DNA damage induced by m-phenylenediamine and its derivative in the presence of copper ion

We have previously reported that long-term priming of human polymorphonuclear neutrophilic granulocytes (PMN) with interferon-gamma (IFN-gamma) increased the fMLP-stimulated calcium influx. We now show that also after short-term incubation with IFN-gamma, PMN calcium metabolism is modulated. Single adherent cells in three different calcium-containing buffers (high, normal, and low [Ca2+]) were stimulated with the bacterial peptide fMLP or the Ca-ATPase inhibitor thapsigargin (Tg) after about 5 min preincubation with IFN-gamma. The results of this protocol indicated that IFN-gamma increases both calcium influx and calcium sequestration. Store dependent Ca2+ influx, directly measured on readdition of calcium to Tg-treated cells incubated in EGTA buffer, was significantly enhanced in IFN-gamma-treated cells. This effect of IFN-gamma was enhanced by the tyrosine kinase inhibitor herbimycin A. Strikingly, in low extracellular calcium concentrations, IFN-gamma induced calcium transients in 20%-60% of the cells. The proportion of PMN responding with Ca2+ transients increased with decreasing extracellular calcium concentration. Average lagtime from addition of IFN-gamma to a response that could be measured was 7.3 sec, and average increase in [Ca2+] above the basal level was 790 nM. These IFN-gamma-induced transients could not be depressed by herbimycin A. Thus, IFN-gamma can increase capacitative calcium influx, induce calcium transients, and possibly affect calcium sequestration in human PMN.     

Solvent-deficient synthesis of cerium oxide: Characterization and kinetics

The reaction mechanism and kinetics of CeO₂ synthesis using a solvent-deficient method are investigated by simultaneous thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The decomposition process of the cerium(III) nitrate hexahydrate and ammonium bicarbonate precursor mixture with four observed stages is monitored using TGA/DSC measurements in a nonisothermal regime with heating rates of 5, 10, 15 and 20?°C min^?1. The proposed mechanism indicates a complex synthesis with several parallel reactions, some of which occur at room temperature. A detailed kinetic analysis is performed using isoconversional (expanded Friedman, modified Coats-Redfern and Kissinger) and model fitting (N^th order and nucleation and growth models) methods. The first three stages are best described by the N^th order model with activation energy values of 21, 53 and 90?kJ?mol^?1. The last stage, during which ammonium nitrate decomposition occurs, is best fit by the nucleation and growth model and has an activation energy of 129?kJ?mol^?1. The proposed mechanism, supported by the kinetic analysis in our study, indicates that CeO₂ has already formed before the reaction reaches 200?°C. The average crystallite size of CeO₂ synthesized at 300?°C, which was calculated from the XRD measurements and observed in the SEM and TEM data, is between 10 and 20?nm.     

How can Correlation ρ13 Deviate,when ρ12 and ρ23 are Given?

Behaviormetrika - Suppose that the correlations ρ12=ρ23=0.9 are given. Then how can ρ13 deviate from 0.9? The answer is 0.62≦ p13≦1, as Tables 1 and 2 in this note show....     

Observation of the solid-state formation of a TTF–CA complex by terahertz spectroscopy

The solid-state synthesis of a tetrathiafulvalene–chloranil (TTF–CA) complex was demonstrated, and progress in the formation of the complex was monitored using a GaP Raman terahertz (THz) spectrometer. Clear transitions in the THz absorption spectra indicated that the mixture of TTF and CA became the black phase TTF–CA complex. The results of X-ray diffraction, Raman scattering, and FTIR spectra are presented as supporting evidence.     

Oxidative Stress and Its Significant Roles in Neurodegenerative Diseases and Cancer

Reactive oxygen and nitrogen species have been implicated in diverse pathophysiological conditions, including inflammation, neurodegenerative diseases and cancer. Accumulating evidence indicates that oxidative damage to biomolecules including lipids, proteins and DNA, contributes to these diseases. Previous studies suggest roles of lipid peroxidation and oxysterols in the development of neurodegenerative diseases and inflammation-related cancer. Our recent studies identifying and characterizing carbonylated proteins reveal oxidative damage to heat shock proteins in neurodegenerative disease models and inflammation-related cancer, suggesting dysfunction in their antioxidative properties. In neurodegenerative diseases, DNA damage may not only play a role in the induction of apoptosis, but also may inhibit cellular division via telomere shortening. Immunohistochemical analyses showed co-localization of oxidative/nitrative DNA lesions and stemness markers in the cells of inflammation-related cancers. Here, we review oxidative stress and its significant roles in neurodegenerative diseases and cancer.     

