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Two new ligands consisting of a fluorenyl and dioxotetraaza unit, namely, 2,10-diamino-6-(9H-fluoren-9-yl)-4,8-diazaundecane-5,7-dione (L1) and 1-(9H-fluoren-9-yl)-1,4,7,10-tetraazadecane-5,6-dione (L2) along with their copper(II) complexes have been synthesized. Their properties were examined by ES-MS and CV in aqueous solution and the crystal structure of the copper(II) complex of L1 has also been determined. The recognition of the transition metal ions (Cu2+, Ni2+, etc.) by receptors has been studied in aqueous solutions using pH-potentiometric and fluorimetric titrations. The results show that the binding of Cu2+ or Ni2+ ion with L1 leads to quenching of the fluorescence of the fluorenyl group, but on the contrary the fluorescence of L2 is enhanced. The mechanisms are discussed.

A new ligand consisting of fluorenyl and dioxotetraaza units, namely, 2,10-diamino-6-(9H-fluoren-9-yl)-4,8-diazaundecane-5,7-dione (L), and its nickel(II) complex were synthesized. The crystal structure of [Ni(H−2L)] showed that Ni(II) is in a square planar coordination environment. Studies of solution chemistry of the ligand and its nickel(II) complex indicate that the ligand can form a stable complex with Ni2+ ions and fluorescence quenching of the ligand is accompanied by the coordination of the metal ion to the dioxotetraaza unit and electron transfer from the Ni(II) center to fluorenyl in aqueous solution.

Electrospray mass spectrometry (ESMS) of a series of europium(III) supramolecules derived from tris(2-aminoethyl)amine (tren) and 2,6-diformyl-4-R-phenol (R = F, Cl, t-Butyl) is described. the peaks were assigned by both m / Z values and the isotope distributions. the ESMS are largely affected by the nature of the cryptates.

A new dioxotetraamine ligand 6-(9-fluorenyl)-1,4,8,11-tetraazaundecane-5,7-dione (L) and its copper(II) complex have been synthesized. Detailed studies have been made on solution chemistry of Cu(II), Ni(II) and Co(II) complexes of the ligand by pH-potentiometric and fluorimetric titration as well as cyclic voltammetry. The coordination of Cu2+ and Ni2+ quenches the fluorescence of fluorenyl in the ligand through an electron transfer mechanism. The crystal structure of [Cu(H−2L)] was determined.

Syntheses and crystal structures of tris[2-(1-naphthalenyloxy)ethyl]amine 1 and tris[2-(1-naphthalenyloxyl)ethyl]amine perchlorate 2 are reported. Compound 1 crystallizes in the rhombohedral system, space group R3¯ with a = 13.077(4), c = 29.011(8) A, and Dcalc = 1.233g/cm3 for Z = 6; compound 2 crystallizes in the cubic system, space group P213 with lattice parameters a = 14.630(5) A and Dcalc = 1.332g/cm3 for Z = 4. In 1, three naphthalene rings make dihedral angles of 109.21, 70.78, 70.78,° respectively. In 2 they make dihedral angles of 107.3, 72.7, 72.7° respectively. Deviation of N from the plane (C(12),C(12)i,C(12)ii) in 1 is 0.3742 A which is less than that in (2) (−0.4223 A). The crystals structure is stabilized by van der Waals interactions in both compounds.

Matrix metalloproteinases (MMPs) are involved in local invasion of ameloblastomas. This study was to evaluate the role of matrix metalloproteinase inducer (EMMPRIN) in angiogenesis in ameloblastomas by analyzing EMMPRIN expression and microvessel density (MVD) in ameloblastomas and odontogenic cysts.EMMPRIN expression and MVD in 41 specimens of ameloblastoma and 40 specimens of odontogenic cyst were examined by SP immuno-histochemistry.EMMPRIN was detected in all specimens of ameloblastomas and odontogenic cysts. The strong positive rate of EMMPRIN was significantly higher in ameloblastomas than in odontogenic cysts (85.4% vs. 62.5%, P0.05). MDV was positively correlated to EMMPRIN expression to some extent (r=0.677, P0.01).EMMPRIN may play an important role during the progression of ameloblastoma via controlling angiogenesis and degradation of extracellular MMPs.

Although 32P-glass microspheres (32P-GMS) have been used in internal radiotherapy for malignant tumors, it has been one of the key obstacles to improve the effect of radiotherapy. We investigated the cellular and hypersensitive effect of combined use of low dose of cisplatin and interstitial injection of 32P-GMS on mouse solid tumor S180.The mice with solid tumor S180 were randomly divided into four groups (controls, cisplatin therapy, 32P-GMS therapy and combination therapy). The specimens of the mice were sectioned two weeks after treatment and weighed. The death rate of tumor cells and the inhibition rate of tumor were calculated respectively. The cell cycle and apoptosis rate were evaluated with flow-cytometry. The ultrastructural changes of the four groups were observed by a transmission electron microscope. The data were analyzed by the chi-square test.The growth of tumor was slower in the combination therapy group than in the simple therapy groups by macrography. The inhibition rate and the death rate of tumor cells of the combination therapy group were significantly higher than those of the control group and the other two simple therapy groups (P0.05). More cell damages were displayed in the combination therapy group than in the other groups under the light and electronic microscope.Low-dose cisplatin combined with interstitial injection of 32P glass microspheres could be used as an effective hypersensitive regimen for the internal radiotherapy of mouse solid tumor S180.