Objective: To observe the changes of heart-type fatty acid binding-protein(H-FABP) in the femoral vein(periphe ral blood) and urine of rats with myocardial infarction in different postmortem intervals. Methods: Acute myocardial infarction (AMI) was duplicated by ligating the anterior branch of the left coronary artery following the method of Johns in rats. Concentrations of H-FABP were detected with enzyme-linked immuno-sorbent assay (ELISA). Results: The concentrations of H-FABP in experiment group were obviously higher than that in control group. Along with the time, the concentrations of H-FABP in experiment group rose consistently, the concentration of H-FABP in 12 h group rose markedly, and it was obviously higher than in 48h that in 24h. The H-FABP concentrations in urine of the experiment group were obviouslyhigher than the one in control group. The urine concentrations of H-FABP in experiment group increased by wavy in postmortem intervals, the concentration of H-FABP in (6h) group was obviouslyhigher than that in 0h group, 12h and 24h postmortem, the H-FABP concentrations decreased, but still higher than that of 0h group and 48h group, the concentration of H-FABP rose markedly and washigher than 6h group. Conclusion: Affected by autolysis, the H-FABP concentrations of plasma and urine appeared abnormal raise and can not be used in postmortem diagnosis of AMI.

Objective:To explore the influencing factors of severe pneumonia in children with respiratory syncytial virus (RSV) infection.Methods:A retrospective case-control study was used to collect 210 children with RSV infected pneumonia admitted to Hebei Children′s Hospital from October 2017 to October 2020. Among them, 70 children with severe pneumonia were included in the severe pneumonia group, and 140 children with common pneumonia were included in the common pneumonia group; the baseline data and relevant laboratory indicators of the two groups were compared; Logistic regression was used to analyze the influencing factors of severe pneumonia in children infected with RSV.Results:The proportions of wheezing, congenital heart disease, respiratory failure, heart failure and pleural effusion of children in severe pneumonia group were higher than those in common pneumonia group, and the forced vital capacity (FVC) and forced expiratory volume in the first second (FEV 1) were lower than those in common pneumonia group (all P<0.05); the levels of C-reactive protein (CRP), CD8 + cells, RSV load and Beclin-1 in severe pneumonia group were higher than those in common pneumonia group, and the levels of CD4 + cells and 1, 25-dihydroxyvitamin D [1, 25-(OH) 2D] were lower than those in common pneumonia group (all P<0.05). After treatment, the levels of CRP, CD8 + cells and Beclin-1 in children with severe pneumonia were lower than those before treatment, and the levels of CD4 + cells and 1, 25-(OH) 2D were higher than those before treatment (all P<0.05). Multiple regression model analysis was established. The results showed that congenital heart disease, high CRP level, high CD8 + cells, high RSV load and high Beclin-1 level were risk factors for severe pneumonia in children with RSV infected pneumonia (all OR>1, P<0.05), and high CD4 + cells and 1, 25-(OH) 2D level were protective factors (all OR<1, P<0.05). Conclusions:Severe pneumonia in children with RSV infected pneumonia may be affected by congenital heart disease, CRP, CD4 + cells, CD8 + cells, 1, 25-(OH) 2D, RSV load and Beclin-1.

Objective To evaluate the effect of dexmedetomidine on Toll-like receptor 4 ( TLR4)/myeloid differentiation factor 88 ( MyD88)/nuclear factor Kappa B ( NF-κB) signaling pathway in the pe-ripheral blood mononuclear cells of elderly patients with diabetes mellitus undergoing lower extremity surger-y. Methods Forty elderly patients of both sexes with type 2 diabetes mellitus, aged 65-80 yr, with body mass index of 18. 5-27. 9 kg/m2 , of American Society of Anesthesiologists physical status Ⅱ or Ⅲ, with New York Heart Association Ⅰ or Ⅱ, undergoing lower extremity surgery with tourniquets under general anesthesia, were divided into 2 groups ( n=20 each) by using a random number table method: control group ( group C) and dexmedetomidine group ( group D) . Combined intravenous-inhalational anesthesia was applied. Dexmedetomidine was infused over 15 min in a dose of 1μg/kg after induction of anesthesia, fol-lowed by a continuous infusion of 0. 5 μg·kg-1 ·h-1 until the end of surgery in group D, while the equal volume of normal saline was given instead of dexmedetomidine in group C. Before using the the tourniquet and at 15 min, 1 h and 24 h after loosing the tourniquet, arterial blood samples were collected for determi-nation of the expression of TLR4, NF-κB and MyD88 in peripheral blood mononuclear cells and concentra-tions of tumor necrosis factor-alpha ( TNF-α) , interleukin-1β ( IL-1β) , cardiac troponin I ( cTnI ) and creatine kinase-MB ( CK-MB) in plasma. Results Compared with group C, the expression of TLR4, NF-κB and MyD88 in peripheral blood mononuclear cells was significantly down-regulated, and the concentra-tions of TNF-α, IL-1β, cTnI and CK-MB in plasma were decreased at each time point after loosing the tourniquet in group D ( P＜0. 05) . Conclusion The mechanism by which dexmedetomidine reduces myo-cardial damage may be related to inhibiting TLR4/MyD88/NF-κB signaling pathway and reducing systemic inflammatory responses in elderly patients with diabetes mellitus undergoing lower extremity surgery.

Objective To observe the efficacy of gray-scale ultrasound-based radiomics for differentiating peripheral pulmonary adenocarcinoma and squamous cell carcinoma.Methods Data of 88 patients with single peripheral lung adenocarcinoma and 58 patients with single peripheral lung squamous cell carcinoma proved pathologically with puncture biopsy and clearly visualized with lung ultrasound were retrospectively analyzed.The patients were divided into training set(n=103)and test set(n=43)at the ratio of 7:3.Based on gray-scale ultrasound of training set,radiomics features associated with differential diagnosis of peripheral lung adenocarcinoma and lung squamous cell carcinoma were extracted and screened.Using 4 different classifiers,including support vector machine(SVM),linear discriminant analysis(LDA),logistic regression(LR)and the least absolute shrinkage and selection operator combined with logistic regression(LASSO-LR),4 corresponding radiomics models were obtained,and the relative best models were selected according to their performances under 10-fold cross validation.The receiver operating characteristic curves were drawn,the areas under the curve(AUC)were calculated to evaluate the differentiating efficacy of each model,and DeLong test was used for the comparison.The differentiating accuracy of models were obtained under the best cutoff value with the maximum Youden index.Results The AUC of SVM,LDA,LR and LASSO-LR radiomics models for differentiating peripheral lung adenocarcinoma and lung squamous carcinoma in test set was 0.864,0.867,0.880 and 0.844,respectively,and no significant difference was found among 4 models(all P＞0.05).Under the best cutoff value of each model,the corresponding accuracy of SVM,LDA,LR and LASSO-LR radiomics models for differentiating peripheral lung adenocarcinoma and lung squamous cell carcinoma was 86.05％,83.72％,88.37％and 86.05％,respectively.Conclusion Radiomics models based on gray-scale ultrasound could be used to differentiate peripheral lung adenocarcinoma and lung squamous cell carcinoma.