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Activation of extracellular signal-regulated kinase (ERK) signalling, alteration of the uterine microenvironment and a reduction in human chorionic gonadotrophin production have been linked with fetal trisomy 16-induced early embryonic death (EED). However, the detailed biological mechanism of EED remains unclear. Using quantitative proteomics we successfully screened differentially expressed proteins in the villous tissues from patients with EED and fetal trisomy 16 (EEDT16), patients with EED but normal fetal chromosomes (EEDNC) and patients undergoing elective abortion with normal fetal chromosomes (EANC) as the reference group. Compared with the reference group, we identified 337 and 220 differentially expressed proteins in EEDT16 patients and EEDNC patients respectively; these were involved in critical biological processes including immune response, superoxide metabolism, inflammatory responses and so on. We found that differential expression of immunological function-related molecules, such as human leukocyte antigen-g (HLA-G), HLA-C, Fc Fragment Of IgG Receptor III (FcγR III), also named CD16, interleukin 18 (IL-18) and transforming growth factor β1 (TGF-β1), might induce EED in both EEDT16 and EEDNC patients. More severe immunological dysfunction was observed in EEDT16 patients than that in EEDNC patients. Furthermore, differential expression of implantation and invasion-related molecules, such as cytochrome b-245 light chain (CYBA), neutrophil cytosol factor 2 (NCF2), Mitogen-activated protein kinase kinase kinase 4 (MAP3K4), matrix metalloproteinase 2 (MMP2), MMP9 and tumour necrosis factor α (TNF-α) might induce EED in both EEDT16 and EEDNC patients, although more severe dysfunction in the implantation and invasion ability of villous tissues was observed in EEDT16 patients. Since the detailed biological mechanism of EEDT16 remains unclear, this study used quantitative proteomics to screen differentially expressed proteins in the villous tissues from patients with EEDT16, EEDNC and EANC. Dysfunction in immunological function and in the implantation and invasion ability was observed in EEDT16 and EEDNC patients. [ABSTRACT FROM AUTHOR]

In this study mercury sorbent based on manganese oxides impregnated γ-alumina was synthesized. Mercury retention characteristics were investigated by mercury speciation and thermal desorption experiments. No gaseous mercuric oxide was observed in mercury speciation experiments with a mercury mass balance ratio of 89.11%. Maximum mercury desorption peak at 480 °C indicated that mercury was adsorbed in the form of mercuric oxide. Three cycles of mercury retention were tested with different thermal treatment in-between to evaluate the cyclic performance. Changes in surface phase and manganese chemistry before and after thermal treatment were characterized by XRD and XPS. Deterioration in mercury retention capacity was observed after thermal desorption at 500 °C, which was interpreted with reduced initial adsorption rate calculated by Pseudo-second order kinetic model. XPS studies suggested that atomic ratios of Mn 4+ /(Mn 4+ +Mn 3+ ) decreased from 73.2% to 32.3% and 33.9% after thermal desorption in N 2 and air, respectively. The reduction of MnO 2 to Mn 2 O 3 was irreversible thus the mercury retention capacity could not be restored by thermal desorption at high temperatures. Spent sorbents that were reactivated at 200 °C in air without thermal desorption at 500 °C possessed considerable cycling performance for mercury retention due to the preserved Mn 4+ . [ABSTRACT FROM AUTHOR]

Highly curved buckybowls 3, 4, and 5 were synthesized from planar precursors, fluoranthenes 8, benzo[ k]fluoranthenes 10 and naphtho[1,2- k]-cyclopenta[ cd]fluoranthenes 12, respectively, using straightforward palladium-catalyzed cyclization reactions. These fluoranthene-based starting materials were easily prepared from 1,8-bis(arylethynyl)naphthalenes 6. Both buckybowls 3 and 4 are fragments of C60, whereas 5 is a unique subunit of C70. The curved structures were identified by X-ray crystallography, and they are deep bowls. The maximum π-orbital axis vector (POAV) pyramidalization angle in both 3 and 4 is 12.8°. Such a high curvature is very rarely obtained. Buckybowls 5 are less curved than the others because they have a lower density of five-membered rings, analogous to the tube portion of C70. Cyclopentaannulation increases the bowl depths of 3 and 4, but not the maximum POAV pyramidalization angle. Among the eight buckybowls studied herein, five form polar crystals. The bowl-to-bowl inversion dynamics of these buckybowls can be classified into two types; one has a planar transition structure, whereas the other has an S-shaped transition structure. A larger longitudinal length of these buckybowls corresponds to a stronger preference for the latter. The photophysical properties of these buckybowls were examined and compared with those of C60 and C70. Buckybowls 5 have absorption bands at wavelengths greater than 450 nm, which are similar to those of C70. The chiral resolution of the mono-substituted buckybowl 4 ac was also studied by using HPLC with a chiral column. [ABSTRACT FROM AUTHOR]

