Objective:To establish an animal model of pneumonia for research on clinical prevention and treatment of bacterial pneumonia by infecting immunocompromised rats with drug-resistant Acinetobacter baumannii ( Ab) strains. Methods:Drug-resistant Ab strains were selected. Forty-eight SD rats were randomly divided into four groups: normal group, cyclophosphamide control group (intraperitoneal injection of 45 mg/kg cyclophosphamide), bacterial infection group (intratracheal instillation of 1.5×10 8 CFU Ab suspension), and bacterial infection+ immunosuppression group (intraperitoneal injection of 45 mg/kg cyclophosphamide+ intratracheal instillation of 1.5×10 8 CFU Ab suspension). Flow cytometry analysis was used to detect the proportion of CD4 + , CD8 + and NK cells in rat peripheral blood before as well as 3 d and 7 d after infection. A lung function meter was used to detect peak inspiratory flow (PIF), peak expiratory flow (PEF), tidal volume (Vt ) and forced expiratory volume in the second second/forced vital capacity (FEV 200/FVC) at 3 d and 7 d after modeling. ELISA was used to detect the levels of IL-6, TNF-α and IL-10 in the alveolar lavage fluid. HE staining was used to observe the morphology of rat lung tissues in each group. Bacterial loads in rat lung tissues were counted by bacterial culturing. Results:A decrease in voluntary activity was observed in rats in the cyclophosphamide control group, bacterial infection group and bacterial infection+ immunosuppression group after modeling. Lung rales could be heard in the bacterial infection group and bacterial infection+ immunosuppression group. Compared with the normal group, the cyclophosphamide control group showed decreased proportion of CD4 + and CD11b + NK cells and increased CD8 + cells in peripheral blood; the bacterial infection group showed decreased PIF, PEF, Vt and FEV 200/FVC, increased IL-6 and TNF-α levels and decreased IL-10 level in the alveolar lavage fluid, and higher bacterial load in lung tissues with mild widening of alveolar walls and inflammatory cell infiltration ( P<0.05, P<0.01). Compared with the cyclophosphamide control group and the bacterial infection group, the bacterial infection+ immunosuppression group showed a lower proportion of CD4 + cells and a higher proportion of CD8 + cells in rat peripheral blood, decreased PIF, PEF, Vt and FEV 200/FVC, increased IL-6 and TNF-α levels and decreased IL-10 level in alveolar lavage fluid, higher bacterial load in lung tissues, and aggravated widening of alveolar walls and inflammatory cell infiltration ( P<0.05, P<0.01). The proportion of CD11b + NK cells in peripheral blood of rats in the bacterial infection+ immunosuppression group was significantly lower than that in the bacterial infection group ( P<0.05, P<0.01). Conclusions:A bacterial pneumonia model was successfully constructed by infecting rats with Ab alone or in combination with cyclophosphamide immunosuppression. In the model constructed with Ab and cyclophosphamide immunosuppression, the rats had more severe pneumonia, which might be related to the reduced cellular immune function and the aggravated bacterial infection in rat lung tissues by cyclophosphamide.

Objective To investigate the relationship between the CD 8 +T cells results of clinical automatic analysis platform and the CD8lowT and CD8highT cell subsets.Methods A total of 1316 cases of lymphocyte and flow cytometry data were collected from the First Affiliated Hospital of China Medical University from December 2015 to September 2016 by cross-sectional study. There were 287 cases of malignant tumor , 389 cases of autoimmune disease , 320 healthy people and 320 cases of HIV infection , then to get automatic analysis platform returns result of CD 8+T cell.FlowJo software was used to analyze the CD8low T and CD8high T lymphocyte subsets in the patients , and the results were compared with the results of CD8 +T cells returned by the clinical automatic analysis platform .Results The results of clinical returns CD8 +T cells were consistent with the results of CD 8high T cells in patients with different diseases , and were not exactly the same as the results of CD8lowT cells, and the difference was as follows:the results of CD8low T cells in HIV-infected patients were significantly lower than those of healthy people (56.2 ±42.0, 68.8 ± 45.9, cells/μl P<0.001), which were different from the clinical results of CD 8 +T cells.The results of clinical report of CD8 +T cells were statistically correlated with CD8high T cells and CD8low T cells, and the correlation between CD8 +T cells and CD8highT were higher than that of CD8lowT cells.There was a positive correlation between CD8low T cell count and CD4 +T cell count ( r=0.204, P<0.001) .CD8low T was significantly higher in patients on antiviral treatment than that in untreated group (58.3 ±43.9, 42.9 ± 26.5, cells/μl, P<0.001).After treatment for more than 2 years, the CD8lowT cells in patients with CD4<500 cells/μl were significantly lower than those in patients with CD 4>500 cells/μl (50.1 ±47.0, 66.3 ±46.6, cells/μl, P<0.001).Conclusions The clinical report of CD8 +T cells was consistent with the results of CD8highT cells, and there was a great difference between the results of CD 8lowT cells and the results of CD8 +T cells.CD8low T cells were significantly reduced in HIV infected patients , and CD8low T cells could be effectively reconstructed by antiviral therapy .

