Necroptosis was found in a rat ischemia/reperfusion injury flap model / 中华医学杂志(英文版)

BACKGROUND@#Necroptosis is a new form of cell death that has been identified as a third pathway causing cell death. In this study, necrostatin-1 (Nec-1) was used to determine whether necroptosis exists in a rat ischaemia/reperfusion injury flap model.@*METHODS@#In this study, twenty male Sprague-Dawley rats were divided randomly into two groups: a control group (CTL group) and a Nec-1 group. Each abdominal skin flap underwent 3 h of ischaemia and then reperfusion. Fifteen minutes before and after reperfusion, phosphate buffer saline (PBS) was administered intraperitoneally to the CTL group, while Nec-1 was administered intraperitoneally to the Nec-1 group. Twenty-four hours after reperfusion, the whole flap was divided equally into 54 sections. Flap blood perfusion was measured. One sample was taken randomly from each row. Morphological changes, apoptosis, receptor-interacting protein-1 (RIP-1) expression and caspase-3 activity were observed and detected. The measurements between the two groups were compared with the independent t-test, and a P value of <0.05 was considered statistically significant.@*RESULTS@#Compared to flaps in the CTL group, flaps in the Nec-1 group showed longer survival rates, better blood perfusion and less inflammatory infiltration. The total flap area considered to have survived was 70.88 ± 10.28% in the CTL group, whereas 80.56 ± 5.40% of the area was found to be living in the Nec-1 group (Nec-1 vs. CTL, t = -2.624, P < 0.05). For some rows, there were significant differences in cell apoptosis between the two groups, the apoptosis index (AI) in rows "9 cm", "7 cm", "6 cm" and "5 cm" was significantly lower in the Nec-1 group than that in the CTL group (Nec-1 vs. CTL, P < 0.05). RIP-1 expression was much lower in the Nec-1 group than that in the CTL group in rows "5 cm" to "9 cm" (Nec-1 vs. CTL, P < 0.05). No significant differences in caspase-3 activity were found.@*CONCLUSION@#According to the results, necroptosis was present in a rat abdominal ischaemia/reperfusion injury flap model.

Hyperbaric oxygen therapy improves the effect of keloid surgery and radiotherapy by reducing the recurrence rate / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

OBJECTIVE@#Keloids are exuberant cutaneous scars that form due to abnormal growth of fibrous tissue following an injury. The primary aim of this study was to assess the efficacy and mechanism of hyperbaric oxygen therapy (HBOT) to reduce the keloid recurrence rate after surgical excision and radiotherapy.@*METHODS@#(1) A total of 240 patients were randomly divided into two groups. Patients in the HBOT group (O group) received HBOT after surgical excision and radiotherapy. Patients in the other group were treated with only surgical excision and radiotherapy (K group). (2) Scar tissue from recurrent patients was collected after a second operation. Hematoxylin and eosin (H&E) staining was used to observe keloid morphology. Certain inflammatory factors (interleukin-6 (IL-6), hypoxia-inducible factor-1α (HIF-1α), tumor necrosis factor-α (TNF-α), nuclear factor κB (NF-κB), and vascular endothelial growth factor (VEGF)) were measured using immunohistochemical staining.@*RESULTS@#(1) The recurrence rate of the O group (5.97%) was significantly lower than that of the K group (14.15%), P<0.05. Moreover, patients in the O group reported greater satisfaction than those in the K group (P<0.05). (2) Compared with the recurrent scar tissue of the K group, the expression levels of the inflammatory factors were lower in the recurrent scar tissue of the O group.@*CONCLUSIONS@#Adjunctive HBOT effectively reduces the keloid recurrence rate after surgical excision and radiotherapy by improving the oxygen level of the tissue and alleviating the inflammatory process.

