Cardiovascular diseases are among the primary causes of decreased quality of life as well as mortality of hemodialysis patients with end-stage renal disease. The aim of the present study was to evaluate the predictive value of the red blood cell distribution width (RDW)-to-platelet ratio (RPR) and neutrophil-to-lymphocyte ratio (NLR) regarding the occurrence or development of cardiovascular events in hemodialysis patients, as well as the prognostic value of this metric. A total of 219 hemodialysis patients with cardiovascular events (HCE group) and 276 hemodialysis patients with no cardiovascular events (HNCE group) were enrolled in the present study. The clinical characteristics and laboratory parameters on admission, including RDW, as well as neutrophil, lymphocyte and platelet counts, were recorded. The NLR and RPR were increased in the HCE group compared with those in the HNCE group and there was a positive association between the NLR or RPR and the incidence of cardiovascular events in hemodialysis patients. In the receiver operating characteristics curve analysis, the area under the curve of the RPR for predicting cardiovascular events in hemodialysis patients was 0.88, while that for the NLR was 0.84. The sensitivity and specificity of the RPR for predicting cardiovascular events in hemodialysis patients were 0.87 and 0.82 respectively, and for the NLR, they were 0.75 and 0.79, respectively. The RPR was an independent risk factor for the prognosis regarding cardiovascular events in hemodialysis patients. In addition, the NLR and RPR were correlated with brain natriuretic peptide (BNP), cardiac troponin I (cTnI), creatine kinase isoenzyme-MB (CK-MB), and associated with ST segment changes in HCE patients. In conclusion, it was possible to predict the incidence of cardiovascular events in hemodialysis patients using the NLR and RPR, while the RPR had a better sensitivity and specificity than the NLR. The RPR was an independent risk factor for the prognosis regarding cardiovascular events in hemodialysis patients. These routinely available parameters should be considered as novel diagnostic markers for the occurrence and development of cardiovascular events in hemodialysis patients and their prognosis.

Construction of a random ssDNA sublibrary is an important step of the aptamer screening process. The available construction methods include asymmetric PCR, biotin–streptavidin separation, and lambda exonuclease digestions, in which PCR amplification is a key step. The main drawback of PCR amplification is overamplification increasing nonspecific hybridization among different products and by‐products, which may cause the loss of potential high‐quality aptamers, inefficient screening, and even screening failure. Cycle number optimization in PCR amplification is the main way to avoid overamplification but does not fundamentally eliminate the nonspecific hybridization, and the decreased cycle number may lead to insufficient product amounts. Here, we developed a new method, “asymmetric emulsion PCR,” which could overcome the shortcomings of conventional PCR. In asymmetric emulsion PCR, different templates were separated by emulsion particles, allowing single‐molecule PCR, in which each template was separately amplified, and the nonspecific hybridization was avoided. Overamplification or formation of by‐products was not observed. The method is so simple that direct amplification of 40 or more cycles can provide a high‐quality ssDNA library. Therefore, the asymmetric emulsion PCR would improve the screening efficiency of systematic evolution of ligands by exponential enrichment.