ObjectiveTo investigate the effect of serum C-peptide level on the progression of liver fibrosis in patients with type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD). MethodsA total of 484 patients with T2DM who were admitted to Department of Geriatrics, The Second Hospital of Lanzhou University, from December 2018 to July 2020 were enrolled, and according to the results of abdominal ultrasound examination, they were divided into simple T2DM group with 107 patients and T2DM+NAFLD group with 377 patients. According to NAFLD fibrosis score, the patients with T2DM and NAFLD were divided into fibrosis exclusion subgroup （T2DM+F0） with 136 patients, uncertain subgroup (T2DM+F1) with 146 patients, and fibrosis subgroup (T2DM+F2) with 95 patients. Medical history data and laboratory markers were collected. The chi-square test was used for comparison of categorical data; the t-test or the Mann-Whitney U test was used for comparison of continuous data, and a one-way analysis of variance or the Kruskal-Wallis H test was used for comparison between multiple groups; a logistic regression analysis was used to explore the risk factors for the progression of liver fibrosis; the receiver operating characteristic (ROC) curve was used to analyze the clinical value of serum C-peptide in predicting and diagnosing the progression of liver fibrosis. ResultsCompared with the simple T2DM group, the T2DM+NAFLD group had a significant increase in C-peptide level (Z=-6.040,P＜0.001); compared with the T2DM+F1 and T2DM+F0, the T2DM+F2 had significantly higher C-peptide level ［2.89 (1.84-3.77) vs 1.97 (1.12-2.65)/1.87 (1.25-2.68), H=36.023,P＜0.001) and rate of fasting C-peptide (56.84% vs 23.29%/24.27%, χ2=37.583,P＜0001). The logistic regression analysis showed that C-peptide (OR=1.435, 95% confidence interval: 1.227~1.678， P＜0.001) was a risk factor for liver fibrosis in patients with T2DM and NAFLD, and the ROC curve analysis also showed that C-peptide had great significance in predicting liver fibrosis in such patients, with an area under the ROC curve of 0.814, a sensitivity of 642%, a specificity of 897%, and a Youden index of 0.539 at the optimal cut-off value of 2.405 ng/ml. ConclusionC-peptide is an independent risk factor for the progression of liver fibrosis in patients with T2DM and NAFLD.

Objective To explore the application and nursing care of patients with severe burn patients with scar skin treated by ultrasound-guided PICC catheter placement. Methods Twelve patients with burn area of more than 95% were treated with intravenous catheter placement of PICC under the condition of scar hyperplasia skin with the help of ecg. Results Ten patients in elbow basilic vein catheterization by PICC disposable puncture, 1 cases of catheter in the right upper arm of the basilic vein into vascular sheath scar after guidewire dilating the skin in place leading to vascular sheath damaged anterior guidewire failed in bending catheter, to your left arm to venous catheter success, 1 cases of catheter for initial puncture puncture into the insufficient experience in successful puncture needle when the guide wire back because of scar skin relaxation will not needle guide wire fixing the wire with a lead to two times of puncture, 12 cases of catheter tip position by X-ray showed in the superior vena cava under 1/3, indwelling time ranged from-11 months of March, in the retention period without related complications. Conclusions It is feasible and advantageous for the application of PICC catheter in the treatment of severe burn patients with scar skin.

convalescents, and to screen for broad-spectrum neutralizing antibodies against the SARS-CoV-2 RBD. Methods Using biotinylated RBD as a molecular probe, flow cytometry was employed to perform single-cell sorting of B cells from peripheral blood mononuclear cells (PBMCs) of convalescents. The obtained B cells were lysed and subjected to reverse transcription, followed by nested PCR amplification of the heavy and light chains of antibodies was conducted using random primers. The amplified products were cloned into corresponding expression vectors, and the respective matched heavy-light chain plasmids were co-transfected into 293F cells for expression. Monoclonal antibodies were then purified using Protein A column chromatography. Neutralization experiments were conducted with the wild-type (WT) pseudovirus, and antibodies with IC50<0.1 μg/mL were selected for further testing of neutralizing breadth and potency against the wild-type (WT), Beta variant (B.1.351), Delta variant (B.1.617.2), and currently prevalent pseudovirus strains (XBB, BA.5, BF.7). Results A total of 21 RBD-specific monoclonal B cells were obtained from two recovered patients, resulting in the isolation of 13 pairs of antibody light/heavy chains. Nine antibodies were successfully expressed, with P1-A1, P1-B6, and P1-B9 exhibiting IC50 values below 0.1 μg/mL against the pseudovirus of the wild-type strain (WT). Specifically, P1-B6 effectively neutralized the wild-type strain (WT), Beta variant (B.1.351), and Delta variant (B.1.617.2), with IC50 values reaching 0.01 μg/mL. P1-B9 demonstrated effective neutralization against the wild-type strain (WT), Beta variant (B.1.351), Delta variant (B.1.617.2), and Gamma variant (P.1) pseudoviruses, with IC50 values of 0.42 μg/mL, 0.63 μg/mL, 0.28 μg/mL, and 2.50 μg/mL, respectively. Additionally, P1-B6 exhibited good neutralization against BA.5 and BF.7 pseudoviruses, with IC50 values of 0.06 μg/mL and 0.09 μg/mL, respectively. Conclusions Infection with the SARS-CoV-2 WT strain can induce the generation of neutralizing antibodies with broad-spectrum activity. Generating these broadly neutralizing antibodies does not require an excessively high somatic hypermutation. The obtained antibodies can be used as candidates for SARS-CoV-2 diagnosis and prevention.