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Endogenous bacterial infections from damaged gastrointestinal (GI) organs have high potential to cause systemic inflammatory responses and life-threatening sepsis. Current treatments, including systemic antibiotic administration and surgical suturing, are difficult in preventing bacterial translocation and further infection. Here, we report a wireless localized stimulator composed of a piezo implant with high piezoelectric output serving as an anti-infective therapy patch, which aims at modulating the electro-microenvironment of biofilm around GI wounds for effective inhibition of bacterial infection if combined with ultrasound (US) treatment from outside the body. The pulsed charges generated by the piezo implant in response to US stimulation transfer into bacterial biofilms, effectively destroying their macromolecular components (e.g. , membrane proteins), disrupting the electron transport chain of biofilms, and inhibiting bacterial proliferation, as proven by experimental studies and theoretical calculations. The piezo implant, in combination with US stimulation, also exhibits successful in vivo anti-infection efficacy in a rat cecal ligation and puncture (CLP) model. The proposed strategy, combining piezo implants with controllable US activation, creates a promising pathway for inhibiting endogenous bacterial infection caused by GI perforation. [ABSTRACT FROM AUTHOR]

A modified method for the synthesis of pyrazolo[3,4- b ]pyrrolo[3,4- d ]pyridine was developed through an Aza-Diels–Alder reaction of pyrazoylimines with maleimides in the sealed tube. Based on the control experiment, the yields for the Aza-Diels–Alder reaction seemed proportional to the suitable torsion conformation of pyrazoylimine, which was modulated by N , N -disubstituted amidinyl moiety. The versatile sealed tube technique was also proved to promote the higher isolated yields in the Aza-Diels–Alder reaction. [ABSTRACT FROM AUTHOR]

Abstract: An efficient one-pot methodology for the synthesis of pyrazolo[3,4-d]pyrimidines was developed by using 5-aminopyrazoles with formamide in presence of PBr3 as the coupling agent. Among the examples presented in this work, compounds 41 and 54–56 with phenyl or 2-quinolinyl groups at N-1 and p-Me–Ph, p-Cl–Ph, or p-OMe–Ph group at C-3 position in the pyrazole ring possessed better potency against NCI-H226 and NPC-TW01 cancer cells with GI50 values between 18 μM and 39 μM. [Copyright &y& Elsevier]

Abstract: An efficient 1,3-dipolar cycloaddition method was performed for the synthesis of a series of monofluoro- and trifluoromethane-3,5-disubstituted 1,2,4-triazoles. This efficient cycloaddition method was to react hydrazonoyl hydrochlorides with a series of aldehydes in the presence of NEt3 as catalytic basic agent to provide the corresponding product in 28–94%. Their growth inhibitory results against cancer cells indicated that some of the fluorine- and trifluoromethane-containing compounds could effectively inhibit the growth of NCI-H226 and T-cell leukemia (Jurkat) cells. Among the compounds, trifluoromethane-containing 1,2,4-triazoles possessed the five-membered ring groups on the C-5 position of the triazolic ring, including cyclopentyl, 3-furyl, 3-thienyl, and 2-pyrrolyl, possessed the significant inhibitory activity for NCI-H226 cancer cells. [Copyright &y& Elsevier]

Abstract: A new ‘one-flask’ synthesis of 3,5-disubstituted 1,2,4-triazoles has successfully been developed to synthesize a series of 3,5-disubstituted 1,2,4-triazoles. The transformation involves the 1,3-dipolar cycloaddition reaction of hydrazonoyl hydrochlorides with oxime intermediates prepared from aldehydes with hydroxylamine hydrochloride in the presence of excess amount of triethylamine. In this ‘one-flask’ 1,3-dipolar reaction, hydrazonoyl hydrochlorides was concerned as the masked 1,3-dipole nitrilimine under basic condition. Furthermore, this newly developed methodology can be applied to various aldehyde substrates including aliphatic, cyclic aliphatic, aromatic, and heterocyclic aldehydes. [Copyright &y& Elsevier]

