Objective:To study the expression of miRNA-29c in type 1 diabetic patients with early nephropathy and its diagnostic value for early nephropathy.Methods:168 patients with type 1 diabetes who were treated in our hospital from Jan. 2019 to Mar. 2022 were retrospectively selected as the research subjects. According to the occurrence of nephropathy, they were divided into simple diabetes group (122 cases) and diabetic nephropathy group (46 cases). Serum miRNA-29c levels were detected by RT-PCR. The gender, age, course of disease, and serum miRNA-29c levels were compared between the two groups. Logistic regression was used to analyze the influencing factors of early nephropathy in patients with type 1 diabetes. The ROC curve was used to analyze the diagnostic value of miRNA-29c for early nephropathy in type 1 diabetes.Results:The course of disease, blood pressure (systolic blood pressure, diastolic blood pressure), HbA1c, TC and blood uric acid in early nephropathy group were higher than those in simple diabetes group, while albumin, total bilirubin and miRNA-29c were lower than those in simple diabetes group, and the difference was statistically significant ( P<0.05). Multivariate Logistic analysis showed: long disease duration ( OR=2.061, 95% CI=1.090-3.896), systolic blood pressure ( OR=1.143, 95% CI=1.023-1.279), diastolic blood pressure ( OR=1.151, 95% CI=1.022) -1.298), high HbA1c ( OR=1.317, 95% CI=1.049~1.653), high blood uric acid ( OR=1.306, 95% CI=1.028-1.659), low miRNA-29c ( OR=0.845,95% CI= 0.730-0.979) were the risk factors for early nephropathy in patients with type 1 diabetes ( P<0.05). ROC curve analysis showed that the cut-off value of miRNA-29c for the diagnosis of early renal disease was 0.952, the area under the curve (AUC) was 0.863 (95% CI: 0.801-0.925), and the sensitivity and specificity were 84.78% and 80.33%, respectively. Conclusion:Serum miRNA-29c in patients with early stage nephropathy of type 1 diabetes is in a low expression state, which is an influencing factor for early stage nephropathy in patients with type 1 diabetes, and has a good diagnostic value for early stage nephropathy.

Objective The oxidative damage of DNA can be caused by excessive levels of Reactive oxygen species(ROS).Monitoring of DNA oxidative damage enables effective evaluation of ROS damage effects.Although the detection of DNA damage effects based on microbial sensor allows quantitative analysis of oxidative damage,the ROS clearance mechanism existed in bacterial will affect the sensitive of detection.The work of this article is to knockout the key genes of ROS clearance mechanism and construct an antioxidant gene-knock-out microbial sensor.The microbial sensor can realize sensitive monitoring of DNA damage effects and then evaluates the damage effects of cells by ROS.Methods The antioxidant damage genes of bacterial ahpCF,katE and katG were knocked out by λ-Red homologous recombination and antioxidant gene-knockout microbial sensor was constructed.The nalidixic acid sodium salt and UV irradiation were used to characterize the performance for monitoring of DNA damage effects.Results The antioxidant gene-knockout microbial sensors ΔahpC,ΔahpCF/ΔkatEG and ΔahpCF/ΔkatE/ΔkatG were constructed successfully.The results showed that the microbial sensor ΔahpCF/ΔkatE/ΔkatGl had the highest sensitive of damage effects and the limit of detection for nalidixic acid sodium salt was 0.40 μmol/L.In addition,1.80 min of UV irradiation(254 nm)was sufficient to induce a significant fluorescent expression effect in the engineered bacteria.Conclusion In this article,antioxidant gene-knockout microbial sensors had been constructed to realize active and sensitive monitoring of DNA damage effects such as DNA damage reagents and UV irradiation.The sensors could provide an active,effective,and sensitive potential monitoring method for future evaluation of radiation effects in space.