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Zhou Weiyan,Deng Yuhang,Zhao Haijian,Zhang Chuanbao 대한진단검사의학회 2022 Annals of Laboratory Medicine Vol.42 No.4
Background: Accurate measurements of serum insulin and C-peptide are needed for the therapy and classification of diabetes. This study investigated the status of serum insulin and C-peptide measurements in China by analyzing the results of five pooled serum samples measured in 94 laboratories. Methods: Patient serum samples were pooled into five groups according to insulin and C-peptide concentrations and measured in 94 laboratories using different measurement systems. The inter- and intra-laboratory %CV as well as inter- and intra-measurement system %CV were calculated to assess the status of insulin and C-peptide measurements. To verify whether the disagreement between laboratories was due to different calibrators, as reported in previous studies, one low-level and one high-level sample extracted from the five pooled serum samples were used to recalibrate clinical measurement systems. Results: The mean intra-laboratory, intra-measurement system, inter-laboratory, and inter-measurement system %CVs were 2.7%, 4.8%, 21.8%, and 22.4%, respectively, for insulin and 2.3%, 6.7%, 16.4%, and 24.5%, respectively, for C-peptide. The inter- and intra-laboratory %CVs for insulin decreased with increasing concentration. After recalibration with low- and high-level samples, the mean inter-measurement %CV decreased from 22.4% to 17.2% for insulin and from 24.5% to 5.7% for C-peptide. Conclusions: The intra-laboratory and intra-measurement system imprecision values are satisfactory for serum insulin and C-peptide measurements. However, the results from laboratories using different measurement systems were not comparable, and there is still much work needed to achieve the standardization or harmonization of serum insulin and C-peptide measurements.
Songlin Yu,Weiyan Zhou,Xinqi Cheng,Qinghui Meng,Honglei Li,Li’an Hou,Jun Lu,Shaowei Xie,Qian Cheng,Chuanbao Zhang,Ling Qiu 대한진단검사의학회 2019 Annals of Laboratory Medicine Vol.39 No.4
Background: Accurate serum total thyroxine (TT4) measurement is important for thyroid disorder diagnosis and management. We compared the performance of six automated immunoassays with that of isotope-diluted liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) as the reference method. We also evaluated the correlation of thyroid stimulating hormone (TSH) with TT4 measured by ID-LC-MS/MS and immunoassays. Methods: Serum was collected from 156 patients between October 2015 and January 2016. TT4 was measured by immunoassays from Abbott (Architect), Siemens (ADVIA Centaur XP), Roche (E601), Beckman-Coulter (Dxi800), Autobio (Autolumo A2000), and Mindray (CL-1000i), and by ID-LC-MS/MS. Results were analyzed using Passing–Bablok regression and Bland–Altman plots. Minimum requirements based on biological variation were as follows: a mean bias of ≤4.5% and total imprecision (CV) of ≤3.7%. Results: All immunoassays showed a correlation >0.945 with ID-LC-MS/MS; however, the slope of the Passing–Bablok regression line varied from 0.886 (Mindray) to 1.23 (Siemens) and the intercept from -12.8 (Siemens) to 4.61 (Mindray). Only Autobio, Beckman-Coulter, and Roche included the value of one in the 95% confidence interval for slope. The mean bias ranged from -10.8% (Abbott) to 9.0% (Siemens), with the lowest value noted for Roche (3.5%) and the highest for Abbott (-10.8%). Only Abbott and Roche showed within-run and total CV ≤3.7%. Conclusions: Though all immunoassays correlated strongly with ID-LC-MS/MS, most did not meet the minimum clinical requirement. Laboratories and immunoassay manufacturers must be aware of these limitations.
A Novel Algorithm for Green Citrus Detection based on the Reticulate Grayladder Feature
Mingjun Wang,Jun Zhou,Weiyan Shang,Rufu Hu,Xuefeng Wang,Liang Gong 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.10
Immature green citrus fruit detection using conventional color images is a challenging task due to fruit color similarity with the background, partial occlusion, varying illumination and shape irregularity. Therefore, most existing green fruits detection algorithms, which use color as the main discriminant feature, have a low recognition rate and a high rate of false positives. In this manuscript, we developed a novel Green Citrus fruit Detection algorithm based on the proposed Reticulate Grayladder Feature (GCDRGF), which contained 4 major steps: First, an 8-graylevel image was generated by the preprocessing steps of median filtering, histogram-based equalization and 8-graylevel discretization of the input raw image. Secondly, reticulate grayladders were obtained by a multidirectional scanning on the 8-graylevel image, and rule-based pseudo-grayladder removal strategies were used to remove false positives of target grayladders. Thirdly, grayladder clustering and fruit location fitting were used to generate candidate regions for target fruits. Finally, majority voting was performed to determine the results of candidate regions based on the analysis of apparent features and recticulate grayladders within candidate regions. The experimental results proved the effectiveness of the proposed reticulate grayladder feature and the corresponding detection algorithm with respect to various illuminant and imaging conditions. Compared with the existed eigenfruit algorithm, our algorithm has a higher rate of successful recognition and a lower rate of false positives, which helps to greatly improve the productivity of robotic operations.
