Cyclic [Cu-biRadical]2 Secondary Building Unit in 2p-3d and 2p-3d-4f Complexes: Crystal Structure and Magnetic Properties.

Employing the new nitronyl nitroxide biradical ligand biNIT-3Py-5-Ph (2-(5-phenyl-3-pyridyl)-bis(4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide)), a 16-spin Cu-radical complex, [Cu8(biNIT-3Py-5-Ph)4(hfac)16] 1, and three 2p-3d-4f chain complexes, {[Ln(hfac)3][Cu(hfac)2]2(biNIT-3Py-5-Ph)2}n (LnⅢ= Gd 2, Tb 3, Dy 4; hfac = hexafluoroacetylacetonate), have been prepared and characterized. X-ray crystallographic analysis revealed in all derivatives a common cyclic [Cu-biNIT]2 secondary building unit in which two bi-NIT-3Py-5-Ph biradical ligands and two CuII ions are associated via the pyridine N atoms and NO units. For complex 1, two such units assemble with four additional CuII ions to form a discrete complex involving 16 S = 1/2 spin centers. For complexes 2-4, the [Cu-biNIT]2 units are linked by LnIII ions via NO groups in a 1D coordination polymer. Magnetic studies show that the coordination of the aminoxyl groups with Cu or Ln ions results in behaviors combining ferromagnetic and antiferromagnetic interactions. No slow magnetic relaxation behavior was observed for Tb and Dy derivatives.

Supramolecular heptanuclear Ln-Cu complexes involving nitronyl nitroxide biradicals: structure and magnetic behavior.

Four novel heptanuclear Ln-Cu complexes with the formula [Ln2Cu(hfac)8(NITPhTzbis)2][LnCu(hfac)5(NITPhTzbis)]2 (LnCu = YCu 1, TbCu 2, DyCu 3 and HoCu 4; hfac = hexafluoroacetylacetonate) were successfully constructed by employing the triazole functionalized nitronyl nitroxide biradical ligand NITPh-Tzbis (NITPh-Tzbis = 5-(1,2,4-triazolyl)-1,3-bis(1'-oxyl-3'-oxido-4',4',5',5'-tetramethyl-4,5-hydro-1H-imidazol-2-yl)benzene). These hetero-tri-spin complexes are composed of two biradical-bridged dinuclear [(LnCu(hfac)5(NITPhTzbis)] units and one trinuclear [Ln2Cu(hfac)8(NITPhTzbis)2] unit which form a heptanuclear supramolecular structure through π-π interactions. Magnetic susceptibility investigations indicate that ferromagnetic exchange interactions dominate at low temperature for this supramolecular system which can be attributed to the Ln-nitroxide exchange and intramolecular NIT⋯NIT coupling mediated by the m-phenylene moiety. The DyCu derivative was found to exhibit a slow magnetic relaxation behavior.

Rational Design of Dot-on-Rod Nano-Heterostructure for Photocatalytic CO2 Reduction: Pivotal Role of Hole Transfer and Utilization.

Inspired by green plants, artificial photosynthesis has become one of the most attractive approaches toward carbon dioxide (CO2 ) valorization. Semiconductor quantum dots (QDs) or dot-in-rod (DIR) nano-heterostructures have gained substantial research interest in multielectron photoredox reactions. However, fast electron-hole recombination or sluggish hole transfer and utilization remains unsatisfactory for their potential applications. Here, the first application of a well-designed ZnSe/CdS dot-on-rods (DORs) nano-heterostructure for efficient and selective CO2 photoreduction with H2 O as an electron donor is presented. In-depth spectroscopic studies reveal that surface-anchored ZnSe QDs not only assist ultrafast (≈2 ps) electron and hole separation, but also promote interfacial hole transfer participating in oxidative half-reactions. Surface photovoltage (SPV) spectroscopy provides a direct image of spatially separated electrons in CdS and holes in ZnSe. Therefore, ZnSe/CdS DORs photocatalyze CO2 to CO with a rate of ≈11.3 µmol g-1 h-1 and ≥85% selectivity, much higher than that of ZnSe/CdS DIRs or pristine CdS nanorods under identical conditions. Obviously, favored energy-level alignment and unique morphology balance the utilization of electrons and holes in this nano-heterostructure, thus enhancing the performance of artificial photosynthetic solar-to-chemical conversion.

Elevation of Serum PARK7 and IL-8 Levels Is Associated With Acute Lung Injury in Patients With Severe Sepsis/Septic Shock.

