The plants of the genus Ehretia Linn. composed of about 50 species mainly distributed in tropical Asia and Africa.They have been used as folk medicines or traditional tea to treat various ailments in China for a long time. This contribution reviews the chemical constituents isolated from the plants of the genus Ehretia Linn. and related biological activities of these species in the past few decades. The compounds in the genus mainly belong to the classes of phenolic acids, flavonoids, benzoquinones, cyanogenetic glycosides, and fatty acids. The main biological activities include antioxidant, anti-inflammatory, antisnake venom, and anti-allergic activities.

Objective To observe the therapeutic effects of urolithin A(UA)on respiratory syncytial virus(RSV)-induced lung infection in neonatal mice and explore the underlying mechanisms.Methods Babl/c mice(5-7 days old)were subjected to nasal instillation of RSV and received intraperitoneal injection of saline or 2.5,5 and 10 mg/kg UA 2 h after the infection and then once daily for 2 weeks.Bronchoalveolar lavage fluid(BALF)was then collected for detection of inflammatory cells and mediators,and lung pathology was evaluated with HE staining.RSV-infected BEAS-2B cells were treated with 2.5,5 or 10 μmol/L UA.Inflammatory factors,cell viability,apoptosis and autophagy were analyzed using ELISA,CCK-8 assay,TUNEL staining,flow cytometry,Western blotting and immunofluorescence staining.The cellular expressions of miR-136 and Sirt1 mRNAs were detected using qRT-PCR.A dual-luciferase reporter system was used to verify the binding between miR-136 and Sirt1.Results In neonatal Babl/c mice,RSV infection caused obvious lung pathologies,promoted pulmonary cell apoptosis and LC3-Ⅱ/Ⅰ,Beclin-1 and miR-136 expressions,and increased the total cell number,inflammatory cells and factors in the BALF and decreased p62 and Sirt1 expressions.All these changes were alleviated dose-dependently by UA.In BEAS-2B cells,RSV infection significantly increased cell apoptosis,LC3B-positive cells and miR-136 expression and reduced Sirt1 expression(P<0.01),which were dose-dependently attenuated by UA.Dual-luciferase reporter assay confirmed the binding between miR-136 and Sirt1.In RSV-infected BEAS-2B cells with UA treatment,overexpression of miR-136 and Ex527 treatment both significantly increased the inflammatory factors and cell apoptosis but decreased LC3B expression,and these changes were further enhanced by their combined treatment.Conclusion UA ameliorates RSV-induced lung infection in neonatal mice by activating miR-136-mediated Sirt1 signaling pathway.

Objective To observe the therapeutic effects of urolithin A(UA)on respiratory syncytial virus(RSV)-induced lung infection in neonatal mice and explore the underlying mechanisms.Methods Babl/c mice(5-7 days old)were subjected to nasal instillation of RSV and received intraperitoneal injection of saline or 2.5,5 and 10 mg/kg UA 2 h after the infection and then once daily for 2 weeks.Bronchoalveolar lavage fluid(BALF)was then collected for detection of inflammatory cells and mediators,and lung pathology was evaluated with HE staining.RSV-infected BEAS-2B cells were treated with 2.5,5 or 10 μmol/L UA.Inflammatory factors,cell viability,apoptosis and autophagy were analyzed using ELISA,CCK-8 assay,TUNEL staining,flow cytometry,Western blotting and immunofluorescence staining.The cellular expressions of miR-136 and Sirt1 mRNAs were detected using qRT-PCR.A dual-luciferase reporter system was used to verify the binding between miR-136 and Sirt1.Results In neonatal Babl/c mice,RSV infection caused obvious lung pathologies,promoted pulmonary cell apoptosis and LC3-Ⅱ/Ⅰ,Beclin-1 and miR-136 expressions,and increased the total cell number,inflammatory cells and factors in the BALF and decreased p62 and Sirt1 expressions.All these changes were alleviated dose-dependently by UA.In BEAS-2B cells,RSV infection significantly increased cell apoptosis,LC3B-positive cells and miR-136 expression and reduced Sirt1 expression(P<0.01),which were dose-dependently attenuated by UA.Dual-luciferase reporter assay confirmed the binding between miR-136 and Sirt1.In RSV-infected BEAS-2B cells with UA treatment,overexpression of miR-136 and Ex527 treatment both significantly increased the inflammatory factors and cell apoptosis but decreased LC3B expression,and these changes were further enhanced by their combined treatment.Conclusion UA ameliorates RSV-induced lung infection in neonatal mice by activating miR-136-mediated Sirt1 signaling pathway.

Objective To investigate the relationship between signal-to-noise ratio loss and electrocochleo-gram in noise exposed subjects and its assistive diagnosis value for hidden hearing loss.Methods Forty-one workers with a history of noise exposure were tested with pure tone audiometry,acoustic immittance,speech recognition un-der noise and electrocochleogram.They were divided into two groups according to their speech recognition ability under noise:Group A:SNR loss＜0(19 ears),Group B:SNR loss＞0(22 ears).The difference of electrocochleo-gram between the two groups was recorded and analyzed.Results The results of speech recognition test showed that there was significant difference in SNR loss between Group A and Group B(P＜0.05).The results of cochlear electrogram showed that the AP amplitudes of the two groups were significantly different at 96,90 and 80 dB nHL(P＜0.05).At 96,90,80,70,60 dB nHL,there were significant differences in SP amplitudes between the two groups(P＜0.001).At 96,90,80 and 70 dB nHL,there was significant difference in SP/AP amplitude ratio be-tween the two groups(P＜0.05).Conclusion There is a significant difference of SP/AP amplitude ratio between subjects with SNR loss of＜0 and＞0 at different sound intensities.