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81.
Sergio Di Nuzzo Menno A. de Rie Chris M. van der Loos Jan D. Bos Marcel B. M. Teunissen 《Photochemistry and photobiology》1996,64(6):988-993
Abstract— The proportion and composition of the human cutaneous CD3+ T lymphocyte population was determined in situ following a single exposure to physiological, erythema-inducing doses of simulated solar radiation, mainly consisting of UV radiation. Biopsies were taken 1, 2 and 7 days after local irradiation of normal volunteers with 1,2 and 4 MED by a xenonarc lamp and immunohistochemistry was performed on cryostat sections. Ultraviolet radiation caused an initial decrease of intraepidermal CD3+ T-cell numbers or even could lead to T-cell depletion 24 and 48 h postirradiation, and this was followed by an infiltration of T cells in the epidermis as determined 1 week after UV exposure. The number of dermal CD3+ T ceDs was increased 24 h after irradiation, reached a maximum at 48 h and subsequently declined at day 7, though remained significantly higher than the unirradiated control Double staining demonstrated that the CD3+ T cells, which immigrated into the (epi)dermis upon UV exposure, coexpressed CD4 but not CD8. Therefore the CD4/CD8 ratio in skin was markedly increased during the first week upon UV exposure. Our time course study shows that UV radiation affects die T-cell population within human skin by depleting the majority of epidermal T cells and initiating a selective influx of CD4+ T cells. 相似文献
82.
Single crystals of the strontium copper tellurium oxochloride SrCu2(TeO3)2Cl2 were synthesized via solid-gas reactions in sealed evacuated silica tubes. The compound crystallizes in the monoclinic system, space group P21, a=7.215(2), b=7.2759(15), c=8.239(2) Å, β=96.56(4)°, Z=2. The building units are [SrO6Cl2] irregular polyhedra, [CuO4] and [CuO3Cl] square planes, [TeO3E] tetrahedra and [TeO3+1E] trigonal bipyramids; E being the 5s2 lone pair of Te(IV). The Cu atoms can be regarded as forming a chain of weakly connected dimers. The magnetic susceptibility of the compound shows a broad maximum typical for antiferromagnetic spin fluctuations with a non-magnetic ground state. A Heisenberg spin model with coupled s=1/2 dimers leads to a satisfactory fitting of the experimental data. 相似文献
83.
Hideyuki Shiozawa Rosa Zerella Ben Bardsley KellieL. Tuck DudleyH. Williams 《Helvetica chimica acta》2003,86(5):1359-1370
A wide range of dimerisation constants (Kdim ca. 101–106 M ?1) for various glycopeptide antibiotics have been determined. We consider these dimerisation constants in the light of the published X‐ray structures of the antibiotics, in particular, the relationship between K dim and the length of a specified distance at the dimer interface. In the crystals, we find that this distance is smaller for strongly dimerising antibiotics and larger for weakly dimerising antibiotics. Thus, the dimerisation constant is correlated with tightness at the dimer interface. Despite the crystal‐packing forces exerted between adjacent dimer molecules in the crystals, the noncovalent bond distances at the dimer interface are correlated with the distances in solution (inferred from solution NMR data). These observations can account for the benefits in enthalpy, and costs in entropy, associated with positively cooperative binding. 相似文献
84.
A fast method to obtain a quantitative structure-retention relationship is required in chromatography for the rapid optimization of chromatographic separation conditions. Chromatographic data of acidic drugs are analyzed by a computational chemical method to simulate chromatographic simulation. The direct interaction between a model phase and a drug is calculated as an energy value using the molecular mechanics calculation of CAChe. Computational chemistry using a model adsorbent is a new method for quantitative analysis of retention in reversed-phase liquid chromatography. The correlation coefficient is 0.878 (n = 19) between the retention factors of acidic drugs and interaction energy values of the final structure (DeltaFS) between an acidic drug and model pentyl-bonded phase. 相似文献
85.
86.
