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141.
Interleukin 10 (IL-10) is a potent immunosuppressive cytokine, therefore elevated IL-10 expression has been implicated in inhibition of antitumor immune response. IL-10 gene promoter polymorphism has been shown to be involved in susceptibility to skin cancers, but there has been no report focusing on susceptibility to skin cancers among non-Caucasian populations. We enrolled 129 patients with skin cancers and 50 age- and sex-matched healthy controls between April 2004 and March 2007. Genomic DNA was extracted from patients' blood samples and IL-10 promoter polymorphisms were identified using polymerase chain reaction-restriction fragment length polymorphism or direct sequencing. The distribution of the frequency of allele or haplotype of IL-10 gene promoter in Japanese was quite different from that of Europeans. No significant differences could be demonstrated in the frequency of allele or haplotype of IL-10 gene promoter between the patient group and the control group. However, the frequency of the low-IL-10 expression haplotype was significantly high in Bowen's disease subgroup. The frequency of low expression IL-10 promoter genotype was significantly less (P = 0.009, chi(2) = 6.74) in the group of nonmelanoma skin cancer generated on sun-exposed areas in comparison with that on covered areas. Our results indicated that low expression haplotype of IL-10 in Bowen's disease may inhibit the escape of tumor cells from immune surveillance, resulting in suppression of tumor growth and tumor invasion to the dermis. Moreover, high IL-10-expressing haplotype of IL-10 promoter may be a risk factor for photocarcinogenesis. 相似文献
142.
On-chip screening method for cell migration genes based on a transfection microarray 总被引:1,自引:0,他引:1
Onuki-Nagasaki R Nagasaki A Hakamada K Uyeda TQ Fujita S Miyake M Miyake J 《Lab on a chip》2008,8(9):1502-1506
Cell migration plays a major role in a variety of biological processes and a detailed understanding of associated mechanisms should lead to advances in the medical sciences, for example, in drug discovery for cancer therapy. However, the traditional methods used for analysis of cell migration cannot easily be scaled up for high-throughput screening. In this study, we have attempted to develop a novel simple method for high-throughput phenotypic screening for the identification of genes that are required for cell migration. As the appropriate cell line for the method, we found NBT-L2b cells that would be suitable for screening of migration-related genes in our method without influence by other cellular processes. Moreover, the idea for printing both the labeled fibronectin, for identification of the starting region of a cell, and the green fluorescent protein (GFP) expression vector, for identification of cells that had been transfected with siRNA and of the end point of migration, brings a rapid and efficient high-throughput screening procedure. Our new method will lead to an enhanced understanding of cell migration. 相似文献
143.
Ken-ichi Fujita Yoshinori Takahashi Hirohide Nakaguma Taro Hamada Ryohei Yamaguchi 《Journal of organometallic chemistry》2008,693(21-22):3375-3382
Reactions of [(Cp1Ir)2(μ-dmpm)(μ-H)2][OTf]2 (1) with NaOtBu in aromatic solvent at room temperature give [(Cp1Ir)(H)(μ-dmpm)(μ-H)(Cp1Ir)(Ar)][OTf] [Ar = Ph (3), p-Tol (4a), m-Tol (4b), 2-furyl (5a), 3-furyl (5b)] via intermolecular aromatic C–H activation. Treatment of [(Cp1Ir)2(μ-dppm)(μ-H)2][OTf]2 (2) with weak base (Et2NH) results in intramolecular C–H activation of a phenyl group in the dppm ligand to give [(Cp1Ir)(H){μ-PPh(C6H4)CH2PPh2}(μ-H)(Cp1Ir)][OTf] (6). Reaction of 1 with NaOtBu in tetrahydrofuran under H2 (1 atm) results in activation of the H–H bond to give [{(Cp1Ir)(H)}2(μ-dmpm)(μ-H)][OTf] (7). Reaction of 1 with NaOtBu in dichloromethane under carbon monoxide (1 atm) gives a carbonyl-bridged IrII–IrII complex, [(Cp1Ir)2(μ-dmpm)(μ-H)(μ-CO)][OTf] (8-OTf). These results strongly suggest that the active species in C–H and H–H bond activation starting with 1 and 2 would be unsaturated 32e? diiridium species. The structures of 3, 5a, 6, 7, and 8-BPh4 have been determined by X-ray diffraction methods. 相似文献
144.
Taro Takaguchi Yosuke Yano Yuichi Yoshida 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(2):35
Structure of real networked systems, such as social relationship, can be modeled as temporal networks in which each edge appears only at the prescribed time. Understanding the structure of temporal networks requires quantifying the importance of a temporal vertex, which is a pair of vertex index and time. In this paper, we define two centrality measures of a temporal vertex based on the fastest temporal paths which use the temporal vertex. The definition is free from parameters and robust against the change in time scale on which we focus. In addition, we can efficiently compute these centrality values for all temporal vertices. Using the two centrality measures, we reveal that distributions of these centrality values of real-world temporal networks are heterogeneous. For various datasets, we also demonstrate that a majority of the highly central temporal vertices are located within a narrow time window around a particular time. In other words, there is a bottleneck time at which most information sent in the temporal network passes through a small number of temporal vertices, which suggests an important role of these temporal vertices in spreading phenomena. 相似文献
145.