Objective:To explore the surgical strategy of coronary artery bypass grafting(CABG) for moderate ischemic mitral regurgitation(IMR), and to clarify the impact of mitral valve surgical intervention(MVS) on the long-term prognosis of such patients.Methods:The clinical data of 234 consecutive patients with moderate IMR who received CABG from January 2013 to December 2018 were retrospectively included, with 184 males and 50 females. The age ranged from 29 to 78 years, with a mean of(61.5 ± 8.7) years old. According to whether MVS was performed at the same time, they were divided into CABG group(108 cases, CABG alone) and CABG+ MVS group(126 cases, CABG+ MVS at the same time). The long-term cardiac events, all-cause deaths, major cardiovascular and cerebrovascular adverse events(MACCE) and other end events were followed up. A matching queue was established by propensity matching score for statistical analysis.Results:After propensity matching score, a matching queue was established, including 78 pairs of patients. Survival analysis showed that the incidence of long-term cardiac events and postoperative new onset atrial fibrillation in CABG+ MVS group was significantly higher( P<0.05). However, there was no significant difference between the two groups in all-cause mortality, cardiogenic mortality, and the incidence of MACCE events( P>0.05). Cox regression analysis showed that simultaneous CABG+ MVS was a risk factor for long-term cardiac events and new postoperative atrial fibrillation. The results of subgroup studies showed that for patients without tricuspid regurgitation before operation, left ventricular end diastolic diameter>55 mm, and left ventricular ejection fraction(LVEF) ≤0.55, the probability of cardiac events after MVS at the same time of CABG was higher( P<0.05). However, patients with no tricuspid regurgitation before operation, left ventricular end diastolic diameter>55 mm, LVEF≤0.55, and left atrial diameter≥40 mm had a higher probability of atrial fibrillation after MVS at the same time of CABG( P<0.05). Conclusion:CABG can improve left ventricular remodeling in patients with moderate IMR, whether MVS intervention is performed at the same time or not, and the long-term survival rate of both is similar. CABG+ MVS in the same period can maintain a low residual reflux, but the incidence of long-term cardiac events and arrhythmias is high. The longer-term prognosis needs to be further studied. The surgical strategy of such patients should be selected individually according to the specific situation and the surgical quality in medical centers.

Objective A model for studying oral ulcers induced by betel nut-extract was constructed in rats.Changes in the structure and diversity of oral flora were observed to explore the involvement of oral flora and local inflammatory factors in the pathogenesis of oral ulcers induced by betel nut-extract and to provide theoretical support for the prevention and treatment of oral ulcers in the clinic.Methods Thirty SD rats were randomly divided into normal,model and intervention groups(Guilin watermelon cream,8 mg/d for 7 days),with 10 rats/group.The oral mucosa of rats was subcutaneously injected with 10 g/mL of betel nut-extract to generate an oral ulcer model.The histomorphological changes were observed,and ulcer area and ulcer scores were assessed.Local oral tissue tumor necrosis factor-α(TNF-α),interleukin(IL)-2 and IL-8 levels were determined.Oral mucosal tissues were sampled for HE staining and analyzed for the structural distribution of oral flora and the diversity of microbial communities using high-throughput sequencing method.Results Compared with rats in the normal group,those in the model group had an increased ulcer area,significantly increased ulcer scores(P＜0.01),and significantly increased levels of TNF-α,IL-2 and IL-8 in the oral mucosal tissues(P＜0.01).The amount Streptococcus(P＜0.05)and Veillonella(P＜0.001)in the oral saliva of the model group rats was significantly reduced.The model group rats showed oral mucosal epithelial cell hyperplasia or focal necrosis,mucosal lamina propria edema,and hemorrhage accompanied by mass neutrophil and monocyte infiltration.Compared with the model group rats,the intervention group rats had significantly reduced ulcerated area(P＜0.05,P＜0.01)and ulcer scores(P＜0.05).And oral mucosal tissue levels of TNF-α(P＜0.01),IL-2(P＜0.05)and IL-8(P＜0.05),as well as significantly increased Streptococcus(P＜0.001)and Veillonella(P＜0.01)and significantly reduced Staphylococcus(P＜0.01)in the oral saliva.The degree of lesions in the oral mucosal tissues was significantly improved in the intervention group.Conclusions Betel nut-extract can be used to successfully reproduce a rat model of oral ulcer,and it is speculated that the development of oral ulcers after exposure to betel nut-extract may be related to an imbalance in the oral flora and local tissue inflammatory mediators.