RESUMEN
To investigate the variations and sources of n-alkanes and sugars in Taian City during summer, PM2.5 samples were collected from July 22 to August 19, 2016. The identified n-alkane and sugar sources were investigated using a principal component analysis (PCA) multiple linear regression (MLR) model and a backward trajectory model. The results showed that the mass concentrations of PM2.5 during summer were (37.2±11.5) µg·m-3. The mass concentrations of n-alkanes were (83.3±34.7) ng·m-3, the carbon preference index (CPI) was 1.83, and the relative contribution of wax n-alkanes was 34.7%-69.4%, suggesting that contributions from terrestrial plants were more significant in Taian City. The results showed that the mass concentrations of sugars in Taian City during summer were (73.4±46.6) ng·m-3. Levoglucan, galactosan, and mannosan were the main saccharides, accounting for 64.0%, 7.1%, and 6.3% of the total concentrations of sugars, respectively, indicating that biomass burning is much more significant in Taian City. The results of the PCA-MLR model suggested that n-alkanes and sugars in Taian City during summer were mostly from terrestrial plants, coal burning and biomass burning. The backward trajectory model showed that the pollution mostly came from the native sources of Shandong province and the inland cities in the south.
RESUMEN
OBJECTIVE@#To observe the effect of early intervention of bone-nearby acupuncture (BNA) combined with electroacupuncture (EA) on the expression of histone deacetylase1(HDAC1), histone deacetylase 2 (HDAC2) andμ-opioid recepter (MOR) in dorsal root ganglia (DRG) of bone cancer pain-morphine tolerance (BCP-MT) rats, and to explore its possible mechanism.@*METHODS@#A total of 35 SD rats were randomized into a sham BCP group (=6), a BCP group (=7), a MT group (=7), a BNA+EA group (=8) and a shame BNA group (=7). Except of the sham BCP group, cancer cell inoculation operation at left tibia was given in the other 4 groups to establish the bone cancer pain model. In the MT group, the BNA+EA group and the shame BNA group, intraperitoneal injection of morphine hydrochloride was given to establish the morphine tolerance model. After the operation, bone-nearby acupuncture combined with electroacupuncture was applied at "Zusanli" (ST 36) and "Kunlun" (BL 60) in the BNA+EA group, with dilatational wave, 2 Hz/100 Hz in frequency, 0.5 to 1.5 mA in intensity. Intervention in the shame BNA group was applied at the same time and acupoints as those in the BNA+EA group, the needles were pierced the skin without any electrical stimulation. The needles were retained for 30 min, once a day for continuous 7 days in both BNA+EA and shame BNA groups. Before and 10, 11, 15, 22 days after the operation, the left paw withdrawal threshold (PWT) was measured in the 5 groups. The levels of HDAC1, HDAC2 and MOR in DRG were detected by Western blot.@*RESULTS@#Ten days after the cancer cell inoculation operation, the PWT of the BCP, MT, BNA+EA and sham BNA groups was decreased compared with the sham BCP group (0.05); the PWT of the BNA+EA group was increased compared with the MT and sham BNA group (<0.01). In the BCP group, the DRG levels of HDAC1 and HDCA2 were increased, while the level of MOR was decreased compared with the sham BCP group (<0.05, <0.01). In the MT group, the DRG level of HDAC1 was increased compared with the BCP group (<0.05). In the BNA+EA group, the DRG level of HDAC1 was decreased compared with the MT group and the sham BNA group (<0.01, <0.05), while the level of MOR was increased (<0.01).@*CONCLUSION@#Early intervention of bone-nearby acupuncture combined with electroacupuncture can relieve the morphine tolerance in bone cancer pain rats, it may relate to down-regulating the expression of HDAC1 and up-regulating the expression of MOR in the dorsal root ganglia.