Boot CM Amagata T Tenney K Compton JE Pietraszkiewicz H Valeriote FA Crews P 《Tetrahedron》2007,63(39):9903-9914
The structures and biological properties of peptides produced by two genera of marine-derived fungi, an atypical Acremonium sp., and a Metarrhizium sp., were explored. The Acremonium strain was isolated from a marine sponge and has previously been shown by our group to produce peptides from the efrapeptin and RHM families. The isolation and structural elucidation of the new linear pentadecapeptides efrapeptins Eα (1) and H (2) and N-methylated octapeptides RHM3 (3) and RHM4 (4) were carried out through a combination of 1D and 2D NMR techniques and tandem MS. Additional known efrapeptins E, F, and G and the known syctalidamides A and B were also isolated. The absolute configurations of 1-4 are proposed to be the same as the original compound families. The marine sponge-derived Metarrhizium sp. was shown to produce destruxin cyclic depsipeptides including A, B, B2, desmethyl B, E chlorohydrin, and E2 chlorohydrin. Efrapeptins Eα (1), F, and G each displayed IC50s of 1.3 nM against H125 cells, and destruxin E2 chlorohydrin displayed an IC50 of 160 nM against HCT-116 cells. An initial therapeutic assessment suggested a continuous (168 h) exposure of at least 2 ng/mL, or a daily (24 h) exposure of at least 300 ng/mL for H125 cells treated with efrapeptin G, and a continuous (168 h) exposure of at least 190 ng/mL for HCT-116 cells treated with destruxin E2 chlorohydrin, will cause 90% tumor cell death in vitro. 相似文献
146.
The rhizomes of Convallaria majalis have been analyzed for their steroidal glycoside constituents, resulting in the isolation of a new 5beta-spirostanol triglycoside, named convallasaponin A, along with two known cardenolide glycosides and a known cholestane glycoside. The structure of convallasaponin A was determined on the basis of extensive spectroscopic analysis, including 2D NMR data, and the results of hydrolytic cleavage. The cardenolide glycosides showed tumor specific cytotoxic activity. 相似文献
147.
Itou Y Mori S Udagawa T Tachikawa M Ishimoto T Nagashima U 《The journal of physical chemistry. A》2007,111(2):261-267
The geometric and kinetic isotope effects (GIE and KIE) for thermal [1,5]-sigmatropic H and D shifts of (Z)-1,3-pentadiene were studied by including the direct quantum effect of the migrating H or D nucleus in the multi-component molecular orbital-Hartree-Fock (MC_MO-HF) method. Based on the results, the C(1)-D bond lengths are 0.007 Angstrom shorter than the C1-H bond lengths in both the reactant (A) and the transition states (TS), whereas other bond lengths resemble those between H and D. The ratio of the rate constant (k(H)/k(D)) of the reaction for the thermal [1,5]-H and D shifts determined using the MC_MO-HF method (8.28) is closer to the experimental value (12.2) than that determined using either the conventional restricted Hartree-Fock (4.10) or restricted M?ller-Plesset second-order perturbation (3.79) methods. 相似文献
148.
Spatial light modulator with an over-two-octave bandwidth from ultraviolet to near infrared 总被引:1,自引:0,他引:1
We developed a 1-pixel ultraviolet-to-near-infrared (UV-to-NIR) liquid-crystal spatial light modulator (LC-SLM) and clarified its phase modulation properties in detail, for the first time to our knowledge. The employed liquid crystal is transparent over 260-1100 nm. A phase modulation capability of 55.8 rad at 305 nm and 14.0 rad at 1000 nm is enough to compensate for UV-to-NIR nonlinear chirped pulses. The LC-SLM driving parameters of a period T=13 ms and an applied voltage V(DD)=7.0 V were determined. The 648-pixel extension of this new device will permit us to realize the high-power generation of single subcycle optical pulses and the direct UV-to-NIR pulse shaping. 相似文献
149.
Manjinder Singh Jonathan W. Naughton Taro Yamashita Hiroki Nagai Keisuke Asai 《Experiments in fluids》2011,50(3):701-714
Phase-locked PSP and PIV measurements were used to study the evolution of three-dimensional disturbances produced by an oscillating
fence actuator immersed in a zero pressure gradient turbulent boundary layer. For the single fence frequency studied, strong
three-dimensionality is observed in the vortical structure that varies along the span of the fence soon after the fence enters
the flow. At the midspan, the structure grows, weakens, and convects faster than at other locations. As the fence height increases,
the data indicate that the vortical structure terminates near the edge of the fence. In contrast, the vortex structure terminates
on the plate surface adjacent to the fence edge as the fence descends, similar to a wake vortex of a stationary obstacle.
This study demonstrates that the combined use of surface and flow-field diagnostics provide a link between flow field and
surface features, yielding an understanding of the flow that would have not been possible with any one technique. 相似文献
150.
In this study, a frozen water phase method for log D measurement using a 96-well plate was developed. In the case of log D measurement of compounds, the problem of octanol contamination often occurs; in lipophilic compounds, the concentration of the octanol phase is much higher than that of the water phase. When the water phase is separated from the octanol phase, a small amount of octanol phase contamination could strongly influence the concentration of the water phase. To avoid this problem, the frozen water phase method was developed. The water phase was frozen in liquid nitrogen and then the unfrozen octanol phase was removed. To remove the portion of the octanol remaining on the frozen water phase, the surface of the frozen water phase was washed with octanol and water/ethanol (50/50, v/v). The validity of the method was confirmed by results of commercially available drugs at the log D range from 0 to 4. Further, it was found that this method had the ability to evaluate the pH-log D profile of compounds in the range from pH 2 to pH 12. As a result, we developed the convenient and accurate method that is effective in preventing contamination with a wide dynamic range. 相似文献