Analysis of Clinical Features and Factors Related to Treatment Decision for Hospitalized Patients With Mitral Regurgitation / 中国循环杂志

Objectives:To observe the clinical features and factorsrelated to treatment decision for hospitalizedpatients with mitral regurgitation (MR). Methods:A total of 3 450 consecutivepatients with transthoracic echocardiography (TTE) confirmed moderate to severe MR admitted in our hospital from 2014-01-01 to 2015-12-31 were enrolled. Base on therapeutic method, the patients were divided into 2 groups:Surgery group, n=1 845 and Medication group, n=1 605. The baseline data including TTE results were collected, clinical features were compared between 2 groups and factors related to treatment decision were analyzed. Results:Mean age of this patient cohort was (54.8±13.8) years including 26.99% (931/3 450) patients aged ≥65 years. The most common etiology was primary MR, 324 (9.39%) patients were asymptomatic at admission and decreased left ventricular ejection fraction (LVEF) was evidenced in 55.28% (1 907) patients. Total in-hospital mortality was 0.75% (26). Compared with Medication group, the patients in Surgery group were younger ([52.65±12.01] years vs [57.39±15.25] years), prevalence of severe MR (56.69% vs 26.79%) and primary MR (89.49% vs 39.00%), as well as LVEF value ([61.62±9.20] % vs [48.00±17.53] %) were higher (all P＜0.001).Logistic regression analysis indicated that age (OR=0.561, 95% CI 0.503-0.627), MR etiology (OR=3.062, 95% CI 2.565-3.654), MR grade (OR=0.103, 95% CI 0.085-0.126) and LVEF (OR=2.478, 95% CI 2.147-2.860) were the determinants for treatmentdecision making in hospitalized patients with moderate to severe MR. Conclusions:In this patient cohort, there are considerable proportion of aged patients with moderate to severe MR. Primary MRis the major etiology. 46.52% patients received conservative therpay instead of surgery, older age,secondary MR, moderate MR and decreased LVEF are the major reasons for choosing conservative therapy in this patient cohort.

Hemodynamics-based numerical comparison between two options of modified B-T shunt / 医用生物力学

Objective To analyze and compare hemodynamic features of two different options for modified B-T shunt (MBTS) surgery, namely end-to-side(ETS) and side-to-side (STS), so as to provide references for clinical treatment of single ventricle heart defect syndrome. MethodsThe real geometric model was reconstructed by medical images obtained from a patient with hypoplastic left heart syndrome (HLHS); MBTS surgery was simulated through virtual operations; a lumped parameter model (LPM) was constructed based on physiological data of the patient; the post-operational boundary conditions of computational fluid dynamics (CFD) models (namely STS model and ETS model) were predicted based on the LPM; numerical simulation was conducted on two CFD models by using finite volume method. Results Flow details and wall shear stress distributions were all obtained for two models. The mean oscillatory shear index (OSI) of ETS model and STS model in part of pulmonary arteries was 3.058×10-3 and 13.624×10-3, respectively, while the energy loss was 116.5 and 94.8 mW, respectively, and blood flow rate ratios of left pulmonary artery to right pulmonary artery (RRPA/LPA) were 0.8 and 1.72, respectively. Conclusions There were nearly no differences between two CFD models in energy loss, which led to a relatively small impact on the surgery. The STS model had a more balanced pulmonary artery blood perfusion and a smaller mean OSI in part of pulmonary arteries, therefore, the STS model was superior to the ETS model. This study provides an important theoretical support and reference for treating patients with HLHS.

Numerical study on multiscale simulation for hemodynamics of systemic-pulmonary shunt procedure based on lattice Boltzmann method / 医用生物力学

Objective Based on time-coupled multiscale coupling algorithm, to simulate the hemodynamics after systemic-pulmonary shunt procedure on single ventricular patient so as to obtain the local three-dimensional (3D) fluid field and global hemodynamic information before and after surgery. MethodsFirstly, the 0D-3D coupled multiscale hemodynamic model of systemic-pulmonary shunt procedure was established based on the lumped parameter model (0D) before surgery and the shunt model (3D), then the 0D-3D interface coupling condition and the time coupling algorithm were discussed. Secondly, the multiscale simulation of 3D CFD (computational fluid dynamics) model coupled with 0D lumped parameter model was realized based on lattice Boltzmann method. Finally, the multiscale simulation results were compared with patient’s 0D simulation results to study the hemodynamic changes before and after surgery. Results The global hemodynamic change and local 3D flow pattern were obtained by this multiscale simulation. The pulmonary blood flow distribution ratio was increased from 32.21% to 57.8%. Conclusions The systemic-pulmonary shunt procedure can effectively increase the blood supply of pulmonary circulation by implanting the shunt between the systematic circulation and pulmonary circulation. The geometrical multiscale method can effectively simulate both the coarse global and detailed local cardiovascular hemodynamic changes, which is of great significance in pre-operation planning of cardiovascular surgery.