Abstract: It is known that estrogen promotes the proliferation of breast cancer cells. Agonists to P2Y2 receptors promote or suppress proliferation in different cancers. In the present study, the methods of methylthiazoltetrazolium (MTT) assay, real-time RT-PCR, Western blot and fluorescent calcium imaging analysis were used to investigate whether P2Y2 receptors play a role in the effects of estrogen on the breast cancer cell lines, MCF-7 and MDA-MB-231. We found that P2Y2 receptors were expressed in both the estrogen receptor alpha (ERα)-positive breast cancer cell line MCF-7 and the ERα-negative breast cancer cell line MDA-MB-231. 17β-Estradiol (17β-E2) (1pM to 1000nM) promoted proliferation of MCF-7 cells, which was blocked by the ER antagonist ICI 182,780 (1μM) and the ERα antagonist methyl-piperidino-pyrazole (MPP, 50μM), but not by the ERβ antagonist 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-3-yl]phenol (PHTPP, 50μM) or ERβ small interfering RNA. The P2Y2 and P2Y4 receptor agonist UTP (10–100μM) suppressed the viability of breast cancer cells in both MCF-7 and MDA-MB-231 cells. The effect was blocked by suramin (10–100μM), known to be an effective antagonist against P2Y2, but not P2Y4, receptor-mediated responses. 17β-E2 played a more positive role in promoting proliferation in MCF-7 cells when suramin blocked the functional P2Y2 receptors. 17β-E2 (0.1–1000nM) downregulated the expression of P2Y2 receptors in terms of both mRNA and protein levels in MCF-7 cells. The effect was blocked by ICI 182,780 and MPP, but not PHTPP or ERβ small interfering RNA. 17β-E2 did not affect the expression of P2Y2 receptors in MDA-MB-231. UTP (10–100μM) led to a sharp increase in intracellular Ca2+ in MCF-7 cells. Pre-incubation with 17β-E2 (0.1μM) attenuated UTP-induced [Ca2+]i, which was blocked by ICI182,780 and MPP, but not PHTPP. It is suggested that estrogen, via ERα receptors, promotes proliferation of breast cancer cells by down-regulating P2Y2 receptor expression and attenuating P2Y2-induced increase of [Ca2+]i. [Copyright &y& Elsevier]

Abstract: A new chelating radical ligand NIT-1′-MeBzIm (1) (NIT-1′-MeBzIm=2-{2′-[(l’-methyl)benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) and three corresponding complexes [M(NIT-1′-MeBzIm)2(NO3)(CH3OH)]·(NO3)(CH3OH) (M=Ni (2), Co (3)), [Zn(NIT-1′-MeBzIm)2(CH3OH)2]·(ClO4)2(H2O)2(CH3OH) (4) have been prepared and structurally characterized by X-ray diffraction method and variable-temperature magnetic susceptibility measurements. In the crystal structures, radical 1, complexes 3 and 4 crystallize isomorphously in monoclinic, with the space groups are P2(1)/n, P2(1)/c, and P2(1), respectively. Complex 2 crystallizes in orthorhombic space group Pna2(1). The metal ions of the three complexes embed in distorted octahedron geometry centers and coordinated by two NIT-1′-MeBzIm radicals from the equatorial positions to form trans configuration, the axial positions are occupied by one methanol molecule and one nitrate anion for 2 and 3, but by two methanol molecules for 4. Magnetic measurement demonstrates that the intramolecular exchange couplings in 2 and 3 are antiferromagnetic with J =−41.25 and −38.1cm−1, where the spin Hamiltonian is defined as Ĥ =−2J(Ŝ rad1 Ŝ M + Ŝ M Ŝ rad2) based on the molecular structure of radical-metal-radical, while that in 4 is weak ferromagnetic with J =1.65cm−1 where the spin Hamiltonian is defined as Ĥ =−2JŜ 1 Ŝ 2 within the complexes. Intermolecular exchange couplings in 1 is also weak ferromagnetic with J =1.32cm−1 where the spin Hamiltonian is defined as Ĥ =−2JŜ 1 Ŝ 2 between radical and radical. Compounds 2–4 exhibit intermolecular antiferromagnetic interaction with the zJ′=−0.52cm−1, θ =−0.75K and zJ′=−0.49cm−1 for compounds 2, 3 and 4, respectively, which should ascribe to the weak interactions. The crystal structures for 1–4 have intermolecular hydrogen bonding interactions (and π–π piling interactions for 1 and 3) which form the single crystals into 1-D, 2-D, 3-D structures and seems to play an important role in molecular packing and in magnetic coupling. [Copyright &y& Elsevier]

