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Isoliquiritigenin is a flavonoid commonly found in liquorice and has been identified as a potent anti-tumor agent. The aim of this study was to investigate whether isoliquiritigenin regulates the proliferation and apoptosis of tongue squamous cell carcinoma cells by regulating forkhead box G1 expression via miR-21. MTT assay and flow cytometry were used to analyze cell proliferation and apoptosis, respectively. Quantitative real time polymerase chain reaction and western blotting were used to detect mRNA and protein expression levels, respectively. The relationship between miR-21 and forkhead box G1 was detected by dual luciferase assay. Isoliquiritigenin inhibited proliferation and induced apoptosis of tongue squamous cell carcinoma cells, and decreased miR-21 levels and promoted forkhead box G1 expression. Forkhead box G1 was then identified as a target of miR-21 and ISL could promote forkhead box G1 expression by inhibiting miR-21. Further analysis suggested that upregulation of miR-21 improved proliferation and suppressed apoptosis of tongue squamous cell carcinoma cells by inhibiting forkhead box G1 expression. Finally, our results revealed that isoliquiritigenin inhibited proliferation and induced apoptosis of tongue squamous cell carcinoma cells by regulating miR-21. Isoliquiritigenin might act as a novel therapeutic treatment for tongue squamous cell carcinoma cells through up-regulation of forkhead box G1 expression via inhibiting miR-21expression.

The wear-resistant tin bronze (Cu-10Sn-4Ni-3Pb) with tin content above 8 wt.% prepared by traditional melting and casting process usually defects such as low density, poor properties and segregations. The crystallization under pressure processing of Cu-10Sn-4Ni-3Pb alloy was investigated. The microstructures were observed and analyzed and compared with that by traditional melting and casting process. The results show that the dendrite has obviously disappeared and the dendritic segregation alleviated by using the crystallization under 680 MPa pressure process, in comparison with the remarkably dendrite microstructure and severe as-cast defects of alloy prepared by traditional melting and casting technology. Based on the experimental study, the properties and microstructures of Cu-10Sn-4Ni-3Pb tin bronze prepared by crystallization under pressure have been improved significantly.

According to the high-tin wear-resisting Cu-Sn-Pb-Ni alloy which the tin contents are 9~11%, the alloy casting were prepared by adding 0.5% refiner in melting precess and pouring in metal mold. The density, hardness, strength and elongation of alloy castings which adding refiner in melting process or not were tested and the casting mircostructure was analyzed. The results show that the density and hardness of Cu-Sn-Pb-Ni alloy casting prepared by adding refiner in melting process are 8.9083g/cm3 and 113HB separately, the strength and elongation are 314.7MPa and 32.7% respectively, comparison with the strength and elongation of non-refiner are 252MPa and 7.3% separately, they were increased by 24.9 % and 348 % respectively. The dendrite structure which are mainly α solid solution and eutectoid（α+δ）of casting prepared by non-refiner is relatively obvious, The grain are obviously refined and the distribution of lead simple substance phase are more dispersed among the grain and grain boundary by adding refiner in melting process.

The kinetics of transformation of 1,3,4,7-tetramethylisoindole (1) to 1,3,4,7-tetramethyl-1H−isoindole (2) in water or in deuterium oxide at various pH or pD at 25°C were measured spectrophotometrically. The results indicated that the transformation of 1 to 2 could be promoted by acid and base. From the solvent isotope effects and the fact that the 1-position of isoindole nucleus is electron-rich, the mechanism of this transformation is suggested.

A series of benzophenone (BP) and norbornadiene (NBD)-labeled poly(aryl ether) dendrimers (Gn-NBD), generations 1-4, were synthesized, and their photophysical and photochemical properties were examined. The phosphorescence of the peripheral BP (donor) chromophore was efficiently quenched by the NBD (acceptor) group attached to the focal point. Time-resolved spectroscopic measurements indicated that the lifetime of the triplet state of the BP chromophore was shortened due to the proximity of the NBD group. Selective excitation of the BP chromophore resulted in isomerization of the NBD group to quadricyclane (QC). All of these observations suggest that an intramolecular triplet energy transfer occurs in Gn-NBD molecules. The light-harvesting ability of these molecules increases with generation due to an increase in the number of peripheral chromophores. The energy transfer efficiencies are ca. 0.97, 0.54, 0.45, and 0.37 for generations 1-4, respectively, and the rate constant of the triplet-triplet energy transfer is ca. 10(6)-10(7) s(-1), which decreases inconspicuously with increasing generation. The intramolecular triplet energy transfer is proposed to proceed mainly via a through-space mechanism involving the closest donor (folding back conformation) and acceptor groups.

