Phase selectivity and tunable photophysical nature of rare earth metal-organic frameworks of EuxY1-x-PTC (H3PTC = 2,4,6-pyridine tricarboxylic acid; x = 0-1).

Two rare earth metal-organic frameworks (MOFs), [Y2(PTC)2(H2O)2]·3H2O (Y-PTC) and [Eu2(PTC)2(H2O)5]·H2O (Eu-PTC) together with the solid solutions [Eu2xY2(1-x)(PTC)2(H2O)5]·H2O (EuxY1-x-PTC, x = 0.013-0.82), were synthesized hydrothermally, and characterized by microanalysis, IR spectroscopy, TG, powder, and single crystal X-ray diffraction techniques. Eu-PTC and Y-PTC showed different crystal structures; however, all solid solutions were isomorphic to Eu-PTC even at x = 0.013, leading to the IR spectra and TG plots of the solid solutions to be similar to those of Eu-PTC but distinct from those of Y-PTC. DFT calculations for the crystal lattice energy demonstrated that the procedure for the crystallizing nucleation of Eu-PTC occurred prior to that of Y-PTC in the reaction solution, leading to the all solid solutions being isomorphic to Eu-PTC. The solid emission spectra at ambient condition showed that Y-PTC emitted ligand-based phosphorescence at 433 nm with a quantum yield (QY) of 27.02%, while Eu-PTC and EuxY1-x-PTC (x = 0.013-0.82) emitted the characteristic luminescence of Eu3+ ions, and most solid solutions showed higher QYs than Eu-PTC; in particular, the QY of Eu0.195Y0.805-PTC was up to 29.48%, i.e., increased by 10% regarding Eu-PTC (19.86%). Interestingly, solid solutions with x = 0.013-0.395 showed excitation-wavelength-dependent luminescence, and such type of luminescence MOFs have promising applications including the areas of precise temperature, gas sensing and information encryption or anti-counterfeiting materials.

Crystal Structures, Photoluminescence, and Magnetism of Two Novel Transition-Metal Complex Cocrystals with Three-Dimensional H-Bonding Organic Framework or Alternating Noncovalent Anionic and Cationic Layers.

Cocrystallization may alter material physicochemical properties; thus, the strategy of forming a cocrystal is generally used to improve the material performance for practical applications. In this study, two transition-metal complex cocrystals [Zn(bpy)3]H0.5BDC·H1.5BDC·0.5bpy·3H2O (1) and [Cu2(BDC)(bpy)4]BDC·bpy·2H2O (2) have been achieved using a hydrothermal reaction, where bpy and H2BDC represent 2,2'-bipyridine and benzene-1,3-dicarboxylic acid, respectively. Cocrystals were characterized by microanalysis, infrared spectroscopy, and UV-visible spectroscopy. Cocrystal 1 contains five components and crystallizes in a monoclinic space group P21/n. The H0.5BDC1.5-, H1.5BDC0.5-, and H2O molecules construct three-dimensional H-bonding organic framework; the [Zn(bpy)3]2+ coordination cations and uncoordinated bpy molecules reside in channels, where two coordinated bpy ligands in [Zn(bpy)3]2+ and one uncoordinated bpy adopt sandwich-type alignment via π···π stacking interactions. Cocrystal 2 with four components crystallizes in a triclinic space group P-1 to form alternating layers; the binuclear [Cu2(bpy)4(BDC)]2+ cations and uncoordinated bpy molecules build the cationic layers, and the BDC2- species with disordered lattice water molecules form the anionic layers. Cocrystal 1 shows intense photoluminescence at an ambient condition with a quantum yield of 14.96% and decay time of 0.48 ns, attributed to the π* → π electron transition within phenyl/pyridyl rings, and 2 exhibits magnetic behavior of an almost isolated spin system with rather weak antiferromagnetic coupling in the [Cu2(bpy)4(BDC)]2+ cation.

Stereochemically Active and Inactive Lone Pairs in Two Room-Temperature Phosphorescence Coordination Polymers of Pb2+ with Different Tricarboxylic Acids.

