OBJECTIVETo research the regulation of transmembrane transport activity of paclitaxel influenced by fangchinoline in MDR1-MDCK II cells.

METHODPaclitaxel, one of the substrate of P-gp, was selected as the model drug. Verapamil hydrochloride was adopted as the active control to investigate the bilateral transport activity of paclitaxel regulated by fangchinoline in MDR1-MDCK II cells. RP-HPLC was applied to determine the concentration of paclitaxel in the transporting medium, which was used to calculate apparent permeability coefficient of paclitaxel across MDR1-MDCK I1 monolayer cells.

RESULTThe efflux rate of paclitaxel was faster than the absorption rates across the MDR1-MDCK II monolayer cells with highly expressed P-gp. The absorption rates of paclitaxel combinated with fangchinoline and verapamil hydrochloride respectively were remarkably increased and the efflux rate was decreased. The reversal effect of the fangchinoline was stronger than the verapamil hydrochloride with the same molar concention.

CONCLUSIONFangchinoline can apparently decrease the efflux of paclitaxel and inhibit the multidrug resistance of antitumor drug mediated by P-gp.

ATP Binding Cassette Transporter, Sub-Family B ; ATP-Binding Cassette, Sub-Family B, Member 1 ; genetics ; metabolism ; Animals ; Benzylisoquinolines ; pharmacology ; Biological Transport ; drug effects ; Cell Line ; Cell Membrane ; drug effects ; metabolism ; Cell Membrane Permeability ; drug effects ; Dogs ; Humans ; Models, Biological ; Paclitaxel ; pharmacokinetics ; Plant Extracts ; pharmacokinetics

Objective: To investigate the effect of self-etching adhesive with different unsealing time on the microleakage of the adhesive interface between tooth and resin. Methods: Unopened self-etching adhesives, Scotchbond Universal (S) and Xeno V+ (X) were respectively used to adhere Z350 resin for restoration of the prepared occlusal cavities sized 4 mm × 4 mm × 4 mm (n = 40) . The methylene blue staining method was used to observe the microleakage of the adhesive interface between the tooth and filling material at the instant moment, 1, 2 and 3 months after the self-etching adhesives was opened (n = 10) . Results: (1) Increase of microleakage in S group was found with the time span after unsealing, and there was a statistical difference between the instant moment and 3 months after unsealing (P＜0. 05) . (2) There was no significant difference at the 4 test time points in X group (P＞0. 05), although the microleakage value of the samples were increased with the increase of the time after unsealing. (3) The microleakage of X group was greater than that of S group at the instant moment and 1 month after unsealing (P＜0. 05) . Conclusion: Unsealing time may increase the microleakage of the adhesive interface between the tooth and the filling material, the effect varies with the types of the adhesives.

Objective To investigate the expression of lncRNA SNHG8 in placenta accrete(PA)and its effect on trophoblast invasion and migration.Methods qRT-PCR was used to detect the expression of lncRNA SNHG8 in placenta tissue of 30 cases in PA group and 30 cases in control group,and the correlation between lncRNA SNHG8 expression and prenatal ultrasound score of 30 cases in PA group was analyzed.Transwell and scratch assay were used to detect the effect of lncRNA SNHG8 interference on the invasion and migration of human chorionic trophoblast cells(HTR8/SVneo cells),and western blot was used to detect the expression of MMP-2 and MMP-9.The downstream targets of lncRNA SNHG8 were predicted by StarBase software,and the expression of lncRNA SNHG8 was detected in placental tissues of the two groups.Dual luciferase reporter assay was used to detect the targeting relationship between lncRNA SNHG8 and miR-542-3p.Results Compared with that of the control group,the expression of lncRNA SNHG8 was up-regulated in the placenta tissue of the PA group(P<0.05),and it was positively correlated with prenatal ultrasound score.Interference with lncRNA SNHG8 inhibited the invasion and migration of trophoblast cells(P<0.05);the protein expression of MMP-9 and MMP-2 also decreased signifi-cantly(P<0.05).Biological prediction indicates that miR-542-3p had a binding site with lncRNA SNHG8,and miR-542-3p expression was down-regulated in PA placental tissue(P<0.05).Dual luciferase reporter assay confirmed that lncRNA SNHG8 could target miR-542-3p.Compared with si-SNHG8+inhibitor-NC,co-transfection of si-SNHG8 and miR-542-3p inhibitor enhanced the invasion and migration ability of trophoblast cells(P<0.05).Conclusion lncRNA SNHG8 is highly expressed in PA and is related to the severity of PA.LncRNA SNHG8 promotes the invasion and migration of trophoblast by regulating the level of miR-542-3p.The study suggests that lncRNA SNHG8 plays an important role in the invasion and migration of PA trophoblast cells,which is expected to be a clinical diagnostic biomarker and therapeutic target.