Two uracil derivatives of methyl 3-(5-fluoro-2,4-dioxo-3,4-dihydropyrimidin-1(2 H)-yl)propanoate ( 1) and methyl 3-(5-chloro-2,4-dioxo-3,4-dihydropyrimidin-1(2 H)-yl)propanoate ( 2) were synthesized and characterized by elementary analyses, MS, IR and NMR. The crystal structures of 1 and 2 were determined by means of X-ray diffraction. Compound 1 crystallized in the monoclinic P21/ c space group with a = 7.4213(9), b = 5.8480(7), c = 23.248(3) Å, and β = 108.184(4)°. Compound 2 crystallized in the monoclinic P21/ c space group with a = 12.5754(12), b = 4.9363(5), c = 16.5352(15) Å, and β = 97.455(3)°. The thermal stabilities of 1 and 2 were studied by DSC-TGA techniques. The UV spectra indicated that the two compounds interacted with DNA by electrostatic binding. Graphical Abstract: The X-ray diffraction revealed that the N-H···O inter-molecular hydrogen bond in solid state of the two title compounds resulted in antiparallel β-sheet arrangement.[Figure not available: see fulltext.][Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A novel cadmium metal-organic coordination polymer, namely Cd(atda)(3-abpt)(H2O)·2H2O (H2atda = (4-amino-1,2,4-triazole-3,5-diyldithio) diacetic acid, 3-abpt = 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole)), has been obtained under hydrothermal conditions by the reaction of cadmium salts with two kinds of organic ligands, characterized by single-crystal X-ray diffraction analysis, elemental analysis, and thermogravimetric analysis. Structural analysis reveals that complex possesses a 2D honeycomb network. Additionally, the complex show strong fluorescence in solid state at room temperature. [ABSTRACT FROM AUTHOR]

Two new binuclear complexes, Cd2(HL)2(NO3)4 · (CH3OH)2 (1) and Cu2(L)2(ClO4)2 (2), based on N'-(pyridin-2-ylmethylene)-2-(1H-1,2,4-triazol-1-yl)acetohydrazide (HL) and Cd(II) and Cu(II) salts have been synthesized and characterized by single crystal X-ray diffraction. Hydrogen bonds and π-π interactions extend both binuclear molecules, a 3-D supramolecular framework for 1 and 1-D staggered chains for 2. Fluorescence of both complexes is discussed. [ABSTRACT FROM AUTHOR]

A 3D complex [Cd(L)(4,4-bipy)].2H2O (1) has been synthesized by hydrothermal reaction of Cd(NO3)2, 4,4'-bipyridine and 1,2-bis[3-(1,2,4-triazolyl)-4-amino-5-carboxylmethylthio]ethane (H2L). X-ray crystal diffraction reveals that 1 belongs to triclinic system, [image omitted] space group. The crystallographic data are: a = 10.103(2) Å, b = 11.786(2) Å, c = 12.005(2) Å, α = 93.58(3)°, β = 98.66(3)°, γ = 105.47(3)°. In 1, Cd2+ ions are seven-coordinated and carboxylate groups adopt two coordination modes (bidentate chelate, bidentate chelate bridging) to connect Cd2+ ions forming a 2D layer. The auxiliary ligand 4,4'-bipy further link these 2D layers leading to a 3D network structure. Besides, the spectrum properties of 1 are investigated. [ABSTRACT FROM AUTHOR]

A coordination polymer, [Cu2(SCN)4(BPX)]n(BPX = 1,4-bis(pyridinium) xylol) was synthesized and characterized by IR spectrum, fluorescence spectrum and single crystal X-ray diffraction. Crystal structure revealed that the title compound crystallized in monoclinic system with space group P2(1)/c, a = 5.7540(7)Å, b = 12.7203(15) Å, c = 17.598(2) Å, β = 94.9940(10)°. Two SCN-ions served as bridging ligands to link two Cu(I) ions, giving rise to an eight-member ring. Furthermore, copper atom and sulfur atom of the eight-member ring bonded sulfur atom and copper atom of adjacent eight-member ring through the formation of Cu-S to form a small four-member ring. Thus, innumerable eight-member rings alternately linked four-member rings each other to form an infinite one-dimensional ladder-shaped structure. [ABSTRACT FROM AUTHOR]

Five binary silver(I) 3,5-di-substituted-1,2,4-triazolates ([Ag(3,5-R2-tz)], R = methyl, ethyl, propyl, isopropyl, phenyl) have been prepared and structurally characterised by X-ray single-crystal diffraction; X-ray analyses show that all of these complexes exhibit interesting 3D frameworks with different topologies. [ABSTRACT FROM AUTHOR]

Two new complexes [Ni(phen)(H2O)4] · (atda)(H2O)5 (1) and [Ni2(4,4' -bipy)2(H2O)8] · (atda)2 (2) (where H2atda = (4-amino-1,2,4-triazole-3,5-diyldithio)diacetic acid, phen = 1,10-phenanthroline, 4,4' -bipy = 4,4' -bipyridine) have been synthesized and characterized by elemental analysis, IR, UV, thermogravimetric analysis and X-ray diffraction technique. X-ray structural analyses reveal that the two complexes are both three-dimensional (3D) supramolecular structures and possess similar structural characters. The Ni(II) centers are both in distorted octahedral coordination environments, six-coordinated by four water molecules and two nitrogen atoms from a 1,10-phenanthroline molecule or two 4,4' -bipyridine molecules. The atda2 - ligands do not coordinate to the Ni(II) centers, but only exist as counter anions, forming hydrogen bonds with coordinated or uncoordinated water molecules. Various hydrogen-bonding interactions play an important role in the assembly of three-dimensional supramolecular architectures. [ABSTRACT FROM AUTHOR]

