Lanthanide nitrato complexes bridged by the bis-tridentate ligand 2,3,5,6-tetra(2-pyridyl)pyrazine: Syntheses, crystal structures, Hirshfeld surface analyses, luminescence properties, DFT calculations, and magnetic behavior.

Six dinuclear lanthanide(III) nitrato complexes [Ln(NO3)3(H2O)]2(µ-tppz) (where tppz = 2,3,5,6-tetra(2-pyridyl) pyrazine and Ln(III) = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), and Dy (6)) with bis-tridentate N-heterocyclic 2,3,5,6-tetra(2-pyridyl)pyrazine as bridging ligand have been solvothermally synthesized and characterized via elemental analysis, infrared spectroscopy, thermogravimetric analysis, single-crystal X-ray diffraction, and powder X-ray diffraction. The 3-D Hirshfeld surface and 2-D fingerprint plots show that the main interactions in 1-6 are the O⋯H/H⋯O intermolecular interactions with relative contributions of about 62%. Although the poor lanthanide(III)-centered luminescence properties clearly point to the efficiency of nonradiative quenching processes (presence of water molecules in the coordination sphere of the lanthanide(III) ions), the ligand tppz is better suited to sensitize the lanthanide(III)'s emissions of EuIII and NdIII than SmIII, TbIII, and DyIII. Finally, the magnetic data of DyIII comple×6 reveals antiferromagnetic coupling between DyIII ions.

Cancer increases risk of in-hospital death from COVID-19 in persons <65 years and those not in complete remission.

The impact of cancer on outcome of persons with coronavirus disease 2019 (COVID-19) after infection with acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is controversial. We studied 1859 subjects with COVID-19 from seven centers in Wuhan, China, 65 of whom had cancer. We found having cancer was an independent risk factor for in-hospital death from COVID-19 in persons <65 years (hazard ratio [HR] = 2.45, 95% confidence interval [CI], 1.04, 5.76; P = 0.041) but not in those ≥65 years (HR = 1.12 [0.56, 2.24]; P = 0.740). It was also more common in those not in complete remission. Risks of in-hospital death were similar in subjects with solid cancers and those with hematological cancers. These data may help predict outcomes of persons with cancer and COVID-19.

Risk factors for death in 1859 subjects with COVID-19.

We studied 1859 subjects with confirmed COVID-19 from seven centers in Wuhan 1651 of whom recovered and 208 died. We interrogated diverse covariates for correlations with risk of death from COVID-19. In multi-variable Cox regression analyses increased hazards of in-hospital death were associated with several admission covariates: (1) older age (HR = 1.04; 95% Confidence Interval [CI], 1.03, 1.06 per year increase; P < 0.001); (2) smoking (HR = 1.84 [1.17, 2.92]; P = 0.009); (3) admission temperature per °C increase (HR = 1.32 [1.07, 1.64]; P = 0.009); (4) Log10 neutrophil-to-lymphocyte ratio (NLR; HR = 3.30 [2.10, 5.19]; P < 0.001); (5) platelets per 10 E + 9/L decrease (HR = 0.996 [0.994, 0.998]; P = 0.001); (6) activated partial thromboplastin (aPTT) per second increase (HR = 1.04 [1.02, 1.05]; P < 0.001); (7) Log10 D-dimer per mg/l increase (HR = 3.00 [2.17, 4.16]; P < 0.001); and (8) Log10 serum creatinine per µmol/L increase (HR = 4.55 [2.72, 7.62]; P < 0.001). In piecewise linear regression analyses Log10NLR the interval from ≥0.4 to ≤1.0 was significantly associated with an increased risk of death. Our data identify covariates associated with risk of in hospital death in persons with COVID-19.

A new family of sunlight-driven bifunctional photocatalysts based on TiO2 nanoribbon frameworks and bismuth oxohalide nanoplates.

By taking advantage of the structural affinity between bismuth oxohalide and TiO2, we successfully prepare a family of hybrid frameworks via the designated growth of bismuth oxohalide nanoplates on TiO2 nanoribbons, and propose them as sunlight-driven bifunctional photocatalysts for all-weather removal of pollutants. The structural variability of bismuth oxohalide allows the optical absorption of the hybrid framework to be monotonically tuneable across the visible spectrum. Meanwhile, the hybridization greatly increases the surface roughness of the frameworks and enables the frameworks to harvest more photons to participate in photocatalytic reactions. Furthermore, the hybridization establishes two potential gradients to promote the separation of photo-induced electron-hole pairs: the internal electrical field perpendicular to the wide surfaces of bismuth oxohalide nanoplates and across the semiconductor-semiconductor heterojunction. Owing to the synergetic effects of the permeable mesoporous architecture, the intense visible light absorption, and the efficient charge separation, the hybrid frameworks are capable of all-weather removal of pollutants: they utilize the inter-ribbon pores to gather pollutants in the dark (behaving as collectors) and they rapidly degrade the pollutants in the day (behaving as photocatalysts). In particular, the BiOBr@TiO2 framework exhibits very impressive sunlight-driven photocatalytic activity, which is much higher than commercially available P25 TiO2 under the same conditions.

Deterministic growth of AgTCNQ and CuTCNQ nanowires on large-area reduced graphene oxide films for flexible optoelectronics.