OBJECTIVE: Methods containing only clinical information fail to meet the needs of prediction of acute lung injury (ALI) because of the relatively low positive predictive value. This study aimed to investigate the feasibility of using biomarkers as predictors of ALI in populations with severe sepsis/septic shock and to explore difference among biomarkers after adjustment for potential confounders. METHODS: Serum specimens were collected from patients with severe sepsis/septic shock (n = 172) presented to the emergency department. Patients should be ruled out from the study if they were already suffering from ALI or if they deteriorated into ALI within 6 hours after specimen collection. The development of ALI of the remaining patients was tracked. RESULTS: Of all patients with severe sepsis/septic shock who encountered ALI more than 6 hours succeeding to specimen collection, 19 deteriorated into ALI. Elevation in serum interleukin 8 (IL-8) and Parkinson disease 7 (PARK7) levels had significant connection with higher risk of developing ALI (P = .006; P = .0001). Sepsis treatment and vasopressor application led to a robust connection between PARK7 and succeeding ALI development. Patients who deteriorated into ALI were distinguished accurately from patients who avoided ALI using PARK7 or Lung Injury Prediction Score (LIPS; area under the receiver operating characteristic curve [AUROC], 0.73 and 0.72 for each). Combination of PARK7 and LIPS ameliorated AUROC to 0.86 (vs 0.73, P = .05). On the contrary, serum soluble receptor for advanced glycation end products and von Willebrand factor made no contribution to the prediction of ALI development. CONCLUSIONS: Patients with PARK7 or IL-8 levels above normal are more vulnerable to ALI. Patients vulnerable to ALI can be distinguished with the combination of serum biomarkers and clinical prediction scores. In addition, the early rise in PARK7 emphasizes the importance of endothelial injury in the early pathogenesis of ALI.

Sustained increase in angiopoietin-2, heparin-binding protein, and procalcitonin is associated with severe sepsis.

PURPOSE: The identification of infection at its early stage in vulnerable patients is challenging. This study aimed to investigate potential biomarkers to distinguish patients progressing to severe sepsis from those with uncomplicated sepsis. MATERIALS AND METHODS: Serum samples were collected from sepsis patients admitted to the emergency department. The mRNA and protein levels of angiopoietin-2 (Ang-2), interleukin-10 (IL-10), heparin-binding protein (HBP), procalcitonin (PCT), adrenomedullin (ADM), and interleukin-6 (IL-6) were evaluated. RESULTS: Compared to those of healthy individuals (n = 47), mRNA levels of ANG2, IL10, HBP, PCT, and ADM were increased in patients who eventually developed sepsis. ANG2 was the only gene whose expression was significantly increased in patients developing severe sepsis than in those with uncomplicated sepsis. Serum levels of Ang-2, IL-10, HBP, PCT, and IL-6 were also increased in sepsis patients, but only Ang-2, HBP, and PCT were elevated in the serum of patients developing severe septic shock than in those with uncomplicated sepsis. Serum levels of Ang-2, HBP, and PCT were closely associated with the sequential organ failure assessment (SOFA) score of the patients. CONCLUSIONS: These findings indicated that sustained elevation of Ang-2, HBP, and PCT were associated with severe infection in critically ill patients.

Protective Effects of Chymostatin on Paraquat-Induced Acute Lung Injury in Mice.

This study aims to evaluate the role of chymostatin in paraquat-induced acute lung injury. Institute of Cancer Research mice were randomly distributed into the NS, DMSO, chymostatin, paraquat or chymostatin treatment groups. Six mice from each group were intraperitoneally injected with chloral hydrate at 0, 1, 2, 4, 8, 12, 24 and 48 h after treatment administration. Blood samples were collected through cardiac puncture. Lung tissues were stained with haematoxylin and eosin for the observation of lung histology. The degree of pulmonary oedema was determined on the basis of lung wet-to-dry ratio (W/D). The serum activity of cathepsin G was determined through substrate fluorescence assay. The serum levels of endothelial cell-specific molecule-1 (endocan), tumour necrosis factor-a (TNF-a), interleukin-1ß (IL-1ß), IL-6 and high-mobility group box protein 1 (HMGB1) were determined through enzyme-linked immunosorbent assay. The expression levels of endocan and nuclear NF-κBp65 in the lung were quantified through Western blot. Chymostatin alleviated the pathological changes associated with acute alveolitis in mice; decreased the lung W/D ratio, the activity of cathepsin G and the serum concentrations of TNF-a, IL-1ß, IL-6 and HMGB1; and increased the serum concentration of endocan. Western blot results revealed that chymostatin up-regulated endocan expression and down-regulated nuclear NF-κBp65 expression in the lung. Chymostatin reversed the inflammatory effects of paraquat-induced lung injury by inhibiting cathepsin G activity to up-regulate endocan expression and indirectly inhibit NF-κBp65 activity.

Interleukin-17A Plays the Same Role on Mice Acute Lung Injury Respectively Induced by Lipopolysaccharide and Paraquat.

