【Objective】 To verificate the performance of enzyme-linked immunosorbent assay (ELISA) in blood screening laboratory. 【Methods】 The repeatability, precision, sensitivity, specificity, compliance, detection limit and anti-interference of ELISA items in the laboratory detection system were verified. 【Results】 The repeatability was 100%.The intra batch imprecision of each system was less than 10%, and the inter batch imprecision was less than 15%. The sensitivity, specificity and compliance were 100%, with the minimum detection limits of the two reagents at 0.75 NCU/mL and 0.25 NCU/mL respectively, The anti-interference met the requirements of the reagent manual. 【Conclusion】 The analysis of the performance verification data of ELISA test items will help continuously improve the performance of detection system and ensure the safety of clinical blood use.

Objective To investigate the changes in gastrointestinal hormones during the progression of liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD), and to provide a basis for digestive function impairment. Methods A prospective analysis was performed for 326 patients with NAFLD who attended the outpatient service and were hospitalized and treated in Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine from October 2018 to June 2020, and FibroTouch was used to measure liver stiffness measurement (LSM). According to the presence or absence of liver fibrosis, they were divided into non-liver fibrosis group (group A, 161 patients with LSM < 7.3 kPa) and liver fibrosis group (group B, 165 patients with LSM ≥7.3 kPa). According to the fibrosis degree, the patients were further divided into F0-1 group (LSM < 7.3 kPa), F2 group (7.3 kPa ≤LSM < 9.7 kPa), F2-3 group (9.7 kPa ≤LSM < 12.4 kPa), F3-4 group (12.4 kPa ≤LSM < 17.5 kPa), and F4 group (LSM ≥17.5 kPa). Related data were collected, including age, sex, liver function parameters, and gastrointestinal hormones. The independent samples t -test and the one-way analysis of variance were used for comparison of normally distributed continuous data between groups, and the nonparametric Mann-Whitney U test and the Kruskal-Wallis H test were used for comparison of non-normally distributed continuous data between groups. A Spearman correlation analysis was used to investigate the correlation between LSM and liver function parameters. Results Comparison of liver function and gastrointestinal hormones showed that there were significant differences between groups A and B in alanine aminotransferase (ALT) ( Z =-3.778, P < 0.001), aspartate aminotransferase (AST) ( Z =-3.320, P =0.001), gamma-glutamyl transpeptidase (GGT) ( Z =-3.040, P =0.002), cholecystokinin (CCK) ( t =-2.944, P =0.003), and lipopolysaccharide (LPS) ( Z =-2.317, P =0.020). There were significant differences in ALT ( χ 2 =23.113, P < 0.001), AST ( χ 2 =23.415, P < 0.001), ALP ( χ 2 =15.962, P =0.003), GGT ( χ 2 =20.172, P < 0.001), and CCK ( F =2.687, P =0.031) between the F0-1 group with 161 patients, the F2 group with 89 patients, the F2-3 group with 46 patients, the F3-4 group with 16 patients, and the F4 group with 14 patients. LSM was positively correlated with direct bilirubin, ALT, AST, alkaline phosphatase, and GGT ( r =0.128, 0.266, 0.225, 0.137, and 0.213, all P < 0.05). Conclusion Liver fibrosis progression in NAFLD can affect gallbladder contraction function and gastrointestinal function, and measurement of the serum levels of CCK and LPS has an important clinical value in the early diagnosis and treatment of digestive diseases related to gallbladder contraction function and gastrointe stinal function in NAFLD patients with liver fibrosis.

Objective To investigate whether the progression of liver fibrosis affects endothelial function in patients with nonalcoholic fatty liver disease (NAFLD), and to early identify the warning of cardiovascular diseases caused by endothelial dysfunction by liver fibrosis progression. Methods A total of 280 patients who attended the outpatient service or were hospitalized in Department of Liver Disease, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, from April 2019 to October 2020 were enrolled, and they were diagnosed with fatty liver disease by ultrasound and met the diagnostic criteria for NAFLD. General information and related serological markers were collected and recorded. FibroTouch technique was performed for the NAFLD patients diagnosed by ultrasound to record their fat attenuation parameter (FAP) and liver stiffness measurement (LSM), and according to LSM, the patients were divided into non-progressive fibrosis group (239 patients with LSM < 11 kPa) and progressive fibrosis group (41 patients with LSM ≥11 kPa) to analyze the association between liver fibrosis progression and endothelin-1 (ET-1)/nitric oxide (NO) in NAFLD. The t -test or the Mann-Whitney U test was used for comparison of continuous data between two groups, and the Spearman method was used for correlation analysis. Results There were no significant differences between the non-progressive fibrosis group and the progressive fibrosis group in the expression levels of ET-1( Z =-0.190, P =0.849) and NO( Z =-1.509, P =0.131), and there were significant differences between the two groups in body mass index (BMI), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) ( Z =-3.977, -4.162, -3.471, -3.201, -3.202, and -3.311, all P < 0.05). The Spearman analysis showed that LSM was not correlated with ET-1, NO, and NO/ET-1 ( r s =-0.046, 0.086, and 0.104, all P > 0.05). Further analysis of the correlation of ET-1 and NO with each index showed that ET-1 was not correlated with age, NO, ALT, AST, GGT, total cholesterol, TG, HDL-C, low-density lipoprotein cholesterol (LDL-C), FAP, and BMI ( r s =-0.017, 0.054, -0.067, -0.016, -0.031, 0.004, 0.051, -0.084, -0.030, 0.080, and 0.044, all P > 0.05), and NO was not correlated with age, ET-1, ALT, AST, GGT, total cholesterol, TG, HDL-C, LDL-C, FAP, and BMI ( r s =0.004, 0.054, 0.011, 0.052, 0.004, -0.051, -0.052, -0.012, -0.076, -0.013, and -0.021, all P > 0.05). Conclusion This study shows that liver fibrosis progression in NAFLD has no impact on ET-1 and NO, suggesting that fibrosis progression may have no influence on endothelial function.