We describe a synchronous reduction and assembly procedure to directly produce large-area reduced graphene oxide (rGO) films sandwiched by a high density of metal nanoparticles (silver and copper). Further, by using the sandwiched metal NPs as sources, networks consisting of AgTCNQ and CuTCNQ nanowires were deterministically grown from the rGO films, forming structurally and functionally integrated rGO/metal-TCNQ hybrid films with outstanding flexibility, bending endurance, and electrical stability. Interestingly, due to the p-type nature of the rGO film and the n-type nature of the metal-TCNQ NWs, the hybrid films are essentially thin-film p-n junctions which are useful in ubiquitous electronics and optoelectronics. Measurements of the optoelectronic properties demonstrate that the rGO/metal-TCNQ hybrid films exhibit substantial photoconductivity and highly reproducible photoswitching behaviours. The present approach may open the door to the versatile and deterministic integration of functional nanostructures into flexible conducting substrates and provide an important step towards producing low-cost and high-performance soft electronic and optoelectronic devices.

Resonance light scattering study on the interaction between quinidine sulfate and congo red and its analytical application.

The interaction between quinidine sulfate (QDS) and congo red (CR) was studied using resonance light scattering (RLS) technique, ultraviolet-visual spectrophotometry and fluorimetry. In weak acidic medium, QDS reacts with CR to form a supermolecular complex which results in the enhanced RLS intensity. Some important interacting parameters, such as the solution acidity and CR concentration, salt effect and addition order of the reagents, were investigated and optimized. Under the optimum conditions, it was found that the enhanced RLS intensity was in proportion to the concentration of QDS in the range 0.2-8.4 microg mL(-1). The corresponding detection limit was 12.0 ng mL(-1). The results showed that this new method enabled simple, sensitive and rapid determination of QDS and was used for the determination of QDS in urine and simulated huamn serum samples.

SUCI02 inhibits the erbB-2 tyrosine kinase receptor signaling pathway and arrests the cell cycle in G1 phase in breast cancer cells.

The erbB-2 gene encodes tyrosine kinase receptor p185(neu). Overexpression of erbB-2 plays a key role in tumorigenesis and the progression of tumors such as breast cancer and ovarian cancer. Our investigation suggests that the anti-inflammatory agent N-(4-ethoxyphenol)-2-hydroxy-acid amide (SUCI02) reversibly represses tyrosine phosphorylation of erbB-2 in a dose-dependent manner, with half maximal inhibition occurring at a concentration of 21.05 micromol/L without reduced erbB-2 receptor expression. Activation of mitogen-activated protein kinase and protein kinase B, downstream molecules of the erbB-2-mediated signal transduction pathway, was inhibited following exposure to SUCI02. In contrast, tyrosine phosphorylation of epidermal growth factor receptor (EGFR) was relatively unaffected by SUCI02. Proliferation of erbB-2-overexpressing BT474 cells was inhibited to a greater extent than proliferation of EGFR-overexpressing A431 cells following exposure to SUCI02. SUCI02 induced cell cycle arrest in G(1) phase with upregulation of p27 and downregulation of pRb phosphorylation. Systemic administration of SUCI02 in nude mice resulted in inhibition of erbB-2 tyrosine kinase phosphorylation of subcutaneous human breast cancer BT474 xenografts. We conclude that SUCI02 inhibits erbB-2 tyrosine kinase phosphorylation in vitro and in vivo, shuts down the erbB-2 downstream pathway and induces cell cycle arrest in G(1) phase. These results suggest that SUCI02 is a potential novel anticancer agent that deserves further investigation. (Cancer Sci 2006; 97: 84-89).

[SUCI02 inhibits HER-2/neu receptor tyrosine kinase phosphorylation and growth of HER-2/neu-overexpressing breast cancer cells].

BACKGROUND & OBJECTIVE: Overexpression of HER-2/neu receptor plays a key role in tumorigenesis,progression,prognosis and chemosensitivity of tumors. We found that SUCI02[N-(4-ethoyphenol)-2-hydroxy- acid amide] could inhibit HER2/neu phosphorylation through comprehensive screening. The aim of this study was to examine the effect of SUCI02 on HER-2/neu-overexpressing cancer cell growth. METHODS: Western blot analysis and immunoprecipitation was used to examine the changes of HER-2/neu receptor tyrosine kinase phosphorylation and protein level. MTT assay was employed to determine the growth inhibition of SUCI02 on the tumor cells. RESULTS: SUCI02 reversibly inhibited tyrosine phosphorylation of HER-2/neu in a dose-dependent manner with half maximal inhibition at a concentration of 4.34 microg/ml without reduced HER-2/neu receptor protein expression. Activation of MAPK and AKT, which were downstream molecules of HER-2/neu-mediated signal transduction pathway, was inhibited after being exposure to SUCI02. In contrast, tyrosine phosphorylation of EGFR was relatively unaffected at the concentrations of SUCI02 up to 40 microg/ml. SUCI02 inhibited cell proliferation of HER-2/neu- overexpressing MDA-MB-453m1 more potent than that of EGFR-overexpressing MDA-MB-468.Their IC(50) values were 1.33 microg/ml and 11.3 microg/ml,respectively. CONCLUSION: SUCI02 can inhibit tyrosine phosphorylation of HER-2/neu receptor,cell proliferation of HER-2/neu-overexpressing breast cancer cells preferentially and shut down downstream HER-2/neu signal transduction.