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In order to reduce the environmental pollution on the preparation process of aliphatic polycarbonate. The method that aliphatic polycarbonates were prepared via ring-opening polymerizations of propylene carbonate catalyzed by ionic liquids was presented. The acidity strength of ionic liquids and its influence on conversion, the content of carbonate units and molecular weight were investigaaed. The acidiiy strength of ionic liquids had been studied by IR spectra technique using pyridine as a probe molecular. Aliphatic polycarbonates can be prepared via ring-opening polymerizations oo propylene carbonate caaalyzed by ionic liquids [Bpy] Cl-(ZnCl2)x with different Lewis acidity. The reactions accompanied with the oligomerization, decarboxylaton and chain cleavage reaction. Ionic liquids can be separated, recovered and recycling-used with no volatilization, no inflammable and explosive. It is not easy oxidation, and has high thermal stabilitt and chemical stabiliit, It is a good method to make aliphatic polycarbonate puriiy. [ABSTRACT FROM AUTHOR]

To propose a rational construction, pair type, numbers and suitable size assortment, a kind of swing arm of an aerial platform truck was analyzed. The synthesis of mechanism was done to the starting position of connecting rod hinge point, corresponding corner of side links and length of the rack of the planar integrated linkage according to the kinematics or dynamics given requirements. The link combination types for six-bar linkage were selected and four combining forms were generated, then based on the forms, kinematic chain was regenerated and new mechanisms was produced, which gave a variety of possible configurations and completed the structural synthesis for the arm institution. The optimal solution is finally given after comparing the different schemes. [ABSTRACT FROM AUTHOR]

Objective: To investigate the expression of DAB2IP in bladder transitional cell carcinoma (BTCC) and its correlation with clinical characteristics and prognosis of BTCC patients., Methods: Immunohistochemical staining was applied to detect DAB2IP protein level in 79 cases of TCCB tissues and 11 cases of normal bladder tissues, and the relationships of the staining results with pathological grade, stage, lymph node metastasis, gender, age and the 3-year survival rate of the patients were analyzed., Results: The expression of DAB2IP in BTCC tissues was significantly lower than that in normal bladder epithelium, and the expression score and rate of DAB2IP in the high-grade, invasive and metastatic BTCC were significantly lower than those in low-grade, superficial and non-metastatic BTCC (P < 0.05). The 3-year survival rate of the patients with high DAB2IP expression was significantly higher than that of the patients with low DAB2IP expression., Conclusion: DAB2IP may be one of the important inhibitory factors during the occurrence and progression of BTCC.

Objective: To investigate the role of the hedgehog (HH) signaling pathway transcription factor glioma-associated oncogene hoinolog 1 (GLI-1) in EGF-regulated enhancement of the invasiveness of the prostate cancer ARCaP(E) cell line in vitro., Methods: The expressions of EGFR and GLI-1 in prostate cancer ARCaP(E) cells were analyzed by immunofluorescence staining. ARCaP(E) cells were treated with EGF at 100 ng/ml, followed by detection of the changes in cell morphology and invasiveness, as well as in the expressions of p-ERK, ERK and GLI-1. Migration transwell assay was used to determine the effects of 100 ng/ml EGF and GLI-1 antagonist GANT61 on the invasiveness of the ARCaP(E) cells., Results: Both EGFR and GLI-1 were expressed in the ARCaP(E) cells. EGF induced morphological transition of epithelial-like ARCaP(E) cells to mesenchymal-like cells, increased their in vitro invasiveness, and significantly upregulated the expressions of p-ERK and GLI-1 in the ARCaP(E) cells (P<0.05). GANT61 significantly inhibited the in vitro invasiveness of the ARCaP(E) cells and reduced the enhancing effect of EGF on their invasiveness (P<0.05)., Conclusion: The results from ARCaP(E) cells shed light on the cross-talk of the HH pathway with the EGF/ERK signaling pathway. GLI-1 might be responsible for EGF-regulated enhancement of the invasiveness of ARCaP(E) cells in vitro.

Objective: To investigate the role and significance of epithelial-mesenchymal transition (EMT) and its transcriptional regulator Twist1 in the development of the human fetal prostate., Methods: Twenty-five human fetal prostate specimens at various developmental stages (16-39 weeks) were included in this study. EMT markers, such as E-Cadherin, N-Cadherin and Vimentin, and EMT transcriptional regulator Twist1 were determined by immunohistochemistry, and their relationship with the development of the human fetal prostate was analyzed., Results: E-Cadherin was expressed in the fetal prostate epithelium only, while Vimentin, N-Cadherin and Twist1 in both the epithelium and the stroma. The expression of E-Cadherin gradually increased, but those of Vimentin, N-Cadherin and Twist1 gradually decreased with the gestation stages. No significant changes were observed in the staining patterns of Vimentin, N-Cadherin and Twist1 in the stroma during the whole developmental process., Conclusion: EMT is involved in the development of the human fetal prostate, which may promote epithelial cell motility to form prostatic bud tubules in early gestation stages and boost the differentiation of prostate epithelia in later stages.

The mol-ecule of the title compound, C(18)H(19)N(3)O, displays a trans configuration with respect to the C=N double bond. There is a strong intra-molecular O-H⋯N hydrogen-bonding inter-action between the hydr-oxy group and imine N atom. The dihedral angle between the aromatic rings is 30.35 (8)°. The crystal packing is stabilized by O-H⋯N links.

In the mol-ecule of the title compound, C(28)H(32)N(2), the benzimidazole ring system is almost planar [maximum deviation = 0.0221 (15) Å] and forms dihedral angles of 85.86 (4) and 32.09 (6)° with the benzene rings. In the crystal structure, mol-ecules are linked into chains running parallel to the a axis by inter-molecular C-H⋯N hydrogen bonds. The methyl groups of a tert-butyl group are rotationally disordered over two positions with refined site-occupancy factors of 0.636 (4) and 0.364 (4).

The mol-ecule of the title compound, C(15)H(12)N(2)O(2), displays a trans configuration with respect to the C=N double bond. The dihedral angle between the two benzene rings is 30.46 (14)°. A strong intra-molecular O-H⋯O hydrogen bond stabilizes the mol-ecular structure.

The title compound, C(18)H(12)N(2)O, crystallizes in a phenol-imine tautomeric form with a Z conformation for the imine functionality. The dihedral angle between the aromatic rings is 8.98 (9)°. A strong intra-molecular O-H⋯N hydrogen-bond inter-action between the hydroxyl group and imine N atom occurs.

In the mol-ecule of the title compound, C(15)H(12)N(2)O(2), the aromatic rings are oriented at a dihedral angle of 28.11 (3)°. Intra-molecular O-H⋯N hydrogen bonding results in the formation of a planar six-membered ring, which is nearly coplanar with the adjacent ring at a dihedral angle of 1.53 (3)°. In the crystal structure, π-π contacts between the benzene rings [centroid-centroid distance = 3.841 (1) Å] may stabilize the structure.