Objective To establish normal reference ranges for serum cystatin C (Cys C)in relatively healthy middle-aged and elderly(＞50 years)Chinese individuals.Methods A total of 1087 candidates were consecutively selected and serum Cys-C levels were measured by transmission turbidimetry.Frequency analysis and histogram were used to establish the 95％ confidence reference range according to methods provided by CLSI (C28-A2).Results Based on the definition and verification procedures for clinical laboratory reference ranges(CLSI C28-A2,second edition),Cys-C levels of 1087 participants fell within the range of 0.30-1.55 mg/L;Male participants had higher serum Cys-C levels than female participants(Z=-10.19,P＜0.01).The serum Cys-C level increased with age,regardless of gender(R =0.600,P＜ 0.01).Differences in Cys-C levels between age groups were statistically significant (x2=411.17,P＜ 0.01).The reference ranges of normal serum Cys-C levels for different age groups (50-,55-,60-,65-,70-,75-,) were 0.42-0.98mg/L,0.45-1.04mg/L,0.47-1.34mg/L,0.46-1.38mg/L,0.61-1.33mg/L,0.61-1.28 mg/L,respectively,for males,and 0.39-0.94mg/L,0.42-1.01mg/L,0.40-0.91mg/L,0.46-1.03mg/L,0.57-1.04mg/L,0.55-1.27mg/L,respectively,for females.Conclusions This study established preliminary normal serum Cys-C reference ranges for healthy middle-aged and elderly(＞ 50 years)individuals in this region,which can serve as parameters for disease diagnosis and treatment evaluation.

Bioluminescence is a widespread phenomenon in nature, and luminescent organisms can be found both on land and in the ocean. Among them, luciferase based bioluminescence systems have been widely studied, inspiring the exploration of genetic and epigenetic aspects and the development of a series of related assays for in vivo and in vitro studies. This paper summarizes the recent developments of luciferase based bioluminescence assays in terms of bioluminescence systems, types of luciferases, and the development and application of luciferase bioluminescence assays.

Fluorescence-guided surgery (FGS) with tumor-targeted imaging agents, particularly those using the near-infrared wavelength, has emerged as a real-time technique to highlight the tumor location and margins during a surgical procedure. For accurate visualization of prostate cancer (PCa) boundary and lymphatic metastasis, we developed a new approach involving an efficient self-quenched near-infrared fluorescence probe, Cy-KUE-OA, with dual PCa-membrane affinity. Cy-KUE-OA specifically targeted the prostate-specific membrane antigen (PSMA), anchored into the phospholipids of the cell membrane of PCa cells and consequently showed a strong Cy7-de-quenching effect. This dual-membrane-targeting probe allowed us to detect PSMA-expressing PCa cells both in vitro and in vivo and enabled clear visualization of the tumor boundary during fluorescence-guided laparoscopic surgery in PCa mouse models. Furthermore, the high PCa preference of Cy-KUE-OA was confirmed on surgically resected patient specimens of healthy tissues, PCa, and lymph node metastases. Taken together, our results serve as a bridge between preclinical and clinical research in FGS of PCa and lay a solid foundation for further clinical research.