RESUMO
The effect of the antioxidant capacity of diet and its distribution across three meals on mortality risk among cancer patients remains unexplored. We aimed to prospectively investigate the association of dietary total antioxidant capacity (DAC) and its distribution across three meals with all-cause, cancer, and noncancer mortality among cancer survivors. We included 5,009 patients with cancer from the National Health and Nutrition Examination Survey conducted between 1999 and 2018. The adjusted hazard ratio (aHR) was estimated using the survey-weighted Cox proportional hazards model. During a median follow-up of 7.9 years, 1811 deaths, including 575 cancer-related deaths, were recorded. Among cancer survivors, compared with participants in the lowest quartile of total DAC from three meals, those in the highest quartile had a 24% decreased risk of noncancer mortality (aHR = 0.76, 95% confidence interval [CI]: 0.60-0.92), but not of all-cause and cancer mortality (each p trend >0.1). However, this association became insignificant for total DAC after excluding dinner DAC. In addition, higher dinner DAC rather than breakfast or lunch DAC was associated with a 21% lower risk of all-cause mortality (aHR = 0.79, 95% CI: 0.65-0.98) and 28% lower risk of noncancer mortality (aHR = 0.72, 95% CI: 0.57-0.90). Similar associations were found for ΔDAC (dinner DAC - breakfast DAC) with noncancer mortality (aHR = 0.56, 95% CI: 0.38-0.83), but DAC was not associated with cancer mortality (p trend >0.3). Among cancer survivors, total DAC from three meals was associated with reduced noncancer mortality, with the primary effect attributable to increased DAC intake from dinner. Our findings emphasize that DAC consumption from dinner should be advocated to reduce mortality risk in cancer survivors.
RESUMO
The level of uric acid is crucial to human health. Octahedral oxygen vacancy MnCo2O4/Ag (VO-MnCo2O4/Ag) nanozyme was successfully prepared by simple hydrothermal, calcination and self-reduction methods. VO-MnCo2O4/Ag nanozyme is rich in Mn2+/Mn3+ and CO2+/CO3+ redox electron pairs, large specific surface area and oxygen vacancies. VO-MnCo2O4/Ag nanozyme showed high uricase-like activity and peroxidase-like activity. At the same time, the SERS signal of the detected molecule could be significantly enhanced after the catalytic reaction of the VO-MnCo2O4/Ag nanozyme. The Km values of VO-MnCo2O4/Ag nanozyme for H2O2 and TMB were 0.04 mM and 0.027 mM respectively. Based on the uric acid oxidase-like and peroxidase-like activities of VO-MnCo2O4/Ag, we developed a label-free, sensitive, and reliable SERS uric acid detection system. The detection linear range of uric acid is 0.01 µM-1000 µM and the detection of limit is 7.8 × 10-9 M. The results show that the sensing system has good accuracy, sensitivity, selectivity, and stability. It can be applied to the determination of samples under different conditions. This study provides profound insights into the design of enzyme-like activity regulation and SERS properties regulation of nanozymes, provides guidance for the study of reaction kinetics and catalytic mechanism of nanozymes, and has broad application prospects in the field of nanozymes and SERS sensing analysis.
