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Metal organic frameworks (MOFs) have been well-known and extensively researched due to the high storage /good selectivity for gas molecules. Herein, the structures and electron paramagnetic resonance (EPR) spectra for dicopper paddle wheel MOF compound (Cu2(µ2-O2CCH3)4 with various gas molecule are theoretically investigated by density functional theory (DFT) calculations. The adsorption energies and isotherms (including pure gas molecules and the mixed ones) are calculated for the gas molecules interacting with the unsaturated Cu2(µ2-O2CCH3)4. Both quantities exhibit the roughly consistent orders (e.g. H2S > NH3 > CO2 > CO > H2O > N2 > NO > H2 for isotherms and H2S > NH3 > N2 > CO2 > NO > H2O > H2 > CO for adsorption energies), possibly suggesting that this material may act as a potential adsorbent of these gas molecules. The catalytic property of Cu2(µ2-O2CCH3)4 for oxidation of CO and NO into non-toxic molecules and splitting of H2O into H2 and O2 in the solvent condition are uniformly discussed. Simulation of Grand Canonical Monte Carlo (GCMC) in MS 8.0 and calculations in Langmuir model reveal that Cu2(µ2-O2CCH3)4 has good selectivity for CH4 in natural gas (CH4/CO2/N2) and SO2 in fog (SO2/NO/NO2/H2O/O2), which would exhibit potential environmentally friendly applications. [ABSTRACT FROM AUTHOR]

The spin Hamiltonian parameters (g factors, hyperfine structure constants and zero-field splittings D and E) and local structures for Mn2+ and Ni2+ in [Zn(en)3](NO3)2 single crystal are theoretically investigated from the perturbation calculations for trigonally distorted 3d5 and trigonally (or orthorhombically) distorted 3d8 cluster. The trigonal Mn2+ and Ni2+ centres are found to undergo the moderate angular variations Δβ of 4.5° and 5.2°, respectively, related to host Zn2+ site due to size mismatch. The orthorhombic Ni2+ centre shows the relative axial elongation ratio ρ (≈ 2.5%) and the relative perpendicular bond length variation ratio τ (≈0.2%). For Mn2+ centre, the contributions to g-shifts ΔgCT (or hyperfine structure constants ACT and zero-field splitting DCT) from charge-transfer (CT) mechanism are opposite in sign and five times (or 5% and 8%) in magnitude compared with those from crystal-field (CF) mechanism. For the trigonal Ni2+ centre, ΔgCT (or DCT) are the same (or opposite) in sign and 17% (or 2%) in magnitude related to those from CF mechanism. For the orthorhombic Ni2+ centre, ΔgCT and ECT (or DCT) are same (or opposite) in sign and 16% and 48% (or 442%) in magnitude with respect to those from the CF mechanism. The signs and magnitudes of the trigonal distortion angles δβ (≈ −0.3 and 0.4°) related to an ideal octahedron and the local angular variations Δβ related to the host bond angle are suitably illustrated by those of the axial distortion degree (ADD) and the angular variation degree (AVD) of the systems, respectively. [ABSTRACT FROM AUTHOR]

The electron paramagnetic resonance (EPR)gfactors and local structures for Ni3+in LiAlyCo1–yO2as the cathode materials for lithium-ion batteries are theoretically investigated at various Al concentrationsy(= 0.1, 0.5, 0.8 and 1.0). The [NiO6]9–clusters are subject to the tetragonal elongation distortions along theC4axis owing to the Jahn–Teller effect and the different degrees of distortions are characterised by the slightly increasing relative elongation ratioρ(and also crystal-field strength and covalency) withy. In pure LiAlO2(y = 1.0), the [NiO6]9–cluster exhibits the largestρ(≈1.4%) and an additional relative variation ratioτ(≈1.4%) of the planar bond lengths, responsible for the perpendicularganisotropyδg= (gx–gy). The number of impurity Ni3+centres increases from one aty = 0 and 1.0 to two aty = 0.1 and 0.8 and reaches the maximum four aty = 0.5, in accordance with the increasing degree of disorder of the systems. The distinct impurity centres for the sameymay be accompanied by the comparable energies of the ground and near excited states, similar to ‘resonant states’ with slightly different local elongation distortions and tetragonal level splittings. The present studies will be helpful to understand the relationships between local structures and performances of LiAlyCo1–yO2type cathode materials. [ABSTRACT FROM PUBLISHER]

Extranodal natural killer (NK)/T-cell lymphoma is an aggressive lymphoid tumor. Optimal treatment strategies have not yet been fully defined. To explore a more effective treatment, we conducted sequential chemoradiotherapy (SCRT) and evaluated the safety and efficacy. Seventy-eight patients (51 males, 27 females) were analyzed. The complete response (CR) rate was higher for patients in the SCRT group (90.9%) than in the radiotherapy group (77.8%;p = 0.124). The relapse rate (RR) and death rate (DR) were lower in the SCRT group (RR: 6.7% vs 33.3%,p < 0.001; DR: 15.2% vs. 55.6%,p < 0.001). Progression-free survival (PFS) and overall survival (OS) rates of 5 years after diagnosis were significantly higher for patients in the SCRT group (PFS: 89%; OS: 82%) than in the radiotherapy group (PFS: 49%,p <0.001; OS: 49%,p < 0.001). Treatment-related adverse events were more common in the SCRT group. However, the adverse events were controlled. [ABSTRACT FROM AUTHOR]

