Background The mesenchymal stem cells (MSCs) were used to repair tissue injury. However, the treatment effect was not satisfactory. We investigated whether lncRNA MIR155HG could promote survival and migration of MSCs under oxidative stress, which mimics in vivo environments. Furthermore, we studied the protective effect of exosomes secreted by MSCs transfected with MIR155HG on endothelial cells. This study aimed to determine whether exploiting MSCs and exosomes modified with lncRNA MIR155HG would exert synergistic therapeutic effect to attenuate vein graft intimal hyperplasia more effectively. Methods Lentivirus containing lncRNA MIR155HG overexpressing vector was packaged and used to infect MSCs. Then, CCK-8 assay, flow cytometry, Transwell assay, and Elisa assay were used to assess the functional changes of MSCs with overexpressed MIR155HG (OE-MSCs). Furthermore, the associated pathways were screened by Western blot. MIR155HG-MSCs-derived exosomes (OE-exo) were collected and co-cultured with human umbilicus vein endothelial cell (HUVEC). We validated the protective effect of OE-exo on HUVEC. In vivo, both MSCs and exosomes modified with MIR155HG were injected into a vein graft rat model via tail vein. We observed MSCs homing and intimal hyperplasia of vein graft using a fluorescent microscope and histological stain. Results Our study found that lncRNA MIR155HG promoted proliferation, migration, and anti-apoptosis of MSCs. NF-κB pathway took part in the regulation process induced by MIR155HG. OE-exo could enhance the activity and healing ability of HUVEC and reduce apoptosis. In vivo, OE-MSCs had a higher rate of homing to vascular endothelium. The combined treatment with OE-MSCs and OE-exo protected vascular endothelial integrity, reduced inflammatory cell proliferation, and significantly attenuated intimal hyperplasia of vein graft. Conclusion LncRNA MIR155HG could promote the survival and activity of MSCs, and reduce the apoptosis of HUVECs using exosome delivery. Exploiting MSCs and exosomes modified with MIR155HG could attenuate vein graft intimal hyperplasia more effectively and maximize the surgical effect.

Tool wear and breakage detection technologies are of vital importance for the development of automatic machining systems and improvement in machining quality and efficiency. The monitoring of integral spiral end milling cutters, however, has rarely been investigated due to their complex structures. In this paper, an image acquisition system and image processing methods are developed for the wear and breakage detection of milling cutters based on machine vision. The image acquisition system is composed of three light sources and two cameras mounted on a moving frame, which renders the system applicable in cutters of different dimensions and shapes. The images captured by the acquisition system are then preprocessed with denoising and contrast enhancing operations. The failure regions on the rake face, flank face and tool tip of the cutter are extracted with the Otsu thresholding method and the Markov Random Field image segmentation method afterwards. Eventually, the feasibility of the proposed image acquisition system and image processing methods is demonstrated through an experiment of titanium alloy machining. The proposed image acquisition system and image processing methods not only provide high quality detection of the integral spiral end milling cutter but can also be easily converted to detect other cutting systems with complex structures.

Background: There are several controversies regarding the surgical approach for patients with coronary atherosclerotic heart disease (CAHD) complicated with moderate ischemic mitral regurgitation (IMR). Methods: A retrospective study was performed among 115 patients divided into two groups. Clinical and echocardiographic parameters, including perioperative indexes and follow ups, degree of stenosis in the coronary arteries, and cardiac function index, were analyzed. Patients who died in the hospital due to complications during the perioperative period were defined as the deterioration group (deterioration of coronary artery bypass grafting, CABG vs. deterioration of coronary artery bypass grafting combined with mitral valve surgery, CABG+MVS: N = 7, 58.3% vs. N = 5, 41.7%), whereas the remaining patients were defined as the rehabilitation group (rehabilitation of CABG vs. rehabilitation of CABG+MVS: N = 52, 50.5% vs. N = 51, 49.5%). Data were compared between the rehabilitation of the CABG and CABG+MVS groups to explore the predictors for surgical method selection. Results: Postoperative patients who died during hospitalization were excluded (N = 12). At 1-year follow up, there were 52 patients in the CABG rehabilitation group and 51 in the CABG+MVS rehabilitation group. During the follow-up period, 10 patients died (rehabilitation of CABG vs. rehabilitation of CABG+MVS: N = 7, 13.7% vs. N = 3, 5.8%). Nevertheless, the difference was not statistically significant. The logistic regression analysis identified four independent factors when choosing the surgical modality: prior-myocardial infarction (prior-MI), preoperative atrial fibrillation (pre-AF), and the stenotic degree of the left circumflex (LCX) and left main (LM) arteries. Conclusions: Prior-MI, pre-AF, and the degree of stenosis in LCX and LM could influence the choice of surgical method. This study provided new insights into the treatment of CAHD with moderate IMR.

Background: In patients treated by heart transplantation, the index of microcirculatory resistance (IMR) has been found to have predictive potential for subsequent acute allograft rejection (AAR) and long-time cardiac events. When consulting related literature, the studies mostly were single-center with small sample sizes. The question of whether IMR can be utilized as a predictive biomarker is becoming increasingly contentious. To confirm the predictive efficacy of IMR, researchers did a systematic review and meta-analysis. Method: From inception to April 2022, PubMed, EMBASE, Cochrane Library, Web of Science, Ovid, ProQuest, and Scopus systematically were searched. The results were presented as pooled ratio rate (RR) with 95% confidence intervals (CI). Assessment of the quality, heterogeneity analyses, and publication bias analysis also were performed. Results: A total of 616 patients were studied in five trials. There were significant differences in subsequent AAR (RR = 4.08; 95% CI: 2.69~6.17; P = 0.000) or long-time cardiac events (RR=2.14; 95% CI: 1.44~3.19; P = 0.000) between IMR-high and IMR-low patients in the forest plots. Patients treated with heart transplantation in the high IMR group had better predictive efficacy than the low IMR group. Conclusions: High IMR could predict the events of subsequent AAR and cardiac events after heart transplantation. This will help reduce the occurrence of adverse events and personalize treatment for patients.

Anomalous pulmonary veins drain into the right side of the left atrium is an uncommon variety of anomalous pulmonary venous return. Rarely, anomalous pulmonary venous drainage combined with cor triatriatum and atrial septal defect.We presented the imaging findings of a male patient who had anomalous pulmonary venous drainage which has not previously been described.