A new coordination compound, [Pb(phen)(NO3)3(H2O)]n(1), has been synthesized by the reaction of Pb(NO3)2 with phenanthroline (phen) in water. The complex was crystallized using the solution diffusion method and structurally characterized by X-ray single crystal diffraction. The compound 1 crystallizes in the monoclinic space group P21/c. In the structure unit of the compound 1, the central Pb(II) ion is six-coordinated with two nitrogen atoms from the phen, three oxygen atoms from three nitrate groups and one oxygen atom from a water molecule. The [Pb(phen)(NO3)2(H2O)] units are linked together by O1, N3, and O3 bridge from nitrate groups, resulting in the formation of one-dimensional chain structures. It is further connected by hydrogen bonds and π-π interactions formed a complicated supramolecular compound. In addition, the spectral properties and TG analyses for the compound 1 are also discussed The IR, UV-Vis spectra of the title compound as well as its thermodecomposition behavior were also discussed in detail in this paper. [ABSTRACT FROM AUTHOR]

A new two-dimensional supramolecular compound, {[Y(H[sub2]0)[sub8]](MHP)[sub2] (NO[sub3])[sub3]}[subn], was synthesized by the reaction of Y(NO[sub3])[sub3] 6H[sub2]0 with 4-methyl-6-hydroxypyrimidine (MHP) in methanol. It was characterized by single-crystal X-ray diffraction. Crystal data: triclinic, space group P-1 with a=9.908(2) A, b= 10.673(2) A, c= 12.408(3) A, *alpha;= 102.39(3)°, Β= 101.56(3)°, γ=90.31(3)°, Z=2. [ABSTRACT FROM AUTHOR]

Abstract: Four novel lanthanide(III) coordination polymers [Ln(L)1.5(H2O)2]·5H2O [Ln=Sm (1), Eu (2), Tb (3), Dy (4)] have been hydrothermally synthesized by the reaction of 1,2-bis[4-amino-5-carboxylmethylthio-(1,2,4-triazol-3-yl)]ethane (H2L) with lanthanide(III) salts, and structurally characterized by single crystal X-ray diffraction. Polymers 1–4 are isostructural, in which all the LnIII atoms are nine-coordinated and the carboxylate groups adopt three different coordination modes (bidentate chelate, bidentate bridging, bidentate chelate bridging) to connect LnIII atoms. These polymers exhibit 3D network structures with 2-fold interpenetration, in which intriguing 1D channels are observed. Besides, the spectra properties of the title polymers are investigated, the strong luminescence characteristics of 2–3 are found. [Copyright &y& Elsevier]

Abstract: Four novel coordination polymers, one-dimensional chains [M(PTE)2(N3)2] n (M=Mn for 1 and Co for 2), and two-dimensional layers [M(PTE)2(dca)2] n (M=Mn for 3 and Co for 4) (PTE=1-(2,4-difluorophenyl-2-(1H-1,2,4-triazol-1-yl)ethanone, dca=dicyanamide anion, N(CN)2 −), have been synthesized under mild ambient conditions and structurally characterized by single crystal X-ray diffraction. In all four crystal structures, the metal atoms adopt octahedral coordination geometry with six nitrogen atoms from two monodentate PTE ligands and four azido (or dca) bridging ligands. The crystal structures of 1 and 2 are isostructural 1-D polymeric chains, alternatively linked by double end-on and double end-to-end azido bridges. However, the bent dca ligands as bidentate μ2-1,5 bridging ligands interlink the octahedral metal units to lead to 2-D (4,4) grid networks in 3 and 4. Temperature-dependent magnetic measurements in 2–300K have been performed for these four polymers, and suggest alternative ferro- and antiferromagnetic couplings for end-on and end-to-end azido bridges in 1, and the dominant ferromagnetic coupling in 2, respectively. Both polymers 3 and 4 show weak antiferromagnetic exchanges through the μ2-1,5-dca bridges. The effects of auxiliary coligands on the structure and the nature of these magnetic exchanges are discussed in the light of the crystal structures in detail. [Copyright &y& Elsevier]

Abstract: A novel tetranuclear silver(I) heterocyclic cluster, which is of nano-hole structure, based on 1,1′-bis[(2-hydroxybenzylidene)thiocarbonohydrazono-1-ethyl] ferrocene (FcL) has been prepared and structurally characterized by single-crystal X-ray diffractions. In addition, its electrochemical properties are also discussed. The results confirm that the receptor FcL is responsive to Ag+. [Copyright &y& Elsevier]