Objective:To investigate the effect of BMAL1 gene on the proliferation, migration and invasion ability of radiation-resistant nasopharyngeal carcinoma cell line (5-8FR) and the molecular mechanism. Methods:A multi-target click model was constructed for radiation-resistant nasopharyngeal carcinoma cell line 5-8FR by low-dose fractionated irradiation, and the results of clone formation assay were used to fit the multi-target click model and calculate the sensitization ratio of radiotherapy. The expression levels of PI3K/Akt/MMP-2/9 signaling pathway-related proteins in 5-8FR and control 5-8F cell lines were detected by Western blot. The overexpression and knockdown vectors of BMAL1 gene were constructed and transfected with 5-8F and 5-8F cell lines, respectively. The BMAL1 gene overexpression (pcDNA-BMAL1) and its control (pcDNA) and interference (BMAL1-shRNA) and control (con-shRNA) cell lines were stably transfected with nasopharyngeal carcinoma cell line 5-8F and radiation-resistant cell line 5-8FR, respectively. Western blot was performed to verify the infection efficiency and detect the changes of PI3K/Akt/MMP-2/9 signaling pathway-related proteins after overexpression or interference of BMAL1 gene in both groups of cells. CCK-8 assay, cell scratch test and Transwell chamber test were conducted to investigate the proliferation, migration and invasion capabilities of 5-8FR cell line after overexpression or interference of BMAL1 gene. Results:BMAL1 gene expression was down-regulated, and those of PI3K/Akt pathway proteins and downstream related molecules of MMP-2 and MMP-9 were up-regulated, and TIMP-2 and TIMP-1 expression was down-regulated in nasopharyngeal carcinoma radiation-resistant cell lines. Overexpression of BMAL1 gene inhibited the expression of PI3K/Akt pathway proteins and downstream related molecules of MMP-2 and MMP-9, promoted the expression of TIMP-2 and TIMP-1, and inhibited the proliferation, migration and invasion capabilities of radiation-resistant nasopharyngeal carcinoma cells, while interference with BMAL1 gene yielded the opposite results. Conclusions:BMAL1 gene can reverse the expression of PI3K/Akt/MMP-2/9 signaling pathway-related proteins in radiation-resistant nasopharyngeal carcinoma cell lines and inhibit the proliferation, migration and invasion capabilities of radiation-resistant nasopharyngeal carcinoma cell lines.

Objective:To investigate the efficacy and safety of SIMI mouthguard paint(test group) in the treatment of enamel demineralization during orthodontic therapy with fixed applince.Methods:152 cases underwent orthodontic therapy with fixed applince were included in a randomized,open,positive control trial,and were treated by SIMI and Duraphant fluoride toothpast (control group) respectively(n =76).The enamel opaque spot was observed before and 3 months after using the products.The oral mucosa reactions,asthma attacks or stomach nausea and other adverse events were recorded.Results:150 cases (n =75) completed the trial.The results showed that the test group was non-inferior compared with the control group.No adverse event was found in both groups.Conclusion:SIMI mouthguard paint is effective in control of enamel demineralization during orthodontic therapy with fixed applince.

Arginine kinase (AK) is a key enzyme in energy metabolism of invertebrates and plays an important regulatory role in the life activities such as growth and development, nutrition utilization, immune resistance and stress response. Arginine kinase of Bombyx mori (BmAK) is related to the energy balance and anti-NPV process, but there is little research on its molecular structure and enzymatic properties. We cloned the ORF sequence of BmAK gene, and analyzed chromosomal localization, genomic structure, mRNA structure, secondary and tertiary structure. Phylogenetic analysis indicated that AK was highly conserved in evolution. Soluble recombinant BmAK was obtained by prokaryotic expression, and purified by Ni-NTA affinity chromatography. The circular dichroism spectroscopy showed that BmAK contained α-helix structures, and its α-helix structures were relatively stable in the pH range between 5 and 10. Enzyme activity analysis showed that the optimum temperature of BmAK was 30 ℃ and the optimum pH of BmAK was 7.5. The optimal temperature of BmAK was 25 ℃. Between 15 ℃ and 30 ℃, the structure and activity of BmAK was relatively stable. The structure of BmAK was relatively stable at pH 7.0. Our findings reveal the structure and function of BmAK to develop novel green safe and environmentally friendly insecticides.

With basal medium, we studied the growth status, lipid droplet distribution, total lipid content of Chlorella protothecoides CS-41 treated with different concentrations of sodium chloride (0, 150, 300 and 600 mmol/L) by optical microscopy, electron microscopy, confocal laser focusing and Nile red staining. Results show that the addition of NaCl affected the growth of Chlorella protothecoides CS-41. With the increase of NaCl concentration, the growth rate of Chlorella was inhibited. Chlorella cell wall became thicker, and lipid droplets increased. At the early stage, the amount of lipid droplets in the 600 mmol/L NaCl culture was the highest, but at the late-log stage, the amount of lipid droplets increased with the increase of the biomass of culture in 150 and 300 mmol/L NaCl culture. At the stable stage, biomass (dry weight) in 300 mmol/L NaCl culture was 73.55% of that in the control, but the total lipid content was 2.22 times higher than that in the control. A certain concentration of sodium chloride treatment can significantly increase the lipid content of Chlorella protothecoides CS-41.