The charge-transfer complexes (CTC) between a parent molecule of antipsychotic pharmaceuticals, phenothiazine, and seven unsaturated acid anhydrides, 1,4,5,8-naphtalenetetracarboxylic dianhydride, diphenic anhydride, maleic anhydride (MA), 3,4,5,6-tetrahydrophthalic anhydride (THPA), 3-hydroxy-1,8-naphthalic anhydride (HONA), 4-chloro-1,8-naphthalic anhydride (ClNA), and 1,8-naphthalic anhydride (NA) were studied using IR and UV spectroscopy. Stability constants (K) at different temperatures were measured, and based on the K's DeltaH and DeltaS were calculated. The values of electron affinity (E(A)) of anhydrides were obtained according to Mulliken's theory. The results show that phenothiazine is an excellent donor and has strong ability to complex with the carbonyl group, and the E(A) values have good linear relationships with DeltaH and K, respectively. The solvent effect on CTCs was also determined and explained. The CTC of phenothiazine-succinic anhydride (SA) was studied under the same conditions. It was deduced from the results obtained that there were two charge-accepting centers in the unsaturated acid anhydrides when they formed CTCs with phenothiazine. The first one was carbon atom of the two carbonyl groups and the second one was their -C=C- in the molecules.

Values of second-order polarizabilities (beta(xxx)), the composite magnitude (beta(CT microg)) of molecular hypersusceptibilities and the second harmonic generation (SHG) of microcrystal were used to characterize and evaluate the second-order nonlinear optical performance of 10-hydrocarbylacridones. Using Nd:YAG as a laser source, the SHG values of these compounds in powder as compared with urea powder were obtained, compared with the calculated values of beta(CT microg) and beta(xxx) found by solvatochromic method. The results showed that the SHG values of compounds 1, 2, and 5 are larger than that of urea. Compound 5 has a highest beta(CT microg) value among the 12 compounds. Although the different electronegativities of hydrocarbyl (R) attached to nitrogen atom should have an effect on the extent of intralmolecular charge-transfer and further influence SHG, beta(CT microg) or beta(xxx) values, the relationships between electronegativity of R and SHG, beta(CT microg) or beta(xxx) could not be found. But it is found that the bigger the donating-electron ability of R, the longer the maximum absorption wavelength of 10-hydrocarbylacridone molecules.

ObjectiveTo investigate whether 4-month preoperative lanreotide treatment would improve the surgical cure rate of newly diagnosed acromegalic patients with macroadenomas.DesignA prospective, randomised study.MethodsAfter a baseline evaluation, patients were randomly assigned to 4-month preoperative treatment with lanreotide (starting with 30 mg/2 weeks i.m. and increasing to 30 mg/week i.m. at week 8 if mean GH >2.5 μg/l on GH day curves; pretreatment group, Group 1) or to transsphenoidal surgery (direct surgery group, Group 2). Cure was evaluated 4 months postoperatively primarily by fasting IGF1 less than or equal to age-adjusted upper limit of normal.ResultsA pool of 108 patients was randomly divided into two groups. Five patients in each group were lost to follow-up during the study period, so 49 patients in each group were analysed. At baseline, no difference was observed between the two groups. Cure was established in 24 of 49 (49.0%, 95% confidence interval (CI), 35.0–63.0%) pretreated patients (Group 1) versus 9 of 49 (18.4%, 95% CI, 7.6–29.2%) direct surgery patients (Group 2;P=0.001). Surgical morbidity was recorded in 12 patients (12.2%) and was similar in Group 1 and 2 patients (14.3 and 10.2% respectively;P=0.538). The postoperative hospital stay was similar between groups: being 4.5±1.6 days in Group 1 vs 4.8±1.9 days in Group 2 (P=0.328).ConclusionsPretreatment with lanreotide before transsphenoidal surgery improves surgical cure rates in patients with GH-secreting pituitary macroadenomas. Pretreatment does not affect surgical complications or duration of hospital stay (ClinicalTrials.gov number, NCT00993356).