Objective To screen the anti-Streptococcus pneumoniae(Spn)active ingredients in vitro from different po-lar parts of Pilea peltata,and to examine the combined antibacterial effect of the active ingredient and amoxicillin(AMX).Methods A 96-well plate microdilution method was used to determine the minimum inhibitory concentration(MIC)of different polar parts;the most active polar part was separated by preparative high-performance liquid chromatography,and the active ingre-dients were identified using spectral technology.The fractional inhibitory concentration(FIC)of active ingredients and AMX was determined by the 96-well plate chessboard microdilution method.The crystal violet method was used to investigate the effect of ac-tive ingredients on Spn biofilm.The effect of active ingredients on the appearance and morphology of Spn was investigated under the electron microscope.Results The MICs of the petroleum ether part,chloroform part,ethyl acetate part,n-butanol part,and water part were 1.000,1.000,0.500,1.000,and 2.000 mg·mL-1 respectively,among which the ethyl acetate part had the stron-gest antibacterial activity.Three compounds were isolated from ethyl acetate,namely 5,7,3',4'-tetramethoxyflavone 1,8-O-(p-coumaroyl)-1(10)E,4(5)E-humuladien-8-ol 2 and 1-O-p-coumaroyl copaborneol 3.These compounds were all isolated for the first time from Pilea peltate,their MICs against Spn were 200.000,50.000,and 25.000 μg·mL-1 respectively,and the compound 3 had the strongest antibacterial activity;the FIC value of AMX and compound 3 was 0.50,which had a synergistic antibacterial effect on Spn.Both AMX and compound 3 had inhibitory effects on Spn biofilm,but the biofilm inhibition rate of compound 3(59.10±1.04％)was significantly lower than AMX(87.38±0.84)％(P＜0.01);Moreover,there was no significant difference in biofilm inhibition rate between the combination of the two and AMX(P＞0.05).The scanning electron microscope results showed that the bacterial cells in the compound 3 group had a smooth surface but varying degrees of depression.The surface of the bacteri-al cells in the AMX group and the AMX combined compound 3 group showed severe swelling and rupture.Conclusions Fla-vonoids and sesquiterpenoids are both the anti-Spn active components of Pilea peltate.Among them,sesquiterpenoids have more potent antibacterial activity,and their antibacterial action mechanism is related to inhibiting bacterial biofilms.Compound 3 and AMX have a synergistic antibacterial effect on Spn,but its mechanism of action is not by enhancing biofilm inhibition;although compound 3 cannot destroy the cell wall of Spn,it still has a negative impact on the appearance of the bacteria.

Objective To screen the anti-Streptococcus pneumoniae(Spn)active ingredients in vitro from different po-lar parts of Pilea peltata,and to examine the combined antibacterial effect of the active ingredient and amoxicillin(AMX).Methods A 96-well plate microdilution method was used to determine the minimum inhibitory concentration(MIC)of different polar parts;the most active polar part was separated by preparative high-performance liquid chromatography,and the active ingre-dients were identified using spectral technology.The fractional inhibitory concentration(FIC)of active ingredients and AMX was determined by the 96-well plate chessboard microdilution method.The crystal violet method was used to investigate the effect of ac-tive ingredients on Spn biofilm.The effect of active ingredients on the appearance and morphology of Spn was investigated under the electron microscope.Results The MICs of the petroleum ether part,chloroform part,ethyl acetate part,n-butanol part,and water part were 1.000,1.000,0.500,1.000,and 2.000 mg·mL-1 respectively,among which the ethyl acetate part had the stron-gest antibacterial activity.Three compounds were isolated from ethyl acetate,namely 5,7,3',4'-tetramethoxyflavone 1,8-O-(p-coumaroyl)-1(10)E,4(5)E-humuladien-8-ol 2 and 1-O-p-coumaroyl copaborneol 3.These compounds were all isolated for the first time from Pilea peltate,their MICs against Spn were 200.000,50.000,and 25.000 μg·mL-1 respectively,and the compound 3 had the strongest antibacterial activity;the FIC value of AMX and compound 3 was 0.50,which had a synergistic antibacterial effect on Spn.Both AMX and compound 3 had inhibitory effects on Spn biofilm,but the biofilm inhibition rate of compound 3(59.10±1.04％)was significantly lower than AMX(87.38±0.84)％(P＜0.01);Moreover,there was no significant difference in biofilm inhibition rate between the combination of the two and AMX(P＞0.05).The scanning electron microscope results showed that the bacterial cells in the compound 3 group had a smooth surface but varying degrees of depression.The surface of the bacteri-al cells in the AMX group and the AMX combined compound 3 group showed severe swelling and rupture.Conclusions Fla-vonoids and sesquiterpenoids are both the anti-Spn active components of Pilea peltate.Among them,sesquiterpenoids have more potent antibacterial activity,and their antibacterial action mechanism is related to inhibiting bacterial biofilms.Compound 3 and AMX have a synergistic antibacterial effect on Spn,but its mechanism of action is not by enhancing biofilm inhibition;although compound 3 cannot destroy the cell wall of Spn,it still has a negative impact on the appearance of the bacteria.