CD147-Cyclophilin a Interactions Promote Proliferation and Survival of Cutaneous T-Cell Lymphoma

CD147, a transmembrane glycoprotein that belongs to the immunoglobulin superfamily, and cyclophilin A (CypA), one of the binding partners of CD147, are overexpressed in tumor cells and associated with the progression of several malignancies, including both solid and hematological malignancies. However, CD147 and CypA involvement in cutaneous T-cell lymphoma (CTCL) has not been reported. In this study, we examined CD147 and CypA expression and function using clinical samples of mycosis fungoides (MF) and Sézary syndrome (SS) and CTCL cell lines. CD147 and CypA were overexpressed by tumor cells of MF/SS, and CypA was also expressed by epidermal keratinocytes in MF/SS lesional skin. Serum CypA levels were increased and correlated with disease severity markers in MF/SS patients. Anti-CD147 antibody and/or anti-CypA antibody suppressed the proliferation of CTCL cell lines, both in vitro and in vivo, via downregulation of phosphorylated extracellular-regulated kinase 1/2 and Akt. These results suggest that CD147-CypA interactions can contribute to the proliferation of MF/SS tumor cells in both a autocrine and paracrine manner, and that the disruption of CD147-CypA interactions could be a new therapeutic strategy for the treatment of MF/SS.     

Filter-based energy-resolved X-ray computed tomography with a clinical imager

Filter-based energy-resolved X-ray computed tomography (CT) is an approach for implementing energy-resolved CT imaging using a flat-panel-detector-based cone-beam system. In this study, we performed experiments with a 20-cm-diameter phantom on a clinical X-ray imager. The material density results showed good agreement with the ideal values. We also propose an improved method for obtaining the detector response function and the X-ray spectrum, which requires fewer measurements and will be practical for future clinical use. Issues such as scatter and image noise remain to be addressed.     

Chemical (Sr,Co)-doping effect on critical current density for Dy123 melt-solidified bulks

The dilute impurity doping for CuO-chain site was found to largely improve the critical current properties of both Y123 single crystals and Y123 melt-solidified bulks in our previous study. In addition, dilute Sr-doping to Ba site is also effective for enhancement of J_c without serious decrease in T_c as in the case of dilute Zn doping for CuO₂-plane site. In the present study, we have attempted further enhancement of flux pinning force of the Dy123 melt-solidified bulk, which is essentially more promising materials than Y123, by impurity doping for Cu site in the CuO-chain and for Ba site. Although the (Sr,Co)-co-doped Dy123 melt-solidified bulks showed systematically suppressed T_c with their doping levels, high T_c's well exceeding 90 K were maintained. All the Sr-doped or Co-doped Dy123 bulks exhibited higher J_c than the undoped one. More improved J_c properties were achieved by (Sr,Co)-co-doping, suggesting that pinning potential at local regions around doped impurities become deeper by Co-doping, resulting in stronger point-defect-like pinning sites. In addition, more detailed studies on the dilute Sr-doping and the dilute (Sr,Co)-Co-doping were carried out for Y123 single crystals in order to clarify the difference between their doping effects on the J_c properties. The vortex transition field, H^*, to the disordered state in the M–H loops for the Co-doped Y123 single crystal was located at the lower field than that of the Sr-doped one, meaning that the Co ions strongly affect the vortex system compared with the Sr ions.     

Eudragit Coating of Chitosan-Prednisolone Conjugate Microspheres and In Vitro Evaluation of Coated Microspheres

Chitosan-prednisolone conjugate microspheres (Ch-SP-MS) were prepared, and Eudragit coating was applied in order to efficiently deliver the microspheres and drug to the intestinal disease sites. The Eudragit L100-coated microspheres (Ch-SP-MS/EuL100) were examined for particle characteristics and the release of drug and Ch-SP-MS in different pH media at 37°C. Ch‐SP-MS were spherical, with a mean size of 4.5 μm and prednisolone content of 3.3% (w/w). Ch-SP-MS/EuL100 were fairly spherical, with a mean size of 22. 5 μm and drug content of 0.32% (w/w). At pH 1.2, the release extent was less than 5% even at 48 h, and Eudragit coating tended to suppress the release. In contrast, at pH 6.8 and 7.4, Ch-SP-MS/EuL100 tended to show somewhat faster drug release than Ch-SP-MS. Ch-SP-MS/EuL100 displayed a release extent of 23 and 27% at pH 6.8 and 7.4, respectively. Ch-SP-MS aggregated at pH 1.2, but almost kept their initial size and shape at pH 6.8 and 7.4. Ch-SP-MS/EuL100 almost maintained their original shape and size at pH 1.2, and gradually released Ch-SP-MS at pH 6.8 and 7.4 due to dissolution of the Eudragit layer. Eudragit coating is suggested to be useful to efficiently deliver Ch-SP-MS to the intestinal disease sites.