Two new Pb2+-based coordination polymers (CPs), [Pb2(HBTC)2(DMF)] (1) and [Pb(HPTC)] (2), have been synthesized under solvothermal condition; herein, H3BTC and H3PTC represent 1,3,5-benzenetricarboxylic acid and 2,4,6-pyridine tricarboxylic acid, respectively. Both 1 and 2 were characterized by microanalysis, infrared spectra (IR), thermal gravimetric analyses (TGA), and powder X-ray diffraction (PXRD) techniques. Single-crystal structural analysis indicates that 1 and 2 show different coordination sphere around Pb2+ ions and distinct coordination frameworks. The I1O2 type three-dimensional (3D) nonporous metal-organic framework forms in 1, where the Pb2+ ion shows holo-directed coordination geometry, while the I0O2 type two-dimensional (2D) coordination polymeric layered structure forms in 2, where Pb2+ ion shows a hemidirected coordination sphere and the 6s2 lone electron pair in Pb2+ ion is stereochemically active. The two CPs emit intense and long-lasting greenish phosphorescence in air at room temperature, with absolute quantum yields of 1.2% for 1 and 4.7% for 2 and decay lifetimes of 0.73 ms for 1 and 1.52 ms for 2.

An open-label, randomized and multi-center clinical trial to evaluate the efficacy of Silibinin in preventing drug-induced liver injury.

UNLABELLED: To assess the clinical efficacy and safety of Silibinin in preventing drug-induced liver injury (DILI) in the general population (high-risk patients with non-drug induced liver injury). METHOD: A prospective, multi-center, randomized, open-label and controlled trial was conducted with 568 patients undergoing primary treatment of pulmonary tuberculosis. The study included 277 patients in experimental group and 291 patients in control group. The patients in the two group were treated with conventional 2HREZ (S)/4HR for tuberculosis (TB), and additional Silibinin capsules (oral administration of 70 mg/time, 3 times/day for 8 weeks in experimental group. Outcomes of liver function, interruption of anti-TB treatment and therapeutic results, as well as adverse reactions were observed and analyzed. RESULTS: At 2, 4 and 8 weeks of treatment, the incidences of liver injury in experimental group were 3.97%, 1.44% and 2.17%, respectively; the incidences in control group were 4.12%, 4.12% and 2.41%, respectively. Statistical analysis showed that there was no difference in the incidence between the two groups at each treatment period (P>0.05). At 8 weeks, the numbers of patients diagnosed of DILI were 18 (7.22%) and 27 (9.28%) in experimental and control groups, respectively (P>0.05). 34.30% and 27.49% of the patients in experimental and control groups had transient abnormal liver function or symptoms, respectively; similar percentages (3.25% and 6.19%) of the patients in two groups have liver function injury and symptoms, and were suspended for anti-TB treatment (P>0.05). The incidence of anorexia and nausea symptoms was lower in experimental group than in control group, and the differences were significant at 4 and 8 weeks (P<0.05). 8 weeks after the treatment, 98.30% of the sputum smear culture were negative in experimental group, which was significantly higher (P<0.01) than that in control group (92.98%). CONCLUSION: Preventive hepatoprotective therapy in the general population may reduce drug discontinuation rate, improve patient's compliance and outcomes of anti-TB treatment.

Hg2+-selective ratiometric and "off-on" chemosensor based on the azadiene-pyrene derivative.

A new pyrene-based derivative bearing an azadiene group was synthesized as a ratiometric chemosensor for Hg(2+) in aqueous acetonitrile solution. The "off-on" type signaling behavior of the fluoroionophore is due to the metal ion induced conformational changes from the weak pyrene monomer emissions to strong pyrene excimer emission.

[The clinical significance of serum tuberculosis specific antigen antibody in the diagnosis of tuberculosis].

OBJECTIVE: To evaluate the significance of serum tuberculosis specific antigen (TB-SA) antibody detection in the diagnosis of tuberculosis. METHODS: TB-SA antibody in the serum samples from 829 cases of tuberculosis, 278 patients with non-tuberculosis lung diseases and 125 healthy volunteers were detected using enzyme-linked immunosorbent assay (ELISA). Tuberculosis was confirmed by clinical, bacteriology, X-ray examination and pathology studies. RESULTS: The sensitivity of TB-SA antibody in diagnosis of bacteriologically positive and negative pulmonary tuberculosis and extrapulmonary tuberculosis was 75.1% (272/362), 68.9% (226/328) and 71.2% (99/139), respectively; the combined sensitivity was 72.0% (597/829), and the specificity 82.1% (331/403). The relationship between the OD(405) of TB-SA antibody and PPD positivity showed no linear relationship, suggesting that BCG vaccination did not affect the value of serum TB-SA antibody. CONCLUSION: The results suggest that measurement of serum TB-SA is a relatively sensitive and specific method for the diagnosis and differential diagnosis of tuberculosis.