Objective: To investigate the association between edentulism and the risk of social isolation in middle-aged and elderly populations, provide empirical evidence for formulating social isolation prevention and intervention policies targeting edentulous middle-aged and elderly populations. Methods: Data were derived from the baseline survey (2011) and three follow-ups (2013, 2015, 2018) of the China Health and Retirement Longitudinal Study (CHARLS). Participants were enrolled in the follow-up from the baseline. Those identified as socially isolated in any of the follow-up surveys conducted in 2013, 2015, or 2018 were considered to have reached the endpoint; otherwise, the follow-up was continued until the end of the 2018 survey; 9 870 individuals were ultimately included. Subjects were grouped by edentulism status. Chi-square test and multivariate Cox regression analysis were performed using Stata 17.0. Results: During a median follow-up of 6.54 years, 1 800 cases of social isolation occurred, with an incidence rate of 18.23%（17.47%~18.99%）. Multivariate Cox regression showed that edentulism was associated with an increased risk of social isolation (HR=1.21, 95% CI: 1.03-1.42) after adjusting for confounders. Subgroup analysis revealed population heterogeneity. Sensitivity analyses confirmed the stability of the results. Conclusion Edentulism is associated with an increased risk of social isolation in middle-aged and elderly adults.

Objective To observe the effects of traditional Chinese medicine aqueous extract on acne vulgaris models of rabbit's ear.We observed the medical effects of traditional Chinese medicine aqueous on rabbit's ear acne vulgaris models.Methods 7 twelve-week's old male rabbits were selected to establish acne vulgaris models by Kligman method.Coal tar was daubed at the opening of rabbits' ears tubes about 2 cm × 2 cm areas by the frequency of once a day for two weeks.Then 50 μl bacterial suspension of the propionibacterium acnes was subcutaneously injected into each ear of rabbit at the seventh day which concentration of propionibacterium acnes was 1.0)× 108 CFU/ml.14 ears of rabbits were divided into 7 groups randomly after the molds were finished,two ears per group.6 group ears of rabbits were daubed with TCM aqueous extract respectively,while the last group was daubed with physiological saline on one ear and fusidic acid cream on the other one,once a day.At last,the treatment effects and adverse reactions were observed respectively on the 7th day,15th day and 21st day.Results The sWollen rabbits' ears were reclined and even disappeared in groups with six kinds of TCM aqueous extract after 7 days;the local hair follicles corneous plugs became flattened,pimples and comedos reduced in groups with aqueous extract of Cortex phellodendri,Scutellaria baicalensis and Rhubarb.Conclusions Aqueous extracts of Cortex phellodendri,Scutellaria baicalensis,Rhubarb,Sophora flavescens,Honeysuckle and Forsythia have therapeutical effects on rabbifs ear acne vulgaris models.

This study was aimed to identify the photodegradation impurities (PD1 and PD2) in melphalan hydrochloride and establish a method for determining PD1 and PD2.The structures of the photodegradation impurities were inferred by LC-MS/MS.The impurities were confirmed by comparing with synthesized impurities.An HILIC method was established to determine PD1 and PD2.The method was carried out on an Atlantis HILIC column(4.6 mm × 150 mm,3 μm) with the mobile phase consisting of 0.1 mol/L ammonium formate (adjusted to pH 3.0 with formic acid) and acetonitrile (13∶ 87) at the flow rate of 1.0 mL/min.The column temperature was 35 ℃.The detection wavelength was 260 nm.PD1 and PD2 were characterized as 4-amino-L-phenylalanine hydrochloride and 4-(2-chloroethyl) amino-L-phenylalanine hydrochloride,respectively.Melphalan hydrochloride,PD1 and PD2 were separated completely under the HILIC condition.The established HILIC method can be used to determine the photodegradation impurities.

In the HPLC analysis of bendamustine hydrochloride, two related substances(IMP01 and IMP02)were detected. These two related substances were identified by LC-MS/MS and their structural confirmation was unambiguously carried out by synthesis followed by characterization using Q-TOF/MS and NMR. Based on the spectral data, related substances IMP01 and IMP02 were characterized as 4-(1-methyl-5-morpholino-1H-benzo［d］imidazol-2-yl)butyric acid hydrochloride and 4-{1-methyl-5-［(2-chloroethyl)(2-hydroxyethyl)amino］-1H-benzo［d］imidazol-2-yl)} butyric acid hydrochloride, respectively. Bendamustine hydrochloride and its related substances were separated under the established LC-MS condition. HPLC is a useful method for the determination of the related substances in bendamustine hydrochloride. Results obtained are valuable for its manufacturing process and quality control.

BACKGROUND: In many studies, rats were commonly used as models of retrorsine-induced hepatic injury. Some reports have confirmed that retrorsine cannot inhibit proliferation of mouse hepatic cells. Other reports have shown that retrorsine has inhibitory effects on proliferation of mouse hepatic cells. OBJECTIVE: To study the liver regeneration after hepatic injury by creating mouse models treated with partial hepatectomy combination with retrorsine. METHODS: A total of 40 C57BL/6J mice were equally and randomly assigned to 2 groups. In the partial hepatectomy combined with retrorsine group, intraperitoneal injection of retrorsine 70 mg/kg was conducted, twice, within an interval of 2 weeks. Four weeks later, 2/3 hepatectomy was performed. In the partial hepatectomy group, intraperitoneal injection of saline 70 mg/kg was performed, twice, with an interval of 2 weeks. Four weeks later, 2/3 hepatectomy was performed. At 14 days after partial hepatectomy, the restoration of the livers was observed. The liver cell injury was observed at 3, 7 days with hematoxylin-eosin staining. The hepatocyte proliferation was observed at 3 days with BrdU staining. Oval cell proliferation was observed at 3, 7and 14 days with CK19 and C-kit antibody immunohistochemistry.RESULTS AND CONCLUSION: In the partial hepatectomy group, the damaged liver nearly restored to normal at 14 days after partial hepatectomy, and the result was contrary to partial hepatectomy combined with retrorsine group. Hematoxylin-eosin staining demonstrated that significant degeneration changes in hepatic cells in the partial hepatectomy combined with retrorsine group. BrdU staining showed that hepatocyte proliferation at day 3 was significantly determined in the partial hepatectomy group, but few in the partial hepatectomy combined with retrorsine group. CK19 and C-kit immunohistochemistry demonstrated that visible oval cell proliferation was seen in mice of partial hepatectomy combined with retrorsine group. First of all, hepatic oval cells appeared in portal area and differentiated into hepatic cells and bile duct cells, and then grew into the hepatic lobule gradually. These indicated that retrorsine can obviously inhibit hepatocyte regeneration after liver injury in mice. The model of mice treated with retrorsine and partial hepatectomy could induce oval cell proliferation.