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Background Light‐initiated chemiluminescent assays (LICA) are homogeneous assays that are sensitive, specific, and free of separation and washing steps and have high throughput and high precision. Methods In this research, we developed a competitive method by LICA to achieve accurate quantification of estradiol (E2) in human serum. E2 competed with estriol (E3) for binding to anti‐human E2 antibodies. E3 was linked to biotin via bovine serum albumin as a linker. As this assay used competition between the labeled tracer and the analyte, an increase in E2 concentration will cause a signal decrease. Results The expected detection range of E2 was 20‐5000 pg/mL. The analytical and functional sensitivities were 7.16 and 13.7 pg/mL, respectively. The intra‐ and inter‐assay coefficients of variation were both below 15%, and the recovery rate ranged from 97.5% to 106.8%. The interference rates ranged from −3.6% to 5.4% and met detection requirements for E2 in hyperbilirubinemia, hemolysis, and lipemia in clinical samples. In addition, the cross‐reactivity rates between E2 and structural analogs and some reproductive hormones varied from 1.9% to 10.6% which showed that LICA is highly specific for E2. Moreover, our results showed high accordance with the IMMULITE 2000 (y = 0.6695x + 47.92, r2 = .843) and VIDAS systems (y = 1.099x − 821.5, r2 = .9392). Conclusion Our data show that the LICA, which is easy to automate, is a promising technique for quantification of E2 in human serum and could be used for clinical detection.

Quantification of testosterone serves an important role in the differential diagnosis of androgen-related endocrine diseases. Mass spectrometry exhibits higher accuracy and lower variability than immunoassays, especially at low testosterone concentrations. The present study developed and validated an isotope dilution ultra-performance liquid chromatography tandem mass spectrometry method for determination of human serum testosterone. The serum was equilibrated with an isotopic internal standard and treated with acidic buffer to release hormones from their binding proteins. Testosterone was extracted via two serial liquid-liquid extractions. In the first stage, the lipid fractions from an acidic buffer solution were isolated using ethyl acetate and n-hexane. The organic phase was evaporated and reconstituted in a basic buffer solution. In the second stage, the polar impurities of n-hexane extraction were removed. Total testosterone in serum was quantified via ultra-performance liquid chromatography tandem mass spectrometry in multiple reaction monitoring mode with positive electrospray ionization. The coefficient of variation of the method for intra-and inter-assay was 2.13% (1.40-2.77%) and 3.44% (3.06-3.66%), respectively. The recovery ranged from 94.32 to 108.60% for different samples. The limit of detection was 0.50 ng/dl and the linear range was from 1.00 to 1,000.00 ng/dl. In addition, the extraction efficiency in three different levels of quality control of the serum ranged from 85.02 to 93.29%. Moreover, structural analogues were investigated and were not indicated to affect the quantification of testosterone. The present method may enable quantification of testosterone in a clinical setting with high precision and accuracy.

Determination of human cytomegalovirus IgG (HCMV IgG) level is of great importance in the diagnosis of HCMV infections. In this study, a novel, double antigen sandwich homogeneous immunoassay‐based light‐initiated chemiluminescent assay (LICA) for measuring HCMV IgG serum levels was developed. This sandwich LICA for HCMV IgG was performed by incubating serum samples with HCMV pp150 protein coated with chemibeads, streptavidin‐coated sensibeads, and biotinylated HCMV pp150 protein. The working conditions of this assay were optimized and the correlation between the results of the LICA and enzyme‐linked immunosorbent assay was evaluated. As a homogeneous immunoassay, this sandwich LICA could accurately and rapidly determine the serum levels of HCMV IgG with a high‐throughput. Thus, this newly developed assay could be a useful analytical tool in the clinical diagnosis of HCMV infections.

Refactoring has become an effective approach to convert sequential programs into concurrent programs. Many refactoring algorithms and tools are proposed to assist developers in writing high-performance concurrent programs. Although researchers actively conduct surveys on refactoring, we are not aware of any survey that summarizes, categorizes and discusses concurrency-oriented refactoring. To this end, this paper presents a survey that investigates how refactoring assists with concurrent programming. To the best of our knowledge, this paper is the first survey that summarizes the state-of-the-art, concurrency-oriented refactoring. First, we design six research questions addressing the concurrent structure, programming language, performance improvement and consistency evaluation. Second, we answer these questions by examining the related papers and then present the results to show how refactoring provides support for concurrent programming after a decade of development, such as transforming the concurrent structures, supporting parallel language, and improving performance. Finally, we summarize the related works and present the future trends.