Abstract: Using Cu(II), Mn(II) or Co(II) salt and the flexible ligands, N-[(4-carboxyphenyl)-sulfonyl]glycine (H3L1) and N-[(3-carboxyphenyl)-sulfonyl]glycine (H3L2), a series of new coordination polymers, [Mn(phen)(H2O)4][HL1] (1), [Co3(L1)2(bipy)3(H2O)6] n ·8nH2O (2), [Cu4(L1)2(OH)2(bipy)4] n ·12nH2O (3), [Na(H2L1)(H2O)] n (4), [Mn2(HL2)2(dpe)3(H2O)2] n ·ndpe (5), (phen=1,10-phenanthroline, bipy=4,4′-bipyridine, dpe=1,2-di(4-pyridyl)ethylene), varying from 0D to 3D, have been synthesized and structurally characterized. Compound 1 has a [Mn(phen)(H2O)4]2+ cation and a HL1 2− anion. Compound 2 features a new 1D triple chain, based on octahedral cobalt atoms bridged by bipy molecules and terminally coordinated by two H3L1 ligands. Compound 3 has a 2D layered structure, constructed from new alternating chains where H3L1, hydroxyl and water molecules simultaneously act as bridging ligands. Compound 4 possesses a bilayer structure in which two adjacent layers are pillared by H3L1 ligands into a 2D bilayer network. Compound 5 is a unique 3D coordination polymer in which each Mn center binds two trans-located dpe molecules. The thermal stability as well as magnetic properties of 5 was also studied. This work and our previous work indicate that the positional isomer of the anionic N-[(carboxyphenyl)-sulfonyl]glycine is important in the construction of these network structures, which are also significantly regulated by the metal centers. [Copyright &y& Elsevier]

Abstract: Two complexes of formulas [Ni(IM-MeImz)2(SCN)2]·CH3CH2OH (1) and [Mn(IM-MeImz)2(SCN)2]·3H2O (2), where IM-MeImz=2-(5-Methylimidazol-4-yl)-4,4,5,5-tetramethyl-2-imidazoline-1-oxyl, have been synthesized and characterized by single-crystal X-ray diffraction. The X-ray analysis demonstrates that IM-MeImz ligand is coordinated to metal ion with the κ2 N(MeImz), O(IM) mode to avoid steric hindrance with the methyl group in complex. In the solid state, the complexes 1 and 2 are linked by intermolecular hydrogen bonds, leading to two-dimensional structure. The variable-temperature magnetic susceptibility of both compounds suggests that the metal ions and radicals are ferromagnetically coupled with J =2.78 and 1.11cm−1 for complexes 1 and 2, respectively. [Copyright &y& Elsevier]

Abstract: A new nitronyl nitroxide NIT2-bithph (1) and its manganese(II) compound [Mn(hfac)2(IMHBithph)]2·(NIT2-bithph)(C6H14) (2) (hfac=hexafluoroacetylacetonate; NIT2-bithph=4,4,5,5-tetramethyl-2-(bithiophenal-2-yl)imidazoline-1-oxyl-3-oxide; IMHBithph=1-hydroxy-2-bithiophenal-4,4,5,5-tetramethyl-4,5-dihydro- 1H-imidazole) have been synthesized and structurally characterized by X-ray diffraction methods. The units of compound 1 were connected as one-dimensional chain by the intermolecular hydrogen bonds which afford an intermolecular antiferromagnetic interaction between nitronyl nitroxide radicals within the chain (J =−1.89cm−1). Compound 2 resulting from the reaction of Mn(hfac)2·2H2O and NIT2-bithph is dinuclear and includes the reduced amidino-oxide form of NIT2-bithph, it is made up of three parts: a [Mn(hfac)2(IMHBithph)]2 dimer unit, an uncoordinated NIT2-bithph radical and a noncoordinated solvent molecule of hexane, the molecule of radical is hydrogen bonded to its reduced form. Two reduced IMHBithph ligands bridge the two manganese(II) ions through their amidino-oxide oxygen atoms resulting in a small intramolecular antiferromagnetic interaction between the manganese ions (J =−1.55cm−1). [Copyright &y& Elsevier]

Abstract: Lots of clustering algorithms have been developed, while most of them cannot process objects in hybrid numerical/nominal attribute space or with missing values. In most of them, the number of clusters should be manually determined and the clustering results are sensitive to the input order of the objects to be clustered. These limit applicability of the clustering and reduce the quality of clustering. To solve this problem, an improved clustering algorithm based on rough set (RS) and entropy theory was presented. It aims at avoiding the need to prespecify the number of clusters, and clustering in both numerical and nominal attribute space with the similarity introduced to replace the distance index. At the same time, the RS theory endows the algorithm with the function to deal with vagueness and uncertainty in data analysis. Shannon''s entropy was used to refine the clustering results by assigning relative weights to the set of attributes according to the mutual entropy values. A novel measure of clustering quality was also presented to evaluate the clusters. This algorithm was analyzed and applied later to cluster the data set of one industrial product. The experimental results confirm that performances of efficiency and clustering quality of this algorithm are improved. [Copyright &y& Elsevier]