analyses that several clinical characteristics are associated with mortality in CKD patients.However,the predictive accuracies of these risk factors for mortality have not been clearly demonstrated.AIM To demonstrate the accuracy of mortality predictive factors in CKD patients by utilizing the area under the receiver operating characteristic(ROC)curve(AUC)analysis.METHODS We searched Ovid MEDLINE,EMBASE,and the Cochrane Library for eligible articles through January 2021.Studies were included based on the following criteria:(1)Study nature was observational or conference abstract;(2)Study populations involved patients with non-transplant CKD at any CKD stage severity;and(3)Predictive factors for mortality were presented with AUC analysis and its associated 95%confidence interval(CI).AUC of 0.70-0.79 is considered acceptable,0.80-0.89 is considered excellent,and more than 0.90 is considered outstanding.RESULTS Of 1759 citations,a total of 18 studies(n=14579)were included in this systematic review.Eight hundred thirty two patients had non-dialysis CKD,and 13747 patients had dialysis-dependent CKD(2160 patients on hemodialysis,370 patients on peritoneal dialysis,and 11217 patients on non-differentiated dialysis modality).Of 24 mortality predictive factors,none were deemed outstanding for mortality prediction.A total of seven predictive factors[N-terminal pro-brain natriuretic peptide(NT-proBNP),BNP,soluble urokinase plasminogen activator receptor(suPAR),augmentation index,left atrial reservoir strain,C-reactive protein,and systolic pulmonary artery pressure]were identified as excellent.Seventeen predictive factors were in the acceptable range,which we classified into the following subgroups:predictors for the non-dialysis population,echocardiographic factors,comorbidities,and miscellaneous.CONCLUSION Several factors were found to predict mortality in CKD patients.Echocardiography is an important tool for mortality prognostication in CKD patients by evaluating left atrial reservoir strain,systolic pulmonary artery pressure,diastolic function,and left ventricular mass index.

Near-field launching and mapping unidirectional surface plasmon polaritons using an automated dual-tip scanning near-field optical microscope

The spatial distribution of electromagnetic fields emitted from the aperture tip of a scanning near-field optical microscope(SNOM), which is called the emission pattern, depends on the geometry of the apex and the material composition of the tip’s coating. In previous works, experimental measurements of the emission pattern from the aperture tip were performed mostly in the far field. Moreover, the corresponding theoretical models were also developed based on these far-field measurements. Here, we have used the automated dual-tip SNOM to systematically characterize the emission from the aperture tip in the near field. In this regard, we have considered three different pairs of excitation and detection tips with distinct geometries. The emission patterns of the excitation tips were mapped using detection tips. Unidirectional surface plasmon polaritons(SPPs) at the surface of a gold platelet were launched by an excitation tip and measured in the near field by the detection tip. The experimental results were numerically reproduced by means of the Bethe–Bouwkamp model. This work puts into evidence the applicability of the automated dual-tip SNOM as the only available characterization technique to measure the emission from aperture tips in the near field. The reported asymmetric SPP radiation patterns can find applications in photonic integrated circuits or in biological and chemical sensing.