Objective:To explore the microbiological and disease distribution characteristics of multidrug-resistant bacteria in patients hospitalized in a critical care rehabilitation ward, and to analyze the risk factors leading to multidrug-resistant bacterial infections.Methods:Microbiology screening data describing 679 patients admitted to a critical care rehabilitation ward were retrospectively analyzed to divide the subjects into a multidrug-resistant group (positive for multidrug-resistant bacterial infections, n=166) and a non-multidrug-resistant group (negative for multidrug-resistant bacterial infections, n=513). The risk factors were then analyzed using logistic regression. Results:Among 369 strains of multidrug-resistant bacteria observed, 329 were gram-negative bacteria (89.2%), mainly Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli. They were distributed in sputum (56.9%) and mid-epidemic urine (28.2%) specimens. Patients whose primary disease was hemorrhagic or ischemic cerebrovascular disease accounted for 40.96% and 23.49% of the multidrug-resistant bacterial infections, respectively. Logistic regression analysis showed that albumin level, dependence on mechanical ventilation, central venous cannulation, or an indwelling urinary catheter or cystostomy tube were significant independent predictors of such infections.Conclusion:The multidrug-resistant bacterial infections of patients admitted to the critically ill rehabilitation unit are mainly caused by gram-negative bacteria. Their occurrence is closely related to low albumin levels and mechanical ventilation, as well as to bearing an indwelling central venous catheter, a urinary catheter or a cystostomy catheter.

ObjectiveTo establish an ischemia-reperfusion model in cynomolgus macaques and to analyse the effects of edaravone intervention. MethodsA total of fifteen adult male cynomolgus macaques were randomly divided into three groups: sham operation (Sham group, n=3), ischemia-reperfusion model (Model group, n=6) and edaravone treatment (Edaravone group, n=6). Ischemic-reperfusion model of cynomolgus macaques was established by clamping the M1 branch of the left cerebral artery for 1 h. After 2 h of reperfusion, the animals in Edaravone group were injected with 0.5 mg/kg edaravone intravenously for intervention treatment, while the animals in Sham and Model groups were injected with an equal volume of normal saline intravenously, twice a day, from the 2nd to 7th day. The behavioral video recordings, clinical observations and neurological deficit scores of cynomolgus macaques were obtained, and brain edema volume and cerebral ischemia volume were statistically analyzed. ResultsCompared with the Sham group, the animals in Model group showed typical symptoms of ischemic stroke, with a significant increase in the neurological deficit score， the volumes of edema and infarct of brain tissue (all P＜0.01). Compared with Model group, the neurological deficit score, the volumes of edema and infarct of brain tissue were significantly reduced in Edaravone group (all P＜0.05). ConclusionAn animal model of ischemia-reperfusion in cynomolgus macaques was successfully established, and edaravone was confirmed to alleviate the damage caused by ischemia-reperfusion.

Objective:To investigate the efficacy and safety of cedilanid in the treatment of severe pneumonia in infants and the value of preventing heart failure.Methods:A total of 80 children with severe pneumonia admitted to Dezhou Maternal and Child Health Hospital from January 2019 to December 2020 were selected and randomly divided into the control group and the observation group, with 40 cases in each group. The control group received comprehensive treatment, while the observation group was treated with cedilanid (0.01 mg/kg, one-time intravenous injection) on the basis of the control group. The efficacy of both groups was observed after 5 d of treatment. The incidence of heart failure, correction time of heart failure, improvement time of symptoms and signs, and length of hospitalization time were compared between the two groups; the inflammatory markers, myocardial markers and arterial blood gas indexes were compared between the two groups before and after the treatment.Results:The total effective rate in the observation group was higher than that in the control group, and the incidence of heart failure in the observation group was lower than that in the control group: 90.0% (36/40) vs. 72.5% (29/40), 32.5%(13/40) vs. 10.0%(4/40), the differences were statistically significant ( χ2 = 4.02, 4.10, P<0.05). The improvement time of symptoms and signs (restlessness elimination, respiratory improvement, heart rate improvement and disappearance of rhonchus in lung) in the observation group were less than those in the control group ( P<0.05). The levels of procalcitonin (PCT) and N-terminal pro-brain natriuretic peptide (NT-ProBNP), myocardial troponin I(cTnI), and creatine kinase isoenzyme (CK-MB) in the observation group after treatment were lower than those in the control group: (6.15 ± 1.03) μg/L vs. (10.85 ± 2.12) μg/L, (112.02 ± 30.09) ng/L vs. (215.39 ± 55.08) ng/L, (0.68 ± 0.17) μg/L vs. (1.12 ± 0.34) μg/L, (19.05 ± 6.11) U/L vs. (28.97 ± 7.82) U/L, P<0.05. The levels of oxygen partial pressure (PaO 2), blood oxygen saturation (SaO 2) and oxygenation index (PaO 2/FiO 2) in the observation group after treatment were higher than those in the control group: (6.15 ± 1.03) μg/L vs. (10.85 ± 2.12) μg/L, (112.02 ± 30.09) ng/L vs. (215.39 ± 55.08) ng/L, (0.68 ± 0.17) μg/L vs. (1.12 ± 0.34) μg/L, (19.05 ± 6.11) U/L vs. (28.97 ± 7.82) U/L, P<0.05. Conclusions:Early application of small dose of cedilanid in infants with severe pneumonia can effectively reduce the occurrence of heart failure, improve the clinical symptoms and blood gas indicators, with significant curative effect, which is worthy of promotion.