Bone is the primary site of skeletal metastasis in prostate cancer (PCa). Atelocollagen (ATE)-mediated siRNA delivery system can be used to silence endogenous genes involved in PCa metastatic tumor cell growth. However, we hope that the delivery system can target PCa cells to reduce damage to the bone tissue and improve the therapeutic effect. RNA aptamer (APT) A10-3.2 has been used as a ligand to target PCa cells that express prostate-specific membrane antigen (PSMA). APT was investigated as a PSMA-targeting ligand in the design of an ATE-based microRNA (miRNA; miR-15a and miR-16-1) vector to PCa bone metastasis. To observe the targeted delivery and transfection efficiency of ATE–APT in PSMA-overexpressing cells, luciferase activity and biodistribution of nanoparticles in Balb/c mice was analyzed. The anticancer effect of nanoparticlesin vivowas investigated using the survival times of human PCa bone metastasis mice model. Luciferase assays of pGL-3 expression against PC3 (PSMA−) and LNCaP (PSMA+) cells showed that the transfection efficiency of the synthesized DNA/ATE–APT complex was higher than that of the DNA/ATE complex. The anticancer efficacy of miRNA/ATE–APT was superior to those of other treatmentsin vivo. This PSMA-targeted system may prove useful in widening the therapeutic window and allow for selective killing of PCa cells in bone metastatic foci. [ABSTRACT FROM AUTHOR]

Two novel tetrahalogeno-4,4′-bi-1,2,4-triazoles, tetrachloro-4,4′-bi-1,2,4-triazole (1, TCBTr) and tetrabromo-4,4′-bi-1,2,4-triazole (2, TBBTr) were successfully synthesized through halogenation of 4,4′-bi-1,2,4-triazole (BTr) and structurally characterized by elemental analysis, IR,13C NMR and MS spectra. The single crystals of title compounds were cultivated and determined with X-ray diffraction, and the test results reveal that the aromatic π…π stacking interactions between molecules and the tetrahalogeno-4,4′-bi-1,2,4-triazoles with the two triazole rings being perpendicular are well observed in the crystal structure of (1) and (2). [ABSTRACT FROM PUBLISHER]

The article reviews the utility of anti-malarial drug chloroquine as a novel anti-tumor agent in cancer therapy. It analyzed several medical databases such as PubMed, ScienceDirect and ClinicalKey and notes that chloroquine executes its anti-tumor function through inhibition of autophagy. It concludes with the promising utility of chloroquine in cancer therapy and suggests conducting further studies on safety profile and the signs of clinical activity of chloroquine.

Marinacarbolines A–D are a series of marine β-carboline alkaloids isolated from actinomyceteMarinactinospora thermotoleransof the deep South China Sea with antiplasmodial activities. In inhibition assays ofin vitrogrowth ofPlasmodium falciparum, marinacarbolines exhibited antiplasmodial activity against drug-sensitive line 3D7 and drug-resistant line Dd2 ofP. falciparum. However, approaches for the synthesis of such useful compounds are very limited. In this work, we reported a simple, efficient, and versatile process to synthesize marinacarbolines A–D (1–4). On the basis of that, the antitumor activities of marinacarbolines in a structure-dependent manner were allowed to be unveiled. [ABSTRACT FROM AUTHOR]

Isomeric polyphenolic glycosides that possess regioisomericO-acylated saccharide residues can be found in many medicinal plants and their preparations as well as some synthetic intermediates. The need for a pure and sufficient quantity of compounds for nuclear magnetic resonance measurements calls for a microanalytical method for their rapid differ entiation. In the current investigation, an electrospray ionization–tandem mass spectrometric method was developed for rapid differentiation of two pairs of regioisomeric acylated monosaccharides, quercetin-3-O-(3″-O-galloyl)-α-L-rhamnopyranoside and quercetin-3-O-(2″-O-galloyl)-α-L-rhamnopyranoside as well as quercetin-3-O-(3″-O-galloyl)-β-D-glucopyranoside and quercetin-3-O-(2″-O-galloyl)-β-D-glucopyranoside; the mechanisms governing their similar or differential fragmentations are also discussed. The work may facilitate the structural determination of these regioisomers and their analogs in pure form or in complex matrix. [ABSTRACT FROM AUTHOR]

Two new steroidal saponins, dioscins E (1) and F (2), along with nine known steroidal saponins, were isolated from the biotransformation product of the rhizomes of Dioscorea nipponica using Aspergillus oryzae. The structures of new compounds were established as 25(R)-spirost-5-en-21β-methyl-3β-ol-3-O-α- l-rhamnopyranosyl-(1 → 4)-β-d-glucopyranoside (1) and (25R)-spirost-5-en-3β-ol-7-one 3-O-α- l-rhamnopyranosyl-(1 → 4)-β-d-glucopyranoside (2) by detailed spectroscopic analyses including 1D and 2D NMR spectral data (1H–1H COSY, HSQC, and HMBC) and MS spectrometry. [ABSTRACT FROM PUBLISHER]

Three series of sintenin derivatives (compounds 1-14) were designed and prepared and their antioxidative and neuroprotective effects were evaluated. The in vitro models of scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, chelating ferrous ions, inhibiting the rat brain homogenates lipid peroxidation, and protecting neurons damaged by hydrogen peroxide were employed for bioassays. It was found that sintenin derivatives 4 and 13 showed remarkable antioxidative and neuroprotective activities. [ABSTRACT FROM AUTHOR]