OBJECTIVETo establish a HPLC-DAD method for determining concentrations of betulic acid and phenol red in intestinal circulation liquid, and probe into the absorption kinetic characteristics of betulic acid at different intestine segments in rats and the effect of different drug concentrations on absorption.

METHODThe rat intestinal absorption model was established to detect the impact of absorption site, drug concentration and pH value on drug absorption.

RESULTWithin the range from 75-125 mg x L(-1), the absorption rate and the quality concentration of betulic acid had a linear relation, with Ka value keeping unchanged. The absorption rate for each intestinal segment showed no remarkable difference, with Ka values in duodenum, jejunum, ileum and colon being (0.151 +/- 0.0049), (0.159 +/- 0.0056), (0.156 +/- 6.0083), (0.149 +/- 0.0041) h(-1), respectively.

CONCLUSIONBetulic acid is proved to be well absorbed in intestines marked by no specific absorption site in the intestine. The absorption mechanism of the drug conforms to passive transport mechanism and first-order kinetics. The bioavailability of betulic acid preparation can be increased by enhancing the dissolution rate and the solubility.

Animals ; Anti-HIV Agents ; pharmacokinetics ; Antineoplastic Agents, Phytogenic ; pharmacokinetics ; Chromatography, High Pressure Liquid ; Intestinal Absorption ; Intestines ; metabolism ; Kinetics ; Male ; Rats ; Rats, Sprague-Dawley ; Reference Standards ; Reproducibility of Results ; Sensitivity and Specificity ; Triterpenes ; pharmacokinetics

Objective To investigate the awareness of occupational health knowledge and concept of front-line workers in the automobile manufacturing industry. Methods A total of 1 188 front-line workers from 47 automobile manufacturing enterprises in Guangdong Province were selected as the research subjects using the judgment sampling method. The awareness of occupational health knowledge and concept of the workers was investigated using the Personal Questionnaire for National Survey of Occupational Health Literacy for Key Populations. Results The median (25th and 75th percentiles) awareness of occupational health knowledge and concept among the research subjects was 56.00% (44.00%, 64.00%). The awareness was higher among male workers than female workers (P<0.05). The awareness was higher among married workers than workers with other marital status (P<0.05). The awareness of workers with an education level of middle school or below was lower than those in the senior high school and junior college group and bachelor's degree or above group (all P<0.05). The awareness of workers in the group with personal monthly income <5 000 was lower than that in the other two income groups with personal monthly income ≥5 000 (all P<0.05). The awareness of workers in medium and large enterprises was higher than that of workers in small and micro enterprises (all P<0.05). The awareness of workers in foreign-funded enterprises was higher than that in private enterprises and other enterprises (all P<0.05). The awareness of workers with job tenure >5-10 and >10 years was higher than that in workers with job tenure of 1-≤5 years (P<0.05). The awareness for the 25 items of occupational health knowledge and concept among the research subjects ranged from 6.14% to 96.72%, with an average awareness of 54.46% for the 25 items. Conclusion The awareness of occupational health knowledge and concept of front-line workers in automobile manufacturing industry is not high in general, and it is influenced by gender, marriage status, education level, personal monthly income, enterprise nature and scale, and job tenure.

