A TurboFlow ( TF ) online purification-ultra performance liquid chromatography-tandem mass spectrometric method was developed for the determination of nitroimidazoles and their metabolites ( ornidazole, IPZ, MNZ, MNZOH, DMZ, RNZ, IPZOH and HMMNI) in honey. The honey sample was extracted by H2 O containing 0. 1% formic acid solution. Then, the extraction solution was analyzed by TF-UPLC-MS/MS. The main factors influencing the purification efficiency including TF column, mobile phases and elution solutions were optimized. The compounds were detected by selective reaction monitoring ( SRM) in positive ion mode electrospray ionization ( ESI+) . The linear range of the method ranged from 0 . 1 to 50μg/L for nitroimidazoles and their metabolites, with the correlation coefficient ( R2 ) of over 0. 997. The limits of quantification were 0. 1 μg/kg for ornidazole, IPZ, 0. 2 μg/kg for MNZ, MNZOH, DMZ, RNZ and IPZOH, and 1. 0 μg/kg for HMMNI, respectively. The recoveries were in the range of 73. 7% to 116. 4% at four spiked levels with the relative standard deviations ranged from 1. 1% to 9. 1% in honey samples. The results indicate that the developed method is simple, efficient and precise, and can be used for the determination of nitroimidazoles and their metabolites in the actual honey samples.

Objective To investigate the effects of selective cyclooxygease-2 inhibitor on pulmonary surfactant protein(SP-B) and transforming growth factor(TGF-β1) of hyperoxic lung injury in newborn rats.Methods One hundred and five SD rats were randomly divided into 3 groups (35 cases in each group):air group (group Ⅰ),in which the rats were exposed to room air;hyperoxia group(group Ⅱ),in which the rats were exposed to hyperoxia(850 mL/L oxy gen);Celecoxib group(group Ⅲ),in which the rats were exposed to heyperoxia(850 mL/L oxygen) and intraperitoneally injected with 5 mg/kg Celecoxib.The lungs of rats were removed on 3 d,7 d,14 d after birth and the following indices were measured:lung section from the lower right lung were stained with HE,and the histological changes was examined;the contents of SP-B and TGF-β1 in the bronchoalveolar lavage fluid of left lung was determinated by using enzyme-linked immunosorbent assay (ELISA);right upper lung was immunohistochemically stained to measure the contents of SP-B and TGF-β1,quantitative real-time PCR(RT-PCR) was used to detect the mRNA expression of SP-B and TGF-β1.Results There were no inflammatory cells and exudation in the lung in group Ⅰ;in group Ⅱ,the structure disorder,pulmonary edema,and inflammatory infiltrates were found;but the damage was obviously alleviated in group Ⅲ.Protein expression could be better detected by ELISA,at the time of 14 day,SP-B was expressed at different levels in3 groups:(29.93±6.40) ng/L in group Ⅰ,(18.20 ±3.70) ng/L in group Ⅱ and (19.63 ±10.20) ng/L in group Ⅲ,SP-B level in group Ⅱ was significantly lower than that in group Ⅰ (t =13.152,P ＜ 0.01),and the expres sion in group Ⅲ was significantly higher than that in group Ⅱ (t =5.190,P ＜ 0.01).TGF-β1 was expressed at different levels in 3 groups:(34.73 ±2.30) μg/L in group Ⅰ,(41.66 ± 1.80) μg/L in group Ⅱ and (38.03 ±0.20) μg/L in group Ⅲ,and the level of TGF-β1 was significantly higher in group Ⅱ than that in group Ⅰ (t =6.584,P ＜ 0.01),but the expression of group Ⅲ was significantly lower than that in group Ⅱ (t =5.609,P ＜ 0.01).The expression of mRNA was detected by RT-PCR,and at the time of 14 day,SP-B mRNA was expressed at different levels in 3 groups:3.14 ±0.10 in group Ⅰ,0.81 ±0.06 in group Ⅱ and 1.12 ±0.06 in group Ⅲ,and SP-B level in group Ⅱ was significantly lower than that in the group Ⅰ (t =55.050,P ＜0.01),and the expression in group Ⅲ was significantly higher than that in group Ⅱ (t =10.305,P ＜ 0.01).TGF-β1 mRNA was expressed at different levels in the 3 groups:1.94 ±0.03 in group Ⅰ,13.26 ±0.43 in group Ⅱ and 6.49 ±0.26 in group Ⅲ,the level of TGF-β1 was significantly higher in group Ⅱ than that in group Ⅰ (t =75.471,P ＜ 0.01),while the expression of group Ⅲ was significantly lower than that in group Ⅱ (t =38.470,P ＜ 0.01).Conclusions Cyclooxygenase-2 inhibitor can attenuate hyperoxic lung injury in rats,and the mechanism might be related to the reduction of prostaglandin.

Objective:To explore the experience to reconstruct large nasal defects with combined local flaps after cutaneous tumor excision based on the aesthetic subunit principle.Methods:From May 2007 to May 2019, based on the nasal aesthetic subunit principle, combined local flaps were used to cover the large nasal defects in 21 cases of nasal tumors that were removed. Among 21 cases, there were 11 cases of basal cell carcinoma, 7 cases of squamous cell carcinoma, and 3 cases of pigmented naevus. The locations were dorsum of nose in 8 cases, nasal side in 7 cases, nasal ala in 5 cases, nasal tip in 1 case, and across two nasal subunits in 17 cases. The area of the defect ranged between 1.3 cm × 0.9 cm and 3.6 cm × 3.1 cm. A local combined skin flap was used to repair the skin defect. The secondary defect of donor site was directly sutured.Results:Among 21 cases, 20 cases acquired complete recovery; 1 case had epiderm necrosis over the far end of the flap achieved healing by the first intention. The nasal defect was successfully repaired in all patients, and the all flaps survived. A total of 21 patients were available for follow-up of 1 to 48 months, no tumor recurrence occurred, and the repaired tissues were well matched to the surrounding tissue, good nasal contour was obtained, and the cosmetic results were satisfactory.Conclusions:Based on the nasal aesthetic subunit principle, the combined local flaps can be used to reconstruct the large nasal defects, and the cosmetic results are satisfactory.