Clinical indicators of SLE patients
Description
The SLE Disease Activity Index (SLEDAI-2000) was utilized to assess disease activity, with remission indicated by a score of 0-4, low activity by 5-9, moderate activity by 10-14, and high activity by a score exceeding 15. The following clinical data were collected: alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein (TP), albumin (ALB), total bilirubin (TBIL), direct bilirubin (DBIL), alkaline phosphatase (ALP), c-glutamyl transpeptidase (GGT), creatine kinase (CK), cholesterol (CHOL), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), UREA, serum Cr (Scr), uric acid (UA), SG, UREA/Scr, glucose (GLU), pH, proteinuria per 24h (24UTP), triglyceride per 24h (24UA), erythrocyte sedimentation rate (ESR), immunoglobulin A, G,M (IgA, IgG, or IgM), C3 , C4, platelet count (PLT), white blood cell count (WBC), antinuclear antibodies (ANA), and anti-double-stranded DNA antibodies (anti-dsDNA). Preparation of urine samples and analysis of 8-oxoGuo by HPLC–electrochemical detection (HPLC-ECD) The frozen midstream urine sample was incubated at 37 ℃ for 5 min, followed by centrifugation at 7500 g for 5 min at 4 ℃. For precise quantification in this study, the stable isotope-labeled 8-oxoGuo (8-oxoG-IS) served as an internal standard. The working solution was composed of 70% methanol, 30% water with 0.1% formic acid, and 5 mmol/L ammonium acetate. Subsequently, 200 μl supernatant was combined with 200 μl of working solution. Next, 10 μl of 8-oxo-[15N213C1]-Guo was included as an internal reference. Following 2-min vortex mixing, the sample was incubated at 37 °C. The sample was centrifuged at 12000 g for 15 min at 4 °C before analysis. The UHPLC-MS/MS was ultimately utilized to determinate the 8-oxoGuo in the sample. Agilent 6490 triple-quadrupole mass spectrometer (MS/MS) equipped with an Agilent 1290 UPLC system (Agilent Technologies, Inc., San Diego, CA, USA) and a JetStream ESI source and IFunnel (Agilent) were utilized for UHPLC-MS/MS. Chromatographic separation was performed using an Agilent C18 (3 μm, 3.00×100 mm) column at 35 ℃. The mobile phase was composed of solvent A, containing 0.1% formic acid and solvent B, consisting of methanol plus 0.1% formic acid. The flow rate was 0.4 mL/min, and the injection volume was 5 μl. The samples were maintained at a constant temperature of 4 ℃ to minimize sample solution loss. Early and late eluting components were disregarded to ensure the high-quality of the results. The Scr concentration was determined via a chemical analyzer (Model: 7600; Hitachi, Tokyo, Japan) in the Beijing Hospital. Urinary 8-oxoGuo level was normalized to urinary Cr level or urinary SG level prior to subsequent examination.