Objective To investigate the clinical efficacy ofβ-lactam combined with macrolides antibiotics in treatment of severe community-acquired pneumonia (CAP) in children. Methods Children with severe CAP on admission between 2012 February and 2012 April were divided into treatment group and control group. With the same symptom specific supportive treat-ment, the patients in the treatment group were treated with both cefmetazole and azithromycin, while the patients in the control group were treated with cefmetazole alone. The total effective rate, number of days of symptoms and signs disappeared and num-ber of days of hospitalization were observed. Results The total effective rate was 87.8%in the trearment group and 61.3%in the control group with significant difference (P<0.05). Compared with control group, the recovery time of temperature, time of pulmonary rale disappearing and cough retraction were reduced (P<0.05). As well as the number of days of hospitalization was decreased (P<0.05). Conclusions The treatment of severe CAP in children with combination of azithromycin and cefmetazole results in better curative effect. A combined medication ofβ-lactam and macrolides antibiotics may be rational and effective.

Objective:To investigate the effects and possible mechanisms of caffeic acid phenethyl ester (CAPE) on the replication, amplification, and fibre formation of prions (PrP Sc). Methods:The CCK8 assay was used to detect the cell viability of the prion-infected cell model SMB-S15 after CAPE treatment for 3 days and 7 days and the maximum safe concentration of CAPE for SMB-S15 was obtained. The cells were treated with a concentration within a safe range, and the content of PrP Sc in the cells before and after CAPE treatment was analyzed by western blot. Protein misfolding cycle amplification (PMCA) and western blot were used to assess changes in PrP Sc level in amplification products following CAPE treatment. Real-time-quaking induced conversion assay (RT-QuIC) technology was employed to explore the changes in fibril formation before and after CAPE treatment. The binding affinity between CAPE and murine recombinant full-length prion protein was determined using a molecular interaction assay. Results:CCK8 cell viability assay results demonstrated that treatment with 1 μmol/L CAPE for 3 and 7 days did not exhibit statistically significant differences in cell viability compared to the control group (all P<0.05). However, when the concentration of CAPE exceeded 1 μmol/L, a significant reduction in cell viability was observed in cells treated with CAPE for 3 and 7 days, compared to the control group (all P<0.05). Thus, 1 μmol/L was determined as the maximum safe concentration of CAPE treatment for SMB-S15 cells. The western blot results revealed that treatment with CAPE for both 3 and 7 days led to a detectable reduction in the levels of PrP Sc in SMB-S15 cells (all P<0.05). The products of PMCA experiments were assessed using western blot. The findings revealed a significant decrease in the levels of PrP Sc (relative grey value) in the PMCA amplification products of adapted-strains SMB-S15, 139A, and ME7 following treatment with CAPE, as compared to the control group (all P<0.05). The RT-QuIC experimental results demonstrated a reduction in fibril formation (as indicated by ThT peak values) in CAPE-treated mouse-adapted strains 139A, ME7, and SMB-S15, as well as in SMB-S15 cells infected with prions. Furthermore, CAPE exhibited varying degrees of inhibition towards different seed fibrils formation, with statistically significant differences observed (all P<0.05). Notably, CAPE exhibited a more pronounced inhibitory effect on ME7 seed fibrils. Molecular interaction analyses demonstrated significant binding between CAPE and murine recombinant prion protein, and the association constant was (2.92±0.41)×10 -6 mol/L. Conclusions:CAPE inhibits PrP Sc replication, amplification, and fibril formation in vitro possibly due to specific interactions with the prion protein at the molecular level.

Objective:To investigate the effects and possible mechanisms of caffeic acid phenethyl ester (CAPE) on the replication, amplification, and fibre formation of prions (PrP Sc). Methods:The CCK8 assay was used to detect the cell viability of the prion-infected cell model SMB-S15 after CAPE treatment for 3 days and 7 days and the maximum safe concentration of CAPE for SMB-S15 was obtained. The cells were treated with a concentration within a safe range, and the content of PrP Sc in the cells before and after CAPE treatment was analyzed by western blot. Protein misfolding cycle amplification (PMCA) and western blot were used to assess changes in PrP Sc level in amplification products following CAPE treatment. Real-time-quaking induced conversion assay (RT-QuIC) technology was employed to explore the changes in fibril formation before and after CAPE treatment. The binding affinity between CAPE and murine recombinant full-length prion protein was determined using a molecular interaction assay. Results:CCK8 cell viability assay results demonstrated that treatment with 1 μmol/L CAPE for 3 and 7 days did not exhibit statistically significant differences in cell viability compared to the control group (all P<0.05). However, when the concentration of CAPE exceeded 1 μmol/L, a significant reduction in cell viability was observed in cells treated with CAPE for 3 and 7 days, compared to the control group (all P<0.05). Thus, 1 μmol/L was determined as the maximum safe concentration of CAPE treatment for SMB-S15 cells. The western blot results revealed that treatment with CAPE for both 3 and 7 days led to a detectable reduction in the levels of PrP Sc in SMB-S15 cells (all P<0.05). The products of PMCA experiments were assessed using western blot. The findings revealed a significant decrease in the levels of PrP Sc (relative grey value) in the PMCA amplification products of adapted-strains SMB-S15, 139A, and ME7 following treatment with CAPE, as compared to the control group (all P<0.05). The RT-QuIC experimental results demonstrated a reduction in fibril formation (as indicated by ThT peak values) in CAPE-treated mouse-adapted strains 139A, ME7, and SMB-S15, as well as in SMB-S15 cells infected with prions. Furthermore, CAPE exhibited varying degrees of inhibition towards different seed fibrils formation, with statistically significant differences observed (all P<0.05). Notably, CAPE exhibited a more pronounced inhibitory effect on ME7 seed fibrils. Molecular interaction analyses demonstrated significant binding between CAPE and murine recombinant prion protein, and the association constant was (2.92±0.41)×10 -6 mol/L. Conclusions:CAPE inhibits PrP Sc replication, amplification, and fibril formation in vitro possibly due to specific interactions with the prion protein at the molecular level.