[Establishment of an Iron-overloaded Mouse Model with Tuberculosis and Analysis of the Iron Metabolism Index].

Objective To establish a mouse model of exogenous iron overload combined with tuberculosis(TB). Methods C57BL/6N mice were divided into negative control, low-, medium-, and high-dose iron groups and received intraperitoneal injection of iron dextran at 0, 3.75, 7.50, and 15.00 mg/dose(3 times/week for 4 weeks), respectively.After 4 weeks, the organ morphology and body weight of the mice were evaluated.The content of serum iron, ferritin, transferrin, and transferrin receptor was determined by ELISA.Heart, liver, spleen, lung, kidney, and small intestine were analyzed for tissue iron content and iron deposition pathology.Mycobacterium tuberculosis(Mtb)standard strain H37Rv was injected via tail vein to infect the mice receiving moderate-dose iron to establish an iron-overloaded mouse model of active TB.HE staining and Mtb culture were employed to analyze tuberculous lesions and bacterial loads of lung, spleen and liver tissues. Results The weight gain percentages of mice in the negative control, low-, medium-, and high-dose iron groups were 25.47%, 25.22%, 24.74%, and 21.36%, respectively, which was significantly lower in the high-dose group than in the negative control(F=17.235, P=0.027), low-dose(F=15.206, P=0.031), and medium-dose(F=11.061, P=0.036)groups.Liver had the highest iron content, followed by spleen, kidney, and small intestine.The iron content in heart and lung tissues of the low-dose group had no significant difference compared with those of the negative control group(F=19.023, P=0.715;F=23.193, P=0.902).Serum iron and ferritin in the iron-overloaded mice increased in a dose-dependent manner, while transferrin and transferrin receptor had no significant changes.HE and Prussian blue staining showed that the iron-overloaded mice had different degrees of iron deposition in tissues and high-dose iron caused liver and kidney damage.The lung(F=23.227, P=0.017), spleen(F=19.023, P=0.021), and liver(F=17.392, P=0.009)of the iron-overloaded mice with TB had a significantly shorter time of bacterial culture than those of the TB-infected mice without iron overload.The lung(F=21.012, P=0.007), spleen(F=20.173, P=0.002), and liver(F=19.091, P=0.005)of the iron-overloaded mice with TB had significantly higher bacterial loads than those of the TB-infected mice without iron overload. Conclusions The exogenous iron-overloaded mouse model with similar symptoms to patients with clinical iron overload can be established by intraperitoneal injection of medium-dose(7.50 mg/dose, 3 times/week for 4 weeks)iron dextran.Mtb injection through the tail vein can help construct a mouse model of iron overload combined with active TB.

Five-Year Outcomes of Bioresorbable Stent Therapy for Coronary Heart Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Background: The efficacy of bioresorbable vascular scaffolds (BVS) compared to metallic stents for the treatment of coronary heart disease remains controversial. The analysis of clinical outcomes at five years following the initial treatment has yet to be reviewed. This study sought to assess the five-year outcomes in randomized controlled trials of BVS in the treatment of coronary heart disease using a systematic review and meta-analysis. Methods: A systematic database search was conducted from their inception to June 30th, 2023 using various Medical Subject Headings (MeSH) terms including: "Coronary Disease", "Bioresorbable stent", "Randomized controlled trials". Results: After a rigorous selection process, a total of five high-quality articles were finally included in this study. Each trial demonstrated a low risk of bias. After 5 years, bioresorbable stents showed outcomes similar to conventional metal stents in terms of cardiac mortality. However, they were inferior in terms of lesion revascularization rates, in-stent thrombosis rates, target lesion failure, target vessel failure, and myocardial infarction. Conclusions: While bioresorbable stents are comparable to metallic stents in terms of cardiac mortality rates, they exhibit significant drawbacks that warrant clinical consideration.