Saori Ichinose Mayumi Nakamura Mayu Maeda Rie Ikeda Mitsuhiro Wada Mio Nakazato Yoshihito Ohba Noboru Takamura Takahiro Maeda Kiyoshi Aoyagi Kenichiro Nakashima 《Biomedical chromatography : BMC》2009,23(9):935-939
A semi‐micro column HPLC‐fluorescence method for routine determination of thiol derivatives such as homocysteine (Hcy), cysteine (Cys) and cysteamine (CA) is described. The thiol derivatives labeled with ammonium‐7‐fluorobenzo‐2‐oxa‐1,3‐diazole‐4‐sulfonate (SBD‐F) were isocratically separated within 12 min on a semi‐micro ODS column (Daisopak‐SP‐120‐5‐ODS‐BP) with a mixture of 25 mm acetate buffer (pH 2.00) and CH3CN as a mobile phase. The purity and similarity of SBD‐thiols by a multi‐wavelength fluorescence detector were more than 92.3 and 96.7%. The detection limits of Hcy, Cys and CA at a signal‐to‐noise ratio of 3 were 0.16, 0.47 and 0.03 µm , respectively. Furthermore validation parameters such as accuracy, precision and robustness of the proposed method showed satisfactory results. Almost 850 plasma sample injections (range 572–1076, n = 3) for a column could be performed without differences in retention time and peak heights of labels. As an application of the proposed method, the determination of thiol derivatives in normal human plasma (n = 103) was demonstrated. The correlation coefficients between Hcy vs Cys and Hcy vs CA were 0.38 and −0.35, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
87.
Masahide Takahashi Masaru Suzuki Yuya Miyagawa Rie Ihara Yomei Tokuda Toshinobu Yoko Takashi Nemoto Seiji Isoda 《Journal of Sol-Gel Science and Technology》2010,54(3):319-324
Photo-curable vinyl modified silicate-phosphate alternating copolymers were prepared by a direct condensation of organochlorosilane
and organophosphoric acid in a solvent-free condition. The obtained copolymers have complete alternating copolymer structure
of silicate and phosphate unit, where the main oxo chain consist of –(Si–O–P–O)
n
-network. They exhibited an excellent solubility of ionic species such as ionic organic dyes. It was also demonstrated the
photo-reduction of Au+ ions to form Au nano particles for plasmonics applications. Micro patterns were also fabricated by soft lithographic processes.
These results indicate that the photo-curable alternating copolymers are one of promising materials for advanced optical information
processing devices. 相似文献
88.
89.
Masaki Matsui Rie Ikeda Yasuhiro Kubota Kazumasa Funabiki 《Tetrahedron letters》2009,50(35):5047-6547
The solid-state fluorescence of 2-amino-, 2-ethylamino, 2-diethylamino-, and 2,7-bis(diethylamino)perfluorophenazines was examined. They showed their fluorescence maxima in the range of 584-637 nm. The solid-state fluorescence quantum yield of 2-diethylamino derivative was highest among these derivatives, there being 0.22. X-ray crystallographic analysis suggests that the 2-diethylamino derivative has no strong intermolecular interactions among adjacent molecules to show intense fluorescence, whereas the other derivatives have network NH/F hydrogen, π-π, and CH/F interactions to reduce solid-state fluorescence intensity. 相似文献
90.
Rie Shishido 《Surface and interface analysis : SIA》2022,54(3):203-211
Bi cluster time-of-flight secondary ion mass spectrometry (TOF-SIMS) is a useful method for evaluating organic surfaces. However, its ability to detect large molecules is limited. One of the problems is that the sensitivities of macromolecules are lower than those of small molecules because larger molecules tend to exhibit lower ionization efficiencies and/or higher probabilities of fragmentation. Matrix-enhanced (ME)-SIMS is a sensitivity enhancement technique for intact molecular ions. The crystal structure of a mixed substance composed of an analyte and a matrix is known to affect the sensitivity of the analysis target. In this study, the effect of cocrystallization, which occurs due to the presence of bile acid, on the molecular-ion sensitivity was investigated using Bi cluster TOF-SIMS. Biological phospholipids and bile acids, which exhibit surfactant behaviors, were selected as the evaluated molecules and additives, respectively. The mass spectra indicated that the secondary-ion yields of phospholipids with bile acid were substantially greater than those of the pristine lipid. Specifically, samples with an analyte/bile acid ratio of 1:100 achieved approximately 60–100-fold sensitivity enhancement of [M + H]+ and [2M + H]+ molecular ions than the sensitivity achieved with the pristine samples. In the evaluation of molecular distribution, higher signal counts of intact ions were obtained from the cocrystallization area, although less-fragmented ions were emitted from these regions. Consequently, the results indicate that the cocrystallization due to the presence of bile acid provides an effective crystal structure for facilitating emission of larger molecules. 相似文献