OBJECTIVE:To study chemical compounds of Monoraphidium dybowskii,and to investigate the in vitro antibacte-rial and antioxidant activities of isolated compounds. METHODS:The ethanol extract of M. dybowskii were extracted with aether petrolei,ethyl acetate and n-butyl alcohol. The ethyl acetate extract was separated from M. dybowskii and chemical components were analyzed by sillica gel column chromatogram,HPLC and GC-MS. Their structures were identified according to physicochemi-cal properties and NMR. MIC of 4 isolated compounds to Pseudomonas aeruginosa,Candida albicans,Bacillus subtilis and Esche-richia coli were determined by resazurin disc test. Free radical scavenging rate(concluated by IC50)and reducing capacity were mea-sured by 1,1-diphenyl-2-picryl-diazanyl (DPPH) and ferric reducing antioxidant power (FRAP) assay. RESULTS:Compounds 1-6 were obtained from E4 and E5 segments of ethyl acetate extract of M. dybowskii,and their structures were identified as stigmas-terol,diisonoyladipate,indole-3-carboxylic acid,(+)-epiloliolide,(-)-loliolide,5-hydroxy-3,4-dimethy-5-pentyl-2(5H)-furanone. MIC of compounds 3-6 were 10-500 μg/mL,and IC50 ranged 22.02-71.01 μg/mL;FRAP ranged (62.04 ± 5.36)-(281.22 ± 8.3) μmol/L. CONCLUSIONS:M. dybowskii contains multiple lipid and alkanoic acid,and possesses certain in vitro antibacterial and antioxidant activities.

Objective:To evaluate the functional changes of lateral pterygoid muscle (LPM) in the patients with temporomandibular disorders (TMD) using histogram texture analysis.Methods:A total of 28 TMD patients, including 15 males and 13 females, aged (26.2±12.1) years (15-62 years), were enrolled in the outpatient clinic of Department of Radiology, Hainan Hospital of Chinese PLA General Hospital from May 2016 to April 2020. At the same time, 13 volunteers with normal temporomandibular joint [6 males and 7 females, aged (23.5±3.3) years (20-30) years] were recruited. All participants were performed with temporomandibular joint MRI scan, and the subjects were classified into 3 groups according to the disc displacement: TMD with disc without displacement (TMD-DwoD), TMD with disc displacement without reduction (TMD-DDwoR) and NC with disc displacement without reduction (NC-DwoD) for each temporomandibular joint. The area, signal intensity, coefficient of variation (CV) of mean signal intensity and histogram texture of the superior belly of LPM (SBLPM) and inferior belly of LPM (IBLPM) were measured using regions of interests.Results:The area of SILPM presented significantly smaller in TMD-DwoD [(67.36±30.23) mm 2] compared with that in NC-DwoD [(91.42±45.01) mm 2] ( P<0.05) and in TMD-DDwoR group [(72.27±37.53) mm 2] ( P>0.05). The mean signal intensity of SBLPM was identified significantly higher in TMD-DwoD (304.20±29.90) and TMD-DDwoR (315.06±40.20) compared with that in NC-DwoD (269.79±25.54) ( P<0.05). The CV of mean signal intensity of SBLPM presented significantly higher in TMD-DwoD (8.89±2.60) compared with that in NC-DwoD (6.76±1.82) and TMD-DDwoR (7.63±1.62) ( P<0.05). The skew and kurtosis showed no significantly differences among three groups for SBLPM ( P>0.05). The mean signal intensity and CV for IBLPM presented significantly higher in TMD-DwoD (286.69±23.48 and 9.96±2.24, respectively) and TMD-DDwoR (275.98±30.55 and 10.25±1.96, respectively) compared with that in NC-DwoD (243.56±17.04 and 8.49±1.94, respectively) ( P<0.05). The skewness showed significantly lower in TMD-DwoD (0.90±0.94) and TMD-DDwoR (0.73±0.97) compared with that in NC-DwoD (1.40±1.03) ( P<0.05). The area and kurtosis for IBLPM showed no significant differences among three groups ( P>0.05). Conclusions:The MR histogram texture analysis could primarily be considered as a tool to evaluate the LPM function in TMD patients.

Objective:To evaluate the histological changes of the retrodiscal tissue in the patients with temporomandibular disorders (TMD).Methods:Thirty-three TMD patients were performed with temporomandibular joint (TMJ) MRI examinations from April 2018 to April 2020 in TMD clinic, Hainan Hospital of General Hospital of Chinese PLA. The patients groups were classified according to the disc position as follows: normal position (NP) (29 TMJ), disk displacement with reduction (DDwR) (14 TMJ) and disk displacement without reduction (DDwoR) (23 TMJ). The gray-level co-occurrence matrix (GLCM) analysis was applied with the retrodiscal tissue on the open oblique sagittal proton weighted images. The texture parameters included as follows: angular second moment (ASM), contrast, correlation, inverse difference moment (IDM) and entropy. The statistical methods mainly included Kruskal-Wallis H test, one-way analysis of variance and receiver operating characteristic curve (ROC), to analyze the texture characteristic parameters of the retrodiscal tissue are statistically significant. Results:There was no significant difference of the retrodiscal tissue′s ASM, contrast, correlation and IDM among 3 groups ( P>0.05). The entropy in NP group (3.98±0.44) and DDwR group (4.20±0.52) presented significant higher than that in DDwoR group (3.70±0.38) ( P<0.05). ROC analysis for the entropy demonstrated that the area under the curve was 0.70 when differentiating NP and DDwR (cut-off value 0.38, sensitivity 82.61%, specificity 55.17%), and was 0.79 when differentiating DDwR and DDwoR (cut-off value 0.47, sensitivity 82.61%, specificity 64.29%). Conclusions:Texture entropy could be primarily used to evaluate the histological and pathological changes of the retrodiscal tissue in the TMD patients.