Interleukin-17A (IL-17A) is involved in multiple inflammatory diseases. Our study was to investigate the role of IL-17A on acute lung injury (ALI) respectively induced by lipopolysaccharide (LPS) and paraquat (PQ) on mice. We built ALI mouse models respectively by single intraperitoneal (i.p.) injection with LPS or single gavage with PQ liquid. Two hours after the models were established, a dosage of neutralizing antibody was used to blockade IL-17A by i.p. injection. At 8, 24, and 48 h, the lung wet-to-dry ratio (W/D) was calculated and total protein in bronchoalveolar lavage fluid (BALF) was measured; hematoxylin-eosin staining was used to observe lung tissue pathological changes; inflammatory cells in BALF were recorded with a hemocytometer; cytokines were measured with enzyme-linked immunosorbent assay kits; immunohistochemistry examined the expression of IL-17A and activation of nuclear factor-κB p65 (NF-κB p65); and qPCR determined the expression of IL-17A mRNA. After being administered with LPS or PQ, all mice presented ALI pathological change; expression of IL-17A increased significantly. When blocking IL-17A with antibody, lung injury in both LPS- and PQ-administrated mice was attenuated. All the above tests decreased. Compared with those in PQ mice, IL-17A levels in LPS mice were higher. IL-17A involves the ALI induced by LPS or PQ and promotes the pathological process by activating NF-κB P65 and recruiting neutrophils, which enlarges the cascade effect of inflammation and injures lung tissues. And when blockading IL-17A with antibody, the ALI is alleviated. The reaction of IL-17A in the ALI induced by LPS is stronger than that by PQ.

Microchip-based small, dense low-density lipoproteins assay for coronary heart disease risk assessment.

Small, dense low-density lipoprotein (sdLDL) has been accepted as an emerging cardiovascular risk factor, and there has been an increasing interest in analytical methods for sdLDL profiling for diagnosis. Serum sdLDL may be measured by different laboratory techniques, but all these methods are laborious, time-consuming, and costly. Recently, we have demonstrated that a low-temperature bonding of quartz microfluidic chips for serum lipoproteins analysis (Zhuang, G., Jin, Q., Liu, J., Cong, H. et al., Biomed. Microdevices 2006, 8, 255-261). In contrast to this previous study, we chose SDS as anionic surfactant to modify both lipoproteins and the channel surface to minimize lipoprotein adsorption and improve the resolution of lipoprotein separation. Two major LDL subclass patterns including large, buoyant LDL (lLDL), sdLDL, and high-density lipoprotein (HDL) were effectively separated with high reproducibility. RSD values of the migration time (min) and peak areas of standard LDL and HDL were 6.28, 4.02, 5.02, and 2.5%, respectively. Serum lipoproteins of 15 healthy subjects and 15 patients with coronary heart disease (CHD) were separated by microchip CE. No peaks of sdLDL were detected in serum samples of healthy subjects while sdLDL fractional peaks were observed in patients' entire serum samples. These results suggested that the microchip-based sdLDLs assay was a simple, rapid, and highly efficient technique and significantly improved the analysis of CHD risk factors.

[Temperature-dependence emission properties of Eu(3+)-doped in LiNbO3 single crystal].

The temperature-dependence emission spectra of lower and upper part of Eu(3+) -doped LiNbO3 crystals from 77 to 600 K were investigated under the excitation of a 488 nm light. The results show that, for upper part of crystal, the fluorescence intensity of Eu3+ ions increases with the temperature increase, however, for lower part, the intensity first increases with the temperature increase, and then decreases obviously with temperature increase. The variations of fluorescence intensity for lower and upper part of crystals are explained. The emission intensity of Eu3+ ions in LN is the total effect of thermally excited emission, phonon-assistant absorption and temperature-quenching effect.

[Preparation and room temperature emission of nanocrystalline ZnO: Er3+].

The nanocrystalline ZnO:RE powders with room temperature sharp photoluminescence were prepared successfully by chemical precipitation method in the present work. This is a great progress in the study of rare earth doped ZnO. For the ZnO:Er3+ obtained in the present paper, the room temperature sharp characteristic emissions from the trivalent rare earth Er3+, including upconversion and near infrared emission, and the energy transfer between the nanocrystalline ZnO host and the dopants were observed.

Study on the Extracting Method and Producing Conditions of Phyllosticta commelimecola Toxin / 微生物学通报

The crude toxin was extracted from hypha and culture solution of Phyllosticta commelimecola through three different polarity solvent: benzinum, puncificatum ethyl acetate and chloroform. The result indicated that the toxin secreted by Phyllosticta commelimecola not only was in hypha but also in culture solution and the extracting effect of ethyl acetate was the best. The soybean median and PSK media can be respectively used as solid and liquid culture media to produce toxin and grow mycelium. The optimal cultural conditions for producing toxin were temperature 32℃,cultured period 14d, cultured ways shaking of 150r/min.