【摘要】 目的 采用多柔比星（doxorubicin，DOX）制备心肌损伤动物模型，评价各种检测心功能变化方法的意义。 方法 14只新西兰大白兔，DOX耳缘静脉注射，每周3 mg/kg，共10周。分别于给药前、第4周末及实验结束时测定血清肌钙蛋白Ⅰ（cTnI）和脑钠肽（BNP）水平，彩色多普勒超声心动图检测心功能变化，并观察心肌组织病理形态学改变及心肌细胞凋亡情况。 结果 使用DOX前后对比，血清cTnI和BNP浓度升高（Plt;0.05）；左室射血分数（LVEF）和左室短轴缩短率（LVFS）下降（Plt;0.05）；心肌组织病理显示心肌细胞出现不同程度的空泡变性与水肿，细胞间隙明显增宽，大量炎性细胞浸润。心肌细胞凋亡明显增加。 结论 结合心脏超声检查和血清cTnI、BNP指标检测可判断心肌损伤程度。【Abstract】 Objective To observe the changes of heart function caused by doxorubicin in rabbits. Methods A total of 14 New-Zealand white rabbits were intravenous-injected with doxorubicin with a dosage of 3 mg/kg intravenously once a week, and the accumulative dose was 30 mg/kg. Before the medication and at the 4th and 10th weekend after the medication, the serum levels of cardiac troponin I (cTnI) and brain natriuretic peptide (BNP) were measured; left ventricular ejection function (LVEF) and left ventricular fractional shortening (LVFS) were performed on the rabbits respectively. At the 10th weekend, the pathological changes of cardiac tissue and the apoptosis of myocardial cell were detected. Results The levels of cTnI and BNP significantly increased (Plt;0.05), and the LVEF and LVFS markedly decreased (Plt;0.05) after the administration of doxorubicin. Uneven vacuolar degeneration and edema of cardiocytes could be observed with a wide cell spaces and inflammatory cell infiltration in the histopathological slices. Conclusion The combined application of heart sonography with the detection of the serum levels of cTnI and BNP can evaluate the degree of myocardial damage of the rabbits models very well.
Objective To summarize the effectiveness of F-shaped screw fixation technique in treatment of Pauwels type Ⅲ femoral neck fractures. Methods Between January 2013 and December 2016, 43 patients with Pauwels type Ⅲ femoral neck fractures were treated with F-shaped screw fixation technique. There were 32 males and 11 females with an average age of 38.9 years (range, 20-55 years). The fractures located on the left side in 21 patients and on the right side in 22 patients. The cause of injury included traffic accident in 19 patients and falling from height in 24 patients. There were 25 patients of Garden type Ⅲ and 18 of Garden type Ⅳ. The time from injury to operation was 2-3 days (mean, 2.2 days). These data were recorded, including operative time, fluoroscopy time, postoperative hospital stay, quality of reduction, postoperative complications (nonunion, varus deformity, femoral neck shortening, avascular necrosis of femoral head, screws back-out), and Harris scores. Results The operative time was 28-45 minutes (mean, 37.5 minutes). The fluoroscopy time was 13-20 seconds (mean, 14.7 seconds). The postoperative hospital stay was 2-3 days (mean, 2.7 days). All incisions healed by first intention. All patients were followed up 18–58 months with an average of 38.7 months. All patients have anatomical reduction of fractures. Fracture healing occurred in 42 patients; the union time was 3-5 months with an average of 3.6 months. Nonunion occurred in 1 patient who was treated with total hip arthroplasty. Of the 42 patients with fracture healing, 11 cases had a femoral neck shortening, 9 cases had varus deformity, 3 cases had avascular necrosis of femoral head, and 8 cases had screws back-out. There was no significant difference in complication incidences between Garden type Ⅲ fractures and Garden type Ⅳ fractures (P>0.05). Conclusion Treatment of femoral neck fractures by using the F-shaped screw fixation technique, can achieve satisfactory effectiveness with less postoperative complication.
Hemifacial microsomia (HFM) is a developmental hypoplasia of one side of face and ear due to congenital hypoplasia. At present, the causes of HFM have not been completely clarified, the classification methods are diverse, and the diagnosis and treatment methods are complex. Through reviewing the relevant study on the treatment of HFM domestic and overseas in recent years, the possible etiology and corresponding clinical manifestations of the disease are analyzed, and the existing clinical classification methods, treatment strategies and latest research results are summarized.
ObjectiveThis study aims to study the effects and mechanism of resveratrol on hepatocellular carcinoma (HCC) cells through phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) axis.MethodsHepG2 cells at logarithmic growth stage were treated with different concentrations (0, 12.5, 25.0, and 50.0 μmol/L) of resveratrol, respectively. Then the proliferation of HepG2 cells was detected by the CCK8 method and real time cell anaIysis (RTCA) system, the expressions of signal molecules associated with PI3K/Akt axis was detected by the Western blot method, including PI3K p58, phosphorylation protein kinase B (p-Akt), total protein kinase B (t-Akt), and CyclinA2 protein.ResultsResveratrol had a significant inhibitory effect on the growth of HepG2 cells in a time and dosage dependent manner. After 48 h treatment of resveratrol to HepG2 cells, 50.0 μmol/L resveratrol inhibited the growth of HepG2 cells most significantly. Further, the RTCA system studies also found that resveratrol had a time and concentration dependent effect on the reduction of normalized cell index (NCI) in HepG2 cells. Flow cytometry results showed that, apoptosis rates of 12.5, 25.0, and 50.0 μmol/L group were higher than that of 0 μmol/L group. Compard with 0 μmol/L group, the expressions of PI3K p85, p-Akt, and CyclinA2 protein in HepG2 cells of 12.5, 25.0, and 50.0 μmol/L resveratrol group was significantly higher (P<0.05), although there was no significant effect of resveratrol on the expression of t-Akt in HepG2 cells (P>0.05).ConclusionsResveratrol might have anti-proliferation effects on HepG2 cells through PI3K p85/Akt signaling axis. This study could provide a novel idea for the treatment to HCC.
ObjectiveTo systematically review the early clinical prediction value of machine learning (ML) for cardiac arrest (CA).MethodsPubMed, EMbase, WanFang Data and CNKI databases were electronically searched to retrieve all ML studies on predicting CA from January 2015 to February 2021. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. The value of each model was evaluated based on the area under receiver operating characteristic curve (AUC) and accuracy.ResultsA total of 38 studies were included. In terms of data sources, 13 studies were based on public database, and other studies retrospectively collected clinical data, in which 21 directly predicted CA, 3 predicted CA-related arrhythmias, and 9 predicted sudden cardiac death. A total of 51 models had been adopted, among which the most popular ML methods included artificial neural network (n=11), followed by random forest (n=9) and support vector machine (n=5). The most frequently used input feature was electrocardiogram parameters (n=20), followed by age (n=12) and heart rate variability (n=10). Six studies compared the ML models with other traditional statistical models and the results showed that the AUC value of ML was generally higher than that in traditional statistical models.ConclusionsThe available evidence suggests that ML can accurately predict the occurrence of CA, and the performance is significantly superior to traditional statistical model in certain cases.