Li, Dandan,Peng, Weiyan,Wu, Bin,Liu, Huan,Zhang, Ruizhen,Zhou, Ruiqin,Yao, Lijun,Ye, Lin Korean Society for Molecular and Cellular Biology 2021 Molecules and cells Vol.44 No.4
Metallothionein (MT1M) belongs to a family of cysteinerich cytosolic protein and has been reported to be a tumor suppressor gene in multiple cancers. However, its role in esophageal carcinoma carcinogenesis remains unclear. In this study, MT1M expression was correlated with tumor type, stage, drinking and smoking history, as well as patient survival. We also studied the regulation and biological function of MT1M in esophageal squamous cell carcinoma (ESCC). We have found that MT1M is significantly downregulated in ESCC tissues compared with adjacent non-cancer tissues. Furthermore, restoration of expression by treatment with the demethylation agent A + T showed that MT1M downregulation might be closely related to hypermethylation in its promoter region. Over-expression of MT1M in ESCC cells significantly altered cell morphology, induced apoptosis, and reduced colony formation, cell viability, migration and epithelial-mesenchymal transition. Moreover, based on reactive oxygen species (ROS) levels, a superoxide dismutase 1 (SOD1) activity assay and protein analysis, we verified that the tumor-suppressive function of MT1M was at least partially caused by its upregulation of ROS levels, downregulation of SOD1 activity and phosphorylation of the SOD1 downstream pathway PI3K/AKT. In conclusion, our results demonstrated that MT1M was a novel tumor-suppressor in ESCC and may be disrupted by promoter CpG methylation during esophageal carcinogenesis.
Deng Yuhang,Liu Qingxiang,Liu Zhenni,Zhao Haijian,Zhou Weiyan,Zhang Chuanbao 대한진단검사의학회 2022 Annals of Laboratory Medicine Vol.42 No.5
Background: To identify candidate external quality assessment (EQA) materials for normetanephrine and metanephrine measurements, we assessed the commutability of eight processed human plasma samples. The agreement between routine assays and the candidate reference measurement procedure (cRMP) was also evaluated. Methods: Fifty-three clinical samples and eight processed plasma samples were prepared. The processed samples included pooled and individual plasma samples spiked with pure normetanephrine and metanephrine and non-spiked pooled and individual plasma samples. The clinical and processed samples were subjected to four routine isotope dilution tandem mass spectrometry assays and cRMP. Commutability was assessed based on two approaches recommended by the CLSI and International Federation of Clinical Chemistry (IFCC). Passing–Bablok regression and Bland–Altman analysis were used to evaluate the agreement between the routine assays and cRMP. Results: The commutability results of the CLSI approach were better than those of the IFCC approach. For the CLSI approach, spiked individual plasma samples and spiked high-concentration pooled plasma samples were commutable for all routine assays for both analytes. The non-spiked pooled plasma sample was commutable for two out of four routine assays for metanephrine and three out of four routine assays for normetanephrine. The agreement between the routine assays and the cRMP was satisfactory, except for one routine assay showing significant bias. Conclusions: High-concentration spiked pooled plasma samples and spiked individual plasma samples are candidate EQA materials for normetanephrine and metanephrine measurements.
Deng Yuhang,Zhang Chao,Wang Jing,Zeng Jie,Zhang Jiangtao,Zhang Tianjiao,Zhao Haijian,Zhou Weiyan,Zhang Chuanbao 대한진단검사의학회 2023 Annals of Laboratory Medicine Vol.43 No.4
Background: Serum C-peptide results from various routine methods used in China are highly variable, warranting well-performing methods to serve as an accuracy base to improve the harmonization of C-peptide measurements in China. We developed an accurate isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC–MS/MS) method for serum C-peptide measurement and explored its use in harmonization. Methods: After protein precipitation with ZnSO4 solution, C-peptide was extracted from serum samples by anion-exchange solid-phase extraction and quantified by ID-LC–MS/MS in positive ion mode. The precision and analytical recovery of the ID-LC–MS/MS method were assessed. Seventy-six serum samples were analyzed using the ID-LC–MS/MS method and six routine immunoassays. Ordinary linear regression (OLR) and Bland-Altman (BA) analyses were conducted to evaluate the relationship between the ID-LC–MS/MS method and routine immunoassays. Five serum pool samples assigned using the ID-LC–MS/MS method were used to recalibrate the routine assays. OLR and BA analyses were re-conducted after recalibration. Results: The within-run, between-run, and total precision for the ID-LC–MS/MS method at four concentrations were 1.0%–2.1%, 0.6%–1.2%, and 1.3%–2.2%, respectively. The analytical recoveries for the ID-LC–MS/MS method at three concentrations were 100.3%–100.7%, 100.4%–101.0%, and 99.6%–100.7%. The developed method and the immunoassays were strongly correlated, with all R2 >0.98. The comparability among the immunoassays was substantially improved after recalibration. Conclusions: The performance of the ID-LC–MS/MS method was carefully validated, and this method can be used to improve the harmonization of serum C-peptide measurements in China.