Objective:To observe the effect of edaravone dexborneol on anxiety and depression after stroke in rats, and to explore its possible mechanism.Methods:Totally 120 healthy adult male SD rats were randomly divided into sham operation group (sham), ischemia-reperfusion group (MCAO), edaravone group (Eda) and edaravone dexborneol group (ED) with 30 in each group.The middle cerebral artery occlusion (MCAO) model was established by thread occlusion.Rats in ED group and Eda group were intraperitoneally injected with edaravone(8 mg·kg -1·d -1) and edaravone dexborneol(edaravone: 8 mg·kg -1·d -1, dexborneol: 2 mg·kg -1·d -1) respectively.And rats in the other two groups were intraperitoneally injected with the same volume of normal saline.Some rats were killed after continuous administration for 3 days to detect molecular indexes, and the remaining rats were tested for behavior after continuous administration for 14 days.The levels of neclear factor κB(NF-κB)、phosphorylated NF-κB(p-NF-κB)、tumor necrosis α(TNF-α)、interleukin 1β(IL-1β) were detected by Western blot.The mRNA levels of TNF-α, IL-1β, cluster of differentiation 86(CD86), cluster of differentiation 206(CD206), inducible nitric oxide synthase(iNOS) were detected by RT-qPCR.M1 type microglia labeled with CD68, microglia labeled with ionized calcium binding adaptor molecule 1(Iba1) and neurons labeled with microtubule-associated protein 2(MAP2) were detected by immunofluorescence staining.The cerebral infarction volume was measured by TTC staining.Depression and anxiety behavior after stroke in rats was observed by the open field test and elevated plus maze test.SPSS 17.0 software was used for statistical analysis of the data.One-way ANOVA was used for multiple group comparison, and LSD-t test was used for pairwise comparison. Results:(1) The behavioral results showed that 14 days after ischemia-reperfusion, the number of entering into the open arm, the time spent in the open arm, and the time spent in the central area of the open field in the MCAO group were lower than those in the sham group ( t=20.77, 6.02, 14.63, all P<0.05). The number of entering into the open arm, the time spent in the open arm, and the time spent in the central area of the field in the ED group ( (16.22±0.49) times, (69.11±17.08) s, (3.80±0.37) s) were higher than those in the MCAO group ( (8.14±0.60) times, (41.18±9.81) s, (0.33±0.39) s) ( t=4.69, 0.38, 2.27, all P<0.05) and Eda group ( (11.11±0.26) times, (45.26±17.16) s, (1.14±0.19) s) ( t=8.63, 2.50, 7.86, all P<0.05). (2) Western blot results showed that 3 days after ischemia-reperfusion, p-NF-κB/NF-κB, TNF-α, and IL-1β levels in the MCAO group were higher than those in the sham group ( t=15.35, 12.35, 7.23, all P<0.05). The levels of p-NF-κB/NF-κB (0.49±0.02), TNF-α (0.73±0.03), IL-1β (0.61±0.01) of ischemic penumbra cortex in ED group were significantly lower than those of the MCAO group ( (1.14±0.05), (1.13±0.07), (1.34±0.14)) ( t=14.58, 7.86, 5.65, all P<0.05) and Eda group ( (0.93±0.03), (0.89±0.02), (1.04±0.36) ) ( t=9.82, 3.07, 3.30, all P<0.05). (3) RT-qPCR results showed that the level of TNF-α mRNA (1.98±0.18), IL-1β mRNA (2.00±0.35), CD86 mRNA (1.56±0.20) and iNOS mRNA (2.01±0.12) in the peri-infarct cortex of ED group were lower than those in the MCAO group ( (5.12±0.24), ( 8.15±0.22), (6.03±0.13), (7.20±0.09) ) ( t=7.86, 16.88, 16.55, 37.25, all P<0.05) and Eda group ( (2.85±0.07), (5.43±0.26), (2.67±0.27), (3.58±0.11) ) ( t=3.71, 9.41, 4.13, 11.30, all P<0.05). The level of CD206 mRNA in the peri-infarct cortex of the ED group (3.98±0.25) was higher than that in the MCAO group (2.00±0.11) ( t=7.08, P<0.05) and Eda group (3.17±0.09) ( t=3.25, P<0.05). (4) The results of immunofluorescence staining showed that the ratio of polarized M1 microglia in the peri-infarct cortex and striatum in the ED group ((20.36±9.23)%, (18.26±5.98)%)were lower than those in the MCAO group ( (83.69±12.79)%, (61.25±33.26)%) ( t=5.23, 3.02, both P<0.05) and Eda group((42.16±13.13)%, (40.23±14.22)%)( t=3.12, 2.08, both P<0.05). In addition, the number of neurons marked with MAP2 of peri-infarct cortex in the MCAO group was lower than that in the sham group( t=8.02, P<0.05), and the number of neurons marded with MAP2 of peri-infarct cortex in the ED group ((53.07±17.90) /scope) was higher than that in the MCAO group ( (26.27±9.95) /scope) ( t=6.89, P<0.05) and Eda group ( (38.69±12.03)/scope) ( t=5.26, P<0.05). (5) The results of TTC staining showed that the cerebral infarction volume in ED group ( (10.31±1.03)%) was lower than that in the MCAO group ( (34.71±1.74)%) ( t=15.31, P<0.05) and Eda group ( (26.05±1.00)%) ( t=9.88, P<0.05). Conclusion:Edaravone dexborneol can alleviate anxiety and depression in rats with cerebral ischemia-reperfusion, which may be related to the inhibition of M1 microglial polarization, the down-regulation of NF-κB signaling pathway and the enhancement of neuronal structural stability.